]>
Commit | Line | Data |
---|---|---|
62867571 | 1 | /* |
39147079 | 2 | * Copyright 2015-2019 The OpenSSL Project Authors. All Rights Reserved. |
bd989745 | 3 | * |
4a8b0c55 | 4 | * Licensed under the Apache License 2.0 (the "License"). You may not use |
62867571 RS |
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 | |
bd989745 AP |
8 | */ |
9 | ||
10 | #include <stdio.h> | |
11 | #include "internal/cryptlib.h" | |
12 | ||
13 | #ifndef OPENSSL_NO_CHACHA | |
14 | ||
15 | # include <openssl/evp.h> | |
16 | # include <openssl/objects.h> | |
25f2138b | 17 | # include "crypto/evp.h" |
5a285add | 18 | # include "evp_locl.h" |
25f2138b | 19 | # include "crypto/chacha.h" |
bd989745 AP |
20 | |
21 | typedef struct { | |
22 | union { | |
39147079 | 23 | OSSL_UNION_ALIGN; /* this ensures even sizeof(EVP_CHACHA_KEY)%8==0 */ |
bd989745 AP |
24 | unsigned int d[CHACHA_KEY_SIZE / 4]; |
25 | } key; | |
26 | unsigned int counter[CHACHA_CTR_SIZE / 4]; | |
27 | unsigned char buf[CHACHA_BLK_SIZE]; | |
28 | unsigned int partial_len; | |
29 | } EVP_CHACHA_KEY; | |
30 | ||
31 | #define data(ctx) ((EVP_CHACHA_KEY *)(ctx)->cipher_data) | |
32 | ||
2a3d0ee9 MC |
33 | #define CHACHA20_POLY1305_MAX_IVLEN 12 |
34 | ||
bd989745 AP |
35 | static int chacha_init_key(EVP_CIPHER_CTX *ctx, |
36 | const unsigned char user_key[CHACHA_KEY_SIZE], | |
37 | const unsigned char iv[CHACHA_CTR_SIZE], int enc) | |
38 | { | |
39 | EVP_CHACHA_KEY *key = data(ctx); | |
40 | unsigned int i; | |
41 | ||
42 | if (user_key) | |
43 | for (i = 0; i < CHACHA_KEY_SIZE; i+=4) { | |
44 | key->key.d[i/4] = CHACHA_U8TOU32(user_key+i); | |
45 | } | |
46 | ||
47 | if (iv) | |
48 | for (i = 0; i < CHACHA_CTR_SIZE; i+=4) { | |
49 | key->counter[i/4] = CHACHA_U8TOU32(iv+i); | |
50 | } | |
51 | ||
52 | key->partial_len = 0; | |
53 | ||
54 | return 1; | |
55 | } | |
56 | ||
57 | static int chacha_cipher(EVP_CIPHER_CTX * ctx, unsigned char *out, | |
58 | const unsigned char *inp, size_t len) | |
59 | { | |
60 | EVP_CHACHA_KEY *key = data(ctx); | |
61 | unsigned int n, rem, ctr32; | |
62 | ||
63 | if ((n = key->partial_len)) { | |
64 | while (len && n < CHACHA_BLK_SIZE) { | |
65 | *out++ = *inp++ ^ key->buf[n++]; | |
66 | len--; | |
67 | } | |
68 | key->partial_len = n; | |
69 | ||
70 | if (len == 0) | |
71 | return 1; | |
72 | ||
73 | if (n == CHACHA_BLK_SIZE) { | |
74 | key->partial_len = 0; | |
75 | key->counter[0]++; | |
76 | if (key->counter[0] == 0) | |
77 | key->counter[1]++; | |
78 | } | |
79 | } | |
80 | ||
81 | rem = (unsigned int)(len % CHACHA_BLK_SIZE); | |
82 | len -= rem; | |
83 | ctr32 = key->counter[0]; | |
84 | while (len >= CHACHA_BLK_SIZE) { | |
85 | size_t blocks = len / CHACHA_BLK_SIZE; | |
86 | /* | |
87 | * 1<<28 is just a not-so-small yet not-so-large number... | |
88 | * Below condition is practically never met, but it has to | |
89 | * be checked for code correctness. | |
