+ }
+ }
+
+/* Since the server cache lookup is done early on in the processing of the
+ * ClientHello, and other operations depend on the result, we need to handle
+ * any TLS session ticket extension at the same time.
+ *
+ * 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.
+ * ret: (output) on return, if a ticket was decrypted, then this is set to
+ * point to the resulting session.
+ *
+ * If s->tls_session_secret_cb is set then we are expecting a pre-shared key
+ * ciphersuite, in which case we have no use for session tickets and one will
+ * never be decrypted, nor will s->tlsext_ticket_expected be set to 1.
+ *
+ * Returns:
+ * -1: fatal error, either from parsing or decrypting the ticket.
+ * 0: no ticket was found (or was ignored, based on settings).
+ * 1: a zero length extension was found, indicating that the client supports
+ * session tickets but doesn't currently have one to offer.
+ * 2: either s->tls_session_secret_cb was set, or a ticket was offered but
+ * couldn't be decrypted because of a non-fatal error.
+ * 3: a ticket was successfully decrypted and *ret was set.
+ *
+ * Side effects:
+ * Sets s->tlsext_ticket_expected to 1 if the server will have to issue
+ * a new session ticket to the client because the client indicated support
+ * (and s->tls_session_secret_cb is NULL) but the client either doesn't have
+ * a session ticket or we couldn't use the one it gave us, or if
+ * s->ctx->tlsext_ticket_key_cb asked to renew the client's ticket.
+ * Otherwise, s->tlsext_ticket_expected is set to 0.
+ */
+int tls1_process_ticket(SSL *s, unsigned char *session_id, int len,
+ const unsigned char *limit, SSL_SESSION **ret)
+ {
+ /* Point after session ID in client hello */
+ const unsigned char *p = session_id + len;
+ unsigned short i;
+
+ *ret = NULL;
+ s->tlsext_ticket_expected = 0;
+
+ /* If tickets disabled behave as if no ticket present
+ * to permit stateful resumption.
+ */
+ if (SSL_get_options(s) & SSL_OP_NO_TICKET)
+ return 0;
+ if ((s->version <= SSL3_VERSION) || !limit)
+ return 0;
+ if (p >= limit)
+ return -1;
+ /* Skip past DTLS cookie */
+ if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER)
+ {
+ i = *(p++);
+ p+= i;
+ if (p >= limit)
+ return -1;
+ }
+ /* Skip past cipher list */
+ n2s(p, i);
+ p+= i;
+ if (p >= limit)
+ return -1;
+ /* Skip past compression algorithm list */
+ i = *(p++);
+ p += i;
+ if (p > limit)
+ return -1;
+ /* Now at start of extensions */
+ if ((p + 2) >= limit)
+ return 0;
+ n2s(p, i);
+ while ((p + 4) <= limit)
+ {
+ unsigned short type, size;
+ n2s(p, type);
+ n2s(p, size);
+ if (p + size > limit)
+ return 0;
+ if (type == TLSEXT_TYPE_session_ticket)
+ {
+ int r;
+ if (size == 0)
+ {
+ /* The client will accept a ticket but doesn't
+ * currently have one. */
+ s->tlsext_ticket_expected = 1;
+ return 1;
+ }
+ if (s->tls_session_secret_cb)
+ {
+ /* Indicate that the ticket couldn't be
+ * decrypted rather than generating the session
+ * from ticket now, trigger abbreviated
+ * handshake based on external mechanism to
+ * calculate the master secret later. */
+ return 2;
+ }
+ r = tls_decrypt_ticket(s, p, size, session_id, len, ret);
+ switch (r)
+ {
+ case 2: /* ticket couldn't be decrypted */
+ s->tlsext_ticket_expected = 1;
+ return 2;
+ case 3: /* ticket was decrypted */
+ return r;
+ case 4: /* ticket decrypted but need to renew */
+ s->tlsext_ticket_expected = 1;
+ return 3;
+ default: /* fatal error */
+ return -1;
+ }
+ }
+ p += size;
+ }
+ return 0;
+ }
+
+/* tls_decrypt_ticket attempts to decrypt a session ticket.
