switch to use gliderlabs/ssh for builtin server (#7250)

resolves git conflicts from #3896 (credit to @belak, in case github doesn't keep original author during squash)

Co-Authored-By: Matti Ranta <techknowlogick@gitea.io>
release/v1.10
techknowlogick 5 years ago committed by GitHub
parent c44f0b1c76
commit d0ec940dd7
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

@ -40,7 +40,7 @@ require (
github.com/facebookgo/stack v0.0.0-20160209184415-751773369052 // indirect
github.com/facebookgo/stats v0.0.0-20151006221625-1b76add642e4 // indirect
github.com/facebookgo/subset v0.0.0-20150612182917-8dac2c3c4870 // indirect
github.com/gliderlabs/ssh v0.1.4 // indirect
github.com/gliderlabs/ssh v0.2.2
github.com/glycerine/go-unsnap-stream v0.0.0-20180323001048-9f0cb55181dd // indirect
github.com/glycerine/goconvey v0.0.0-20190315024820-982ee783a72e // indirect
github.com/go-macaron/binding v0.0.0-20160711225916-9440f336b443
@ -110,11 +110,11 @@ require (
github.com/yohcop/openid-go v0.0.0-20160914080427-2c050d2dae53
go.etcd.io/bbolt v1.3.2 // indirect
golang.org/x/crypto v0.0.0-20190618222545-ea8f1a30c443
golang.org/x/net v0.0.0-20190613194153-d28f0bde5980
golang.org/x/net v0.0.0-20190619014844-b5b0513f8c1b
golang.org/x/oauth2 v0.0.0-20181101160152-c453e0c75759
golang.org/x/sys v0.0.0-20190618155005-516e3c20635f
golang.org/x/sys v0.0.0-20190620070143-6f217b454f45
golang.org/x/text v0.3.2
golang.org/x/tools v0.0.0-20190618163018-fdf1049a943a // indirect
golang.org/x/tools v0.0.0-20190620154339-431033348dd0 // indirect
gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc // indirect
gopkg.in/asn1-ber.v1 v1.0.0-20150924051756-4e86f4367175 // indirect
gopkg.in/bufio.v1 v1.0.0-20140618132640-567b2bfa514e // indirect

@ -100,8 +100,8 @@ github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568/go.mod h1:xEzjJPgXI
github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
github.com/gliderlabs/ssh v0.1.3/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
github.com/gliderlabs/ssh v0.1.4 h1:5N8AYXpaQAPy0L7linKa5aI+WRfyYagAhjksVzxh+mI=
github.com/gliderlabs/ssh v0.1.4/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
github.com/gliderlabs/ssh v0.2.2 h1:6zsha5zo/TWhRhwqCD3+EarCAgZ2yN28ipRnGPnwkI0=
github.com/gliderlabs/ssh v0.2.2/go.mod h1:U7qILu1NlMHj9FlMhZLlkCdDnU1DBEAqr0aevW3Awn0=
github.com/glycerine/go-unsnap-stream v0.0.0-20180323001048-9f0cb55181dd h1:r04MMPyLHj/QwZuMJ5+7tJcBr1AQjpiAK/rZWRrQT7o=
github.com/glycerine/go-unsnap-stream v0.0.0-20180323001048-9f0cb55181dd/go.mod h1:/20jfyN9Y5QPEAprSgKAUr+glWDY39ZiUEAYOEv5dsE=
github.com/glycerine/goconvey v0.0.0-20190315024820-982ee783a72e h1:SiEs4J3BKVIeaWrH3tKaz3QLZhJ68iJ/A4xrzIoE5+Y=
@ -369,8 +369,8 @@ golang.org/x/net v0.0.0-20181114220301-adae6a3d119a/go.mod h1:mL1N/T3taQHkDXs73r
golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20190502183928-7f726cade0ab/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20190613194153-d28f0bde5980 h1:dfGZHvZk057jK2MCeWus/TowKpJ8y4AmooUzdBSR9GU=
golang.org/x/net v0.0.0-20190613194153-d28f0bde5980/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/net v0.0.0-20190619014844-b5b0513f8c1b h1:lkjdUzSyJ5P1+eal9fxXX9Xg2BTfswsonKUse48C0uE=
golang.org/x/net v0.0.0-20190619014844-b5b0513f8c1b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/oauth2 v0.0.0-20180620175406-ef147856a6dd/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
golang.org/x/oauth2 v0.0.0-20181101160152-c453e0c75759 h1:TMrx+Qdx7uJAeUbv15N72h5Hmyb5+VDjEiMufAEAM04=
@ -395,15 +395,15 @@ golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e h1:nFYrTHrdrAOpShe27kaFHjsqY
golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20190618155005-516e3c20635f h1:dHNZYIYdq2QuU6w73vZ/DzesPbVlZVYZTtTZmrnsbQ8=
golang.org/x/sys v0.0.0-20190618155005-516e3c20635f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/sys v0.0.0-20190620070143-6f217b454f45 h1:Dl2hc890lrizvUppGbRWhnIh2f8jOTCQpY5IKWRS0oM=
golang.org/x/sys v0.0.0-20190620070143-6f217b454f45/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
golang.org/x/tools v0.0.0-20190618163018-fdf1049a943a h1:aQmaYPOmKItb96VioBrTlYay5tSNUdKAFEhPCWMeLSM=
golang.org/x/tools v0.0.0-20190618163018-fdf1049a943a/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
golang.org/x/tools v0.0.0-20190620154339-431033348dd0 h1:qUGDNmGEM+ZBtwF9vuzEv+9nQQPL+l/oNBZ+DCDTAyo=
golang.org/x/tools v0.0.0-20190620154339-431033348dd0/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
google.golang.org/appengine v1.2.0 h1:S0iUepdCWODXRvtE+gcRDd15L+k+k1AiHlMiMjefH24=
google.golang.org/appengine v1.2.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=

@ -34,6 +34,7 @@ LFS_CONTENT_PATH = data/lfs-mssql
OFFLINE_MODE = false
LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w
APP_DATA_PATH = integrations/gitea-integration-mssql/data
BUILTIN_SSH_SERVER_USER = git
[mailer]
ENABLED = true

@ -34,6 +34,7 @@ LFS_CONTENT_PATH = data/lfs-mysql
OFFLINE_MODE = false
LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w
APP_DATA_PATH = integrations/gitea-integration-mysql/data
BUILTIN_SSH_SERVER_USER = git
[mailer]
ENABLED = true

@ -34,6 +34,7 @@ LFS_CONTENT_PATH = data/lfs-mysql8
OFFLINE_MODE = false
LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w
APP_DATA_PATH = integrations/gitea-integration-mysql8/data
BUILTIN_SSH_SERVER_USER = git
[mailer]
ENABLED = false

@ -34,6 +34,7 @@ LFS_CONTENT_PATH = data/lfs-pgsql
OFFLINE_MODE = false
LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w
APP_DATA_PATH = integrations/gitea-integration-pgsql/data
BUILTIN_SSH_SERVER_USER = git
[mailer]
ENABLED = true

@ -73,7 +73,7 @@ func TestViewRepo1CloneLinkAuthorized(t *testing.T) {
assert.Equal(t, setting.AppURL+"user2/repo1.git", link)
link, exists = htmlDoc.doc.Find("#repo-clone-ssh").Attr("data-link")
assert.True(t, exists, "The template has changed")
sshURL := fmt.Sprintf("ssh://%s@%s:%d/user2/repo1.git", setting.RunUser, setting.SSH.Domain, setting.SSH.Port)
sshURL := fmt.Sprintf("ssh://%s@%s:%d/user2/repo1.git", setting.SSH.BuiltinServerUser, setting.SSH.Domain, setting.SSH.Port)
assert.Equal(t, sshURL, link)
}

@ -31,6 +31,7 @@ OFFLINE_MODE = false
LFS_JWT_SECRET = Tv_MjmZuHqpIY6GFl12ebgkRAMt4RlWt0v4EHKSXO0w
APP_DATA_PATH = integrations/gitea-integration-sqlite/data
ENABLE_GZIP = true
BUILTIN_SSH_SERVER_USER = git
[mailer]
ENABLED = true

