/* crypto/evp/bio_b64.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 b64_write(BIO *h, const char *buf, int num);

static int b64_read(BIO *h, char *buf, int size);

/*static int b64_puts(BIO *h, const char *str); */

/*static int b64_gets(BIO *h, char *str, int size); */

static long b64_ctrl(BIO *h, int cmd, long arg1, void *arg2);

static int b64_new(BIO *h);

static int b64_free(BIO *data);

static long b64_callback_ctrl(BIO *h,int cmd,bio_info_cb *fp);

#define B64_BLOCK_SIZE	1024

#define B64_BLOCK_SIZE2	768

#define B64_NONE	0

#define B64_ENCODE	1

#define B64_DECODE	2

typedef struct b64_struct

	{

	/*BIO *bio; moved to the BIO structure */

	int buf_len;

	int buf_off;

	int tmp_len;		/* used to find the start when decoding */

	int tmp_nl;		/* If true, scan until '\n' */

	int encode;

	int start;		/* have we started decoding yet? */

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

	EVP_ENCODE_CTX base64;

	char buf[EVP_ENCODE_LENGTH(B64_BLOCK_SIZE)+10];

	char tmp[B64_BLOCK_SIZE];

	} BIO_B64_CTX;

#ifndef EMULATOR

static BIO_METHOD methods_b64=

	{

	BIO_TYPE_BASE64,"base64 encoding",

	b64_write,

	b64_read,

	NULL, /* b64_puts, */

	NULL, /* b64_gets, */

	b64_ctrl,

	b64_new,

	b64_free,

	b64_callback_ctrl,

	};

#else

GET_STATIC_VAR_FROM_TLS(methods_b64,bio_b64,BIO_METHOD)

#define methods_b64 (*GET_WSD_VAR_NAME(methods_b64,bio_b64, s)())

const BIO_METHOD temp_s_methods_b64=

	{

	BIO_TYPE_BASE64,"base64 encoding",

	b64_write,

	b64_read,

	NULL, /* b64_puts, */

	NULL, /* b64_gets, */

	b64_ctrl,

	b64_new,

	b64_free,

	b64_callback_ctrl,

	};

#endif

EXPORT_C BIO_METHOD *BIO_f_base64(void)

	{

	return(&methods_b64);

	}

static int b64_new(BIO *bi)

	{

	BIO_B64_CTX *ctx;

	ctx=(BIO_B64_CTX *)OPENSSL_malloc(sizeof(BIO_B64_CTX));

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

	ctx->buf_len=0;

	ctx->tmp_len=0;

	ctx->tmp_nl=0;

	ctx->buf_off=0;

	ctx->cont=1;

	ctx->start=1;

	ctx->encode=0;

	bi->init=1;

	bi->ptr=(char *)ctx;

	bi->flags=0;

	return(1);

	}

static int b64_free(BIO *a)

	{

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

	OPENSSL_free(a->ptr);

	a->ptr=NULL;

	a->init=0;

	a->flags=0;

	return(1);

	}

static int b64_read(BIO *b, char *out, int outl)

	{

	int ret=0,i,ii,j,k,x,n,num,ret_code=0;

	BIO_B64_CTX *ctx;

	unsigned char *p,*q;

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

	ctx=(BIO_B64_CTX *)b->ptr;

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

	if (ctx->encode != B64_DECODE)

		{

		ctx->encode=B64_DECODE;

		ctx->buf_len=0;

		ctx->buf_off=0;

		ctx->tmp_len=0;

		EVP_DecodeInit(&(ctx->base64));

		}

	/* 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;

		OPENSSL_assert(ctx->buf_off+i < (int)sizeof(ctx->buf));

		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. */

	ret_code=0;

	while (outl > 0)

		{

		if (ctx->cont <= 0)

			break;

		i=BIO_read(b->next_bio,&(ctx->tmp[ctx->tmp_len]),

			B64_BLOCK_SIZE-ctx->tmp_len);

		if (i <= 0)

