| /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) |
| * All rights reserved. |
| * |
| * This package is an SSL implementation written |
| * by Eric Young (eay@cryptsoft.com). |
| * The implementation was written so as to conform with Netscapes SSL. |
| * |
| * This library is free for commercial and non-commercial use as long as |
| * the following conditions are aheared to. The following conditions |
| * apply to all code found in this distribution, be it the RC4, RSA, |
| * lhash, DES, etc., code; not just the SSL code. The SSL documentation |
| * included with this distribution is covered by the same copyright terms |
| * except that the holder is Tim Hudson (tjh@cryptsoft.com). |
| * |
| * Copyright remains Eric Young's, and as such any Copyright notices in |
| * the code are not to be removed. |
| * If this package is used in a product, Eric Young should be given attribution |
| * as the author of the parts of the library used. |
| * This can be in the form of a textual message at program startup or |
| * in documentation (online or textual) provided with the package. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * "This product includes cryptographic software written by |
| * Eric Young (eay@cryptsoft.com)" |
| * The word 'cryptographic' can be left out if the rouines from the library |
| * being used are not cryptographic related :-). |
| * 4. If you include any Windows specific code (or a derivative thereof) from |
| * the apps directory (application code) you must include an acknowledgement: |
| * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
| * |
| * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * The licence and distribution terms for any publically available version or |
| * derivative of this code cannot be changed. i.e. this code cannot simply be |
| * copied and put under another distribution licence |
| * [including the GNU Public Licence.] |
| */ |
| /* ==================================================================== |
| * Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. All advertising materials mentioning features or use of this |
| * software must display the following acknowledgment: |
| * "This product includes software developed by the OpenSSL Project |
| * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" |
| * |
| * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
| * endorse or promote products derived from this software without |
| * prior written permission. For written permission, please contact |
| * openssl-core@openssl.org. |
| * |
| * 5. Products derived from this software may not be called "OpenSSL" |
| * nor may "OpenSSL" appear in their names without prior written |
| * permission of the OpenSSL Project. |
| * |
| * 6. Redistributions of any form whatsoever must retain the following |
| * acknowledgment: |
| * "This product includes software developed by the OpenSSL Project |
| * for use in the OpenSSL Toolkit (http://www.openssl.org/)" |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
| * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| * OF THE POSSIBILITY OF SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This product includes cryptographic software written by Eric Young |
| * (eay@cryptsoft.com). This product includes software written by Tim |
| * Hudson (tjh@cryptsoft.com). */ |
| |
| #include <assert.h> |
| #include <limits.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include <openssl/bytestring.h> |
| #include <openssl/err.h> |
| #include <openssl/evp.h> |
| #include <openssl/hmac.h> |
| #include <openssl/mem.h> |
| #include <openssl/obj.h> |
| #include <openssl/rand.h> |
| |
| #include "internal.h" |
| |
| |
| static int ssl_check_clienthello_tlsext(SSL *s); |
| static int ssl_check_serverhello_tlsext(SSL *s); |
| |
| const SSL3_ENC_METHOD TLSv1_enc_data = { |
| tls1_prf, |
| tls1_setup_key_block, |
| tls1_generate_master_secret, |
| tls1_change_cipher_state, |
| tls1_final_finish_mac, |
| tls1_cert_verify_mac, |
| TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE, |
| TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE, |
| tls1_alert_code, |
| tls1_export_keying_material, |
| 0, |
| }; |
| |
| const SSL3_ENC_METHOD TLSv1_1_enc_data = { |
| tls1_prf, |
| tls1_setup_key_block, |
| tls1_generate_master_secret, |
| tls1_change_cipher_state, |
| tls1_final_finish_mac, |
| tls1_cert_verify_mac, |
| TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE, |
| TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE, |
| tls1_alert_code, |
| tls1_export_keying_material, |
| SSL_ENC_FLAG_EXPLICIT_IV, |
| }; |
| |
| const SSL3_ENC_METHOD TLSv1_2_enc_data = { |
| tls1_prf, |
| tls1_setup_key_block, |
| tls1_generate_master_secret, |
| tls1_change_cipher_state, |
| tls1_final_finish_mac, |
| tls1_cert_verify_mac, |
| TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE, |
| TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE, |
| tls1_alert_code, |
| tls1_export_keying_material, |
| SSL_ENC_FLAG_EXPLICIT_IV|SSL_ENC_FLAG_SIGALGS|SSL_ENC_FLAG_SHA256_PRF |
| |SSL_ENC_FLAG_TLS1_2_CIPHERS, |
| }; |
| |
| static int compare_uint16_t(const void *p1, const void *p2) { |
| uint16_t u1 = *((const uint16_t *)p1); |
| uint16_t u2 = *((const uint16_t *)p2); |
| if (u1 < u2) { |
| return -1; |
| } else if (u1 > u2) { |
| return 1; |
| } else { |
| return 0; |
| } |
| } |
| |
| /* Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be |
| * more than one extension of the same type in a ClientHello or ServerHello. |
| * This function does an initial scan over the extensions block to filter those |
| * out. */ |
| static int tls1_check_duplicate_extensions(const CBS *cbs) { |
| CBS extensions = *cbs; |
| size_t num_extensions = 0, i = 0; |
| uint16_t *extension_types = NULL; |
| int ret = 0; |
| |
| /* First pass: count the extensions. */ |
| while (CBS_len(&extensions) > 0) { |
| uint16_t type; |
| CBS extension; |
| |
| if (!CBS_get_u16(&extensions, &type) || |
| !CBS_get_u16_length_prefixed(&extensions, &extension)) { |
| goto done; |
| } |
| |
| num_extensions++; |
| } |
| |
| if (num_extensions == 0) { |
| return 1; |
| } |
| |
| extension_types = |
| (uint16_t *)OPENSSL_malloc(sizeof(uint16_t) * num_extensions); |
| if (extension_types == NULL) { |
| OPENSSL_PUT_ERROR(SSL, tls1_check_duplicate_extensions, |
| ERR_R_MALLOC_FAILURE); |
| goto done; |
| } |
| |
| /* Second pass: gather the extension types. */ |
| extensions = *cbs; |
| for (i = 0; i < num_extensions; i++) { |
| CBS extension; |
| |
| if (!CBS_get_u16(&extensions, &extension_types[i]) || |
| !CBS_get_u16_length_prefixed(&extensions, &extension)) { |
| /* This should not happen. */ |
| goto done; |
| } |
| } |
| assert(CBS_len(&extensions) == 0); |
| |
| /* Sort the extensions and make sure there are no duplicates. */ |
| qsort(extension_types, num_extensions, sizeof(uint16_t), compare_uint16_t); |
| for (i = 1; i < num_extensions; i++) { |
| if (extension_types[i - 1] == extension_types[i]) { |
| goto done; |
| } |
| } |
| |
| ret = 1; |
| |
| done: |
| OPENSSL_free(extension_types); |
| return ret; |
| } |
| |
| char ssl_early_callback_init(struct ssl_early_callback_ctx *ctx) { |
| CBS client_hello, session_id, cipher_suites, compression_methods, extensions; |
| |
| CBS_init(&client_hello, ctx->client_hello, ctx->client_hello_len); |
| |
| if (/* Skip client version. */ |
| !CBS_skip(&client_hello, 2) || |
| /* Skip client nonce. */ |
| !CBS_skip(&client_hello, 32) || |
| /* Extract session_id. */ |
| !CBS_get_u8_length_prefixed(&client_hello, &session_id)) { |
| return 0; |
| } |
| |
| ctx->session_id = CBS_data(&session_id); |
| ctx->session_id_len = CBS_len(&session_id); |
| |
| /* Skip past DTLS cookie */ |
| if (SSL_IS_DTLS(ctx->ssl)) { |
| CBS cookie; |
| |
| if (!CBS_get_u8_length_prefixed(&client_hello, &cookie)) { |
| return 0; |
| } |
| } |
| |
| /* Extract cipher_suites. */ |
| if (!CBS_get_u16_length_prefixed(&client_hello, &cipher_suites) || |
| CBS_len(&cipher_suites) < 2 || (CBS_len(&cipher_suites) & 1) != 0) { |
| return 0; |
| } |
| ctx->cipher_suites = CBS_data(&cipher_suites); |
| ctx->cipher_suites_len = CBS_len(&cipher_suites); |
| |
| /* Extract compression_methods. */ |
| if (!CBS_get_u8_length_prefixed(&client_hello, &compression_methods) || |
| CBS_len(&compression_methods) < 1) { |
| return 0; |
| } |
| ctx->compression_methods = CBS_data(&compression_methods); |
| ctx->compression_methods_len = CBS_len(&compression_methods); |
| |
| /* If the ClientHello ends here then it's valid, but doesn't have any |
| * extensions. (E.g. SSLv3.) */ |
| if (CBS_len(&client_hello) == 0) { |
| ctx->extensions = NULL; |
| ctx->extensions_len = 0; |
| return 1; |
| } |
| |
| /* Extract extensions and check it is valid. */ |
| if (!CBS_get_u16_length_prefixed(&client_hello, &extensions) || |
| !tls1_check_duplicate_extensions(&extensions) || |
| CBS_len(&client_hello) != 0) { |
| return 0; |
| } |
| ctx->extensions = CBS_data(&extensions); |
| ctx->extensions_len = CBS_len(&extensions); |
| |
| return 1; |
| } |
| |
| char SSL_early_callback_ctx_extension_get( |
| const struct ssl_early_callback_ctx *ctx, uint16_t extension_type, |
| const uint8_t **out_data, size_t *out_len) { |
| CBS extensions; |
| |
| CBS_init(&extensions, ctx->extensions, ctx->extensions_len); |
| |
| while (CBS_len(&extensions) != 0) { |
| uint16_t type; |
| CBS extension; |
| |
| /* Decode the next extension. */ |
| if (!CBS_get_u16(&extensions, &type) || |
| !CBS_get_u16_length_prefixed(&extensions, &extension)) { |
| return 0; |
| } |
| |
| if (type == extension_type) { |
| *out_data = CBS_data(&extension); |
| *out_len = CBS_len(&extension); |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| struct tls_curve { |
| uint16_t curve_id; |
| int nid; |
| }; |
| |
| /* ECC curves from RFC4492. */ |
| static const struct tls_curve tls_curves[] = { |
| {21, NID_secp224r1}, |
