schnutibox/vendor/github.com/helloyi/go-sshclient/sshclient.go

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// Package sshclient implements an SSH client.
package sshclient
import (
"bytes"
"errors"
"fmt"
"io"
"io/ioutil"
"net"
"os"
"golang.org/x/crypto/ssh"
)
type remoteScriptType byte
type remoteShellType byte
const (
cmdLine remoteScriptType = iota
rawScript
scriptFile
interactiveShell remoteShellType = iota
nonInteractiveShell
)
// A Client implements an SSH client that supports running commands and scripts remotely.
type Client struct {
client *ssh.Client
}
// DialWithPasswd starts a client connection to the given SSH server with passwd authmethod.
func DialWithPasswd(addr, user, passwd string) (*Client, error) {
config := &ssh.ClientConfig{
User: user,
Auth: []ssh.AuthMethod{
ssh.Password(passwd),
},
HostKeyCallback: ssh.HostKeyCallback(func(hostname string, remote net.Addr, key ssh.PublicKey) error { return nil }),
}
return Dial("tcp", addr, config)
}
// DialWithKey starts a client connection to the given SSH server with key authmethod.
func DialWithKey(addr, user, keyfile string) (*Client, error) {
key, err := ioutil.ReadFile(keyfile)
if err != nil {
return nil, err
}
signer, err := ssh.ParsePrivateKey(key)
if err != nil {
return nil, err
}
config := &ssh.ClientConfig{
User: user,
Auth: []ssh.AuthMethod{
ssh.PublicKeys(signer),
},
HostKeyCallback: ssh.HostKeyCallback(func(hostname string, remote net.Addr, key ssh.PublicKey) error { return nil }),
}
return Dial("tcp", addr, config)
}
// DialWithKeyWithPassphrase same as DialWithKey but with a passphrase to decrypt the private key
func DialWithKeyWithPassphrase(addr, user, keyfile string, passphrase string) (*Client, error) {
key, err := ioutil.ReadFile(keyfile)
if err != nil {
return nil, err
}
signer, err := ssh.ParsePrivateKeyWithPassphrase(key, []byte(passphrase))
if err != nil {
return nil, err
}
config := &ssh.ClientConfig{
User: user,
Auth: []ssh.AuthMethod{
ssh.PublicKeys(signer),
},
HostKeyCallback: ssh.HostKeyCallback(func(hostname string, remote net.Addr, key ssh.PublicKey) error { return nil }),
}
return Dial("tcp", addr, config)
}
// Dial starts a client connection to the given SSH server.
// This wraps ssh.Dial.
func Dial(network, addr string, config *ssh.ClientConfig) (*Client, error) {
client, err := ssh.Dial(network, addr, config)
if err != nil {
return nil, err
}
return &Client{
client: client,
}, nil
}
// Close closes the underlying client network connection.
func (c *Client) Close() error {
return c.client.Close()
}
// Cmd creates a RemoteScript that can run the command on the client. The cmd string is split on newlines and each line is executed separately.
func (c *Client) Cmd(cmd string) *RemoteScript {
return &RemoteScript{
_type: cmdLine,
client: c.client,
script: bytes.NewBufferString(cmd + "\n"),
}
}
// Script creates a RemoteScript that can run the script on the client.
func (c *Client) Script(script string) *RemoteScript {
return &RemoteScript{
_type: rawScript,
client: c.client,
script: bytes.NewBufferString(script + "\n"),
}
}
// ScriptFile creates a RemoteScript that can read a local script file and run it remotely on the client.
func (c *Client) ScriptFile(fname string) *RemoteScript {
return &RemoteScript{
_type: scriptFile,
client: c.client,
scriptFile: fname,
}
}
// A RemoteScript represents script that can be run remotely.
type RemoteScript struct {
client *ssh.Client
_type remoteScriptType
script *bytes.Buffer
scriptFile string
err error
stdout io.Writer
stderr io.Writer
}
// Run runs the script on the client.
