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);
96 if (!EVP_MAC_CTX_copy(ctx->mac_ctx, ctx->mac_ctx_init))
100 if (!EVP_MAC_update(ctx->mac_ctx, in, len - SIV_LEN))
102 memcpy(&t, in + (len-SIV_LEN), SIV_LEN);
103 siv128_xorblock(&t, &ctx->d);
104 if (!EVP_MAC_update(ctx->mac_ctx, t.byte, SIV_LEN))
107 memset(&t, 0, sizeof(t));
111 siv128_xorblock(&t, &ctx->d);
112 if (!EVP_MAC_update(ctx->mac_ctx, t.byte, SIV_LEN))
115 if (!EVP_MAC_final(ctx->mac_ctx, out->byte, &out_len)
116 || out_len != SIV_LEN)
122 __owur static ossl_inline int siv128_do_encrypt(EVP_CIPHER_CTX *ctx, unsigned char *out,
123 unsigned char const *in, size_t len,
126 int out_len = (int)len;
128 if (!EVP_CipherInit_ex(ctx, NULL, NULL, NULL, icv->byte, 1))
130 return EVP_EncryptUpdate(ctx, out, &out_len, in, out_len);
134 * Create a new SIV128_CONTEXT
136 SIV128_CONTEXT *CRYPTO_siv128_new(const unsigned char *key, int klen, EVP_CIPHER* cbc, EVP_CIPHER* ctr)
141 if ((ctx = OPENSSL_malloc(sizeof(*ctx))) != NULL) {
142 ret = CRYPTO_siv128_init(ctx, key, klen, cbc, ctr);
152 * Initialise an existing SIV128_CONTEXT
154 int CRYPTO_siv128_init(SIV128_CONTEXT *ctx, const unsigned char *key, int klen,
155 const EVP_CIPHER* cbc, const EVP_CIPHER* ctr)
157 static const unsigned char zero[SIV_LEN] = { 0 };
158 size_t out_len = SIV_LEN;
160 memset(&ctx->d, 0, sizeof(ctx->d));
161 ctx->cipher_ctx = NULL;
163 ctx->mac_ctx_init = NULL;
165 if (key == NULL || cbc == NULL || ctr == NULL
166 || (ctx->cipher_ctx = EVP_CIPHER_CTX_new()) == NULL
167 || (ctx->mac_ctx_init = EVP_MAC_CTX_new_id(EVP_MAC_CMAC)) == NULL
168 || (ctx->mac_ctx = EVP_MAC_CTX_new_id(EVP_MAC_CMAC)) == NULL
169 || !EVP_MAC_ctrl(ctx->mac_ctx_init, EVP_MAC_CTRL_SET_CIPHER, cbc)
170 || !EVP_MAC_ctrl(ctx->mac_ctx_init, EVP_MAC_CTRL_SET_KEY, key, klen)
171 || !EVP_EncryptInit_ex(ctx->cipher_ctx, ctr, NULL, key + klen, NULL)
172 || !EVP_MAC_CTX_copy(ctx->mac_ctx, ctx->mac_ctx_init)
173 || !EVP_MAC_update(ctx->mac_ctx, zero, sizeof(zero))
174 || !EVP_MAC_final(ctx->mac_ctx, ctx->d.byte, &out_len)) {
175 EVP_CIPHER_CTX_free(ctx->cipher_ctx);
176 EVP_MAC_CTX_free(ctx->mac_ctx_init);
177 EVP_MAC_CTX_free(ctx->mac_ctx);
188 * Copy an SIV128_CONTEXT object
190 int CRYPTO_siv128_copy_ctx(SIV128_CONTEXT *dest, SIV128_CONTEXT *src)
192 memcpy(&dest->d, &src->d, sizeof(src->d));
193 if (!EVP_CIPHER_CTX_copy(dest->cipher_ctx, src->cipher_ctx))
195 if (!EVP_MAC_CTX_copy(dest->mac_ctx_init, src->mac_ctx_init))
197 /* no need to copy mac_ctx since it's temp storage */
202 * Provide any AAD. This can be called multiple times.
203 * Per RFC5297, the last piece of associated data
204 * is the nonce, but it's not treated special
206 int CRYPTO_siv128_aad(SIV128_CONTEXT *ctx, const unsigned char *aad,
210 size_t out_len = SIV_LEN;
214 if (!EVP_MAC_CTX_copy(ctx->mac_ctx, ctx->mac_ctx_init)
215 || !EVP_MAC_update(ctx->mac_ctx, aad, len)
216 || !EVP_MAC_final(ctx->mac_ctx, mac_out.byte, &out_len)
217 || out_len != SIV_LEN)
220 siv128_xorblock(&ctx->d, &mac_out);
227 * Provide any data to be encrypted. This can be called once.
229 int CRYPTO_siv128_encrypt(SIV128_CONTEXT *ctx,
230 const unsigned char *in, unsigned char *out,
235 /* can only do one crypto operation */
236 if (ctx->crypto_ok == 0)
240 if (!siv128_do_s2v_p(ctx, &q, in, len))
243 memcpy(ctx->tag.byte, &q, SIV_LEN);
247 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q))
254 * Provide any data to be decrypted. This can be called once.
256 int CRYPTO_siv128_decrypt(SIV128_CONTEXT *ctx,
257 const unsigned char *in, unsigned char *out,
264 /* can only do one crypto operation */
265 if (ctx->crypto_ok == 0)
269 memcpy(&q, ctx->tag.byte, SIV_LEN);
273 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q)
274 || !siv128_do_s2v_p(ctx, &t, out, len))
278 for (i = 0; i < SIV_LEN; i++)
281 if ((t.word[0] | t.word[1]) != 0) {
282 OPENSSL_cleanse(out, len);
290 * Return the already calculated final result.
292 int CRYPTO_siv128_finish(SIV128_CONTEXT *ctx)
294 return ctx->final_ret;
300 int CRYPTO_siv128_set_tag(SIV128_CONTEXT *ctx, const unsigned char *tag, size_t len)
305 /* Copy the tag from the supplied buffer */
306 memcpy(ctx->tag.byte, tag, len);
311 * Retrieve the calculated tag
313 int CRYPTO_siv128_get_tag(SIV128_CONTEXT *ctx, unsigned char *tag, size_t len)
318 /* Copy the tag into the supplied buffer */
319 memcpy(tag, ctx->tag.byte, len);
324 * Release all resources
326 int CRYPTO_siv128_cleanup(SIV128_CONTEXT *ctx)
329 EVP_CIPHER_CTX_free(ctx->cipher_ctx);
330 ctx->cipher_ctx = NULL;
331 EVP_MAC_CTX_free(ctx->mac_ctx_init);
332 ctx->mac_ctx_init = NULL;
333 EVP_MAC_CTX_free(ctx->mac_ctx);
335 OPENSSL_cleanse(&ctx->d, sizeof(ctx->d));
336 OPENSSL_cleanse(&ctx->tag, sizeof(ctx->tag));
343 int CRYPTO_siv128_speed(SIV128_CONTEXT *ctx, int arg)
345 ctx->crypto_ok = (arg == 1) ? -1 : 1;
349 #endif /* OPENSSL_NO_SIV */