@ -1,4 +1,3 @@
// Copyright 2014 The Gogs Authors. All rights reserved.
// Copyright 2017 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.
@ -10,178 +9,157 @@ import (
"crypto/rsa"
"crypto/x509"
"encoding/pem"
"fmt"
"io"
"io/ioutil"
"net"
"os"
"os/exec"
"path/filepath"
"strings"
"github.com/Unknwon/com"
"golang.org/x/crypto/ssh"
"sync"
"syscall"
"code.gitea.io/gitea/models"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
"github.com/Unknwon/com"
"github.com/gliderlabs/ssh"
gossh "golang.org/x/crypto/ssh"
)
func cleanCommand(cmd string) string {
i := strings.Index(cmd, "git")
if i == -1 {
return cmd
type contextKey string
const giteaKeyID = contextKey("gitea-key-id")
func getExitStatusFromError(err error) int {
if err == nil {
return 0
}
return cmd[i:]
}
func handleServerConn(keyID string, chans <-chan ssh.NewChannel) {
for newChan := range chans {
if newChan.ChannelType() != "session" {
err := newChan.Reject(ssh.UnknownChannelType, "unknown channel type")
if err != nil {
log.Error("Error rejecting channel: %v", err)
}
continue
}
exitErr, ok := err.(*exec.ExitError)
if !ok {
return 1
}
ch, reqs, err := newChan.Accept()
if err != nil {
log.Error("Error accepting channel: %v", err)
continue
waitStatus, ok := exitErr.Sys().(syscall.WaitStatus)
if !ok {
// This is a fallback and should at least let us return something useful
// when running on Windows, even if it isn't completely accurate.
if exitErr.Success() {
return 0
}
go func(in <-chan *ssh.Request) {
defer func() {
if err = ch.Close(); err != nil {
log.Error("Close: %v", err)
}
}()
for req := range in {
payload := cleanCommand(string(req.Payload))
switch req.Type {
case "exec":
cmdName := strings.TrimLeft(payload, "'()")
log.Trace("SSH: Payload: %v", cmdName)
args := []string{"serv", "key-" + keyID, "--config=" + setting.CustomConf}
log.Trace("SSH: Arguments: %v", args)
cmd := exec.Command(setting.AppPath, args...)
cmd.Env = append(
os.Environ(),
"SSH_ORIGINAL_COMMAND="+cmdName,
"SKIP_MINWINSVC=1",
)
stdout, err := cmd.StdoutPipe()
if err != nil {
log.Error("SSH: StdoutPipe: %v", err)
return
}
stderr, err := cmd.StderrPipe()
if err != nil {
log.Error("SSH: StderrPipe: %v", err)
return
}
input, err := cmd.StdinPipe()
if err != nil {
log.Error("SSH: StdinPipe: %v", err)
return
}
// FIXME: check timeout
if err = cmd.Start(); err != nil {
log.Error("SSH: Start: %v", err)
return
}
err = req.Reply(true, nil)
if err != nil {
log.Error("SSH: Reply: %v", err)
}
go func() {
_, err = io.Copy(input, ch)
if err != nil {
log.Error("SSH: Copy: %v", err)
}
}()
_, err = io.Copy(ch, stdout)
if err != nil {
log.Error("SSH: Copy: %v", err)
}
_, err = io.Copy(ch.Stderr(), stderr)
if err != nil {
log.Error("SSH: Copy: %v", err)
}
if err = cmd.Wait(); err != nil {
log.Error("SSH: Wait: %v", err)
return
}
_, err = ch.SendRequest("exit-status", false, []byte{0, 0, 0, 0})
if err != nil {
log.Error("SSH: SendRequest: %v", err)
}
return
default:
}
}
}(reqs)
return 1
}
return waitStatus.ExitStatus()
}
func listen(config *ssh.ServerConfig, host string, port int) {
listener, err := net.Listen("tcp", host+":"+com.ToStr(port))
func sessionHandler(session ssh.Session) {
keyID := session.Context().Value(giteaKeyID).(int64)
command := session.RawCommand()
log.Trace("SSH: Payload: %v", command)
args := []string{"serv", "key-" + com.ToStr(keyID), "--config=" + setting.CustomConf}
log.Trace("SSH: Arguments: %v", args)
cmd := exec.Command(setting.AppPath, args...)
cmd.Env = append(
os.Environ(),
"SSH_ORIGINAL_COMMAND="+command,
"SKIP_MINWINSVC=1",
)
stdout, err := cmd.StdoutPipe()
if err != nil {
log.Fatal("Failed to start SSH server: %v", err)
log.Error("SSH: StdoutPipe: %v", err)
return
}
for {
// Once a ServerConfig has been configured, connections can be accepted.
conn, err := listener.Accept()
if err != nil {
log.Error("SSH: Error accepting incoming connection: %v", err)
continue
stderr, err := cmd.StderrPipe()
if err != nil {
log.Error("SSH: StderrPipe: %v", err)
return
}
stdin, err := cmd.StdinPipe()
if err != nil {
log.Error("SSH: StdinPipe: %v", err)
return
}
wg := &sync.WaitGroup{}
wg.Add(2)
if err = cmd.Start(); err != nil {
log.Error("SSH: Start: %v", err)
return
}
go func() {
defer stdin.Close()
if _, err := io.Copy(stdin, session); err != nil {
log.Error("Failed to write session to stdin. %s", err)
}
}()
go func() {
defer wg.Done()
if _, err := io.Copy(session, stdout); err != nil {
log.Error("Failed to write stdout to session. %s", err)
}
}()
go func() {
defer wg.Done()
if _, err := io.Copy(session.Stderr(), stderr); err != nil {
log.Error("Failed to write stderr to session. %s", err)
}
}()
// Ensure all the output has been written before we wait on the command
// to exit.
wg.Wait()
// Wait for the command to exit and log any errors we get
err = cmd.Wait()
if err != nil {
log.Error("SSH: Wait: %v", err)
}
if err := session.Exit(getExitStatusFromError(err)); err != nil {
log.Error("Session failed to exit. %s", err)
}
}
func publicKeyHandler(ctx ssh.Context, key ssh.PublicKey) bool {
if ctx.User() != setting.SSH.BuiltinServerUser {
return false
}
// Before use, a handshake must be performed on the incoming net.Conn.
// It must be handled in a separate goroutine,
// otherwise one user could easily block entire loop.
// For example, user could be asked to trust server key fingerprint and hangs.
go func() {
log.Trace("SSH: Handshaking for %s", conn.RemoteAddr())
sConn, chans, reqs, err := ssh.NewServerConn(conn, config)
if err != nil {
if err == io.EOF {
log.Warn("SSH: Handshaking with %s was terminated: %v", conn.RemoteAddr(), err)
} else {
log.Error("SSH: Error on handshaking with %s: %v", conn.RemoteAddr(), err)
}
return
}
log.Trace("SSH: Connection from %s (%s)", sConn.RemoteAddr(), sConn.ClientVersion())
// The incoming Request channel must be serviced.
go ssh.DiscardRequests(reqs)
go handleServerConn(sConn.Permissions.Extensions["key-id"], chans)
}()
pkey, err := models.SearchPublicKeyByContent(strings.TrimSpace(string(gossh.MarshalAuthorizedKey(key))))
if err != nil {
log.Error("SearchPublicKeyByContent: %v", err)
return false
}
ctx.SetValue(giteaKeyID, pkey.ID)
return true
}
// Listen starts a SSH server listens on given port.
func Listen(host string, port int, ciphers []string, keyExchanges []string, macs []string) {
config := &ssh.ServerConfig{
Config: ssh.Config{
Ciphers: ciphers,
KeyExchanges: keyExchanges,
MACs: macs,
},
PublicKeyCallback: func(conn ssh.ConnMetadata, key ssh.PublicKey) (*ssh.Permissions, error) {
pkey, err := models.SearchPublicKeyByContent(strings.TrimSpace(string(ssh.MarshalAuthorizedKey(key))))
if err != nil {
log.Error("SearchPublicKeyByContent: %v", err)
return nil, err
}
return &ssh.Permissions{Extensions: map[string]string{"key-id": com.ToStr(pkey.ID)}}, nil
// TODO: Handle ciphers, keyExchanges, and macs
srv := ssh.Server{
Addr: fmt.Sprintf("%s:%d", host, port),
PublicKeyHandler: publicKeyHandler,
Handler: sessionHandler,
// We need to explicitly disable the PtyCallback so text displays
// properly.
PtyCallback: func(ctx ssh.Context, pty ssh.Pty) bool {
return false
},
}
@ -197,20 +175,21 @@ func Listen(host string, port int, ciphers []string, keyExchanges []string, macs
if err != nil {
log.Fatal("Failed to generate private key: %v", err)
}
log.Trace("SSH: New private key is generateed: %s", keyPath)
log.Trace("New private key is generated: %s", keyPath)
}
privateBytes, err := ioutil.ReadFile(keyPath)
err := srv.SetOption(ssh.HostKeyFile(keyPath))
if err != nil {
log.Fatal("SSH: Failed to load private key")
log.Error("Failed to set Host Key. %s", err)
}
private, err := ssh.ParsePrivateKey(privateBytes)
if err != nil {
log.Fatal("SSH: Failed to parse private key")
}
config.AddHostKey(private)
go listen(config, host, port)
go func() {
err := srv.ListenAndServe()
if err != nil {
log.Error("Failed to serve with builtin SSH server. %s", err)
}
}()
}
// GenKeyPair make a pair of public and private keys for SSH access.
@ -238,12 +217,12 @@ func GenKeyPair(keyPath string) error {
}
// generate public key
pub, err := ssh.NewPublicKey(&privateKey.PublicKey)
pub, err := gossh.NewPublicKey(&privateKey.PublicKey)
if err != nil {
return err
}
public := ssh.MarshalAuthorizedKey(pub)
public := gossh.MarshalAuthorizedKey(pub)
p, err := os.OpenFile(keyPath+".pub", os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600)
if err != nil {
return err

@ -0,0 +1 @@
shlex.test

@ -0,0 +1,20 @@
Copyright (c) anmitsu <anmitsu.s@gmail.com>
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

@ -0,0 +1,38 @@
# go-shlex
go-shlex is a library to make a lexical analyzer like Unix shell for
Go.
## Install
go get -u "github.com/anmitsu/go-shlex"
## Usage
```go
package main
import (
"fmt"
"log"
"github.com/anmitsu/go-shlex"
)
func main() {
cmd := `cp -Rdp "file name" 'file name2' dir\ name`
words, err := shlex.Split(cmd, true)
if err != nil {
log.Fatal(err)
}
for _, w := range words {
fmt.Println(w)
}
}
```
## Documentation
http://godoc.org/github.com/anmitsu/go-shlex