90 | */ | |
91 | if (sizeof(size_t)>sizeof(unsigned int) && blocks>(1U<<28)) | |
92 | blocks = (1U<<28); | |
93 | ||
94 | /* | |
95 | * As ChaCha20_ctr32 operates on 32-bit counter, caller | |
96 | * has to handle overflow. 'if' below detects the | |
97 | * overflow, which is then handled by limiting the | |
98 | * amount of blocks to the exact overflow point... | |
99 | */ | |
100 | ctr32 += (unsigned int)blocks; | |
101 | if (ctr32 < blocks) { | |
102 | blocks -= ctr32; | |
103 | ctr32 = 0; | |
104 | } | |
105 | blocks *= CHACHA_BLK_SIZE; | |
106 | ChaCha20_ctr32(out, inp, blocks, key->key.d, key->counter); | |
107 | len -= blocks; | |
108 | inp += blocks; | |
109 | out += blocks; | |
110 | ||
111 | key->counter[0] = ctr32; | |
112 | if (ctr32 == 0) key->counter[1]++; | |
113 | } | |
114 | ||
115 | if (rem) { | |
116 | memset(key->buf, 0, sizeof(key->buf)); | |
117 | ChaCha20_ctr32(key->buf, key->buf, CHACHA_BLK_SIZE, | |
118 | key->key.d, key->counter); | |
119 | for (n = 0; n < rem; n++) | |
120 | out[n] = inp[n] ^ key->buf[n]; | |
121 | key->partial_len = rem; | |
122 | } | |
123 | ||
124 | return 1; | |
125 | } | |
126 | ||
127 | static const EVP_CIPHER chacha20 = { | |
128 | NID_chacha20, | |
129 | 1, /* block_size */ | |
130 | CHACHA_KEY_SIZE, /* key_len */ | |
131 | CHACHA_CTR_SIZE, /* iv_len, 128-bit counter in the context */ | |
c83680a0 | 132 | EVP_CIPH_CUSTOM_IV | EVP_CIPH_ALWAYS_CALL_INIT, |
bd989745 AP |
133 | chacha_init_key, |
134 | chacha_cipher, | |
135 | NULL, | |
136 | sizeof(EVP_CHACHA_KEY), | |
137 | NULL, | |
138 | NULL, | |
139 | NULL, | |
140 | NULL | |
141 | }; | |
142 | ||
143 | const EVP_CIPHER *EVP_chacha20(void) | |
144 | { | |
26a7d938 | 145 | return &chacha20; |
bd989745 AP |
146 | } |
147 | ||
148 | # ifndef OPENSSL_NO_POLY1305 | |
25f2138b | 149 | # include "crypto/poly1305.h" |
bd989745 AP |
150 | |
151 | typedef struct { | |
152 | EVP_CHACHA_KEY key; | |
153 | unsigned int nonce[12/4]; | |
154 | unsigned char tag[POLY1305_BLOCK_SIZE]; | |
a091e212 | 155 | unsigned char tls_aad[POLY1305_BLOCK_SIZE]; |
bd989745 AP |
156 | struct { uint64_t aad, text; } len; |
157 | int aad, mac_inited, tag_len, nonce_len; | |
158 | size_t tls_payload_length; | |
159 | } EVP_CHACHA_AEAD_CTX; | |
160 | ||
161 | # define NO_TLS_PAYLOAD_LENGTH ((size_t)-1) | |
162 | # define aead_data(ctx) ((EVP_CHACHA_AEAD_CTX *)(ctx)->cipher_data) | |
163 | # define POLY1305_ctx(actx) ((POLY1305 *)(actx + 1)) | |
164 | ||
165 | static int chacha20_poly1305_init_key(EVP_CIPHER_CTX *ctx, | |
166 | const unsigned char *inkey, | |
167 | const unsigned char *iv, int enc) | |
168 | { | |
169 | EVP_CHACHA_AEAD_CTX *actx = aead_data(ctx); | |
bd989745 AP |
170 | |
171 | if (!inkey && !iv) | |
172 | return 1; | |
173 | ||
174 | actx->len.aad = 0; | |
175 | actx->len.text = 0; | |
176 | actx->aad = 0; | |
