1 /* ====================================================================
2 * Copyright (c) 2014 The OpenSSL Project. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in
13 * the documentation and/or other materials provided with the
16 * 3. All advertising materials mentioning features or use of this
17 * software must display the following acknowledgment:
18 * "This product includes software developed by the OpenSSL Project
19 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
21 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
22 * endorse or promote products derived from this software without
23 * prior written permission. For written permission, please contact
24 * openssl-core@openssl.org.
26 * 5. Products derived from this software may not be called "OpenSSL"
27 * nor may "OpenSSL" appear in their names without prior written
28 * permission of the OpenSSL Project.
30 * 6. Redistributions of any form whatsoever must retain the following
32 * "This product includes software developed by the OpenSSL Project
33 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
35 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
38 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
46 * OF THE POSSIBILITY OF SUCH DAMAGE.
47 * ====================================================================
49 * This product includes cryptographic software written by Eric Young
50 * (eay@cryptsoft.com). This product includes software written by Tim
51 * Hudson (tjh@cryptsoft.com).
55 /* Custom extension utility functions */
58 # include <openssl/ct.h>
63 /* Find a custom extension from the list. */
64 static custom_ext_method *custom_ext_find(const custom_ext_methods *exts,
65 unsigned int ext_type)
68 custom_ext_method *meth = exts->meths;
69 for (i = 0; i < exts->meths_count; i++, meth++) {
70 if (ext_type == meth->ext_type)
77 * Initialise custom extensions flags to indicate neither sent nor received.
79 void custom_ext_init(custom_ext_methods *exts)
82 custom_ext_method *meth = exts->meths;
83 for (i = 0; i < exts->meths_count; i++, meth++)
87 /* Pass received custom extension data to the application for parsing. */
88 int custom_ext_parse(SSL *s, int server,
89 unsigned int ext_type,
90 const unsigned char *ext_data, size_t ext_size, int *al)
92 custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
93 custom_ext_method *meth;
94 meth = custom_ext_find(exts, ext_type);
95 /* If not found return success */
100 * If it's ServerHello we can't have any extensions not sent in
103 if (!(meth->ext_flags & SSL_EXT_FLAG_SENT)) {
104 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
108 /* If already present it's a duplicate */
109 if (meth->ext_flags & SSL_EXT_FLAG_RECEIVED) {
110 *al = TLS1_AD_DECODE_ERROR;
113 meth->ext_flags |= SSL_EXT_FLAG_RECEIVED;
114 /* If no parse function set return success */
118 return meth->parse_cb(s, ext_type, ext_data, ext_size, al,
123 * Request custom extension data from the application and add to the return
126 int custom_ext_add(SSL *s, int server,
127 unsigned char **pret, unsigned char *limit, int *al)
129 custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
130 custom_ext_method *meth;
131 unsigned char *ret = *pret;
134 for (i = 0; i < exts->meths_count; i++) {
135 const unsigned char *out = NULL;
137 meth = exts->meths + i;
141 * For ServerHello only send extensions present in ClientHello.
143 if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED))
145 /* If callback absent for server skip it */
151 cb_retval = meth->add_cb(s, meth->ext_type,
152 &out, &outlen, al, meth->add_arg);
154 return 0; /* error */
156 continue; /* skip this extension */
158 if (4 > limit - ret || outlen > (size_t)(limit - ret - 4))
160 s2n(meth->ext_type, ret);
163 memcpy(ret, out, outlen);
167 * We can't send duplicates: code logic should prevent this.
169 OPENSSL_assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT));
171 * Indicate extension has been sent: this is both a sanity check to
172 * ensure we don't send duplicate extensions and indicates that it is
173 * not an error if the extension is present in ServerHello.
