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a672a02a | 1 | /* |
4333b89f | 2 | * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved. |
a672a02a SL |
3 | * |
4 | * Licensed under the Apache License 2.0 (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 | ||
e1178600 SL |
10 | /* Dispatch functions for gcm mode */ |
11 | ||
2741128e TM |
12 | #include <openssl/rand.h> |
13 | #include <openssl/proverr.h> | |
604e884b | 14 | #include "prov/ciphercommon.h" |
68a51d59 | 15 | #include "prov/ciphercommon_gcm.h" |
f99d3eed | 16 | #include "prov/providercommon.h" |
ddd21319 | 17 | #include "prov/provider_ctx.h" |
a672a02a SL |
18 | |
19 | static int gcm_tls_init(PROV_GCM_CTX *dat, unsigned char *aad, size_t aad_len); | |
20 | static int gcm_tls_iv_set_fixed(PROV_GCM_CTX *ctx, unsigned char *iv, | |
21 | size_t len); | |
22 | static int gcm_tls_cipher(PROV_GCM_CTX *ctx, unsigned char *out, size_t *padlen, | |
23 | const unsigned char *in, size_t len); | |
24 | static int gcm_cipher_internal(PROV_GCM_CTX *ctx, unsigned char *out, | |
25 | size_t *padlen, const unsigned char *in, | |
26 | size_t len); | |
27 | ||
e1178600 SL |
28 | void gcm_initctx(void *provctx, PROV_GCM_CTX *ctx, size_t keybits, |
29 | const PROV_GCM_HW *hw, size_t ivlen_min) | |
a672a02a SL |
30 | { |
31 | ctx->pad = 1; | |
32 | ctx->mode = EVP_CIPH_GCM_MODE; | |
1c3ace68 SL |
33 | ctx->taglen = UNINITIALISED_SIZET; |
34 | ctx->tls_aad_len = UNINITIALISED_SIZET; | |
a672a02a SL |
35 | ctx->ivlen_min = ivlen_min; |
36 | ctx->ivlen = (EVP_GCM_TLS_FIXED_IV_LEN + EVP_GCM_TLS_EXPLICIT_IV_LEN); | |
37 | ctx->keylen = keybits / 8; | |
38 | ctx->hw = hw; | |
a829b735 | 39 | ctx->libctx = PROV_LIBCTX_OF(provctx); |
a672a02a SL |
40 | } |
41 | ||
a672a02a SL |
42 | static int gcm_init(void *vctx, const unsigned char *key, size_t keylen, |
43 | const unsigned char *iv, size_t ivlen, int enc) | |
44 | { | |
45 | PROV_GCM_CTX *ctx = (PROV_GCM_CTX *)vctx; | |
46 | ||
f99d3eed P |
47 | if (!ossl_prov_is_running()) |
48 | return 0; | |
49 | ||
a672a02a SL |
50 | ctx->enc = enc; |
51 | ||
52 | if (iv != NULL) { | |
53 | if (ivlen < ctx->ivlen_min || ivlen > sizeof(ctx->iv)) { | |
784883fc | 54 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); |
a672a02a SL |
55 | return 0; |
56 | } | |
57 | ctx->ivlen = ivlen; | |
089cb623 | 58 | memcpy(ctx->iv, iv, ivlen); |
a672a02a SL |
59 | ctx->iv_state = IV_STATE_BUFFERED; |
60 | } | |
61 | ||
62 | if (key != NULL) { | |
63 | if (keylen != ctx->keylen) { | |
784883fc | 64 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); |
a672a02a SL |
65 | return 0; |
66 | } | |
67 | return ctx->hw->setkey(ctx, key, ctx->keylen); | |
68 | } | |
69 | return 1; | |
70 | } | |
71 | ||
e1178600 SL |
72 | int gcm_einit(void *vctx, const unsigned char *key, size_t keylen, |
73 | const unsigned char *iv, size_t ivlen) | |
a672a02a SL |
74 | { |
75 | return gcm_init(vctx, key, keylen, iv, ivlen, 1); | |
76 | } | |
77 | ||
e1178600 SL |
78 | int gcm_dinit(void *vctx, const unsigned char *key, size_t keylen, |
79 | const unsigned char *iv, size_t ivlen) | |
a672a02a SL |
80 | { |
81 | return gcm_init(vctx, key, keylen, iv, ivlen, 0); | |
82 | } | |
83 | ||
11b44359 SL |
84 | /* increment counter (64-bit int) by 1 */ |
85 | static void ctr64_inc(unsigned char *counter) | |
86 | { | |
87 | int n = 8; | |
88 | unsigned char c; | |
89 | ||
90 | do { | |
