2 * Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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
12 #include <openssl/crypto.h>
13 #include "modes_lcl.h"
15 #ifndef OPENSSL_NO_SIV
17 __owur static ossl_inline uint32_t rotl8(uint32_t x)
19 return (x << 8) | (x >> 24);
22 __owur static ossl_inline uint32_t rotr8(uint32_t x)
24 return (x >> 8) | (x << 24);
27 __owur static ossl_inline uint64_t byteswap8(uint64_t x)
29 uint32_t high = (uint32_t)(x >> 32);
30 uint32_t low = (uint32_t)x;
32 high = (rotl8(high) & 0x00ff00ff) | (rotr8(high) & 0xff00ff00);
33 low = (rotl8(low) & 0x00ff00ff) | (rotr8(low) & 0xff00ff00);
34 return ((uint64_t)low) << 32 | (uint64_t)high;
37 __owur static ossl_inline uint64_t siv128_getword(SIV_BLOCK const *b, size_t i)
45 return byteswap8(b->word[i]);
49 static ossl_inline void siv128_putword(SIV_BLOCK *b, size_t i, uint64_t x)
57 b->word[i] = byteswap8(x);
62 static ossl_inline void siv128_xorblock(SIV_BLOCK *x,
65 x->word[0] ^= y->word[0];
66 x->word[1] ^= y->word[1];
70 * Doubles |b|, which is 16 bytes representing an element
71 * of GF(2**128) modulo the irreducible polynomial
72 * x**128 + x**7 + x**2 + x + 1.
73 * Assumes two's-complement arithmetic
75 static ossl_inline void siv128_dbl(SIV_BLOCK *b)
77 uint64_t high = siv128_getword(b, 0);
78 uint64_t low = siv128_getword(b, 1);
79 uint64_t high_carry = high & (((uint64_t)1) << 63);
80 uint64_t low_carry = low & (((uint64_t)1) << 63);
81 int64_t low_mask = -((int64_t)(high_carry >> 63)) & 0x87;
82 uint64_t high_mask = low_carry >> 63;
84 high = (high << 1) | high_mask;
85 low = (low << 1) ^ (uint64_t)low_mask;
86 siv128_putword(b, 0, high);
87 siv128_putword(b, 1, low);
90 __owur static ossl_inline int siv128_do_s2v_p(SIV128_CONTEXT *ctx, SIV_BLOCK *out,
91 unsigned char const* in, size_t len)
94 size_t out_len = sizeof(out->byte);
98 mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init);
102 if (len >= SIV_LEN) {
103 if (!EVP_MAC_update(mac_ctx, in, len - SIV_LEN))
105 memcpy(&t, in + (len-SIV_LEN), SIV_LEN);
106 siv128_xorblock(&t, &ctx->d);
107 if (!EVP_MAC_update(mac_ctx, t.byte, SIV_LEN))
110 memset(&t, 0, sizeof(t));
114 siv128_xorblock(&t, &ctx->d);
115 if (!EVP_MAC_update(mac_ctx, t.byte, SIV_LEN))
118 if (!EVP_MAC_final(mac_ctx, out->byte, &out_len)
119 || out_len != SIV_LEN)
125 EVP_MAC_CTX_free(mac_ctx);
130 __owur static ossl_inline int siv128_do_encrypt(EVP_CIPHER_CTX *ctx, unsigned char *out,
131 unsigned char const *in, size_t len,
134 int out_len = (int)len;
136 if (!EVP_CipherInit_ex(ctx, NULL, NULL, NULL, icv->byte, 1))
138 return EVP_EncryptUpdate(ctx, out, &out_len, in, out_len);
142 * Create a new SIV128_CONTEXT
144 SIV128_CONTEXT *CRYPTO_siv128_new(const unsigned char *key, int klen, EVP_CIPHER* cbc, EVP_CIPHER* ctr)
149 if ((ctx = OPENSSL_malloc(sizeof(*ctx))) != NULL) {
150 ret = CRYPTO_siv128_init(ctx, key, klen, cbc, ctr);
160 * Initialise an existing SIV128_CONTEXT
162 int CRYPTO_siv128_init(SIV128_CONTEXT *ctx, const unsigned char *key, int klen,
163 const EVP_CIPHER* cbc, const EVP_CIPHER* ctr)
165 static const unsigned char zero[SIV_LEN] = { 0 };
166 size_t out_len = SIV_LEN;
167 EVP_MAC_CTX *mac_ctx = NULL;
169 memset(&ctx->d, 0, sizeof(ctx->d));
170 ctx->cipher_ctx = NULL;
171 ctx->mac_ctx_init = NULL;
173 if (key == NULL || cbc == NULL || ctr == NULL
174 || (ctx->cipher_ctx = EVP_CIPHER_CTX_new()) == NULL
