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-rw-r--r--cmd/puppeth/ssh.go195
1 files changed, 195 insertions, 0 deletions
diff --git a/cmd/puppeth/ssh.go b/cmd/puppeth/ssh.go
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+++ b/cmd/puppeth/ssh.go
@@ -0,0 +1,195 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package main
+
+import (
+ "errors"
+ "fmt"
+ "io/ioutil"
+ "net"
+ "os"
+ "os/user"
+ "path/filepath"
+ "strings"
+ "syscall"
+
+ "github.com/ethereum/go-ethereum/log"
+ "golang.org/x/crypto/ssh"
+ "golang.org/x/crypto/ssh/terminal"
+)
+
+// sshClient is a small wrapper around Go's SSH client with a few utility methods
+// implemented on top.
+type sshClient struct {
+ server string // Server name or IP without port number
+ address string // IP address of the remote server
+ client *ssh.Client
+ logger log.Logger
+}
+
+// dial establishes an SSH connection to a remote node using the current user and
+// the user's configured private RSA key.
+func dial(server string) (*sshClient, error) {
+ // Figure out a label for the server and a logger
+ label := server
+ if strings.Contains(label, ":") {
+ label = label[:strings.Index(label, ":")]
+ }
+ logger := log.New("server", label)
+ logger.Debug("Attempting to establish SSH connection")
+
+ user, err := user.Current()
+ if err != nil {
+ return nil, err
+ }
+ // Configure the supported authentication methods (private key and password)
+ var auths []ssh.AuthMethod
+
+ path := filepath.Join(user.HomeDir, ".ssh", "id_rsa")
+ if buf, err := ioutil.ReadFile(path); err != nil {
+ log.Warn("No SSH key, falling back to passwords", "path", path, "err", err)
+ } else {
+ key, err := ssh.ParsePrivateKey(buf)
+ if err != nil {
+ log.Warn("Bad SSH key, falling back to passwords", "path", path, "err", err)
+ } else {
+ auths = append(auths, ssh.PublicKeys(key))
+ }
+ }
+ auths = append(auths, ssh.PasswordCallback(func() (string, error) {
+ fmt.Printf("What's the login password for %s at %s? (won't be echoed)\n> ", user.Username, server)
+ blob, err := terminal.ReadPassword(int(syscall.Stdin))
+
+ fmt.Println()
+ return string(blob), err
+ }))
+ // Resolve the IP address of the remote server
+ addr, err := net.LookupHost(label)
+ if err != nil {
+ return nil, err
+ }
+ if len(addr) == 0 {
+ return nil, errors.New("no IPs associated with domain")
+ }
+ // Try to dial in to the remote server
+ logger.Trace("Dialing remote SSH server", "user", user.Username, "key", path)
+ if !strings.Contains(server, ":") {
+ server += ":22"
+ }
+ client, err := ssh.Dial("tcp", server, &ssh.ClientConfig{User: user.Username, Auth: auths})
+ if err != nil {
+ return nil, err
+ }
+ // Connection established, return our utility wrapper
+ c := &sshClient{
+ server: label,
+ address: addr[0],
+ client: client,
+ logger: logger,
+ }
+ if err := c.init(); err != nil {
+ client.Close()
+ return nil, err
+ }
+ return c, nil
+}
+
+// init runs some initialization commands on the remote server to ensure it's
+// capable of acting as puppeth target.
+func (client *sshClient) init() error {
+ client.logger.Debug("Verifying if docker is available")
+ if out, err := client.Run("docker version"); err != nil {
+ if len(out) == 0 {
+ return err
+ }
+ return fmt.Errorf("docker configured incorrectly: %s", out)
+ }
+ client.logger.Debug("Verifying if docker-compose is available")
+ if out, err := client.Run("docker-compose version"); err != nil {
+ if len(out) == 0 {
+ return err
+ }
+ return fmt.Errorf("docker-compose configured incorrectly: %s", out)
+ }
+ return nil
+}
+
+// Close terminates the connection to an SSH server.
+func (client *sshClient) Close() error {
+ return client.client.Close()
+}
+
+// Run executes a command on the remote server and returns the combined output
+// along with any error status.
+func (client *sshClient) Run(cmd string) ([]byte, error) {
+ // Establish a single command session
+ session, err := client.client.NewSession()
+ if err != nil {
+ return nil, err
+ }
+ defer session.Close()
+
+ // Execute the command and return any output
+ client.logger.Trace("Running command on remote server", "cmd", cmd)
+ return session.CombinedOutput(cmd)
+}
+
+// Stream executes a command on the remote server and streams all outputs into
+// the local stdout and stderr streams.
+func (client *sshClient) Stream(cmd string) error {
+ // Establish a single command session
+ session, err := client.client.NewSession()
+ if err != nil {
+ return err
+ }
+ defer session.Close()
+
+ session.Stdout = os.Stdout
+ session.Stderr = os.Stderr
+
+ // Execute the command and return any output
+ client.logger.Trace("Streaming command on remote server", "cmd", cmd)
+ return session.Run(cmd)
+}
+
+// Upload copied the set of files to a remote server via SCP, creating any non-
+// existing folder in te mean time.
+func (client *sshClient) Upload(files map[string][]byte) ([]byte, error) {
+ // Establish a single command session
+ session, err := client.client.NewSession()
+ if err != nil {
+ return nil, err
+ }
+ defer session.Close()
+
+ // Create a goroutine that streams the SCP content
+ go func() {
+ out, _ := session.StdinPipe()
+ defer out.Close()
+
+ for file, content := range files {
+ client.logger.Trace("Uploading file to server", "file", file, "bytes", len(content))
+
+ fmt.Fprintln(out, "D0755", 0, filepath.Dir(file)) // Ensure the folder exists
+ fmt.Fprintln(out, "C0644", len(content), filepath.Base(file)) // Create the actual file
+ out.Write(content) // Stream the data content
+ fmt.Fprint(out, "\x00") // Transfer end with \x00
+ fmt.Fprintln(out, "E") // Leave directory (simpler)
+ }
+ }()
+ return session.CombinedOutput("/usr/bin/scp -v -tr ./")
+}