if (cb != NULL)
cb(s, SSL_CB_HANDSHAKE_START, 1);
- if ((s->version >> 8) != 3) {
+ if ((s->version >> 8 != 3) && s->version != TLS_ANY_VERSION) {
SSLerr(SSL_F_SSL3_ACCEPT, ERR_R_INTERNAL_ERROR);
s->state = SSL_ST_ERR;
return -1;
SSL_COMP *comp = NULL;
#endif
STACK_OF(SSL_CIPHER) *ciphers = NULL;
+ int protverr = 1;
if (s->state == SSL3_ST_SR_CLNT_HELLO_C && !s->first_packet)
goto retry_cert;
s->first_packet = 0;
d = p = (unsigned char *)s->init_msg;
- /*
- * 2 bytes for client version, SSL3_RANDOM_SIZE bytes for random, 1 byte
- * for session id length
- */
- if (n < 2 + SSL3_RANDOM_SIZE + 1) {
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
- goto f_err;
+ /* First lets get s->client_version set correctly */
+ if (!s->read_hash && !s->enc_read_ctx
+ && RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
+ if (n < MIN_SSL2_RECORD_LEN) {
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_RECORD_LENGTH_MISMATCH);
+ al = SSL_AD_DECODE_ERROR;
+ goto f_err;
+ }
+ /*-
+ * An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
+ * header is sent directly on the wire, not wrapped as a TLS
+ * record. Our record layer just processes the message length and passes
+ * the rest right through. Its format is:
+ * Byte Content
+ * 0-1 msg_length - decoded by the record layer
+ * 2 msg_type - s->init_msg points here
+ * 3-4 version
+ * 5-6 cipher_spec_length
+ * 7-8 session_id_length
+ * 9-10 challenge_length
+ * ... ...
+ */
+
+ if (p[0] != SSL2_MT_CLIENT_HELLO) {
+ /*
+ * Should never happen. We should have tested this in the record
+ * layer in order to have determined that this is a SSLv2 record
+ * in the first place
+ */
+ al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
+ goto f_err;
+ }
+
+ if ((p[1] == 0x00) && (p[2] == 0x02)) {
+ /* This is real SSLv2. We don't support it. */
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
+ goto err;
+ } else if (p[1] == SSL3_VERSION_MAJOR) {
+ /* SSLv3/TLS */
+ s->client_version = (((int)p[1]) << 8) | (int)p[2];
+ } else {
+ /* No idea what protocol this is */
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
+ goto err;
+ }
+ } else {
+ /*
+ * 2 bytes for client version, SSL3_RANDOM_SIZE bytes for random, 1 byte
+ * for session id length
+ */
+ if (n < 2 + SSL3_RANDOM_SIZE + 1) {
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
+ goto f_err;
+ }
+
+ /*
+ * use version from inside client hello, not from record header (may
+ * differ: see RFC 2246, Appendix E, second paragraph)
+ */
+ s->client_version = (((int)p[0]) << 8) | (int)p[1];
}
- /*
- * use version from inside client hello, not from record header (may
- * differ: see RFC 2246, Appendix E, second paragraph)
- */
- s->client_version = (((int)p[0]) << 8) | (int)p[1];
- p += 2;
-
- if (SSL_IS_DTLS(s) ? (s->client_version > s->version &&
- s->method->version != DTLS_ANY_VERSION)
- : (s->client_version < s->version)) {
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_WRONG_VERSION_NUMBER);
- if ((s->client_version >> 8) == SSL3_VERSION_MAJOR &&
- !s->enc_write_ctx && !s->write_hash) {
+ /* Do SSL/TLS version negotiation if applicable */
+ if (!SSL_IS_DTLS(s)) {
+ if (s->version != TLS_ANY_VERSION) {
+ if (s->client_version >= s->version
+ && (((s->client_version >> 8) & 0xff) == SSL3_VERSION_MAJOR)) {
+ protverr = 0;
+ }
+ } else {
+ /*
+ * We already know that this is an SSL3_VERSION_MAJOR protocol,
+ * so we're just testing the minor versions here
+ */
+ switch(s->client_version) {
+ default:
+ case TLS1_2_VERSION:
+ if(!(s->options & SSL_OP_NO_TLSv1_2)) {
+ s->version = TLS1_2_VERSION;
+ s->method = TLSv1_2_server_method();
+ protverr = 0;
+ break;
+ }
+ /* Deliberately fall through */
+ case TLS1_1_VERSION:
+ if(!(s->options & SSL_OP_NO_TLSv1_1)) {
+ s->version = TLS1_1_VERSION;
+ s->method = TLSv1_1_server_method();
+ protverr = 0;
+ break;
+ }
+ /* Deliberately fall through */
+ case TLS1_VERSION:
+ if(!(s->options & SSL_OP_NO_TLSv1)) {
+ s->version = TLS1_VERSION;
+ s->method = TLSv1_server_method();
+ protverr = 0;
+ break;
+ }
+ /* Deliberately fall through */
+ case SSL3_VERSION:
+ if(!(s->options & SSL_OP_NO_SSLv3)) {
+ s->version = SSL3_VERSION;
+ s->method = SSLv3_server_method();
+ protverr = 0;
+ break;
+ }
+ }
+ }
+ } else if (((s->client_version >> 8) & 0xff) == DTLS1_VERSION_MAJOR &&
+ (s->client_version <= s->version
+ || s->method->version == DTLS_ANY_VERSION)) {
+ /*
+ * For DTLS we just check versions are potentially compatible. Version
+ * negotiation comes later.
