1 /*
2 * Copyright 2020-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <string.h>
11 #include <openssl/core_names.h>
12 #include <openssl/params.h>
13 #include <openssl/ec.h>
14 #include <openssl/rand.h>
15 #include <openssl/err.h>
16 #ifndef FIPS_MODULE
17 # include <openssl/x509.h>
18 #endif
19 #include "crypto/ecx.h"
20 #include "ecx_backend.h"
21
22 /*
23 * The intention with the "backend" source file is to offer backend support
24 * for legacy backends (EVP_PKEY_ASN1_METHOD and EVP_PKEY_METHOD) and provider
25 * implementations alike.
26 */
27
ossl_ecx_public_from_private(ECX_KEY * key)28 int ossl_ecx_public_from_private(ECX_KEY *key)
29 {
30 switch (key->type) {
31 case ECX_KEY_TYPE_X25519:
32 ossl_x25519_public_from_private(key->pubkey, key->privkey);
33 break;
34 case ECX_KEY_TYPE_ED25519:
35 if (!ossl_ed25519_public_from_private(key->libctx, key->pubkey,
36 key->privkey, key->propq)) {
37 ERR_raise(ERR_LIB_EC, EC_R_FAILED_MAKING_PUBLIC_KEY);
38 return 0;
39 }
40 break;
41 case ECX_KEY_TYPE_X448:
42 ossl_x448_public_from_private(key->pubkey, key->privkey);
43 break;
44 case ECX_KEY_TYPE_ED448:
45 if (!ossl_ed448_public_from_private(key->libctx, key->pubkey,
46 key->privkey, key->propq)) {
47 ERR_raise(ERR_LIB_EC, EC_R_FAILED_MAKING_PUBLIC_KEY);
48 return 0;
49 }
50 break;
51 }
52 return 1;
53 }
54
ossl_ecx_key_fromdata(ECX_KEY * ecx,const OSSL_PARAM params[],int include_private)55 int ossl_ecx_key_fromdata(ECX_KEY *ecx, const OSSL_PARAM params[],
56 int include_private)
57 {
58 size_t privkeylen = 0, pubkeylen = 0;
59 const OSSL_PARAM *param_priv_key = NULL, *param_pub_key;
60 unsigned char *pubkey;
61
62 if (ecx == NULL)
63 return 0;
64
65 param_pub_key = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PUB_KEY);
66 if (include_private)
67 param_priv_key =
68 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PRIV_KEY);
69
70 if (param_pub_key == NULL && param_priv_key == NULL)
71 return 0;
72
73 if (param_priv_key != NULL) {
74 if (!OSSL_PARAM_get_octet_string(param_priv_key,
75 (void **)&ecx->privkey, ecx->keylen,
76 &privkeylen))
77 return 0;
78 if (privkeylen != ecx->keylen) {
79 /*
80 * Invalid key length. We will clear what we've received now. We
81 * can't leave it to ossl_ecx_key_free() because that will call
82 * OPENSSL_secure_clear_free() and assume the correct key length
83 */
84 OPENSSL_secure_clear_free(ecx->privkey, privkeylen);
85 ecx->privkey = NULL;
86 return 0;
87 }
88 }
89
90
91 pubkey = ecx->pubkey;
92 if (param_pub_key != NULL
93 && !OSSL_PARAM_get_octet_string(param_pub_key,
94 (void **)&pubkey,
95 sizeof(ecx->pubkey), &pubkeylen))
96 return 0;
97
98 if ((param_pub_key != NULL && pubkeylen != ecx->keylen))
99 return 0;
100
101 if (param_pub_key == NULL && !ossl_ecx_public_from_private(ecx))
102 return 0;
103
104 ecx->haspubkey = 1;
105
106 return 1;
107 }
108
ossl_ecx_key_dup(const ECX_KEY * key,int selection)109 ECX_KEY *ossl_ecx_key_dup(const ECX_KEY *key, int selection)
110 {
111 ECX_KEY *ret = OPENSSL_zalloc(sizeof(*ret));
112
113 if (ret == NULL) {
114 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
115 return NULL;
116 }
117
118 ret->lock = CRYPTO_THREAD_lock_new();
119 if (ret->lock == NULL) {
120 OPENSSL_free(ret);
121 return NULL;
122 }
123
124 ret->libctx = key->libctx;
125 ret->haspubkey = key->haspubkey;
126 ret->keylen = key->keylen;
127 ret->type = key->type;
128 ret->references = 1;
129
130 if (key->propq != NULL) {
131 ret->propq = OPENSSL_strdup(key->propq);
132 if (ret->propq == NULL)
133 goto err;