| {23, NID_X9_62_prime256v1}, |
| {24, NID_secp384r1}, |
| {25, NID_secp521r1}, |
| }; |
| |
| static const uint8_t ecformats_default[] = { |
| TLSEXT_ECPOINTFORMAT_uncompressed, |
| }; |
| |
| static const uint16_t eccurves_default[] = { |
| 23, /* X9_62_prime256v1 */ |
| 24, /* secp384r1 */ |
| }; |
| |
| int tls1_ec_curve_id2nid(uint16_t curve_id) { |
| size_t i; |
| for (i = 0; i < sizeof(tls_curves) / sizeof(tls_curves[0]); i++) { |
| if (curve_id == tls_curves[i].curve_id) { |
| return tls_curves[i].nid; |
| } |
| } |
| return NID_undef; |
| } |
| |
| int tls1_ec_nid2curve_id(uint16_t *out_curve_id, int nid) { |
| size_t i; |
| for (i = 0; i < sizeof(tls_curves) / sizeof(tls_curves[0]); i++) { |
| if (nid == tls_curves[i].nid) { |
| *out_curve_id = tls_curves[i].curve_id; |
| return 1; |
| } |
| } |
| return 0; |
| } |
| |
| /* tls1_get_curvelist sets |*out_curve_ids| and |*out_curve_ids_len| to the |
| * list of allowed curve IDs. If |get_peer_curves| is non-zero, return the |
| * peer's curve list. Otherwise, return the preferred list. */ |
| static void tls1_get_curvelist(SSL *s, int get_peer_curves, |
| const uint16_t **out_curve_ids, |
| size_t *out_curve_ids_len) { |
| if (get_peer_curves) { |
| /* Only clients send a curve list, so this function is only called |
| * on the server. */ |
| assert(s->server); |
| *out_curve_ids = s->s3->tmp.peer_ellipticcurvelist; |
| *out_curve_ids_len = s->s3->tmp.peer_ellipticcurvelist_length; |
| return; |
| } |
| |
| *out_curve_ids = s->tlsext_ellipticcurvelist; |
| *out_curve_ids_len = s->tlsext_ellipticcurvelist_length; |
| if (!*out_curve_ids) { |
| *out_curve_ids = eccurves_default; |
| *out_curve_ids_len = sizeof(eccurves_default) / sizeof(eccurves_default[0]); |
| } |
| } |
| |
| int tls1_check_curve(SSL *s, CBS *cbs, uint16_t *out_curve_id) { |
| uint8_t curve_type; |
| uint16_t curve_id; |
| const uint16_t *curves; |
| size_t curves_len, i; |
| |
| /* Only support named curves. */ |
| if (!CBS_get_u8(cbs, &curve_type) || |
| curve_type != NAMED_CURVE_TYPE || |
| !CBS_get_u16(cbs, &curve_id)) { |
| return 0; |
| } |
| |
| tls1_get_curvelist(s, 0, &curves, &curves_len); |
| for (i = 0; i < curves_len; i++) { |
| if (curve_id == curves[i]) { |
| *out_curve_id = curve_id; |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| int tls1_get_shared_curve(SSL *s) { |
| const uint16_t *curves, *peer_curves, *pref, *supp; |
| size_t curves_len, peer_curves_len, pref_len, supp_len, i, j; |
| |
| /* Can't do anything on client side */ |
| if (s->server == 0) { |
| return NID_undef; |
| } |
| |
| tls1_get_curvelist(s, 0 /* local curves */, &curves, &curves_len); |
| tls1_get_curvelist(s, 1 /* peer curves */, &peer_curves, &peer_curves_len); |
| |
| if (peer_curves_len == 0) { |
| /* Clients are not required to send a supported_curves extension. In this |
| * case, the server is free to pick any curve it likes. See RFC 4492, |
| * section 4, paragraph 3. */ |
| return (curves_len == 0) ? NID_undef : tls1_ec_curve_id2nid(curves[0]); |
| } |
| |
| if (s->options & SSL_OP_CIPHER_SERVER_PREFERENCE) { |
| pref = curves; |
| pref_len = curves_len; |
| supp = peer_curves; |
| supp_len = peer_curves_len; |
| } else { |
| pref = peer_curves; |
| pref_len = peer_curves_len; |
| supp = curves; |
| supp_len = curves_len; |
| } |
| |
| for (i = 0; i < pref_len; i++) { |
| for (j = 0; j < supp_len; j++) { |
| if (pref[i] == supp[j]) { |
| return tls1_ec_curve_id2nid(pref[i]); |
| } |
| } |
| } |
| |
| return NID_undef; |
| } |
| |
| int tls1_set_curves(uint16_t **out_curve_ids, size_t *out_curve_ids_len, |
| const int *curves, size_t ncurves) { |
| uint16_t *curve_ids; |
| size_t i; |
| |
| curve_ids = (uint16_t *)OPENSSL_malloc(ncurves * sizeof(uint16_t)); |
| if (curve_ids == NULL) { |
| return 0; |
| } |
| |
| for (i = 0; i < ncurves; i++) { |
| if (!tls1_ec_nid2curve_id(&curve_ids[i], curves[i])) { |
| OPENSSL_free(curve_ids); |
| return 0; |
| } |
| } |
| |
| OPENSSL_free(*out_curve_ids); |
| *out_curve_ids = curve_ids; |
| *out_curve_ids_len = ncurves; |
| |
| return 1; |
| } |
| |
| /* tls1_curve_params_from_ec_key sets |*out_curve_id| and |*out_comp_id| to the |
| * TLS curve ID and point format, respectively, for |ec|. It returns one on |
| * success and zero on failure. */ |
| static int tls1_curve_params_from_ec_key(uint16_t *out_curve_id, |
| uint8_t *out_comp_id, EC_KEY *ec) { |
| int nid; |
| uint16_t id; |
| const EC_GROUP *grp; |
| |
| if (ec == NULL) { |
| return 0; |
| } |
| |
| grp = EC_KEY_get0_group(ec); |
| if (grp == NULL) { |
| return 0; |
| } |
| |
| /* Determine curve ID */ |
| nid = EC_GROUP_get_curve_name(grp); |
| if (!tls1_ec_nid2curve_id(&id, nid)) { |
| return 0; |
| } |
| |
| /* Set the named curve ID. Arbitrary explicit curves are not supported. */ |
| *out_curve_id = id; |
| |
| if (out_comp_id) { |
| if (EC_KEY_get0_public_key(ec) == NULL) { |
| return 0; |
| } |
| if (EC_KEY_get_conv_form(ec) == POINT_CONVERSION_COMPRESSED) { |
| *out_comp_id = TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime; |
| } else { |
| *out_comp_id = TLSEXT_ECPOINTFORMAT_uncompressed; |
| } |
| } |
| |
| return 1; |
| } |
| |
| /* tls1_check_point_format returns one if |comp_id| is consistent with the |
| * peer's point format preferences. */ |
| static int tls1_check_point_format(SSL *s, uint8_t comp_id) { |
| uint8_t *p = s->s3->tmp.peer_ecpointformatlist; |
| size_t plen = s->s3->tmp.peer_ecpointformatlist_length; |
| size_t i; |
| |
| /* If point formats extension present check it, otherwise everything is |
| * supported (see RFC4492). */ |
| if (p == NULL) { |
| return 1; |
| } |
| |
| for (i = 0; i < plen; i++) { |
| if (comp_id == p[i]) { |
| return 1; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* tls1_check_curve_id returns one if |curve_id| is consistent with both our |
| * and the peer's curve preferences. Note: if called as the client, only our |
| * preferences are checked; the peer (the server) does not send preferences. */ |
| static int tls1_check_curve_id(SSL *s, uint16_t curve_id) { |
| const uint16_t *curves; |
| size_t curves_len, i, get_peer_curves; |
| |
| /* Check against our list, then the peer's list. */ |
| for (get_peer_curves = 0; get_peer_curves <= 1; get_peer_curves++) { |
| if (get_peer_curves && !s->server) { |
| /* Servers do not present a preference list so, if we are a client, only |
| * check our list. */ |
| continue; |
| } |
| |
| tls1_get_curvelist(s, get_peer_curves, &curves, &curves_len); |
| if (get_peer_curves && curves_len == 0) { |
| /* Clients are not required to send a supported_curves extension. In this |
| * case, the server is free to pick any curve it likes. See RFC 4492, |
| * section 4, paragraph 3. */ |
| continue; |
| } |
| for (i = 0; i < curves_len; i++) { |
| if (curves[i] == curve_id) { |
| break; |
| } |
| } |
| |
| if (i == curves_len) { |
| return 0; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static void tls1_get_formatlist(SSL *s, const uint8_t **pformats, |
| size_t *pformatslen) { |
| /* If we have a custom point format list use it otherwise use default */ |
| if (s->tlsext_ecpointformatlist) { |
| *pformats = s->tlsext_ecpointformatlist; |
| *pformatslen = s->tlsext_ecpointformatlist_length; |
| } else { |
| *pformats = ecformats_default; |
| *pformatslen = sizeof(ecformats_default); |
| } |
| } |
| |
| int tls1_check_ec_cert(SSL *s, X509 *x) { |
| int ret = 0; |
| EVP_PKEY *pkey = X509_get_pubkey(x); |
| uint16_t curve_id; |
| uint8_t comp_id; |
| |
| if (!pkey || |
| pkey->type != EVP_PKEY_EC || |
| !tls1_curve_params_from_ec_key(&curve_id, &comp_id, pkey->pkey.ec) || |
| !tls1_check_curve_id(s, curve_id) || |
| !tls1_check_point_format(s, comp_id)) { |
| goto done; |
| } |
| |
| ret = 1; |
| |
| done: |
| EVP_PKEY_free(pkey); |
| return ret; |
| } |
| |
| int tls1_check_ec_tmp_key(SSL *s) { |
| if (s->cert->ecdh_nid != NID_undef) { |
| /* If the curve is preconfigured, ECDH is acceptable iff the peer supports |
| * the curve. */ |
| uint16_t curve_id; |
| return tls1_ec_nid2curve_id(&curve_id, s->cert->ecdh_nid) && |
| tls1_check_curve_id(s, curve_id); |
| } |
| |
| if (s->cert->ecdh_tmp_cb != NULL) { |
| /* Assume the callback will provide an acceptable curve. */ |
| return 1; |
| } |
| |
| /* Otherwise, the curve gets selected automatically. ECDH is acceptable iff |
| * there is a shared curve. */ |
| return tls1_get_shared_curve(s) != NID_undef; |
| } |
| |
| /* List of supported signature algorithms and hashes. Should make this |
| * customisable at some point, for now include everything we support. */ |
| |
| #define tlsext_sigalg_rsa(md) md, TLSEXT_signature_rsa, |
| |
| #define tlsext_sigalg_ecdsa(md) md, TLSEXT_signature_ecdsa, |
| |
| #define tlsext_sigalg(md) tlsext_sigalg_rsa(md) tlsext_sigalg_ecdsa(md) |
| |
| static const uint8_t tls12_sigalgs[] = { |
| tlsext_sigalg(TLSEXT_hash_sha512) |
| tlsext_sigalg(TLSEXT_hash_sha384) |
| tlsext_sigalg(TLSEXT_hash_sha256) |
| tlsext_sigalg(TLSEXT_hash_sha224) |
| tlsext_sigalg(TLSEXT_hash_sha1) |
| }; |
| |
| size_t tls12_get_psigalgs(SSL *s, const uint8_t **psigs) { |
| /* If server use client authentication sigalgs if not NULL */ |
| if (s->server && s->cert->client_sigalgs) { |
| *psigs = s->cert->client_sigalgs; |
| return s->cert->client_sigalgslen; |
| } else if (s->cert->conf_sigalgs) { |
| *psigs = s->cert->conf_sigalgs; |
| return s->cert->conf_sigalgslen; |
| } else { |
| *psigs = tls12_sigalgs; |
| return sizeof(tls12_sigalgs); |
| } |
| } |
| |
| /* tls12_check_peer_sigalg parses a SignatureAndHashAlgorithm out of |cbs|. It |
| * checks it is consistent with |s|'s sent supported signature algorithms and, |
| * if so, writes the relevant digest into |*out_md| and returns 1. Otherwise it |
| * returns 0 and writes an alert into |*out_alert|. */ |
| int tls12_check_peer_sigalg(const EVP_MD **out_md, int *out_alert, SSL *s, |
| CBS *cbs, EVP_PKEY *pkey) { |
