Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 841 insertions, 0 deletions

diff --git a/source3/nmbd/nmbd_incomingdgrams.c b/source3/nmbd/nmbd_incomingdgrams.c
new file mode 100644
index 0000000..3e27ff5
--- /dev/null
+++ b/source3/nmbd/nmbd_incomingdgrams.c
@@ -0,0 +1,841 @@
+/*
+   Unix SMB/CIFS implementation.
+   NBT netbios routines and daemon - version 2
+   Copyright (C) Andrew Tridgell 1994-1998
+   Copyright (C) Luke Kenneth Casson Leighton 1994-1998
+   Copyright (C) Jeremy Allison 1994-1998
+
+   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 3 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, see <http://www.gnu.org/licenses/>.
+
+*/
+
+#include "includes.h"
+#include "../librpc/gen_ndr/svcctl.h"
+#include "nmbd/nmbd.h"
+#include "lib/util/string_wrappers.h"
+
+extern bool found_lm_clients;
+
+#if 0
+
+/* XXXX note: This function is currently unsuitable for use, as it
+   does not properly check that a server is in a fit state to become
+   a backup browser before asking it to be one.
+   The code is left here to be worked on at a later date.
+*/
+
+/****************************************************************************
+Tell a server to become a backup browser
+**************************************************************************/
+
+void tell_become_backup(void)
+{
+  struct subnet_record *subrec;
+  for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec))
+  {
+    struct work_record *work;
+    for (work = subrec->workgrouplist; work; work = work->next)
+    {
+      struct server_record *servrec;
+      int num_servers = 0;
+      int num_backups = 0;
+
+      for (servrec = work->serverlist; servrec; servrec = servrec->next)
+      {
+        num_servers++;
+
+        if (is_myname(servrec->serv.name))
+          continue;
+
+        if (servrec->serv.type & SV_TYPE_BACKUP_BROWSER)
+        {
+          num_backups++;
+          continue;
+        }
+
+        if (servrec->serv.type & SV_TYPE_MASTER_BROWSER)
+          continue;
+
+        if (!(servrec->serv.type & SV_TYPE_POTENTIAL_BROWSER))
+          continue;
+
+        DEBUG(3,("num servers: %d num backups: %d\n",
+              num_servers, num_backups));
+
+        /* make first server a backup server. thereafter make every
+           tenth server a backup server */
+        if (num_backups != 0 && (num_servers+9) / num_backups > 10)
+          continue;
+
+        DEBUG(2,("sending become backup to %s %s for %s\n",
+             servrec->serv.name, inet_ntoa(subrec->bcast_ip),
+             work->work_group));
+
+        /* type 11 request from MYNAME(20) to WG(1e) for SERVER */
+        do_announce_request(servrec->serv.name, work->work_group,
+              ANN_BecomeBackup, 0x20, 0x1e, subrec->bcast_ip);
+      }
+    }
+  }
+}
+#endif
+
+/*******************************************************************
+  Process an incoming host announcement packet.
+*******************************************************************/
+
+void process_host_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	int ttl = IVAL(buf,1)/1000;
+	unstring announce_name;
+	uint32_t servertype = IVAL(buf,23);
+	fstring comment;
+	struct work_record *work;
+	struct server_record *servrec;
+	unstring work_name;
+	unstring source_name;
+	ZERO_STRUCT(source_name);
+	ZERO_STRUCT(announce_name);
+
+	pull_ascii_fstring(comment, buf+31);
+
+	pull_ascii_nstring(announce_name, sizeof(announce_name), buf+5);
+	pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
+
+	DEBUG(3,("process_host_announce: from %s<%02x> IP %s to \
+%s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
+			nmb_namestr(&dgram->dest_name),announce_name));
+
+	DEBUG(5,("process_host_announce: ttl=%d server type=%08x comment=%s\n",
+		ttl, servertype,comment));
+
+	/* Filter servertype to remove impossible bits. */
+	servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
+
+	/* A host announcement must be sent to the name WORKGROUP<1d>. */
+	if(dgram->dest_name.name_type != 0x1d) {
+		DEBUG(2,("process_host_announce: incorrect name type for destination from IP %s \
+(was %02x) should be 0x1d. Allowing packet anyway.\n",
+			inet_ntoa(p->ip), dgram->dest_name.name_type));
+		/* Change it so it was. */
+		dgram->dest_name.name_type = 0x1d;
+	}
+
+	/* For a host announce the workgroup name is the destination name. */
+	pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
+
+	/*
+	 * Syntax servers version 5.1 send HostAnnounce packets to
+	 * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
+	 * instead of WORKGROUP<1d> name. So to fix this we check if
+	 * the workgroup name is our own name, and if so change it
+	 * to be our primary workgroup name.
