adig.c

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/* Copyright 1998 by the Massachusetts Institute of Technology.
 *
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting
 * documentation, and that the name of M.I.T. not be used in
 * advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.
 * M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is"
 * without express or implied warranty.
 */
 
#include <sys/types.h>
 
#ifdef WIN32
#include <winsock2.h>
#include <stdlib.h>
#include <io.h>
#else
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "ares_nameser.h"
#include <unistd.h>
#include <netdb.h>
#endif
 
#include "rutil/ResipAssert.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
 
#include <errno.h>
 
#include "ares.h"
#include "ares_dns.h"
#include "ares_compat.h"
 
#if defined(WIN32) || defined(__QNX__)
#define strcasecmp(a,b) stricmp(a,b)
#define strncasecmp(a,b,c) strnicmp(a,b,c)
#endif
 
 
#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff
#endif
 
extern int optind;
extern char *optarg;
 
struct nv {
  const char *name;
  int value;
};
 
static const struct nv flags[] = {
  { "usevc",        ARES_FLAG_USEVC },
  { "primary",      ARES_FLAG_PRIMARY },
  { "igntc",        ARES_FLAG_IGNTC },
  { "norecurse",    ARES_FLAG_NORECURSE },
  { "stayopen",     ARES_FLAG_STAYOPEN },
  { "noaliases",    ARES_FLAG_NOALIASES }
};
static const int nflags = sizeof(flags) / sizeof(flags[0]);
 
static const struct nv classes[] = {
  { "IN",   C_IN },
  { "CHAOS",    C_CHAOS },
  { "HS",   C_HS },
  { "ANY",  C_ANY }
};
static const int nclasses = sizeof(classes) / sizeof(classes[0]);
 
static const struct nv types[] = {
  { "A",    T_A },
  { "NS",   T_NS },
  { "MD",   T_MD },
  { "MF",   T_MF },
  { "CNAME",    T_CNAME },
  { "SOA",  T_SOA },
  { "MB",   T_MB },
  { "MG",   T_MG },
  { "MR",   T_MR },
  { "NULL", T_NULL },
  { "WKS",  T_WKS },
  { "PTR",  T_PTR },
  { "HINFO",    T_HINFO },
  { "MINFO",    T_MINFO },
  { "MX",   T_MX },
  { "TXT",  T_TXT },
  { "RP",   T_RP },
  { "AFSDB",    T_AFSDB },
  { "X25",  T_X25 },
  { "ISDN", T_ISDN },
  { "RT",   T_RT },
  { "NSAP", T_NSAP },
  { "NSAP_PTR", T_NSAP_PTR },
  { "SIG",  T_SIG },
  { "KEY",  T_KEY },
  { "PX",   T_PX },
  { "GPOS", T_GPOS },
  { "AAAA", T_AAAA },
  { "LOC",  T_LOC },
  { "SRV",  T_SRV },
  { "AXFR", T_AXFR },
  { "MAILB",    T_MAILB },
  { "MAILA",    T_MAILA },
  { "NAPTR",    T_NAPTR },
  { "ANY",  T_ANY }
};
static const int ntypes = sizeof(types) / sizeof(types[0]);
 
static const char *opcodes[] = {
  "QUERY", "IQUERY", "STATUS", "(reserved)", "NOTIFY",
  "(unknown)", "(unknown)", "(unknown)", "(unknown)",
  "UPDATEA", "UPDATED", "UPDATEDA", "UPDATEM", "UPDATEMA",
  "ZONEINIT", "ZONEREF"
};
 
static const char *rcodes[] = {
  "NOERROR", "FORMERR", "SERVFAIL", "NXDOMAIN", "NOTIMP", "REFUSED",
  "(unknown)", "(unknown)", "(unknown)", "(unknown)", "(unknown)",
  "(unknown)", "(unknown)", "(unknown)", "(unknown)", "NOCHANGE"
};
 
static void callback(void *arg, int status, unsigned char *abuf, int alen);
static const unsigned char *display_question(const unsigned char *aptr,
                         const unsigned char *abuf,
                         int alen);
static const unsigned char *display_rr(const unsigned char *aptr,
                       const unsigned char *abuf, int alen);
static const char *type_name(int type);
static const char *class_name(int dnsclass);
static void usage(void);
 
