The Tor Browser: comparison nsprpub/lib/libc/src/base64.c

--1:000000000000
+:0626c2606dc3
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#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;
+}

The Tor Browser / file comparison

comparison: nsprpub/lib/libc/src/base64.c

nsprpub/lib/libc/src/base64.c