+	 */
+
+	if(strequal(work_name, lp_netbios_name()))
+		unstrcpy(work_name,lp_workgroup());
+
+	/*
+	 * We are being very aggressive here in adding a workgroup
+	 * name on the basis of a host announcing itself as being
+	 * in that workgroup. Maybe we should wait for the workgroup
+	 * announce instead ? JRA.
+	 */
+
+	work = find_workgroup_on_subnet(subrec, work_name);
+
+	if(servertype != 0) {
+		if (work ==NULL ) {
+			/* We have no record of this workgroup. Add it. */
+			if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
+				goto done;
+		}
+
+		if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
+			/* If this server is not already in the workgroup, add it. */
+			create_server_on_workgroup(work, announce_name,
+				servertype|SV_TYPE_LOCAL_LIST_ONLY,
+				ttl, comment);
+		} else {
+			/* Update the record. */
+			servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
+			update_server_ttl( servrec, ttl);
+			strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
+		}
+	} else {
+		/*
+		 * This server is announcing it is going down. Remove it from the
+		 * workgroup.
+		 */
+		if(!is_myname(announce_name) && (work != NULL) &&
+				((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
+			remove_server_from_workgroup( work, servrec);
+		}
+	}
+
+	subrec->work_changed = True;
+done:
+	return;
+}
+
+/*******************************************************************
+  Process an incoming WORKGROUP announcement packet.
+*******************************************************************/
+
+void process_workgroup_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	int ttl = IVAL(buf,1)/1000;
+	unstring workgroup_announce_name;
+	unstring master_name;
+	uint32_t servertype = IVAL(buf,23);
+	struct work_record *work;
+	unstring source_name;
+	unstring dest_name;
+
+	pull_ascii_nstring(workgroup_announce_name,sizeof(workgroup_announce_name),buf+5);
+	pull_ascii_nstring(master_name,sizeof(master_name),buf+31);
+	pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
+	pull_ascii_nstring(dest_name,sizeof(dest_name),dgram->dest_name.name);
+
+	DEBUG(3,("process_workgroup_announce: from %s<%02x> IP %s to \
+%s for workgroup %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
+			nmb_namestr(&dgram->dest_name),workgroup_announce_name));
+
+	DEBUG(5,("process_workgroup_announce: ttl=%d server type=%08x master browser=%s\n",
+		ttl, servertype, master_name));
+
+	/* Workgroup announcements must only go to the MSBROWSE name. */
+	if (!strequal(dest_name, MSBROWSE) || (dgram->dest_name.name_type != 0x1)) {
+		DEBUG(0,("process_workgroup_announce: from IP %s should be to __MSBROWSE__<0x01> not %s\n",
+			inet_ntoa(p->ip), nmb_namestr(&dgram->dest_name)));
+		goto done;
+	}
+
+	if ((work = find_workgroup_on_subnet(subrec, workgroup_announce_name))==NULL) {
+		/* We have no record of this workgroup. Add it. */
+		if((work = create_workgroup_on_subnet(subrec, workgroup_announce_name, ttl))==NULL)
+			goto done;
+	} else {
+		/* Update the workgroup death_time. */
+		update_workgroup_ttl(work, ttl);
+	}
+
+	if(*work->local_master_browser_name == '\0') {
+		/* Set the master browser name. */
+		set_workgroup_local_master_browser_name( work, master_name );
+	}
+
+	subrec->work_changed = True;
+
+done:
+	return;
+}
+
+/*******************************************************************
+  Process an incoming local master browser announcement packet.
