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  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
  28  */
  29
  30 #include <sys/types.h>
  31 #include <netinet/in.h>
  32 #include <arpa/nameser.h>
  33 #include <resolv.h>
  34 #include <netdb.h>
  35 #include <limits.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <unistd.h>
  39 #include <ctype.h>
  40
  41 /*
  42  * Private resolver of target and type with arguments:
  43  * klooukp [ target [ RR_type ] ]
  44  *
  45  * Utitilizes DNS lookups to discover domain and realm information.  This CLI
  46  * is used primarily by kdcmgr(8) and kclient(8).
  47  */
  48
  49 int
  50 /* ARGSUSED */
  51 main(int argc, char **argv)
  52 {
  53         unsigned char answer[NS_MAXMSG], *ansp = NULL, *end, a, b, c, d;
  54         int len = 0, anslen, hostlen, nq, na, type, class;
  55         int ttl __unused, priority __unused, weight __unused, port, size;
  56         char name[NS_MAXDNAME], *cp, *typestr = NULL;
  57         char nbuf[INET6_ADDRSTRLEN];
  58         struct __res_state stat;
  59         int found = 0;
  60         int rr_type = T_A;
  61         HEADER *h;
  62
  63         type = T_A;
  64
  65         if (argc > 3)
  66                 exit(1);
  67
  68         if (argc == 1) {
  69                 if (gethostname(name, MAXHOSTNAMELEN) != 0)
  70                         exit(1);
  71         } else {
  72                 (void) strncpy(name, (char *)argv[1], NS_MAXDNAME);
  73                 if (argc == 3) {
  74                         typestr = argv[2];
  75
  76                         switch (*typestr) {
  77                         case 'A':
  78                                 rr_type = T_A;
  79                                 break;
  80                         case 'C':
  81                                 rr_type = T_CNAME;
  82                                 break;
  83                         case 'I':
  84                                 rr_type = T_A;
  85                                 break;
  86                         case 'P':
  87                                 rr_type = T_PTR;
  88                                 (void) sscanf(name, "%hhd.%hhd.%hhd.%hhd",
  89                                     &a, &b, &c, &d);
  90                                 (void) sprintf(name, "%d.%d.%d.%d.in-addr.arpa",
  91                                     d, c, b, a);
  92                                 break;
  93                         case 'S':
  94                                 rr_type = T_SRV;
  95                                 break;
  96                         default:
  97                                 exit(1);
  98                         }
  99                 }
 100         }
 101
 102         (void) memset(&stat, 0, sizeof (stat));
 103
 104         if (res_ninit(&stat) == -1)
 105                 exit(1);
 106
 107         anslen = sizeof (answer);
 108         len = res_nsearch(&stat, name, C_IN, rr_type, answer, anslen);
 109
 110         if (len < sizeof (HEADER)) {
 111                 res_ndestroy(&stat);
 112                 exit(1);
 113         }
 114
 115         ansp = answer;
 116         end = ansp + anslen;
 117
 118         /* LINTED */
 119         h = (HEADER *)answer;
 120         nq = ntohs(h->qdcount);
 121         na = ntohs(h->ancount);
 122         ansp += HFIXEDSZ;
 123
 124         if (nq != 1 || na < 1) {
 125                 res_ndestroy(&stat);
 126                 exit(1);
 127         }
 128
 129         hostlen = sizeof (name);
 130         len = dn_expand(answer, end, ansp, name, hostlen);
 131         if (len < 0) {
 132                 res_ndestroy(&stat);
 133                 exit(1);
 134         }
 135
 136         ansp += len + QFIXEDSZ;
 137
 138         if (ansp > end) {
 139                 res_ndestroy(&stat);
 140                 exit(1);
 141         }
 142
 143         while (na-- > 0 && ansp < end) {
 144
 145                 len = dn_expand(answer, end, ansp, name, hostlen);
 146
 147                 if (len < 0)
 148                         continue;
 149                 ansp += len;                    /* name */
 150                 NS_GET16(type, ansp);           /* type */
 151                 NS_GET16(class, ansp);          /* class */
 152                 NS_GET32(ttl, ansp);            /* ttl */
 153                 NS_GET16(size, ansp);           /* size */
 154
 155                 if ((ansp + size) > end) {
 156                         res_ndestroy(&stat);
 157                         exit(1);
 158                 }
 159                 if (type == T_SRV) {
 160                         NS_GET16(priority, ansp);
 161                         NS_GET16(weight, ansp);
 162                         NS_GET16(port, ansp);
 163                         len = dn_expand(answer, end, ansp, name, hostlen);
 164                         if (len < 0) {
 165                                 res_ndestroy(&stat);
 166                                 exit(1);
 167                         }
 168                         for (cp = name; *cp; cp++) {
 169                                 *cp = tolower(*cp);
 170                         }
 171                         (void) printf("%s %d\n", name, port);
 172                 } else if (typestr && *typestr == 'I') {
 173                         (void) inet_ntop(AF_INET, (void *)ansp, nbuf,
 174                             INET6_ADDRSTRLEN);
 175                         len = size;
 176                         (void) printf("%s\n", nbuf);
 177                 } else if (type == T_PTR) {
 178                         len = dn_expand(answer, end, ansp, name, hostlen);
 179                         if (len < 0) {
 180                                 res_ndestroy(&stat);
 181                                 exit(1);
 182                         }
 183                 }
 184                 ansp += len;
 185                 if (type == rr_type && class == C_IN) {
 186                         found = 1;
 187                         if (type != T_SRV && !(typestr && *typestr == 'I'))
 188                                 break;
 189                 }
 190         }
 191
 192         if (found != 1) {
 193                 res_ndestroy(&stat);
 194                 exit(1);
 195         }
 196
 197         for (cp = name; *cp; cp++) {
 198                 *cp = tolower(*cp);
 199         }
 200
 201         if (type != T_SRV && !(typestr && *typestr == 'I'))
 202                 (void) printf("%s\n", name);
 203
 204         res_ndestroy(&stat);
 205
 206         return (0);
 207 }