1 /*
2  * Copyright 2018-2023 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 <stdlib.h>
11 #include <openssl/core_dispatch.h>
12 #include <openssl/core_names.h>
13 #include <openssl/params.h>
14 #include <openssl/evp.h>
15 #include <openssl/err.h>
16 #include <openssl/proverr.h>
17 
18 #include "prov/implementations.h"
19 #include "prov/provider_ctx.h"
20 #include "prov/provider_util.h"
21 #include "prov/providercommon.h"
22 
23 /*
24  * Forward declaration of everything implemented here.  This is not strictly
25  * necessary for the compiler, but provides an assurance that the signatures
26  * of the functions in the dispatch table are correct.
27  */
28 static OSSL_FUNC_mac_newctx_fn gmac_new;
29 static OSSL_FUNC_mac_dupctx_fn gmac_dup;
30 static OSSL_FUNC_mac_freectx_fn gmac_free;
31 static OSSL_FUNC_mac_gettable_params_fn gmac_gettable_params;
32 static OSSL_FUNC_mac_get_params_fn gmac_get_params;
33 static OSSL_FUNC_mac_settable_ctx_params_fn gmac_settable_ctx_params;
34 static OSSL_FUNC_mac_set_ctx_params_fn gmac_set_ctx_params;
35 static OSSL_FUNC_mac_init_fn gmac_init;
36 static OSSL_FUNC_mac_update_fn gmac_update;
37 static OSSL_FUNC_mac_final_fn gmac_final;
38 
39 /* local GMAC pkey structure */
40 
41 struct gmac_data_st {
42     void *provctx;
43     EVP_CIPHER_CTX *ctx;         /* Cipher context */
44     PROV_CIPHER cipher;
45 };
46 
gmac_free(void * vmacctx)47 static void gmac_free(void *vmacctx)
48 {
49     struct gmac_data_st *macctx = vmacctx;
50 
51     if (macctx != NULL) {
52         EVP_CIPHER_CTX_free(macctx->ctx);
53         ossl_prov_cipher_reset(&macctx->cipher);
54         OPENSSL_free(macctx);
55     }
56 }
57 
gmac_new(void * provctx)58 static void *gmac_new(void *provctx)
59 {
60     struct gmac_data_st *macctx;
61 
62     if (!ossl_prov_is_running())
63         return NULL;
64 
65     if ((macctx = OPENSSL_zalloc(sizeof(*macctx))) == NULL
66         || (macctx->ctx = EVP_CIPHER_CTX_new()) == NULL) {
67         gmac_free(macctx);
68         return NULL;
69     }
70     macctx->provctx = provctx;
71 
72     return macctx;
73 }
74 
gmac_dup(void * vsrc)75 static void *gmac_dup(void *vsrc)
76 {
77     struct gmac_data_st *src = vsrc;
78     struct gmac_data_st *dst;
79 
80     if (!ossl_prov_is_running())
81         return NULL;
82 
83     dst = gmac_new(src->provctx);
84     if (dst == NULL)
85         return NULL;
86 
87     if (!EVP_CIPHER_CTX_copy(dst->ctx, src->ctx)
88         || !ossl_prov_cipher_copy(&dst->cipher, &src->cipher)) {
89         gmac_free(dst);
90         return NULL;
91     }
92     return dst;
93 }
94 
gmac_size(void)95 static size_t gmac_size(void)
96 {
97     return EVP_GCM_TLS_TAG_LEN;
98 }
99 
gmac_setkey(struct gmac_data_st * macctx,const unsigned char * key,size_t keylen)100 static int gmac_setkey(struct gmac_data_st *macctx,
101                        const unsigned char *key, size_t keylen)
102 {
103     EVP_CIPHER_CTX *ctx = macctx->ctx;
104 
105     if (keylen != (size_t)EVP_CIPHER_CTX_get_key_length(ctx)) {
106         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
107         return 0;
108     }
109     if (!EVP_EncryptInit_ex(ctx, NULL, NULL, key, NULL))
110         return 0;
111     return 1;
112 }
113 
gmac_init(void * vmacctx,const unsigned char * key,size_t keylen,const OSSL_PARAM params[])114 static int gmac_init(void *vmacctx, const unsigned char *key,
115                      size_t keylen, const OSSL_PARAM params[])
116 {
117     struct gmac_data_st *macctx = vmacctx;
118 
119     if (!ossl_prov_is_running() || !gmac_set_ctx_params(macctx, params))
120         return 0;
121     if (key != NULL)
122         return gmac_setkey(macctx, key, keylen);
123     return EVP_EncryptInit_ex(macctx->ctx, NULL, NULL, NULL, NULL);
124 }
125 
gmac_update(void * vmacctx,const unsigned char * data,size_t datalen)126 static int gmac_update(void *vmacctx, const unsigned char *data,
127                        size_t datalen)
128 {
129     struct gmac_data_st *macctx = vmacctx;
130     EVP_CIPHER_CTX *ctx = macctx->ctx;
131     int outlen;
132 
133     if (datalen == 0)
134         return 1;
135 
136     while (datalen > INT_MAX) {
137         if (!EVP_EncryptUpdate(ctx, NULL, &outlen, data, INT_MAX))
138             return 0;
139         data += INT_MAX;
140         datalen -= INT_MAX;
141     }
142     return EVP_EncryptUpdate(ctx, NULL, &outlen, data, datalen);
143 }
144 
gmac_final(void * vmacctx,unsigned char * out,size_t * outl,size_t outsize)145 static int gmac_final(void *vmacctx, unsigned char *out, size_t *outl,
146                       size_t outsize)
