1 /* 2 * Copyright 2019-2023 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 /* 11 * This file uses the low level AES functions (which are deprecated for 12 * non-internal use) in order to implement provider AES ciphers. 13 */ 14 #include "internal/deprecated.h" 15 16 #include <openssl/proverr.h> 17 #include "cipher_aes.h" 18 #include "prov/providercommon.h" 19 #include "prov/implementations.h" 20 21 /* AES wrap with padding has IV length of 4, without padding 8 */ 22 #define AES_WRAP_PAD_IVLEN 4 23 #define AES_WRAP_NOPAD_IVLEN 8 24 25 #define WRAP_FLAGS (PROV_CIPHER_FLAG_CUSTOM_IV) 26 #define WRAP_FLAGS_INV (WRAP_FLAGS | PROV_CIPHER_FLAG_INVERSE_CIPHER) 27 28 typedef size_t (*aeswrap_fn)(void *key, const unsigned char *iv, 29 unsigned char *out, const unsigned char *in, 30 size_t inlen, block128_f block); 31 32 static OSSL_FUNC_cipher_encrypt_init_fn aes_wrap_einit; 33 static OSSL_FUNC_cipher_decrypt_init_fn aes_wrap_dinit; 34 static OSSL_FUNC_cipher_update_fn aes_wrap_cipher; 35 static OSSL_FUNC_cipher_final_fn aes_wrap_final; 36 static OSSL_FUNC_cipher_freectx_fn aes_wrap_freectx; 37 static OSSL_FUNC_cipher_set_ctx_params_fn aes_wrap_set_ctx_params; 38 39 typedef struct prov_aes_wrap_ctx_st { 40 PROV_CIPHER_CTX base; 41 union { 42 OSSL_UNION_ALIGN; 43 AES_KEY ks; 44 } ks; 45 aeswrap_fn wrapfn; 46 47 } PROV_AES_WRAP_CTX; 48 49 50 static void *aes_wrap_newctx(size_t kbits, size_t blkbits, 51 size_t ivbits, unsigned int mode, uint64_t flags) 52 { 53 PROV_AES_WRAP_CTX *wctx; 54 PROV_CIPHER_CTX *ctx; 55 56 if (!ossl_prov_is_running()) 57 return NULL; 58 59 wctx = OPENSSL_zalloc(sizeof(*wctx)); 60 ctx = (PROV_CIPHER_CTX *)wctx; 61 if (ctx != NULL) { 62 ossl_cipher_generic_initkey(ctx, kbits, blkbits, ivbits, mode, flags, 63 NULL, NULL); 64 ctx->pad = (ctx->ivlen == AES_WRAP_PAD_IVLEN); 65 } 66 return wctx; 67 } 68 69 static void *aes_wrap_dupctx(void *wctx) 70 { 71 PROV_AES_WRAP_CTX *ctx = wctx; 72 PROV_AES_WRAP_CTX *dctx = wctx; 73 74 if (!ossl_prov_is_running()) 75 return NULL; 76 77 if (ctx == NULL) 78 return NULL; 79 dctx = OPENSSL_memdup(ctx, sizeof(*ctx)); 80 81 if (dctx != NULL && dctx->base.tlsmac != NULL && dctx->base.alloced) { 82 dctx->base.tlsmac = OPENSSL_memdup(dctx->base.tlsmac, 83 dctx->base.tlsmacsize); 84 if (dctx->base.tlsmac == NULL) { 85 OPENSSL_free(dctx); 86 dctx = NULL; 87 } 88 } 89 return dctx; 90 } 91 92 static void aes_wrap_freectx(void *vctx) 93 { 94 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx; 95 96 ossl_cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx); 97 OPENSSL_clear_free(wctx, sizeof(*wctx)); 98 } 99 100 static int aes_wrap_init(void *vctx, const unsigned char *key, 101 size_t keylen, const unsigned char *iv, 102 size_t ivlen, const OSSL_PARAM params[], int enc) 103 { 104 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx; 105 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx; 106 107 if (!ossl_prov_is_running()) 108 return 0; 109 110 ctx->enc = enc; 111 if (ctx->pad) 112 wctx->wrapfn = enc ? CRYPTO_128_wrap_pad : CRYPTO_128_unwrap_pad; 113 else 114 wctx->wrapfn = enc ? CRYPTO_128_wrap : CRYPTO_128_unwrap; 115 116 if (iv != NULL) { 117 if (!ossl_cipher_generic_initiv(ctx, iv, ivlen)) 118 return 0; 119 } 120 if (key != NULL) { 121 int use_forward_transform; 122 123 if (keylen != ctx->keylen) { 124 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); 125 return 0; 126 } 127 /* 128 * See SP800-38F : Section 5.1 129 * The forward and inverse transformations for the AES block 130 * cipher—called “cipher” and “inverse cipher” are informally known as 131 * the AES encryption and AES decryption functions, respectively. 