/* Copyright (c) 1996 by 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.
 */

#include <apr.h>
#include <apr_network_io.h>

#if APR_HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#if APR_HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if APR_HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if APR_HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#include <string.h>
#if APR_HAVE_ERRNO_H
#include <errno.h>
#endif

#include "serf_private.h"

#ifndef IN6ADDRSZ
#define IN6ADDRSZ 16
#endif

#ifndef INADDRSZ
#define INADDRSZ  4
#endif

#ifndef INT16SZ
#define INT16SZ   sizeof(apr_int16_t)
#endif

/* int
 * inet_pton4(src, dst)
 *  like inet_aton() but without all the hexadecimal and shorthand.
 * return:
 *  1 if `src' is a valid dotted quad, else 0.
 * notice:
 *  does not touch `dst' unless it's returning 1.
 * author:
 *  Paul Vixie, 1996.
 */
int serf__inet_pton4(const char *src, unsigned char *dst)
{
  static const char digits[] = "0123456789";
  int saw_digit, octets, ch;
  unsigned char tmp[INADDRSZ], *tp;

  saw_digit = 0;
  octets = 0;
  *(tp = tmp) = 0;
  while ((ch = *src++) != '\0') {
    const char *pch;

    if ((pch = strchr(digits, ch)) != NULL) {
      unsigned int new = *tp * 10 + (unsigned int)(pch - digits);

      if (new > 255)
        return (0);
      *tp = new;
      if (!saw_digit) {
        if (++octets > 4)
          return (0);
        saw_digit = 1;
      }
    } else if (ch == '.' && saw_digit) {
      if (octets == 4)
        return (0);
      *++tp = 0;
      saw_digit = 0;
    } else
      return (0);
  }
  if (octets < 4)
    return (0);

  memcpy(dst, tmp, INADDRSZ);
  return (1);
}


/* int
 * inet_pton6(src, dst)
 *  convert presentation level address to network order binary form.
 * return:
 *  1 if `src' is a valid [RFC1884 2.2] address, else 0.
 * notice:
 *  (1) does not touch `dst' unless it's returning 1.
 *  (2) :: in a full address is silently ignored.
 * credit:
 *  inspired by Mark Andrews.
 * author:
 *  Paul Vixie, 1996.
 */
int serf__inet_pton6(const char *src, unsigned char *dst)
{
  static const char xdigits_l[] = "0123456789abcdef",
                    xdigits_u[] = "0123456789ABCDEF";
  unsigned char tmp[IN6ADDRSZ], *tp, *endp, *colonp;
  const char *xdigits, *curtok;
  int ch, saw_xdigit;
  apr_uint32_t val;

  memset((tp = tmp), '\0', IN6ADDRSZ);
  endp = tp + IN6ADDRSZ;
  colonp = NULL;
  /* Leading :: requires some special handling. */
  if (*src == ':')
    if (*++src != ':')
      return (0);
  curtok = src;
  saw_xdigit = 0;
  val = 0;
  while ((ch = *src++) != '\0') {
    const char *pch;

    if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
      pch = strchr((xdigits = xdigits_u), ch);
    if (pch != NULL) {
      val <<= 4;
      val |= (pch - xdigits);
      if (val > 0xffff)
        return (0);
      saw_xdigit = 1;
      continue;
    }
    if (ch == ':') {
      curtok = src;
      if (!saw_xdigit) {
        if (colonp)
          return (0);
        colonp = tp;
        continue;
      }
      if (tp + INT16SZ > endp)
        return (0);
      *tp++ = (unsigned char)(val >> 8) & 0xff;
      *tp++ = (unsigned char)val & 0xff;
      saw_xdigit = 0;
      val = 0;
      continue;
    }
    if (ch == '.' && ((tp + INADDRSZ) <= endp)
        && serf__inet_pton4(curtok, tp) > 0) {
      tp += INADDRSZ;
      saw_xdigit = 0;
      break; /* '\0' was seen by inet_pton4(). */
    }
    return (0);
  }
  if (saw_xdigit) {
    if (tp + INT16SZ > endp)
      return (0);
    *tp++ = (unsigned char)(val >> 8) & 0xff;
    *tp++ = (unsigned char)val & 0xff;
  }
  if (colonp != NULL) {
    /*
     * Since some memmove()'s erroneously fail to handle
     * overlapping regions, we'll do the shift by hand.
     */
    const apr_ssize_t n = tp - colonp;
    apr_ssize_t i;

    for (i = 1; i <= n; i++) {
      endp[-i] = colonp[n - i];
      colonp[n - i] = 0;
    }
    tp = endp;
  }
  if (tp != endp)
    return (0);
  memcpy(dst, tmp, IN6ADDRSZ);
  return (1);
}