diff --git a/master/buildbot/changes/p4poller.py b/master/buildbot/changes/p4poller.py
index 65a94af67b9..1db6d2319b8 100644
--- a/master/buildbot/changes/p4poller.py
+++ b/master/buildbot/changes/p4poller.py
@@ -21,22 +21,64 @@
 import dateutil
 import exceptions
 import os
+import os.path
 import re
 
 from twisted.internet import defer
+from twisted.internet import protocol
+from twisted.internet import reactor
 from twisted.internet import utils
 from twisted.python import log
 
+from buildbot import config
 from buildbot import util
 from buildbot.changes import base
 
 
+debug_logging = False
+
+
 class P4PollerError(Exception):
 
     """Something went wrong with the poll. This is used as a distinctive
     exception type so that unit tests can detect and ignore it."""
 
 
+class TicketLoginProtocol(protocol.ProcessProtocol):
+
+    """ Twisted process protocol to run `p4 login` and enter our password
+        in the stdin."""
+
+    def __init__(self, stdin, p4base):
+        self.deferred = defer.Deferred()
+        self.stdin = stdin
+        self.stdout = ''
+        self.stderr = ''
+        self.p4base = p4base
+
+    def connectionMade(self):
+        if self.stdin:
+            if debug_logging:
+                log.msg("P4Poller: entering password for %s: %s" % (self.p4base, self.stdin))
+            self.transport.write(self.stdin)
+        self.transport.closeStdin()
+
+    def processEnded(self, reason):
+        if debug_logging:
+            log.msg("P4Poller: login process finished for %s: %s" % (self.p4base, reason.value.exitCode))
+        self.deferred.callback(reason.value.exitCode)
+
+    def outReceived(self, data):
+        if debug_logging:
+            log.msg("P4Poller: login stdout for %s: %s" % (self.p4base, data))
+        self.stdout += data
+
+    def errReceived(self, data):
+        if debug_logging:
+            log.msg("P4Poller: login stderr for %s: %s" % (self.p4base, data))
+        self.stderr += data
+
+
 def get_simple_split(branchfile):
     """Splits the branchfile argument and assuming branch is
        the first path component in branchfile, will return
@@ -76,6 +118,7 @@ def __init__(self, p4port=None, p4user=None, p4passwd=None,
                  split_file=lambda branchfile: (None, branchfile),
                  pollInterval=60 * 10, histmax=None, pollinterval=-2,
                  encoding='utf8', project=None, name=None,
+                 use_tickets=False, ticket_login_interval=60 * 60 * 24,
                  server_tz=None, pollAtLaunch=False):
 
         # for backward compatibility; the parameter used to be spelled with 'i'
@@ -92,6 +135,9 @@ def __init__(self, p4port=None, p4user=None, p4passwd=None,
         if project is None:
             project = ''
 
+        if use_tickets and not p4passwd:
+            config.error("You need to provide a P4 password to use ticket authentication")
+
         self.p4port = p4port
         self.p4user = p4user
         self.p4passwd = p4passwd
@@ -100,14 +146,19 @@ def __init__(self, p4port=None, p4user=None, p4passwd=None,
         self.split_file = split_file
         self.encoding = encoding
         self.project = util.ascii2unicode(project)
+        self.use_tickets = use_tickets
+        self.ticket_login_interval = ticket_login_interval
         self.server_tz = server_tz
 
+        self._ticket_passwd = None
+        self._ticket_login_counter = 0
+
     def describe(self):
         return "p4source %s %s" % (self.p4port, self.p4base)
 
     def poll(self):
         d = self._poll()
-        d.addErrback(log.err, 'P4 poll failed')
+        d.addErrback(log.err, 'P4 poll failed on %s, %s' % (self.p4port, self.p4base))
         return d
 
     def _get_process_output(self, args):
@@ -115,15 +166,52 @@ def _get_process_output(self, args):
         d = utils.getProcessOutput(self.p4bin, args, env)
         return d
 
