X-Git-Url: https://code.grnet.gr/git/ganeti-local/blobdiff_plain/1d544ba38373096575207fceef815e11dc0bc985..e310b019ad43467bc243d886d50597de5d81c27a:/lib/ssh.py

diff --git a/lib/ssh.py b/lib/ssh.py
index 6f32e56..7d314e2 100644
--- a/lib/ssh.py
+++ b/lib/ssh.py
@@ -33,25 +33,6 @@ from ganeti import constants
 from ganeti import ssconf
 
 
-KNOWN_HOSTS_OPTS = [
-  "-oGlobalKnownHostsFile=%s" % constants.SSH_KNOWN_HOSTS_FILE,
-  "-oUserKnownHostsFile=/dev/null",
-  ]
-
-# Note: BATCH_MODE conflicts with ASK_KEY
-BATCH_MODE_OPTS = [
-  "-oBatchMode=yes",
-  "-oEscapeChar=none",
-  "-oStrictHostKeyChecking=yes",
-  ]
-
-ASK_KEY_OPTS = [
-  "-oEscapeChar=none",
-  "-oHashKnownHosts=no",
-  "-oStrictHostKeyChecking=ask",
-  ]
-
-
 def GetUserFiles(user, mkdir=False):
   """Return the paths of a user's ssh files.
 
@@ -97,11 +78,42 @@ class SshRunner:
     else:
       self.sstore = sstore
 
-  def _GetHostKeyAliasOption(self):
-    return "-oHostKeyAlias=%s" % self.sstore.GetClusterName()
+  def _BuildSshOptions(self, batch, ask_key, use_cluster_key,
+                       strict_host_check):
+    options = [
+      "-oEscapeChar=none",
+      "-oHashKnownHosts=no",
+      "-oGlobalKnownHostsFile=%s" % constants.SSH_KNOWN_HOSTS_FILE,
+      "-oUserKnownHostsFile=/dev/null",
+      ]
+
+    if use_cluster_key:
+      options.append("-oHostKeyAlias=%s" % self.sstore.GetClusterName())
+
+    # TODO: Too many boolean options, maybe convert them to more descriptive
+    # constants.
+
+    # Note: ask_key conflicts with batch mode
+    if batch:
+      if ask_key:
+        raise errors.ProgrammerError("SSH call requested conflicting options")
+
+      options.append("-oBatchMode=yes")
+
+      if strict_host_check:
+        options.append("-oStrictHostKeyChecking=yes")
+      else:
+        options.append("-oStrictHostKeyChecking=no")
+
+    elif ask_key:
+      options.extend([
+        "-oStrictHostKeyChecking=ask",
+        ])
+
+    return options
 
   def BuildCmd(self, hostname, user, command, batch=True, ask_key=False,
-               tty=False):
+               tty=False, use_cluster_key=True, strict_host_check=True):
     """Build an ssh command to execute a command on a remote node.
 
     Args:
@@ -111,46 +123,35 @@ class SshRunner:
       batch: if true, ssh will run in batch mode with no prompting
       ask_key: if true, ssh will run with StrictHostKeyChecking=ask, so that
                we can connect to an unknown host (not valid in batch mode)
+      use_cluster_key: Whether to expect and use the cluster-global SSH key
+      strict_host_check: Whether to check the host's SSH key at all
 
     Returns:
       The ssh call to run 'command' on the remote host.
 
     """
     argv = [constants.SSH, "-q"]
-    argv.extend(KNOWN_HOSTS_OPTS)
-    argv.append(self._GetHostKeyAliasOption())
-    if batch:
-      # if we are in batch mode, we can't ask the key
-      if ask_key:
-        raise errors.ProgrammerError("SSH call requested conflicting options")
-      argv.extend(BATCH_MODE_OPTS)
-    elif ask_key:
-      argv.extend(ASK_KEY_OPTS)
+    argv.extend(self._BuildSshOptions(batch, ask_key, use_cluster_key,
+                                      strict_host_check))
     if tty:
       argv.append("-t")
     argv.extend(["%s@%s" % (user, hostname), command])
     return argv
 
-  def Run(self, hostname, user, command, batch=True, ask_key=False):
+  def Run(self, *args, **kwargs):
     """Runs a command on a remote node.
 
     This method has the same return value as `utils.RunCmd()`, which it
     uses to launch ssh.
 
     Args:
-      hostname: the target host, string
-      user: user to auth as
-      command: the command
-      batch: if true, ssh will run in batch mode with no prompting
-      ask_key: if true, ssh will run with StrictHostKeyChecking=ask, so that
-               we can connect to an unknown host (not valid in batch mode)
+      See SshRunner.BuildCmd.
 
     Returns:
       `utils.RunResult` like `utils.RunCmd()`
 
     """
-    return utils.RunCmd(self.BuildCmd(hostname, user, command, batch=batch,
-                                      ask_key=ask_key))
+    return utils.RunCmd(self.BuildCmd(*args, **kwargs))
 
   def CopyFileToNode(self, node, filename):
     """Copy a file to another node with scp.
@@ -172,9 +173,7 @@ class SshRunner:
       return False
 
     command = [constants.SCP, "-q", "-p"]
-    command.extend(KNOWN_HOSTS_OPTS)
-    command.extend(BATCH_MODE_OPTS)
-    command.append(self._GetHostKeyAliasOption())
+    command.extend(self._BuildSshOptions(True, False, True, True))
     command.append(filename)
     command.append("%s:%s" % (node, filename))