/* crypto/bio/bf_buff.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/bio.h>

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

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

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

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

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

static int buffer_new(BIO *h);

static int buffer_free(BIO *data);

static long buffer_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp);

#define DEFAULT_BUFFER_SIZE	4096

static BIO_METHOD methods_buffer=

	{

	BIO_TYPE_BUFFER,

	"buffer",

	buffer_write,

	buffer_read,

	buffer_puts,

	buffer_gets,

	buffer_ctrl,

	buffer_new,

	buffer_free,

	buffer_callback_ctrl,

	};

EXPORT_C BIO_METHOD *BIO_f_buffer(void)

	{

	return(&methods_buffer);

	}

static int buffer_new(BIO *bi)

	{

	BIO_F_BUFFER_CTX *ctx;

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

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

	ctx->ibuf=(char *)OPENSSL_malloc(DEFAULT_BUFFER_SIZE);

	if (ctx->ibuf == NULL) { OPENSSL_free(ctx); return(0); }

	ctx->obuf=(char *)OPENSSL_malloc(DEFAULT_BUFFER_SIZE);

	if (ctx->obuf == NULL) { OPENSSL_free(ctx->ibuf); OPENSSL_free(ctx); return(0); }

	ctx->ibuf_size=DEFAULT_BUFFER_SIZE;

	ctx->obuf_size=DEFAULT_BUFFER_SIZE;

	ctx->ibuf_len=0;

	ctx->ibuf_off=0;

	ctx->obuf_len=0;

	ctx->obuf_off=0;

	bi->init=1;

	bi->ptr=(char *)ctx;

	bi->flags=0;

	return(1);

	}

static int buffer_free(BIO *a)

	{

	BIO_F_BUFFER_CTX *b;

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

	b=(BIO_F_BUFFER_CTX *)a->ptr;

	if (b->ibuf != NULL) OPENSSL_free(b->ibuf);

	if (b->obuf != NULL) OPENSSL_free(b->obuf);

	OPENSSL_free(a->ptr);

	a->ptr=NULL;

	a->init=0;

	a->flags=0;

	return(1);

	}

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

	{

	int i,num=0;

	BIO_F_BUFFER_CTX *ctx;

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

	ctx=(BIO_F_BUFFER_CTX *)b->ptr;

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

	num=0;

	BIO_clear_retry_flags(b);

start:

	i=ctx->ibuf_len;

	/* If there is stuff left over, grab it */

	if (i != 0)

		{

		if (i > outl) i=outl;

		memcpy(out,&(ctx->ibuf[ctx->ibuf_off]),i);

		ctx->ibuf_off+=i;

		ctx->ibuf_len-=i;

		num+=i;

		if (outl == i)  return(num);

		outl-=i;

		out+=i;

		}

	/* We may have done a partial read. try to do more.

	 * We have nothing in the buffer.

	 * If we get an error and have read some data, just return it

	 * and let them retry to get the error again.

	 * copy direct to parent address space */

	if (outl > ctx->ibuf_size)

		{

		for (;;)

			{

			i=BIO_read(b->next_bio,out,outl);

			if (i <= 0)

				{

				BIO_copy_next_retry(b);

				if (i < 0) return((num > 0)?num:i);

				if (i == 0) return(num);

				}

			num+=i;

			if (outl == i) return(num);

			out+=i;

			outl-=i;

			}

		}

	/* else */

	/* we are going to be doing some buffering */

	i=BIO_read(b->next_bio,ctx->ibuf,ctx->ibuf_size);

	if (i <= 0)

		{

		BIO_copy_next_retry(b);

		if (i < 0) return((num > 0)?num:i);

		if (i == 0) return(num);

		}

	ctx->ibuf_off=0;

	ctx->ibuf_len=i;

	/* Lets re-read using ourselves :-) */

	goto start;

	}

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

	{

	int i,num=0;

	BIO_F_BUFFER_CTX *ctx;

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

	ctx=(BIO_F_BUFFER_CTX *)b->ptr;