#ifdef WIN32
struct option
{
      const char *name;
      int has_arg;
      int *flag;
      int val;
};
 
char *optarg = 0;
int optind = 0;
 
int getopt(int argc,    
                      char *  argv[],
                       char *optstring )
{
   static int carg = 0;
   //static int nextchar = 0;
     char * p;
 
   carg++;
   if ( carg >= argc ) return -1;
 
 p = argv[carg];
   //register int al = strlen(argv[carg]);
 
   if (*p  == '-' && isalnum((unsigned char)*(p+1)))
   {
      char o = *(p+1);
     int i,l;
 
       l =  (int)strlen(optstring);
 
      for( i = 0 ; i < l; i++)
      {
 
         if (optstring[i] == ':') continue;
 
         if ( optstring[i] == o )   // match option char
         {
    
            if ( optstring[i+1] == ':' ) // arg option
            {
               optind = ++carg;
               optarg = argv[optind];
 
            }
            else
            {
               optind = 0;
               optarg = 0;
            }
            return (int)o;
         }
 
      }
 
      return (int)'?';
   }
   return (int)'?';
}
#endif
 
int main(int argc, char **argv)
{
  ares_channel channel;
  int c, i, optmask = ARES_OPT_FLAGS, dnsclass = C_IN, type = T_A;
  int status, nfds, count;
  struct ares_options options;
  fd_set read_fds, write_fds;
  struct timeval *tvp, tv;
 
#ifdef WIN32 
   WORD wVersionRequested = MAKEWORD( 2, 2 );
   WSADATA wsaData;
   int err;
 
   err = WSAStartup( wVersionRequested, &wsaData );
   if ( err != 0 ) 
   {
      // could not find a usable WinSock DLL
      //cerr << "Could not load winsock" << endl;
      resip_assert(0); // is this is failing, try a different version that 2.2, 1.0 or later will likely work 
      exit(1);
   }
    
   /* Confirm that the WinSock DLL supports 2.2.*/
   /* Note that if the DLL supports versions greater    */
   /* than 2.2 in addition to 2.2, it will still return */
   /* 2.2 in wVersion since that is the version we      */
   /* requested.                                        */
    
   if ( LOBYTE( wsaData.wVersion ) != 2 ||
        HIBYTE( wsaData.wVersion ) != 2 ) 
   {
      /* Tell the user that we could not find a usable */
      /* WinSock DLL.                                  */
      WSACleanup( );
      //cerr << "Bad winsock verion" << endl;
      resip_assert(0); // is this is failing, try a different version that 2.2, 1.0 or later will likely work 
      exit(1);
   }  
#endif
 
    options.flags = ARES_FLAG_NOCHECKRESP;
  options.servers = NULL;
  options.nservers = 0;
 
  while ((c = getopt(argc, argv, "f:s:c:t:T:U:")) != -1)
    {
      switch (c)
    {
    case 'f':
      /* Add a flag. */
      for (i = 0; i < nflags; i++)
        {
          if (strcmp(flags[i].name, optarg) == 0)
        break;
        }
      if (i == nflags)
        usage();
      options.flags |= flags[i].value;
      break;
 
   case 's':
   /* Add a server, and specify servers in the option mask. */
   {
      struct addrinfo hints = { 0 };
      struct addrinfo* res = NULL;
      hints.ai_family = AF_INET;
      hints.ai_socktype = SOCK_STREAM;
      if (getaddrinfo(optarg, NULL, &hints, &res) != 0 || res == NULL)
      {
         fprintf(stderr, "adig: server %s not found.\n", optarg);
         return 1;
      }
      options.servers = realloc(options.servers, (options.nservers + 1)
         * sizeof(struct in_addr));
      if (!options.servers)
      {
         freeaddrinfo(res);
         fprintf(stderr, "Out of memory!\n");
         return 1;
      }
      memcpy(&options.servers[options.nservers],
         &((struct sockaddr_in*)res->ai_addr)->sin_addr,
         sizeof(struct in_addr));
      freeaddrinfo(res);
      options.nservers++;
      optmask |= ARES_OPT_SERVERS;
   }
   break;
 
    case 'c':
      /* Set the query class. */
      for (i = 0; i < nclasses; i++)
        {
          if (strcasecmp(classes[i].name, optarg) == 0)
        break;
        }
      if (i == nclasses)
        usage();
      dnsclass = classes[i].value;
      break;
 
