commit 275d63d30f9849af687c859e3ed2f9ebba6cb5b3 · veryroundbird.house/core

-15

cmd/keyfetch/format.go

···

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       package main

     

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       import (

     

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       	"fmt"

     

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       )

     

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       func formatKeyData(repoguardPath, gitDir, logPath, endpoint string, data []map[string]interface{}) string {

     

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       	var result string

     

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       	for _, entry := range data {

     

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       		result += fmt.Sprintf(

     

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       			`command="%s -base-dir %s -user %s -log-path %s -internal-api %s",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty %s`+"\n",

     

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       			repoguardPath, gitDir, entry["did"], logPath, endpoint, entry["key"])

     

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       	}

     

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       	return result

     

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       }

-46

cmd/keyfetch/main.go

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       // This program must be configured to run as the sshd AuthorizedKeysCommand.

     

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       // The format looks something like this:

     

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       //   Match User git

     

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       //     AuthorizedKeysCommand /keyfetch -internal-api http://localhost:5444 -repoguard-path /home/git/repoguard

     

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       //     AuthorizedKeysCommandUser nobody

     

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       //

     

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       // The command and its parent directories must be owned by root and set to 0755. Hence, the ideal location for this is

     

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       // somewhere already owned by root so you don't have to mess with directory perms.

     

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       package main

     

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       import (

     

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       	"encoding/json"

     

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       	"flag"

     

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       	"fmt"

     

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       	"io"

     

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       	"log"

     

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       	"net/http"

     

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       )

     

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       func main() {

     

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       	endpoint := flag.String("internal-api", "http://localhost:5444", "Internal API endpoint")

     

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       	repoguardPath := flag.String("repoguard-path", "/home/git/repoguard", "Path to the repoguard binary")

     

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       	gitDir := flag.String("git-dir", "/home/git", "Path to the git directory")

     

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       	logPath := flag.String("log-path", "/home/git/log", "Path to log file")

     

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       	flag.Parse()

     

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       	resp, err := http.Get(*endpoint + "/keys")

     

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       	if err != nil {

     

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       		log.Fatalf("error fetching keys: %v", err)

     

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       	}

     

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       	defer resp.Body.Close()

     

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       	body, err := io.ReadAll(resp.Body)

     

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       	if err != nil {

     

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       		log.Fatalf("error reading response body: %v", err)

     

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       	}

     

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       	var data []map[string]interface{}

     

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       	err = json.Unmarshal(body, &data)

     

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       	if err != nil {

     

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       		log.Fatalf("error unmarshalling response body: %v", err)

     

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       	}

     

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       	fmt.Print(formatKeyData(*repoguardPath, *gitDir, *logPath, *endpoint, data))

     

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       -
       }

+33

cmd/knot/main.go

···

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       package main

     

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       +
       

     

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       import (

     

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       	"context"

     

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       	"os"

     

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       +
       

     

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       	"github.com/urfave/cli/v3"

     

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       	"tangled.sh/tangled.sh/core/guard"

     

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       	"tangled.sh/tangled.sh/core/keyfetch"

     

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       	"tangled.sh/tangled.sh/core/knotserver"

     

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       	"tangled.sh/tangled.sh/core/log"

     

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       )

     

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       func main() {

     

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       	cmd := &cli.Command{

     

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       		Name:  "knot",

     

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       		Usage: "knot administration and operation tool",

     

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       		Commands: []*cli.Command{

     

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       			guard.Command(),

     

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       			knotserver.Command(),

     

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       			keyfetch.Command(),

     

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       		},

     

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       	}

     

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       +
       

     

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       	ctx := context.Background()

     

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       	logger := log.New("knot")

     

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       	ctx = log.IntoContext(ctx, logger.With("command", cmd.Name))

     

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       +
       

     

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       	if err := cmd.Run(ctx, os.Args); err != nil {

     

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       		logger.Error(err.Error())

     

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       		os.Exit(-1)

     

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       	}

     

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       }

-207

cmd/repoguard/main.go

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       package main

     

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       import (

     

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       	"context"

     

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       	"flag"

     

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       	"fmt"

     

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       	"log"

     

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       	"net/http"

     

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       	"net/url"

     

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       	"os"

     

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       	"os/exec"

     

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       	"strings"

     

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       	"time"

     

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       	securejoin "github.com/cyphar/filepath-securejoin"

     

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       	"tangled.sh/tangled.sh/core/appview/idresolver"

     

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       )

     

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       var (

     

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       	logger   *log.Logger

     

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       	logFile  *os.File

     

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       	clientIP string

     

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       	// Command line flags

     

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       	incomingUser = flag.String("user", "", "Allowed git user")

     

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       	baseDirFlag  = flag.String("base-dir", "/home/git", "Base directory for git repositories")

     

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       	logPathFlag  = flag.String("log-path", "/var/log/git-wrapper.log", "Path to log file")

     

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       	endpoint     = flag.String("internal-api", "http://localhost:5444", "Internal API endpoint")

     

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       )

     

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       func main() {

     

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       	flag.Parse()

     

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       	defer cleanup()

     

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       	initLogger()

     

