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+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2009, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+/* Base64 encoding/decoding
+ *
+ * Test harnesses down the bottom - compile with -DTEST_ENCODE for
+ * a program that will read in raw data from stdin and write out
+ * a base64-encoded version to stdout, and the length returned by the
+ * encoding function to stderr. Compile with -DTEST_DECODE for a program that
+ * will go the other way.
+ *
+ * This code will break if int is smaller than 32 bits
+ */
+
+#include "setup.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#define _MPRINTF_REPLACE /* use our functions only */
+#include <curl/mprintf.h>
+
+#include "urldata.h" /* for the SessionHandle definition */
+#include "easyif.h" /* for Curl_convert_... prototypes */
+#include "warnless.h"
+#include "curl_base64.h"
+#include "curl_memory.h"
+
+/* include memdebug.h last */
+#include "memdebug.h"
+
+/* ---- Base64 Encoding/Decoding Table --- */
+static const char table64[]=
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+static void decodeQuantum(unsigned char *dest, const char *src)
+{
+ const char *s, *p;
+ unsigned long i, v, x = 0;
+
+ for(i = 0, s = src; i < 4; i++, s++) {
+ v = 0;
+ p = table64;
+ while(*p && (*p != *s)) {
+ v++;
+ p++;
+ }
+ if(*p == *s)
+ x = (x << 6) + v;
+ else if(*s == '=')
+ x = (x << 6);
+ }
+
+ dest[2] = curlx_ultouc(x);
+ x >>= 8;
+ dest[1] = curlx_ultouc(x);
+ x >>= 8;
+ dest[0] = curlx_ultouc(x);
+}
+
+/*
+ * Curl_base64_decode()
+ *
+ * Given a base64 string at src, decode it and return an allocated memory in
+ * the *outptr. Returns the length of the decoded data.
+ */
+size_t Curl_base64_decode(const char *src, unsigned char **outptr)
+{
+ size_t length = 0;
+ size_t equalsTerm = 0;
+ size_t i;
+ size_t numQuantums;
+ unsigned char lastQuantum[3];
+ size_t rawlen = 0;
+ unsigned char *newstr;
+
+ *outptr = NULL;
+
+ while((src[length] != '=') && src[length])
+ length++;
+ /* A maximum of two = padding characters is allowed */
+ if(src[length] == '=') {
+ equalsTerm++;
+ if(src[length+equalsTerm] == '=')
+ equalsTerm++;
+ }
+ numQuantums = (length + equalsTerm) / 4;
+
+ /* Don't allocate a buffer if the decoded length is 0 */
+ if(numQuantums == 0)
+ return 0;
+
+ rawlen = (numQuantums * 3) - equalsTerm;
+
+ /* The buffer must be large enough to make room for the last quantum
+ (which may be partially thrown out) and the zero terminator. */
+ newstr = malloc(rawlen+4);
+ if(!newstr)
+ return 0;
+
+ *outptr = newstr;
+
+ /* Decode all but the last quantum (which may not decode to a
+ multiple of 3 bytes) */
+ for(i = 0; i < numQuantums - 1; i++) {
+ decodeQuantum(newstr, src);
+ newstr += 3; src += 4;
+ }
+
+ /* This final decode may actually read slightly past the end of the buffer
+ if the input string is missing pad bytes. This will almost always be
+ harmless. */
+ decodeQuantum(lastQuantum, src);
+ for(i = 0; i < 3 - equalsTerm; i++)
+ newstr[i] = lastQuantum[i];
+
+ newstr[i] = '\0'; /* zero terminate */
+ return rawlen;
+}
+
+/*
+ * Curl_base64_encode()
+ *
+ * Returns the length of the newly created base64 string. The third argument
+ * is a pointer to an allocated area holding the base64 data. If something
+ * went wrong, 0 is returned.
+ *
+ */
+size_t Curl_base64_encode(struct SessionHandle *data,
+ const char *inputbuff, size_t insize,
+ char **outptr)
+{
+ unsigned char ibuf[3];
+ unsigned char obuf[4];
+ int i;
+ int inputparts;
+ char *output;
+ char *base64data;
+#ifdef CURL_DOES_CONVERSIONS
+ char *convbuf = NULL;
+#endif
+
+ const char *indata = inputbuff;
+
+ *outptr = NULL; /* set to NULL in case of failure before we reach the end */
+
+ if(0 == insize)
+ insize = strlen(indata);
+
+ base64data = output = malloc(insize*4/3+4);
+ if(NULL == output)
+ return 0;
+
+#ifdef CURL_DOES_CONVERSIONS
+ /*
+ * The base64 data needs to be created using the network encoding
+ * not the host encoding. And we can't change the actual input
+ * so we copy it to a buffer, translate it, and use that instead.
+ */
+ if(data) {
+ convbuf = malloc(insize);
+ if(!convbuf) {
+ free(output);
+ return 0;
+ }
+ memcpy(convbuf, indata, insize);
+ if(CURLE_OK != Curl_convert_to_network(data, convbuf, insize)) {
+ free(convbuf);
+ free(output);
+ return 0;
+ }
+ indata = convbuf; /* switch to the converted buffer */
+ }
+#else
+ (void)data;
+#endif
+
+ while(insize > 0) {
+ for (i = inputparts = 0; i < 3; i++) {
+ if(insize > 0) {
+ inputparts++;
+ ibuf[i] = (unsigned char) *indata;
+ indata++;
+ insize--;
+ }
+ else
+ ibuf[i] = 0;
+ }
+
+ obuf[0] = (unsigned char) ((ibuf[0] & 0xFC) >> 2);
+ obuf[1] = (unsigned char) (((ibuf[0] & 0x03) << 4) | \
+ ((ibuf[1] & 0xF0) >> 4));
+ obuf[2] = (unsigned char) (((ibuf[1] & 0x0F) << 2) | \
+ ((ibuf[2] & 0xC0) >> 6));
+ obuf[3] = (unsigned char) (ibuf[2] & 0x3F);
+
+ switch(inputparts) {
+ case 1: /* only one byte read */
+ snprintf(output, 5, "%c%c==",
+ table64[obuf[0]],
+ table64[obuf[1]]);
+ break;
+ case 2: /* two bytes read */
+ snprintf(output, 5, "%c%c%c=",
+ table64[obuf[0]],
+ table64[obuf[1]],
+ table64[obuf[2]]);
+ break;
+ default:
+ snprintf(output, 5, "%c%c%c%c",
+ table64[obuf[0]],
+ table64[obuf[1]],
+ table64[obuf[2]],
+ table64[obuf[3]] );
+ break;
+ }
+ output += 4;
+ }
+ *output=0;
+ *outptr = base64data; /* make it return the actual data memory */
+
+#ifdef CURL_DOES_CONVERSIONS
+ if(data)
+ free(convbuf);
+#endif
+ return strlen(base64data); /* return the length of the new data */
+}
+/* ---- End of Base64 Encoding ---- */
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