134 }
135
136 if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
137 memcpy(ret->pubkey, key->pubkey, sizeof(ret->pubkey));
138
139 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0
140 && key->privkey != NULL) {
141 if (ossl_ecx_key_allocate_privkey(ret) == NULL)
142 goto err;
143 memcpy(ret->privkey, key->privkey, ret->keylen);
144 }
145
146 return ret;
147
148 err:
149 ossl_ecx_key_free(ret);
150 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
151 return NULL;
152 }
153
154 #ifndef FIPS_MODULE
ossl_ecx_key_op(const X509_ALGOR * palg,const unsigned char * p,int plen,int id,ecx_key_op_t op,OSSL_LIB_CTX * libctx,const char * propq)155 ECX_KEY *ossl_ecx_key_op(const X509_ALGOR *palg,
156 const unsigned char *p, int plen,
157 int id, ecx_key_op_t op,
158 OSSL_LIB_CTX *libctx, const char *propq)
159 {
160 ECX_KEY *key = NULL;
161 unsigned char *privkey, *pubkey;
162
163 if (op != KEY_OP_KEYGEN) {
164 if (palg != NULL) {
165 int ptype;
166
167 /* Algorithm parameters must be absent */
168 X509_ALGOR_get0(NULL, &ptype, NULL, palg);
169 if (ptype != V_ASN1_UNDEF) {
170 ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
171 return 0;
172 }
173 if (id == EVP_PKEY_NONE)
174 id = OBJ_obj2nid(palg->algorithm);
175 else if (id != OBJ_obj2nid(palg->algorithm)) {
176 ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
177 return 0;
178 }
179 }
180
181 if (p == NULL || id == EVP_PKEY_NONE || plen != KEYLENID(id)) {
182 ERR_raise(ERR_LIB_EC, EC_R_INVALID_ENCODING);
183 return 0;
184 }
185 }
186
187 key = ossl_ecx_key_new(libctx, KEYNID2TYPE(id), 1, propq);
188 if (key == NULL) {
189 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
190 return 0;
191 }
192 pubkey = key->pubkey;
193
194 if (op == KEY_OP_PUBLIC) {
195 memcpy(pubkey, p, plen);
196 } else {
197 privkey = ossl_ecx_key_allocate_privkey(key);
198 if (privkey == NULL) {
199 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
200 goto err;
201 }
202 if (op == KEY_OP_KEYGEN) {
203 if (id != EVP_PKEY_NONE) {
204 if (RAND_priv_bytes_ex(libctx, privkey, KEYLENID(id), 0) <= 0)
205 goto err;
206 if (id == EVP_PKEY_X25519) {
207 privkey[0] &= 248;
208 privkey[X25519_KEYLEN - 1] &= 127;
209 privkey[X25519_KEYLEN - 1] |= 64;
210 } else if (id == EVP_PKEY_X448) {
211 privkey[0] &= 252;
212 privkey[X448_KEYLEN - 1] |= 128;
213 }
214 }
215 } else {
216 memcpy(privkey, p, KEYLENID(id));
217 }
218 if (!ossl_ecx_public_from_private(key)) {
219 ERR_raise(ERR_LIB_EC, EC_R_FAILED_MAKING_PUBLIC_KEY);
220 goto err;
221 }
222 }
223
224 return key;
225 err:
226 ossl_ecx_key_free(key);
227 return NULL;
228 }
229
ossl_ecx_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO * p8inf,OSSL_LIB_CTX * libctx,const char * propq)230 ECX_KEY *ossl_ecx_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO *p8inf,
231 OSSL_LIB_CTX *libctx, const char *propq)
232 {
233 ECX_KEY *ecx = NULL;
234 const unsigned char *p;
235 int plen;
236 ASN1_OCTET_STRING *oct = NULL;
237 const X509_ALGOR *palg;
238
239 if (!PKCS8_pkey_get0(NULL, &p, &plen, &palg, p8inf))
240 return 0;
241
242 oct = d2i_ASN1_OCTET_STRING(NULL, &p, plen);
243 if (oct == NULL) {
244 p = NULL;
245 plen = 0;
246 } else {
247 p = ASN1_STRING_get0_data(oct);
248 plen = ASN1_STRING_length(oct);
249 }
250
251 /*
252 * EVP_PKEY_NONE means that ecx_key_op() has to figure out the key type
253 * on its own.
254 */
255 ecx = ossl_ecx_key_op(palg, p, plen, EVP_PKEY_NONE, KEY_OP_PRIVATE,
256 libctx, propq);
257 ASN1_OCTET_STRING_free(oct);
258 return ecx;
259 }
260 #endif
261