    case 't':
      /* Set the query type. */
      for (i = 0; i < ntypes; i++)
        {
          if (strcasecmp(types[i].name, optarg) == 0)
        break;
        }
      if (i == ntypes)
        usage();
      type = types[i].value;
      break;
 
    case 'T':
      /* Set the TCP port number. */
      if (!isdigit((unsigned char)*optarg))
        usage();
      options.tcp_port = (unsigned short)strtol(optarg, NULL, 0);
      optmask |= ARES_OPT_TCP_PORT;
      break;
 
    case 'U':
      /* Set the UDP port number. */
      if (!isdigit((unsigned char)*optarg))
        usage();
      options.udp_port = (unsigned short)strtol(optarg, NULL, 0);
      optmask |= ARES_OPT_UDP_PORT;
      break;
    }
    }
  argc -= optind;
  argv += optind;
  if (argc == 0)
    usage();
 
  status = ares_init_options(&channel, &options, optmask);
  if (status != ARES_SUCCESS)
    {
      fprintf(stderr, "ares_init_options: %s\n",
              ares_strerror(status));
      return 1;
    }
 
  /* Initiate the queries, one per command-line argument.  If there is
   * only one query to do, supply NULL as the callback argument;
   * otherwise, supply the query name as an argument so we can
   * distinguish responses for the user when printing them out.
   */
  if (argc == 1)
    ares_query(channel, *argv, dnsclass, type, callback, (char *) NULL);
  else
    {
      for (; *argv; argv++)
    ares_query(channel, *argv, dnsclass, type, callback, *argv);
    }
 
  /* Wait for all queries to complete. */
  while (1)
    {
      FD_ZERO(&read_fds);
      FD_ZERO(&write_fds);
      nfds = ares_fds(channel, &read_fds, &write_fds);
      if (nfds == 0)
    break;
      tvp = ares_timeout(channel, NULL, &tv);
      count = select(nfds, &read_fds, &write_fds, NULL, tvp);
      if (count < 0 && errno != EINVAL)
    {
      perror("select");
      return 1;
    }
      ares_process(channel, &read_fds, &write_fds);
    }
 
  ares_destroy(channel);
  return 0;
}
 
static void callback(void *arg, int status, unsigned char *abuf, int alen)
{
  char *name = (char *) arg;
  int id, qr, opcode, aa, tc, rd, ra, rcode, i;
  unsigned int qdcount, ancount, nscount, arcount;
  const unsigned char *aptr;
 
  /* Display the query name if given. */
  if (name)
    printf("Answer for query %s:\n", name);
 
  /* Display an error message if there was an error, but only stop if
   * we actually didn't get an answer buffer.
   */
  if (status != ARES_SUCCESS)
    {
       printf("%s\n", ares_strerror(status));
      if (!abuf)
    return;
    }
 
  /* Won't happen, but check anyway, for safety. */
  if (alen < HFIXEDSZ)
    return;
 
  /* Parse the answer header. */
  id = DNS_HEADER_QID(abuf);             /* query identification number */
  qr = DNS_HEADER_QR(abuf);              /* query response */
  opcode = DNS_HEADER_OPCODE(abuf);      /* opcode */
  aa = DNS_HEADER_AA(abuf);              /* authoritative answer */
  tc = DNS_HEADER_TC(abuf);              /* truncation */
  rd = DNS_HEADER_RD(abuf);              /* recursion desired */
  ra = DNS_HEADER_RA(abuf);              /* recursion available */
  rcode = DNS_HEADER_RCODE(abuf);        /* response code */
  qdcount = DNS_HEADER_QDCOUNT(abuf);    /* question count */
  ancount = DNS_HEADER_ANCOUNT(abuf);    /* answer record count */
  nscount = DNS_HEADER_NSCOUNT(abuf);    /* name server record count */
  arcount = DNS_HEADER_ARCOUNT(abuf);    /* additional record count */
 
  /* Display the answer header. */
  printf("id: %d\n", id);
  printf("flags: %s%s%s%s%s\n",
     qr ? "qr " : "",
     aa ? "aa " : "",
     tc ? "tc " : "",
     rd ? "rd " : "",
     ra ? "ra " : "");
  printf("opcode: %s\n", opcodes[opcode]);
  printf("rcode: %s\n", rcodes[rcode]);
 
