1 /* 2 * Copyright 2018-2025 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 * HMAC low level APIs are deprecated for public use, but still ok for internal 12 * use. 13 */ 14 #include "internal/deprecated.h" 15 16 #include <string.h> 17 18 #include <openssl/core_dispatch.h> 19 #include <openssl/core_names.h> 20 #include <openssl/params.h> 21 #include <openssl/evp.h> 22 #include <openssl/hmac.h> 23 #include <openssl/proverr.h> 24 #include <openssl/err.h> 25 26 #include "internal/ssl3_cbc.h" 27 28 #include "prov/implementations.h" 29 #include "prov/provider_ctx.h" 30 #include "prov/provider_util.h" 31 #include "prov/providercommon.h" 32 #include "prov/securitycheck.h" 33 34 /* 35 * Forward declaration of everything implemented here. This is not strictly 36 * necessary for the compiler, but provides an assurance that the signatures 37 * of the functions in the dispatch table are correct. 38 */ 39 static OSSL_FUNC_mac_newctx_fn hmac_new; 40 static OSSL_FUNC_mac_dupctx_fn hmac_dup; 41 static OSSL_FUNC_mac_freectx_fn hmac_free; 42 static OSSL_FUNC_mac_gettable_ctx_params_fn hmac_gettable_ctx_params; 43 static OSSL_FUNC_mac_get_ctx_params_fn hmac_get_ctx_params; 44 static OSSL_FUNC_mac_settable_ctx_params_fn hmac_settable_ctx_params; 45 static OSSL_FUNC_mac_set_ctx_params_fn hmac_set_ctx_params; 46 static OSSL_FUNC_mac_init_fn hmac_init; 47 static OSSL_FUNC_mac_update_fn hmac_update; 48 static OSSL_FUNC_mac_final_fn hmac_final; 49 50 /* local HMAC context structure */ 51 52 /* typedef EVP_MAC_IMPL */ 53 struct hmac_data_st { 54 void *provctx; 55 HMAC_CTX *ctx; /* HMAC context */ 56 PROV_DIGEST digest; 57 unsigned char *key; 58 size_t keylen; 59 /* Length of full TLS record including the MAC and any padding */ 60 size_t tls_data_size; 61 unsigned char tls_header[13]; 62 int tls_header_set; 63 unsigned char tls_mac_out[EVP_MAX_MD_SIZE]; 64 size_t tls_mac_out_size; 65 #ifdef FIPS_MODULE 66 /* 67 * 'internal' is set to 1 if HMAC is used inside another algorithm such as a 68 * KDF. In this case it is the parent algorithm that is responsible for 69 * performing any conditional FIPS indicator related checks for the HMAC. 70 */ 71 int internal; 72 #endif 73 OSSL_FIPS_IND_DECLARE 74 }; 75 76 static void *hmac_new(void *provctx) 77 { 78 struct hmac_data_st *macctx; 79 80 if (!ossl_prov_is_running()) 81 return NULL; 82 83 if ((macctx = OPENSSL_zalloc(sizeof(*macctx))) == NULL 84 || (macctx->ctx = HMAC_CTX_new()) == NULL) { 85 OPENSSL_free(macctx); 86 return NULL; 87 } 88 macctx->provctx = provctx; 89 OSSL_FIPS_IND_INIT(macctx) 90 91 return macctx; 92 } 93 94 static void hmac_free(void *vmacctx) 95 { 96 struct hmac_data_st *macctx = vmacctx; 97 98 if (macctx != NULL) { 99 HMAC_CTX_free(macctx->ctx); 100 ossl_prov_digest_reset(&macctx->digest); 101 OPENSSL_clear_free(macctx->key, macctx->keylen); 102 OPENSSL_free(macctx); 103 } 104 } 105 106 static void *hmac_dup(void *vsrc) 107 { 108 struct hmac_data_st *src = vsrc; 109 struct hmac_data_st *dst; 110 HMAC_CTX *ctx; 