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-rw-r--r--source3/libads/dns.c215
1 files changed, 199 insertions, 16 deletions
diff --git a/source3/libads/dns.c b/source3/libads/dns.c
index 321b435527..570f9583f0 100644
--- a/source3/libads/dns.c
+++ b/source3/libads/dns.c
@@ -46,6 +46,7 @@
# define T_A ns_t_a
#endif
# define T_SRV ns_t_srv
+# define T_NS ns_t_ns
#else
# ifdef HFIXEDSZ
# define NS_HFIXEDSZ HFIXEDSZ
@@ -197,6 +198,46 @@ static BOOL ads_dns_parse_rr_srv( TALLOC_CTX *ctx, uint8 *start, uint8 *end,
return True;
}
+/*********************************************************************
+*********************************************************************/
+
+static BOOL ads_dns_parse_rr_ns( TALLOC_CTX *ctx, uint8 *start, uint8 *end,
+ uint8 **ptr, struct dns_rr_ns *nsrec )
+{
+ struct dns_rr rr;
+ uint8 *p;
+ pstring nsname;
+ int namelen;
+
+ if ( !start || !end || !nsrec || !*ptr)
+ return -1;
+
+ /* Parse the RR entry. Coming out of the this, ptr is at the beginning
+ of the next record */
+
+ if ( !ads_dns_parse_rr( ctx, start, end, ptr, &rr ) ) {
+ DEBUG(1,("ads_dns_parse_rr_ns: Failed to parse RR record\n"));
+ return False;
+ }
+
+ if ( rr.type != T_NS ) {
+ DEBUG(1,("ads_dns_parse_rr_ns: Bad answer type (%d)\n", rr.type));
+ return False;
+ }
+
+ p = rr.rdata;
+
+ /* ame server hostname */
+
+ namelen = dn_expand( start, end, p, nsname, sizeof(nsname) );
+ if ( namelen < 0 ) {
+ DEBUG(1,("ads_dns_parse_rr_ns: Failed to uncompress name!\n"));
+ return False;
+ }
+ nsrec->hostname = talloc_strdup( ctx, nsname );
+
+ return True;
+}
/*********************************************************************
Sort SRV record list based on weight and priority. See RFC 2782.
@@ -230,27 +271,16 @@ static int dnssrvcmp( struct dns_rr_srv *a, struct dns_rr_srv *b )
}
/*********************************************************************
- Simple wrapper for a DNS SRV query
+ Simple wrapper for a DNS query
*********************************************************************/
-NTSTATUS ads_dns_lookup_srv( TALLOC_CTX *ctx, const char *name, struct dns_rr_srv **dclist, int *numdcs )
+static NTSTATUS dns_send_req( TALLOC_CTX *ctx, const char *name, int q_type,
+ uint8 **buf, int *resp_length )
{
uint8 *buffer = NULL;
size_t buf_len;
- int resp_len = NS_PACKETSZ;
- struct dns_rr_srv *dcs = NULL;
- int query_count, answer_count, auth_count, additional_count;
- uint8 *p = buffer;
- int rrnum;
- int idx = 0;
-
- if ( !ctx || !name || !dclist ) {
- return NT_STATUS_INVALID_PARAMETER;
- }
+ int resp_len = NS_PACKETSZ;
- /* Send the request. May have to loop several times in case
- of large replies */
-
do {
if ( buffer )
TALLOC_FREE( buffer );
@@ -262,13 +292,47 @@ NTSTATUS ads_dns_lookup_srv( TALLOC_CTX *ctx, const char *name, struct dns_rr_sr
return NT_STATUS_NO_MEMORY;
}
- if ( (resp_len = res_query(name, C_IN, T_SRV, buffer, buf_len)) < 0 ) {
+ if ( (resp_len = res_query(name, C_IN, q_type, buffer, buf_len)) < 0 ) {
DEBUG(1,("ads_dns_lookup_srv: Failed to resolve %s (%s)\n", name, strerror(errno)));
TALLOC_FREE( buffer );
return NT_STATUS_UNSUCCESSFUL;
}
} while ( buf_len < resp_len && resp_len < MAX_DNS_PACKET_SIZE );
+
+ *buf = buffer;
+ *resp_length = resp_len;
+
+ return NT_STATUS_OK;
+}
+
+/*********************************************************************
+ Simple wrapper for a DNS SRV query
+*********************************************************************/
+
+static NTSTATUS ads_dns_lookup_srv( TALLOC_CTX *ctx, const char *name, struct dns_rr_srv **dclist, int *numdcs )
+{
+ uint8 *buffer = NULL;
+ int resp_len = 0;
+ struct dns_rr_srv *dcs = NULL;
+ int query_count, answer_count, auth_count, additional_count;
+ uint8 *p = buffer;
+ int rrnum;
+ int idx = 0;
+ NTSTATUS status;
+
+ if ( !ctx || !name || !dclist ) {
+ return NT_STATUS_INVALID_PARAMETER;
+ }
+
+ /* Send the request. May have to loop several times in case
+ of large replies */
+ status = dns_send_req( ctx, name, T_SRV, &buffer, &resp_len );
