tangled.org
+148
cmd/repoguard/main.go
+148
cmd/repoguard/main.go
···
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package main
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import (
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"flag"
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"fmt"
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"log"
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"os"
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"os/exec"
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"path/filepath"
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"strings"
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"time"
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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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allowedUser = 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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)
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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 *allowedUser == "" {
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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": *allowedUser,
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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: no ssh command provided")
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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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repoName := strings.Trim(cmdParts[1], "'")
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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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}
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if !validCommands[gitCommand] {
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exitWithLog("access denied: invalid git command")
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}
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if !isAllowedUser(*allowedUser, repoName) {
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exitWithLog("access denied: user not allowed")
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}
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fullPath := filepath.Join(*baseDirFlag, repoName)
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fullPath = filepath.Clean(fullPath)
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logEvent("Processing command", map[string]interface{}{
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"user": *allowedUser,
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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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})
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cmd := exec.Command(gitCommand, fullPath)
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cmd.Stdout = os.Stdout
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cmd.Stderr = os.Stderr
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cmd.Stdin = os.Stdin
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if err := cmd.Run(); err != nil {
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exitWithLog(fmt.Sprintf("command failed: %v", err))
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}
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logEvent("Command completed", map[string]interface{}{
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"user": *allowedUser,
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"command": gitCommand,
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"repo": repoName,
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"success": true,
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})
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}
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func initLogger() {
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var err error
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logFile, err = os.OpenFile(*logPathFlag, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600)
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if err != nil {
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fmt.Fprintf(os.Stderr, "failed to open log file: %v\n", err)
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os.Exit(1)
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}
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logger = log.New(logFile, "", 0)
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}
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func logEvent(event string, fields map[string]interface{}) {
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entry := fmt.Sprintf(
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"timestamp=%q event=%q",
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time.Now().Format(time.RFC3339),
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event,
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)
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for k, v := range fields {
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entry += fmt.Sprintf(" %s=%q", k, v)
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}
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logger.Println(entry)
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}
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func exitWithLog(message string) {
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logEvent("Access denied", map[string]interface{}{
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"error": message,
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})
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logFile.Sync()
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fmt.Fprintf(os.Stderr, "error: %s\n", message)
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os.Exit(1)
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}
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func cleanup() {
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if logFile != nil {
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logFile.Sync()
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logFile.Close()
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}
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}
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func isAllowedUser(user, repoPath string) bool {
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pathUser := strings.Split(repoPath, "/")[0]
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return pathUser == user
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}