175 meth->ext_flags |= SSL_EXT_FLAG_SENT;
177 meth->free_cb(s, meth->ext_type, out, meth->add_arg);
183 /* Copy table of custom extensions */
184 int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src)
186 if (src->meths_count) {
188 OPENSSL_memdup(src->meths,
189 sizeof(custom_ext_method) * src->meths_count);
190 if (dst->meths == NULL)
192 dst->meths_count = src->meths_count;
197 void custom_exts_free(custom_ext_methods *exts)
199 OPENSSL_free(exts->meths);
202 /* Set callbacks for a custom extension. */
203 static int custom_ext_meth_add(custom_ext_methods *exts,
204 unsigned int ext_type,
205 custom_ext_add_cb add_cb,
206 custom_ext_free_cb free_cb,
208 custom_ext_parse_cb parse_cb, void *parse_arg)
210 custom_ext_method *meth;
212 * Check application error: if add_cb is not set free_cb will never be
215 if (!add_cb && free_cb)
218 * Don't add if extension supported internally, but make exception
219 * for extension types that previously were not supported, but now are.
221 if (SSL_extension_supported(ext_type) &&
222 ext_type != TLSEXT_TYPE_signed_certificate_timestamp)
224 /* Extension type must fit in 16 bits */
225 if (ext_type > 0xffff)
227 /* Search for duplicate */
228 if (custom_ext_find(exts, ext_type))
230 exts->meths = OPENSSL_realloc(exts->meths,
232 1) * sizeof(custom_ext_method));
235 exts->meths_count = 0;
239 meth = exts->meths + exts->meths_count;
240 memset(meth, 0, sizeof(*meth));
241 meth->parse_cb = parse_cb;
242 meth->add_cb = add_cb;
243 meth->free_cb = free_cb;
244 meth->ext_type = ext_type;
245 meth->add_arg = add_arg;
246 meth->parse_arg = parse_arg;
251 /* Return true if a client custom extension exists, false otherwise */
252 int SSL_CTX_has_client_custom_ext(const SSL_CTX *ctx, unsigned int ext_type)
254 return custom_ext_find(&ctx->cert->cli_ext, ext_type) != NULL;
257 /* Application level functions to add custom extension callbacks */
258 int SSL_CTX_add_client_custom_ext(SSL_CTX *ctx, unsigned int ext_type,
259 custom_ext_add_cb add_cb,
260 custom_ext_free_cb free_cb,
262 custom_ext_parse_cb parse_cb,
265 int ret = custom_ext_meth_add(&ctx->cert->cli_ext, ext_type, add_cb,
266 free_cb, add_arg, parse_cb, parse_arg);
271 #ifndef OPENSSL_NO_CT
273 * We don't want applications registering callbacks for SCT extensions
274 * whilst simultaneously using the built-in SCT validation features, as
275 * these two things may not play well together.
277 if (ext_type == TLSEXT_TYPE_signed_certificate_timestamp &&
278 SSL_CTX_get_ct_validation_callback(ctx) != NULL) {
286 int SSL_CTX_add_server_custom_ext(SSL_CTX *ctx, unsigned int ext_type,
287 custom_ext_add_cb add_cb,
288 custom_ext_free_cb free_cb,
290 custom_ext_parse_cb parse_cb,
293 return custom_ext_meth_add(&ctx->cert->srv_ext, ext_type,
294 add_cb, free_cb, add_arg, parse_cb, parse_arg);
297 int SSL_extension_supported(unsigned int ext_type)
300 /* Internally supported extensions. */
301 case TLSEXT_TYPE_application_layer_protocol_negotiation:
302 case TLSEXT_TYPE_ec_point_formats:
303 case TLSEXT_TYPE_elliptic_curves:
304 case TLSEXT_TYPE_heartbeat:
305 case TLSEXT_TYPE_next_proto_neg:
306 case TLSEXT_TYPE_padding:
307 case TLSEXT_TYPE_renegotiate:
308 case TLSEXT_TYPE_server_name:
309 case TLSEXT_TYPE_session_ticket:
310 case TLSEXT_TYPE_signature_algorithms:
311 case TLSEXT_TYPE_srp:
312 case TLSEXT_TYPE_status_request:
313 case TLSEXT_TYPE_signed_certificate_timestamp:
314 case TLSEXT_TYPE_use_srtp:
315 #ifdef TLSEXT_TYPE_encrypt_then_mac
316 case TLSEXT_TYPE_encrypt_then_mac: