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-rw-r--r--source4/nmbd/nmbd_incomingrequests.c596
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diff --git a/source4/nmbd/nmbd_incomingrequests.c b/source4/nmbd/nmbd_incomingrequests.c
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+++ b/source4/nmbd/nmbd_incomingrequests.c
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+/*
+ 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 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.
+
+ This file contains all the code to process NetBIOS requests coming
+ in on port 137. It does not deal with the code needed to service
+ WINS server requests, but only broadcast and unicast requests.
+
+*/
+
+#include "includes.h"
+
+/****************************************************************************
+Send a name release response.
+**************************************************************************/
+
+static void send_name_release_response(int rcode, struct packet_struct *p)
+{
+ struct nmb_packet *nmb = &p->packet.nmb;
+ char rdata[6];
+
+ memcpy(&rdata[0], &nmb->additional->rdata[0], 6);
+
+ reply_netbios_packet(p, /* Packet to reply to. */
+ rcode, /* Result code. */
+ NMB_REL, /* nmbd type code. */
+ NMB_NAME_RELEASE_OPCODE, /* opcode. */
+ 0, /* ttl. */
+ rdata, /* data to send. */
+ 6); /* data length. */
+}
+
+/****************************************************************************
+Process a name release packet on a broadcast subnet.
+Ignore it if it's not one of our names.
+****************************************************************************/
+
+void process_name_release_request(struct subnet_record *subrec,
+ struct packet_struct *p)
+{
+ struct nmb_packet *nmb = &p->packet.nmb;
+ struct in_addr owner_ip;
+ struct nmb_name *question = &nmb->question.question_name;
+ BOOL bcast = nmb->header.nm_flags.bcast;
+ uint16 nb_flags = get_nb_flags(nmb->additional->rdata);
+ BOOL group = (nb_flags & NB_GROUP) ? True : False;
+ struct name_record *namerec;
+ int rcode = 0;
+
+ putip((char *)&owner_ip,&nmb->additional->rdata[2]);
+
+ if(!bcast)
+ {
+ /* We should only get broadcast name release packets here.
+ Anyone trying to release unicast should be going to a WINS
+ server. If the code gets here, then either we are not a wins
+ server and they sent it anyway, or we are a WINS server and
+ the request was malformed. Either way, log an error here.
+ and send an error reply back.
+ */
+ DEBUG(0,("process_name_release_request: unicast name release request \
+received for name %s from IP %s on subnet %s. Error - should be sent to WINS server\n",
+ nmb_namestr(question), inet_ntoa(owner_ip), subrec->subnet_name));
+
+ send_name_release_response(FMT_ERR, p);
+ return;
+ }
+
+ DEBUG(3,("process_name_release_request: Name release on name %s, \
+subnet %s from owner IP %s\n",
+ nmb_namestr(&nmb->question.question_name),
+ subrec->subnet_name, inet_ntoa(owner_ip)));
+
+ /* If someone is releasing a broadcast group name, just ignore it. */
+ if( group && !ismyip(owner_ip) )
+ return;
+
+ /*
+ * Code to work around a bug in FTP OnNet software NBT implementation.
+ * They do a broadcast name release for WORKGROUP<0> and WORKGROUP<1e>
+ * names and *don't set the group bit* !!!!!
+ */
+
+ if( !group && !ismyip(owner_ip) && strequal(question->name, lp_workgroup()) &&
+ ((question->name_type == 0x0) || (question->name_type == 0x1e)))
+ {
+ DEBUG(6,("process_name_release_request: FTP OnNet bug workaround. Ignoring \
+group release name %s from IP %s on subnet %s with no group bit set.\n",
+ nmb_namestr(question), inet_ntoa(owner_ip), subrec->subnet_name ));
+ return;
+ }
+
+ namerec = find_name_on_subnet(subrec, &nmb->question.question_name, FIND_ANY_NAME);
+
+ /* We only care about someone trying to release one of our names. */
+ if( namerec
+ && ( (namerec->data.source == SELF_NAME)
+ || (namerec->data.source == PERMANENT_NAME) ) )
+ {
+ rcode = ACT_ERR;
+ DEBUG(0, ("process_name_release_request: Attempt to release name %s from IP %s \
+on subnet %s being rejected as it is one of our names.\n",
+ nmb_namestr(&nmb->question.question_name), inet_ntoa(owner_ip), subrec->subnet_name));
+ }
+
+ if(rcode == 0)
+ return;
+
+ /* Send a NAME RELEASE RESPONSE (pos/neg) see rfc1002.txt 4.2.10-11 */
+ send_name_release_response(rcode, p);
+}
+
+/****************************************************************************
+Send a name registration response.