  /* Display the questions. */
  printf("Questions:\n");
  aptr = abuf + HFIXEDSZ;
  for (i = 0; i < (int)qdcount; i++)
    {
      aptr = display_question(aptr, abuf, alen);
      if (aptr == NULL)
    return;
    }
 
  /* Display the answers. */
  printf("Answers:\n");
  for (i = 0; i < (int)ancount; i++)
    {
      aptr = display_rr(aptr, abuf, alen);
      if (aptr == NULL)
    return;
    }
 
  /* Display the NS records. */
  printf("NS records:\n");
  for (i = 0; i < (int)nscount; i++)
    {
      aptr = display_rr(aptr, abuf, alen);
      if (aptr == NULL)
    return;
    }
 
  /* Display the additional records. */
  printf("Additional records:\n");
  for (i = 0; i < (int)arcount; i++)
    {
      aptr = display_rr(aptr, abuf, alen);
      if (aptr == NULL)
    return;
    }
}
 
static const unsigned char *display_question(const unsigned char *aptr,
                         const unsigned char *abuf,
                         int alen)
{
  char *name;
  int type, dnsclass, status, len;
 
  /* Parse the question name. */
  status = ares_expand_name(aptr, abuf, alen, &name, &len);
  if (status != ARES_SUCCESS)
    return NULL;
  aptr += len;
 
  /* Make sure there's enough data after the name for the fixed part
   * of the question.
   */
  if (aptr + QFIXEDSZ > abuf + alen)
    {
      free(name);
      return NULL;
    }
 
  /* Parse the question type and class. */
  type = DNS_QUESTION_TYPE(aptr);
  dnsclass = DNS_QUESTION_CLASS(aptr);
  aptr += QFIXEDSZ;
 
  /* Display the question, in a format sort of similar to how we will
   * display RRs.
   */
  printf("\t%-15s.\t", name);
  if (dnsclass != C_IN)
    printf("\t%s", class_name(dnsclass));
  printf("\t%s\n", type_name(type));
  free(name);
  return aptr;
}
 
static const unsigned char *display_rr(const unsigned char *aptr,
                       const unsigned char *abuf, int alen)
{
  const unsigned char *p;
  char *name;
  int type, dnsclass, ttl, dlen, status, len;
  struct in_addr addr;
 
  /* Parse the RR name. */
  status = ares_expand_name(aptr, abuf, alen, &name, &len);
  if (status != ARES_SUCCESS)
    return NULL;
  aptr += len;
 
  /* Make sure there is enough data after the RR name for the fixed
   * part of the RR.
   */
  if (aptr + RRFIXEDSZ > abuf + alen)
    {
      free(name);
      return NULL;
    }
 
  /* Parse the fixed part of the RR, and advance to the RR data
   * field. */
  type = DNS_RR_TYPE(aptr);
  dnsclass = DNS_RR_CLASS(aptr);
  ttl = DNS_RR_TTL(aptr);
  dlen = DNS_RR_LEN(aptr);
  aptr += RRFIXEDSZ;
  if (aptr + dlen > abuf + alen)
    {
      free(name);
      return NULL;
    }
 
  /* Display the RR name, class, and type. */
  printf("\t%-15s.\t%d", name, ttl);
  if (dnsclass != C_IN)
    printf("\t%s", class_name(dnsclass));
  printf("\t%s", type_name(type));
  free(name);
 
  /* Display the RR data.  Don't touch aptr. */
  switch (type)
    {
    case T_CNAME:
    case T_MB:
    case T_MD:
    case T_MF:
    case T_MG:
    case T_MR:
    case T_NS:
    case T_PTR:
      /* For these types, the RR data is just a domain name. */
      status = ares_expand_name(aptr, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
    return NULL;
      printf("\t%s.", name);
      free(name);
      break;
 
    case T_HINFO:
      /* The RR data is two length-counted character strings. */
      p = aptr;
      len = *p;
      if (p + len + 1 > aptr + dlen)
    return NULL;
      printf("\t%.*s", len, p + 1);
      p += len + 1;
      len = *p;
      if (p + len + 1 > aptr + dlen)
    return NULL;
      printf("\t%.*s", len, p + 1);
      break;
 
    case T_MINFO:
      /* The RR data is two domain names. */
      p = aptr;
      status = ares_expand_name(p, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
    return NULL;
      printf("\t%s.", name);
      free(name);
      p += len;
      status = ares_expand_name(p, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
    return NULL;
      printf("\t%s.", name);
      free(name);
      break;
 
