+ return dest;
+err:
+ SSLerr(SSL_F_SSL_SESSION_DUP, ERR_R_MALLOC_FAILURE);
+ SSL_SESSION_free(dest);
+ return NULL;
+}
+
+const unsigned char *SSL_SESSION_get_id(const SSL_SESSION *s,
+ unsigned int *len)
+{
+ if (len)
+ *len = s->session_id_length;
+ return s->session_id;
+}
+
+unsigned int SSL_SESSION_get_compress_id(const SSL_SESSION *s)
+{
+ return s->compress_meth;
+}
+
+/*
+ * SSLv3/TLSv1 has 32 bytes (256 bits) of session ID space. As such, filling
+ * the ID with random junk repeatedly until we have no conflict is going to
+ * complete in one iteration pretty much "most" of the time (btw:
+ * understatement). So, if it takes us 10 iterations and we still can't avoid
+ * a conflict - well that's a reasonable point to call it quits. Either the
+ * RAND code is broken or someone is trying to open roughly very close to
+ * 2^256 SSL sessions to our server. How you might store that many sessions
+ * is perhaps a more interesting question ...
+ */
+
+#define MAX_SESS_ID_ATTEMPTS 10
+static int def_generate_session_id(const SSL *ssl, unsigned char *id,
+ unsigned int *id_len)
+{
+ unsigned int retry = 0;
+ do
+ if (RAND_bytes(id, *id_len) <= 0)
+ return 0;
+ while (SSL_has_matching_session_id(ssl, id, *id_len) &&
+ (++retry < MAX_SESS_ID_ATTEMPTS)) ;
+ if (retry < MAX_SESS_ID_ATTEMPTS)
+ return 1;
+ /* else - woops a session_id match */
+ /*
+ * XXX We should also check the external cache -- but the probability of
+ * a collision is negligible, and we could not prevent the concurrent
+ * creation of sessions with identical IDs since we currently don't have
+ * means to atomically check whether a session ID already exists and make
+ * a reservation for it if it does not (this problem applies to the
+ * internal cache as well).
+ */
+ return 0;
+}
+
+int ssl_get_new_session(SSL *s, int session)
+{
+ /* This gets used by clients and servers. */
+
+ unsigned int tmp;
+ SSL_SESSION *ss = NULL;
+ GEN_SESSION_CB cb = def_generate_session_id;
+
+ if ((ss = SSL_SESSION_new()) == NULL)
+ return (0);
+
+ /* If the context has a default timeout, use it */
+ if (s->session_ctx->session_timeout == 0)
+ ss->timeout = SSL_get_default_timeout(s);
+ else
+ ss->timeout = s->session_ctx->session_timeout;
+
+ SSL_SESSION_free(s->session);
+ s->session = NULL;
+
+ if (session) {
+ if (s->version == SSL3_VERSION) {
+ ss->ssl_version = SSL3_VERSION;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else if (s->version == TLS1_VERSION) {
+ ss->ssl_version = TLS1_VERSION;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else if (s->version == TLS1_1_VERSION) {
+ ss->ssl_version = TLS1_1_VERSION;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else if (s->version == TLS1_2_VERSION) {
+ ss->ssl_version = TLS1_2_VERSION;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else if (s->version == DTLS1_BAD_VER) {
+ ss->ssl_version = DTLS1_BAD_VER;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else if (s->version == DTLS1_VERSION) {
+ ss->ssl_version = DTLS1_VERSION;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else if (s->version == DTLS1_2_VERSION) {
+ ss->ssl_version = DTLS1_2_VERSION;
+ ss->session_id_length = SSL3_SSL_SESSION_ID_LENGTH;
+ } else {
+ SSLerr(SSL_F_SSL_GET_NEW_SESSION, SSL_R_UNSUPPORTED_SSL_VERSION);
+ SSL_SESSION_free(ss);
+ return (0);
+ }
+
+ /*-
+ * If RFC5077 ticket, use empty session ID (as server).
+ * Note that:
+ * (a) ssl_get_prev_session() does lookahead into the
+ * ClientHello extensions to find the session ticket.
+ * When ssl_get_prev_session() fails, s3_srvr.c calls
+ * ssl_get_new_session() in ssl3_get_client_hello().
+ * At that point, it has not yet parsed the extensions,
+ * however, because of the lookahead, it already knows
+ * whether a ticket is expected or not.
