/* 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.] */#include <stdio.h>#include <errno.h>#include "cryptlib.h"#include <openssl/buffer.h>#include <openssl/evp.h>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_LENGTHtypedef 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;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,	};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);	}*/void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, unsigned char *k,	     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);	}