1 /* 2 * Copyright 2019-2024 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 (ctx == NULL) 75 return NULL; 76 dctx = OPENSSL_memdup(ctx, sizeof(*ctx)); 77 78 if (dctx != NULL && dctx->base.tlsmac != NULL && dctx->base.alloced) { 79 dctx->base.tlsmac = OPENSSL_memdup(dctx->base.tlsmac, 80 dctx->base.tlsmacsize); 81 if (dctx->base.tlsmac == NULL) { 82 OPENSSL_free(dctx); 83 dctx = NULL; 84 } 85 } 86 return dctx; 87 } 88 89 static void aes_wrap_freectx(void *vctx) 90 { 91 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx; 92 93 ossl_cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx); 94 OPENSSL_clear_free(wctx, sizeof(*wctx)); 95 } 96 97 static int aes_wrap_init(void *vctx, const unsigned char *key, 98 size_t keylen, const unsigned char *iv, 99 size_t ivlen, const OSSL_PARAM params[], int enc) 100 { 101 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx; 102 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx; 103 104 if (!ossl_prov_is_running()) 105 return 0; 106 107 ctx->enc = enc; 108 if (ctx->pad) 109 wctx->wrapfn = enc ? CRYPTO_128_wrap_pad : CRYPTO_128_unwrap_pad; 110 else 111 wctx->wrapfn = enc ? CRYPTO_128_wrap : CRYPTO_128_unwrap; 112 113 if (iv != NULL) { 114 if (!ossl_cipher_generic_initiv(ctx, iv, ivlen)) 115 return 0; 116 } 117 if (key != NULL) { 118 int use_forward_transform; 119 120 if (keylen != ctx->keylen) { 121 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); 122 return 0; 123 } 124 /* 125 * See SP800-38F : Section 5.1 126 * The forward and inverse transformations for the AES block 127 * cipher—called “cipher” and “inverse cipher” are informally known as 128 * the AES encryption and AES decryption functions, respectively. 129 * If the designated cipher function for a key-wrap algorithm is chosen 130 * to be the AES decryption function, then CIPH-1K will be the AES 131 * encryption function. 132 */ 133 if (ctx->inverse_cipher == 0) 134 use_forward_transform = ctx->enc; 135 else 136 use_forward_transform = !ctx->enc; 137 if (use_forward_transform) { 138 AES_set_encrypt_key(key, keylen * 8, &wctx->ks.ks); 139 ctx->block = (block128_f)AES_encrypt; 140 } else { 141 AES_set_decrypt_key(key, keylen * 8, &wctx->ks.ks); 142 ctx->block = (block128_f)AES_decrypt; 143 } 144 } 145 return aes_wrap_set_ctx_params(ctx, params); 146 } 147 148 static int aes_wrap_einit(void *ctx, const unsigned char *key, size_t keylen, 149 const unsigned char *iv, size_t ivlen, 150 const OSSL_PARAM params[]) 151 { 152 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 1); 153 } 154 155 static int aes_wrap_dinit(void *ctx, const unsigned char *key, size_t keylen, 156 const unsigned char *iv, size_t ivlen, 157 const OSSL_PARAM params[]) 158 { 159 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 0); 160 } 161 162 static int aes_wrap_cipher_internal(void *vctx, unsigned char *out, 163 const unsigned char *in, size_t inlen) 164 { 165 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx; 166 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx; 167 size_t rv; 168 int pad = ctx->pad; 169 170 /* No final operation so always return zero length */ 171 if (in == NULL) 172 return 0; 173 174 /* Input length must always be non-zero */ 175 if (inlen == 0) { 176 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH); 177 return -1; 178 } 179 180 /* If decrypting need at least 16 bytes and multiple of 8 */ 181 if (!ctx->enc && (inlen < 16 || inlen & 0x7)) { 182 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH); 183 return -1; 184 } 185 186 /* If not padding input must be multiple of 8 */ 187 if (!pad && inlen & 0x7) { 188 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH); 189 return -1; 190 } 191 192 if (out == NULL) { 193 if (ctx->enc) { 194 /* If padding round up to multiple of 8 */ 195 if (pad) 196 inlen = (inlen + 7) / 8 * 8; 197 /* 8 byte prefix */ 198 return inlen + 8; 199 } else { 200 /* 201 * If not padding output will be exactly 8 bytes smaller than 202 * input. If padding it will be at least 8 bytes smaller but we 203 * don't know how much. 204 */ 205 return inlen - 8; 206 } 207 } 208 209 rv = wctx->wrapfn(&wctx->ks.ks, ctx->iv_set ? ctx->iv : NULL, out, in, 210 inlen, ctx->block); 211 if (!rv) { 212 ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED); 213 return -1; 214 } 215 if (rv > INT_MAX) { 216 