pax_global_header00006660000000000000000000000064140662762310014521gustar00rootroot0000000000000052 comment=c9fc4412c4220e738f2c504b07b7c7dcc498108d ssh-0.3.3/000077500000000000000000000000001406627623100123215ustar00rootroot00000000000000ssh-0.3.3/LICENSE000066400000000000000000000027041406627623100133310ustar00rootroot00000000000000Copyright (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. ssh-0.3.3/README.md000066400000000000000000000147101406627623100136030ustar00rootroot00000000000000# 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. —[@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)] ## License [BSD](LICENSE) ssh-0.3.3/_examples/000077500000000000000000000000001406627623100142765ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-docker/000077500000000000000000000000001406627623100163405ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-docker/Dockerfile000066400000000000000000000000601406627623100203260ustar00rootroot00000000000000FROM alpine RUN apk add -U jq ENTRYPOINT ["jq"] ssh-0.3.3/_examples/ssh-docker/README.md000066400000000000000000000103731406627623100176230ustar00rootroot00000000000000# SSH Docker Example Run docker containers over SSH. You can even pipe things into them too! # Installation / Prep We're going to build JQ as an SSH service using the Glider Labs SSH package. If you haven't installed GoLang and docker yet, see the doc's for help getting your environment setup. Install the Glider Labs SSH package `go get github.com/gliderlabs/ssh` Build the example docker container with `docker build --rm -t jq .` # Usage Run the SSH server with `go run docker.go` This SSH service uses the user name passed into the connection to key the desired docker image. So to use jq over our SSH server we would say: `ssh jq@localhost -p 2222` If we run this command we will see ``` jq - commandline JSON processor [version 1.5] Usage: jq [options] [file...] jq is a tool for processing JSON inputs, applying the given filter to its JSON text inputs and producing the filter's results as JSON on standard output. The simplest filter is ., which is the identity filter, copying jq's input to its output unmodified (except for formatting). For more advanced filters see the jq(1) manpage ("man jq") and/or https://stedolan.github.io/jq Some of the options include: -c compact instead of pretty-printed output; -n use `null` as the single input value; -e set the exit status code based on the output; -s read (slurp) all inputs into an array; apply filter to it; -r output raw strings, not JSON texts; -R read raw strings, not JSON texts; -C colorize JSON; -M monochrome (don't colorize JSON); -S sort keys of objects on output; --tab use tabs for indentation; --arg a v set variable $a to value ; --argjson a v set variable $a to JSON value ; --slurpfile a f set variable $a to an array of JSON texts read from ; See the manpage for more options. Connection to localhost closed. ``` JQ's help text! It's working! Now let's pipe some json into our SSH service and marvel at the awesomeness. `curl -s https://api.github.com/orgs/gliderlabs | ssh jq@localhost -p 2222 .` ```json { "login": "gliderlabs", "id": 8484931, "url": "https://api.github.com/orgs/gliderlabs", "repos_url": "https://api.github.com/orgs/gliderlabs/repos", "events_url": "https://api.github.com/orgs/gliderlabs/events", "hooks_url": "https://api.github.com/orgs/gliderlabs/hooks", "issues_url": "https://api.github.com/orgs/gliderlabs/issues", "members_url": "https://api.github.com/orgs/gliderlabs/members{/member}", "public_members_url": "https://api.github.com/orgs/gliderlabs/public_members{/member}", "avatar_url": "https://avatars3.githubusercontent.com/u/8484931?v=4", "description": "", "name": "Glider Labs", "company": null, "blog": "http://gliderlabs.com", "location": "Austin, TX", "email": "team@gliderlabs.com", "has_organization_projects": true, "has_repository_projects": true, "public_repos": 29, "public_gists": 0, "followers": 0, "following": 0, "html_url": "https://github.com/gliderlabs", "created_at": "2014-08-18T23:25:37Z", "updated_at": "2017-08-21T09:52:17Z", "type": "Organization" } ``` # Conclusion We built JQ as a service over SSH in Go using the Glider Labs SSH package. We showed how you can run docker containers through the service as well as how to pipe stuff into your SSH service. # Troubleshooting A new host key is generated each time we run the server so you'll probably see this error on the second run. ``` @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that a host key has just been changed. The fingerprint for the RSA key sent by the remote host is SHA256:9dyZ8KrMCPGvDqECggoDFyz51gA6DdHa9zpfl/5Kgos. Please contact your system administrator. Add correct host key in /Users/murr/.ssh/known_hosts to get rid of this message. Offending RSA key in /Users/murr/.ssh/known_hosts:7 RSA host key for [localhost]:2222 has changed and you have requested strict checking. Host key verification failed. ``` To bypass this error, regnerate your host key with `ssh-keygen -R "[localhost]:2222"` ssh-0.3.3/_examples/ssh-docker/docker.go000066400000000000000000000050041406627623100201350ustar00rootroot00000000000000package main import ( "context" "fmt" "io" "log" "github.com/docker/docker/api/types" "github.com/docker/docker/api/types/container" "github.com/docker/docker/client" "github.com/docker/docker/pkg/stdcopy" "github.com/gliderlabs/ssh" ) func main() { ssh.Handle(func(sess ssh.Session) { _, _, isTty := sess.Pty() cfg := &container.Config{ Image: sess.User(), Cmd: sess.Command(), Env: sess.Environ(), Tty: isTty, OpenStdin: true, AttachStderr: true, AttachStdin: true, AttachStdout: true, StdinOnce: true, Volumes: make(map[string]struct{}), } status, cleanup, err := dockerRun(cfg, sess) defer cleanup() if err != nil { fmt.Fprintln(sess, err) log.Println(err) } sess.Exit(int(status)) }) log.Println("starting ssh server on port 2222...") log.Fatal(ssh.ListenAndServe(":2222", nil)) } func dockerRun(cfg *container.Config, sess ssh.Session) (status int64, cleanup func(), err error) { docker, err := client.NewEnvClient() if err != nil { panic(err) } status = 255 cleanup = func() {} ctx := context.Background() res, err := docker.ContainerCreate(ctx, cfg, nil, nil, "") if err != nil { return } cleanup = func() { docker.ContainerRemove(ctx, res.ID, types.ContainerRemoveOptions{}) } opts := types.ContainerAttachOptions{ Stdin: cfg.AttachStdin, Stdout: cfg.AttachStdout, Stderr: cfg.AttachStderr, Stream: true, } stream, err := docker.ContainerAttach(ctx, res.ID, opts) if err != nil { return } cleanup = func() { docker.ContainerRemove(ctx, res.ID, types.ContainerRemoveOptions{}) stream.Close() } outputErr := make(chan error) go func() { var err error if cfg.Tty { _, err = io.Copy(sess, stream.Reader) } else { _, err = stdcopy.StdCopy(sess, sess.Stderr(), stream.Reader) } outputErr <- err }() go func() { defer stream.CloseWrite() io.Copy(stream.Conn, sess) }() err = docker.ContainerStart(ctx, res.ID, types.ContainerStartOptions{}) if err != nil { return } if cfg.Tty { _, winCh, _ := sess.Pty() go func() { for win := range winCh { err := docker.ContainerResize(ctx, res.ID, types.ResizeOptions{ Height: uint(win.Height), Width: uint(win.Width), }) if err != nil { log.Println(err) break } } }() } resultC, errC := docker.ContainerWait(ctx, res.ID, container.WaitConditionNotRunning) select { case err = <-errC: return case result := <-resultC: status = result.StatusCode } err = <-outputErr return } ssh-0.3.3/_examples/ssh-forwardagent/000077500000000000000000000000001406627623100175545ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-forwardagent/forwardagent.go000066400000000000000000000012531406627623100225670ustar00rootroot00000000000000package main import ( "fmt" "log" "os/exec" "github.com/gliderlabs/ssh" ) func main() { ssh.Handle(func(s ssh.Session) { cmd := exec.Command("ssh-add", "-l") if ssh.AgentRequested(s) { l, err := ssh.NewAgentListener() if err != nil { log.Fatal(err) } defer l.Close() go ssh.ForwardAgentConnections(l, s) cmd.Env = append(s.Environ(), fmt.Sprintf("%s=%s", "SSH_AUTH_SOCK", l.Addr().String())) } else { cmd.Env = s.Environ() } cmd.Stdout = s cmd.Stderr = s.Stderr() if err := cmd.Run(); err != nil { log.Println(err) return } }) log.Println("starting ssh server on port 2222...") log.Fatal(ssh.ListenAndServe(":2222", nil)) } ssh-0.3.3/_examples/ssh-pty/000077500000000000000000000000001406627623100157055ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-pty/pty.go000066400000000000000000000017021406627623100170500ustar00rootroot00000000000000package main import ( "fmt" "io" "log" "os" "os/exec" "syscall" "unsafe" "github.com/gliderlabs/ssh" "github.com/creack/pty" ) func setWinsize(f *os.File, w, h int) { syscall.Syscall(syscall.SYS_IOCTL, f.Fd(), uintptr(syscall.TIOCSWINSZ), uintptr(unsafe.Pointer(&struct{ h, w, x, y uint16 }{uint16(h), uint16(w), 0, 0}))) } func main() { ssh.Handle(func(s ssh.Session) { cmd := exec.Command("top") ptyReq, winCh, isPty := s.Pty() if isPty { cmd.Env = append(cmd.Env, fmt.Sprintf("TERM=%s", ptyReq.Term)) f, err := pty.Start(cmd) if err != nil { panic(err) } go func() { for win := range winCh { setWinsize(f, win.Width, win.Height) } }() go func() { io.Copy(f, s) // stdin }() io.Copy(s, f) // stdout cmd.Wait() } else { io.WriteString(s, "No PTY requested.