+*******************************************************************/
+
+void process_local_master_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	int ttl = IVAL(buf,1)/1000;
+	unstring server_name;
+	uint32_t servertype = IVAL(buf,23);
+	fstring comment;
+	unstring work_name;
+	struct work_record *work = NULL;
+	struct server_record *servrec;
+	unstring source_name;
+
+	pull_ascii_nstring(server_name,sizeof(server_name),buf+5);
+	pull_ascii_fstring(comment, buf+31);
+	pull_ascii_nstring(source_name, sizeof(source_name), dgram->source_name.name);
+	pull_ascii_nstring(work_name, sizeof(work_name), dgram->dest_name.name);
+
+	DEBUG(3,("process_local_master_announce: from %s<%02x> IP %s to \
+%s for server %s.\n", source_name, source_name[15], inet_ntoa(p->ip),
+		nmb_namestr(&dgram->dest_name),server_name));
+
+	DEBUG(5,("process_local_master_announce: ttl=%d server type=%08x comment=%s\n",
+		ttl, servertype, comment));
+
+	/* A local master announcement must be sent to the name WORKGROUP<1e>. */
+	if(dgram->dest_name.name_type != 0x1e) {
+		DEBUG(0,("process_local_master_announce: incorrect name type for destination from IP %s \
+(was %02x) should be 0x1e. Ignoring packet.\n",
+			inet_ntoa(p->ip), dgram->dest_name.name_type));
+		goto done;
+	}
+
+	/* Filter servertype to remove impossible bits. */
+	servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
+
+	/* For a local master announce the workgroup name is the destination name. */
+
+	if ((work = find_workgroup_on_subnet(subrec, work_name))==NULL) {
+		/* Don't bother adding if it's a local master release announce. */
+		if(servertype == 0)
+			goto done;
+
+		/* We have no record of this workgroup. Add it. */
+		if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
+			goto done;
+	}
+
+	/* If we think we're the local master browser for this workgroup,
+		we should never have got this packet. We don't see our own
+		packets.
+	*/
+	if(AM_LOCAL_MASTER_BROWSER(work)) {
+		DEBUG(0,("process_local_master_announce: Server %s at IP %s is announcing itself as \
+a local master browser for workgroup %s and we think we are master. Forcing election.\n",
+			server_name, inet_ntoa(p->ip), work_name));
+
+		/* Samba nmbd versions 1.9.17 to 1.9.17p4 have a bug in that when
+		 they have become a local master browser once, they will never
+		 stop sending local master announcements. To fix this we send
+		 them a reset browser packet, with level 0x2 on the __SAMBA__
+		 name that only they should be listening to. */
+
+		send_browser_reset( 0x2, "__SAMBA__" , 0x20, p->ip);
+
+		/* We should demote ourself and force an election. */
+
+		unbecome_local_master_browser( subrec, work, True);
+
+		/* The actual election requests are handled in nmbd_election.c */
+		goto done;
+	}
+
+	/* Find the server record on this workgroup. If it doesn't exist, add it. */
+
+	if(servertype != 0) {
+		if((servrec = find_server_in_workgroup( work, server_name))==NULL) {
+			/* If this server is not already in the workgroup, add it. */
+			create_server_on_workgroup(work, server_name,
+				servertype|SV_TYPE_LOCAL_LIST_ONLY,
+				ttl, comment);
+		} else {
+			/* Update the record. */
+			if (servrec->serv.type !=
+					(servertype|SV_TYPE_LOCAL_LIST_ONLY)) {
+				servrec->serv.type =
+					servertype|SV_TYPE_LOCAL_LIST_ONLY;
+				subrec->work_changed = true;
+			}
+			if (!strequal(servrec->serv.comment,comment)) {
+				strlcpy(servrec->serv.comment,
+					comment,
+					sizeof(servrec->serv.comment));
+				subrec->work_changed = true;
+			}
+			update_server_ttl(servrec, ttl);
+		}
+
+		if (!strequal(work->local_master_browser_name, server_name)) {
+			set_workgroup_local_master_browser_name( work, server_name );
+			subrec->work_changed = true;
+		}
+	} else {
+		/*
+		 * This server is announcing it is going down. Remove it from the
+		 * workgroup.
+		 */
+		if(!is_myname(server_name) &&
+				((servrec = find_server_in_workgroup( work, server_name))!=NULL)) {
+			remove_server_from_workgroup( work, servrec);
+		}
+	}
+
+done:
+	return;
+}
+
+/*******************************************************************
+  Process a domain master announcement frame.
+  Domain master browsers receive these from local masters. The Domain
+  master should then issue a sync with the local master, asking for
+  that machines local server list.