+ */
+ protverr = 0;
+ }
+
+ if (protverr) {
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
+ if ((!s->enc_write_ctx && !s->write_hash)) {
/*
* similar to ssl3_get_record, send alert using remote version
* number
goto f_err;
}
- /*
- * If we require cookies and this ClientHello doesn't contain one, just
- * return since we do not want to allocate any memory yet. So check
- * cookie length...
- */
- if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
- unsigned int session_length, cookie_length;
+ if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
+ /*
+ * Handle an SSLv2 backwards compatible ClientHello
+ * Note, this is only for SSLv3+ using the backward compatible format.
+ * Real SSLv2 is not supported, and is rejected above.
+ */
+ unsigned int csl, sil, cl;
- session_length = *(p + SSL3_RANDOM_SIZE);
+ p += 3;
+ n2s(p, csl);
+ n2s(p, sil);
+ n2s(p, cl);
- if (p + SSL3_RANDOM_SIZE + session_length + 1 >= d + n) {
+ if (csl + sil + cl + MIN_SSL2_RECORD_LEN != (unsigned int) n) {
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_RECORD_LENGTH_MISMATCH);
al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
goto f_err;
}
- cookie_length = *(p + SSL3_RANDOM_SIZE + session_length + 1);
-
- if (cookie_length == 0)
- return 1;
- }
- /* load the client random */
- memcpy(s->s3->client_random, p, SSL3_RANDOM_SIZE);
- p += SSL3_RANDOM_SIZE;
+ if (csl == 0) {
+ /* we need at least one cipher */
+ al = SSL_AD_ILLEGAL_PARAMETER;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_NO_CIPHERS_SPECIFIED);
+ goto f_err;
+ }
- /* get the session-id */
- j = *(p++);
+ if (ssl_bytes_to_cipher_list(s, p, csl, &(ciphers), 1) == NULL) {
+ goto err;
+ }
- if (p + j > d + n) {
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
- goto f_err;
- }
+ /*
+ * Ignore any session id. We don't allow resumption in a backwards
+ * compatible ClientHello
+ */
+ s->hit = 0;
- s->hit = 0;
- /*
- * Versions before 0.9.7 always allow clients to resume sessions in
- * renegotiation. 0.9.7 and later allow this by default, but optionally
- * ignore resumption requests with flag
- * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
- * than a change to default behavior so that applications relying on this
- * for security won't even compile against older library versions).
- * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to
- * request renegotiation but not a new session (s->new_session remains
- * unset): for servers, this essentially just means that the
- * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be ignored.
- */
- if ((s->new_session
- && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
if (!ssl_get_new_session(s, 1))
goto err;
+
+ /* Load the client random */
+ i = (cl > SSL3_RANDOM_SIZE) ? SSL3_RANDOM_SIZE : cl;
+ memset(s->s3->client_random, 0, SSL3_RANDOM_SIZE);
+ memcpy(s->s3->client_random, &(p[csl + sil]), i);
+
+ /* Set p to end of packet to ensure we don't look for extensions */
+ p = d + n;
+
+ /* No compression, so set i to 0 */
+ i = 0;
} else {
- i = ssl_get_prev_session(s, p, j, d + n);
+ /* If we get here we've got SSLv3+ in an SSLv3+ record */
+
+ p += 2;
+
/*
- * Only resume if the session's version matches the negotiated
- * version.
