comparing 97420d1930c4c7cd6b5701f5c5a3a09bfbd17b93 and feat/dpop-token-binding on bretton.dev/coves

+24 -3

cmd/server/main.go

···

       36
        
       	commentsAPI "Coves/internal/api/handlers/comments"

     

       37
        
       

     

       38
        
       	postgresRepo "Coves/internal/db/postgres"

     

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       39
        
       )

     

       40
        
       

     

       41
        
       func main() {

     
···

       142
        
       		log.Println("   Set AUTH_SKIP_VERIFY=false for production")

     

       143
        
       	}

     

       144
        
       

     

       145
       -
       	jwksCacheTTL := 1 * time.Hour // Cache public keys for 1 hour

     

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       146
        
       	jwksFetcher := auth.NewCachedJWKSFetcher(jwksCacheTTL)

     

       147
       -
       	authMiddleware := middleware.NewAtProtoAuthMiddleware(jwksFetcher, skipVerify)

     

       148
       -
       	log.Println("✅ atProto auth middleware initialized")

     

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       149
        
       

     

       150
        
       	// Initialize repositories and services

     

       151
        
       	userRepo := postgresRepo.NewUserRepository(db)

···

       36
        
       	commentsAPI "Coves/internal/api/handlers/comments"

     

       37
        
       

     

       38
        
       	postgresRepo "Coves/internal/db/postgres"

     

       39
       +
       

     

       40
       +
       	indigoIdentity "github.com/bluesky-social/indigo/atproto/identity"

     

       41
        
       )

     

       42
        
       

     

       43
        
       func main() {

     
···

       144
        
       		log.Println("   Set AUTH_SKIP_VERIFY=false for production")

     

       145
        
       	}

     

       146
        
       

     

       147
       +
       	// Initialize Indigo directory for DID resolution (used by auth)

     

       148
       +
       	plcURL := os.Getenv("PLC_DIRECTORY_URL")

     

       149
       +
       	if plcURL == "" {

     

       150
       +
       		plcURL = "https://plc.directory"

     

       151
       +
       	}

     

       152
       +
       	indigoDir := &indigoIdentity.BaseDirectory{

     

       153
       +
       		PLCURL:     plcURL,

     

       154
       +
       		HTTPClient: http.Client{Timeout: 10 * time.Second},

     

       155
       +
       	}

     

       156
       +
       

     

       157
       +
       	// Initialize JWT config early to cache HS256_ISSUERS and PDS_JWT_SECRET

     

       158
       +
       	// This avoids reading env vars on every request

     

       159
       +
       	auth.InitJWTConfig()

     

       160
       +
       

     

       161
       +
       	// Create combined key fetcher for both DID and URL issuers

     

       162
       +
       	// - DID issuers (did:plc:, did:web:) → resolved via DID document keys (ES256)

     

       163
       +
       	// - URL issuers → JWKS endpoint (fallback for legacy tokens)

     

       164
       +
       	jwksCacheTTL := 1 * time.Hour

     

       165
        
       	jwksFetcher := auth.NewCachedJWKSFetcher(jwksCacheTTL)

     

       166
       +
       	keyFetcher := auth.NewCombinedKeyFetcher(indigoDir, jwksFetcher)

     

       167
       +
       

     

       168
       +
       	authMiddleware := middleware.NewAtProtoAuthMiddleware(keyFetcher, skipVerify)

     

       169
       +
       	log.Println("✅ atProto auth middleware initialized (DID + JWKS key resolution)")

     

       170
        
       

     

       171
        
       	// Initialize repositories and services

     

       172
        
       	userRepo := postgresRepo.NewUserRepository(db)

.env.dev

···

       152
        
       # When false, verifies JWT signature against issuer's JWKS

     

       153
        
       AUTH_SKIP_VERIFY=true

     

       154
        
       

     

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       155
        
       # Logging

     

       156
        
       LOG_LEVEL=debug

     

       157
        
       LOG_ENABLED=true

···

       152
        
       # When false, verifies JWT signature against issuer's JWKS

     

       153
        
       AUTH_SKIP_VERIFY=true

     

       154
        
       

     

       155
       +
       # HS256 Issuers: PDSes allowed to use HS256 (shared secret) authentication

     

       156
       +
       # Must share PDS_JWT_SECRET with Coves instance. External PDSes use ES256 via DID resolution.

     

       157
       +
       # For local dev, allow the local PDS or turn AUTH_SKIP_VERIFY = true

     

       158
       +
       HS256_ISSUERS=http://localhost:3001

     

       159
       +
       

     

       160
        
       # Logging

     

       161
        
       LOG_LEVEL=debug

     

       162
        
       LOG_ENABLED=true

+28

.env.prod.example

···

       26
        
       # PDS_EMAIL_SMTP_URL=smtp://user:pass@smtp.example.com:587

     

       27
        
       # PDS_EMAIL_FROM_ADDRESS=noreply@coves.me

     

       28
        
       

     

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       29
        
       # =============================================================================

     

       30
        
       # AppView OAuth (for mobile app authentication)

     

       31
        
       # =============================================================================

···

       26
        
       # PDS_EMAIL_SMTP_URL=smtp://user:pass@smtp.example.com:587

     

       27
        
       # PDS_EMAIL_FROM_ADDRESS=noreply@coves.me

     

       28
        
       

     

       29
       +
       # =============================================================================

     

       30
       +
       # JWT Authentication

     

       31
       +
       # =============================================================================

     

       32
       +
       # Coves supports two JWT verification methods:

     

       33
       +
       #

     

       34
       +
       # 1. HS256 (shared secret) - For your own PDS

     

       35
       +
       #    - Fast, no network calls needed

     

       36
       +
       #    - Requires shared PDS_JWT_SECRET

     

       37
       +
       #    - Only for PDSes you control

     

       38
       +
       #

     

       39
       +
       # 2. ES256 (DID resolution) - For federated users

     

       40
       +
       #    - Works with any PDS (bsky.social, etc.)

     

       41
       +
       #    - Resolves user's DID document to get public key

     

       42
       +
       #    - No shared secret needed

     

       43
       +
       #

     

       44
       +
       # HS256_ISSUERS: Comma-separated list of PDS URLs allowed to use HS256

     

       45
       +
       # These PDSes MUST share the same PDS_JWT_SECRET with Coves

     

       46
       +
       # Example: HS256_ISSUERS=https://pds.coves.social,https://pds.example.com

     

       47
       +
       HS256_ISSUERS=https://pds.coves.me

     

       48
       +
       

     

       49
       +
       # PLC Directory URL for DID resolution (optional)

     

       50
       +
       # Defaults to https://plc.directory if not set

     

       51
       +
       # PLC_DIRECTORY_URL=https://plc.directory

     

       52
       +
       

     

       53
       +
       # Skip JWT signature verification (DEVELOPMENT ONLY!)

     

       54
       +
       # Set to false in production for proper security

     

       55
       +
       AUTH_SKIP_VERIFY=false

     

       56
       +
       

     

       57
        
       # =============================================================================

     

       58
        
       # AppView OAuth (for mobile app authentication)

     

       59
        
       # =============================================================================

docker-compose.prod.yml

···

       96
        
             # Cursor encryption for pagination

     

       97
        
             CURSOR_SECRET: ${CURSOR_SECRET}

     

       98
        
       

     

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       0
        
       
     

       99
        
             # Restrict community creation to instance DID only

     

       100
        
             COMMUNITY_CREATORS: did:web:coves.social

     

       101
        
           networks:

···

       96
        
             # Cursor encryption for pagination

     

       97
        
             CURSOR_SECRET: ${CURSOR_SECRET}

     

       98
        
       

     

       99
       +
             # PDS JWT secret for verifying HS256 tokens from the PDS

     

       100
       +
             # Must match the PDS_JWT_SECRET configured on the PDS

     

       101
       +
             PDS_JWT_SECRET: ${PDS_JWT_SECRET}

     

       102
       +
             # Whitelist PDS issuer(s) allowed to use HS256 (no kid)

     

       103
       +
             HS256_ISSUERS: ${HS256_ISSUERS}

     

       104
       +
       

     

       105
        
             # Restrict community creation to instance DID only

     

       106
        
             COMMUNITY_CREATORS: did:web:coves.social

     

       107
        
           networks:

+484

internal/atproto/auth/dpop.go

···

       1
       +
       package auth

     

       2
       +
       

     

       3
       +
       import (

     

       4
       +
       	"crypto/ecdsa"

     

       5
       +
       	"crypto/elliptic"

     

       6
       +
       	"crypto/sha256"

     

       7
       +
       	"encoding/base64"

     

       8
       +
       	"encoding/json"

     

       9
       +
       	"fmt"

     

       10
       +
       	"math/big"

     

       11
       +
       	"strings"

     

       12
       +
       	"sync"

     

       13
       +
       	"time"

     

       14
       +
       

     

       15
       +
       	indigoCrypto "github.com/bluesky-social/indigo/atproto/atcrypto"

     

       16
       +
       	"github.com/golang-jwt/jwt/v5"

     

       17
       +
       )

     

       18
       +
       

     

       19
       +
       // NonceCache provides replay protection for DPoP proofs by tracking seen jti values.

     

       20
       +
       // This prevents an attacker from reusing a captured DPoP proof within the validity window.

     

       21
       +
       // Per RFC 9449 Section 11.1, servers SHOULD prevent replay attacks.

     

       22
       +
       type NonceCache struct {

     

       23
       +
       	seen    map[string]time.Time // jti -> expiration time

     

       24
       +
       	stopCh  chan struct{}

     

       25
       +
       	maxAge  time.Duration // How long to keep entries

     

       26
       +
       	cleanup time.Duration // How often to clean up expired entries

     

       27
       +
       	mu      sync.RWMutex

     

       28
       +
       }

     

       29
       +
       

     

       30
       +
       // NewNonceCache creates a new nonce cache for DPoP replay protection.

     

       31
       +
       // maxAge should match or exceed DPoPVerifier.MaxProofAge.

     

       32
       +
       func NewNonceCache(maxAge time.Duration) *NonceCache {

     

       33
       +
       	nc := &NonceCache{

     

       34
       +
       		seen:    make(map[string]time.Time),

     

       35
       +
       		maxAge:  maxAge,

     

       36
       +
       		cleanup: maxAge / 2, // Clean up at half the max age

     

       37
       +
       		stopCh:  make(chan struct{}),

     

       38
       +
       	}

     

       39
       +
       

     

       40
       +
       	// Start background cleanup goroutine

     

       41
       +
       	go nc.cleanupLoop()

     

       42
       +
       

     

       43
       +
       	return nc

     

       44
       +
       }

     

       45
       +
       

     

       46
       +
       // CheckAndStore checks if a jti has been seen before and stores it if not.

     

       47
       +
       // Returns true if the jti is fresh (not a replay), false if it's a replay.

     

       48
       +
       func (nc *NonceCache) CheckAndStore(jti string) bool {

     

       49
       +
       	nc.mu.Lock()

     

       50
       +
       	defer nc.mu.Unlock()

     

       51
       +
       

     

       52
       +
       	now := time.Now()

     

       53
       +
       	expiry := now.Add(nc.maxAge)

     

       54
       +
       

     

       55
       +
       	// Check if already seen

     

       56
       +
       	if existingExpiry, seen := nc.seen[jti]; seen {

     

       57
       +
       		// Still valid (not expired) - this is a replay

     

       58
       +
       		if existingExpiry.After(now) {

     

       59
       +
       			return false

     

       60
       +
       		}

     

       61
       +
       		// Expired entry - allow reuse and update expiry

     

       62
       +
       	}

     

       63
       +
       

     

       64
       +
       	// Store the new jti

     

       65
       +
       	nc.seen[jti] = expiry

     

       66
       +
       	return true

     

       67
       +
       }

     

       68
       +
       

     

       69
       +
       // cleanupLoop periodically removes expired entries from the cache

     

       70
       +
       func (nc *NonceCache) cleanupLoop() {

     

       71
       +
       	ticker := time.NewTicker(nc.cleanup)

     

       72
       +
       	defer ticker.Stop()

     

       73
       +
       

     

       74
       +
       	for {

     

       75
       +
       		select {

     

       76
       +
       		case <-ticker.C:

     

       77
       +
       			nc.cleanupExpired()

     

       78
       +
       		case <-nc.stopCh:

     

       79
       +
       			return

     

       80
       +
       		}

     

       81
       +
       	}

     

       82
       +
       }

     

       83
       +
       

     

       84
       +
       // cleanupExpired removes expired entries from the cache

     

       85
       +
       func (nc *NonceCache) cleanupExpired() {

     

       86
       +
       	nc.mu.Lock()

     

       87
       +
       	defer nc.mu.Unlock()

     

       88
       +
       

     

       89
       +
       	now := time.Now()

     

       90
       +
       	for jti, expiry := range nc.seen {

     

       91
       +
       		if expiry.Before(now) {

     

       92
       +
       			delete(nc.seen, jti)

     

       93
       +
       		}

     

       94
       +
       	}

     

       95
       +
       }

     

       96
       +
       

     

       97
       +
       // Stop stops the cleanup goroutine. Call this when done with the cache.

     

       98
       +
       func (nc *NonceCache) Stop() {

     

       99
       +
       	close(nc.stopCh)

     

       100
       +
       }

     

       101
       +
       

     

       102
       +
       // Size returns the number of entries in the cache (for testing/monitoring)

     

       103
       +
       func (nc *NonceCache) Size() int {

     

       104
       +
       	nc.mu.RLock()

     

       105
       +
       	defer nc.mu.RUnlock()

     

       106
       +
       	return len(nc.seen)

     

       107
       +
       }

     

       108
       +
       

     

       109
       +
       // DPoPClaims represents the claims in a DPoP proof JWT (RFC 9449)

     

       110
       +
       type DPoPClaims struct {

     

       111
       +
       	jwt.RegisteredClaims

     

       112
       +
       

     

       113
       +
       	// HTTP method of the request (e.g., "GET", "POST")

     

       114
       +
       	HTTPMethod string `json:"htm"`

     

       115
       +
       

     

       116
       +
       	// HTTP URI of the request (without query and fragment parts)

     

       117
       +
       	HTTPURI string `json:"htu"`

     

       118
       +
       

     

       119
       +
       	// Access token hash (optional, for token binding)

     

       120
       +
       	AccessTokenHash string `json:"ath,omitempty"`

     

       121
       +
       }

     

       122
       +
       

     

       123
       +
       // DPoPProof represents a parsed and verified DPoP proof

     

       124
       +
       type DPoPProof struct {

     

       125
       +
       	RawPublicJWK map[string]interface{}

     

       126
       +
       	Claims       *DPoPClaims

     

       127
       +
       	PublicKey    interface{} // *ecdsa.PublicKey or similar

     

       128
       +
       	Thumbprint   string      // JWK thumbprint (base64url)

     

       129
       +
       }

     

       130
       +
       

     

       131
       +
       // DPoPVerifier verifies DPoP proofs for OAuth token binding

     

       132
       +
       type DPoPVerifier struct {

     

       133
       +
       	// Optional: custom nonce validation function (for server-issued nonces)

     

       134
       +
       	ValidateNonce func(nonce string) bool

     

       135
       +
       

     

       136
       +
       	// NonceCache for replay protection (optional but recommended)

     

       137
       +
       	// If nil, jti replay protection is disabled

     

       138
       +
       	NonceCache *NonceCache

     

       139
       +
       

     

       140
       +
       	// Maximum allowed clock skew for timestamp validation

     

       141
       +
       	MaxClockSkew time.Duration

     

       142
       +
       

     

       143
       +
       	// Maximum age of DPoP proof (prevents replay with old proofs)

     

       144
       +
       	MaxProofAge time.Duration

     

       145
       +
       }

     

       146
       +
       

     

       147
       +
       // NewDPoPVerifier creates a DPoP verifier with sensible defaults including replay protection

     

       148
       +
       func NewDPoPVerifier() *DPoPVerifier {

     

       149
       +
       	maxProofAge := 5 * time.Minute

     

       150
       +
       	return &DPoPVerifier{

     

       151
       +
       		MaxClockSkew: 30 * time.Second,

     

       152
       +
       		MaxProofAge:  maxProofAge,

     

       153
       +
       		NonceCache:   NewNonceCache(maxProofAge),

     

       154
       +
       	}

     

       155
       +
       }

     

       156
       +
       

     

       157
       +
       // NewDPoPVerifierWithoutReplayProtection creates a DPoP verifier without replay protection.

     

       158
       +
       // This should only be used in testing or when replay protection is handled externally.

     

       159
       +
       func NewDPoPVerifierWithoutReplayProtection() *DPoPVerifier {

     

       160
       +
       	return &DPoPVerifier{

     

       161
       +
       		MaxClockSkew: 30 * time.Second,

     

       162
       +
       		MaxProofAge:  5 * time.Minute,

     

       163
       +
       		NonceCache:   nil, // No replay protection

     

       164
       +
       	}

     

       165
       +
       }

     

       166
       +
       

     

       167
       +
       // Stop stops background goroutines. Call this when shutting down.