			{

			ret_code=i;

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

			if (!BIO_should_retry(b->next_bio))

				{

				ctx->cont=i;

				/* If buffer empty break */

				if(ctx->tmp_len == 0)

					break;

				/* Fall through and process what we have */

				else

					i = 0;

				}

			/* else we retry and add more data to buffer */

			else

				break;

			}

		i+=ctx->tmp_len;

		ctx->tmp_len = i;

		/* We need to scan, a line at a time until we

		 * have a valid line if we are starting. */

		if (ctx->start && (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL))

			{

			/* ctx->start=1; */

			ctx->tmp_len=0;

			}

		else if (ctx->start)

			{

			q=p=(unsigned char *)ctx->tmp;

			for (j=0; j<i; j++)

				{

				if (*(q++) != '\n') continue;

				/* due to a previous very long line,

				 * we need to keep on scanning for a '\n'

				 * before we even start looking for

				 * base64 encoded stuff. */

				if (ctx->tmp_nl)

					{

					p=q;

					ctx->tmp_nl=0;

					continue;

					}

				k=EVP_DecodeUpdate(&(ctx->base64),

					(unsigned char *)ctx->buf,

					&num,p,q-p);

				if ((k <= 0) && (num == 0) && (ctx->start))

					EVP_DecodeInit(&ctx->base64);

				else 

					{

					if (p != (unsigned char *)

						&(ctx->tmp[0]))

						{

						i-=(p- (unsigned char *)

							&(ctx->tmp[0]));

						for (x=0; x < i; x++)

							ctx->tmp[x]=p[x];

						}

					EVP_DecodeInit(&ctx->base64);

					ctx->start=0;

					break;

					}

				p=q;

				}

			/* we fell off the end without starting */

			if (j == i)

				{

				/* Is this is one long chunk?, if so, keep on

				 * reading until a new line. */

				if (p == (unsigned char *)&(ctx->tmp[0]))

					{

					/* Check buffer full */

					if (i == B64_BLOCK_SIZE)

						{

						ctx->tmp_nl=1;

						ctx->tmp_len=0;

						}

					}

				else if (p != q) /* finished on a '\n' */

					{

					n=q-p;

					for (ii=0; ii<n; ii++)

						ctx->tmp[ii]=p[ii];

					ctx->tmp_len=n;

					}

				/* else finished on a '\n' */

				continue;

				}

			else

				ctx->tmp_len=0;

			}

		/* If buffer isn't full and we can retry then

		 * restart to read in more data.

		 */

		else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0))

			continue;

		if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)

			{

			int z,jj;

			jj=(i>>2)<<2;

			z=EVP_DecodeBlock((unsigned char *)ctx->buf,

				(unsigned char *)ctx->tmp,jj);

			if (jj > 2)

				{

				if (ctx->tmp[jj-1] == '=')

					{

					z--;

					if (ctx->tmp[jj-2] == '=')

						z--;

					}

				}

			/* z is now number of output bytes and jj is the

			 * number consumed */

			if (jj != i)

				{

				memcpy((unsigned char *)ctx->tmp,

					(unsigned char *)&(ctx->tmp[jj]),i-jj);

				ctx->tmp_len=i-jj;

				}

			ctx->buf_len=0;

			if (z > 0)

				{

				ctx->buf_len=z;

				i=1;

				}

			else

				i=z;

			}

		else

			{

			i=EVP_DecodeUpdate(&(ctx->base64),

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

				(unsigned char *)ctx->tmp,i);

			ctx->tmp_len = 0;

			}

		ctx->buf_off=0;

		if (i < 0)

			{

			ret_code=0;

			ctx->buf_len=0;

			break;

			}

		if (ctx->buf_len <= outl)

			i=ctx->buf_len;

		else

			i=outl;

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

		ret+=i;

		ctx->buf_off=i;

