1 | /* |
2 | * Copyright 2007-2018 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 <stdio.h> |
11 | #include "internal/cryptlib.h" |
12 | #include <openssl/evp.h> |
13 | #include "crypto/asn1.h" |
14 | #include "crypto/evp.h" |
15 | |
16 | /* |
17 | * HMAC "ASN1" method. This is just here to indicate the maximum HMAC output |
18 | * length and to free up an HMAC key. |
19 | */ |
20 | |
21 | static int hmac_size(const EVP_PKEY *pkey) |
22 | { |
23 | return EVP_MAX_MD_SIZE; |
24 | } |
25 | |
26 | static void hmac_key_free(EVP_PKEY *pkey) |
27 | { |
28 | ASN1_OCTET_STRING *os = EVP_PKEY_get0(pkey); |
29 | if (os) { |
30 | if (os->data) |
31 | OPENSSL_cleanse(os->data, os->length); |
32 | ASN1_OCTET_STRING_free(os); |
33 | } |
34 | } |
35 | |
36 | static int hmac_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2) |
37 | { |
38 | switch (op) { |
39 | case ASN1_PKEY_CTRL_DEFAULT_MD_NID: |
40 | *(int *)arg2 = NID_sha256; |
41 | return 1; |
42 | |
43 | default: |
44 | return -2; |
45 | } |
46 | } |
47 | |
48 | static int hmac_pkey_public_cmp(const EVP_PKEY *a, const EVP_PKEY *b) |
49 | { |
50 | return ASN1_OCTET_STRING_cmp(EVP_PKEY_get0(a), EVP_PKEY_get0(b)); |
51 | } |
52 | |
53 | static int hmac_set_priv_key(EVP_PKEY *pkey, const unsigned char *priv, |
54 | size_t len) |
55 | { |
56 | ASN1_OCTET_STRING *os; |
57 | |
58 | if (pkey->pkey.ptr != NULL) |
59 | return 0; |
60 | |
61 | os = ASN1_OCTET_STRING_new(); |
62 | if (os == NULL) |
63 | return 0; |
64 | |
65 | |
66 | if (!ASN1_OCTET_STRING_set(os, priv, len)) { |
67 | ASN1_OCTET_STRING_free(os); |
68 | return 0; |
69 | } |
70 | |
71 | pkey->pkey.ptr = os; |
72 | return 1; |
73 | } |
74 | |
75 | static int hmac_get_priv_key(const EVP_PKEY *pkey, unsigned char *priv, |
76 | size_t *len) |
77 | { |
78 | ASN1_OCTET_STRING *os = (ASN1_OCTET_STRING *)pkey->pkey.ptr; |
79 | |
80 | if (priv == NULL) { |
81 | *len = ASN1_STRING_length(os); |
82 | return 1; |
83 | } |
84 | |
85 | if (os == NULL || *len < (size_t)ASN1_STRING_length(os)) |
86 | return 0; |
87 | |
88 | *len = ASN1_STRING_length(os); |
89 | memcpy(priv, ASN1_STRING_get0_data(os), *len); |
90 | |
91 | return 1; |
92 | } |
93 | |
94 | const EVP_PKEY_ASN1_METHOD hmac_asn1_meth = { |
95 | EVP_PKEY_HMAC, |
96 | EVP_PKEY_HMAC, |
97 | 0, |
98 | |
99 | "HMAC" , |
100 | "OpenSSL HMAC method" , |
101 | |
102 | 0, 0, hmac_pkey_public_cmp, 0, |
103 | |
104 | 0, 0, 0, |
105 | |
106 | hmac_size, |
107 | 0, 0, |
108 | 0, 0, 0, 0, 0, 0, 0, |
109 | |
110 | hmac_key_free, |
111 | hmac_pkey_ctrl, |
112 | NULL, |
113 | NULL, |
114 | |
115 | NULL, |
116 | NULL, |
117 | NULL, |
118 | |
119 | NULL, |
120 | NULL, |
121 | NULL, |
122 | |
123 | hmac_set_priv_key, |
124 | NULL, |
125 | hmac_get_priv_key, |
126 | NULL, |
127 | }; |
128 | |