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-rw-r--r--source3/nmbd/asyncdns.c257
-rw-r--r--source3/nmbd/nmbd.c13
2 files changed, 262 insertions, 8 deletions
diff --git a/source3/nmbd/asyncdns.c b/source3/nmbd/asyncdns.c
new file mode 100644
index 0000000000..548781edea
--- /dev/null
+++ b/source3/nmbd/asyncdns.c
@@ -0,0 +1,257 @@
+/*
+ Unix SMB/Netbios implementation.
+ Version 1.9.
+ a async DNS handler
+ Copyright (C) Andrew Tridgell 1994-1997
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ Revision History:
+
+ 14 jan 96: lkcl@pires.co.uk
+ added multiple workgroup domain master support
+
+*/
+
+#include "includes.h"
+
+extern int DEBUGLEVEL;
+
+
+/***************************************************************************
+ add a DNS result to the name cache
+ ****************************************************************************/
+static struct name_record *add_dns_result(struct nmb_name *question, struct in_addr addr)
+{
+ int name_type = question->name_type;
+ char *qname = question->name;
+
+ if (!addr.s_addr) {
+ /* add the fail to WINS cache of names. give it 1 hour in the cache */
+ DEBUG(3,("Negative DNS answer for %s\n", qname));
+ add_netbios_entry(wins_subnet,qname,name_type,NB_ACTIVE,60*60,DNSFAIL,addr,
+ True, True);
+ return NULL;
+ }
+
+ /* add it to our WINS cache of names. give it 2 hours in the cache */
+ DEBUG(3,("DNS gave answer for %s of %s\n", qname, inet_ntoa(addr)));
+
+ return add_netbios_entry(wins_subnet,qname,name_type,NB_ACTIVE,2*60*60,DNS,addr,
+ True,True);
+}
+
+
+
+#ifndef SYNC_DNS
+
+static int fd_in = -1, fd_out = -1;
+static int child_pid = -1;
+static int in_dns;
+
+/* this is the structure that is passed between the parent and child */
+struct query_record {
+ struct nmb_name name;
+ struct in_addr result;
+};
+
+/* a queue of pending requests waiting for DNS responses */
+static struct packet_struct *dns_queue;
+
+
+
+/***************************************************************************
+ return the fd used to gather async dns replies. This is added to the select
+ loop
+ ****************************************************************************/
+int asyncdns_fd(void)
+{
+ return fd_in;
+}
+
+/***************************************************************************
+ handle DNS queries arriving from the parent
+ ****************************************************************************/
+static void asyncdns_process(void)
+{
+ struct query_record r;
+ fstring qname;
+
+ DEBUGLEVEL = 0;
+
+ while (1) {
+ if (read_data(fd_in, (char *)&r, sizeof(r)) != sizeof(r))
+ break;
+
+ fstrcpy(qname, r.name.name);
+
+ r.result.s_addr = interpret_addr(qname);
+
+ if (write_data(fd_out, (char *)&r, sizeof(r)) != sizeof(r))
+ break;
+ }
+
+ exit(0);
+}
+
+
+/***************************************************************************
+ create a child process to handle DNS lookups
+ ****************************************************************************/
+void start_async_dns(void)
+{
+ int fd1[2], fd2[2];
+
+ signal(SIGCLD, SIG_IGN);
+
+ if (pipe(fd1) || pipe(fd2)) {
+ return;
+ }
+
+ child_pid = fork();
+
+ if (child_pid) {
+ fd_in = fd1[0];
+ fd_out = fd2[1];
+ close(fd1[1]);
+ close(fd2[0]);
+ DEBUG(3,("async DNS initialised\n"));
+ return;
+ }
+
+ fd_in = fd2[0];
+ fd_out = fd1[1];
+
+ asyncdns_process();
+}
+
+
+/***************************************************************************
+check if a particular name is already being queried
+ ****************************************************************************/
+static BOOL query_in_queue(struct query_record *r)
+{
