crypto/evp/bio_b64.c - platform/external/openssl - Git at Google

 /* 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.]
  */

 #include <stdio.h>
 #include <errno.h>
 #include "cryptlib.h"
 #include <openssl/buffer.h>
 #include <openssl/evp.h>

 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;

 static BIO_METHOD methods_b64=
 	{
 	BIO_TYPE_BASE64,"base64 encoding",
 	b64_write,
 	b64_read,
 	b64_puts,
 	NULL, /* b64_gets, */
 	b64_ctrl,
 	b64_new,
 	b64_free,
 	b64_callback_ctrl,
 	};

 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;
 	bi->num = 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);

 	BIO_clear_retry_flags(b);

 	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)
 		{
 		OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 		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 we 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;
 			}
 		}
 		else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0))
 		{
 			/* If buffer isn't full and we can retry then
 			 * restart to read in more data.
 			 */
 			continue;
 		}

 		if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
 			{
 			int z,jj;

 #if 0
 			jj=(i>>2)<<2;
 #else
 			jj = i & ~3; /* process per 4 */
 #endif
 			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)
 				{
 				memmove(ctx->tmp, &ctx->tmp[jj], i-jj);
 				ctx->tmp_len=i-jj;
 				}
 			ctx->buf_len=0;
 			if (z > 0)
 				{
 				ctx->buf_len=z;
 				}
 			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=0;
 	int n;
 	int 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));
 		}

 	OPENSSL_assert(ctx->buf_off < (int)sizeof(ctx->buf));
 	OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
 	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 	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);
 			}
 		OPENSSL_assert(i <= n);
 		ctx->buf_off+=i;
 		OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
 		OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 		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)
 				{
 				OPENSSL_assert(ctx->tmp_len <= 3);
 				n=3-ctx->tmp_len;
 				/* There's a theoretical possibility for this */
 				if (n > inl)
 					n=inl;
 				memcpy(&(ctx->tmp[ctx->tmp_len]),in,n);
 				ctx->tmp_len+=n;
 				ret += n;
 				if (ctx->tmp_len < 3)
 					break;
 				ctx->buf_len=EVP_EncodeBlock((unsigned char *)ctx->buf,(unsigned char *)ctx->tmp,ctx->tmp_len);
 				OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
 				OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 				/* 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,in,n);
 					ctx->tmp_len=n;
 					ret += n;
 					break;
 					}
 				n-=n%3;
 				ctx->buf_len=EVP_EncodeBlock((unsigned char *)ctx->buf,(const unsigned char *)in,n);
 				OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
 				OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 				ret += n;
 				}
 			}
 		else
 			{
 			EVP_EncodeUpdate(&(ctx->base64),
 				(unsigned char *)ctx->buf,&ctx->buf_len,
 				(unsigned char *)in,n);
 			OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
 			OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 			ret += 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);
 				}
 			OPENSSL_assert(i <= n);
 			n-=i;
 			ctx->buf_off+=i;
 			OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
 			OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 			}
 		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 */
 		OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 		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 */
 		OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
 		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);
 	}

 static int b64_puts(BIO *b, const char *str)
 	{
 	return b64_write(b,str,strlen(str));
 	}
	/* 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.]
	*/

	#include <stdio.h>
	#include <errno.h>
	#include "cryptlib.h"
	#include <openssl/buffer.h>
	#include <openssl/evp.h>

	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;

	static BIO_METHOD methods_b64=
	{
	BIO_TYPE_BASE64,"base64 encoding",
	b64_write,
	b64_read,
	b64_puts,
	NULL, /* b64_gets, */
	b64_ctrl,
	b64_new,
	b64_free,
	b64_callback_ctrl,
	};

	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;
	bi->num = 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);

	BIO_clear_retry_flags(b);

	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)
	{
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	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 we 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;
	}
	}
	else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0))
	{
	/* If buffer isn't full and we can retry then
	* restart to read in more data.
	*/
	continue;
	}

	if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
	{
	int z,jj;

	#if 0
	jj=(i>>2)<<2;
	#else
	jj = i & ~3; /* process per 4 */
	#endif
	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)
	{
	memmove(ctx->tmp, &ctx->tmp[jj], i-jj);
	ctx->tmp_len=i-jj;
	}
	ctx->buf_len=0;
	if (z > 0)
	{
	ctx->buf_len=z;
	}
	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=0;
	int n;
	int 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));
	}

	OPENSSL_assert(ctx->buf_off < (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	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);
	}
	OPENSSL_assert(i <= n);
	ctx->buf_off+=i;
	OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	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)
	{
	OPENSSL_assert(ctx->tmp_len <= 3);
	n=3-ctx->tmp_len;
	/* There's a theoretical possibility for this */
	if (n > inl)
	n=inl;
	memcpy(&(ctx->tmp[ctx->tmp_len]),in,n);
	ctx->tmp_len+=n;
	ret += n;
	if (ctx->tmp_len < 3)
	break;
	ctx->buf_len=EVP_EncodeBlock((unsigned char )ctx->buf,(unsigned char )ctx->tmp,ctx->tmp_len);
	OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	/* 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,in,n);
	ctx->tmp_len=n;
	ret += n;
	break;
	}
	n-=n%3;
	ctx->buf_len=EVP_EncodeBlock((unsigned char )ctx->buf,(const unsigned char )in,n);
	OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	ret += n;
	}
	}
	else
	{
	EVP_EncodeUpdate(&(ctx->base64),
	(unsigned char *)ctx->buf,&ctx->buf_len,
	(unsigned char *)in,n);
	OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	ret += 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);
	}
	OPENSSL_assert(i <= n);
	n-=i;
	ctx->buf_off+=i;
	OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	}
	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 */
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	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 */
	OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
	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);
	}

	static int b64_puts(BIO b, const char str)
	{
	return b64_write(b,str,strlen(str));
	}