1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
3*0Sstevel@tonic-gate * Use is subject to license terms.
4*0Sstevel@tonic-gate */
5*0Sstevel@tonic-gate
6*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI"
7*0Sstevel@tonic-gate
8*0Sstevel@tonic-gate #ifdef LDAP_DNS
9*0Sstevel@tonic-gate /*
10*0Sstevel@tonic-gate * Copyright (c) 1995 Regents of the University of Michigan.
11*0Sstevel@tonic-gate * All rights reserved.
12*0Sstevel@tonic-gate *
13*0Sstevel@tonic-gate * getdxbyname - retrieve DX records from the DNS (from TXT records for now)
14*0Sstevel@tonic-gate */
15*0Sstevel@tonic-gate #include <stdio.h>
16*0Sstevel@tonic-gate #include <string.h>
17*0Sstevel@tonic-gate #include <ctype.h>
18*0Sstevel@tonic-gate
19*0Sstevel@tonic-gate #ifdef MACOS
20*0Sstevel@tonic-gate #include <stdlib.h>
21*0Sstevel@tonic-gate #include "macos.h"
22*0Sstevel@tonic-gate #endif /* MACOS */
23*0Sstevel@tonic-gate
24*0Sstevel@tonic-gate #if !defined(MACOS) && !defined(DOS) && !defined( _WIN32 )
25*0Sstevel@tonic-gate #include <sys/types.h>
26*0Sstevel@tonic-gate #include <netinet/in.h>
27*0Sstevel@tonic-gate #include <arpa/nameser.h>
28*0Sstevel@tonic-gate #include <sys/time.h>
29*0Sstevel@tonic-gate #include <sys/types.h>
30*0Sstevel@tonic-gate #include <sys/socket.h>
31*0Sstevel@tonic-gate #include <netdb.h>
32*0Sstevel@tonic-gate #include <resolv.h>
33*0Sstevel@tonic-gate #endif
34*0Sstevel@tonic-gate #include "lber.h"
35*0Sstevel@tonic-gate #include "ldap.h"
36*0Sstevel@tonic-gate #include "ldap-private.h"
37*0Sstevel@tonic-gate #include "ldap-int.h"
38*0Sstevel@tonic-gate
39*0Sstevel@tonic-gate #if defined( DOS ) || defined( _WIN32 )
40*0Sstevel@tonic-gate #include "msdos.h"
41*0Sstevel@tonic-gate #endif /* DOS */
42*0Sstevel@tonic-gate
43*0Sstevel@tonic-gate
44*0Sstevel@tonic-gate #ifdef NEEDPROTOS
45*0Sstevel@tonic-gate static char ** decode_answer( unsigned char *answer, int len );
46*0Sstevel@tonic-gate #else /* NEEDPROTOS */
47*0Sstevel@tonic-gate static char **decode_answer();
48*0Sstevel@tonic-gate #endif /* NEEDPROTOS */
49*0Sstevel@tonic-gate
50*0Sstevel@tonic-gate extern int h_errno;
51*0Sstevel@tonic-gate extern char *h_errlist[];
52*0Sstevel@tonic-gate
53*0Sstevel@tonic-gate
54*0Sstevel@tonic-gate #define MAX_TO_SORT 32
55*0Sstevel@tonic-gate
56*0Sstevel@tonic-gate
57*0Sstevel@tonic-gate /*
58*0Sstevel@tonic-gate * getdxbyname - lookup DNS DX records for domain and return an ordered
59*0Sstevel@tonic-gate * array.
