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 ccm mode */ 11 12 #include <openssl/proverr.h> 13 #include "prov/ciphercommon.h" 14 #include "prov/ciphercommon_ccm.h" 15 #include "prov/providercommon.h" 16 17 static int ccm_cipher_internal(PROV_CCM_CTX *ctx, unsigned char *out, 18 size_t *padlen, const unsigned char *in, 19 size_t len); 20 21 static int ccm_tls_init(PROV_CCM_CTX *ctx, unsigned char *aad, size_t alen) 22 { 23 size_t len; 24 25 if (!ossl_prov_is_running() || alen != EVP_AEAD_TLS1_AAD_LEN) 26 return 0; 27 28 /* Save the aad for later use. */ 29 memcpy(ctx->buf, aad, alen); 30 ctx->tls_aad_len = alen; 31 32 len = ctx->buf[alen - 2] << 8 | ctx->buf[alen - 1]; 33 if (len < EVP_CCM_TLS_EXPLICIT_IV_LEN) 34 return 0; 35 36 /* Correct length for explicit iv. */ 37 len -= EVP_CCM_TLS_EXPLICIT_IV_LEN; 38 39 if (!ctx->enc) { 40 if (len < ctx->m) 41 return 0; 42 /* Correct length for tag. */ 43 len -= ctx->m; 44 } 45 ctx->buf[alen - 2] = (unsigned char)(len >> 8); 46 ctx->buf[alen - 1] = (unsigned char)(len & 0xff); 47 48 /* Extra padding: tag appended to record. */ 49 return ctx->m; 50 } 51 52 static int ccm_tls_iv_set_fixed(PROV_CCM_CTX *ctx, unsigned char *fixed, 53 size_t flen) 54 { 55 if (flen != EVP_CCM_TLS_FIXED_IV_LEN) 56 return 0; 57 58 /* Copy to first part of the iv. */ 59 memcpy(ctx->iv, fixed, flen); 60 return 1; 61 } 62 63 static size_t ccm_get_ivlen(PROV_CCM_CTX *ctx) 64 { 65 return 15 - ctx->l; 66 } 67 68 int ossl_ccm_set_ctx_params(void *vctx, const OSSL_PARAM params[]) 69 { 70 PROV_CCM_CTX *ctx = (PROV_CCM_CTX *)vctx; 71 const OSSL_PARAM *p; 72 size_t sz; 73 74 if (params == NULL) 75 return 1; 76 77 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TAG); 78 if (p != NULL) { 79 if (p->data_type != OSSL_PARAM_OCTET_STRING) { 80 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); 81 return 0; 82 } 83 if ((p->data_size & 1) || (p->data_size < 4) || p->data_size > 16) { 84 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_TAG_LENGTH); 85 return 0; 86 } 87 88 if (p->data != NULL) { 89 if (ctx->enc) { 90 ERR_raise(ERR_LIB_PROV, PROV_R_TAG_NOT_NEEDED); 91 return 0; 92 } 93 memcpy(ctx->buf, p->data, p->data_size); 94 ctx->tag_set = 1; 95 } 96 ctx->m = p->data_size; 97 } 98 99 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_IVLEN); 100 if (p != NULL) { 101 size_t ivlen; 102 103 if (!OSSL_PARAM_get_size_t(p, &sz)) { 104 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); 105 return 0; 106 } 107 ivlen = 15 - sz; 108 if (ivlen < 2 || ivlen > 8) { 109 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); 110 return 0; 111 } 112 if (ctx->l != ivlen) { 113 ctx->l = ivlen; 114 ctx->iv_set = 0; 115 } 116 } 117 118 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TLS1_AAD); 119 if (p != NULL) { 120 if (p->data_type != OSSL_PARAM_OCTET_STRING) { 121 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); 122 return 0; 123 } 124 sz = ccm_tls_init(ctx, p->data, p->data_size); 125 if (sz == 0) { 126 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DATA); 127 return 0; 128 } 129 ctx->tls_aad_pad_sz = sz; 130 } 131 132 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TLS1_IV_FIXED); 133 if (p != NULL) { 134 if (p->data_type != OSSL_PARAM_OCTET_STRING) { 135 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); 136 return 0; 137 } 138 if (ccm_tls_iv_set_fixed(ctx, p->data, p->data_size) == 0) { 139 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); 140 return 0; 141 } 142 } 143 144 return 1; 145 } 146 147 int ossl_ccm_get_ctx_params(void *vctx, OSSL_PARAM params[]) 148 { 149 PROV_CCM_CTX *ctx = (PROV_CCM_CTX *)vctx; 150 OSSL_PARAM *p; 151 152 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_IVLEN); 153 if (p != NULL && !OSSL_PARAM_set_size_t(p, ccm_get_ivlen(ctx))) { 154 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 155 return 0; 156 } 157 158 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TAGLEN); 