132 * If the designated cipher function for a key-wrap algorithm is chosen 133 * to be the AES decryption function, then CIPH-1K will be the AES 134 * encryption function. 135 */ 136 if (ctx->inverse_cipher == 0) 137 use_forward_transform = ctx->enc; 138 else 139 use_forward_transform = !ctx->enc; 140 if (use_forward_transform) { 141 AES_set_encrypt_key(key, keylen * 8, &wctx->ks.ks); 142 ctx->block = (block128_f)AES_encrypt; 143 } else { 144 AES_set_decrypt_key(key, keylen * 8, &wctx->ks.ks); 145 ctx->block = (block128_f)AES_decrypt; 146 } 147 } 148 return aes_wrap_set_ctx_params(ctx, params); 149 } 150 151 static int aes_wrap_einit(void *ctx, const unsigned char *key, size_t keylen, 152 const unsigned char *iv, size_t ivlen, 153 const OSSL_PARAM params[]) 154 { 155 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 1); 156 } 157 158 static int aes_wrap_dinit(void *ctx, const unsigned char *key, size_t keylen, 159 const unsigned char *iv, size_t ivlen, 160 const OSSL_PARAM params[]) 161 { 162 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 0); 163 } 164 165 static int aes_wrap_cipher_internal(void *vctx, unsigned char *out, 166 const unsigned char *in, size_t inlen) 167 { 168 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx; 169 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx; 170 size_t rv; 171 int pad = ctx->pad; 172 173 /* No final operation so always return zero length */ 174 if (in == NULL) 175 return 0; 176 177 /* Input length must always be non-zero */ 178 if (inlen == 0) { 179 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH); 180 return -1; 181 } 182 183 /* If decrypting need at least 16 bytes and multiple of 8 */ 184 if (!ctx->enc && (inlen < 16 || inlen & 0x7)) { 185 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH); 186 return -1; 187 } 188 189 /* If not padding input must be multiple of 8 */ 190 if (!pad && inlen & 0x7) { 191 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH); 192 return -1; 193 } 194 195 if (out == NULL) { 196 if (ctx->enc) { 197 /* If padding round up to multiple of 8 */ 198 if (pad) 199 inlen = (inlen + 7) / 8 * 8; 200 /* 8 byte prefix */ 201 return inlen + 8; 202 } else { 203 /* 204 * If not padding output will be exactly 8 bytes smaller than 205 * input. If padding it will be at least 8 bytes smaller but we 206 * don't know how much. 207 */ 208 return inlen - 8; 209 } 210 } 211 212 rv = wctx->wrapfn(&wctx->ks.ks, ctx->iv_set ? ctx->iv : NULL, out, in, 213 inlen, ctx->block); 214 if (!rv) { 215 ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED); 216 return -1; 217 } 218 if (rv > INT_MAX) { 219 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_OUTPUT_LENGTH); 220 return -1; 221 } 222 return (int)rv; 223 } 224 225 static int aes_wrap_final(void *vctx, unsigned char *out, size_t *outl, 226 size_t outsize) 227 { 228 if (!ossl_prov_is_running()) 229 return 0; 230 231 *outl = 0; 232 return 1; 233 } 234 235 static int aes_wrap_cipher(void *vctx, 236 unsigned char *out, size_t *outl, size_t outsize, 237 const unsigned char *in, size_t inl) 238 { 239 PROV_AES_WRAP_CTX *ctx = (PROV_AES_WRAP_CTX *)vctx; 240 size_t len; 241 242 if (!ossl_prov_is_running()) 243 return 0; 244 245 if (inl == 0) { 246 *outl = 0; 247 return 1; 248 } 249 250 if (outsize < inl) { 251 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL); 252 return 0; 253 } 254 255 len = aes_wrap_cipher_internal(ctx, out, in, inl); 256 if (len <= 