2 * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
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
10 /* Dispatch functions for gcm mode */
12 #include "cipher_locl.h"
13 #include "internal/ciphers/cipher_gcm.h"
14 #include "internal/providercommonerr.h"
15 #include "crypto/rand.h"
16 #include "internal/provider_ctx.h"
18 static int gcm_tls_init(PROV_GCM_CTX
*dat
, unsigned char *aad
, size_t aad_len
);
19 static int gcm_tls_iv_set_fixed(PROV_GCM_CTX
*ctx
, unsigned char *iv
,
21 static int gcm_tls_cipher(PROV_GCM_CTX
*ctx
, unsigned char *out
, size_t *padlen
,
22 const unsigned char *in
, size_t len
);
23 static int gcm_cipher_internal(PROV_GCM_CTX
*ctx
, unsigned char *out
,
24 size_t *padlen
, const unsigned char *in
,
27 void gcm_initctx(void *provctx
, PROV_GCM_CTX
*ctx
, size_t keybits
,
28 const PROV_GCM_HW
*hw
, size_t ivlen_min
)
31 ctx
->mode
= EVP_CIPH_GCM_MODE
;
32 ctx
->taglen
= UNINITIALISED_SIZET
;
33 ctx
->tls_aad_len
= UNINITIALISED_SIZET
;
34 ctx
->ivlen_min
= ivlen_min
;
35 ctx
->ivlen
= (EVP_GCM_TLS_FIXED_IV_LEN
+ EVP_GCM_TLS_EXPLICIT_IV_LEN
);
36 ctx
->keylen
= keybits
/ 8;
38 ctx
->libctx
= PROV_LIBRARY_CONTEXT_OF(provctx
);
41 void gcm_deinitctx(PROV_GCM_CTX
*ctx
)
43 OPENSSL_cleanse(ctx
->iv
, sizeof(ctx
->iv
));
46 static int gcm_init(void *vctx
, const unsigned char *key
, size_t keylen
,
47 const unsigned char *iv
, size_t ivlen
, int enc
)
49 PROV_GCM_CTX
*ctx
= (PROV_GCM_CTX
*)vctx
;
54 if (ivlen
< ctx
->ivlen_min
|| ivlen
> sizeof(ctx
->iv
)) {
55 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_IV_LENGTH
);
59 memcpy(ctx
->iv
, iv
, ctx
->ivlen
);
60 ctx
->iv_state
= IV_STATE_BUFFERED
;
64 if (keylen
!= ctx
->keylen
) {
65 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_KEY_LENGTH
);
68 return ctx
->hw
->setkey(ctx
, key
, ctx
->keylen
);
73 int gcm_einit(void *vctx
, const unsigned char *key
, size_t keylen
,
74 const unsigned char *iv
, size_t ivlen
)
76 return gcm_init(vctx
, key
, keylen
, iv
, ivlen
, 1);
79 int gcm_dinit(void *vctx
, const unsigned char *key
, size_t keylen
,
80 const unsigned char *iv
, size_t ivlen
)
82 return gcm_init(vctx
, key
, keylen
, iv
, ivlen
, 0);
85 int gcm_get_ctx_params(void *vctx
, OSSL_PARAM params
[])
87 PROV_GCM_CTX
*ctx
= (PROV_GCM_CTX
*)vctx
;
91 p
= OSSL_PARAM_locate(params
, OSSL_CIPHER_PARAM_IVLEN
);
92 if (p
!= NULL
&& !OSSL_PARAM_set_size_t(p
, ctx
->ivlen
)) {
93 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_SET_PARAMETER
);
96 p
= OSSL_PARAM_locate(params
, OSSL_CIPHER_PARAM_KEYLEN
);
97 if (p
!= NULL
&& !OSSL_PARAM_set_size_t(p
, ctx
->keylen
)) {
98 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_SET_PARAMETER
);
101 p
= OSSL_PARAM_locate(params
, OSSL_CIPHER_PARAM_AEAD_TAGLEN
);
103 size_t taglen
= (ctx
->taglen
!= UNINITIALISED_SIZET
) ? ctx
->taglen
:
106 if (!OSSL_PARAM_set_size_t(p
, taglen
)) {
107 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_SET_PARAMETER
);
112 p
= OSSL_PARAM_locate(params
, OSSL_CIPHER_PARAM_IV
);
114 if (ctx
->iv_gen
!= 1 && ctx
->iv_gen_rand
!= 1)
116 if (ctx
->ivlen
!= p
->data_size
) {
117 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_IV_LENGTH
);
120 if (!OSSL_PARAM_set_octet_string(p
, ctx
->iv
, ctx
->ivlen
)) {
121 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_SET_PARAMETER
);
126 p
= OSSL_PARAM_locate(params
, OSSL_CIPHER_PARAM_AEAD_TLS1_AAD_PAD
);
127 if (p
!= NULL