159 if (p != NULL) { 160 size_t m = ctx->m; 161 162 if (!OSSL_PARAM_set_size_t(p, m)) { 163 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 164 return 0; 165 } 166 } 167 168 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_IV); 169 if (p != NULL) { 170 if (ccm_get_ivlen(ctx) > p->data_size) { 171 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); 172 return 0; 173 } 174 if (!OSSL_PARAM_set_octet_string(p, ctx->iv, p->data_size) 175 && !OSSL_PARAM_set_octet_ptr(p, &ctx->iv, p->data_size)) { 176 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 177 return 0; 178 } 179 } 180 181 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_UPDATED_IV); 182 if (p != NULL) { 183 if (ccm_get_ivlen(ctx) > p->data_size) { 184 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); 185 return 0; 186 } 187 if (!OSSL_PARAM_set_octet_string(p, ctx->iv, p->data_size) 188 && !OSSL_PARAM_set_octet_ptr(p, &ctx->iv, p->data_size)) { 189 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 190 return 0; 191 } 192 } 193 194 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_KEYLEN); 195 if (p != NULL && !OSSL_PARAM_set_size_t(p, ctx->keylen)) { 196 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 197 return 0; 198 } 199 200 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD); 201 if (p != NULL && !OSSL_PARAM_set_size_t(p, ctx->tls_aad_pad_sz)) { 202 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 203 return 0; 204 } 205 206 p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TAG); 207 if (p != NULL) { 208 if (!ctx->enc || !ctx->tag_set) { 209 ERR_raise(ERR_LIB_PROV, PROV_R_TAG_NOT_SET); 210 return 0; 211 } 212 if (p->data_type != OSSL_PARAM_OCTET_STRING) { 213 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); 214 return 0; 215 } 216 if (!ctx->hw->gettag(ctx, p->data, p->data_size)) 217 return 0; 218 ctx->tag_set = 0; 219 ctx->iv_set = 0; 220 ctx->len_set = 0; 221 } 222 return 1; 223 } 224 225 static int ccm_init(void *vctx, const unsigned char *key, size_t keylen, 226 const unsigned char *iv, size_t ivlen, 227 const OSSL_PARAM params[], int enc) 228 { 229 PROV_CCM_CTX *ctx = (PROV_CCM_CTX *)vctx; 230 231 if (!ossl_prov_is_running()) 232 return 0; 233 234 ctx->enc = enc; 235 236 if (iv != NULL) { 237 if (ivlen != ccm_get_ivlen(ctx)) { 238 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); 239 return 0; 240 } 241 memcpy(ctx->iv, iv, ivlen); 242 ctx->iv_set = 1; 243 } 244 if (key != NULL) { 245 if (keylen != ctx->keylen) { 246 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); 247 return 0; 248 } 249 if (!ctx->hw->setkey(ctx, key, keylen)) 250 return 0; 251 } 252 return ossl_ccm_set_ctx_params(ctx, params); 253 } 254 255 int ossl_ccm_einit(void *vctx, const unsigned char *key, size_t keylen, 256 const unsigned char *iv, size_t ivlen, 257 const OSSL_PARAM params[]) 258 { 259 return ccm_init(vctx, key, keylen, iv, ivlen, params, 1); 260 } 261 262 int ossl_ccm_dinit(void *vctx, const unsigned char *key, size_t keylen, 263 const unsigned char *iv, size_t ivlen, 264 const OSSL_PARAM params[]) 265 { 266 return ccm_init(vctx, key, keylen, iv, ivlen, params, 0); 267 } 268 269 int ossl_ccm_stream_update(void *vctx, unsigned char *out, size_t *outl, 270 size_t outsize, const unsigned char *in, 271 size_t inl) 272 { 273 PROV_CCM_CTX *ctx = (PROV_CCM_CTX *)vctx; 274 275 if (outsize < inl) { 276 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL); 277 return 0; 278 } 279 280 if (!ccm_cipher_internal(ctx, out, outl, in, inl)) { 281 ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED); 282 return 0; 283 } 284 return 1; 285 } 286 287 int ossl_ccm_stream_final(void *vctx, unsigned char *out, size_t *outl, 288 size_t outsize) 289 { 290 PROV_CCM_CTX *ctx = (PROV_CCM_CTX *)vctx; 291 int i; 292 293 if (!ossl_prov_is_running()) 294 return 0; 295 296 i = ccm_cipher_internal(ctx, out, outl, NULL, 0); 297 if (i <= 0) 