/*
* 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 ssl_sid_timeout = 100;
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 PRCallOnceType lockOnce;
/* FreeSessionCacheLocks is a callback from NSS_RegisterShutdown which destroys
* the session cache locks on shutdown and resets them to their initial
* state. */
static SECStatus
FreeSessionCacheLocks(void* appData, void* nssData)
{
static const PRCallOnceType pristineCallOnce;
SECStatus rv;
if (!cacheLock) {
PORT_SetError(SEC_ERROR_NOT_INITIALIZED);
return SECFailure;
}
PZ_DestroyLock(cacheLock);
cacheLock = NULL;
rv = ssl_FreeSymWrapKeysLock();
if (rv != SECSuccess) {
return rv;
}
lockOnce = pristineCallOnce;
return SECSuccess;
}
/* InitSessionCacheLocks is called, protected by lockOnce, to create the
* session cache locks. */
static PRStatus
InitSessionCacheLocks(void)
{
SECStatus rv;
cacheLock = PZ_NewLock(nssILockCache);
if (cacheLock == NULL) {
return PR_FAILURE;
}
rv = ssl_InitSymWrapKeysLock();
if (rv != SECSuccess) {
PRErrorCode error = PORT_GetError();
PZ_DestroyLock(cacheLock);
cacheLock = NULL;
PORT_SetError(error);
return PR_FAILURE;
}
rv = NSS_RegisterShutdown(FreeSessionCacheLocks, NULL);
PORT_Assert(SECSuccess == rv);
if (SECSuccess != rv) {
return PR_FAILURE;
}
return PR_SUCCESS;
}
SECStatus
ssl_InitSessionCacheLocks(void)
{
return (PR_SUCCESS ==
PR_CallOnce(&lockOnce, InitSessionCacheLocks)) ?
SECSuccess : SECFailure;
}
static void
lock_cache(void)
{
ssl_InitSessionCacheLocks();
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)
{
int i;
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->version < SSL_LIBRARY_VERSION_3_0) {
SECITEM_ZfreeItem(&sid->u.ssl2.masterKey, PR_FALSE);
SECITEM_ZfreeItem(&sid->u.ssl2.cipherArg, PR_FALSE);
} else {
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.originalHandshakeHash.data) {
SECITEM_FreeItem(&sid->u.ssl3.originalHandshakeHash, PR_FALSE);
}
if (sid->u.ssl3.signedCertTimestamps.data) {
SECITEM_FreeItem(&sid->u.ssl3.signedCertTimestamps, PR_FALSE);
}
if (sid->u.ssl3.lock) {
NSSRWLock_Destroy(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);
}
for (i = 0; i < MAX_PEER_CERT_CHAIN_SIZE && sid->peerCertChain[i]; i++) {
CERT_DestroyCertificate(sid->peerCertChain[i]);
}
if (sid->peerCertStatus.items) {
SECITEM_FreeArray(&sid->peerCertStatus, PR_FALSE);
}
if ( sid->localCert ) {
CERT_DestroyCertificate(sid->localCert);
}
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_Time();
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->version < SSL_LIBRARY_VERSION_3_0 ||
sid->u.ssl3.keys.resumable) &&
/* server hostname matches. */
(sid->urlSvrName != NULL) &&
((0 == PORT_Strcmp(urlSvrName, sid->urlSvrName)) ||
((sid->peerCert != NULL) && (SECSuccess ==
CERT_VerifyCertName(sid->peerCert, 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)
{
PRUint32 expirationPeriod;
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;
}
/* XXX should be different trace for version 2 vs. version 3 */
if (sid->version < SSL_LIBRARY_VERSION_3_0) {
expirationPeriod = ssl_sid_timeout;
PRINT_BUF(8, (0, "sessionID:",
sid->u.ssl2.sessionID, sizeof(sid->u.ssl2.sessionID)));
PRINT_BUF(8, (0, "masterKey:",
sid->u.ssl2.masterKey.data, sid->u.ssl2.masterKey.len));
PRINT_BUF(8, (0, "cipherArg:",
sid->u.ssl2.cipherArg.data, sid->u.ssl2.cipherArg.len));
} else {
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;
}
expirationPeriod = ssl3_sid_timeout;
PRINT_BUF(8, (0, "sessionID:",
sid->u.ssl3.sessionID, sid->u.ssl3.sessionIDLength));
sid->u.ssl3.lock = NSSRWLock_New(NSS_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_Time();
if (!sid->expirationTime)
sid->expirationTime = sid->creationTime + expirationPeriod;
/*
* 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 cipher=%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.ssl2.cipherType));
if (zap->version < SSL_LIBRARY_VERSION_3_0) {
PRINT_BUF(8, (0, "sessionID:",
zap->u.ssl2.sessionID, sizeof(zap->u.ssl2.sessionID)));
PRINT_BUF(8, (0, "masterKey:",
zap->u.ssl2.masterKey.data, zap->u.ssl2.masterKey.len));
PRINT_BUF(8, (0, "cipherArg:",
zap->u.ssl2.cipherArg.data, zap->u.ssl2.cipherArg.len));
}
/* 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_Time(void)
{
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;
}
void
ssl3_SetSIDSessionTicket(sslSessionID *sid,
/*in/out*/ NewSessionTicket *newSessionTicket)
{
PORT_Assert(sid);
PORT_Assert(newSessionTicket);
/* 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) {
NSSRWLock_LockWrite(sid->u.ssl3.lock);
/* A server might have sent us an empty ticket, which has the
* effect of clearing the previously known ticket.
*/
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) {
NSSRWLock_UnlockWrite(sid->u.ssl3.lock);
}
}