+ *
+ * etick: points to the body of the session ticket extension.
+ * eticklen: the length of the session tickets extenion.
+ * sess_id: points at the session ID.
+ * sesslen: the length of the session ID.
+ * psess: (output) on return, if a ticket was decrypted, then this is set to
+ * point to the resulting session.
+ *
+ * Returns:
+ * -1: fatal error, either from parsing or decrypting the ticket.
+ * 2: the ticket couldn't be decrypted.
+ * 3: a ticket was successfully decrypted and *psess was set.
+ * 4: same as 3, but the ticket needs to be renewed.
+ */
+static int tls_decrypt_ticket(SSL *s, const unsigned char *etick, int eticklen,
+ const unsigned char *sess_id, int sesslen,
+ SSL_SESSION **psess)
+ {
+ SSL_SESSION *sess;
+ unsigned char *sdec;
+ const unsigned char *p;
+ int slen, mlen, renew_ticket = 0;
+ unsigned char tick_hmac[EVP_MAX_MD_SIZE];
+ HMAC_CTX hctx;
+ EVP_CIPHER_CTX ctx;
+ SSL_CTX *tctx = s->initial_ctx;
+ /* Need at least keyname + iv + some encrypted data */
+ if (eticklen < 48)
+ return 2;
+ /* Initialize session ticket encryption and HMAC contexts */
+ HMAC_CTX_init(&hctx);
+ EVP_CIPHER_CTX_init(&ctx);
+ if (tctx->tlsext_ticket_key_cb)
+ {
+ unsigned char *nctick = (unsigned char *)etick;
+ int rv = tctx->tlsext_ticket_key_cb(s, nctick, nctick + 16,
+ &ctx, &hctx, 0);
+ if (rv < 0)
+ return -1;
+ if (rv == 0)
+ return 2;
+ if (rv == 2)
+ renew_ticket = 1;
+ }
+ else
+ {
+ /* Check key name matches */
+ if (memcmp(etick, tctx->tlsext_tick_key_name, 16))
+ return 2;
+ HMAC_Init_ex(&hctx, tctx->tlsext_tick_hmac_key, 16,
+ tlsext_tick_md(), NULL);
+ EVP_DecryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL,
+ tctx->tlsext_tick_aes_key, etick + 16);
+ }
+ /* Attempt to process session ticket, first conduct sanity and
+ * integrity checks on ticket.
+ */
+ mlen = HMAC_size(&hctx);
+ if (mlen < 0)
+ {
+ EVP_CIPHER_CTX_cleanup(&ctx);
+ return -1;
+ }
+ eticklen -= mlen;
+ /* Check HMAC of encrypted ticket */
+ HMAC_Update(&hctx, etick, eticklen);
+ HMAC_Final(&hctx, tick_hmac, NULL);
+ HMAC_CTX_cleanup(&hctx);
+ if (memcmp(tick_hmac, etick + eticklen, mlen))
+ return 2;
+ /* Attempt to decrypt session data */
+ /* Move p after IV to start of encrypted ticket, update length */
+ p = etick + 16 + EVP_CIPHER_CTX_iv_length(&ctx);
+ eticklen -= 16 + EVP_CIPHER_CTX_iv_length(&ctx);
+ sdec = OPENSSL_malloc(eticklen);
+ if (!sdec)
+ {
+ EVP_CIPHER_CTX_cleanup(&ctx);
+ return -1;
+ }
+ EVP_DecryptUpdate(&ctx, sdec, &slen, p, eticklen);
+ if (EVP_DecryptFinal(&ctx, sdec + slen, &mlen) <= 0)
+ return 2;
+ slen += mlen;
+ EVP_CIPHER_CTX_cleanup(&ctx);
+ p = sdec;
+
+ sess = d2i_SSL_SESSION(NULL, &p, slen);
+ OPENSSL_free(sdec);
+ if (sess)
+ {
+ /* The session ID, if non-empty, is used by some clients to
+ * detect that the ticket has been accepted. So we copy it to
+ * the session structure. If it is empty set length to zero
+ * as required by standard.