+******************************************************************/
+
+void process_master_browser_announce(struct subnet_record *subrec,
+                                     struct packet_struct *p,const char *buf)
+{
+	unstring local_master_name;
+	struct work_record *work;
+	struct browse_cache_record *browrec;
+
+	pull_ascii_nstring(local_master_name,sizeof(local_master_name),buf);
+
+	DEBUG(3,("process_master_browser_announce: Local master announce from %s IP %s.\n",
+		local_master_name, inet_ntoa(p->ip)));
+
+	if (!lp_domain_master()) {
+		DEBUG(0,("process_master_browser_announce: Not configured as domain \
+master - ignoring master announce.\n"));
+		goto done;
+	}
+
+	if((work = find_workgroup_on_subnet(subrec, lp_workgroup())) == NULL) {
+		DEBUG(0,("process_master_browser_announce: Cannot find workgroup %s on subnet %s\n",
+			lp_workgroup(), subrec->subnet_name));
+		goto done;
+	}
+
+	if(!AM_DOMAIN_MASTER_BROWSER(work)) {
+		DEBUG(0,("process_master_browser_announce: Local master announce made to us from \
+%s IP %s and we are not a domain master browser.\n", local_master_name, inet_ntoa(p->ip)));
+		goto done;
+	}
+
+	/* Add this host as a local master browser entry on the browse lists.
+		This causes a sync request to be made to it at a later date.
+	*/
+
+	if((browrec = find_browser_in_lmb_cache( local_master_name )) == NULL) {
+		/* Add it. */
+		create_browser_in_lmb_cache( work->work_group, local_master_name, p->ip);
+	} else {
+		update_browser_death_time(browrec);
+	}
+
+done:
+	return;
+}
+
+/*******************************************************************
+  Process an incoming LanMan host announcement packet.
+*******************************************************************/
+
+void process_lm_host_announce(struct subnet_record *subrec, struct packet_struct *p, const char *buf, int len)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	uint32_t servertype = IVAL(buf,1);
+	int osmajor=CVAL(buf,5);           /* major version of node software */
+	int osminor=CVAL(buf,6);           /* minor version of node software */
+	int ttl = SVAL(buf,7);
+	unstring announce_name;
+	struct work_record *work;
+	struct server_record *servrec;
+	unstring work_name;
+	unstring source_name;
+	fstring comment;
+	char *s = get_safe_str_ptr(buf,len,discard_const_p(char, buf),9);
+
+	if (!s) {
+		goto done;
+	}
+	s = skip_string(buf,len,s);
+	if (!s) {
+		goto done;
+	}
+	pull_ascii(comment, s, sizeof(fstring), 43, STR_TERMINATE);
+
+	pull_ascii_nstring(announce_name,sizeof(announce_name),buf+9);
+	pull_ascii_nstring(source_name,sizeof(source_name),dgram->source_name.name);
+	/* For a LanMan host announce the workgroup name is the destination name. */
+	pull_ascii_nstring(work_name,sizeof(work_name),dgram->dest_name.name);
+
+	DEBUG(3,("process_lm_host_announce: LM Announcement from %s IP %s to \
+%s for server %s.\n", nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
+		nmb_namestr(&dgram->dest_name),announce_name));
+
+	DEBUG(5,("process_lm_host_announce: os=(%d,%d) ttl=%d server type=%08x comment=%s\n",
+		osmajor, osminor, ttl, servertype,comment));
+
+	if ((osmajor < 36) || (osmajor > 38) || (osminor !=0)) {
+		DEBUG(5,("process_lm_host_announce: LM Announcement packet does not \
+originate from OS/2 Warp client. Ignoring packet.\n"));
+		/* Could have been from a Windows machine (with its LM Announce enabled),
+			or a Samba server. Then don't disrupt the current browse list. */
+		goto done;
+	}
+
+	/* Filter servertype to remove impossible bits. */
+	servertype &= ~(SV_TYPE_LOCAL_LIST_ONLY|SV_TYPE_DOMAIN_ENUM);
+
+	/* A LanMan host announcement must be sent to the name WORKGROUP<00>. */
+	if(dgram->dest_name.name_type != 0x00) {
+		DEBUG(2,("process_lm_host_announce: incorrect name type for destination from IP %s \
+(was %02x) should be 0x00. Allowing packet anyway.\n",
+			inet_ntoa(p->ip), dgram->dest_name.name_type));
+		/* Change it so it was. */
+		dgram->dest_name.name_type = 0x00;
+	}
+
+	/*
+	 * Syntax servers version 5.1 send HostAnnounce packets to
+	 * *THE WRONG NAME*. They send to LOCAL_MASTER_BROWSER_NAME<00>
+	 * instead of WORKGROUP<1d> name. So to fix this we check if
+	 * the workgroup name is our own name, and if so change it
+	 * to be our primary workgroup name. This code is probably
+	 * not needed in the LanMan announce code, but it won't hurt.
