quickjs-tart

escape.c (6299B)

---

 /***************************************************************************
  *                                  _   _ ____  _
  *  Project                     ___| | | |  _ \| |
  *                             / __| | | | |_) | |
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
  * Copyright (C) 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 https://curl.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.
  *
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
 
 /* Escape and unescape URL encoding in strings. The functions return a new
  * allocated string or NULL if an error occurred.  */
 
 #include "curl_setup.h"
 
 #include <curl/curl.h>
 
 struct Curl_easy;
 
 #include "urldata.h"
 #include "curlx/warnless.h"
 #include "escape.h"
 #include "strdup.h"
 #include "curlx/strparse.h"
 
 /* The last 3 #include files should be in this order */
 #include "curl_printf.h"
 #include "curl_memory.h"
 #include "memdebug.h"
 
 /* for ABI-compatibility with previous versions */
 char *curl_escape(const char *string, int inlength)
 {
   return curl_easy_escape(NULL, string, inlength);
 }
 
 /* for ABI-compatibility with previous versions */
 char *curl_unescape(const char *string, int length)
 {
   return curl_easy_unescape(NULL, string, length, NULL);
 }
 
 /* Escapes for URL the given unescaped string of given length.
  * 'data' is ignored since 7.82.0.
  */
 char *curl_easy_escape(CURL *data, const char *string,
                        int inlength)
 {
   size_t length;
   struct dynbuf d;
   (void)data;
 
   if(!string || (inlength < 0))
     return NULL;
 
   length = (inlength ? (size_t)inlength : strlen(string));
   if(!length)
     return strdup("");
 
   curlx_dyn_init(&d, length * 3 + 1);
 
   while(length--) {
     /* treat the characters unsigned */
     unsigned char in = (unsigned char)*string++;
 
     if(ISUNRESERVED(in)) {
       /* append this */
       if(curlx_dyn_addn(&d, &in, 1))
         return NULL;
     }
     else {
       /* encode it */
       unsigned char out[3]={'%'};
       Curl_hexbyte(&out[1], in);
       if(curlx_dyn_addn(&d, out, 3))
         return NULL;
     }
   }
 
   return curlx_dyn_ptr(&d);
 }
 
 /*
  * Curl_urldecode() URL decodes the given string.
  *
  * Returns a pointer to a malloced string in *ostring with length given in
  * *olen. If length == 0, the length is assumed to be strlen(string).
  *
  * ctrl options:
  * - REJECT_NADA: accept everything
  * - REJECT_CTRL: rejects control characters (byte codes lower than 32) in
  *                the data
  * - REJECT_ZERO: rejects decoded zero bytes
  *
  * The values for the enum starts at 2, to make the assert detect legacy
  * invokes that used TRUE/FALSE (0 and 1).
  */
 
 CURLcode Curl_urldecode(const char *string, size_t length,
                         char **ostring, size_t *olen,
                         enum urlreject ctrl)
 {
   size_t alloc;
   char *ns;
 
   DEBUGASSERT(string);
   DEBUGASSERT(ctrl >= REJECT_NADA); /* crash on TRUE/FALSE */
 
   alloc = (length ? length : strlen(string));
   ns = malloc(alloc + 1);
 
   if(!ns)
     return CURLE_OUT_OF_MEMORY;
 
   /* store output string */
   *ostring = ns;
 
   while(alloc) {
     unsigned char in = (unsigned char)*string;
     if(('%' == in) && (alloc > 2) &&
        ISXDIGIT(string[1]) && ISXDIGIT(string[2])) {
       /* this is two hexadecimal digits following a '%' */
       in = (unsigned char)((Curl_hexval(string[1]) << 4) |
                            Curl_hexval(string[2]));
       string += 3;
       alloc -= 3;
     }
     else {
       string++;
       alloc--;
     }
 
     if(((ctrl == REJECT_CTRL) && (in < 0x20)) ||
        ((ctrl == REJECT_ZERO) && (in == 0))) {
       Curl_safefree(*ostring);
       return CURLE_URL_MALFORMAT;
     }
 
     *ns++ = (char)in;
   }
   *ns = 0; /* terminate it */
 
   if(olen)
     /* store output size */
     *olen = ns - *ostring;
 
   return CURLE_OK;
 }
 
 /*
  * Unescapes the given URL escaped string of given length. Returns a
  * pointer to a malloced string with length given in *olen.
  * If length == 0, the length is assumed to be strlen(string).
  * If olen == NULL, no output length is stored.
  * 'data' is ignored since 7.82.0.
  */
 char *curl_easy_unescape(CURL *data, const char *string,
                          int length, int *olen)
 {
   char *str = NULL;
   (void)data;
   if(string && (length >= 0)) {
     size_t inputlen = (size_t)length;
     size_t outputlen;
     CURLcode res = Curl_urldecode(string, inputlen, &str, &outputlen,
                                   REJECT_NADA);
     if(res)
       return NULL;
 
     if(olen) {
       if(outputlen <= (size_t) INT_MAX)
         *olen = curlx_uztosi(outputlen);
       else
         /* too large to return in an int, fail! */
         Curl_safefree(str);
     }
   }
   return str;
 }
 
 /* For operating systems/environments that use different malloc/free
    systems for the app and for this library, we provide a free that uses
    the library's memory system */
 void curl_free(void *p)
 {
   free(p);
 }
 
 /*
  * Curl_hexencode()
  *
  * Converts binary input to lowercase hex-encoded ASCII output.
  * Null-terminated.
  */
 void Curl_hexencode(const unsigned char *src, size_t len, /* input length */
                     unsigned char *out, size_t olen) /* output buffer size */
 {
   DEBUGASSERT(src && len && (olen >= 3));
   if(src && len && (olen >= 3)) {
     while(len-- && (olen >= 3)) {
       out[0] = Curl_ldigits[*src >> 4];
       out[1] = Curl_ldigits[*src & 0x0F];
       ++src;
       out += 2;
       olen -= 2;
     }
     *out = 0;
   }
   else if(olen)
     *out = 0;
 }
 
 /* Curl_hexbyte
  *
  * Output a single unsigned char as a two-digit UPPERCASE hex number.
  */
 void Curl_hexbyte(unsigned char *dest, /* must fit two bytes */
                   unsigned char val)
 {
   dest[0] = Curl_udigits[val >> 4];
   dest[1] = Curl_udigits[val & 0x0F];
 }