+ */
+ if (sesslen)
+ memcpy(sess->session_id, sess_id, sesslen);
+ sess->session_id_length = sesslen;
+ *psess = sess;
+ if (renew_ticket)
+ return 4;
+ else
+ return 3;
+ }
+ ERR_clear_error();
+ /* For session parse failure, indicate that we need to send a new
+ * ticket. */
+ return 2;
+ }
+
+/* Tables to translate from NIDs to TLS v1.2 ids */
+
+typedef struct
+ {
+ int nid;
+ int id;
+ } tls12_lookup;
+
+static tls12_lookup tls12_md[] = {
+#ifndef OPENSSL_NO_MD5
+ {NID_md5, TLSEXT_hash_md5},
+#endif
+#ifndef OPENSSL_NO_SHA
+ {NID_sha1, TLSEXT_hash_sha1},
+#endif
+#ifndef OPENSSL_NO_SHA256
+ {NID_sha224, TLSEXT_hash_sha224},
+ {NID_sha256, TLSEXT_hash_sha256},
+#endif
+#ifndef OPENSSL_NO_SHA512
+ {NID_sha384, TLSEXT_hash_sha384},
+ {NID_sha512, TLSEXT_hash_sha512}
+#endif
+};
+
+static tls12_lookup tls12_sig[] = {
+#ifndef OPENSSL_NO_RSA
+ {EVP_PKEY_RSA, TLSEXT_signature_rsa},
+#endif
+#ifndef OPENSSL_NO_RSA
+ {EVP_PKEY_DSA, TLSEXT_signature_dsa},
+#endif
+#ifndef OPENSSL_NO_ECDSA
+ {EVP_PKEY_EC, TLSEXT_signature_ecdsa}
+#endif
+};
+
+static int tls12_find_id(int nid, tls12_lookup *table, size_t tlen)
+ {
+ size_t i;
+ for (i = 0; i < tlen; i++)
+ {
+ if (table[i].nid == nid)
+ return table[i].id;
+ }
+ return -1;
+ }
+#if 0
+static int tls12_find_nid(int id, tls12_lookup *table, size_t tlen)
+ {
+ size_t i;
+ for (i = 0; i < tlen; i++)
+ {
+ if (table[i].id == id)
+ return table[i].nid;
+ }
+ return -1;
+ }
+#endif
+
+int tls12_get_sigandhash(unsigned char *p, const EVP_PKEY *pk, const EVP_MD *md)
+ {
+ int sig_id, md_id;
+ if (!md)
+ return 0;
+ md_id = tls12_find_id(EVP_MD_type(md), tls12_md,
+ sizeof(tls12_md)/sizeof(tls12_lookup));
+ if (md_id == -1)
+ return 0;
+ sig_id = tls12_get_sigid(pk);
+ if (sig_id == -1)
+ return 0;
+ p[0] = (unsigned char)md_id;
+ p[1] = (unsigned char)sig_id;
+ return 1;
+ }
+
+int tls12_get_sigid(const EVP_PKEY *pk)
+ {
+ return tls12_find_id(pk->type, tls12_sig,
+ sizeof(tls12_sig)/sizeof(tls12_lookup));
+ }
+
+const EVP_MD *tls12_get_hash(unsigned char hash_alg)
+ {
+ switch(hash_alg)
+ {
+#ifndef OPENSSL_NO_MD5
+ case TLSEXT_hash_md5:
+#ifdef OPENSSL_FIPS
+ if (FIPS_mode())
+ return NULL;
+#endif
+ return EVP_md5();
+#endif
+#ifndef OPENSSL_NO_SHA
+ case TLSEXT_hash_sha1:
+ return EVP_sha1();
+#endif
+#ifndef OPENSSL_NO_SHA256
+ case TLSEXT_hash_sha224:
+ return EVP_sha224();
+
+ case TLSEXT_hash_sha256:
+ return EVP_sha256();
+#endif
+#ifndef OPENSSL_NO_SHA512
+ case TLSEXT_hash_sha384:
+ return EVP_sha384();
+
+ case TLSEXT_hash_sha512:
+ return EVP_sha512();
+#endif
+ default:
+ return NULL;
+
+ }
+ }
+
