2 * Copyright 1995-2016 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 "internal/cryptlib.h"
13 #include <openssl/evp.h>
14 #include <openssl/err.h>
15 #include <openssl/rand.h>
16 #include <openssl/rand_drbg.h>
17 #include <openssl/engine.h>
18 #include "internal/evp_int.h"
21 int EVP_CIPHER_CTX_reset(EVP_CIPHER_CTX
*c
)
25 if (c
->cipher
!= NULL
) {
26 if (c
->cipher
->cleanup
&& !c
->cipher
->cleanup(c
))
28 /* Cleanse cipher context data */
29 if (c
->cipher_data
&& c
->cipher
->ctx_size
)
30 OPENSSL_cleanse(c
->cipher_data
, c
->cipher
->ctx_size
);
32 OPENSSL_free(c
->cipher_data
);
33 #ifndef OPENSSL_NO_ENGINE
34 ENGINE_finish(c
->engine
);
36 memset(c
, 0, sizeof(*c
));
40 EVP_CIPHER_CTX
*EVP_CIPHER_CTX_new(void)
42 return OPENSSL_zalloc(sizeof(EVP_CIPHER_CTX
));
45 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX
*ctx
)
47 EVP_CIPHER_CTX_reset(ctx
);
51 int EVP_CipherInit(EVP_CIPHER_CTX
*ctx
, const EVP_CIPHER
*cipher
,
52 const unsigned char *key
, const unsigned char *iv
, int enc
)
55 EVP_CIPHER_CTX_reset(ctx
);
56 return EVP_CipherInit_ex(ctx
, cipher
, NULL
, key
, iv
, enc
);
59 int EVP_CipherInit_ex(EVP_CIPHER_CTX
*ctx
, const EVP_CIPHER
*cipher
,
60 ENGINE
*impl
, const unsigned char *key
,
61 const unsigned char *iv
, int enc
)
70 #ifndef OPENSSL_NO_ENGINE
72 * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
73 * this context may already have an ENGINE! Try to avoid releasing the
74 * previous handle, re-querying for an ENGINE, and having a
75 * reinitialisation, when it may all be unnecessary.
77 if (ctx
->engine
&& ctx
->cipher
78 && (cipher
== NULL
|| cipher
->nid
== ctx
->cipher
->nid
))
83 * Ensure a context left lying around from last time is cleared (the
84 * previous check attempted to avoid this if the same ENGINE and
85 * EVP_CIPHER could be used).
88 unsigned long flags
= ctx
->flags
;
89 EVP_CIPHER_CTX_reset(ctx
);
90 /* Restore encrypt and flags */
94 #ifndef OPENSSL_NO_ENGINE
96 if (!ENGINE_init(impl
)) {
97 EVPerr(EVP_F_EVP_CIPHERINIT_EX
, EVP_R_INITIALIZATION_ERROR
);
101 /* Ask if an ENGINE is reserved for this job */
102 impl
= ENGINE_get_cipher_engine(cipher
->nid
);
104 /* There's an ENGINE for this job ... (apparently) */
105 const EVP_CIPHER
*c
= ENGINE_get_cipher(impl
, cipher
->nid
);
108 * One positive side-effect of US's export control history,
109 * is that we should at least be able to avoid using US
110 * misspellings of "initialisation"?
112 EVPerr(EVP_F_EVP_CIPHERINIT_EX
, EVP_R_INITIALIZATION_ERROR
);
115 /* We'll use the ENGINE's private cipher definition */
118 * Store the ENGINE functional reference so we know 'cipher' came
119 * from an ENGINE and we need to release it when done.