&& !OSSL_PARAM_set_size_t(p
, ctx
->tls_aad_pad_sz
)) {
128 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_SET_PARAMETER
);
131 p
= OSSL_PARAM_locate(params
, OSSL_CIPHER_PARAM_AEAD_TAG
);
135 || sz
> EVP_GCM_TLS_TAG_LEN
137 || ctx
->taglen
== UNINITIALISED_SIZET
) {
138 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_TAG
);
141 if (!OSSL_PARAM_set_octet_string(p
, ctx
->buf
, sz
)) {
142 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_SET_PARAMETER
);
150 int gcm_set_ctx_params(void *vctx
, const OSSL_PARAM params
[])
152 PROV_GCM_CTX
*ctx
= (PROV_GCM_CTX
*)vctx
;
157 p
= OSSL_PARAM_locate_const(params
, OSSL_CIPHER_PARAM_AEAD_TAG
);
160 if (!OSSL_PARAM_get_octet_string(p
, &vp
, EVP_GCM_TLS_TAG_LEN
, &sz
)) {
161 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_GET_PARAMETER
);
164 if (sz
== 0 || ctx
->enc
) {
165 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_TAG
);
171 p
= OSSL_PARAM_locate_const(params
, OSSL_CIPHER_PARAM_AEAD_IVLEN
);
173 if (!OSSL_PARAM_get_size_t(p
, &sz
)) {
174 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_GET_PARAMETER
);
177 if (sz
== 0 || sz
> sizeof(ctx
->iv
)) {
178 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_IV_LENGTH
);
184 p
= OSSL_PARAM_locate_const(params
, OSSL_CIPHER_PARAM_AEAD_TLS1_AAD
);
186 if (p
->data_type
!= OSSL_PARAM_OCTET_STRING
) {
187 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_GET_PARAMETER
);
190 sz
= gcm_tls_init(ctx
, p
->data
, p
->data_size
);
192 ERR_raise(ERR_LIB_PROV
, PROV_R_INVALID_AAD
);
195 ctx
->tls_aad_pad_sz
= sz
;
198 p
= OSSL_PARAM_locate_const(params
, OSSL_CIPHER_PARAM_AEAD_TLS1_IV_FIXED
);
200 if (p
->data_type
!= OSSL_PARAM_OCTET_STRING
) {
201 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_GET_PARAMETER
);
204 if (gcm_tls_iv_set_fixed(ctx
, p
->data
, p
->data_size
) == 0) {
205 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_GET_PARAMETER
);
211 * TODO(3.0) Temporary solution to address fuzz test crash, which will be
212 * reworked once the discussion in PR #9510 is resolved. i.e- We need a
213 * general solution for handling missing parameters inside set_params and
214 * get_params methods.
216 p
= OSSL_PARAM_locate_const(params
, OSSL_CIPHER_PARAM_KEYLEN
);
220 if (!OSSL_PARAM_get_size_t(p
, &keylen
)) {
221 ERR_raise(ERR_LIB_PROV
, PROV_R_FAILED_TO_GET_PARAMETER
);
224 /* The key length can not be modified for gcm mode */
225 if (keylen
!= ctx
->keylen
)
232 int gcm_stream_update(void *vctx
, unsigned char *out
, size_t *outl
,
233 size_t outsize
, const unsigned char *in
, size_t inl
)
235 PROV_GCM_CTX
*ctx
= (PROV_GCM_CTX
*)vctx
;
238 ERR_raise(ERR_LIB_PROV
, PROV_R_OUTPUT_BUFFER_TOO_SMALL
);
242 if (gcm_cipher_internal(ctx
, out
, outl
, in
, inl
) <= 0) {
243 ERR_raise(ERR_LIB_PROV
, PROV_R_CIPHER_OPERATION_FAILED
);
249 int gcm_stream_final(void *vctx
, unsigned char *out
, size_t *outl
,
252 PROV_GCM_CTX
*ctx
= (PROV_GCM_CTX
*)vctx
;
255 i
= gcm_cipher_internal(ctx
, out
, outl
, NULL
, 0);
263 int gcm_cipher(void *vctx
,
264 unsigned char *out
, size_t *outl
, size_t outsize
,
265 const unsigned char *in
, size_t inl
)
267 PROV_GCM_CTX
*ctx
= (PROV_GCM_CTX
*)vctx
;
270 ERR_raise(ERR_LIB_PROV
, PROV_R_OUTPUT_BUFFER_TOO_SMALL
);
274 if (gcm_cipher_internal(ctx
, out
, outl
, in
, inl
) <= 0)
282 * See SP800-38D (GCM) Section 8 "Uniqueness requirement on IVS and keys"
284 * See also 8.2.2 RBG-based construction.