91 | --n; | |
92 | c = counter[n]; | |
93 | ++c; | |
94 | counter[n] = c; | |
95 | if (c > 0) | |
96 | return; | |
97 | } while (n > 0); | |
98 | } | |
99 | ||
100 | static int getivgen(PROV_GCM_CTX *ctx, unsigned char *out, size_t olen) | |
101 | { | |
102 | if (!ctx->iv_gen | |
103 | || !ctx->key_set | |
104 | || !ctx->hw->setiv(ctx, ctx->iv, ctx->ivlen)) | |
105 | return 0; | |
106 | if (olen == 0 || olen > ctx->ivlen) | |
107 | olen = ctx->ivlen; | |
108 | memcpy(out, ctx->iv + ctx->ivlen - olen, olen); | |
109 | /* | |
110 | * Invocation field will be at least 8 bytes in size and so no need | |
111 | * to check wrap around or increment more than last 8 bytes. | |
112 | */ | |
113 | ctr64_inc(ctx->iv + ctx->ivlen - 8); | |
114 | ctx->iv_state = IV_STATE_COPIED; | |
115 | return 1; | |
116 | } | |
117 | ||
118 | static int setivinv(PROV_GCM_CTX *ctx, unsigned char *in, size_t inl) | |
119 | { | |
120 | if (!ctx->iv_gen | |
121 | || !ctx->key_set | |
122 | || ctx->enc) | |
123 | return 0; | |
124 | ||
125 | memcpy(ctx->iv + ctx->ivlen - inl, in, inl); | |
126 | if (!ctx->hw->setiv(ctx, ctx->iv, ctx->ivlen)) | |
127 | return 0; | |
128 | ctx->iv_state = IV_STATE_COPIED; | |
129 | return 1; | |
130 | } | |
131 | ||
e1178600 | 132 | int gcm_get_ctx_params(void *vctx, OSSL_PARAM params[]) |
a672a02a SL |
133 | { |
134 | PROV_GCM_CTX *ctx = (PROV_GCM_CTX *)vctx; | |
135 | OSSL_PARAM *p; | |
136 | size_t sz; | |
137 | ||
138 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_IVLEN); | |
1c3ace68 | 139 | if (p != NULL && !OSSL_PARAM_set_size_t(p, ctx->ivlen)) { |
3bfe9005 SL |
140 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); |
141 | return 0; | |
a672a02a SL |
142 | } |
143 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_KEYLEN); | |
1c3ace68 | 144 | if (p != NULL && !OSSL_PARAM_set_size_t(p, ctx->keylen)) { |
784883fc | 145 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); |
a672a02a SL |
146 | return 0; |
147 | } | |
dc64dc2e SL |
148 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TAGLEN); |
149 | if (p != NULL) { | |
150 | size_t taglen = (ctx->taglen != UNINITIALISED_SIZET) ? ctx->taglen : | |
151 | GCM_TAG_MAX_SIZE; | |
152 | ||
153 | if (!OSSL_PARAM_set_size_t(p, taglen)) { | |
154 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); | |
155 | return 0; | |
156 | } | |
157 | } | |
a672a02a SL |
158 | |
159 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_IV); | |
160 | if (p != NULL) { | |
ef58f9af | 161 | if (ctx->iv_state == IV_STATE_UNINITIALISED) |
a672a02a | 162 | return 0; |
7cc5e0d2 | 163 | if (ctx->ivlen > p->data_size) { |
784883fc | 164 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); |
a672a02a SL |
165 | return 0; |
166 | } | |
320d96a3 BK |
167 | if (!OSSL_PARAM_set_octet_string(p, ctx->iv, ctx->ivlen) |
168 | && !OSSL_PARAM_set_octet_ptr(p, &ctx->iv, ctx->ivlen)) { | |
784883fc | 169 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); |
a672a02a SL |
170 | return 0; |
171 | } | |
172 | } | |
173 | ||
0d83b7b9 | 174 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_UPDATED_IV); |
84890268 | 175 | if (p != NULL) { |
ef58f9af | 176 | if (ctx->iv_state == IV_STATE_UNINITIALISED) |
84890268 BK |
177 | return 0; |
178 | if (ctx->ivlen > p->data_size) { | |
179 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); | |
180 | return 0; | |
181 | } | |