+**************************************************************************/
+
+static void send_name_registration_response(int rcode, int ttl, struct packet_struct *p)
+{
+ struct nmb_packet *nmb = &p->packet.nmb;
+ char rdata[6];
+
+ memcpy(&rdata[0], &nmb->additional->rdata[0], 6);
+
+ reply_netbios_packet(p, /* Packet to reply to. */
+ rcode, /* Result code. */
+ NMB_REG, /* nmbd type code. */
+ NMB_NAME_REG_OPCODE, /* opcode. */
+ ttl, /* ttl. */
+ rdata, /* data to send. */
+ 6); /* data length. */
+}
+
+/****************************************************************************
+Process a name refresh request on a broadcast subnet.
+**************************************************************************/
+
+void process_name_refresh_request(struct subnet_record *subrec,
+ struct packet_struct *p)
+{
+
+ struct nmb_packet *nmb = &p->packet.nmb;
+ struct nmb_name *question = &nmb->question.question_name;
+ BOOL bcast = nmb->header.nm_flags.bcast;
+ struct in_addr from_ip;
+
+ putip((char *)&from_ip,&nmb->additional->rdata[2]);
+
+ if(!bcast)
+ {
+ /* We should only get broadcast name refresh packets here.
+ Anyone trying to refresh unicast should be going to a WINS
+ server. If the code gets here, then either we are not a wins
+ server and they sent it anyway, or we are a WINS server and
+ the request was malformed. Either way, log an error here.
+ and send an error reply back.
+ */
+ DEBUG(0,("process_name_refresh_request: unicast name registration request \
+received for name %s from IP %s on subnet %s.\n",
+ nmb_namestr(question), inet_ntoa(from_ip), subrec->subnet_name));
+ DEBUG(0,("Error - should be sent to WINS server\n"));
+
+ send_name_registration_response(FMT_ERR, 0, p);
+ return;
+ }
+
+ /* Just log a message. We really don't care about broadcast name
+ refreshes. */
+
+ DEBUG(3,("process_name_refresh_request: Name refresh for name %s \
+IP %s on subnet %s\n", nmb_namestr(question), inet_ntoa(from_ip), subrec->subnet_name));
+
+}
+
+/****************************************************************************
+Process a name registration request on a broadcast subnet.
+**************************************************************************/
+
+void process_name_registration_request(struct subnet_record *subrec,
+ struct packet_struct *p)
+{
+ struct nmb_packet *nmb = &p->packet.nmb;
+ struct nmb_name *question = &nmb->question.question_name;
+ BOOL bcast = nmb->header.nm_flags.bcast;
+ uint16 nb_flags = get_nb_flags(nmb->additional->rdata);
+ BOOL group = (nb_flags & NB_GROUP) ? True : False;
+ struct name_record *namerec = NULL;
+ int ttl = nmb->additional->ttl;
+ struct in_addr from_ip;
+
+ putip((char *)&from_ip,&nmb->additional->rdata[2]);
+
+ if(!bcast)
+ {
+ /* We should only get broadcast name registration packets here.
+ Anyone trying to register unicast should be going to a WINS
+ server. If the code gets here, then either we are not a wins
+ server and they sent it anyway, or we are a WINS server and
+ the request was malformed. Either way, log an error here.
+ and send an error reply back.
