2 * Written by Rob Stradling (rob@comodo.com) and Stephen Henson
3 * (steve@openssl.org) for the OpenSSL project 2014.
5 /* ====================================================================
6 * Copyright (c) 2014 The OpenSSL Project. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * licensing@OpenSSL.org.
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
34 * 6. Redistributions of any form whatsoever must retain the following
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
61 #include <openssl/ct.h>
62 #include <openssl/err.h>
63 #include <openssl/evp.h>
64 #include <openssl/x509.h>
68 typedef enum sct_signature_type_t {
69 SIGNATURE_TYPE_NOT_SET = -1,
70 SIGNATURE_TYPE_CERT_TIMESTAMP,
71 SIGNATURE_TYPE_TREE_HASH
74 int CT_verify_no_bad_scts(const CT_POLICY_EVAL_CTX *ctx,
75 const STACK_OF(SCT) *scts, void *arg)
77 int sct_count = scts != NULL ? sk_SCT_num(scts) : 0;
80 for (i = 0; i < sct_count; ++i) {
81 SCT *sct = sk_SCT_value(scts, i);
83 switch (SCT_get_validation_status(sct)) {
84 case SCT_VALIDATION_STATUS_INVALID:
86 case SCT_VALIDATION_STATUS_NOT_SET:
87 CTerr(CT_F_CT_VERIFY_NO_BAD_SCTS,
88 CT_R_SCT_VALIDATION_STATUS_NOT_SET);
91 /* Ignore other validation statuses. */
99 int CT_verify_at_least_one_good_sct(const CT_POLICY_EVAL_CTX *ctx,
100 const STACK_OF(SCT) *scts, void *arg)
102 int sct_count = scts != NULL ? sk_SCT_num(scts) : 0;
106 for (i = 0; i < sct_count; ++i) {
107 SCT *sct = sk_SCT_value(scts, i);
109 switch (SCT_get_validation_status(sct)) {
110 case SCT_VALIDATION_STATUS_VALID:
113 case SCT_VALIDATION_STATUS_INVALID:
115 case SCT_VALIDATION_STATUS_NOT_SET:
116 CTerr(CT_F_CT_VERIFY_AT_LEAST_ONE_GOOD_SCT,
117 CT_R_SCT_VALIDATION_STATUS_NOT_SET);
120 /* Ignore other validation statuses. */
125 if (valid_scts == 0) {
126 CTerr(CT_F_CT_VERIFY_AT_LEAST_ONE_GOOD_SCT, CT_R_NOT_ENOUGH_SCTS);
134 * Update encoding for SCT signature verification/generation to supplied
137 static int sct_ctx_update(EVP_MD_CTX *ctx, const SCT_CTX *sctx, const SCT *sct)
139 unsigned char tmpbuf[12];
140 unsigned char *p, *der;
143 * digitally-signed struct {
144 * (1 byte) Version sct_version;
145 * (1 byte) SignatureType signature_type = certificate_timestamp;
146 * (8 bytes) uint64 timestamp;
147 * (2 bytes) LogEntryType entry_type;
148 * (? bytes) select(entry_type) {
149 * case x509_entry: ASN.1Cert;
150 * case precert_entry: PreCert;
152 * (2 bytes + sct->ext_len) CtExtensions extensions;
155 if (sct->entry_type == CT_LOG_ENTRY_TYPE_NOT_SET)
157 if (sct->entry_type == CT_LOG_ENTRY_TYPE_PRECERT && sctx->ihash == NULL)
162 *p++ = SIGNATURE_TYPE_CERT_TIMESTAMP;
163 l2n8(sct->timestamp, p);
164 s2n(sct->entry_type, p);
166 if (!EVP_DigestUpdate(ctx, tmpbuf, p - tmpbuf))
169 if (sct->entry_type == CT_LOG_ENTRY_TYPE_X509) {
171 derlen = sctx->certderlen;
173 if (!EVP_DigestUpdate(ctx, sctx->ihash, sctx->ihashlen))
176 derlen = sctx->prederlen;
179 /* If no encoding available, fatal error */
183 /* Include length first */
187 if (!EVP_DigestUpdate(ctx, tmpbuf, 3))
189 if (!EVP_DigestUpdate(ctx, der, derlen))
192 /* Add any extensions */
194 s2n(sct->ext_len, p);
195 if (!EVP_DigestUpdate(ctx, tmpbuf, 2))
198 if (sct->ext_len && !EVP_DigestUpdate(ctx, sct->ext, sct->ext_len))
204 int SCT_verify(const SCT_CTX *sctx, const SCT *sct)
206 EVP_MD_CTX *ctx = NULL;
209 if (!SCT_is_complete(sct) || sctx->pkey == NULL ||
210 sct->entry_type == CT_LOG_ENTRY_TYPE_NOT_SET ||
211 (sct->entry_type == CT_LOG_ENTRY_TYPE_PRECERT && sctx->ihash == NULL)) {
212 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_NOT_SET);
215 if (sct->version != SCT_VERSION_V1) {
216 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_UNSUPPORTED_VERSION);
219 if (sct->log_id_len != sctx->pkeyhashlen ||
220 memcmp(sct->log_id, sctx->pkeyhash, sctx->pkeyhashlen) != 0) {
221 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_LOG_ID_MISMATCH);
225 ctx = EVP_MD_CTX_new();
229 if (!EVP_DigestVerifyInit(ctx, NULL, EVP_sha256(), NULL, sctx->pkey))
232 if (!sct_ctx_update(ctx, sctx, sct))
235 /* Verify signature */
236 ret = EVP_DigestVerifyFinal(ctx, sct->sig, sct->sig_len);
237 /* If ret < 0 some other error: fall through without setting error */
239 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_INVALID_SIGNATURE);
242 EVP_MD_CTX_free(ctx);
246 int SCT_verify_v1(SCT *sct, X509 *cert, X509 *preissuer,
247 X509_PUBKEY *log_pubkey, X509 *issuer_cert)
250 SCT_CTX *sctx = NULL;
252 if (!SCT_is_complete(sct)) {
253 CTerr(CT_F_SCT_VERIFY_V1, CT_R_SCT_NOT_SET);
257 if (sct->version != 0) {
258 CTerr(CT_F_SCT_VERIFY_V1, CT_R_SCT_UNSUPPORTED_VERSION);
262 sctx = SCT_CTX_new();
266 ret = SCT_CTX_set1_pubkey(sctx, log_pubkey);
270 ret = SCT_CTX_set1_cert(sctx, cert, preissuer);
274 if (sct->entry_type == CT_LOG_ENTRY_TYPE_PRECERT) {
275 ret = SCT_CTX_set1_issuer(sctx, issuer_cert);
280 ret = SCT_verify(sctx, sct);