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-rw-r--r--nsprpub/lib/libc/src/base64.c416
1 files changed, 416 insertions, 0 deletions
diff --git a/nsprpub/lib/libc/src/base64.c b/nsprpub/lib/libc/src/base64.c
new file mode 100644
index 000000000..07a4902f5
--- /dev/null
+++ b/nsprpub/lib/libc/src/base64.c
@@ -0,0 +1,416 @@
+/* -*- 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;
+}
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