- * RFC 5246 does not provide much useful advice on resumption
- * with a different protocol version. It doesn't forbid it but
- * the sanity of such behaviour would be questionable.
- * In practice, clients do not accept a version mismatch and
- * will abort the handshake with an error.
+ * If we require cookies and this ClientHello doesn't contain one, just
+ * return since we do not want to allocate any memory yet. So check
+ * cookie length...
*/
- if (i == 1 && s->version == s->session->ssl_version) { /* previous
- * session */
- s->hit = 1;
- } else if (i == -1)
- goto err;
- else { /* i == 0 */
+ if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
+ unsigned int session_length, cookie_length;
- if (!ssl_get_new_session(s, 1))
- goto err;
- }
- }
+ session_length = *(p + SSL3_RANDOM_SIZE);
- p += j;
+ if (p + SSL3_RANDOM_SIZE + session_length + 1 >= d + n) {
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
+ goto f_err;
+ }
+ cookie_length = *(p + SSL3_RANDOM_SIZE + session_length + 1);
- if (SSL_IS_DTLS(s)) {
- /* cookie stuff */
- if (p + 1 > d + n) {
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
- goto f_err;
+ if (cookie_length == 0)
+ return 1;
}
- cookie_len = *(p++);
- if (p + cookie_len > d + n) {
+ /* load the client random */
+ memcpy(s->s3->client_random, p, SSL3_RANDOM_SIZE);
+ p += SSL3_RANDOM_SIZE;
+
+ /* get the session-id */
+ j = *(p++);
+
+ if (p + j > d + n) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
goto f_err;
}
+ s->hit = 0;
/*
- * The ClientHello may contain a cookie even if the
- * HelloVerify message has not been sent--make sure that it
- * does not cause an overflow.
+ * Versions before 0.9.7 always allow clients to resume sessions in
+ * renegotiation. 0.9.7 and later allow this by default, but optionally
+ * ignore resumption requests with flag
+ * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag rather
+ * than a change to default behavior so that applications relying on
+ * this for security won't even compile against older library versions).
+ * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() to
+ * request renegotiation but not a new session (s->new_session remains
+ * unset): for servers, this essentially just means that the
+ * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be
+ * ignored.
*/
- if (cookie_len > sizeof(s->d1->rcvd_cookie)) {
- /* too much data */
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
- goto f_err;
+ if ((s->new_session
+ && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
+ if (!ssl_get_new_session(s, 1))
+ goto err;
+ } else {
+ i = ssl_get_prev_session(s, p, j, d + n);
+ /*
+ * Only resume if the session's version matches the negotiated
+ * version.
+ * RFC 5246 does not provide much useful advice on resumption
+ * with a different protocol version. It doesn't forbid it but
+ * the sanity of such behaviour would be questionable.
+ * In practice, clients do not accept a version mismatch and
+ * will abort the handshake with an error.
+ */
+ if (i == 1 && s->version == s->session->ssl_version) {
+ /* previous session */
+ s->hit = 1;
+ } else if (i == -1)
+ goto err;
+ else {
+ /* i == 0 */
+ if (!ssl_get_new_session(s, 1))
+ goto err;
+ }
}
- /* verify the cookie if appropriate option is set. */
- if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && cookie_len > 0) {
- memcpy(s->d1->rcvd_cookie, p, cookie_len);
+ p += j;
- if (s->ctx->app_verify_cookie_cb != NULL) {
- if (s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie,
- cookie_len) == 0) {
- al = SSL_AD_HANDSHAKE_FAILURE;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
- SSL_R_COOKIE_MISMATCH);
- goto f_err;
- }
- /* else cookie verification succeeded */
- }
- /* default verification */
- else if (memcmp(s->d1->rcvd_cookie, s->d1->cookie,
- s->d1->cookie_len) != 0) {
- al = SSL_AD_HANDSHAKE_FAILURE;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
+ if (SSL_IS_DTLS(s)) {
+ /* cookie stuff */
+ if (p + 1 > d + n) {
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
goto f_err;
}
- /* Set to -2 so if successful we return 2 */
- ret = -2;
- }
+ cookie_len = *(p++);
- p += cookie_len;
- if (s->method->version == DTLS_ANY_VERSION) {
- /* Select version to use */
- if (s->client_version <= DTLS1_2_VERSION &&
- !(s->options & SSL_OP_NO_DTLSv1_2)) {
- s->version = DTLS1_2_VERSION;
- s->method = DTLSv1_2_server_method();
- } else if (tls1_suiteb(s)) {
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
- SSL_R_ONLY_DTLS_1_2_ALLOWED_IN_SUITEB_MODE);
- s->version = s->client_version;
- al = SSL_AD_PROTOCOL_VERSION;
+ if (p + cookie_len > d + n) {
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
goto f_err;
- } else if (s->client_version <= DTLS1_VERSION &&
- !(s->options & SSL_OP_NO_DTLSv1)) {
- s->version = DTLS1_VERSION;
- s->method = DTLSv1_server_method();
- } else {
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
- SSL_R_WRONG_VERSION_NUMBER);
- s->version = s->client_version;
- al = SSL_AD_PROTOCOL_VERSION;
+ }
+
+ /*
+ * The ClientHello may contain a cookie even if the
+ * HelloVerify message has not been sent--make sure that it
+ * does not cause an overflow.