126 ctx
->cipher
= cipher
;
127 if (ctx
->cipher
->ctx_size
) {
128 ctx
->cipher_data
= OPENSSL_zalloc(ctx
->cipher
->ctx_size
);
129 if (ctx
->cipher_data
== NULL
) {
131 EVPerr(EVP_F_EVP_CIPHERINIT_EX
, ERR_R_MALLOC_FAILURE
);
135 ctx
->cipher_data
= NULL
;
137 ctx
->key_len
= cipher
->key_len
;
138 /* Preserve wrap enable flag, zero everything else */
139 ctx
->flags
&= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW
;
140 if (ctx
->cipher
->flags
& EVP_CIPH_CTRL_INIT
) {
141 if (!EVP_CIPHER_CTX_ctrl(ctx
, EVP_CTRL_INIT
, 0, NULL
)) {
143 EVPerr(EVP_F_EVP_CIPHERINIT_EX
, EVP_R_INITIALIZATION_ERROR
);
147 } else if (!ctx
->cipher
) {
148 EVPerr(EVP_F_EVP_CIPHERINIT_EX
, EVP_R_NO_CIPHER_SET
);
151 #ifndef OPENSSL_NO_ENGINE
154 /* we assume block size is a power of 2 in *cryptUpdate */
155 OPENSSL_assert(ctx
->cipher
->block_size
== 1
156 || ctx
->cipher
->block_size
== 8
157 || ctx
->cipher
->block_size
== 16);
159 if (!(ctx
->flags
& EVP_CIPHER_CTX_FLAG_WRAP_ALLOW
)
160 && EVP_CIPHER_CTX_mode(ctx
) == EVP_CIPH_WRAP_MODE
) {
161 EVPerr(EVP_F_EVP_CIPHERINIT_EX
, EVP_R_WRAP_MODE_NOT_ALLOWED
);
165 if (!(EVP_CIPHER_flags(EVP_CIPHER_CTX_cipher(ctx
)) & EVP_CIPH_CUSTOM_IV
)) {
166 switch (EVP_CIPHER_CTX_mode(ctx
)) {
168 case EVP_CIPH_STREAM_CIPHER
:
169 case EVP_CIPH_ECB_MODE
:
172 case EVP_CIPH_CFB_MODE
:
173 case EVP_CIPH_OFB_MODE
:
178 case EVP_CIPH_CBC_MODE
:
180 OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx
) <=
181 (int)sizeof(ctx
->iv
));
183 memcpy(ctx
->oiv
, iv
, EVP_CIPHER_CTX_iv_length(ctx
));
184 memcpy(ctx
->iv
, ctx
->oiv
, EVP_CIPHER_CTX_iv_length(ctx
));
187 case EVP_CIPH_CTR_MODE
:
189 /* Don't reuse IV for CTR mode */
191 memcpy(ctx
->iv
, iv
, EVP_CIPHER_CTX_iv_length(ctx
));
199 if (key
|| (ctx
->cipher
->flags
& EVP_CIPH_ALWAYS_CALL_INIT
)) {
200 if (!ctx
->cipher
->init(ctx
, key
, iv
, enc
))
205 ctx
->block_mask
= ctx
->cipher
->block_size
- 1;
209 int EVP_CipherUpdate(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
,
210 const unsigned char *in
, int inl
)
213 return EVP_EncryptUpdate(ctx
, out
, outl
, in
, inl
);
215 return EVP_DecryptUpdate(ctx
, out
, outl
, in
, inl
);
218 int EVP_CipherFinal_ex(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
)
221 return EVP_EncryptFinal_ex(ctx
, out
, outl
);
223 return EVP_DecryptFinal_ex(ctx
, out
, outl
);
226 int EVP_CipherFinal(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
)
229 return EVP_EncryptFinal(ctx
, out
, outl
);
231 return EVP_DecryptFinal(ctx
, out
, outl
);
234 int EVP_EncryptInit(EVP_CIPHER_CTX
*ctx
, const EVP_CIPHER
*cipher
,
235 const unsigned char *key
, const unsigned char *iv
)
237 return EVP_CipherInit(ctx
, cipher
, key
, iv
, 1);
240 int EVP_EncryptInit_ex(EVP_CIPHER_CTX
*ctx
, const EVP_CIPHER
*cipher
,
241 ENGINE
*impl
, const unsigned char *key
,
242 const unsigned char *iv
)
244 return EVP_CipherInit_ex(ctx
, cipher
, impl
, key
, iv
, 1);
247 int EVP_DecryptInit(EVP_CIPHER_CTX
*ctx
, const EVP_CIPHER
*cipher
,
248 const unsigned char *key
, const unsigned char *iv
)
250 return EVP_CipherInit(ctx
, cipher
, key
, iv
, 0);
253 int EVP_DecryptInit_ex(EVP_CIPHER_CTX
*ctx
, const EVP_CIPHER
*cipher
,
254 ENGINE
*impl
, const unsigned char *key
,
255 const unsigned char *iv
)
257 return EVP_CipherInit_ex(ctx
, cipher
, impl
, key
, iv
, 0);
261 * According to the letter of standard difference between pointers
262 * is specified to be valid only within same object. This makes
263 * it formally challenging to determine if input and output buffers
264 * are not partially overlapping with standard pointer arithmetic.
269 #if defined(OPENSSL_SYS_VMS) && __INITIAL_POINTER_SIZE==64
271 * Then we have VMS that distinguishes itself by adhering to
272 * sizeof(size_t)==4 even in 64-bit builds, which means that
273 * difference between two pointers might be truncated to 32 bits.
274 * In the context one can even wonder how comparison for
275 * equality is implemented. To be on the safe side we adhere to
276 * PTRDIFF_T even for comparison for equality.