@ -0,0 +1,193 @@
// Package shlex provides a simple lexical analysis like Unix shell.
package shlex
import (
"bufio"
"errors"
"io"
"strings"
"unicode"
)
var (
ErrNoClosing = errors.New("No closing quotation")
ErrNoEscaped = errors.New("No escaped character")
)
// Tokenizer is the interface that classifies a token according to
// words, whitespaces, quotations, escapes and escaped quotations.
type Tokenizer interface {
IsWord(rune) bool
IsWhitespace(rune) bool
IsQuote(rune) bool
IsEscape(rune) bool
IsEscapedQuote(rune) bool
}
// DefaultTokenizer implements a simple tokenizer like Unix shell.
type DefaultTokenizer struct{}
func (t *DefaultTokenizer) IsWord(r rune) bool {
return r == '_' || unicode.IsLetter(r) || unicode.IsNumber(r)
}
func (t *DefaultTokenizer) IsQuote(r rune) bool {
switch r {
case '\'', '"':
return true
default:
return false
}
}
func (t *DefaultTokenizer) IsWhitespace(r rune) bool {
return unicode.IsSpace(r)
}
func (t *DefaultTokenizer) IsEscape(r rune) bool {
return r == '\\'
}
func (t *DefaultTokenizer) IsEscapedQuote(r rune) bool {
return r == '"'
}
// Lexer represents a lexical analyzer.
type Lexer struct {
reader *bufio.Reader
tokenizer Tokenizer
posix bool
whitespacesplit bool
}
// NewLexer creates a new Lexer reading from io.Reader. This Lexer
// has a DefaultTokenizer according to posix and whitespacesplit
// rules.
func NewLexer(r io.Reader, posix, whitespacesplit bool) *Lexer {
return &Lexer{
reader: bufio.NewReader(r),
tokenizer: &DefaultTokenizer{},
posix: posix,
whitespacesplit: whitespacesplit,
}
}
// NewLexerString creates a new Lexer reading from a string. This
// Lexer has a DefaultTokenizer according to posix and whitespacesplit
// rules.
func NewLexerString(s string, posix, whitespacesplit bool) *Lexer {
return NewLexer(strings.NewReader(s), posix, whitespacesplit)
}
// Split splits a string according to posix or non-posix rules.
func Split(s string, posix bool) ([]string, error) {
return NewLexerString(s, posix, true).Split()
}
// SetTokenizer sets a Tokenizer.
func (l *Lexer) SetTokenizer(t Tokenizer) {
l.tokenizer = t
}
func (l *Lexer) Split() ([]string, error) {
result := make([]string, 0)
for {
token, err := l.readToken()
if token != "" {
result = append(result, token)
}
if err == io.EOF {
break
} else if err != nil {
return result, err
}
}
return result, nil
}
func (l *Lexer) readToken() (string, error) {
t := l.tokenizer
token := ""
quoted := false
state := ' '
escapedstate := ' '
scanning:
for {
next, _, err := l.reader.ReadRune()
if err != nil {
if t.IsQuote(state) {
return token, ErrNoClosing
} else if t.IsEscape(state) {
return token, ErrNoEscaped
}
return token, err
}
switch {
case t.IsWhitespace(state):
switch {
case t.IsWhitespace(next):
break scanning
case l.posix && t.IsEscape(next):
escapedstate = 'a'
state = next
case t.IsWord(next):
token += string(next)
state = 'a'
case t.IsQuote(next):
if !l.posix {
token += string(next)
}
state = next
default:
token = string(next)
if l.whitespacesplit {
state = 'a'
} else if token != "" || (l.posix && quoted) {
break scanning
}
}
case t.IsQuote(state):
quoted = true
switch {
case next == state:
if !l.posix {
token += string(next)
break scanning
} else {
state = 'a'
}
case l.posix && t.IsEscape(next) && t.IsEscapedQuote(state):
escapedstate = state
state = next
default:
token += string(next)
}
case t.IsEscape(state):
if t.IsQuote(escapedstate) && next != state && next != escapedstate {
token += string(state)
}
token += string(next)
state = escapedstate
case t.IsWord(state):
switch {
case t.IsWhitespace(next):
if token != "" || (l.posix && quoted) {
break scanning
}
case l.posix && t.IsQuote(next):
state = next
case l.posix && t.IsEscape(next):
escapedstate = 'a'
state = next
case t.IsWord(next) || t.IsQuote(next):
token += string(next)
default:
if l.whitespacesplit {
token += string(next)
} else if token != "" {
l.reader.UnreadRune()
break scanning
}
}
}
}
return token, nil
}

@ -0,0 +1,27 @@
Copyright (c) 2016 Glider Labs. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Glider Labs nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

@ -0,0 +1,96 @@
# gliderlabs/ssh
[![GoDoc](https://godoc.org/github.com/gliderlabs/ssh?status.svg)](https://godoc.org/github.com/gliderlabs/ssh)
[![CircleCI](https://img.shields.io/circleci/project/github/gliderlabs/ssh.svg)](https://circleci.com/gh/gliderlabs/ssh)
[![Go Report Card](https://goreportcard.com/badge/github.com/gliderlabs/ssh)](https://goreportcard.com/report/github.com/gliderlabs/ssh)
[![OpenCollective](https://opencollective.com/ssh/sponsors/badge.svg)](#sponsors)
[![Slack](http://slack.gliderlabs.com/badge.svg)](http://slack.gliderlabs.com)
[![Email Updates](https://img.shields.io/badge/updates-subscribe-yellow.svg)](https://app.convertkit.com/landing_pages/243312)
> The Glider Labs SSH server package is dope. &mdash;[@bradfitz](https://twitter.com/bradfitz), Go team member
This Go package wraps the [crypto/ssh
package](https://godoc.org/golang.org/x/crypto/ssh) with a higher-level API for
building SSH servers. The goal of the API was to make it as simple as using
[net/http](https://golang.org/pkg/net/http/), so the API is very similar:
```go
package main
import (
"github.com/gliderlabs/ssh"
"io"
"log"
)
func main() {
ssh.Handle(func(s ssh.Session) {
io.WriteString(s, "Hello world\n")
})
log.Fatal(ssh.ListenAndServe(":2222", nil))
}
```
This package was built by [@progrium](https://twitter.com/progrium) after working on nearly a dozen projects at Glider Labs using SSH and collaborating with [@shazow](https://twitter.com/shazow) (known for [ssh-chat](https://github.com/shazow/ssh-chat)).
## Examples
A bunch of great examples are in the `_examples` directory.
## Usage
[See GoDoc reference.](https://godoc.org/github.com/gliderlabs/ssh)
## Contributing
Pull requests are welcome! However, since this project is very much about API
design, please submit API changes as issues to discuss before submitting PRs.
Also, you can [join our Slack](http://slack.gliderlabs.com) to discuss as well.
## Roadmap
* Non-session channel handlers
* Cleanup callback API
* 1.0 release
* High-level client?
## Sponsors
Become a sponsor and get your logo on our README on Github with a link to your site. [[Become a sponsor](https://opencollective.com/ssh#sponsor)]
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## License
BSD

@ -0,0 +1,83 @@
package ssh
import (
"io"
"io/ioutil"
"net"
"path"
"sync"
gossh "golang.org/x/crypto/ssh"
)
const (
agentRequestType = "auth-agent-req@openssh.com"
agentChannelType = "auth-agent@openssh.com"
agentTempDir = "auth-agent"
agentListenFile = "listener.sock"
)
// contextKeyAgentRequest is an internal context key for storing if the
// client requested agent forwarding
var contextKeyAgentRequest = &contextKey{"auth-agent-req"}
// SetAgentRequested sets up the session context so that AgentRequested
// returns true.
func SetAgentRequested(ctx Context) {
ctx.SetValue(contextKeyAgentRequest, true)
}
// AgentRequested returns true if the client requested agent forwarding.
func AgentRequested(sess Session) bool {
return sess.Context().Value(contextKeyAgentRequest) == true
}
// NewAgentListener sets up a temporary Unix socket that can be communicated
// to the session environment and used for forwarding connections.
func NewAgentListener() (net.Listener, error) {
dir, err := ioutil.TempDir("", agentTempDir)
if err != nil {
return nil, err
}
l, err := net.Listen("unix", path.Join(dir, agentListenFile))
if err != nil {
return nil, err
}
return l, nil
}
// ForwardAgentConnections takes connections from a listener to proxy into the
// session on the OpenSSH channel for agent connections. It blocks and services
// connections until the listener stop accepting.
func ForwardAgentConnections(l net.Listener, s Session) {
sshConn := s.Context().Value(ContextKeyConn).(gossh.Conn)
for {
conn, err := l.Accept()
if err != nil {
return
}
go func(conn net.Conn) {
defer conn.Close()
channel, reqs, err := sshConn.OpenChannel(agentChannelType, nil)
if err != nil {
return
}
defer channel.Close()
go gossh.DiscardRequests(reqs)
var wg sync.WaitGroup
wg.Add(2)
go func() {
io.Copy(conn, channel)
conn.(*net.UnixConn).CloseWrite()
wg.Done()
}()
go func() {
io.Copy(channel, conn)
channel.CloseWrite()
wg.Done()
}()
wg.Wait()
}(conn)
}
}

@ -0,0 +1,26 @@
version: 2
jobs:
build-go-latest:
docker:
- image: golang:latest
working_directory: /go/src/github.com/gliderlabs/ssh
steps:
- checkout
- run: go get
- run: go test -v -race
build-go-1.9:
docker:
- image: golang:1.9
working_directory: /go/src/github.com/gliderlabs/ssh
steps:
- checkout
- run: go get
- run: go test -v -race
workflows:
version: 2
build:
jobs:
- build-go-latest
- build-go-1.9