177 | actx->mac_inited = 0; | |
178 | actx->tls_payload_length = NO_TLS_PAYLOAD_LENGTH; | |
179 | ||
d2dfd482 KY |
180 | if (iv != NULL) { |
181 | unsigned char temp[CHACHA_CTR_SIZE] = { 0 }; | |
bd989745 | 182 | |
d2dfd482 KY |
183 | /* pad on the left */ |
184 | if (actx->nonce_len <= CHACHA_CTR_SIZE) | |
a091e212 AP |
185 | memcpy(temp + CHACHA_CTR_SIZE - actx->nonce_len, iv, |
186 | actx->nonce_len); | |
bd989745 | 187 | |
d2dfd482 KY |
188 | chacha_init_key(ctx, inkey, temp, enc); |
189 | ||
190 | actx->nonce[0] = actx->key.counter[1]; | |
191 | actx->nonce[1] = actx->key.counter[2]; | |
192 | actx->nonce[2] = actx->key.counter[3]; | |
193 | } else { | |
194 | chacha_init_key(ctx, inkey, NULL, enc); | |
195 | } | |
bd989745 AP |
196 | |
197 | return 1; | |
198 | } | |
199 | ||
a091e212 | 200 | # if !defined(OPENSSL_SMALL_FOOTPRINT) |
0edb109f AP |
201 | |
202 | # if defined(POLY1305_ASM) && (defined(__x86_64) || defined(__x86_64__) || \ | |
203 | defined(_M_AMD64) || defined(_M_X64)) | |
204 | # define XOR128_HELPERS | |
205 | void *xor128_encrypt_n_pad(void *out, const void *inp, void *otp, size_t len); | |
206 | void *xor128_decrypt_n_pad(void *out, const void *inp, void *otp, size_t len); | |
207 | static const unsigned char zero[4 * CHACHA_BLK_SIZE] = { 0 }; | |
208 | # else | |
a091e212 | 209 | static const unsigned char zero[2 * CHACHA_BLK_SIZE] = { 0 }; |
0edb109f | 210 | # endif |
a091e212 AP |
211 | |
212 | static int chacha20_poly1305_tls_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, | |
213 | const unsigned char *in, size_t len) | |
214 | { | |
215 | EVP_CHACHA_AEAD_CTX *actx = aead_data(ctx); | |
0edb109f AP |
216 | size_t tail, tohash_len, buf_len, plen = actx->tls_payload_length; |
217 | unsigned char *buf, *tohash, *ctr, storage[sizeof(zero) + 32]; | |
a091e212 AP |
218 | |
219 | if (len != plen + POLY1305_BLOCK_SIZE) | |
220 | return -1; | |
221 | ||
222 | buf = storage + ((0 - (size_t)storage) & 15); /* align */ | |
223 | ctr = buf + CHACHA_BLK_SIZE; | |
224 | tohash = buf + CHACHA_BLK_SIZE - POLY1305_BLOCK_SIZE; | |
225 | ||
0edb109f AP |
226 | # ifdef XOR128_HELPERS |
227 | if (plen <= 3 * CHACHA_BLK_SIZE) { | |
a091e212 | 228 | actx->key.counter[0] = 0; |
0edb109f AP |
229 | buf_len = (plen + 2 * CHACHA_BLK_SIZE - 1) & (0 - CHACHA_BLK_SIZE); |
230 | ChaCha20_ctr32(buf, zero, buf_len, actx->key.key.d, | |
a091e212 AP |
231 | actx->key.counter); |
232 | Poly1305_Init(POLY1305_ctx(actx), buf); | |
233 | actx->key.partial_len = 0; | |
234 | memcpy(tohash, actx->tls_aad, POLY1305_BLOCK_SIZE); | |
235 | tohash_len = POLY1305_BLOCK_SIZE; | |
236 | actx->len.aad = EVP_AEAD_TLS1_AAD_LEN; | |
237 | actx->len.text = plen; | |
238 | ||
0edb109f AP |
239 | if (plen) { |
240 | if (ctx->encrypt) | |
241 | ctr = xor128_encrypt_n_pad(out, in, ctr, plen); | |
242 | else | |
243 | ctr = xor128_decrypt_n_pad(out, in, ctr, plen); | |