| const uint8_t *sent_sigs; |
| size_t sent_sigslen, i; |
| int sigalg = tls12_get_sigid(pkey->type); |
| uint8_t hash, signature; |
| |
| /* Should never happen */ |
| if (sigalg == -1) { |
| OPENSSL_PUT_ERROR(SSL, tls12_check_peer_sigalg, ERR_R_INTERNAL_ERROR); |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| if (!CBS_get_u8(cbs, &hash) || |
| !CBS_get_u8(cbs, &signature)) { |
| OPENSSL_PUT_ERROR(SSL, tls12_check_peer_sigalg, SSL_R_DECODE_ERROR); |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| /* Check key type is consistent with signature */ |
| if (sigalg != signature) { |
| OPENSSL_PUT_ERROR(SSL, tls12_check_peer_sigalg, SSL_R_WRONG_SIGNATURE_TYPE); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| |
| if (pkey->type == EVP_PKEY_EC) { |
| uint16_t curve_id; |
| uint8_t comp_id; |
| /* Check compression and curve matches extensions */ |
| if (!tls1_curve_params_from_ec_key(&curve_id, &comp_id, pkey->pkey.ec)) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| if (s->server && (!tls1_check_curve_id(s, curve_id) || |
| !tls1_check_point_format(s, comp_id))) { |
| OPENSSL_PUT_ERROR(SSL, tls12_check_peer_sigalg, SSL_R_WRONG_CURVE); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| } |
| |
| /* Check signature matches a type we sent */ |
| sent_sigslen = tls12_get_psigalgs(s, &sent_sigs); |
| for (i = 0; i < sent_sigslen; i += 2, sent_sigs += 2) { |
| if (hash == sent_sigs[0] && signature == sent_sigs[1]) { |
| break; |
| } |
| } |
| |
| /* Allow fallback to SHA-1. */ |
| if (i == sent_sigslen && hash != TLSEXT_hash_sha1) { |
| OPENSSL_PUT_ERROR(SSL, tls12_check_peer_sigalg, SSL_R_WRONG_SIGNATURE_TYPE); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| |
| *out_md = tls12_get_hash(hash); |
| if (*out_md == NULL) { |
| OPENSSL_PUT_ERROR(SSL, tls12_check_peer_sigalg, SSL_R_UNKNOWN_DIGEST); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* Get a mask of disabled algorithms: an algorithm is disabled if it isn't |
| * supported or doesn't appear in supported signature algorithms. Unlike |
| * ssl_cipher_get_disabled this applies to a specific session and not global |
| * settings. */ |
| void ssl_set_client_disabled(SSL *s) { |
| CERT *c = s->cert; |
| const uint8_t *sigalgs; |
| size_t i, sigalgslen; |
| int have_rsa = 0, have_ecdsa = 0; |
| c->mask_a = 0; |
| c->mask_k = 0; |
| |
| /* Don't allow TLS 1.2 only ciphers if we don't suppport them */ |
| if (!SSL_CLIENT_USE_TLS1_2_CIPHERS(s)) { |
| c->mask_ssl = SSL_TLSV1_2; |
| } else { |
| c->mask_ssl = 0; |
| } |
| |
| /* Now go through all signature algorithms seeing if we support any for RSA, |
| * DSA, ECDSA. Do this for all versions not just TLS 1.2. */ |
| sigalgslen = tls12_get_psigalgs(s, &sigalgs); |
| for (i = 0; i < sigalgslen; i += 2, sigalgs += 2) { |
| switch (sigalgs[1]) { |
| case TLSEXT_signature_rsa: |
| have_rsa = 1; |
| break; |
| |
| case TLSEXT_signature_ecdsa: |
| have_ecdsa = 1; |
| break; |
| } |
| } |
| |
| /* Disable auth if we don't include any appropriate signature algorithms. */ |
| if (!have_rsa) { |
| c->mask_a |= SSL_aRSA; |
| } |
| if (!have_ecdsa) { |
| c->mask_a |= SSL_aECDSA; |
| } |
| |
| /* with PSK there must be client callback set */ |
| if (!s->psk_client_callback) { |
| c->mask_a |= SSL_aPSK; |
| c->mask_k |= SSL_kPSK; |
| } |
| } |
| |
| /* tls_extension represents a TLS extension that is handled internally. The |
| * |init| function is called for each handshake, before any other functions of |
| * the extension. Then the add and parse callbacks are called as needed. |
| * |
| * The parse callbacks receive a |CBS| that contains the contents of the |
| * extension (i.e. not including the type and length bytes). If an extension is |
| * not received then the parse callbacks will be called with a NULL CBS so that |
| * they can do any processing needed to handle the absence of an extension. |
| * |
| * The add callbacks receive a |CBB| to which the extension can be appended but |
| * the function is responsible for appending the type and length bytes too. |
| * |
| * All callbacks return one for success and zero for error. If a parse function |
| * returns zero then a fatal alert with value |*out_alert| will be sent. If |
| * |*out_alert| isn't set, then a |decode_error| alert will be sent. */ |
| struct tls_extension { |
| uint16_t value; |
| void (*init)(SSL *ssl); |
| |
| int (*add_clienthello)(SSL *ssl, CBB *out); |
| int (*parse_serverhello)(SSL *ssl, uint8_t *out_alert, CBS *contents); |
| |
| int (*parse_clienthello)(SSL *ssl, uint8_t *out_alert, CBS *contents); |
| int (*add_serverhello)(SSL *ssl, CBB *out); |
| }; |
| |
| |
| /* Server name indication (SNI). |
| * |
| * https://tools.ietf.org/html/rfc6066#section-3. */ |
| |
| static void ext_sni_init(SSL *ssl) { |
| ssl->s3->tmp.should_ack_sni = 0; |
| } |
| |
| static int ext_sni_add_clienthello(SSL *ssl, CBB *out) { |
| if (ssl->tlsext_hostname == NULL) { |
| return 1; |
| } |
| |
| CBB contents, server_name_list, name; |
| if (!CBB_add_u16(out, TLSEXT_TYPE_server_name) || |
| !CBB_add_u16_length_prefixed(out, &contents) || |
| !CBB_add_u16_length_prefixed(&contents, &server_name_list) || |
| !CBB_add_u8(&server_name_list, TLSEXT_NAMETYPE_host_name) || |
| !CBB_add_u16_length_prefixed(&server_name_list, &name) || |
| !CBB_add_bytes(&name, (const uint8_t *)ssl->tlsext_hostname, |
| strlen(ssl->tlsext_hostname)) || |
| !CBB_flush(out)) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| static int ext_sni_parse_serverhello(SSL *ssl, uint8_t *out_alert, CBS *contents) { |
| if (contents == NULL) { |
| return 1; |
| } |
| |
| if (CBS_len(contents) != 0) { |
| return 0; |
| } |
| |
| assert(ssl->tlsext_hostname != NULL); |
| |
| if (!ssl->hit) { |
| assert(ssl->session->tlsext_hostname == NULL); |
| ssl->session->tlsext_hostname = BUF_strdup(ssl->tlsext_hostname); |
| if (!ssl->session->tlsext_hostname) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int ext_sni_parse_clienthello(SSL *ssl, uint8_t *out_alert, CBS *contents) { |
| if (contents == NULL) { |
| return 1; |
| } |
| |
| /* The servername extension is treated as follows: |
| * |
| * - Only the hostname type is supported with a maximum length of 255. |
| * - The servername is rejected if too long or if it contains zeros, in |
| * which case an fatal alert is generated. |
| * - The servername field is maintained together with the session cache. |
| * - When a session is resumed, the servername callback is invoked in order |
| * to allow the application to position itself to the right context. |
| * - The servername is acknowledged if it is new for a session or when |
| * it is identical to a previously used for the same session. |
| * Applications can control the behaviour. They can at any time |
| * set a 'desirable' servername for a new SSL object. This can be the |
| * case for example with HTTPS when a Host: header field is received and |
| * a renegotiation is requested. In this case, a possible servername |
| * presented in the new client hello is only acknowledged if it matches |
| * the value of the Host: field. |
| * - Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION |
| * if they provide for changing an explicit servername context for the |
| * session, |
| * i.e. when the session has been established with a servername extension. |
| */ |
| |
| CBS server_name_list; |
| char have_seen_host_name = 0; |
| |
| if (!CBS_get_u16_length_prefixed(contents, &server_name_list) || |
| CBS_len(&server_name_list) == 0 || |
| CBS_len(contents) != 0) { |
| return 0; |
| } |
| |
| /* Decode each ServerName in the extension. */ |
| while (CBS_len(&server_name_list) > 0) { |
| uint8_t name_type; |
| CBS host_name; |
| |
| if (!CBS_get_u8(&server_name_list, &name_type) || |
| !CBS_get_u16_length_prefixed(&server_name_list, &host_name)) { |
| return 0; |
| } |
| |
| /* Only host_name is supported. */ |
| if (name_type != TLSEXT_NAMETYPE_host_name) { |
| continue; |
| } |
| |
| if (have_seen_host_name) { |
| /* The ServerNameList MUST NOT contain more than one name of the same |
| * name_type. */ |
| return 0; |
| } |
| |
| have_seen_host_name = 1; |
| |
| if (CBS_len(&host_name) == 0 || |
| CBS_len(&host_name) > TLSEXT_MAXLEN_host_name || |
| CBS_contains_zero_byte(&host_name)) { |
| *out_alert = SSL_AD_UNRECOGNIZED_NAME; |
| return 0; |
| } |
| |
| if (!ssl->hit) { |
| assert(ssl->session->tlsext_hostname == NULL); |
| if (ssl->session->tlsext_hostname) { |
| /* This should be impossible. */ |
| return 0; |
| } |
| |
| /* Copy the hostname as a string. */ |
| if (!CBS_strdup(&host_name, &ssl->session->tlsext_hostname)) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| ssl->s3->tmp.should_ack_sni = 1; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int ext_sni_add_serverhello(SSL *ssl, CBB *out) { |
| if (ssl->hit || |
| !ssl->s3->tmp.should_ack_sni || |
| ssl->session->tlsext_hostname == NULL) { |
| return 1; |
| } |
| |
| if (!CBB_add_u16(out, TLSEXT_TYPE_server_name) || |
| !CBB_add_u16(out, 0 /* length */)) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| |
| /* Renegotiation indication. |
| * |
| * https://tools.ietf.org/html/rfc5746 */ |
| |
| static int ext_ri_add_clienthello(SSL *ssl, CBB *out) { |
| CBB contents, prev_finished; |
| if (!CBB_add_u16(out, TLSEXT_TYPE_renegotiate) || |
| !CBB_add_u16_length_prefixed(out, &contents) || |
| !CBB_add_u8_length_prefixed(&contents, &prev_finished) || |
| !CBB_add_bytes(&prev_finished, ssl->s3->previous_client_finished, |
| ssl->s3->previous_client_finished_len) || |
| !CBB_flush(out)) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| static int ext_ri_parse_serverhello(SSL *ssl, uint8_t *out_alert, |
| CBS *contents) { |
| if (contents == NULL) { |
| /* No renegotiation extension received. |
| * |
| * Strictly speaking if we want to avoid an attack we should *always* see |
| * RI even on initial ServerHello because the client doesn't see any |
