v3_scts.c revision 326663 
1/* v3_scts.c */
2/*
3 * Written by Rob Stradling (rob@comodo.com) for the OpenSSL project 2014.
4 */
5/* ====================================================================
6 * Copyright (c) 2014 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
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
18 *    distribution.
19 *
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/)"
24 *
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.
29 *
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.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
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 * ====================================================================
52 *
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).
56 *
57 */
58
59#include <stdio.h>
60#include "cryptlib.h"
61#include <openssl/asn1.h>
62#include <openssl/x509v3.h>
63
64/* Signature and hash algorithms from RFC 5246 */
65#define TLSEXT_hash_sha256                              4
66
67#define TLSEXT_signature_rsa                            1
68#define TLSEXT_signature_ecdsa                          3
69
70
71#define n2s(c,s)        ((s=(((unsigned int)(c[0]))<< 8)| \
72                            (((unsigned int)(c[1]))    )),c+=2)
73
74#if (defined(_WIN32) || defined(_WIN64)) && !defined(__MINGW32__)
75# define SCT_TIMESTAMP unsigned __int64
76#elif defined(__arch64__)
77# define SCT_TIMESTAMP unsigned long
78#else
79# define SCT_TIMESTAMP unsigned long long
80#endif
81
82#define n2l8(c,l)       (l =((SCT_TIMESTAMP)(*((c)++)))<<56, \
83                         l|=((SCT_TIMESTAMP)(*((c)++)))<<48, \
84                         l|=((SCT_TIMESTAMP)(*((c)++)))<<40, \
85                         l|=((SCT_TIMESTAMP)(*((c)++)))<<32, \
86                         l|=((SCT_TIMESTAMP)(*((c)++)))<<24, \
87                         l|=((SCT_TIMESTAMP)(*((c)++)))<<16, \
88                         l|=((SCT_TIMESTAMP)(*((c)++)))<< 8, \
89                         l|=((SCT_TIMESTAMP)(*((c)++))))
90
91typedef struct SCT_st {
92    /* The encoded SCT */
93    unsigned char *sct;
94    unsigned short sctlen;
95    /*
96     * Components of the SCT.  "logid", "ext" and "sig" point to addresses
97     * inside "sct".
98     */
99    unsigned char version;
100    unsigned char *logid;
101    unsigned short logidlen;
102    SCT_TIMESTAMP timestamp;
103    unsigned char *ext;
104    unsigned short extlen;
105    unsigned char hash_alg;
106    unsigned char sig_alg;
107    unsigned char *sig;
108    unsigned short siglen;
109} SCT;
110
111DECLARE_STACK_OF(SCT)
112
113static void SCT_LIST_free(STACK_OF(SCT) *a);
114static STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a,
115                                   const unsigned char **pp, long length);
116static int i2r_SCT_LIST(X509V3_EXT_METHOD *method, STACK_OF(SCT) *sct_list,
117                        BIO *out, int indent);
118
119const X509V3_EXT_METHOD v3_ct_scts[] = {
120    {NID_ct_precert_scts, 0, NULL,
121     0, (X509V3_EXT_FREE)SCT_LIST_free,
122     (X509V3_EXT_D2I)d2i_SCT_LIST, 0,
123     0, 0, 0, 0,
124     (X509V3_EXT_I2R)i2r_SCT_LIST, 0,
125     NULL},
126
127    {NID_ct_cert_scts, 0, NULL,
128     0, (X509V3_EXT_FREE)SCT_LIST_free,
129     (X509V3_EXT_D2I)d2i_SCT_LIST, 0,
130     0, 0, 0, 0,
131     (X509V3_EXT_I2R)i2r_SCT_LIST, 0,
132     NULL},
133};
134
135static void tls12_signature_print(BIO *out, const unsigned char hash_alg,
136                                  const unsigned char sig_alg)
137{
138    int nid = NID_undef;
139    /* RFC6962 only permits two signature algorithms */
140    if (hash_alg == TLSEXT_hash_sha256) {
141        if (sig_alg == TLSEXT_signature_rsa)
142            nid = NID_sha256WithRSAEncryption;
143        else if (sig_alg == TLSEXT_signature_ecdsa)
144            nid = NID_ecdsa_with_SHA256;
145    }
146    if (nid == NID_undef)
147        BIO_printf(out, "%02X%02X", hash_alg, sig_alg);
148    else
149        BIO_printf(out, "%s", OBJ_nid2ln(nid));
150}
151
152static void timestamp_print(BIO *out, SCT_TIMESTAMP timestamp)
153{
154    ASN1_GENERALIZEDTIME *gen;
155    char genstr[20];
156    gen = ASN1_GENERALIZEDTIME_new();
157    ASN1_GENERALIZEDTIME_adj(gen, (time_t)0,
158                             (int)(timestamp / 86400000),
159                             (int)(timestamp % 86400000) / 1000);
160    /*
161     * Note GeneralizedTime from ASN1_GENERALIZETIME_adj is always 15
162     * characters long with a final Z. Update it with fractional seconds.
