Merge pull request #58 from jjohnson42/sshkey

SSH known hosts handling

confluent_server/confluent/config/attributes.py

@@ -278,4 +278,8 @@ node = {
         'description':  ('Fingerprint of the TLS certificate recognized as'
                          'belonging to the hardware manager of the server'),
     },
+    'pubkeys.ssh': {
+        'description': ('Fingerprint of the SSH key of the OS running on the '
+                        'system.'),
+    },
 }

confluent_server/confluent/exceptions.py

@@ -77,10 +77,12 @@ class PubkeyInvalid(ConfluentException):
     apierrorcode = 502
     apierrorstr = '502 - Invalid certificate or key on target'
 
-    def __init__(self, text, certificate, fingerprint, attribname):
+    def __init__(self, text, certificate, fingerprint, attribname, event):
         super(PubkeyInvalid, self).__init__(self, text)
         self.fingerprint = fingerprint
-        bodydata = {'fingerprint': fingerprint,
+        bodydata = {'message': text,
+                    'event': event,
+                    'fingerprint': fingerprint,
                     'fingerprintfield': attribname,
                     'certificate': base64.b64encode(certificate)}
         self.errorbody = json.dumps(bodydata)

confluent_server/confluent/plugins/shell/ssh.py

@@ -14,17 +14,50 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-__author__ = 'jjohnson2'
 
 # This plugin provides an ssh implementation comforming to the 'console'
 # specification.  consoleserver or shellserver would be equally likely
 # to use this.
 
+import confluent.exceptions as cexc
 import confluent.interface.console as conapi
+import confluent.log as log
 import eventlet
+import hashlib
 paramiko = eventlet.import_patched('paramiko')
 
 
+class HostKeyHandler(paramiko.client.MissingHostKeyPolicy):
+
+    def __init__(self, configmanager, node):
+        self.cfm = configmanager
+        self.node = node
+
+    def missing_host_key(self, client, hostname, key):
+        fingerprint = 'sha512$' + hashlib.sha512(key.asbytes()).hexdigest()
+        cfg = self.cfm.get_node_attributes(
+                self.node, ('pubkeys.ssh', 'pubkeys.addpolicy'))
+        if 'pubkeys.ssh' not in cfg[self.node]:
+            if ('pubkeys.addpolicy' in cfg[self.node] and
+                    cfg[self.node]['pubkeys.addpolicy'] and
+                    cfg[self.node]['pubkeys.addpolicy']['value'] == 'manual'):
+                raise cexc.PubkeyInvalid('New ssh key detected',
+                                         key.asbytes(), fingerprint,
+                                         'pubkeys.ssh', 'newkey')
+            auditlog = log.Logger('audit')
+            auditlog.log({'node': self.node, 'event': 'sshautoadd',
+                          'fingerprint': fingerprint})
+            self.cfm.set_node_attributes(
+                    {self.node: {'pubkeys.ssh': fingerprint}})
+            return True
+        elif cfg[self.node]['pubkeys.ssh']['value'] == fingerprint:
+            return True
+        raise cexc.PubkeyInvalid(
+            'Mismatched SSH host key detected', key.asbytes(), fingerprint,
+                'pubkeys.ssh', 'mismatch'
+        )
+
+
 class SshShell(conapi.Console):
 
     def __init__(self, node, config, username='', password=''):
@@ -33,7 +66,7 @@ class SshShell(conapi.Console):
         self.nodeconfig = config
         self.username = username
         self.password = password
-        self.inputmode = 0 # 0 = username, 1 = password...
+        self.inputmode = 0  # 0 = username, 1 = password...
 
     def recvdata(self):
         while self.connected:
@@ -45,7 +78,7 @@ class SshShell(conapi.Console):
 
     def connect(self, callback):
         # for now, we just use the nodename as the presumptive ssh destination
-        #TODO(jjohnson2): use a 'nodeipget' utility function for architectures
+        # TODO(jjohnson2): use a 'nodeipget' utility function for architectures
         # that would rather not use the nodename as anything but an opaque
         # identifier
         self.datacallback = callback
@@ -58,7 +91,8 @@ class SshShell(conapi.Console):
 
     def logon(self):
         self.ssh = paramiko.SSHClient()
-        self.ssh.set_missing_host_key_policy(paramiko.client.AutoAddPolicy())
+        self.ssh.set_missing_host_key_policy(
+                HostKeyHandler(self.nodeconfig, self.node))
         try:
             self.ssh.connect(self.node, username=self.username,
                              password=self.password, allow_agent=False,

confluent_server/confluent/util.py

@@ -82,7 +82,7 @@ class TLSCertVerifier(object):
                 # manually
                 raise cexc.PubkeyInvalid('New certificate detected',
                                          certificate, fingerprint,
-                                         self.fieldname)
+                                         self.fieldname, 'newkey')
             # since the policy is not manual, go ahead and add new key
             # after logging to audit log
             auditlog = log.Logger('audit')
@@ -93,6 +93,6 @@ class TLSCertVerifier(object):
             return True
         elif storedprint[self.node][self.fieldname]['value'] == fingerprint:
             return True
-        raise cexc.PubKeyInvalid(
+        raise cexc.PubkeyInvalid(
             'Mismatched certificate detected', certificate, fingerprint,
-            self.fieldname)
+            self.fieldname, 'mismatch')