285 * Random construction consists of a free field (which can be NULL) and a
286 * random field which will use a DRBG that can return at least 96 bits of
287 * entropy strength. (The DRBG must be seeded by the FIPS module).
289 static int gcm_iv_generate(PROV_GCM_CTX
*ctx
, int offset
)
291 int sz
= ctx
->ivlen
- offset
;
293 /* Must be at least 96 bits */
294 if (sz
<= 0 || ctx
->ivlen
< GCM_IV_DEFAULT_SIZE
)
297 /* Use DRBG to generate random iv */
298 if (rand_bytes_ex(ctx
->libctx
, ctx
->iv
+ offset
, sz
) <= 0)
300 ctx
->iv_state
= IV_STATE_BUFFERED
;
301 ctx
->iv_gen_rand
= 1;
305 static int gcm_cipher_internal(PROV_GCM_CTX
*ctx
, unsigned char *out
,
306 size_t *padlen
, const unsigned char *in
,
311 const PROV_GCM_HW
*hw
= ctx
->hw
;
313 if (ctx
->tls_aad_len
!= UNINITIALISED_SIZET
)
314 return gcm_tls_cipher(ctx
, out
, padlen
, in
, len
);
316 if (!ctx
->key_set
|| ctx
->iv_state
== IV_STATE_FINISHED
)
320 * FIPS requires generation of AES-GCM IV's inside the FIPS module.
321 * The IV can still be set externally (the security policy will state that
322 * this is not FIPS compliant). There are some applications
323 * where setting the IV externally is the only option available.
325 if (ctx
->iv_state
== IV_STATE_UNINITIALISED
) {
326 if (!ctx
->enc
|| !gcm_iv_generate(ctx
, 0))
330 if (ctx
->iv_state
== IV_STATE_BUFFERED
) {
331 if (!hw
->setiv(ctx
, ctx
->iv
, ctx
->ivlen
))
333 ctx
->iv_state
= IV_STATE_COPIED
;
337 /* The input is AAD if out is NULL */
339 if (!hw
->aadupdate(ctx
, in
, len
))
342 /* The input is ciphertext OR plaintext */
343 if (!hw
->cipherupdate(ctx
, in
, len
, out
))
347 /* The tag must be set before actually decrypting data */
348 if (!ctx
->enc
&& ctx
->taglen
== UNINITIALISED_SIZET
)
350 if (!hw
->cipherfinal(ctx
, ctx
->buf
))
352 ctx
->iv_state
= IV_STATE_FINISHED
; /* Don't reuse the IV */
363 static int gcm_tls_init(PROV_GCM_CTX
*dat
, unsigned char *aad
, size_t aad_len
)
368 if (aad_len
!= EVP_AEAD_TLS1_AAD_LEN
)
371 /* Save the aad for later use. */
373 memcpy(buf
, aad
, aad_len
);
374 dat
->tls_aad_len
= aad_len
;
375 dat
->tls_enc_records
= 0;
377 len
= buf
[aad_len
- 2] << 8 | buf
[aad_len
- 1];
378 /* Correct length for explicit iv. */
379 if (len
< EVP_GCM_TLS_EXPLICIT_IV_LEN
)
381 len
-= EVP_GCM_TLS_EXPLICIT_IV_LEN
;
383 /* If decrypting correct for tag too. */
385 if (len
< EVP_GCM_TLS_TAG_LEN
)
387 len
-= EVP_GCM_TLS_TAG_LEN
;
389 buf
[aad_len
- 2] = (unsigned char)(len
>> 8);
390 buf
[aad_len
- 1] = (unsigned char)(len
& 0xff);
391 /* Extra padding: tag appended to record. */
392 return EVP_GCM_TLS_TAG_LEN
;
395 static int gcm_tls_iv_set_fixed(PROV_GCM_CTX
*ctx
