summary refs log tree commit diff
path: root/synapse/http/matrixfederationclient.py
blob: bf1aa29502717480aab910c0cc7e9204700b2949 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
# -*- coding: utf-8 -*-
# Copyright 2014-2016 OpenMarket Ltd
# Copyright 2018 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import cgi
import logging
import random
import sys
import urllib

from six import string_types
from six.moves.urllib import parse as urlparse

from canonicaljson import encode_canonical_json, json
from prometheus_client import Counter
from signedjson.sign import sign_json

from twisted.internet import defer, protocol, reactor
from twisted.internet.error import DNSLookupError
from twisted.web._newclient import ResponseDone
from twisted.web.client import Agent, HTTPConnectionPool, readBody
from twisted.web.http_headers import Headers

import synapse.metrics
import synapse.util.retryutils
from synapse.api.errors import (
    Codes,
    FederationDeniedError,
    HttpResponseException,
    SynapseError,
)
from synapse.http import cancelled_to_request_timed_out_error
from synapse.http.endpoint import matrix_federation_endpoint
from synapse.util import logcontext
from synapse.util.async import add_timeout_to_deferred
from synapse.util.logcontext import make_deferred_yieldable

logger = logging.getLogger(__name__)
outbound_logger = logging.getLogger("synapse.http.outbound")

outgoing_requests_counter = Counter("synapse_http_matrixfederationclient_requests",
                                    "", ["method"])
incoming_responses_counter = Counter("synapse_http_matrixfederationclient_responses",
                                     "", ["method", "code"])


MAX_LONG_RETRIES = 10
MAX_SHORT_RETRIES = 3


class MatrixFederationEndpointFactory(object):
    def __init__(self, hs):
        self.tls_server_context_factory = hs.tls_server_context_factory

    def endpointForURI(self, uri):
        destination = uri.netloc

        return matrix_federation_endpoint(
            reactor, destination, timeout=10,
            ssl_context_factory=self.tls_server_context_factory
        )


class MatrixFederationHttpClient(object):
    """HTTP client used to talk to other homeservers over the federation
    protocol. Send client certificates and signs requests.

    Attributes:
        agent (twisted.web.client.Agent): The twisted Agent used to send the
            requests.
    """

    def __init__(self, hs):
        self.hs = hs
        self.signing_key = hs.config.signing_key[0]
        self.server_name = hs.hostname
        pool = HTTPConnectionPool(reactor)
        pool.maxPersistentPerHost = 5
        pool.cachedConnectionTimeout = 2 * 60
        self.agent = Agent.usingEndpointFactory(
            reactor, MatrixFederationEndpointFactory(hs), pool=pool
        )
        self.clock = hs.get_clock()
        self._store = hs.get_datastore()
        self.version_string = hs.version_string
        self._next_id = 1

    def _create_url(self, destination, path_bytes, param_bytes, query_bytes):
        return urlparse.urlunparse(
            ("matrix", destination, path_bytes, param_bytes, query_bytes, "")
        )

    @defer.inlineCallbacks
    def _request(self, destination, method, path,
                 body_callback, headers_dict={}, param_bytes=b"",
                 query_bytes=b"", retry_on_dns_fail=True,
                 timeout=None, long_retries=False,
                 ignore_backoff=False,
                 backoff_on_404=False):
        """ Creates and sends a request to the given server
        Args:
            destination (str): The remote server to send the HTTP request to.
            method (str): HTTP method
            path (str): The HTTP path
            ignore_backoff (bool): true to ignore the historical backoff data
                and try the request anyway.
            backoff_on_404 (bool): Back off if we get a 404

        Returns:
            Deferred: resolves with the http response object on success.

            Fails with ``HTTPRequestException``: if we get an HTTP response
                code >= 300.

            Fails with ``NotRetryingDestination`` if we are not yet ready
                to retry this server.