+    def _acquireTicket(self, protocol):
+        command = [self.p4bin, ]
+        if self.p4port:
+            command.extend(['-p', self.p4port])
+        if self.p4user:
+            command.extend(['-u', self.p4user])
+        command.extend(['login', '-p'])
+        command = [c.encode('utf-8') for c in command]
+
+        reactor.spawnProcess(protocol, self.p4bin, command, env=os.environ)
+
+    def _parseTicketPassword(self, text):
+        lines = text.split("\n")
+        if len(lines) < 2:
+            return None
+        return lines[1].strip()
+
+    def _getPasswd(self):
+        if self.use_tickets:
+            return self._ticket_passwd
+        return self.p4passwd
+
     @defer.inlineCallbacks
     def _poll(self):
+        if self.use_tickets:
+            self._ticket_login_counter -= 1
+            if self._ticket_login_counter <= 0:
+                # Re-acquire the ticket and reset the counter.
+                log.msg("P4Poller: (re)acquiring P4 ticket for %s..." % self.p4base)
+                protocol = TicketLoginProtocol(self.p4passwd + "\n", self.p4base)
+                self._acquireTicket(protocol)
+                yield protocol.deferred
+
+                self._ticket_passwd = self._parseTicketPassword(protocol.stdout)
+                self._ticket_login_counter = max(self.ticket_login_interval / self.pollInterval, 1)
+                if debug_logging:
+                    log.msg("P4Poller: got ticket password: %s" % self._ticket_passwd)
+                    log.msg("P4Poller: next ticket acquisition in %d polls" % self._ticket_login_counter)
+
         args = []
         if self.p4port:
             args.extend(['-p', self.p4port])
         if self.p4user:
             args.extend(['-u', self.p4user])
         if self.p4passwd:
-            args.extend(['-P', self.p4passwd])
+            args.extend(['-P', self._getPasswd()])
         args.extend(['changes'])
         if self.last_change is not None:
             args.extend(['%s...@%d,now' % (self.p4base, self.last_change + 1)])
@@ -159,7 +247,7 @@ def _poll(self):
             if self.p4user:
                 args.extend(['-u', self.p4user])
             if self.p4passwd:
-                args.extend(['-P', self.p4passwd])
+                args.extend(['-P', self._getPasswd()])
             args.extend(['describe', '-s', str(num)])
             result = yield self._get_process_output(args)
 
@@ -169,7 +257,7 @@ def _poll(self):
             except exceptions.UnicodeError, ex:
                 log.msg("P4Poller: couldn't decode changelist description: %s" % ex.encoding)
                 log.msg("P4Poller: in object: %s" % ex.object)
-                log.err("P4Poller: poll failed")
+                log.err("P4Poller: poll failed on %s, %s" % (self.p4port, self.p4base))
                 raise
 
             lines = result.split('\n')
diff --git a/master/buildbot/steps/source/p4.py b/master/buildbot/steps/source/p4.py
index 13e48ef7b3e..690e9fd941b 100644
--- a/master/buildbot/steps/source/p4.py
+++ b/master/buildbot/steps/source/p4.py
@@ -46,7 +46,7 @@ class P4(Source):
 
     name = 'p4'
 
-    renderables = ['p4base', 'p4client', 'p4viewspec', 'p4branch']
+    renderables = ['mode', 'p4base', 'p4client', 'p4viewspec', 'p4branch']
     possible_modes = ('incremental', 'full')
 
     def __init__(self, mode='incremental',
@@ -58,6 +58,7 @@ def __init__(self, mode='incremental',
                  p4client_spec_options='allwrite rmdir',
                  p4extra_args=None,
                  p4bin='p4',
+                 use_tickets=False,
                  **kwargs):
         self.method = method
         self.mode = mode
@@ -74,11 +75,12 @@ def __init__(self, mode='incremental',
         self.p4client = p4client
         self.p4client_spec_options = p4client_spec_options
         self.p4extra_args = p4extra_args
+        self.use_tickets = use_tickets
 