| * renegotiation during an attack. However this would mean we could not |
| * connect to any server which doesn't support RI. |
| * |
| * A lack of the extension is allowed if SSL_OP_LEGACY_SERVER_CONNECT is |
| * defined. */ |
| if (ssl->options & SSL_OP_LEGACY_SERVER_CONNECT) { |
| return 1; |
| } |
| |
| *out_alert = SSL_AD_HANDSHAKE_FAILURE; |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_serverhello, |
| SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); |
| return 0; |
| } |
| |
| const size_t expected_len = ssl->s3->previous_client_finished_len + |
| ssl->s3->previous_server_finished_len; |
| |
| /* Check for logic errors */ |
| assert(!expected_len || ssl->s3->previous_client_finished_len); |
| assert(!expected_len || ssl->s3->previous_server_finished_len); |
| |
| /* Parse out the extension contents. */ |
| CBS renegotiated_connection; |
| if (!CBS_get_u8_length_prefixed(contents, &renegotiated_connection) || |
| CBS_len(contents) != 0) { |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_serverhello, |
| SSL_R_RENEGOTIATION_ENCODING_ERR); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| |
| /* Check that the extension matches. */ |
| if (CBS_len(&renegotiated_connection) != expected_len) { |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_serverhello, |
| SSL_R_RENEGOTIATION_MISMATCH); |
| *out_alert = SSL_AD_HANDSHAKE_FAILURE; |
| return 0; |
| } |
| |
| const uint8_t *d = CBS_data(&renegotiated_connection); |
| if (CRYPTO_memcmp(d, ssl->s3->previous_client_finished, |
| ssl->s3->previous_client_finished_len)) { |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_serverhello, |
| SSL_R_RENEGOTIATION_MISMATCH); |
| *out_alert = SSL_AD_HANDSHAKE_FAILURE; |
| return 0; |
| } |
| d += ssl->s3->previous_client_finished_len; |
| |
| if (CRYPTO_memcmp(d, ssl->s3->previous_server_finished, |
| ssl->s3->previous_server_finished_len)) { |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_serverhello, |
| SSL_R_RENEGOTIATION_MISMATCH); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| ssl->s3->send_connection_binding = 1; |
| |
| return 1; |
| } |
| |
| static int ext_ri_parse_clienthello(SSL *ssl, uint8_t *out_alert, |
| CBS *contents) { |
| /* Renegotiation isn't supported as a server so this function should never be |
| * called after the initial handshake. */ |
| assert(!ssl->s3->initial_handshake_complete); |
| |
| CBS fake_contents; |
| static const uint8_t kFakeExtension[] = {0}; |
| |
| if (contents == NULL) { |
| if (ssl->s3->send_connection_binding) { |
| /* The renegotiation SCSV was received so pretend that we received a |
| * renegotiation extension. */ |
| CBS_init(&fake_contents, kFakeExtension, sizeof(kFakeExtension)); |
| contents = &fake_contents; |
| /* We require that the renegotiation extension is at index zero of |
| * kExtensions. */ |
| ssl->s3->tmp.extensions.received |= (1u << 0); |
| } else { |
| return 1; |
| } |
| } |
| |
| CBS renegotiated_connection; |
| |
| if (!CBS_get_u8_length_prefixed(contents, &renegotiated_connection) || |
| CBS_len(contents) != 0) { |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_clienthello, |
| SSL_R_RENEGOTIATION_ENCODING_ERR); |
| return 0; |
| } |
| |
| /* Check that the extension matches */ |
| if (!CBS_mem_equal(&renegotiated_connection, ssl->s3->previous_client_finished, |
| ssl->s3->previous_client_finished_len)) { |
| OPENSSL_PUT_ERROR(SSL, ext_ri_parse_clienthello, |
| SSL_R_RENEGOTIATION_MISMATCH); |
| *out_alert = SSL_AD_HANDSHAKE_FAILURE; |
| return 0; |
| } |
| |
| ssl->s3->send_connection_binding = 1; |
| |
| return 1; |
| } |
| |
| static int ext_ri_add_serverhello(SSL *ssl, CBB *out) { |
| CBB contents, prev_finished; |
| if (!CBB_add_u16(out, TLSEXT_TYPE_renegotiate) || |
| !CBB_add_u16_length_prefixed(out, &contents) || |
| !CBB_add_u8_length_prefixed(&contents, &prev_finished) || |
| !CBB_add_bytes(&prev_finished, ssl->s3->previous_client_finished, |
| ssl->s3->previous_client_finished_len) || |
| !CBB_add_bytes(&prev_finished, ssl->s3->previous_server_finished, |
| ssl->s3->previous_server_finished_len) || |
| !CBB_flush(out)) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* kExtensions contains all the supported extensions. */ |
| static const struct tls_extension kExtensions[] = { |
| { |
| /* The renegotiation extension must always be at index zero because the |
| * |received| and |sent| bitsets need to be tweaked when the "extension" is |
| * sent as an SCSV. */ |
| TLSEXT_TYPE_renegotiate, |
| NULL, |
| ext_ri_add_clienthello, |
| ext_ri_parse_serverhello, |
| ext_ri_parse_clienthello, |
| ext_ri_add_serverhello, |
| }, |
| { |
| TLSEXT_TYPE_server_name, |
| ext_sni_init, |
| ext_sni_add_clienthello, |
| ext_sni_parse_serverhello, |
| ext_sni_parse_clienthello, |
| ext_sni_add_serverhello, |
| }, |
| }; |
| |
| #define kNumExtensions (sizeof(kExtensions) / sizeof(struct tls_extension)) |
| |
| OPENSSL_COMPILE_ASSERT(kNumExtensions <= |
| sizeof(((SSL *)NULL)->s3->tmp.extensions.sent) * 8, |
| too_many_extensions_for_bitset); |
| OPENSSL_COMPILE_ASSERT(kNumExtensions <= |
| sizeof(((SSL *)NULL)->s3->tmp.extensions.received) * |
| 8, |
| too_many_extensions_for_bitset); |
| |
| static const struct tls_extension *tls_extension_find(uint32_t *out_index, |
| uint16_t value) { |
| unsigned i; |
| for (i = 0; i < kNumExtensions; i++) { |
| if (kExtensions[i].value == value) { |
| *out_index = i; |
| return &kExtensions[i]; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /* header_len is the length of the ClientHello header written so far, used to |
| * compute padding. It does not include the record header. Pass 0 if no padding |
| * is to be done. */ |
| uint8_t *ssl_add_clienthello_tlsext(SSL *s, uint8_t *const buf, |
| uint8_t *const limit, size_t header_len) { |
| int extdatalen = 0; |
| uint8_t *ret = buf; |
| uint8_t *orig = buf; |
| /* See if we support any ECC ciphersuites */ |
| int using_ecc = 0; |
| |
| if (s->version >= TLS1_VERSION || SSL_IS_DTLS(s)) { |
| size_t i; |
| uint32_t alg_k, alg_a; |
| STACK_OF(SSL_CIPHER) *cipher_stack = SSL_get_ciphers(s); |
| |
| for (i = 0; i < sk_SSL_CIPHER_num(cipher_stack); i++) { |
| const SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i); |
| |
| alg_k = c->algorithm_mkey; |
| alg_a = c->algorithm_auth; |
| if ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA)) { |
| using_ecc = 1; |
| break; |
| } |
| } |
| } |
| |
| /* don't add extensions for SSLv3 unless doing secure renegotiation */ |
| if (s->client_version == SSL3_VERSION && !s->s3->send_connection_binding) { |
| return orig; |
| } |
| |
| ret += 2; |
| |
| if (ret >= limit) { |
| return NULL; /* should never occur. */ |
| } |
| |
| s->s3->tmp.extensions.sent = 0; |
| |
| size_t i; |
| for (i = 0; i < kNumExtensions; i++) { |
| if (kExtensions[i].init != NULL) { |
| kExtensions[i].init(s); |
| } |
| } |
| |
| CBB cbb; |
| if (!CBB_init_fixed(&cbb, ret, limit - ret)) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| |
| for (i = 0; i < kNumExtensions; i++) { |
| const size_t len_before = CBB_len(&cbb); |
| if (!kExtensions[i].add_clienthello(s, &cbb)) { |
| CBB_cleanup(&cbb); |
| OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| const size_t len_after = CBB_len(&cbb); |
| |
| if (len_after != len_before) { |
| s->s3->tmp.extensions.sent |= (1u << i); |
| } |
| } |
| |
| ret += CBB_len(&cbb); |
| CBB_cleanup(&cbb); |
| |
| /* Add extended master secret. */ |
| if (s->version != SSL3_VERSION) { |
| if (limit - ret - 4 < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_extended_master_secret, ret); |
| s2n(0, ret); |
| } |
| |
| if (!(SSL_get_options(s) & SSL_OP_NO_TICKET)) { |
| int ticklen = 0; |
| /* Renegotiation does not participate in session resumption. However, still |
| * advertise the extension to avoid potentially breaking servers which carry |
| * over the state from the previous handshake, such as OpenSSL servers |
| * without upstream's 3c3f0259238594d77264a78944d409f2127642c4. */ |
| if (!s->s3->initial_handshake_complete && s->session != NULL && |
| s->session->tlsext_tick != NULL) { |
| ticklen = s->session->tlsext_ticklen; |
| } |
| |
| /* Check for enough room 2 for extension type, 2 for len rest for |
| * ticket. */ |
| if ((long)(limit - ret - 4 - ticklen) < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_session_ticket, ret); |
| s2n(ticklen, ret); |
| if (ticklen) { |
| memcpy(ret, s->session->tlsext_tick, ticklen); |
| ret += ticklen; |
| } |
| } |
| |
| if (ssl3_version_from_wire(s, s->client_version) >= TLS1_2_VERSION) { |
| size_t salglen; |
| const uint8_t *salg; |
| salglen = tls12_get_psigalgs(s, &salg); |
| if ((size_t)(limit - ret) < salglen + 6) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_signature_algorithms, ret); |
| s2n(salglen + 2, ret); |
| s2n(salglen, ret); |
| memcpy(ret, salg, salglen); |
| ret += salglen; |
| } |
| |
| if (s->ocsp_stapling_enabled) { |
| /* The status_request extension is excessively extensible at every layer. |
| * On the client, only support requesting OCSP responses with an empty |
| * responder_id_list and no extensions. */ |
| if (limit - ret - 4 - 1 - 2 - 2 < 0) { |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_status_request, ret); |
| s2n(1 + 2 + 2, ret); |
| /* status_type */ |
| *(ret++) = TLSEXT_STATUSTYPE_ocsp; |
| /* responder_id_list - empty */ |
| s2n(0, ret); |
| /* request_extensions - empty */ |
| s2n(0, ret); |
| } |
| |
| if (s->ctx->next_proto_select_cb && !s->s3->initial_handshake_complete && |
| !SSL_IS_DTLS(s)) { |
| /* The client advertises an emtpy extension to indicate its support for |
| * Next Protocol Negotiation */ |
| if (limit - ret - 4 < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_next_proto_neg, ret); |
| s2n(0, ret); |
| } |
| |
| if (s->signed_cert_timestamps_enabled) { |
| /* The client advertises an empty extension to indicate its support for |
| * certificate timestamps. */ |