     

       168
       +
       func (v *DPoPVerifier) Stop() {

     

       169
       +
       	if v.NonceCache != nil {

     

       170
       +
       		v.NonceCache.Stop()

     

       171
       +
       	}

     

       172
       +
       }

     

       173
       +
       

     

       174
       +
       // VerifyDPoPProof verifies a DPoP proof JWT and returns the parsed proof

     

       175
       +
       func (v *DPoPVerifier) VerifyDPoPProof(dpopProof, httpMethod, httpURI string) (*DPoPProof, error) {

     

       176
       +
       	// Parse the DPoP JWT without verification first to extract the header

     

       177
       +
       	parser := jwt.NewParser(jwt.WithoutClaimsValidation())

     

       178
       +
       	token, _, err := parser.ParseUnverified(dpopProof, &DPoPClaims{})

     

       179
       +
       	if err != nil {

     

       180
       +
       		return nil, fmt.Errorf("failed to parse DPoP proof: %w", err)

     

       181
       +
       	}

     

       182
       +
       

     

       183
       +
       	// Extract and validate the header

     

       184
       +
       	header, ok := token.Header["typ"].(string)

     

       185
       +
       	if !ok || header != "dpop+jwt" {

     

       186
       +
       		return nil, fmt.Errorf("invalid DPoP proof: typ must be 'dpop+jwt', got '%s'", header)

     

       187
       +
       	}

     

       188
       +
       

     

       189
       +
       	alg, ok := token.Header["alg"].(string)

     

       190
       +
       	if !ok {

     

       191
       +
       		return nil, fmt.Errorf("invalid DPoP proof: missing alg header")

     

       192
       +
       	}

     

       193
       +
       

     

       194
       +
       	// Extract the JWK from the header

     

       195
       +
       	jwkRaw, ok := token.Header["jwk"]

     

       196
       +
       	if !ok {

     

       197
       +
       		return nil, fmt.Errorf("invalid DPoP proof: missing jwk header")

     

       198
       +
       	}

     

       199
       +
       

     

       200
       +
       	jwkMap, ok := jwkRaw.(map[string]interface{})

     

       201
       +
       	if !ok {

     

       202
       +
       		return nil, fmt.Errorf("invalid DPoP proof: jwk must be an object")

     

       203
       +
       	}

     

       204
       +
       

     

       205
       +
       	// Parse the public key from JWK

     

       206
       +
       	publicKey, err := parseJWKToPublicKey(jwkMap)

     

       207
       +
       	if err != nil {

     

       208
       +
       		return nil, fmt.Errorf("invalid DPoP proof JWK: %w", err)

     

       209
       +
       	}

     

       210
       +
       

     

       211
       +
       	// Calculate the JWK thumbprint

     

       212
       +
       	thumbprint, err := CalculateJWKThumbprint(jwkMap)

     

       213
       +
       	if err != nil {

     

       214
       +
       		return nil, fmt.Errorf("failed to calculate JWK thumbprint: %w", err)

     

       215
       +
       	}

     

       216
       +
       

     

       217
       +
       	// Now verify the signature

     

       218
       +
       	verifiedToken, err := jwt.ParseWithClaims(dpopProof, &DPoPClaims{}, func(token *jwt.Token) (interface{}, error) {

     

       219
       +
       		// Verify the signing method matches what we expect

     

       220
       +
       		switch alg {

     

       221
       +
       		case "ES256":

     

       222
       +
       			if _, ok := token.Method.(*jwt.SigningMethodECDSA); !ok {

     

       223
       +
       				return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])

     

       224
       +
       			}

     

       225
       +
       		case "ES384", "ES512":

     

       226
       +
       			if _, ok := token.Method.(*jwt.SigningMethodECDSA); !ok {

     

       227
       +
       				return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])

     

       228
       +
       			}

     

       229
       +
       		case "RS256", "RS384", "RS512", "PS256", "PS384", "PS512":

     

       230
       +
       			// RSA methods - we primarily support ES256 for atproto

     

       231
       +
       			return nil, fmt.Errorf("RSA algorithms not yet supported for DPoP: %s", alg)

     

       232
       +
       		default:

     

       233
       +
       			return nil, fmt.Errorf("unsupported DPoP algorithm: %s", alg)

     

       234
       +
       		}

     

       235
       +
       		return publicKey, nil

     

       236
       +
       	})

     

       237
       +
       	if err != nil {

     

       238
       +
       		return nil, fmt.Errorf("DPoP proof signature verification failed: %w", err)

     

       239
       +
       	}

     

       240
       +
       

     

       241
       +
       	claims, ok := verifiedToken.Claims.(*DPoPClaims)

     

       242
       +
       	if !ok {

     

       243
       +
       		return nil, fmt.Errorf("invalid DPoP claims type")

     

       244
       +
       	}

     

       245
       +
       

     

       246
       +
       	// Validate the claims

     

       247
       +
       	if err := v.validateDPoPClaims(claims, httpMethod, httpURI); err != nil {

     

       248
       +
       		return nil, err

     

       249
       +
       	}

     

       250
       +
       

     

       251
       +
       	return &DPoPProof{

     

       252
       +
       		Claims:       claims,

     

       253
       +
       		PublicKey:    publicKey,

     

       254
       +
       		Thumbprint:   thumbprint,

     

       255
       +
       		RawPublicJWK: jwkMap,

     

       256
       +
       	}, nil

     

       257
       +
       }

     

       258
       +
       

     

       259
       +
       // validateDPoPClaims validates the DPoP proof claims

     

       260
       +
       func (v *DPoPVerifier) validateDPoPClaims(claims *DPoPClaims, expectedMethod, expectedURI string) error {

     

       261
       +
       	// Validate jti (unique identifier) is present

     

       262
       +
       	if claims.ID == "" {

     

       263
       +
       		return fmt.Errorf("DPoP proof missing jti claim")

     

       264
       +
       	}

     

       265
       +
       

     

       266
       +
       	// Validate htm (HTTP method)

     

       267
       +
       	if !strings.EqualFold(claims.HTTPMethod, expectedMethod) {

     

       268
       +
       		return fmt.Errorf("DPoP proof htm mismatch: expected %s, got %s", expectedMethod, claims.HTTPMethod)

     

       269
       +
       	}

     

       270
       +
       

     

       271
       +
       	// Validate htu (HTTP URI) - compare without query/fragment

     

       272
       +
       	expectedURIBase := stripQueryFragment(expectedURI)

     

       273
       +
       	claimURIBase := stripQueryFragment(claims.HTTPURI)

     

       274
       +
       	if expectedURIBase != claimURIBase {

     

       275
       +
       		return fmt.Errorf("DPoP proof htu mismatch: expected %s, got %s", expectedURIBase, claimURIBase)

     

       276
       +
       	}

     

       277
       +
       

     

       278
       +
       	// Validate iat (issued at) is present and recent

     

       279
       +
       	if claims.IssuedAt == nil {

     

       280
       +
       		return fmt.Errorf("DPoP proof missing iat claim")

     

       281
       +
       	}

     

       282
       +
       

     

       283
       +
       	now := time.Now()

     

       284
       +
       	iat := claims.IssuedAt.Time

     

       285
       +
       

     

       286
       +
       	// Check clock skew (not too far in the future)

     

       287
       +
       	if iat.After(now.Add(v.MaxClockSkew)) {

     

       288
       +
       		return fmt.Errorf("DPoP proof iat is in the future")

     

       289
       +
       	}

     

       290
       +
       

     

       291
       +
       	// Check proof age (not too old)

     

       292
       +
       	if now.Sub(iat) > v.MaxProofAge {

     

       293
       +
       		return fmt.Errorf("DPoP proof is too old (issued %v ago, max %v)", now.Sub(iat), v.MaxProofAge)

     

       294
       +
       	}

     

       295
       +
       

     

       296
       +
       	// SECURITY: Check for replay attack using jti

     

       297
       +
       	// Per RFC 9449 Section 11.1, servers SHOULD prevent replay attacks

     

       298
       +
       	if v.NonceCache != nil {

     

       299
       +
       		if !v.NonceCache.CheckAndStore(claims.ID) {

     

       300
       +
       			return fmt.Errorf("DPoP proof replay detected: jti %s already used", claims.ID)

     

       301
       +
       		}

     

       302
       +
       	}

     

       303
       +
       

     

       304
       +
       	return nil

     

       305
       +
       }

     

       306
       +
       

     

       307
       +
       // VerifyTokenBinding verifies that the DPoP proof binds to the access token

     

       308
       +
       // by comparing the proof's thumbprint to the token's cnf.jkt claim

     

       309
       +
       func (v *DPoPVerifier) VerifyTokenBinding(proof *DPoPProof, expectedThumbprint string) error {

     

       310
       +
       	if proof.Thumbprint != expectedThumbprint {

     

       311
       +
       		return fmt.Errorf("DPoP proof thumbprint mismatch: token expects %s, proof has %s",

     

       312
       +
       			expectedThumbprint, proof.Thumbprint)

     

       313
       +
       	}

     

       314
       +
       	return nil

     

       315
       +
       }

     

       316
       +
       

     

       317
       +
       // CalculateJWKThumbprint calculates the JWK thumbprint per RFC 7638

     

       318
       +
       // The thumbprint is the base64url-encoded SHA-256 hash of the canonical JWK representation

     

       319
       +
       func CalculateJWKThumbprint(jwk map[string]interface{}) (string, error) {

     

       320
       +
       	kty, ok := jwk["kty"].(string)

     

       321
       +
       	if !ok {

     

       322
       +
       		return "", fmt.Errorf("JWK missing kty")

     

       323
       +
       	}

     

       324
       +
       

     

       325
       +
       	// Build the canonical JWK representation based on key type

     

       326
       +
       	// Per RFC 7638, only specific members are included, in lexicographic order

     

       327
       +
       	var canonical map[string]string

     

       328
       +
       

     

       329
       +
       	switch kty {

     

       330
       +
       	case "EC":

     

       331
       +
       		crv, ok := jwk["crv"].(string)

     

       332
       +
       		if !ok {

     

       333
       +
       			return "", fmt.Errorf("EC JWK missing crv")

     

       334
       +
       		}

     

       335
       +
       		x, ok := jwk["x"].(string)

     

       336
       +
       		if !ok {

     

       337
       +
       			return "", fmt.Errorf("EC JWK missing x")

     

       338
       +
       		}

     

       339
       +
       		y, ok := jwk["y"].(string)

     

       340
       +
       		if !ok {

     

       341
       +
       			return "", fmt.Errorf("EC JWK missing y")

     

       342
       +
       		}

     

       343
       +
       		// Lexicographic order: crv, kty, x, y

     

       344
       +
       		canonical = map[string]string{

     

       345
       +
       			"crv": crv,

     

       346
       +
       			"kty": kty,

     

       347
       +
       			"x":   x,

     

       348
       +
       			"y":   y,

     

       349
       +
       		}

     

       350
       +
       	case "RSA":

     

       351
       +
       		e, ok := jwk["e"].(string)

     

       352
       +
       		if !ok {

     

       353
       +
       			return "", fmt.Errorf("RSA JWK missing e")

     

       354
       +
       		}

     

       355
       +
       		n, ok := jwk["n"].(string)

     

       356
       +
       		if !ok {

     

       357
       +
       			return "", fmt.Errorf("RSA JWK missing n")

     

       358
       +
       		}

     

       359
       +
       		// Lexicographic order: e, kty, n

     

       360
       +
       		canonical = map[string]string{

     

       361
       +
       			"e":   e,

     

       362
       +
       			"kty": kty,

     

       363
       +
       			"n":   n,

     

       364
       +
       		}

     

       365
       +
       	case "OKP":

     

       366
       +
       		crv, ok := jwk["crv"].(string)

     

       367
       +
       		if !ok {

     

       368
       +
       			return "", fmt.Errorf("OKP JWK missing crv")

     

       369
       +
       		}

     

       370
       +
       		x, ok := jwk["x"].(string)

     

       371
       +
       		if !ok {

     

       372
       +
       			return "", fmt.Errorf("OKP JWK missing x")

     

       373
       +
       		}

     

       374
       +
       		// Lexicographic order: crv, kty, x

     

       375
       +
       		canonical = map[string]string{

     

       376
       +
       			"crv": crv,

     

       377
       +
       			"kty": kty,

     

       378
       +
       			"x":   x,

     

       379
       +
       		}

     

       380
       +
       	default:

     

       381
       +
       		return "", fmt.Errorf("unsupported JWK key type: %s", kty)

     

       382
       +
       	}

     

       383
       +
       

     

       384
       +
       	// Serialize to JSON (Go's json.Marshal produces lexicographically ordered keys for map[string]string)

     

       385
       +
       	canonicalJSON, err := json.Marshal(canonical)

     

       386
       +
       	if err != nil {

     

       387
       +
       		return "", fmt.Errorf("failed to serialize canonical JWK: %w", err)

     

       388
       +
       	}

     

       389
       +
       

     

       390
       +
       	// SHA-256 hash

     

       391
       +
       	hash := sha256.Sum256(canonicalJSON)

     

       392
       +
       

     

       393
       +
       	// Base64url encode (no padding)

     

       394
       +
       	thumbprint := base64.RawURLEncoding.EncodeToString(hash[:])

     

       395
       +
       

     

       396
       +
       	return thumbprint, nil

     

       397
       +
       }

     

       398
       +
       

     

       399
       +
       // parseJWKToPublicKey parses a JWK map to a Go public key

     

       400
       +
       func parseJWKToPublicKey(jwkMap map[string]interface{}) (interface{}, error) {

     

       401
       +
       	// Convert map to JSON bytes for indigo's parser

     

       402
       +
       	jwkBytes, err := json.Marshal(jwkMap)

     

       403
       +
       	if err != nil {

     

       404
       +
       		return nil, fmt.Errorf("failed to serialize JWK: %w", err)

     

       405
       +
       	}

     

       406
       +
       

     

       407
       +
       	// Try to parse with indigo's crypto package

     

       408
       +
       	pubKey, err := indigoCrypto.ParsePublicJWKBytes(jwkBytes)

     

       409
       +
       	if err != nil {

     

       410
       +
       		return nil, fmt.Errorf("failed to parse JWK: %w", err)

     

       411
       +
       	}

     

       412
       +
       

     

       413
       +
       	// Convert indigo's PublicKey to Go's ecdsa.PublicKey

     

       414
       +
       	jwk, err := pubKey.JWK()

     

       415
       +
       	if err != nil {

     

       416
       +
       		return nil, fmt.Errorf("failed to get JWK from public key: %w", err)

     

       417
       +
       	}

     

       418
       +
       

     

       419
       +
       	// Use our existing conversion function

     

       420
       +
       	return atcryptoJWKToECDSAFromIndigoJWK(jwk)

     

       421
       +
       }

     

       422
       +
       

     

       423
       +
       // atcryptoJWKToECDSAFromIndigoJWK converts an indigo JWK to Go ecdsa.PublicKey

     

       424
       +
       func atcryptoJWKToECDSAFromIndigoJWK(jwk *indigoCrypto.JWK) (*ecdsa.PublicKey, error) {

     

       425
       +
       	if jwk.KeyType != "EC" {

     

       426
       +
       		return nil, fmt.Errorf("unsupported JWK key type: %s (expected EC)", jwk.KeyType)

     

       427
       +
       	}

     

       428
       +
       

     

       429
       +
       	xBytes, err := base64.RawURLEncoding.DecodeString(jwk.X)

     

       430
       +
       	if err != nil {

     

       431
       +
       		return nil, fmt.Errorf("invalid JWK X coordinate: %w", err)

     

       432
       +
       	}

     

       433
       +
       	yBytes, err := base64.RawURLEncoding.DecodeString(jwk.Y)

     

       434
       +
       	if err != nil {

     

       435
       +
       		return nil, fmt.Errorf("invalid JWK Y coordinate: %w", err)

     

       436
       +
       	}

     

       437
       +
       

     

       438
       +
       	var curve ecdsa.PublicKey

     

       439
       +
       	switch jwk.Curve {

     

       440
       +
       	case "P-256":

     

       441
       +
       		curve.Curve = ecdsaP256Curve()

     

       442
       +
       	case "P-384":

     

       443
       +
       		curve.Curve = ecdsaP384Curve()

     

       444
       +
       	case "P-521":

     

       445
       +
       		curve.Curve = ecdsaP521Curve()

     

       446
       +
       	default:

     

       447
       +
       		return nil, fmt.Errorf("unsupported curve: %s", jwk.Curve)

     

       448
       +
       	}

     

       449
       +
       

     

       450
       +
       	curve.X = new(big.Int).SetBytes(xBytes)

     

       451
       +
       	curve.Y = new(big.Int).SetBytes(yBytes)

     

       452
       +
       

     

       453
       +
       	return &curve, nil

     

       454
       +
       }

     

       455
       +
       

     

       456
       +
       // Helper functions for elliptic curves

     

       457
       +
       func ecdsaP256Curve() elliptic.Curve { return elliptic.P256() }

     

       458
       +
       func ecdsaP384Curve() elliptic.Curve { return elliptic.P384() }

     

       459
       +
       func ecdsaP521Curve() elliptic.Curve { return elliptic.P521() }

     

       460
       +
       

     

       461
       +
       // stripQueryFragment removes query and fragment from a URI

     

       462
       +
       func stripQueryFragment(uri string) string {

     

       463
       +
       	if idx := strings.Index(uri, "?"); idx != -1 {

     

       464
       +
       		uri = uri[:idx]

     

       465
       +
       	}

     

       466
       +
       	if idx := strings.Index(uri, "#"); idx != -1 {

     

       467
       +
       		uri = uri[:idx]

     

       468
       +
       	}

     

       469
       +
       	return uri

     

       470
       +
       }

     

       471
       +
       

     

       472
       +
       // ExtractCnfJkt extracts the cnf.jkt (confirmation key thumbprint) from JWT claims

     

       473
       +
       func ExtractCnfJkt(claims *Claims) (string, error) {

     

       474
       +
       	if claims.Confirmation == nil {

     

       475
       +
       		return "", fmt.Errorf("token missing cnf claim (no DPoP binding)")

     

       476
       +
       	}

     

       477
       +
       

     

       478
       +
       	jkt, ok := claims.Confirmation["jkt"].(string)

     

       479
       +
       	if !ok || jkt == "" {

     

       480
       +
       		return "", fmt.Errorf("token cnf claim missing jkt (DPoP key thumbprint)")

     

       481
       +
       	}

     

       482
       +
       

     

       483
       +
       	return jkt, nil

     

       484
       +
       }

+921

internal/atproto/auth/dpop_test.go

···

       1
       +
       package auth

     

       2
       +
       

     

       3
       +
       import (

     

       4
       +
       	"crypto/ecdsa"

     

       5
       +
       	"crypto/elliptic"

     

       6
       +
       	"crypto/rand"

     

       7
       +
       	"crypto/sha256"

     

       8
       +
       	"encoding/base64"

     

       9
       +
       	"encoding/json"

     

       10
       +
       	"strings"

     

       11
       +
       	"testing"

     

       12
       +
       	"time"

     

       13
       +
       

     

       14
       +
       	"github.com/golang-jwt/jwt/v5"

     

       15
       +
       	"github.com/google/uuid"

     

       16
       +
       )

     

       17
       +
       

     

       18
       +
       // === Test Helpers ===

     

       19
       +
       

     

       20
       +
       // testECKey holds a test ES256 key pair

     

       21
       +
       type testECKey struct {

     

       22
       +
       	privateKey *ecdsa.PrivateKey

     

       23
       +
       	publicKey  *ecdsa.PublicKey

     

