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[thirdparty/openssl.git] / crypto / modes / siv128.c
1 /*
2 * Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
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
8 */
9
10 #include <string.h>
11 #include <stdlib.h>
12 #include <openssl/crypto.h>
13 #include <openssl/evp.h>
14 #include "internal/modes_int.h"
15 #include "internal/siv_int.h"
16
17 #ifndef OPENSSL_NO_SIV
18
19 __owur static ossl_inline uint32_t rotl8(uint32_t x)
20 {
21 return (x << 8) | (x >> 24);
22 }
23
24 __owur static ossl_inline uint32_t rotr8(uint32_t x)
25 {
26 return (x >> 8) | (x << 24);
27 }
28
29 __owur static ossl_inline uint64_t byteswap8(uint64_t x)
30 {
31 uint32_t high = (uint32_t)(x >> 32);
32 uint32_t low = (uint32_t)x;
33
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;
37 }
38
39 __owur static ossl_inline uint64_t siv128_getword(SIV_BLOCK const *b, size_t i)
40 {
41 const union {
42 long one;
43 char little;
44 } is_endian = { 1 };
45
46 if (is_endian.little)
47 return byteswap8(b->word[i]);
48 return b->word[i];
49 }
50
51 static ossl_inline void siv128_putword(SIV_BLOCK *b, size_t i, uint64_t x)
52 {
53 const union {
54 long one;
55 char little;
56 } is_endian = { 1 };
57
58 if (is_endian.little)
59 b->word[i] = byteswap8(x);
60 else
61 b->word[i] = x;
62 }
63
64 static ossl_inline void siv128_xorblock(SIV_BLOCK *x,
65 SIV_BLOCK const *y)
66 {
67 x->word[0] ^= y->word[0];
68 x->word[1] ^= y->word[1];
69 }
70
71 /*
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
76 */
77 static ossl_inline void siv128_dbl(SIV_BLOCK *b)
78 {
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;
85
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);
90 }
91
92 __owur static ossl_inline int siv128_do_s2v_p(SIV128_CONTEXT *ctx, SIV_BLOCK *out,
93 unsigned char const* in, size_t len)
94 {
95 SIV_BLOCK t;
96 size_t out_len = sizeof(out->byte);
97 EVP_MAC_CTX *mac_ctx;
98 int ret = 0;
99
100 mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init);
101 if (mac_ctx == NULL)
102 return 0;
103
104 if (len >= SIV_LEN) {
105 if (!EVP_MAC_update(mac_ctx, in, len - SIV_LEN))
106 goto err;
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))
110 goto err;
111 } else {
112 memset(&t, 0, sizeof(t));
113 memcpy(&t, in, len);
114 t.byte[len] = 0x80;
115 siv128_dbl(&ctx->d);
116 siv128_xorblock(&t, &ctx->d);
117 if (!EVP_MAC_update(mac_ctx, t.byte, SIV_LEN))
118 goto err;
119 }
120 if (!EVP_MAC_final(mac_ctx, out->byte, &out_len)
121 || out_len != SIV_LEN)
122 goto err;
123
124 ret = 1;
125
126 err:
127 EVP_MAC_CTX_free(mac_ctx);
128 return ret;
129 }
130
131
132 __owur static ossl_inline int siv128_do_encrypt(EVP_CIPHER_CTX *ctx, unsigned char *out,
133 unsigned char const *in, size_t len,
134 SIV_BLOCK *icv)
135 {
136 int out_len = (int)len;
137
138 if (!EVP_CipherInit_ex(ctx, NULL, NULL, NULL, icv->byte, 1))
139 return 0;
140 return EVP_EncryptUpdate(ctx, out, &out_len, in, out_len);
141 }
142
143 /*
144 * Create a new SIV128_CONTEXT
145 */
146 SIV128_CONTEXT *CRYPTO_siv128_new(const unsigned char *key, int klen, EVP_CIPHER* cbc, EVP_CIPHER* ctr)
147 {
148 SIV128_CONTEXT *ctx;
149 int ret;
150
151 if ((ctx = OPENSSL_malloc(sizeof(*ctx))) != NULL) {
152 ret = CRYPTO_siv128_init(ctx, key, klen, cbc, ctr);
153 if (ret)
154 return ctx;
155 OPENSSL_free(ctx);
156 }
157
158 return NULL;
159 }
160
161 /*
162 * Initialise an existing SIV128_CONTEXT
163 */
164 int CRYPTO_siv128_init(SIV128_CONTEXT *ctx, const unsigned char *key, int klen,
165 const EVP_CIPHER* cbc, const EVP_CIPHER* ctr)
166 {
167 static const unsigned char zero[SIV_LEN] = { 0 };
168 size_t out_len = SIV_LEN;
169 EVP_MAC_CTX *mac_ctx = NULL;
170
171 memset(&ctx->d, 0, sizeof(ctx->d));
172 ctx->cipher_ctx = NULL;
173 ctx->mac_ctx_init = NULL;
174
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);
187 return 0;
188 }
189 EVP_MAC_CTX_free(mac_ctx);
190
191 ctx->final_ret = -1;
192 ctx->crypto_ok = 1;
193
194 return 1;
195 }
196
197 /*
198 * Copy an SIV128_CONTEXT object
199 */
200 int CRYPTO_siv128_copy_ctx(SIV128_CONTEXT *dest, SIV128_CONTEXT *src)
201 {
202 memcpy(&dest->d, &src->d, sizeof(src->d));
203 if (!EVP_CIPHER_CTX_copy(dest->cipher_ctx, src->cipher_ctx))
204 return 0;
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)
208 return 0;
209 return 1;
210 }
211
212 /*
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
216 */
217 int CRYPTO_siv128_aad(SIV128_CONTEXT *ctx, const unsigned char *aad,
218 size_t len)
219 {
220 SIV_BLOCK mac_out;
221 size_t out_len = SIV_LEN;
222 EVP_MAC_CTX *mac_ctx;
223
224 siv128_dbl(&ctx->d);
225
226 mac_ctx = EVP_MAC_CTX_dup(ctx->mac_ctx_init);
227 if (mac_ctx == NULL
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);
232 return 0;
233 }
234 EVP_MAC_CTX_free(mac_ctx);
235
236 siv128_xorblock(&ctx->d, &mac_out);
237
238 return 1;
239 }
240
241 /*
242 * Provide any data to be encrypted. This can be called once.
