forgejo/cmd/serv.go
zeripath 1d04e8641d
Set Setpgid on child git processes (#19865)
When Gitea is running as PID 1 git will occassionally orphan child processes leading
to (defunct) processes. This PR simply sets Setpgid to true on these child processes
meaning that these defunct processes will also be correctly reaped.

Fix #19077

Signed-off-by: Andrew Thornton <art27@cantab.net>
2022-06-03 15:36:18 +01:00

328 lines
10 KiB
Go

// Copyright 2014 The Gogs Authors. All rights reserved.
// Copyright 2016 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package cmd
import (
"fmt"
"net/http"
"net/url"
"os"
"os/exec"
"regexp"
"strconv"
"strings"
"time"
"code.gitea.io/gitea/models"
asymkey_model "code.gitea.io/gitea/models/asymkey"
"code.gitea.io/gitea/models/perm"
"code.gitea.io/gitea/modules/git"
"code.gitea.io/gitea/modules/json"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/pprof"
"code.gitea.io/gitea/modules/private"
"code.gitea.io/gitea/modules/process"
repo_module "code.gitea.io/gitea/modules/repository"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/services/lfs"
"github.com/golang-jwt/jwt/v4"
"github.com/kballard/go-shellquote"
"github.com/urfave/cli"
)
const (
lfsAuthenticateVerb = "git-lfs-authenticate"
)
// CmdServ represents the available serv sub-command.
var CmdServ = cli.Command{
Name: "serv",
Usage: "This command should only be called by SSH shell",
Description: `Serv provide access auth for repositories`,
Action: runServ,
Flags: []cli.Flag{
cli.BoolFlag{
Name: "enable-pprof",
},
cli.BoolFlag{
Name: "debug",
},
},
}
func setup(logPath string, debug bool) {
_ = log.DelLogger("console")
if debug {
_ = log.NewLogger(1000, "console", "console", `{"level":"trace","stacktracelevel":"NONE","stderr":true}`)
} else {
_ = log.NewLogger(1000, "console", "console", `{"level":"fatal","stacktracelevel":"NONE","stderr":true}`)
}
setting.LoadFromExisting()
if debug {
setting.RunMode = "dev"
}
}
var (
allowedCommands = map[string]perm.AccessMode{
"git-upload-pack": perm.AccessModeRead,
"git-upload-archive": perm.AccessModeRead,
"git-receive-pack": perm.AccessModeWrite,
lfsAuthenticateVerb: perm.AccessModeNone,
}
alphaDashDotPattern = regexp.MustCompile(`[^\w-\.]`)
)
func fail(userMessage, logMessage string, args ...interface{}) error {
// There appears to be a chance to cause a zombie process and failure to read the Exit status
// if nothing is outputted on stdout.
fmt.Fprintln(os.Stdout, "")
fmt.Fprintln(os.Stderr, "Gitea:", userMessage)
if len(logMessage) > 0 {
if !setting.IsProd {
fmt.Fprintf(os.Stderr, logMessage+"\n", args...)
}
}
ctx, cancel := installSignals()
defer cancel()
if len(logMessage) > 0 {
_ = private.SSHLog(ctx, true, fmt.Sprintf(logMessage+": ", args...))
}
return cli.NewExitError("", 1)
}
func runServ(c *cli.Context) error {
ctx, cancel := installSignals()
defer cancel()
// FIXME: This needs to internationalised
setup("serv.log", c.Bool("debug"))
if setting.SSH.Disabled {
println("Gitea: SSH has been disabled")
return nil
}
if len(c.Args()) < 1 {
if err := cli.ShowSubcommandHelp(c); err != nil {
fmt.Printf("error showing subcommand help: %v\n", err)
}
return nil
}
keys := strings.Split(c.Args()[0], "-")
if len(keys) != 2 || keys[0] != "key" {
return fail("Key ID format error", "Invalid key argument: %s", c.Args()[0])
}
keyID, err := strconv.ParseInt(keys[1], 10, 64)
if err != nil {
return fail("Key ID format error", "Invalid key argument: %s", c.Args()[1])
}
cmd := os.Getenv("SSH_ORIGINAL_COMMAND")
if len(cmd) == 0 {
key, user, err := private.ServNoCommand(ctx, keyID)
if err != nil {
return fail("Internal error", "Failed to check provided key: %v", err)
}
switch key.Type {
case asymkey_model.KeyTypeDeploy:
println("Hi there! You've successfully authenticated with the deploy key named " + key.Name + ", but Gitea does not provide shell access.")