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       	// Get client IP from SSH environment

     

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       	if connInfo := os.Getenv("SSH_CONNECTION"); connInfo != "" {

     

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       		parts := strings.Fields(connInfo)

     

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       		if len(parts) > 0 {

     

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       			clientIP = parts[0]

     

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       		}

     

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       	}

     

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       	if *incomingUser == "" {

     

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       		exitWithLog("access denied: no user specified")

     

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       	}

     

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       	sshCommand := os.Getenv("SSH_ORIGINAL_COMMAND")

     

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       	logEvent("Connection attempt", map[string]interface{}{

     

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       		"user":    *incomingUser,

     

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       		"command": sshCommand,

     

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       		"client":  clientIP,

     

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       	})

     

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       	if sshCommand == "" {

     

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       		exitWithLog("access denied: we don't serve interactive shells :)")

     

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       	}

     

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       	cmdParts := strings.Fields(sshCommand)

     

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       	if len(cmdParts) < 2 {

     

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       		exitWithLog("invalid command format")

     

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       	}

     

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       	gitCommand := cmdParts[0]

     

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       	// did:foo/repo-name or

     

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       	// handle/repo-name or

     

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       	// any of the above with a leading slash (/)

     

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       	components := strings.Split(strings.TrimPrefix(strings.Trim(cmdParts[1], "'"), "/"), "/")

     

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       	logEvent("Command components", map[string]interface{}{

     

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       		"components": components,

     

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       -
       	})

     

       76
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       	if len(components) != 2 {

     

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       		exitWithLog("invalid repo format, needs <user>/<repo> or /<user>/<repo>")

     

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       	}

     

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       	didOrHandle := components[0]

     

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       	did := resolveToDid(didOrHandle)

     

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       	repoName := components[1]

     

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       	qualifiedRepoName, _ := securejoin.SecureJoin(did, repoName)

     

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       	validCommands := map[string]bool{

     

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       		"git-receive-pack":   true,

     

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       		"git-upload-pack":    true,

     

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       		"git-upload-archive": true,

     

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       	}

     

       90
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       	if !validCommands[gitCommand] {

     

       91
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       		exitWithLog("access denied: invalid git command")

     

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       	}

     

       93
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       -
       

     

       94
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       	if gitCommand != "git-upload-pack" {

     

       95
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       		if !isPushPermitted(*incomingUser, qualifiedRepoName) {

     

       96
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       			logEvent("all infos", map[string]interface{}{

     

       97
       97
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       				"did":      *incomingUser,

     

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       				"reponame": qualifiedRepoName,

     

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       			})

     

       100
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       			exitWithLog("access denied: user not allowed")

     

       101
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       		}

     

       102
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       	}

     

       103
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       -
       

     

       104
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       	fullPath, _ := securejoin.SecureJoin(*baseDirFlag, qualifiedRepoName)

     

       105
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       106
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       	logEvent("Processing command", map[string]interface{}{

     

       107
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       		"user":     *incomingUser,

     

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       		"command":  gitCommand,

     

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       		"repo":     repoName,

     

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       		"fullPath": fullPath,

     

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       		"client":   clientIP,

     

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       	})

     

       113
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       -
       

     

       114
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       -
       	if gitCommand == "git-upload-pack" {

     

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       		fmt.Fprintf(os.Stderr, "\x02%s\n", "Welcome to this knot!")

     

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       	} else {

     

       117
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       		fmt.Fprintf(os.Stderr, "%s\n", "Welcome to this knot!")

     

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       	}

     

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       120
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       	cmd := exec.Command(gitCommand, fullPath)

     

       121
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       	cmd.Stdout = os.Stdout

     

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       	cmd.Stderr = os.Stderr

     

       123
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       	cmd.Stdin = os.Stdin

     

       124
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       125
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       	if err := cmd.Run(); err != nil {

     

       126
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       		exitWithLog(fmt.Sprintf("command failed: %v", err))

     

       127
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       	}

     

       128
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       129
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       	logEvent("Command completed", map[string]interface{}{

     

       130
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       		"user":    *incomingUser,

     

       131
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       		"command": gitCommand,

     

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       		"repo":    repoName,

     

       133
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       -
       		"success": true,

     

       134
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       -
       	})

     

       135
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       }

     

       136
       136
       -
       

     

       137
       137
       -
       func resolveToDid(didOrHandle string) string {

     

       138
       138
       -
       	resolver := idresolver.DefaultResolver()

     

       139
       139
       -
       	ident, err := resolver.ResolveIdent(context.Background(), didOrHandle)

     

       140
       140
       -
       	if err != nil {

     

       141
       141
       -
       		exitWithLog(fmt.Sprintf("error resolving handle: %v", err))

     

       142
       142
       -
       	}

     

       143
       143
       -
       

     

       144
       144
       -
       	// did:plc:foobarbaz/repo

     

       145
       145
       -
       	return ident.DID.String()

     

       146
       146
       -
       }

     

       147
       147
       -
       

     

       148
       148
       -
       func initLogger() {

     

       149
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       -
       	var err error

     

       150
       150
       -
       	logFile, err = os.OpenFile(*logPathFlag, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600)