       24
       +
       	jwk        map[string]interface{}

     

       25
       +
       	thumbprint string

     

       26
       +
       }

     

       27
       +
       

     

       28
       +
       // generateTestES256Key generates a test ES256 key pair and JWK

     

       29
       +
       func generateTestES256Key(t *testing.T) *testECKey {

     

       30
       +
       	t.Helper()

     

       31
       +
       

     

       32
       +
       	privateKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

     

       33
       +
       	if err != nil {

     

       34
       +
       		t.Fatalf("Failed to generate test key: %v", err)

     

       35
       +
       	}

     

       36
       +
       

     

       37
       +
       	// Encode public key coordinates as base64url

     

       38
       +
       	xBytes := privateKey.PublicKey.X.Bytes()

     

       39
       +
       	yBytes := privateKey.PublicKey.Y.Bytes()

     

       40
       +
       

     

       41
       +
       	// P-256 coordinates must be 32 bytes (pad if needed)

     

       42
       +
       	xBytes = padTo32Bytes(xBytes)

     

       43
       +
       	yBytes = padTo32Bytes(yBytes)

     

       44
       +
       

     

       45
       +
       	x := base64.RawURLEncoding.EncodeToString(xBytes)

     

       46
       +
       	y := base64.RawURLEncoding.EncodeToString(yBytes)

     

       47
       +
       

     

       48
       +
       	jwk := map[string]interface{}{

     

       49
       +
       		"kty": "EC",

     

       50
       +
       		"crv": "P-256",

     

       51
       +
       		"x":   x,

     

       52
       +
       		"y":   y,

     

       53
       +
       	}

     

       54
       +
       

     

       55
       +
       	// Calculate thumbprint

     

       56
       +
       	thumbprint, err := CalculateJWKThumbprint(jwk)

     

       57
       +
       	if err != nil {

     

       58
       +
       		t.Fatalf("Failed to calculate thumbprint: %v", err)

     

       59
       +
       	}

     

       60
       +
       

     

       61
       +
       	return &testECKey{

     

       62
       +
       		privateKey: privateKey,

     

       63
       +
       		publicKey:  &privateKey.PublicKey,

     

       64
       +
       		jwk:        jwk,

     

       65
       +
       		thumbprint: thumbprint,

     

       66
       +
       	}

     

       67
       +
       }

     

       68
       +
       

     

       69
       +
       // padTo32Bytes pads a byte slice to 32 bytes (required for P-256 coordinates)

     

       70
       +
       func padTo32Bytes(b []byte) []byte {

     

       71
       +
       	if len(b) >= 32 {

     

       72
       +
       		return b

     

       73
       +
       	}

     

       74
       +
       	padded := make([]byte, 32)

     

       75
       +
       	copy(padded[32-len(b):], b)

     

       76
       +
       	return padded

     

       77
       +
       }

     

       78
       +
       

     

       79
       +
       // createDPoPProof creates a DPoP proof JWT for testing

     

       80
       +
       func createDPoPProof(t *testing.T, key *testECKey, method, uri string, iat time.Time, jti string) string {

     

       81
       +
       	t.Helper()

     

       82
       +
       

     

       83
       +
       	claims := &DPoPClaims{

     

       84
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       85
       +
       			ID:       jti,

     

       86
       +
       			IssuedAt: jwt.NewNumericDate(iat),

     

       87
       +
       		},

     

       88
       +
       		HTTPMethod: method,

     

       89
       +
       		HTTPURI:    uri,

     

       90
       +
       	}

     

       91
       +
       

     

       92
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodES256, claims)

     

       93
       +
       	token.Header["typ"] = "dpop+jwt"

     

       94
       +
       	token.Header["jwk"] = key.jwk

     

       95
       +
       

     

       96
       +
       	tokenString, err := token.SignedString(key.privateKey)

     

       97
       +
       	if err != nil {

     

       98
       +
       		t.Fatalf("Failed to create DPoP proof: %v", err)

     

       99
       +
       	}

     

       100
       +
       

     

       101
       +
       	return tokenString

     

       102
       +
       }

     

       103
       +
       

     

       104
       +
       // === JWK Thumbprint Tests (RFC 7638) ===

     

       105
       +
       

     

       106
       +
       func TestCalculateJWKThumbprint_EC_P256(t *testing.T) {

     

       107
       +
       	// Test with known values from RFC 7638 Appendix A (adapted for P-256)

     

       108
       +
       	jwk := map[string]interface{}{

     

       109
       +
       		"kty": "EC",

     

       110
       +
       		"crv": "P-256",

     

       111
       +
       		"x":   "WKn-ZIGevcwGIyyrzFoZNBdaq9_TsqzGl96oc0CWuis",

     

       112
       +
       		"y":   "y77t-RvAHRKTsSGdIYUfweuOvwrvDD-Q3Hv5J0fSKbE",

     

       113
       +
       	}

     

       114
       +
       

     

       115
       +
       	thumbprint, err := CalculateJWKThumbprint(jwk)

     

       116
       +
       	if err != nil {

     

       117
       +
       		t.Fatalf("CalculateJWKThumbprint failed: %v", err)

     

       118
       +
       	}

     

       119
       +
       

     

       120
       +
       	if thumbprint == "" {

     

       121
       +
       		t.Error("Expected non-empty thumbprint")

     

       122
       +
       	}

     

       123
       +
       

     

       124
       +
       	// Verify it's valid base64url

     

       125
       +
       	_, err = base64.RawURLEncoding.DecodeString(thumbprint)

     

       126
       +
       	if err != nil {

     

       127
       +
       		t.Errorf("Thumbprint is not valid base64url: %v", err)

     

       128
       +
       	}

     

       129
       +
       

     

       130
       +
       	// Verify length (SHA-256 produces 32 bytes = 43 base64url chars)

     

       131
       +
       	if len(thumbprint) != 43 {

     

       132
       +
       		t.Errorf("Expected thumbprint length 43, got %d", len(thumbprint))

     

       133
       +
       	}

     

       134
       +
       }

     

       135
       +
       

     

       136
       +
       func TestCalculateJWKThumbprint_Deterministic(t *testing.T) {

     

       137
       +
       	// Same key should produce same thumbprint

     

       138
       +
       	jwk := map[string]interface{}{

     

       139
       +
       		"kty": "EC",

     

       140
       +
       		"crv": "P-256",

     

       141
       +
       		"x":   "test-x-coordinate",

     

       142
       +
       		"y":   "test-y-coordinate",

     

       143
       +
       	}

     

       144
       +
       

     

       145
       +
       	thumbprint1, err := CalculateJWKThumbprint(jwk)

     

       146
       +
       	if err != nil {

     

       147
       +
       		t.Fatalf("First CalculateJWKThumbprint failed: %v", err)

     

       148
       +
       	}

     

       149
       +
       

     

       150
       +
       	thumbprint2, err := CalculateJWKThumbprint(jwk)

     

       151
       +
       	if err != nil {

     

       152
       +
       		t.Fatalf("Second CalculateJWKThumbprint failed: %v", err)

     

       153
       +
       	}

     

       154
       +
       

     

       155
       +
       	if thumbprint1 != thumbprint2 {

     

       156
       +
       		t.Errorf("Thumbprints are not deterministic: %s != %s", thumbprint1, thumbprint2)

     

       157
       +
       	}

     

       158
       +
       }

     

       159
       +
       

     

       160
       +
       func TestCalculateJWKThumbprint_DifferentKeys(t *testing.T) {

     

       161
       +
       	// Different keys should produce different thumbprints

     

       162
       +
       	jwk1 := map[string]interface{}{

     

       163
       +
       		"kty": "EC",

     

       164
       +
       		"crv": "P-256",

     

       165
       +
       		"x":   "coordinate-x-1",

     

       166
       +
       		"y":   "coordinate-y-1",

     

       167
       +
       	}

     

       168
       +
       

     

       169
       +
       	jwk2 := map[string]interface{}{

     

       170
       +
       		"kty": "EC",

     

       171
       +
       		"crv": "P-256",

     

       172
       +
       		"x":   "coordinate-x-2",

     

       173
       +
       		"y":   "coordinate-y-2",

     

       174
       +
       	}

     

       175
       +
       

     

       176
       +
       	thumbprint1, err := CalculateJWKThumbprint(jwk1)

     

       177
       +
       	if err != nil {

     

       178
       +
       		t.Fatalf("First CalculateJWKThumbprint failed: %v", err)

     

       179
       +
       	}

     

       180
       +
       

     

       181
       +
       	thumbprint2, err := CalculateJWKThumbprint(jwk2)

     

       182
       +
       	if err != nil {

     

       183
       +
       		t.Fatalf("Second CalculateJWKThumbprint failed: %v", err)

     

       184
       +
       	}

     

       185
       +
       

     

       186
       +
       	if thumbprint1 == thumbprint2 {

     

       187
       +
       		t.Error("Different keys produced same thumbprint (collision)")

     

       188
       +
       	}

     

       189
       +
       }

     

       190
       +
       

     

       191
       +
       func TestCalculateJWKThumbprint_MissingKty(t *testing.T) {

     

       192
       +
       	jwk := map[string]interface{}{

     

       193
       +
       		"crv": "P-256",

     

       194
       +
       		"x":   "test-x",

     

       195
       +
       		"y":   "test-y",

     

       196
       +
       	}

     

       197
       +
       

     

       198
       +
       	_, err := CalculateJWKThumbprint(jwk)

     

       199
       +
       	if err == nil {

     

       200
       +
       		t.Error("Expected error for missing kty, got nil")

     

       201
       +
       	}

     

       202
       +
       	if err != nil && !contains(err.Error(), "missing kty") {

     

       203
       +
       		t.Errorf("Expected error about missing kty, got: %v", err)

     

       204
       +
       	}

     

       205
       +
       }

     

       206
       +
       

     

       207
       +
       func TestCalculateJWKThumbprint_EC_MissingCrv(t *testing.T) {

     

       208
       +
       	jwk := map[string]interface{}{

     

       209
       +
       		"kty": "EC",

     

       210
       +
       		"x":   "test-x",

     

       211
       +
       		"y":   "test-y",

     

       212
       +
       	}

     

       213
       +
       

     

       214
       +
       	_, err := CalculateJWKThumbprint(jwk)

     

       215
       +
       	if err == nil {

     

       216
       +
       		t.Error("Expected error for missing crv, got nil")

     

       217
       +
       	}

     

       218
       +
       	if err != nil && !contains(err.Error(), "missing crv") {

     

       219
       +
       		t.Errorf("Expected error about missing crv, got: %v", err)

     

       220
       +
       	}

     

       221
       +
       }

     

       222
       +
       

     

       223
       +
       func TestCalculateJWKThumbprint_EC_MissingX(t *testing.T) {

     

       224
       +
       	jwk := map[string]interface{}{

     

       225
       +
       		"kty": "EC",

     

       226
       +
       		"crv": "P-256",

     

       227
       +
       		"y":   "test-y",

     

       228
       +
       	}

     

       229
       +
       

     

       230
       +
       	_, err := CalculateJWKThumbprint(jwk)

     

       231
       +
       	if err == nil {

     

       232
       +
       		t.Error("Expected error for missing x, got nil")

     

       233
       +
       	}

     

       234
       +
       	if err != nil && !contains(err.Error(), "missing x") {

     

       235
       +
       		t.Errorf("Expected error about missing x, got: %v", err)

     

       236
       +
       	}

     

       237
       +
       }

     

       238
       +
       

     

       239
       +
       func TestCalculateJWKThumbprint_EC_MissingY(t *testing.T) {

     

       240
       +
       	jwk := map[string]interface{}{

     

       241
       +
       		"kty": "EC",

     

       242
       +
       		"crv": "P-256",

     

       243
       +
       		"x":   "test-x",

     

       244
       +
       	}

     

       245
       +
       

     

       246
       +
       	_, err := CalculateJWKThumbprint(jwk)

     

       247
       +
       	if err == nil {

     

       248
       +
       		t.Error("Expected error for missing y, got nil")

     

       249
       +
       	}

     

       250
       +
       	if err != nil && !contains(err.Error(), "missing y") {

     

       251
       +
       		t.Errorf("Expected error about missing y, got: %v", err)

     

       252
       +
       	}

     

       253
       +
       }

     

       254
       +
       

     

       255
       +
       func TestCalculateJWKThumbprint_RSA(t *testing.T) {

     

       256
       +
       	// Test RSA key thumbprint calculation

     

       257
       +
       	jwk := map[string]interface{}{

     

       258
       +
       		"kty": "RSA",

     

       259
       +
       		"e":   "AQAB",

     

       260
       +
       		"n":   "test-modulus",

     

       261
       +
       	}

     

       262
       +
       

     

       263
       +
       	thumbprint, err := CalculateJWKThumbprint(jwk)

     

       264
       +
       	if err != nil {

     

       265
       +
       		t.Fatalf("CalculateJWKThumbprint failed for RSA: %v", err)

     

       266
       +
       	}

     

       267
       +
       

     

       268
       +
       	if thumbprint == "" {

     

       269
       +
       		t.Error("Expected non-empty thumbprint for RSA key")

     

       270
       +
       	}

     

       271
       +
       }

     

       272
       +
       

     

       273
       +
       func TestCalculateJWKThumbprint_OKP(t *testing.T) {

     

       274
       +
       	// Test OKP (Octet Key Pair) thumbprint calculation

     

       275
       +
       	jwk := map[string]interface{}{

     

       276
       +
       		"kty": "OKP",

     

       277
       +
       		"crv": "Ed25519",

     

       278
       +
       		"x":   "test-x-coordinate",

     

       279
       +
       	}

     

       280
       +
       

     

       281
       +
       	thumbprint, err := CalculateJWKThumbprint(jwk)

     

       282
       +
       	if err != nil {

     

       283
       +
       		t.Fatalf("CalculateJWKThumbprint failed for OKP: %v", err)

     

       284
       +
       	}

     

       285
       +
       

     

       286
       +
       	if thumbprint == "" {

     

       287
       +
       		t.Error("Expected non-empty thumbprint for OKP key")

     

       288
       +
       	}

     

       289
       +
       }

     

       290
       +
       

     

       291
       +
       func TestCalculateJWKThumbprint_UnsupportedKeyType(t *testing.T) {

     

       292
       +
       	jwk := map[string]interface{}{

     

       293
       +
       		"kty": "UNKNOWN",

     

       294
       +
       	}

     

       295
       +
       

     

       296
       +
       	_, err := CalculateJWKThumbprint(jwk)

     

       297
       +
       	if err == nil {

     

       298
       +
       		t.Error("Expected error for unsupported key type, got nil")

     

       299
       +
       	}

     

       300
       +
       	if err != nil && !contains(err.Error(), "unsupported JWK key type") {

     

       301
       +
       		t.Errorf("Expected error about unsupported key type, got: %v", err)

     

       302
       +
       	}

     

       303
       +
       }

     

       304
       +
       

     

       305
       +
       func TestCalculateJWKThumbprint_CanonicalJSON(t *testing.T) {

     

       306
       +
       	// RFC 7638 requires lexicographic ordering of keys in canonical JSON

     

       307
       +
       	// This test verifies that the canonical JSON is correctly ordered

     

       308
       +
       

     

       309
       +
       	jwk := map[string]interface{}{

     

       310
       +
       		"kty": "EC",

     

       311
       +
       		"crv": "P-256",

     

       312
       +
       		"x":   "x-coord",

     

       313
       +
       		"y":   "y-coord",

     

       314
       +
       	}

     

       315
       +
       

     

       316
       +
       	// The canonical JSON should be: {"crv":"P-256","kty":"EC","x":"x-coord","y":"y-coord"}

     

       317
       +
       	// (lexicographically ordered: crv, kty, x, y)

     

       318
       +
       

     

       319
       +
       	canonical := map[string]string{

     

       320
       +
       		"crv": "P-256",

     

       321
       +
       		"kty": "EC",

     

       322
       +
       		"x":   "x-coord",

     

       323
       +
       		"y":   "y-coord",

     

       324
       +
       	}

     

       325
       +
       

     

       326
       +
       	canonicalJSON, err := json.Marshal(canonical)

     

       327
       +
       	if err != nil {

     

       328
       +
       		t.Fatalf("Failed to marshal canonical JSON: %v", err)

     

       329
       +
       	}

     

       330
       +
       

     

       331
       +
       	expectedHash := sha256.Sum256(canonicalJSON)

     

       332
       +
       	expectedThumbprint := base64.RawURLEncoding.EncodeToString(expectedHash[:])

     

       333
       +
       

     

       334
       +
       	actualThumbprint, err := CalculateJWKThumbprint(jwk)

     

       335
       +
       	if err != nil {

     

       336
       +
       		t.Fatalf("CalculateJWKThumbprint failed: %v", err)

     

       337
       +
       	}

     

       338
       +
       

     

       339
       +
       	if actualThumbprint != expectedThumbprint {

     

       340
       +
       		t.Errorf("Thumbprint doesn't match expected canonical JSON hash\nExpected: %s\nGot: %s",

     

       341
       +
       			expectedThumbprint, actualThumbprint)

     

       342
       +
       	}

     

       343
       +
       }

     

       344
       +
       

     

       345
       +
       // === DPoP Proof Verification Tests ===

     

       346
       +
       

     

       347
       +
       func TestVerifyDPoPProof_Valid(t *testing.T) {

     

       348
       +
       	verifier := NewDPoPVerifier()

     

       349
       +
       	key := generateTestES256Key(t)

     

       350
       +
       

     

       351
       +
       	method := "POST"

     

       352
       +
       	uri := "https://api.example.com/resource"

     

       353
       +
       	iat := time.Now()

     

       354
       +
       	jti := uuid.New().String()

     

       355
       +
       

     

       356
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       357
       +
       

     

       358
       +
       	result, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       359
       +
       	if err != nil {

     

       360
       +
       		t.Fatalf("VerifyDPoPProof failed for valid proof: %v", err)

     

       361
       +
       	}

     

       362
       +
       

     

       363
       +
       	if result == nil {

     

       364
       +
       		t.Fatal("Expected non-nil proof result")

     

       365
       +
       	}

     

       366
       +
       

     

       367
       +
       	if result.Claims.HTTPMethod != method {

     

       368
       +
       		t.Errorf("Expected method %s, got %s", method, result.Claims.HTTPMethod)

