usr/src/cmd/krb5/kadmin/kdcmgr/klookup.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/types.h>
  30 #include <netinet/in.h>
  31 #include <arpa/nameser.h>
  32 #include <resolv.h>
  33 #include <netdb.h>
  34 #include <limits.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <unistd.h>
  38 #include <ctype.h>
  39
  40 /*
  41  * Private resolver of target and type with arguments:
  42  * klooukp [ target [ RR_type ] ]
  43  *
  44  * Utitilizes DNS lookups to discover domain and realm information.  This CLI
  45  * is used primarily by kdcmgr(1M) and kclient(1M).
  46  */
  47
  48 int
  49 /* ARGSUSED */
  50 main(int argc, char **argv)
  51 {
  52         unsigned char answer[NS_MAXMSG], *ansp = NULL, *end, a, b, c, d;
  53         int len = 0, anslen, hostlen, nq, na, type, class;
  54         int ttl, priority, weight, port, size;
  55         char name[NS_MAXDNAME], *cp, *typestr = NULL;
  56         char nbuf[INET6_ADDRSTRLEN];
  57         struct __res_state stat;
  58         int found = 0;
  59         int rr_type = T_A;
  60         HEADER *h;
  61
  62         if (argc > 3)
  63                 exit(1);
  64
  65         if (argc == 1) {
  66                 if (gethostname(name, MAXHOSTNAMELEN) != 0)
  67                         exit(1);
  68         } else {
  69                 (void) strncpy(name, (char *)argv[1], NS_MAXDNAME);
  70                 if (argc == 3) {
  71                         typestr = argv[2];
  72
  73                         switch (*typestr) {
  74                         case 'A':
  75                                 rr_type = T_A;
  76                                 break;
  77                         case 'C':
  78                                 rr_type = T_CNAME;
  79                                 break;
  80                         case 'I':
  81                                 rr_type = T_A;
  82                                 break;
  83                         case 'P':
  84                                 rr_type = T_PTR;
  85                                 (void) sscanf(name, "%d.%d.%d.%d",
  86                                     &a, &b, &c, &d);
  87                                 (void) sprintf(name, "%d.%d.%d.%d.in-addr.arpa",
  88                                     d, c, b, a);
  89                                 break;
  90                         case 'S':
  91                                 rr_type = T_SRV;
  92                                 break;
  93                         default:
  94                                 exit(1);
  95                         }
  96                 }
  97         }
  98
  99         (void) memset(&stat, 0, sizeof (stat));
 100
 101         if (res_ninit(&stat) == -1)
 102                 exit(1);
 103
 104         anslen = sizeof (answer);
 105         len = res_nsearch(&stat, name, C_IN, rr_type, answer, anslen);
 106
 107         if (len < sizeof (HEADER)) {
 108                 res_ndestroy(&stat);
 109                 exit(1);
 110         }
 111
 112         ansp = answer;
 113         end = ansp + anslen;
 114
 115         /* LINTED */
 116         h = (HEADER *)answer;
 117         nq = ntohs(h->qdcount);
 118         na = ntohs(h->ancount);
 119         ansp += HFIXEDSZ;
 120
 121         if (nq != 1 || na < 1) {
 122                 res_ndestroy(&stat);
 123                 exit(1);
 124         }
 125
 126         hostlen = sizeof (name);
 127         len = dn_expand(answer, end, ansp, name, hostlen);
 128         if (len < 0) {
 129                 res_ndestroy(&stat);
 130                 exit(1);
 131         }
 132
 133         ansp += len + QFIXEDSZ;
 134
 135         if (ansp > end) {
 136                 res_ndestroy(&stat);
 137                 exit(1);
 138         }
 139
 140         while (na-- > 0 && ansp < end) {
 141
 142                 len = dn_expand(answer, end, ansp, name, hostlen);
 143
 144                 if (len < 0)
 145                         continue;
 146                 ansp += len;                    /* name */
 147                 NS_GET16(type, ansp);           /* type */
 148                 NS_GET16(class, ansp);          /* class */
 149                 NS_GET32(ttl, ansp);            /* ttl */
 150                 NS_GET16(size, ansp);           /* size */
 151
 152                 if ((ansp + size) > end) {
 153                         res_ndestroy(&stat);
 154                         exit(1);
 155                 }
 156                 if (type == T_SRV) {
 157                         NS_GET16(priority, ansp);
 158                         NS_GET16(weight, ansp);
 159                         NS_GET16(port, ansp);
 160                         len = dn_expand(answer, end, ansp, name, hostlen);
 161                         if (len < 0) {
 162                                 res_ndestroy(&stat);
 163                                 exit(1);
 164                         }
 165                         for (cp = name; *cp; cp++) {
 166                                 *cp = tolower(*cp);
 167                         }
 168                         (void) printf("%s %d\n", name, port);
 169                 } else if (typestr && *typestr == 'I') {
 170                         (void) inet_ntop(AF_INET, (void *)ansp, nbuf,
 171                             INET6_ADDRSTRLEN);
 172                         len = size;
 173                         (void) printf("%s\n", nbuf);
 174                 } else if (type == T_PTR) {
 175                         len = dn_expand(answer, end, ansp, name, hostlen);
 176                         if (len < 0) {
 177                                 res_ndestroy(&stat);
 178                                 exit(1);
 179                         }
 180                 }
 181                 ansp += len;
 182                 if (type == rr_type && class == C_IN) {
 183                         found = 1;
 184                         if (type != T_SRV && !(typestr && *typestr == 'I'))
 185                                 break;
 186                 }
 187         }
 188
 189         if (found != 1) {
 190                 res_ndestroy(&stat);
 191                 exit(1);
 192         }
 193
 194         for (cp = name; *cp; cp++) {
 195                 *cp = tolower(*cp);
 196         }
 197
 198         if (type != T_SRV && !(typestr && *typestr == 'I'))
 199                 (void) printf("%s\n", name);
 200
 201         res_ndestroy(&stat);
 202
 203         return (0);
 204 }