+ */
+ DEBUG(0,("process_name_registration_request: unicast name registration request \
+received for name %s from IP %s on subnet %s. Error - should be sent to WINS server\n",
+ nmb_namestr(question), inet_ntoa(from_ip), subrec->subnet_name));
+
+ send_name_registration_response(FMT_ERR, 0, p);
+ return;
+ }
+
+ DEBUG(3,("process_name_registration_request: Name registration for name %s \
+IP %s on subnet %s\n", nmb_namestr(question), inet_ntoa(from_ip), subrec->subnet_name));
+
+ /* See if the name already exists. */
+ namerec = find_name_on_subnet(subrec, question, FIND_ANY_NAME);
+
+ /*
+ * If the name being registered exists and is a WINS_PROXY_NAME
+ * then delete the WINS proxy name entry so we don't reply erroneously
+ * later to queries.
+ */
+
+ if((namerec != NULL) && (namerec->data.source == WINS_PROXY_NAME))
+ {
+ remove_name_from_namelist( subrec, namerec );
+ namerec = NULL;
+ }
+
+ if (!group)
+ {
+ /* Unique name. */
+
+ if( (namerec != NULL)
+ && ( (namerec->data.source == SELF_NAME)
+ || (namerec->data.source == PERMANENT_NAME)
+ || NAME_GROUP(namerec) ) )
+ {
+ /* No-one can register one of Samba's names, nor can they
+ register a name that's a group name as a unique name */
+
+ send_name_registration_response(ACT_ERR, 0, p);
+ return;
+ }
+ else if(namerec != NULL)
+ {
+ /* Update the namelist record with the new information. */
+ namerec->data.ip[0] = from_ip;
+ update_name_ttl(namerec, ttl);
+
+ DEBUG(3,("process_name_registration_request: Updated name record %s \
+with IP %s on subnet %s\n",nmb_namestr(&namerec->name),inet_ntoa(from_ip), subrec->subnet_name));
+ return;
+ }
+ }
+ else
+ {
+ /* Group name. */
+
+ if( (namerec != NULL)
+ && !NAME_GROUP(namerec)
+ && ( (namerec->data.source == SELF_NAME)
+ || (namerec->data.source == PERMANENT_NAME) ) )
+ {
+ /* Disallow group names when we have a unique name. */
+ send_name_registration_response(ACT_ERR, 0, p);
+ return;
+ }
+ }
+}
+
+/****************************************************************************
+This is used to sort names for a name status into a sensible order.
+We put our own names first, then in alphabetical order.
+**************************************************************************/
+
+static int status_compare(char *n1,char *n2)
+{
+ int l1,l2,l3;
+
+ /* It's a bit tricky because the names are space padded */
+ for (l1=0;l1<15 && n1[l1] && n1[l1] != ' ';l1++) ;
+ for (l2=0;l2<15 && n2[l2] && n2[l2] != ' ';l2++) ;
+ l3 = strlen(lp_netbios_name());
+
+ if ((l1==l3) && strncmp(n1,lp_netbios_name(),l3) == 0 &&
+ (l2!=l3 || strncmp(n2,lp_netbios_name(),l3) != 0))
+ return -1;
+
+ if ((l2==l3) && strncmp(n2,lp_netbios_name(),l3) == 0 &&
+ (l1!=l3 || strncmp(n1,lp_netbios_name(),l3) != 0))
+ return 1;
+
+ return memcmp(n1,n2,18);
+}
+
+
+/****************************************************************************
+ Process a node status query
+ ****************************************************************************/
+
+void process_node_status_request(struct subnet_record *subrec, struct packet_struct *p)
+{
+ struct nmb_packet *nmb = &p->packet.nmb;
+ char *qname = nmb->question.question_name.name;
+ int ques_type = nmb->question.question_name.name_type;
+ char rdata[MAX_DGRAM_SIZE];