60*0Sstevel@tonic-gate */
61*0Sstevel@tonic-gate char **
getdxbyname(char * domain)62*0Sstevel@tonic-gate getdxbyname( char *domain )
63*0Sstevel@tonic-gate {
64*0Sstevel@tonic-gate unsigned char buf[ PACKETSZ ];
65*0Sstevel@tonic-gate char **dxs;
66*0Sstevel@tonic-gate int rc;
67*0Sstevel@tonic-gate
68*0Sstevel@tonic-gate Debug( LDAP_DEBUG_TRACE, "getdxbyname( %s )\n", domain, 0, 0 );
69*0Sstevel@tonic-gate
70*0Sstevel@tonic-gate memset( buf, 0, sizeof( buf ));
71*0Sstevel@tonic-gate
72*0Sstevel@tonic-gate if (( rc = res_search( domain, C_IN, T_TXT, buf, sizeof( buf ))) < 0
73*0Sstevel@tonic-gate || ( dxs = decode_answer( buf, rc )) == NULL ) {
74*0Sstevel@tonic-gate /*
75*0Sstevel@tonic-gate * punt: return list conisting of the original domain name only
76*0Sstevel@tonic-gate */
77*0Sstevel@tonic-gate if (( dxs = (char **)malloc( 2 * sizeof( char * ))) == NULL ||
78*0Sstevel@tonic-gate ( dxs[ 0 ] = strdup( domain )) == NULL ) {
79*0Sstevel@tonic-gate if ( dxs != NULL ) {
80*0Sstevel@tonic-gate free( dxs );
81*0Sstevel@tonic-gate }
82*0Sstevel@tonic-gate dxs = NULL;
83*0Sstevel@tonic-gate } else {
84*0Sstevel@tonic-gate dxs[ 1 ] = NULL;
85*0Sstevel@tonic-gate }
86*0Sstevel@tonic-gate }
87*0Sstevel@tonic-gate
88*0Sstevel@tonic-gate return( dxs );
89*0Sstevel@tonic-gate }
90*0Sstevel@tonic-gate
91*0Sstevel@tonic-gate
92*0Sstevel@tonic-gate static char **
decode_answer(unsigned char * answer,int len)93*0Sstevel@tonic-gate decode_answer( unsigned char *answer, int len )
94*0Sstevel@tonic-gate {
95*0Sstevel@tonic-gate HEADER *hp;
96*0Sstevel@tonic-gate char buf[ 256 ], **dxs;
97*0Sstevel@tonic-gate unsigned char *eom, *p;
98*0Sstevel@tonic-gate int ancount, err, rc, type, class, dx_count, rr_len;
99*0Sstevel@tonic-gate int dx_pref[ MAX_TO_SORT ];
100*0Sstevel@tonic-gate
101*0Sstevel@tonic-gate int _getshort( unsigned char * );
102*0Sstevel@tonic-gate #ifdef LDAP_DEBUG
103*0Sstevel@tonic-gate if ( ldap_debug & LDAP_DEBUG_PACKETS ) {
104*0Sstevel@tonic-gate /* __p_query( answer ); */
105*0Sstevel@tonic-gate }
106*0Sstevel@tonic-gate #endif /* LDAP_DEBUG */
107*0Sstevel@tonic-gate
108*0Sstevel@tonic-gate dxs = NULL;
109*0Sstevel@tonic-gate hp = (HEADER *)answer;
110*0Sstevel@tonic-gate eom = answer + len;
111*0Sstevel@tonic-gate
112*0Sstevel@tonic-gate if ( ntohs( hp->qdcount ) != 1 ) {
113*0Sstevel@tonic-gate h_errno = NO_RECOVERY;
114*0Sstevel@tonic-gate return( NULL );
115*0Sstevel@tonic-gate }
116*0Sstevel@tonic-gate
117*0Sstevel@tonic-gate ancount = ntohs( hp->ancount );
118*0Sstevel@tonic-gate if ( ancount < 1 ) {
119*0Sstevel@tonic-gate h_errno = NO_DATA;
120*0Sstevel@tonic-gate return( NULL );
121*0Sstevel@tonic-gate }
122*0Sstevel@tonic-gate
123*0Sstevel@tonic-gate /*
124*0Sstevel@tonic-gate * skip over the query
125*0Sstevel@tonic-gate */
126*0Sstevel@tonic-gate p = answer + HFIXEDSZ;
127*0Sstevel@tonic-gate if (( rc = dn_expand( answer, eom, p, buf, sizeof( buf ))) < 0 ) {
128*0Sstevel@tonic-gate h_errno = NO_RECOVERY;
129*0Sstevel@tonic-gate return( NULL );
130*0Sstevel@tonic-gate }
131*0Sstevel@tonic-gate p += ( rc + QFIXEDSZ );
132*0Sstevel@tonic-gate
133*0Sstevel@tonic-gate /*
134*0Sstevel@tonic-gate * pull out the answers we are interested in
135*0Sstevel@tonic-gate */
136*0Sstevel@tonic-gate err = dx_count = 0;
137*0Sstevel@tonic-gate while ( ancount > 0 && err == 0 && p < eom ) {
138*0Sstevel@tonic-gate if (( rc = dn_expand( answer, eom, p, buf, sizeof( buf ))) < 0 ) {
139*0Sstevel@tonic-gate err = NO_RECOVERY;
140*0Sstevel@tonic-gate continue;
141*0Sstevel@tonic-gate }
142*0Sstevel@tonic-gate p += rc; /* skip over name */
