winamp/Src/auth/b64.c

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/* /////////////////////////////////////////////////////////////////////////////
* File: b64.c
*
* Purpose: Implementation file for the b64 library
*
* Created: 18th October 2004
* Updated: 9th February 2008
*
* Home: http://synesis.com.au/software/
*
* Copyright (c) 2004-2008, Matthew Wilson and Synesis Software
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* - 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.
* - Neither the name(s) of Matthew Wilson and Synesis Software nor the names of
* any contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER 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.
*
* ////////////////////////////////////////////////////////////////////////// */
/** \file b64.c Implementation file for the b64 library
*/
/* /////////////////////////////////////////////////////////////////////////////
* Version information
*/
#ifndef B64_DOCUMENTATION_SKIP_SECTION
# define B64_VER_C_B64_MAJOR 1
# define B64_VER_C_B64_MINOR 2
# define B64_VER_C_B64_REVISION 2
# define B64_VER_C_B64_EDIT 16
#endif /* !B64_DOCUMENTATION_SKIP_SECTION */
/* /////////////////////////////////////////////////////////////////////////////
* Includes
*/
#include "b64.h"
#include <assert.h>
#include <string.h>
/* /////////////////////////////////////////////////////////////////////////////
* Constants and definitions
*/
#ifndef B64_DOCUMENTATION_SKIP_SECTION
# define NUM_PLAIN_DATA_BYTES (3)
# define NUM_ENCODED_DATA_BYTES (4)
#endif /* !B64_DOCUMENTATION_SKIP_SECTION */
/* /////////////////////////////////////////////////////////////////////////////
* Macros
*/
#ifndef NUM_ELEMENTS
# define NUM_ELEMENTS(x) (sizeof(x) / sizeof(x[0]))
#endif /* !NUM_ELEMENTS */
/* /////////////////////////////////////////////////////////////////////////////
* Warnings
*/
#if defined(_MSC_VER) && \
_MSC_VER < 1000
# pragma warning(disable : 4705)
#endif /* _MSC_VER < 1000 */
/* /////////////////////////////////////////////////////////////////////////////
* Data
*/
static const char b64_chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const signed char b64_indexes[] =
{
/* 0 - 31 / 0x00 - 0x1f */
-1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
/* 32 - 63 / 0x20 - 0x3f */
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, 62, -1, -1, -1, 63 /* ... , '+', ... '/' */
, 52, 53, 54, 55, 56, 57, 58, 59 /* '0' - '7' */
, 60, 61, -1, -1, -1, -1, -1, -1 /* '8', '9', ... */
/* 64 - 95 / 0x40 - 0x5f */
, -1, 0, 1, 2, 3, 4, 5, 6 /* ..., 'A' - 'G' */
, 7, 8, 9, 10, 11, 12, 13, 14 /* 'H' - 'O' */
, 15, 16, 17, 18, 19, 20, 21, 22 /* 'P' - 'W' */
, 23, 24, 25, -1, -1, -1, -1, -1 /* 'X', 'Y', 'Z', ... */
/* 96 - 127 / 0x60 - 0x7f */
, -1, 26, 27, 28, 29, 30, 31, 32 /* ..., 'a' - 'g' */
, 33, 34, 35, 36, 37, 38, 39, 40 /* 'h' - 'o' */
, 41, 42, 43, 44, 45, 46, 47, 48 /* 'p' - 'w' */
, 49, 50, 51, -1, -1, -1, -1, -1 /* 'x', 'y', 'z', ... */
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
, -1, -1, -1, -1, -1, -1, -1, -1
};
/* /////////////////////////////////////////////////////////////////////////////
* Helper functions
*/
/** This function reads in 3 bytes at a time, and translates them into 4
* characters.
