summaryrefslogtreecommitdiffstats
path: root/security/nss/lib/ssl/sslnonce.c
blob: 228834e3dbefff3743c21da14e8fbdc8be6bfe53 (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
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
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file implements the CLIENT Session ID cache.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "cert.h"
#include "pk11pub.h"
#include "secitem.h"
#include "ssl.h"
#include "nss.h"

#include "sslimpl.h"
#include "sslproto.h"
#include "nssilock.h"
#if defined(XP_UNIX) || defined(XP_WIN) || defined(_WINDOWS) || defined(XP_BEOS)
#include <time.h>
#endif

PRUint32 ssl3_sid_timeout = 86400L; /* 24 hours */

static sslSessionID *cache = NULL;
static PZLock *cacheLock = NULL;

/* sids can be in one of 4 states:
 *
 * never_cached,        created, but not yet put into cache.
 * in_client_cache,     in the client cache's linked list.
 * in_server_cache,     entry came from the server's cache file.
 * invalid_cache        has been removed from the cache.
 */

#define LOCK_CACHE lock_cache()
#define UNLOCK_CACHE PZ_Unlock(cacheLock)

static SECStatus
ssl_InitClientSessionCacheLock(void)
{
    cacheLock = PZ_NewLock(nssILockCache);
    return cacheLock ? SECSuccess : SECFailure;
}

static SECStatus
ssl_FreeClientSessionCacheLock(void)
{
    if (cacheLock) {
        PZ_DestroyLock(cacheLock);
        cacheLock = NULL;
        return SECSuccess;
    }
    PORT_SetError(SEC_ERROR_NOT_INITIALIZED);
    return SECFailure;
}

static PRBool LocksInitializedEarly = PR_FALSE;

static SECStatus
FreeSessionCacheLocks()
{
    SECStatus rv1, rv2;
    rv1 = ssl_FreeSymWrapKeysLock();
    rv2 = ssl_FreeClientSessionCacheLock();
    if ((SECSuccess == rv1) && (SECSuccess == rv2)) {
        return SECSuccess;
    }
    return SECFailure;
}

static SECStatus
InitSessionCacheLocks(void)
{
    SECStatus rv1, rv2;
    PRErrorCode rc;
    rv1 = ssl_InitSymWrapKeysLock();
    rv2 = ssl_InitClientSessionCacheLock();
    if ((SECSuccess == rv1) && (SECSuccess == rv2)) {
        return SECSuccess;
    }
    rc = PORT_GetError();
    FreeSessionCacheLocks();
    PORT_SetError(rc);
    return SECFailure;
}

/* free the session cache locks if they were initialized early */
SECStatus
ssl_FreeSessionCacheLocks()
{
    PORT_Assert(PR_TRUE == LocksInitializedEarly);
    if (!LocksInitializedEarly) {
        PORT_SetError(SEC_ERROR_NOT_INITIALIZED);
        return SECFailure;
    }
    FreeSessionCacheLocks();
    LocksInitializedEarly = PR_FALSE;
    return SECSuccess;
}

static PRCallOnceType lockOnce;

/* free the session cache locks if they were initialized lazily */
static SECStatus
ssl_ShutdownLocks(void *appData, void *nssData)
{
    PORT_Assert(PR_FALSE == LocksInitializedEarly);
    if (LocksInitializedEarly) {
        PORT_SetError(SEC_ERROR_LIBRARY_FAILURE);
        return SECFailure;
    }
    FreeSessionCacheLocks();
    memset(&lockOnce, 0, sizeof(lockOnce));
    return SECSuccess;
}

static PRStatus
initSessionCacheLocksLazily(void)
{
    SECStatus rv = InitSessionCacheLocks();
    if (SECSuccess != rv) {
        return PR_FAILURE;
    }
    rv = NSS_RegisterShutdown(ssl_ShutdownLocks, NULL);
    PORT_Assert(SECSuccess == rv);
    if (SECSuccess != rv) {
        return PR_FAILURE;
    }
    return PR_SUCCESS;
}