            Fails with ``FederationDeniedError`` if this destination
                is not on our federation whitelist

            (May also fail with plenty of other Exceptions for things like DNS
                failures, connection failures, SSL failures.)
        """
        if (
            self.hs.config.federation_domain_whitelist and
            destination not in self.hs.config.federation_domain_whitelist
        ):
            raise FederationDeniedError(destination)

        limiter = yield synapse.util.retryutils.get_retry_limiter(
            destination,
            self.clock,
            self._store,
            backoff_on_404=backoff_on_404,
            ignore_backoff=ignore_backoff,
        )

        destination = destination.encode("ascii")
        path_bytes = path.encode("ascii")
        with limiter:
            headers_dict[b"User-Agent"] = [self.version_string]
            headers_dict[b"Host"] = [destination]

            url_bytes = self._create_url(
                destination, path_bytes, param_bytes, query_bytes
            )

            txn_id = "%s-O-%s" % (method, self._next_id)
            self._next_id = (self._next_id + 1) % (sys.maxint - 1)

            outbound_logger.info(
                "{%s} [%s] Sending request: %s %s",
                txn_id, destination, method, url_bytes
            )

            # XXX: Would be much nicer to retry only at the transaction-layer
            # (once we have reliable transactions in place)
            if long_retries:
                retries_left = MAX_LONG_RETRIES
            else:
                retries_left = MAX_SHORT_RETRIES

            http_url_bytes = urlparse.urlunparse(
                ("", "", path_bytes, param_bytes, query_bytes, "")
            )

            log_result = None
            try:
                while True:
                    producer = None
                    if body_callback:
                        producer = body_callback(method, http_url_bytes, headers_dict)

                    try:
                        request_deferred = self.agent.request(
                            method,
                            url_bytes,
                            Headers(headers_dict),
                            producer
                        )
                        add_timeout_to_deferred(
                            request_deferred,
                            timeout / 1000. if timeout else 60,
                            self.hs.get_reactor(),
                            cancelled_to_request_timed_out_error,
                        )
                        response = yield make_deferred_yieldable(
                            request_deferred,
                        )

                        log_result = "%d %s" % (response.code, response.phrase,)
                        break
                    except Exception as e:
                        if not retry_on_dns_fail and isinstance(e, DNSLookupError):
                            logger.warn(
                                "DNS Lookup failed to %s with %s",
                                destination,
                                e
                            )
                            log_result = "DNS Lookup failed to %s with %s" % (
                                destination, e
                            )
                            raise

                        logger.warn(
                            "{%s} Sending request failed to %s: %s %s: %s",
                            txn_id,
                            destination,
                            method,
                            url_bytes,
                            _flatten_response_never_received(e),
                        )

                        log_result = _flatten_response_never_received(e)

                        if retries_left and not timeout:
                            if long_retries:
                                delay = 4 ** (MAX_LONG_RETRIES + 1 - retries_left)
                                delay = min(delay, 60)
                                delay *= random.uniform(0.8, 1.4)
                            else:
                                delay = 0.5 * 2 ** (MAX_SHORT_RETRIES - retries_left)
                                delay = min(delay, 2)
                                delay *= random.uniform(0.8, 1.4)

                            yield self.clock.sleep(delay)
                            retries_left -= 1
                        else:
                            raise
            finally:
                outbound_logger.info(
                    "{%s} [%s] Result: %s",
                    txn_id,
                    destination,
                    log_result,
                )

            if 200 <= response.code < 300:
                pass
            else:
                # :'(
                # Update transactions table?
                with logcontext.PreserveLoggingContext():
                    body = yield readBody(response)
                raise HttpResponseException(
                    response.code, response.phrase, body
                )

            defer.returnValue(response)

    def sign_request(self, destination, method, url_bytes, headers_dict,
                     content=None, destination_is=None):
        """
        Signs a request by adding an Authorization header to headers_dict
        Args:
            destination (bytes|None): The desination home server of the request.
                May be None if the destination is an identity server, in which case
                destination_is must be non-None.
            method (bytes): The HTTP method of the request
            url_bytes (bytes): The URI path of the request
            headers_dict (dict): Dictionary of request headers to append to
            content (bytes): The body of the request
            destination_is (bytes): As 'destination', but if the destination is an
                identity server

