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/* Dispatch functions for chacha20 cipher */
11
12#include <openssl/proverr.h>
13#include "cipher_chacha20.h"
14#include "prov/implementations.h"
15#include "prov/providercommon.h"
16
17#define CHACHA20_KEYLEN (CHACHA_KEY_SIZE)
18#define CHACHA20_BLKLEN (1)
19#define CHACHA20_IVLEN (CHACHA_CTR_SIZE)
20#define CHACHA20_FLAGS (PROV_CIPHER_FLAG_CUSTOM_IV)
21
22static OSSL_FUNC_cipher_newctx_fn chacha20_newctx;
23static OSSL_FUNC_cipher_freectx_fn chacha20_freectx;
24static OSSL_FUNC_cipher_get_params_fn chacha20_get_params;
25static OSSL_FUNC_cipher_get_ctx_params_fn chacha20_get_ctx_params;
26static OSSL_FUNC_cipher_set_ctx_params_fn chacha20_set_ctx_params;
27static OSSL_FUNC_cipher_gettable_ctx_params_fn chacha20_gettable_ctx_params;
28static OSSL_FUNC_cipher_settable_ctx_params_fn chacha20_settable_ctx_params;
29#define chacha20_cipher ossl_cipher_generic_cipher
30#define chacha20_update ossl_cipher_generic_stream_update
31#define chacha20_final ossl_cipher_generic_stream_final
32#define chacha20_gettable_params ossl_cipher_generic_gettable_params
33
34void ossl_chacha20_initctx(PROV_CHACHA20_CTX *ctx)
35{
36    ossl_cipher_generic_initkey(ctx, CHACHA20_KEYLEN * 8,
37                                CHACHA20_BLKLEN * 8,
38                                CHACHA20_IVLEN * 8,
39                                0, CHACHA20_FLAGS,
40                                ossl_prov_cipher_hw_chacha20(CHACHA20_KEYLEN * 8),
41                                NULL);
42}
43
44static void *chacha20_newctx(void *provctx)
45{
46    PROV_CHACHA20_CTX *ctx;
47
48    if (!ossl_prov_is_running())
49        return NULL;
50
51    ctx = OPENSSL_zalloc(sizeof(*ctx));
52    if (ctx != NULL)
53        ossl_chacha20_initctx(ctx);
54    return ctx;
55}
56
57static void chacha20_freectx(void *vctx)
58{
59    PROV_CHACHA20_CTX *ctx = (PROV_CHACHA20_CTX *)vctx;
60
61    if (ctx != NULL) {
62        ossl_cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx);
63        OPENSSL_clear_free(ctx, sizeof(*ctx));
64    }
65}
66
67static int chacha20_get_params(OSSL_PARAM params[])
68{
69    return ossl_cipher_generic_get_params(params, 0, CHACHA20_FLAGS,
70                                          CHACHA20_KEYLEN * 8,
71                                          CHACHA20_BLKLEN * 8,
72                                          CHACHA20_IVLEN * 8);
73}
74
75static int chacha20_get_ctx_params(void *vctx, OSSL_PARAM params[])
76{
77    OSSL_PARAM *p;
78
79    p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_IVLEN);
80    if (p != NULL && !OSSL_PARAM_set_size_t(p, CHACHA20_IVLEN)) {
81        ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER);
82        return 0;
83    }
84    p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_KEYLEN);
85    if (p != NULL && !OSSL_PARAM_set_size_t(p, CHACHA20_KEYLEN)) {
86        ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER);
87        return 0;
88    }
89
90    return 1;
91}
92
93static const OSSL_PARAM chacha20_known_gettable_ctx_params[] = {
94    OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_KEYLEN, NULL),
95    OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_IVLEN, NULL),
96    OSSL_PARAM_END
97};
98const OSSL_PARAM *chacha20_gettable_ctx_params(ossl_unused void *cctx,
99                                               ossl_unused void *provctx)
100{
101    return chacha20_known_gettable_ctx_params;
102}
103
104static int chacha20_set_ctx_params(void *vctx, const OSSL_PARAM params[])
105{
106    const OSSL_PARAM *p;
107    size_t len;
108
109    if (params == NULL)
110        return 1;
111
112    p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN);
113    if (p != NULL) {
114        if (!OSSL_PARAM_get_size_t(p, &len)) {
