Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * Copyright (c) 2019-2021 Yubico AB. All rights reserved. |
3 | | * Use of this source code is governed by a BSD-style |
4 | | * license that can be found in the LICENSE file. |
5 | | */ |
6 | | |
7 | | #include <openssl/bn.h> |
8 | | #include <openssl/obj_mac.h> |
9 | | |
10 | | #include "fido.h" |
11 | | #include "fido/eddsa.h" |
12 | | |
13 | | #if defined(LIBRESSL_VERSION_NUMBER) |
14 | | EVP_PKEY * |
15 | | EVP_PKEY_new_raw_public_key(int type, ENGINE *e, const unsigned char *key, |
16 | | size_t keylen) |
17 | | { |
18 | | (void)type; |
19 | | (void)e; |
20 | | (void)key; |
21 | | (void)keylen; |
22 | | |
23 | | fido_log_debug("%s: unimplemented", __func__); |
24 | | |
25 | | return (NULL); |
26 | | } |
27 | | |
28 | | int |
29 | | EVP_PKEY_get_raw_public_key(const EVP_PKEY *pkey, unsigned char *pub, |
30 | | size_t *len) |
31 | | { |
32 | | (void)pkey; |
33 | | (void)pub; |
34 | | (void)len; |
35 | | |
36 | | fido_log_debug("%s: unimplemented", __func__); |
37 | | |
38 | | return (0); |
39 | | } |
40 | | #endif /* LIBRESSL_VERSION_NUMBER */ |
41 | | |
42 | | #if defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x3040000f |
43 | | int |
44 | | EVP_DigestVerify(EVP_MD_CTX *ctx, const unsigned char *sigret, size_t siglen, |
45 | | const unsigned char *tbs, size_t tbslen) |
46 | | { |
47 | | (void)ctx; |
48 | | (void)sigret; |
49 | | (void)siglen; |
50 | | (void)tbs; |
51 | | (void)tbslen; |
52 | | |
53 | | fido_log_debug("%s: unimplemented", __func__); |
54 | | |
55 | | return (0); |
56 | | } |
57 | | #endif /* LIBRESSL_VERSION_NUMBER < 0x3040000f */ |
58 | | |
59 | | static int |
60 | | decode_coord(const cbor_item_t *item, void *xy, size_t xy_len) |
61 | 218 | { |
62 | 218 | if (cbor_isa_bytestring(item) == false || |
63 | 218 | cbor_bytestring_is_definite(item) == false || |
64 | 218 | cbor_bytestring_length(item) != xy_len) { |
65 | 5 | fido_log_debug("%s: cbor type", __func__); |
66 | 5 | return (-1); |
67 | 5 | } |
68 | | |
69 | 213 | memcpy(xy, cbor_bytestring_handle(item), xy_len); |
70 | | |
71 | 213 | return (0); |
72 | 213 | } |
73 | | |
74 | | static int |
75 | | decode_pubkey_point(const cbor_item_t *key, const cbor_item_t *val, void *arg) |
76 | 945 | { |
77 | 945 | eddsa_pk_t *k = arg; |
78 | | |
79 | 945 | if (cbor_isa_negint(key) == false || |
80 | 945 | cbor_int_get_width(key) != CBOR_INT_8) |
81 | 486 | return (0); /* ignore */ |
82 | | |
83 | 459 | switch (cbor_get_uint8(key)) { |
84 | 218 | case 1: /* x coordinate */ |
85 | 218 | return (decode_coord(val, &k->x, sizeof(k->x))); |
86 | 241 | } |
87 | | |
88 | 241 | return (0); /* ignore */ |
89 | 241 | } |
90 | | |
91 | | int |
92 | | eddsa_pk_decode(const cbor_item_t *item, eddsa_pk_t *k) |
93 | 241 | { |
94 | 241 | if (cbor_isa_map(item) == false || |
95 | 241 | cbor_map_is_definite(item) == false || |
96 | 241 | cbor_map_iter(item, k, decode_pubkey_point) < 0) { |
97 | 9 | fido_log_debug("%s: cbor type", __func__); |
98 | 9 | return (-1); |
99 | 9 | } |
100 | | |
101 | 232 | return (0); |
102 | 232 | } |
103 | | |
104 | | eddsa_pk_t * |
105 | | eddsa_pk_new(void) |
106 | 2.76k | { |
107 | 2.76k | return (calloc(1, sizeof(eddsa_pk_t))); |
108 | 2.76k | } |
109 | | |
110 | | void |
111 | | eddsa_pk_free(eddsa_pk_t **pkp) |
112 | 3.72k | { |
113 | 3.72k | eddsa_pk_t *pk; |