        Returns:
            None
        """
        request = {
            "method": method,
            "uri": url_bytes,
            "origin": self.server_name,
        }

        if destination is not None:
            request["destination"] = destination

        if destination_is is not None:
            request["destination_is"] = destination_is

        if content is not None:
            request["content"] = content

        request = sign_json(request, self.server_name, self.signing_key)

        auth_headers = []

        for key, sig in request["signatures"][self.server_name].items():
            auth_headers.append(bytes(
                "X-Matrix origin=%s,key=\"%s\",sig=\"%s\"" % (
                    self.server_name, key, sig,
                )
            ))

        headers_dict[b"Authorization"] = auth_headers

    @defer.inlineCallbacks
    def put_json(self, destination, path, args={}, data={},
                 json_data_callback=None,
                 long_retries=False, timeout=None,
                 ignore_backoff=False,
                 backoff_on_404=False):
        """ Sends the specifed json data using PUT

        Args:
            destination (str): The remote server to send the HTTP request
                to.
            path (str): The HTTP path.
            args (dict): query params
            data (dict): A dict containing the data that will be used as
                the request body. This will be encoded as JSON.
            json_data_callback (callable): A callable returning the dict to
                use as the request body.
            long_retries (bool): A boolean that indicates whether we should
                retry for a short or long time.
            timeout(int): How long to try (in ms) the destination for before
                giving up. None indicates no timeout.
            ignore_backoff (bool): true to ignore the historical backoff data
                and try the request anyway.
            backoff_on_404 (bool): True if we should count a 404 response as
                a failure of the server (and should therefore back off future
                requests)

        Returns:
            Deferred: Succeeds when we get a 2xx HTTP response. The result
            will be the decoded JSON body.

            Fails with ``HTTPRequestException`` if we get an HTTP response
            code >= 300.

            Fails with ``NotRetryingDestination`` if we are not yet ready
            to retry this server.

            Fails with ``FederationDeniedError`` if this destination
            is not on our federation whitelist
        """

        if not json_data_callback:
            def json_data_callback():
                return data

        def body_callback(method, url_bytes, headers_dict):
            json_data = json_data_callback()
            self.sign_request(
                destination, method, url_bytes, headers_dict, json_data
            )
            producer = _JsonProducer(json_data)
            return producer

        response = yield self._request(
            destination,
            "PUT",
            path,
            body_callback=body_callback,
            headers_dict={"Content-Type": ["application/json"]},
            query_bytes=encode_query_args(args),
            long_retries=long_retries,
            timeout=timeout,
            ignore_backoff=ignore_backoff,
            backoff_on_404=backoff_on_404,
        )

        if 200 <= response.code < 300:
            # We need to update the transactions table to say it was sent?
            check_content_type_is_json(response.headers)

        with logcontext.PreserveLoggingContext():
            body = yield readBody(response)
        defer.returnValue(json.loads(body))

    @defer.inlineCallbacks
    def post_json(self, destination, path, data={}, long_retries=False,
                  timeout=None, ignore_backoff=False, args={}):
        """ Sends the specifed json data using POST

        Args:
            destination (str): The remote server to send the HTTP request
                to.
            path (str): The HTTP path.
            data (dict): A dict containing the data that will be used as
                the request body. This will be encoded as JSON.
            long_retries (bool): A boolean that indicates whether we should
                retry for a short or long time.
            timeout(int): How long to try (in ms) the destination for before
                giving up. None indicates no timeout.
            ignore_backoff (bool): true to ignore the historical backoff data and
                try the request anyway.
            args (dict): query params
        Returns:
            Deferred: Succeeds when we get a 2xx HTTP response. The result
            will be the decoded JSON body.

            Fails with ``HTTPRequestException`` if we get an HTTP response
            code >= 300.

            Fails with ``NotRetryingDestination`` if we are not yet ready
            to retry this server.