182 | if (!OSSL_PARAM_set_octet_string(p, ctx->iv, ctx->ivlen) | |
183 | && !OSSL_PARAM_set_octet_ptr(p, &ctx->iv, ctx->ivlen)) { | |
184 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); | |
185 | return 0; | |
186 | } | |
187 | } | |
188 | ||
a672a02a SL |
189 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD); |
190 | if (p != NULL && !OSSL_PARAM_set_size_t(p, ctx->tls_aad_pad_sz)) { | |
784883fc | 191 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); |
a672a02a SL |
192 | return 0; |
193 | } | |
194 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TAG); | |
195 | if (p != NULL) { | |
196 | sz = p->data_size; | |
1c3ace68 SL |
197 | if (sz == 0 |
198 | || sz > EVP_GCM_TLS_TAG_LEN | |
199 | || !ctx->enc | |
200 | || ctx->taglen == UNINITIALISED_SIZET) { | |
784883fc | 201 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_TAG); |
a672a02a SL |
202 | return 0; |
203 | } | |
204 | if (!OSSL_PARAM_set_octet_string(p, ctx->buf, sz)) { | |
784883fc | 205 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_SET_PARAMETER); |
a672a02a SL |
206 | return 0; |
207 | } | |
208 | } | |
11b44359 SL |
209 | p = OSSL_PARAM_locate(params, OSSL_CIPHER_PARAM_AEAD_TLS1_GET_IV_GEN); |
210 | if (p != NULL) { | |
211 | if (p->data == NULL | |
212 | || p->data_type != OSSL_PARAM_OCTET_STRING | |
213 | || !getivgen(ctx, p->data, p->data_size)) | |
214 | return 0; | |
215 | } | |
a672a02a SL |
216 | return 1; |
217 | } | |
218 | ||
e1178600 | 219 | int gcm_set_ctx_params(void *vctx, const OSSL_PARAM params[]) |
a672a02a SL |
220 | { |
221 | PROV_GCM_CTX *ctx = (PROV_GCM_CTX *)vctx; | |
222 | const OSSL_PARAM *p; | |
223 | size_t sz; | |
224 | void *vp; | |
225 | ||
226 | p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TAG); | |
227 | if (p != NULL) { | |
228 | vp = ctx->buf; | |
229 | if (!OSSL_PARAM_get_octet_string(p, &vp, EVP_GCM_TLS_TAG_LEN, &sz)) { | |
784883fc | 230 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); |
a672a02a SL |
231 | return 0; |
232 | } | |
233 | if (sz == 0 || ctx->enc) { | |
784883fc | 234 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_TAG); |
a672a02a SL |
235 | return 0; |
236 | } | |
237 | ctx->taglen = sz; | |
238 | } | |
239 | ||
240 | p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_IVLEN); | |
241 | if (p != NULL) { | |
242 | if (!OSSL_PARAM_get_size_t(p, &sz)) { | |
784883fc | 243 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); |
a672a02a SL |
244 | return 0; |
245 | } | |
246 | if (sz == 0 || sz > sizeof(ctx->iv)) { | |
784883fc | 247 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_IV_LENGTH); |
a672a02a SL |
248 | return 0; |
249 | } | |
250 | ctx->ivlen = sz; | |
251 | } | |
252 | ||
253 | p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TLS1_AAD); | |
254 | if (p != NULL) { | |
255 | if (p->data_type != OSSL_PARAM_OCTET_STRING) { | |
784883fc | 256 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); |
a672a02a SL |
257 | return 0; |
258 | } | |
259 | sz = gcm_tls_init(ctx, p->data, p->data_size); | |
260 | if (sz == 0) { | |
784883fc | 261 | ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_AAD); |
a672a02a SL |
262 | return 0; |
263 | } | |
264 | ctx->tls_aad_pad_sz = sz; | |
265 | } | |
266 | ||
267 | p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TLS1_IV_FIXED); | |
268 | if (p != NULL) { | |
269 | if (p->data_type != OSSL_PARAM_OCTET_STRING) { | |