@ -0,0 +1,55 @@
package ssh
import (
"context"
"net"
"time"
)
type serverConn struct {
net.Conn
idleTimeout time.Duration
maxDeadline time.Time
closeCanceler context.CancelFunc
}
func (c *serverConn) Write(p []byte) (n int, err error) {
c.updateDeadline()
n, err = c.Conn.Write(p)
if _, isNetErr := err.(net.Error); isNetErr && c.closeCanceler != nil {
c.closeCanceler()
}
return
}
func (c *serverConn) Read(b []byte) (n int, err error) {
c.updateDeadline()
n, err = c.Conn.Read(b)
if _, isNetErr := err.(net.Error); isNetErr && c.closeCanceler != nil {
c.closeCanceler()
}
return
}
func (c *serverConn) Close() (err error) {
err = c.Conn.Close()
if c.closeCanceler != nil {
c.closeCanceler()
}
return
}
func (c *serverConn) updateDeadline() {
switch {
case c.idleTimeout > 0:
idleDeadline := time.Now().Add(c.idleTimeout)
if idleDeadline.Unix() < c.maxDeadline.Unix() || c.maxDeadline.IsZero() {
c.Conn.SetDeadline(idleDeadline)
return
}
fallthrough
default:
c.Conn.SetDeadline(c.maxDeadline)
}
}

@ -0,0 +1,152 @@
package ssh
import (
"context"
"encoding/hex"
"net"
"sync"
gossh "golang.org/x/crypto/ssh"
)
// contextKey is a value for use with context.WithValue. It's used as
// a pointer so it fits in an interface{} without allocation.
type contextKey struct {
name string
}
var (
// ContextKeyUser is a context key for use with Contexts in this package.
// The associated value will be of type string.
ContextKeyUser = &contextKey{"user"}
// ContextKeySessionID is a context key for use with Contexts in this package.
// The associated value will be of type string.
ContextKeySessionID = &contextKey{"session-id"}
// ContextKeyPermissions is a context key for use with Contexts in this package.
// The associated value will be of type *Permissions.
ContextKeyPermissions = &contextKey{"permissions"}
// ContextKeyClientVersion is a context key for use with Contexts in this package.
// The associated value will be of type string.
ContextKeyClientVersion = &contextKey{"client-version"}
// ContextKeyServerVersion is a context key for use with Contexts in this package.
// The associated value will be of type string.
ContextKeyServerVersion = &contextKey{"server-version"}
// ContextKeyLocalAddr is a context key for use with Contexts in this package.
// The associated value will be of type net.Addr.
ContextKeyLocalAddr = &contextKey{"local-addr"}
// ContextKeyRemoteAddr is a context key for use with Contexts in this package.
// The associated value will be of type net.Addr.
ContextKeyRemoteAddr = &contextKey{"remote-addr"}
// ContextKeyServer is a context key for use with Contexts in this package.
// The associated value will be of type *Server.
ContextKeyServer = &contextKey{"ssh-server"}
// ContextKeyConn is a context key for use with Contexts in this package.
// The associated value will be of type gossh.ServerConn.
ContextKeyConn = &contextKey{"ssh-conn"}
// ContextKeyPublicKey is a context key for use with Contexts in this package.
// The associated value will be of type PublicKey.
ContextKeyPublicKey = &contextKey{"public-key"}
)
// Context is a package specific context interface. It exposes connection
// metadata and allows new values to be easily written to it. It's used in
// authentication handlers and callbacks, and its underlying context.Context is
// exposed on Session in the session Handler. A connection-scoped lock is also
// embedded in the context to make it easier to limit operations per-connection.
type Context interface {
context.Context
sync.Locker
// User returns the username used when establishing the SSH connection.
User() string
// SessionID returns the session hash.
SessionID() string
// ClientVersion returns the version reported by the client.
ClientVersion() string
// ServerVersion returns the version reported by the server.
ServerVersion() string
// RemoteAddr returns the remote address for this connection.
RemoteAddr() net.Addr
// LocalAddr returns the local address for this connection.
LocalAddr() net.Addr
// Permissions returns the Permissions object used for this connection.
Permissions() *Permissions
// SetValue allows you to easily write new values into the underlying context.
SetValue(key, value interface{})
}
type sshContext struct {
context.Context
*sync.Mutex
}
func newContext(srv *Server) (*sshContext, context.CancelFunc) {
innerCtx, cancel := context.WithCancel(context.Background())
ctx := &sshContext{innerCtx, &sync.Mutex{}}
ctx.SetValue(ContextKeyServer, srv)
perms := &Permissions{&gossh.Permissions{}}
ctx.SetValue(ContextKeyPermissions, perms)
return ctx, cancel
}
// this is separate from newContext because we will get ConnMetadata
// at different points so it needs to be applied separately
func applyConnMetadata(ctx Context, conn gossh.ConnMetadata) {
if ctx.Value(ContextKeySessionID) != nil {
return
}
ctx.SetValue(ContextKeySessionID, hex.EncodeToString(conn.SessionID()))
ctx.SetValue(ContextKeyClientVersion, string(conn.ClientVersion()))
ctx.SetValue(ContextKeyServerVersion, string(conn.ServerVersion()))
ctx.SetValue(ContextKeyUser, conn.User())
ctx.SetValue(ContextKeyLocalAddr, conn.LocalAddr())
ctx.SetValue(ContextKeyRemoteAddr, conn.RemoteAddr())
}
func (ctx *sshContext) SetValue(key, value interface{}) {
ctx.Context = context.WithValue(ctx.Context, key, value)
}
func (ctx *sshContext) User() string {
return ctx.Value(ContextKeyUser).(string)
}
func (ctx *sshContext) SessionID() string {
return ctx.Value(ContextKeySessionID).(string)
}
func (ctx *sshContext) ClientVersion() string {
return ctx.Value(ContextKeyClientVersion).(string)
}
func (ctx *sshContext) ServerVersion() string {
return ctx.Value(ContextKeyServerVersion).(string)
}
func (ctx *sshContext) RemoteAddr() net.Addr {
return ctx.Value(ContextKeyRemoteAddr).(net.Addr)
}
func (ctx *sshContext) LocalAddr() net.Addr {
return ctx.Value(ContextKeyLocalAddr).(net.Addr)
}
func (ctx *sshContext) Permissions() *Permissions {
return ctx.Value(ContextKeyPermissions).(*Permissions)
}

@ -0,0 +1,45 @@
/*
Package ssh wraps the crypto/ssh package with a higher-level API for building
SSH servers. The goal of the API was to make it as simple as using net/http, so
the API is very similar.
You should be able to build any SSH server using only this package, which wraps
relevant types and some functions from crypto/ssh. However, you still need to
use crypto/ssh for building SSH clients.
ListenAndServe starts an SSH server with a given address, handler, and options. The
handler is usually nil, which means to use DefaultHandler. Handle sets DefaultHandler:
ssh.Handle(func(s ssh.Session) {
io.WriteString(s, "Hello world\n")
})
log.Fatal(ssh.ListenAndServe(":2222", nil))
If you don't specify a host key, it will generate one every time. This is convenient
except you'll have to deal with clients being confused that the host key is different.
It's a better idea to generate or point to an existing key on your system:
log.Fatal(ssh.ListenAndServe(":2222", nil, ssh.HostKeyFile("/Users/progrium/.ssh/id_rsa")))
Although all options have functional option helpers, another way to control the
server's behavior is by creating a custom Server:
s := &ssh.Server{
Addr: ":2222",
Handler: sessionHandler,
PublicKeyHandler: authHandler,
}
s.AddHostKey(hostKeySigner)
log.Fatal(s.ListenAndServe())
This package automatically handles basic SSH requests like setting environment
variables, requesting PTY, and changing window size. These requests are
processed, responded to, and any relevant state is updated. This state is then
exposed to you via the Session interface.
The one big feature missing from the Session abstraction is signals. This was
started, but not completed. Pull Requests welcome!
*/
package ssh

@ -0,0 +1,77 @@
package ssh
import (
"io/ioutil"
gossh "golang.org/x/crypto/ssh"
)
// PasswordAuth returns a functional option that sets PasswordHandler on the server.
func PasswordAuth(fn PasswordHandler) Option {
return func(srv *Server) error {
srv.PasswordHandler = fn
return nil
}
}
// PublicKeyAuth returns a functional option that sets PublicKeyHandler on the server.
func PublicKeyAuth(fn PublicKeyHandler) Option {
return func(srv *Server) error {
srv.PublicKeyHandler = fn
return nil
}
}
// HostKeyFile returns a functional option that adds HostSigners to the server
// from a PEM file at filepath.
func HostKeyFile(filepath string) Option {
return func(srv *Server) error {
pemBytes, err := ioutil.ReadFile(filepath)
if err != nil {
return err
}
signer, err := gossh.ParsePrivateKey(pemBytes)
if err != nil {
return err
}
srv.AddHostKey(signer)
return nil
}
}
// HostKeyPEM returns a functional option that adds HostSigners to the server
// from a PEM file as bytes.
func HostKeyPEM(bytes []byte) Option {
return func(srv *Server) error {
signer, err := gossh.ParsePrivateKey(bytes)
if err != nil {
return err
}
srv.AddHostKey(signer)
return nil
}
}
// NoPty returns a functional option that sets PtyCallback to return false,
// denying PTY requests.
func NoPty() Option {
return func(srv *Server) error {
srv.PtyCallback = func(ctx Context, pty Pty) bool {
return false
}
return nil
}
}
// WrapConn returns a functional option that sets ConnCallback on the server.
func WrapConn(fn ConnCallback) Option {
return func(srv *Server) error {
srv.ConnCallback = fn
return nil
}
}