            Fails with ``FederationDeniedError`` if this destination
            is not on our federation whitelist
        """

        def body_callback(method, url_bytes, headers_dict):
            self.sign_request(
                destination, method, url_bytes, headers_dict, data
            )
            return _JsonProducer(data)

        response = yield self._request(
            destination,
            "POST",
            path,
            query_bytes=encode_query_args(args),
            body_callback=body_callback,
            headers_dict={"Content-Type": ["application/json"]},
            long_retries=long_retries,
            timeout=timeout,
            ignore_backoff=ignore_backoff,
        )

        if 200 <= response.code < 300:
            # We need to update the transactions table to say it was sent?
            check_content_type_is_json(response.headers)

        with logcontext.PreserveLoggingContext():
            body = yield readBody(response)

        defer.returnValue(json.loads(body))

    @defer.inlineCallbacks
    def get_json(self, destination, path, args={}, retry_on_dns_fail=True,
                 timeout=None, ignore_backoff=False):
        """ GETs some json from the given host homeserver and path

        Args:
            destination (str): The remote server to send the HTTP request
                to.
            path (str): The HTTP path.
            args (dict): A dictionary used to create query strings, defaults to
                None.
            timeout (int): How long to try (in ms) the destination for before
                giving up. None indicates no timeout and that the request will
                be retried.
            ignore_backoff (bool): true to ignore the historical backoff data
                and try the request anyway.
        Returns:
            Deferred: Succeeds when we get a 2xx HTTP response. The result
            will be the decoded JSON body.

            Fails with ``HTTPRequestException`` if we get an HTTP response
            code >= 300.

            Fails with ``NotRetryingDestination`` if we are not yet ready
            to retry this server.

            Fails with ``FederationDeniedError`` if this destination
            is not on our federation whitelist
        """
        logger.debug("get_json args: %s", args)

        logger.debug("Query bytes: %s Retry DNS: %s", args, retry_on_dns_fail)

        def body_callback(method, url_bytes, headers_dict):
            self.sign_request(destination, method, url_bytes, headers_dict)
            return None

        response = yield self._request(
            destination,
            "GET",
            path,
            query_bytes=encode_query_args(args),
            body_callback=body_callback,
            retry_on_dns_fail=retry_on_dns_fail,
            timeout=timeout,
            ignore_backoff=ignore_backoff,
        )

        if 200 <= response.code < 300:
            # We need to update the transactions table to say it was sent?
            check_content_type_is_json(response.headers)

        with logcontext.PreserveLoggingContext():
            body = yield readBody(response)

        defer.returnValue(json.loads(body))

    @defer.inlineCallbacks
    def delete_json(self, destination, path, long_retries=False,
                    timeout=None, ignore_backoff=False, args={}):
        """Send a DELETE request to the remote expecting some json response

        Args:
            destination (str): The remote server to send the HTTP request
                to.
            path (str): The HTTP path.
            long_retries (bool): A boolean that indicates whether we should
                retry for a short or long time.
            timeout(int): How long to try (in ms) the destination for before
                giving up. None indicates no timeout.
            ignore_backoff (bool): true to ignore the historical backoff data and
                try the request anyway.
        Returns:
            Deferred: Succeeds when we get a 2xx HTTP response. The result
            will be the decoded JSON body.

            Fails with ``HTTPRequestException`` if we get an HTTP response
            code >= 300.

            Fails with ``NotRetryingDestination`` if we are not yet ready
            to retry this server.

            Fails with ``FederationDeniedError`` if this destination
            is not on our federation whitelist
        """

        response = yield self._request(
            destination,
            "DELETE",
            path,
            query_bytes=encode_query_args(args),
            headers_dict={"Content-Type": ["application/json"]},
            long_retries=long_retries,
            timeout=timeout,
            ignore_backoff=ignore_backoff,
        )

        if 200 <= response.code < 300:
            # We need to update the transactions table to say it was sent?
            check_content_type_is_json(response.headers)

        with logcontext.PreserveLoggingContext():
            body = yield readBody(response)

        defer.returnValue(json.loads(body))

    @defer.inlineCallbacks
    def get_file(self, destination, path, output_stream, args={},
                 retry_on_dns_fail=True, max_size=None,
                 ignore_backoff=False):
        """GETs a file from a given homeserver
        Args:
            destination (str): The remote server to send the HTTP request to.
            path (str): The HTTP path to GET.
            output_stream (file): File to write the response body to.
            args (dict): Optional dictionary used to create the query string.
            ignore_backoff (bool): true to ignore the historical backoff data
                and try the request anyway.
        Returns:
            Deferred: resolves with an (int,dict) tuple of the file length and
            a dict of the response headers.

