Line | Count | Source (jump to first uncovered line) |
1 | | /* |
2 | | * Copyright (c) 2018 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/rsa.h> |
9 | | #include <openssl/obj_mac.h> |
10 | | |
11 | | #include "fido.h" |
12 | | #include "fido/rs256.h" |
13 | | |
14 | | #if OPENSSL_VERSION_NUMBER < 0x10100000L |
15 | | static int |
16 | | RSA_bits(const RSA *r) |
17 | | { |
18 | | return (BN_num_bits(r->n)); |
19 | | } |
20 | | |
21 | | static int |
22 | | RSA_set0_key(RSA *r, BIGNUM *n, BIGNUM *e, BIGNUM *d) |
23 | | { |
24 | | r->n = n; |
25 | | r->e = e; |
26 | | r->d = d; |
27 | | |
28 | | return (1); |
29 | | } |
30 | | |
31 | | static void |
32 | | RSA_get0_key(const RSA *r, const BIGNUM **n, const BIGNUM **e, const BIGNUM **d) |
33 | | { |
34 | | *n = r->n; |
35 | | *e = r->e; |
36 | | *d = r->d; |
37 | | } |
38 | | #endif /* OPENSSL_VERSION_NUMBER < 0x10100000L */ |
39 | | |
40 | | static int |
41 | | decode_bignum(const cbor_item_t *item, void *ptr, size_t len) |
42 | 154 | { |
43 | 154 | if (cbor_isa_bytestring(item) == false || |
44 | 154 | cbor_bytestring_is_definite(item) == false || |
45 | 154 | cbor_bytestring_length(item) != len) { |
46 | 10 | fido_log_debug("%s: cbor type", __func__); |
47 | 10 | return (-1); |
48 | 10 | } |
49 | 144 | |
50 | 144 | memcpy(ptr, cbor_bytestring_handle(item), len); |
51 | 144 | |
52 | 144 | return (0); |
53 | 144 | } |
54 | | |
55 | | static int |
56 | | decode_rsa_pubkey(const cbor_item_t *key, const cbor_item_t *val, void *arg) |
57 | 342 | { |
58 | 342 | rs256_pk_t *k = arg; |
59 | 342 | |
60 | 342 | if (cbor_isa_negint(key) == false || |
61 | 342 | cbor_int_get_width(key) != CBOR_INT_8) |
62 | 182 | return (0); /* ignore */ |
63 | 160 | |
64 | 160 | switch (cbor_get_uint8(key)) { |
65 | 85 | case 0: /* modulus */ |
66 | 85 | return (decode_bignum(val, &k->n, sizeof(k->n))); |
67 | 69 | case 1: /* public exponent */ |
68 | 69 | return (decode_bignum(val, &k->e, sizeof(k->e))); |
69 | 6 | } |
70 | 6 | |
71 | 6 | return (0); /* ignore */ |
72 | 6 | } |
73 | | |
74 | | int |
75 | | rs256_pk_decode(const cbor_item_t *item, rs256_pk_t *k) |
76 | 91 | { |
77 | 91 | if (cbor_isa_map(item) == false || |
78 | 91 | cbor_map_is_definite(item) == false || |
79 | 91 | cbor_map_iter(item, k, decode_rsa_pubkey) < 0) { |
80 | 15 | fido_log_debug("%s: cbor type", __func__); |
81 | 15 | return (-1); |
82 | 15 | } |
83 | 76 | |
84 | 76 | return (0); |
85 | 76 | } |
86 | | |
87 | | rs256_pk_t * |
88 | | rs256_pk_new(void) |
89 | 979 | { |
90 | 979 | return (calloc(1, sizeof(rs256_pk_t))); |
91 | 979 | } |
92 | | |
93 | | void |
94 | | rs256_pk_free(rs256_pk_t **pkp) |
95 | 2.10k | { |
96 | 2.10k | rs256_pk_t *pk; |
97 | 2.10k | |
98 | 2.10k | if (pkp == NULL || (pk = *pkp) == NULL) |
99 | 2.10k | return; |
100 | 975 | |
101 | 975 | freezero(pk, sizeof(*pk)); |
102 | 975 | *pkp = NULL; |
103 | 975 | } |
104 | | |
105 | | int |
106 | | rs256_pk_from_ptr(rs256_pk_t *pk, const void *ptr, size_t len) |
107 | 507 | { |
108 | 507 | if (len < sizeof(*pk)) |
