minix/lib/ip/res_mkquery.c
2009-11-09 10:26:00 +00:00

218 lines
5.9 KiB
C

/*
* Copyright (c) 1985 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement: ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution
* and in all advertising materials mentioning features or use of this
* software. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)res_mkquery.c 6.12 (Berkeley) 6/1/90";
#endif /* LIBC_SCCS and not lint */
#if _MINIX
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <net/hton.h>
#include <net/gen/in.h>
#include <net/gen/nameser.h>
#include <net/gen/resolv.h>
#define bzero(b,l) memset(b,0,l)
#define bcopy(s,d,l) memcpy(d,s,l)
#define putshort __putshort
#define putlong __putlong
#else
#include <stdio.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#endif
#ifdef __STDC__
#define _CONST const
#else
#define _CONST
#endif
/*
* Form all types of queries.
* Returns the size of the result or -1.
*/
res_mkquery(op, dname, class, type, data, datalen, newrr, buf, buflen)
int op; /* opcode of query */
_CONST char *dname; /* domain name */
int class, type; /* class and type of query */
_CONST char *data; /* resource record data */
int datalen; /* length of data */
_CONST struct rrec *newrr; /* new rr for modify or append */
char *buf; /* buffer to put query */
int buflen; /* size of buffer */
{
register dns_hdr_t *hp;
register char *cp;
register int n;
char *dnptrs[10], **dpp, **lastdnptr;
#ifdef DEBUG
if (_res.options & RES_DEBUG)
printf("res_mkquery(%d, %s, %d, %d)\n", op, dname, class, type);
#endif /* DEBUG */
/*
* Initialize header fields.
*/
if ((buf == NULL) || (buflen < sizeof(dns_hdr_t)))
return(-1);
bzero(buf, sizeof(dns_hdr_t));
hp = (dns_hdr_t *) buf;
hp->dh_id = htons(++_res.id);
hp->dh_flag1= 0;
hp->dh_flag2= 0;
hp->dh_flag1 |= (op << 3) & DHF_OPCODE;
hp->dh_flag2 |= ((_res.options & RES_PRIMARY) != 0 ? 1 : 0) << 6;
hp->dh_flag1 |= (_res.options & RES_RECURSE) != 0 ? 1 : 0;
hp->dh_flag2 |= NOERROR & DHF_RCODE;
cp = buf + sizeof(dns_hdr_t);
buflen -= sizeof(dns_hdr_t);
dpp = dnptrs;
*dpp++ = buf;
*dpp++ = NULL;
lastdnptr = dnptrs + sizeof(dnptrs)/sizeof(dnptrs[0]);
/*
* perform opcode specific processing
*/
switch (op) {
case QUERY:
if ((buflen -= QFIXEDSZ) < 0)
return(-1);
if ((n = dn_comp((u8_t *)dname, (u8_t *)cp, buflen,
(u8_t **)dnptrs, (u8_t **)lastdnptr)) < 0)
return (-1);
cp += n;
buflen -= n;
putshort(type, (u8_t *)cp);
cp += sizeof(u_short);
putshort(class, (u8_t *)cp);
cp += sizeof(u_short);
hp->dh_qdcount = HTONS(1);
if (op == QUERY || data == NULL)
break;
/*
* Make an additional record for completion domain.
*/
buflen -= RRFIXEDSZ;
if ((n = dn_comp((u8_t *)data, (u8_t *)cp, buflen,
(u8_t **)dnptrs, (u8_t **)lastdnptr)) < 0)
return (-1);
cp += n;
buflen -= n;
putshort(T_NULL, (u8_t *)cp);
cp += sizeof(u_short);
putshort(class, (u8_t *)cp);
cp += sizeof(u_short);
putlong(0, (u8_t *)cp);
cp += sizeof(u_long);
putshort(0, (u8_t *)cp);
cp += sizeof(u_short);
hp->dh_arcount = HTONS(1);
break;
case IQUERY:
/*
* Initialize answer section
*/
if (buflen < 1 + RRFIXEDSZ + datalen)
return (-1);
*cp++ = '\0'; /* no domain name */
putshort(type, (u8_t *)cp);
cp += sizeof(u_short);
putshort(class, (u8_t *)cp);
cp += sizeof(u_short);
putlong(0, (u8_t *)cp);
cp += sizeof(u_long);
putshort(datalen, (u8_t *)cp);
cp += sizeof(u_short);
if (datalen) {
bcopy(data, cp, datalen);
cp += datalen;
}
hp->dh_ancount = HTONS(1);
break;
#ifdef ALLOW_UPDATES
/*
* For UPDATEM/UPDATEMA, do UPDATED/UPDATEDA followed by UPDATEA
* (Record to be modified is followed by its replacement in msg.)
*/
case UPDATEM:
case UPDATEMA:
case UPDATED:
/*
* The res code for UPDATED and UPDATEDA is the same; user
* calls them differently: specifies data for UPDATED; server
* ignores data if specified for UPDATEDA.
*/
case UPDATEDA:
buflen -= RRFIXEDSZ + datalen;
if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
return (-1);
cp += n;
putshort(type, cp);
cp += sizeof(u_short);
putshort(class, cp);
cp += sizeof(u_short);
putlong(0, cp);
cp += sizeof(u_long);
putshort(datalen, cp);
cp += sizeof(u_short);
if (datalen) {
bcopy(data, cp, datalen);
cp += datalen;
}
if ( (op == UPDATED) || (op == UPDATEDA) ) {
hp->ancount = HTONS(0);
break;
}
/* Else UPDATEM/UPDATEMA, so drop into code for UPDATEA */
case UPDATEA: /* Add new resource record */
buflen -= RRFIXEDSZ + datalen;
if ((n = dn_comp(dname, cp, buflen, dnptrs, lastdnptr)) < 0)
return (-1);
cp += n;
putshort(newrr->r_type, cp);
cp += sizeof(u_short);
putshort(newrr->r_class, cp);
cp += sizeof(u_short);
putlong(0, cp);
cp += sizeof(u_long);
putshort(newrr->r_size, cp);
cp += sizeof(u_short);
if (newrr->r_size) {
bcopy(newrr->r_data, cp, newrr->r_size);
cp += newrr->r_size;
}
hp->ancount = HTONS(0);
break;
#endif /* ALLOW_UPDATES */
}
return (cp - buf);
}