784883fc | 270 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); |
a672a02a SL |
271 | return 0; |
272 | } | |
273 | if (gcm_tls_iv_set_fixed(ctx, p->data, p->data_size) == 0) { | |
784883fc | 274 | ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER); |
a672a02a SL |
275 | return 0; |
276 | } | |
277 | } | |
11b44359 SL |
278 | p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_AEAD_TLS1_SET_IV_INV); |
279 | if (p != NULL) { | |
280 | if (p->data == NULL | |
281 | || p->data_type != OSSL_PARAM_OCTET_STRING | |
282 | || !setivinv(ctx, p->data, p->data_size)) | |
283 | return 0; | |
284 | } | |
285 | ||
a672a02a SL |
286 | |
287 | return 1; | |
288 | } | |
289 | ||
e1178600 SL |
290 | int gcm_stream_update(void *vctx, unsigned char *out, size_t *outl, |
291 | size_t outsize, const unsigned char *in, size_t inl) | |
a672a02a SL |
292 | { |
293 | PROV_GCM_CTX *ctx = (PROV_GCM_CTX *)vctx; | |
294 | ||
4b9c750b MC |
295 | if (inl == 0) { |
296 | *outl = 0; | |
297 | return 1; | |
298 | } | |
299 | ||
a672a02a | 300 | if (outsize < inl) { |
784883fc | 301 | ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL); |
ee0c849e | 302 | return 0; |
a672a02a SL |
303 | } |
304 | ||
305 | if (gcm_cipher_internal(ctx, out, outl, in, inl) <= 0) { | |
784883fc | 306 | ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED); |
ee0c849e | 307 | return 0; |
a672a02a SL |
308 | } |
309 | return 1; | |
310 | } | |
311 | ||
e1178600 SL |
312 | int gcm_stream_final(void *vctx, unsigned char *out, size_t *outl, |
313 | size_t outsize) | |
a672a02a SL |
314 | { |
315 | PROV_GCM_CTX *ctx = (PROV_GCM_CTX *)vctx; | |
316 | int i; | |
317 | ||
f99d3eed P |
318 | if (!ossl_prov_is_running()) |
319 | return 0; | |
320 | ||
a672a02a SL |
321 | i = gcm_cipher_internal(ctx, out, outl, NULL, 0); |
322 | if (i <= 0) | |
323 | return 0; | |
324 | ||
325 | *outl = 0; | |
326 | return 1; | |
327 | } | |
328 | ||
e1178600 SL |
329 | int gcm_cipher(void *vctx, |
330 | unsigned char *out, size_t *outl, size_t outsize, | |
331 | const unsigned char *in, size_t inl) | |
a672a02a SL |
332 | { |
333 | PROV_GCM_CTX *ctx = (PROV_GCM_CTX *)vctx; | |
334 | ||
f99d3eed P |
335 | if (!ossl_prov_is_running()) |
336 | return 0; | |
337 | ||
a672a02a | 338 | if (outsize < inl) { |
784883fc | 339 | ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL); |
ff33581c | 340 | return 0; |
a672a02a SL |
341 | } |
342 | ||
343 | if (gcm_cipher_internal(ctx, out, outl, in, inl) <= 0) | |
ff33581c | 344 | return 0; |
a672a02a SL |
345 | |
346 | *outl = inl; | |
347 | return 1; | |
348 | } | |
349 | ||
350 | /* | |
351 | * See SP800-38D (GCM) Section 8 "Uniqueness requirement on IVS and keys" | |
352 | * | |
353 | * See also 8.2.2 RBG-based construction. | |
354 | * Random construction consists of a free field (which can be NULL) and a | |
355 | * random field which will use a DRBG that can return at least 96 bits of | |
356 | * entropy strength. (The DRBG must be seeded by the FIPS module). | |
357 | */ | |
358 | static int gcm_iv_generate(PROV_GCM_CTX *ctx, int offset) | |
359 | { | |
360 | int sz = ctx->ivlen - offset; | |
361 | ||
362 | /* Must be at least 96 bits */ | |
363 | if (sz <= 0 || ctx->ivlen < GCM_IV_DEFAULT_SIZE) | |
364 | return 0; | |
365 | ||
366 | /* Use DRBG to generate random iv */ | |
993ebac9 | 367 | if (RAND_bytes_ex(ctx->libctx, ctx->iv + offset, sz) <= 0) |
a672a02a SL |
368 | return 0; |