| if (limit - ret - 4 < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_certificate_timestamp, ret); |
| s2n(0, ret); |
| } |
| |
| if (s->alpn_client_proto_list && !s->s3->initial_handshake_complete) { |
| if ((size_t)(limit - ret) < 6 + s->alpn_client_proto_list_len) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_application_layer_protocol_negotiation, ret); |
| s2n(2 + s->alpn_client_proto_list_len, ret); |
| s2n(s->alpn_client_proto_list_len, ret); |
| memcpy(ret, s->alpn_client_proto_list, s->alpn_client_proto_list_len); |
| ret += s->alpn_client_proto_list_len; |
| } |
| |
| if (s->tlsext_channel_id_enabled && !SSL_IS_DTLS(s)) { |
| /* The client advertises an emtpy extension to indicate its support for |
| * Channel ID. */ |
| if (limit - ret - 4 < 0) { |
| return NULL; |
| } |
| if (s->ctx->tlsext_channel_id_enabled_new) { |
| s2n(TLSEXT_TYPE_channel_id_new, ret); |
| } else { |
| s2n(TLSEXT_TYPE_channel_id, ret); |
| } |
| s2n(0, ret); |
| } |
| |
| if (SSL_get_srtp_profiles(s)) { |
| int el; |
| |
| ssl_add_clienthello_use_srtp_ext(s, 0, &el, 0); |
| |
| if ((limit - ret - 4 - el) < 0) { |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_use_srtp, ret); |
| s2n(el, ret); |
| |
| if (!ssl_add_clienthello_use_srtp_ext(s, ret, &el, el)) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| ret += el; |
| } |
| |
| if (using_ecc) { |
| /* Add TLS extension ECPointFormats to the ClientHello message */ |
| long lenmax; |
| const uint8_t *formats; |
| const uint16_t *curves; |
| size_t formats_len, curves_len; |
| |
| tls1_get_formatlist(s, &formats, &formats_len); |
| |
| lenmax = limit - ret - 5; |
| if (lenmax < 0) { |
| return NULL; |
| } |
| if (formats_len > (size_t)lenmax) { |
| return NULL; |
| } |
| if (formats_len > 255) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_ec_point_formats, ret); |
| s2n(formats_len + 1, ret); |
| *(ret++) = (uint8_t)formats_len; |
| memcpy(ret, formats, formats_len); |
| ret += formats_len; |
| |
| /* Add TLS extension EllipticCurves to the ClientHello message */ |
| tls1_get_curvelist(s, 0, &curves, &curves_len); |
| |
| lenmax = limit - ret - 6; |
| if (lenmax < 0) { |
| return NULL; |
| } |
| if (curves_len * 2 > (size_t)lenmax) { |
| return NULL; |
| } |
| if (curves_len * 2 > 65532) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_clienthello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_elliptic_curves, ret); |
| s2n((curves_len * 2) + 2, ret); |
| |
| s2n(curves_len * 2, ret); |
| for (i = 0; i < curves_len; i++) { |
| s2n(curves[i], ret); |
| } |
| } |
| |
| if (header_len > 0) { |
| size_t clienthello_minsize = 0; |
| header_len += ret - orig; |
| if (header_len > 0xff && header_len < 0x200) { |
| /* Add padding to workaround bugs in F5 terminators. See |
| * https://tools.ietf.org/html/draft-agl-tls-padding-03 |
| * |
| * NB: because this code works out the length of all existing extensions |
| * it MUST always appear last. */ |
| clienthello_minsize = 0x200; |
| } |
| if (s->fastradio_padding) { |
| /* Pad the ClientHello record to 1024 bytes to fast forward the radio |
| * into DCH (high data rate) state in 3G networks. Note that when |
| * fastradio_padding is enabled, even if the header_len is less than 255 |
| * bytes, the padding will be applied regardless. This is slightly |
| * different from the TLS padding extension suggested in |
| * https://tools.ietf.org/html/draft-agl-tls-padding-03 */ |
| clienthello_minsize = 0x400; |
| } |
| if (header_len < clienthello_minsize) { |
| size_t padding_len = clienthello_minsize - header_len; |
| /* Extensions take at least four bytes to encode. Always include least |
| * one byte of data if including the extension. WebSphere Application |
| * Server 7.0 is intolerant to the last extension being zero-length. */ |
| if (padding_len >= 4 + 1) { |
| padding_len -= 4; |
| } else { |
| padding_len = 1; |
| } |
| |
| if (limit - ret - 4 - (long)padding_len < 0) { |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_padding, ret); |
| s2n(padding_len, ret); |
| memset(ret, 0, padding_len); |
| ret += padding_len; |
| } |
| } |
| |
| extdatalen = ret - orig - 2; |
| if (extdatalen == 0) { |
| return orig; |
| } |
| |
| s2n(extdatalen, orig); |
| return ret; |
| } |
| |
| uint8_t *ssl_add_serverhello_tlsext(SSL *s, uint8_t *const buf, |
| uint8_t *const limit) { |
| int extdatalen = 0; |
| uint8_t *orig = buf; |
| uint8_t *ret = buf; |
| int next_proto_neg_seen; |
| uint32_t alg_k = s->s3->tmp.new_cipher->algorithm_mkey; |
| uint32_t alg_a = s->s3->tmp.new_cipher->algorithm_auth; |
| int using_ecc = (alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA); |
| using_ecc = using_ecc && (s->s3->tmp.peer_ecpointformatlist != NULL); |
| |
| /* don't add extensions for SSLv3, unless doing secure renegotiation */ |
| if (s->version == SSL3_VERSION && !s->s3->send_connection_binding) { |
| return orig; |
| } |
| |
| ret += 2; |
| if (ret >= limit) { |
| return NULL; /* should never happen. */ |
| } |
| |
| CBB cbb; |
| if (!CBB_init_fixed(&cbb, ret, limit - ret)) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_serverhello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| |
| unsigned i; |
| for (i = 0; i < kNumExtensions; i++) { |
| if (!(s->s3->tmp.extensions.received & (1u << i))) { |
| /* Don't send extensions that were not received. */ |
| continue; |
| } |
| |
| if (!kExtensions[i].add_serverhello(s, &cbb)) { |
| CBB_cleanup(&cbb); |
| OPENSSL_PUT_ERROR(SSL, ssl_add_serverhello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| } |
| |
| ret += CBB_len(&cbb); |
| CBB_cleanup(&cbb); |
| |
| if (s->s3->tmp.extended_master_secret) { |
| if ((long)(limit - ret - 4) < 0) { |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_extended_master_secret, ret); |
| s2n(0, ret); |
| } |
| |
| if (using_ecc) { |
| const uint8_t *plist; |
| size_t plistlen; |
| /* Add TLS extension ECPointFormats to the ServerHello message */ |
| long lenmax; |
| |
| tls1_get_formatlist(s, &plist, &plistlen); |
| |
| lenmax = limit - ret - 5; |
| if (lenmax < 0) { |
| return NULL; |
| } |
| if (plistlen > (size_t)lenmax) { |
| return NULL; |
| } |
| if (plistlen > 255) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_serverhello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_ec_point_formats, ret); |
| s2n(plistlen + 1, ret); |
| *(ret++) = (uint8_t)plistlen; |
| memcpy(ret, plist, plistlen); |
| ret += plistlen; |
| } |
| /* Currently the server should not respond with a SupportedCurves extension */ |
| |
| if (s->tlsext_ticket_expected && !(SSL_get_options(s) & SSL_OP_NO_TICKET)) { |
| if ((long)(limit - ret - 4) < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_session_ticket, ret); |
| s2n(0, ret); |
| } |
| |
| if (s->s3->tmp.certificate_status_expected) { |
| if ((long)(limit - ret - 4) < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_status_request, ret); |
| s2n(0, ret); |
| } |
| |
| if (s->srtp_profile) { |
| int el; |
| |
| ssl_add_serverhello_use_srtp_ext(s, 0, &el, 0); |
| |
| if ((limit - ret - 4 - el) < 0) { |
| return NULL; |
| } |
| |
| s2n(TLSEXT_TYPE_use_srtp, ret); |
| s2n(el, ret); |
| |
| if (!ssl_add_serverhello_use_srtp_ext(s, ret, &el, el)) { |
| OPENSSL_PUT_ERROR(SSL, ssl_add_serverhello_tlsext, ERR_R_INTERNAL_ERROR); |
| return NULL; |
| } |
| ret += el; |
| } |
| |
| next_proto_neg_seen = s->s3->next_proto_neg_seen; |
| s->s3->next_proto_neg_seen = 0; |
| if (next_proto_neg_seen && s->ctx->next_protos_advertised_cb) { |
| const uint8_t *npa; |
| unsigned int npalen; |
| int r; |
| |
| r = s->ctx->next_protos_advertised_cb( |
| s, &npa, &npalen, s->ctx->next_protos_advertised_cb_arg); |
| if (r == SSL_TLSEXT_ERR_OK) { |
| if ((long)(limit - ret - 4 - npalen) < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_next_proto_neg, ret); |
| s2n(npalen, ret); |
| memcpy(ret, npa, npalen); |
| ret += npalen; |
| s->s3->next_proto_neg_seen = 1; |
| } |
| } |
| |
| if (s->s3->alpn_selected) { |
| const uint8_t *selected = s->s3->alpn_selected; |
| size_t len = s->s3->alpn_selected_len; |
| |
| if ((long)(limit - ret - 4 - 2 - 1 - len) < 0) { |
| return NULL; |
| } |
| s2n(TLSEXT_TYPE_application_layer_protocol_negotiation, ret); |
| s2n(3 + len, ret); |
| s2n(1 + len, ret); |
| *ret++ = len; |
| memcpy(ret, selected, len); |
| ret += len; |
| } |
| |
| /* If the client advertised support for Channel ID, and we have it |
| * enabled, then we want to echo it back. */ |
| if (s->s3->tlsext_channel_id_valid) { |
| if (limit - ret - 4 < 0) { |
| return NULL; |
| } |
| if (s->s3->tlsext_channel_id_new) { |
| s2n(TLSEXT_TYPE_channel_id_new, ret); |
| } else { |
| s2n(TLSEXT_TYPE_channel_id, ret); |
| } |
| s2n(0, ret); |
| } |
| |
| extdatalen = ret - orig - 2; |
| if (extdatalen == 0) { |
| return orig; |
| } |
| |
| s2n(extdatalen, orig); |
| return ret; |
| } |
| |
| /* tls1_alpn_handle_client_hello is called to process the ALPN extension in a |
| * ClientHello. |
| * cbs: the contents of the extension, not including the type and length. |
| * out_alert: a pointer to the alert value to send in the event of a zero |
| * return. |
| * |
| * returns: 1 on success. */ |
| static int tls1_alpn_handle_client_hello(SSL *s, CBS *cbs, int *out_alert) { |
| CBS protocol_name_list, protocol_name_list_copy; |
| const uint8_t *selected; |
| uint8_t selected_len; |
| int r; |
| |
| if (s->ctx->alpn_select_cb == NULL) { |
| return 1; |
| } |
| |
| if (!CBS_get_u16_length_prefixed(cbs, &protocol_name_list) || |
| CBS_len(cbs) != 0 || CBS_len(&protocol_name_list) < 2) { |
| goto parse_error; |
| } |
| |
| /* Validate the protocol list. */ |
| protocol_name_list_copy = protocol_name_list; |
| while (CBS_len(&protocol_name_list_copy) > 0) { |
| CBS protocol_name; |
| |
| if (!CBS_get_u8_length_prefixed(&protocol_name_list_copy, &protocol_name) || |
| /* Empty protocol names are forbidden. */ |
