package ssh import ( "fmt" "strings" "gopkg.in/src-d/go-git.v4/plumbing/transport" "gopkg.in/src-d/go-git.v4/plumbing/transport/internal/common" "golang.org/x/crypto/ssh" ) // DefaultClient is the default SSH client. var DefaultClient = common.NewClient(&runner{}) type runner struct{} func (r *runner) Command(cmd string, ep transport.Endpoint, auth transport.AuthMethod) (common.Command, error) { c := &command{command: cmd, endpoint: ep} if auth != nil { c.setAuth(auth) } if err := c.connect(); err != nil { return nil, err } return c, nil } type command struct { *ssh.Session connected bool command string endpoint transport.Endpoint client *ssh.Client auth AuthMethod } func (c *command) setAuth(auth transport.AuthMethod) error { a, ok := auth.(AuthMethod) if !ok { return transport.ErrInvalidAuthMethod } c.auth = a return nil } func (c *command) Start() error { return c.Session.Start(endpointToCommand(c.command, c.endpoint)) } // Close closes the SSH session and connection. func (c *command) Close() error { if !c.connected { return nil } c.connected = false //XXX: If did read the full packfile, then the session might be already // closed. _ = c.Session.Close() return c.client.Close() } // connect connects to the SSH server, unless a AuthMethod was set with // SetAuth method, by default uses an auth method based on PublicKeysCallback, // it connects to a SSH agent, using the address stored in the SSH_AUTH_SOCK // environment var. func (c *command) connect() error { if c.connected { return transport.ErrAlreadyConnected } if c.auth == nil { if err := c.setAuthFromEndpoint(); err != nil { return err } } var err error c.client, err = ssh.Dial("tcp", c.getHostWithPort(), c.auth.clientConfig()) if err != nil { return err } c.Session, err = c.client.NewSession() if err != nil { _ = c.client.Close() return err } c.connected = true return nil } func (c *command) getHostWithPort() string { host := c.endpoint.Host if strings.Index(c.endpoint.Host, ":") == -1 { host += ":22" } return host } func (c *command) setAuthFromEndpoint() error { var u string if info := c.endpoint.User; info != nil { u = info.Username() } var err error c.auth, err = NewSSHAgentAuth(u) return err } func endpointToCommand(cmd string, ep transport.Endpoint) string { return fmt.Sprintf("%s '%s'", cmd, ep.Path) }