111 112 if (!ossl_prov_is_running()) 113 return NULL; 114 dst = hmac_new(src->provctx); 115 if (dst == NULL) 116 return NULL; 117 118 ctx = dst->ctx; 119 *dst = *src; 120 dst->ctx = ctx; 121 dst->key = NULL; 122 memset(&dst->digest, 0, sizeof(dst->digest)); 123 124 if (!HMAC_CTX_copy(dst->ctx, src->ctx) 125 || !ossl_prov_digest_copy(&dst->digest, &src->digest)) { 126 hmac_free(dst); 127 return NULL; 128 } 129 if (src->key != NULL) { 130 dst->key = OPENSSL_malloc(src->keylen > 0 ? src->keylen : 1); 131 if (dst->key == NULL) { 132 hmac_free(dst); 133 return 0; 134 } 135 if (src->keylen > 0) 136 memcpy(dst->key, src->key, src->keylen); 137 } 138 return dst; 139 } 140 141 static size_t hmac_size(struct hmac_data_st *macctx) 142 { 143 return HMAC_size(macctx->ctx); 144 } 145 146 static int hmac_block_size(struct hmac_data_st *macctx) 147 { 148 const EVP_MD *md = ossl_prov_digest_md(&macctx->digest); 149 150 if (md == NULL) 151 return 0; 152 return EVP_MD_block_size(md); 153 } 154 155 static int hmac_setkey(struct hmac_data_st *macctx, 156 const unsigned char *key, size_t keylen) 157 { 158 const EVP_MD *digest; 159 160 #ifdef FIPS_MODULE 161 /* 162 * KDF's pass a salt rather than a key, 163 * which is why it skips the key check unless "HMAC" is fetched directly. 164 */ 165 if (!macctx->internal) { 166 OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(macctx->provctx); 167 int approved = ossl_mac_check_key_size(keylen); 168 169 if (!approved) { 170 if (!OSSL_FIPS_IND_ON_UNAPPROVED(macctx, OSSL_FIPS_IND_SETTABLE0, 171 libctx, "HMAC", "keysize", 172 ossl_fips_config_hmac_key_check)) { 173 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); 174 return 0; 175 } 176 } 177 } 178 #endif 179 180 if (macctx->key != NULL) 181 OPENSSL_clear_free(macctx->key, macctx->keylen); 182 /* Keep a copy of the key in case we need it for TLS HMAC */ 183 macctx->key = OPENSSL_malloc(keylen > 0 ? keylen : 1); 184 if (macctx->key == NULL) 185 return 0; 186 187 if (keylen > 0) 188 memcpy(macctx->key, key, keylen); 189 macctx->keylen = keylen; 190 191 digest = ossl_prov_digest_md(&macctx->digest); 192 /* HMAC_Init_ex doesn't tolerate all zero params, so we must be careful */ 193 if (key != NULL || (macctx->tls_data_size == 0 && digest != NULL)) 194 return HMAC_Init_ex(macctx->ctx, key, keylen, digest, 195 ossl_prov_digest_engine(&macctx->digest)); 196 return 1; 197 } 198 199 static int hmac_init(void *vmacctx, const unsigned char *key, 200 size_t keylen, const OSSL_PARAM params[]) 201 { 202 struct hmac_data_st *macctx = vmacctx; 203 204 if (!ossl_prov_is_running() || !hmac_set_ctx_params(macctx, params)) 205 return 0; 206 207 if (key != NULL) 208 return hmac_setkey(macctx, key, keylen); 209 210 /* Just reinit the HMAC context */ 211 return HMAC_Init_ex(macctx->ctx, NULL, 0, NULL, NULL); 212 } 213 214 static int hmac_update(void *vmacctx, const unsigned char *data, 215 size_t datalen) 216 { 217 struct hmac_data_st *macctx = vmacctx; 218 219 if (macctx->tls_data_size > 0) { 220 /* We're doing a TLS HMAC */ 221 if (!macctx->tls_header_set) { 222 /* We expect the first update call to contain the TLS header */ 223 if (datalen != sizeof(macctx->tls_header)) 224 return 0; 225 memcpy(macctx->tls_header, data, datalen); 226 macctx->tls_header_set = 1; 227 return 1; 228 } 229 /* macctx->tls_data_size is datalen plus the padding length */ 230 if (macctx->tls_data_size < datalen) 231 return 0; 232 233 return ssl3_cbc_digest_record(ossl_prov_digest_md(&macctx->digest), 234 macctx->tls_mac_out, 235 &macctx->tls_mac_out_size, 236 macctx->tls_header, 237 data, 238 datalen, 239 macctx->tls_data_size, 240 macctx->key, 241 macctx->keylen, 242 0); 243 } 244 245 return HMAC_Update(macctx->ctx, data, datalen); 246 } 247 248 static int hmac_final(void *vmacctx, unsigned char *out, size_t *outl, 249 size_t outsize) 250 { 251 unsigned int hlen; 252 struct hmac_data_st *macctx = vmacctx; 253 254 if (!ossl_prov_is_running()) 255 return 0; 256 if (macctx->tls_data_size > 0) { 257 if (macctx->tls_mac_out_size == 0) 258 return 0; 259 if (outl != NULL) 260 *outl = macctx->tls_mac_out_size; 261 memcpy(out, macctx->tls_mac_out, macctx->tls_mac_out_size); 262 return 1; 263 } 264 if (!HMAC_Final(macctx->ctx, out, &hlen)) 265 return 0; 266 *outl = hlen; 267 return 1; 268 } 269 270 static const OSSL_PARAM known_gettable_ctx_params[] = { 271 OSSL_PARAM_size_t(OSSL_MAC_PARAM_SIZE, NULL), 272 OSSL_PARAM_size_t(OSSL_MAC_PARAM_BLOCK_SIZE, NULL), 273 OSSL_FIPS_IND_GETTABLE_CTX_PARAM() 274 OSSL_PARAM_END 275 }; 276 static const OSSL_PARAM *hmac_gettable_ctx_params(ossl_unused void *ctx, 277 ossl_unused void *provctx) 278 { 279 return known_gettable_ctx_params; 280 } 281 282 static int hmac_get_ctx_params(void *vmacctx, OSSL_PARAM params[]) 283 { 284 struct hmac_data_st *macctx = vmacctx; 285 OSSL_PARAM *p; 286 287 if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_SIZE)) != NULL 288 && !OSSL_PARAM_set_size_t(p, hmac_size(macctx))) 289 return 0; 290 291 if ((p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_BLOCK_SIZE)) != NULL 292 && !OSSL_PARAM_set_int(p, hmac_block_size(macctx))) 293 return 0; 294 295 #ifdef FIPS_MODULE 296 p = OSSL_PARAM_locate(params, OSSL_MAC_PARAM_FIPS_APPROVED_INDICATOR); 297 if (p != NULL) { 298 int approved = 0; 299 300 if (!macctx->internal) 301 approved = OSSL_FIPS_IND_GET(macctx)->approved; 302 if (!OSSL_PARAM_set_int(p, approved)) 303 return 0; 304 } 305 #endif 306 return 1; 307 } 308 309 static const OSSL_PARAM known_settable_ctx_params[] = { 310 OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_DIGEST, NULL, 0), 311 OSSL_PARAM_utf8_string(OSSL_MAC_PARAM_PROPERTIES, NULL, 0), 312 OSSL_PARAM_octet_string(OSSL_MAC_PARAM_KEY, NULL, 0), 313 OSSL_PARAM_int(OSSL_MAC_PARAM_DIGEST_NOINIT, NULL), 314 OSSL_PARAM_int(OSSL_MAC_PARAM_DIGEST_ONESHOT, NULL), 315 OSSL_PARAM_size_t(OSSL_MAC_PARAM_TLS_DATA_SIZE, NULL), 316 OSSL_FIPS_IND_SETTABLE_CTX_PARAM(OSSL_MAC_PARAM_FIPS_KEY_CHECK) 317 OSSL_PARAM_END 318 }; 319 static const OSSL_PARAM *hmac_settable_ctx_params(ossl_unused void *ctx, 320 ossl_unused void *provctx) 321 { 322 return known_settable_ctx_params; 323 } 324 325 /* 326 * ALL parameters should be set before init(). 