*/
static size_t b64_encode_( unsigned char const *src
, size_t srcSize
, char *const dest
, size_t destLen
, unsigned lineLen
, B64_RC *rc)
{
size_t total = ((srcSize + (NUM_PLAIN_DATA_BYTES - 1)) / NUM_PLAIN_DATA_BYTES) * NUM_ENCODED_DATA_BYTES;
assert(NULL != rc);
*rc = B64_RC_OK;
if(lineLen > 0)
{
unsigned numLines = (unsigned int)(total + (lineLen - 1)) / lineLen;
total += 2 * (numLines - 1);
}
if(NULL == dest)
{
return total;
}
else if(destLen < total)
{
*rc = B64_RC_INSUFFICIENT_BUFFER;
return 0;
}
else
{
char *p = dest;
char *end = dest + destLen;
size_t len = 0;
for(; NUM_PLAIN_DATA_BYTES <= srcSize; srcSize -= NUM_PLAIN_DATA_BYTES)
{
char characters[NUM_ENCODED_DATA_BYTES] = {0};
/*
*
* | 0 | 1 | 2 |
*
* | | | |
* | | | | | | |
* | | | | | | | | | | | | |
* | | | | | | | | | | | | | | | | | | | | | | | | |
*
* | 0 | 1 | 2 | 3 |
*
*/
/* characters[0] is the 6 left-most bits of src[0] */
characters[0] = (char)((src[0] & 0xfc) >> 2);
/* characters[0] is the right-most 2 bits of src[0] and the left-most 4 bits of src[1] */
characters[1] = (char)(((src[0] & 0x03) << 4) + ((src[1] & 0xf0) >> 4));
/* characters[0] is the right-most 4 bits of src[1] and the 2 left-most bits of src[2] */
characters[2] = (char)(((src[1] & 0x0f) << 2) + ((src[2] & 0xc0) >> 6));
/* characters[3] is the right-most 6 bits of src[2] */
characters[3] = (char)(src[2] & 0x3f);
#ifndef __WATCOMC__
assert(characters[0] >= 0 && characters[0] < 64);
assert(characters[1] >= 0 && characters[1] < 64);
assert(characters[2] >= 0 && characters[2] < 64);
assert(characters[3] >= 0 && characters[3] < 64);
#endif /* __WATCOMC__ */
src += NUM_PLAIN_DATA_BYTES;
*p++ = b64_chars[(unsigned char)characters[0]];
assert(NULL != strchr(b64_chars, *(p-1)));
++len;
assert(len != lineLen);
*p++ = b64_chars[(unsigned char)characters[1]];
assert(NULL != strchr(b64_chars, *(p-1)));
++len;
assert(len != lineLen);
*p++ = b64_chars[(unsigned char)characters[2]];
assert(NULL != strchr(b64_chars, *(p-1)));
++len;
assert(len != lineLen);
*p++ = b64_chars[(unsigned char)characters[3]];
assert(NULL != strchr(b64_chars, *(p-1)));
if( ++len == lineLen &&
p != end)
{
*p++ = '\r';
*p++ = '\n';
len = 0;
}
}
if(0 != srcSize)
{
/* Deal with the overspill, by boosting it up to three bytes (using 0s)
* and then appending '=' for any missing characters.
*
* This is done into a temporary buffer, so we can call ourselves and
* have the output continue to be written direct to the destination.
*/
unsigned char dummy[NUM_PLAIN_DATA_BYTES] = {0};
size_t i;
for(i = 0; i < srcSize; ++i)
{
dummy[i] = *src++;
}
for(; i < NUM_PLAIN_DATA_BYTES; ++i)
{
dummy[i] = '\0';
}
b64_encode_(&dummy[0], NUM_PLAIN_DATA_BYTES, p, NUM_ENCODED_DATA_BYTES * (1 + 2), 0, rc);
for(p += 1 + srcSize; srcSize++ < NUM_PLAIN_DATA_BYTES; )
{
*p++ = '=';
}
}
return total;
}
}
/** This function reads in a character string in 4-character chunks, and writes
* out the converted form in 3-byte chunks to the destination.
