summaryrefslogtreecommitdiff
path: root/src/mongo/db/keys_collection_manager.cpp
blob: 6c142de231477f825767bf25d48b2394c5e04501 (plain)
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
/**
 *    Copyright (C) 2017 MongoDB Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kDefault

#include "mongo/platform/basic.h"

#include "mongo/db/keys_collection_manager.h"

#include "mongo/db/key_generator.h"
#include "mongo/db/keys_collection_cache.h"
#include "mongo/db/keys_collection_client.h"
#include "mongo/db/logical_clock.h"
#include "mongo/db/logical_time.h"
#include "mongo/db/operation_context.h"
#include "mongo/db/server_parameters.h"
#include "mongo/db/service_context.h"
#include "mongo/stdx/memory.h"
#include "mongo/util/concurrency/idle_thread_block.h"
#include "mongo/util/fail_point_service.h"
#include "mongo/util/log.h"
#include "mongo/util/mongoutils/str.h"
#include "mongo/util/time_support.h"

namespace mongo {

const Seconds KeysCollectionManager::kKeyValidInterval{3 * 30 * 24 * 60 * 60};  // ~3 months
const std::string KeysCollectionManager::kKeyManagerPurposeString = "HMAC";

MONGO_EXPORT_STARTUP_SERVER_PARAMETER(KeysRotationIntervalSec,
                                      int,
                                      KeysCollectionManager::kKeyValidInterval.count());

namespace {

Milliseconds kDefaultRefreshWaitTime(30 * 1000);
Milliseconds kRefreshIntervalIfErrored(200);
Milliseconds kMaxRefreshWaitTime(10 * 60 * 1000);

// Prevents the refresher thread from waiting longer than the given number of milliseconds, even on
// a successful refresh.
MONGO_FAIL_POINT_DEFINE(maxKeyRefreshWaitTimeOverrideMS);

/**
 * Returns the amount of time to wait until the monitoring thread should attempt to refresh again.
 */
Milliseconds howMuchSleepNeedFor(const LogicalTime& currentTime,
                                 const LogicalTime& latestExpiredAt,
                                 const Milliseconds& interval) {
    auto currentSecs = currentTime.asTimestamp().getSecs();
    auto expiredSecs = latestExpiredAt.asTimestamp().getSecs();

    if (currentSecs >= expiredSecs) {
        // This means that the last round didn't generate a usable key for the current time.
        // However, we don't want to poll too hard as well, so use a low interval.
        return kRefreshIntervalIfErrored;
    }

    auto millisBeforeExpire = 1000 * (expiredSecs - currentSecs);

    if (interval.count() <= millisBeforeExpire) {
        return interval;
    }

    return Milliseconds(millisBeforeExpire);
}

}  // unnamed namespace

KeysCollectionManager::KeysCollectionManager(std::string purpose,
                                             std::unique_ptr<KeysCollectionClient> client,
                                             Seconds keyValidForInterval)
    : _client(std::move(client)),
      _purpose(std::move(purpose)),
      _keyValidForInterval(keyValidForInterval),
      _keysCache(_purpose, _client.get()) {}


StatusWith<KeysCollectionDocument> KeysCollectionManager::getKeyForValidation(
    OperationContext* opCtx, long long keyId, const LogicalTime& forThisTime) {
    auto keyStatus = _getKeyWithKeyIdCheck(keyId, forThisTime);

    if (keyStatus != ErrorCodes::KeyNotFound) {
        return keyStatus;
    }

    _refresher.refreshNow(opCtx);

    return _getKeyWithKeyIdCheck(keyId, forThisTime);
}

StatusWith<KeysCollectionDocument> KeysCollectionManager::getKeyForSigning(
    OperationContext* opCtx, const LogicalTime& forThisTime) {
    return _getKey(forThisTime);
}

