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 */
main(int argc,char ** argv)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 }
208