1 /* crypto/evp/evp_enc.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
61 #include <openssl/evp.h>
62 #include <openssl/err.h>
63 #include <openssl/rand.h>
64 #ifndef OPENSSL_NO_ENGINE
65 #include <openssl/engine.h>
67 #include "../constant_time_locl.h"
70 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;
72 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
74 memset(ctx,0,sizeof(EVP_CIPHER_CTX));
75 /* ctx->cipher=NULL; */
78 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
80 EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);
82 EVP_CIPHER_CTX_init(ctx);
86 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
87 const unsigned char *key, const unsigned char *iv, int enc)
90 EVP_CIPHER_CTX_init(ctx);
91 return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc);
94 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
95 const unsigned char *key, const unsigned char *iv, int enc)
105 #ifndef OPENSSL_NO_ENGINE
106 /* Whether it's nice or not, "Inits" can be used on "Final"'d contexts
107 * so this context may already have an ENGINE! Try to avoid releasing
108 * the previous handle, re-querying for an ENGINE, and having a
109 * reinitialisation, when it may all be unecessary. */
110 if (ctx->engine && ctx->cipher && (!cipher ||
111 (cipher && (cipher->nid == ctx->cipher->nid))))
116 /* Ensure a context left lying around from last time is cleared
117 * (the previous check attempted to avoid this if the same
118 * ENGINE and EVP_CIPHER could be used). */
121 unsigned long flags = ctx->flags;
122 EVP_CIPHER_CTX_cleanup(ctx);
123 /* Restore encrypt and flags */
127 #ifndef OPENSSL_NO_ENGINE
130 if (!ENGINE_init(impl))
132 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
137 /* Ask if an ENGINE is reserved for this job */
138 impl = ENGINE_get_cipher_engine(cipher->nid);
141 /* There's an ENGINE for this job ... (apparently) */
142 const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
145 /* One positive side-effect of US's export
146 * control history, is that we should at least
147 * be able to avoid using US mispellings of
148 * "initialisation"? */
149 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
152 /* We'll use the ENGINE's private cipher definition */
154 /* Store the ENGINE functional reference so we know
155 * 'cipher' came from an ENGINE and we need to release
164 if (ctx->cipher->ctx_size)
166 ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
167 if (!ctx->cipher_data)
169 EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
175 ctx->cipher_data = NULL;
177 ctx->key_len = cipher->key_len;
178 /* Preserve wrap enable flag, zero everything else */
179 ctx->flags &= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW;
180 if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)
182 if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))
184 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
189 else if(!ctx->cipher)
191 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
194 #ifndef OPENSSL_NO_ENGINE
197 /* we assume block size is a power of 2 in *cryptUpdate */
198 OPENSSL_assert(ctx->cipher->block_size == 1
199 || ctx->cipher->block_size == 8
200 || ctx->cipher->block_size == 16);
202 if(!(ctx->flags & EVP_CIPHER_CTX_FLAG_WRAP_ALLOW)
203 && EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_WRAP_MODE)
205 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_WRAP_MODE_NOT_ALLOWED);
209 if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
210 switch(EVP_CIPHER_CTX_mode(ctx)) {
212 case EVP_CIPH_STREAM_CIPHER:
213 case EVP_CIPH_ECB_MODE:
216 case EVP_CIPH_CFB_MODE:
217 case EVP_CIPH_OFB_MODE:
222 case EVP_CIPH_CBC_MODE:
224 OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
225 (int)sizeof(ctx->iv));
226 if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
227 memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
230 case EVP_CIPH_CTR_MODE:
232 /* Don't reuse IV for CTR mode */
234 memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
244 if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
245 if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;
249 ctx->block_mask=ctx->cipher->block_size-1;
253 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
254 const unsigned char *in, int inl)
257 return EVP_EncryptUpdate(ctx,out,outl,in,inl);
258 else return EVP_DecryptUpdate(ctx,out,outl,in,inl);
261 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
264 return EVP_EncryptFinal_ex(ctx,out,outl);
265 else return EVP_DecryptFinal_ex(ctx,out,outl);
268 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
271 return EVP_EncryptFinal(ctx,out,outl);
272 else return EVP_DecryptFinal(ctx,out,outl);
275 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
276 const unsigned char *key, const unsigned char *iv)
278 return EVP_CipherInit(ctx, cipher, key, iv, 1);
281 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
282 const unsigned char *key, const unsigned char *iv)
284 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
287 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
288 const unsigned char *key, const unsigned char *iv)
290 return EVP_CipherInit(ctx, cipher, key, iv, 0);
293 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
294 const unsigned char *key, const unsigned char *iv)
296 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
299 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
300 const unsigned char *in, int inl)
304 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
306 i = ctx->cipher->do_cipher(ctx, out, in, inl);