     

       369
       +
       	}

     

       370
       +
       

     

       371
       +
       	if result.Claims.HTTPURI != uri {

     

       372
       +
       		t.Errorf("Expected URI %s, got %s", uri, result.Claims.HTTPURI)

     

       373
       +
       	}

     

       374
       +
       

     

       375
       +
       	if result.Claims.ID != jti {

     

       376
       +
       		t.Errorf("Expected jti %s, got %s", jti, result.Claims.ID)

     

       377
       +
       	}

     

       378
       +
       

     

       379
       +
       	if result.Thumbprint != key.thumbprint {

     

       380
       +
       		t.Errorf("Expected thumbprint %s, got %s", key.thumbprint, result.Thumbprint)

     

       381
       +
       	}

     

       382
       +
       }

     

       383
       +
       

     

       384
       +
       func TestVerifyDPoPProof_InvalidSignature(t *testing.T) {

     

       385
       +
       	verifier := NewDPoPVerifier()

     

       386
       +
       	key := generateTestES256Key(t)

     

       387
       +
       	wrongKey := generateTestES256Key(t)

     

       388
       +
       

     

       389
       +
       	method := "POST"

     

       390
       +
       	uri := "https://api.example.com/resource"

     

       391
       +
       	iat := time.Now()

     

       392
       +
       	jti := uuid.New().String()

     

       393
       +
       

     

       394
       +
       	// Create proof with one key

     

       395
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       396
       +
       

     

       397
       +
       	// Parse and modify to use wrong key's JWK in header (signature won't match)

     

       398
       +
       	parts := splitJWT(proof)

     

       399
       +
       	header := parseJWTHeader(t, parts[0])

     

       400
       +
       	header["jwk"] = wrongKey.jwk

     

       401
       +
       	modifiedHeader := encodeJSON(t, header)

     

       402
       +
       	tamperedProof := modifiedHeader + "." + parts[1] + "." + parts[2]

     

       403
       +
       

     

       404
       +
       	_, err := verifier.VerifyDPoPProof(tamperedProof, method, uri)

     

       405
       +
       	if err == nil {

     

       406
       +
       		t.Error("Expected error for invalid signature, got nil")

     

       407
       +
       	}

     

       408
       +
       	if err != nil && !contains(err.Error(), "signature verification failed") {

     

       409
       +
       		t.Errorf("Expected signature verification error, got: %v", err)

     

       410
       +
       	}

     

       411
       +
       }

     

       412
       +
       

     

       413
       +
       func TestVerifyDPoPProof_WrongHTTPMethod(t *testing.T) {

     

       414
       +
       	verifier := NewDPoPVerifier()

     

       415
       +
       	key := generateTestES256Key(t)

     

       416
       +
       

     

       417
       +
       	method := "POST"

     

       418
       +
       	wrongMethod := "GET"

     

       419
       +
       	uri := "https://api.example.com/resource"

     

       420
       +
       	iat := time.Now()

     

       421
       +
       	jti := uuid.New().String()

     

       422
       +
       

     

       423
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       424
       +
       

     

       425
       +
       	_, err := verifier.VerifyDPoPProof(proof, wrongMethod, uri)

     

       426
       +
       	if err == nil {

     

       427
       +
       		t.Error("Expected error for HTTP method mismatch, got nil")

     

       428
       +
       	}

     

       429
       +
       	if err != nil && !contains(err.Error(), "htm mismatch") {

     

       430
       +
       		t.Errorf("Expected htm mismatch error, got: %v", err)

     

       431
       +
       	}

     

       432
       +
       }

     

       433
       +
       

     

       434
       +
       func TestVerifyDPoPProof_WrongURI(t *testing.T) {

     

       435
       +
       	verifier := NewDPoPVerifier()

     

       436
       +
       	key := generateTestES256Key(t)

     

       437
       +
       

     

       438
       +
       	method := "POST"

     

       439
       +
       	uri := "https://api.example.com/resource"

     

       440
       +
       	wrongURI := "https://api.example.com/different"

     

       441
       +
       	iat := time.Now()

     

       442
       +
       	jti := uuid.New().String()

     

       443
       +
       

     

       444
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       445
       +
       

     

       446
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, wrongURI)

     

       447
       +
       	if err == nil {

     

       448
       +
       		t.Error("Expected error for URI mismatch, got nil")

     

       449
       +
       	}

     

       450
       +
       	if err != nil && !contains(err.Error(), "htu mismatch") {

     

       451
       +
       		t.Errorf("Expected htu mismatch error, got: %v", err)

     

       452
       +
       	}

     

       453
       +
       }

     

       454
       +
       

     

       455
       +
       func TestVerifyDPoPProof_URIWithQuery(t *testing.T) {

     

       456
       +
       	// URI comparison should strip query and fragment

     

       457
       +
       	verifier := NewDPoPVerifier()

     

       458
       +
       	key := generateTestES256Key(t)

     

       459
       +
       

     

       460
       +
       	method := "POST"

     

       461
       +
       	baseURI := "https://api.example.com/resource"

     

       462
       +
       	uriWithQuery := baseURI + "?param=value"

     

       463
       +
       	iat := time.Now()

     

       464
       +
       	jti := uuid.New().String()

     

       465
       +
       

     

       466
       +
       	proof := createDPoPProof(t, key, method, baseURI, iat, jti)

     

       467
       +
       

     

       468
       +
       	// Should succeed because query is stripped

     

       469
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, uriWithQuery)

     

       470
       +
       	if err != nil {

     

       471
       +
       		t.Fatalf("VerifyDPoPProof failed for URI with query: %v", err)

     

       472
       +
       	}

     

       473
       +
       }

     

       474
       +
       

     

       475
       +
       func TestVerifyDPoPProof_URIWithFragment(t *testing.T) {

     

       476
       +
       	// URI comparison should strip query and fragment

     

       477
       +
       	verifier := NewDPoPVerifier()

     

       478
       +
       	key := generateTestES256Key(t)

     

       479
       +
       

     

       480
       +
       	method := "POST"

     

       481
       +
       	baseURI := "https://api.example.com/resource"

     

       482
       +
       	uriWithFragment := baseURI + "#section"

     

       483
       +
       	iat := time.Now()

     

       484
       +
       	jti := uuid.New().String()

     

       485
       +
       

     

       486
       +
       	proof := createDPoPProof(t, key, method, baseURI, iat, jti)

     

       487
       +
       

     

       488
       +
       	// Should succeed because fragment is stripped

     

       489
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, uriWithFragment)

     

       490
       +
       	if err != nil {

     

       491
       +
       		t.Fatalf("VerifyDPoPProof failed for URI with fragment: %v", err)

     

       492
       +
       	}

     

       493
       +
       }

     

       494
       +
       

     

       495
       +
       func TestVerifyDPoPProof_ExpiredProof(t *testing.T) {

     

       496
       +
       	verifier := NewDPoPVerifier()

     

       497
       +
       	key := generateTestES256Key(t)

     

       498
       +
       

     

       499
       +
       	method := "POST"

     

       500
       +
       	uri := "https://api.example.com/resource"

     

       501
       +
       	// Proof issued 10 minutes ago (exceeds default MaxProofAge of 5 minutes)

     

       502
       +
       	iat := time.Now().Add(-10 * time.Minute)

     

       503
       +
       	jti := uuid.New().String()

     

       504
       +
       

     

       505
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       506
       +
       

     

       507
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       508
       +
       	if err == nil {

     

       509
       +
       		t.Error("Expected error for expired proof, got nil")

     

       510
       +
       	}

     

       511
       +
       	if err != nil && !contains(err.Error(), "too old") {

     

       512
       +
       		t.Errorf("Expected 'too old' error, got: %v", err)

     

       513
       +
       	}

     

       514
       +
       }

     

       515
       +
       

     

       516
       +
       func TestVerifyDPoPProof_FutureProof(t *testing.T) {

     

       517
       +
       	verifier := NewDPoPVerifier()

     

       518
       +
       	key := generateTestES256Key(t)

     

       519
       +
       

     

       520
       +
       	method := "POST"

     

       521
       +
       	uri := "https://api.example.com/resource"

     

       522
       +
       	// Proof issued 1 minute in the future (exceeds MaxClockSkew)

     

       523
       +
       	iat := time.Now().Add(1 * time.Minute)

     

       524
       +
       	jti := uuid.New().String()

     

       525
       +
       

     

       526
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       527
       +
       

     

       528
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       529
       +
       	if err == nil {

     

       530
       +
       		t.Error("Expected error for future proof, got nil")

     

       531
       +
       	}

     

       532
       +
       	if err != nil && !contains(err.Error(), "in the future") {

     

       533
       +
       		t.Errorf("Expected 'in the future' error, got: %v", err)

     

       534
       +
       	}

     

       535
       +
       }

     

       536
       +
       

     

       537
       +
       func TestVerifyDPoPProof_WithinClockSkew(t *testing.T) {

     

       538
       +
       	verifier := NewDPoPVerifier()

     

       539
       +
       	key := generateTestES256Key(t)

     

       540
       +
       

     

       541
       +
       	method := "POST"

     

       542
       +
       	uri := "https://api.example.com/resource"

     

       543
       +
       	// Proof issued 15 seconds in the future (within MaxClockSkew of 30s)

     

       544
       +
       	iat := time.Now().Add(15 * time.Second)

     

       545
       +
       	jti := uuid.New().String()

     

       546
       +
       

     

       547
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       548
       +
       

     

       549
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       550
       +
       	if err != nil {

     

       551
       +
       		t.Fatalf("VerifyDPoPProof failed for proof within clock skew: %v", err)

     

       552
       +
       	}

     

       553
       +
       }

     

       554
       +
       

     

       555
       +
       func TestVerifyDPoPProof_MissingJti(t *testing.T) {

     

       556
       +
       	verifier := NewDPoPVerifier()

     

       557
       +
       	key := generateTestES256Key(t)

     

       558
       +
       

     

       559
       +
       	method := "POST"

     

       560
       +
       	uri := "https://api.example.com/resource"

     

       561
       +
       	iat := time.Now()

     

       562
       +
       

     

       563
       +
       	claims := &DPoPClaims{

     

       564
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       565
       +
       			// No ID (jti)

     

       566
       +
       			IssuedAt: jwt.NewNumericDate(iat),

     

       567
       +
       		},

     

       568
       +
       		HTTPMethod: method,

     

       569
       +
       		HTTPURI:    uri,

     

       570
       +
       	}

     

       571
       +
       

     

       572
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodES256, claims)

     

       573
       +
       	token.Header["typ"] = "dpop+jwt"

     

       574
       +
       	token.Header["jwk"] = key.jwk

     

       575
       +
       

     

       576
       +
       	proof, err := token.SignedString(key.privateKey)

     

       577
       +
       	if err != nil {

     

       578
       +
       		t.Fatalf("Failed to create test proof: %v", err)

     

       579
       +
       	}

     

       580
       +
       

     

       581
       +
       	_, err = verifier.VerifyDPoPProof(proof, method, uri)

     

       582
       +
       	if err == nil {

     

       583
       +
       		t.Error("Expected error for missing jti, got nil")

     

       584
       +
       	}

     

       585
       +
       	if err != nil && !contains(err.Error(), "missing jti") {

     

       586
       +
       		t.Errorf("Expected missing jti error, got: %v", err)

     

       587
       +
       	}

     

       588
       +
       }

     

       589
       +
       

     

       590
       +
       func TestVerifyDPoPProof_MissingTypHeader(t *testing.T) {

     

       591
       +
       	verifier := NewDPoPVerifier()

     

       592
       +
       	key := generateTestES256Key(t)

     

       593
       +
       

     

       594
       +
       	method := "POST"

     

       595
       +
       	uri := "https://api.example.com/resource"

     

       596
       +
       	iat := time.Now()

     

       597
       +
       	jti := uuid.New().String()

     

       598
       +
       

     

       599
       +
       	claims := &DPoPClaims{

     

       600
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       601
       +
       			ID:       jti,

     

       602
       +
       			IssuedAt: jwt.NewNumericDate(iat),

     

       603
       +
       		},

     

       604
       +
       		HTTPMethod: method,

     

       605
       +
       		HTTPURI:    uri,

     

       606
       +
       	}

     

       607
       +
       

     

       608
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodES256, claims)

     

       609
       +
       	// Don't set typ header

     

       610
       +
       	token.Header["jwk"] = key.jwk

     

       611
       +
       

     

       612
       +
       	proof, err := token.SignedString(key.privateKey)

     

       613
       +
       	if err != nil {

     

       614
       +
       		t.Fatalf("Failed to create test proof: %v", err)

     

       615
       +
       	}

     

       616
       +
       

     

       617
       +
       	_, err = verifier.VerifyDPoPProof(proof, method, uri)

     

       618
       +
       	if err == nil {

     

       619
       +
       		t.Error("Expected error for missing typ header, got nil")

     

       620
       +
       	}

     

       621
       +
       	if err != nil && !contains(err.Error(), "typ must be 'dpop+jwt'") {

     

       622
       +
       		t.Errorf("Expected typ header error, got: %v", err)

     

       623
       +
       	}

     

       624
       +
       }

     

       625
       +
       

     

       626
       +
       func TestVerifyDPoPProof_WrongTypHeader(t *testing.T) {

     

       627
       +
       	verifier := NewDPoPVerifier()

     

       628
       +
       	key := generateTestES256Key(t)

     

       629
       +
       

     

       630
       +
       	method := "POST"

     

       631
       +
       	uri := "https://api.example.com/resource"

     

       632
       +
       	iat := time.Now()

     

       633
       +
       	jti := uuid.New().String()

     

       634
       +
       

     

       635
       +
       	claims := &DPoPClaims{

     

       636
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       637
       +
       			ID:       jti,

     

       638
       +
       			IssuedAt: jwt.NewNumericDate(iat),

     

       639
       +
       		},

     

       640
       +
       		HTTPMethod: method,

     

       641
       +
       		HTTPURI:    uri,

     

       642
       +
       	}

     

       643
       +
       

     

       644
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodES256, claims)

     

       645
       +
       	token.Header["typ"] = "JWT" // Wrong typ

     

       646
       +
       	token.Header["jwk"] = key.jwk

     

       647
       +
       

     

       648
       +
       	proof, err := token.SignedString(key.privateKey)

     

       649
       +
       	if err != nil {

     

       650
       +
       		t.Fatalf("Failed to create test proof: %v", err)

     

       651
       +
       	}

     

       652
       +
       

     

       653
       +
       	_, err = verifier.VerifyDPoPProof(proof, method, uri)

     

       654
       +
       	if err == nil {

     

       655
       +
       		t.Error("Expected error for wrong typ header, got nil")

     

       656
       +
       	}

     

       657
       +
       	if err != nil && !contains(err.Error(), "typ must be 'dpop+jwt'") {

     

       658
       +
       		t.Errorf("Expected typ header error, got: %v", err)

     

       659
       +
       	}

     

       660
       +
       }

     

       661
       +
       

     

       662
       +
       func TestVerifyDPoPProof_MissingJWK(t *testing.T) {

     

       663
       +
       	verifier := NewDPoPVerifier()

     

       664
       +
       	key := generateTestES256Key(t)

     

       665
       +
       

     

       666
       +
       	method := "POST"

     

       667
       +
       	uri := "https://api.example.com/resource"

     

       668
       +
       	iat := time.Now()

     

       669
       +
       	jti := uuid.New().String()

     

       670
       +
       

     

       671
       +
       	claims := &DPoPClaims{

     

       672
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       673
       +
       			ID:       jti,

     

       674
       +
       			IssuedAt: jwt.NewNumericDate(iat),

     

       675
       +
       		},

     

       676
       +
       		HTTPMethod: method,

     

       677
       +
       		HTTPURI:    uri,

     

       678
       +
       	}

     

       679
       +
       

     

       680
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodES256, claims)

     

       681
       +
       	token.Header["typ"] = "dpop+jwt"

     

       682
       +
       	// Don't include JWK

     

       683
       +
       

     

       684
       +
       	proof, err := token.SignedString(key.privateKey)

     

       685
       +
       	if err != nil {

     

       686
       +
       		t.Fatalf("Failed to create test proof: %v", err)

     

       687
       +
       	}

     

       688
       +
       

     

       689
       +
       	_, err = verifier.VerifyDPoPProof(proof, method, uri)

     

       690
       +
       	if err == nil {

     

       691
       +
       		t.Error("Expected error for missing jwk header, got nil")

     

       692
       +
       	}

     

       693
       +
       	if err != nil && !contains(err.Error(), "missing jwk") {

     

       694
       +
       		t.Errorf("Expected missing jwk error, got: %v", err)

     

       695
       +
       	}

     

       696
       +
       }

     

       697
       +
       

     

       698
       +
       func TestVerifyDPoPProof_CustomTimeSettings(t *testing.T) {

     

       699
       +
       	verifier := &DPoPVerifier{

     

       700
       +
       		MaxClockSkew: 1 * time.Minute,

     

       701
       +
       		MaxProofAge:  10 * time.Minute,

     

       702
       +
       	}

     

       703
       +
       	key := generateTestES256Key(t)

     

       704
       +
       

     

       705
       +
       	method := "POST"

     

       706
       +
       	uri := "https://api.example.com/resource"

     

       707
       +
       	// Proof issued 50 seconds in the future (within custom MaxClockSkew)

     

       708
       +
       	iat := time.Now().Add(50 * time.Second)

     

       709
       +
       	jti := uuid.New().String()

     

       710
       +
       

     

       711
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       712
       +
       

     

       713
       +
       	_, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       714
       +
       	if err != nil {

     

       715
       +
       		t.Fatalf("VerifyDPoPProof failed with custom time settings: %v", err)

     

       716
       +
       	}

     

       717
       +
       }

     

       718
       +
       

     

       719
       +
       func TestVerifyDPoPProof_HTTPMethodCaseInsensitive(t *testing.T) {

     

       720
       +
       	// HTTP method comparison should be case-insensitive per spec

     

       721
       +
       	verifier := NewDPoPVerifier()

     

       722
       +
       	key := generateTestES256Key(t)

     

       723
       +
       

     

       724
       +
       	method := "post"

     

       725
       +
       	uri := "https://api.example.com/resource"

     

       726
       +
       	iat := time.Now()

     

       727
       +
       	jti := uuid.New().String()

     

