net/third_party/nss/ssl/sslnonce.c

   1 /*
   2  * This file implements the CLIENT Session ID cache.
   3  *
   4  * This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   7
   8 #include "cert.h"
   9 #include "pk11pub.h"
  10 #include "secitem.h"
  11 #include "ssl.h"
  12 #include "nss.h"
  13
  14 #include "sslimpl.h"
  15 #include "sslproto.h"
  16 #include "nssilock.h"
  17 #if defined(XP_UNIX) || defined(XP_WIN) || defined(_WINDOWS) || defined(XP_BEOS)
  18 #include <time.h>
  19 #endif
  20
  21 PRUint32 ssl_sid_timeout = 100;
  22 PRUint32 ssl3_sid_timeout = 86400L; /* 24 hours */
  23
  24 static sslSessionID *cache = NULL;
  25 static PZLock *      cacheLock = NULL;
  26
  27 /* sids can be in one of 4 states:
  28  *
  29  * never_cached,        created, but not yet put into cache.
  30  * in_client_cache,     in the client cache's linked list.
  31  * in_server_cache,     entry came from the server's cache file.
  32  * invalid_cache        has been removed from the cache.
  33  */
  34
  35 #define LOCK_CACHE      lock_cache()
  36 #define UNLOCK_CACHE    PZ_Unlock(cacheLock)
  37
  38 static PRCallOnceType lockOnce;
  39
  40 /* FreeSessionCacheLocks is a callback from NSS_RegisterShutdown which destroys
  41  * the session cache locks on shutdown and resets them to their initial
  42  * state. */
  43 static SECStatus
  44 FreeSessionCacheLocks(void* appData, void* nssData)
  45 {
  46     static const PRCallOnceType pristineCallOnce;
  47     SECStatus rv;
  48
  49     if (!cacheLock) {
  50         PORT_SetError(SEC_ERROR_NOT_INITIALIZED);
  51         return SECFailure;
  52     }
  53
  54     PZ_DestroyLock(cacheLock);
  55     cacheLock = NULL;
  56
  57     rv = ssl_FreeSymWrapKeysLock();
  58     if (rv != SECSuccess) {
  59         return rv;
  60     }
  61
  62     lockOnce = pristineCallOnce;
  63     return SECSuccess;
  64 }
  65
  66 /* InitSessionCacheLocks is called, protected by lockOnce, to create the
  67  * session cache locks. */
  68 static PRStatus
  69 InitSessionCacheLocks(void)
  70 {
  71     SECStatus rv;
  72
  73     cacheLock = PZ_NewLock(nssILockCache);
  74     if (cacheLock == NULL) {
  75         return PR_FAILURE;
  76     }
  77     rv = ssl_InitSymWrapKeysLock();
  78     if (rv != SECSuccess) {
  79         PRErrorCode error = PORT_GetError();
  80         PZ_DestroyLock(cacheLock);
  81         cacheLock = NULL;
  82         PORT_SetError(error);
  83         return PR_FAILURE;
  84     }
  85
  86     rv = NSS_RegisterShutdown(FreeSessionCacheLocks, NULL);
  87     PORT_Assert(SECSuccess == rv);
  88     if (SECSuccess != rv) {
  89         return PR_FAILURE;
  90     }
  91     return PR_SUCCESS;
  92 }
  93
  94 SECStatus
  95 ssl_InitSessionCacheLocks(void)
  96 {
  97     return (PR_SUCCESS ==
  98             PR_CallOnce(&lockOnce, InitSessionCacheLocks)) ?
  99            SECSuccess : SECFailure;
 100 }
 101
 102 static void
 103 lock_cache(void)
 104 {
 105     ssl_InitSessionCacheLocks();
 106     PZ_Lock(cacheLock);
 107 }
 108
 109 /* BEWARE: This function gets called for both client and server SIDs !!
 110  * If the unreferenced sid is not in the cache, Free sid and its contents.