278 # define PTRDIFF_T uint64_t
280 # define PTRDIFF_T size_t
283 int is_partially_overlapping(const void *ptr1
, const void *ptr2
, int len
)
285 PTRDIFF_T diff
= (PTRDIFF_T
)ptr1
-(PTRDIFF_T
)ptr2
;
287 * Check for partially overlapping buffers. [Binary logical
288 * operations are used instead of boolean to minimize number
289 * of conditional branches.]
291 int overlapped
= (len
> 0) & (diff
!= 0) & ((diff
< (PTRDIFF_T
)len
) |
292 (diff
> (0 - (PTRDIFF_T
)len
)));
297 int EVP_EncryptUpdate(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
,
298 const unsigned char *in
, int inl
)
300 int i
, j
, bl
, cmpl
= inl
;
302 if (EVP_CIPHER_CTX_test_flags(ctx
, EVP_CIPH_FLAG_LENGTH_BITS
))
303 cmpl
= (cmpl
+ 7) / 8;
305 bl
= ctx
->cipher
->block_size
;
307 if (ctx
->cipher
->flags
& EVP_CIPH_FLAG_CUSTOM_CIPHER
) {
308 /* If block size > 1 then the cipher will have to do this check */
309 if (bl
== 1 && is_partially_overlapping(out
, in
, cmpl
)) {
310 EVPerr(EVP_F_EVP_ENCRYPTUPDATE
, EVP_R_PARTIALLY_OVERLAPPING
);
314 i
= ctx
->cipher
->do_cipher(ctx
, out
, in
, inl
);
326 if (is_partially_overlapping(out
+ ctx
->buf_len
, in
, cmpl
)) {
327 EVPerr(EVP_F_EVP_ENCRYPTUPDATE
, EVP_R_PARTIALLY_OVERLAPPING
);
331 if (ctx
->buf_len
== 0 && (inl
& (ctx
->block_mask
)) == 0) {
332 if (ctx
->cipher
->do_cipher(ctx
, out
, in
, inl
)) {
341 OPENSSL_assert(bl
<= (int)sizeof(ctx
->buf
));
344 memcpy(&(ctx
->buf
[i
]), in
, inl
);
350 memcpy(&(ctx
->buf
[i
]), in
, j
);
353 if (!ctx
->cipher
->do_cipher(ctx
, out
, ctx
->buf
, bl
))
363 if (!ctx
->cipher
->do_cipher(ctx
, out
, in
, inl
))
369 memcpy(ctx
->buf
, &(in
[inl
]), i
);
374 int EVP_EncryptFinal(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
)
377 ret
= EVP_EncryptFinal_ex(ctx
, out
, outl
);
381 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
)
384 unsigned int i
, b
, bl
;
386 if (ctx
->cipher
->flags
& EVP_CIPH_FLAG_CUSTOM_CIPHER
) {
387 ret
= ctx
->cipher
->do_cipher(ctx
, out
, NULL
, 0);
395 b
= ctx
->cipher
->block_size
;
396 OPENSSL_assert(b
<= sizeof(ctx
->buf
));
402 if (ctx
->flags
& EVP_CIPH_NO_PADDING
) {
404 EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX
,
405 EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
);
413 for (i
= bl
; i
< b
; i
++)
415 ret
= ctx
->cipher
->do_cipher(ctx
, out
, ctx
->buf
, b
);
423 int EVP_DecryptUpdate(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
,
424 const unsigned char *in
, int inl
)
426 int fix_len
, cmpl
= inl
;
429 b
= ctx
->cipher
->block_size
;
431 if (EVP_CIPHER_CTX_test_flags(ctx
, EVP_CIPH_FLAG_LENGTH_BITS
))
432 cmpl
= (cmpl
+ 7) / 8;
434 if (ctx
->cipher
->flags
& EVP_CIPH_FLAG_CUSTOM_CIPHER
) {
435 if (b
== 1 && is_partially_overlapping(out
, in
, cmpl
)) {
436 EVPerr(EVP_F_EVP_DECRYPTUPDATE
, EVP_R_PARTIALLY_OVERLAPPING
);
440 fix_len
= ctx
->cipher
->do_cipher(ctx
, out
, in
, inl
);
454 if (ctx
->flags
& EVP_CIPH_NO_PADDING
)
455 return EVP_EncryptUpdate(ctx
, out
, outl
, in
, inl
);
457 OPENSSL_assert(b
<= sizeof(ctx
->final
));
459 if (ctx
->final_used
) {
460 /* see comment about PTRDIFF_T comparison above */
461 if (((PTRDIFF_T
)out
== (PTRDIFF_T
)in
)
462 || is_partially_overlapping(out
, in
, b
)) {
463 EVPerr(EVP_F_EVP_DECRYPTUPDATE
, EVP_R_PARTIALLY_OVERLAPPING
);
466 memcpy(out
, ctx
->final
, b
);
472 if (!EVP_EncryptUpdate(ctx
, out
, outl
, in
, inl
))
476 * if we have 'decrypted' a multiple of block size, make sure we have a
477 * copy of this last block
479 if (b
> 1 && !ctx
->buf_len
) {
482 memcpy(ctx
->final
, &out
[*outl
], b
);
492 int EVP_DecryptFinal(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
)
495 ret
= EVP_DecryptFinal_ex(ctx
, out
, outl
);
499 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX
*ctx
, unsigned char *out
, int *outl
)
505 if (ctx
->cipher
->flags
& EVP_CIPH_FLAG_CUSTOM_CIPHER
) {
506 i
= ctx
->cipher
->do_cipher(ctx
, out
, NULL
, 0);
514 b
= ctx
->cipher
->block_size
;
515 if (ctx
->flags
& EVP_CIPH_NO_PADDING
) {
517 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX
,
518 EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
);
525 if (ctx
->buf_len
|| !ctx
->final_used
) {
526 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX
, EVP_R_WRONG_FINAL_BLOCK_LENGTH
);
529 OPENSSL_assert(b
<= sizeof(ctx
->final
));
532 * The following assumes that the ciphertext has been authenticated.
