From 13e582349cdd02be00b8e344161feed7fa1970a0 Mon Sep 17 00:00:00 2001
From: cellarspoon <cellarspoon@riseup.net>
Date: Wed, 19 Jan 2022 13:28:57 +0100
Subject: [PATCH] fix: correctly override with ~/.ssh/config if failing to
 connect

---
 pkg/ssh/ssh.go                         | 33 +++++++++++++++-----------
 pkg/upstream/commandconn/connection.go |  1 +
 2 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/pkg/ssh/ssh.go b/pkg/ssh/ssh.go
index 49ceb24f..d9ad4147 100644
--- a/pkg/ssh/ssh.go
+++ b/pkg/ssh/ssh.go
@@ -325,7 +325,7 @@ func connect(username, host, port string, authMethod ssh.AuthMethod, timeout tim
 	conn, err = net.DialTimeout("tcp", hostnameAndPort, timeout)
 	if err != nil {
 		logrus.Debugf("tcp dialing %s failed, trying via ~/.ssh/config", hostnameAndPort)
-		hostConfig, err := GetHostConfig(host, username, port)
+		hostConfig, err := GetHostConfig(host, username, port, true)
 		if err != nil {
 			return nil, err
 		}
@@ -452,7 +452,7 @@ func GetContextConnDetails(serverName string) (*dockerSSHPkg.Spec, error) {
 		}
 	}
 
-	hostConfig, err := GetHostConfig(serverName, "", "")
+	hostConfig, err := GetHostConfig(serverName, "", "", false)
 	if err != nil {
 		return &dockerSSHPkg.Spec{}, err
 	}
@@ -472,30 +472,36 @@ func GetContextConnDetails(serverName string) (*dockerSSHPkg.Spec, error) {
 }
 
 // GetHostConfig retrieves a ~/.ssh/config config for a host.
-func GetHostConfig(hostname, username, port string) (HostConfig, error) {
+func GetHostConfig(hostname, username, port string, override bool) (HostConfig, error) {
 	var hostConfig HostConfig
 
-	if hostname == "" {
-		if hostname = ssh_config.Get(hostname, "Hostname"); hostname == "" {
-			logrus.Debugf("no hostname found in SSH config, assuming %s", hostname)
+	if hostname == "" || override {
+		if sshHost := ssh_config.Get(hostname, "Hostname"); sshHost != "" {
+			hostname = sshHost
 		}
 	}
 
-	if username == "" {
-		if username = ssh_config.Get(hostname, "User"); username == "" {
+	if username == "" || override {
+		if sshUser := ssh_config.Get(hostname, "User"); sshUser != "" {
+			username = sshUser
+		} else {
 			systemUser, err := user.Current()
 			if err != nil {
 				return hostConfig, err
 			}
-			logrus.Debugf("no username found in SSH config or passed on command-line, assuming %s", username)
 			username = systemUser.Username
 		}
 	}
 
-	if port == "" {
-		if port = ssh_config.Get(hostname, "Port"); port == "" {
-			logrus.Debugf("no port found in SSH config or passed on command-line, assuming 22")
-			port = "22"
+	if port == "" || override {
+		if sshPort := ssh_config.Get(hostname, "Port"); sshPort != "" {
+			// skip override probably correct port with dummy default value from
+			// ssh_config which is 22. only when the original port number is empty
+			// should we try this default. this might not cover all cases
+			// unfortunately.
+			if port != "" && sshPort != "22" {
+				port = sshPort
+			}
 		}
 	}
 
@@ -507,7 +513,6 @@ func GetHostConfig(hostname, username, port string) (HostConfig, error) {
 		}
 		hostConfig.IdentityFile = idf
 	} else {
-		logrus.Debugf("no identity file found in SSH config for %s", hostname)
 		hostConfig.IdentityFile = ""
 	}
 
diff --git a/pkg/upstream/commandconn/connection.go b/pkg/upstream/commandconn/connection.go
index 2554248e..94ce8905 100644
--- a/pkg/upstream/commandconn/connection.go
+++ b/pkg/upstream/commandconn/connection.go
@@ -44,6 +44,7 @@ func getConnectionHelper(daemonURL string, sshFlags []string) (*connhelper.Conne
 			ctxConnDetails.Host,
 			ctxConnDetails.User,
 			ctxConnDetails.Port,
+			false,
 		)
 		if err != nil {
 			return nil, err