func attachCmd(cmd *exec.Cmd, ch ssh.Channel) (*sync.WaitGroup, error) {
var wg sync.WaitGroup
wg.Add(3)
stdout, err := cmd.StdoutPipe()
if err != nil {
return nil, err
}
stderr, err := cmd.StderrPipe()
if err != nil {
return nil, err
}
stdin, err := cmd.StdinPipe()
if err != nil {
return nil, err
}
go func() {
defer wg.Done()
io.Copy(stdin, ch)
}()
go func() {
defer wg.Done()
io.Copy(ch.Stderr(), stderr)
}()
go func() {
defer wg.Done()
io.Copy(ch, stdout)
}()
return &wg, nil
}
func (s *sshServer) handleRequests(channel ssh.Channel, in <-chan *ssh.Request) error {
env := make(map[string]string)
for req := range in {
switch req.Type {
default:
log.Printf("unrecognized ssh request type=%q payload=%s wantreply=%t", req.Type, req.Payload, req.WantReply)
req.Reply(false, nil) // unhandled; tell them so
case "env":
var e envReq
if err := ssh.Unmarshal(req.Payload, &e); err != nil {
req.Reply(false, nil)
return err
}
req.Reply(true, nil)
env[string(e.Key)] = string(e.Val)
case "exec":
var e execReq
if err := ssh.Unmarshal(req.Payload, &e); err != nil {
req.Reply(false, nil)
return err
}
req.Reply(true, nil)
var cmdbuf bytes.Buffer
for k, v := range env {
cmdbuf.WriteString(k)
cmdbuf.WriteByte('=')
cmdbuf.WriteString(v)
cmdbuf.WriteByte(' ')
}
cmdbuf.Write(e.Command)
log.Printf("Running command %q", cmdbuf.String())
cmd := &packer.RemoteCmd{Command: cmdbuf.String()}
cmd.Stdout = channel
cmd.Stderr = channel.Stderr()
var rc int
if err := s.comm.Start(cmd); err != nil {
rc = 255 // TODO: What is a better choice here?
} else {
cmd.Wait()
rc = cmd.ExitStatus
}
channel.CloseWrite()
channel.SendRequest("exit-status", false, []byte{0, 0, 0, byte(rc)})
channel.Close()
}
}
return nil
}
func (push Push) Run(command string, ch ssh.Channel) (uint64, error) {
//TODO make "master" be dynamic
code, err := gitShell(ch, ch.Stderr(), command)
if err == nil {
newCommit := getCommit("master")
stream := ch.Stderr()
err = deploy.Run(stream, newCommit)
if err != nil {
return 1, err
}
}
return code, err
}
// plumbCommand connects the exec in/output and the channel in/output.
//
// The sidechannel is for sending errors to logs.
func plumbCommand(cmd *exec.Cmd, channel ssh.Channel, sidechannel io.Writer) *sync.WaitGroup {
var wg sync.WaitGroup
inpipe, _ := cmd.StdinPipe()
go func() {
io.Copy(inpipe, channel)
inpipe.Close()
}()
cmd.Stdout = channel
cmd.Stderr = channel.Stderr()
return &wg
}
func (server *Server) handleRequest(channel ssh.Channel, requests <-chan *ssh.Request, conn *ssh.ServerConn) {
defer func() {
err := channel.Close()
if err != nil {
server.Logger.Errorf("Failed to close SSH Channel from %s due to %s",
conn.RemoteAddr().String(), err)
}
server.Logger.Debugf("Close SSH Channel from %s", conn.RemoteAddr().String())
}()
for req := range requests {
server.Logger.Debugf("Received new SSH Request (type = %s) from %s", req.Type, conn.RemoteAddr().String())
switch req.Type {
case "exec":
server.handleExecRequest(channel, req, conn)
default:
var err error
if req.Type == "env" {
_, err = channel.Stderr().Write([]byte("error: Pages does not support SendEnv.\n"))
} else {
_, err = channel.Write([]byte("You've successfully authenticated, but Pages does not provide shell access.\n"))
}
if err != nil && err != io.EOF {
server.Logger.Errorf("Failed to Talk to SSH Request due to %s", err)
}
err = req.Reply(false, nil)
if err != nil && err != io.EOF {
server.Logger.Errorf("Failed to Reply false to SSH Request due to %s", err)
}
err = channel.Close()
if err != nil && err != io.EOF {
server.Logger.Errorf("Failed to close SSH Request due to %s", err)
}
server.Logger.Errorf("Close SSH Request due to unsupported SSH Request type: %s", req.Type)
}
return
}
}
// answer handles answering requests and channel requests
//
// Currently, an exec must be either "ping", "git-receive-pack" or
// "git-upload-pack". Anything else will result in a failure response. Right
// now, we leave the channel open on failure because it is unclear what the
// correct behavior for a failed exec is.