/* lazyInit means that the call is not happening during a 1-time
 * initialization function, but rather during dynamic, lazy initialization
 */
SECStatus
ssl_InitSessionCacheLocks(PRBool lazyInit)
{
    if (LocksInitializedEarly) {
        return SECSuccess;
    }

    if (lazyInit) {
        return (PR_SUCCESS ==
                PR_CallOnce(&lockOnce, initSessionCacheLocksLazily))
                   ? SECSuccess
                   : SECFailure;
    }

    if (SECSuccess == InitSessionCacheLocks()) {
        LocksInitializedEarly = PR_TRUE;
        return SECSuccess;
    }

    return SECFailure;
}

static void
lock_cache(void)
{
    ssl_InitSessionCacheLocks(PR_TRUE);
    PZ_Lock(cacheLock);
}

/* BEWARE: This function gets called for both client and server SIDs !!
 * If the unreferenced sid is not in the cache, Free sid and its contents.
 */
static void
ssl_DestroySID(sslSessionID *sid)
{
    SSL_TRC(8, ("SSL: destroy sid: sid=0x%x cached=%d", sid, sid->cached));
    PORT_Assert(sid->references == 0);
    PORT_Assert(sid->cached != in_client_cache);

    if (sid->u.ssl3.locked.sessionTicket.ticket.data) {
        SECITEM_FreeItem(&sid->u.ssl3.locked.sessionTicket.ticket,
                         PR_FALSE);
    }
    if (sid->u.ssl3.srvName.data) {
        SECITEM_FreeItem(&sid->u.ssl3.srvName, PR_FALSE);
    }
    if (sid->u.ssl3.signedCertTimestamps.data) {
        SECITEM_FreeItem(&sid->u.ssl3.signedCertTimestamps, PR_FALSE);
    }

    if (sid->u.ssl3.lock) {
        PR_DestroyRWLock(sid->u.ssl3.lock);
    }

    if (sid->peerID != NULL)
        PORT_Free((void *)sid->peerID); /* CONST */

    if (sid->urlSvrName != NULL)
        PORT_Free((void *)sid->urlSvrName); /* CONST */

    if (sid->peerCert) {
        CERT_DestroyCertificate(sid->peerCert);
    }
    if (sid->peerCertStatus.items) {
        SECITEM_FreeArray(&sid->peerCertStatus, PR_FALSE);
    }

    if (sid->localCert) {
        CERT_DestroyCertificate(sid->localCert);
    }

    SECITEM_FreeItem(&sid->u.ssl3.alpnSelection, PR_FALSE);

    PORT_ZFree(sid, sizeof(sslSessionID));
}

/* BEWARE: This function gets called for both client and server SIDs !!
 * Decrement reference count, and
 *    free sid if ref count is zero, and sid is not in the cache.
 * Does NOT remove from the cache first.
 * If the sid is still in the cache, it is left there until next time
 * the cache list is traversed.
 */
static void
ssl_FreeLockedSID(sslSessionID *sid)
{
    PORT_Assert(sid->references >= 1);
    if (--sid->references == 0) {
        ssl_DestroySID(sid);
    }
}

/* BEWARE: This function gets called for both client and server SIDs !!
 * Decrement reference count, and
 *    free sid if ref count is zero, and sid is not in the cache.
 * Does NOT remove from the cache first.
 * These locks are necessary because the sid _might_ be in the cache list.
 */
void
ssl_FreeSID(sslSessionID *sid)
{
    LOCK_CACHE;
    ssl_FreeLockedSID(sid);
    UNLOCK_CACHE;
}

/************************************************************************/

/*
**  Lookup sid entry in cache by Address, port, and peerID string.
**  If found, Increment reference count, and return pointer to caller.
**  If it has timed out or ref count is zero, remove from list and free it.
*/

sslSessionID *
ssl_LookupSID(const PRIPv6Addr *addr, PRUint16 port, const char *peerID,
              const char *urlSvrName)
{
    sslSessionID **sidp;
    sslSessionID *sid;
    PRUint32 now;

    if (!urlSvrName)
        return NULL;
    now = ssl_TimeSec();
    LOCK_CACHE;
    sidp = &cache;
    while ((sid = *sidp) != 0) {
        PORT_Assert(sid->cached == in_client_cache);
        PORT_Assert(sid->references >= 1);

