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 <openssl/evp.h>
14 #include "internal/modes_int.h"
15 #include "internal/siv_int.h"
17 #ifndef OPENSSL_NO_SIV
19 __owur static ossl_inline uint32_t rotl8(uint32_t x)
21 return (x << 8) | (x >> 24);
24 __owur static ossl_inline uint32_t rotr8(uint32_t x)
26 return (x >> 8) | (x << 24);
29 __owur static ossl_inline uint64_t byteswap8(uint64_t x)
31 uint32_t high = (uint32_t)(x >> 32);
32 uint32_t low = (uint32_t)x;
34 high = (rotl8(high) & 0x00ff00ff) | (rotr8(high) & 0xff00ff00);
35 low = (rotl8(low) & 0x00ff00ff) | (rotr8(low) & 0xff00ff00);
36 return ((uint64_t)low) << 32 | (uint64_t)high;
39 __owur static ossl_inline uint64_t siv128_getword(SIV_BLOCK const *b, size_t i)
47 return byteswap8(b->word[i]);
51 static ossl_inline void siv128_putword(SIV_BLOCK *b, size_t i, uint64_t x)
59 b->word[i] = byteswap8(x);
64 static ossl_inline void siv128_xorblock(SIV_BLOCK *x,
67 x->word[0] ^= y->word[0];
68 x->word[1] ^= y->word[1];
72 * Doubles |b|, which is 16 bytes representing an element
73 * of GF(2**128) modulo the irreducible polynomial
74 * x**128 + x**7 + x**2 + x + 1.
75 * Assumes two's-complement arithmetic
77 static ossl_inline void siv128_dbl(SIV_BLOCK *b)
79 uint64_t high = siv128_getword(b, 0);
80 uint64_t low = siv128_getword(b, 1);
81 uint64_t high_carry = high & (((uint64_t)1) << 63);
82 uint64_t low_carry = low & (((uint64_t)1) << 63);
83 int64_t low_mask = -((int64_t)(high_carry >> 63)) & 0x87;
84 uint64_t high_mask = low_carry >> 63;
86 high = (high << 1) | high_mask;
87 low = (low << 1) ^ (uint64_t)low_mask;
88 siv128_putword(b, 0, high);
89 siv128_putword(b, 1, low);
92 __owur static ossl_inline int siv128_do_s2v_p(SIV128_CONTEXT *ctx, SIV_BLOCK *out,
93 unsigned char const* in, size_t len)
96 size_t out_len = sizeof(out->byte);
100 mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init);
104 if (len >= SIV_LEN) {
105 if (!EVP_MAC_update(mac_ctx, in, len - SIV_LEN))
107 memcpy(&t, in + (len-SIV_LEN), SIV_LEN);
108 siv128_xorblock(&t, &ctx->d);
109 if (!EVP_MAC_update(mac_ctx, t.byte, SIV_LEN))
112 memset(&t, 0, sizeof(t));
116 siv128_xorblock(&t, &ctx->d);
117 if (!EVP_MAC_update(mac_ctx, t.byte, SIV_LEN))
120 if (!EVP_MAC_final(mac_ctx, out->byte, &out_len)
121 || out_len != SIV_LEN)
127 EVP_MAC_CTX_free(mac_ctx);
132 __owur static ossl_inline int siv128_do_encrypt(EVP_CIPHER_CTX *ctx, unsigned char *out,
133 unsigned char const *in, size_t len,
136 int out_len = (int)len;
138 if (!EVP_CipherInit_ex(ctx, NULL, NULL, NULL, icv->byte, 1))
140 return EVP_EncryptUpdate(ctx, out, &out_len, in, out_len);
144 * Create a new SIV128_CONTEXT
146 SIV128_CONTEXT *CRYPTO_siv128_new(const unsigned char *key, int klen, EVP_CIPHER* cbc, EVP_CIPHER* ctr)
151 if ((ctx = OPENSSL_malloc(sizeof(*ctx))) != NULL) {
152 ret = CRYPTO_siv128_init(ctx, key, klen, cbc, ctr);
162 * Initialise an existing SIV128_CONTEXT
164 int CRYPTO_siv128_init(SIV128_CONTEXT *ctx, const unsigned char *key, int klen,
165 const EVP_CIPHER* cbc, const EVP_CIPHER* ctr)
167 static const unsigned char zero[SIV_LEN] = { 0 };
168 size_t out_len = SIV_LEN;
169 EVP_MAC_CTX *mac_ctx = NULL;
171 memset(&ctx->d, 0, sizeof(ctx->d));
172 ctx->cipher_ctx = NULL;
173 ctx->mac_ctx_init = NULL;
175 if (key == NULL || cbc == NULL || ctr == NULL
176 || (ctx->cipher_ctx = EVP_CIPHER_CTX_new()) == NULL