 111  */
 112 static void
 113 ssl_DestroySID(sslSessionID *sid)
 114 {
 115     int i;
 116     SSL_TRC(8, ("SSL: destroy sid: sid=0x%x cached=%d", sid, sid->cached));
 117     PORT_Assert(sid->references == 0);
 118     PORT_Assert(sid->cached != in_client_cache);
 119
 120     if (sid->version < SSL_LIBRARY_VERSION_3_0) {
 121         SECITEM_ZfreeItem(&sid->u.ssl2.masterKey, PR_FALSE);
 122         SECITEM_ZfreeItem(&sid->u.ssl2.cipherArg, PR_FALSE);
 123     } else {
 124         if (sid->u.ssl3.locked.sessionTicket.ticket.data) {
 125             SECITEM_FreeItem(&sid->u.ssl3.locked.sessionTicket.ticket,
 126                              PR_FALSE);
 127         }
 128         if (sid->u.ssl3.srvName.data) {
 129             SECITEM_FreeItem(&sid->u.ssl3.srvName, PR_FALSE);
 130         }
 131         if (sid->u.ssl3.originalHandshakeHash.data) {
 132             SECITEM_FreeItem(&sid->u.ssl3.originalHandshakeHash, PR_FALSE);
 133         }
 134         if (sid->u.ssl3.signedCertTimestamps.data) {
 135             SECITEM_FreeItem(&sid->u.ssl3.signedCertTimestamps, PR_FALSE);
 136         }
 137
 138         if (sid->u.ssl3.lock) {
 139             NSSRWLock_Destroy(sid->u.ssl3.lock);
 140         }
 141     }
 142
 143     if (sid->peerID != NULL)
 144         PORT_Free((void *)sid->peerID);         /* CONST */
 145
 146     if (sid->urlSvrName != NULL)
 147         PORT_Free((void *)sid->urlSvrName);     /* CONST */
 148
 149     if ( sid->peerCert ) {
 150         CERT_DestroyCertificate(sid->peerCert);
 151     }
 152     for (i = 0; i < MAX_PEER_CERT_CHAIN_SIZE && sid->peerCertChain[i]; i++) {
 153         CERT_DestroyCertificate(sid->peerCertChain[i]);
 154     }
 155     if (sid->peerCertStatus.items) {
 156         SECITEM_FreeArray(&sid->peerCertStatus, PR_FALSE);
 157     }
 158
 159     if ( sid->localCert ) {
 160         CERT_DestroyCertificate(sid->localCert);
 161     }
 162
 163     PORT_ZFree(sid, sizeof(sslSessionID));
 164 }
 165
 166 /* BEWARE: This function gets called for both client and server SIDs !!
 167  * Decrement reference count, and
 168  *    free sid if ref count is zero, and sid is not in the cache.
 169  * Does NOT remove from the cache first.
 170  * If the sid is still in the cache, it is left there until next time
 171  * the cache list is traversed.
 172  */
 173 static void
 174 ssl_FreeLockedSID(sslSessionID *sid)
 175 {
 176     PORT_Assert(sid->references >= 1);
 177     if (--sid->references == 0) {
 178         ssl_DestroySID(sid);
 179     }
 180 }
 181
 182 /* BEWARE: This function gets called for both client and server SIDs !!
 183  * Decrement reference count, and
 184  *    free sid if ref count is zero, and sid is not in the cache.
 185  * Does NOT remove from the cache first.
 186  * These locks are necessary because the sid _might_ be in the cache list.
 187  */
 188 void
 189 ssl_FreeSID(sslSessionID *sid)
 190 {
 191     LOCK_CACHE;
 192     ssl_FreeLockedSID(sid);
 193     UNLOCK_CACHE;
 194 }
 195
 196 /************************************************************************/
 197
 198 /*
 199 **  Lookup sid entry in cache by Address, port, and peerID string.
 200 **  If found, Increment reference count, and return pointer to caller.