244 | ||
245 | in += plen; | |
246 | out += plen; | |
247 | tohash_len = (size_t)(ctr - tohash); | |
248 | } | |
249 | } | |
250 | # else | |
251 | if (plen <= CHACHA_BLK_SIZE) { | |
252 | size_t i; | |
253 | ||
254 | actx->key.counter[0] = 0; | |
255 | ChaCha20_ctr32(buf, zero, (buf_len = 2 * CHACHA_BLK_SIZE), | |
256 | actx->key.key.d, actx->key.counter); | |
257 | Poly1305_Init(POLY1305_ctx(actx), buf); | |
258 | actx->key.partial_len = 0; | |
259 | memcpy(tohash, actx->tls_aad, POLY1305_BLOCK_SIZE); | |
260 | tohash_len = POLY1305_BLOCK_SIZE; | |
261 | actx->len.aad = EVP_AEAD_TLS1_AAD_LEN; | |
262 | actx->len.text = plen; | |
263 | ||
a091e212 AP |
264 | if (ctx->encrypt) { |
265 | for (i = 0; i < plen; i++) { | |
266 | out[i] = ctr[i] ^= in[i]; | |
267 | } | |
268 | } else { | |
269 | for (i = 0; i < plen; i++) { | |
270 | unsigned char c = in[i]; | |
271 | out[i] = ctr[i] ^ c; | |
272 | ctr[i] = c; | |
273 | } | |
274 | } | |
275 | ||
276 | in += i; | |
277 | out += i; | |
278 | ||
279 | tail = (0 - i) & (POLY1305_BLOCK_SIZE - 1); | |
280 | memset(ctr + i, 0, tail); | |
281 | ctr += i + tail; | |
282 | tohash_len += i + tail; | |
0edb109f AP |
283 | } |
284 | # endif | |
285 | else { | |
a091e212 | 286 | actx->key.counter[0] = 0; |
0edb109f AP |
287 | ChaCha20_ctr32(buf, zero, (buf_len = CHACHA_BLK_SIZE), |
288 | actx->key.key.d, actx->key.counter); | |
a091e212 AP |
289 | Poly1305_Init(POLY1305_ctx(actx), buf); |
290 | actx->key.counter[0] = 1; | |
291 | actx->key.partial_len = 0; | |
292 | Poly1305_Update(POLY1305_ctx(actx), actx->tls_aad, POLY1305_BLOCK_SIZE); | |
293 | tohash = ctr; | |
294 | tohash_len = 0; | |
295 | actx->len.aad = EVP_AEAD_TLS1_AAD_LEN; | |
296 | actx->len.text = plen; | |
297 | ||
298 | if (ctx->encrypt) { | |
299 | ChaCha20_ctr32(out, in, plen, actx->key.key.d, actx->key.counter); | |
300 | Poly1305_Update(POLY1305_ctx(actx), out, plen); | |
301 | } else { | |
302 | Poly1305_Update(POLY1305_ctx(actx), in, plen); | |
303 | ChaCha20_ctr32(out, in, plen, actx->key.key.d, actx->key.counter); | |
304 | } | |
305 | ||
306 | in += plen; | |
307 | out += plen; | |
308 | tail = (0 - plen) & (POLY1305_BLOCK_SIZE - 1); | |
309 | Poly1305_Update(POLY1305_ctx(actx), zero, tail); | |
310 | } | |
311 | ||
312 | { | |
313 | const union { | |
314 | long one; | |
315 | char little; | |
316 | } is_endian = { 1 }; | |
317 | ||
318 | if (is_endian.little) { | |
319 | memcpy(ctr, (unsigned char *)&actx->len, POLY1305_BLOCK_SIZE); | |
320 | } else { | |
321 | ctr[0] = (unsigned char)(actx->len.aad); | |
322 | ctr[1] = (unsigned char)(actx->len.aad>>8); | |
323 | ctr[2] = (unsigned char)(actx->len.aad>>16); | |
324 | ctr[3] = (unsigned char)(actx->len.aad>>24); | |
325 | ctr[4] = (unsigned char)(actx->len.aad>>32); | |
326 | ctr[5] = (unsigned char)(actx->len.aad>>40); | |