243 */
244 int CRYPTO_siv128_encrypt(SIV128_CONTEXT *ctx,
245 const unsigned char *in, unsigned char *out,
246 size_t len)
247 {
248 SIV_BLOCK q;
249
250 /* can only do one crypto operation */
251 if (ctx->crypto_ok == 0)
252 return 0;
253 ctx->crypto_ok--;
254
255 if (!siv128_do_s2v_p(ctx, &q, in, len))
256 return 0;
257
258 memcpy(ctx->tag.byte, &q, SIV_LEN);
259 q.byte[8] &= 0x7f;
260 q.byte[12] &= 0x7f;
261
262 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q))
263 return 0;
264 ctx->final_ret = 0;
265 return len;
266 }
267
268 /*
269 * Provide any data to be decrypted. This can be called once.
270 */
271 int CRYPTO_siv128_decrypt(SIV128_CONTEXT *ctx,
272 const unsigned char *in, unsigned char *out,
273 size_t len)
274 {
275 unsigned char* p;
276 SIV_BLOCK t, q;
277 int i;
278
279 /* can only do one crypto operation */
280 if (ctx->crypto_ok == 0)
281 return 0;
282 ctx->crypto_ok--;
283
284 memcpy(&q, ctx->tag.byte, SIV_LEN);
285 q.byte[8] &= 0x7f;
286 q.byte[12] &= 0x7f;
287
288 if (!siv128_do_encrypt(ctx->cipher_ctx, out, in, len, &q)
289 || !siv128_do_s2v_p(ctx, &t, out, len))
290 return 0;
291
292 p = ctx->tag.byte;
293 for (i = 0; i < SIV_LEN; i++)
294 t.byte[i] ^= p[i];
295
296 if ((t.word[0] | t.word[1]) != 0) {
297 OPENSSL_cleanse(out, len);
298 return 0;
299 }
300 ctx->final_ret = 0;
301 return len;
302 }
303
304 /*
305 * Return the already calculated final result.
306 */
307 int CRYPTO_siv128_finish(SIV128_CONTEXT *ctx)
308 {
309 return ctx->final_ret;
310 }
311
312 /*
313 * Set the tag
314 */
315 int CRYPTO_siv128_set_tag(SIV128_CONTEXT *ctx, const unsigned char *tag, size_t len)
316 {
317 if (len != SIV_LEN)
318 return 0;
319
320 /* Copy the tag from the supplied buffer */
321 memcpy(ctx->tag.byte, tag, len);
322 return 1;
323 }
324
325 /*
326 * Retrieve the calculated tag
327 */
328 int CRYPTO_siv128_get_tag(SIV128_CONTEXT *ctx, unsigned char *tag, size_t len)
329 {
330 if (len != SIV_LEN)
331 return 0;
332
333 /* Copy the tag into the supplied buffer */
334 memcpy(tag, ctx->tag.byte, len);
335 return 1;
336 }
337
338 /*
339 * Release all resources
340 */
341 int CRYPTO_siv128_cleanup(SIV128_CONTEXT *ctx)
342 {
343 if (ctx != NULL) {
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));
350 ctx->final_ret = -1;
351 ctx->crypto_ok = 1;
352 }
353 return 1;
354 }
355
356 int CRYPTO_siv128_speed(SIV128_CONTEXT *ctx, int arg)
357 {
358 ctx->crypto_ok = (arg == 1) ? -1 : 1;
359 return 1;
360 }
361
362 #endif /* OPENSSL_NO_SIV */