+ struct packet_struct *p;
+ for (p = dns_queue; p; p = p->next) {
+ struct nmb_packet *nmb = &p->packet.nmb;
+ struct nmb_name *question = &nmb->question.question_name;
+
+ if (name_equal(question, &r->name))
+ return True;
+ }
+ return False;
+}
+
+
+/***************************************************************************
+ check the DNS queue
+ ****************************************************************************/
+void run_dns_queue(void)
+{
+ struct query_record r;
+ struct packet_struct *p, *p2;
+
+ if (fd_in == -1)
+ return;
+
+ if (read_data(fd_in, (char *)&r, sizeof(r)) != sizeof(r)) {
+ DEBUG(0,("Incomplete DNS answer from child!\n"));
+ fd_in = -1;
+ return;
+ }
+
+ add_dns_result(&r.name, r.result);
+
+ /* loop over the whole dns queue looking for entries that
+ match the result we just got */
+ for (p = dns_queue; p;) {
+ struct nmb_packet *nmb = &p->packet.nmb;
+ struct nmb_name *question = &nmb->question.question_name;
+
+ if (name_equal(question, &r.name)) {
+ DEBUG(3,("DNS calling reply_name_query\n"));
+ in_dns = 1;
+ reply_name_query(p);
+ in_dns = 0;
+ p->locked = False;
+
+ if (p->prev)
+ p->prev->next = p->next;
+ else
+ dns_queue = p->next;
+ if (p->next)
+ p->next->prev = p->prev;
+ p2 = p->next;
+ free_packet(p);
+ p = p2;
+ } else {
+ p = p->next;
+ }
+ }
+
+}
+
+/***************************************************************************
+queue a DNS query
+ ****************************************************************************/
+BOOL queue_dns_query(struct packet_struct *p,struct nmb_name *question,
+ struct name_record **n)
+{
+ struct query_record r;
+
+ if (in_dns || fd_in == -1)
+ return False;
+
+ r.name = *question;
+
+ if (!query_in_queue(&r) &&
+ !write_data(fd_out, (char *)&r, sizeof(r))) {
+ DEBUG(3,("failed to send DNS query to child!\n"));
+ return False;
+ }
+
+ p->locked = True;
+ p->next = dns_queue;
+ p->prev = NULL;
+ if (p->next)
+ p->next->prev = p;
+ dns_queue = p;
+
+
+ DEBUG(3,("added DNS query for %s\n", namestr(question)));
+ return True;
+}
+
+#else
+
+
+/***************************************************************************
+ we use this then we can't do async DNS lookups
+ ****************************************************************************/
+BOOL queue_dns_query(struct packet_struct *p,struct nmb_name *question,
+ struct name_record **n)
+{
+ int name_type = question->name_type;
+ char *qname = question->name;
+ struct in_addr dns_ip;
+
+ DEBUG(3,("DNS search for %s - ", namestr(question)));
+
+ dns_ip.s_addr = interpret_addr(qname);
+
+ *n = add_dns_result(question, dns_ip);
+ return False;
+}
+#endif
diff --git a/source3/nmbd/nmbd.c b/source3/nmbd/nmbd.c
index 047284832f..5feeb07c90 100644
--- a/source3/nmbd/nmbd.c
+++ b/source3/nmbd/nmbd.c
@@ -332,14 +332,6 @@ static void process(void)
****************************************************************************/
static BOOL open_sockets(BOOL isdaemon, int port)
{
- struct hostent *hp;
-
- /* get host info */
- if ((hp = Get_Hostbyname(myhostname)) == 0) {
- DEBUG(0,( "Get_Hostbyname: Unknown host. %s\n",myhostname));
- return False;
- }
-
/* The sockets opened here will be used to receive broadcast
packets *only*. Interface specific sockets are opened in
make_subnet() in namedbsubnet.c. Thus we bind to the
@@ -598,6 +590,10 @@ static void usage(char *pname)
become_daemon();
}
+#ifndef SYNC_DNS
+ start_async_dns();
+#endif
+
if (*pidFile)
{
int fd;
@@ -653,6 +649,7 @@ static void usage(char *pname)
/* We can only take sigterm signals in the select. */
BlockSignals(True,SIGTERM);
+
process();
close_sockets();