1 | /*
|
---|
2 | * Copyright (c) 1985 Regents of the University of California.
|
---|
3 | * All rights reserved.
|
---|
4 | *
|
---|
5 | * Redistribution and use in source and binary forms are permitted
|
---|
6 | * provided that: (1) source distributions retain this entire copyright
|
---|
7 | * notice and comment, and (2) distributions including binaries display
|
---|
8 | * the following acknowledgement: ``This product includes software
|
---|
9 | * developed by the University of California, Berkeley and its contributors''
|
---|
10 | * in the documentation or other materials provided with the distribution
|
---|
11 | * and in all advertising materials mentioning features or use of this
|
---|
12 | * software. Neither the name of the University nor the names of its
|
---|
13 | * contributors may be used to endorse or promote products derived
|
---|
14 | * from this software without specific prior written permission.
|
---|
15 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
---|
16 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
---|
17 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
---|
18 | */
|
---|
19 |
|
---|
20 | #if defined(LIBC_SCCS) && !defined(lint)
|
---|
21 | static char sccsid[] = "@(#)res_mkquery.c 6.12 (Berkeley) 6/1/90";
|
---|
22 | #endif /* LIBC_SCCS and not lint */
|
---|
23 |
|
---|
24 | #if _MINIX
|
---|
25 | #include <sys/types.h>
|
---|
26 | #include <stdio.h>
|
---|
27 | #include <stdlib.h>
|
---|
28 | #include <string.h>
|
---|
29 |
|
---|
30 | #include <net/hton.h>
|
---|
31 | #include <net/gen/in.h>
|
---|
32 | #include <net/gen/nameser.h>
|
---|
33 | #include <net/gen/resolv.h>
|
---|
34 |
|
---|
35 | #define bzero(b,l) memset(b,0,l)
|
---|
36 | #define bcopy(s,d,l) memcpy(d,s,l)
|
---|
37 |
|
---|
38 | #define putshort __putshort
|
---|
39 | #define putlong __putlong
|
---|
40 | #else
|
---|
41 | #include <stdio.h>
|
---|
42 | #include <sys/types.h>
|
---|
43 | #include <netinet/in.h>
|
---|
44 | #include <arpa/nameser.h>
|
---|
45 | #include <resolv.h>
|
---|
46 | #endif
|
---|
47 |
|
---|
48 | #ifdef __STDC__
|
---|
49 | #define _CONST const
|
---|
50 | #else
|
---|
51 | #define _CONST
|
---|
52 | #endif
|
---|
53 |
|
---|
54 | /*
|
---|
55 | * Form all types of queries.
|
---|
56 | * Returns the size of the result or -1.
|
---|
57 | */
|
---|
58 | res_mkquery(op, dname, class, type, data, datalen, newrr, buf, buflen)
|
---|
59 | int op; /* opcode of query */
|
---|
60 | _CONST char *dname; /* domain name */
|
---|
61 | int class, type; /* class and type of query */
|
---|
62 | _CONST char *data; /* resource record data */
|
---|
63 | int datalen; /* length of data */
|
---|
64 | _CONST struct rrec *newrr; /* new rr for modify or append */
|
---|
65 | char *buf; /* buffer to put query */
|
---|
66 | int buflen; /* size of buffer */
|
---|
67 | {
|
---|
68 | register dns_hdr_t *hp;
|
---|
69 | register char *cp;
|
---|
70 | register int n;
|
---|
71 | char *dnptrs[10], **dpp, **lastdnptr;
|
---|
72 |
|
---|
73 | #ifdef DEBUG
|
---|
74 | if (_res.options & RES_DEBUG)
|
---|
75 | printf("res_mkquery(%d, %s, %d, %d)\n", op, dname, class, type);
|
---|
76 | #endif /* DEBUG */
|
---|
77 | /*
|
---|
78 | * Initialize header fields.
|
---|
79 | */
|
---|
80 | if ((buf == NULL) || (buflen < sizeof(dns_hdr_t)))
|
---|
81 | return(-1);
|
---|
82 | bzero(buf, sizeof(dns_hdr_t));
|
---|
83 | hp = (dns_hdr_t *) buf;
|
---|
84 | hp->dh_id = htons(++_res.id);
|
---|
85 | hp->dh_flag1= 0;
|
---|
86 | hp->dh_flag2= 0;
|
---|
87 | hp->dh_flag1 |= (op << 3) & DHF_OPCODE;
|
---|
88 | hp->dh_flag2 |= ((_res.options & RES_PRIMARY) != 0 ? 1 : 0) << 6;
|
---|
89 | hp->dh_flag1 |= (_res.options & RES_RECURSE) != 0 ? 1 : 0;
|
---|
90 | hp->dh_flag2 |= NOERROR & DHF_RCODE;
|
---|
91 | cp = buf + sizeof(dns_hdr_t);
|
---|
92 | buflen -= sizeof(dns_hdr_t);
|
---|
93 | dpp = dnptrs;
|
---|
94 | *dpp++ = buf;
|
---|
95 | *dpp++ = NULL;
|
---|
96 | lastdnptr = dnptrs + sizeof(dnptrs)/sizeof(dnptrs[0]);
|
---|
97 | /*
|
---|
98 | * perform opcode specific processing
|
---|
99 | */
|
---|
100 | switch (op) {
|
---|
101 | case QUERY:
|
---|
102 | if ((buflen -= QFIXEDSZ) < 0)
|
---|
103 | return(-1);
|
---|
104 | if ((n = dn_comp((u8_t *)dname, (u8_t *)cp, buflen,
|
---|
105 | (u8_t **)dnptrs, (u8_t **)lastdnptr)) < 0)
|
---|
106 | return (-1);
|
---|
107 | cp += n;
|
---|
108 | buflen -= n;
|
---|
109 | putshort(type, (u8_t *)cp);
|
---|
110 | cp += sizeof(u_short);
|
---|
111 | putshort(class, (u8_t *)cp);
|
---|
112 | cp += sizeof(u_short);
|
---|
113 | hp->dh_qdcount = HTONS(1);
|
---|
114 | if (op == QUERY || data == NULL)
|
---|
115 | break;
|
---|
116 | /*
|
---|
117 | * Make an additional record for completion domain.