\n") s.Exit(1) } }) log.Println("starting ssh server on port 2222...") log.Fatal(ssh.ListenAndServe(":2222", nil)) } ssh-0.3.3/_examples/ssh-publickey/000077500000000000000000000000001406627623100170605ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-publickey/public_key.go000066400000000000000000000011441406627623100215350ustar00rootroot00000000000000package main import ( "fmt" "io" "log" "github.com/gliderlabs/ssh" gossh "golang.org/x/crypto/ssh" ) func main() { ssh.Handle(func(s ssh.Session) { authorizedKey := gossh.MarshalAuthorizedKey(s.PublicKey()) io.WriteString(s, fmt.Sprintf("public key used by %s:\n", s.User())) s.Write(authorizedKey) }) publicKeyOption := ssh.PublicKeyAuth(func(ctx ssh.Context, key ssh.PublicKey) bool { return true // allow all keys, or use ssh.KeysEqual() to compare against known keys }) log.Println("starting ssh server on port 2222...") log.Fatal(ssh.ListenAndServe(":2222", nil, publicKeyOption)) } ssh-0.3.3/_examples/ssh-remoteforward/000077500000000000000000000000001406627623100177515ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-remoteforward/portforward.go000066400000000000000000000016701406627623100226550ustar00rootroot00000000000000package main import ( "io" "log" "github.com/gliderlabs/ssh" ) func main() { log.Println("starting ssh server on port 2222...") forwardHandler := &ssh.ForwardedTCPHandler{} server := ssh.Server{ LocalPortForwardingCallback: ssh.LocalPortForwardingCallback(func(ctx ssh.Context, dhost string, dport uint32) bool { log.Println("Accepted forward", dhost, dport) return true }), Addr: ":2222", Handler: ssh.Handler(func(s ssh.Session) { io.WriteString(s, "Remote forwarding available...\n") select {} }), ReversePortForwardingCallback: ssh.ReversePortForwardingCallback(func(ctx ssh.Context, host string, port uint32) bool { log.Println("attempt to bind", host, port, "granted") return true }), RequestHandlers: map[string]ssh.RequestHandler{ "tcpip-forward": forwardHandler.HandleSSHRequest, "cancel-tcpip-forward": forwardHandler.HandleSSHRequest, }, } log.Fatal(server.ListenAndServe()) } ssh-0.3.3/_examples/ssh-simple/000077500000000000000000000000001406627623100163625ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-simple/simple.go000066400000000000000000000004351406627623100202040ustar00rootroot00000000000000package main import ( "fmt" "io" "log" "github.com/gliderlabs/ssh" ) func main() { ssh.Handle(func(s ssh.Session) { io.WriteString(s, fmt.Sprintf("Hello %s\n", s.User())) }) log.Println("starting ssh server on port 2222...") log.Fatal(ssh.ListenAndServe(":2222", nil)) } ssh-0.3.3/_examples/ssh-timeouts/000077500000000000000000000000001406627623100167425ustar00rootroot00000000000000ssh-0.3.3/_examples/ssh-timeouts/timeouts.go000066400000000000000000000014131406627623100211410ustar00rootroot00000000000000package main import ( "log" "time" "github.com/gliderlabs/ssh" ) var ( DeadlineTimeout = 30 * time.Second IdleTimeout = 10 * time.Second ) func main() { ssh.Handle(func(s ssh.Session) { log.Println("new connection") i := 0 for { i += 1 log.Println("active seconds:", i) select { case <-time.After(time.Second): continue case <-s.Context().Done(): log.Println("connection closed") return } } }) log.Println("starting ssh server on port 2222...") log.Printf("connections will only last %s\n", DeadlineTimeout) log.Printf("and timeout after %s of no activity\n", IdleTimeout) server := &ssh.Server{ Addr: ":2222", MaxTimeout: DeadlineTimeout, IdleTimeout: IdleTimeout, } log.Fatal(server.ListenAndServe()) } ssh-0.3.3/agent.go000066400000000000000000000037771406627623100137640ustar00rootroot00000000000000package 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) } } ssh-0.3.3/circle.yml000066400000000000000000000007361406627623100143130ustar00rootroot00000000000000version: 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-1.12: docker: - image: golang:1.12 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-1.12 ssh-0.3.3/conn.go000066400000000000000000000020201406627623100135770ustar00rootroot00000000000000package 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) } } ssh-0.3.3/context.go000066400000000000000000000117571406627623100143470ustar00rootroot00000000000000package 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 { if addr, ok := ctx.Value(ContextKeyRemoteAddr).(net.Addr); ok { return addr } return nil } func (ctx *sshContext) LocalAddr() net.Addr { return ctx.Value(ContextKeyLocalAddr).(net.Addr) } func (ctx *sshContext) Permissions() *Permissions { return ctx.Value(ContextKeyPermissions).(*Permissions) } ssh-0.3.3/context_test.go000066400000000000000000000021161406627623100153730ustar00rootroot00000000000000package ssh import "testing" func TestSetPermissions(t *testing.T) { t.Parallel() permsExt := map[string]string{ "foo": "bar", } session, _, cleanup := newTestSessionWithOptions(t, &Server{ Handler: func(s Session) { if _, ok := s.Permissions().Extensions["foo"]; !ok { t.Fatalf("got %#v; want %#v", s.Permissions().Extensions, permsExt) } }, }, nil, PasswordAuth(func(ctx Context, password string) bool { ctx.Permissions().Extensions = permsExt return true })) defer cleanup() if err := session.Run(""); err != nil { t.Fatal(err) } } func TestSetValue(t *testing.T) { t.Parallel() value := map[string]string{ "foo": "bar", } key := "testValue" session, _, cleanup := newTestSessionWithOptions(t, &Server{ Handler: func(s Session) { v := s.Context().Value(key).