quickjs-tart

inet_ntop.c (6354B)

---

 /*
  * Copyright (C) 1996-2022  Internet Software Consortium.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *
  * SPDX-License-Identifier: ISC
  */
 /*
  * Original code by Paul Vixie. "curlified" by Gisle Vanem.
  */
 
 #include "../curl_setup.h"
 
 #ifndef HAVE_INET_NTOP
 
 #ifdef HAVE_SYS_PARAM_H
 #include <sys/param.h>
 #endif
 #ifdef HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
 #ifdef HAVE_ARPA_INET_H
 #include <arpa/inet.h>
 #endif
 
 #include "inet_ntop.h"
 
 #define IN6ADDRSZ       16
 /* #define INADDRSZ         4 */
 #define INT16SZ          2
 
 /*
  * If USE_IPV6 is disabled, we still want to parse IPv6 addresses, so make
  * sure we have _some_ value for AF_INET6 without polluting our fake value
  * everywhere.
  */
 #if !defined(USE_IPV6) && !defined(AF_INET6)
 #define AF_INET6 (AF_INET + 1)
 #endif
 
 /*
  * Format an IPv4 address, more or less like inet_ntop().
  *
  * Returns `dst' (as a const)
  * Note:
  *  - uses no statics
  *  - takes an unsigned char* not an in_addr as input
  */
 static char *inet_ntop4(const unsigned char *src, char *dst, size_t size)
 {
   char tmp[sizeof("255.255.255.255")];
   size_t len;
 
   DEBUGASSERT(size >= 16);
 
   /* this sprintf() does not overflow the buffer. Avoids snprintf to work more
      widely. Avoids the msnprintf family to work as a curlx function. */
   (void)(sprintf)(tmp, "%d.%d.%d.%d",
                   ((int)((unsigned char)src[0])) & 0xff,
                   ((int)((unsigned char)src[1])) & 0xff,
                   ((int)((unsigned char)src[2])) & 0xff,
                   ((int)((unsigned char)src[3])) & 0xff);
 
   len = strlen(tmp);
   if(len == 0 || len >= size) {
 #ifdef USE_WINSOCK
     CURL_SETERRNO(WSAEINVAL);
 #else
     CURL_SETERRNO(ENOSPC);
 #endif
     return NULL;
   }
   strcpy(dst, tmp);
   return dst;
 }
 
 /*
  * Convert IPv6 binary address into presentation (printable) format.
  */
 static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
 {
   /*
    * Note that int32_t and int16_t need only be "at least" large enough
    * to contain a value of the specified size. On some systems, like
    * Crays, there is no such thing as an integer variable with 16 bits.
    * Keep this in mind if you think this function should have been coded
    * to use pointer overlays. All the world's not a VAX.
    */
   char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")];
   char *tp;
   struct {
     int base;
     int len;
   } best, cur;
   unsigned int words[IN6ADDRSZ / INT16SZ];
   int i;
 
   /* Preprocess:
    *  Copy the input (bytewise) array into a wordwise array.
    *  Find the longest run of 0x00's in src[] for :: shorthanding.
    */
   memset(words, '\0', sizeof(words));
   for(i = 0; i < IN6ADDRSZ; i++)
     words[i/2] |= ((unsigned int)src[i] << ((1 - (i % 2)) << 3));
 
   best.base = -1;
   cur.base  = -1;
   best.len = 0;
   cur.len = 0;
 
   for(i = 0; i < (IN6ADDRSZ / INT16SZ); i++) {
     if(words[i] == 0) {
       if(cur.base == -1) {
         cur.base = i; cur.len = 1;
       }
       else
         cur.len++;
     }
     else if(cur.base != -1) {
       if(best.base == -1 || cur.len > best.len)
         best = cur;
       cur.base = -1;
     }
   }
   if((cur.base != -1) && (best.base == -1 || cur.len > best.len))
     best = cur;
   if(best.base != -1 && best.len < 2)
     best.base = -1;
   /* Format the result. */
   tp = tmp;
   for(i = 0; i < (IN6ADDRSZ / INT16SZ); i++) {
     /* Are we inside the best run of 0x00's? */
     if(best.base != -1 && i >= best.base && i < (best.base + best.len)) {
       if(i == best.base)
         *tp++ = ':';
       continue;
     }
 
     /* Are we following an initial run of 0x00s or any real hex?
      */
     if(i)
       *tp++ = ':';
 
     /* Is this address an encapsulated IPv4?
      */
     if(i == 6 && best.base == 0 &&
         (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
       if(!inet_ntop4(src + 12, tp, sizeof(tmp) - (tp - tmp))) {
         return NULL;
       }
       tp += strlen(tp);
       break;
     }
     else {
       /* Lower-case digits. Can't use the set from mprintf.c since this
          needs to work as a curlx function */
       static const unsigned char ldigits[] = "0123456789abcdef";
 
       unsigned int w = words[i];
       /* output lowercase 16bit hex number but ignore leading zeroes */
       if(w & 0xf000)
         *tp++ = ldigits[(w & 0xf000) >> 12];
       if(w & 0xff00)
         *tp++ = ldigits[(w & 0x0f00) >> 8];
       if(w & 0xfff0)
         *tp++ = ldigits[(w & 0x00f0) >> 4];
       *tp++ = ldigits[(w & 0x000f)];
     }
   }
 
   /* Was it a trailing run of 0x00's?
    */
   if(best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ))
     *tp++ = ':';
   *tp++ = '\0';
 
   /* Check for overflow, copy, and we are done.
    */
   if((size_t)(tp - tmp) > size) {
 #ifdef USE_WINSOCK
     CURL_SETERRNO(WSAEINVAL);
 #else
     CURL_SETERRNO(ENOSPC);
 #endif
     return NULL;
   }
   strcpy(dst, tmp);
   return dst;
 }
 
 /*
  * Convert a network format address to presentation format.
  *
  * Returns pointer to presentation format address (`buf').
  * Returns NULL on error and errno set with the specific
  * error, EAFNOSUPPORT or ENOSPC.
  *
  * On Windows we store the error in the thread errno, not in the Winsock error
  * code. This is to avoid losing the actual last Winsock error. When this
  * function returns NULL, check errno not SOCKERRNO.
  */
 char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size)
 {
   switch(af) {
   case AF_INET:
     return inet_ntop4((const unsigned char *)src, buf, size);
   case AF_INET6:
     return inet_ntop6((const unsigned char *)src, buf, size);
   default:
     CURL_SETERRNO(SOCKEAFNOSUPPORT);
     return NULL;
   }
 }
 #endif  /* HAVE_INET_NTOP */