 201 **  If it has timed out or ref count is zero, remove from list and free it.
 202 */
 203
 204 sslSessionID *
 205 ssl_LookupSID(const PRIPv6Addr *addr, PRUint16 port, const char *peerID,
 206               const char * urlSvrName)
 207 {
 208     sslSessionID **sidp;
 209     sslSessionID * sid;
 210     PRUint32       now;
 211
 212     if (!urlSvrName)
 213         return NULL;
 214     now = ssl_Time();
 215     LOCK_CACHE;
 216     sidp = &cache;
 217     while ((sid = *sidp) != 0) {
 218         PORT_Assert(sid->cached == in_client_cache);
 219         PORT_Assert(sid->references >= 1);
 220
 221         SSL_TRC(8, ("SSL: Lookup1: sid=0x%x", sid));
 222
 223         if (sid->expirationTime < now) {
 224             /*
 225             ** This session-id timed out.
 226             ** Don't even care who it belongs to, blow it out of our cache.
 227             */
 228             SSL_TRC(7, ("SSL: lookup1, throwing sid out, age=%d refs=%d",
 229                         now - sid->creationTime, sid->references));
 230
 231             *sidp = sid->next;                  /* delink it from the list. */
 232             sid->cached = invalid_cache;        /* mark not on list. */
 233             ssl_FreeLockedSID(sid);             /* drop ref count, free. */
 234         } else if (!memcmp(&sid->addr, addr, sizeof(PRIPv6Addr)) && /* server IP addr matches */
 235                    (sid->port == port) && /* server port matches */
 236                    /* proxy (peerID) matches */
 237                    (((peerID == NULL) && (sid->peerID == NULL)) ||
 238                     ((peerID != NULL) && (sid->peerID != NULL) &&
 239                      PORT_Strcmp(sid->peerID, peerID) == 0)) &&
 240                    /* is cacheable */
 241                    (sid->version < SSL_LIBRARY_VERSION_3_0 ||
 242                     sid->u.ssl3.keys.resumable) &&
 243                    /* server hostname matches. */
 244                    (sid->urlSvrName != NULL) &&
 245                    ((0 == PORT_Strcmp(urlSvrName, sid->urlSvrName)) ||
 246                     ((sid->peerCert != NULL) && (SECSuccess ==
 247                       CERT_VerifyCertName(sid->peerCert, urlSvrName))) )
 248                   ) {
 249             /* Hit */
 250             sid->lastAccessTime = now;
 251             sid->references++;
 252             break;
 253         } else {
 254             sidp = &sid->next;
 255         }
 256     }
 257     UNLOCK_CACHE;
 258     return sid;
 259 }
 260
 261 /*
 262 ** Add an sid to the cache or return a previously cached entry to the cache.
 263 ** Although this is static, it is called via ss->sec.cache().