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

	BIO_clear_retry_flags(b);

start:

	i=ctx->obuf_size-(ctx->obuf_len+ctx->obuf_off);

	/* add to buffer and return */

	if (i >= inl)

		{

		memcpy(&(ctx->obuf[ctx->obuf_len]),in,inl);

		ctx->obuf_len+=inl;

		return(num+inl);

		}

	/* else */

	/* stuff already in buffer, so add to it first, then flush */

	if (ctx->obuf_len != 0)

		{

		if (i > 0) /* lets fill it up if we can */

			{

			memcpy(&(ctx->obuf[ctx->obuf_len]),in,i);

			in+=i;

			inl-=i;

			num+=i;

			ctx->obuf_len+=i;

			}

		/* we now have a full buffer needing flushing */

		for (;;)

			{

			i=BIO_write(b->next_bio,&(ctx->obuf[ctx->obuf_off]),

				ctx->obuf_len);

			if (i <= 0)

				{

				BIO_copy_next_retry(b);

				if (i < 0) return((num > 0)?num:i);

				if (i == 0) return(num);

				}

			ctx->obuf_off+=i;

			ctx->obuf_len-=i;

			if (ctx->obuf_len == 0) break;

			}

		}

	/* we only get here if the buffer has been flushed and we

	 * still have stuff to write */

	ctx->obuf_off=0;

	/* we now have inl bytes to write */

	while (inl >= ctx->obuf_size)

		{

		i=BIO_write(b->next_bio,in,inl);

		if (i <= 0)

			{

			BIO_copy_next_retry(b);

			if (i < 0) return((num > 0)?num:i);

			if (i == 0) return(num);

			}

		num+=i;

		in+=i;

		inl-=i;

		if (inl == 0) return(num);

		}

	/* copy the rest into the buffer since we have only a small 

	 * amount left */

	goto start;

	}

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

	{

	BIO *dbio;

	BIO_F_BUFFER_CTX *ctx;

	long ret=1;

	char *p1,*p2;

	int r,i,*ip;

	int ibs,obs;

	ctx=(BIO_F_BUFFER_CTX *)b->ptr;

	switch (cmd)

		{

	case BIO_CTRL_RESET:

		ctx->ibuf_off=0;

		ctx->ibuf_len=0;

		ctx->obuf_off=0;

		ctx->obuf_len=0;

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

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

		break;

	case BIO_CTRL_INFO:

		ret=(long)ctx->obuf_len;

		break;

	case BIO_C_GET_BUFF_NUM_LINES:

		ret=0;

		p1=ctx->ibuf;

		for (i=ctx->ibuf_off; i<ctx->ibuf_len; i++)

			{

			if (p1[i] == '\n') ret++;

			}

		break;

	case BIO_CTRL_WPENDING:

		ret=(long)ctx->obuf_len;

		if (ret == 0)

			{

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

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

			}

		break;

	case BIO_CTRL_PENDING:

		ret=(long)ctx->ibuf_len;

		if (ret == 0)

			{

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

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

			}

		break;

	case BIO_C_SET_BUFF_READ_DATA:

		if (num > ctx->ibuf_size)

			{

			p1=OPENSSL_malloc((int)num);

			if (p1 == NULL) goto malloc_error;

			if (ctx->ibuf != NULL) OPENSSL_free(ctx->ibuf);

			ctx->ibuf=p1;

			}

		ctx->ibuf_off=0;

		ctx->ibuf_len=(int)num;

		memcpy(ctx->ibuf,ptr,(int)num);

		ret=1;

		break;

	case BIO_C_SET_BUFF_SIZE:

		if (ptr != NULL)

			{

			ip=(int *)ptr;

			if (*ip == 0)

				{

				ibs=(int)num;

				obs=ctx->obuf_size;

				}

			else /* if (*ip == 1) */

				{

				ibs=ctx->ibuf_size;

				obs=(int)num;

				}

			}

		else

			{

			ibs=(int)num;

			obs=(int)num;

			}

		p1=ctx->ibuf;

		p2=ctx->obuf;

		if ((ibs > DEFAULT_BUFFER_SIZE) && (ibs != ctx->ibuf_size))

