1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2 * All rights reserved.
3 *
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
7 *
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14 *
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50 * SUCH DAMAGE.
51 *
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.] */
56
57 #include <openssl/evp.h>
58
59 #include <string.h>
60
61 #include <openssl/bytestring.h>
62 #include <openssl/dsa.h>
63 #include <openssl/ec_key.h>
64 #include <openssl/err.h>
65 #include <openssl/rsa.h>
66
67 #include "internal.h"
68 #include "../internal.h"
69
70
71 static const EVP_PKEY_ASN1_METHOD *const kASN1Methods[] = {
72 &rsa_asn1_meth,
73 &ec_asn1_meth,
74 &dsa_asn1_meth,
75 &ed25519_asn1_meth,
76 };
77
parse_key_type(CBS * cbs,int * out_type)78 static int parse_key_type(CBS *cbs, int *out_type) {
79 CBS oid;
80 if (!CBS_get_asn1(cbs, &oid, CBS_ASN1_OBJECT)) {
81 return 0;
82 }
83
84 for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(kASN1Methods); i++) {
85 const EVP_PKEY_ASN1_METHOD *method = kASN1Methods[i];
86 if (CBS_len(&oid) == method->oid_len &&
87 OPENSSL_memcmp(CBS_data(&oid), method->oid, method->oid_len) == 0) {
88 *out_type = method->pkey_id;
89 return 1;
90 }
91 }
92
93 return 0;
94 }
95
EVP_parse_public_key(CBS * cbs)96 EVP_PKEY *EVP_parse_public_key(CBS *cbs) {
97 /* Parse the SubjectPublicKeyInfo. */
98 CBS spki, algorithm, key;
99 int type;
100 uint8_t padding;
101 if (!CBS_get_asn1(cbs, &spki, CBS_ASN1_SEQUENCE) ||
102 !CBS_get_asn1(&spki, &algorithm, CBS_ASN1_SEQUENCE) ||
103 !parse_key_type(&algorithm, &type) ||
104 !CBS_get_asn1(&spki, &key, CBS_ASN1_BITSTRING) ||
105 CBS_len(&spki) != 0 ||
106 /* Every key type defined encodes the key as a byte string with the same
107 * conversion to BIT STRING. */
108 !CBS_get_u8(&key, &padding) ||
109 padding != 0) {
110 OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);
111 return NULL;
112 }
113
114 /* Set up an |EVP_PKEY| of the appropriate type. */
115 EVP_PKEY *ret = EVP_PKEY_new();
116 if (ret == NULL ||
117 !EVP_PKEY_set_type(ret, type)) {
118 goto err;
119 }
120
121 /* Call into the type-specific SPKI decoding function. */
122 if (ret->ameth->pub_decode == NULL) {
123 OPENSSL_PUT_ERROR(EVP, EVP_R_UNSUPPORTED_ALGORITHM);
124 goto err;
125 }
126 if (!ret->ameth->pub_decode(ret, &algorithm, &key)) {
127 goto err;
128 }
129
130 return ret;
131
132 err:
133 EVP_PKEY_free(ret);
134 return NULL;
135 }
136
EVP_marshal_public_key(CBB * cbb,const EVP_PKEY * key)137 int EVP_marshal_public_key(CBB *cbb, const EVP_PKEY *key) {
138 if (key->ameth == NULL || key->ameth->pub_encode == NULL) {
139 OPENSSL_PUT_ERROR(EVP, EVP_R_UNSUPPORTED_ALGORITHM);
140 return 0;
141 }
142
143 return key->ameth->pub_encode(cbb, key);
144 }
145
EVP_parse_private_key(CBS * cbs)146 EVP_PKEY *EVP_parse_private_key(CBS *cbs) {
147 /* Parse the PrivateKeyInfo. */
148 CBS pkcs8, algorithm, key;
149 uint64_t version;
150 int type;
151 if (!CBS_get_asn1(cbs, &pkcs8, CBS_ASN1_SEQUENCE) ||
152 !CBS_get_asn1_uint64(&pkcs8, &version) ||
153 version != 0 ||
154 !CBS_get_asn1(&pkcs8, &algorithm, CBS_ASN1_SEQUENCE) ||
155 !parse_key_type(&algorithm, &type) ||
156 !CBS_get_asn1(&pkcs8, &key, CBS_ASN1_OCTETSTRING)) {
157 OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);
158 return NULL;
159 }
160
161 /* A PrivateKeyInfo ends with a SET of Attributes which we ignore. */
162
163 /* Set up an |EVP_PKEY| of the appropriate type. */
164 EVP_PKEY *ret = EVP_PKEY_new();
165 if (ret == NULL ||
166 !EVP_PKEY_set_type(ret, type)) {
167 goto err;
168 }
169
170 /* Call into the type-specific PrivateKeyInfo decoding function. */
171 if (ret->ameth->priv_decode == NULL) {
172 OPENSSL_PUT_ERROR(EVP, EVP_R_UNSUPPORTED_ALGORITHM);
173 goto err;
174 }
175 if (!ret->ameth->priv_decode(ret, &algorithm, &key)) {
176 goto err;
177 }
178
179 return ret;
180
181 err:
182 EVP_PKEY_free(ret);
183 return NULL;
184 }
185
EVP_marshal_private_key(CBB * cbb,const EVP_PKEY * key)186 int EVP_marshal_private_key(CBB *cbb, const EVP_PKEY *key) {