+	 */
+
+	if(strequal(work_name, lp_netbios_name()))
+		unstrcpy(work_name,lp_workgroup());
+
+	/*
+	 * We are being very aggressive here in adding a workgroup
+	 * name on the basis of a host announcing itself as being
+	 * in that workgroup. Maybe we should wait for the workgroup
+	 * announce instead ? JRA.
+	 */
+
+	work = find_workgroup_on_subnet(subrec, work_name);
+
+	if(servertype != 0) {
+		if (work == NULL) {
+			/* We have no record of this workgroup. Add it. */
+			if((work = create_workgroup_on_subnet(subrec, work_name, ttl))==NULL)
+				goto done;
+		}
+
+		if((servrec = find_server_in_workgroup( work, announce_name))==NULL) {
+			/* If this server is not already in the workgroup, add it. */
+			create_server_on_workgroup(work, announce_name,
+					servertype|SV_TYPE_LOCAL_LIST_ONLY,
+					ttl, comment);
+		} else {
+			/* Update the record. */
+			servrec->serv.type = servertype|SV_TYPE_LOCAL_LIST_ONLY;
+			update_server_ttl( servrec, ttl);
+			strlcpy(servrec->serv.comment,comment,sizeof(servrec->serv.comment));
+		}
+	} else {
+		/*
+		 * This server is announcing it is going down. Remove it from the
+		 * workgroup.
+		 */
+		if(!is_myname(announce_name) && (work != NULL) &&
+				((servrec = find_server_in_workgroup( work, announce_name))!=NULL)) {
+			remove_server_from_workgroup( work, servrec);
+		}
+	}
+
+	subrec->work_changed = True;
+	found_lm_clients = True;
+
+done:
+	return;
+}
+
+/****************************************************************************
+  Send a backup list response.
+*****************************************************************************/
+
+static void send_backup_list_response(struct subnet_record *subrec,
+				      struct work_record *work,
+				      struct nmb_name *send_to_name,
+				      unsigned char max_number_requested,
+				      uint32_t token, struct in_addr sendto_ip,
+				      int port)
+{
+	char outbuf[1024];
+	char *p, *countptr;
+	unsigned int count = 0;
+	unstring send_to_namestr;
+#if 0
+  struct server_record *servrec;
+#endif
+	unstring myname;
+
+	memset(outbuf,'\0',sizeof(outbuf));
+
+	DEBUG(3,("send_backup_list_response: sending backup list for workgroup %s to %s IP %s\n",
+		work->work_group, nmb_namestr(send_to_name), inet_ntoa(sendto_ip)));
+
+	p = outbuf;
+
+	SCVAL(p,0,ANN_GetBackupListResp); /* Backup list response opcode. */
+	p++;
+
+	countptr = p;
+	p++;
+
+	SIVAL(p,0,token); /* The sender's unique info. */
+	p += 4;
+
+	/* We always return at least one name - our own. */
+	count = 1;
+	unstrcpy(myname, lp_netbios_name());
+	if (!strupper_m(myname)) {
+		DEBUG(4,("strupper_m %s failed\n", myname));
+		return;
+	}
+	myname[15]='\0';
+	push_ascii(p, myname, sizeof(outbuf)-PTR_DIFF(p,outbuf)-1, STR_TERMINATE);
+
+	p = skip_string(outbuf,sizeof(outbuf),p);
+
+	/* Look for backup browsers in this workgroup. */
+
+#if 0
+  /* we don't currently send become_backup requests so we should never
+     send any other servers names out as backups for our
+     workgroup. That's why this is commented out (tridge) */
+
+  /*
+   * NB. Note that the struct work_record here is not necessarily
+   * attached to the subnet *subrec.
