1 /* Copyright (c) 2017, Google Inc.
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14
15 #include <openssl/pkcs7.h>
16
17 #include <assert.h>
18 #include <limits.h>
19
20 #include <openssl/bytestring.h>
21 #include <openssl/err.h>
22 #include <openssl/mem.h>
23 #include <openssl/pem.h>
24 #include <openssl/pool.h>
25 #include <openssl/stack.h>
26 #include <openssl/x509.h>
27
28 #include "internal.h"
29
30
PKCS7_get_certificates(STACK_OF (X509)* out_certs,CBS * cbs)31 int PKCS7_get_certificates(STACK_OF(X509) *out_certs, CBS *cbs) {
32 int ret = 0;
33 const size_t initial_certs_len = sk_X509_num(out_certs);
34 STACK_OF(CRYPTO_BUFFER) *raw = sk_CRYPTO_BUFFER_new_null();
35 if (raw == NULL ||
36 !PKCS7_get_raw_certificates(raw, cbs, NULL)) {
37 goto err;
38 }
39
40 for (size_t i = 0; i < sk_CRYPTO_BUFFER_num(raw); i++) {
41 CRYPTO_BUFFER *buf = sk_CRYPTO_BUFFER_value(raw, i);
42 X509 *x509 = X509_parse_from_buffer(buf);
43 if (x509 == NULL ||
44 !sk_X509_push(out_certs, x509)) {
45 X509_free(x509);
46 goto err;
47 }
48 }
49
50 ret = 1;
51
52 err:
53 sk_CRYPTO_BUFFER_pop_free(raw, CRYPTO_BUFFER_free);
54 if (!ret) {
55 while (sk_X509_num(out_certs) != initial_certs_len) {
56 X509 *x509 = sk_X509_pop(out_certs);
57 X509_free(x509);
58 }
59 }
60
61 return ret;
62 }
63
PKCS7_get_CRLs(STACK_OF (X509_CRL)* out_crls,CBS * cbs)64 int PKCS7_get_CRLs(STACK_OF(X509_CRL) *out_crls, CBS *cbs) {
65 CBS signed_data, crls;
66 uint8_t *der_bytes = NULL;
67 int ret = 0;
68 const size_t initial_crls_len = sk_X509_CRL_num(out_crls);
69
70 if (!pkcs7_parse_header(&der_bytes, &signed_data, cbs)) {
71 return 0;
72 }
73
74 /* See https://tools.ietf.org/html/rfc2315#section-9.1 */
75
76 /* Even if only CRLs are included, there may be an empty certificates block.
77 * OpenSSL does this, for example. */
78 if (CBS_peek_asn1_tag(&signed_data,
79 CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 0) &&
80 !CBS_get_asn1(&signed_data, NULL /* certificates */,
81 CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 0)) {
82 goto err;
83 }
84
85 if (!CBS_get_asn1(&signed_data, &crls,
86 CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 1)) {
87 OPENSSL_PUT_ERROR(PKCS7, PKCS7_R_NO_CRLS_INCLUDED);
88 goto err;
89 }
90
91 while (CBS_len(&crls) > 0) {
92 CBS crl_data;
93 X509_CRL *crl;
94 const uint8_t *inp;
95
96 if (!CBS_get_asn1_element(&crls, &crl_data, CBS_ASN1_SEQUENCE)) {
97 goto err;
98 }
99
100 if (CBS_len(&crl_data) > LONG_MAX) {
101 goto err;
102 }
103 inp = CBS_data(&crl_data);
104 crl = d2i_X509_CRL(NULL, &inp, (long)CBS_len(&crl_data));
105 if (!crl) {
106 goto err;
107 }
108
109 assert(inp == CBS_data(&crl_data) + CBS_len(&crl_data));
110
111 if (sk_X509_CRL_push(out_crls, crl) == 0) {
112 X509_CRL_free(crl);
113 goto err;
114 }
115 }
116
117 ret = 1;
118
119 err:
120 OPENSSL_free(der_bytes);
121
122 if (!ret) {
123 while (sk_X509_CRL_num(out_crls) != initial_crls_len) {
124 X509_CRL_free(sk_X509_CRL_pop(out_crls));
125 }
126 }
127
128 return ret;
129 }
130
PKCS7_get_PEM_certificates(STACK_OF (X509)* out_certs,BIO * pem_bio)131 int PKCS7_get_PEM_certificates(STACK_OF(X509) *out_certs, BIO *pem_bio) {