0) 257 return 0; 258 259 *outl = len; 260 return 1; 261 } 262 263 static int aes_wrap_set_ctx_params(void *vctx, const OSSL_PARAM params[]) 264 { 265 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx; 266 const OSSL_PARAM *p; 267 size_t keylen = 0; 268 269 if (ossl_param_is_empty(params)) 270 return 1; 271 272 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN); 273 if (p != NULL) { 274 if (!OSSL_PARAM_get_size_t(p, &keylen)) { 275 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); 276 return 0; 277 } 278 if (ctx->keylen != keylen) { 279 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); 280 return 0; 281 } 282 } 283 return 1; 284 } 285 286 #define IMPLEMENT_cipher(mode, fname, UCMODE, flags, kbits, blkbits, ivbits) \ 287 static OSSL_FUNC_cipher_get_params_fn aes_##kbits##_##fname##_get_params; \ 288 static int aes_##kbits##_##fname##_get_params(OSSL_PARAM params[]) \ 289 { \ 290 return ossl_cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE,\ 291 flags, kbits, blkbits, ivbits); \ 292 } \ 293 static OSSL_FUNC_cipher_newctx_fn aes_##kbits##fname##_newctx; \ 294 static void *aes_##kbits##fname##_newctx(void *provctx) \ 295 { \ 296 return aes_##mode##_newctx(kbits, blkbits, ivbits, \ 297 EVP_CIPH_##UCMODE##_MODE, flags); \ 298 } \ 299 const OSSL_DISPATCH ossl_##aes##kbits##fname##_functions[] = { \ 300 { OSSL_FUNC_CIPHER_NEWCTX, \ 301 (void (*)(void))aes_##kbits##fname##_newctx }, \ 302 { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_##mode##_einit }, \ 303 { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_##mode##_dinit }, \ 304 { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_##mode##_cipher }, \ 305 { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_##mode##_final }, \ 306 { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_##mode##_freectx }, \ 307 { OSSL_FUNC_CIPHER_DUPCTX, (void (*)(void))aes_##mode##_dupctx }, \ 308 { OSSL_FUNC_CIPHER_GET_PARAMS, \ 309 (void (*)(void))aes_##kbits##_##fname##_get_params }, \ 310 { OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \ 311 (void (*)(void))ossl_cipher_generic_gettable_params }, \ 312 { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, \ 313 (void (*)(void))ossl_cipher_generic_get_ctx_params }, \ 314 { OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \ 315 (void (*)(void))aes_wrap_set_ctx_params }, \ 316 { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \ 317 (void (*)(void))ossl_cipher_generic_gettable_ctx_params }, \ 318 { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \ 319 (void (*)(void))ossl_cipher_generic_settable_ctx_params }, \ 320 OSSL_DISPATCH_END \ 321 } 322 323 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_NOPAD_IVLEN * 8); 324 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_NOPAD_IVLEN * 8); 325 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_NOPAD_IVLEN * 8); 326 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_PAD_IVLEN * 8); 327 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_PAD_IVLEN * 8); 328 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_PAD_IVLEN * 8); 329 330 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_NOPAD_IVLEN * 8); 331 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_NOPAD_IVLEN * 8); 332 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_NOPAD_IVLEN * 8); 333 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_PAD_IVLEN * 8); 334 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_PAD_IVLEN * 8); 335 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_PAD_IVLEN * 8); 336