//
// Support for setting environment variables via `env` has been disabled.
func (s *server) answer(channel ssh.Channel, requests <-chan *ssh.Request, condata string, sshconn *ssh.ServerConn) error {
defer channel.Close()
// Answer all the requests on this connection.
for req := range requests {
ok := false
switch req.Type {
case "env":
o := &EnvVar{}
ssh.Unmarshal(req.Payload, o)
log.Info("Key='%s', Value='%s'\n", o.Name, o.Value)
req.Reply(true, nil)
case "exec":
clean := cleanExec(req.Payload)
parts := strings.SplitN(clean, " ", 2)
switch parts[0] {
case "ping":
err := Ping(channel, req)
if err != nil {
log.Info("Error pinging: %s", err)
}
return err
case "git-receive-pack", "git-upload-pack":
if len(parts) < 2 {
log.Info("Expected two-part command.")
req.Reply(ok, nil)
break
}
repoName, err := cleanRepoName(parts[1])
if err != nil {
log.Err("Illegal repo name: %s.", err)
channel.Stderr().Write([]byte("No repo given"))
return err
}
wrapErr := wrapInLock(s.pushLock, repoName, time.Duration(0), s.runReceive(req, sshconn, channel, repoName, parts, condata))
if wrapErr == errAlreadyLocked {
log.Info(multiplePush)
// The error must be in git format
if pktErr := gitPktLine(channel, fmt.Sprintf("ERR %v\n", multiplePush)); pktErr != nil {
log.Err("Failed to write to channel: %s", err)
}
sendExitStatus(1, channel)
req.Reply(false, nil)
return nil
}
var xs uint32
if wrapErr != nil {
log.Err("Failed git receive: %v", err)
xs = 1
}
sendExitStatus(xs, channel)
return nil
default:
log.Info("Illegal command is '%s'\n", clean)
req.Reply(false, nil)
return nil
}
if err := sendExitStatus(0, channel); err != nil {
log.Err("Failed to write exit status: %s", err)
}
return nil
default:
// We simply ignore all of the other cases and leave the
// channel open to take additional requests.
log.Info("Received request of type %s\n", req.Type)
req.Reply(false, nil)
}
}
return nil
}
func (pull Pull) Run(command string, ch ssh.Channel) (uint64, error) {
return gitShell(ch, ch.Stderr(), command)
}
// Receive receives a Git repo.
// This will only work for git-receive-pack.
func Receive(
repo, operation, gitHome string,
channel ssh.Channel,
fingerprint, username, conndata, receivetype string) error {
log.Info("receiving git repo name: %s, operation: %s, fingerprint: %s, user: %s", repo, operation, fingerprint, username)
if receivetype == "mock" {
channel.Write([]byte("OK"))
return nil
}
repoPath := filepath.Join(gitHome, repo)
log.Info("creating repo directory %s", repoPath)
if _, err := createRepo(repoPath); err != nil {
err = fmt.Errorf("Did not create new repo (%s)", err)
return err
}
log.Info("writing pre-receive hook under %s", repoPath)
if err := createPreReceiveHook(gitHome, repoPath); err != nil {
err = fmt.Errorf("Did not write pre-receive hook (%s)", err)
return err
}
cmd := exec.Command("git-shell", "-c", fmt.Sprintf("%s '%s'", operation, repo))
log.Info(strings.Join(cmd.Args, " "))
var errbuff bytes.Buffer
cmd.Dir = gitHome
cmd.Env = []string{
fmt.Sprintf("RECEIVE_USER=%s", username),
fmt.Sprintf("RECEIVE_REPO=%s", repo),
fmt.Sprintf("RECEIVE_FINGERPRINT=%s", fingerprint),
fmt.Sprintf("SSH_ORIGINAL_COMMAND=%s '%s'", operation, repo),
fmt.Sprintf("SSH_CONNECTION=%s", conndata),
}
cmd.Env = append(cmd.Env, os.Environ()...)
log.Debug("Working Dir: %s", cmd.Dir)
log.Debug("Environment: %s", strings.Join(cmd.Env, ","))
inpipe, err := cmd.StdinPipe()
if err != nil {
return err
}
cmd.Stdout = channel
cmd.Stderr = io.MultiWriter(channel.Stderr(), &errbuff)
if err := cmd.Start(); err != nil {
err = fmt.Errorf("Failed to start git pre-receive hook: %s (%s)", err, errbuff.Bytes())
return err
}
if _, err := io.Copy(inpipe, channel); err != nil {
err = fmt.Errorf("Failed to write git objects into the git pre-receive hook (%s)", err)
return err
}
fmt.Println("Waiting for git-receive to run.")