+/* Set preferred digest for each key type */
+
+int tls1_process_sigalgs(SSL *s, const unsigned char *data, int dsize)
+ {
+ int i, idx;
+ const EVP_MD *md;
+ CERT *c = s->cert;
+ /* Extension ignored for TLS versions below 1.2 */
+ if (TLS1_get_version(s) < TLS1_2_VERSION)
+ return 1;
+ /* Should never happen */
+ if (!c)
+ return 0;
+
+ c->pkeys[SSL_PKEY_DSA_SIGN].digest = NULL;
+ c->pkeys[SSL_PKEY_RSA_SIGN].digest = NULL;
+ c->pkeys[SSL_PKEY_RSA_ENC].digest = NULL;
+ c->pkeys[SSL_PKEY_ECC].digest = NULL;
+
+ for (i = 0; i < dsize; i += 2)
+ {
+ unsigned char hash_alg = data[i], sig_alg = data[i+1];
+
+ switch(sig_alg)
+ {
+#ifndef OPENSSL_NO_RSA
+ case TLSEXT_signature_rsa:
+ idx = SSL_PKEY_RSA_SIGN;
+ break;
+#endif
+#ifndef OPENSSL_NO_DSA
+ case TLSEXT_signature_dsa:
+ idx = SSL_PKEY_DSA_SIGN;
+ break;
+#endif
+#ifndef OPENSSL_NO_ECDSA
+ case TLSEXT_signature_ecdsa:
+ idx = SSL_PKEY_ECC;
+ break;
+#endif
+ default:
+ continue;
+ }
+
+ if (c->pkeys[idx].digest == NULL)
+ {
+ md = tls12_get_hash(hash_alg);
+ if (md)
+ {
+ c->pkeys[idx].digest = md;
+ if (idx == SSL_PKEY_RSA_SIGN)
+ c->pkeys[SSL_PKEY_RSA_ENC].digest = md;
+ }
+ }
+
+ }
+
+
+ /* Set any remaining keys to default values. NOTE: if alg is not
+ * supported it stays as NULL.
+ */
+#ifndef OPENSSL_NO_DSA
+ if (!c->pkeys[SSL_PKEY_DSA_SIGN].digest)
+ c->pkeys[SSL_PKEY_DSA_SIGN].digest = EVP_dss1();
+#endif
+#ifndef OPENSSL_NO_RSA
+ if (!c->pkeys[SSL_PKEY_RSA_SIGN].digest)
+ {
+ c->pkeys[SSL_PKEY_RSA_SIGN].digest = EVP_sha1();
+ c->pkeys[SSL_PKEY_RSA_ENC].digest = EVP_sha1();
+ }
+#endif
+#ifndef OPENSSL_NO_ECDSA
+ if (!c->pkeys[SSL_PKEY_ECC].digest)
+ c->pkeys[SSL_PKEY_ECC].digest = EVP_ecdsa();
+#endif
+ return 1;
+ }
+
+#endif
+
+#ifndef OPENSSL_NO_HEARTBEATS
+int
+tls1_process_heartbeat(SSL *s)
+ {
+ unsigned char *p = &s->s3->rrec.data[0], *pl;
+ unsigned short hbtype;
+ unsigned int payload;
+ unsigned int padding = 16; /* Use minimum padding */
+
+ /* Read type and payload length first */
+ hbtype = *p++;
+ n2s(p, payload);
+ pl = p;
+
+ if (s->msg_callback)
+ s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT,
+ &s->s3->rrec.data[0], s->s3->rrec.length,
+ s, s->msg_callback_arg);
+
+ if (hbtype == TLS1_HB_REQUEST)
+ {
+ unsigned char *buffer, *bp;
+ int r;
+
+ /* Allocate memory for the response, size is 1 bytes
+ * message type, plus 2 bytes payload length, plus
+ * payload, plus padding
+ */
+ buffer = OPENSSL_malloc(1 + 2 + payload + padding);
+ bp = buffer;
+
+ /* Enter response type, length and copy payload */
+ *bp++ = TLS1_HB_RESPONSE;
+ s2n(payload, bp);
+ memcpy(bp, pl, payload);