(map[string]string) if v["foo"] != value["foo"] { t.Fatalf("got %#v; want %#v", v, value) } }, }, nil, PasswordAuth(func(ctx Context, password string) bool { ctx.SetValue(key, value) return true })) defer cleanup() if err := session.Run(""); err != nil { t.Fatal(err) } } ssh-0.3.3/doc.go000066400000000000000000000033611406627623100134200ustar00rootroot00000000000000/* 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 ssh-0.3.3/example_test.go000066400000000000000000000015051406627623100153430ustar00rootroot00000000000000package ssh_test import ( "io" "io/ioutil" "github.com/gliderlabs/ssh" ) func ExampleListenAndServe() { ssh.ListenAndServe(":2222", func(s ssh.Session) { io.WriteString(s, "Hello world\n") }) } func ExamplePasswordAuth() { ssh.ListenAndServe(":2222", nil, ssh.PasswordAuth(func(ctx ssh.Context, pass string) bool { return pass == "secret" }), ) } func ExampleNoPty() { ssh.ListenAndServe(":2222", nil, ssh.NoPty()) } func ExamplePublicKeyAuth() { ssh.ListenAndServe(":2222", nil, ssh.PublicKeyAuth(func(ctx ssh.Context, key ssh.PublicKey) bool { data, _ := ioutil.ReadFile("/path/to/allowed/key.pub") allowed, _, _, _, _ := ssh.ParseAuthorizedKey(data) return ssh.KeysEqual(key, allowed) }), ) } func ExampleHostKeyFile() { ssh.ListenAndServe(":2222", nil, ssh.HostKeyFile("/path/to/host/key")) } ssh-0.3.3/go.mod000066400000000000000000000003601406627623100134260ustar00rootroot00000000000000module github.com/gliderlabs/ssh go 1.12 require ( github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be golang.org/x/crypto v0.0.0-20210616213533-5ff15b29337e golang.org/x/sys v0.0.0-20210616094352-59db8d763f22 // indirect ) ssh-0.3.3/go.sum000066400000000000000000000025301406627623100134540ustar00rootroot00000000000000github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be h1:9AeTilPcZAjCFIImctFaOjnTIavg87rW78vTPkQqLI8= github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be/go.mod h1:ySMOLuWl6zY27l47sB3qLNK6tF2fkHG55UZxx8oIVo4= golang.org/x/crypto v0.0.0-20210616213533-5ff15b29337e h1:gsTQYXdTw2Gq7RBsWvlQ91b+aEQ6bXFUngBGuR8sPpI= golang.org/x/crypto v0.0.0-20210616213533-5ff15b29337e/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc= golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg= golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs= golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.0.0-20210616094352-59db8d763f22 h1:RqytpXGR1iVNX7psjB3ff8y7sNFinVFvkx1c8SjBkio= golang.org/x/sys v0.0.0-20210616094352-59db8d763f22/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1 h1:v+OssWQX+hTHEmOBgwxdZxK4zHq3yOs8F9J7mk0PY8E= golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo= golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ= golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ= ssh-0.3.3/options.go000066400000000000000000000034261406627623100143500ustar00rootroot00000000000000package 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 } } func KeyboardInteractiveAuth(fn KeyboardInteractiveHandler) Option { return func(srv *Server) error { srv.KeyboardInteractiveHandler = fn 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 } } ssh-0.3.3/options_test.go000066400000000000000000000047531406627623100154130ustar00rootroot00000000000000package ssh import ( "net" "strings" "sync/atomic" "testing" gossh "golang.org/x/crypto/ssh" ) func newTestSessionWithOptions(t *testing.T, srv *Server, cfg *gossh.ClientConfig, options ...Option) (*gossh.Session, *gossh.Client, func()) { for _, option := range options { if err := srv.SetOption(option); err != nil { t.Fatal(err) } } return newTestSession(t, srv, cfg) } func TestPasswordAuth(t *testing.T) { t.Parallel() testUser := "testuser" testPass := "testpass" session, _, cleanup := newTestSessionWithOptions(t, &Server{ Handler: func(s Session) { // noop }, }, &gossh.ClientConfig{ User: testUser, Auth: []gossh.AuthMethod{ gossh.Password(testPass), }, HostKeyCallback: gossh.InsecureIgnoreHostKey(), }, PasswordAuth(func(ctx Context, password string) bool { if ctx.User() != testUser { t.Fatalf("user = %#v; want %#v", ctx.User(), testUser) } if password != testPass { t.Fatalf("user = %#v; want %#v", password, testPass) } return true })) defer cleanup() if err := session.Run(""); err != nil { t.Fatal(err) } } func TestPasswordAuthBadPass(t *testing.T) { t.Parallel() l := newLocalListener() srv := &Server{Handler: func(s Session) {}} srv.SetOption(PasswordAuth(func(ctx Context, password string) bool { return false })) go srv.serveOnce(l) _, err := gossh.Dial("tcp", l.Addr().String(), &gossh.ClientConfig{ User: "testuser", Auth: []gossh.AuthMethod{ gossh.Password("testpass"), }, HostKeyCallback: gossh.InsecureIgnoreHostKey(), }) if err != nil { if !strings.Contains(err.Error(), "unable to authenticate") { t.Fatal(err) } } } type wrappedConn struct { net.Conn written int32 } func (c *wrappedConn) Write(p []byte) (n int, err error) { n, err = c.Conn.Write(p) atomic.AddInt32(&(c.written), int32(n)) return } func TestConnWrapping(t *testing.T) { t.Parallel() var wrapped *wrappedConn session, _, cleanup := newTestSessionWithOptions(t, &Server{ Handler: func(s Session) { // nothing }, }, &gossh.ClientConfig{ User: "testuser", Auth: []gossh.AuthMethod{ gossh.Password("testpass"), }, HostKeyCallback: gossh.InsecureIgnoreHostKey(), }, PasswordAuth(func(ctx Context, password string) bool { return true }), WrapConn(func(ctx Context, conn