327 */ 328 static int hmac_set_ctx_params(void *vmacctx, const OSSL_PARAM params[]) 329 { 330 struct hmac_data_st *macctx = vmacctx; 331 OSSL_LIB_CTX *ctx = PROV_LIBCTX_OF(macctx->provctx); 332 const OSSL_PARAM *p; 333 334 if (ossl_param_is_empty(params)) 335 return 1; 336 337 if (!OSSL_FIPS_IND_SET_CTX_PARAM(macctx, OSSL_FIPS_IND_SETTABLE0, params, 338 OSSL_MAC_PARAM_FIPS_KEY_CHECK)) 339 return 0; 340 341 if (!ossl_prov_digest_load_from_params(&macctx->digest, params, ctx)) 342 return 0; 343 344 if ((p = OSSL_PARAM_locate_const(params, OSSL_MAC_PARAM_KEY)) != NULL) { 345 if (p->data_type != OSSL_PARAM_OCTET_STRING) 346 return 0; 347 348 if (!hmac_setkey(macctx, p->data, p->data_size)) 349 return 0; 350 } 351 352 if ((p = OSSL_PARAM_locate_const(params, 353 OSSL_MAC_PARAM_TLS_DATA_SIZE)) != NULL) { 354 if (!OSSL_PARAM_get_size_t(p, &macctx->tls_data_size)) 355 return 0; 356 } 357 return 1; 358 } 359 360 const OSSL_DISPATCH ossl_hmac_functions[] = { 361 { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))hmac_new }, 362 { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))hmac_dup }, 363 { OSSL_FUNC_MAC_FREECTX, (void (*)(void))hmac_free }, 364 { OSSL_FUNC_MAC_INIT, (void (*)(void))hmac_init }, 365 { OSSL_FUNC_MAC_UPDATE, (void (*)(void))hmac_update }, 366 { OSSL_FUNC_MAC_FINAL, (void (*)(void))hmac_final }, 367 { OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS, 368 (void (*)(void))hmac_gettable_ctx_params }, 369 { OSSL_FUNC_MAC_GET_CTX_PARAMS, (void (*)(void))hmac_get_ctx_params }, 370 { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS, 371 (void (*)(void))hmac_settable_ctx_params }, 372 { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))hmac_set_ctx_params }, 373 OSSL_DISPATCH_END 374 }; 375 376 #ifdef FIPS_MODULE 377 static OSSL_FUNC_mac_newctx_fn hmac_internal_new; 378 379 static void *hmac_internal_new(void *provctx) 380 { 381 struct hmac_data_st *macctx = hmac_new(provctx); 382 383 if (macctx != NULL) 384 macctx->internal = 1; 385 return macctx; 386 } 387 388 const OSSL_DISPATCH ossl_hmac_internal_functions[] = { 389 { OSSL_FUNC_MAC_NEWCTX, (void (*)(void))hmac_internal_new }, 390 { OSSL_FUNC_MAC_DUPCTX, (void (*)(void))hmac_dup }, 391 { OSSL_FUNC_MAC_FREECTX, (void (*)(void))hmac_free }, 392 { OSSL_FUNC_MAC_INIT, (void (*)(void))hmac_init }, 393 { OSSL_FUNC_MAC_UPDATE, (void (*)(void))hmac_update }, 394 { OSSL_FUNC_MAC_FINAL, (void (*)(void))hmac_final }, 395 { OSSL_FUNC_MAC_GETTABLE_CTX_PARAMS, 396 (void (*)(void))hmac_gettable_ctx_params }, 397 { OSSL_FUNC_MAC_GET_CTX_PARAMS, (void (*)(void))hmac_get_ctx_params }, 398 { OSSL_FUNC_MAC_SETTABLE_CTX_PARAMS, 399 (void (*)(void))hmac_settable_ctx_params }, 400 { OSSL_FUNC_MAC_SET_CTX_PARAMS, (void (*)(void))hmac_set_ctx_params }, 401 OSSL_DISPATCH_END 402 }; 403 404 #endif /* FIPS_MODULE */ 405