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_OUTPUT_LENGTH); 217 return -1; 218 } 219 return (int)rv; 220 } 221 222 static int aes_wrap_final(void *vctx, unsigned char *out, size_t *outl, 223 size_t outsize) 224 { 225 if (!ossl_prov_is_running()) 226 return 0; 227 228 *outl = 0; 229 return 1; 230 } 231 232 static int aes_wrap_cipher(void *vctx, 233 unsigned char *out, size_t *outl, size_t outsize, 234 const unsigned char *in, size_t inl) 235 { 236 PROV_AES_WRAP_CTX *ctx = (PROV_AES_WRAP_CTX *)vctx; 237 size_t len; 238 239 if (!ossl_prov_is_running()) 240 return 0; 241 242 if (inl == 0) { 243 *outl = 0; 244 return 1; 245 } 246 247 if (outsize < inl) { 248 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL); 249 return 0; 250 } 251 252 len = aes_wrap_cipher_internal(ctx, out, in, inl); 253 if (len <= 0) 254 return 0; 255 256 *outl = len; 257 return 1; 258 } 259 260 static int aes_wrap_set_ctx_params(void *vctx, const OSSL_PARAM params[]) 261 { 262 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx; 263 const OSSL_PARAM *p; 264 size_t keylen = 0; 265 266 if (params == NULL) 267 return 1; 268 269 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN); 270 if (p != NULL) { 271 if (!OSSL_PARAM_get_size_t(p, &keylen)) { 272 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); 273 return 0; 274 } 275 if (ctx->keylen != keylen) { 276 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); 277 return 0; 278 } 279 } 280 return 1; 281 } 282 283 #define IMPLEMENT_cipher(mode, fname, UCMODE, flags, kbits, blkbits, ivbits) \ 284 static OSSL_FUNC_cipher_get_params_fn aes_##kbits##_##fname##_get_params; \ 285 static int aes_##kbits##_##fname##_get_params(OSSL_PARAM params[]) \ 286 { \ 287 return ossl_cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE,\ 288 flags, kbits, blkbits, ivbits); \ 289 } \ 290 static OSSL_FUNC_cipher_newctx_fn aes_##kbits##fname##_newctx; \ 291 static void *aes_##kbits##fname##_newctx(void *provctx) \ 292 { \ 293 return aes_##mode##_newctx(kbits, blkbits, ivbits, \ 294 EVP_CIPH_##UCMODE##_MODE, flags); \ 295 } \ 296 const OSSL_DISPATCH ossl_##aes##kbits##fname##_functions[] = { \ 297 { OSSL_FUNC_CIPHER_NEWCTX, \ 298 (void (*)(void))aes_##kbits##fname##_newctx }, \ 299 { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_##mode##_einit }, \ 300 { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_##mode##_dinit }, \ 301 { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_##mode##_cipher }, \ 302 { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_##mode##_final }, \ 303 { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_##mode##_freectx }, \ 304 { OSSL_FUNC_CIPHER_DUPCTX, (void (*)(void))aes_##mode##_dupctx }, \ 305 { OSSL_FUNC_CIPHER_GET_PARAMS, \ 306 (void (*)(void))aes_##kbits##_##fname##_get_params }, \ 307 { OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \ 308 (void (*)(void))ossl_cipher_generic_gettable_params }, \ 309 { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, \ 310 (void (*)(void))ossl_cipher_generic_get_ctx_params }, \ 311 { OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \ 312 (void (*)(void))aes_wrap_set_ctx_params }, \ 313 { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \ 314 (void (*)(void))ossl_cipher_generic_gettable_ctx_params }, \ 315 { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \ 316 (void (*)(void))ossl_cipher_generic_settable_ctx_params }, \ 317 { 0, NULL } \ 318 } 319 320 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_NOPAD_IVLEN * 8); 321 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_NOPAD_IVLEN * 8); 322 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_NOPAD_IVLEN * 8); 323 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_PAD_IVLEN * 8); 324 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_PAD_IVLEN * 8); 325 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_PAD_IVLEN * 8); 326 327 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_NOPAD_IVLEN * 8); 328 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_NOPAD_IVLEN * 8); 329 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_NOPAD_IVLEN * 8); 330 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_PAD_IVLEN * 8); 331 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_PAD_IVLEN * 8); 332 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_PAD_IVLEN * 8); 333