1 /*
2 * Copyright 2020-2023 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/err.h>
12 #include <openssl/proverr.h>
13 #include "crypto/ecx.h"
14 #include "internal/common.h" /* for ossl_assert() */
15
16 #ifdef S390X_EC_ASM
17 # include "s390x_arch.h"
18 #endif
19
ossl_ecx_key_new(OSSL_LIB_CTX * libctx,ECX_KEY_TYPE type,int haspubkey,const char * propq)20 ECX_KEY *ossl_ecx_key_new(OSSL_LIB_CTX *libctx, ECX_KEY_TYPE type, int haspubkey,
21 const char *propq)
22 {
23 ECX_KEY *ret = OPENSSL_zalloc(sizeof(*ret));
24
25 if (ret == NULL)
26 return NULL;
27
28 ret->libctx = libctx;
29 ret->haspubkey = haspubkey;
30 switch (type) {
31 case ECX_KEY_TYPE_X25519:
32 ret->keylen = X25519_KEYLEN;
33 break;
34 case ECX_KEY_TYPE_X448:
35 ret->keylen = X448_KEYLEN;
36 break;
37 case ECX_KEY_TYPE_ED25519:
38 ret->keylen = ED25519_KEYLEN;
39 break;
40 case ECX_KEY_TYPE_ED448:
41 ret->keylen = ED448_KEYLEN;
42 break;
43 }
44 ret->type = type;
45
46 if (!CRYPTO_NEW_REF(&ret->references, 1))
47 goto err;
48
49 if (propq != NULL) {
50 ret->propq = OPENSSL_strdup(propq);
51 if (ret->propq == NULL)
52 goto err;
53 }
54 return ret;
55 err:
56 if (ret != NULL) {
57 OPENSSL_free(ret->propq);
58 CRYPTO_FREE_REF(&ret->references);
59 }
60 OPENSSL_free(ret);
61 return NULL;
62 }
63
ossl_ecx_key_free(ECX_KEY * key)64 void ossl_ecx_key_free(ECX_KEY *key)
65 {
66 int i;
67
68 if (key == NULL)
69 return;
70
71 CRYPTO_DOWN_REF(&key->references, &i);
72 REF_PRINT_COUNT("ECX_KEY", i, key);
73 if (i > 0)
74 return;
75 REF_ASSERT_ISNT(i < 0);
76
77 OPENSSL_free(key->propq);
78 #ifdef OPENSSL_PEDANTIC_ZEROIZATION
79 OPENSSL_cleanse(&key->pubkey, sizeof(key->pubkey));
80 #endif
81 OPENSSL_secure_clear_free(key->privkey, key->keylen);
82 CRYPTO_FREE_REF(&key->references);
83 OPENSSL_free(key);
84 }
85
ossl_ecx_key_set0_libctx(ECX_KEY * key,OSSL_LIB_CTX * libctx)86 void ossl_ecx_key_set0_libctx(ECX_KEY *key, OSSL_LIB_CTX *libctx)
87 {
88 key->libctx = libctx;
89 }
90
ossl_ecx_key_up_ref(ECX_KEY * key)91 int ossl_ecx_key_up_ref(ECX_KEY *key)
92 {
93 int i;
94
95 if (CRYPTO_UP_REF(&key->references, &i) <= 0)
96 return 0;
97
98 REF_PRINT_COUNT("ECX_KEY", i, key);
99 REF_ASSERT_ISNT(i < 2);
100 return ((i > 1) ? 1 : 0);
101 }
102
ossl_ecx_key_allocate_privkey(ECX_KEY * key)103 unsigned char *ossl_ecx_key_allocate_privkey(ECX_KEY *key)
104 {
105 key->privkey = OPENSSL_secure_zalloc(key->keylen);
106
107 return key->privkey;
108 }
109
ossl_ecx_compute_key(ECX_KEY * peer,ECX_KEY * priv,size_t keylen,unsigned char * secret,size_t * secretlen,size_t outlen)110 int ossl_ecx_compute_key(ECX_KEY *peer, ECX_KEY *priv, size_t keylen,
111 unsigned char *secret, size_t *secretlen, size_t outlen)
112 {
113 if (priv == NULL
114 || priv->privkey == NULL
115 || peer == NULL) {
116 ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_KEY);
117 return 0;
118 }
119
120 if (!ossl_assert(keylen == X25519_KEYLEN
121 || keylen == X448_KEYLEN)) {
122 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
123 return 0;
124 }
125
126 if (secret == NULL) {
127 *secretlen = keylen;
128 return 1;
129 }
130 if (outlen < keylen) {
131 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
132 return 0;
133 }
134
135 if (keylen == X25519_KEYLEN) {
136 #ifdef S390X_EC_ASM
137 if (OPENSSL_s390xcap_P.pcc[1]
138 & S390X_CAPBIT(S390X_SCALAR_MULTIPLY_X25519)) {
139 if (s390x_x25519_mul(secret, peer->pubkey, priv->privkey) == 0) {
140 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_DURING_DERIVATION);
141 return 0;
142 }
143 } else
144 #endif
145 if (ossl_x25519(secret, priv->privkey, peer->pubkey) == 0) {
146 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_DURING_DERIVATION);
147 return 0;
148 }
149 } else {
150 #ifdef S390X_EC_ASM
151 if (OPENSSL_s390xcap_P.pcc[1]
152 & S390X_CAPBIT(S390X_SCALAR_MULTIPLY_X448)) {
153 if (s390x_x448_mul(secret, peer->pubkey, priv->privkey) == 0) {
154 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_DURING_DERIVATION);
155 return 0;
156 }
157 } else
158 #endif
159 if (ossl_x448(secret, priv->privkey, peer->pubkey) == 0) {
160 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_DURING_DERIVATION);
161 return 0;
162 }
163 }
164 *secretlen = keylen;
165 return 1;
166 }
167