327 | ctr[6] = (unsigned char)(actx->len.aad>>48); | |
328 | ctr[7] = (unsigned char)(actx->len.aad>>56); | |
329 | ||
330 | ctr[8] = (unsigned char)(actx->len.text); | |
331 | ctr[9] = (unsigned char)(actx->len.text>>8); | |
332 | ctr[10] = (unsigned char)(actx->len.text>>16); | |
333 | ctr[11] = (unsigned char)(actx->len.text>>24); | |
334 | ctr[12] = (unsigned char)(actx->len.text>>32); | |
335 | ctr[13] = (unsigned char)(actx->len.text>>40); | |
336 | ctr[14] = (unsigned char)(actx->len.text>>48); | |
337 | ctr[15] = (unsigned char)(actx->len.text>>56); | |
338 | } | |
339 | tohash_len += POLY1305_BLOCK_SIZE; | |
340 | } | |
341 | ||
342 | Poly1305_Update(POLY1305_ctx(actx), tohash, tohash_len); | |
0edb109f | 343 | OPENSSL_cleanse(buf, buf_len); |
a091e212 AP |
344 | Poly1305_Final(POLY1305_ctx(actx), ctx->encrypt ? actx->tag |
345 | : tohash); | |
346 | ||
347 | actx->tls_payload_length = NO_TLS_PAYLOAD_LENGTH; | |
348 | ||
349 | if (ctx->encrypt) { | |
350 | memcpy(out, actx->tag, POLY1305_BLOCK_SIZE); | |
351 | } else { | |
352 | if (CRYPTO_memcmp(tohash, in, POLY1305_BLOCK_SIZE)) { | |
353 | memset(out - (len - POLY1305_BLOCK_SIZE), 0, | |
354 | len - POLY1305_BLOCK_SIZE); | |
355 | return -1; | |
356 | } | |
357 | } | |
358 | ||
359 | return len; | |
360 | } | |
361 | # else | |
362 | static const unsigned char zero[CHACHA_BLK_SIZE] = { 0 }; | |
363 | # endif | |
364 | ||
bd989745 AP |
365 | static int chacha20_poly1305_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, |
366 | const unsigned char *in, size_t len) | |
367 | { | |
368 | EVP_CHACHA_AEAD_CTX *actx = aead_data(ctx); | |
369 | size_t rem, plen = actx->tls_payload_length; | |
bd989745 AP |
370 | |
371 | if (!actx->mac_inited) { | |
a091e212 AP |
372 | # if !defined(OPENSSL_SMALL_FOOTPRINT) |
373 | if (plen != NO_TLS_PAYLOAD_LENGTH && out != NULL) | |
374 | return chacha20_poly1305_tls_cipher(ctx, out, in, len); | |
375 | # endif | |
bd989745 | 376 | actx->key.counter[0] = 0; |
a091e212 | 377 | ChaCha20_ctr32(actx->key.buf, zero, CHACHA_BLK_SIZE, |
bd989745 AP |
378 | actx->key.key.d, actx->key.counter); |
379 | Poly1305_Init(POLY1305_ctx(actx), actx->key.buf); | |
380 | actx->key.counter[0] = 1; | |
30a5f322 AP |
381 | actx->key.partial_len = 0; |
382 | actx->len.aad = actx->len.text = 0; | |
bd989745 | 383 | actx->mac_inited = 1; |
a091e212 AP |
384 | if (plen != NO_TLS_PAYLOAD_LENGTH) { |
385 | Poly1305_Update(POLY1305_ctx(actx), actx->tls_aad, | |
386 | EVP_AEAD_TLS1_AAD_LEN); | |
387 | actx->len.aad = EVP_AEAD_TLS1_AAD_LEN; | |
388 | actx->aad = 1; | |
389 | } | |
bd989745 AP |
390 | } |
391 | ||
392 | if (in) { /* aad or text */ | |
393 | if (out == NULL) { /* aad */ | |
394 | Poly1305_Update(POLY1305_ctx(actx), in, len); | |
395 | actx->len.aad += len; | |
396 | actx->aad = 1; | |
397 | return len; | |
398 | } else { /* plain- or ciphertext */ | |
