1/*
2 * Copyright 2018-2022 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 * CMAC low level APIs are deprecated for public use, but still ok for internal
12 * use.
13 */
14#include "internal/deprecated.h"
15
16#include <openssl/core_dispatch.h>
17#include <openssl/core_names.h>
18#include <openssl/params.h>
19#include <openssl/evp.h>
20#include <openssl/cmac.h>
21
22#include "prov/implementations.h"
23#include "prov/provider_ctx.h"
24#include "prov/provider_util.h"
25#include "prov/providercommon.h"
26
27/*
28 * Forward declaration of everything implemented here.  This is not strictly
29 * necessary for the compiler, but provides an assurance that the signatures
30 * of the functions in the dispatch table are correct.
31 */
32static OSSL_FUNC_mac_newctx_fn cmac_new;
33static OSSL_FUNC_mac_dupctx_fn cmac_dup;
34static OSSL_FUNC_mac_freectx_fn cmac_free;
35static OSSL_FUNC_mac_gettable_ctx_params_fn cmac_gettable_ctx_params;
36static OSSL_FUNC_mac_get_ctx_params_fn cmac_get_ctx_params;
37static OSSL_FUNC_mac_settable_ctx_params_fn cmac_settable_ctx_params;
38static OSSL_FUNC_mac_set_ctx_params_fn cmac_set_ctx_params;
39static OSSL_FUNC_mac_init_fn cmac_init;
40static OSSL_FUNC_mac_update_fn cmac_update;
41static OSSL_FUNC_mac_final_fn cmac_final;
42
43/* local CMAC data */
44
45struct cmac_data_st {
46    void *provctx;
47    CMAC_CTX *ctx;
48    PROV_CIPHER cipher;
49};
50
51static void *cmac_new(void *provctx)
52{
53    struct cmac_data_st *macctx;
54
55    if (!ossl_prov_is_running())
56        return NULL;
57
58    if ((macctx = OPENSSL_zalloc(sizeof(*macctx))) == NULL
59        || (macctx->ctx = CMAC_CTX_new()) == NULL) {
60        OPENSSL_free(macctx);
61        macctx = NULL;
62    } else {
63        macctx->provctx = provctx;
64    }
65
66    return macctx;
67}
68
69static void cmac_free(void *vmacctx)
70{
71    struct cmac_data_st *macctx = vmacctx;
72
73    if (macctx != NULL) {
74        CMAC_CTX_free(macctx->ctx);
75        ossl_prov_cipher_reset(&macctx->cipher);
76        OPENSSL_free(macctx);
77    }
78}
79
80static void *cmac_dup(void *vsrc)
81{
82    struct cmac_data_st *src = vsrc;
83    struct cmac_data_st *dst;
84
85    if (!ossl_prov_is_running())
86        return NULL;
87
88    dst = cmac_new(src->provctx);
89    if (dst == NULL)
90        return NULL;
91    if (!CMAC_CTX_copy(dst->ctx, src->ctx)
92        || !ossl_prov_cipher_copy(&dst->cipher, &src->cipher)) {
93        cmac_free(dst);
94        return NULL;
95    }
96    return dst;
97}
98
99static size_t cmac_size(void *vmacctx)
100{
101    struct cmac_data_st *macctx = vmacctx;
102    const EVP_CIPHER_CTX *cipherctx = CMAC_CTX_get0_cipher_ctx(macctx->ctx);
103
104    if (EVP_CIPHER_CTX_get0_cipher(cipherctx) == NULL)
105        return 0;
106
107    return EVP_CIPHER_CTX_get_block_size(cipherctx);
108}
109
110static int cmac_setkey(struct cmac_data_st *macctx,
111                       const unsigned char *key, size_t keylen)
112{
113    int rv = CMAC_Init(macctx->ctx, key, keylen,
114                       ossl_prov_cipher_cipher(&macctx->cipher),
115                       ossl_prov_cipher_engine(&macctx->cipher));
116    ossl_prov_cipher_reset(&macctx->cipher);
117    return rv;
118}
119
120static int cmac_init(void *vmacctx, const unsigned char *key,
121                     size_t keylen, const OSSL_PARAM params[])
122{
123    struct cmac_data_st *macctx = vmacctx;
124
125    if (!ossl_prov_is_running() || !cmac_set_ctx_params(macctx, params))
126        return 0;
127    if (key != NULL)
128        return cmac_setkey(macctx, key, keylen);