@ -0,0 +1,394 @@
package ssh
import (
"context"
"errors"
"fmt"
"net"
"sync"
"time"
gossh "golang.org/x/crypto/ssh"
)
// ErrServerClosed is returned by the Server's Serve, ListenAndServe,
// and ListenAndServeTLS methods after a call to Shutdown or Close.
var ErrServerClosed = errors.New("ssh: Server closed")
type RequestHandler func(ctx Context, srv *Server, req *gossh.Request) (ok bool, payload []byte)
var DefaultRequestHandlers = map[string]RequestHandler{}
type ChannelHandler func(srv *Server, conn *gossh.ServerConn, newChan gossh.NewChannel, ctx Context)
var DefaultChannelHandlers = map[string]ChannelHandler{
"session": DefaultSessionHandler,
}
// Server defines parameters for running an SSH server. The zero value for
// Server is a valid configuration. When both PasswordHandler and
// PublicKeyHandler are nil, no client authentication is performed.
type Server struct {
Addr string // TCP address to listen on, ":22" if empty
Handler Handler // handler to invoke, ssh.DefaultHandler if nil
HostSigners []Signer // private keys for the host key, must have at least one
Version string // server version to be sent before the initial handshake
KeyboardInteractiveHandler KeyboardInteractiveHandler // keyboard-interactive authentication handler
PasswordHandler PasswordHandler // password authentication handler
PublicKeyHandler PublicKeyHandler // public key authentication handler
PtyCallback PtyCallback // callback for allowing PTY sessions, allows all if nil
ConnCallback ConnCallback // optional callback for wrapping net.Conn before handling
LocalPortForwardingCallback LocalPortForwardingCallback // callback for allowing local port forwarding, denies all if nil
ReversePortForwardingCallback ReversePortForwardingCallback // callback for allowing reverse port forwarding, denies all if nil
ServerConfigCallback ServerConfigCallback // callback for configuring detailed SSH options
SessionRequestCallback SessionRequestCallback // callback for allowing or denying SSH sessions
IdleTimeout time.Duration // connection timeout when no activity, none if empty
MaxTimeout time.Duration // absolute connection timeout, none if empty
// ChannelHandlers allow overriding the built-in session handlers or provide
// extensions to the protocol, such as tcpip forwarding. By default only the
// "session" handler is enabled.
ChannelHandlers map[string]ChannelHandler
// RequestHandlers allow overriding the server-level request handlers or
// provide extensions to the protocol, such as tcpip forwarding. By default
// no handlers are enabled.
RequestHandlers map[string]RequestHandler
listenerWg sync.WaitGroup
mu sync.Mutex
listeners map[net.Listener]struct{}
conns map[*gossh.ServerConn]struct{}
connWg sync.WaitGroup
doneChan chan struct{}
}
func (srv *Server) ensureHostSigner() error {
if len(srv.HostSigners) == 0 {
signer, err := generateSigner()
if err != nil {
return err
}
srv.HostSigners = append(srv.HostSigners, signer)
}
return nil
}
func (srv *Server) ensureHandlers() {
srv.mu.Lock()
defer srv.mu.Unlock()
if srv.RequestHandlers == nil {
srv.RequestHandlers = map[string]RequestHandler{}
for k, v := range DefaultRequestHandlers {
srv.RequestHandlers[k] = v
}
}
if srv.ChannelHandlers == nil {
srv.ChannelHandlers = map[string]ChannelHandler{}
for k, v := range DefaultChannelHandlers {
srv.ChannelHandlers[k] = v
}
}
}
func (srv *Server) config(ctx Context) *gossh.ServerConfig {
var config *gossh.ServerConfig
if srv.ServerConfigCallback == nil {
config = &gossh.ServerConfig{}
} else {
config = srv.ServerConfigCallback(ctx)
}
for _, signer := range srv.HostSigners {
config.AddHostKey(signer)
}
if srv.PasswordHandler == nil && srv.PublicKeyHandler == nil {
config.NoClientAuth = true
}
if srv.Version != "" {
config.ServerVersion = "SSH-2.0-" + srv.Version
}
if srv.PasswordHandler != nil {
config.PasswordCallback = func(conn gossh.ConnMetadata, password []byte) (*gossh.Permissions, error) {
applyConnMetadata(ctx, conn)
if ok := srv.PasswordHandler(ctx, string(password)); !ok {
return ctx.Permissions().Permissions, fmt.Errorf("permission denied")
}
return ctx.Permissions().Permissions, nil
}
}
if srv.PublicKeyHandler != nil {
config.PublicKeyCallback = func(conn gossh.ConnMetadata, key gossh.PublicKey) (*gossh.Permissions, error) {
applyConnMetadata(ctx, conn)
if ok := srv.PublicKeyHandler(ctx, key); !ok {
return ctx.Permissions().Permissions, fmt.Errorf("permission denied")
}
ctx.SetValue(ContextKeyPublicKey, key)
return ctx.Permissions().Permissions, nil
}
}
if srv.KeyboardInteractiveHandler != nil {
config.KeyboardInteractiveCallback = func(conn gossh.ConnMetadata, challenger gossh.KeyboardInteractiveChallenge) (*gossh.Permissions, error) {
if ok := srv.KeyboardInteractiveHandler(ctx, challenger); !ok {
return ctx.Permissions().Permissions, fmt.Errorf("permission denied")
}
return ctx.Permissions().Permissions, nil
}
}
return config
}
// Handle sets the Handler for the server.
func (srv *Server) Handle(fn Handler) {
srv.Handler = fn
}
// Close immediately closes all active listeners and all active
// connections.
//
// Close returns any error returned from closing the Server's
// underlying Listener(s).
func (srv *Server) Close() error {
srv.mu.Lock()
defer srv.mu.Unlock()
srv.closeDoneChanLocked()
err := srv.closeListenersLocked()
for c := range srv.conns {
c.Close()
delete(srv.conns, c)
}
return err
}
// Shutdown gracefully shuts down the server without interrupting any
// active connections. Shutdown works by first closing all open
// listeners, and then waiting indefinitely for connections to close.
// If the provided context expires before the shutdown is complete,
// then the context's error is returned.
func (srv *Server) Shutdown(ctx context.Context) error {
srv.mu.Lock()
lnerr := srv.closeListenersLocked()
srv.closeDoneChanLocked()
srv.mu.Unlock()
finished := make(chan struct{}, 1)
go func() {
srv.listenerWg.Wait()
srv.connWg.Wait()
finished <- struct{}{}
}()
select {
case <-ctx.Done():
return ctx.Err()
case <-finished:
return lnerr
}
}
// Serve accepts incoming connections on the Listener l, creating a new
// connection goroutine for each. The connection goroutines read requests and then
// calls srv.Handler to handle sessions.
//
// Serve always returns a non-nil error.
func (srv *Server) Serve(l net.Listener) error {
srv.ensureHandlers()
defer l.Close()
if err := srv.ensureHostSigner(); err != nil {
return err
}
if srv.Handler == nil {
srv.Handler = DefaultHandler
}
var tempDelay time.Duration
srv.trackListener(l, true)
defer srv.trackListener(l, false)
for {
conn, e := l.Accept()
if e != nil {
select {
case <-srv.getDoneChan():
return ErrServerClosed
default:
}
if ne, ok := e.(net.Error); ok && ne.Temporary() {
if tempDelay == 0 {
tempDelay = 5 * time.Millisecond
} else {
tempDelay *= 2
}
if max := 1 * time.Second; tempDelay > max {
tempDelay = max
}
time.Sleep(tempDelay)
continue
}
return e
}
go srv.handleConn(conn)
}
}
func (srv *Server) handleConn(newConn net.Conn) {
if srv.ConnCallback != nil {
cbConn := srv.ConnCallback(newConn)
if cbConn == nil {
newConn.Close()
return
}
newConn = cbConn
}
ctx, cancel := newContext(srv)
conn := &serverConn{
Conn: newConn,
idleTimeout: srv.IdleTimeout,
closeCanceler: cancel,
}
if srv.MaxTimeout > 0 {
conn.maxDeadline = time.Now().Add(srv.MaxTimeout)
}
defer conn.Close()
sshConn, chans, reqs, err := gossh.NewServerConn(conn, srv.config(ctx))
if err != nil {
// TODO: trigger event callback
return
}
srv.trackConn(sshConn, true)
defer srv.trackConn(sshConn, false)
ctx.SetValue(ContextKeyConn, sshConn)
applyConnMetadata(ctx, sshConn)
//go gossh.DiscardRequests(reqs)
go srv.handleRequests(ctx, reqs)
for ch := range chans {
handler := srv.ChannelHandlers[ch.ChannelType()]
if handler == nil {
handler = srv.ChannelHandlers["default"]
}
if handler == nil {
ch.Reject(gossh.UnknownChannelType, "unsupported channel type")
continue
}
go handler(srv, sshConn, ch, ctx)
}
}
func (srv *Server) handleRequests(ctx Context, in <-chan *gossh.Request) {
for req := range in {
handler := srv.RequestHandlers[req.Type]
if handler == nil {
handler = srv.RequestHandlers["default"]
}
if handler == nil {
req.Reply(false, nil)
continue
}
/*reqCtx, cancel := context.WithCancel(ctx)
defer cancel() */
ret, payload := handler(ctx, srv, req)
req.Reply(ret, payload)
}
}
// ListenAndServe listens on the TCP network address srv.Addr and then calls
// Serve to handle incoming connections. If srv.Addr is blank, ":22" is used.
// ListenAndServe always returns a non-nil error.
func (srv *Server) ListenAndServe() error {
addr := srv.Addr
if addr == "" {
addr = ":22"
}
ln, err := net.Listen("tcp", addr)
if err != nil {
return err
}
return srv.Serve(ln)
}
// AddHostKey adds a private key as a host key. If an existing host key exists
// with the same algorithm, it is overwritten. Each server config must have at
// least one host key.
func (srv *Server) AddHostKey(key Signer) {
// these are later added via AddHostKey on ServerConfig, which performs the
// check for one of every algorithm.
srv.HostSigners = append(srv.HostSigners, key)
}
// SetOption runs a functional option against the server.
func (srv *Server) SetOption(option Option) error {
return option(srv)
}
func (srv *Server) getDoneChan() <-chan struct{} {
srv.mu.Lock()
defer srv.mu.Unlock()
return srv.getDoneChanLocked()
}
func (srv *Server) getDoneChanLocked() chan struct{} {
if srv.doneChan == nil {
srv.doneChan = make(chan struct{})
}
return srv.doneChan
}
func (srv *Server) closeDoneChanLocked() {
ch := srv.getDoneChanLocked()
select {
case <-ch:
// Already closed. Don't close again.
default:
// Safe to close here. We're the only closer, guarded
// by srv.mu.
close(ch)
}
}
func (srv *Server) closeListenersLocked() error {
var err error
for ln := range srv.listeners {
if cerr := ln.Close(); cerr != nil && err == nil {
err = cerr
}
delete(srv.listeners, ln)
}
return err
}
func (srv *Server) trackListener(ln net.Listener, add bool) {
srv.mu.Lock()
defer srv.mu.Unlock()
if srv.listeners == nil {
srv.listeners = make(map[net.Listener]struct{})
}
if add {
// If the *Server is being reused after a previous
// Close or Shutdown, reset its doneChan:
if len(srv.listeners) == 0 && len(srv.conns) == 0 {
srv.doneChan = nil
}
srv.listeners[ln] = struct{}{}
srv.listenerWg.Add(1)
} else {
delete(srv.listeners, ln)
srv.listenerWg.Done()
}
}
func (srv *Server) trackConn(c *gossh.ServerConn, add bool) {
srv.mu.Lock()
defer srv.mu.Unlock()
if srv.conns == nil {
srv.conns = make(map[*gossh.ServerConn]struct{})
}
if add {
srv.conns[c] = struct{}{}
srv.connWg.Add(1)
} else {
delete(srv.conns, c)
srv.connWg.Done()
}
}