533 * Otherwise it provides a padding oracle.
535 n
= ctx
->final
[b
- 1];
536 if (n
== 0 || n
> (int)b
) {
537 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX
, EVP_R_BAD_DECRYPT
);
540 for (i
= 0; i
< n
; i
++) {
541 if (ctx
->final
[--b
] != n
) {
542 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX
, EVP_R_BAD_DECRYPT
);
546 n
= ctx
->cipher
->block_size
- n
;
547 for (i
= 0; i
< n
; i
++)
548 out
[i
] = ctx
->final
[i
];
555 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX
*c
, int keylen
)
557 if (c
->cipher
->flags
& EVP_CIPH_CUSTOM_KEY_LENGTH
)
558 return EVP_CIPHER_CTX_ctrl(c
, EVP_CTRL_SET_KEY_LENGTH
, keylen
, NULL
);
559 if (c
->key_len
== keylen
)
561 if ((keylen
> 0) && (c
->cipher
->flags
& EVP_CIPH_VARIABLE_LENGTH
)) {
565 EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH
, EVP_R_INVALID_KEY_LENGTH
);
569 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX
*ctx
, int pad
)
572 ctx
->flags
&= ~EVP_CIPH_NO_PADDING
;
574 ctx
->flags
|= EVP_CIPH_NO_PADDING
;
578 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX
*ctx
, int type
, int arg
, void *ptr
)
583 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL
, EVP_R_NO_CIPHER_SET
);
587 if (!ctx
->cipher
->ctrl
) {
588 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL
, EVP_R_CTRL_NOT_IMPLEMENTED
);
592 ret
= ctx
->cipher
->ctrl(ctx
, type
, arg
, ptr
);
594 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL
,
595 EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED
);
601 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX
*ctx
, unsigned char *key
)
603 if (ctx
->cipher
->flags
& EVP_CIPH_RAND_KEY
)
604 return EVP_CIPHER_CTX_ctrl(ctx
, EVP_CTRL_RAND_KEY
, 0, key
);
605 if (RAND_bytes(key
, ctx
->key_len
) <= 0)
610 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX
*out
, const EVP_CIPHER_CTX
*in
)
612 if ((in
== NULL
) || (in
->cipher
== NULL
)) {
613 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY
, EVP_R_INPUT_NOT_INITIALIZED
);
616 #ifndef OPENSSL_NO_ENGINE
617 /* Make sure it's safe to copy a cipher context using an ENGINE */
618 if (in
->engine
&& !ENGINE_init(in
->engine
)) {
619 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY
, ERR_R_ENGINE_LIB
);
624 EVP_CIPHER_CTX_reset(out
);
625 memcpy(out
, in
, sizeof(*out
));
627 if (in
->cipher_data
&& in
->cipher
->ctx_size
) {
628 out
->cipher_data
= OPENSSL_malloc(in
->cipher
->ctx_size
);
629 if (out
->cipher_data
== NULL
) {
631 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY
, ERR_R_MALLOC_FAILURE
);
634 memcpy(out
->cipher_data
, in
->cipher_data
, in
->cipher
->ctx_size
);
637 if (in
->cipher
->flags
& EVP_CIPH_CUSTOM_COPY
)
638 if (!in
->cipher
->ctrl((EVP_CIPHER_CTX
*)in
, EVP_CTRL_COPY
, 0, out
)) {
640 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY
, EVP_R_INITIALIZATION_ERROR
);