external/ibm-public/postfix/dist/src/dns/dns_rr_to_sa.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      dns_rr_to_sa 3
   6 /* SUMMARY
   7 /*      resource record to socket address
   8 /* SYNOPSIS
   9 /*      #include <dns.h>
  10 /*
  11 /*      int     dns_rr_to_sa(rr, port, sa, sa_length)
  12 /*      DNS_RR  *rr;
  13 /*      unsigned port;
  14 /*      struct sockaddr *sa;
  15 /*      SOCKADDR_SIZE *sa_length;
  16 /* DESCRIPTION
  17 /*      dns_rr_to_sa() converts the address in a DNS resource record into
  18 /*      a socket address of the corresponding type.
  19 /*
  20 /*      Arguments:
  21 /* .IP rr
  22 /*      DNS resource record pointer.
  23 /* .IP port
  24 /*      TCP or UDP port, network byte order.
  25 /* .IP sa
  26 /*      Socket address pointer.
  27 /* .IP sa_length
  28 /*      On input, the available socket address storage space.
  29 /*      On output, the amount of space actually used.
  30 /* DIAGNOSTICS
  31 /*      The result is non-zero in case of problems, with the
  32 /*      error type returned via the errno variable.
  33 /* LICENSE
  34 /* .ad
  35 /* .fi
  36 /*      The Secure Mailer license must be distributed with this software.
  37 /* AUTHOR(S)
  38 /*      Wietse Venema
  39 /*      IBM T.J. Watson Research
  40 /*      P.O. Box 704
  41 /*      Yorktown Heights, NY 10598, USA
  42 /*--*/
  43
  44 /* System libraries. */
  45
  46 #include <sys_defs.h>
  47 #include <errno.h>
  48
  49 /* Utility library. */
  50
  51 #include <msg.h>
  52
  53 /* DNS library. */
  54
  55 #include <dns.h>
  56
  57 /* dns_rr_to_sa - resource record to socket address */
  58
  59 int     dns_rr_to_sa(DNS_RR *rr, unsigned port, struct sockaddr * sa,
  60                              SOCKADDR_SIZE *sa_length)
  61 {
  62     SOCKADDR_SIZE sock_addr_len;
  63
  64     if (rr->type == T_A) {
  65         if (rr->data_len != sizeof(SOCK_ADDR_IN_ADDR(sa))) {
  66             errno = EINVAL;
  67             return (-1);
  68         } else if ((sock_addr_len = sizeof(*SOCK_ADDR_IN_PTR(sa))) > *sa_length) {
  69             errno = ENOSPC;
  70             return (-1);
  71         } else {
  72             memset((char *) SOCK_ADDR_IN_PTR(sa), 0, sock_addr_len);
  73             SOCK_ADDR_IN_FAMILY(sa) = AF_INET;
  74             SOCK_ADDR_IN_PORT(sa) = port;
  75             SOCK_ADDR_IN_ADDR(sa) = IN_ADDR(rr->data);
  76 #ifdef HAS_SA_LEN
  77             sa->sa_len = sock_addr_len;
  78 #endif
  79             *sa_length = sock_addr_len;
  80             return (0);
  81         }
  82 #ifdef HAS_IPV6
  83     } else if (rr->type == T_AAAA) {
  84         if (rr->data_len != sizeof(SOCK_ADDR_IN6_ADDR(sa))) {
  85             errno = EINVAL;
  86             return (-1);
  87         } else if ((sock_addr_len = sizeof(*SOCK_ADDR_IN6_PTR(sa))) > *sa_length) {
  88             errno = ENOSPC;
  89             return (-1);
  90         } else {
  91             memset((char *) SOCK_ADDR_IN6_PTR(sa), 0, sock_addr_len);
  92             SOCK_ADDR_IN6_FAMILY(sa) = AF_INET6;
  93             SOCK_ADDR_IN6_PORT(sa) = port;
  94             SOCK_ADDR_IN6_ADDR(sa) = IN6_ADDR(rr->data);
  95 #ifdef HAS_SA_LEN
  96             sa->sa_len = sock_addr_len;
  97 #endif
  98             *sa_length = sock_addr_len;
  99             return (0);
 100         }
 101 #endif
 102     } else {
 103         errno = EAFNOSUPPORT;
 104         return (-1);
 105     }
 106 }
 107
 108  /*
 109   * Stand-alone test program.
 110   */
 111 #ifdef TEST
 112 #include <stdlib.h>
 113
 114 #include <stringops.h>
 115 #include <vstream.h>
 116 #include <myaddrinfo.h>
 117
 118 static const char *myname;
 119
 120 static NORETURN usage(void)
 121 {
 122     msg_fatal("usage: %s dnsaddrtype hostname portnumber", myname);
 123 }
 124
 125 int     main(int argc, char **argv)
 126 {
 127     DNS_RR *rr;
 128     MAI_HOSTADDR_STR hostaddr;
 129     MAI_SERVPORT_STR portnum;
 130     struct sockaddr_storage ss;
 131     struct sockaddr *sa = (struct sockaddr *) & ss;
 132     SOCKADDR_SIZE sa_length = sizeof(ss);
 133     VSTRING *why;
 134     int     type;
 135     int     port;
 136
 137     myname = argv[0];
 138     if (argc < 4)
 139         usage();
 140     why = vstring_alloc(1);
 141
 142     while (*++argv) {
 143         if (argv[1] == 0 || argv[2] == 0)
 144             usage();
 145         if ((type = dns_type(argv[0])) == 0)
 146             usage();
 147         if (!alldig(argv[2]) || (port = atoi(argv[2])) > 65535)
 148             usage();
 149         if (dns_lookup(argv[1], type, 0, &rr, (VSTRING *) 0, why) != DNS_OK)
 150             msg_fatal("%s: %s", argv[1], vstring_str(why));
 151         sa_length = sizeof(ss);
 152         if (dns_rr_to_sa(rr, htons(port), sa, &sa_length) != 0)
 153             msg_fatal("dns_rr_to_sa: %m");
 154         SOCKADDR_TO_HOSTADDR(sa, sa_length, &hostaddr, &portnum, 0);
 155         vstream_printf("%s %s -> %s %s\n",
 156                        argv[1], argv[2], hostaddr.buf, portnum.buf);
 157         vstream_fflush(VSTREAM_OUT);
 158         argv += 2;
 159         dns_rr_free(rr);
 160     }
 161     vstring_free(why);
 162     return (0);
 163 }
 164
 165 #endif