Shell out to SSH client for an ssh connection

Signed-off-by: aiordache <anca.iordache@docker.com>

docker/api/client.py

@@ -11,7 +11,7 @@ from .. import auth
 from ..constants import (DEFAULT_NUM_POOLS, DEFAULT_NUM_POOLS_SSH,
                          DEFAULT_TIMEOUT_SECONDS, DEFAULT_USER_AGENT,
                          IS_WINDOWS_PLATFORM, MINIMUM_DOCKER_API_VERSION,
-                         STREAM_HEADER_SIZE_BYTES)
+                         STREAM_HEADER_SIZE_BYTES, DEFAULT_SSH_CLIENT)
 from ..errors import (DockerException, InvalidVersion, TLSParameterError,
                       create_api_error_from_http_exception)
 from ..tls import TLSConfig
@@ -161,7 +161,8 @@ class APIClient(
         elif base_url.startswith('ssh://'):
             try:
                 self._custom_adapter = SSHHTTPAdapter(
-                    base_url, timeout, pool_connections=num_pools
+                    base_url, timeout, pool_connections=num_pools,
+                    shell_out=DEFAULT_SSH_CLIENT
                 )
             except NameError:
                 raise DockerException(

docker/constants.py

@@ -40,3 +40,5 @@ DEFAULT_DATA_CHUNK_SIZE = 1024 * 2048
 
 DEFAULT_SWARM_ADDR_POOL = ['10.0.0.0/8']
 DEFAULT_SWARM_SUBNET_SIZE = 24
+
+DEFAULT_SSH_CLIENT = True

docker/transport/sshconn.py

@@ -3,6 +3,8 @@ import requests.adapters
 import six
 import logging
 import os
+import socket
+import subprocess
 
 from docker.transport.basehttpadapter import BaseHTTPAdapter
 from .. import constants
@@ -20,30 +22,117 @@ except ImportError:
 RecentlyUsedContainer = urllib3._collections.RecentlyUsedContainer
 
 
+def create_paramiko_client(base_url):
+    logging.getLogger("paramiko").setLevel(logging.WARNING)
+    ssh_client = paramiko.SSHClient()
+    base_url = six.moves.urllib_parse.urlparse(base_url)
+    ssh_params = {
+        "hostname": base_url.hostname,
+        "port": base_url.port,
+        "username": base_url.username
+        }
+    ssh_config_file = os.path.expanduser("~/.ssh/config")
+    if os.path.exists(ssh_config_file):
+        conf = paramiko.SSHConfig()
+        with open(ssh_config_file) as f:
+            conf.parse(f)
+        host_config = conf.lookup(base_url.hostname)
+        ssh_conf = host_config
+        if 'proxycommand' in host_config:
+            ssh_params["sock"] = paramiko.ProxyCommand(
+                ssh_conf['proxycommand']
+            )
+        if 'hostname' in host_config:
+            ssh_params['hostname'] = host_config['hostname']
+        if 'identityfile' in host_config:
+            ssh_params['key_filename'] = host_config['identityfile']
+        if base_url.port is None and 'port' in host_config:
+            ssh_params['port'] = ssh_conf['port']
+        if base_url.username is None and 'user' in host_config:
+            ssh_params['username'] = ssh_conf['user']
+
+    ssh_client.load_system_host_keys()
+    ssh_client.set_missing_host_key_policy(paramiko.WarningPolicy())
+    return ssh_client
+
+
+class SSHSocket(socket.socket):
+    def __init__(self, host):
+        super(SSHSocket, self).__init__(
+            socket.AF_INET, socket.SOCK_STREAM)
+        self.host = host
+        self.proc = None
+
+    def connect(self, **kwargs):
+        args = [
+            'ssh',
+            self.host,
+            'docker system dial-stdio'
+        ]
+        self.proc = subprocess.Popen(
+            ' '.join(args),
+            shell=True,
+            stdout=subprocess.PIPE,
+            stdin=subprocess.PIPE)
+
+    def sendall(self, msg):
+        if not self.proc or self.proc.stdin.closed:
+            raise Exception('SSH subprocess not initiated.'
+                            'connect() must be called first.')
+        self.proc.stdin.write(msg)
+        self.proc.stdin.flush()
+
+    def recv(self):
+        if not self.proc:
+            raise Exception('SSH subprocess not initiated.'
+                            'connect() must be called first.')
+        return self.proc.stdout.read()
+
+    def makefile(self, mode):
+        return self.proc.stdout
+
+    def close(self):
+        if not self.proc:
+            return
+        self.proc.stdin.write(b'\n\n')
+        self.proc.stdin.flush()
+        self.proc.terminate()
+
+
 class SSHConnection(httplib.HTTPConnection, object):
-    def __init__(self, ssh_transport, timeout=60):
+    def __init__(self, ssh_transport=None, timeout=60, host=None):
         super(SSHConnection, self).__init__(
             'localhost', timeout=timeout
         )
         self.ssh_transport = ssh_transport
         self.timeout = timeout
+        self.host = host
 
