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>
68 #include <openssl/fips.h>
70 #include "../constant_time_locl.h"
74 #define M_do_cipher(ctx, out, in, inl) FIPS_cipher(ctx, out, in, inl)
76 #define M_do_cipher(ctx, out, in, inl) ctx->cipher->do_cipher(ctx, out, in, inl)
80 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;
82 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
84 memset(ctx,0,sizeof(EVP_CIPHER_CTX));
85 /* ctx->cipher=NULL; */
88 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
90 EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);
92 EVP_CIPHER_CTX_init(ctx);
96 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
97 const unsigned char *key, const unsigned char *iv, int enc)
100 EVP_CIPHER_CTX_init(ctx);
101 return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc);
104 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
105 const unsigned char *key, const unsigned char *iv, int enc)
115 #ifndef OPENSSL_NO_ENGINE
116 /* Whether it's nice or not, "Inits" can be used on "Final"'d contexts
117 * so this context may already have an ENGINE! Try to avoid releasing
118 * the previous handle, re-querying for an ENGINE, and having a
119 * reinitialisation, when it may all be unecessary. */
120 if (ctx->engine && ctx->cipher && (!cipher ||
121 (cipher && (cipher->nid == ctx->cipher->nid))))
126 /* Ensure a context left lying around from last time is cleared
127 * (the previous check attempted to avoid this if the same
128 * ENGINE and EVP_CIPHER could be used). */
131 unsigned long flags = ctx->flags;
132 EVP_CIPHER_CTX_cleanup(ctx);
133 /* Restore encrypt and flags */
137 #ifndef OPENSSL_NO_ENGINE
140 if (!ENGINE_init(impl))
142 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
147 /* Ask if an ENGINE is reserved for this job */
148 impl = ENGINE_get_cipher_engine(cipher->nid);
151 /* There's an ENGINE for this job ... (apparently) */
152 const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
155 /* One positive side-effect of US's export
156 * control history, is that we should at least
157 * be able to avoid using US mispellings of
158 * "initialisation"? */
159 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
162 /* We'll use the ENGINE's private cipher definition */
164 /* Store the ENGINE functional reference so we know
165 * 'cipher' came from an ENGINE and we need to release
176 const EVP_CIPHER *fcipher;
178 fcipher = evp_get_fips_cipher(cipher);
181 return FIPS_cipherinit(ctx, cipher, key, iv, enc);
185 if (ctx->cipher->ctx_size)
187 ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
188 if (!ctx->cipher_data)
190 EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);
196 ctx->cipher_data = NULL;
198 ctx->key_len = cipher->key_len;
199 /* Preserve wrap enable flag, zero everything else */
200 ctx->flags &= EVP_CIPHER_CTX_FLAG_WRAP_ALLOW;
201 if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)
203 if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))
205 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
210 else if(!ctx->cipher)
212 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
215 #ifndef OPENSSL_NO_ENGINE
220 return FIPS_cipherinit(ctx, cipher, key, iv, enc);
222 /* we assume block size is a power of 2 in *cryptUpdate */
223 OPENSSL_assert(ctx->cipher->block_size == 1
224 || ctx->cipher->block_size == 8
225 || ctx->cipher->block_size == 16);
227 if(!(ctx->flags & EVP_CIPHER_CTX_FLAG_WRAP_ALLOW)
228 && EVP_CIPHER_CTX_mode(ctx) == EVP_CIPH_WRAP_MODE)
230 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_WRAP_MODE_NOT_ALLOWED);
234 if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
235 switch(EVP_CIPHER_CTX_mode(ctx)) {
237 case EVP_CIPH_STREAM_CIPHER:
238 case EVP_CIPH_ECB_MODE:
241 case EVP_CIPH_CFB_MODE:
242 case EVP_CIPH_OFB_MODE:
247 case EVP_CIPH_CBC_MODE:
249 OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=
250 (int)sizeof(ctx->iv));
251 if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));
252 memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));
255 case EVP_CIPH_CTR_MODE:
257 /* Don't reuse IV for CTR mode */
259 memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
269 if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
270 if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;
274 ctx->block_mask=ctx->cipher->block_size-1;
278 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
279 const unsigned char *in, int inl)
282 return EVP_EncryptUpdate(ctx,out,outl,in,inl);
283 else return EVP_DecryptUpdate(ctx,out,outl,in,inl);
286 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
289 return EVP_EncryptFinal_ex(ctx,out,outl);
290 else return EVP_DecryptFinal_ex(ctx,out,outl);
293 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
296 return EVP_EncryptFinal(ctx,out,outl);
297 else return EVP_DecryptFinal(ctx,out,outl);
300 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
301 const unsigned char *key, const unsigned char *iv)
303 return EVP_CipherInit(ctx, cipher, key, iv, 1);
306 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
307 const unsigned char *key, const unsigned char *iv)
309 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
312 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
313 const unsigned char *key, const unsigned char *iv)
315 return EVP_CipherInit(ctx, cipher, key, iv, 0);
318 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
319 const unsigned char *key, const unsigned char *iv)
321 return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
324 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