*/
static size_t b64_decode_( char const *src
, size_t srcLen
, unsigned char *dest
, size_t destSize
, unsigned flags
, char const **badChar
, B64_RC *rc)
{
const size_t wholeChunks = (srcLen / NUM_ENCODED_DATA_BYTES);
const size_t remainderBytes = (srcLen % NUM_ENCODED_DATA_BYTES);
size_t maxTotal = (wholeChunks + (0 != remainderBytes)) * NUM_PLAIN_DATA_BYTES;
unsigned char *dest_ = dest;
((void)remainderBytes);
assert(NULL != badChar);
assert(NULL != rc);
*badChar = NULL;
*rc = B64_RC_OK;
if(NULL == dest)
{
return maxTotal;
}
else if(destSize < maxTotal)
{
*rc = B64_RC_INSUFFICIENT_BUFFER;
return 0;
}
else
{
/* Now we iterate through the src, collecting together four characters
* at a time from the Base-64 alphabet, until the end-point is reached.
*
*
*/
char const *begin = src;
char const *const end = begin + srcLen;
size_t currIndex = 0;
size_t numPads = 0;
signed char indexes[NUM_ENCODED_DATA_BYTES] = {0}; /* 4 */
for(; begin != end; ++begin)
{
const char ch = *begin;
if('=' == ch)
{
assert(currIndex < NUM_ENCODED_DATA_BYTES);
indexes[currIndex++] = '\0';
++numPads;
}
else
{
/* NOTE: Had to rename 'index' to 'ix', due to name clash with GCC on 64-bit Linux. */
signed char ix = b64_indexes[(unsigned char)ch];
if(-1 == ix)
{
switch(ch)
{
case ' ':
case '\t':
case '\b':
case '\v':
if(B64_F_STOP_ON_UNEXPECTED_WS & flags)
{
*rc = B64_RC_DATA_ERROR;
*badChar = begin;
return 0;
}
else
{
/* Fall through */
}
case '\r':
case '\n':
continue;
default:
if(B64_F_STOP_ON_UNKNOWN_CHAR & flags)
{
*rc = B64_RC_DATA_ERROR;
*badChar = begin;
return 0;
}
else
{
continue;
}
}
}
else
{
numPads = 0;
assert(currIndex < NUM_ENCODED_DATA_BYTES);
indexes[currIndex++] = ix;
}
}
if(NUM_ENCODED_DATA_BYTES == currIndex)
{
unsigned char bytes[NUM_PLAIN_DATA_BYTES] = {0}; /* 3 */
bytes[0] = (unsigned char)((indexes[0] << 2) + ((indexes[1] & 0x30) >> 4));
currIndex = 0;
*dest++ = bytes[0];
if(2 != numPads)
{
bytes[1] = (unsigned char)(((indexes[1] & 0xf) << 4) + ((indexes[2] & 0x3c) >> 2));
*dest++ = bytes[1];
if(1 != numPads)
{
bytes[2] = (unsigned char)(((indexes[2] & 0x3) << 6) + indexes[3]);
*dest++ = bytes[2];
}
}
if(0 != numPads)
{
break;
}
}
}
return (size_t)(dest - dest_);
}
}
/* /////////////////////////////////////////////////////////////////////////////
* API functions
*/
size_t b64_encode(void const *src, size_t srcSize, char *dest, size_t destLen)
{
/* Use Null Object (Variable) here for rc, so do not need to check
* elsewhere.
*/
B64_RC rc_;
return b64_encode_((unsigned char const*)src, srcSize, dest, destLen, 0, &rc_);
}
size_t b64_encode2( void const *src
, size_t srcSize
, char *dest
, size_t destLen
, unsigned flags
, int lineLen /* = -1 */
, B64_RC *rc /* = NULL */)
{
/* Use Null Object (Variable) here for rc, so do not need to check
* elsewhere
*/
B64_RC rc_;
if(NULL == rc)
{
rc = &rc_;
}
switch(B64_F_LINE_LEN_MASK & flags)
{
case B64_F_LINE_LEN_USE_PARAM:
if(lineLen >= 0)
{
break;
}
/* Fall through to 64 */
case B64_F_LINE_LEN_64:
lineLen = 64;
break;
case B64_F_LINE_LEN_76:
lineLen = 76;
break;
default:
assert(!"Bad line length flag specified to b64_encode2()");
case B64_F_LINE_LEN_INFINITE:
lineLen = 0;
break;
}
assert(0 == (lineLen % 4));
return b64_encode_((unsigned char const*)src, srcSize, dest, destLen, (unsigned)lineLen, rc);
}
size_t b64_decode(char const *src, size_t srcLen, void *dest, size_t destSize)
{
/* Use Null Object (Variable) here for rc and badChar, so do not need to
* check elsewhere.
