/* crypto/evp/bio_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.]

  */

 /*

  © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

  */

 #include <stdio.h>

 #include <errno.h>

 #include "cryptlib.h"

 #include <openssl/buffer.h>

 #include <openssl/evp.h>

 #if (defined(SYMBIAN) && (defined(__WINSCW__) || defined(__WINS__)))

 #include "libcrypto_wsd_macros.h"

 #include "libcrypto_wsd.h"

 #endif

 static int enc_write(BIO *h, const char *buf, int num);

 static int enc_read(BIO *h, char *buf, int size);

 /*static int enc_puts(BIO *h, const char *str); */

 /*static int enc_gets(BIO *h, char *str, int size); */

 static long enc_ctrl(BIO *h, int cmd, long arg1, void *arg2);

 static int enc_new(BIO *h);

 static int enc_free(BIO *data);

 static long enc_callback_ctrl(BIO *h, int cmd, bio_info_cb *fps);

 #define ENC_BLOCK_SIZE	(1024*4)

 #define BUF_OFFSET	(EVP_MAX_BLOCK_LENGTH*2)

 typedef struct enc_struct

 	{

 	int buf_len;

 	int buf_off;

 	int cont;		/* <= 0 when finished */

 	int finished;

 	int ok;			/* bad decrypt */

 	EVP_CIPHER_CTX cipher;

 	/* buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate

 	 * can return up to a block more data than is presented to it

 	 */

 	char buf[ENC_BLOCK_SIZE+BUF_OFFSET+2];

 	} BIO_ENC_CTX;

 #ifndef EMULATOR

 static BIO_METHOD methods_enc=

 	{

 	BIO_TYPE_CIPHER,"cipher",

 	enc_write,

 	enc_read,

 	NULL, /* enc_puts, */

 	NULL, /* enc_gets, */

 	enc_ctrl,

 	enc_new,

 	enc_free,

 	enc_callback_ctrl,

 	};

 #else

 GET_STATIC_VAR_FROM_TLS(methods_enc,bio_enc,BIO_METHOD)

 #define methods_enc (*GET_WSD_VAR_NAME(methods_enc,bio_enc, s)())

 const BIO_METHOD temp_s_methods_enc=

 	{

 	BIO_TYPE_CIPHER,"cipher",

 	enc_write,

 	enc_read,

 	NULL, /* enc_puts, */

 	NULL, /* enc_gets, */

 	enc_ctrl,

 	enc_new,

 	enc_free,

 	enc_callback_ctrl,

 	};

 #endif	

 EXPORT_C BIO_METHOD *BIO_f_cipher(void)

 	{

 	return(&methods_enc);

 	}

 static int enc_new(BIO *bi)

 	{

 	BIO_ENC_CTX *ctx;

 	ctx=(BIO_ENC_CTX *)OPENSSL_malloc(sizeof(BIO_ENC_CTX));

 	if (ctx == NULL) return(0);

 	EVP_CIPHER_CTX_init(&ctx->cipher);

 	ctx->buf_len=0;

 	ctx->buf_off=0;

 	ctx->cont=1;

 	ctx->finished=0;

 	ctx->ok=1;

 	bi->init=0;

 	bi->ptr=(char *)ctx;

 	bi->flags=0;

 	return(1);

 	}

 static int enc_free(BIO *a)

 	{

 	BIO_ENC_CTX *b;

 	if (a == NULL) return(0);

 	b=(BIO_ENC_CTX *)a->ptr;

 	EVP_CIPHER_CTX_cleanup(&(b->cipher));

 	OPENSSL_cleanse(a->ptr,sizeof(BIO_ENC_CTX));

 	OPENSSL_free(a->ptr);

 	a->ptr=NULL;

 	a->init=0;

 	a->flags=0;

 	return(1);

 	}

 static int enc_read(BIO *b, char *out, int outl)

 	{

 	int ret=0,i;

 	BIO_ENC_CTX *ctx;

 	if (out == NULL) return(0);

 	ctx=(BIO_ENC_CTX *)b->ptr;

 	if ((ctx == NULL) || (b->next_bio == NULL)) return(0);