163     */
164    BIO_snprintf(genstr, sizeof(genstr), "%.14s.%03dZ",
165                 ASN1_STRING_data(gen), (unsigned int)(timestamp % 1000));
166    ASN1_GENERALIZEDTIME_set_string(gen, genstr);
167    ASN1_GENERALIZEDTIME_print(out, gen);
168    ASN1_GENERALIZEDTIME_free(gen);
169}
170
171static void SCT_free(SCT *sct)
172{
173    if (sct) {
174        if (sct->sct)
175            OPENSSL_free(sct->sct);
176        OPENSSL_free(sct);
177    }
178}
179
180static void SCT_LIST_free(STACK_OF(SCT) *a)
181{
182    sk_SCT_pop_free(a, SCT_free);
183}
184
185static STACK_OF(SCT) *d2i_SCT_LIST(STACK_OF(SCT) **a,
186                                   const unsigned char **pp, long length)
187{
188    ASN1_OCTET_STRING *oct = NULL;
189    STACK_OF(SCT) *sk = NULL;
190    SCT *sct;
191    unsigned char *p, *p2;
192    unsigned short listlen, sctlen = 0, fieldlen;
193    const unsigned char *q = *pp;
194
195    if (d2i_ASN1_OCTET_STRING(&oct, &q, length) == NULL)
196        return NULL;
197    if (oct->length < 2)
198        goto done;
199    p = oct->data;
200    n2s(p, listlen);
201    if (listlen != oct->length - 2)
202        goto done;
203
204    if ((sk = sk_SCT_new_null()) == NULL)
205        goto done;
206
207    while (listlen > 0) {
208        if (listlen < 2)
209            goto err;
210        n2s(p, sctlen);
211        listlen -= 2;
212
213        if ((sctlen < 1) || (sctlen > listlen))
214            goto err;
215        listlen -= sctlen;
216
217        sct = OPENSSL_malloc(sizeof(SCT));
218        if (!sct)
219            goto err;
220        if (!sk_SCT_push(sk, sct)) {
221            OPENSSL_free(sct);
222            goto err;
223        }
224
225        sct->sct = OPENSSL_malloc(sctlen);
226        if (!sct->sct)
227            goto err;
228        memcpy(sct->sct, p, sctlen);
229        sct->sctlen = sctlen;
230        p += sctlen;
231        p2 = sct->sct;
232
233        sct->version = *p2++;
234        if (sct->version == 0) { /* SCT v1 */
235            /*-
236             * Fixed-length header:
237             *              struct {
238             * (1 byte)       Version sct_version;
239             * (32 bytes)     LogID id;
240             * (8 bytes)      uint64 timestamp;
241             * (2 bytes + ?)  CtExtensions extensions;
242             */
243            if (sctlen < 43)
244                goto err;
245            sctlen -= 43;
246
247            sct->logid = p2;
248            sct->logidlen = 32;
249            p2 += 32;
250
251            n2l8(p2, sct->timestamp);
252
253            n2s(p2, fieldlen);
254            if (sctlen < fieldlen)
255                goto err;
256            sct->ext = p2;
257            sct->extlen = fieldlen;
258            p2 += fieldlen;
259            sctlen -= fieldlen;
260
261            /*-
262             * digitally-signed struct header:
263             * (1 byte)       Hash algorithm
264             * (1 byte)       Signature algorithm
265             * (2 bytes + ?)  Signature
266             */
267            if (sctlen < 4)
268                goto err;
269            sctlen -= 4;
270
271            sct->hash_alg = *p2++;
272            sct->sig_alg = *p2++;
273            n2s(p2, fieldlen);
274            if (sctlen != fieldlen)
275                goto err;
276            sct->sig = p2;
277            sct->siglen = fieldlen;
278        }
279    }
280
281 done:
282    ASN1_OCTET_STRING_free(oct);
283    *pp = q;
284    return sk;
285
286 err:
287    SCT_LIST_free(sk);
288    sk = NULL;
289    goto done;
290}
291
292static int i2r_SCT_LIST(X509V3_EXT_METHOD *method, STACK_OF(SCT) *sct_list,
293                        BIO *out, int indent)
294{
295    SCT *sct;
296    int i;
297
298    for (i = 0; i < sk_SCT_num(sct_list);) {
299        sct = sk_SCT_value(sct_list, i);
300
301        BIO_printf(out, "%*sSigned Certificate Timestamp:", indent, "");
302        BIO_printf(out, "\n%*sVersion   : ", indent + 4, "");
303
304        if (sct->version == 0) { /* SCT v1 */
305            BIO_printf(out, "v1(0)");
306
307            BIO_printf(out, "\n%*sLog ID    : ", indent + 4, "");
308            BIO_hex_string(out, indent + 16, 16, sct->logid, sct->logidlen);
309
310            BIO_printf(out, "\n%*sTimestamp : ", indent + 4, "");
311            timestamp_print(out, sct->timestamp);
312
313            BIO_printf(out, "\n%*sExtensions: ", indent + 4, "");
314            if (sct->extlen == 0)
315                BIO_printf(out, "none");
316            else
317                BIO_hex_string(out, indent + 16, 16, sct->ext, sct->extlen);
318
319            BIO_printf(out, "\n%*sSignature : ", indent + 4, "");
320            tls12_signature_print(out, sct->hash_alg, sct->sig_alg);
321            BIO_printf(out, "\n%*s            ", indent + 4, "");
322            BIO_hex_string(out, indent + 16, 16, sct->sig, sct->siglen);
323        } else {                /* Unknown version */
324
325            BIO_printf(out, "unknown\n%*s", indent + 16, "");
326            BIO_hex_string(out, indent + 16, 16, sct->sct, sct->sctlen);
327        }
328
329        if (++i < sk_SCT_num(sct_list))
330            BIO_printf(out, "\n");
331    }
332
333    return 1;
334}
335