     

       151
       151
       -
       	if err != nil {

     

       152
       152
       -
       		fmt.Fprintf(os.Stderr, "failed to open log file: %v\n", err)

     

       153
       153
       -
       		os.Exit(1)

     

       154
       154
       -
       	}

     

       155
       155
       -
       

     

       156
       156
       -
       	logger = log.New(logFile, "", 0)

     

       157
       157
       -
       }

     

       158
       158
       -
       

     

       159
       159
       -
       func logEvent(event string, fields map[string]interface{}) {

     

       160
       160
       -
       	entry := fmt.Sprintf(

     

       161
       161
       -
       		"timestamp=%q event=%q",

     

       162
       162
       -
       		time.Now().Format(time.RFC3339),

     

       163
       163
       -
       		event,

     

       164
       164
       -
       	)

     

       165
       165
       -
       

     

       166
       166
       -
       	for k, v := range fields {

     

       167
       167
       -
       		entry += fmt.Sprintf(" %s=%q", k, v)

     

       168
       168
       -
       	}

     

       169
       169
       -
       

     

       170
       170
       -
       	logger.Println(entry)

     

       171
       171
       -
       }

     

       172
       172
       -
       

     

       173
       173
       -
       func exitWithLog(message string) {

     

       174
       174
       -
       	logEvent("Access denied", map[string]interface{}{

     

       175
       175
       -
       		"error": message,

     

       176
       176
       -
       	})

     

       177
       177
       -
       	logFile.Sync()

     

       178
       178
       -
       	fmt.Fprintf(os.Stderr, "error: %s\n", message)

     

       179
       179
       -
       	os.Exit(1)

     

       180
       180
       -
       }

     

       181
       181
       -
       

     

       182
       182
       -
       func cleanup() {

     

       183
       183
       -
       	if logFile != nil {

     

       184
       184
       -
       		logFile.Sync()

     

       185
       185
       -
       		logFile.Close()

     

       186
       186
       -
       	}

     

       187
       187
       -
       }

     

       188
       188
       -
       

     

       189
       189
       -
       func isPushPermitted(user, qualifiedRepoName string) bool {

     

       190
       190
       -
       	u, _ := url.Parse(*endpoint + "/push-allowed")

     

       191
       191
       -
       	q := u.Query()

     

       192
       192
       -
       	q.Add("user", user)

     

       193
       193
       -
       	q.Add("repo", qualifiedRepoName)

     

       194
       194
       -
       	u.RawQuery = q.Encode()

     

       195
       195
       -
       

     

       196
       196
       -
       	req, err := http.Get(u.String())

     

       197
       197
       -
       	if err != nil {

     

       198
       198
       -
       		exitWithLog(fmt.Sprintf("error verifying permissions: %v", err))

     

       199
       199
       -
       	}

     

       200
       200
       -
       

     

       201
       201
       -
       	logEvent("url", map[string]interface{}{

     

       202
       202
       -
       		"url":    u.String(),

     

       203
       203
       -
       		"status": req.Status,

     

       204
       204
       -
       	})

     

       205
       205
       -
       

     

       206
       206
       -
       	return req.StatusCode == http.StatusNoContent

     

       207
       207
       -
       }

go.mod

···

       28
       28
        
       	github.com/posthog/posthog-go v1.5.5

     

       29
       29
        
       	github.com/resend/resend-go/v2 v2.15.0

     

       30
       30
        
       	github.com/sethvargo/go-envconfig v1.1.0

     

       31
       31
       +
       	github.com/urfave/cli/v3 v3.3.3

     

       31
       32
        
       	github.com/whyrusleeping/cbor-gen v0.3.1

     

       32
       33
        
       	github.com/yuin/goldmark v1.4.13

     

       33
       34
        
       	golang.org/x/net v0.39.0

go.sum

···

       348
       348
        
       github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=

     

       349
       349
        
       github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=

     

       350
       350
        
       github.com/urfave/cli v1.22.10/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=

     

       351
       351
       +
       github.com/urfave/cli/v3 v3.3.3 h1:byCBaVdIXuLPIDm5CYZRVG6NvT7tv1ECqdU4YzlEa3I=

     

       352
       352
       +
       github.com/urfave/cli/v3 v3.3.3/go.mod h1:FJSKtM/9AiiTOJL4fJ6TbMUkxBXn7GO9guZqoZtpYpo=

     

       351
       353
        
       github.com/vmihailenco/go-tinylfu v0.2.2 h1:H1eiG6HM36iniK6+21n9LLpzx1G9R3DJa2UjUjbynsI=

     

       352
       354
        
       github.com/vmihailenco/go-tinylfu v0.2.2/go.mod h1:CutYi2Q9puTxfcolkliPq4npPuofg9N9t8JVrjzwa3Q=

     

       353
       355
        
       github.com/vmihailenco/msgpack/v5 v5.3.4/go.mod h1:7xyJ9e+0+9SaZT0Wt1RGleJXzli6Q/V5KbhBonMG9jc=

+208

guard/guard.go

···

       1
       1
       +
       package guard

     

       2
       2
       +
       

     

       3
       3
       +
       import (

     

       4
       4
       +
       	"context"

     

       5
       5
       +
       	"fmt"

     

       6
       6
       +
       	"log/slog"

     

       7
       7
       +
       	"net/http"

     

       8
       8
       +
       	"net/url"

     

       9
       9
       +
       	"os"

     

       10
       10
       +
       	"os/exec"

     

       11
       11
       +
       	"strings"

     

       12
       12
       +
       

     

       13
       13
       +
       	securejoin "github.com/cyphar/filepath-securejoin"

     

       14
       14
       +
       	"github.com/urfave/cli/v3"

     

       15
       15
       +
       	"tangled.sh/tangled.sh/core/appview/idresolver"

     

       16
       16
       +
       	"tangled.sh/tangled.sh/core/log"

     

       17
       17
       +
       )

     

       18
       18
       +
       

     

       19
       19
       +
       func Command() *cli.Command {

     

       20
       20
       +
       	return &cli.Command{

     

       21
       21
       +
       		Name:   "guard",

     

       22
       22
       +
       		Usage:  "role-based access control for git over ssh (not for manual use)",

     

       23
       23
       +
       		Action: Run,

     

       24
       24
       +
       		Flags: []cli.Flag{

     

       25
       25
       +
       			&cli.StringFlag{

     

       26
       26
       +
       				Name:     "user",

     

       27
       27
       +
       				Usage:    "allowed git user",

     

       28
       28
       +
       				Required: true,

     

       29
       29
       +
       			},

     

       30
       30
       +
       			&cli.StringFlag{

     

       31
       31
       +
       				Name:  "git-dir",

     

       32
       32
       +
       				Usage: "base directory for git repos",

     

       33
       33
       +
       				Value: "/home/git",

     

       34
       34
       +
       			},

     

       35
       35
       +
       			&cli.StringFlag{

     

       36
       36
       +
       				Name:  "log-path",

     

       37
       37
       +
       				Usage: "path to log file",

     

       38
       38
       +
       				Value: "/home/git/guard.log",

     

       39
       39
       +
       			},

     

       40
       40
       +
       			&cli.StringFlag{

     

       41
       41
       +
       				Name:  "internal-api",

     

       42
       42
       +
       				Usage: "internal API endpoint",

     

       43
       43
       +
       				Value: "http://localhost:5444",

     

       44
       44
       +
       			},

     

       45
       45
       +
       		},

     

       46
       46
       +
       	}

     

       47
       47
       +
       }

     

       48
       48
       +
       

     

       49
       49
       +
       func Run(ctx context.Context, cmd *cli.Command) error {

     

       50
       50
       +
       	l := log.FromContext(ctx)

     

       51
       51
       +
       

     

       52
       52
       +
       	incomingUser := cmd.String("user")

     

       53
       53
       +
       	gitDir := cmd.String("git-dir")

     

       54
       54
       +
       	logPath := cmd.String("log-path")

     

       55
       55
       +
       	endpoint := cmd.String("internal-api")

     

       56
       56
       +
       

     

       57
       57
       +
       	logFile, err := os.OpenFile(logPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)

     

       58
       58
       +
       	if err != nil {

     

       59
       59
       +
       		l.Error("failed to open log file", "error", err)

     

       60
       60
       +
       		return err

     

       61
       61
       +
       	} else {

     

       62
       62
       +
       		fileHandler := slog.NewJSONHandler(logFile, &slog.HandlerOptions{Level: slog.LevelInfo})

     

       63
       63
       +
       		l = slog.New(fileHandler)

     

       64
       64
       +
       	}

     

       65
       65
       +
       

     

       66
       66
       +
       	var clientIP string

     

       67
       67
       +
       	if connInfo := os.Getenv("SSH_CONNECTION"); connInfo != "" {

     

       68
       68
       +
       		parts := strings.Fields(connInfo)

     

       69
       69
       +
       		if len(parts) > 0 {

     

       70
       70
       +
       			clientIP = parts[0]

     

       71
       71
       +
       		}

     

       72
       72
       +
       	}

     

       73
       73
       +
       

     

       74
       74
       +
       	if incomingUser == "" {

     

       75
       75
       +
       		l.Error("access denied: no user specified")

     

       76
       76
       +
       		fmt.Fprintln(os.Stderr, "access denied: no user specified")

     

       77
       77
       +
       		return fmt.Errorf("access denied: no user specified")

     

       78
       78
       +
       	}

     

       79
       79
       +
       

     

       80
       80
       +
       	sshCommand := os.Getenv("SSH_ORIGINAL_COMMAND")

     

       81
       81
       +
       

     

       82
       82
       +
       	l.Info("connection attempt",

     

       83
       83
       +
       		"user", incomingUser,

     

       84
       84
       +
       		"command", sshCommand,

     

       85
       85
       +
       		"client", clientIP)

     

       86
       86
       +
       

     

       87
       87
       +
       	if sshCommand == "" {

     

       88
       88
       +
       		l.Error("access denied: no interactive shells", "user", incomingUser)

     

       89
       89
       +
       		fmt.Fprintln(os.Stderr, "access denied: we don't serve interactive shells :)")

