/* 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,
NULL, /* 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;
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);
}