399 | if (actx->aad) { /* wrap up aad */ | |
400 | if ((rem = (size_t)actx->len.aad % POLY1305_BLOCK_SIZE)) | |
401 | Poly1305_Update(POLY1305_ctx(actx), zero, | |
402 | POLY1305_BLOCK_SIZE - rem); | |
403 | actx->aad = 0; | |
404 | } | |
405 | ||
406 | actx->tls_payload_length = NO_TLS_PAYLOAD_LENGTH; | |
407 | if (plen == NO_TLS_PAYLOAD_LENGTH) | |
408 | plen = len; | |
409 | else if (len != plen + POLY1305_BLOCK_SIZE) | |
410 | return -1; | |
411 | ||
412 | if (ctx->encrypt) { /* plaintext */ | |
413 | chacha_cipher(ctx, out, in, plen); | |
414 | Poly1305_Update(POLY1305_ctx(actx), out, plen); | |
415 | in += plen; | |
416 | out += plen; | |
417 | actx->len.text += plen; | |
418 | } else { /* ciphertext */ | |
419 | Poly1305_Update(POLY1305_ctx(actx), in, plen); | |
420 | chacha_cipher(ctx, out, in, plen); | |
421 | in += plen; | |
422 | out += plen; | |
423 | actx->len.text += plen; | |
424 | } | |
425 | } | |
426 | } | |
427 | if (in == NULL /* explicit final */ | |
428 | || plen != len) { /* or tls mode */ | |
429 | const union { | |
430 | long one; | |
431 | char little; | |
432 | } is_endian = { 1 }; | |
433 | unsigned char temp[POLY1305_BLOCK_SIZE]; | |
434 | ||
435 | if (actx->aad) { /* wrap up aad */ | |
436 | if ((rem = (size_t)actx->len.aad % POLY1305_BLOCK_SIZE)) | |
437 | Poly1305_Update(POLY1305_ctx(actx), zero, | |
438 | POLY1305_BLOCK_SIZE - rem); | |
439 | actx->aad = 0; | |
440 | } | |
441 | ||
442 | if ((rem = (size_t)actx->len.text % POLY1305_BLOCK_SIZE)) | |
443 | Poly1305_Update(POLY1305_ctx(actx), zero, | |
444 | POLY1305_BLOCK_SIZE - rem); | |
445 | ||
446 | if (is_endian.little) { | |
447 | Poly1305_Update(POLY1305_ctx(actx), | |
448 | (unsigned char *)&actx->len, POLY1305_BLOCK_SIZE); | |
449 | } else { | |
450 | temp[0] = (unsigned char)(actx->len.aad); | |
451 | temp[1] = (unsigned char)(actx->len.aad>>8); | |
452 | temp[2] = (unsigned char)(actx->len.aad>>16); | |
453 | temp[3] = (unsigned char)(actx->len.aad>>24); | |
454 | temp[4] = (unsigned char)(actx->len.aad>>32); | |
455 | temp[5] = (unsigned char)(actx->len.aad>>40); | |
456 | temp[6] = (unsigned char)(actx->len.aad>>48); | |
457 | temp[7] = (unsigned char)(actx->len.aad>>56); | |
458 | ||
459 | temp[8] = (unsigned char)(actx->len.text); | |
460 | temp[9] = (unsigned char)(actx->len.text>>8); | |
461 | temp[10] = (unsigned char)(actx->len.text>>16); | |
462 | temp[11] = (unsigned char)(actx->len.text>>24); | |
463 | temp[12] = (unsigned char)(actx->len.text>>32); | |
464 | temp[13] = (unsigned char)(actx->len.text>>40); | |
465 | temp[14] = (unsigned char)(actx->len.text>>48); | |
466 | temp[15] = (unsigned char)(actx->len.text>>56); | |
467 | ||
468 | Poly1305_Update(POLY1305_ctx(actx), temp, POLY1305_BLOCK_SIZE); | |
469 | } | |
470 | Poly1305_Final(POLY1305_ctx(actx), ctx->encrypt ? actx->tag | |
471 | : temp); | |
472 | actx->mac_inited = 0; | |