+ *
+ * (b) s3_clnt.c calls ssl_get_new_session() before parsing
+ * ServerHello extensions, and before recording the session
+ * ID received from the server, so this block is a noop.
+ */
+ if (s->tlsext_ticket_expected) {
+ ss->session_id_length = 0;
+ goto sess_id_done;
+ }
+
+ /* Choose which callback will set the session ID */
+ CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
+ if (s->generate_session_id)
+ cb = s->generate_session_id;
+ else if (s->session_ctx->generate_session_id)
+ cb = s->session_ctx->generate_session_id;
+ CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
+ /* Choose a session ID */
+ tmp = ss->session_id_length;
+ if (!cb(s, ss->session_id, &tmp)) {
+ /* The callback failed */
+ SSLerr(SSL_F_SSL_GET_NEW_SESSION,
+ SSL_R_SSL_SESSION_ID_CALLBACK_FAILED);
+ SSL_SESSION_free(ss);
+ return (0);
+ }
+ /*
+ * Don't allow the callback to set the session length to zero. nor
+ * set it higher than it was.
+ */
+ if (!tmp || (tmp > ss->session_id_length)) {
+ /* The callback set an illegal length */
+ SSLerr(SSL_F_SSL_GET_NEW_SESSION,
+ SSL_R_SSL_SESSION_ID_HAS_BAD_LENGTH);
+ SSL_SESSION_free(ss);
+ return (0);
+ }
+ ss->session_id_length = tmp;
+ /* Finally, check for a conflict */
+ if (SSL_has_matching_session_id(s, ss->session_id,
+ ss->session_id_length)) {
+ SSLerr(SSL_F_SSL_GET_NEW_SESSION, SSL_R_SSL_SESSION_ID_CONFLICT);
+ SSL_SESSION_free(ss);
+ return (0);
+ }
+
+ sess_id_done:
+ if (s->tlsext_hostname) {
+ ss->tlsext_hostname = BUF_strdup(s->tlsext_hostname);
+ if (ss->tlsext_hostname == NULL) {
+ SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_INTERNAL_ERROR);
+ SSL_SESSION_free(ss);
+ return 0;
+ }
+ }
+ } else {
+ ss->session_id_length = 0;
+ }
+
+ if (s->sid_ctx_length > sizeof ss->sid_ctx) {
+ SSLerr(SSL_F_SSL_GET_NEW_SESSION, ERR_R_INTERNAL_ERROR);
+ SSL_SESSION_free(ss);
+ return 0;
+ }
+ memcpy(ss->sid_ctx, s->sid_ctx, s->sid_ctx_length);
+ ss->sid_ctx_length = s->sid_ctx_length;
+ s->session = ss;
+ ss->ssl_version = s->version;
+ ss->verify_result = X509_V_OK;
+
+ return (1);
+}
+
+/*-
+ * ssl_get_prev attempts to find an SSL_SESSION to be used to resume this
+ * connection. It is only called by servers.
+ *
+ * session_id: points at the session ID in the ClientHello. This code will
+ * read past the end of this in order to parse out the session ticket
+ * extension, if any.
+ * len: the length of the session ID.
+ * limit: a pointer to the first byte after the ClientHello.
+ *
+ * Returns:
+ * -1: error
+ * 0: a session may have been found.
+ *
+ * Side effects:
+ * - If a session is found then s->session is pointed at it (after freeing an
+ * existing session if need be) and s->verify_result is set from the session.
+ * - Both for new and resumed sessions, s->tlsext_ticket_expected is set to 1
+ * if the server should issue a new session ticket (to 0 otherwise).