         Source.__init__(self, **kwargs)
 
-        if self.mode not in self.possible_modes:
-            config.error("mode %s is not one of %s" % (self.mode, self.possible_modes))
+        if self.mode not in self.possible_modes and not interfaces.IRenderable.providedBy(self.mode):
+            config.error("mode %s is not an IRenderable, or one of %s" % (self.mode, self.possible_modes))
 
         if not p4viewspec and p4base is None:
             config.error("You must provide p4base or p4viewspec")
@@ -117,6 +119,9 @@ def checkInstall(p4Installed):
             return 0
         d.addCallback(checkInstall)
 
+        if self.use_tickets and self.p4passwd:
+            d.addCallback(self._acquireTicket)
+
         if self.mode == 'full':
             d.addCallback(self.full)
         elif self.mode == 'incremental':
@@ -197,11 +202,12 @@ def _buildVCCommand(self, doCommand):
             command.extend(['-p', self.p4port])
         if self.p4user:
             command.extend(['-u', self.p4user])
-        if self.p4passwd:
+        if not self.use_tickets and self.p4passwd:
             # Need to find out if there's a way to obfuscate this
             command.extend(['-P', self.p4passwd])
         if self.p4client:
             command.extend(['-c', self.p4client])
+
         # Only add the extra arguments for the `sync` command.
         if doCommand[0] == 'sync' and self.p4extra_args:
             command.extend(self.p4extra_args)
@@ -216,6 +222,7 @@ def _dovccmd(self, command, collectStdout=False, initialStdin=None):
 
         if debug_logging:
             log.msg("P4:_dovccmd():workdir->%s" % self.workdir)
+
         cmd = buildstep.RemoteShellCommand(self.workdir, command,
                                            env=self.env,
                                            logEnviron=self.logEnviron,
@@ -313,6 +320,15 @@ def _createClientSpec(self):
         mo = re.search(r'Client (\S+) (.+)$', stdout, re.M)
         defer.returnValue(mo and (mo.group(2) == 'saved.' or mo.group(2) == 'not changed.'))
 
+    @defer.inlineCallbacks
+    def _acquireTicket(self, _):
+        if debug_logging:
+            log.msg("P4:acquireTicket()")
+
+        # TODO: check first if the ticket is still valid?
+        initialStdin = self.p4passwd + "\n"
+        yield self._dovccmd(['login'], initialStdin=initialStdin)
+
     def parseGotRevision(self, _):
         command = self._buildVCCommand(['changes', '-m1', '#have'])
 
diff --git a/master/buildbot/test/unit/test_changes_p4poller.py b/master/buildbot/test/unit/test_changes_p4poller.py
index 13a300766cf..0f2b90e55d5 100644
--- a/master/buildbot/test/unit/test_changes_p4poller.py
+++ b/master/buildbot/test/unit/test_changes_p4poller.py
@@ -21,56 +21,59 @@
 from buildbot.test.util import changesource
 from buildbot.test.util import gpo
 from buildbot.util import datetime2epoch
+from twisted.internet import error
+from twisted.internet import reactor
+from twisted.python import failure
 from twisted.trial import unittest
 
 first_p4changes = \
-"""Change 1 on 2006/04/13 by slamb@testclient 'first rev'
+    """Change 1 on 2006/04/13 by slamb@testclient 'first rev'
 """
 
 second_p4changes = \
-"""Change 3 on 2006/04/13 by bob@testclient 'short desc truncated'
+    """Change 3 on 2006/04/13 by bob@testclient 'short desc truncated'
 Change 2 on 2006/04/13 by slamb@testclient 'bar'
 """
 
 third_p4changes = \
-"""Change 5 on 2006/04/13 by mpatel@testclient 'first rev'
+    """Change 5 on 2006/04/13 by mpatel@testclient 'first rev'
 """
 
 change_4_log = \
-"""Change 4 by mpatel@testclient on 2006/04/13 21:55:39
+    """Change 4 by mpatel@testclient on 2006/04/13 21:55:39
 