case asymkey_model.KeyTypePrincipal:
println("Hi there! You've successfully authenticated with the principal " + key.Content + ", but Gitea does not provide shell access.")
default:
println("Hi there, " + user.Name + "! You've successfully authenticated with the key named " + key.Name + ", but Gitea does not provide shell access.")
}
println("If this is unexpected, please log in with password and setup Gitea under another user.")
return nil
} else if c.Bool("debug") {
log.Debug("SSH_ORIGINAL_COMMAND: %s", os.Getenv("SSH_ORIGINAL_COMMAND"))
}
words, err := shellquote.Split(cmd)
if err != nil {
return fail("Error parsing arguments", "Failed to parse arguments: %v", err)
}
if len(words) < 2 {
if git.CheckGitVersionAtLeast("2.29") == nil {
// for AGit Flow
if cmd == "ssh_info" {
fmt.Print(`{"type":"gitea","version":1}`)
return nil
}
}
return fail("Too few arguments", "Too few arguments in cmd: %s", cmd)
}
verb := words[0]
repoPath := words[1]
if repoPath[0] == '/' {
repoPath = repoPath[1:]
}
var lfsVerb string
if verb == lfsAuthenticateVerb {
if !setting.LFS.StartServer {
return fail("Unknown git command", "LFS authentication request over SSH denied, LFS support is disabled")
}
if len(words) > 2 {
lfsVerb = words[2]
}
}
// LowerCase and trim the repoPath as that's how they are stored.
repoPath = strings.ToLower(strings.TrimSpace(repoPath))
rr := strings.SplitN(repoPath, "/", 2)
if len(rr) != 2 {
return fail("Invalid repository path", "Invalid repository path: %v", repoPath)
}
username := strings.ToLower(rr[0])
reponame := strings.ToLower(strings.TrimSuffix(rr[1], ".git"))
if alphaDashDotPattern.MatchString(reponame) {
return fail("Invalid repo name", "Invalid repo name: %s", reponame)
}
if c.Bool("enable-pprof") {
if err := os.MkdirAll(setting.PprofDataPath, os.ModePerm); err != nil {
return fail("Error while trying to create PPROF_DATA_PATH", "Error while trying to create PPROF_DATA_PATH: %v", err)
}
stopCPUProfiler, err := pprof.DumpCPUProfileForUsername(setting.PprofDataPath, username)
if err != nil {
return fail("Internal Server Error", "Unable to start CPU profile: %v", err)
}
defer func() {
stopCPUProfiler()
err := pprof.DumpMemProfileForUsername(setting.PprofDataPath, username)
if err != nil {
_ = fail("Internal Server Error", "Unable to dump Mem Profile: %v", err)
}
}()
}
requestedMode, has := allowedCommands[verb]
if !has {
return fail("Unknown git command", "Unknown git command %s", verb)
}
if verb == lfsAuthenticateVerb {
if lfsVerb == "upload" {
requestedMode = perm.AccessModeWrite
} else if lfsVerb == "download" {
requestedMode = perm.AccessModeRead
} else {
return fail("Unknown LFS verb", "Unknown lfs verb %s", lfsVerb)
}
}
results, err := private.ServCommand(ctx, keyID, username, reponame, requestedMode, verb, lfsVerb)
if err != nil {
if private.IsErrServCommand(err) {
errServCommand := err.(private.ErrServCommand)
if errServCommand.StatusCode != http.StatusInternalServerError {
return fail("Unauthorized", "%s", errServCommand.Error())
}
return fail("Internal Server Error", "%s", errServCommand.Error())
}