 	/* First check if there are bytes decoded/encoded */

 	if (ctx->buf_len > 0)

 		{

 		i=ctx->buf_len-ctx->buf_off;

 		if (i > outl) i=outl;

 		memcpy(out,&(ctx->buf[ctx->buf_off]),i);

 		ret=i;

 		out+=i;

 		outl-=i;

 		ctx->buf_off+=i;

 		if (ctx->buf_len == ctx->buf_off)

 			{

 			ctx->buf_len=0;

 			ctx->buf_off=0;

 			}

 		}

 	/* At this point, we have room of outl bytes and an empty

 	 * buffer, so we should read in some more. */

 	while (outl > 0)

 		{

 		if (ctx->cont <= 0) break;

 		/* read in at IV offset, read the EVP_Cipher

 		 * documentation about why */

 		i=BIO_read(b->next_bio,&(ctx->buf[BUF_OFFSET]),ENC_BLOCK_SIZE);

 		if (i <= 0)

 			{

 			/* Should be continue next time we are called? */

 			if (!BIO_should_retry(b->next_bio))

 				{

 				ctx->cont=i;

 				i=EVP_CipherFinal_ex(&(ctx->cipher),

 					(unsigned char *)ctx->buf,

 					&(ctx->buf_len));

 				ctx->ok=i;

 				ctx->buf_off=0;

 				}

 			else 

 				{

 				ret=(ret == 0)?i:ret;

 				break;

 				}

 			}

 		else

 			{

 			EVP_CipherUpdate(&(ctx->cipher),

 				(unsigned char *)ctx->buf,&ctx->buf_len,

 				(unsigned char *)&(ctx->buf[BUF_OFFSET]),i);

 			ctx->cont=1;

 			/* Note: it is possible for EVP_CipherUpdate to

 			 * decrypt zero bytes because this is or looks like

 			 * the final block: if this happens we should retry

 			 * and either read more data or decrypt the final

 			 * block

 			 */

 			if(ctx->buf_len == 0) continue;

 			}

 		if (ctx->buf_len <= outl)

 			i=ctx->buf_len;

 		else

 			i=outl;

 		if (i <= 0) break;

 		memcpy(out,ctx->buf,i);

 		ret+=i;

 		ctx->buf_off=i;

 		outl-=i;

 		out+=i;

 		}

 	BIO_clear_retry_flags(b);

 	BIO_copy_next_retry(b);

 	return((ret == 0)?ctx->cont:ret);

 	}

 static int enc_write(BIO *b, const char *in, int inl)

 	{

 	int ret=0,n,i;

 	BIO_ENC_CTX *ctx;

 	ctx=(BIO_ENC_CTX *)b->ptr;

 	ret=inl;

 	BIO_clear_retry_flags(b);

 	n=ctx->buf_len-ctx->buf_off;

 	while (n > 0)

 		{

 		i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);

 		if (i <= 0)

 			{

 			BIO_copy_next_retry(b);

 			return(i);

 			}

 		ctx->buf_off+=i;

 		n-=i;

 		}

 	/* at this point all pending data has been written */

 	if ((in == NULL) || (inl <= 0)) return(0);

 	ctx->buf_off=0;

 	while (inl > 0)

 		{

 		n=(inl > ENC_BLOCK_SIZE)?ENC_BLOCK_SIZE:inl;

 		EVP_CipherUpdate(&(ctx->cipher),

 			(unsigned char *)ctx->buf,&ctx->buf_len,

 			(unsigned char *)in,n);

 		inl-=n;

 		in+=n;

 		ctx->buf_off=0;

 		n=ctx->buf_len;

 		while (n > 0)

 			{

 			i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);

 			if (i <= 0)

 				{

 				BIO_copy_next_retry(b);

 				return (ret == inl) ? i : ret - inl;

 				}

 			n-=i;

 			ctx->buf_off+=i;