109 | 458 | return (FIDO_ERR_INVALID_ARGUMENT); |
110 | 49 | |
111 | 49 | memcpy(pk, ptr, sizeof(*pk)); |
112 | 49 | |
113 | 49 | return (FIDO_OK); |
114 | 49 | } |
115 | | |
116 | | EVP_PKEY * |
117 | | rs256_pk_to_EVP_PKEY(const rs256_pk_t *k) |
118 | 622 | { |
119 | 622 | RSA *rsa = NULL; |
120 | 622 | EVP_PKEY *pkey = NULL; |
121 | 622 | BIGNUM *n = NULL; |
122 | 622 | BIGNUM *e = NULL; |
123 | 622 | int ok = -1; |
124 | 622 | |
125 | 622 | if ((n = BN_new()) == NULL || (e = BN_new()) == NULL) |
126 | 622 | goto fail; |
127 | 593 | |
128 | 593 | if (BN_bin2bn(k->n, sizeof(k->n), n) == NULL || |
129 | 593 | BN_bin2bn(k->e, sizeof(k->e), e) == NULL) { |
130 | 16 | fido_log_debug("%s: BN_bin2bn", __func__); |
131 | 16 | goto fail; |
132 | 16 | } |
133 | 577 | |
134 | 577 | if ((rsa = RSA_new()) == NULL || RSA_set0_key(rsa, n, e, NULL) == 0) { |
135 | 6 | fido_log_debug("%s: RSA_set0_key", __func__); |
136 | 6 | goto fail; |
137 | 6 | } |
138 | 571 | |
139 | 571 | /* at this point, n and e belong to rsa */ |
140 | 571 | n = NULL; |
141 | 571 | e = NULL; |
142 | 571 | |
143 | 571 | if ((pkey = EVP_PKEY_new()) == NULL || |
144 | 571 | EVP_PKEY_assign_RSA(pkey, rsa) == 0) { |
145 | 21 | fido_log_debug("%s: EVP_PKEY_assign_RSA", __func__); |
146 | 21 | goto fail; |
147 | 21 | } |
148 | 550 | |
149 | 550 | rsa = NULL; /* at this point, rsa belongs to evp */ |
150 | 550 | |
151 | 550 | ok = 0; |
152 | 622 | fail: |
153 | 622 | if (n != NULL) |
154 | 622 | BN_free(n); |
155 | 622 | if (e != NULL) |
156 | 622 | BN_free(e); |
157 | 622 | if (rsa != NULL) |
158 | 622 | RSA_free(rsa); |
159 | 622 | if (ok < 0 && pkey != NULL) { |
160 | 9 | EVP_PKEY_free(pkey); |
161 | 9 | pkey = NULL; |
162 | 9 | } |
163 | 622 | |
164 | 622 | return (pkey); |
165 | 550 | } |
166 | | |
167 | | int |
168 | | rs256_pk_from_RSA(rs256_pk_t *pk, const RSA *rsa) |
169 | 468 | { |
170 | 468 | const BIGNUM *n = NULL; |
171 | 468 | const BIGNUM *e = NULL; |
172 | 468 | const BIGNUM *d = NULL; |
173 | 468 | int k; |
174 | 468 | |
175 | 468 | if (RSA_bits(rsa) != 2048) { |
176 | 436 | fido_log_debug("%s: invalid key length", __func__); |
177 | 436 | return (FIDO_ERR_INVALID_ARGUMENT); |
178 | 436 | } |
179 | 32 | |
180 | 32 | RSA_get0_key(rsa, &n, &e, &d); |
181 | 32 | |
182 | 32 | if (n == NULL || e == NULL) { |
183 | 0 | fido_log_debug("%s: RSA_get0_key", __func__); |
184 | 0 | return (FIDO_ERR_INTERNAL); |
185 | 0 | } |
186 | 32 | |
187 | 32 | if ((k = BN_num_bytes(n)) < 0 || (size_t)k > sizeof(pk->n) || |
188 | 32 | (k = BN_num_bytes(e)) < 0 || (size_t)k > sizeof(pk->e)) { |
189 | 0 | fido_log_debug("%s: invalid key", __func__); |
190 | 0 | return (FIDO_ERR_INTERNAL); |
191 | 0 | } |
192 | 32 | |
193 | 32 | if ((k = BN_bn2bin(n, pk->n)) < 0 || (size_t)k > sizeof(pk->n) || |
194 | 32 | (k = BN_bn2bin(e, pk->e)) < 0 || (size_t)k > sizeof(pk->e)) { |
195 | 3 | fido_log_debug("%s: BN_bn2bin", __func__); |
196 | 3 | return (FIDO_ERR_INTERNAL); |
197 | 3 | } |
198 | 29 | |
199 | 29 | return (FIDO_OK); |
200 | 29 | } |