/* 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"

 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;

 EXPORT_C void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)

 	{

 	memset(ctx,0,sizeof(EVP_CIPHER_CTX));

 	/* ctx->cipher=NULL; */

 	}

 EXPORT_C 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;

 	}

 EXPORT_C 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);

 	}

 EXPORT_C int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,

 	     const unsigned char *key, const unsigned char *iv, int enc)

 	{

 	if (enc == -1)

 		enc = ctx->encrypt;

 	else

 		{

 		if (enc)

 			enc = 1;

 		ctx->encrypt = enc;

 		}

 #ifndef OPENSSL_NO_ENGINE

 	/* Whether it's nice or not, "Inits" can be used on "Final"'d contexts

 	 * so this context may already have an ENGINE! Try to avoid releasing

 	 * the previous handle, re-querying for an ENGINE, and having a

 	 * reinitialisation, when it may all be unecessary. */

 	if (ctx->engine && ctx->cipher && (!cipher ||

 			(cipher && (cipher->nid == ctx->cipher->nid))))

 		goto skip_to_init;

 #endif

 	if (cipher)

 		{

 		/* Ensure a context left lying around from last time is cleared

 		 * (the previous check attempted to avoid this if the same

 		 * ENGINE and EVP_CIPHER could be used). */

 		EVP_CIPHER_CTX_cleanup(ctx);

 		/* Restore encrypt field: it is zeroed by cleanup */

 		ctx->encrypt = enc;

 #ifndef OPENSSL_NO_ENGINE

 		if(impl)

 			{

 			if (!ENGINE_init(impl))

 				{

 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);

 				return 0;

 				}

 			}

 		else

 			/* Ask if an ENGINE is reserved for this job */

 			impl = ENGINE_get_cipher_engine(cipher->nid);

 		if(impl)

 			{

 			/* There's an ENGINE for this job ... (apparently) */

 			const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->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_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);

 				return 0;

 				}

 			/* We'll use the ENGINE's private cipher definition */

 			cipher = 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;

 #endif

 		ctx->cipher=cipher;

 		if (ctx->cipher->ctx_size)

 			{

 			ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);

 			if (!ctx->cipher_data)

 				{

 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);

 				return 0;

 				}

 			}

 		else

 			{

 			ctx->cipher_data = NULL;

 			}

 		ctx->key_len = cipher->key_len;

 		ctx->flags = 0;

 		if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)

 			{

 			if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))

 				{

 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);

 				return 0;

 				}

 			}

 		}

 	else if(!ctx->cipher)

 		{

 		EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);

 		return 0;

 		}

 #ifndef OPENSSL_NO_ENGINE

 skip_to_init:

 #endif

 	/* we assume block size is a power of 2 in *cryptUpdate */

 	OPENSSL_assert(ctx->cipher->block_size == 1

 	    || ctx->cipher->block_size == 8

 	    || ctx->cipher->block_size == 16);

 	if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {

 		switch(EVP_CIPHER_CTX_mode(ctx)) {

 			case EVP_CIPH_STREAM_CIPHER:

 			case EVP_CIPH_ECB_MODE:

 			break;

 			case EVP_CIPH_CFB_MODE:

 			case EVP_CIPH_OFB_MODE:

 			ctx->num = 0;

 			case EVP_CIPH_CBC_MODE:

 			OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=

 					(int)sizeof(ctx->iv));

 			if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));

 			memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));

 			break;

 			default:

 			return 0;

 			break;

 		}

 	}

 	if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {

 		if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;

 	}

 	ctx->buf_len=0;

 	ctx->final_used=0;

 	ctx->block_mask=ctx->cipher->block_size-1;

 	return 1;

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}

 EXPORT_C 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);

 	}

 EXPORT_C int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,

 	     const unsigned char *in, int inl)

 	{

 	int i,j,bl;

 	OPENSSL_assert(inl > 0);

 	if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)

 		{

 		if(ctx->cipher->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(!ctx->cipher->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(!ctx->cipher->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;

 	}

 EXPORT_C int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

 	{

 	int ret;

 	ret = EVP_EncryptFinal_ex(ctx, out, outl);

 	return ret;

 	}

 EXPORT_C 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=ctx->cipher->do_cipher(ctx,out,ctx->buf,b);

 	if(ret)

 		*outl=b;

 	return ret;

 	}

 EXPORT_C 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 1;

 		}

 	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;

 	}

 EXPORT_C int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

 	{

 	int ret;

 	ret = EVP_DecryptFinal_ex(ctx, out, outl);

 	return ret;

 	}

 EXPORT_C 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);

 	}

 EXPORT_C void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)

 	{

 	if (ctx)

 		{

 		EVP_CIPHER_CTX_cleanup(ctx);

 		OPENSSL_free(ctx);

 		}

 	}

 EXPORT_C int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)

 	{

 	if (c->cipher != NULL)

 		{

 		if(c->cipher->cleanup && !c->cipher->cleanup(c))

 			return 0;

 		/* Cleanse cipher context data */

 		if (c->cipher_data)

 			OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);

 		}

 	if (c->cipher_data)

 		OPENSSL_free(c->cipher_data);

 #ifndef OPENSSL_NO_ENGINE

 	if (c->engine)

 		/* The EVP_CIPHER we used belongs to an ENGINE, release the

 		 * functional reference we held for this reason. */

 		ENGINE_finish(c->engine);

 #endif

 	memset(c,0,sizeof(EVP_CIPHER_CTX));

 	return 1;

 	}

 EXPORT_C 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;

 	}

 EXPORT_C 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;

 	}

 EXPORT_C int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)

 {

 	int ret;

 	if(!ctx->cipher) {

 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);

 		return 0;

 	}

 	if(!ctx->cipher->ctrl) {

 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);

 		return 0;

 	}

 	ret = ctx->cipher->ctrl(ctx, type, arg, ptr);

 	if(ret == -1) {

 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);

 		return 0;

 	}

 	return ret;

 }

 EXPORT_C 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;

 	}