 			}

 		ctx->buf_len=0;

 		ctx->buf_off=0;

 		}

 	BIO_copy_next_retry(b);

 	return(ret);

 	}

 static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)

 	{

 	BIO *dbio;

 	BIO_ENC_CTX *ctx,*dctx;

 	long ret=1;

 	int i;

 	EVP_CIPHER_CTX **c_ctx;

 	ctx=(BIO_ENC_CTX *)b->ptr;

 	switch (cmd)

 		{

 	case BIO_CTRL_RESET:

 		ctx->ok=1;

 		ctx->finished=0;

 		EVP_CipherInit_ex(&(ctx->cipher),NULL,NULL,NULL,NULL,

 			ctx->cipher.encrypt);

 		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		break;

 	case BIO_CTRL_EOF:	/* More to read */

 		if (ctx->cont <= 0)

 			ret=1;

 		else

 			ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		break;

 	case BIO_CTRL_WPENDING:

 		ret=ctx->buf_len-ctx->buf_off;

 		if (ret <= 0)

 			ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		break;

 	case BIO_CTRL_PENDING: /* More to read in buffer */

 		ret=ctx->buf_len-ctx->buf_off;

 		if (ret <= 0)

 			ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		break;

 	case BIO_CTRL_FLUSH:

 		/* do a final write */

 again:

 		while (ctx->buf_len != ctx->buf_off)

 			{

 			i=enc_write(b,NULL,0);

 			if (i < 0)

 				return i;

 			}

 		if (!ctx->finished)

 			{

 			ctx->finished=1;

 			ctx->buf_off=0;

 			ret=EVP_CipherFinal_ex(&(ctx->cipher),

 				(unsigned char *)ctx->buf,

 				&(ctx->buf_len));

 			ctx->ok=(int)ret;

 			if (ret <= 0) break;

 			/* push out the bytes */

 			goto again;

 			}

 		/* Finally flush the underlying BIO */

 		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		break;

 	case BIO_C_GET_CIPHER_STATUS:

 		ret=(long)ctx->ok;

 		break;

 	case BIO_C_DO_STATE_MACHINE:

 		BIO_clear_retry_flags(b);

 		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		BIO_copy_next_retry(b);

 		break;

 	case BIO_C_GET_CIPHER_CTX:

 		c_ctx=(EVP_CIPHER_CTX **)ptr;

 		(*c_ctx)= &(ctx->cipher);

 		b->init=1;

 		break;

 	case BIO_CTRL_DUP:

 		dbio=(BIO *)ptr;

 		dctx=(BIO_ENC_CTX *)dbio->ptr;

 		memcpy(&(dctx->cipher),&(ctx->cipher),sizeof(ctx->cipher));

 		dbio->init=1;

 		break;

 	default:

 		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);

 		break;

 		}

 	return(ret);

 	}

 static long enc_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)

 	{

 	long ret=1;

 	if (b->next_bio == NULL) return(0);

 	switch (cmd)

 		{

 	default:

 		ret=BIO_callback_ctrl(b->next_bio,cmd,fp);

 		break;

 		}

 	return(ret);

 	}

 /*

 void BIO_set_cipher_ctx(b,c)

 BIO *b;

 EVP_CIPHER_ctx *c;

 	{

 	if (b == NULL) return;

 	if ((b->callback != NULL) &&

 		(b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))

 		return;

 	b->init=1;

 	ctx=(BIO_ENC_CTX *)b->ptr;

 	memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));

 	if (b->callback != NULL)

 		b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);

 	}

 */

 EXPORT_C void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, const unsigned char *k,

 	     const unsigned char *i, int e)

 	{

 	BIO_ENC_CTX *ctx;

 	if (b == NULL) return;

 	if ((b->callback != NULL) &&

 		(b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,0L) <= 0))

 		return;

 	b->init=1;

 	ctx=(BIO_ENC_CTX *)b->ptr;

 	EVP_CipherInit_ex(&(ctx->cipher),c,NULL, k,i,e);

 	if (b->callback != NULL)

 		b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,1L);

 	}