     

       90
       90
       +
       		return fmt.Errorf("access denied: no interactive shells")

     

       91
       91
       +
       	}

     

       92
       92
       +
       

     

       93
       93
       +
       	cmdParts := strings.Fields(sshCommand)

     

       94
       94
       +
       	if len(cmdParts) < 2 {

     

       95
       95
       +
       		l.Error("invalid command format", "command", sshCommand)

     

       96
       96
       +
       		fmt.Fprintln(os.Stderr, "invalid command format")

     

       97
       97
       +
       		return fmt.Errorf("invalid command format")

     

       98
       98
       +
       	}

     

       99
       99
       +
       

     

       100
       100
       +
       	gitCommand := cmdParts[0]

     

       101
       101
       +
       

     

       102
       102
       +
       	// did:foo/repo-name or

     

       103
       103
       +
       	// handle/repo-name or

     

       104
       104
       +
       	// any of the above with a leading slash (/)

     

       105
       105
       +
       

     

       106
       106
       +
       	components := strings.Split(strings.TrimPrefix(strings.Trim(cmdParts[1], "'"), "/"), "/")

     

       107
       107
       +
       	l.Info("command components", "components", components)

     

       108
       108
       +
       

     

       109
       109
       +
       	if len(components) != 2 {

     

       110
       110
       +
       		l.Error("invalid repo format", "components", components)

     

       111
       111
       +
       		fmt.Fprintln(os.Stderr, "invalid repo format, needs <user>/<repo> or /<user>/<repo>")

     

       112
       112
       +
       		return fmt.Errorf("invalid repo format, needs <user>/<repo> or /<user>/<repo>")

     

       113
       113
       +
       	}

     

       114
       114
       +
       

     

       115
       115
       +
       	didOrHandle := components[0]

     

       116
       116
       +
       	did := resolveToDid(ctx, l, didOrHandle)

     

       117
       117
       +
       	repoName := components[1]

     

       118
       118
       +
       	qualifiedRepoName, _ := securejoin.SecureJoin(did, repoName)

     

       119
       119
       +
       

     

       120
       120
       +
       	validCommands := map[string]bool{

     

       121
       121
       +
       		"git-receive-pack":   true,

     

       122
       122
       +
       		"git-upload-pack":    true,

     

       123
       123
       +
       		"git-upload-archive": true,

     

       124
       124
       +
       	}

     

       125
       125
       +
       	if !validCommands[gitCommand] {

     

       126
       126
       +
       		l.Error("access denied: invalid git command", "command", gitCommand)

     

       127
       127
       +
       		fmt.Fprintln(os.Stderr, "access denied: invalid git command")

     

       128
       128
       +
       		return fmt.Errorf("access denied: invalid git command")

     

       129
       129
       +
       	}

     

       130
       130
       +
       

     

       131
       131
       +
       	if gitCommand != "git-upload-pack" {

     

       132
       132
       +
       		if !isPushPermitted(l, incomingUser, qualifiedRepoName, endpoint) {

     

       133
       133
       +
       			l.Error("access denied: user not allowed",

     

       134
       134
       +
       				"did", incomingUser,

     

       135
       135
       +
       				"reponame", qualifiedRepoName)

     

       136
       136
       +
       			fmt.Fprintln(os.Stderr, "access denied: user not allowed")

     

       137
       137
       +
       			return fmt.Errorf("access denied: user not allowed")

     

       138
       138
       +
       		}

     

       139
       139
       +
       	}

     

       140
       140
       +
       

     

       141
       141
       +
       	fullPath, _ := securejoin.SecureJoin(gitDir, qualifiedRepoName)

     

       142
       142
       +
       

     

       143
       143
       +
       	l.Info("processing command",

     

       144
       144
       +
       		"user", incomingUser,

     

       145
       145
       +
       		"command", gitCommand,

     

       146
       146
       +
       		"repo", repoName,

     

       147
       147
       +
       		"fullPath", fullPath,

     

       148
       148
       +
       		"client", clientIP)

     

       149
       149
       +
       

     

       150
       150
       +
       	if gitCommand == "git-upload-pack" {

     

       151
       151
       +
       		fmt.Fprintf(os.Stderr, "\x02%s\n", "Welcome to this knot!")

     

       152
       152
       +
       	} else {

     

       153
       153
       +
       		fmt.Fprintf(os.Stderr, "%s\n", "Welcome to this knot!")