+ */
+ if (cookie_len > sizeof(s->d1->rcvd_cookie)) {
+ /* too much data */
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
goto f_err;
}
- s->session->ssl_version = s->version;
+
+ /* verify the cookie if appropriate option is set. */
+ if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)
+ && cookie_len > 0) {
+ memcpy(s->d1->rcvd_cookie, p, cookie_len);
+
+ if (s->ctx->app_verify_cookie_cb != NULL) {
+ if (s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie,
+ cookie_len) == 0) {
+ al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
+ SSL_R_COOKIE_MISMATCH);
+ goto f_err;
+ }
+ /* else cookie verification succeeded */
+ }
+ /* default verification */
+ else if (memcmp(s->d1->rcvd_cookie, s->d1->cookie,
+ s->d1->cookie_len) != 0) {
+ al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
+ goto f_err;
+ }
+ /* Set to -2 so if successful we return 2 */
+ ret = -2;
+ }
+
+ p += cookie_len;
+ if (s->method->version == DTLS_ANY_VERSION) {
+ /* Select version to use */
+ if (s->client_version <= DTLS1_2_VERSION &&
+ !(s->options & SSL_OP_NO_DTLSv1_2)) {
+ s->version = DTLS1_2_VERSION;
+ s->method = DTLSv1_2_server_method();
+ } else if (tls1_suiteb(s)) {
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
+ SSL_R_ONLY_DTLS_1_2_ALLOWED_IN_SUITEB_MODE);
+ s->version = s->client_version;
+ al = SSL_AD_PROTOCOL_VERSION;
+ goto f_err;
+ } else if (s->client_version <= DTLS1_VERSION &&
+ !(s->options & SSL_OP_NO_DTLSv1)) {
+ s->version = DTLS1_VERSION;
+ s->method = DTLSv1_server_method();
+ } else {
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
+ SSL_R_WRONG_VERSION_NUMBER);
+ s->version = s->client_version;
+ al = SSL_AD_PROTOCOL_VERSION;
+ goto f_err;
+ }
+ s->session->ssl_version = s->version;
+ }
}
- }
- if (p + 2 > d + n) {
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
- goto f_err;
- }
- n2s(p, i);
+ if (p + 2 > d + n) {
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
+ goto f_err;
+ }
+ n2s(p, i);
- if (i == 0) {
- al = SSL_AD_ILLEGAL_PARAMETER;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_NO_CIPHERS_SPECIFIED);
- goto f_err;
- }
+ if (i == 0) {
+ al = SSL_AD_ILLEGAL_PARAMETER;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_NO_CIPHERS_SPECIFIED);
+ goto f_err;
+ }
- /* i bytes of cipher data + 1 byte for compression length later */
- if ((p + i + 1) > (d + n)) {
- /* not enough data */
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
- goto f_err;
- }
- if (ssl_bytes_to_cipher_list(s, p, i, &(ciphers)) == NULL) {
- goto err;
- }
- p += i;
+ /* i bytes of cipher data + 1 byte for compression length later */
+ if ((p + i + 1) > (d + n)) {
+ /* not enough data */
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
+ goto f_err;
+ }
+ if (ssl_bytes_to_cipher_list(s, p, i, &(ciphers), 0) == NULL) {
+ goto err;
+ }
+ p += i;
- /* If it is a hit, check that the cipher is in the list */
- if (s->hit) {
- j = 0;
- id = s->session->cipher->id;
+ /* If it is a hit, check that the cipher is in the list */
+ if (s->hit) {
+ j = 0;
+ id = s->session->cipher->id;
#ifdef CIPHER_DEBUG
- fprintf(stderr, "client sent %d ciphers\n",
- sk_SSL_CIPHER_num(ciphers));
+ fprintf(stderr, "client sent %d ciphers\n",
+ sk_SSL_CIPHER_num(ciphers));
#endif
- for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
- c = sk_SSL_CIPHER_value(ciphers, i);
+ for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
+ c = sk_SSL_CIPHER_value(ciphers, i);
#ifdef CIPHER_DEBUG
- fprintf(stderr, "client [%2d of %2d]:%s\n",
- i, sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c));
+ fprintf(stderr, "client [%2d of %2d]:%s\n",
+ i, sk_SSL_CIPHER_num(ciphers), SSL_CIPHER_get_name(c));
#endif
- if (c->id == id) {
- j = 1;
- break;
+ if (c->id == id) {
+ j = 1;
+ break;
+ }
}
- }
- /*
- * Disabled because it can be used in a ciphersuite downgrade attack:
- * CVE-2010-4180.
