1 /*
2 * Copyright 2019-2021 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 /*
11 * This file uses the low level AES functions (which are deprecated for
12 * non-internal use) in order to implement provider AES ciphers.
13 */
14 #include "internal/deprecated.h"
15
16 #include "cipher_aes_siv.h"
17
18 static void aes_siv_cleanup(void *vctx);
19
aes_siv_initkey(void * vctx,const unsigned char * key,size_t keylen)20 static int aes_siv_initkey(void *vctx, const unsigned char *key, size_t keylen)
21 {
22 PROV_AES_SIV_CTX *ctx = (PROV_AES_SIV_CTX *)vctx;
23 SIV128_CONTEXT *sctx = &ctx->siv;
24 size_t klen = keylen / 2;
25 OSSL_LIB_CTX *libctx = ctx->libctx;
26 const char *propq = NULL;
27
28 EVP_CIPHER_free(ctx->cbc);
29 EVP_CIPHER_free(ctx->ctr);
30 ctx->cbc = NULL;
31 ctx->ctr = NULL;
32
33 switch (klen) {
34 case 16:
35 ctx->cbc = EVP_CIPHER_fetch(libctx, "AES-128-CBC", propq);
36 ctx->ctr = EVP_CIPHER_fetch(libctx, "AES-128-CTR", propq);
37 break;
38 case 24:
39 ctx->cbc = EVP_CIPHER_fetch(libctx, "AES-192-CBC", propq);
40 ctx->ctr = EVP_CIPHER_fetch(libctx, "AES-192-CTR", propq);
41 break;
42 case 32:
43 ctx->cbc = EVP_CIPHER_fetch(libctx, "AES-256-CBC", propq);
44 ctx->ctr = EVP_CIPHER_fetch(libctx, "AES-256-CTR", propq);
45 break;
46 default:
47 break;
48 }
49 if (ctx->cbc == NULL || ctx->ctr == NULL)
50 return 0;
51 /*
52 * klen is the length of the underlying cipher, not the input key,
53 * which should be twice as long
54 */
55 return ossl_siv128_init(sctx, key, klen, ctx->cbc, ctx->ctr, libctx,
56 propq);
57 }
58
aes_siv_dupctx(void * in_vctx,void * out_vctx)59 static int aes_siv_dupctx(void *in_vctx, void *out_vctx)
60 {
61 PROV_AES_SIV_CTX *in = (PROV_AES_SIV_CTX *)in_vctx;
62 PROV_AES_SIV_CTX *out = (PROV_AES_SIV_CTX *)out_vctx;
63
64 *out = *in;
65 out->siv.cipher_ctx = NULL;
66 out->siv.mac_ctx_init = NULL;
67 out->siv.mac = NULL;
68 if (!ossl_siv128_copy_ctx(&out->siv, &in->siv))
69 return 0;
70 if (out->cbc != NULL)
71 EVP_CIPHER_up_ref(out->cbc);
72 if (out->ctr != NULL)
73 EVP_CIPHER_up_ref(out->ctr);
74 return 1;
75 }
76
aes_siv_settag(void * vctx,const unsigned char * tag,size_t tagl)77 static int aes_siv_settag(void *vctx, const unsigned char *tag, size_t tagl)
78 {
79 PROV_AES_SIV_CTX *ctx = (PROV_AES_SIV_CTX *)vctx;
80 SIV128_CONTEXT *sctx = &ctx->siv;
81
82 return ossl_siv128_set_tag(sctx, tag, tagl);
83 }
84
aes_siv_setspeed(void * vctx,int speed)85 static void aes_siv_setspeed(void *vctx, int speed)
86 {
87 PROV_AES_SIV_CTX *ctx = (PROV_AES_SIV_CTX *)vctx;
88 SIV128_CONTEXT *sctx = &ctx->siv;
89
90 ossl_siv128_speed(sctx, (int)speed);
91 }
92
aes_siv_cleanup(void * vctx)93 static void aes_siv_cleanup(void *vctx)
94 {
95 PROV_AES_SIV_CTX *ctx = (PROV_AES_SIV_CTX *)vctx;
96 SIV128_CONTEXT *sctx = &ctx->siv;
97
98 ossl_siv128_cleanup(sctx);
99 EVP_CIPHER_free(ctx->cbc);
100 EVP_CIPHER_free(ctx->ctr);
101 }
102
aes_siv_cipher(void * vctx,unsigned char * out,const unsigned char * in,size_t len)103 static int aes_siv_cipher(void *vctx, unsigned char *out,
104 const unsigned char *in, size_t len)
105 {
106 PROV_AES_SIV_CTX *ctx = (PROV_AES_SIV_CTX *)vctx;
107 SIV128_CONTEXT *sctx = &ctx->siv;
108
109 /* EncryptFinal or DecryptFinal */
110 if (in == NULL)
111 return ossl_siv128_finish(sctx) == 0;
112
113 /* Deal with associated data */
114 if (out == NULL)
115 return (ossl_siv128_aad(sctx, in, len) == 1);
116
117 if (ctx->enc)
118 return ossl_siv128_encrypt(sctx, in, out, len) > 0;
119
120 return ossl_siv128_decrypt(sctx, in, out, len) > 0;
121 }
122
123 static const PROV_CIPHER_HW_AES_SIV aes_siv_hw =
124 {
125 aes_siv_initkey,
126 aes_siv_cipher,
127 aes_siv_setspeed,
128 aes_siv_settag,
129 aes_siv_cleanup,
130 aes_siv_dupctx,
131 };
132
ossl_prov_cipher_hw_aes_siv(size_t keybits)133 const PROV_CIPHER_HW_AES_SIV *ossl_prov_cipher_hw_aes_siv(size_t keybits)
134 {
135 return &aes_siv_hw;
136 }
137