     

       154
       154
       +
       	}

     

       155
       155
       +
       

     

       156
       156
       +
       	gitCmd := exec.Command(gitCommand, fullPath)

     

       157
       157
       +
       	gitCmd.Stdout = os.Stdout

     

       158
       158
       +
       	gitCmd.Stderr = os.Stderr

     

       159
       159
       +
       	gitCmd.Stdin = os.Stdin

     

       160
       160
       +
       

     

       161
       161
       +
       	if err := gitCmd.Run(); err != nil {

     

       162
       162
       +
       		l.Error("command failed", "error", err)

     

       163
       163
       +
       		fmt.Fprintf(os.Stderr, "command failed: %v\n", err)

     

       164
       164
       +
       		return fmt.Errorf("command failed: %v", err)

     

       165
       165
       +
       	}

     

       166
       166
       +
       

     

       167
       167
       +
       	l.Info("command completed",

     

       168
       168
       +
       		"user", incomingUser,

     

       169
       169
       +
       		"command", gitCommand,

     

       170
       170
       +
       		"repo", repoName,

     

       171
       171
       +
       		"success", true)

     

       172
       172
       +
       

     

       173
       173
       +
       	return nil

     

       174
       174
       +
       }

     

       175
       175
       +
       

     

       176
       176
       +
       func resolveToDid(ctx context.Context, l *slog.Logger, didOrHandle string) string {

     

       177
       177
       +
       	resolver := idresolver.DefaultResolver()

     

       178
       178
       +
       	ident, err := resolver.ResolveIdent(ctx, didOrHandle)

     

       179
       179
       +
       	if err != nil {

     

       180
       180
       +
       		l.Error("Error resolving handle", "error", err, "handle", didOrHandle)

     

       181
       181
       +
       		fmt.Fprintf(os.Stderr, "error resolving handle: %v\n", err)

     

       182
       182
       +
       		os.Exit(1)

     

       183
       183
       +
       	}

     

       184
       184
       +
       

     

       185
       185
       +
       	// did:plc:foobarbaz/repo

     

       186
       186
       +
       	return ident.DID.String()

     

       187
       187
       +
       }

     

       188
       188
       +
       

     

       189
       189
       +
       func isPushPermitted(l *slog.Logger, user, qualifiedRepoName, endpoint string) bool {

     

       190
       190
       +
       	u, _ := url.Parse(endpoint + "/push-allowed")

     

       191
       191
       +
       	q := u.Query()

     

       192
       192
       +
       	q.Add("user", user)

     

       193
       193
       +
       	q.Add("repo", qualifiedRepoName)

     

       194
       194
       +
       	u.RawQuery = q.Encode()

     

       195
       195
       +
       

     

       196
       196
       +
       	req, err := http.Get(u.String())

     

       197
       197
       +
       	if err != nil {

     

       198
       198
       +
       		l.Error("Error verifying permissions", "error", err)

     

       199
       199
       +
       		fmt.Fprintf(os.Stderr, "error verifying permissions: %v\n", err)

     

       200
       200
       +
       		os.Exit(1)

     

       201
       201
       +
       	}

     

       202
       202
       +
       

     

       203
       203
       +
       	l.Info("Checking push permission",

     

       204
       204
       +
       		"url", u.String(),

     

       205
       205
       +
       		"status", req.Status)

     

       206
       206
       +
       

     

       207
       207
       +
       	return req.StatusCode == http.StatusNoContent

     

       208
       208
       +
       }

+121

keyfetch/keyfetch.go

···

       1
       1
       +
       package keyfetch

     

       2
       2
       +
       

     

       3
       3
       +
       import (

     

       4
       4
       +
       	"context"

     

       5
       5
       +
       	"encoding/json"

     

       6
       6
       +
       	"fmt"

     

       7
       7
       +
       	"io"

     

       8
       8
       +
       	"net/http"

     

       9
       9
       +
       	"os"

     

       10
       10
       +
       	"strings"

     

       11
       11
       +
       

     

       12
       12
       +
       	"github.com/urfave/cli/v3"

     

       13
       13
       +
       	"tangled.sh/tangled.sh/core/log"

     

       14
       14
       +
       )

     

       15
       15
       +
       

     

       16
       16
       +
       func Command() *cli.Command {

     

       17
       17
       +
       	return &cli.Command{

     

       18
       18
       +
       		Name:   "keys",

     

       19
       19
       +
       		Usage:  "fetch public keys from the knot server",

     

       20
       20
       +
       		Action: Run,

     

       21
       21
       +
       		Flags: []cli.Flag{

     

       22
       22
       +
       			&cli.StringFlag{

     

       23
       23
       +
       				Name:    "output",

     

       24
       24
       +
       				Aliases: []string{"o"},

     

       25
       25
       +
       				Usage:   "output format (table, json, authorized-keys)",

     

       26
       26
       +
       				Value:   "table",

     

       27
       27
       +
       			},

     

       28
       28
       +
       			&cli.StringFlag{

     

       29
       29
       +
       				Name:  "internal-api",

     

       30
       30
       +
       				Usage: "internal API endpoint",

     

       31
       31
       +
       				Value: "http://localhost:5444",

     

       32
       32
       +
       			},

     

       33
       33
       +
       			&cli.StringFlag{

     

       34
       34
       +
       				Name:  "repoguard-path",

     

       35
       35
       +
       				Usage: "path to the repoguard binary",

     

       36
       36
       +
       				Value: "/home/git/repoguard",

     

       37
       37
       +
       			},

     

       38
       38
       +
       			&cli.StringFlag{

     

       39
       39
       +
       				Name:  "git-dir",

     

       40
       40
       +
       				Usage: "base directory for git repos",

     

       41
       41
       +
       				Value: "/home/git",

     

       42
       42
       +
       			},

     

       43
       43
       +
       			&cli.StringFlag{

     