        SSL_TRC(8, ("SSL: Lookup1: sid=0x%x", sid));

        if (sid->expirationTime < now) {
            /*
            ** This session-id timed out.
            ** Don't even care who it belongs to, blow it out of our cache.
            */
            SSL_TRC(7, ("SSL: lookup1, throwing sid out, age=%d refs=%d",
                        now - sid->creationTime, sid->references));

            *sidp = sid->next;                                      /* delink it from the list. */
            sid->cached = invalid_cache;                            /* mark not on list. */
            ssl_FreeLockedSID(sid);                                 /* drop ref count, free. */
        } else if (!memcmp(&sid->addr, addr, sizeof(PRIPv6Addr)) && /* server IP addr matches */
                   (sid->port == port) &&                           /* server port matches */
                   /* proxy (peerID) matches */
                   (((peerID == NULL) && (sid->peerID == NULL)) ||
                    ((peerID != NULL) && (sid->peerID != NULL) &&
                     PORT_Strcmp(sid->peerID, peerID) == 0)) &&
                   /* is cacheable */
                   (sid->u.ssl3.keys.resumable) &&
                   /* server hostname matches. */
                   (sid->urlSvrName != NULL) &&
                   (0 == PORT_Strcmp(urlSvrName, sid->urlSvrName))) {
            /* Hit */
            sid->lastAccessTime = now;
            sid->references++;
            break;
        } else {
            sidp = &sid->next;
        }
    }
    UNLOCK_CACHE;
    return sid;
}

/*
** Add an sid to the cache or return a previously cached entry to the cache.
** Although this is static, it is called via ss->sec.cache().
*/
static void
CacheSID(sslSessionID *sid)
{
    PORT_Assert(sid->cached == never_cached);

    SSL_TRC(8, ("SSL: Cache: sid=0x%x cached=%d addr=0x%08x%08x%08x%08x port=0x%04x "
                "time=%x cached=%d",
                sid, sid->cached, sid->addr.pr_s6_addr32[0],
                sid->addr.pr_s6_addr32[1], sid->addr.pr_s6_addr32[2],
                sid->addr.pr_s6_addr32[3], sid->port, sid->creationTime,
                sid->cached));

    if (!sid->urlSvrName) {
        /* don't cache this SID because it can never be matched */
        return;
    }

    if (sid->u.ssl3.sessionIDLength == 0 &&
        sid->u.ssl3.locked.sessionTicket.ticket.data == NULL)
        return;

    /* Client generates the SessionID if this was a stateless resume. */
    if (sid->u.ssl3.sessionIDLength == 0) {
        SECStatus rv;
        rv = PK11_GenerateRandom(sid->u.ssl3.sessionID,
                                 SSL3_SESSIONID_BYTES);
        if (rv != SECSuccess)
            return;
        sid->u.ssl3.sessionIDLength = SSL3_SESSIONID_BYTES;
    }
    PRINT_BUF(8, (0, "sessionID:",
                  sid->u.ssl3.sessionID, sid->u.ssl3.sessionIDLength));

    sid->u.ssl3.lock = PR_NewRWLock(PR_RWLOCK_RANK_NONE, NULL);
    if (!sid->u.ssl3.lock) {
        return;
    }
    PORT_Assert(sid->creationTime != 0 && sid->expirationTime != 0);
    if (!sid->creationTime)
        sid->lastAccessTime = sid->creationTime = ssl_TimeUsec();
    if (!sid->expirationTime)
        sid->expirationTime = sid->creationTime + ssl3_sid_timeout * PR_USEC_PER_SEC;

    /*
     * Put sid into the cache.  Bump reference count to indicate that
     * cache is holding a reference. Uncache will reduce the cache
     * reference.
     */
    LOCK_CACHE;
    sid->references++;
    sid->cached = in_client_cache;
    sid->next = cache;
    cache = sid;
    UNLOCK_CACHE;
}

/*
 * If sid "zap" is in the cache,
 *    removes sid from cache, and decrements reference count.
 * Caller must hold cache lock.
 */
static void
UncacheSID(sslSessionID *zap)
{
    sslSessionID **sidp = &cache;
    sslSessionID *sid;

    if (zap->cached != in_client_cache) {
        return;
    }

    SSL_TRC(8, ("SSL: Uncache: zap=0x%x cached=%d addr=0x%08x%08x%08x%08x port=0x%04x "
                "time=%x cipherSuite=%d",
                zap, zap->cached, zap->addr.pr_s6_addr32[0],
                zap->addr.pr_s6_addr32[1], zap->addr.pr_s6_addr32[2],
                zap->addr.pr_s6_addr32[3], zap->port, zap->creationTime,
                zap->u.ssl3.cipherSuite));