       728
       +
       

     

       729
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       730
       +
       

     

       731
       +
       	// Verify with uppercase method

     

       732
       +
       	_, err := verifier.VerifyDPoPProof(proof, "POST", uri)

     

       733
       +
       	if err != nil {

     

       734
       +
       		t.Fatalf("VerifyDPoPProof failed for case-insensitive method: %v", err)

     

       735
       +
       	}

     

       736
       +
       }

     

       737
       +
       

     

       738
       +
       // === Token Binding Verification Tests ===

     

       739
       +
       

     

       740
       +
       func TestVerifyTokenBinding_Matching(t *testing.T) {

     

       741
       +
       	verifier := NewDPoPVerifier()

     

       742
       +
       	key := generateTestES256Key(t)

     

       743
       +
       

     

       744
       +
       	method := "POST"

     

       745
       +
       	uri := "https://api.example.com/resource"

     

       746
       +
       	iat := time.Now()

     

       747
       +
       	jti := uuid.New().String()

     

       748
       +
       

     

       749
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       750
       +
       

     

       751
       +
       	result, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       752
       +
       	if err != nil {

     

       753
       +
       		t.Fatalf("VerifyDPoPProof failed: %v", err)

     

       754
       +
       	}

     

       755
       +
       

     

       756
       +
       	// Verify token binding with matching thumbprint

     

       757
       +
       	err = verifier.VerifyTokenBinding(result, key.thumbprint)

     

       758
       +
       	if err != nil {

     

       759
       +
       		t.Fatalf("VerifyTokenBinding failed for matching thumbprint: %v", err)

     

       760
       +
       	}

     

       761
       +
       }

     

       762
       +
       

     

       763
       +
       func TestVerifyTokenBinding_Mismatch(t *testing.T) {

     

       764
       +
       	verifier := NewDPoPVerifier()

     

       765
       +
       	key := generateTestES256Key(t)

     

       766
       +
       	wrongKey := generateTestES256Key(t)

     

       767
       +
       

     

       768
       +
       	method := "POST"

     

       769
       +
       	uri := "https://api.example.com/resource"

     

       770
       +
       	iat := time.Now()

     

       771
       +
       	jti := uuid.New().String()

     

       772
       +
       

     

       773
       +
       	proof := createDPoPProof(t, key, method, uri, iat, jti)

     

       774
       +
       

     

       775
       +
       	result, err := verifier.VerifyDPoPProof(proof, method, uri)

     

       776
       +
       	if err != nil {

     

       777
       +
       		t.Fatalf("VerifyDPoPProof failed: %v", err)

     

       778
       +
       	}

     

       779
       +
       

     

       780
       +
       	// Verify token binding with wrong thumbprint

     

       781
       +
       	err = verifier.VerifyTokenBinding(result, wrongKey.thumbprint)

     

       782
       +
       	if err == nil {

     

       783
       +
       		t.Error("Expected error for thumbprint mismatch, got nil")

     

       784
       +
       	}

     

       785
       +
       	if err != nil && !contains(err.Error(), "thumbprint mismatch") {

     

       786
       +
       		t.Errorf("Expected thumbprint mismatch error, got: %v", err)

     

       787
       +
       	}

     

       788
       +
       }

     

       789
       +
       

     

       790
       +
       // === ExtractCnfJkt Tests ===

     

       791
       +
       

     

       792
       +
       func TestExtractCnfJkt_Valid(t *testing.T) {

     

       793
       +
       	expectedJkt := "test-thumbprint-123"

     

       794
       +
       	claims := &Claims{

     

       795
       +
       		Confirmation: map[string]interface{}{

     

       796
       +
       			"jkt": expectedJkt,

     

       797
       +
       		},

     

       798
       +
       	}

     

       799
       +
       

     

       800
       +
       	jkt, err := ExtractCnfJkt(claims)

     

       801
       +
       	if err != nil {

     

       802
       +
       		t.Fatalf("ExtractCnfJkt failed for valid claims: %v", err)

     

       803
       +
       	}

     

       804
       +
       

     

       805
       +
       	if jkt != expectedJkt {

     

       806
       +
       		t.Errorf("Expected jkt %s, got %s", expectedJkt, jkt)

     

       807
       +
       	}

     

       808
       +
       }

     

       809
       +
       

     

       810
       +
       func TestExtractCnfJkt_MissingCnf(t *testing.T) {

     

       811
       +
       	claims := &Claims{

     

       812
       +
       		// No Confirmation

     

       813
       +
       	}

     

       814
       +
       

     

       815
       +
       	_, err := ExtractCnfJkt(claims)

     

       816
       +
       	if err == nil {

     

       817
       +
       		t.Error("Expected error for missing cnf, got nil")

     

       818
       +
       	}

     

       819
       +
       	if err != nil && !contains(err.Error(), "missing cnf claim") {

     

       820
       +
       		t.Errorf("Expected missing cnf error, got: %v", err)

     

       821
       +
       	}

     

       822
       +
       }

     

       823
       +
       

     

       824
       +
       func TestExtractCnfJkt_NilCnf(t *testing.T) {

     

       825
       +
       	claims := &Claims{

     

       826
       +
       		Confirmation: nil,

     

       827
       +
       	}

     

       828
       +
       

     

       829
       +
       	_, err := ExtractCnfJkt(claims)

     

       830
       +
       	if err == nil {

     

       831
       +
       		t.Error("Expected error for nil cnf, got nil")

     

       832
       +
       	}

     

       833
       +
       	if err != nil && !contains(err.Error(), "missing cnf claim") {

     

       834
       +
       		t.Errorf("Expected missing cnf error, got: %v", err)

     

       835
       +
       	}

     

       836
       +
       }

     

       837
       +
       

     

       838
       +
       func TestExtractCnfJkt_MissingJkt(t *testing.T) {

     

       839
       +
       	claims := &Claims{

     

       840
       +
       		Confirmation: map[string]interface{}{

     

       841
       +
       			"other": "value",

     

       842
       +
       		},

     

       843
       +
       	}

     

       844
       +
       

     

       845
       +
       	_, err := ExtractCnfJkt(claims)

     

       846
       +
       	if err == nil {

     

       847
       +
       		t.Error("Expected error for missing jkt, got nil")

     

       848
       +
       	}

     

       849
       +
       	if err != nil && !contains(err.Error(), "missing jkt") {

     

       850
       +
       		t.Errorf("Expected missing jkt error, got: %v", err)

     

       851
       +
       	}

     

       852
       +
       }

     

       853
       +
       

     

       854
       +
       func TestExtractCnfJkt_EmptyJkt(t *testing.T) {

     

       855
       +
       	claims := &Claims{

     

       856
       +
       		Confirmation: map[string]interface{}{

     

       857
       +
       			"jkt": "",

     

       858
       +
       		},

     

       859
       +
       	}

     

       860
       +
       

     

       861
       +
       	_, err := ExtractCnfJkt(claims)

     

       862
       +
       	if err == nil {

     

       863
       +
       		t.Error("Expected error for empty jkt, got nil")

     

       864
       +
       	}

     

       865
       +
       	if err != nil && !contains(err.Error(), "missing jkt") {

     

       866
       +
       		t.Errorf("Expected missing jkt error, got: %v", err)

     

       867
       +
       	}

     

       868
       +
       }

     

       869
       +
       

     

       870
       +
       func TestExtractCnfJkt_WrongType(t *testing.T) {

     

       871
       +
       	claims := &Claims{

     

       872
       +
       		Confirmation: map[string]interface{}{

     

       873
       +
       			"jkt": 123, // Not a string

     

       874
       +
       		},

     

       875
       +
       	}

     

       876
       +
       

     

       877
       +
       	_, err := ExtractCnfJkt(claims)

     

       878
       +
       	if err == nil {

     

       879
       +
       		t.Error("Expected error for wrong type jkt, got nil")

     

       880
       +
       	}

     

       881
       +
       	if err != nil && !contains(err.Error(), "missing jkt") {

     

       882
       +
       		t.Errorf("Expected missing jkt error, got: %v", err)

     

       883
       +
       	}

     

       884
       +
       }

     

       885
       +
       

     

       886
       +
       // === Helper Functions for Tests ===

     

       887
       +
       

     

       888
       +
       // splitJWT splits a JWT into its three parts

     

       889
       +
       func splitJWT(token string) []string {

     

       890
       +
       	return []string{

     

       891
       +
       		token[:strings.IndexByte(token, '.')],

     

       892
       +
       		token[strings.IndexByte(token, '.')+1 : strings.LastIndexByte(token, '.')],

     

       893
       +
       		token[strings.LastIndexByte(token, '.')+1:],

     

       894
       +
       	}

     

       895
       +
       }

     

       896
       +
       

     

       897
       +
       // parseJWTHeader parses a base64url-encoded JWT header

     

       898
       +
       func parseJWTHeader(t *testing.T, encoded string) map[string]interface{} {

     

       899
       +
       	t.Helper()

     

       900
       +
       	decoded, err := base64.RawURLEncoding.DecodeString(encoded)

     

       901
       +
       	if err != nil {

     

       902
       +
       		t.Fatalf("Failed to decode header: %v", err)

     

       903
       +
       	}

     

       904
       +
       

     

       905
       +
       	var header map[string]interface{}

     

       906
       +
       	if err := json.Unmarshal(decoded, &header); err != nil {

     

       907
       +
       		t.Fatalf("Failed to unmarshal header: %v", err)

     

       908
       +
       	}

     

       909
       +
       

     

       910
       +
       	return header

     

       911
       +
       }

     

       912
       +
       

     

       913
       +
       // encodeJSON encodes a value to base64url-encoded JSON

     

       914
       +
       func encodeJSON(t *testing.T, v interface{}) string {

     

       915
       +
       	t.Helper()

     

       916
       +
       	data, err := json.Marshal(v)

     

       917
       +
       	if err != nil {

     

       918
       +
       		t.Fatalf("Failed to marshal JSON: %v", err)

     

       919
       +
       	}

     

       920
       +
       	return base64.RawURLEncoding.EncodeToString(data)

     

       921
       +
       }

+148 -6

internal/api/middleware/auth.go

···

       3
        
       import (

     

       4
        
       	"Coves/internal/atproto/auth"

     

       5
        
       	"context"

     

       0
        
       
     

       6
        
       	"log"

     

       7
        
       	"net/http"

     

       8
        
       	"strings"

     
···

       15
        
       	UserDIDKey      contextKey = "user_did"

     

       16
        
       	JWTClaimsKey    contextKey = "jwt_claims"

     

       17
        
       	UserAccessToken contextKey = "user_access_token"

     

       0
        
       
     

       18
        
       )

     

       19
        
       

     

       20
        
       // AtProtoAuthMiddleware enforces atProto OAuth authentication for protected routes

     

       21
        
       // Validates JWT Bearer tokens from the Authorization header

     

       0
        
       
     

       22
        
       type AtProtoAuthMiddleware struct {

     

       23
       -
       	jwksFetcher auth.JWKSFetcher

     

       24
       -
       	skipVerify  bool // For Phase 1 testing only

     

       0
        
       
     

       25
        
       }

     

       26
        
       

     

       27
        
       // NewAtProtoAuthMiddleware creates a new atProto auth middleware

     

       28
        
       // skipVerify: if true, only parses JWT without signature verification (Phase 1)

     

       29
        
       //

     

       30
        
       //	if false, performs full signature verification (Phase 2)

     

       0
        
       
     

       0
        
       
     

       31
        
       func NewAtProtoAuthMiddleware(jwksFetcher auth.JWKSFetcher, skipVerify bool) *AtProtoAuthMiddleware {

     

       32
        
       	return &AtProtoAuthMiddleware{

     

       33
       -
       		jwksFetcher: jwksFetcher,

     

       34
       -
       		skipVerify:  skipVerify,

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       35
        
       	}

     

       36
        
       }

     

       37
        
       

     
···

       70
        
       			}

     

       71
        
       		} else {

     

       72
        
       			// Phase 2: Full verification with signature check

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       73
        
       			claims, err = auth.VerifyJWT(r.Context(), token, m.jwksFetcher)

     

       74
        
       			if err != nil {

     

       75
       -
       				// Try to extract issuer for better logging

     

       0
        
       
     

       76
        
       				issuer := "unknown"

     

       77
        
       				if parsedClaims, parseErr := auth.ParseJWT(token); parseErr == nil {

     

       78
        
       					issuer = parsedClaims.Issuer

     
···

       82
        
       				writeAuthError(w, "Invalid or expired token")

     

       83
        
       				return

     

       84
        
       			}

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       85
        
       		}

     

       86
        
       

     

       87
        
       		// Extract user DID from 'sub' claim

     
···

       124
        
       			claims, err = auth.ParseJWT(token)

     

       125
        
       		} else {

     

       126
        
       			// Phase 2: Full verification

     

       0
        
       
     

       127
        
       			claims, err = auth.VerifyJWT(r.Context(), token, m.jwksFetcher)

     

       128
        
       		}

     

       129
        
       

     
···

       134
        
       			return

     

       135
        
       		}

     

       136
        
       

     

       137
       -
       		// Inject user info and access token into context

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       138
        
       		ctx := context.WithValue(r.Context(), UserDIDKey, claims.Subject)

     

       139
        
       		ctx = context.WithValue(ctx, JWTClaimsKey, claims)

     

       140
        
       		ctx = context.WithValue(ctx, UserAccessToken, token)

     
···

       179
        
       	return token

     

       180
        
       }

     

       181
        
       

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       182
        
       // writeAuthError writes a JSON error response for authentication failures

     

       183
        
       func writeAuthError(w http.ResponseWriter, message string) {

     

       184
        
       	w.Header().Set("Content-Type", "application/json")

···

       3
        
       import (

     

       4
        
       	"Coves/internal/atproto/auth"

     

       5
        
       	"context"

     

       6
       +
       	"fmt"

     

       7
        
       	"log"

     

       8
        
       	"net/http"

     

       9
        
       	"strings"

     
···

       16
        
       	UserDIDKey      contextKey = "user_did"

     

       17
        
       	JWTClaimsKey    contextKey = "jwt_claims"

     

       18
        
       	UserAccessToken contextKey = "user_access_token"

     

       19
       +
       	DPoPProofKey    contextKey = "dpop_proof"

     

       20
        
       )

     

       21
        
       

     

       22
        
       // AtProtoAuthMiddleware enforces atProto OAuth authentication for protected routes

     

       23
        
       // Validates JWT Bearer tokens from the Authorization header

     

       24
       +
       // Supports DPoP (RFC 9449) for token binding verification

     

       25
        
       type AtProtoAuthMiddleware struct {

     

       26
       +
       	jwksFetcher  auth.JWKSFetcher

     

       27
       +
       	dpopVerifier *auth.DPoPVerifier

     

       28
       +
       	skipVerify   bool // For Phase 1 testing only

     

       29
        
       }

     

       30
        
       

     

       31
        
       // NewAtProtoAuthMiddleware creates a new atProto auth middleware

     

       32
        
       // skipVerify: if true, only parses JWT without signature verification (Phase 1)

     

       33
        
       //

     

       34
        
       //	if false, performs full signature verification (Phase 2)

     

       35
       +
       //

     

       36
       +
       // IMPORTANT: Call Stop() when shutting down to clean up background goroutines.

     

       37
        
       func NewAtProtoAuthMiddleware(jwksFetcher auth.JWKSFetcher, skipVerify bool) *AtProtoAuthMiddleware {

     

       38
        
       	return &AtProtoAuthMiddleware{

     

       39
       +
       		jwksFetcher:  jwksFetcher,

     

       40
       +
       		dpopVerifier: auth.NewDPoPVerifier(),

     

       41
       +
       		skipVerify:   skipVerify,

     

       42
       +
       	}

     

       43
       +
       }

     

       44
       +
       

     

       45
       +
       // Stop stops background goroutines. Call this when shutting down the server.

     

       46
       +
       // This prevents goroutine leaks from the DPoP verifier's replay protection cache.

     

       47
       +
       func (m *AtProtoAuthMiddleware) Stop() {

     

       48
       +
       	if m.dpopVerifier != nil {

     

       49
       +
       		m.dpopVerifier.Stop()

     

       50
        
       	}

     

       51
        
       }

     

       52
        
       

     
···

       85
        
       			}

     

       86
        
       		} else {

     

       87
        
       			// Phase 2: Full verification with signature check

     

       88
       +
       			//

     

       89
       +
       			// SECURITY: The access token MUST be verified before trusting any claims.

     

       90
       +
       			// DPoP is an ADDITIONAL security layer, not a replacement for signature verification.