132 uint8_t *data;
133 long len;
134 int ret;
135
136 /* Even though we pass PEM_STRING_PKCS7 as the expected PEM type here, PEM
137 * internally will actually allow several other values too, including
138 * "CERTIFICATE". */
139 if (!PEM_bytes_read_bio(&data, &len, NULL /* PEM type output */,
140 PEM_STRING_PKCS7, pem_bio,
141 NULL /* password callback */,
142 NULL /* password callback argument */)) {
143 return 0;
144 }
145
146 CBS cbs;
147 CBS_init(&cbs, data, len);
148 ret = PKCS7_get_certificates(out_certs, &cbs);
149 OPENSSL_free(data);
150 return ret;
151 }
152
PKCS7_get_PEM_CRLs(STACK_OF (X509_CRL)* out_crls,BIO * pem_bio)153 int PKCS7_get_PEM_CRLs(STACK_OF(X509_CRL) *out_crls, BIO *pem_bio) {
154 uint8_t *data;
155 long len;
156 int ret;
157
158 /* Even though we pass PEM_STRING_PKCS7 as the expected PEM type here, PEM
159 * internally will actually allow several other values too, including
160 * "CERTIFICATE". */
161 if (!PEM_bytes_read_bio(&data, &len, NULL /* PEM type output */,
162 PEM_STRING_PKCS7, pem_bio,
163 NULL /* password callback */,
164 NULL /* password callback argument */)) {
165 return 0;
166 }
167
168 CBS cbs;
169 CBS_init(&cbs, data, len);
170 ret = PKCS7_get_CRLs(out_crls, &cbs);
171 OPENSSL_free(data);
172 return ret;
173 }
174
pkcs7_bundle_certificates_cb(CBB * out,const void * arg)175 static int pkcs7_bundle_certificates_cb(CBB *out, const void *arg) {
176 const STACK_OF(X509) *certs = arg;
177 size_t i;
178 CBB certificates;
179
180 /* See https://tools.ietf.org/html/rfc2315#section-9.1 */
181 if (!CBB_add_asn1(out, &certificates,
182 CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 0)) {
183 return 0;
184 }
185
186 for (i = 0; i < sk_X509_num(certs); i++) {
187 X509 *x509 = sk_X509_value(certs, i);
188 uint8_t *buf;
189 int len = i2d_X509(x509, NULL);
190
191 if (len < 0 ||
192 !CBB_add_space(&certificates, &buf, len) ||
193 i2d_X509(x509, &buf) < 0) {
194 return 0;
195 }
196 }
197
198 return CBB_flush(out);
199 }
200
PKCS7_bundle_certificates(CBB * out,const STACK_OF (X509)* certs)201 int PKCS7_bundle_certificates(CBB *out, const STACK_OF(X509) *certs) {
202 return pkcs7_bundle(out, pkcs7_bundle_certificates_cb, certs);
203 }
204
pkcs7_bundle_crls_cb(CBB * out,const void * arg)205 static int pkcs7_bundle_crls_cb(CBB *out, const void *arg) {
206 const STACK_OF(X509_CRL) *crls = arg;
207 size_t i;
208 CBB crl_data;
209
210 /* See https://tools.ietf.org/html/rfc2315#section-9.1 */
211 if (!CBB_add_asn1(out, &crl_data,
212 CBS_ASN1_CONTEXT_SPECIFIC | CBS_ASN1_CONSTRUCTED | 1)) {
213 return 0;
214 }
215
216 for (i = 0; i < sk_X509_CRL_num(crls); i++) {
217 X509_CRL *crl = sk_X509_CRL_value(crls, i);
218 uint8_t *buf;
219 int len = i2d_X509_CRL(crl, NULL);
220
221 if (len < 0 ||
222 !CBB_add_space(&crl_data, &buf, len) ||
223 i2d_X509_CRL(crl, &buf) < 0) {
224 return 0;
225 }
226 }
227
228 return CBB_flush(out);
229 }
230
PKCS7_bundle_CRLs(CBB * out,const STACK_OF (X509_CRL)* crls)231 int PKCS7_bundle_CRLs(CBB *out, const STACK_OF(X509_CRL) *crls) {
232 return pkcs7_bundle(out, pkcs7_bundle_crls_cb, crls);
233 }
234