fmt.Println("Waiting for deploy.")
if err := cmd.Wait(); err != nil {
err = fmt.Errorf("Failed to run git pre-receive hook: %s (%s)", errbuff.Bytes(), err)
return err
}
if errbuff.Len() > 0 {
log.Err("Unreported error: %s", errbuff.Bytes())
return errors.New(errbuff.String())
}
log.Info("Deploy complete.")
return nil
}
func (server *Server) handleExecRequest(channel ssh.Channel, request *ssh.Request, conn *ssh.ServerConn) {
doReply := func(ok bool) {
err := request.Reply(ok, nil)
if err != nil {
server.Logger.Errorf("Failed to reply %t to SSH Request from %s due to %s",
ok, conn.RemoteAddr().String(), err)
}
server.Logger.Debugf("Reply to SSH Request `%t` from %s", ok, conn.RemoteAddr().String())
}
if len(request.Payload) < 4 {
server.Logger.Errorf("Payload must not be shorter than 4 bytes, but only %d bytes", len(request.Payload))
doReply(false)
return
}
header := request.Payload[:4]
cmdLen := int64(binary.BigEndian.Uint32(header))
if int64(len(request.Payload)) < 4+cmdLen {
server.Logger.Errorf("Payload must not be shorter than %d bytes, but only %d bytes", 4+cmdLen, len(request.Payload))
doReply(false)
return
}
cmd := request.Payload[4 : 4+cmdLen]
server.Logger.Debugf("Execute command `%s` via SSH from %s",
string(cmd), conn.RemoteAddr().String())
shellCmd := exec.Command(server.Config.ShellPath, "-c", string(cmd))
stdinPipe, err := shellCmd.StdinPipe()
if err != nil {
server.Logger.Errorf("Failed to create STDIN pipe error for command: %s", err)
doReply(false)
return
}
defer stdinPipe.Close()
stdoutPipe, err := shellCmd.StdoutPipe()
if err != nil {
server.Logger.Errorf("Failed to create STDOUT pipe error for command: %s", err)
doReply(false)
return
}
defer stdoutPipe.Close()
stderrPipe, err := shellCmd.StderrPipe()
if err != nil {
server.Logger.Errorf("Failed to create STDERR pipe error for command: %s", err)
doReply(false)
return
}
defer stderrPipe.Close()
sendExitStatus := func() {
channel.SendRequest("exit-status", false, []byte{0, 0, 0, 0})
server.Logger.Debugf("Sent exit status 0 to %s", conn.RemoteAddr().String())
}
var once sync.Once
go func() {
io.Copy(stdinPipe, channel)
once.Do(sendExitStatus)
}()
go func() {
io.Copy(channel, stdoutPipe)
once.Do(sendExitStatus)
}()
go func() {
io.Copy(channel.Stderr(), stderrPipe)
once.Do(sendExitStatus)
}()
err = shellCmd.Start()
if err != nil {
server.Logger.Errorf("Close SSH Channel from %s due to command error: %s", conn.RemoteAddr().String(), err)
doReply(false)
return
}
doReply(true)
_, err = shellCmd.Process.Wait()
if err != nil {
_, ok := err.(*exec.ExitError)
if !ok {
server.Logger.Errorf("Failed to wait command(PID = %d) due to %s", shellCmd.Process.Pid, err)
}
return
}
}
func pipe(ch ssh.Channel, client *ssh.Client, session *ssh.Session, command string) (int, error) {
targetStderr, err := session.StderrPipe()
if err != nil {
return -1, errors.New("fail to pipe stderr: " + err.Error())
}
targetStdout, err := session.StdoutPipe()
if err != nil {
return -1, errors.New("fail to pipe stdout: " + err.Error())
}
targetStdin, err := session.StdinPipe()
if err != nil {
return -1, errors.New("fail to pipe stdin: " + err.Error())
}
go io.Copy(targetStdin, ch)
go io.Copy(ch.Stderr(), targetStderr)
go io.Copy(ch, targetStdout)
err = session.Start(command)
if err != nil {
ch.Write([]byte("Error when starting '" + command + "': " + err.Error()))
ch.Close()
}
err = session.Wait()
if err != nil {
if err, ok := err.(*ssh.ExitError); ok {
return err.ExitStatus(), nil
} else {
return -1, errors.New("failed to wait ssh command: " + err.Error())
}
}
return 0, nil
}