    /* See if it's in the cache, if so nuke it */
    while ((sid = *sidp) != 0) {
        if (sid == zap) {
            /*
            ** Bingo. Reduce reference count by one so that when
            ** everyone is done with the sid we can free it up.
            */
            *sidp = zap->next;
            zap->cached = invalid_cache;
            ssl_FreeLockedSID(zap);
            return;
        }
        sidp = &sid->next;
    }
}

/* If sid "zap" is in the cache,
 *    removes sid from cache, and decrements reference count.
 * Although this function is static, it is called externally via
 *    ss->sec.uncache().
 */
static void
LockAndUncacheSID(sslSessionID *zap)
{
    LOCK_CACHE;
    UncacheSID(zap);
    UNLOCK_CACHE;
}

/* choose client or server cache functions for this sslsocket. */
void
ssl_ChooseSessionIDProcs(sslSecurityInfo *sec)
{
    if (sec->isServer) {
        sec->cache = ssl_sid_cache;
        sec->uncache = ssl_sid_uncache;
    } else {
        sec->cache = CacheSID;
        sec->uncache = LockAndUncacheSID;
    }
}

/* wipe out the entire client session cache. */
void
SSL_ClearSessionCache(void)
{
    LOCK_CACHE;
    while (cache != NULL)
        UncacheSID(cache);
    UNLOCK_CACHE;
}

/* returns an unsigned int containing the number of seconds in PR_Now() */
PRUint32
ssl_TimeSec(void)
{
#ifdef UNSAFE_FUZZER_MODE
    return 1234;
#endif

    PRUint32 myTime;
#if defined(XP_UNIX) || defined(XP_WIN) || defined(_WINDOWS) || defined(XP_BEOS)
    myTime = time(NULL); /* accurate until the year 2038. */
#else
    /* portable, but possibly slower */
    PRTime now;
    PRInt64 ll;

    now = PR_Now();
    LL_I2L(ll, 1000000L);
    LL_DIV(now, now, ll);
    LL_L2UI(myTime, now);
#endif
    return myTime;
}

PRBool
ssl_TicketTimeValid(const NewSessionTicket *ticket)
{
    PRTime endTime;

    if (ticket->ticket_lifetime_hint == 0) {
        return PR_TRUE;
    }

    endTime = ticket->received_timestamp +
              (PRTime)(ticket->ticket_lifetime_hint * PR_USEC_PER_SEC);
    return endTime > ssl_TimeUsec();
}

void
ssl3_SetSIDSessionTicket(sslSessionID *sid,
                         /*in/out*/ NewSessionTicket *newSessionTicket)
{
    PORT_Assert(sid);
    PORT_Assert(newSessionTicket);
    PORT_Assert(newSessionTicket->ticket.data);
    PORT_Assert(newSessionTicket->ticket.len != 0);

    /* if sid->u.ssl3.lock, we are updating an existing entry that is already
     * cached or was once cached, so we need to acquire and release the write
     * lock. Otherwise, this is a new session that isn't shared with anything
     * yet, so no locking is needed.
     */
    if (sid->u.ssl3.lock) {
        PR_RWLock_Wlock(sid->u.ssl3.lock);
        if (sid->u.ssl3.locked.sessionTicket.ticket.data) {
            SECITEM_FreeItem(&sid->u.ssl3.locked.sessionTicket.ticket,
                             PR_FALSE);
        }
    }

    PORT_Assert(!sid->u.ssl3.locked.sessionTicket.ticket.data);

    /* Do a shallow copy, moving the ticket data. */
    sid->u.ssl3.locked.sessionTicket = *newSessionTicket;
    newSessionTicket->ticket.data = NULL;
    newSessionTicket->ticket.len = 0;

    if (sid->u.ssl3.lock) {
        PR_RWLock_Unlock(sid->u.ssl3.lock);
    }
}