@ -0,0 +1,308 @@
package ssh
import (
"bytes"
"context"
"errors"
"fmt"
"net"
"sync"
"github.com/anmitsu/go-shlex"
gossh "golang.org/x/crypto/ssh"
)
// Session provides access to information about an SSH session and methods
// to read and write to the SSH channel with an embedded Channel interface from
// cypto/ssh.
//
// When Command() returns an empty slice, the user requested a shell. Otherwise
// the user is performing an exec with those command arguments.
//
// TODO: Signals
type Session interface {
gossh.Channel
// User returns the username used when establishing the SSH connection.
User() string
// RemoteAddr returns the net.Addr of the client side of the connection.
RemoteAddr() net.Addr
// LocalAddr returns the net.Addr of the server side of the connection.
LocalAddr() net.Addr
// Environ returns a copy of strings representing the environment set by the
// user for this session, in the form "key=value".
Environ() []string
// Exit sends an exit status and then closes the session.
Exit(code int) error
// Command returns a shell parsed slice of arguments that were provided by the
// user. Shell parsing splits the command string according to POSIX shell rules,
// which considers quoting not just whitespace.
Command() []string
// RawCommand returns the exact command that was provided by the user.
RawCommand() string
// PublicKey returns the PublicKey used to authenticate. If a public key was not
// used it will return nil.
PublicKey() PublicKey
// Context returns the connection's context. The returned context is always
// non-nil and holds the same data as the Context passed into auth
// handlers and callbacks.
//
// The context is canceled when the client's connection closes or I/O
// operation fails.
Context() context.Context
// Permissions returns a copy of the Permissions object that was available for
// setup in the auth handlers via the Context.
Permissions() Permissions
// Pty returns PTY information, a channel of window size changes, and a boolean
// of whether or not a PTY was accepted for this session.
Pty() (Pty, <-chan Window, bool)
// Signals registers a channel to receive signals sent from the client. The
// channel must handle signal sends or it will block the SSH request loop.
// Registering nil will unregister the channel from signal sends. During the
// time no channel is registered signals are buffered up to a reasonable amount.
// If there are buffered signals when a channel is registered, they will be
// sent in order on the channel immediately after registering.
Signals(c chan<- Signal)
}
// maxSigBufSize is how many signals will be buffered
// when there is no signal channel specified
const maxSigBufSize = 128
func DefaultSessionHandler(srv *Server, conn *gossh.ServerConn, newChan gossh.NewChannel, ctx Context) {
ch, reqs, err := newChan.Accept()
if err != nil {
// TODO: trigger event callback
return
}
sess := &session{
Channel: ch,
conn: conn,
handler: srv.Handler,
ptyCb: srv.PtyCallback,
sessReqCb: srv.SessionRequestCallback,
ctx: ctx,
}
sess.handleRequests(reqs)
}
type session struct {
sync.Mutex
gossh.Channel
conn *gossh.ServerConn
handler Handler
handled bool
exited bool
pty *Pty
winch chan Window
env []string
ptyCb PtyCallback
sessReqCb SessionRequestCallback
rawCmd string
ctx Context
sigCh chan<- Signal
sigBuf []Signal
}
func (sess *session) Write(p []byte) (n int, err error) {
if sess.pty != nil {
m := len(p)
// normalize \n to \r\n when pty is accepted.
// this is a hardcoded shortcut since we don't support terminal modes.
p = bytes.Replace(p, []byte{'\n'}, []byte{'\r', '\n'}, -1)
p = bytes.Replace(p, []byte{'\r', '\r', '\n'}, []byte{'\r', '\n'}, -1)
n, err = sess.Channel.Write(p)
if n > m {
n = m
}
return
}
return sess.Channel.Write(p)
}
func (sess *session) PublicKey() PublicKey {
sessionkey := sess.ctx.Value(ContextKeyPublicKey)
if sessionkey == nil {
return nil
}
return sessionkey.(PublicKey)
}
func (sess *session) Permissions() Permissions {
// use context permissions because its properly
// wrapped and easier to dereference
perms := sess.ctx.Value(ContextKeyPermissions).(*Permissions)
return *perms
}
func (sess *session) Context() context.Context {
return sess.ctx
}
func (sess *session) Exit(code int) error {
sess.Lock()
defer sess.Unlock()
if sess.exited {
return errors.New("Session.Exit called multiple times")
}
sess.exited = true
status := struct{ Status uint32 }{uint32(code)}
_, err := sess.SendRequest("exit-status", false, gossh.Marshal(&status))
if err != nil {
return err
}
return sess.Close()
}
func (sess *session) User() string {
return sess.conn.User()
}
func (sess *session) RemoteAddr() net.Addr {
return sess.conn.RemoteAddr()
}
func (sess *session) LocalAddr() net.Addr {
return sess.conn.LocalAddr()
}
func (sess *session) Environ() []string {
return append([]string(nil), sess.env...)
}
func (sess *session) RawCommand() string {
return sess.rawCmd
}
func (sess *session) Command() []string {
cmd, _ := shlex.Split(sess.rawCmd, true)
return append([]string(nil), cmd...)
}
func (sess *session) Pty() (Pty, <-chan Window, bool) {
if sess.pty != nil {
return *sess.pty, sess.winch, true
}
return Pty{}, sess.winch, false
}
func (sess *session) Signals(c chan<- Signal) {
sess.Lock()
defer sess.Unlock()
sess.sigCh = c
if len(sess.sigBuf) > 0 {
go func() {
for _, sig := range sess.sigBuf {
sess.sigCh <- sig
}
}()
}
}
func (sess *session) handleRequests(reqs <-chan *gossh.Request) {
for req := range reqs {
switch req.Type {
case "shell", "exec":
if sess.handled {
req.Reply(false, nil)
continue
}
var payload = struct{ Value string }{}
gossh.Unmarshal(req.Payload, &payload)
sess.rawCmd = payload.Value
// If there's a session policy callback, we need to confirm before
// accepting the session.
if sess.sessReqCb != nil && !sess.sessReqCb(sess, req.Type) {
sess.rawCmd = ""
req.Reply(false, nil)
continue
}
sess.handled = true
req.Reply(true, nil)
go func() {
sess.handler(sess)
sess.Exit(0)
}()
case "env":
if sess.handled {
req.Reply(false, nil)
continue
}
var kv struct{ Key, Value string }
gossh.Unmarshal(req.Payload, &kv)
sess.env = append(sess.env, fmt.Sprintf("%s=%s", kv.Key, kv.Value))
req.Reply(true, nil)
case "signal":
var payload struct{ Signal string }
gossh.Unmarshal(req.Payload, &payload)
sess.Lock()
if sess.sigCh != nil {
sess.sigCh <- Signal(payload.Signal)
} else {
if len(sess.sigBuf) < maxSigBufSize {
sess.sigBuf = append(sess.sigBuf, Signal(payload.Signal))
}
}
sess.Unlock()
case "pty-req":
if sess.handled || sess.pty != nil {
req.Reply(false, nil)
continue
}
ptyReq, ok := parsePtyRequest(req.Payload)
if !ok {
req.Reply(false, nil)
continue
}
if sess.ptyCb != nil {
ok := sess.ptyCb(sess.ctx, ptyReq)
if !ok {
req.Reply(false, nil)
continue
}
}
sess.pty = &ptyReq
sess.winch = make(chan Window, 1)
sess.winch <- ptyReq.Window
defer func() {
// when reqs is closed
close(sess.winch)
}()
req.Reply(ok, nil)
case "window-change":
if sess.pty == nil {
req.Reply(false, nil)
continue
}
win, ok := parseWinchRequest(req.Payload)
if ok {
sess.pty.Window = win
sess.winch <- win
}
req.Reply(ok, nil)
case agentRequestType:
// TODO: option/callback to allow agent forwarding
SetAgentRequested(sess.ctx)
req.Reply(true, nil)
default:
// TODO: debug log
req.Reply(false, nil)
}
}
}