143*0Sstevel@tonic-gate type = _getshort( p );
144*0Sstevel@tonic-gate p += INT16SZ;
145*0Sstevel@tonic-gate class = _getshort( p );
146*0Sstevel@tonic-gate p += INT16SZ;
147*0Sstevel@tonic-gate p += INT32SZ; /* skip over TTL */
148*0Sstevel@tonic-gate rr_len = _getshort( p );
149*0Sstevel@tonic-gate p += INT16SZ;
150*0Sstevel@tonic-gate if ( class == C_IN && type == T_TXT ) {
151*0Sstevel@tonic-gate int i, n, pref, txt_len;
152*0Sstevel@tonic-gate char *q, *r;
153*0Sstevel@tonic-gate
154*0Sstevel@tonic-gate q = (char *)p;
155*0Sstevel@tonic-gate while ( q < (char *)p + rr_len && err == 0 ) {
156*0Sstevel@tonic-gate if ( *q >= 3 && strncasecmp( q + 1, "dx:", 3 ) == 0 ) {
157*0Sstevel@tonic-gate txt_len = *q - 3;
158*0Sstevel@tonic-gate r = q + 4;
159*0Sstevel@tonic-gate while ( isspace( *r )) {
160*0Sstevel@tonic-gate ++r;
161*0Sstevel@tonic-gate --txt_len;
162*0Sstevel@tonic-gate }
163*0Sstevel@tonic-gate pref = 0;
164*0Sstevel@tonic-gate while ( isdigit( *r )) {
165*0Sstevel@tonic-gate pref *= 10;
166*0Sstevel@tonic-gate pref += ( *r - '0' );
167*0Sstevel@tonic-gate ++r;
168*0Sstevel@tonic-gate --txt_len;
169*0Sstevel@tonic-gate }
170*0Sstevel@tonic-gate if ( dx_count < MAX_TO_SORT - 1 ) {
171*0Sstevel@tonic-gate dx_pref[ dx_count ] = pref;
172*0Sstevel@tonic-gate }
173*0Sstevel@tonic-gate while ( isspace( *r )) {
174*0Sstevel@tonic-gate ++r;
175*0Sstevel@tonic-gate --txt_len;
176*0Sstevel@tonic-gate }
177*0Sstevel@tonic-gate if ( dx_count == 0 ) {
178*0Sstevel@tonic-gate dxs = (char **)malloc( 2 * sizeof( char * ));
179*0Sstevel@tonic-gate } else {
180*0Sstevel@tonic-gate dxs = (char **)realloc( dxs,
181*0Sstevel@tonic-gate ( dx_count + 2 ) * sizeof( char * ));
182*0Sstevel@tonic-gate }
183*0Sstevel@tonic-gate if ( dxs == NULL || ( dxs[ dx_count ] =
184*0Sstevel@tonic-gate (char *)calloc( 1, txt_len + 1 )) == NULL ) {
185*0Sstevel@tonic-gate err = NO_RECOVERY;
186*0Sstevel@tonic-gate continue;
187*0Sstevel@tonic-gate }
188*0Sstevel@tonic-gate memcpy( dxs[ dx_count ], r, txt_len );
189*0Sstevel@tonic-gate dxs[ ++dx_count ] = NULL;
190*0Sstevel@tonic-gate }
191*0Sstevel@tonic-gate q += ( *q + 1 ); /* move past last TXT record */
192*0Sstevel@tonic-gate }
193*0Sstevel@tonic-gate }
194*0Sstevel@tonic-gate p += rr_len;
195*0Sstevel@tonic-gate }
196*0Sstevel@tonic-gate
197*0Sstevel@tonic-gate if ( err == 0 ) {
198*0Sstevel@tonic-gate if ( dx_count == 0 ) {
199*0Sstevel@tonic-gate err = NO_DATA;
200*0Sstevel@tonic-gate } else {
201*0Sstevel@tonic-gate /*
202*0Sstevel@tonic-gate * sort records based on associated preference value
203*0Sstevel@tonic-gate */
204*0Sstevel@tonic-gate int i, j, sort_count, tmp_pref;
205*0Sstevel@tonic-gate char *tmp_dx;
206*0Sstevel@tonic-gate
207*0Sstevel@tonic-gate sort_count = ( dx_count < MAX_TO_SORT ) ? dx_count : MAX_TO_SORT;
208*0Sstevel@tonic-gate for ( i = 0; i < sort_count; ++i ) {
209*0Sstevel@tonic-gate for ( j = i + 1; j < sort_count; ++j ) {
210*0Sstevel@tonic-gate if ( dx_pref[ i ] > dx_pref[ j ] ) {
211*0Sstevel@tonic-gate tmp_pref = dx_pref[ i ];
212*0Sstevel@tonic-gate dx_pref[ i ] = dx_pref[ j ];
213*0Sstevel@tonic-gate dx_pref[ j ] = tmp_pref;
214*0Sstevel@tonic-gate tmp_dx = dxs[ i ];
215*0Sstevel@tonic-gate dxs[ i ] = dxs[ j ];
216*0Sstevel@tonic-gate dxs[ j ] = tmp_dx;
217*0Sstevel@tonic-gate }
218*0Sstevel@tonic-gate }
219*0Sstevel@tonic-gate }
220*0Sstevel@tonic-gate }
221*0Sstevel@tonic-gate }
222*0Sstevel@tonic-gate
223*0Sstevel@tonic-gate h_errno = err;
224*0Sstevel@tonic-gate return( dxs );
225*0Sstevel@tonic-gate }
226*0Sstevel@tonic-gate
227*0Sstevel@tonic-gate #endif /* LDAP_DNS */
228