2 /* ====================================================================
3 * Copyright (c) 2014 The OpenSSL Project. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the
17 * 3. All advertising materials mentioning features or use of this
18 * software must display the following acknowledgment:
19 * "This product includes software developed by the OpenSSL Project
20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 * endorse or promote products derived from this software without
24 * prior written permission. For written permission, please contact
25 * openssl-core@openssl.org.
27 * 5. Products derived from this software may not be called "OpenSSL"
28 * nor may "OpenSSL" appear in their names without prior written
29 * permission of the OpenSSL Project.
31 * 6. Redistributions of any form whatsoever must retain the following
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
50 * This product includes cryptographic software written by Eric Young
51 * (eay@cryptsoft.com). This product includes software written by Tim
52 * Hudson (tjh@cryptsoft.com).
56 /* Custom extension utility functions */
60 #ifndef OPENSSL_NO_TLSEXT
62 /* Find a custom extension from the list */
64 static custom_ext_method *custom_ext_find(custom_ext_methods *exts,
65 unsigned short ext_type)
68 custom_ext_method *meth = exts->meths;
69 for (i = 0; i < exts->meths_count; i++, meth++)
71 if (ext_type == meth->ext_type)
76 /* Initialise custom extensions flags to indicate neither sent nor
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 */
89 int custom_ext_parse(SSL *s, int server,
90 unsigned short ext_type,
91 const unsigned char *ext_data,
92 unsigned short ext_size,
95 custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
96 custom_ext_method *meth;
97 meth = custom_ext_find(exts, ext_type);
98 /* If not found or no parse function set, return success */
99 /* If not found return success */
104 /* If it's ServerHello we can't have any extensions not
105 * sent in ClientHello.
107 if (!(meth->ext_flags & SSL_EXT_FLAG_SENT))
109 *al = TLS1_AD_UNSUPPORTED_EXTENSION;
113 /* If already present it's a duplicate */
114 if (meth->ext_flags & SSL_EXT_FLAG_RECEIVED)
116 *al = TLS1_AD_DECODE_ERROR;
119 meth->ext_flags |= SSL_EXT_FLAG_RECEIVED;
123 return meth->parse_cb(s, ext_type, ext_data, ext_size, al, meth->arg);
126 /* request custom extension data from the application and add to the
130 int custom_ext_add(SSL *s, int server,
131 unsigned char **pret,
132 unsigned char *limit,
135 custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext;
136 custom_ext_method *meth;
137 unsigned char *ret = *pret;
140 for (i = 0; i < exts->meths_count; i++)
142 const unsigned char *out = NULL;
143 unsigned short outlen = 0;
144 meth = exts->meths + i;
148 /* For ServerHello only send extensions present
151 if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED))
153 /* If callback absent for server skip it */
160 cb_retval = meth->add_cb(s, meth->ext_type,
164 return 0; /* error */
166 continue; /* skip this extension */
168 if (4 > limit - ret || outlen > limit - ret - 4)
170 s2n(meth->ext_type, ret);
174 memcpy(ret, out, outlen);
177 /* We can't send duplicates: code logic should prevent this */
178 OPENSSL_assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT));
179 /* Indicate extension has been sent: this is both a sanity
180 * check to ensure we don't send duplicate extensions
181 * and indicates to servers that an extension can be
182 * sent in ServerHello.
184 meth->ext_flags |= SSL_EXT_FLAG_SENT;
190 /* Copy table of custom extensions */
192 int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src)
194 if (src->meths_count)
196 dst->meths = BUF_memdup(src->meths, sizeof(custom_ext_method) * src->meths_count);
197 if (dst->meths == NULL)
199 dst->meths_count = src->meths_count;
204 void custom_exts_free(custom_ext_methods *exts)
207 OPENSSL_free(exts->meths);
210 /* Set callbacks for a custom extension */
211 static int custom_ext_set(custom_ext_methods *exts,
212 unsigned short ext_type,
213 custom_ext_parse_cb parse_cb,
214 custom_ext_add_cb add_cb,
217 custom_ext_method *meth;
218 /* See if it is a supported internally */
221 case TLSEXT_TYPE_application_layer_protocol_negotiation:
222 case TLSEXT_TYPE_ec_point_formats:
223 case TLSEXT_TYPE_elliptic_curves:
224 case TLSEXT_TYPE_heartbeat:
225 case TLSEXT_TYPE_next_proto_neg:
226 case TLSEXT_TYPE_padding:
227 case TLSEXT_TYPE_renegotiate:
228 case TLSEXT_TYPE_server_name:
229 case TLSEXT_TYPE_session_ticket:
230 case TLSEXT_TYPE_signature_algorithms:
231 case TLSEXT_TYPE_srp:
232 case TLSEXT_TYPE_status_request:
233 case TLSEXT_TYPE_use_srtp:
234 #ifdef TLSEXT_TYPE_opaque_prf_input
235 case TLSEXT_TYPE_opaque_prf_input:
237 #ifdef TLSEXT_TYPE_encrypt_then_mac
238 case TLSEXT_TYPE_encrypt_then_mac:
242 /* Search for duplicate */
243 if (custom_ext_find(exts, ext_type))
245 exts->meths = OPENSSL_realloc(exts->meths,
246 (exts->meths_count + 1) * sizeof(custom_ext_method));
250 exts->meths_count = 0;
254 meth = exts->meths + exts->meths_count;
255 memset(meth, 0, sizeof(custom_ext_method));
256 meth->parse_cb = parse_cb;
257 meth->add_cb = add_cb;
258 meth->ext_type = ext_type;
264 /* Application level functions to add custom extension callbacks */
266 int SSL_CTX_set_custom_cli_ext(SSL_CTX *ctx, unsigned short ext_type,
267 custom_cli_ext_first_cb_fn fn1,
268 custom_cli_ext_second_cb_fn fn2, void *arg)
270 return custom_ext_set(&ctx->cert->cli_ext, ext_type, fn2, fn1, arg);
273 int SSL_CTX_set_custom_srv_ext(SSL_CTX *ctx, unsigned short ext_type,
274 custom_srv_ext_first_cb_fn fn1,
275 custom_srv_ext_second_cb_fn fn2, void *arg)
277 return custom_ext_set(&ctx->cert->srv_ext, ext_type, fn1, fn2, arg);