@ -0,0 +1,123 @@
package ssh
import (
"crypto/subtle"
"net"
gossh "golang.org/x/crypto/ssh"
)
type Signal string
// POSIX signals as listed in RFC 4254 Section 6.10.
const (
SIGABRT Signal = "ABRT"
SIGALRM Signal = "ALRM"
SIGFPE Signal = "FPE"
SIGHUP Signal = "HUP"
SIGILL Signal = "ILL"
SIGINT Signal = "INT"
SIGKILL Signal = "KILL"
SIGPIPE Signal = "PIPE"
SIGQUIT Signal = "QUIT"
SIGSEGV Signal = "SEGV"
SIGTERM Signal = "TERM"
SIGUSR1 Signal = "USR1"
SIGUSR2 Signal = "USR2"
)
// DefaultHandler is the default Handler used by Serve.
var DefaultHandler Handler
// Option is a functional option handler for Server.
type Option func(*Server) error
// Handler is a callback for handling established SSH sessions.
type Handler func(Session)
// PublicKeyHandler is a callback for performing public key authentication.
type PublicKeyHandler func(ctx Context, key PublicKey) bool
// PasswordHandler is a callback for performing password authentication.
type PasswordHandler func(ctx Context, password string) bool
// KeyboardInteractiveHandler is a callback for performing keyboard-interactive authentication.
type KeyboardInteractiveHandler func(ctx Context, challenger gossh.KeyboardInteractiveChallenge) bool
// PtyCallback is a hook for allowing PTY sessions.
type PtyCallback func(ctx Context, pty Pty) bool
// SessionRequestCallback is a callback for allowing or denying SSH sessions.
type SessionRequestCallback func(sess Session, requestType string) bool
// ConnCallback is a hook for new connections before handling.
// It allows wrapping for timeouts and limiting by returning
// the net.Conn that will be used as the underlying connection.
type ConnCallback func(conn net.Conn) net.Conn
// LocalPortForwardingCallback is a hook for allowing port forwarding
type LocalPortForwardingCallback func(ctx Context, destinationHost string, destinationPort uint32) bool
// ReversePortForwardingCallback is a hook for allowing reverse port forwarding
type ReversePortForwardingCallback func(ctx Context, bindHost string, bindPort uint32) bool
// ServerConfigCallback is a hook for creating custom default server configs
type ServerConfigCallback func(ctx Context) *gossh.ServerConfig
// Window represents the size of a PTY window.
type Window struct {
Width int
Height int
}
// Pty represents a PTY request and configuration.
type Pty struct {
Term string
Window Window
// HELP WANTED: terminal modes!
}
// Serve accepts incoming SSH connections on the listener l, creating a new
// connection goroutine for each. The connection goroutines read requests and
// then calls handler to handle sessions. Handler is typically nil, in which
// case the DefaultHandler is used.
func Serve(l net.Listener, handler Handler, options ...Option) error {
srv := &Server{Handler: handler}
for _, option := range options {
if err := srv.SetOption(option); err != nil {
return err
}
}
return srv.Serve(l)
}
// ListenAndServe listens on the TCP network address addr and then calls Serve
// with handler to handle sessions on incoming connections. Handler is typically
// nil, in which case the DefaultHandler is used.
func ListenAndServe(addr string, handler Handler, options ...Option) error {
srv := &Server{Addr: addr, Handler: handler}
for _, option := range options {
if err := srv.SetOption(option); err != nil {
return err
}
}
return srv.ListenAndServe()
}
// Handle registers the handler as the DefaultHandler.
func Handle(handler Handler) {
DefaultHandler = handler
}
// KeysEqual is constant time compare of the keys to avoid timing attacks.
func KeysEqual(ak, bk PublicKey) bool {
//avoid panic if one of the keys is nil, return false instead
if ak == nil || bk == nil {
return false
}
a := ak.Marshal()
b := bk.Marshal()
return (len(a) == len(b) && subtle.ConstantTimeCompare(a, b) == 1)
}

@ -0,0 +1,193 @@
package ssh
import (
"io"
"log"
"net"
"strconv"
"sync"
gossh "golang.org/x/crypto/ssh"
)
const (
forwardedTCPChannelType = "forwarded-tcpip"
)
// direct-tcpip data struct as specified in RFC4254, Section 7.2
type localForwardChannelData struct {
DestAddr string
DestPort uint32
OriginAddr string
OriginPort uint32
}
// DirectTCPIPHandler can be enabled by adding it to the server's
// ChannelHandlers under direct-tcpip.
func DirectTCPIPHandler(srv *Server, conn *gossh.ServerConn, newChan gossh.NewChannel, ctx Context) {
d := localForwardChannelData{}
if err := gossh.Unmarshal(newChan.ExtraData(), &d); err != nil {
newChan.Reject(gossh.ConnectionFailed, "error parsing forward data: "+err.Error())
return
}
if srv.LocalPortForwardingCallback == nil || !srv.LocalPortForwardingCallback(ctx, d.DestAddr, d.DestPort) {
newChan.Reject(gossh.Prohibited, "port forwarding is disabled")
return
}
dest := net.JoinHostPort(d.DestAddr, strconv.FormatInt(int64(d.DestPort), 10))
var dialer net.Dialer
dconn, err := dialer.DialContext(ctx, "tcp", dest)
if err != nil {
newChan.Reject(gossh.ConnectionFailed, err.Error())
return
}
ch, reqs, err := newChan.Accept()
if err != nil {
dconn.Close()
return
}
go gossh.DiscardRequests(reqs)
go func() {
defer ch.Close()
defer dconn.Close()
io.Copy(ch, dconn)
}()
go func() {
defer ch.Close()
defer dconn.Close()
io.Copy(dconn, ch)
}()
}
type remoteForwardRequest struct {
BindAddr string
BindPort uint32
}
type remoteForwardSuccess struct {
BindPort uint32
}
type remoteForwardCancelRequest struct {
BindAddr string
BindPort uint32
}
type remoteForwardChannelData struct {
DestAddr string
DestPort uint32
OriginAddr string
OriginPort uint32
}
// ForwardedTCPHandler can be enabled by creating a ForwardedTCPHandler and
// adding the HandleSSHRequest callback to the server's RequestHandlers under
// tcpip-forward and cancel-tcpip-forward.
type ForwardedTCPHandler struct {
forwards map[string]net.Listener
sync.Mutex
}
func (h *ForwardedTCPHandler) HandleSSHRequest(ctx Context, srv *Server, req *gossh.Request) (bool, []byte) {
h.Lock()
if h.forwards == nil {
h.forwards = make(map[string]net.Listener)
}
h.Unlock()
conn := ctx.Value(ContextKeyConn).(*gossh.ServerConn)
switch req.Type {
case "tcpip-forward":
var reqPayload remoteForwardRequest
if err := gossh.Unmarshal(req.Payload, &reqPayload); err != nil {
// TODO: log parse failure
return false, []byte{}
}
if srv.ReversePortForwardingCallback == nil || !srv.ReversePortForwardingCallback(ctx, reqPayload.BindAddr, reqPayload.BindPort) {
return false, []byte("port forwarding is disabled")
}
addr := net.JoinHostPort(reqPayload.BindAddr, strconv.Itoa(int(reqPayload.BindPort)))
ln, err := net.Listen("tcp", addr)
if err != nil {
// TODO: log listen failure
return false, []byte{}
}
_, destPortStr, _ := net.SplitHostPort(ln.Addr().String())
destPort, _ := strconv.Atoi(destPortStr)
h.Lock()
h.forwards[addr] = ln
h.Unlock()
go func() {
<-ctx.Done()
h.Lock()
ln, ok := h.forwards[addr]
h.Unlock()
if ok {
ln.Close()
}
}()
go func() {
for {
c, err := ln.Accept()
if err != nil {
// TODO: log accept failure
break
}
originAddr, orignPortStr, _ := net.SplitHostPort(c.RemoteAddr().String())
originPort, _ := strconv.Atoi(orignPortStr)
payload := gossh.Marshal(&remoteForwardChannelData{
DestAddr: reqPayload.BindAddr,
DestPort: uint32(destPort),
OriginAddr: originAddr,
OriginPort: uint32(originPort),
})
go func() {
ch, reqs, err := conn.OpenChannel(forwardedTCPChannelType, payload)
if err != nil {
// TODO: log failure to open channel
log.Println(err)
c.Close()
return
}
go gossh.DiscardRequests(reqs)
go func() {
defer ch.Close()
defer c.Close()
io.Copy(ch, c)
}()
go func() {
defer ch.Close()
defer c.Close()
io.Copy(c, ch)
}()
}()
}
h.Lock()
delete(h.forwards, addr)
h.Unlock()
}()
return true, gossh.Marshal(&remoteForwardSuccess{uint32(destPort)})
case "cancel-tcpip-forward":
var reqPayload remoteForwardCancelRequest
if err := gossh.Unmarshal(req.Payload, &reqPayload); err != nil {
// TODO: log parse failure
return false, []byte{}
}
addr := net.JoinHostPort(reqPayload.BindAddr, strconv.Itoa(int(reqPayload.BindPort)))
h.Lock()
ln, ok := h.forwards[addr]
h.Unlock()
if ok {
ln.Close()
}
return true, nil
default:
return false, nil
}
}