369 | ctx->iv_state = IV_STATE_BUFFERED; | |
370 | ctx->iv_gen_rand = 1; | |
371 | return 1; | |
372 | } | |
373 | ||
374 | static int gcm_cipher_internal(PROV_GCM_CTX *ctx, unsigned char *out, | |
375 | size_t *padlen, const unsigned char *in, | |
376 | size_t len) | |
377 | { | |
378 | size_t olen = 0; | |
379 | int rv = 0; | |
380 | const PROV_GCM_HW *hw = ctx->hw; | |
381 | ||
1c3ace68 | 382 | if (ctx->tls_aad_len != UNINITIALISED_SIZET) |
a672a02a SL |
383 | return gcm_tls_cipher(ctx, out, padlen, in, len); |
384 | ||
385 | if (!ctx->key_set || ctx->iv_state == IV_STATE_FINISHED) | |
386 | goto err; | |
387 | ||
388 | /* | |
389 | * FIPS requires generation of AES-GCM IV's inside the FIPS module. | |
390 | * The IV can still be set externally (the security policy will state that | |
391 | * this is not FIPS compliant). There are some applications | |
392 | * where setting the IV externally is the only option available. | |
393 | */ | |
394 | if (ctx->iv_state == IV_STATE_UNINITIALISED) { | |
395 | if (!ctx->enc || !gcm_iv_generate(ctx, 0)) | |
396 | goto err; | |
397 | } | |
398 | ||
399 | if (ctx->iv_state == IV_STATE_BUFFERED) { | |
400 | if (!hw->setiv(ctx, ctx->iv, ctx->ivlen)) | |
401 | goto err; | |
402 | ctx->iv_state = IV_STATE_COPIED; | |
403 | } | |
404 | ||
405 | if (in != NULL) { | |
406 | /* The input is AAD if out is NULL */ | |
407 | if (out == NULL) { | |
408 | if (!hw->aadupdate(ctx, in, len)) | |
409 | goto err; | |
410 | } else { | |
411 | /* The input is ciphertext OR plaintext */ | |
412 | if (!hw->cipherupdate(ctx, in, len, out)) | |
413 | goto err; | |
414 | } | |
415 | } else { | |
2e9645c8 SL |
416 | /* The tag must be set before actually decrypting data */ |
417 | if (!ctx->enc && ctx->taglen == UNINITIALISED_SIZET) | |
418 | goto err; | |
a672a02a SL |
419 | if (!hw->cipherfinal(ctx, ctx->buf)) |
420 | goto err; | |
421 | ctx->iv_state = IV_STATE_FINISHED; /* Don't reuse the IV */ | |
422 | goto finish; | |
423 | } | |
424 | olen = len; | |
425 | finish: | |
426 | rv = 1; | |
427 | err: | |
428 | *padlen = olen; | |
429 | return rv; | |
430 | } | |
431 | ||
432 | static int gcm_tls_init(PROV_GCM_CTX *dat, unsigned char *aad, size_t aad_len) | |
433 | { | |
434 | unsigned char *buf; | |
435 | size_t len; | |
436 | ||
f99d3eed | 437 | if (!ossl_prov_is_running() || aad_len != EVP_AEAD_TLS1_AAD_LEN) |
a672a02a SL |
438 | return 0; |
439 | ||
440 | /* Save the aad for later use. */ | |
441 | buf = dat->buf; | |
442 | memcpy(buf, aad, aad_len); | |
443 | dat->tls_aad_len = aad_len; | |
444 | dat->tls_enc_records = 0; | |
445 | ||
446 | len = buf[aad_len - 2] << 8 | buf[aad_len - 1]; | |
447 | /* Correct length for explicit iv. */ | |
448 | if (len < EVP_GCM_TLS_EXPLICIT_IV_LEN) | |
449 | return 0; | |
450 | len -= EVP_GCM_TLS_EXPLICIT_IV_LEN; | |
451 | ||
452 | /* If decrypting correct for tag too. */ | |
453 | if (!dat->enc) { | |
454 | if (len < EVP_GCM_TLS_TAG_LEN) | |
455 | return 0; | |
456 | len -= EVP_GCM_TLS_TAG_LEN; | |
457 | } | |
458 | buf[aad_len - 2] = (unsigned char)(len >> 8); | |
459 | buf[aad_len - 1] = (unsigned char)(len & 0xff); | |
460 | /* Extra padding: tag appended to record. */ | |
461 | return EVP_GCM_TLS_TAG_LEN; | |
462 | } | |
463 | ||
464 | static int gcm_tls_iv_set_fixed(PROV_GCM_CTX *ctx, unsigned char *iv, | |
465 | size_t len) | |
466 | { | |