175 || (ctx->mac_ctx_init = EVP_MAC_CTX_new_id(EVP_MAC_CMAC)) == NULL
176 || EVP_MAC_ctrl(ctx->mac_ctx_init, EVP_MAC_CTRL_SET_CIPHER, cbc) <= 0
177 || EVP_MAC_ctrl(ctx->mac_ctx_init, EVP_MAC_CTRL_SET_KEY, key, klen) <= 0
178 || !EVP_EncryptInit_ex(ctx->cipher_ctx, ctr, NULL, key + klen, NULL)
179 || (mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init)) == NULL
180 || !EVP_MAC_update(mac_ctx, zero, sizeof(zero))
181 || !EVP_MAC_final(mac_ctx, ctx->d.byte, &out_len)) {
182 EVP_CIPHER_CTX_free(ctx->cipher_ctx);
183 EVP_MAC_CTX_free(ctx->mac_ctx_init);
184 EVP_MAC_CTX_free(mac_ctx);
187 EVP_MAC_CTX_free(mac_ctx);
196 * Copy an SIV128_CONTEXT object
198 int CRYPTO_siv128_copy_ctx(SIV128_CONTEXT *dest, SIV128_CONTEXT *src)
200 memcpy(&dest->d, &src->d, sizeof(src->d));
201 if (!EVP_CIPHER_CTX_copy(dest->cipher_ctx, src->cipher_ctx))
203 EVP_MAC_CTX_free(dest->mac_ctx_init);
204 dest->mac_ctx_init = EVP_MAC_CTX_dup(src->mac_ctx_init);
205 if (dest->mac_ctx_init == NULL)
211 * Provide any AAD. This can be called multiple times.
212 * Per RFC5297, the last piece of associated data
213 * is the nonce, but it's not treated special
215 int CRYPTO_siv128_aad(SIV128_CONTEXT *ctx, const unsigned char *aad,
219 size_t out_len = SIV_LEN;
220 EVP_MAC_CTX *mac_ctx;
224 mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init);
226 || !EVP_MAC_update(mac_ctx, aad, len)
227 || !EVP_MAC_final(mac_ctx, mac_out.byte, &out_len)
228 || out_len != SIV_LEN) {
229 EVP_MAC_CTX_free(mac_ctx);
232 EVP_MAC_CTX_free(mac_ctx);
234 siv128_xorblock(&ctx->d, &mac_out);
240 * Provide any data to be encrypted. This can be called once.
242 int CRYPTO_siv128_encrypt(SIV128_CONTEXT *ctx,
243 const unsigned char *in, unsigned char *out,
248 /* can only do one crypto operation */
249 if (ctx->crypto_ok == 0)
253 if (!siv128_do_s2v_p(ctx, &q, in, len))
256 memcpy(ctx->tag.byte, &q, SIV_LEN);
260 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q))
267 * Provide any data to be decrypted. This can be called once.
269 int CRYPTO_siv128_decrypt(SIV128_CONTEXT *ctx,
270 const unsigned char *in, unsigned char *out,
277 /* can only do one crypto operation */
278 if (ctx->crypto_ok == 0)
282 memcpy(&q, ctx->tag.byte, SIV_LEN);
286 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q)
287 || !siv128_do_s2v_p(ctx, &t, out, len))
291 for (i = 0; i < SIV_LEN; i++)
294 if ((t.word[0] | t.word[1]) != 0) {
295 OPENSSL_cleanse(out, len);
303 * Return the already calculated final result.
305 int CRYPTO_siv128_finish(SIV128_CONTEXT *ctx)
307 return ctx->final_ret;
313 int CRYPTO_siv128_set_tag(SIV128_CONTEXT *ctx, const unsigned char *tag, size_t len)
318 /* Copy the tag from the supplied buffer */
319 memcpy(ctx->tag.byte, tag, len);
324 * Retrieve the calculated tag
326 int CRYPTO_siv128_get_tag(SIV128_CONTEXT *ctx, unsigned char *tag, size_t len)
331 /* Copy the tag into the supplied buffer */
332 memcpy(tag, ctx->tag.byte, len);
337 * Release all resources
339 int CRYPTO_siv128_cleanup(SIV128_CONTEXT *ctx)
342 EVP_CIPHER_CTX_free(ctx->cipher_ctx);
343 ctx->cipher_ctx = NULL;
344 EVP_MAC_CTX_free(ctx->mac_ctx_init);
345 ctx->mac_ctx_init = NULL;
346 OPENSSL_cleanse(&ctx->d, sizeof(ctx->d));
347 OPENSSL_cleanse(&ctx->tag, sizeof(ctx->tag));
354 int CRYPTO_siv128_speed(SIV128_CONTEXT *ctx, int arg)
356 ctx->crypto_ok = (arg == 1) ? -1 : 1;
360 #endif /* OPENSSL_NO_SIV */