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(1M) and kclient(1M).
  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, priority, weight, 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         if (argc > 3)
  64                 exit(1);
  65
  66         if (argc == 1) {
  67                 if (gethostname(name, MAXHOSTNAMELEN) != 0)
  68                         exit(1);
  69         } else {
  70                 (void) strncpy(name, (char *)argv[1], NS_MAXDNAME);
  71                 if (argc == 3) {
  72                         typestr = argv[2];
  73
  74                         switch (*typestr) {
  75                         case 'A':
  76                                 rr_type = T_A;
  77                                 break;
  78                         case 'C':
  79                                 rr_type = T_CNAME;
  80                                 break;
  81                         case 'I':
  82                                 rr_type = T_A;
  83                                 break;
  84                         case 'P':
  85                                 rr_type = T_PTR;
  86                                 (void) sscanf(name, "%hhd.%hhd.%hhd.%hhd",
  87                                     &a, &b, &c, &d);
  88                                 (void) sprintf(name, "%d.%d.%d.%d.in-addr.arpa",
  89                                     d, c, b, a);
  90                                 break;
  91                         case 'S':
  92                                 rr_type = T_SRV;
  93                                 break;
  94                         default:
  95                                 exit(1);
  96                         }
  97                 }
  98         }
  99
 100         (void) memset(&stat, 0, sizeof (stat));
 101
 102         if (res_ninit(&stat) == -1)
 103                 exit(1);
 104
 105         anslen = sizeof (answer);
 106         len = res_nsearch(&stat, name, C_IN, rr_type, answer, anslen);
 107
 108         if (len < sizeof (HEADER)) {
 109                 res_ndestroy(&stat);
 110                 exit(1);
 111         }
 112
 113         ansp = answer;
 114         end = ansp + anslen;
 115
 116         /* LINTED */
 117         h = (HEADER *)answer;
 118         nq = ntohs(h->qdcount);
 119         na = ntohs(h->ancount);
 120         ansp += HFIXEDSZ;
 121
 122         if (nq != 1 || na < 1) {
 123                 res_ndestroy(&stat);
 124                 exit(1);
 125         }
 126
 127         hostlen = sizeof (name);
 128         len = dn_expand(answer, end, ansp, name, hostlen);
 129         if (len < 0) {
 130                 res_ndestroy(&stat);
 131                 exit(1);
 132         }
 133
 134         ansp += len + QFIXEDSZ;
 135
 136         if (ansp > end) {
 137                 res_ndestroy(&stat);
 138                 exit(1);
 139         }
 140
 141         while (na-- > 0 && ansp < end) {
 142
 143                 len = dn_expand(answer, end, ansp, name, hostlen);
 144
 145                 if (len < 0)
 146                         continue;
 147                 ansp += len;                    /* name */
 148                 NS_GET16(type, ansp);           /* type */
 149                 NS_GET16(class, ansp);          /* class */
 150                 NS_GET32(ttl, ansp);            /* ttl */
 151                 NS_GET16(size, ansp);           /* size */
 152
 153                 if ((ansp + size) > end) {
 154                         res_ndestroy(&stat);
 155                         exit(1);
 156                 }
 157                 if (type == T_SRV) {
 158                         NS_GET16(priority, ansp);
 159                         NS_GET16(weight, ansp);
 160                         NS_GET16(port, ansp);
 161                         len = dn_expand(answer, end, ansp, name, hostlen);
 162                         if (len < 0) {
 163                                 res_ndestroy(&stat);
 164                                 exit(1);
 165                         }
 166                         for (cp = name; *cp; cp++) {
 167                                 *cp = tolower(*cp);
 168                         }
 169                         (void) printf("%s %d\n", name, port);
 170                 } else if (typestr && *typestr == 'I') {
 171                         (void) inet_ntop(AF_INET, (void *)ansp, nbuf,
 172                             INET6_ADDRSTRLEN);
 173                         len = size;
 174                         (void) printf("%s\n", nbuf);
 175                 } else if (type == T_PTR) {
 176                         len = dn_expand(answer, end, ansp, name, hostlen);
 177                         if (len < 0) {
 178                                 res_ndestroy(&stat);
 179                                 exit(1);
 180                         }
 181                 }
 182                 ansp += len;
 183                 if (type == rr_type && class == C_IN) {
 184                         found = 1;
 185                         if (type != T_SRV && !(typestr && *typestr == 'I'))
 186                                 break;
 187                 }
 188         }
 189
 190         if (found != 1) {
 191                 res_ndestroy(&stat);
 192                 exit(1);
 193         }
 194
 195         for (cp = name; *cp; cp++) {
 196                 *cp = tolower(*cp);
 197         }
 198
 199         if (type != T_SRV && !(typestr && *typestr == 'I'))
 200                 (void) printf("%s\n", name);
 201
 202         res_ndestroy(&stat);
 203
 204         return (0);
 205 }