     

       91
        
       			claims, err = auth.VerifyJWT(r.Context(), token, m.jwksFetcher)

     

       92
        
       			if err != nil {

     

       93
       +
       				// Token verification failed - REJECT

     

       94
       +
       				// DO NOT fall back to DPoP-only verification, as that would trust unverified claims

     

       95
        
       				issuer := "unknown"

     

       96
        
       				if parsedClaims, parseErr := auth.ParseJWT(token); parseErr == nil {

     

       97
        
       					issuer = parsedClaims.Issuer

     
···

       101
        
       				writeAuthError(w, "Invalid or expired token")

     

       102
        
       				return

     

       103
        
       			}

     

       104
       +
       

     

       105
       +
       			// Token signature verified - now check if DPoP binding is required

     

       106
       +
       			// If the token has a cnf.jkt claim, DPoP proof is REQUIRED

     

       107
       +
       			dpopHeader := r.Header.Get("DPoP")

     

       108
       +
       			hasCnfJkt := claims.Confirmation != nil && claims.Confirmation["jkt"] != nil

     

       109
       +
       

     

       110
       +
       			if hasCnfJkt {

     

       111
       +
       				// Token has DPoP binding - REQUIRE valid DPoP proof

     

       112
       +
       				if dpopHeader == "" {

     

       113
       +
       					log.Printf("[AUTH_FAILURE] type=missing_dpop ip=%s method=%s path=%s error=token has cnf.jkt but no DPoP header",

     

       114
       +
       						r.RemoteAddr, r.Method, r.URL.Path)

     

       115
       +
       					writeAuthError(w, "DPoP proof required")

     

       116
       +
       					return

     

       117
       +
       				}

     

       118
       +
       

     

       119
       +
       				proof, err := m.verifyDPoPBinding(r, claims, dpopHeader)

     

       120
       +
       				if err != nil {

     

       121
       +
       					log.Printf("[AUTH_FAILURE] type=dpop_verification_failed ip=%s method=%s path=%s error=%v",

     

       122
       +
       						r.RemoteAddr, r.Method, r.URL.Path, err)

     

       123
       +
       					writeAuthError(w, "Invalid DPoP proof")

     

       124
       +
       					return

     

       125
       +
       				}

     

       126
       +
       

     

       127
       +
       				// Store verified DPoP proof in context

     

       128
       +
       				ctx := context.WithValue(r.Context(), DPoPProofKey, proof)

     

       129
       +
       				r = r.WithContext(ctx)

     

       130
       +
       			} else if dpopHeader != "" {

     

       131
       +
       				// DPoP header present but token doesn't have cnf.jkt - this is suspicious

     

       132
       +
       				// Log warning but don't reject (could be a misconfigured client)

     

       133
       +
       				log.Printf("[AUTH_WARNING] type=unexpected_dpop ip=%s method=%s path=%s warning=DPoP header present but token has no cnf.jkt",

     

       134
       +
       					r.RemoteAddr, r.Method, r.URL.Path)

     

       135
       +
       			}

     

       136
        
       		}

     

       137
        
       

     

       138
        
       		// Extract user DID from 'sub' claim

     
···

       175
        
       			claims, err = auth.ParseJWT(token)

     

       176
        
       		} else {

     

       177
        
       			// Phase 2: Full verification

     

       178
       +
       			// SECURITY: Token MUST be verified before trusting claims

     

       179
        
       			claims, err = auth.VerifyJWT(r.Context(), token, m.jwksFetcher)

     

       180
        
       		}

     

       181
        
       

     
···

       186
        
       			return

     

       187
        
       		}

     

       188
        
       

     

       189
       +
       		// Check DPoP binding if token has cnf.jkt (after successful verification)

     

       190
       +
       		// SECURITY: If token has cnf.jkt but no DPoP header, we cannot trust it

     

       191
       +
       		// (could be a stolen token). Continue as unauthenticated.

     

       192
       +
       		if !m.skipVerify {

     

       193
       +
       			dpopHeader := r.Header.Get("DPoP")

     

       194
       +
       			hasCnfJkt := claims.Confirmation != nil && claims.Confirmation["jkt"] != nil

     

       195
       +
       

     

       196
       +
       			if hasCnfJkt {

     

       197
       +
       				if dpopHeader == "" {

     

       198
       +
       					// Token requires DPoP binding but no proof provided

     

       199
       +
       					// Cannot trust this token - continue without auth

     

       200
       +
       					log.Printf("[AUTH_WARNING] Optional auth: token has cnf.jkt but no DPoP header - treating as unauthenticated (potential token theft)")

     

       201
       +
       					next.ServeHTTP(w, r)

     

       202
       +
       					return

     

       203
       +
       				}

     

       204
       +
       

     

       205
       +
       				proof, err := m.verifyDPoPBinding(r, claims, dpopHeader)

     

       206
       +
       				if err != nil {

     

       207
       +
       					// DPoP verification failed - cannot trust this token

     

       208
       +
       					log.Printf("[AUTH_WARNING] Optional auth: DPoP verification failed - treating as unauthenticated: %v", err)

     

       209
       +
       					next.ServeHTTP(w, r)

     

       210
       +
       					return

     

       211
       +
       				}

     

       212
       +
       

     

       213
       +
       				// DPoP verified - inject proof into context

     

       214
       +
       				ctx := context.WithValue(r.Context(), UserDIDKey, claims.Subject)

     

       215
       +
       				ctx = context.WithValue(ctx, JWTClaimsKey, claims)

     

       216
       +
       				ctx = context.WithValue(ctx, UserAccessToken, token)

     

       217
       +
       				ctx = context.WithValue(ctx, DPoPProofKey, proof)

     

       218
       +
       				next.ServeHTTP(w, r.WithContext(ctx))

     

       219
       +
       				return

     

       220
       +
       			}

     

       221
       +
       		}

     

       222
       +
       

     

       223
       +
       		// No DPoP binding required - inject user info and access token into context

     

       224
        
       		ctx := context.WithValue(r.Context(), UserDIDKey, claims.Subject)

     

       225
        
       		ctx = context.WithValue(ctx, JWTClaimsKey, claims)

     

       226
        
       		ctx = context.WithValue(ctx, UserAccessToken, token)

     
···

       265
        
       	return token

     

       266
        
       }

     

       267
        
       

     

       268
       +
       // GetDPoPProof extracts the DPoP proof from the request context

     

       269
       +
       // Returns nil if no DPoP proof was verified

     

       270
       +
       func GetDPoPProof(r *http.Request) *auth.DPoPProof {

     

       271
       +
       	proof, _ := r.Context().Value(DPoPProofKey).(*auth.DPoPProof)

     

       272
       +
       	return proof

     

       273
       +
       }

     

       274
       +
       

     

       275
       +
       // verifyDPoPBinding verifies DPoP proof binding for an ALREADY VERIFIED token.

     

       276
       +
       //

     

       277
       +
       // SECURITY: This function ONLY verifies the DPoP proof and its binding to the token.

     

       278
       +
       // The access token MUST be signature-verified BEFORE calling this function.

     

       279
       +
       // DPoP is an ADDITIONAL security layer, not a replacement for signature verification.

     

       280
       +
       //

     

       281
       +
       // This prevents token theft attacks by proving the client possesses the private key

     

       282
       +
       // corresponding to the public key thumbprint in the token's cnf.jkt claim.

     

       283
       +
       func (m *AtProtoAuthMiddleware) verifyDPoPBinding(r *http.Request, claims *auth.Claims, dpopProofHeader string) (*auth.DPoPProof, error) {

     

       284
       +
       	// Extract the cnf.jkt claim from the already-verified token

     

       285
       +
       	jkt, err := auth.ExtractCnfJkt(claims)

     

       286
       +
       	if err != nil {

     

       287
       +
       		return nil, fmt.Errorf("token requires DPoP but missing cnf.jkt: %w", err)

     

       288
       +
       	}

     

       289
       +
       

     

       290
       +
       	// Build the HTTP URI for DPoP verification

     

       291
       +
       	// Use the full URL including scheme and host

     

       292
       +
       	scheme := strings.TrimSpace(r.URL.Scheme)

     

       293
       +
       	if forwardedProto := r.Header.Get("X-Forwarded-Proto"); forwardedProto != "" {

     

       294
       +
       		// Forwarded proto may contain a comma-separated list; use the first entry

     

       295
       +
       		parts := strings.Split(forwardedProto, ",")

     

       296
       +
       		if len(parts) > 0 && strings.TrimSpace(parts[0]) != "" {

     

       297
       +
       			scheme = strings.ToLower(strings.TrimSpace(parts[0]))

     

       298
       +
       		}

     

       299
       +
       	}

     

       300
       +
       	if scheme == "" {

     

       301
       +
       		if r.TLS != nil {

     

       302
       +
       			scheme = "https"

     

       303
       +
       		} else {

     

       304
       +
       			scheme = "http"

     

       305
       +
       		}

     

       306
       +
       	}

     

       307
       +
       	scheme = strings.ToLower(scheme)

     

       308
       +
       	httpURI := scheme + "://" + r.Host + r.URL.Path

     

       309
       +
       

     

       310
       +
       	// Verify the DPoP proof

     

       311
       +
       	proof, err := m.dpopVerifier.VerifyDPoPProof(dpopProofHeader, r.Method, httpURI)

     

       312
       +
       	if err != nil {

     

       313
       +
       		return nil, fmt.Errorf("DPoP proof verification failed: %w", err)

     

       314
       +
       	}

     

       315
       +
       

     

       316
       +
       	// Verify the binding between the proof and the token

     

       317
       +
       	if err := m.dpopVerifier.VerifyTokenBinding(proof, jkt); err != nil {

     

       318
       +
       		return nil, fmt.Errorf("DPoP binding verification failed: %w", err)

     

       319
       +
       	}

     

       320
       +
       

     

       321
       +
       	return proof, nil

     

       322
       +
       }

     

       323
       +
       

     

       324
        
       // writeAuthError writes a JSON error response for authentication failures

     

       325
        
       func writeAuthError(w http.ResponseWriter, message string) {

     

       326
        
       	w.Header().Set("Content-Type", "application/json")

+416

internal/api/middleware/auth_test.go

···

       1
        
       package middleware

     

       2
        
       

     

       3
        
       import (

     

       0
        
       
     

       4
        
       	"context"

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       5
        
       	"fmt"

     

       6
        
       	"net/http"

     

       7
        
       	"net/http/httptest"

     
···

       9
        
       	"time"

     

       10
        
       

     

       11
        
       	"github.com/golang-jwt/jwt/v5"

     

       0
        
       
     

       12
        
       )

     

       13
        
       

     

       14
        
       // mockJWKSFetcher is a test double for JWKSFetcher

     
···

       326
        
       		t.Errorf("expected nil claims, got %+v", claims)

     

       327
        
       	}

     

       328
        
       }

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

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       0
        
       
     

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       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

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       0
        
       
     

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       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

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       0
        
       
     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0

···

       1
        
       package middleware

     

       2
        
       

     

       3
        
       import (

     

       4
       +
       	"Coves/internal/atproto/auth"

     

       5
        
       	"context"

     

       6
       +
       	"crypto/ecdsa"

     

       7
       +
       	"crypto/elliptic"

     

       8
       +
       	"crypto/rand"

     

       9
       +
       	"encoding/base64"

     

       10
        
       	"fmt"

     

       11
        
       	"net/http"

     

       12
        
       	"net/http/httptest"

     
···

       14
        
       	"time"

     

       15
        
       

     

       16
        
       	"github.com/golang-jwt/jwt/v5"

     

       17
       +
       	"github.com/google/uuid"

     

       18
        
       )

     

       19
        
       

     

       20
        
       // mockJWKSFetcher is a test double for JWKSFetcher

     
···

       332
        
       		t.Errorf("expected nil claims, got %+v", claims)

     

       333
        
       	}

     

       334
        
       }

     

       335
       +
       

     

       336
       +
       // TestGetDPoPProof_NotAuthenticated tests that GetDPoPProof returns nil when no DPoP was verified

     

       337
       +
       func TestGetDPoPProof_NotAuthenticated(t *testing.T) {

     

       338
       +
       	req := httptest.NewRequest("GET", "/test", nil)

     

       339
       +
       	proof := GetDPoPProof(req)

     

       340
       +
       

     

       341
       +
       	if proof != nil {

     

       342
       +
       		t.Errorf("expected nil proof, got %+v", proof)

     

       343
       +
       	}

     

       344
       +
       }

     

       345
       +
       

     

       346
       +
       // TestRequireAuth_WithDPoP_SecurityModel tests the correct DPoP security model:

     

       347
       +
       // Token MUST be verified first, then DPoP is checked as an additional layer.

     

       348
       +
       // DPoP is NOT a fallback for failed token verification.

     

       349
       +
       func TestRequireAuth_WithDPoP_SecurityModel(t *testing.T) {

     

       350
       +
       	// Generate an ECDSA key pair for DPoP

     

       351
       +
       	privateKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

     

       352
       +
       	if err != nil {

     

       353
       +
       		t.Fatalf("failed to generate key: %v", err)

     

       354
       +
       	}

     

       355
       +
       

     

       356
       +
       	// Calculate JWK thumbprint for cnf.jkt

     

       357
       +
       	jwk := ecdsaPublicKeyToJWK(&privateKey.PublicKey)

     

       358
       +
       	thumbprint, err := auth.CalculateJWKThumbprint(jwk)

     

       359
       +
       	if err != nil {

     

       360
       +
       		t.Fatalf("failed to calculate thumbprint: %v", err)

     

       361
       +
       	}

     

       362
       +
       

     

       363
       +
       	t.Run("DPoP_is_NOT_fallback_for_failed_verification", func(t *testing.T) {

     

       364
       +
       		// SECURITY TEST: When token verification fails, DPoP should NOT be used as fallback

     

       365
       +
       		// This prevents an attacker from forging a token with their own cnf.jkt

     

       366
       +
       

     

       367
       +
       		// Create a DPoP-bound access token (unsigned - will fail verification)

     

       368
       +
       		claims := auth.Claims{

     

       369
       +
       			RegisteredClaims: jwt.RegisteredClaims{

     

       370
       +
       				Subject:   "did:plc:attacker",

     

       371
       +
       				Issuer:    "https://external.pds.local",

     

       372
       +
       				ExpiresAt: jwt.NewNumericDate(time.Now().Add(1 * time.Hour)),

     

       373
       +
       				IssuedAt:  jwt.NewNumericDate(time.Now()),

     

       374
       +
       			},

     

       375
       +
       			Scope: "atproto",

     

       376
       +
       			Confirmation: map[string]interface{}{

     

       377
       +
       				"jkt": thumbprint,

     

       378
       +
       			},

     

       379
       +
       		}

     

       380
       +
       

     

       381
       +
       		token := jwt.NewWithClaims(jwt.SigningMethodNone, claims)

     

       382
       +
       		tokenString, _ := token.SignedString(jwt.UnsafeAllowNoneSignatureType)

     

       383
       +
       

     

       384
       +
       		// Create valid DPoP proof (attacker has the private key)

     

       385
       +
       		dpopProof := createDPoPProof(t, privateKey, "GET", "https://test.local/api/endpoint")

     

       386
       +
       

     

       387
       +
       		// Mock fetcher that fails (simulating external PDS without JWKS)

     

       388
       +
       		fetcher := &mockJWKSFetcher{shouldFail: true}

     

       389
       +
       		middleware := NewAtProtoAuthMiddleware(fetcher, false) // skipVerify=false

     

       390
       +
       

     

       391
       +
       		handler := middleware.RequireAuth(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

     

       392
       +
       			t.Error("SECURITY VULNERABILITY: handler was called despite token verification failure")

     

       393
       +
       		}))

     

       394
       +
       

     

       395
       +
       		req := httptest.NewRequest("GET", "https://test.local/api/endpoint", nil)

     

       396
       +
       		req.Header.Set("Authorization", "Bearer "+tokenString)

     

       397
       +
       		req.Header.Set("DPoP", dpopProof)

     

       398
       +
       		w := httptest.NewRecorder()

     

       399
       +
       

     

       400
       +
       		handler.ServeHTTP(w, req)

     

       401
       +
       

     

       402
       +
       		// MUST reject - token verification failed, DPoP cannot substitute for signature verification

     

       403
       +
       		if w.Code != http.StatusUnauthorized {

     

       404
       +
       			t.Errorf("SECURITY: expected 401 for unverified token, got %d", w.Code)

     

       405
       +
       		}

     

       406
       +
       	})

     

       407
       +
       

     

       408
       +
       	t.Run("DPoP_required_when_cnf_jkt_present_in_verified_token", func(t *testing.T) {

     

       409
       +
       		// When token has cnf.jkt, DPoP header MUST be present

     

       410
       +
       		// This test uses skipVerify=true to simulate a verified token

     

       411
       +
       

     

       412
       +
       		claims := auth.Claims{

     

       413
       +
       			RegisteredClaims: jwt.RegisteredClaims{

     

       414
       +
       				Subject:   "did:plc:test123",

     

       415
       +
       				Issuer:    "https://test.pds.local",

     

       416
       +
       				ExpiresAt: jwt.NewNumericDate(time.Now().Add(1 * time.Hour)),

     

       417
       +
       				IssuedAt:  jwt.NewNumericDate(time.Now()),

     

       418
       +
       			},

     

       419
       +
       			Scope: "atproto",

     

       420
       +
       			Confirmation: map[string]interface{}{

     

       421
       +
       				"jkt": thumbprint,

     

       422
       +
       			},

     

       423
       +
       		}

     

       424
       +
       

     

       425
       +
       		token := jwt.NewWithClaims(jwt.SigningMethodNone, claims)

     

       426
       +
       		tokenString, _ := token.SignedString(jwt.UnsafeAllowNoneSignatureType)

     

       427
       +
       

     

       428
       +
       		// NO DPoP header - should fail when skipVerify is false

     

       429
       +
       		// Note: with skipVerify=true, DPoP is not checked

     

       430
       +
       		fetcher := &mockJWKSFetcher{}

     

       431
       +
       		middleware := NewAtProtoAuthMiddleware(fetcher, true) // skipVerify=true for parsing

     

       432
       +
       

     

       433
       +
       		handlerCalled := false

     

       434
       +
       		handler := middleware.RequireAuth(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

     

       435
       +
       			handlerCalled = true

     

       436
       +
       			w.WriteHeader(http.StatusOK)

     

       437
       +
       		}))

     

       438
       +
       

     

       439
       +
       		req := httptest.NewRequest("GET", "https://test.local/api/endpoint", nil)

     

       440
       +
       		req.Header.Set("Authorization", "Bearer "+tokenString)

     

       441
       +
       		// No DPoP header

     

       442
       +
       		w := httptest.NewRecorder()

     

       443
       +
       

     

       444
       +
       		handler.ServeHTTP(w, req)

     

       445
       +
       

     

       446
       +
       		// With skipVerify=true, DPoP is not checked, so this should succeed

     

       447
       +
       		if !handlerCalled {

     

       448
       +
       			t.Error("handler should be called when skipVerify=true")

     

       449
       +
       		}

     

       450
       +
       	})

     

       451
       +
       }

     

       452
       +
       

     

       453
       +
       // TestRequireAuth_TokenVerificationFails_DPoPNotUsedAsFallback is the key security test.

     

       454
       +
       // It ensures that DPoP cannot be used as a fallback when token signature verification fails.

