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
18static void aes_siv_cleanup(void *vctx);
19
20static 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
59static 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
77static 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
85static 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
93static 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
103static 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
123static 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
133const PROV_CIPHER_HW_AES_SIV *ossl_prov_cipher_hw_aes_siv(size_t keybits)
134{
135    return &aes_siv_hw;
136}
137