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-rw-r--r--lib/dotdot.c170
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diff --git a/lib/dotdot.c b/lib/dotdot.c
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+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2013, 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.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+
+#include "dotdot.h"
+
+#include "curl_memory.h"
+/* The last #include file should be: */
+#include "memdebug.h"
+
+/*
+ * "Remove Dot Segments"
+ * http://tools.ietf.org/html/rfc3986#section-5.2.4
+ */
+
+/*
+ * Curl_dedotdotify()
+ *
+ * This function gets a zero-terminated path with dot and dotdot sequences
+ * passed in and strips them off according to the rules in RFC 3986 section
+ * 5.2.5.
+ *
+ * The function handles a query part ('?' + stuff) appended but it expects
+ * that fragments ('#' + stuff) have already been cut off.
+ *
+ * RETURNS
+ *
+ * an allocated dedotdotified output string
+ */
+char *Curl_dedotdotify(char *input)
+{
+ size_t inlen = strlen(input);
+ char *clone;
+ size_t clen = inlen; /* the length of the cloned input */
+ char *out = malloc(inlen+1);
+ char *outp;
+ char *orgclone;
+ char *queryp;
+ if(!out)
+ return NULL; /* out of memory */
+
+ /* get a cloned copy of the input */
+ clone = strdup(input);
+ if(!clone) {
+ free(out);
+ return NULL;
+ }
+ orgclone = clone;
+ outp = out;
+
+ /*
+ * To handle query-parts properly, we must find it and remove it during the
+ * dotdot-operation and then append it again at the end to the output
+ * string.
+ */
+ queryp = strchr(clone, '?');
+ if(queryp)
+ *queryp = 0;
+
+ do {
+
+ /* A. If the input buffer begins with a prefix of "../" or "./", then
+ remove that prefix from the input buffer; otherwise, */
+
+ if(!strncmp("./", clone, 2)) {
+ clone+=2;
+ clen-=2;
+ }
+ else if(!strncmp("../", clone, 3)) {
+ clone+=3;
+ clen-=3;
+ }
+
+ /* B. if the input buffer begins with a prefix of "/./" or "/.", where
+ "." is a complete path segment, then replace that prefix with "/" in
+ the input buffer; otherwise, */
+ else if(!strncmp("/./", clone, 3)) {
+ clone+=2;
+ clen-=2;
+ }
+ else if(!strcmp("/.", clone)) {
+ clone[1]='/';
+ clone++;
+ clen-=1;
+ }
+
+ /* C. if the input buffer begins with a prefix of "/../" or "/..", where
+ ".." is a complete path segment, then replace that prefix with "/" in
+ the input buffer and remove the last segment and its preceding "/" (if
+ any) from the output buffer; otherwise, */
+
+ else if(!strncmp("/../", clone, 4)) {
+ clone+=3;
+ clen-=3;
+ /* remove the last segment from the output buffer */
+ while(outp > out) {
+ outp--;
+ if(*outp == '/')
+ break;
+ }
+ *outp = 0; /* zero-terminate where it stops */
+ }
+ else if(!strcmp("/..", clone)) {
+ clone[2]='/';
+ clone+=2;
+ clen-=2;
+ /* remove the last segment from the output buffer */
+ while(outp > out) {
+ outp--;
+ if(*outp == '/')
+ break;
+ }
+ *outp = 0; /* zero-terminate where it stops */
+ }
+
+ /* D. if the input buffer consists only of "." or "..", then remove
+ that from the input buffer; otherwise, */
+
+ else if(!strcmp(".", clone) || !strcmp("..", clone)) {
+ *clone=0;
+ }
+
+ else {
+ /* E. move the first path segment in the input buffer to the end of
+ the output buffer, including the initial "/" character (if any) and
+ any subsequent characters up to, but not including, the next "/"
+ character or the end of the input buffer. */
+
+ do {
+ *outp++ = *clone++;
+ clen--;
+ } while(*clone && (*clone != '/'));
+ *outp=0;
+ }
+
+ } while(*clone);
+
+ if(queryp) {
+ size_t qlen;
+ /* There was a query part, append that to the output. The 'clone' string
+ may now have been altered so we copy from the original input string
+ from the correct index. */
+ size_t oindex = queryp - orgclone;
+ qlen = strlen(&input[oindex]);
+ memcpy(outp, &input[oindex], qlen+1); /* include the ending zero byte */
+ }
+
+ free(orgclone);
+ return out;
+}