       44
       44
       +
       				Name:  "log-path",

     

       45
       45
       +
       				Usage: "path to log file",

     

       46
       46
       +
       				Value: "/home/git/log",

     

       47
       47
       +
       			},

     

       48
       48
       +
       		},

     

       49
       49
       +
       	}

     

       50
       50
       +
       }

     

       51
       51
       +
       

     

       52
       52
       +
       func Run(ctx context.Context, cmd *cli.Command) error {

     

       53
       53
       +
       	internalApi := cmd.String("internal-api")

     

       54
       54
       +
       	repoguardPath := cmd.String("repoguard-path")

     

       55
       55
       +
       	gitDir := cmd.String("git-dir")

     

       56
       56
       +
       	logPath := cmd.String("log-path")

     

       57
       57
       +
       	output := cmd.String("output")

     

       58
       58
       +
       

     

       59
       59
       +
       	l := log.FromContext(ctx)

     

       60
       60
       +
       

     

       61
       61
       +
       	resp, err := http.Get(internalApi + "/keys")

     

       62
       62
       +
       	if err != nil {

     

       63
       63
       +
       		l.Error("error reaching internal API endpoint; is the knot server running?", "error", err)

     

       64
       64
       +
       		return err

     

       65
       65
       +
       	}

     

       66
       66
       +
       	defer resp.Body.Close()

     

       67
       67
       +
       

     

       68
       68
       +
       	body, err := io.ReadAll(resp.Body)

     

       69
       69
       +
       	if err != nil {

     

       70
       70
       +
       		l.Error("error reading response body", "error", err)

     

       71
       71
       +
       		return err

     

       72
       72
       +
       	}

     

       73
       73
       +
       

     

       74
       74
       +
       	var data []map[string]any

     

       75
       75
       +
       	err = json.Unmarshal(body, &data)

     

       76
       76
       +
       	if err != nil {

     

       77
       77
       +
       		l.Error("error unmarshalling response body", "error", err)

     

       78
       78
       +
       		return err

     

       79
       79
       +
       	}

     

       80
       80
       +
       

     

       81
       81
       +
       	switch output {

     

       82
       82
       +
       	case "json":

     

       83
       83
       +
       		prettyJSON, err := json.MarshalIndent(data, "", "    ")

     

       84
       84
       +
       		if err != nil {

     

       85
       85
       +
       			l.Error("error pretty printing JSON", "error", err)

     

       86
       86
       +
       			return err

     

       87
       87
       +
       		}

     

       88
       88
       +
       

     

       89
       89
       +
       		if _, err := os.Stdout.Write(prettyJSON); err != nil {

     

       90
       90
       +
       			l.Error("error writing to stdout", "error", err)

     

       91
       91
       +
       			return err

     

       92
       92
       +
       		}

     

       93
       93
       +
       	case "authorized-keys":

     

       94
       94
       +
       		formatted := formatKeyData(repoguardPath, gitDir, logPath, internalApi, data)

     

       95
       95
       +
       		_, err := os.Stdout.Write([]byte(formatted))

     

       96
       96
       +
       		if err != nil {

     

       97
       97
       +
       			l.Error("error writing to stdout", "error", err)

     

       98
       98
       +
       			return err

     

       99
       99
       +
       		}

     

       100
       100
       +
       	case "table":

     

       101
       101
       +
       		fmt.Printf("%-40s %-40s\n", "DID", "KEY")

     

       102
       102
       +
       		fmt.Println(strings.Repeat("-", 80))

     

       103
       103
       +
       

     

       104
       104
       +
       		for _, entry := range data {

     

       105
       105
       +
       			did, _ := entry["did"].(string)

     

       106
       106
       +
       			key, _ := entry["key"].(string)

     

       107
       107
       +
       			fmt.Printf("%-40s %-40s\n", did, key)

     

       108
       108
       +
       		}

     

       109
       109
       +
       	}

     

       110
       110
       +
       	return nil

     

       111
       111
       +
       }

     

       112
       112
       +
       

     

       113
       113
       +
       func formatKeyData(repoguardPath, gitDir, logPath, endpoint string, data []map[string]any) string {

     

       114
       114
       +
       	var result string

     

       115
       115
       +
       	for _, entry := range data {

     

       116
       116
       +
       		result += fmt.Sprintf(

     

       117
       117
       +
       			`command="%s -base-dir %s -user %s -log-path %s -internal-api %s",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty %s`+"\n",

     

       118
       118
       +
       			repoguardPath, gitDir, entry["did"], logPath, endpoint, entry["key"])

     

       119
       119
       +
       	}

     

       120
       120
       +
       	return result

     

       121
       121
       +
       }

+84

knotserver/server.go

···

       1
       1
       +
       package knotserver

     

       2
       2
       +
       

     

       3
       3
       +
       import (

     

       4
       4
       +
       	"context"

     

       5
       5
       +
       	"fmt"

     

       6
       6
       +
       	"net/http"

     

       7
       7
       +
       

     

       8
       8
       +
       	"github.com/urfave/cli/v3"

     

       9
       9
       +
       	"tangled.sh/tangled.sh/core/api/tangled"

     