 \tshort desc truncated because this is a long description.
 """
 
 change_3_log = \
-u"""Change 3 by bob@testclient on 2006/04/13 21:51:39
+    u"""Change 3 by bob@testclient on 2006/04/13 21:51:39
 
 \tshort desc truncated because this is a long description.
     ASDF-GUI-P3-\u2018Upgrade Icon\u2019 disappears sometimes.
 """
 
 change_2_log = \
-"""Change 2 by slamb@testclient on 2006/04/13 21:46:23
+    """Change 2 by slamb@testclient on 2006/04/13 21:46:23
 
 \tcreation
 """
 
 p4change = {
     3: change_3_log +
-"""Affected files ...
+    """Affected files ...
 
 ... //depot/myproject/branch_b/branch_b_file#1 add
 ... //depot/myproject/branch_b/whatbranch#1 branch
 ... //depot/myproject/branch_c/whatbranch#1 branch
 """,
     2: change_2_log +
-"""Affected files ...
+    """Affected files ...
 
 ... //depot/myproject/trunk/whatbranch#1 add
 ... //depot/otherproject/trunk/something#1 add
 """,
     5: change_4_log +
-"""Affected files ...
+    """Affected files ...
 
 ... //depot/myproject/branch_b/branch_b_file#1 add
 ... //depot/myproject/branch_b#75 edit
@@ -250,6 +253,47 @@ def check(_):
             self.assertAllCommandsRan()
         return d
 