    case T_MX:
      /* The RR data is two bytes giving a preference ordering, and
       * then a domain name.
       */
      if (dlen < 2)
    return NULL;
      printf("\t%d", (aptr[0] << 8) | aptr[1]);
      status = ares_expand_name(aptr + 2, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
    return NULL;
      printf("\t%s.", name);
      free(name);
      break;
 
    case T_SOA:
      /* The RR data is two domain names and then five four-byte
       * numbers giving the serial number and some timeouts.
       */
      p = aptr;
      status = ares_expand_name(p, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
    return NULL;
      printf("\t%s.\n", name);
      free(name);
      p += len;
      status = ares_expand_name(p, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
    return NULL;
      printf("\t\t\t\t\t\t%s.\n", name);
      free(name);
      p += len;
      if (p + 20 > aptr + dlen)
    return NULL;
      printf("\t\t\t\t\t\t( %d %d %d %d %d )",
         (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3],
         (p[4] << 24) | (p[5] << 16) | (p[6] << 8) | p[7],
         (p[8] << 24) | (p[9] << 16) | (p[10] << 8) | p[11],
         (p[12] << 24) | (p[13] << 16) | (p[14] << 8) | p[15],
         (p[16] << 24) | (p[17] << 16) | (p[18] << 8) | p[19]);
      break;
 
    case T_TXT:
      /* The RR data is one or more length-counted character
       * strings. */
      p = aptr;
      while (p < aptr + dlen)
    {
      len = *p;
      if (p + len + 1 > aptr + dlen)
        return NULL;
      printf("\t%.*s", len, p + 1);
      p += len + 1;
    }
      break;
 
    case T_A:
      /* The RR data is a four-byte Internet address. */
      if (dlen != 4)
    return NULL;
      char addrBuf[INET_ADDRSTRLEN];
      memcpy(&addr, aptr, sizeof(struct in_addr));
      inet_ntop(AF_INET, &addr, addrBuf, sizeof(addrBuf));
      printf("\t%s", addrBuf);
      break;
 
    case T_WKS:
      /* Not implemented yet */
      break;
 
    case T_SRV:
      /* The RR data is three two-byte numbers representing the
       * priority, weight, and port, followed by a domain name.
       */
      
      printf("\t%d", DNS__16BIT(aptr));
      printf(" %d", DNS__16BIT(aptr + 2));
      printf(" %d", DNS__16BIT(aptr + 4));
      
      status = ares_expand_name(aptr + 6, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
        return NULL;
      printf("\t%s.", name);
      free(name);
      break;
      
    case T_NAPTR:
      /* The RR data is two two-byte numbers representing the
       * order and preference, followed by three character strings
       * representing flags, services, a regex, and a domain name.
       */
 
      printf("\t%d", DNS__16BIT(aptr));
      printf(" %d", DNS__16BIT(aptr + 2));
 
      p = aptr + 4;
      len = *p;
      if (p + len + 1 > aptr + dlen)
        return NULL;
      printf(" %.*s", len, p + 1);
      p += len + 1;
      len = *p;
      if (p + len + 1 > aptr + dlen)
        return NULL;
      printf(" %.*s", len, p + 1);
      p += len + 1;
      len = *p;
      if (p + len + 1 > aptr + dlen)
        return NULL;
      printf(" %.*s", len, p + 1);
      p += len + 1;
      status = ares_expand_name(p, abuf, alen, &name, &len);
      if (status != ARES_SUCCESS)
        return NULL;
      printf("\t%s.", name);
      free(name);
      break;
 
    default:
      printf("\t[Unknown RR; cannot parse]");
    }
  printf("\n");
 
  return aptr + dlen;
}
 
static const char *type_name(int type)
{
  int i;
 
  for (i = 0; i < ntypes; i++)
    {
      if (types[i].value == type)
    return types[i].name;
    }
  return "(unknown)";
}
 
static const char *class_name(int dnsclass)
{
  int i;
 
  for (i = 0; i < nclasses; i++)
    {
      if (classes[i].value == dnsclass)
    return classes[i].name;
    }
  return "(unknown)";
}
 
static void usage(void)
{
  fprintf(stderr, "usage: adig [-f flag] [-s server] [-c class] "
      "[-t type] [-p port] name ...\n");
  exit(1);
}