 264 */
 265 static void
 266 CacheSID(sslSessionID *sid)
 267 {
 268     PRUint32  expirationPeriod;
 269
 270     PORT_Assert(sid->cached == never_cached);
 271
 272     SSL_TRC(8, ("SSL: Cache: sid=0x%x cached=%d addr=0x%08x%08x%08x%08x port=0x%04x "
 273                 "time=%x cached=%d",
 274                 sid, sid->cached, sid->addr.pr_s6_addr32[0],
 275                 sid->addr.pr_s6_addr32[1], sid->addr.pr_s6_addr32[2],
 276                 sid->addr.pr_s6_addr32[3],  sid->port, sid->creationTime,
 277                 sid->cached));
 278
 279     if (!sid->urlSvrName) {
 280         /* don't cache this SID because it can never be matched */
 281         return;
 282     }
 283
 284     /* XXX should be different trace for version 2 vs. version 3 */
 285     if (sid->version < SSL_LIBRARY_VERSION_3_0) {
 286         expirationPeriod = ssl_sid_timeout;
 287         PRINT_BUF(8, (0, "sessionID:",
 288                   sid->u.ssl2.sessionID, sizeof(sid->u.ssl2.sessionID)));
 289         PRINT_BUF(8, (0, "masterKey:",
 290                   sid->u.ssl2.masterKey.data, sid->u.ssl2.masterKey.len));
 291         PRINT_BUF(8, (0, "cipherArg:",
 292                   sid->u.ssl2.cipherArg.data, sid->u.ssl2.cipherArg.len));
 293     } else {
 294         if (sid->u.ssl3.sessionIDLength == 0 &&
 295             sid->u.ssl3.locked.sessionTicket.ticket.data == NULL)
 296             return;
 297
 298         /* Client generates the SessionID if this was a stateless resume. */
 299         if (sid->u.ssl3.sessionIDLength == 0) {
 300             SECStatus rv;
 301             rv = PK11_GenerateRandom(sid->u.ssl3.sessionID,
 302                 SSL3_SESSIONID_BYTES);
 303             if (rv != SECSuccess)
 304                 return;
 305             sid->u.ssl3.sessionIDLength = SSL3_SESSIONID_BYTES;
 306         }
 307         expirationPeriod = ssl3_sid_timeout;
 308         PRINT_BUF(8, (0, "sessionID:",
 309                       sid->u.ssl3.sessionID, sid->u.ssl3.sessionIDLength));
 310
 311         sid->u.ssl3.lock = NSSRWLock_New(NSS_RWLOCK_RANK_NONE, NULL);
 312         if (!sid->u.ssl3.lock) {
 313             return;
 314         }
 315     }
 316     PORT_Assert(sid->creationTime != 0 && sid->expirationTime != 0);
 317     if (!sid->creationTime)
 318         sid->lastAccessTime = sid->creationTime = ssl_Time();
 319     if (!sid->expirationTime)
 320         sid->expirationTime = sid->creationTime + expirationPeriod;
 321
 322     /*
 323      * Put sid into the cache.  Bump reference count to indicate that
 324      * cache is holding a reference. Uncache will reduce the cache
 325      * reference.
 326      */
 327     LOCK_CACHE;
 328     sid->references++;
 329     sid->cached = in_client_cache;
 330     sid->next   = cache;
 331     cache       = sid;
 332     UNLOCK_CACHE;
 333 }
 334
 335 /*
 336  * If sid "zap" is in the cache,
 337  *    removes sid from cache, and decrements reference count.
 338  * Caller must hold cache lock.
 339  */
 340 static void
 341 UncacheSID(sslSessionID *zap)
 342 {
 343     sslSessionID **sidp = &cache;
 344     sslSessionID *sid;
 345
 346     if (zap->cached != in_client_cache) {
 347         return;
 348     }
 349
 350     SSL_TRC(8,("SSL: Uncache: zap=0x%x cached=%d addr=0x%08x%08x%08x%08x port=0x%04x "
 351                "time=%x cipher=%d",
 352                zap, zap->cached, zap->addr.pr_s6_addr32[0],
 353                zap->addr.pr_s6_addr32[1], zap->addr.pr_s6_addr32[2],
 354                zap->addr.pr_s6_addr32[3], zap->port, zap->creationTime,
 355                zap->u.ssl2.cipherType));
 356     if (zap->version < SSL_LIBRARY_VERSION_3_0) {
 357         PRINT_BUF(8, (0, "sessionID:",
 358                       zap->u.ssl2.sessionID, sizeof(zap->u.ssl2.sessionID)));
 359         PRINT_BUF(8, (0, "masterKey:",
 360                       zap->u.ssl2.masterKey.data, zap->u.ssl2.masterKey.len));
 361         PRINT_BUF(8, (0, "cipherArg:",
 362                       zap->u.ssl2.cipherArg.data, zap->u.ssl2.cipherArg.len));
 363     }
 364
 365     /* See if it's in the cache, if so nuke it */
 366     while ((sid = *sidp) != 0) {
 367         if (sid == zap) {
 368             /*
 369             ** Bingo. Reduce reference count by one so that when
 370             ** everyone is done with the sid we can free it up.
