ssh: leverage proxy.Dial

This enables interacting with git remotes over SSH when behind a SOCKSv5
firewall.

Signed-off-by: Jacob Blain Christen <dweomer5@gmail.com>

2 files changed, 62 insertions, 1 deletions

diff --git a/plumbing/transport/ssh/common.go b/plumbing/transport/ssh/common.go
index e4a3d18..d320d43 100644
--- a/plumbing/transport/ssh/common.go
+++ b/plumbing/transport/ssh/common.go
@@ -2,6 +2,7 @@
 package ssh
 
 import (
+	"context"
 	"fmt"
 	"reflect"
 	"strconv"
@@ -11,6 +12,7 @@ import (
 
 	"github.com/kevinburke/ssh_config"
 	"golang.org/x/crypto/ssh"
+	"golang.org/x/net/proxy"
 )
 
 // DefaultClient is the default SSH client.
@@ -115,7 +117,7 @@ func (c *command) connect() error {
 
 	overrideConfig(c.config, config)
 
-	c.client, err = ssh.Dial("tcp", c.getHostWithPort(), config)
+	c.client, err = dial("tcp", c.getHostWithPort(), config)
 	if err != nil {
 		return err
 	}
@@ -130,6 +132,29 @@ func (c *command) connect() error {
 	return nil
 }
 
+func dial(network, addr string, config *ssh.ClientConfig) (*ssh.Client, error) {
+	var (
+		ctx    = context.Background()
+		cancel context.CancelFunc
+	)
+	if config.Timeout > 0 {
+		ctx, cancel = context.WithTimeout(ctx, config.Timeout)
+	} else {
+		ctx, cancel = context.WithCancel(ctx)
+	}
+	defer cancel()
+
+	conn, err := proxy.Dial(ctx, network, addr)
+	if err != nil {
+		return nil, err
+	}
+	c, chans, reqs, err := ssh.NewClientConn(conn, addr, config)
+	if err != nil {
+		return nil, err
+	}
+	return ssh.NewClient(c, chans, reqs), nil
+}
+
 func (c *command) getHostWithPort() string {
 	if addr, found := c.doGetHostWithPortFromSSHConfig(); found {
 		return addr
diff --git a/plumbing/transport/ssh/proxy_test.go b/plumbing/transport/ssh/proxy_test.go
new file mode 100644
index 0000000..3caf1ff
--- /dev/null
+++ b/plumbing/transport/ssh/proxy_test.go
@@ -0,0 +1,36 @@
+package ssh
+
+import (
+	"fmt"
+	"log"
+	"net"
+	"os"
+
+	"github.com/armon/go-socks5"
+	. "gopkg.in/check.v1"
+)
+
+type ProxySuite struct {
+	UploadPackSuite
+}
+
+var _ = Suite(&ProxySuite{})
+
+func (s *ProxySuite) SetUpSuite(c *C) {
+	s.UploadPackSuite.SetUpSuite(c)
+
+	l, err := net.Listen("tcp", "localhost:0")
+	c.Assert(err, IsNil)
+
+	server, err := socks5.New(&socks5.Config{})
+	c.Assert(err, IsNil)
+
+	port := l.Addr().(*net.TCPAddr).Port
+
+	err = os.Setenv("ALL_PROXY", fmt.Sprintf("socks5://localhost:%d", port))
+	c.Assert(err, IsNil)
+
+	go func() {
+		log.Fatal(server.Serve(l))
+	}()
+}