+   */
+
+  for (servrec = work->serverlist; servrec; servrec = servrec->next)
+  {
+    int len = PTR_DIFF(p, outbuf);
+    if((sizeof(outbuf) - len) < 16)
+      break;
+
+    if(count >= (unsigned int)max_number_requested)
+      break;
+
+    if(strnequal(servrec->serv.name, lp_netbios_name(),15))
+      continue;
+
+    if(!(servrec->serv.type & SV_TYPE_BACKUP_BROWSER))
+      continue;
+
+    strlcpy(p, servrec->serv.name, 16);
+    strupper_m(p);
+    count++;
+
+    DEBUG(5,("send_backup_list_response: Adding server %s number %d\n",
+              p, count));
+
+    p = skip_string(outbuf,sizeof(outbuf),p);
+  }
+#endif
+
+	SCVAL(countptr, 0, count);
+
+	pull_ascii_nstring(send_to_namestr, sizeof(send_to_namestr), send_to_name->name);
+
+	DEBUG(4,("send_backup_list_response: sending response to %s<00> IP %s with %d servers.\n",
+		send_to_namestr, inet_ntoa(sendto_ip), count));
+
+	send_mailslot(True, BROWSE_MAILSLOT,
+		outbuf,PTR_DIFF(p,outbuf),
+		lp_netbios_name(), 0,
+		send_to_namestr,0,
+		sendto_ip, subrec->myip, port);
+}
+
+/*******************************************************************
+  Process a send backup list request packet.
+
+  A client sends a backup list request to ask for a list of servers on
+  the net that maintain server lists for a domain. A server is then
+  chosen from this list to send NetServerEnum commands to to list
+  available servers.
+
+********************************************************************/
+
+void process_get_backup_list_request(struct subnet_record *subrec,
+                                     struct packet_struct *p,const char *buf)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	struct work_record *work;
+	unsigned char max_number_requested = CVAL(buf,0);
+	uint32_t token = IVAL(buf,1); /* Sender's key index for the workgroup. */
+	int name_type = dgram->dest_name.name_type;
+	unstring workgroup_name;
+	struct subnet_record *search_subrec = subrec;
+
+	pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
+
+	DEBUG(3,("process_get_backup_list_request: request from %s IP %s to %s.\n",
+		nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
+		nmb_namestr(&dgram->dest_name)));
+
+	/* We have to be a master browser, or a domain master browser
+		for the requested workgroup. That means it must be our
+		workgroup. */
+
+	if(strequal(workgroup_name, lp_workgroup()) == False) {
+		DEBUG(7,("process_get_backup_list_request: Ignoring announce request for workgroup %s.\n",
+			workgroup_name));
+		goto done;
+	}
+
+	if((work = find_workgroup_on_subnet(search_subrec, workgroup_name)) == NULL) {
+		DEBUG(0,("process_get_backup_list_request: Cannot find workgroup %s on \
+subnet %s.\n", workgroup_name, search_subrec->subnet_name));
+		goto done;
+	}
+
+	/*
+	 * If the packet was sent to WORKGROUP<1b> instead
+	 * of WORKGROUP<1d> then it was unicast to us a domain master
+	 * browser. Change search subrec to unicast.
+	 */
+
+	if(name_type == 0x1b) {
+		/* We must be a domain master browser in order to
+			process this packet. */
+
+		if(!AM_DOMAIN_MASTER_BROWSER(work)) {
+			DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
+and I am not a domain master browser.\n", workgroup_name));
+			goto done;
+		}
+
+		search_subrec = unicast_subnet;
+	} else if (name_type == 0x1d) {
+		/* We must be a local master browser in order to process this packet. */
+
+		if(!AM_LOCAL_MASTER_BROWSER(work)) {
+			DEBUG(0,("process_get_backup_list_request: domain list requested for workgroup %s \
+and I am not a local master browser.\n", workgroup_name));
+			goto done;
+		}
+	} else {
+		DEBUG(0,("process_get_backup_list_request: Invalid name type %x - should be 0x1b or 0x1d.\n",
+			name_type));
+		goto done;
+	}
+
+	send_backup_list_response(subrec, work, &dgram->source_name,
+			max_number_requested, token, p->ip, p->port);
+
+done:
+	return;
+}
+
+/*******************************************************************
+  Process a reset browser state packet.
+
+  Diagnostic packet:
+  0x1 - Stop being a master browser and become a backup browser.