| CBS_len(&protocol_name) == 0) { |
| goto parse_error; |
| } |
| } |
| |
| r = s->ctx->alpn_select_cb( |
| s, &selected, &selected_len, CBS_data(&protocol_name_list), |
| CBS_len(&protocol_name_list), s->ctx->alpn_select_cb_arg); |
| if (r == SSL_TLSEXT_ERR_OK) { |
| OPENSSL_free(s->s3->alpn_selected); |
| s->s3->alpn_selected = BUF_memdup(selected, selected_len); |
| if (!s->s3->alpn_selected) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| s->s3->alpn_selected_len = selected_len; |
| } |
| |
| return 1; |
| |
| parse_error: |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| static int ssl_scan_clienthello_tlsext(SSL *s, CBS *cbs, int *out_alert) { |
| CBS extensions; |
| |
| s->srtp_profile = NULL; |
| s->s3->next_proto_neg_seen = 0; |
| s->s3->tmp.certificate_status_expected = 0; |
| s->s3->tmp.extended_master_secret = 0; |
| |
| OPENSSL_free(s->s3->alpn_selected); |
| s->s3->alpn_selected = NULL; |
| |
| /* Clear any signature algorithms extension received */ |
| OPENSSL_free(s->cert->peer_sigalgs); |
| s->cert->peer_sigalgs = NULL; |
| s->cert->peer_sigalgslen = 0; |
| |
| /* Clear any shared signature algorithms */ |
| OPENSSL_free(s->cert->shared_sigalgs); |
| s->cert->shared_sigalgs = NULL; |
| s->cert->shared_sigalgslen = 0; |
| |
| /* Clear ECC extensions */ |
| OPENSSL_free(s->s3->tmp.peer_ecpointformatlist); |
| s->s3->tmp.peer_ecpointformatlist = NULL; |
| s->s3->tmp.peer_ecpointformatlist_length = 0; |
| |
| OPENSSL_free(s->s3->tmp.peer_ellipticcurvelist); |
| s->s3->tmp.peer_ellipticcurvelist = NULL; |
| s->s3->tmp.peer_ellipticcurvelist_length = 0; |
| |
| size_t i; |
| for (i = 0; i < kNumExtensions; i++) { |
| if (kExtensions[i].init != NULL) { |
| kExtensions[i].init(s); |
| } |
| } |
| |
| s->s3->tmp.extensions.received = 0; |
| /* The renegotiation extension must always be at index zero because the |
| * |received| and |sent| bitsets need to be tweaked when the "extension" is |
| * sent as an SCSV. */ |
| assert(kExtensions[0].value == TLSEXT_TYPE_renegotiate); |
| |
| /* There may be no extensions. */ |
| if (CBS_len(cbs) == 0) { |
| goto no_extensions; |
| } |
| |
| /* Decode the extensions block and check it is valid. */ |
| if (!CBS_get_u16_length_prefixed(cbs, &extensions) || |
| !tls1_check_duplicate_extensions(&extensions)) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| while (CBS_len(&extensions) != 0) { |
| uint16_t type; |
| CBS extension; |
| |
| /* Decode the next extension. */ |
| if (!CBS_get_u16(&extensions, &type) || |
| !CBS_get_u16_length_prefixed(&extensions, &extension)) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| unsigned ext_index; |
| const struct tls_extension *const ext = |
| tls_extension_find(&ext_index, type); |
| |
| if (ext != NULL) { |
| s->s3->tmp.extensions.received |= (1u << ext_index); |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!ext->parse_clienthello(s, &alert, &extension)) { |
| *out_alert = alert; |
| return 0; |
| } |
| |
| continue; |
| } |
| |
| if (type == TLSEXT_TYPE_ec_point_formats) { |
| CBS ec_point_format_list; |
| |
| if (!CBS_get_u8_length_prefixed(&extension, &ec_point_format_list) || |
| CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| if (!CBS_stow(&ec_point_format_list, &s->s3->tmp.peer_ecpointformatlist, |
| &s->s3->tmp.peer_ecpointformatlist_length)) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_elliptic_curves) { |
| CBS elliptic_curve_list; |
| size_t num_curves; |
| |
| if (!CBS_get_u16_length_prefixed(&extension, &elliptic_curve_list) || |
| CBS_len(&elliptic_curve_list) == 0 || |
| (CBS_len(&elliptic_curve_list) & 1) != 0 || |
| CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| OPENSSL_free(s->s3->tmp.peer_ellipticcurvelist); |
| s->s3->tmp.peer_ellipticcurvelist_length = 0; |
| |
| s->s3->tmp.peer_ellipticcurvelist = |
| (uint16_t *)OPENSSL_malloc(CBS_len(&elliptic_curve_list)); |
| |
| if (s->s3->tmp.peer_ellipticcurvelist == NULL) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| num_curves = CBS_len(&elliptic_curve_list) / 2; |
| for (i = 0; i < num_curves; i++) { |
| if (!CBS_get_u16(&elliptic_curve_list, |
| &s->s3->tmp.peer_ellipticcurvelist[i])) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| } |
| |
| if (CBS_len(&elliptic_curve_list) != 0) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| s->s3->tmp.peer_ellipticcurvelist_length = num_curves; |
| } else if (type == TLSEXT_TYPE_signature_algorithms) { |
| CBS supported_signature_algorithms; |
| |
| if (!CBS_get_u16_length_prefixed(&extension, |
| &supported_signature_algorithms) || |
| CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| /* Ensure the signature algorithms are non-empty. It contains a list of |
| * SignatureAndHashAlgorithms which are two bytes each. */ |
| if (CBS_len(&supported_signature_algorithms) == 0 || |
| (CBS_len(&supported_signature_algorithms) % 2) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| if (!tls1_process_sigalgs(s, &supported_signature_algorithms)) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| /* If sigalgs received and no shared algorithms fatal error. */ |
| if (s->cert->peer_sigalgs && !s->cert->shared_sigalgs) { |
| OPENSSL_PUT_ERROR(SSL, ssl_scan_clienthello_tlsext, |
| SSL_R_NO_SHARED_SIGATURE_ALGORITHMS); |
| *out_alert = SSL_AD_ILLEGAL_PARAMETER; |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_next_proto_neg && |
| !s->s3->initial_handshake_complete && |
| s->s3->alpn_selected == NULL && !SSL_IS_DTLS(s)) { |
| /* The extension must be empty. */ |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| s->s3->next_proto_neg_seen = 1; |
| } else if (type == TLSEXT_TYPE_application_layer_protocol_negotiation && |
| s->ctx->alpn_select_cb && !s->s3->initial_handshake_complete) { |
| if (!tls1_alpn_handle_client_hello(s, &extension, out_alert)) { |
| return 0; |
| } |
| /* ALPN takes precedence over NPN. */ |
| s->s3->next_proto_neg_seen = 0; |
| } else if (type == TLSEXT_TYPE_channel_id && s->tlsext_channel_id_enabled && |
| !SSL_IS_DTLS(s)) { |
| /* The extension must be empty. */ |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| s->s3->tlsext_channel_id_valid = 1; |
| } else if (type == TLSEXT_TYPE_channel_id_new && |
| s->tlsext_channel_id_enabled && !SSL_IS_DTLS(s)) { |
| /* The extension must be empty. */ |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| s->s3->tlsext_channel_id_valid = 1; |
| s->s3->tlsext_channel_id_new = 1; |
| } else if (type == TLSEXT_TYPE_use_srtp) { |
| if (!ssl_parse_clienthello_use_srtp_ext(s, &extension, out_alert)) { |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_extended_master_secret && |
| s->version != SSL3_VERSION) { |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| s->s3->tmp.extended_master_secret = 1; |
| } |
| } |
| |
| no_extensions: |
| for (i = 0; i < kNumExtensions; i++) { |
| if (!(s->s3->tmp.extensions.received & (1u << i))) { |
| /* Extension wasn't observed so call the callback with a NULL |
| * parameter. */ |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!kExtensions[i].parse_clienthello(s, &alert, NULL)) { |
| *out_alert = alert; |
| return 0; |
| } |
| } |
| } |
| |
| return 1; |
| } |
| |
| int ssl_parse_clienthello_tlsext(SSL *s, CBS *cbs) { |
| int alert = -1; |
| if (ssl_scan_clienthello_tlsext(s, cbs, &alert) <= 0) { |
| ssl3_send_alert(s, SSL3_AL_FATAL, alert); |
| return 0; |
| } |
| |
| if (ssl_check_clienthello_tlsext(s) <= 0) { |
| OPENSSL_PUT_ERROR(SSL, ssl_parse_clienthello_tlsext, |
| SSL_R_CLIENTHELLO_TLSEXT); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* ssl_next_proto_validate validates a Next Protocol Negotiation block. No |
| * elements of zero length are allowed and the set of elements must exactly |
| * fill the length of the block. */ |
| static char ssl_next_proto_validate(const CBS *cbs) { |
| CBS copy = *cbs; |
| |
| while (CBS_len(©) != 0) { |
| CBS proto; |
| if (!CBS_get_u8_length_prefixed(©, &proto) || CBS_len(&proto) == 0) { |
| return 0; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static int ssl_scan_serverhello_tlsext(SSL *s, CBS *cbs, int *out_alert) { |
| CBS extensions; |
| |
| /* TODO(davidben): Move all of these to some per-handshake state that gets |
| * systematically reset on a new handshake; perhaps allocate it fresh each |
| * time so it's not even kept around post-handshake. */ |
| s->s3->next_proto_neg_seen = 0; |
| s->tlsext_ticket_expected = 0; |
| s->s3->tmp.certificate_status_expected = 0; |
| s->s3->tmp.extended_master_secret = 0; |
| s->srtp_profile = NULL; |
| |
| OPENSSL_free(s->s3->alpn_selected); |
| s->s3->alpn_selected = NULL; |
| |
| /* Clear ECC extensions */ |
| OPENSSL_free(s->s3->tmp.peer_ecpointformatlist); |
| s->s3->tmp.peer_ecpointformatlist = NULL; |
| s->s3->tmp.peer_ecpointformatlist_length = 0; |
| |
| uint32_t received = 0; |
| size_t i; |
| assert(kNumExtensions <= sizeof(received) * 8); |
| |
| /* There may be no extensions. */ |
| if (CBS_len(cbs) == 0) { |
| goto no_extensions; |
| } |
| |
| /* Decode the extensions block and check it is valid. */ |
| if (!CBS_get_u16_length_prefixed(cbs, &extensions) || |
| !tls1_check_duplicate_extensions(&extensions)) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| while (CBS_len(&extensions) != 0) { |
| uint16_t type; |
| CBS extension; |
| |
| /* Decode the next extension. */ |
| if (!CBS_get_u16(&extensions, &type) || |
| !CBS_get_u16_length_prefixed(&extensions, &extension)) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| unsigned ext_index; |
| const struct tls_extension *const ext = |
| tls_extension_find(&ext_index, type); |
| |
| /* While we have extensions that don't use tls_extension this conditional |
| * needs to be guarded on |ext != NULL|. In the future, ext being NULL will |
| * be fatal. */ |
| if (ext != NULL) { |
| if (!(s->s3->tmp.extensions.sent & (1u << ext_index))) { |
| /* Received an extension that was never sent. */ |
