openssl/crypto/evp/evp_enc.c
2008-09-15 22:32:23 +00:00

440 lines
11 KiB
C

/* crypto/evp/evp_enc.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/rand.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif
#include "evp_locl.h"
#ifdef OPENSSL_FIPS
#define M_do_cipher(ctx, out, in, inl) \
EVP_Cipher(ctx,out,in,inl)
#else
#define M_do_cipher(ctx, out, in, inl) \
ctx->cipher->do_cipher(ctx,out,in,inl)
#endif
const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;
EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
{
EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);
if (ctx)
EVP_CIPHER_CTX_init(ctx);
return ctx;
}
int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
const unsigned char *key, const unsigned char *iv, int enc)
{
if (cipher)
EVP_CIPHER_CTX_init(ctx);
return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc);
}
int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
if (ctx->encrypt)
return EVP_EncryptUpdate(ctx,out,outl,in,inl);
else return EVP_DecryptUpdate(ctx,out,outl,in,inl);
}
int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
if (ctx->encrypt)
return EVP_EncryptFinal_ex(ctx,out,outl);
else return EVP_DecryptFinal_ex(ctx,out,outl);
}
int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
if (ctx->encrypt)
return EVP_EncryptFinal(ctx,out,outl);
else return EVP_DecryptFinal(ctx,out,outl);
}
int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
const unsigned char *key, const unsigned char *iv)
{
return EVP_CipherInit(ctx, cipher, key, iv, 1);
}
int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
const unsigned char *key, const unsigned char *iv)
{
return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
}
int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
const unsigned char *key, const unsigned char *iv)
{
return EVP_CipherInit(ctx, cipher, key, iv, 0);
}
int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
const unsigned char *key, const unsigned char *iv)
{
return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
}
int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
int i,j,bl;
if (inl <= 0)
{
*outl = 0;
return inl == 0;
}
if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
{
if(M_do_cipher(ctx,out,in,inl))
{
*outl=inl;
return 1;
}
else
{
*outl=0;
return 0;
}
}
i=ctx->buf_len;
bl=ctx->cipher->block_size;
OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
if (i != 0)
{
if (i+inl < bl)
{
memcpy(&(ctx->buf[i]),in,inl);
ctx->buf_len+=inl;
*outl=0;
return 1;
}
else
{
j=bl-i;
memcpy(&(ctx->buf[i]),in,j);
if(!M_do_cipher(ctx,out,ctx->buf,bl)) return 0;
inl-=j;
in+=j;
out+=bl;
*outl=bl;
}
}
else
*outl = 0;
i=inl&(bl-1);
inl-=i;
if (inl > 0)
{
if(!M_do_cipher(ctx,out,in,inl)) return 0;
*outl+=inl;
}
if (i != 0)
memcpy(ctx->buf,&(in[inl]),i);
ctx->buf_len=i;
return 1;
}
int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int ret;
ret = EVP_EncryptFinal_ex(ctx, out, outl);
return ret;
}
int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int n,ret;
unsigned int i, b, bl;
b=ctx->cipher->block_size;
OPENSSL_assert(b <= sizeof ctx->buf);
if (b == 1)
{
*outl=0;
return 1;
}
bl=ctx->buf_len;
if (ctx->flags & EVP_CIPH_NO_PADDING)
{
if(bl)
{
EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
return 0;
}
*outl = 0;
return 1;
}
n=b-bl;
for (i=bl; i<b; i++)
ctx->buf[i]=n;
ret=M_do_cipher(ctx,out,ctx->buf,b);
if(ret)
*outl=b;
return ret;
}
int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
const unsigned char *in, int inl)
{
int fix_len;
unsigned int b;
if (inl <= 0)
{
*outl = 0;
return inl == 0;
}
if (ctx->flags & EVP_CIPH_NO_PADDING)
return EVP_EncryptUpdate(ctx, out, outl, in, inl);
b=ctx->cipher->block_size;
OPENSSL_assert(b <= sizeof ctx->final);
if(ctx->final_used)
{
memcpy(out,ctx->final,b);
out+=b;
fix_len = 1;
}
else
fix_len = 0;
if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))
return 0;
/* if we have 'decrypted' a multiple of block size, make sure
* we have a copy of this last block */
if (b > 1 && !ctx->buf_len)
{
*outl-=b;
ctx->final_used=1;
memcpy(ctx->final,&out[*outl],b);
}
else
ctx->final_used = 0;
if (fix_len)
*outl += b;
return 1;
}
int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int ret;
ret = EVP_DecryptFinal_ex(ctx, out, outl);
return ret;
}
int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
int i,n;
unsigned int b;
*outl=0;
b=ctx->cipher->block_size;
if (ctx->flags & EVP_CIPH_NO_PADDING)
{
if(ctx->buf_len)
{
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
return 0;
}
*outl = 0;
return 1;
}
if (b > 1)
{
if (ctx->buf_len || !ctx->final_used)
{
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
return(0);
}
OPENSSL_assert(b <= sizeof ctx->final);
n=ctx->final[b-1];
if (n == 0 || n > (int)b)
{
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);
return(0);
}
for (i=0; i<n; i++)
{
if (ctx->final[--b] != n)
{
EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);
return(0);
}
}
n=ctx->cipher->block_size-n;
for (i=0; i<n; i++)
out[i]=ctx->final[i];
*outl=n;
}
else
*outl=0;
return(1);
}
void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
{
if (ctx)
{
EVP_CIPHER_CTX_cleanup(ctx);
OPENSSL_free(ctx);
}
}
int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
{
if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
if(c->key_len == keylen) return 1;
if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))
{
c->key_len = keylen;
return 1;
}
EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);
return 0;
}
int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
{
if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;
else ctx->flags |= EVP_CIPH_NO_PADDING;
return 1;
}
int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
{
if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
if (RAND_bytes(key, ctx->key_len) <= 0)
return 0;
return 1;
}
#ifndef OPENSSL_NO_ENGINE
#ifdef OPENSSL_FIPS
static int do_evp_enc_engine_full(EVP_CIPHER_CTX *ctx, const EVP_CIPHER **pcipher, ENGINE *impl)
{
if(impl)
{
if (!ENGINE_init(impl))
{
EVPerr(EVP_F_DO_EVP_ENC_ENGINE_FULL, EVP_R_INITIALIZATION_ERROR);
return 0;
}
}
else
/* Ask if an ENGINE is reserved for this job */
impl = ENGINE_get_cipher_engine((*pcipher)->nid);
if(impl)
{
/* There's an ENGINE for this job ... (apparently) */
const EVP_CIPHER *c = ENGINE_get_cipher(impl, (*pcipher)->nid);
if(!c)
{
/* One positive side-effect of US's export
* control history, is that we should at least
* be able to avoid using US mispellings of
* "initialisation"? */
EVPerr(EVP_F_DO_EVP_ENC_ENGINE_FULL, EVP_R_INITIALIZATION_ERROR);
return 0;
}
/* We'll use the ENGINE's private cipher definition */
*pcipher = c;
/* Store the ENGINE functional reference so we know
* 'cipher' came from an ENGINE and we need to release
* it when done. */
ctx->engine = impl;
}
else
ctx->engine = NULL;
return 1;
}
void int_EVP_CIPHER_init_engine_callbacks(void)
{
int_EVP_CIPHER_set_engine_callbacks(
ENGINE_finish, do_evp_enc_engine_full);
}
#endif
#endif