*/
char const *badChar_;
B64_RC rc_;
return b64_decode_(src, srcLen, (unsigned char*)dest, destSize, B64_F_STOP_ON_NOTHING, &badChar_, &rc_);
}
size_t b64_decode2( char const *src
, size_t srcLen
, void *dest
, size_t destSize
, unsigned flags
, char const **badChar /* = NULL */
, B64_RC *rc /* = NULL */)
{
char const *badChar_;
B64_RC rc_;
/* Use Null Object (Variable) here for rc and badChar, so do not need to
* check elsewhere.
*/
if(NULL == badChar)
{
badChar = &badChar_;
}
if(NULL == rc)
{
rc = &rc_;
}
return b64_decode_(src, srcLen, (unsigned char*)dest, destSize, flags, badChar, rc);
}
/* ////////////////////////////////////////////////////////////////////////// */
#ifdef B64_DOCUMENTATION_SKIP_SECTION
struct b64ErrorString_t_
#else /* !B64_DOCUMENTATION_SKIP_SECTION */
typedef struct b64ErrorString_t_ b64ErrorString_t_;
struct b64ErrorString_t_
#endif /* !B64_DOCUMENTATION_SKIP_SECTION */
{
int code; /*!< The error code. */
char const *str; /*!< The string. */
size_t len; /*!< The string length. */
};
#define SEVERITY_STR_DECL(rc, desc) \
\
static const char s_str##rc[] = desc; \
static const b64ErrorString_t_ s_rct##rc = { rc, s_str##rc, NUM_ELEMENTS(s_str##rc) - 1 }
#define SEVERITY_STR_ENTRY(rc) \
\
&s_rct##rc
static char const *b64_LookupCodeA_(int code, b64ErrorString_t_ const **mappings, size_t cMappings, size_t *len)
{
/* Use Null Object (Variable) here for len, so do not need to check
* elsewhere.
*/
size_t len_;
if(NULL == len)
{
len = &len_;
}
/* Checked, indexed search. */
if( code >= 0 &&
code < B64_max_RC_value)
{
if(code == mappings[code]->code)
{
return (*len = mappings[code]->len, mappings[code]->str);
}
}
/* Linear search. Should only be needed if order in
* b64_LookupErrorStringA_() messed up.
*/
{ size_t i; for(i = 0; i < cMappings; ++i)
{
if(code == mappings[i]->code)
{
return (*len = mappings[i]->len, mappings[i]->str);
}
}}
return (*len = 0, "");
}
static char const *b64_LookupErrorStringA_(int error, size_t *len)
{
SEVERITY_STR_DECL(B64_RC_OK , "Operation was successful" );
SEVERITY_STR_DECL(B64_RC_INSUFFICIENT_BUFFER , "The given translation buffer was not of sufficient size" );
SEVERITY_STR_DECL(B64_RC_TRUNCATED_INPUT , "The input did not represent a fully formed stream of octet couplings" );
SEVERITY_STR_DECL(B64_RC_DATA_ERROR , "Invalid data" );
static const b64ErrorString_t_ *s_strings[] =
{
SEVERITY_STR_ENTRY(B64_RC_OK),
SEVERITY_STR_ENTRY(B64_RC_INSUFFICIENT_BUFFER),
SEVERITY_STR_ENTRY(B64_RC_TRUNCATED_INPUT),
SEVERITY_STR_ENTRY(B64_RC_DATA_ERROR),
};
return b64_LookupCodeA_(error, s_strings, NUM_ELEMENTS(s_strings), len);
}
char const *b64_getErrorString(B64_RC code)
{
return b64_LookupErrorStringA_((int)code, NULL);
}
size_t b64_getErrorStringLength(B64_RC code)
{
size_t len;
return (b64_LookupErrorStringA_((int)code, &len), len);
}
/* ////////////////////////////////////////////////////////////////////////// */