, unsigned char *iv
,
398 /* Special case: -1 length restores whole IV */
399 if (len
== (size_t)-1) {
400 memcpy(ctx
->iv
, iv
, ctx
->ivlen
);
402 ctx
->iv_state
= IV_STATE_BUFFERED
;
405 /* Fixed field must be at least 4 bytes and invocation field at least 8 */
406 if ((len
< EVP_GCM_TLS_FIXED_IV_LEN
)
407 || (ctx
->ivlen
- (int)len
) < EVP_GCM_TLS_EXPLICIT_IV_LEN
)
410 memcpy(ctx
->iv
, iv
, len
);
412 && rand_bytes_ex(ctx
->libctx
, ctx
->iv
+ len
, ctx
->ivlen
- len
) <= 0)
415 ctx
->iv_state
= IV_STATE_BUFFERED
;
419 /* increment counter (64-bit int) by 1 */
420 static void ctr64_inc(unsigned char *counter
)
436 * Handle TLS GCM packet format. This consists of the last portion of the IV
437 * followed by the payload and finally the tag. On encrypt generate IV,
438 * encrypt payload and write the tag. On verify retrieve IV, decrypt payload
441 static int gcm_tls_cipher(PROV_GCM_CTX
*ctx
, unsigned char *out
, size_t *padlen
,
442 const unsigned char *in
, size_t len
)
445 size_t arg
= EVP_GCM_TLS_EXPLICIT_IV_LEN
;
447 unsigned char *tag
= NULL
;
452 /* Encrypt/decrypt must be performed in place */
453 if (out
!= in
|| len
< (EVP_GCM_TLS_EXPLICIT_IV_LEN
+ EVP_GCM_TLS_TAG_LEN
))
457 * Check for too many keys as per FIPS 140-2 IG A.5 "Key/IV Pair Uniqueness
458 * Requirements from SP 800-38D". The requirements is for one party to the
459 * communication to fail after 2^64 - 1 keys. We do this on the encrypting
462 if (ctx
->enc
&& ++ctx
->tls_enc_records
== 0) {
463 ERR_raise(ERR_LIB_PROV
, EVP_R_TOO_MANY_RECORDS
);
467 if (ctx
->iv_gen
== 0)
470 * Set IV from start of buffer or generate IV and write to start of
474 if (!ctx
->hw
->setiv(ctx
, ctx
->iv
, ctx
->ivlen
))
476 if (arg
> ctx
->ivlen
)
478 memcpy(out
, ctx
->iv
+ ctx
->ivlen
- arg
, arg
);
480 * Invocation field will be at least 8 bytes in size and so no need
481 * to check wrap around or increment more than last 8 bytes.
483 ctr64_inc(ctx
->iv
+ ctx
->ivlen
- 8);
485 memcpy(ctx
->iv
+ ctx
->ivlen
- arg
, out
, arg
);
486 if (!ctx
->hw
->setiv(ctx
, ctx
->iv
, ctx
->ivlen
))
489 ctx
->iv_state
= IV_STATE_COPIED
;
491 /* Fix buffer and length to point to payload */
492 in
+= EVP_GCM_TLS_EXPLICIT_IV_LEN
;
493 out
+= EVP_GCM_TLS_EXPLICIT_IV_LEN
;
494 len
-= EVP_GCM_TLS_EXPLICIT_IV_LEN
+ EVP_GCM_TLS_TAG_LEN
;
496 tag
= ctx
->enc
? out
+ len
: (unsigned char *)in
+ len
;
497 if (!ctx
->hw
->oneshot(ctx
, ctx
->buf
, ctx
->tls_aad_len
, in
, len
, out
, tag
,
498 EVP_GCM_TLS_TAG_LEN
)) {
500 OPENSSL_cleanse(out
, len
);
504 plen
= len
+ EVP_GCM_TLS_EXPLICIT_IV_LEN
+ EVP_GCM_TLS_TAG_LEN
;
510 ctx
->iv_state
= IV_STATE_FINISHED
;
511 ctx
->tls_aad_len
= UNINITIALISED_SIZET
;