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
75 * Update encoding for SCT signature verification/generation to supplied
78 static int sct_ctx_update(EVP_MD_CTX *ctx, const SCT_CTX *sctx, const SCT *sct)
80 unsigned char tmpbuf[12];
81 unsigned char *p, *der;
84 * digitally-signed struct {
85 * (1 byte) Version sct_version;
86 * (1 byte) SignatureType signature_type = certificate_timestamp;
87 * (8 bytes) uint64 timestamp;
88 * (2 bytes) LogEntryType entry_type;
89 * (? bytes) select(entry_type) {
90 * case x509_entry: ASN.1Cert;
91 * case precert_entry: PreCert;
93 * (2 bytes + sct->ext_len) CtExtensions extensions;
96 if (sct->entry_type == CT_LOG_ENTRY_TYPE_NOT_SET)
98 if (sct->entry_type == CT_LOG_ENTRY_TYPE_PRECERT && sctx->ihash == NULL)
103 *p++ = SIGNATURE_TYPE_CERT_TIMESTAMP;
104 l2n8(sct->timestamp, p);
105 s2n(sct->entry_type, p);
107 if (!EVP_DigestUpdate(ctx, tmpbuf, p - tmpbuf))
110 if (sct->entry_type == CT_LOG_ENTRY_TYPE_X509) {
112 derlen = sctx->certderlen;
114 if (!EVP_DigestUpdate(ctx, sctx->ihash, sctx->ihashlen))
117 derlen = sctx->prederlen;
120 /* If no encoding available, fatal error */
124 /* Include length first */
128 if (!EVP_DigestUpdate(ctx, tmpbuf, 3))
130 if (!EVP_DigestUpdate(ctx, der, derlen))
133 /* Add any extensions */
135 s2n(sct->ext_len, p);
136 if (!EVP_DigestUpdate(ctx, tmpbuf, 2))
139 if (sct->ext_len && !EVP_DigestUpdate(ctx, sct->ext, sct->ext_len))
145 int SCT_verify(const SCT_CTX *sctx, const SCT *sct)
147 EVP_MD_CTX *ctx = NULL;
150 if (!SCT_is_complete(sct) || sctx->pkey == NULL ||
151 sct->entry_type == CT_LOG_ENTRY_TYPE_NOT_SET ||
152 (sct->entry_type == CT_LOG_ENTRY_TYPE_PRECERT && sctx->ihash == NULL)) {
153 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_NOT_SET);
156 if (sct->version != SCT_VERSION_V1) {
157 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_UNSUPPORTED_VERSION);
160 if (sct->log_id_len != sctx->pkeyhashlen ||
161 memcmp(sct->log_id, sctx->pkeyhash, sctx->pkeyhashlen) != 0) {
162 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_LOG_ID_MISMATCH);
166 ctx = EVP_MD_CTX_new();
170 if (!EVP_DigestVerifyInit(ctx, NULL, EVP_sha256(), NULL, sctx->pkey))
173 if (!sct_ctx_update(ctx, sctx, sct))
176 /* Verify signature */
177 ret = EVP_DigestVerifyFinal(ctx, sct->sig, sct->sig_len);
178 /* If ret < 0 some other error: fall through without setting error */
180 CTerr(CT_F_SCT_VERIFY, CT_R_SCT_INVALID_SIGNATURE);
183 EVP_MD_CTX_free(ctx);
187 int SCT_verify_v1(SCT *sct, X509 *cert, X509 *preissuer,
188 X509_PUBKEY *log_pubkey, X509 *issuer_cert)
191 SCT_CTX *sctx = NULL;
193 if (!SCT_is_complete(sct)) {
194 CTerr(CT_F_SCT_VERIFY_V1, CT_R_SCT_NOT_SET);
198 if (sct->version != 0) {
199 CTerr(CT_F_SCT_VERIFY_V1, CT_R_SCT_UNSUPPORTED_VERSION);
203 sctx = SCT_CTX_new();
207 ret = SCT_CTX_set1_pubkey(sctx, log_pubkey);
211 ret = SCT_CTX_set1_cert(sctx, cert, preissuer);
215 if (sct->entry_type == CT_LOG_ENTRY_TYPE_PRECERT) {
216 ret = SCT_CTX_set1_issuer(sctx, issuer_cert);
221 ret = SCT_verify(sctx, sct);