            Fails with ``HTTPRequestException`` if we get an HTTP response code
            >= 300

            Fails with ``NotRetryingDestination`` if we are not yet ready
            to retry this server.

            Fails with ``FederationDeniedError`` if this destination
            is not on our federation whitelist
        """

        encoded_args = {}
        for k, vs in args.items():
            if isinstance(vs, string_types):
                vs = [vs]
            encoded_args[k] = [v.encode("UTF-8") for v in vs]

        query_bytes = urllib.urlencode(encoded_args, True)
        logger.debug("Query bytes: %s Retry DNS: %s", query_bytes, retry_on_dns_fail)

        def body_callback(method, url_bytes, headers_dict):
            self.sign_request(destination, method, url_bytes, headers_dict)
            return None

        response = yield self._request(
            destination,
            "GET",
            path,
            query_bytes=query_bytes,
            body_callback=body_callback,
            retry_on_dns_fail=retry_on_dns_fail,
            ignore_backoff=ignore_backoff,
        )

        headers = dict(response.headers.getAllRawHeaders())

        try:
            with logcontext.PreserveLoggingContext():
                length = yield _readBodyToFile(
                    response, output_stream, max_size
                )
        except Exception:
            logger.exception("Failed to download body")
            raise

        defer.returnValue((length, headers))


class _ReadBodyToFileProtocol(protocol.Protocol):
    def __init__(self, stream, deferred, max_size):
        self.stream = stream
        self.deferred = deferred
        self.length = 0
        self.max_size = max_size

    def dataReceived(self, data):
        self.stream.write(data)
        self.length += len(data)
        if self.max_size is not None and self.length >= self.max_size:
            self.deferred.errback(SynapseError(
                502,
                "Requested file is too large > %r bytes" % (self.max_size,),
                Codes.TOO_LARGE,
            ))
            self.deferred = defer.Deferred()
            self.transport.loseConnection()

    def connectionLost(self, reason):
        if reason.check(ResponseDone):
            self.deferred.callback(self.length)
        else:
            self.deferred.errback(reason)


def _readBodyToFile(response, stream, max_size):
    d = defer.Deferred()
    response.deliverBody(_ReadBodyToFileProtocol(stream, d, max_size))
    return d


class _JsonProducer(object):
    """ Used by the twisted http client to create the HTTP body from json
    """
    def __init__(self, jsn):
        self.reset(jsn)

    def reset(self, jsn):
        self.body = encode_canonical_json(jsn)
        self.length = len(self.body)

    def startProducing(self, consumer):
        consumer.write(self.body)
        return defer.succeed(None)

    def pauseProducing(self):
        pass

    def stopProducing(self):
        pass

    def resumeProducing(self):
        pass


def _flatten_response_never_received(e):
    if hasattr(e, "reasons"):
        reasons = ", ".join(
            _flatten_response_never_received(f.value)
            for f in e.reasons
        )

        return "%s:[%s]" % (type(e).__name__, reasons)
    else:
        return repr(e)


def check_content_type_is_json(headers):
    """
    Check that a set of HTTP headers have a Content-Type header, and that it
    is application/json.

    Args:
        headers (twisted.web.http_headers.Headers): headers to check

    Raises:
        RuntimeError if the

    """
    c_type = headers.getRawHeaders(b"Content-Type")
    if c_type is None:
        raise RuntimeError(
            "No Content-Type header"
        )

    c_type = c_type[0]  # only the first header
    val, options = cgi.parse_header(c_type)
    if val != "application/json":
        raise RuntimeError(
            "Content-Type not application/json: was '%s'" % c_type
        )


def encode_query_args(args):
    encoded_args = {}
    for k, vs in args.items():
        if isinstance(vs, string_types):
            vs = [vs]
        encoded_args[k] = [v.encode("UTF-8") for v in vs]

    query_bytes = urllib.urlencode(encoded_args, True)

    return query_bytes