129    /* Reinitialize the CMAC context */
130    return CMAC_Init(macctx->ctx, NULL, 0, NULL, NULL);
131}
132
133static int cmac_update(void *vmacctx, const unsigned char *data,
134                       size_t datalen)
135{
136    struct cmac_data_st *macctx = vmacctx;
137
138    return CMAC_Update(macctx->ctx, data, datalen);
139}
140
141static int cmac_final(void *vmacctx, unsigned char *out, size_t *outl,
142                      size_t outsize)
143{
144    struct cmac_data_st *macctx = vmacctx;
145
146    if (!ossl_prov_is_running())
147        return 0;
148
149    return CMAC_Final(macctx->ctx, out, outl);
150}
151
152static const OSSL_PARAM known_gettable_ctx_params[] = {
153    OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
154    OSSL_PARAM_size_t(OSSL_MAC_PARAM_BLOCK_SIZE, NULL),
155    OSSL_PARAM_END
156};
157static const OSSL_PARAM *cmac_gettable_ctx_params(ossl_unused void *ctx,
158                                                  ossl_unused void *provctx)
159{
160    return known_gettable_ctx_params;
161}
162
163static int cmac_get_ctx_params(void *vmacctx, OSSL_PARAM params[])
164{
165    OSSL_PARAM *p;
166
167    if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL
168            && !OSSL_PARAM_set_size_t(p, cmac_size(vmacctx)))
169        return 0;
170
171    if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_BLOCK_SIZE)) != NULL
172            && !OSSL_PARAM_set_size_t(p, cmac_size(vmacctx)))
173        return 0;
174
175    return 1;
176}
177
178static const OSSL_PARAM known_settable_ctx_params[] = {
179    OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_CIPHER, NULL, 0),
180    OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_PROPERTIES, NULL, 0),
181    OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
182    OSSL_PARAM_END
183};
184static const OSSL_PARAM *cmac_settable_ctx_params(ossl_unused void *ctx,
185                                                  ossl_unused void *provctx)
186{
187    return known_settable_ctx_params;
188}
189
190/*
191 * ALL parameters should be set before init().
192 */
193static int cmac_set_ctx_params(void *vmacctx, const OSSL_PARAM params[])
194{
195    struct cmac_data_st *macctx = vmacctx;
196    OSSL_LIB_CTX *ctx = PROV_LIBCTX_OF(macctx->provctx);
197    const OSSL_PARAM *p;
198
199    if (params == NULL)
200        return 1;
201
202    if (!ossl_prov_cipher_load_from_params(&macctx->cipher, params, ctx))
203        return 0;
204
205    if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL) {
206        if (p->data_type != OSSL_PARAM_OCTET_STRING)
207            return 0;
208        return cmac_setkey(macctx, p->data, p->data_size);
209    }
210    return 1;
211}
212
213const OSSL_DISPATCH ossl_cmac_functions[] = {
214    { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))cmac_new },
215    { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))cmac_dup },
216    { OSSL_FUNC_MAC_FREECTX, (void (*)(void))cmac_free },
217    { OSSL_FUNC_MAC_INIT, (void (*)(void))cmac_init },
218    { OSSL_FUNC_MAC_UPDATE, (void (*)(void))cmac_update },
219    { OSSL_FUNC_MAC_FINAL, (void (*)(void))cmac_final },
220    { OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS,
221      (void (*)(void))cmac_gettable_ctx_params },
222    { OSSL_FUNC_MAC_GET_CTX_PARAMS, (void (*)(void))cmac_get_ctx_params },
223    { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,
224      (void (*)(void))cmac_settable_ctx_params },
225    { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))cmac_set_ctx_params },
226    { 0, NULL }
227};
228