| OPENSSL_PUT_ERROR(SSL, ssl_scan_serverhello_tlsext, |
| SSL_R_UNEXPECTED_EXTENSION); |
| ERR_add_error_dataf("ext:%u", (unsigned) type); |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| received |= (1u << ext_index); |
| |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!ext->parse_serverhello(s, &alert, &extension)) { |
| *out_alert = alert; |
| return 0; |
| } |
| |
| continue; |
| } |
| |
| if (type == TLSEXT_TYPE_ec_point_formats) { |
| CBS ec_point_format_list; |
| |
| if (!CBS_get_u8_length_prefixed(&extension, &ec_point_format_list) || |
| CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| if (!CBS_stow(&ec_point_format_list, &s->s3->tmp.peer_ecpointformatlist, |
| &s->s3->tmp.peer_ecpointformatlist_length)) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_session_ticket) { |
| if ((SSL_get_options(s) & SSL_OP_NO_TICKET) || CBS_len(&extension) > 0) { |
| *out_alert = SSL_AD_UNSUPPORTED_EXTENSION; |
| return 0; |
| } |
| |
| s->tlsext_ticket_expected = 1; |
| } else if (type == TLSEXT_TYPE_status_request) { |
| /* The extension MUST be empty and may only sent if we've requested a |
| * status request message. */ |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| if (!s->ocsp_stapling_enabled) { |
| *out_alert = SSL_AD_UNSUPPORTED_EXTENSION; |
| return 0; |
| } |
| |
| /* Set a flag to expect a CertificateStatus message */ |
| s->s3->tmp.certificate_status_expected = 1; |
| } else if (type == TLSEXT_TYPE_next_proto_neg && |
| !s->s3->initial_handshake_complete && !SSL_IS_DTLS(s)) { |
| uint8_t *selected; |
| uint8_t selected_len; |
| |
| /* We must have requested it. */ |
| if (s->ctx->next_proto_select_cb == NULL) { |
| *out_alert = SSL_AD_UNSUPPORTED_EXTENSION; |
| return 0; |
| } |
| |
| /* The data must be valid. */ |
| if (!ssl_next_proto_validate(&extension)) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| if (s->ctx->next_proto_select_cb( |
| s, &selected, &selected_len, CBS_data(&extension), |
| CBS_len(&extension), |
| s->ctx->next_proto_select_cb_arg) != SSL_TLSEXT_ERR_OK) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| s->next_proto_negotiated = BUF_memdup(selected, selected_len); |
| if (s->next_proto_negotiated == NULL) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| |
| s->next_proto_negotiated_len = selected_len; |
| s->s3->next_proto_neg_seen = 1; |
| } else if (type == TLSEXT_TYPE_application_layer_protocol_negotiation && |
| !s->s3->initial_handshake_complete) { |
| CBS protocol_name_list, protocol_name; |
| |
| /* We must have requested it. */ |
| if (s->alpn_client_proto_list == NULL) { |
| *out_alert = SSL_AD_UNSUPPORTED_EXTENSION; |
| return 0; |
| } |
| |
| /* The extension data consists of a ProtocolNameList which must have |
| * exactly one ProtocolName. Each of these is length-prefixed. */ |
| if (!CBS_get_u16_length_prefixed(&extension, &protocol_name_list) || |
| CBS_len(&extension) != 0 || |
| !CBS_get_u8_length_prefixed(&protocol_name_list, &protocol_name) || |
| /* Empty protocol names are forbidden. */ |
| CBS_len(&protocol_name) == 0 || |
| CBS_len(&protocol_name_list) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| if (!CBS_stow(&protocol_name, &s->s3->alpn_selected, |
| &s->s3->alpn_selected_len)) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_channel_id && !SSL_IS_DTLS(s)) { |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| s->s3->tlsext_channel_id_valid = 1; |
| } else if (type == TLSEXT_TYPE_channel_id_new && !SSL_IS_DTLS(s)) { |
| if (CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| s->s3->tlsext_channel_id_valid = 1; |
| s->s3->tlsext_channel_id_new = 1; |
| } else if (type == TLSEXT_TYPE_certificate_timestamp) { |
| if (CBS_len(&extension) == 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| /* Session resumption uses the original session information. */ |
| if (!s->hit && |
| !CBS_stow(&extension, &s->session->tlsext_signed_cert_timestamp_list, |
| &s->session->tlsext_signed_cert_timestamp_list_length)) { |
| *out_alert = SSL_AD_INTERNAL_ERROR; |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_use_srtp) { |
| if (!ssl_parse_serverhello_use_srtp_ext(s, &extension, out_alert)) { |
| return 0; |
| } |
| } else if (type == TLSEXT_TYPE_extended_master_secret) { |
| if (/* It is invalid for the server to select EMS and |
| SSLv3. */ |
| s->version == SSL3_VERSION || CBS_len(&extension) != 0) { |
| *out_alert = SSL_AD_DECODE_ERROR; |
| return 0; |
| } |
| |
| s->s3->tmp.extended_master_secret = 1; |
| } |
| } |
| |
| no_extensions: |
| for (i = 0; i < kNumExtensions; i++) { |
| if (!(received & (1u << i))) { |
| /* Extension wasn't observed so call the callback with a NULL |
| * parameter. */ |
| uint8_t alert = SSL_AD_DECODE_ERROR; |
| if (!kExtensions[i].parse_serverhello(s, &alert, NULL)) { |
| *out_alert = alert; |
| return 0; |
| } |
| } |
| } |
| |
| return 1; |
| } |
| |
| int ssl_prepare_clienthello_tlsext(SSL *s) { return 1; } |
| |
| int ssl_prepare_serverhello_tlsext(SSL *s) { return 1; } |
| |
| static int ssl_check_clienthello_tlsext(SSL *s) { |
| int ret = SSL_TLSEXT_ERR_NOACK; |
| int al = SSL_AD_UNRECOGNIZED_NAME; |
| |
| /* The handling of the ECPointFormats extension is done elsewhere, namely in |
| * ssl3_choose_cipher in s3_lib.c. */ |
| |
| if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) { |
| ret = s->ctx->tlsext_servername_callback(s, &al, |
| s->ctx->tlsext_servername_arg); |
| } else if (s->initial_ctx != NULL && |
| s->initial_ctx->tlsext_servername_callback != 0) { |
| ret = s->initial_ctx->tlsext_servername_callback( |
| s, &al, s->initial_ctx->tlsext_servername_arg); |
| } |
| |
| switch (ret) { |
| case SSL_TLSEXT_ERR_ALERT_FATAL: |
| ssl3_send_alert(s, SSL3_AL_FATAL, al); |
| return -1; |
| |
| case SSL_TLSEXT_ERR_ALERT_WARNING: |
| ssl3_send_alert(s, SSL3_AL_WARNING, al); |
| return 1; |
| |
| case SSL_TLSEXT_ERR_NOACK: |
| s->s3->tmp.should_ack_sni = 0; |
| return 1; |
| |
| default: |
| return 1; |
| } |
| } |
| |
| static int ssl_check_serverhello_tlsext(SSL *s) { |
| int ret = SSL_TLSEXT_ERR_NOACK; |
| int al = SSL_AD_UNRECOGNIZED_NAME; |
| |
| /* If we are client and using an elliptic curve cryptography cipher suite, |
| * then if server returns an EC point formats lists extension it must contain |
| * uncompressed. */ |
| uint32_t alg_k = s->s3->tmp.new_cipher->algorithm_mkey; |
| uint32_t alg_a = s->s3->tmp.new_cipher->algorithm_auth; |
| if (((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA)) && |
| !tls1_check_point_format(s, TLSEXT_ECPOINTFORMAT_uncompressed)) { |
| OPENSSL_PUT_ERROR(SSL, ssl_check_serverhello_tlsext, |
| SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST); |
| return -1; |
| } |
| ret = SSL_TLSEXT_ERR_OK; |
| |
| if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) { |
| ret = s->ctx->tlsext_servername_callback(s, &al, |
| s->ctx->tlsext_servername_arg); |
| } else if (s->initial_ctx != NULL && |
| s->initial_ctx->tlsext_servername_callback != 0) { |
| ret = s->initial_ctx->tlsext_servername_callback( |
| s, &al, s->initial_ctx->tlsext_servername_arg); |
| } |
| |
| switch (ret) { |
| case SSL_TLSEXT_ERR_ALERT_FATAL: |
| ssl3_send_alert(s, SSL3_AL_FATAL, al); |
| return -1; |
| |
| case SSL_TLSEXT_ERR_ALERT_WARNING: |
| ssl3_send_alert(s, SSL3_AL_WARNING, al); |
| return 1; |
| |
| default: |
| return 1; |
| } |
| } |
| |
| int ssl_parse_serverhello_tlsext(SSL *s, CBS *cbs) { |
| int alert = -1; |
| if (s->version < SSL3_VERSION) { |
| return 1; |
| } |
| |
| if (ssl_scan_serverhello_tlsext(s, cbs, &alert) <= 0) { |
| ssl3_send_alert(s, SSL3_AL_FATAL, alert); |
| return 0; |
| } |
| |
| if (ssl_check_serverhello_tlsext(s) <= 0) { |
| OPENSSL_PUT_ERROR(SSL, ssl_parse_serverhello_tlsext, |
| SSL_R_SERVERHELLO_TLSEXT); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| int tls_process_ticket(SSL *ssl, SSL_SESSION **out_session, |
| int *out_send_ticket, const uint8_t *ticket, |
| size_t ticket_len, const uint8_t *session_id, |
| size_t session_id_len) { |
| int ret = 1; /* Most errors are non-fatal. */ |
| SSL_CTX *ssl_ctx = ssl->initial_ctx; |
| uint8_t *plaintext = NULL; |
| |
| HMAC_CTX hmac_ctx; |
| HMAC_CTX_init(&hmac_ctx); |
| EVP_CIPHER_CTX cipher_ctx; |
| EVP_CIPHER_CTX_init(&cipher_ctx); |
| |
| *out_send_ticket = 0; |
| *out_session = NULL; |
| |
| if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) { |
| goto done; |
| } |
| |
| if (ticket_len == 0) { |
| /* The client will accept a ticket but doesn't currently have one. */ |
| *out_send_ticket = 1; |
| goto done; |
| } |
| |
| /* Ensure there is room for the key name and the largest IV |
| * |tlsext_ticket_key_cb| may try to consume. The real limit may be lower, but |
| * the maximum IV length should be well under the minimum size for the |
| * session material and HMAC. */ |
| if (ticket_len < SSL_TICKET_KEY_NAME_LEN + EVP_MAX_IV_LENGTH) { |
| goto done; |
| } |
| const uint8_t *iv = ticket + SSL_TICKET_KEY_NAME_LEN; |
| |
| if (ssl_ctx->tlsext_ticket_key_cb != NULL) { |
| int cb_ret = ssl_ctx->tlsext_ticket_key_cb(ssl, (uint8_t*)ticket /* name */, |
| (uint8_t*)iv, &cipher_ctx, &hmac_ctx, |
| 0 /* decrypt */); |
| if (cb_ret < 0) { |
| ret = 0; |
| goto done; |
| } |
| if (cb_ret == 0) { |
| goto done; |
| } |
| if (cb_ret == 2) { |
| *out_send_ticket = 1; |
| } |
| } else { |
| /* Check the key name matches. */ |
| if (memcmp(ticket, ssl_ctx->tlsext_tick_key_name, |
| SSL_TICKET_KEY_NAME_LEN) != 0) { |
| goto done; |
| } |
| if (!HMAC_Init_ex(&hmac_ctx, ssl_ctx->tlsext_tick_hmac_key, |
| sizeof(ssl_ctx->tlsext_tick_hmac_key), tlsext_tick_md(), |
| NULL) || |
| !EVP_DecryptInit_ex(&cipher_ctx, EVP_aes_128_cbc(), NULL, |
| ssl_ctx->tlsext_tick_aes_key, iv)) { |
| ret = 0; |
| goto done; |
| } |
| } |
| size_t iv_len = EVP_CIPHER_CTX_iv_length(&cipher_ctx); |
| |
| /* Check the MAC at the end of the ticket. */ |
| uint8_t mac[EVP_MAX_MD_SIZE]; |
| size_t mac_len = HMAC_size(&hmac_ctx); |