473 | ||
474 | if (in != NULL && len != plen) { /* tls mode */ | |
475 | if (ctx->encrypt) { | |
476 | memcpy(out, actx->tag, POLY1305_BLOCK_SIZE); | |
477 | } else { | |
478 | if (CRYPTO_memcmp(temp, in, POLY1305_BLOCK_SIZE)) { | |
bf52165b | 479 | memset(out - plen, 0, plen); |
bd989745 AP |
480 | return -1; |
481 | } | |
482 | } | |
483 | } | |
484 | else if (!ctx->encrypt) { | |
485 | if (CRYPTO_memcmp(temp, actx->tag, actx->tag_len)) | |
486 | return -1; | |
487 | } | |
488 | } | |
489 | return len; | |
490 | } | |
491 | ||
492 | static int chacha20_poly1305_cleanup(EVP_CIPHER_CTX *ctx) | |
493 | { | |
494 | EVP_CHACHA_AEAD_CTX *actx = aead_data(ctx); | |
495 | if (actx) | |
a8f95768 | 496 | OPENSSL_cleanse(ctx->cipher_data, sizeof(*actx) + Poly1305_ctx_size()); |
bd989745 AP |
497 | return 1; |
498 | } | |
499 | ||
500 | static int chacha20_poly1305_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, | |
501 | void *ptr) | |
502 | { | |
503 | EVP_CHACHA_AEAD_CTX *actx = aead_data(ctx); | |
504 | ||
505 | switch(type) { | |
506 | case EVP_CTRL_INIT: | |
507 | if (actx == NULL) | |
508 | actx = ctx->cipher_data | |
509 | = OPENSSL_zalloc(sizeof(*actx) + Poly1305_ctx_size()); | |
510 | if (actx == NULL) { | |
511 | EVPerr(EVP_F_CHACHA20_POLY1305_CTRL, EVP_R_INITIALIZATION_ERROR); | |
512 | return 0; | |
513 | } | |
514 | actx->len.aad = 0; | |
515 | actx->len.text = 0; | |
516 | actx->aad = 0; | |
517 | actx->mac_inited = 0; | |
518 | actx->tag_len = 0; | |
519 | actx->nonce_len = 12; | |
520 | actx->tls_payload_length = NO_TLS_PAYLOAD_LENGTH; | |
a091e212 | 521 | memset(actx->tls_aad, 0, POLY1305_BLOCK_SIZE); |
bd989745 AP |
522 | return 1; |
523 | ||
524 | case EVP_CTRL_COPY: | |
525 | if (actx) { | |
700b8145 F |
526 | EVP_CIPHER_CTX *dst = (EVP_CIPHER_CTX *)ptr; |
527 | ||
528 | dst->cipher_data = | |
529 | OPENSSL_memdup(actx, sizeof(*actx) + Poly1305_ctx_size()); | |
530 | if (dst->cipher_data == NULL) { | |
bd989745 AP |
531 | EVPerr(EVP_F_CHACHA20_POLY1305_CTRL, EVP_R_COPY_ERROR); |
532 | return 0; | |
533 | } | |
534 | } | |
535 | return 1; | |
536 | ||
7dddf2fc SL |
537 | case EVP_CTRL_GET_IVLEN: |
538 | *(int *)ptr = actx->nonce_len; | |
539 | return 1; | |
540 | ||
bd989745 | 541 | case EVP_CTRL_AEAD_SET_IVLEN: |
2a3d0ee9 | 542 | if (arg <= 0 || arg > CHACHA20_POLY1305_MAX_IVLEN) |
bd989745 AP |
543 | return 0; |
544 | actx->nonce_len = arg; | |
545 | return 1; | |
546 | ||
547 | case EVP_CTRL_AEAD_SET_IV_FIXED: | |
548 | if (arg != 12) | |
549 | return 0; | |
550 | actx->nonce[0] = actx->key.counter[1] | |
551 | = CHACHA_U8TOU32((unsigned char *)ptr); | |
552 | actx->nonce[1] = actx->key.counter[2] | |
553 | = CHACHA_U8TOU32((unsigned char *)ptr+4); | |
554 | actx->nonce[2] = actx->key.counter[3] | |
555 | = CHACHA_U8TOU32((unsigned char *)ptr+8); | |
556 | return 1; | |
557 | ||