     def connect(self):
-        sock = self.ssh_transport.open_session()
-        sock.settimeout(self.timeout)
-        sock.exec_command('docker system dial-stdio')
+        if self.ssh_transport:
+            sock = self.ssh_transport.open_session()
+            sock.settimeout(self.timeout)
+            sock.exec_command('docker system dial-stdio')
+        else:
+            sock = SSHSocket(self.host)
+            sock.settimeout(self.timeout)
+            sock.connect()
+
         self.sock = sock
 
 
 class SSHConnectionPool(urllib3.connectionpool.HTTPConnectionPool):
     scheme = 'ssh'
 
-    def __init__(self, ssh_client, timeout=60, maxsize=10):
+    def __init__(self, ssh_client=None, timeout=60, maxsize=10, host=None):
         super(SSHConnectionPool, self).__init__(
             'localhost', timeout=timeout, maxsize=maxsize
         )
-        self.ssh_transport = ssh_client.get_transport()
+        self.ssh_transport = None
+        if ssh_client:
+            self.ssh_transport = ssh_client.get_transport()
         self.timeout = timeout
+        self.host = host
 
     def _new_conn(self):
         return SSHConnection(self.ssh_transport, self.timeout)
@@ -78,39 +167,14 @@ class SSHHTTPAdapter(BaseHTTPAdapter):
     ]
 
     def __init__(self, base_url, timeout=60,
-                 pool_connections=constants.DEFAULT_NUM_POOLS):
-        logging.getLogger("paramiko").setLevel(logging.WARNING)
-        self.ssh_client = paramiko.SSHClient()
-        base_url = six.moves.urllib_parse.urlparse(base_url)
-        self.ssh_params = {
-            "hostname": base_url.hostname,
-            "port": base_url.port,
-            "username": base_url.username
-            }
-        ssh_config_file = os.path.expanduser("~/.ssh/config")
-        if os.path.exists(ssh_config_file):
-            conf = paramiko.SSHConfig()
-            with open(ssh_config_file) as f:
-                conf.parse(f)
-            host_config = conf.lookup(base_url.hostname)
-            self.ssh_conf = host_config
-            if 'proxycommand' in host_config:
-                self.ssh_params["sock"] = paramiko.ProxyCommand(
-                    self.ssh_conf['proxycommand']
-                )
-            if 'hostname' in host_config:
-                self.ssh_params['hostname'] = host_config['hostname']
-            if 'identityfile' in host_config:
-                self.ssh_params['key_filename'] = host_config['identityfile']
-            if base_url.port is None and 'port' in host_config:
-                self.ssh_params['port'] = self.ssh_conf['port']
-            if base_url.username is None and 'user' in host_config:
-                self.ssh_params['username'] = self.ssh_conf['user']
+                 pool_connections=constants.DEFAULT_NUM_POOLS,
+                 shell_out=True):
+        self.ssh_client = None
+        if not shell_out:
+            self.ssh_client = create_paramiko_client(base_url)
+            self._connect()
 
-        self.ssh_client.load_system_host_keys()
-        self.ssh_client.set_missing_host_key_policy(paramiko.WarningPolicy())
-
-        self._connect()
+        self.host = base_url
         self.timeout = timeout
         self.pools = RecentlyUsedContainer(
             pool_connections, dispose_func=lambda p: p.close()
@@ -118,7 +182,8 @@ class SSHHTTPAdapter(BaseHTTPAdapter):
         super(SSHHTTPAdapter, self).__init__()
 
     def _connect(self):
-        self.ssh_client.connect(**self.ssh_params)
+        if self.ssh_client:
+            self.ssh_client.connect(**self.ssh_params)
 
     def get_connection(self, url, proxies=None):
         with self.pools.lock:
@@ -127,11 +192,13 @@ class SSHHTTPAdapter(BaseHTTPAdapter):
                 return pool
 
             # Connection is closed try a reconnect
-            if not self.ssh_client.get_transport():
+            if self.ssh_client and not self.ssh_client.get_transport():
                 self._connect()
 
             pool = SSHConnectionPool(
-                self.ssh_client, self.timeout
+                ssh_client=self.ssh_client,
+                timeout=self.timeout,
+                host=self.host
             )
             self.pools[url] = pool
 
@@ -139,4 +206,5 @@ class SSHHTTPAdapter(BaseHTTPAdapter):
 
     def close(self):
         super(SSHHTTPAdapter, self).close()
-        self.ssh_client.close()
+        if self.ssh_client:
+            self.ssh_client.close()