298 return 0; 299 300 *outl = 0; 301 return 1; 302 } 303 304 int ossl_ccm_cipher(void *vctx, unsigned char *out, size_t *outl, size_t outsize, 305 const unsigned char *in, size_t inl) 306 { 307 PROV_CCM_CTX *ctx = (PROV_CCM_CTX *)vctx; 308 309 if (!ossl_prov_is_running()) 310 return 0; 311 312 if (outsize < inl) { 313 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL); 314 return 0; 315 } 316 317 if (ccm_cipher_internal(ctx, out, outl, in, inl) <= 0) 318 return 0; 319 320 *outl = inl; 321 return 1; 322 } 323 324 /* Copy the buffered iv */ 325 static int ccm_set_iv(PROV_CCM_CTX *ctx, size_t mlen) 326 { 327 const PROV_CCM_HW *hw = ctx->hw; 328 329 if (!hw->setiv(ctx, ctx->iv, ccm_get_ivlen(ctx), mlen)) 330 return 0; 331 ctx->len_set = 1; 332 return 1; 333 } 334 335 static int ccm_tls_cipher(PROV_CCM_CTX *ctx, 336 unsigned char *out, size_t *padlen, 337 const unsigned char *in, size_t len) 338 { 339 int rv = 0; 340 size_t olen = 0; 341 342 if (!ossl_prov_is_running()) 343 goto err; 344 345 /* Encrypt/decrypt must be performed in place */ 346 if (in == NULL || out != in || len < EVP_CCM_TLS_EXPLICIT_IV_LEN + ctx->m) 347 goto err; 348 349 /* If encrypting set explicit IV from sequence number (start of AAD) */ 350 if (ctx->enc) 351 memcpy(out, ctx->buf, EVP_CCM_TLS_EXPLICIT_IV_LEN); 352 /* Get rest of IV from explicit IV */ 353 memcpy(ctx->iv + EVP_CCM_TLS_FIXED_IV_LEN, in, EVP_CCM_TLS_EXPLICIT_IV_LEN); 354 /* Correct length value */ 355 len -= EVP_CCM_TLS_EXPLICIT_IV_LEN + ctx->m; 356 if (!ccm_set_iv(ctx, len)) 357 goto err; 358 359 /* Use saved AAD */ 360 if (!ctx->hw->setaad(ctx, ctx->buf, ctx->tls_aad_len)) 361 goto err; 362 363 /* Fix buffer to point to payload */ 364 in += EVP_CCM_TLS_EXPLICIT_IV_LEN; 365 out += EVP_CCM_TLS_EXPLICIT_IV_LEN; 366 if (ctx->enc) { 367 if (!ctx->hw->auth_encrypt(ctx, in, out, len, out + len, ctx->m)) 368 goto err; 369 olen = len + EVP_CCM_TLS_EXPLICIT_IV_LEN + ctx->m; 370 } else { 371 if (!ctx->hw->auth_decrypt(ctx, in, out, len, 372 (unsigned char *)in + len, ctx->m)) 373 goto err; 374 olen = len; 375 } 376 rv = 1; 377 err: 378 *padlen = olen; 379 return rv; 380 } 381 382 static int ccm_cipher_internal(PROV_CCM_CTX *ctx, unsigned char *out, 383 size_t *padlen, const unsigned char *in, 384 size_t len) 385 { 386 int rv = 0; 387 size_t olen = 0; 388 const PROV_CCM_HW *hw = ctx->hw; 389 390 /* If no key set, return error */ 391 if (!ctx->key_set) 392 return 0; 393 394 if (ctx->tls_aad_len != UNINITIALISED_SIZET) 395 return ccm_tls_cipher(ctx, out, padlen, in, len); 396 397 /* EVP_*Final() doesn't return any data */ 398 if (in == NULL && out != NULL) 399 goto finish; 400 401 if (!ctx->iv_set) 402 goto err; 403 404 if (out == NULL) { 405 if (in == NULL) { 406 if (!ccm_set_iv(ctx, len)) 407 goto err; 408 } else { 409 /* If we have AAD, we need a message length */ 410 if (!ctx->len_set && len) 411 goto err; 412 if (!hw->setaad(ctx, in, len)) 413 goto err; 414 } 415 } else { 416 /* If not set length yet do it */ 417 if (!ctx->len_set && !ccm_set_iv(ctx, len)) 418 goto err; 419 420 if (ctx->enc) { 421 if (!hw->auth_encrypt(ctx, in, out, len, NULL, 0)) 422 goto err; 423 ctx->tag_set = 1; 424 } else { 425 /* The tag must be set before actually decrypting data */ 426 if (!ctx->tag_set) 427 goto err; 428 429 if (!hw->auth_decrypt(ctx, in, out, len, ctx->buf, ctx->m)) 430 goto err; 431 /* Finished - reset flags so calling this method again will fail */ 432 ctx->iv_set = 0; 433 ctx->tag_set = 0; 434 ctx->len_set = 0; 435 } 436 } 437 olen = len; 438 finish: 439 rv = 1; 440 err: 441 *padlen = olen; 442 return rv; 443 } 444 445 void ossl_ccm_initctx(PROV_CCM_CTX *ctx, size_t keybits, const PROV_CCM_HW *hw) 446 { 447 ctx->keylen = keybits / 8; 448 ctx->key_set = 0; 449 ctx->iv_set = 0; 450 ctx->tag_set = 0; 451 ctx->len_set = 0; 452 ctx->l = 8; 453 ctx->m = 12; 454 ctx->tls_aad_len = UNINITIALISED_SIZET; 455 ctx->hw = hw; 456 } 457