 371             */
 372             *sidp = zap->next;
 373             zap->cached = invalid_cache;
 374             ssl_FreeLockedSID(zap);
 375             return;
 376         }
 377         sidp = &sid->next;
 378     }
 379 }
 380
 381 /* If sid "zap" is in the cache,
 382  *    removes sid from cache, and decrements reference count.
 383  * Although this function is static, it is called externally via
 384  *    ss->sec.uncache().
 385  */
 386 static void
 387 LockAndUncacheSID(sslSessionID *zap)
 388 {
 389     LOCK_CACHE;
 390     UncacheSID(zap);
 391     UNLOCK_CACHE;
 392
 393 }
 394
 395 /* choose client or server cache functions for this sslsocket. */
 396 void
 397 ssl_ChooseSessionIDProcs(sslSecurityInfo *sec)
 398 {
 399     if (sec->isServer) {
 400         sec->cache   = ssl_sid_cache;
 401         sec->uncache = ssl_sid_uncache;
 402     } else {
 403         sec->cache   = CacheSID;
 404         sec->uncache = LockAndUncacheSID;
 405     }
 406 }
 407
 408 /* wipe out the entire client session cache. */
 409 void
 410 SSL_ClearSessionCache(void)
 411 {
 412     LOCK_CACHE;
 413     while(cache != NULL)
 414         UncacheSID(cache);
 415     UNLOCK_CACHE;
 416 }
 417
 418 /* returns an unsigned int containing the number of seconds in PR_Now() */
 419 PRUint32
 420 ssl_Time(void)
 421 {
 422     PRUint32 myTime;
 423 #if defined(XP_UNIX) || defined(XP_WIN) || defined(_WINDOWS) || defined(XP_BEOS)
 424     myTime = time(NULL);        /* accurate until the year 2038. */
 425 #else
 426     /* portable, but possibly slower */
 427     PRTime now;
 428     PRInt64 ll;
 429
 430     now = PR_Now();
 431     LL_I2L(ll, 1000000L);
 432     LL_DIV(now, now, ll);
 433     LL_L2UI(myTime, now);
 434 #endif
 435     return myTime;
 436 }
 437
 438 void
 439 ssl3_SetSIDSessionTicket(sslSessionID *sid,
 440                          /*in/out*/ NewSessionTicket *newSessionTicket)
 441 {
 442     PORT_Assert(sid);
 443     PORT_Assert(newSessionTicket);
 444
 445     /* if sid->u.ssl3.lock, we are updating an existing entry that is already
 446      * cached or was once cached, so we need to acquire and release the write
 447      * lock. Otherwise, this is a new session that isn't shared with anything
 448      * yet, so no locking is needed.
 449      */
 450     if (sid->u.ssl3.lock) {
 451         NSSRWLock_LockWrite(sid->u.ssl3.lock);
 452
 453         /* A server might have sent us an empty ticket, which has the
 454          * effect of clearing the previously known ticket.
 455          */
 456         if (sid->u.ssl3.locked.sessionTicket.ticket.data) {
 457             SECITEM_FreeItem(&sid->u.ssl3.locked.sessionTicket.ticket,
 458                              PR_FALSE);
 459         }
 460     }
 461
 462     PORT_Assert(!sid->u.ssl3.locked.sessionTicket.ticket.data);
 463
 464     /* Do a shallow copy, moving the ticket data. */
 465     sid->u.ssl3.locked.sessionTicket = *newSessionTicket;
 466     newSessionTicket->ticket.data = NULL;
 467     newSessionTicket->ticket.len = 0;
 468
 469     if (sid->u.ssl3.lock) {
 470         NSSRWLock_UnlockWrite(sid->u.ssl3.lock);
 471     }
 472 }