|
---|
118 | */
|
---|
119 | buflen -= RRFIXEDSZ;
|
---|
120 | if ((n = dn_comp((u8_t *)data, (u8_t *)cp, buflen,
|
---|
121 | (u8_t **)dnptrs, (u8_t **)lastdnptr)) < 0)
|
---|
122 | return (-1);
|
---|
123 | cp += n;
|
---|
124 | buflen -= n;
|
---|
125 | putshort(T_NULL, (u8_t *)cp);
|
---|
126 | cp += sizeof(u_short);
|
---|
127 | putshort(class, (u8_t *)cp);
|
---|
128 | cp += sizeof(u_short);
|
---|
129 | putlong(0, (u8_t *)cp);
|
---|
130 | cp += sizeof(u_long);
|
---|
131 | putshort(0, (u8_t *)cp);
|
---|
132 | cp += sizeof(u_short);
|
---|
133 | hp->dh_arcount = HTONS(1);
|
---|
134 | break;
|
---|
135 |
|
---|
136 | case IQUERY:
|
---|
137 | /*
|
---|
138 | * Initialize answer section
|
---|
139 | */
|
---|
140 | if (buflen < 1 + RRFIXEDSZ + datalen)
|
---|
141 | return (-1);
|
---|
142 | *cp++ = '\0'; /* no domain name */
|
---|
143 | putshort(type, (u8_t *)cp);
|
---|
144 | cp += sizeof(u_short);
|
---|
145 | putshort(class, (u8_t *)cp);
|
---|
146 | cp += sizeof(u_short);
|
---|
147 | putlong(0, (u8_t *)cp);
|
---|
148 | cp += sizeof(u_long);
|
---|
149 | putshort(datalen, (u8_t *)cp);
|
---|
150 | cp += sizeof(u_short);
|
---|
151 | if (datalen) {
|
---|
152 | bcopy(data, cp, datalen);
|
---|
153 | cp += datalen;
|
---|
154 | }
|
---|
155 | hp->dh_ancount = HTONS(1);
|
---|
156 | break;
|
---|
157 |
|
---|
158 | #ifdef ALLOW_UPDATES
|
---|
159 | /*
|
---|
160 | * For UPDATEM/UPDATEMA, do UPDATED/UPDATEDA followed by UPDATEA
|
---|
161 | * (Record to be modified is followed by its replacement in msg.)
|
---|
162 | */
|
---|
163 | case UPDATEM:
|
---|
164 | case UPDATEMA:
|
---|
165 |
|
---|
166 | case UPDATED:
|
---|
167 | /*
|
---|
168 | * The res code for UPDATED and UPDATEDA is the same; user
|
---|
169 | * calls them differently: specifies data for UPDATED; server
|
---|
170 | * ignores data if specified for UPDATEDA.
|
---|
171 | */
|
---|
172 | case UPDATEDA:
|
---|
173 | buflen -= RRFIXEDSZ + datalen;
|
---|
174 | if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
|
---|
175 | return (-1);
|
---|
176 | cp += n;
|
---|
177 | putshort(type, cp);
|
---|
178 | cp += sizeof(u_short);
|
---|
179 | putshort(class, cp);
|
---|
180 | cp += sizeof(u_short);
|
---|
181 | putlong(0, cp);
|
---|
182 | cp += sizeof(u_long);
|
---|
183 | putshort(datalen, cp);
|
---|
184 | cp += sizeof(u_short);
|
---|
185 | if (datalen) {
|
---|
186 | bcopy(data, cp, datalen);
|
---|
187 | cp += datalen;
|
---|
188 | }
|
---|
189 | if ( (op == UPDATED) || (op == UPDATEDA) ) {
|
---|
190 | hp->ancount = HTONS(0);
|
---|
191 | break;
|
---|
192 | }
|
---|
193 | /* Else UPDATEM/UPDATEMA, so drop into code for UPDATEA */
|
---|
194 |
|
---|
195 | case UPDATEA: /* Add new resource record */
|
---|
196 | buflen -= RRFIXEDSZ + datalen;
|
---|
197 | if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
|
---|
198 | return (-1);
|
---|
199 | cp += n;
|
---|
200 | putshort(newrr->r_type, cp);
|
---|
201 | cp += sizeof(u_short);
|
---|
202 | putshort(newrr->r_class, cp);
|
---|
203 | cp += sizeof(u_short);
|
---|
204 | putlong(0, cp);
|
---|
205 | cp += sizeof(u_long);
|
---|
206 | putshort(newrr->r_size, cp);
|
---|
207 | cp += sizeof(u_short);
|
---|
208 | if (newrr->r_size) {
|
---|
209 | bcopy(newrr->r_data, cp, newrr->r_size);
|
---|
210 | cp += newrr->r_size;
|
---|
211 | }
|
---|
212 | hp->ancount = HTONS(0);
|
---|
213 | break;
|
---|
214 |
|
---|
215 | #endif /* ALLOW_UPDATES */
|
---|
216 | }
|
---|
217 | return (cp - buf);
|
---|
218 | }
|
---|