//
// The returned error is nil if the command runs, has no problems
// copying stdin, stdout, and stderr, and exits with a zero exit
// status.
func (rs *RemoteScript) Run() error {
if rs.err != nil {
fmt.Println(rs.err)
return rs.err
}
if rs._type == cmdLine {
return rs.runCmds()
} else if rs._type == rawScript {
return rs.runScript()
} else if rs._type == scriptFile {
return rs.runScriptFile()
} else {
return errors.New("Not supported RemoteScript type")
}
}
// Output runs the script on the client and returns its standard output.
func (rs *RemoteScript) Output() ([]byte, error) {
if rs.stdout != nil {
return nil, errors.New("Stdout already set")
}
var out bytes.Buffer
rs.stdout = &out
err := rs.Run()
return out.Bytes(), err
}
// SmartOutput runs the script on the client. On success, its standard ouput is returned. On error, its standard error is returned.
func (rs *RemoteScript) SmartOutput() ([]byte, error) {
if rs.stdout != nil {
return nil, errors.New("Stdout already set")
}
if rs.stderr != nil {
return nil, errors.New("Stderr already set")
}
var (
stdout bytes.Buffer
stderr bytes.Buffer
)
rs.stdout = &stdout
rs.stderr = &stderr
err := rs.Run()
if err != nil {
return stderr.Bytes(), err
}
return stdout.Bytes(), err
}
// Cmd appends a command to the RemoteScript.
func (rs *RemoteScript) Cmd(cmd string) *RemoteScript {
_, err := rs.script.WriteString(cmd + "\n")
if err != nil {
rs.err = err
}
return rs
}
// SetStdio specifies where its standard output and error data will be written.
func (rs *RemoteScript) SetStdio(stdout, stderr io.Writer) *RemoteScript {
rs.stdout = stdout
rs.stderr = stderr
return rs
}
func (rs *RemoteScript) runCmd(cmd string) error {
session, err := rs.client.NewSession()
if err != nil {
return err
}
defer session.Close()
session.Stdout = rs.stdout
session.Stderr = rs.stderr
if err := session.Run(cmd); err != nil {
return err
}
return nil
}
func (rs *RemoteScript) runCmds() error {
for {
statment, err := rs.script.ReadString('\n')
if err == io.EOF {
break
}
if err != nil {
return err
}
if err := rs.runCmd(statment); err != nil {
return err
}
}
return nil
}
func (rs *RemoteScript) runScript() error {
session, err := rs.client.NewSession()
if err != nil {
return err
}
session.Stdin = rs.script
session.Stdout = rs.stdout
session.Stderr = rs.stderr
if err := session.Shell(); err != nil {
return err
}
if err := session.Wait(); err != nil {
return err
}
return nil
}
func (rs *RemoteScript) runScriptFile() error {
var buffer bytes.Buffer
file, err := os.Open(rs.scriptFile)
if err != nil {
return err
}
defer file.Close()
_, err = io.Copy(&buffer, file)
if err != nil {
return err
}
rs.script = &buffer
return rs.runScript()
}
// A RemoteShell represents a login shell on the client.
type RemoteShell struct {
client *ssh.Client
requestPty bool
terminalConfig *TerminalConfig
stdin io.Reader
stdout io.Writer
stderr io.Writer
}
// A TerminalConfig represents the configuration for an interactive shell session.
type TerminalConfig struct {
Term string
Height int
Weight int
Modes ssh.TerminalModes
}
// Terminal create a interactive shell on client.
func (c *Client) Terminal(config *TerminalConfig) *RemoteShell {
return &RemoteShell{
client: c.client,
terminalConfig: config,
requestPty: true,
}
}
// Shell create a noninteractive shell on client.
func (c *Client) Shell() *RemoteShell {
return &RemoteShell{
client: c.client,
requestPty: false,
}
}
// SetStdio specifies where the its standard output and error data will be written.
func (rs *RemoteShell) SetStdio(stdin io.Reader, stdout, stderr io.Writer) *RemoteShell {
rs.stdin = stdin
rs.stdout = stdout
rs.stderr = stderr
return rs
}
// Start starts a remote shell on client.
func (rs *RemoteShell) Start() error {
session, err := rs.client.NewSession()
if err != nil {
return err
}
defer session.Close()
if rs.stdin == nil {
session.Stdin = os.Stdin
} else {
session.Stdin = rs.stdin
}
if rs.stdout == nil {
session.Stdout = os.Stdout
} else {
session.Stdout = rs.stdout
}
if rs.stderr == nil {
session.Stderr = os.Stderr
} else {
session.Stderr = rs.stderr
}
if rs.requestPty {
tc := rs.terminalConfig
if tc == nil {
tc = &TerminalConfig{
Term: "xterm",
Height: 40,
Weight: 80,
}
}
if err := session.RequestPty(tc.Term, tc.Height, tc.Weight, tc.Modes); err != nil {
return err
}
}
if err := session.Shell(); err != nil {
return err
}
if err := session.Wait(); err != nil {
return err
}
return nil
}