558 | case EVP_CTRL_AEAD_SET_TAG: | |
559 | if (arg <= 0 || arg > POLY1305_BLOCK_SIZE) | |
560 | return 0; | |
561 | if (ptr != NULL) { | |
562 | memcpy(actx->tag, ptr, arg); | |
563 | actx->tag_len = arg; | |
564 | } | |
565 | return 1; | |
566 | ||
567 | case EVP_CTRL_AEAD_GET_TAG: | |
568 | if (arg <= 0 || arg > POLY1305_BLOCK_SIZE || !ctx->encrypt) | |
569 | return 0; | |
570 | memcpy(ptr, actx->tag, arg); | |
571 | return 1; | |
572 | ||
573 | case EVP_CTRL_AEAD_TLS1_AAD: | |
574 | if (arg != EVP_AEAD_TLS1_AAD_LEN) | |
575 | return 0; | |
576 | { | |
577 | unsigned int len; | |
a091e212 | 578 | unsigned char *aad = ptr; |
bd989745 | 579 | |
a091e212 | 580 | memcpy(actx->tls_aad, ptr, EVP_AEAD_TLS1_AAD_LEN); |
30a5f322 AP |
581 | len = aad[EVP_AEAD_TLS1_AAD_LEN - 2] << 8 | |
582 | aad[EVP_AEAD_TLS1_AAD_LEN - 1]; | |
a091e212 | 583 | aad = actx->tls_aad; |
bd989745 | 584 | if (!ctx->encrypt) { |
2198b3a5 AP |
585 | if (len < POLY1305_BLOCK_SIZE) |
586 | return 0; | |
bd989745 | 587 | len -= POLY1305_BLOCK_SIZE; /* discount attached tag */ |
a091e212 AP |
588 | aad[EVP_AEAD_TLS1_AAD_LEN - 2] = (unsigned char)(len >> 8); |
589 | aad[EVP_AEAD_TLS1_AAD_LEN - 1] = (unsigned char)len; | |
bd989745 AP |
590 | } |
591 | actx->tls_payload_length = len; | |
592 | ||
593 | /* | |
2198b3a5 | 594 | * merge record sequence number as per RFC7905 |
bd989745 AP |
595 | */ |
596 | actx->key.counter[1] = actx->nonce[0]; | |
30a5f322 AP |
597 | actx->key.counter[2] = actx->nonce[1] ^ CHACHA_U8TOU32(aad); |
598 | actx->key.counter[3] = actx->nonce[2] ^ CHACHA_U8TOU32(aad+4); | |
bd989745 | 599 | actx->mac_inited = 0; |
a091e212 | 600 | |
bd989745 AP |
601 | return POLY1305_BLOCK_SIZE; /* tag length */ |
602 | } | |
603 | ||
604 | case EVP_CTRL_AEAD_SET_MAC_KEY: | |
605 | /* no-op */ | |
606 | return 1; | |
607 | ||
608 | default: | |
609 | return -1; | |
610 | } | |
611 | } | |
612 | ||
613 | static EVP_CIPHER chacha20_poly1305 = { | |
614 | NID_chacha20_poly1305, | |
615 | 1, /* block_size */ | |
616 | CHACHA_KEY_SIZE, /* key_len */ | |
617 | 12, /* iv_len, 96-bit nonce in the context */ | |
618 | EVP_CIPH_FLAG_AEAD_CIPHER | EVP_CIPH_CUSTOM_IV | | |
619 | EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CTRL_INIT | | |
7dddf2fc SL |
620 | EVP_CIPH_CUSTOM_COPY | EVP_CIPH_FLAG_CUSTOM_CIPHER | |
621 | EVP_CIPH_CUSTOM_IV_LENGTH, | |
bd989745 AP |
622 | chacha20_poly1305_init_key, |
623 | chacha20_poly1305_cipher, | |
624 | chacha20_poly1305_cleanup, | |
625 | 0, /* 0 moves context-specific structure allocation to ctrl */ | |
626 | NULL, /* set_asn1_parameters */ | |
627 | NULL, /* get_asn1_parameters */ | |
628 | chacha20_poly1305_ctrl, | |
629 | NULL /* app_data */ | |
630 | }; | |
631 | ||
632 | const EVP_CIPHER *EVP_chacha20_poly1305(void) | |
633 | { | |
634 | return(&chacha20_poly1305); | |
635 | } | |
636 | # endif | |
637 | #endif |