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git.ipfire.org Git - thirdparty/openssl.git/blob - crypto/modes/siv128.c
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 */