187 if (key->ameth == NULL || key->ameth->priv_encode == NULL) {
188 OPENSSL_PUT_ERROR(EVP, EVP_R_UNSUPPORTED_ALGORITHM);
189 return 0;
190 }
191
192 return key->ameth->priv_encode(cbb, key);
193 }
194
old_priv_decode(CBS * cbs,int type)195 static EVP_PKEY *old_priv_decode(CBS *cbs, int type) {
196 EVP_PKEY *ret = EVP_PKEY_new();
197 if (ret == NULL) {
198 return NULL;
199 }
200
201 switch (type) {
202 case EVP_PKEY_EC: {
203 EC_KEY *ec_key = EC_KEY_parse_private_key(cbs, NULL);
204 if (ec_key == NULL || !EVP_PKEY_assign_EC_KEY(ret, ec_key)) {
205 EC_KEY_free(ec_key);
206 goto err;
207 }
208 return ret;
209 }
210 case EVP_PKEY_DSA: {
211 DSA *dsa = DSA_parse_private_key(cbs);
212 if (dsa == NULL || !EVP_PKEY_assign_DSA(ret, dsa)) {
213 DSA_free(dsa);
214 goto err;
215 }
216 return ret;
217 }
218 case EVP_PKEY_RSA: {
219 RSA *rsa = RSA_parse_private_key(cbs);
220 if (rsa == NULL || !EVP_PKEY_assign_RSA(ret, rsa)) {
221 RSA_free(rsa);
222 goto err;
223 }
224 return ret;
225 }
226 default:
227 OPENSSL_PUT_ERROR(EVP, EVP_R_UNKNOWN_PUBLIC_KEY_TYPE);
228 goto err;
229 }
230
231 err:
232 EVP_PKEY_free(ret);
233 return NULL;
234 }
235
d2i_PrivateKey(int type,EVP_PKEY ** out,const uint8_t ** inp,long len)236 EVP_PKEY *d2i_PrivateKey(int type, EVP_PKEY **out, const uint8_t **inp,
237 long len) {
238 if (len < 0) {
239 OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);
240 return NULL;
241 }
242
243 /* Parse with the legacy format. */
244 CBS cbs;
245 CBS_init(&cbs, *inp, (size_t)len);
246 EVP_PKEY *ret = old_priv_decode(&cbs, type);
247 if (ret == NULL) {
248 /* Try again with PKCS#8. */
249 ERR_clear_error();
250 CBS_init(&cbs, *inp, (size_t)len);
251 ret = EVP_parse_private_key(&cbs);
252 if (ret == NULL) {
253 return NULL;
254 }
255 if (ret->type != type) {
256 OPENSSL_PUT_ERROR(EVP, EVP_R_DIFFERENT_KEY_TYPES);
257 EVP_PKEY_free(ret);
258 return NULL;
259 }
260 }
261
262 if (out != NULL) {
263 EVP_PKEY_free(*out);
264 *out = ret;
265 }
266 *inp = CBS_data(&cbs);
267 return ret;
268 }
269
270 /* num_elements parses one SEQUENCE from |in| and returns the number of elements
271 * in it. On parse error, it returns zero. */
num_elements(const uint8_t * in,size_t in_len)272 static size_t num_elements(const uint8_t *in, size_t in_len) {
273 CBS cbs, sequence;
274 CBS_init(&cbs, in, (size_t)in_len);
275
276 if (!CBS_get_asn1(&cbs, &sequence, CBS_ASN1_SEQUENCE)) {
277 return 0;
278 }
279
280 size_t count = 0;
281 while (CBS_len(&sequence) > 0) {
282 if (!CBS_get_any_asn1_element(&sequence, NULL, NULL, NULL)) {
283 return 0;
284 }
285
286 count++;
287 }
288
289 return count;
290 }
291
d2i_AutoPrivateKey(EVP_PKEY ** out,const uint8_t ** inp,long len)292 EVP_PKEY *d2i_AutoPrivateKey(EVP_PKEY **out, const uint8_t **inp, long len) {
293 if (len < 0) {
294 OPENSSL_PUT_ERROR(EVP, EVP_R_DECODE_ERROR);
295 return NULL;
296 }
297
298 /* Parse the input as a PKCS#8 PrivateKeyInfo. */
299 CBS cbs;
300 CBS_init(&cbs, *inp, (size_t)len);
301 EVP_PKEY *ret = EVP_parse_private_key(&cbs);
302 if (ret != NULL) {
303 if (out != NULL) {
304 EVP_PKEY_free(*out);
305 *out = ret;
306 }
307 *inp = CBS_data(&cbs);
308 return ret;
309 }
310 ERR_clear_error();
311
312 /* Count the elements to determine the legacy key format. */
313 switch (num_elements(*inp, (size_t)len)) {
314 case 4:
315 return d2i_PrivateKey(EVP_PKEY_EC, out, inp, len);
316
317 case 6:
318 return d2i_PrivateKey(EVP_PKEY_DSA, out, inp, len);
319
320 default:
321 return d2i_PrivateKey(EVP_PKEY_RSA, out, inp, len);
322 }
323 }
324
i2d_PublicKey(EVP_PKEY * key,uint8_t ** outp)325 int i2d_PublicKey(EVP_PKEY *key, uint8_t **outp) {
326 switch (key->type) {
327 case EVP_PKEY_RSA:
328 return i2d_RSAPublicKey(key->pkey.rsa, outp);
329 case EVP_PKEY_DSA:
330 return i2d_DSAPublicKey(key->pkey.dsa, outp);
331 case EVP_PKEY_EC:
332 return i2o_ECPublicKey(key->pkey.ec, outp);
333 default:
334 OPENSSL_PUT_ERROR(EVP, EVP_R_UNSUPPORTED_PUBLIC_KEY_TYPE);
335 return -1;
336 }
337 }
338