     

       455
       +
       func TestRequireAuth_TokenVerificationFails_DPoPNotUsedAsFallback(t *testing.T) {

     

       456
       +
       	// Generate a key pair (attacker's key)

     

       457
       +
       	attackerKey, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

     

       458
       +
       	jwk := ecdsaPublicKeyToJWK(&attackerKey.PublicKey)

     

       459
       +
       	thumbprint, _ := auth.CalculateJWKThumbprint(jwk)

     

       460
       +
       

     

       461
       +
       	// Create a FORGED token claiming to be the victim

     

       462
       +
       	claims := auth.Claims{

     

       463
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       464
       +
       			Subject:   "did:plc:victim_user", // Attacker claims to be victim

     

       465
       +
       			Issuer:    "https://untrusted.pds",

     

       466
       +
       			ExpiresAt: jwt.NewNumericDate(time.Now().Add(1 * time.Hour)),

     

       467
       +
       			IssuedAt:  jwt.NewNumericDate(time.Now()),

     

       468
       +
       		},

     

       469
       +
       		Scope: "atproto",

     

       470
       +
       		Confirmation: map[string]interface{}{

     

       471
       +
       			"jkt": thumbprint, // Attacker uses their own key

     

       472
       +
       		},

     

       473
       +
       	}

     

       474
       +
       

     

       475
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodNone, claims)

     

       476
       +
       	tokenString, _ := token.SignedString(jwt.UnsafeAllowNoneSignatureType)

     

       477
       +
       

     

       478
       +
       	// Attacker creates a valid DPoP proof with their key

     

       479
       +
       	dpopProof := createDPoPProof(t, attackerKey, "POST", "https://api.example.com/protected")

     

       480
       +
       

     

       481
       +
       	// Fetcher fails (external PDS without JWKS)

     

       482
       +
       	fetcher := &mockJWKSFetcher{shouldFail: true}

     

       483
       +
       	middleware := NewAtProtoAuthMiddleware(fetcher, false) // skipVerify=false - REAL verification

     

       484
       +
       

     

       485
       +
       	handler := middleware.RequireAuth(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

     

       486
       +
       		t.Fatalf("CRITICAL SECURITY FAILURE: Request authenticated as %s despite forged token!",

     

       487
       +
       			GetUserDID(r))

     

       488
       +
       	}))

     

       489
       +
       

     

       490
       +
       	req := httptest.NewRequest("POST", "https://api.example.com/protected", nil)

     

       491
       +
       	req.Header.Set("Authorization", "Bearer "+tokenString)

     

       492
       +
       	req.Header.Set("DPoP", dpopProof)

     

       493
       +
       	w := httptest.NewRecorder()

     

       494
       +
       

     

       495
       +
       	handler.ServeHTTP(w, req)

     

       496
       +
       

     

       497
       +
       	// MUST reject - the token signature was never verified

     

       498
       +
       	if w.Code != http.StatusUnauthorized {

     

       499
       +
       		t.Errorf("SECURITY VULNERABILITY: Expected 401, got %d. Token was not properly verified!", w.Code)

     

       500
       +
       	}

     

       501
       +
       }

     

       502
       +
       

     

       503
       +
       // TestVerifyDPoPBinding_UsesForwardedProto ensures we honor the external HTTPS

     

       504
       +
       // scheme when TLS is terminated upstream and X-Forwarded-Proto is present.

     

       505
       +
       func TestVerifyDPoPBinding_UsesForwardedProto(t *testing.T) {

     

       506
       +
       	privateKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

     

       507
       +
       	if err != nil {

     

       508
       +
       		t.Fatalf("failed to generate key: %v", err)

     

       509
       +
       	}

     

       510
       +
       

     

       511
       +
       	jwk := ecdsaPublicKeyToJWK(&privateKey.PublicKey)

     

       512
       +
       	thumbprint, err := auth.CalculateJWKThumbprint(jwk)

     

       513
       +
       	if err != nil {

     

       514
       +
       		t.Fatalf("failed to calculate thumbprint: %v", err)

     

       515
       +
       	}

     

       516
       +
       

     

       517
       +
       	claims := &auth.Claims{

     

       518
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       519
       +
       			Subject:   "did:plc:test123",

     

       520
       +
       			Issuer:    "https://test.pds.local",

     

       521
       +
       			ExpiresAt: jwt.NewNumericDate(time.Now().Add(1 * time.Hour)),

     

       522
       +
       			IssuedAt:  jwt.NewNumericDate(time.Now()),

     

       523
       +
       		},

     

       524
       +
       		Scope: "atproto",

     

       525
       +
       		Confirmation: map[string]interface{}{

     

       526
       +
       			"jkt": thumbprint,

     

       527
       +
       		},

     

       528
       +
       	}

     

       529
       +
       

     

       530
       +
       	middleware := NewAtProtoAuthMiddleware(&mockJWKSFetcher{}, false)

     

       531
       +
       	defer middleware.Stop()

     

       532
       +
       

     

       533
       +
       	externalURI := "https://api.example.com/protected/resource"

     

       534
       +
       	dpopProof := createDPoPProof(t, privateKey, "GET", externalURI)

     

       535
       +
       

     

       536
       +
       	req := httptest.NewRequest("GET", "http://internal-service/protected/resource", nil)

     

       537
       +
       	req.Host = "api.example.com"

     

       538
       +
       	req.Header.Set("X-Forwarded-Proto", "https")

     

       539
       +
       

     

       540
       +
       	proof, err := middleware.verifyDPoPBinding(req, claims, dpopProof)

     

       541
       +
       	if err != nil {

     

       542
       +
       		t.Fatalf("expected DPoP verification to succeed with forwarded proto, got %v", err)

     

       543
       +
       	}

     

       544
       +
       

     

       545
       +
       	if proof == nil || proof.Claims == nil {

     

       546
       +
       		t.Fatal("expected DPoP proof to be returned")

     

       547
       +
       	}

     

       548
       +
       }

     

       549
       +
       

     

       550
       +
       // TestMiddlewareStop tests that the middleware can be stopped properly

     

       551
       +
       func TestMiddlewareStop(t *testing.T) {

     

       552
       +
       	fetcher := &mockJWKSFetcher{}

     

       553
       +
       	middleware := NewAtProtoAuthMiddleware(fetcher, false)

     

       554
       +
       

     

       555
       +
       	// Stop should not panic and should clean up resources

     

       556
       +
       	middleware.Stop()

     

       557
       +
       

     

       558
       +
       	// Calling Stop again should also be safe (idempotent-ish)

     

       559
       +
       	// Note: The underlying DPoPVerifier.Stop() closes a channel, so this might panic

     

       560
       +
       	// if not handled properly. We test that at least one Stop works.

     

       561
       +
       }

     

       562
       +
       

     

       563
       +
       // TestOptionalAuth_DPoPBoundToken_NoDPoPHeader tests that OptionalAuth treats

     

       564
       +
       // tokens with cnf.jkt but no DPoP header as unauthenticated (potential token theft)

     

       565
       +
       func TestOptionalAuth_DPoPBoundToken_NoDPoPHeader(t *testing.T) {

     

       566
       +
       	// Generate a key pair for DPoP binding

     

       567
       +
       	privateKey, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)

     

       568
       +
       	jwk := ecdsaPublicKeyToJWK(&privateKey.PublicKey)

     

       569
       +
       	thumbprint, _ := auth.CalculateJWKThumbprint(jwk)

     

       570
       +
       

     

       571
       +
       	// Create a DPoP-bound token (has cnf.jkt)

     

       572
       +
       	claims := auth.Claims{

     

       573
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       574
       +
       			Subject:   "did:plc:user123",

     

       575
       +
       			Issuer:    "https://test.pds.local",

     

       576
       +
       			ExpiresAt: jwt.NewNumericDate(time.Now().Add(1 * time.Hour)),

     

       577
       +
       			IssuedAt:  jwt.NewNumericDate(time.Now()),

     

       578
       +
       		},

     

       579
       +
       		Scope: "atproto",

     

       580
       +
       		Confirmation: map[string]interface{}{

     

       581
       +
       			"jkt": thumbprint,

     

       582
       +
       		},

     

       583
       +
       	}

     

       584
       +
       

     

       585
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodNone, claims)

     

       586
       +
       	tokenString, _ := token.SignedString(jwt.UnsafeAllowNoneSignatureType)

     

       587
       +
       

     

       588
       +
       	// Use skipVerify=true to simulate a verified token

     

       589
       +
       	// (In production, skipVerify would be false and VerifyJWT would be called)

     

       590
       +
       	// However, for this test we need skipVerify=false to trigger DPoP checking

     

       591
       +
       	// But the fetcher will fail, so let's use skipVerify=true and verify the logic

     

       592
       +
       	// Actually, the DPoP check only happens when skipVerify=false

     

       593
       +
       

     

       594
       +
       	t.Run("with_skipVerify_false", func(t *testing.T) {

     

       595
       +
       		// This will fail at JWT verification level, but that's expected

     

       596
       +
       		// The important thing is the code path for DPoP checking

     

       597
       +
       		fetcher := &mockJWKSFetcher{shouldFail: true}

     

       598
       +
       		middleware := NewAtProtoAuthMiddleware(fetcher, false)

     

       599
       +
       		defer middleware.Stop()

     

       600
       +
       

     

       601
       +
       		handlerCalled := false

     

       602
       +
       		var capturedDID string

     

       603
       +
       		handler := middleware.OptionalAuth(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

     

       604
       +
       			handlerCalled = true

     

       605
       +
       			capturedDID = GetUserDID(r)

     

       606
       +
       			w.WriteHeader(http.StatusOK)

     

       607
       +
       		}))

     

       608
       +
       

     

       609
       +
       		req := httptest.NewRequest("GET", "/test", nil)

     

       610
       +
       		req.Header.Set("Authorization", "Bearer "+tokenString)

     

       611
       +
       		// Deliberately NOT setting DPoP header

     

       612
       +
       		w := httptest.NewRecorder()

     

       613
       +
       

     

       614
       +
       		handler.ServeHTTP(w, req)

     

       615
       +
       

     

       616
       +
       		// Handler should be called (optional auth doesn't block)

     

       617
       +
       		if !handlerCalled {

     

       618
       +
       			t.Error("handler should be called")

     

       619
       +
       		}

     

       620
       +
       

     

       621
       +
       		// But since JWT verification fails, user should not be authenticated

     

       622
       +
       		if capturedDID != "" {

     

       623
       +
       			t.Errorf("expected empty DID when verification fails, got %s", capturedDID)

     

       624
       +
       		}

     

       625
       +
       	})

     

       626
       +
       

     

       627
       +
       	t.Run("with_skipVerify_true_dpop_not_checked", func(t *testing.T) {

     

       628
       +
       		// When skipVerify=true, DPoP is not checked (Phase 1 mode)

     

       629
       +
       		fetcher := &mockJWKSFetcher{}

     

       630
       +
       		middleware := NewAtProtoAuthMiddleware(fetcher, true)

     

       631
       +
       		defer middleware.Stop()

     

       632
       +
       

     

       633
       +
       		handlerCalled := false

     

       634
       +
       		var capturedDID string

     

       635
       +
       		handler := middleware.OptionalAuth(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

     

       636
       +
       			handlerCalled = true

     

       637
       +
       			capturedDID = GetUserDID(r)

     

       638
       +
       			w.WriteHeader(http.StatusOK)

     

       639
       +
       		}))

     

       640
       +
       

     

       641
       +
       		req := httptest.NewRequest("GET", "/test", nil)

     

       642
       +
       		req.Header.Set("Authorization", "Bearer "+tokenString)

     

       643
       +
       		// No DPoP header

     

       644
       +
       		w := httptest.NewRecorder()

     

       645
       +
       

     

       646
       +
       		handler.ServeHTTP(w, req)

     

       647
       +
       

     

       648
       +
       		if !handlerCalled {

     

       649
       +
       			t.Error("handler should be called")

     

       650
       +
       		}

     

       651
       +
       

     

       652
       +
       		// With skipVerify=true, DPoP check is bypassed - token is trusted

     

       653
       +
       		if capturedDID != "did:plc:user123" {

     

       654
       +
       			t.Errorf("expected DID when skipVerify=true, got %s", capturedDID)

     

       655
       +
       		}

     

       656
       +
       	})

     

       657
       +
       }

     

       658
       +
       

     

       659
       +
       // TestDPoPReplayProtection tests that the same DPoP proof cannot be used twice

     

       660
       +
       func TestDPoPReplayProtection(t *testing.T) {

     

       661
       +
       	// This tests the NonceCache functionality

     

       662
       +
       	cache := auth.NewNonceCache(5 * time.Minute)

     

       663
       +
       	defer cache.Stop()

     

       664
       +
       

     

       665
       +
       	jti := "unique-proof-id-123"

     

       666
       +
       

     

       667
       +
       	// First use should succeed

     

       668
       +
       	if !cache.CheckAndStore(jti) {

     

       669
       +
       		t.Error("First use of jti should succeed")

     

       670
       +
       	}

     

       671
       +
       

     

       672
       +
       	// Second use should fail (replay detected)

     

       673
       +
       	if cache.CheckAndStore(jti) {

     

       674
       +
       		t.Error("SECURITY: Replay attack not detected - same jti accepted twice")

     

       675
       +
       	}

     

       676
       +
       

     

       677
       +
       	// Different jti should succeed

     

       678
       +
       	if !cache.CheckAndStore("different-jti-456") {

     

       679
       +
       		t.Error("Different jti should succeed")

     

       680
       +
       	}

     

       681
       +
       }

     

       682
       +
       

     

       683
       +
       // Helper: createDPoPProof creates a DPoP proof JWT for testing

     

       684
       +
       func createDPoPProof(t *testing.T, privateKey *ecdsa.PrivateKey, method, uri string) string {

     

       685
       +
       	// Create JWK from public key

     

       686
       +
       	jwk := ecdsaPublicKeyToJWK(&privateKey.PublicKey)

     

       687
       +
       

     

       688
       +
       	// Create DPoP claims with UUID for jti to ensure uniqueness across tests

     

       689
       +
       	claims := auth.DPoPClaims{

     

       690
       +
       		RegisteredClaims: jwt.RegisteredClaims{

     

       691
       +
       			IssuedAt: jwt.NewNumericDate(time.Now()),

     

       692
       +
       			ID:       uuid.New().String(),

     

       693
       +
       		},

     

       694
       +
       		HTTPMethod: method,

     

       695
       +
       		HTTPURI:    uri,

     

       696
       +
       	}

     

       697
       +
       

     

       698
       +
       	// Create token with custom header

     

       699
       +
       	token := jwt.NewWithClaims(jwt.SigningMethodES256, claims)

     

       700
       +
       	token.Header["typ"] = "dpop+jwt"

     

       701
       +
       	token.Header["jwk"] = jwk

     

       702
       +
       

     

       703
       +
       	// Sign with private key

     

       704
       +
       	signedToken, err := token.SignedString(privateKey)

     

       705
       +
       	if err != nil {

     

       706
       +
       		t.Fatalf("failed to sign DPoP proof: %v", err)

     

       707
       +
       	}

     

       708
       +
       

     

       709
       +
       	return signedToken

     

       710
       +
       }

     

       711
       +
       

     

       712
       +
       // Helper: ecdsaPublicKeyToJWK converts an ECDSA public key to JWK map

     

       713
       +
       func ecdsaPublicKeyToJWK(pubKey *ecdsa.PublicKey) map[string]interface{} {

     

       714
       +
       	// Get curve name

     

       715
       +
       	var crv string

     

       716
       +
       	switch pubKey.Curve {

     

       717
       +
       	case elliptic.P256():

     

       718
       +
       		crv = "P-256"

     

       719
       +
       	case elliptic.P384():

     

       720
       +
       		crv = "P-384"

     

       721
       +
       	case elliptic.P521():

     

       722
       +
       		crv = "P-521"

     

       723
       +
       	default:

     

       724
       +
       		panic("unsupported curve")

     

       725
       +
       	}

     

       726
       +
       

     

       727
       +
       	// Encode coordinates

     

       728
       +
       	xBytes := pubKey.X.Bytes()

     

       729
       +
       	yBytes := pubKey.Y.Bytes()

     

       730
       +
       

     

       731
       +
       	// Ensure proper byte length (pad if needed)

     

       732
       +
       	keySize := (pubKey.Curve.Params().BitSize + 7) / 8

     

       733
       +
       	xPadded := make([]byte, keySize)

     

       734
       +
       	yPadded := make([]byte, keySize)

     

       735
       +
       	copy(xPadded[keySize-len(xBytes):], xBytes)

     

       736
       +
       	copy(yPadded[keySize-len(yBytes):], yBytes)

     

       737
       +
       

     

       738
       +
       	return map[string]interface{}{

     

       739
       +
       		"kty": "EC",

     

       740
       +
       		"crv": crv,

     

       741
       +
       		"x":   base64.RawURLEncoding.EncodeToString(xPadded),

     

       742
       +
       		"y":   base64.RawURLEncoding.EncodeToString(yPadded),

     

       743
       +
       	}

     

       744
       +
       }

+134 -2

internal/atproto/auth/README.md

···

       110
        
       5. Find matching key by `kid` from JWT header

     

       111
        
       6. Cache the JWKS for 1 hour

     

       112
        
       

     

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       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       113
        
       ## Security Considerations

     

       114
        
       

     

       115
        
       ### ✅ Implemented

     
···

       120
        
       - Required claims validation (sub, iss)

     

       121
        
       - Key caching with TTL

     

       122
        
       - Secure error messages (no internal details leaked)

     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       0
        
       
     

       123
        
       

     

       124
        
       ### ⚠️ Not Yet Implemented

     

       125
        
       

     

       126
       -
       - DPoP validation (for replay attack prevention)

     

       127
        
       - Scope validation (checking `scope` claim)

     

       128
        
       - Audience validation (checking `aud` claim)

     

       129
        
       - Rate limiting per DID

     
···

       186
        
       

     

       187
        
       ## Future Enhancements

     

       188
        
       

     

       189
       -
       - [ ] DPoP proof validation

     

       190
        
       - [ ] Scope-based authorization

     

       191
        
       - [ ] Audience claim validation

     

       192
        
       - [ ] Token revocation support

···

       110
        
       5. Find matching key by `kid` from JWT header

     

       111
        
       6. Cache the JWKS for 1 hour

     

       112
        
       

     

       113
       +
       ## DPoP Token Binding

     

       114
       +
       

     

       115
       +
       DPoP (Demonstrating Proof-of-Possession) binds access tokens to client-controlled cryptographic keys, preventing token theft and replay attacks.

     

       116
       +
       

     

       117
       +
       ### What is DPoP?

