2 files changed, 25 insertions, 5 deletions

diff --git a/systest b/systest
index 1d5d673..577adc1 100755
--- a/systest
+++ b/systest
@@ -32,6 +32,8 @@ class SystemTest(cliapp.Application):
         self.settings.integer(['ssh-port'], 'target ssh port', default=22)
         self.settings.string(['user'], 'user on target')
         self.settings.string(['user-password'], 'password for target user')
+        self.settings.string(['user-ssh-private-key'], 
+                             'user\'s private key for logging in')
 
     def process_args(self, args):
         loader = unittest.defaultTestLoader
diff --git a/systest.py b/systest.py
index bdcb3b6..4bfbcfb 100755
--- a/systest.py
+++ b/systest.py
@@ -26,8 +26,10 @@ the hostname of the target system.
 
 
 import logging
+import os
 import re
 import subprocess
+import tempfile
 import unittest
 
 
@@ -59,16 +61,32 @@ class TestCase(unittest.TestCase):
 
     def targetcmd(self, argv, *args, **kwargs):
         '''Run command on test target.'''
-        full_argv = (['ssh', '-l', self.settings['user'], 
-                      '-p', str(self.settings['ssh-port']),
-                      self.settings['target']] + 
-                     argv)
-        returncode, out, err = self.runcmd(full_argv, *args, **kwargs)
+        
+        self.setup_known_hosts()
+
+        prefix = ['ssh', 
+                  '-l', self.settings['user'], 
+                  '-p', str(self.settings['ssh-port']),
+                  '-o', 'UserKnownHostsFile %s' % self.known_hosts,
+                 ]
+        if self.settings['user-ssh-private-key']:
+            prefix += ['-i', self.settings['user-ssh-private-key']]
+        prefix += [self.settings['target'], '--']
+
+        returncode, out, err = self.runcmd(prefix + argv, *args, **kwargs)
         if returncode:
             msg = 'target command failed: %s\n%s' % (' '.join(argv), err)
             raise AssertionError(msg)
         return out
 
+    def setup_known_hosts(self):
+        '''Setup a temporary known hosts file, and add target's key there.'''
+        
+        fd, self.known_hosts = tempfile.mkstemp()
+        out = self.hostcmd(['ssh-keyscan', self.settings['target']])
+        os.write(fd, out)
+        os.close(fd)
+
     def assertMatches(self, pat, text, msg=None):
         self.assert_(re.match(pat, text),
                      msg=('pattern %s does not match %s' % (pat, text)) or msg)