- */
-#if 0
- if (j == 0 && (s->options & SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG)
- && (sk_SSL_CIPHER_num(ciphers) == 1)) {
/*
- * Special case as client bug workaround: the previously used
- * cipher may not be in the current list, the client instead
- * might be trying to continue using a cipher that before wasn't
- * chosen due to server preferences. We'll have to reject the
- * connection if the cipher is not enabled, though.
+ * Disabled because it can be used in a ciphersuite downgrade
+ * attack:
+ * CVE-2010-4180.
*/
- c = sk_SSL_CIPHER_value(ciphers, 0);
- if (sk_SSL_CIPHER_find(SSL_get_ciphers(s), c) >= 0) {
- s->session->cipher = c;
- j = 1;
+#if 0
+ if (j == 0 && (s->options & SSL_OP_NETSCAPE_REUSE_CIPHER_CHANGE_BUG)
+ && (sk_SSL_CIPHER_num(ciphers) == 1)) {
+ /*
+ * Special case as client bug workaround: the previously used
+ * cipher may not be in the current list, the client instead
+ * might be trying to continue using a cipher that before wasn't
+ * chosen due to server preferences. We'll have to reject the
+ * connection if the cipher is not enabled, though.
+ */
+ c = sk_SSL_CIPHER_value(ciphers, 0);
+ if (sk_SSL_CIPHER_find(SSL_get_ciphers(s), c) >= 0) {
+ s->session->cipher = c;
+ j = 1;
+ }
}
- }
#endif
- if (j == 0) {
- /*
- * we need to have the cipher in the cipher list if we are asked
- * to reuse it
- */
- al = SSL_AD_ILLEGAL_PARAMETER;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
- SSL_R_REQUIRED_CIPHER_MISSING);
- goto f_err;
+ if (j == 0) {
+ /*
+ * we need to have the cipher in the cipher list if we are asked
+ * to reuse it
+ */
+ al = SSL_AD_ILLEGAL_PARAMETER;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
+ SSL_R_REQUIRED_CIPHER_MISSING);
+ goto f_err;
+ }
}
- }
- /* compression */
- i = *(p++);
- if ((p + i) > (d + n)) {
- /* not enough data */
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
- goto f_err;
- }
+ /* compression */
+ i = *(p++);
+ if ((p + i) > (d + n)) {
+ /* not enough data */
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
+ goto f_err;
+ }
#ifndef OPENSSL_NO_COMP
- q = p;
+ q = p;
#endif
- for (j = 0; j < i; j++) {
- if (p[j] == 0)
- break;
- }
+ for (j = 0; j < i; j++) {
+ if (p[j] == 0)
+ break;
+ }
- p += i;
- if (j >= i) {
- /* no compress */
- al = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_NO_COMPRESSION_SPECIFIED);
- goto f_err;
+ p += i;
+ if (j >= i) {
+ /* no compress */
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_NO_COMPRESSION_SPECIFIED);
+ goto f_err;
+ }
}
+
#ifndef OPENSSL_NO_TLSEXT
/* TLS extensions */
if (s->version >= SSL3_VERSION) {
projects / openssl.git / blobdiff