325 const unsigned char *in, int inl)
329 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
331 i = M_do_cipher(ctx, out, in, inl);
345 if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
347 if(M_do_cipher(ctx,out,in,inl))
359 bl=ctx->cipher->block_size;
360 OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
365 memcpy(&(ctx->buf[i]),in,inl);
373 memcpy(&(ctx->buf[i]),in,j);
374 if(!M_do_cipher(ctx,out,ctx->buf,bl)) return 0;
387 if(!M_do_cipher(ctx,out,in,inl)) return 0;
392 memcpy(ctx->buf,&(in[inl]),i);
397 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
400 ret = EVP_EncryptFinal_ex(ctx, out, outl);
404 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
407 unsigned int i, b, bl;
409 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
411 ret = M_do_cipher(ctx, out, NULL, 0);
419 b=ctx->cipher->block_size;
420 OPENSSL_assert(b <= sizeof ctx->buf);
427 if (ctx->flags & EVP_CIPH_NO_PADDING)
431 EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
441 ret=M_do_cipher(ctx,out,ctx->buf,b);
450 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
451 const unsigned char *in, int inl)
456 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
458 fix_len = M_do_cipher(ctx, out, in, inl);
475 if (ctx->flags & EVP_CIPH_NO_PADDING)
476 return EVP_EncryptUpdate(ctx, out, outl, in, inl);
478 b=ctx->cipher->block_size;
479 OPENSSL_assert(b <= sizeof ctx->final);
483 memcpy(out,ctx->final,b);
491 if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))
494 /* if we have 'decrypted' a multiple of block size, make sure
495 * we have a copy of this last block */
496 if (b > 1 && !ctx->buf_len)
500 memcpy(ctx->final,&out[*outl],b);
511 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
514 ret = EVP_DecryptFinal_ex(ctx, out, outl);
518 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
521 unsigned char pad, padding_good;
524 if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER)
526 int ret = M_do_cipher(ctx, out, NULL, 0);
534 b=(unsigned int)(ctx->cipher->block_size);
535 if (ctx->flags & EVP_CIPH_NO_PADDING)
539 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
547 if (ctx->buf_len || !ctx->final_used)
549 EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
552 OPENSSL_assert(b <= sizeof ctx->final);
555 padding_good = (unsigned char)(~constant_time_is_zero_8(pad));
556 padding_good &= constant_time_ge_8(b, pad);
558 for (i = 1; i < b; ++i)
560 unsigned char is_pad_index = constant_time_lt_8(i, pad);
561 unsigned char pad_byte_good = constant_time_eq_8(ctx->final[b-i-1], pad);
562 padding_good &= constant_time_select_8(is_pad_index, pad_byte_good, 0xff);
566 * At least 1 byte is always padding, so we always write b - 1
567 * bytes to avoid a timing leak. The caller is required to have |b|
568 * bytes space in |out| by the API contract.
570 for (i = 0; i < b - 1; ++i)
571 out[i] = ctx->final[i] & padding_good;
572 /* Safe cast: for a good padding, EVP_MAX_IV_LENGTH >= b >= pad */
573 *outl = padding_good & ((unsigned char)(b - pad));
574 return padding_good & 1;
583 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
587 EVP_CIPHER_CTX_cleanup(ctx);
592 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
595 if (c->cipher != NULL)
597 if(c->cipher->cleanup && !c->cipher->cleanup(c))
599 /* Cleanse cipher context data */
601 OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);
604 OPENSSL_free(c->cipher_data);
606 #ifndef OPENSSL_NO_ENGINE
608 /* The EVP_CIPHER we used belongs to an ENGINE, release the
609 * functional reference we held for this reason. */
610 ENGINE_finish(c->engine);
613 FIPS_cipher_ctx_cleanup(c);
615 memset(c,0,sizeof(EVP_CIPHER_CTX));
619 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
621 if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
622 return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
623 if(c->key_len == keylen) return 1;
624 if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))
629 EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);
633 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
635 if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;
636 else ctx->flags |= EVP_CIPH_NO_PADDING;
640 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
644 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
648 if(!ctx->cipher->ctrl) {
649 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
653 ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
655 EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
661 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
663 if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
664 return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
665 if (RAND_bytes(key, ctx->key_len) <= 0)
670 int EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
672 if ((in == NULL) || (in->cipher == NULL))
674 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,EVP_R_INPUT_NOT_INITIALIZED);
677 #ifndef OPENSSL_NO_ENGINE
678 /* Make sure it's safe to copy a cipher context using an ENGINE */
679 if (in->engine && !ENGINE_init(in->engine))
681 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_ENGINE_LIB);
686 EVP_CIPHER_CTX_cleanup(out);
687 memcpy(out,in,sizeof *out);
689 if (in->cipher_data && in->cipher->ctx_size)
691 out->cipher_data=OPENSSL_malloc(in->cipher->ctx_size);
692 if (!out->cipher_data)
694 EVPerr(EVP_F_EVP_CIPHER_CTX_COPY,ERR_R_MALLOC_FAILURE);
697 memcpy(out->cipher_data,in->cipher_data,in->cipher->ctx_size);
700 if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
701 return in->cipher->ctrl((EVP_CIPHER_CTX *)in, EVP_CTRL_COPY, 0, out);