115            ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
116            return 0;
117        }
118        if (len != CHACHA20_KEYLEN) {
119            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
120            return 0;
121        }
122    }
123    p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_IVLEN);
124    if (p != NULL) {
125        if (!OSSL_PARAM_get_size_t(p, &len)) {
126            ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
127            return 0;
128        }
129        if (len != CHACHA20_IVLEN) {
130            ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH);
131            return 0;
132        }
133    }
134    return 1;
135}
136
137static const OSSL_PARAM chacha20_known_settable_ctx_params[] = {
138    OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_KEYLEN, NULL),
139    OSSL_PARAM_size_t(OSSL_CIPHER_PARAM_IVLEN, NULL),
140    OSSL_PARAM_END
141};
142const OSSL_PARAM *chacha20_settable_ctx_params(ossl_unused void *cctx,
143                                               ossl_unused void *provctx)
144{
145    return chacha20_known_settable_ctx_params;
146}
147
148int ossl_chacha20_einit(void *vctx, const unsigned char *key, size_t keylen,
149                        const unsigned char *iv, size_t ivlen,
150                        const OSSL_PARAM params[])
151{
152    int ret;
153
154    /* The generic function checks for ossl_prov_is_running() */
155    ret = ossl_cipher_generic_einit(vctx, key, keylen, iv, ivlen, NULL);
156    if (ret && iv != NULL) {
157        PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
158        PROV_CIPHER_HW_CHACHA20 *hw = (PROV_CIPHER_HW_CHACHA20 *)ctx->hw;
159
160        hw->initiv(ctx);
161    }
162    if (ret && !chacha20_set_ctx_params(vctx, params))
163        ret = 0;
164    return ret;
165}
166
167int ossl_chacha20_dinit(void *vctx, const unsigned char *key, size_t keylen,
168                        const unsigned char *iv, size_t ivlen,
169                        const OSSL_PARAM params[])
170{
171    int ret;
172
173    /* The generic function checks for ossl_prov_is_running() */
174    ret = ossl_cipher_generic_dinit(vctx, key, keylen, iv, ivlen, NULL);
175    if (ret && iv != NULL) {
176        PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
177        PROV_CIPHER_HW_CHACHA20 *hw = (PROV_CIPHER_HW_CHACHA20 *)ctx->hw;
178
179        hw->initiv(ctx);
180    }
181    if (ret && !chacha20_set_ctx_params(vctx, params))
182        ret = 0;
183    return ret;
184}
185
186/* ossl_chacha20_functions */
187const OSSL_DISPATCH ossl_chacha20_functions[] = {
188    { OSSL_FUNC_CIPHER_NEWCTX, (void (*)(void))chacha20_newctx },
189    { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))chacha20_freectx },
190    { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))ossl_chacha20_einit },
191    { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))ossl_chacha20_dinit },
192    { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))chacha20_update },
193    { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))chacha20_final },
194    { OSSL_FUNC_CIPHER_CIPHER, (void (*)(void))chacha20_cipher},
195    { OSSL_FUNC_CIPHER_GET_PARAMS, (void (*)(void))chacha20_get_params },
196    { OSSL_FUNC_CIPHER_GETTABLE_PARAMS,(void (*)(void))chacha20_gettable_params },
197    { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, (void (*)(void))chacha20_get_ctx_params },
198    { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS,
199        (void (*)(void))chacha20_gettable_ctx_params },
200    { OSSL_FUNC_CIPHER_SET_CTX_PARAMS, (void (*)(void))chacha20_set_ctx_params },
201    { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS,
202        (void (*)(void))chacha20_settable_ctx_params },
203    { 0, NULL }
204};
205
206