+  0x2 - Discard browse lists, stop being a master browser, try again.
+  0x4 - Stop being a master browser forever.
+
+******************************************************************/
+
+void process_reset_browser(struct subnet_record *subrec,
+                                  struct packet_struct *p,const char *buf)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	int state = CVAL(buf,0);
+	struct subnet_record *sr;
+
+	DEBUG(1,("process_reset_browser: received diagnostic browser reset \
+request from %s IP %s state=0x%X\n",
+		nmb_namestr(&dgram->source_name), inet_ntoa(p->ip), state));
+
+	/* Stop being a local master browser on all our broadcast subnets. */
+	if (state & 0x1) {
+		for (sr = FIRST_SUBNET; sr; sr = NEXT_SUBNET_EXCLUDING_UNICAST(sr)) {
+			struct work_record *work;
+			for (work = sr->workgrouplist; work; work = work->next) {
+				if (AM_LOCAL_MASTER_BROWSER(work))
+					unbecome_local_master_browser(sr, work, True);
+			}
+		}
+	}
+
+	/* Discard our browse lists. */
+	if (state & 0x2) {
+		/*
+		 * Calling expire_workgroups_and_servers with a -1
+		 * time causes all servers not marked with a PERMANENT_TTL
+		 * on the workgroup lists to be discarded, and all
+		 * workgroups with empty server lists to be discarded.
+		 * This means we keep our own server names and workgroup
+		 * as these have a PERMANENT_TTL.
+		 */
+
+		expire_workgroups_and_servers(-1);
+	}
+
+	/* Request to stop browsing altogether. */
+	if (state & 0x4)
+		DEBUG(1,("process_reset_browser: ignoring request to stop being a browser.\n"));
+}
+
+/*******************************************************************
+  Process an announcement request packet.
+  We don't respond immediately, we just check it's a request for
+  our workgroup and then set the flag telling the announce code
+  in nmbd_sendannounce.c:announce_my_server_names that an
+  announcement is needed soon.
+******************************************************************/
+
+void process_announce_request(struct subnet_record *subrec, struct packet_struct *p, const char *buf)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	struct work_record *work;
+	unstring workgroup_name;
+
+	pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
+	DEBUG(3,("process_announce_request: Announce request from %s IP %s to %s.\n",
+		nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
+		nmb_namestr(&dgram->dest_name)));
+
+	/* We only send announcement requests on our workgroup. */
+	if(strequal(workgroup_name, lp_workgroup()) == False) {
+		DEBUG(7,("process_announce_request: Ignoring announce request for workgroup %s.\n",
+			workgroup_name));
+		goto done;
+	}
+
+	if((work = find_workgroup_on_subnet(subrec, workgroup_name)) == NULL) {
+		DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
+			workgroup_name));
+		goto done;
+	}
+
+	work->needannounce = True;
+done:
+	return;
+}
+
+/*******************************************************************
+  Process a LanMan announcement request packet.
+  We don't respond immediately, we just check it's a request for
+  our workgroup and then set the flag telling that we have found
+  a LanMan client (DOS or OS/2) and that we will have to start
+  sending LanMan announcements (unless specifically disabled
+  through the "lm announce" parameter in smb.conf)
+******************************************************************/
+
+void process_lm_announce_request(struct subnet_record *subrec, struct packet_struct *p, const char *buf, int len)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	unstring workgroup_name;
+
+	pull_ascii_nstring(workgroup_name, sizeof(workgroup_name), dgram->dest_name.name);
+	DEBUG(3,("process_lm_announce_request: Announce request from %s IP %s to %s.\n",
+		nmb_namestr(&dgram->source_name), inet_ntoa(p->ip),
+		nmb_namestr(&dgram->dest_name)));
+
+	/* We only send announcement requests on our workgroup. */
+	if(strequal(workgroup_name, lp_workgroup()) == False) {
+		DEBUG(7,("process_lm_announce_request: Ignoring announce request for workgroup %s.\n",
+			workgroup_name));
+		goto done;
+	}
+
+	if(find_workgroup_on_subnet(subrec, workgroup_name) == NULL) {
+		DEBUG(0,("process_announce_request: Unable to find workgroup %s on subnet !\n",
+			workgroup_name));
+		goto done;
+	}
+
+	found_lm_clients = True;
+
+done:
+	return;
+}