StatusWith<KeysCollectionDocument> KeysCollectionManager::_getKeyWithKeyIdCheck(
    long long keyId, const LogicalTime& forThisTime) {
    auto keyStatus = _keysCache.getKeyById(keyId, forThisTime);

    if (!keyStatus.isOK()) {
        return keyStatus;
    }

    return keyStatus.getValue();
}

StatusWith<KeysCollectionDocument> KeysCollectionManager::_getKey(const LogicalTime& forThisTime) {
    auto keyStatus = _keysCache.getKey(forThisTime);

    if (!keyStatus.isOK()) {
        return keyStatus;
    }

    const auto& key = keyStatus.getValue();

    if (key.getExpiresAt() < forThisTime) {
        return {ErrorCodes::KeyNotFound,
                str::stream() << "No keys found for " << _purpose << " that is valid for "
                              << forThisTime.toString()};
    }

    return key;
}

void KeysCollectionManager::refreshNow(OperationContext* opCtx) {
    _refresher.refreshNow(opCtx);
}

void KeysCollectionManager::startMonitoring(ServiceContext* service) {
    _keysCache.resetCache();
    _refresher.setFunc([this](OperationContext* opCtx) { return _keysCache.refresh(opCtx); });
    _refresher.start(
        service, str::stream() << "monitoring keys for " << _purpose, _keyValidForInterval);
}

void KeysCollectionManager::stopMonitoring() {
    _refresher.stop();
}

void KeysCollectionManager::enableKeyGenerator(OperationContext* opCtx, bool doEnable) {
    if (doEnable) {
        _refresher.switchFunc(opCtx, [this](OperationContext* opCtx) {
            KeyGenerator keyGenerator(_purpose, _client.get(), _keyValidForInterval);
            auto keyGenerationStatus = keyGenerator.generateNewKeysIfNeeded(opCtx);

            if (ErrorCodes::isShutdownError(keyGenerationStatus.code())) {
                return StatusWith<KeysCollectionDocument>(keyGenerationStatus);
            }

            // An error encountered by the keyGenerator should not prevent refreshing the cache
            auto cacheRefreshStatus = _keysCache.refresh(opCtx);

            if (!keyGenerationStatus.isOK()) {
                return StatusWith<KeysCollectionDocument>(keyGenerationStatus);
            }

            return cacheRefreshStatus;
        });
    } else {
        _refresher.switchFunc(
            opCtx, [this](OperationContext* opCtx) { return _keysCache.refresh(opCtx); });
    }
}

bool KeysCollectionManager::hasSeenKeys() {
    return _refresher.hasSeenKeys();
}

void KeysCollectionManager::clearCache() {
    _keysCache.resetCache();
}

void KeysCollectionManager::PeriodicRunner::refreshNow(OperationContext* opCtx) {
    auto refreshRequest = [this]() {
        stdx::lock_guard<stdx::mutex> lk(_mutex);

        if (_inShutdown) {
            uasserted(ErrorCodes::ShutdownInProgress,
                      "aborting keys cache refresh because node is shutting down");
        }

        if (_refreshRequest) {
            return _refreshRequest;
        }

        _refreshNeededCV.notify_all();
        _refreshRequest = std::make_shared<Notification<void>>();
        return _refreshRequest;
    }();

    // note: waitFor waits min(maxTimeMS, kDefaultRefreshWaitTime).
    // waitFor also throws if timeout, so also throw when notification was not satisfied after
    // waiting.
    if (!refreshRequest->waitFor(opCtx, kDefaultRefreshWaitTime)) {
        uasserted(ErrorCodes::ExceededTimeLimit, "timed out waiting for refresh");
    }
}

void KeysCollectionManager::PeriodicRunner::_doPeriodicRefresh(ServiceContext* service,
                                                               std::string threadName,
                                                               Milliseconds refreshInterval) {
    Client::initThreadIfNotAlready(threadName);

    while (true) {
        bool hasRefreshRequestInitially = false;
        unsigned errorCount = 0;
        std::shared_ptr<RefreshFunc> doRefresh;
        {
            stdx::lock_guard<stdx::mutex> lock(_mutex);

            if (_inShutdown) {
                break;
            }

            invariant(_doRefresh.get() != nullptr);
            doRefresh = _doRefresh;
            hasRefreshRequestInitially = _refreshRequest.get() != nullptr;
        }