114 | | |
115 | 3.72k | if (pkp == NULL || (pk = *pkp) == NULL) |
116 | 3.72k | return; |
117 | | |
118 | 2.75k | freezero(pk, sizeof(*pk)); |
119 | 2.75k | *pkp = NULL; |
120 | 2.75k | } |
121 | | |
122 | | int |
123 | | eddsa_pk_from_ptr(eddsa_pk_t *pk, const void *ptr, size_t len) |
124 | 1.38k | { |
125 | 1.38k | if (len < sizeof(*pk)) |
126 | 1.36k | return (FIDO_ERR_INVALID_ARGUMENT); |
127 | | |
128 | 16 | memcpy(pk, ptr, sizeof(*pk)); |
129 | | |
130 | 16 | return (FIDO_OK); |
131 | 16 | } |
132 | | |
133 | | EVP_PKEY * |
134 | | eddsa_pk_to_EVP_PKEY(const eddsa_pk_t *k) |
135 | 1.48k | { |
136 | 1.48k | EVP_PKEY *pkey = NULL; |
137 | | |
138 | 1.48k | if ((pkey = EVP_PKEY_new_raw_public_key(EVP_PKEY_ED25519, NULL, k->x, |
139 | 1.48k | sizeof(k->x))) == NULL) |
140 | 1.48k | fido_log_debug("%s: EVP_PKEY_new_raw_public_key", __func__); |
141 | | |
142 | 1.48k | return (pkey); |
143 | 1.48k | } |
144 | | |
145 | | int |
146 | | eddsa_pk_from_EVP_PKEY(eddsa_pk_t *pk, const EVP_PKEY *pkey) |
147 | 1.36k | { |
148 | 1.36k | size_t len = 0; |
149 | | |
150 | 1.36k | if (EVP_PKEY_get_raw_public_key(pkey, NULL, &len) != 1 || |
151 | 1.36k | len != sizeof(pk->x)) |
152 | 6 | return (FIDO_ERR_INTERNAL); |
153 | 1.36k | if (EVP_PKEY_get_raw_public_key(pkey, pk->x, &len) != 1 || |
154 | 1.36k | len != sizeof(pk->x)) |
155 | 6 | return (FIDO_ERR_INTERNAL); |
156 | | |
157 | 1.35k | return (FIDO_OK); |
158 | 1.35k | } |
159 | | |
160 | | int |
161 | | eddsa_verify_sig(const fido_blob_t *dgst, EVP_PKEY *pkey, |
162 | | const fido_blob_t *sig) |
163 | 94 | { |
164 | 94 | EVP_MD_CTX *mdctx = NULL; |
165 | 94 | int ok = -1; |
166 | | |
167 | 94 | if (EVP_PKEY_base_id(pkey) != EVP_PKEY_ED25519) { |
168 | 1 | fido_log_debug("%s: EVP_PKEY_base_id", __func__); |
169 | 1 | goto fail; |
170 | 1 | } |
171 | | |
172 | | /* EVP_DigestVerify needs ints */ |
173 | 93 | if (dgst->len > INT_MAX || sig->len > INT_MAX) { |
174 | 0 | fido_log_debug("%s: dgst->len=%zu, sig->len=%zu", __func__, |
175 | 0 | dgst->len, sig->len); |
176 | 0 | return (-1); |
177 | 0 | } |
178 | | |
179 | 93 | if ((mdctx = EVP_MD_CTX_new()) == NULL) { |
180 | 4 | fido_log_debug("%s: EVP_MD_CTX_new", __func__); |
181 | 4 | goto fail; |
182 | 4 | } |
183 | | |
184 | 89 | if (EVP_DigestVerifyInit(mdctx, NULL, NULL, NULL, pkey) != 1) { |
185 | 4 | fido_log_debug("%s: EVP_DigestVerifyInit", __func__); |
186 | 4 | goto fail; |
187 | 4 | } |
188 | | |
189 | 85 | if (EVP_DigestVerify(mdctx, sig->ptr, sig->len, dgst->ptr, |
190 | 85 | dgst->len) != 1) { |
191 | 85 | fido_log_debug("%s: EVP_DigestVerify", __func__); |
192 | 85 | goto fail; |
193 | 85 | } |
194 | | |
195 | 0 | ok = 0; |
196 | 94 | fail: |
197 | 94 | EVP_MD_CTX_free(mdctx); |
198 | | |
199 | 94 | return (ok); |
200 | 0 | } |
201 | | |
202 | | int |
203 | | eddsa_pk_verify_sig(const fido_blob_t *dgst, const eddsa_pk_t *pk, |
204 | | const fido_blob_t *sig) |
205 | 97 | { |
206 | 97 | EVP_PKEY *pkey; |
207 | 97 | int ok = -1; |
208 | | |
209 | 97 | if ((pkey = eddsa_pk_to_EVP_PKEY(pk)) == NULL || |
210 | 97 | eddsa_verify_sig(dgst, pkey, sig) < 0) { |
211 | 97 | fido_log_debug("%s: eddsa_verify_sig", __func__); |
212 | 97 | goto fail; |
213 | 97 | } |
214 | | |
215 | 0 | ok = 0; |
216 | 97 | fail: |
217 | 97 | EVP_PKEY_free(pkey); |
218 | | |
219 | 97 | return (ok); |
220 | 0 | } |