+    def test_acquire_ticket_auth(self):
+        self.attachChangeSource(
+            P4Source(p4port=None, p4user=None, p4passwd='pass',
+                     p4base='//depot/myproject/',
+                     split_file=lambda x: x.split('/', 1),
+                     use_tickets=True))
+        self.expectCommands(
+            gpo.Expect('p4', '-P', 'TICKET_ID_GOES_HERE',
+                       'changes', '-m', '1', '//depot/myproject/...').stdout(first_p4changes)
+        )
+
+        class FakeTransport:
+
+            def __init__(self):
+                self.msg = None
+
+            def write(self, msg):
+                self.msg = msg
+
+            def closeStdin(self):
+                pass
+
+        transport = FakeTransport()
+
+        def spawnProcess(pp, cmd, argv, env):  # p4poller uses only those arguments at the moment
+            self.assertEqual([cmd, argv],
+                             ['p4', ['p4', 'login', '-p']])
+            pp.makeConnection(transport)
+            self.assertEqual('pass\n', transport.msg)
+            pp.outReceived('Enter password:\nTICKET_ID_GOES_HERE\n')
+            so = error.ProcessDone(None)
+            pp.processEnded(failure.Failure(so))
+        self.patch(reactor, 'spawnProcess', spawnProcess)
+
+        d = self.changesource.poll()
+
+        def check_ticket_passwd(_):
+            self.assertEquals(self.changesource._ticket_passwd, 'TICKET_ID_GOES_HERE')
+        d.addCallback(check_ticket_passwd)
+        return d
+
     def test_poll_split_file(self):
         """Make sure split file works on branch only changes"""
         self.attachChangeSource(
diff --git a/master/buildbot/test/unit/test_steps_source_p4.py b/master/buildbot/test/unit/test_steps_source_p4.py
index 00349610cd8..71e1aee0eda 100644
--- a/master/buildbot/test/unit/test_steps_source_p4.py
+++ b/master/buildbot/test/unit/test_steps_source_p4.py
@@ -742,3 +742,64 @@ def test_slave_connection_lost(self):
         self.expectOutcome(result=RETRY,
                            status_text=["update", "exception", "slave", "lost"])
         return self.runStep()
+
+    def test_ticket_auth(self):
+        self.setupStep(P4(p4port='localhost:12000',
+                          p4base='//depot', p4branch='trunk',
+                          p4user='user', p4client='p4_client1',
+                          p4passwd='pass', use_tickets=True))
+
+        root_dir = '/home/user/workspace/wkdir'
+        if _is_windows:
+            root_dir = r'C:\Users\username\Workspace\wkdir'
+        client_spec = textwrap.dedent('''\
+        Client: p4_client1
+
+        Owner: user
+
+        Description:
+        \tCreated by user
+
+        Root:\t%s
+
+        Options:\tallwrite rmdir
+
+        LineEnd:\tlocal
+
+        View:
+        \t//depot/trunk/... //p4_client1/...
+        ''' % root_dir)
+
+        self.expectCommands(
+            ExpectShell(workdir='wkdir', command=['p4', '-V'])
+            + 0,
+
+            # This is the extra step that gets run when using tickets,
+            # and the password is not passed anymore after that.
+            ExpectShell(workdir='wkdir',
+                        command=['p4', '-p', 'localhost:12000', '-u', 'user',
+                                       '-c', 'p4_client1',
+                                       'login'],
+                        initialStdin='pass\n')
+            + 0,
+
+            ExpectShell(workdir='wkdir',
+                        command=['p4', '-p', 'localhost:12000', '-u', 'user',
+                                       '-c', 'p4_client1',
+                                       'client', '-i'],
+                        initialStdin=client_spec)
+            + 0,
+            ExpectShell(workdir='wkdir',
+                        command=(['p4', '-p', 'localhost:12000', '-u', 'user',
+                                  '-c', 'p4_client1', 'sync']))
+            + 0,
+            ExpectShell(workdir='wkdir',
+                        command=['p4', '-p', 'localhost:12000', '-u', 'user',
+                                       '-c', 'p4_client1',
+                                       'changes', '-m1', '#have'])
+            + ExpectShell.log('stdio',
+                              stdout="Change 100 on 2013/03/21 by user@machine \'duh\'")
+            + 0,
+        )
+        self.expectOutcome(result=SUCCESS, status_text=["update"])
+        return self.runStep()
diff --git a/master/docs/manual/cfg-buildsteps.rst b/master/docs/manual/cfg-buildsteps.rst
index f5b124e63a7..c3295063a15 100644
--- a/master/docs/manual/cfg-buildsteps.rst
+++ b/master/docs/manual/cfg-buildsteps.rst
@@ -869,6 +869,9 @@ you will receive a configuration error exception.
 
         P4(p4extra_args=['-Zproxyload'], ...)
 
+``use_tickets``
+    Set to ``True`` to use ticket-based authentication, instead of passwords (but
+    you still need to specify ``p4passwd``).
 
 
 .. index:: double: Gerrit integration; Repo Build Step
diff --git a/master/docs/manual/cfg-changesources.rst b/master/docs/manual/cfg-changesources.rst
index d3a25f4bfda..cc38fd43543 100644
--- a/master/docs/manual/cfg-changesources.rst
+++ b/master/docs/manual/cfg-changesources.rst
@@ -621,6 +621,14 @@ depot for changes. It accepts the following arguments:
     (e.g: ``Europe/Stockholm``) in case it's in a different timezone than the
     buildbot master.
 
+``use_tickets``
+    Set to ``True`` to use ticket-based authentication, instead of passwords (but
+    you still need to specify ``p4passwd``).
+
+``ticket_login_interval``
+    How often to get a new ticket, in seconds, when ``use_tickets`` is enabled.
+    Defaults to 86400 (24 hours).
+
 Example
 +++++++
 
diff --git a/master/docs/relnotes/index.rst b/master/docs/relnotes/index.rst
index 9eeb4d9aacd..c5bcebe043d 100644
--- a/master/docs/relnotes/index.rst
+++ b/master/docs/relnotes/index.rst
@@ -106,6 +106,8 @@ Master
 Features
 ~~~~~~~~
 
+* Both the P4 source step and P4 change source support ticket-based authentication.
+
 Fixes
 ~~~~~