diff options
Diffstat (limited to 'mozilla/nsprpub/lib/libc/src/base64.c')
-rw-r--r-- | mozilla/nsprpub/lib/libc/src/base64.c | 448 |
1 files changed, 448 insertions, 0 deletions
diff --git a/mozilla/nsprpub/lib/libc/src/base64.c b/mozilla/nsprpub/lib/libc/src/base64.c new file mode 100644 index 0000000..e3fd80d --- /dev/null +++ b/mozilla/nsprpub/lib/libc/src/base64.c @@ -0,0 +1,448 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* ***** BEGIN LICENSE BLOCK ***** + * Version: MPL 1.1/GPL 2.0/LGPL 2.1 + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + * + * The Original Code is the Netscape Portable Runtime (NSPR). + * + * The Initial Developer of the Original Code is + * Netscape Communications Corporation. + * Portions created by the Initial Developer are Copyright (C) 1998-2000 + * the Initial Developer. All Rights Reserved. + * + * Contributor(s): + * + * Alternatively, the contents of this file may be used under the terms of + * either the GNU General Public License Version 2 or later (the "GPL"), or + * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), + * in which case the provisions of the GPL or the LGPL are applicable instead + * of those above. If you wish to allow use of your version of this file only + * under the terms of either the GPL or the LGPL, and not to allow others to + * use your version of this file under the terms of the MPL, indicate your + * decision by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL or the LGPL. If you do not delete + * the provisions above, a recipient may use your version of this file under + * the terms of any one of the MPL, the GPL or the LGPL. + * + * ***** END LICENSE BLOCK ***** */ + +#include "plbase64.h" +#include "prlog.h" /* For PR_NOT_REACHED */ +#include "prmem.h" /* for malloc / PR_MALLOC */ + +#include <string.h> /* for strlen */ + +static unsigned char *base = (unsigned char *)"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +static void +encode3to4 +( + const unsigned char *src, + unsigned char *dest +) +{ + PRUint32 b32 = (PRUint32)0; + PRIntn i, j = 18; + + for( i = 0; i < 3; i++ ) + { + b32 <<= 8; + b32 |= (PRUint32)src[i]; + } + + for( i = 0; i < 4; i++ ) + { + dest[i] = base[ (PRUint32)((b32>>j) & 0x3F) ]; + j -= 6; + } + + return; +} + +static void +encode2to4 +( + const unsigned char *src, + unsigned char *dest +) +{ + dest[0] = base[ (PRUint32)((src[0]>>2) & 0x3F) ]; + dest[1] = base[ (PRUint32)(((src[0] & 0x03) << 4) | ((src[1] >> 4) & 0x0F)) ]; + dest[2] = base[ (PRUint32)((src[1] & 0x0F) << 2) ]; + dest[3] = (unsigned char)'='; + return; +} + +static void +encode1to4 +( + const unsigned char *src, + unsigned char *dest +) +{ + dest[0] = base[ (PRUint32)((src[0]>>2) & 0x3F) ]; + dest[1] = base[ (PRUint32)((src[0] & 0x03) << 4) ]; + dest[2] = (unsigned char)'='; + dest[3] = (unsigned char)'='; + return; +} + +static void +encode +( + const unsigned char *src, + PRUint32 srclen, + unsigned char *dest +) +{ + while( srclen >= 3 ) + { + encode3to4(src, dest); + src += 3; + dest += 4; + srclen -= 3; + } + + switch( srclen ) + { + case 2: + encode2to4(src, dest); + break; + case 1: + encode1to4(src, dest); + break; + case 0: + break; + default: + PR_NOT_REACHED("coding error"); + } + + return; +} + +/* + * PL_Base64Encode + * + * If the destination argument is NULL, a return buffer is + * allocated, and the data therein will be null-terminated. + * If the destination argument is not NULL, it is assumed to + * be of sufficient size, and the contents will not be null- + * terminated by this routine. + * + * Returns null if the allocation fails. + */ + +PR_IMPLEMENT(char *) +PL_Base64Encode +( + const char *src, + PRUint32 srclen, + char *dest +) +{ + if( 0 == srclen ) + { + size_t len = strlen(src); + srclen = len; + /* Detect truncation. */ + if( srclen != len ) + { + return (char *)0; + } + } + + if( (char *)0 == dest ) + { + PRUint32 destlen; + /* Ensure all PRUint32 values stay within range. */ + if( srclen > (PR_UINT32_MAX/4) * 3 ) + { + return (char *)0; + } + destlen = ((srclen + 2)/3) * 4; + dest = (char *)PR_MALLOC(destlen + 1); + if( (char *)0 == dest ) + { + return (char *)0; + } + dest[ destlen ] = (char)0; /* null terminate */ + } + + encode((const unsigned char *)src, srclen, (unsigned char *)dest); + return dest; +} + +static PRInt32 +codetovalue +( + unsigned char c +) +{ + if( (c >= (unsigned char)'A') && (c <= (unsigned char)'Z') ) + { + return (PRInt32)(c - (unsigned char)'A'); + } + else if( (c >= (unsigned char)'a') && (c <= (unsigned char)'z') ) + { + return ((PRInt32)(c - (unsigned char)'a') +26); + } + else if( (c >= (unsigned char)'0') && (c <= (unsigned char)'9') ) + { + return ((PRInt32)(c - (unsigned char)'0') +52); + } + else if( (unsigned char)'+' == c ) + { + return (PRInt32)62; + } + else if( (unsigned char)'/' == c ) + { + return (PRInt32)63; + } + else + { + return -1; + } +} + +static PRStatus +decode4to3 +( + const unsigned char *src, + unsigned char *dest +) +{ + PRUint32 b32 = (PRUint32)0; + PRInt32 bits; + PRIntn i; + + for( i = 0; i < 4; i++ ) + { + bits = codetovalue(src[i]); + if( bits < 0 ) + { + return PR_FAILURE; + } + + b32 <<= 6; + b32 |= bits; + } + + dest[0] = (unsigned char)((b32 >> 16) & 0xFF); + dest[1] = (unsigned char)((b32 >> 8) & 0xFF); + dest[2] = (unsigned char)((b32 ) & 0xFF); + + return PR_SUCCESS; +} + +static PRStatus +decode3to2 +( + const unsigned char *src, + unsigned char *dest +) +{ + PRUint32 b32 = (PRUint32)0; + PRInt32 bits; + PRUint32 ubits; + + bits = codetovalue(src[0]); + if( bits < 0 ) + { + return PR_FAILURE; + } + + b32 = (PRUint32)bits; + b32 <<= 6; + + bits = codetovalue(src[1]); + if( bits < 0 ) + { + return PR_FAILURE; + } + + b32 |= (PRUint32)bits; + b32 <<= 4; + + bits = codetovalue(src[2]); + if( bits < 0 ) + { + return PR_FAILURE; + } + + ubits = (PRUint32)bits; + b32 |= (ubits >> 2); + + dest[0] = (unsigned char)((b32 >> 8) & 0xFF); + dest[1] = (unsigned char)((b32 ) & 0xFF); + + return PR_SUCCESS; +} + +static PRStatus +decode2to1 +( + const unsigned char *src, + unsigned char *dest +) +{ + PRUint32 b32; + PRUint32 ubits; + PRInt32 bits; + + bits = codetovalue(src[0]); + if( bits < 0 ) + { + return PR_FAILURE; + } + + ubits = (PRUint32)bits; + b32 = (ubits << 2); + + bits = codetovalue(src[1]); + if( bits < 0 ) + { + return PR_FAILURE; + } + + ubits = (PRUint32)bits; + b32 |= (ubits >> 4); + + dest[0] = (unsigned char)b32; + + return PR_SUCCESS; +} + +static PRStatus +decode +( + const unsigned char *src, + PRUint32 srclen, + unsigned char *dest +) +{ + PRStatus rv; + + while( srclen >= 4 ) + { + rv = decode4to3(src, dest); + if( PR_SUCCESS != rv ) + { + return PR_FAILURE; + } + + src += 4; + dest += 3; + srclen -= 4; + } + + switch( srclen ) + { + case 3: + rv = decode3to2(src, dest); + break; + case 2: + rv = decode2to1(src, dest); + break; + case 1: + rv = PR_FAILURE; + break; + case 0: + rv = PR_SUCCESS; + break; + default: + PR_NOT_REACHED("coding error"); + } + + return rv; +} + +/* + * PL_Base64Decode + * + * If the destination argument is NULL, a return buffer is + * allocated and the data therein will be null-terminated. + * If the destination argument is not null, it is assumed + * to be of sufficient size, and the data will not be null- + * terminated by this routine. + * + * Returns null if the allocation fails, or if the source string is + * not well-formed. + */ + +PR_IMPLEMENT(char *) +PL_Base64Decode +( + const char *src, + PRUint32 srclen, + char *dest +) +{ + PRStatus status; + PRBool allocated = PR_FALSE; + + if( (char *)0 == src ) + { + return (char *)0; + } + + if( 0 == srclen ) + { + size_t len = strlen(src); + srclen = len; + /* Detect truncation. */ + if( srclen != len ) + { + return (char *)0; + } + } + + if( srclen && (0 == (srclen & 3)) ) + { + if( (char)'=' == src[ srclen-1 ] ) + { + if( (char)'=' == src[ srclen-2 ] ) + { + srclen -= 2; + } + else + { + srclen -= 1; + } + } + } + + if( (char *)0 == dest ) + { + /* The following computes ((srclen * 3) / 4) without overflow. */ + PRUint32 destlen = (srclen / 4) * 3 + ((srclen % 4) * 3) / 4; + dest = (char *)PR_MALLOC(destlen + 1); + if( (char *)0 == dest ) + { + return (char *)0; + } + dest[ destlen ] = (char)0; /* null terminate */ + allocated = PR_TRUE; + } + + status = decode((const unsigned char *)src, srclen, (unsigned char *)dest); + if( PR_SUCCESS != status ) + { + if( PR_TRUE == allocated ) + { + PR_DELETE(dest); + } + + return (char *)0; + } + + return dest; +} |