       10
       10
       +
       	"tangled.sh/tangled.sh/core/jetstream"

     

       11
       11
       +
       	"tangled.sh/tangled.sh/core/knotserver/config"

     

       12
       12
       +
       	"tangled.sh/tangled.sh/core/knotserver/db"

     

       13
       13
       +
       	"tangled.sh/tangled.sh/core/log"

     

       14
       14
       +
       	"tangled.sh/tangled.sh/core/rbac"

     

       15
       15
       +
       )

     

       16
       16
       +
       

     

       17
       17
       +
       func Command() *cli.Command {

     

       18
       18
       +
       	return &cli.Command{

     

       19
       19
       +
       		Name:   "server",

     

       20
       20
       +
       		Usage:  "run a knot server",

     

       21
       21
       +
       		Action: Run,

     

       22
       22
       +
       		Description: `

     

       23
       23
       +
       Environment variables:

     

       24
       24
       +
       	KNOT_SERVER_SECRET              (required)

     

       25
       25
       +
       	KNOT_SERVER_HOSTNAME            (required)

     

       26
       26
       +
       	KNOT_SERVER_LISTEN_ADDR         (default: 0.0.0.0:5555)

     

       27
       27
       +
       	KNOT_SERVER_INTERNAL_LISTEN_ADDR (default: 127.0.0.1:5444)

     

       28
       28
       +
       	KNOT_SERVER_DB_PATH             (default: knotserver.db)

     

       29
       29
       +
       	KNOT_SERVER_JETSTREAM_ENDPOINT  (default: wss://jetstream1.us-west.bsky.network/subscribe)

     

       30
       30
       +
       	KNOT_SERVER_DEV                 (default: false)

     

       31
       31
       +
       	KNOT_REPO_SCAN_PATH             (default: /home/git)

     

       32
       32
       +
       	KNOT_REPO_README                (comma-separated list)

     

       33
       33
       +
       	KNOT_REPO_MAIN_BRANCH           (default: main)

     

       34
       34
       +
       	APPVIEW_ENDPOINT                (default: https://tangled.sh)

     

       35
       35
       +
       `,

     

       36
       36
       +
       	}

     

       37
       37
       +
       }

     

       38
       38
       +
       

     

       39
       39
       +
       func Run(ctx context.Context, cmd *cli.Command) error {

     

       40
       40
       +
       	l := log.FromContext(ctx)

     

       41
       41
       +
       

     

       42
       42
       +
       	c, err := config.Load(ctx)

     

       43
       43
       +
       	if err != nil {

     

       44
       44
       +
       		return fmt.Errorf("failed to load config: %w", err)

     

       45
       45
       +
       	}

     

       46
       46
       +
       

     

       47
       47
       +
       	if c.Server.Dev {

     

       48
       48
       +
       		l.Info("running in dev mode, signature verification is disabled")

     

       49
       49
       +
       	}

     

       50
       50
       +
       

     

       51
       51
       +
       	db, err := db.Setup(c.Server.DBPath)

     

       52
       52
       +
       	if err != nil {

     

       53
       53
       +
       		return fmt.Errorf("failed to load db: %w", err)

     

       54
       54
       +
       	}

     

       55
       55
       +
       

     

       56
       56
       +
       	e, err := rbac.NewEnforcer(c.Server.DBPath)

     

       57
       57
       +
       	if err != nil {

     

       58
       58
       +
       		return fmt.Errorf("failed to setup rbac enforcer: %w", err)

     

       59
       59
       +
       	}

     

       60
       60
       +
       

     

       61
       61
       +
       	e.E.EnableAutoSave(true)

     

       62
       62
       +
       

     

       63
       63
       +
       	jc, err := jetstream.NewJetstreamClient(c.Server.JetstreamEndpoint, "knotserver", []string{

     

       64
       64
       +
       		tangled.PublicKeyNSID,

     

       65
       65
       +
       		tangled.KnotMemberNSID,

     

       66
       66
       +
       	}, nil, l, db, true)

     

       67
       67
       +
       	if err != nil {

     

       68
       68
       +
       		l.Error("failed to setup jetstream", "error", err)

     

       69
       69
       +
       	}

     

       70
       70
       +
       

     

       71
       71
       +
       	mux, err := Setup(ctx, c, db, e, jc, l)

     

       72
       72
       +
       	if err != nil {

     

       73
       73
       +
       		return fmt.Errorf("failed to setup server: %w", err)

     

       74
       74
       +
       	}

     

       75
       75
       +
       	imux := Internal(ctx, db, e)

     

       76
       76
       +
       

     

       77
       77
       +
       	l.Info("starting internal server", "address", c.Server.InternalListenAddr)

     

       78
       78
       +
       	go http.ListenAndServe(c.Server.InternalListenAddr, imux)

     

       79
       79
       +
       

     

       80
       80
       +
       	l.Info("starting main server", "address", c.Server.ListenAddr)

     

       81
       81
       +
       	l.Error("server error", "error", http.ListenAndServe(c.Server.ListenAddr, mux))

     

       82
       82
       +
       

     

       83
       83
       +
       	return nil

     

       84
       84
       +
       }