        Milliseconds nextWakeup = kRefreshIntervalIfErrored;

        {
            auto opCtx = cc().makeOperationContext();

            auto latestKeyStatusWith = (*doRefresh)(opCtx.get());
            if (latestKeyStatusWith.getStatus().isOK()) {
                errorCount = 0;
                const auto& latestKey = latestKeyStatusWith.getValue();
                auto currentTime = LogicalClock::get(service)->getClusterTime();

                {
                    stdx::unique_lock<stdx::mutex> lock(_mutex);
                    _hasSeenKeys = true;
                }

                nextWakeup =
                    howMuchSleepNeedFor(currentTime, latestKey.getExpiresAt(), refreshInterval);
            } else {
                errorCount += 1;
                nextWakeup = Milliseconds(kRefreshIntervalIfErrored.count() * errorCount);
                if (nextWakeup > kMaxRefreshWaitTime) {
                    nextWakeup = kMaxRefreshWaitTime;
                }
            }
        }

        MONGO_FAIL_POINT_BLOCK(maxKeyRefreshWaitTimeOverrideMS, data) {
            const BSONObj& dataObj = data.getData();
            auto overrideMS = Milliseconds(dataObj["overrideMS"].numberInt());
            if (nextWakeup > overrideMS) {
                nextWakeup = overrideMS;
            }
        }

        stdx::unique_lock<stdx::mutex> lock(_mutex);

        if (_refreshRequest) {
            if (!hasRefreshRequestInitially) {
                // A fresh request came in, fulfill the request before going to sleep.
                continue;
            }

            _refreshRequest->set();
            _refreshRequest.reset();
        }

        if (_inShutdown) {
            break;
        }

        // Use a new opCtx so we won't be holding any RecoveryUnit while this thread goes to sleep.
        auto opCtx = cc().makeOperationContext();

        MONGO_IDLE_THREAD_BLOCK;
        auto sleepStatus = opCtx->waitForConditionOrInterruptNoAssertUntil(
            _refreshNeededCV, lock, Date_t::now() + nextWakeup);

        if (ErrorCodes::isShutdownError(sleepStatus.getStatus().code())) {
            break;
        }
    }

    stdx::unique_lock<stdx::mutex> lock(_mutex);
    if (_refreshRequest) {
        _refreshRequest->set();
        _refreshRequest.reset();
    }
}

void KeysCollectionManager::PeriodicRunner::setFunc(RefreshFunc newRefreshStrategy) {
    stdx::lock_guard<stdx::mutex> lock(_mutex);
    _doRefresh = std::make_shared<RefreshFunc>(std::move(newRefreshStrategy));
    _refreshNeededCV.notify_all();
}

void KeysCollectionManager::PeriodicRunner::switchFunc(OperationContext* opCtx,
                                                       RefreshFunc newRefreshStrategy) {
    setFunc(newRefreshStrategy);
}

void KeysCollectionManager::PeriodicRunner::start(ServiceContext* service,
                                                  const std::string& threadName,
                                                  Milliseconds refreshInterval) {
    stdx::lock_guard<stdx::mutex> lock(_mutex);
    invariant(!_backgroundThread.joinable());
    invariant(!_inShutdown);

    _backgroundThread = stdx::thread([this, service, threadName, refreshInterval] {
        _doPeriodicRefresh(service, threadName, refreshInterval);
    });
}

void KeysCollectionManager::PeriodicRunner::stop() {
    {
        stdx::lock_guard<stdx::mutex> lock(_mutex);
        if (!_backgroundThread.joinable()) {
            return;
        }

        _inShutdown = true;
        _hasSeenKeys = false;
        _refreshNeededCV.notify_all();
    }

    _backgroundThread.join();
}

bool KeysCollectionManager::PeriodicRunner::hasSeenKeys() {
    stdx::lock_guard<stdx::mutex> lock(_mutex);
    return _hasSeenKeys;
}

}  // namespace mongo