clean up the decode mess somewhat

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@10012 ec53bebd-3082-4978-b11e-865c3cabbd6b
This commit is contained in:
Johan Danielsson
2001-05-28 17:33:41 +00:00
parent 90cb53e2c1
commit cb3a6310d4

View File

@@ -1,5 +1,5 @@
/*
* Copyright (c) 1995 - 1999 Kungliga Tekniska H<>gskolan
* Copyright (c) 1995-2001 Kungliga Tekniska H<>gskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
@@ -39,18 +39,21 @@ RCSID("$Id$");
#include <string.h>
#include "base64.h"
static char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static char base64_chars[] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static int pos(char c)
static int
pos(char c)
{
char *p;
for(p = base64; *p; p++)
for (p = base64_chars; *p; p++)
if (*p == c)
return p - base64;
return p - base64_chars;
return -1;
}
int base64_encode(const void *data, int size, char **str)
int
base64_encode(const void *data, int size, char **str)
{
char *s, *p;
int i;
@@ -72,10 +75,10 @@ int base64_encode(const void *data, int size, char **str)
if (i < size)
c += q[i];
i++;
p[0]=base64[(c&0x00fc0000) >> 18];
p[1]=base64[(c&0x0003f000) >> 12];
p[2]=base64[(c&0x00000fc0) >> 6];
p[3]=base64[(c&0x0000003f) >> 0];
p[0] = base64_chars[(c & 0x00fc0000) >> 18];
p[1] = base64_chars[(c & 0x0003f000) >> 12];
p[2] = base64_chars[(c & 0x00000fc0) >> 6];
p[3] = base64_chars[(c & 0x0000003f) >> 0];
if (i > size)
p[3] = '=';
if (i > size + 1)
@@ -87,60 +90,47 @@ int base64_encode(const void *data, int size, char **str)
return strlen(s);
}
int base64_decode(const char *str, void *data)
#define DECODE_ERROR 0xffffffff
static unsigned int
token_decode(const char *token)
{
int i;
unsigned int val = 0;
int marker = 0;
if (strlen(token) < 4)
return DECODE_ERROR;
for (i = 0; i < 4; i++) {
val *= 64;
if (token[i] == '=')
marker++;
else if (marker > 0)
return DECODE_ERROR;
else
val += pos(token[i]);
}
if (marker > 2)
return DECODE_ERROR;
return (marker << 24) | val;
}
int
base64_decode(const char *str, void *data)
{
const char *p;
unsigned char *q;
int c;
int x;
int done = 0;
q=(unsigned char*)data;
for(p=str; *p && !done; p+=4){
x = pos(p[0]);
if(x >= 0)
c = x;
else{
done = 3;
break;
}
c*=64;
x = pos(p[1]);
if(x >= 0)
c += x;
else
q = data;
for (p = str; *p && (*p == '=' || strchr(base64_chars, *p)); p += 4) {
unsigned int val = token_decode(p);
unsigned int marker = (val >> 24) & 0xff;
if (val == DECODE_ERROR)
return -1;
c*=64;
if(p[2] == '=')
done++;
else{
x = pos(p[2]);
if(x >= 0)
c += x;
else
return -1;
}
c*=64;
if(p[3] == '=')
done++;
else{
if(done)
return -1;
x = pos(p[3]);
if(x >= 0)
c += x;
else
return -1;
}
if(done < 3)
*q++=(c&0x00ff0000)>>16;
if(done < 2)
*q++=(c&0x0000ff00)>>8;
if(done < 1)
*q++=(c&0x000000ff)>>0;
*q++ = (val >> 16) & 0xff;
if (marker < 2)
*q++ = (val >> 8) & 0xff;
if (marker < 1)
*q++ = val & 0xff;
}
return q - (unsigned char *) data;
}