• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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