@ -0,0 +1,83 @@
package ssh
import (
"crypto/rand"
"crypto/rsa"
"encoding/binary"
"golang.org/x/crypto/ssh"
)
func generateSigner() (ssh.Signer, error) {
key, err := rsa.GenerateKey(rand.Reader, 2048)
if err != nil {
return nil, err
}
return ssh.NewSignerFromKey(key)
}
func parsePtyRequest(s []byte) (pty Pty, ok bool) {
term, s, ok := parseString(s)
if !ok {
return
}
width32, s, ok := parseUint32(s)
if !ok {
return
}
height32, _, ok := parseUint32(s)
if !ok {
return
}
pty = Pty{
Term: term,
Window: Window{
Width: int(width32),
Height: int(height32),
},
}
return
}
func parseWinchRequest(s []byte) (win Window, ok bool) {
width32, s, ok := parseUint32(s)
if width32 < 1 {
ok = false
}
if !ok {
return
}
height32, _, ok := parseUint32(s)
if height32 < 1 {
ok = false
}
if !ok {
return
}
win = Window{
Width: int(width32),
Height: int(height32),
}
return
}
func parseString(in []byte) (out string, rest []byte, ok bool) {
if len(in) < 4 {
return
}
length := binary.BigEndian.Uint32(in)
if uint32(len(in)) < 4+length {
return
}
out = string(in[4 : 4+length])
rest = in[4+length:]
ok = true
return
}
func parseUint32(in []byte) (uint32, []byte, bool) {
if len(in) < 4 {
return 0, nil, false
}
return binary.BigEndian.Uint32(in), in[4:], true
}

@ -0,0 +1,33 @@
package ssh
import gossh "golang.org/x/crypto/ssh"
// PublicKey is an abstraction of different types of public keys.
type PublicKey interface {
gossh.PublicKey
}
// The Permissions type holds fine-grained permissions that are specific to a
// user or a specific authentication method for a user. Permissions, except for
// "source-address", must be enforced in the server application layer, after
// successful authentication.
type Permissions struct {
*gossh.Permissions
}
// A Signer can create signatures that verify against a public key.
type Signer interface {
gossh.Signer
}
// ParseAuthorizedKey parses a public key from an authorized_keys file used in
// OpenSSH according to the sshd(8) manual page.
func ParseAuthorizedKey(in []byte) (out PublicKey, comment string, options []string, rest []byte, err error) {
return gossh.ParseAuthorizedKey(in)
}
// ParsePublicKey parses an SSH public key formatted for use in
// the SSH wire protocol according to RFC 4253, section 6.6.
func ParsePublicKey(in []byte) (out PublicKey, err error) {
return gossh.ParsePublicKey(in)
}

@ -13,7 +13,6 @@ package unix
import (
"encoding/binary"
"net"
"runtime"
"syscall"
"unsafe"
@ -765,7 +764,7 @@ const px_proto_oe = 0
type SockaddrPPPoE struct {
SID uint16
Remote net.HardwareAddr
Remote []byte
Dev string
raw RawSockaddrPPPoX
}
@ -916,7 +915,7 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
}
sa := &SockaddrPPPoE{
SID: binary.BigEndian.Uint16(pp[6:8]),
Remote: net.HardwareAddr(pp[8:14]),
Remote: pp[8:14],
}
for i := 14; i < 14+IFNAMSIZ; i++ {
if pp[i] == 0 {

@ -254,6 +254,7 @@ type Ptmget C.struct_ptmget
const (
AT_FDCWD = C.AT_FDCWD
AT_SYMLINK_FOLLOW = C.AT_SYMLINK_FOLLOW
AT_SYMLINK_NOFOLLOW = C.AT_SYMLINK_NOFOLLOW
)

@ -241,6 +241,7 @@ type Winsize C.struct_winsize
const (
AT_FDCWD = C.AT_FDCWD
AT_SYMLINK_FOLLOW = C.AT_SYMLINK_FOLLOW
AT_SYMLINK_NOFOLLOW = C.AT_SYMLINK_NOFOLLOW
)

@ -411,6 +411,7 @@ type Ptmget struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x400
AT_SYMLINK_NOFOLLOW = 0x200
)

@ -418,6 +418,7 @@ type Ptmget struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x400
AT_SYMLINK_NOFOLLOW = 0x200
)

@ -416,6 +416,7 @@ type Ptmget struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x400
AT_SYMLINK_NOFOLLOW = 0x200
)

@ -418,6 +418,7 @@ type Ptmget struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x400
AT_SYMLINK_NOFOLLOW = 0x200
)

@ -436,6 +436,7 @@ type Winsize struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x4
AT_SYMLINK_NOFOLLOW = 0x2
)

@ -436,6 +436,7 @@ type Winsize struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x4
AT_SYMLINK_NOFOLLOW = 0x2
)

@ -437,6 +437,7 @@ type Winsize struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x4
AT_SYMLINK_NOFOLLOW = 0x2
)

@ -430,6 +430,7 @@ type Winsize struct {
const (
AT_FDCWD = -0x64
AT_SYMLINK_FOLLOW = 0x4
AT_SYMLINK_NOFOLLOW = 0x2
)

@ -294,7 +294,7 @@ func NewCallbackCDecl(fn interface{}) uintptr {
//sys clsidFromString(lpsz *uint16, pclsid *GUID) (ret error) = ole32.CLSIDFromString
//sys stringFromGUID2(rguid *GUID, lpsz *uint16, cchMax int32) (chars int32) = ole32.StringFromGUID2
//sys coCreateGuid(pguid *GUID) (ret error) = ole32.CoCreateGuid
//sys coTaskMemFree(address unsafe.Pointer) = ole32.CoTaskMemFree
//sys CoTaskMemFree(address unsafe.Pointer) = ole32.CoTaskMemFree
//sys rtlGetVersion(info *OsVersionInfoEx) (ret error) = ntdll.RtlGetVersion
// syscall interface implementation for other packages
@ -1302,7 +1302,7 @@ func (t Token) KnownFolderPath(folderID *KNOWNFOLDERID, flags uint32) (string, e
if err != nil {
return "", err
}
defer coTaskMemFree(unsafe.Pointer(p))
defer CoTaskMemFree(unsafe.Pointer(p))
return UTF16ToString((*[(1 << 30) - 1]uint16)(unsafe.Pointer(p))[:]), nil
}

@ -2517,7 +2517,7 @@ func coCreateGuid(pguid *GUID) (ret error) {
return
}
func coTaskMemFree(address unsafe.Pointer) {
func CoTaskMemFree(address unsafe.Pointer) {
syscall.Syscall(procCoTaskMemFree.Addr(), 1, uintptr(address), 0, 0)
return
}

@ -15,6 +15,8 @@ github.com/Unknwon/i18n
github.com/Unknwon/paginater
# github.com/andybalholm/cascadia v0.0.0-20161224141413-349dd0209470
github.com/andybalholm/cascadia
# github.com/anmitsu/go-shlex v0.0.0-20161002113705-648efa622239
github.com/anmitsu/go-shlex
# github.com/beorn7/perks v1.0.0
github.com/beorn7/perks/quantile
# github.com/blevesearch/bleve v0.0.0-20190214220507-05d86ea8f6e3
@ -112,6 +114,8 @@ github.com/facebookgo/grace/gracenet
github.com/facebookgo/httpdown
# github.com/facebookgo/stats v0.0.0-20151006221625-1b76add642e4
github.com/facebookgo/stats
# github.com/gliderlabs/ssh v0.2.2
github.com/gliderlabs/ssh
# github.com/glycerine/go-unsnap-stream v0.0.0-20180323001048-9f0cb55181dd
github.com/glycerine/go-unsnap-stream
# github.com/go-macaron/binding v0.0.0-20160711225916-9440f336b443
@ -353,7 +357,7 @@ golang.org/x/crypto/cast5
golang.org/x/crypto/openpgp/elgamal
golang.org/x/crypto/ssh/knownhosts
golang.org/x/crypto/ssh/agent
# golang.org/x/net v0.0.0-20190613194153-d28f0bde5980
# golang.org/x/net v0.0.0-20190619014844-b5b0513f8c1b
golang.org/x/net/html/charset
golang.org/x/net/html
golang.org/x/net/html/atom
@ -365,7 +369,7 @@ golang.org/x/net/internal/socks
# golang.org/x/oauth2 v0.0.0-20181101160152-c453e0c75759
golang.org/x/oauth2
golang.org/x/oauth2/internal
# golang.org/x/sys v0.0.0-20190618155005-516e3c20635f
# golang.org/x/sys v0.0.0-20190620070143-6f217b454f45
golang.org/x/sys/windows
golang.org/x/sys/windows/svc
golang.org/x/sys/unix

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