177 || (ctx->mac_ctx_init = EVP_MAC_CTX_new_id(EVP_MAC_CMAC)) == NULL
178 || EVP_MAC_ctrl(ctx->mac_ctx_init, EVP_MAC_CTRL_SET_CIPHER, cbc) <= 0
179 || EVP_MAC_ctrl(ctx->mac_ctx_init, EVP_MAC_CTRL_SET_KEY, key, klen) <= 0
180 || !EVP_EncryptInit_ex(ctx->cipher_ctx, ctr, NULL, key + klen, NULL)
181 || (mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init)) == NULL
182 || !EVP_MAC_update(mac_ctx, zero, sizeof(zero))
183 || !EVP_MAC_final(mac_ctx, ctx->d.byte, &out_len)) {
184 EVP_CIPHER_CTX_free(ctx->cipher_ctx);
185 EVP_MAC_CTX_free(ctx->mac_ctx_init);
186 EVP_MAC_CTX_free(mac_ctx);
189 EVP_MAC_CTX_free(mac_ctx);
198 * Copy an SIV128_CONTEXT object
200 int CRYPTO_siv128_copy_ctx(SIV128_CONTEXT *dest, SIV128_CONTEXT *src)
202 memcpy(&dest->d, &src->d, sizeof(src->d));
203 if (!EVP_CIPHER_CTX_copy(dest->cipher_ctx, src->cipher_ctx))
205 EVP_MAC_CTX_free(dest->mac_ctx_init);
206 dest->mac_ctx_init = EVP_MAC_CTX_dup(src->mac_ctx_init);
207 if (dest->mac_ctx_init == NULL)
213 * Provide any AAD. This can be called multiple times.
214 * Per RFC5297, the last piece of associated data
215 * is the nonce, but it's not treated special
217 int CRYPTO_siv128_aad(SIV128_CONTEXT *ctx, const unsigned char *aad,
221 size_t out_len = SIV_LEN;
222 EVP_MAC_CTX *mac_ctx;
226 mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init);
228 || !EVP_MAC_update(mac_ctx, aad, len)
229 || !EVP_MAC_final(mac_ctx, mac_out.byte, &out_len)
230 || out_len != SIV_LEN) {
231 EVP_MAC_CTX_free(mac_ctx);
234 EVP_MAC_CTX_free(mac_ctx);
236 siv128_xorblock(&ctx->d, &mac_out);
242 * Provide any data to be encrypted. This can be called once.
244 int CRYPTO_siv128_encrypt(SIV128_CONTEXT *ctx,
245 const unsigned char *in, unsigned char *out,
250 /* can only do one crypto operation */
251 if (ctx->crypto_ok == 0)
255 if (!siv128_do_s2v_p(ctx, &q, in, len))
258 memcpy(ctx->tag.byte, &q, SIV_LEN);
262 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q))
269 * Provide any data to be decrypted. This can be called once.
271 int CRYPTO_siv128_decrypt(SIV128_CONTEXT *ctx,
272 const unsigned char *in, unsigned char *out,
279 /* can only do one crypto operation */
280 if (ctx->crypto_ok == 0)
284 memcpy(&q, ctx->tag.byte, SIV_LEN);
288 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q)
289 || !siv128_do_s2v_p(ctx, &t, out, len))
293 for (i = 0; i < SIV_LEN; i++)
296 if ((t.word[0] | t.word[1]) != 0) {
297 OPENSSL_cleanse(out, len);
305 * Return the already calculated final result.
307 int CRYPTO_siv128_finish(SIV128_CONTEXT *ctx)
309 return ctx->final_ret;
315 int CRYPTO_siv128_set_tag(SIV128_CONTEXT *ctx, const unsigned char *tag, size_t len)
320 /* Copy the tag from the supplied buffer */
321 memcpy(ctx->tag.byte, tag, len);
326 * Retrieve the calculated tag
328 int CRYPTO_siv128_get_tag(SIV128_CONTEXT *ctx, unsigned char *tag, size_t len)
333 /* Copy the tag into the supplied buffer */
334 memcpy(tag, ctx->tag.byte, len);
339 * Release all resources
341 int CRYPTO_siv128_cleanup(SIV128_CONTEXT *ctx)
344 EVP_CIPHER_CTX_free(ctx->cipher_ctx);
345 ctx->cipher_ctx = NULL;
346 EVP_MAC_CTX_free(ctx->mac_ctx_init);
347 ctx->mac_ctx_init = NULL;
348 OPENSSL_cleanse(&ctx->d, sizeof(ctx->d));
349 OPENSSL_cleanse(&ctx->tag, sizeof(ctx->tag));
356 int CRYPTO_siv128_speed(SIV128_CONTEXT *ctx, int arg)
358 ctx->crypto_ok = (arg == 1) ? -1 : 1;
362 #endif /* OPENSSL_NO_SIV */