320 if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
322 if(ctx->cipher->do_cipher(ctx,out,in,inl))
334 bl=ctx->cipher->block_size;
335 OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
340 memcpy(&(ctx->buf[i]),in,inl);
348 memcpy(&(ctx->buf[i]),in,j);
349 if(!ctx->cipher->do_cipher(ctx,out,ctx->buf,bl)) return 0;
362 if(!ctx->cipher->do_cipher(ctx,out,in,inl)) return 0;
367 memcpy(ctx->buf,&(in[inl]),i);
372 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
375 ret = EVP_EncryptFinal_ex(ctx, out, outl);
379 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
382 unsigned int i, b, bl;
384 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
386 ret = ctx->cipher->do_cipher(ctx, out, NULL, 0);
394 b=ctx->cipher->block_size;
395 OPENSSL_assert(b <= sizeof ctx->buf);
402 if (ctx->flags & EVP_CIPH_NO_PADDING)
406 EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
416 ret=ctx->cipher->do_cipher(ctx,out,ctx->buf,b);
425 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
426 const unsigned char *in, int inl)
431 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
433 fix_len = ctx->cipher->do_cipher(ctx, out, in, inl);
450 if (ctx->flags & EVP_CIPH_NO_PADDING)
451 return EVP_EncryptUpdate(ctx, out, outl, in, inl);
453 b=ctx->cipher->block_size;
454 OPENSSL_assert(b <= sizeof ctx->final);
458 memcpy(out,ctx->final,b);
466 if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))
469 /* if we have 'decrypted' a multiple of block size, make sure
470 * we have a copy of this last block */
471 if (b > 1 && !ctx->buf_len)
475 memcpy(ctx->final,&out[*outl],b);
486 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
489 ret = EVP_DecryptFinal_ex(ctx, out, outl);
493 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
496 unsigned char pad, padding_good;
499 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
501 int ret = ctx->cipher->do_cipher(ctx, out, NULL, 0);
509 b=(unsigned int)(ctx->cipher->block_size);
510 if (ctx->flags & EVP_CIPH_NO_PADDING)
514 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
522 if (ctx->buf_len || !ctx->final_used)
524 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
527 OPENSSL_assert(b <= sizeof ctx->final);
530 padding_good = (unsigned char)(~constant_time_is_zero_8(pad));
531 padding_good &= constant_time_ge_8(b, pad);
533 for (i = 1; i < b; ++i)
535 unsigned char is_pad_index = constant_time_lt_8(i, pad);
536 unsigned char pad_byte_good = constant_time_eq_8(ctx->final[b-i-1], pad);
537 padding_good &= constant_time_select_8(is_pad_index, pad_byte_good, 0xff);
541 * At least 1 byte is always padding, so we always write b - 1
542 * bytes to avoid a timing leak. The caller is required to have |b|
543 * bytes space in |out| by the API contract.
545 for (i = 0; i < b - 1; ++i)
546 out[i] = ctx->final[i] & padding_good;
547 /* Safe cast: for a good padding, EVP_MAX_IV_LENGTH >= b >= pad */
548 *outl = padding_good & ((unsigned char)(b - pad));
549 return padding_good & 1;
558 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
562 EVP_CIPHER_CTX_cleanup(ctx);
567 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
569 if (c->cipher != NULL)
571 if(c->cipher->cleanup && !c->cipher->cleanup(c))
573 /* Cleanse cipher context data */
575 OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
578 OPENSSL_free(c->cipher_data);
579 #ifndef OPENSSL_NO_ENGINE
581 /* The EVP_CIPHER we used belongs to an ENGINE, release the
582 * functional reference we held for this reason. */
583 ENGINE_finish(c->engine);
585 memset(c,0,sizeof(EVP_CIPHER_CTX));
589 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
591 if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
592 return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
593 if(c->key_len == keylen) return 1;
594 if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))
599 EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);
603 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
605 if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;
606 else ctx->flags |= EVP_CIPH_NO_PADDING;
610 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
614 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
618 if(!ctx->cipher->ctrl) {
619 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
623 ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
625 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
631 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
633 if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
634 return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
635 if (RAND_bytes(key, ctx->key_len) <= 0)
640 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
642 if ((in == NULL) || (in->cipher == NULL))
644 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,EVP_R_INPUT_NOT_INITIALIZED);
647 #ifndef OPENSSL_NO_ENGINE
648 /* Make sure it's safe to copy a cipher context using an ENGINE */
649 if (in->engine && !ENGINE_init(in->engine))
651 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_ENGINE_LIB);
656 EVP_CIPHER_CTX_cleanup(out);
657 memcpy(out,in,sizeof *out);
659 if (in->cipher_data && in->cipher->ctx_size)
661 out->cipher_data=OPENSSL_malloc(in->cipher->ctx_size);
662 if (!out->cipher_data)
664 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_MALLOC_FAILURE);
667 memcpy(out->cipher_data,in->cipher_data,in->cipher->ctx_size);
670 if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
671 return in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out);