     

       118
       +
       

     

       119
       +
       DPoP is an OAuth extension (RFC 9449) that adds proof-of-possession semantics to bearer tokens. When a PDS issues a DPoP-bound access token:

     

       120
       +
       

     

       121
       +
       1. Access token contains `cnf.jkt` claim (JWK thumbprint of client's public key)

     

       122
       +
       2. Client creates a DPoP proof JWT signed with their private key

     

       123
       +
       3. Server verifies the proof signature and checks it matches the token's `cnf.jkt`

     

       124
       +
       

     

       125
       +
       ### CRITICAL: DPoP Security Model

     

       126
       +
       

     

       127
       +
       > ⚠️ **DPoP is an ADDITIONAL security layer, NOT a replacement for token signature verification.**

     

       128
       +
       

     

       129
       +
       The correct verification order is:

     

       130
       +
       1. **ALWAYS verify the access token signature first** (via JWKS, HS256 shared secret, or DID resolution)

     

       131
       +
       2. **If the verified token has `cnf.jkt`, REQUIRE valid DPoP proof**

     

       132
       +
       3. **NEVER use DPoP as a fallback when signature verification fails**

     

       133
       +
       

     

       134
       +
       **Why This Matters**: An attacker could create a fake token with `sub: "did:plc:victim"` and their own `cnf.jkt`, then present a valid DPoP proof signed with their key. If we accept DPoP as a fallback, the attacker can impersonate any user.

     

       135
       +
       

     

       136
       +
       ### How DPoP Works

     

       137
       +
       

     

       138
       +
       ```

     

       139
       +
       ┌─────────────┐                          ┌─────────────┐

     

       140
       +
       │   Client    │                          │   Server    │

     

       141
       +
       │             │                          │  (Coves)    │

     

       142
       +
       └─────────────┘                          └─────────────┘

     

       143
       +
              │                                        │

     

       144
       +
              │ 1. Authorization: Bearer <token>       │

     

       145
       +
              │    DPoP: <proof-jwt>                  │

     

       146
       +
              │───────────────────────────────────────>│

     

       147
       +
              │                                        │

     

       148
       +
              │                                        │ 2. VERIFY token signature

     

       149
       +
              │                                        │    (REQUIRED - no fallback!)

     

       150
       +
              │                                        │

     

       151
       +
              │                                        │ 3. If token has cnf.jkt:

     

       152
       +
              │                                        │    - Verify DPoP proof

     

       153
       +
              │                                        │    - Check thumbprint match

     

       154
       +
              │                                        │

     

       155
       +
              │                              200 OK    │

     

       156
       +
              │<───────────────────────────────────────│

     

       157
       +
       ```

     

       158
       +
       

     

       159
       +
       ### When DPoP is Required

     

       160
       +
       

     

       161
       +
       DPoP verification is **REQUIRED** when:

     

       162
       +
       - Access token signature has been verified AND

     

       163
       +
       - Access token contains `cnf.jkt` claim (DPoP-bound)

     

       164
       +
       

     

       165
       +
       If the token has `cnf.jkt` but no DPoP header is present, the request is **REJECTED**.

     

       166
       +
       

     

       167
       +
       ### Replay Protection

     

       168
       +
       

     

       169
       +
       DPoP proofs include a unique `jti` (JWT ID) claim. The server tracks seen `jti` values to prevent replay attacks:

     

       170
       +
       

     

       171
       +
       ```go

     

       172
       +
       // Create a verifier with replay protection (default)

     

       173
       +
       verifier := auth.NewDPoPVerifier()

     

       174
       +
       defer verifier.Stop() // Stop cleanup goroutine on shutdown

     

       175
       +
       

     

       176
       +
       // The verifier automatically rejects reused jti values within the proof validity window (5 minutes)

     

       177
       +
       ```

     

       178
       +
       

     

       179
       +
       ### DPoP Implementation

     

       180
       +
       

     

       181
       +
       The `dpop.go` module provides:

     

       182
       +
       

     

       183
       +
       ```go

     

       184
       +
       // Create a verifier with replay protection

     

       185
       +
       verifier := auth.NewDPoPVerifier()

     

       186
       +
       defer verifier.Stop()

     

       187
       +
       

     

       188
       +
       // Verify the DPoP proof

     

       189
       +
       proof, err := verifier.VerifyDPoPProof(dpopHeader, "POST", "https://coves.social/xrpc/...")

     

       190
       +
       if err != nil {

     

       191
       +
           // Invalid proof (includes replay detection)

     

       192
       +
       }

     

       193
       +
       

     

       194
       +
       // Verify it binds to the VERIFIED access token

     

       195
       +
       expectedThumbprint, err := auth.ExtractCnfJkt(claims)

     

       196
       +
       if err != nil {

     

       197
       +
           // Token not DPoP-bound

     

       198
       +
       }

     

       199
       +
       

     

       200
       +
       if err := verifier.VerifyTokenBinding(proof, expectedThumbprint); err != nil {

     

       201
       +
           // Proof doesn't match token

     

       202
       +
       }

     

       203
       +
       ```

     

       204
       +
       

     

       205
       +
       ### DPoP Proof Format

     

       206
       +
       

     

       207
       +
       The DPoP header contains a JWT with:

     

       208
       +
       

     

       209
       +
       **Header**:

     

       210
       +
       - `typ`: `"dpop+jwt"` (required)

     

       211
       +
       - `alg`: `"ES256"` (or other supported algorithm)

     

       212
       +
       - `jwk`: Client's public key (JWK format)

     

       213
       +
       

     

       214
       +
       **Claims**:

     

       215
       +
       - `jti`: Unique proof identifier (tracked for replay protection)

     

       216
       +
       - `htm`: HTTP method (e.g., `"POST"`)

     

       217
       +
       - `htu`: HTTP URI (without query/fragment)

     

       218
       +
       - `iat`: Timestamp (must be recent, within 5 minutes)

     

       219
       +
       

     

       220
       +
       **Example**:

     

       221
       +
       ```json

     

       222
       +
       {

     

       223
       +
         "typ": "dpop+jwt",

     

       224
       +
         "alg": "ES256",

     

       225
       +
         "jwk": {

     

       226
       +
           "kty": "EC",

     

       227
       +
           "crv": "P-256",

     

       228
       +
           "x": "...",

     

       229
       +
           "y": "..."

     

       230
       +
         }

     

       231
       +
       }

     

       232
       +
       {

     

       233
       +
         "jti": "unique-id-123",

     

       234
       +
         "htm": "POST",

     

       235
       +
         "htu": "https://coves.social/xrpc/social.coves.community.create",

     

       236
       +
         "iat": 1700000000

     

       237
       +
       }

     

       238
       +
       ```

     

       239
       +
       

     

       240
        
       ## Security Considerations

     

       241
        
       

     

       242
        
       ### ✅ Implemented

     
···

       247
        
       - Required claims validation (sub, iss)

     

       248
        
       - Key caching with TTL

     

       249
        
       - Secure error messages (no internal details leaked)

     

       250
       +
       - **DPoP proof verification** (proof-of-possession for token binding)

     

       251
       +
       - **DPoP thumbprint validation** (prevents token theft attacks)

     

       252
       +
       - **DPoP freshness checks** (5-minute proof validity window)

     

       253
       +
       - **DPoP replay protection** (jti tracking with in-memory cache)

     

       254
       +
       - **Secure DPoP model** (DPoP required AFTER signature verification, never as fallback)

     

       255
        
       

     

       256
        
       ### ⚠️ Not Yet Implemented

     

       257
        
       

     

       258
       +
       - Server-issued DPoP nonces (additional replay protection)

     

       259
        
       - Scope validation (checking `scope` claim)

     

       260
        
       - Audience validation (checking `aud` claim)

     

       261
        
       - Rate limiting per DID

     
···

       318
        
       

     

       319
        
       ## Future Enhancements

     

       320
        
       

     

       321
       +
       - [ ] DPoP nonce validation (server-managed nonce for additional replay protection)

     

       322
        
       - [ ] Scope-based authorization

     

       323
        
       - [ ] Audience claim validation

     

       324
        
       - [ ] Token revocation support

+4 -1

.gitignore

···

       47
        
       

     

       48
        
       # Build artifacts

     

       49
        
       /validate-lexicon

     

       50
       -
       /bin/
     

       0
        
       
     

       0
        
       
     

       0

···

       47
        
       

     

       48
        
       # Build artifacts

     

       49
        
       /validate-lexicon

     

       50
       +
       /bin/

     

       51
       +
       

     

       52
       +
       # Go build cache

     

       53
       +
       .cache/

+5 -6

go.mod

···

       1
        
       module Coves

     

       2
        
       

     

       3
       -
       go 1.24.0

     

       4
        
       

     

       5
        
       require (

     

       6
       -
       	github.com/bluesky-social/indigo v0.0.0-20251009212240-20524de167fe

     

       7
        
       	github.com/go-chi/chi/v5 v5.2.1

     

       8
        
       	github.com/golang-jwt/jwt/v5 v5.3.0

     

       9
        
       	github.com/gorilla/websocket v1.5.3

     
···

       11
        
       	github.com/lestrrat-go/jwx/v2 v2.0.12

     

       12
        
       	github.com/lib/pq v1.10.9

     

       13
        
       	github.com/pressly/goose/v3 v3.22.1

     

       14
       -
       	github.com/stretchr/testify v1.9.0

     

       0
        
       
     

       15
        
       	golang.org/x/net v0.46.0

     

       16
        
       	golang.org/x/time v0.3.0

     

       17
        
       )

     

       18
        
       

     

       19
        
       require (

     

       20
        
       	github.com/beorn7/perks v1.0.1 // indirect

     

       21
       -
       	github.com/carlmjohnson/versioninfo v0.22.5 // indirect

     

       22
        
       	github.com/cespare/xxhash/v2 v2.2.0 // indirect

     

       23
        
       	github.com/davecgh/go-spew v1.1.1 // indirect

     

       24
        
       	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0 // indirect

     

       0
        
       
     

       25
        
       	github.com/felixge/httpsnoop v1.0.4 // indirect

     

       26
        
       	github.com/go-logr/logr v1.4.1 // indirect

     

       27
        
       	github.com/go-logr/stdr v1.2.2 // indirect

     
···

       71
        
       	github.com/segmentio/asm v1.2.0 // indirect

     

       72
        
       	github.com/sethvargo/go-retry v0.3.0 // indirect

     

       73
        
       	github.com/spaolacci/murmur3 v1.1.0 // indirect

     

       74
       -
       	github.com/stretchr/objx v0.5.2 // indirect

     

       75
        
       	github.com/whyrusleeping/cbor-gen v0.2.1-0.20241030202151-b7a6831be65e // indirect

     

       76
        
       	github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f // indirect

     

       77
        
       	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect

     

       78
       -
       	github.com/xeipuuv/gojsonschema v1.2.0 // indirect

     

       79
        
       	gitlab.com/yawning/secp256k1-voi v0.0.0-20230925100816-f2616030848b // indirect

     

       80
        
       	gitlab.com/yawning/tuplehash v0.0.0-20230713102510-df83abbf9a02 // indirect

     

       81
        
       	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.46.1 // indirect

···

       1
        
       module Coves

     

       2
        
       

     

       3
       +
       go 1.25

     

       4
        
       

     

       5
        
       require (

     

       6
       +
       	github.com/bluesky-social/indigo v0.0.0-20251127021457-6f2658724b36

     

       7
        
       	github.com/go-chi/chi/v5 v5.2.1

     

       8
        
       	github.com/golang-jwt/jwt/v5 v5.3.0

     

       9
        
       	github.com/gorilla/websocket v1.5.3

     
···

       11
        
       	github.com/lestrrat-go/jwx/v2 v2.0.12

     

       12
        
       	github.com/lib/pq v1.10.9

     

       13
        
       	github.com/pressly/goose/v3 v3.22.1

     

       14
       +
       	github.com/stretchr/testify v1.10.0

     

       15
       +
       	github.com/xeipuuv/gojsonschema v1.2.0

     

       16
        
       	golang.org/x/net v0.46.0

     

       17
        
       	golang.org/x/time v0.3.0

     

       18
        
       )

     

       19
        
       

     

       20
        
       require (

     

       21
        
       	github.com/beorn7/perks v1.0.1 // indirect

     

       0
        
       
     

       22
        
       	github.com/cespare/xxhash/v2 v2.2.0 // indirect

     

       23
        
       	github.com/davecgh/go-spew v1.1.1 // indirect

     

       24
        
       	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0 // indirect

     

       25
       +
       	github.com/earthboundkid/versioninfo/v2 v2.24.1 // indirect

     

       26
        
       	github.com/felixge/httpsnoop v1.0.4 // indirect

     

       27
        
       	github.com/go-logr/logr v1.4.1 // indirect

     

       28
        
       	github.com/go-logr/stdr v1.2.2 // indirect

     
···

       72
        
       	github.com/segmentio/asm v1.2.0 // indirect

     

       73
        
       	github.com/sethvargo/go-retry v0.3.0 // indirect

     

       74
        
       	github.com/spaolacci/murmur3 v1.1.0 // indirect

     

       0
        
       
     

       75
        
       	github.com/whyrusleeping/cbor-gen v0.2.1-0.20241030202151-b7a6831be65e // indirect

     

       76
        
       	github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f // indirect

     

       77
        
       	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect

     

       0
        
       
     

       78
        
       	gitlab.com/yawning/secp256k1-voi v0.0.0-20230925100816-f2616030848b // indirect

     

       79
        
       	gitlab.com/yawning/tuplehash v0.0.0-20230713102510-df83abbf9a02 // indirect

     

       80
        
       	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.46.1 // indirect

+6 -8

go.sum

···

       2
        
       github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=

     

       3
        
       github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=

     

       4
        
       github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=

     

       5
       -
       github.com/bluesky-social/indigo v0.0.0-20251009212240-20524de167fe h1:VBhaqE5ewQgXbY5SfSWFZC/AwHFo7cHxZKFYi2ce9Yo=

     

       6
       -
       github.com/bluesky-social/indigo v0.0.0-20251009212240-20524de167fe/go.mod h1:RuQVrCGm42QNsgumKaR6se+XkFKfCPNwdCiTvqKRUck=

     

       7
       -
       github.com/carlmjohnson/versioninfo v0.22.5 h1:O00sjOLUAFxYQjlN/bzYTuZiS0y6fWDQjMRvwtKgwwc=

     

       8
       -
       github.com/carlmjohnson/versioninfo v0.22.5/go.mod h1:QT9mph3wcVfISUKd0i9sZfVrPviHuSF+cUtLjm2WSf8=

     

       9
        
       github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=

     

       10
        
       github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=

     

       11
        
       github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=

     
···

       17
        
       github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0/go.mod h1:v57UDF4pDQJcEfFUCRop3lJL149eHGSe9Jvczhzjo/0=

     

       18
        
       github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=

     

       19
        
       github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=

     

       0
        
       
     

       0
        
       
     

       20
        
       github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=

     

       21
        
       github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=

     

       22
        
       github.com/go-chi/chi/v5 v5.2.1 h1:KOIHODQj58PmL80G2Eak4WdvUzjSJSm0vG72crDCqb8=

     
···

       172
        
       github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=

     

       173
        
       github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=

     

       174
        
       github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=

     

       175
       -
       github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=

     

       176
       -
       github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=

     

       177
        
       github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

     

       178
        
       github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=

     

       179
        
       github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=

     
···

       182
        
       github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=

     

       183
        
       github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=

     

       184
        
       github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=

     

       185
       -
       github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=

     

       186
       -
       github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=

     

       187
        
       github.com/urfave/cli v1.22.10/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=

     

       188
        
       github.com/warpfork/go-wish v0.0.0-20220906213052-39a1cc7a02d0 h1:GDDkbFiaK8jsSDJfjId/PEGEShv6ugrt4kYsC5UIDaQ=

     

       189
        
       github.com/warpfork/go-wish v0.0.0-20220906213052-39a1cc7a02d0/go.mod h1:x6AKhvSSexNrVSrViXSHUEbICjmGXhtgABaHIySUSGw=

···

       2
        
       github.com/benbjohnson/clock v1.1.0/go.mod h1:J11/hYXuz8f4ySSvYwY0FKfm+ezbsZBKZxNJlLklBHA=

     

       3
        
       github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=

     

       4
        
       github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=

     

       5
       +
       github.com/bluesky-social/indigo v0.0.0-20251127021457-6f2658724b36 h1:Vc+l4sltxQfBT8qC3dm87PRYInmxlGyF1dmpjaW0WkU=

     

       6
       +
       github.com/bluesky-social/indigo v0.0.0-20251127021457-6f2658724b36/go.mod h1:Pm2I1+iDXn/hLbF7XCg/DsZi6uDCiOo7hZGWprSM7k0=

     

       0
        
       
     

       0
        
       
     

       7
        
       github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=

     

       8
        
       github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=

     

       9
        
       github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=

     
···

       15
        
       github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0/go.mod h1:v57UDF4pDQJcEfFUCRop3lJL149eHGSe9Jvczhzjo/0=

     

       16
        
       github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=

     

       17
        
       github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=

     

       18
       +
       github.com/earthboundkid/versioninfo/v2 v2.24.1 h1:SJTMHaoUx3GzjjnUO1QzP3ZXK6Ee/nbWyCm58eY3oUg=

     

       19
       +
       github.com/earthboundkid/versioninfo/v2 v2.24.1/go.mod h1:VcWEooDEuyUJnMfbdTh0uFN4cfEIg+kHMuWB2CDCLjw=

     

       20
        
       github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=

     

       21
        
       github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=

     

       22
        
       github.com/go-chi/chi/v5 v5.2.1 h1:KOIHODQj58PmL80G2Eak4WdvUzjSJSm0vG72crDCqb8=

     
···

       172
        
       github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=

     

       173
        
       github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=

     

       174
        
       github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=

     

       0
        
       
     

       0
        
       
     

       175
        
       github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

     

       176
        
       github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=

     

       177
        
       github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=

     
···

       180
        
       github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=

     

       181
        
       github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=

     

       182
        
       github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=

     

       183
       +
       github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=

     

       184
       +
       github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=

     

       185
        
       github.com/urfave/cli v1.22.10/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=

     

       186
        
       github.com/warpfork/go-wish v0.0.0-20220906213052-39a1cc7a02d0 h1:GDDkbFiaK8jsSDJfjId/PEGEShv6ugrt4kYsC5UIDaQ=

     

       187
        
       github.com/warpfork/go-wish v0.0.0-20220906213052-39a1cc7a02d0/go.mod h1:x6AKhvSSexNrVSrViXSHUEbICjmGXhtgABaHIySUSGw=

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