+ if ( !NT_STATUS_IS_OK(status) ) {
+ DEBUG(0,("ads_dns_lookup_srv: Failed to send DNS query (%s)\n",
+ nt_errstr(status)));
+ return status;
+ }
p = buffer;
/* For some insane reason, the ns_initparse() et. al. routines are only
@@ -361,6 +425,125 @@ NTSTATUS ads_dns_lookup_srv( TALLOC_CTX *ctx, const char *name, struct dns_rr_sr
return NT_STATUS_OK;
}
+/*********************************************************************
+ Simple wrapper for a DNS NS query
+*********************************************************************/
+
+NTSTATUS ads_dns_lookup_ns( TALLOC_CTX *ctx, const char *dnsdomain, struct dns_rr_ns **nslist, int *numns )
+{
+ uint8 *buffer = NULL;
+ int resp_len = 0;
+ struct dns_rr_ns *nsarray = NULL;
+ int query_count, answer_count, auth_count, additional_count;
+ uint8 *p;
+ int rrnum;
+ int idx = 0;
+ NTSTATUS status;
+
+ if ( !ctx || !dnsdomain || !nslist ) {
+ return NT_STATUS_INVALID_PARAMETER;
+ }
+
+ /* Send the request. May have to loop several times in case
+ of large replies */
+
+ status = dns_send_req( ctx, dnsdomain, T_NS, &buffer, &resp_len );
+ if ( !NT_STATUS_IS_OK(status) ) {
+ DEBUG(0,("ads_dns_lookup_ns: Failed to send DNS query (%s)\n",
+ nt_errstr(status)));
+ return status;
+ }
+ p = buffer;
+
+ /* For some insane reason, the ns_initparse() et. al. routines are only
+ available in libresolv.a, and not the shared lib. Who knows why....
+ So we have to parse the DNS reply ourselves */
+
+ /* Pull the answer RR's count from the header. Use the NMB ordering macros */
+
+ query_count = RSVAL( p, 4 );
+ answer_count = RSVAL( p, 6 );
+ auth_count = RSVAL( p, 8 );
+ additional_count = RSVAL( p, 10 );
+
+ DEBUG(4,("ads_dns_lookup_ns: %d records returned in the answer section.\n",
+ answer_count));
+
+ if ( (nsarray = TALLOC_ARRAY(ctx, struct dns_rr_ns, answer_count)) == NULL ) {
+ DEBUG(0,("ads_dns_lookup_ns: talloc() failure for %d char*'s\n",
+ answer_count));
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ /* now skip the header */
+
+ p += NS_HFIXEDSZ;
+
+ /* parse the query section */
+
+ for ( rrnum=0; rrnum<query_count; rrnum++ ) {
+ struct dns_query q;
+
+ if ( !ads_dns_parse_query( ctx, buffer, buffer+resp_len, &p, &q ) ) {
+ DEBUG(1,("ads_dns_lookup_ns: Failed to parse query record!\n"));
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+ }
+
+ /* now we are at the answer section */
+
+ for ( rrnum=0; rrnum<answer_count; rrnum++ ) {
+ if ( !ads_dns_parse_rr_ns( ctx, buffer, buffer+resp_len, &p, &nsarray[rrnum] ) ) {
+ DEBUG(1,("ads_dns_lookup_ns: Failed to parse answer record!\n"));
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+ }
+ idx = rrnum;
+
+ /* Parse the authority section */
+ /* just skip these for now */
+
+ for ( rrnum=0; rrnum<auth_count; rrnum++ ) {
+ struct dns_rr rr;
+
+ if ( !ads_dns_parse_rr( ctx, buffer, buffer+resp_len, &p, &rr ) ) {
+ DEBUG(1,("ads_dns_lookup_ns: Failed to parse authority record!\n"));
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+ }
+
+ /* Parse the additional records section */
+
+ for ( rrnum=0; rrnum<additional_count; rrnum++ ) {
+ struct dns_rr rr;
+ int i;
+
+ if ( !ads_dns_parse_rr( ctx, buffer, buffer+resp_len, &p, &rr ) ) {
+ DEBUG(1,("ads_dns_lookup_ns: Failed to parse additional records section!\n"));
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+
+ /* only interested in A records as a shortcut for having to come
+ back later and lookup the name */
+
+ if ( (rr.type != T_A) || (rr.rdatalen != 4) )
+ continue;
+
+ for ( i=0; i<idx; i++ ) {
+ if ( strcmp( rr.hostname, nsarray[i].hostname ) == 0 ) {
+ uint8 *buf = (uint8*)&nsarray[i].ip.s_addr;
+ memcpy( buf, rr.rdata, 4 );
+ }
+ }
+ }
+
+ *nslist = nsarray;
+ *numns = idx;
+
+ return NT_STATUS_OK;
+}
+
+
/********************************************************************
********************************************************************/
generated by cgit (git 2.34.1) at 2024-11-06 22:58:06 +0000