return fail("Internal Server Error", "%s", err.Error())
}
os.Setenv(repo_module.EnvRepoIsWiki, strconv.FormatBool(results.IsWiki))
os.Setenv(repo_module.EnvRepoName, results.RepoName)
os.Setenv(repo_module.EnvRepoUsername, results.OwnerName)
os.Setenv(repo_module.EnvPusherName, results.UserName)
os.Setenv(repo_module.EnvPusherEmail, results.UserEmail)
os.Setenv(repo_module.EnvPusherID, strconv.FormatInt(results.UserID, 10))
os.Setenv(repo_module.EnvRepoID, strconv.FormatInt(results.RepoID, 10))
os.Setenv(repo_module.EnvPRID, fmt.Sprintf("%d", 0))
os.Setenv(repo_module.EnvDeployKeyID, fmt.Sprintf("%d", results.DeployKeyID))
os.Setenv(repo_module.EnvKeyID, fmt.Sprintf("%d", results.KeyID))
os.Setenv(repo_module.EnvAppURL, setting.AppURL)
// LFS token authentication
if verb == lfsAuthenticateVerb {
url := fmt.Sprintf("%s%s/%s.git/info/lfs", setting.AppURL, url.PathEscape(results.OwnerName), url.PathEscape(results.RepoName))
now := time.Now()
claims := lfs.Claims{
RegisteredClaims: jwt.RegisteredClaims{
ExpiresAt: jwt.NewNumericDate(now.Add(setting.LFS.HTTPAuthExpiry)),
NotBefore: jwt.NewNumericDate(now),
},
RepoID: results.RepoID,
Op: lfsVerb,
UserID: results.UserID,
}
token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
// Sign and get the complete encoded token as a string using the secret
tokenString, err := token.SignedString(setting.LFS.JWTSecretBytes)
if err != nil {
return fail("Internal error", "Failed to sign JWT token: %v", err)
}
tokenAuthentication := &models.LFSTokenResponse{
Header: make(map[string]string),
Href: url,
}
tokenAuthentication.Header["Authorization"] = fmt.Sprintf("Bearer %s", tokenString)
enc := json.NewEncoder(os.Stdout)
err = enc.Encode(tokenAuthentication)
if err != nil {
return fail("Internal error", "Failed to encode LFS json response: %v", err)
}
return nil
}
// Special handle for Windows.
if setting.IsWindows {
verb = strings.Replace(verb, "-", " ", 1)
}
var gitcmd *exec.Cmd
verbs := strings.Split(verb, " ")
if len(verbs) == 2 {
gitcmd = exec.CommandContext(ctx, verbs[0], verbs[1], repoPath)
} else {
gitcmd = exec.CommandContext(ctx, verb, repoPath)
}
// Check if setting.RepoRootPath exists. It could be the case that it doesn't exist, this can happen when
// `[repository]` `ROOT` is a relative path and $GITEA_WORK_DIR isn't passed to the SSH connection.
if _, err := os.Stat(setting.RepoRootPath); err != nil {
if os.IsNotExist(err) {
return fail("Incorrect configuration.",
"Directory `[repository]` `ROOT` %s was not found, please check if $GITEA_WORK_DIR is passed to the SSH connection or make `[repository]` `ROOT` an absolute value.", setting.RepoRootPath)
}
}
process.SetSysProcAttribute(gitcmd)
gitcmd.Dir = setting.RepoRootPath
gitcmd.Stdout = os.Stdout
gitcmd.Stdin = os.Stdin
gitcmd.Stderr = os.Stderr
if err = gitcmd.Run(); err != nil {
return fail("Internal error", "Failed to execute git command: %v", err)
}
// Update user key activity.
if results.KeyID > 0 {
if err = private.UpdatePublicKeyInRepo(ctx, results.KeyID, results.RepoID); err != nil {
return fail("Internal error", "UpdatePublicKeyInRepo: %v", err)
}
}
return nil
}