fleetctl: fixed incorrect "auth-agent-req@openssh.com" behavior

kayrus · kayrus · commit ea415adbb229 · 2016-03-17T16:56:37.000+01:00
fixes: #1425
diff --git a/ssh/ssh.go b/ssh/ssh.go
@@ -30,10 +30,14 @@ import (
 type SSHForwardingClient struct {
 	agentForwarding bool
 	*gossh.Client
+	agentForwardingEnabled bool
 }
 
 func (s *SSHForwardingClient) ForwardAgentAuthentication(session *gossh.Session) error {
-	if s.agentForwarding {
+	if s.agentForwarding && !s.agentForwardingEnabled {
+		// We are allowed to send "auth-agent-req@openssh.com" request only once per channel
+		// otherwise ssh daemon replies with the "SSH2_MSG_CHANNEL_FAILURE 100"
+		s.agentForwardingEnabled = true
 		return gosshagent.RequestAgentForwarding(session)
 	}
 	return nil
@@ -50,7 +54,7 @@ func newSSHForwardingClient(client *gossh.Client, agentForwarding bool) (*SSHFor
 		return nil, err
 	}
 
-	return &SSHForwardingClient{agentForwarding, client}, nil
+	return &SSHForwardingClient{agentForwarding, client, false}, nil
 }
 
 // makeSession initializes a gossh.Session connected to the invoking process's stdout/stderr/stdout.

Original file line number	Diff line number	Diff line change
`@@ -30,10 +30,14 @@ import (`
`30`	`30`	`type SSHForwardingClient struct {`
`31`	`31`	`agentForwarding bool`
`32`	`32`	`*gossh.Client`
	`33`	`+ agentForwardingEnabled bool`
`33`	`34`	`}`
`34`	`35`
`35`	`36`	`func (s SSHForwardingClient) ForwardAgentAuthentication(session gossh.Session) error {`
`36`		`- if s.agentForwarding {`
	`37`	`+ if s.agentForwarding && !s.agentForwardingEnabled {`
	`38`	`+ // We are allowed to send "[email protected]" request only once per channel`
	`39`	`+ // otherwise ssh daemon replies with the "SSH2_MSG_CHANNEL_FAILURE 100"`
	`40`	`+ s.agentForwardingEnabled = true`
`37`	`41`	`return gosshagent.RequestAgentForwarding(session)`
`38`	`42`	`}`
`39`	`43`	`return nil`
`@@ -50,7 +54,7 @@ func newSSHForwardingClient(client gossh.Client, agentForwarding bool) (SSHFor`
`50`	`54`	`return nil, err`
`51`	`55`	`}`
`52`	`56`
`53`		`- return &SSHForwardingClient{agentForwarding, client}, nil`
	`57`	`+ return &SSHForwardingClient{agentForwarding, client, false}, nil`
`54`	`58`	`}`
`55`	`59`
`56`	`60`	`// makeSession initializes a gossh.Session connected to the invoking process's stdout/stderr/stdout.`