+
+ r = ssl3_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, 3 + payload + padding);
+
+ if (r >= 0 && s->msg_callback)
+ s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
+ buffer, 3 + payload + padding,
+ s, s->msg_callback_arg);
+
+ OPENSSL_free(buffer);
+
+ if (r < 0)
+ return r;
+ }
+ else if (hbtype == TLS1_HB_RESPONSE)
+ {
+ unsigned int seq;
+
+ /* We only send sequence numbers (2 bytes unsigned int),
+ * and 16 random bytes, so we just try to read the
+ * sequence number */
+ n2s(pl, seq);
+
+ if (payload == 18 && seq == s->tlsext_hb_seq)
+ {
+ s->tlsext_hb_seq++;
+ s->tlsext_hb_pending = 0;
+ }
+ }
+
+ return 0;
+ }
+
+int
+tls1_heartbeat(SSL *s)
+ {
+ unsigned char *buf, *p;
+ int ret;
+ unsigned int payload = 18; /* Sequence number + random bytes */
+ unsigned int padding = 16; /* Use minimum padding */
+
+ /* Only send if peer supports and accepts HB requests... */
+ if (!(s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED) ||
+ s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS)
+ {
+ SSLerr(SSL_F_TLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT);
+ return -1;
+ }
+
+ /* ...and there is none in flight yet... */
+ if (s->tlsext_hb_pending)
+ {
+ SSLerr(SSL_F_TLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PENDING);
+ return -1;
+ }
+
+ /* ...and no handshake in progress. */
+ if (SSL_in_init(s) || s->in_handshake)
+ {
+ SSLerr(SSL_F_TLS1_HEARTBEAT,SSL_R_UNEXPECTED_MESSAGE);
+ return -1;
+ }
+
+ /* Check if padding is too long, payload and padding
+ * must not exceed 2^14 - 3 = 16381 bytes in total.
+ */
+ OPENSSL_assert(payload + padding <= 16381);
+
+ /* Create HeartBeat message, we just use a sequence number
+ * as payload to distuingish different messages and add
+ * some random stuff.
+ * - Message Type, 1 byte
+ * - Payload Length, 2 bytes (unsigned int)
+ * - Payload, the sequence number (2 bytes uint)
+ * - Payload, random bytes (16 bytes uint)
+ * - Padding
+ */
+ buf = OPENSSL_malloc(1 + 2 + payload + padding);
+ p = buf;
+ /* Message Type */
+ *p++ = TLS1_HB_REQUEST;
+ /* Payload length (18 bytes here) */
+ s2n(payload, p);
+ /* Sequence number */
+ s2n(s->tlsext_hb_seq, p);
+ /* 16 random bytes */
+ RAND_pseudo_bytes(p, 16);
+ p += 16;
+ /* Random padding */
+ RAND_pseudo_bytes(p, padding);
+
+ ret = ssl3_write_bytes(s, TLS1_RT_HEARTBEAT, buf, 3 + payload + padding);
+ if (ret >= 0)
+ {
+ if (s->msg_callback)
+ s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
+ buf, 3 + payload + padding,
+ s, s->msg_callback_arg);
+
+ s->tlsext_hb_pending = 1;
+ }
+
+ OPENSSL_free(buf);
+
+ return ret;