net.Conn) net.Conn { wrapped = &wrappedConn{conn, 0} return wrapped })) defer cleanup() if err := session.Shell(); err != nil { t.Fatal(err) } if atomic.LoadInt32(&(wrapped.written)) == 0 { t.Fatal("wrapped conn not written to") } } ssh-0.3.3/server.go000066400000000000000000000310301406627623100141530ustar00rootroot00000000000000package 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 SubsystemHandler func(s Session) var DefaultSubsystemHandlers = map[string]SubsystemHandler{} 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 ConnectionFailedCallback ConnectionFailedCallback // callback to report connection failures 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 // SubsystemHandlers are handlers which are similar to the usual SSH command // handlers, but handle named subsystems. SubsystemHandlers map[string]SubsystemHandler listenerWg sync.WaitGroup mu sync.RWMutex listeners map[net.Listener]struct{} conns map[*gossh.ServerConn]struct{} connWg sync.WaitGroup doneChan chan struct{} } func (srv *Server) ensureHostSigner() error { srv.mu.Lock() defer srv.mu.Unlock() 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 } } if srv.SubsystemHandlers == nil { srv.SubsystemHandlers = map[string]SubsystemHandler{} for k, v := range DefaultSubsystemHandlers { srv.SubsystemHandlers[k] = v } } } func (srv *Server) config(ctx Context) *gossh.ServerConfig { srv.mu.RLock() defer srv.mu.RUnlock() 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 && srv.KeyboardInteractiveHandler == 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) { applyConnMetadata(ctx, conn) 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.mu.Lock() defer srv.mu.Unlock() 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) { ctx, cancel := newContext(srv) if srv.ConnCallback != nil { cbConn := srv.ConnCallback(ctx, newConn) if cbConn == nil { newConn.Close() return } newConn = cbConn } 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 { if srv.ConnectionFailedCallback != nil { srv.ConnectionFailedCallback(conn, err) } 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) { srv.mu.Lock() defer srv.mu.Unlock() // these are later added via AddHostKey on ServerConfig, which performs the // check for one of every algorithm. // This check is based on the AddHostKey method from the x/crypto/ssh // library. This allows us to only keep one active key for each type on a // server at once. So, if you're dynamically updating keys at runtime, this // list will not keep growing. for i, k := range srv.HostSigners { if k.PublicKey().Type() == key.PublicKey().Type() { srv.HostSigners[i] = key return } } srv.HostSigners = append(srv.HostSigners, key) } // SetOption runs a functional option against the server. func (srv *Server) SetOption(option Option) error { // NOTE: there is a potential race here for any option that doesn't call an // internal method. We can't actually lock here because if something calls // (as an example) AddHostKey, it will deadlock. //srv.mu.Lock() //defer srv.mu.Unlock() 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() } } ssh-0.3.3/server_test.go000066400000000000000000000043701406627623100152210ustar00rootroot00000000000000package ssh import ( "bytes" "context" "io" "testing" "time" ) func TestAddHostKey(t *testing.T) { s := Server{} signer, err := generateSigner() if err != nil { t.Fatal(err) } s.AddHostKey(signer) if len(s.HostSigners) != 1 { t.Fatal("Key was not properly added") } signer, err = generateSigner() if err != nil { t.Fatal(err) } s.AddHostKey(signer) if len(s.HostSigners) != 1 { t.Fatal("Key was not properly replaced") } } func TestServerShutdown(t *testing.T) { l := newLocalListener() testBytes := []byte("Hello world\n") s := &Server{ Handler: func(s Session) { s.Write(testBytes) time.Sleep(50 * time.Millisecond) }, } go func() { err := s.Serve(l) if err != nil && err != ErrServerClosed { t.Fatal(err) } }() sessDone := make(chan struct{}) sess, _, cleanup := newClientSession(t, l.Addr().String(), nil) go func() { defer cleanup() defer close(sessDone) var stdout bytes.Buffer sess.Stdout = &stdout if err := sess.Run(""); err != nil { t.Fatal(err) } if !bytes.Equal(stdout.Bytes(), testBytes) { t.Fatalf("expected = %s; got %s", testBytes, stdout.Bytes()) } }() srvDone := make(chan struct{}) go func() { defer close(srvDone) err := s.Shutdown(context.Background()) if err != nil { t.Fatal(err) } }() timeout := time.After(2 * time.Second) select { case <-timeout: t.Fatal("timeout") return case <-srvDone: // TODO: add timeout for sessDone <-sessDone return } } func TestServerClose(t *testing.T) { l := newLocalListener() s := &Server{ Handler: func(s Session) { time.Sleep(5 * time.Second) }, } go func() { err := s.Serve(l) if err != nil && err != ErrServerClosed { t.Fatal(err) } }() clientDoneChan := make(chan struct{}) closeDoneChan := make(chan struct{}) sess, _, cleanup := newClientSession(t, l.Addr().String(), nil) go func() { defer cleanup() defer close(clientDoneChan) <-closeDoneChan if err := sess.Run(""); err != nil && err != io.EOF { t.Fatal(err) } }() go func() { err := s.Close() if err != nil { t.Fatal(err) } close(closeDoneChan) }() timeout := time.After(100 * time.Millisecond) select { case <-timeout: t.Error("timeout") return case <-s.getDoneChan(): <-clientDoneChan return } } ssh-0.3.3/session.go000066400000000000000000000225121406627623100143350ustar00rootroot00000000000000package 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 // crypto/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 // Subsystem returns the subsystem requested by the user. Subsystem() 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) // Break regisers a channel to receive notifications of break requests sent // from the client. The channel must handle break requests, or it will block // the request handling loop. Registering nil will unregister the channel. // During the time that no channel is registered, breaks are ignored. Break(c chan<- bool) } // 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, subsystemHandlers: srv.SubsystemHandlers, ctx: ctx, } sess.handleRequests(reqs) } type session struct { sync.Mutex gossh.Channel conn *gossh.ServerConn handler Handler subsystemHandlers map[string]SubsystemHandler handled bool exited bool pty *Pty winch chan Window env []string ptyCb PtyCallback sessReqCb SessionRequestCallback rawCmd string subsystem string ctx Context sigCh chan<- Signal sigBuf []Signal breakCh chan<- bool } 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) Subsystem() string { return sess.subsystem } 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) Break(c chan<- bool) { sess.Lock() defer sess.Unlock() sess.breakCh = c } 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 "subsystem": if sess.handled { req.Reply(false, nil) continue } var payload = struct{ Value string }{} gossh.Unmarshal(req.Payload, &payload) sess.subsystem = 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 } handler := sess.subsystemHandlers[payload.Value] if handler == nil { handler = sess.subsystemHandlers["default"] } if handler == nil { req.Reply(false, nil) continue } sess.handled = true req.Reply(true, nil) go func() { 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) case "break": ok := false sess.Lock() if sess.breakCh != nil { sess.breakCh <- true ok = true } req.Reply(ok, nil) sess.Unlock() default: // TODO: debug log req.Reply(false, nil) } } } ssh-0.3.3/session_test.go000066400000000000000000000240601406627623100153740ustar00rootroot00000000000000package ssh import ( "bytes" "fmt" "io" "net" "testing" gossh "golang.org/x/crypto/ssh" ) func (srv *Server) serveOnce(l net.Listener) error { srv.ensureHandlers() if err := srv.ensureHostSigner(); err != nil { return err } conn, e := l.Accept() if e != nil { return e } srv.ChannelHandlers = map[string]ChannelHandler{ "session": DefaultSessionHandler, "direct-tcpip": DirectTCPIPHandler, } srv.HandleConn(conn) return nil } func newLocalListener() net.Listener { l, err := net.Listen("tcp", "127.0.0.1:0") if err != nil { if l, err = net.Listen("tcp6", "[::1]:0"); err != nil { panic(fmt.Sprintf("failed to listen on a port: %v", err)) } } return l } func newClientSession(t *testing.T, addr string, config *gossh.ClientConfig) (*gossh.Session, *gossh.Client, func()) { if config == nil { config = &gossh.ClientConfig{ User: "testuser", Auth: []gossh.AuthMethod{ gossh.Password("testpass"), }, } } if config.HostKeyCallback == nil { config.HostKeyCallback = gossh.InsecureIgnoreHostKey() } client, err := gossh.Dial("tcp", addr, config) if err != nil { t.Fatal(err) } session, err := client.NewSession() if err != nil { t.Fatal(err) } return session, client, func() { session.Close() client.Close() } } func newTestSession(t *testing.T, srv *Server, cfg *gossh.ClientConfig) (*gossh.Session, *gossh.Client, func()) { l := newLocalListener() go srv.serveOnce(l) return newClientSession(t, l.Addr().String(), cfg) } func TestStdout(t *testing.T) { t.Parallel() testBytes := []byte("Hello world\n") session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { s.Write(testBytes) }, }, nil) defer cleanup() var stdout bytes.Buffer session.Stdout = &stdout if err := session.Run(""); err != nil { t.Fatal(err) } if !bytes.Equal(stdout.Bytes(), testBytes) { t.Fatalf("stdout = %#v; want %#v", stdout.Bytes(), testBytes) } } func TestStderr(t *testing.T) { t.Parallel() testBytes := []byte("Hello world\n") session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { s.Stderr().Write(testBytes) }, }, nil) defer cleanup() var stderr bytes.Buffer session.Stderr = &stderr if err := session.Run(""); err != nil { t.Fatal(err) } if !bytes.Equal(stderr.Bytes(), testBytes) { t.Fatalf("stderr = %#v; want %#v", stderr.Bytes(), testBytes) } } func TestStdin(t *testing.T) { t.Parallel() testBytes := []byte("Hello world\n") session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { io.Copy(s, s) // stdin back into stdout }, }, nil) defer cleanup() var stdout bytes.Buffer session.Stdout = &stdout session.Stdin = bytes.NewBuffer(testBytes) if err := session.Run(""); err != nil { t.Fatal(err) } if !bytes.Equal(stdout.Bytes(), testBytes) { t.Fatalf("stdout = %#v; want %#v given stdin = %#v", stdout.Bytes(), testBytes, testBytes) } } func TestUser(t *testing.T) { t.Parallel() testUser := []byte("progrium") session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { io.WriteString(s, s.User()) }, }, &gossh.ClientConfig{ User: string(testUser), }) defer cleanup() var stdout bytes.Buffer session.Stdout = &stdout if err := session.Run(""); err != nil { t.Fatal(err) } if !bytes.Equal(stdout.Bytes(), testUser) { t.Fatalf("stdout = %#v; want %#v given user = %#v", stdout.Bytes(), testUser, string(testUser)) } } func TestDefaultExitStatusZero(t *testing.T) { t.Parallel() session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { // noop }, }, nil) defer cleanup() err := session.Run("") if err != nil { t.Fatalf("expected nil but got %v", err) } } func TestExplicitExitStatusZero(t *testing.T) { t.Parallel() session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { s.Exit(0) }, }, nil) defer cleanup() err := session.Run("") if err != nil { t.Fatalf("expected nil but got %v", err) } } func TestExitStatusNonZero(t *testing.T) { t.Parallel() session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { s.Exit(1) }, }, nil) defer cleanup() err := session.Run("") e, ok := err.(*gossh.ExitError) if !ok { t.Fatalf("expected ExitError but got %T", err) } if e.ExitStatus() != 1 { t.Fatalf("exit-status = %#v; want %#v", e.ExitStatus(), 1) } } func TestPty(t *testing.T) { t.Parallel() term := "xterm" winWidth := 40 winHeight := 80 done := make(chan bool) session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { ptyReq, _, isPty := s.Pty() if !isPty { t.Fatalf("expected pty but none requested") } if ptyReq.Term != term { t.Fatalf("expected term %#v but got %#v", term, ptyReq.Term) } if ptyReq.Window.Width != winWidth { t.Fatalf("expected window width %#v but got %#v", winWidth, ptyReq.Window.Width) } if ptyReq.Window.Height != winHeight { t.Fatalf("expected window height %#v but got %#v", winHeight, ptyReq.Window.Height) } close(done) }, }, nil) defer cleanup() if err := session.RequestPty(term, winHeight, winWidth, gossh.TerminalModes{}); err != nil { t.Fatalf("expected nil but got %v", err) } if err := session.Shell(); err != nil { t.Fatalf("expected nil but got %v", err) } <-done } func TestPtyResize(t *testing.T) { t.Parallel() winch0 := Window{40, 80} winch1 := Window{80, 160} winch2 := Window{20, 40} winches := make(chan Window) done := make(chan bool) session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { ptyReq, winCh, isPty := s.Pty() if !isPty { t.Fatalf("expected pty but none requested") } if ptyReq.Window != winch0 { t.Fatalf("expected window %#v but got %#v", winch0, ptyReq.Window) } for win := range winCh { winches <- win } close(done) }, }, nil) defer cleanup() // winch0 if err := session.RequestPty("xterm", winch0.Height, winch0.Width, gossh.TerminalModes{}); err != nil { t.Fatalf("expected nil but got %v", err) } if err := session.Shell(); err != nil { t.Fatalf("expected nil but got %v", err) } gotWinch := <-winches if gotWinch != winch0 { t.Fatalf("expected window %#v but got %#v", winch0, gotWinch) } // winch1 winchMsg := struct{ w, h uint32 }{uint32(winch1.Width), uint32(winch1.Height)} ok, err := session.SendRequest("window-change", true, gossh.Marshal(&winchMsg)) if err == nil && !ok { t.Fatalf("unexpected error or bad reply on send request") } gotWinch = <-winches if gotWinch != winch1 { t.Fatalf("expected window %#v but got %#v", winch1, gotWinch) } // winch2 winchMsg = struct{ w, h uint32 }{uint32(winch2.Width), uint32(winch2.Height)} ok, err = session.SendRequest("window-change", true, gossh.Marshal(&winchMsg)) if err == nil && !ok { t.Fatalf("unexpected error or bad reply on send request") } gotWinch = <-winches if gotWinch != winch2 { t.Fatalf("expected window %#v but got %#v", winch2, gotWinch) } session.Close() <-done } func TestSignals(t *testing.T) { t.Parallel() // errChan lets us get errors back from the session errChan := make(chan error, 5) // doneChan lets us specify that we should exit. doneChan := make(chan interface{}) session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { // We need to use a buffered channel here, otherwise it's possible for the // second call to Signal to get discarded. signals := make(chan Signal, 2) s.Signals(signals) select { case sig := <-signals: if sig != SIGINT { errChan <- fmt.Errorf("expected signal %v but got %v", SIGINT, sig) return } case <-doneChan: errChan <- fmt.Errorf("Unexpected done") return } select { case sig := <-signals: if sig != SIGKILL { errChan <- fmt.Errorf("expected signal %v but got %v", SIGKILL, sig) return } case <-doneChan: errChan <- fmt.Errorf("Unexpected done") return } }, }, nil) defer cleanup() go func() { session.Signal(gossh.SIGINT) session.Signal(gossh.SIGKILL) }() go func() { errChan <- session.Run("") }() err := <-errChan close(doneChan) if err != nil { t.Fatalf("expected nil but got %v", err) } } func TestBreakWithChanRegistered(t *testing.T) { t.Parallel() // errChan lets us get errors back from the session errChan := make(chan error, 5) // doneChan lets us specify that we should exit. doneChan := make(chan interface{}) breakChan := make(chan bool) readyToReceiveBreak := make(chan bool) session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { s.Break(breakChan) // register a break channel with the session readyToReceiveBreak <- true select { case <-breakChan: io.WriteString(s, "break") case <-doneChan: errChan <- fmt.Errorf("Unexpected done") return } }, }, nil) defer cleanup() var stdout bytes.Buffer session.Stdout = &stdout go func() { errChan <- session.Run("") }() <-readyToReceiveBreak ok, err := session.SendRequest("break", true, nil) if err != nil { t.Fatalf("expected nil but got %v", err) } if ok != true { t.Fatalf("expected true but got %v", ok) } err = <-errChan close(doneChan) if err != nil { t.Fatalf("expected nil but got %v", err) } if !bytes.Equal(stdout.Bytes(), []byte("break")) { t.Fatalf("stdout = %#v, expected 'break'", stdout.Bytes()) } } func TestBreakWithoutChanRegistered(t *testing.T) { t.Parallel() // errChan lets us get errors back from the session errChan := make(chan error, 5) // doneChan lets us specify that we should exit. doneChan := make(chan interface{}) waitUntilAfterBreakSent := make(chan bool) session, _, cleanup := newTestSession(t, &Server{ Handler: func(s Session) { <-waitUntilAfterBreakSent }, }, nil) defer cleanup() var stdout bytes.Buffer session.Stdout = &stdout go func() { errChan <- session.Run("") }() ok, err := session.SendRequest("break", true, nil) if err != nil { t.Fatalf("expected nil but got %v", err) } if ok != false { t.Fatalf("expected false but got %v", ok) } waitUntilAfterBreakSent <- true err = <-errChan close(doneChan) if err != nil { t.Fatalf("expected nil but got %v", err) } } ssh-0.3.3/ssh.go000066400000000000000000000077331406627623100134570ustar00rootroot00000000000000package 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(ctx Context, 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 // ConnectionFailedCallback is a hook for reporting failed connections // Please note: the net.Conn is likely to be closed at this point type ConnectionFailedCallback func(conn net.Conn, err error) // 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) } ssh-0.3.3/ssh_test.go000066400000000000000000000003631406627623100145060ustar00rootroot00000000000000package ssh import ( "testing" ) func TestKeysEqual(t *testing.T) { defer func() { if r := recover(); r != nil { t.Errorf("The code did panic") } }() if KeysEqual(nil, nil) { t.Error("two nil keys should not return true") } } ssh-0.3.3/tcpip.go000066400000000000000000000110261406627623100137670ustar00rootroot00000000000000package 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 } } ssh-0.3.3/tcpip_test.go000066400000000000000000000035501406627623100150310ustar00rootroot00000000000000package ssh import ( "bytes" "io/ioutil" "net" "strconv" "strings" "testing" gossh "golang.org/x/crypto/ssh" ) var sampleServerResponse = []byte("Hello world") func sampleSocketServer() net.Listener { l := newLocalListener() go func() { conn, err := l.Accept() if err != nil { return } conn.Write(sampleServerResponse) conn.Close() }() return l } func newTestSessionWithForwarding(t *testing.T, forwardingEnabled bool) (net.Listener, *gossh.Client, func()) { l := sampleSocketServer() _, client, cleanup := newTestSession(t, &Server{ Handler: func(s Session) {}, LocalPortForwardingCallback: func(ctx Context, destinationHost string, destinationPort uint32) bool { addr := net.JoinHostPort(destinationHost, strconv.FormatInt(int64(destinationPort), 10)) if addr != l.Addr().String() { panic("unexpected destinationHost: " + addr) } return forwardingEnabled }, }, nil) return l, client, func() { cleanup() l.Close() } } func TestLocalPortForwardingWorks(t *testing.T) { t.Parallel() l, client, cleanup := newTestSessionWithForwarding(t, true) defer cleanup() conn, err := client.Dial("tcp", l.Addr().String()) if err != nil { t.Fatalf("Error connecting to %v: %v", l.Addr().String(), err) } result, err := ioutil.ReadAll(conn) if err != nil { t.Fatal(err) } if !bytes.Equal(result, sampleServerResponse) { t.Fatalf("result = %#v; want %#v", result, sampleServerResponse) } } func TestLocalPortForwardingRespectsCallback(t *testing.T) { t.Parallel() l, client, cleanup := newTestSessionWithForwarding(t, false) defer cleanup() _, err := client.Dial("tcp", l.Addr().String()) if err == nil { t.Fatalf("Expected error connecting to %v but it succeeded", l.Addr().String()) } if !strings.Contains(err.Error(), "port forwarding is disabled") { t.Fatalf("Expected permission error but got %#v", err) } } ssh-0.3.3/util.go000066400000000000000000000024511406627623100136270ustar00rootroot00000000000000package 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 } ssh-0.3.3/wrap.go000066400000000000000000000021001406627623100136120ustar00rootroot00000000000000package 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) }