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

			{

			ctx->buf_len=0;

			ctx->buf_off=0;

			}

		outl-=i;

		out+=i;

		}

	BIO_clear_retry_flags(b);

	BIO_copy_next_retry(b);

	return((ret == 0)?ret_code:ret);

	}

static int b64_write(BIO *b, const char *in, int inl)

	{

	int ret=inl,n,i;

	BIO_B64_CTX *ctx;

	ctx=(BIO_B64_CTX *)b->ptr;

	BIO_clear_retry_flags(b);

	if (ctx->encode != B64_ENCODE)

		{

		ctx->encode=B64_ENCODE;

		ctx->buf_len=0;

		ctx->buf_off=0;

		ctx->tmp_len=0;

		EVP_EncodeInit(&(ctx->base64));

		}

	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 */

	ctx->buf_off=0;

	ctx->buf_len=0;

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

	while (inl > 0)

		{

		n=(inl > B64_BLOCK_SIZE)?B64_BLOCK_SIZE:inl;

		if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)

			{

			if (ctx->tmp_len > 0)

				{

				n=3-ctx->tmp_len;

				/* There's a teoretical possibility for this */

				if (n > inl) 

					n=inl;

				memcpy(&(ctx->tmp[ctx->tmp_len]),in,n);

				ctx->tmp_len+=n;

				if (ctx->tmp_len < 3)

					break;

				ctx->buf_len=EVP_EncodeBlock(

					(unsigned char *)ctx->buf,

					(unsigned char *)ctx->tmp,

					ctx->tmp_len);

				/* Since we're now done using the temporary

				   buffer, the length should be 0'd */

				ctx->tmp_len=0;

				}

			else

				{

				if (n < 3)

					{

					memcpy(&(ctx->tmp[0]),in,n);

					ctx->tmp_len=n;

					break;

					}

				n-=n%3;

				ctx->buf_len=EVP_EncodeBlock(

					(unsigned char *)ctx->buf,

					(unsigned char *)in,n);

				}

			}

		else

			{

			EVP_EncodeUpdate(&(ctx->base64),

				(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 == 0)?i:ret);

				}

			n-=i;

			ctx->buf_off+=i;

			}

		ctx->buf_len=0;

		ctx->buf_off=0;

		}

	return(ret);

	}

static long b64_ctrl(BIO *b, int cmd, long num, void *ptr)

	{

	BIO_B64_CTX *ctx;

	long ret=1;

	int i;

	ctx=(BIO_B64_CTX *)b->ptr;

	switch (cmd)

		{

	case BIO_CTRL_RESET:

		ctx->cont=1;

		ctx->start=1;

		ctx->encode=B64_NONE;

		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: /* More to write in buffer */

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

		if ((ret == 0) && (ctx->encode != B64_NONE)

			&& (ctx->base64.num != 0))

			ret=1;

		else 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=b64_write(b,NULL,0);

			if (i < 0)

				return i;

			}

		if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)

			{

			if (ctx->tmp_len != 0)

				{

				ctx->buf_len=EVP_EncodeBlock(

					(unsigned char *)ctx->buf,

					(unsigned char *)ctx->tmp,

					ctx->tmp_len);

				ctx->buf_off=0;

				ctx->tmp_len=0;

				goto again;

				}

			}

		else if (ctx->encode != B64_NONE && ctx->base64.num != 0)

			{

			ctx->buf_off=0;

			EVP_EncodeFinal(&(ctx->base64),

				(unsigned char *)ctx->buf,

				&(ctx->buf_len));

			/* push out the bytes */

			goto again;

			}

		/* Finally flush the underlying BIO */

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

		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_CTRL_DUP:

		break;

	case BIO_CTRL_INFO:

	case BIO_CTRL_GET:

	case BIO_CTRL_SET:

	default:

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

		break;

		}

	return(ret);

	}

static long b64_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);

	}