147 {
148     OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
149     struct gmac_data_st *macctx = vmacctx;
150     int hlen = 0;
151 
152     if (!ossl_prov_is_running())
153         return 0;
154 
155     if (!EVP_EncryptFinal_ex(macctx->ctx, out, &hlen))
156         return 0;
157 
158     hlen = gmac_size();
159     params[0] = OSSL_PARAM_construct_octet_string(OSSL_CIPHER_PARAM_AEAD_TAG,
160                                                   out, (size_t)hlen);
161     if (!EVP_CIPHER_CTX_get_params(macctx->ctx, params))
162         return 0;
163 
164     *outl = hlen;
165     return 1;
166 }
167 
168 static const OSSL_PARAM known_gettable_params[] = {
169     OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL),
170     OSSL_PARAM_END
171 };
gmac_gettable_params(void * provctx)172 static const OSSL_PARAM *gmac_gettable_params(void *provctx)
173 {
174     return known_gettable_params;
175 }
176 
gmac_get_params(OSSL_PARAM params[])177 static int gmac_get_params(OSSL_PARAM params[])
178 {
179     OSSL_PARAM *p;
180 
181     if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL)
182         return OSSL_PARAM_set_size_t(p, gmac_size());
183 
184     return 1;
185 }
186 
187 static const OSSL_PARAM known_settable_ctx_params[] = {
188     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_CIPHER, NULL, 0),
189     OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_PROPERTIES, NULL, 0),
190     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0),
191     OSSL_PARAM_octet_string(OSSL_MAC_PARAM_IV, NULL, 0),
192     OSSL_PARAM_END
193 };
gmac_settable_ctx_params(ossl_unused void * ctx,ossl_unused void * provctx)194 static const OSSL_PARAM *gmac_settable_ctx_params(ossl_unused void *ctx,
195                                                   ossl_unused void *provctx)
196 {
197     return known_settable_ctx_params;
198 }
199 
200 /*
201  * ALL parameters should be set before init().
202  */
gmac_set_ctx_params(void * vmacctx,const OSSL_PARAM params[])203 static int gmac_set_ctx_params(void *vmacctx, const OSSL_PARAM params[])
204 {
205     struct gmac_data_st *macctx = vmacctx;
206     EVP_CIPHER_CTX *ctx = macctx->ctx;
207     OSSL_LIB_CTX *provctx = PROV_LIBCTX_OF(macctx->provctx);
208     const OSSL_PARAM *p;
209 
210     if (ossl_param_is_empty(params))
211         return 1;
212     if (ctx == NULL)
213         return 0;
214 
215     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_CIPHER)) != NULL) {
216         if (!ossl_prov_cipher_load_from_params(&macctx->cipher, params, provctx))
217             return 0;
218         if (EVP_CIPHER_get_mode(ossl_prov_cipher_cipher(&macctx->cipher))
219             != EVP_CIPH_GCM_MODE) {
220             ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_MODE);
221             return 0;
222         }
223         if (!EVP_EncryptInit_ex(ctx, ossl_prov_cipher_cipher(&macctx->cipher),
224                                 ossl_prov_cipher_engine(&macctx->cipher), NULL,
225                                 NULL))
226             return 0;
227     }
228 
229     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL)
230         if (p->data_type != OSSL_PARAM_OCTET_STRING
231                 || !gmac_setkey(macctx, p->data, p->data_size))
232             return 0;
233 
234     if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_IV)) != NULL) {
235         if (p->data_type != OSSL_PARAM_OCTET_STRING)
236             return 0;
237 
238         if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN,
239                                  p->data_size, NULL) <= 0
240             || !EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, p->data))
241             return 0;
242     }
243     return 1;
244 }
245 
246 const OSSL_DISPATCH ossl_gmac_functions[] = {
247     { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))gmac_new },
248     { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))gmac_dup },
249     { OSSL_FUNC_MAC_FREECTX, (void (*)(void))gmac_free },
250     { OSSL_FUNC_MAC_INIT, (void (*)(void))gmac_init },
251     { OSSL_FUNC_MAC_UPDATE, (void (*)(void))gmac_update },
252     { OSSL_FUNC_MAC_FINAL, (void (*)(void))gmac_final },
253     { OSSL_FUNC_MAC_GETTABLE_PARAMS, (void (*)(void))gmac_gettable_params },
254     { OSSL_FUNC_MAC_GET_PARAMS, (void (*)(void))gmac_get_params },
255     { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS,
256       (void (*)(void))gmac_settable_ctx_params },
257     { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))gmac_set_ctx_params },
258     OSSL_DISPATCH_END
259 };
260