+ */
+int ssl_get_prev_session(SSL *s, unsigned char *session_id, int len,
+ const unsigned char *limit)
+{
+ /* This is used only by servers. */
+
+ SSL_SESSION *ret = NULL;
+ int fatal = 0;
+ int try_session_cache = 1;
+ int r;
+
+ if (len < 0 || len > SSL_MAX_SSL_SESSION_ID_LENGTH)
+ goto err;
+
+ if (session_id + len > limit) {
+ fatal = 1;
+ goto err;
+ }
+
+ if (len == 0)
+ try_session_cache = 0;
+
+ /* sets s->tlsext_ticket_expected */
+ r = tls1_process_ticket(s, session_id, len, limit, &ret);
+ switch (r) {
+ case -1: /* Error during processing */
+ fatal = 1;
+ goto err;
+ case 0: /* No ticket found */
+ case 1: /* Zero length ticket found */
+ break; /* Ok to carry on processing session id. */
+ case 2: /* Ticket found but not decrypted. */
+ case 3: /* Ticket decrypted, *ret has been set. */
+ try_session_cache = 0;
+ break;
+ default:
+ abort();
+ }
+
+ if (try_session_cache &&
+ ret == NULL &&
+ !(s->session_ctx->session_cache_mode &
+ SSL_SESS_CACHE_NO_INTERNAL_LOOKUP)) {
+ SSL_SESSION data;
+ data.ssl_version = s->version;
+ data.session_id_length = len;
+ if (len == 0)
+ return 0;
+ memcpy(data.session_id, session_id, len);
+ CRYPTO_r_lock(CRYPTO_LOCK_SSL_CTX);
+ ret = lh_SSL_SESSION_retrieve(s->session_ctx->sessions, &data);
+ if (ret != NULL) {
+ /* don't allow other threads to steal it: */
+ CRYPTO_add(&ret->references, 1, CRYPTO_LOCK_SSL_SESSION);
+ }
+ CRYPTO_r_unlock(CRYPTO_LOCK_SSL_CTX);
+ if (ret == NULL)
+ s->session_ctx->stats.sess_miss++;
+ }
+
+ if (try_session_cache &&
+ ret == NULL && s->session_ctx->get_session_cb != NULL) {
+ int copy = 1;
+
+ if ((ret = s->session_ctx->get_session_cb(s, session_id, len, ©))) {
+ s->session_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);
+
+ /*
+ * Add the externally cached session to the internal cache as
+ * well if and only if we are supposed to.
+ */
+ if (!
+ (s->session_ctx->session_cache_mode &
+ SSL_SESS_CACHE_NO_INTERNAL_STORE)) {
+ /*
+ * The following should not return 1, otherwise, things are
+ * very strange
+ */
+ if (SSL_CTX_add_session(s->session_ctx, ret))
+ goto err;
+ }
+ }
+ }
+
+ if (ret == NULL)
+ goto err;
+
+ /* Now ret is non-NULL and we own one of its reference counts. */
+
+ if (ret->sid_ctx_length != s->sid_ctx_length
+ || memcmp(ret->sid_ctx, s->sid_ctx, ret->sid_ctx_length)) {
+ /*
+ * We have the session requested by the client, but we don't want to
+ * use it in this context.
+ */
+ goto err; /* treat like cache miss */
+ }
+
+ if ((s->verify_mode & SSL_VERIFY_PEER) && s->sid_ctx_length == 0) {
+ /*
+ * We can't be sure if this session is being used out of context,
+ * which is especially important for SSL_VERIFY_PEER. The application
+ * should have used SSL[_CTX]_set_session_id_context. For this error
+ * case, we generate an error instead of treating the event like a
+ * cache miss (otherwise it would be easy for applications to
+ * effectively disable the session cache by accident without anyone
+ * noticing).
+ */
+
+ SSLerr(SSL_F_SSL_GET_PREV_SESSION,
+ SSL_R_SESSION_ID_CONTEXT_UNINITIALIZED);
+ fatal = 1;
+ goto err;
+ }
+
+ if (ret->cipher == NULL) {
+ unsigned char buf[5], *p;
+ unsigned long l;
+
+ p = buf;
+ l = ret->cipher_id;
+ l2n(l, p);
+ if ((ret->ssl_version >> 8) >= SSL3_VERSION_MAJOR)
+ ret->cipher = ssl_get_cipher_by_char(s, &(buf[2]));
+ else
+ ret->cipher = ssl_get_cipher_by_char(s, &(buf[1]));
+ if (ret->cipher == NULL)
+ goto err;
+ }
+
+ if (ret->timeout < (long)(time(NULL) - ret->time)) { /* timeout */
+ s->session_ctx->stats.sess_timeout++;
+ if (try_session_cache) {
+ /* session was from the cache, so remove it */
+ SSL_CTX_remove_session(s->session_ctx, ret);
+ }
+ goto err;
+ }
+
+ s->session_ctx->stats.sess_hit++;
+
+ SSL_SESSION_free(s->session);
+ s->session = ret;
+ s->verify_result = s->session->verify_result;
+ return 1;