			{

			p1=(char *)OPENSSL_malloc((int)num);

			if (p1 == NULL) goto malloc_error;

			}

		if ((obs > DEFAULT_BUFFER_SIZE) && (obs != ctx->obuf_size))

			{

			p2=(char *)OPENSSL_malloc((int)num);

			if (p2 == NULL)

				{

				if (p1 != ctx->ibuf) OPENSSL_free(p1);

				goto malloc_error;

				}

			}

		if (ctx->ibuf != p1)

			{

			OPENSSL_free(ctx->ibuf);

			ctx->ibuf=p1;

			ctx->ibuf_off=0;

			ctx->ibuf_len=0;

			ctx->ibuf_size=ibs;

			}

		if (ctx->obuf != p2)

			{

			OPENSSL_free(ctx->obuf);

			ctx->obuf=p2;

			ctx->obuf_off=0;

			ctx->obuf_len=0;

			ctx->obuf_size=obs;

			}

		break;

	case BIO_C_DO_STATE_MACHINE:

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

		BIO_clear_retry_flags(b);

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

		BIO_copy_next_retry(b);

		break;

	case BIO_CTRL_FLUSH:

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

		if (ctx->obuf_len <= 0)

			{

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

			break;

			}

		for (;;)

			{

			BIO_clear_retry_flags(b);

			if (ctx->obuf_len > ctx->obuf_off)

				{

				r=BIO_write(b->next_bio,

					&(ctx->obuf[ctx->obuf_off]),

					ctx->obuf_len-ctx->obuf_off);

#if 0

fprintf(stderr,"FLUSH [%3d] %3d -> %3d\n",ctx->obuf_off,ctx->obuf_len-ctx->obuf_off,r);

#endif

				BIO_copy_next_retry(b);

				if (r <= 0) return((long)r);

				ctx->obuf_off+=r;

				}

			else

				{

				ctx->obuf_len=0;

				ctx->obuf_off=0;

				ret=1;

				break;

				}

			}

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

		break;

	case BIO_CTRL_DUP:

		dbio=(BIO *)ptr;

		if (	!BIO_set_read_buffer_size(dbio,ctx->ibuf_size) ||

			!BIO_set_write_buffer_size(dbio,ctx->obuf_size))

			ret=0;

		break;

	default:

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

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

		break;

		}

	return(ret);

malloc_error:

	BIOerr(BIO_F_BUFFER_CTRL,ERR_R_MALLOC_FAILURE);

	return(0);

	}

static long buffer_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);

	}

static int buffer_gets(BIO *b, char *buf, int size)

	{

	BIO_F_BUFFER_CTX *ctx;

	int num=0,i,flag;

	char *p;

	ctx=(BIO_F_BUFFER_CTX *)b->ptr;

	size--; /* reserve space for a '\0' */

	BIO_clear_retry_flags(b);

	for (;;)

		{

		if (ctx->ibuf_len > 0)

			{

			p= &(ctx->ibuf[ctx->ibuf_off]);

			flag=0;

			for (i=0; (i<ctx->ibuf_len) && (i<size); i++)

				{

				*(buf++)=p[i];

				if (p[i] == '\n')

					{

					flag=1;

					i++;

					break;

					}

				}

			num+=i;

			size-=i;

			ctx->ibuf_len-=i;

			ctx->ibuf_off+=i;

			if (flag || size == 0)

				{

				*buf='\0';

				return(num);

				}

			}

		else	/* read another chunk */

			{

			i=BIO_read(b->next_bio,ctx->ibuf,ctx->ibuf_size);

			if (i <= 0)

				{

				BIO_copy_next_retry(b);

				*buf='\0';

				if (i < 0) return((num > 0)?num:i);

				if (i == 0) return(num);

				}

			ctx->ibuf_len=i;

			ctx->ibuf_off=0;

			}

		}

	}

static int buffer_puts(BIO *b, const char *str)

	{

	return(buffer_write(b,str,strlen(str)));

	}