diff options
author | Bodo Möller <bodo@openssl.org> | 1999-05-23 13:07:03 +0000 |
---|---|---|
committer | Bodo Möller <bodo@openssl.org> | 1999-05-23 13:07:03 +0000 |
commit | 8876bc054802b043a3ec95554b6c5873291770be (patch) | |
tree | fab0b1b50fae05f19935fe14f17156a55c6fa75e /ssl | |
parent | 3550ec4f1ff6f259c92a5ef649974a0c8ce851b8 (diff) |
Let ssl_get_prev_session reliably work in multi-threaded settings.
Diffstat (limited to 'ssl')
-rw-r--r-- | ssl/s3_srvr.c | 4 | ||||
-rw-r--r-- | ssl/ssl_sess.c | 67 |
2 files changed, 56 insertions, 15 deletions
diff --git a/ssl/s3_srvr.c b/ssl/s3_srvr.c index 9d2debf00d..e003d88357 100644 --- a/ssl/s3_srvr.c +++ b/ssl/s3_srvr.c @@ -557,7 +557,9 @@ static int ssl3_get_client_hello(SSL *s) { /* previous session */ s->hit=1; } - else + else if (i == -1) + goto err; + else /* i == 0 */ { if (!ssl_get_new_session(s,1)) goto err; diff --git a/ssl/ssl_sess.c b/ssl/ssl_sess.c index 3872b41928..29e6cc16ce 100644 --- a/ssl/ssl_sess.c +++ b/ssl/ssl_sess.c @@ -188,18 +188,21 @@ int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len) /* This is used only by servers. */ SSL_SESSION *ret=NULL,data; + int fatal = 0; /* conn_init();*/ data.ssl_version=s->version; data.session_id_length=len; if (len > SSL_MAX_SSL_SESSION_ID_LENGTH) - return(0); + goto err; memcpy(data.session_id,session_id,len); if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_NO_INTERNAL_LOOKUP)) { CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX); ret=(SSL_SESSION *)lh_retrieve(s->ctx->sessions,(char *)&data); + /* don't allow other threads to steal it: */ + CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION); CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX); } @@ -215,27 +218,52 @@ int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len) { s->ctx->stats.sess_cb_hit++; + /* Increment reference count now if the session callback + * asks us to do so (note that if the session structures + * returned by the callback are shared between threads, + * it must handle the reference count itself [i.e. copy == 0], + * or things won't be thread-safe). */ + if (copy) + CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION); + /* The following should not return 1, otherwise, * things are very strange */ SSL_CTX_add_session(s->ctx,ret); - /* auto free it (decrement reference count now) */ - if (!copy) - SSL_SESSION_free(ret); } - if (ret == NULL) return(0); + if (ret == NULL) + goto err; } + /* Now ret is non-NULL, and we own one of its reference counts. */ + if((s->verify_mode&SSL_VERIFY_PEER) && (!s->sid_ctx_length || ret->sid_ctx_length != s->sid_ctx_length || memcmp(ret->sid_ctx,s->sid_ctx,ret->sid_ctx_length))) { - if (s->sid_ctx_length) - SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT); - else - /* application should have used SSL[_CTX]_set_session_id_context */ + /* We've found the session named by the client, but we don't + * want to use it in this context. */ + + if (s->sid_ctx_length == 0) + { + /* application should have used SSL[_CTX]_set_session_id_context + * -- we could tolerate this and just pretend we never heard + * of this session, but then applications could effectively + * disable the session cache by accident without anyone noticing */ + SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED); - return 0; - } + fatal = 1; + goto err; + } + else + { +#if 0 /* The client cannot always know when a session is not appropriate, + * so we shouldn't generate an error message. */ + + SSLerr(SSL_F_SSL_GET_PREV_SESSION,SSL_R_ATTEMPT_TO_REUSE_SESSION_IN_DIFFERENT_CONTEXT); +#endif + goto err; /* treat like cache miss */ + } + } if (ret->cipher == NULL) { @@ -250,22 +278,25 @@ int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len) else ret->cipher=ssl_get_cipher_by_char(s,&(buf[1])); if (ret->cipher == NULL) - return(0); + goto err; } + +#if 0 /* This is way too late. */ + /* If a thread got the session, then 'swaped', and another got * it and then due to a time-out decided to 'Free' it we could * be in trouble. So I'll increment it now, then double decrement * later - am I speaking rubbish?. */ CRYPTO_add(&ret->references,1,CRYPTO_LOCK_SSL_SESSION); +#endif if ((long)(ret->time+ret->timeout) < (long)time(NULL)) /* timeout */ { s->ctx->stats.sess_timeout++; /* remove it from the cache */ SSL_CTX_remove_session(s->ctx,ret); - SSL_SESSION_free(ret); /* again to actually Free it */ - return(0); + goto err; } s->ctx->stats.sess_hit++; @@ -278,6 +309,14 @@ int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len) SSL_SESSION_free(s->session); s->session=ret; return(1); + + err: + if (ret != NULL) + SSL_SESSION_free(ret); + if (fatal) + return -1; + else + return 0; } int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *c) |