467 | /* Special case: -1 length restores whole IV */ | |
468 | if (len == (size_t)-1) { | |
469 | memcpy(ctx->iv, iv, ctx->ivlen); | |
470 | ctx->iv_gen = 1; | |
471 | ctx->iv_state = IV_STATE_BUFFERED; | |
472 | return 1; | |
473 | } | |
474 | /* Fixed field must be at least 4 bytes and invocation field at least 8 */ | |
475 | if ((len < EVP_GCM_TLS_FIXED_IV_LEN) | |
476 | || (ctx->ivlen - (int)len) < EVP_GCM_TLS_EXPLICIT_IV_LEN) | |
477 | return 0; | |
478 | if (len > 0) | |
479 | memcpy(ctx->iv, iv, len); | |
480 | if (ctx->enc | |
993ebac9 | 481 | && RAND_bytes_ex(ctx->libctx, ctx->iv + len, ctx->ivlen - len) <= 0) |
a672a02a SL |
482 | return 0; |
483 | ctx->iv_gen = 1; | |
484 | ctx->iv_state = IV_STATE_BUFFERED; | |
485 | return 1; | |
486 | } | |
487 | ||
a672a02a SL |
488 | /* |
489 | * Handle TLS GCM packet format. This consists of the last portion of the IV | |
490 | * followed by the payload and finally the tag. On encrypt generate IV, | |
491 | * encrypt payload and write the tag. On verify retrieve IV, decrypt payload | |
492 | * and verify tag. | |
493 | */ | |
494 | static int gcm_tls_cipher(PROV_GCM_CTX *ctx, unsigned char *out, size_t *padlen, | |
495 | const unsigned char *in, size_t len) | |
496 | { | |
1c3ace68 SL |
497 | int rv = 0; |
498 | size_t arg = EVP_GCM_TLS_EXPLICIT_IV_LEN; | |
a672a02a SL |
499 | size_t plen = 0; |
500 | unsigned char *tag = NULL; | |
501 | ||
f99d3eed | 502 | if (!ossl_prov_is_running() || !ctx->key_set) |
a672a02a SL |
503 | goto err; |
504 | ||
505 | /* Encrypt/decrypt must be performed in place */ | |
506 | if (out != in || len < (EVP_GCM_TLS_EXPLICIT_IV_LEN + EVP_GCM_TLS_TAG_LEN)) | |
507 | goto err; | |
508 | ||
509 | /* | |
510 | * Check for too many keys as per FIPS 140-2 IG A.5 "Key/IV Pair Uniqueness | |
511 | * Requirements from SP 800-38D". The requirements is for one party to the | |
512 | * communication to fail after 2^64 - 1 keys. We do this on the encrypting | |
513 | * side only. | |
514 | */ | |
515 | if (ctx->enc && ++ctx->tls_enc_records == 0) { | |
f5f29796 | 516 | ERR_raise(ERR_LIB_PROV, PROV_R_TOO_MANY_RECORDS); |
a672a02a SL |
517 | goto err; |
518 | } | |
519 | ||
a672a02a SL |
520 | /* |
521 | * Set IV from start of buffer or generate IV and write to start of | |
522 | * buffer. | |
523 | */ | |
524 | if (ctx->enc) { | |
11b44359 | 525 | if (!getivgen(ctx, out, arg)) |
a672a02a | 526 | goto err; |
a672a02a | 527 | } else { |
11b44359 | 528 | if (!setivinv(ctx, out, arg)) |
a672a02a SL |
529 | goto err; |
530 | } | |
a672a02a SL |
531 | |
532 | /* Fix buffer and length to point to payload */ | |
533 | in += EVP_GCM_TLS_EXPLICIT_IV_LEN; | |
534 | out += EVP_GCM_TLS_EXPLICIT_IV_LEN; | |
535 | len -= EVP_GCM_TLS_EXPLICIT_IV_LEN + EVP_GCM_TLS_TAG_LEN; | |
536 | ||
537 | tag = ctx->enc ? out + len : (unsigned char *)in + len; | |
538 | if (!ctx->hw->oneshot(ctx, ctx->buf, ctx->tls_aad_len, in, len, out, tag, | |
539 | EVP_GCM_TLS_TAG_LEN)) { | |
540 | if (!ctx->enc) | |
541 | OPENSSL_cleanse(out, len); | |
542 | goto err; | |
543 | } | |
544 | if (ctx->enc) | |
545 | plen = len + EVP_GCM_TLS_EXPLICIT_IV_LEN + EVP_GCM_TLS_TAG_LEN; | |
546 | else | |
547 | plen = len; | |
548 | ||
549 | rv = 1; | |
550 | err: | |
551 | ctx->iv_state = IV_STATE_FINISHED; | |
1c3ace68 | 552 | ctx->tls_aad_len = UNINITIALISED_SIZET; |
a672a02a SL |
553 | *padlen = plen; |
554 | return rv; | |
555 | } | |
11b44359 | 556 |