| if (ticket_len < SSL_TICKET_KEY_NAME_LEN + iv_len + 1 + mac_len) { |
| /* The ticket must be large enough for key name, IV, data, and MAC. */ |
| goto done; |
| } |
| HMAC_Update(&hmac_ctx, ticket, ticket_len - mac_len); |
| HMAC_Final(&hmac_ctx, mac, NULL); |
| if (CRYPTO_memcmp(mac, ticket + (ticket_len - mac_len), mac_len) != 0) { |
| goto done; |
| } |
| |
| /* Decrypt the session data. */ |
| const uint8_t *ciphertext = ticket + SSL_TICKET_KEY_NAME_LEN + iv_len; |
| size_t ciphertext_len = ticket_len - SSL_TICKET_KEY_NAME_LEN - iv_len - |
| mac_len; |
| plaintext = OPENSSL_malloc(ciphertext_len); |
| if (plaintext == NULL) { |
| ret = 0; |
| goto done; |
| } |
| if (ciphertext_len >= INT_MAX) { |
| goto done; |
| } |
| int len1, len2; |
| if (!EVP_DecryptUpdate(&cipher_ctx, plaintext, &len1, ciphertext, |
| (int)ciphertext_len) || |
| !EVP_DecryptFinal_ex(&cipher_ctx, plaintext + len1, &len2)) { |
| ERR_clear_error(); /* Don't leave an error on the queue. */ |
| goto done; |
| } |
| |
| /* Decode the session. */ |
| SSL_SESSION *session = SSL_SESSION_from_bytes(plaintext, len1 + len2); |
| if (session == NULL) { |
| ERR_clear_error(); /* Don't leave an error on the queue. */ |
| goto done; |
| } |
| |
| /* Copy the client's session ID into the new session, to denote the ticket has |
| * been accepted. */ |
| memcpy(session->session_id, session_id, session_id_len); |
| session->session_id_length = session_id_len; |
| |
| *out_session = session; |
| |
| done: |
| OPENSSL_free(plaintext); |
| HMAC_CTX_cleanup(&hmac_ctx); |
| EVP_CIPHER_CTX_cleanup(&cipher_ctx); |
| return ret; |
| } |
| |
| /* Tables to translate from NIDs to TLS v1.2 ids */ |
| typedef struct { |
| int nid; |
| int id; |
| } tls12_lookup; |
| |
| static const tls12_lookup tls12_md[] = {{NID_md5, TLSEXT_hash_md5}, |
| {NID_sha1, TLSEXT_hash_sha1}, |
| {NID_sha224, TLSEXT_hash_sha224}, |
| {NID_sha256, TLSEXT_hash_sha256}, |
| {NID_sha384, TLSEXT_hash_sha384}, |
| {NID_sha512, TLSEXT_hash_sha512}}; |
| |
| static const tls12_lookup tls12_sig[] = {{EVP_PKEY_RSA, TLSEXT_signature_rsa}, |
| {EVP_PKEY_EC, TLSEXT_signature_ecdsa}}; |
| |
| static int tls12_find_id(int nid, const 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; |
| } |
| |
| int tls12_get_sigid(int pkey_type) { |
| return tls12_find_id(pkey_type, tls12_sig, |
| sizeof(tls12_sig) / sizeof(tls12_lookup)); |
| } |
| |
| int tls12_get_sigandhash(SSL *ssl, uint8_t *p, 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(ssl_private_key_type(ssl)); |
| if (sig_id == -1) { |
| return 0; |
| } |
| |
| p[0] = (uint8_t)md_id; |
| p[1] = (uint8_t)sig_id; |
| return 1; |
| } |
| |
| const EVP_MD *tls12_get_hash(uint8_t hash_alg) { |
| switch (hash_alg) { |
| case TLSEXT_hash_md5: |
| return EVP_md5(); |
| |
| case TLSEXT_hash_sha1: |
| return EVP_sha1(); |
| |
| case TLSEXT_hash_sha224: |
| return EVP_sha224(); |
| |
| case TLSEXT_hash_sha256: |
| return EVP_sha256(); |
| |
| case TLSEXT_hash_sha384: |
| return EVP_sha384(); |
| |
| case TLSEXT_hash_sha512: |
| return EVP_sha512(); |
| |
| default: |
| return NULL; |
| } |
| } |
| |
| /* tls12_get_pkey_type returns the EVP_PKEY type corresponding to TLS signature |
| * algorithm |sig_alg|. It returns -1 if the type is unknown. */ |
| static int tls12_get_pkey_type(uint8_t sig_alg) { |
| switch (sig_alg) { |
| case TLSEXT_signature_rsa: |
| return EVP_PKEY_RSA; |
| |
| case TLSEXT_signature_ecdsa: |
| return EVP_PKEY_EC; |
| |
| default: |
| return -1; |
| } |
| } |
| |
| /* Given preference and allowed sigalgs set shared sigalgs */ |
| static int tls12_do_shared_sigalgs(TLS_SIGALGS *shsig, const uint8_t *pref, |
| size_t preflen, const uint8_t *allow, |
| size_t allowlen) { |
| const uint8_t *ptmp, *atmp; |
| size_t i, j, nmatch = 0; |
| |
| for (i = 0, ptmp = pref; i < preflen; i += 2, ptmp += 2) { |
| /* Skip disabled hashes or signature algorithms */ |
| if (tls12_get_hash(ptmp[0]) == NULL || |
| tls12_get_pkey_type(ptmp[1]) == -1) { |
| continue; |
| } |
| |
| for (j = 0, atmp = allow; j < allowlen; j += 2, atmp += 2) { |
| if (ptmp[0] == atmp[0] && ptmp[1] == atmp[1]) { |
| nmatch++; |
| if (shsig) { |
| shsig->rhash = ptmp[0]; |
| shsig->rsign = ptmp[1]; |
| shsig++; |
| } |
| |
| break; |
| } |
| } |
| } |
| |
| return nmatch; |
| } |
| |
| /* Set shared signature algorithms for SSL structures */ |
| static int tls1_set_shared_sigalgs(SSL *s) { |
| const uint8_t *pref, *allow, *conf; |
| size_t preflen, allowlen, conflen; |
| size_t nmatch; |
| TLS_SIGALGS *salgs = NULL; |
| CERT *c = s->cert; |
| |
| OPENSSL_free(c->shared_sigalgs); |
| c->shared_sigalgs = NULL; |
| c->shared_sigalgslen = 0; |
| |
| /* If client use client signature algorithms if not NULL */ |
| if (!s->server && c->client_sigalgs) { |
| conf = c->client_sigalgs; |
| conflen = c->client_sigalgslen; |
| } else if (c->conf_sigalgs) { |
| conf = c->conf_sigalgs; |
| conflen = c->conf_sigalgslen; |
| } else { |
| conflen = tls12_get_psigalgs(s, &conf); |
| } |
| |
| if (s->options & SSL_OP_CIPHER_SERVER_PREFERENCE) { |
| pref = conf; |
| preflen = conflen; |
| allow = c->peer_sigalgs; |
| allowlen = c->peer_sigalgslen; |
| } else { |
| allow = conf; |
| allowlen = conflen; |
| pref = c->peer_sigalgs; |
| preflen = c->peer_sigalgslen; |
| } |
| |
| nmatch = tls12_do_shared_sigalgs(NULL, pref, preflen, allow, allowlen); |
| if (!nmatch) { |
| return 1; |
| } |
| |
| salgs = OPENSSL_malloc(nmatch * sizeof(TLS_SIGALGS)); |
| if (!salgs) { |
| return 0; |
| } |
| |
| nmatch = tls12_do_shared_sigalgs(salgs, pref, preflen, allow, allowlen); |
| c->shared_sigalgs = salgs; |
| c->shared_sigalgslen = nmatch; |
| return 1; |
| } |
| |
| /* Set preferred digest for each key type */ |
| int tls1_process_sigalgs(SSL *s, const CBS *sigalgs) { |
| CERT *c = s->cert; |
| |
| /* Extension ignored for inappropriate versions */ |
| if (!SSL_USE_SIGALGS(s)) { |
| return 1; |
| } |
| |
| if (CBS_len(sigalgs) % 2 != 0 || |
| !CBS_stow(sigalgs, &c->peer_sigalgs, &c->peer_sigalgslen) || |
| !tls1_set_shared_sigalgs(s)) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| const EVP_MD *tls1_choose_signing_digest(SSL *ssl) { |
| CERT *cert = ssl->cert; |
| int type = ssl_private_key_type(ssl); |
| size_t i; |
| |
| /* Select the first shared digest supported by our key. */ |
| for (i = 0; i < cert->shared_sigalgslen; i++) { |
| const EVP_MD *md = tls12_get_hash(cert->shared_sigalgs[i].rhash); |
| if (md == NULL || |
| tls12_get_pkey_type(cert->shared_sigalgs[i].rsign) != type || |
| !ssl_private_key_supports_digest(ssl, md)) { |
| continue; |
| } |
| return md; |
| } |
| |
| /* If no suitable digest may be found, default to SHA-1. */ |
| return EVP_sha1(); |
| } |
| |
| /* tls1_channel_id_hash calculates the signed data for a Channel ID on the |
| * given SSL connection and writes it to |md|. */ |
| int tls1_channel_id_hash(EVP_MD_CTX *md, SSL *s) { |
| EVP_MD_CTX ctx; |
| uint8_t temp_digest[EVP_MAX_MD_SIZE]; |
| unsigned temp_digest_len; |
| int i; |
| static const char kClientIDMagic[] = "TLS Channel ID signature"; |
| |
| if (s->s3->handshake_buffer && |
| !ssl3_digest_cached_records(s, free_handshake_buffer)) { |
| return 0; |
| } |
| |
| EVP_DigestUpdate(md, kClientIDMagic, sizeof(kClientIDMagic)); |
| |
| if (s->hit && s->s3->tlsext_channel_id_new) { |
| static const char kResumptionMagic[] = "Resumption"; |
| EVP_DigestUpdate(md, kResumptionMagic, sizeof(kResumptionMagic)); |
| if (s->session->original_handshake_hash_len == 0) { |
| return 0; |
| } |
| EVP_DigestUpdate(md, s->session->original_handshake_hash, |
| s->session->original_handshake_hash_len); |
| } |
| |
| EVP_MD_CTX_init(&ctx); |
| for (i = 0; i < SSL_MAX_DIGEST; i++) { |
| if (s->s3->handshake_dgst[i] == NULL) { |
| continue; |
| } |
| if (!EVP_MD_CTX_copy_ex(&ctx, s->s3->handshake_dgst[i])) { |
| EVP_MD_CTX_cleanup(&ctx); |
| return 0; |
| } |
| EVP_DigestFinal_ex(&ctx, temp_digest, &temp_digest_len); |
| EVP_DigestUpdate(md, temp_digest, temp_digest_len); |
| } |
| EVP_MD_CTX_cleanup(&ctx); |
| |
| return 1; |
| } |
| |
| /* tls1_record_handshake_hashes_for_channel_id records the current handshake |
| * hashes in |s->session| so that Channel ID resumptions can sign that data. */ |
| int tls1_record_handshake_hashes_for_channel_id(SSL *s) { |
| int digest_len; |
| /* This function should never be called for a resumed session because the |
| * handshake hashes that we wish to record are for the original, full |
| * handshake. */ |
| if (s->hit) { |
| return -1; |
| } |
| |
| /* It only makes sense to call this function if Channel IDs have been |
| * negotiated. */ |
| if (!s->s3->tlsext_channel_id_new) { |
| return -1; |
| } |
| |
| digest_len = |
| tls1_handshake_digest(s, s->session->original_handshake_hash, |
| sizeof(s->session->original_handshake_hash)); |
| if (digest_len < 0) { |
| return -1; |
| } |
| |
| s->session->original_handshake_hash_len = digest_len; |
| |
| return 1; |
| } |
| |
| int tls1_set_sigalgs(CERT *c, const int *psig_nids, size_t salglen, |
| int client) { |
| uint8_t *sigalgs, *sptr; |
| int rhash, rsign; |
| size_t i; |
| |
| if (salglen & 1) { |
| return 0; |
| } |
| |
| sigalgs = OPENSSL_malloc(salglen); |
| if (sigalgs == NULL) { |
| return 0; |
| } |
| |
| for (i = 0, sptr = sigalgs; i < salglen; i += 2) { |
| rhash = tls12_find_id(*psig_nids++, tls12_md, |
| sizeof(tls12_md) / sizeof(tls12_lookup)); |
| rsign = tls12_find_id(*psig_nids++, tls12_sig, |
| sizeof(tls12_sig) / sizeof(tls12_lookup)); |
| |
| if (rhash == -1 || rsign == -1) { |
| goto err; |
| } |
| *sptr++ = rhash; |
| *sptr++ = rsign; |
| } |
| |
| if (client) { |
| OPENSSL_free(c->client_sigalgs); |
| c->client_sigalgs = sigalgs; |
| c->client_sigalgslen = salglen; |
| } else { |
| OPENSSL_free(c->conf_sigalgs); |
| c->conf_sigalgs = sigalgs; |
| c->conf_sigalgslen = salglen; |
| } |
| |
| return 1; |
| |
| err: |
| OPENSSL_free(sigalgs); |
| return 0; |
| } |