+ char *countptr, *buf, *bufend, *buf0;
+ int names_added,i;
+ struct name_record *namerec;
+
+ DEBUG(3,("process_node_status_request: status request for name %s from IP %s on \
+subnet %s.\n", nmb_namestr(&nmb->question.question_name), inet_ntoa(p->ip),
+ subrec->subnet_name));
+
+ if((namerec = find_name_on_subnet(subrec, &nmb->question.question_name,
+ FIND_SELF_NAME)) == 0)
+ {
+ DEBUG(1,("process_node_status_request: status request for name %s from IP %s on \
+subnet %s - name not found.\n", nmb_namestr(&nmb->question.question_name),
+ inet_ntoa(p->ip), subrec->subnet_name));
+
+ return;
+ }
+
+ /* this is not an exact calculation. the 46 is for the stats buffer
+ and the 60 is to leave room for the header etc */
+ bufend = &rdata[MAX_DGRAM_SIZE] - (18 + 46 + 60);
+ countptr = buf = rdata;
+ buf += 1;
+ buf0 = buf;
+
+ names_added = 0;
+
+ namerec = (struct name_record *)ubi_trFirst( subrec->namelist );
+
+ while (buf < bufend)
+ {
+ if( (namerec->data.source == SELF_NAME)
+ || (namerec->data.source == PERMANENT_NAME) )
+ {
+ int name_type = namerec->name.name_type;
+
+ if (!strequal(namerec->name.name,"*") &&
+ !strequal(namerec->name.name,"__SAMBA__") &&
+ (name_type < 0x1b || name_type >= 0x20 ||
+ ques_type < 0x1b || ques_type >= 0x20 ||
+ strequal(qname, namerec->name.name)))
+ {
+ /* Start with the name. */
+ memset(buf,'\0',18);
+ slprintf(buf, 17, "%-15.15s",namerec->name.name);
+ strupper(buf);
+
+ /* Put the name type and netbios flags in the buffer. */
+ buf[15] = name_type;
+ set_nb_flags( &buf[16],namerec->data.nb_flags );
+ buf[16] |= NB_ACTIVE; /* all our names are active */
+
+ buf += 18;
+
+ names_added++;
+ }
+ }
+
+ /* Remove duplicate names. */
+ if (names_added > 1) {
+ qsort( buf0, names_added, 18, QSORT_CAST status_compare );
+ }
+
+ for( i=1; i < names_added ; i++ )
+ {
+ if (memcmp(buf0 + 18*i,buf0 + 18*(i-1),16) == 0)
+ {
+ names_added--;
+ if (names_added == i)
+ break;
+ memmove(buf0 + 18*i,buf0 + 18*(i+1),18*(names_added-i));
+ i--;
+ }
+ }
+
+ buf = buf0 + 18*names_added;
+
+ namerec = (struct name_record *)ubi_trNext( namerec );
+
+ if (!namerec)
+ {
+ /* End of the subnet specific name list. Now
+ add the names on the unicast subnet . */
+ struct subnet_record *uni_subrec = unicast_subnet;
+
+ if (uni_subrec != subrec)
+ {
+ subrec = uni_subrec;
+ namerec = (struct name_record *)ubi_trFirst( subrec->namelist );
+ }
+ }
+ if (!namerec)
+ break;
+
+ }
+
+ SCVAL(countptr,0,names_added);
+
+ /* We don't send any stats as they could be used to attack
+ the protocol. */
+ memset(buf,'\0',46);
+
+ buf += 46;
+
+ /* Send a NODE STATUS RESPONSE */
+ reply_netbios_packet(p, /* Packet to reply to. */
+ 0, /* Result code. */
+ NMB_STATUS, /* nmbd type code. */
+ NMB_NAME_QUERY_OPCODE, /* opcode. */
+ 0, /* ttl. */
+ rdata, /* data to send. */
+ PTR_DIFF(buf,rdata)); /* data length. */
+}
+
+
+/***************************************************************************
+Process a name query.
+
+For broadcast name queries:
+
+ - Only reply if the query is for one of YOUR names.
+ - NEVER send a negative response to a broadcast query.
+
+****************************************************************************/
+
+void process_name_query_request(struct subnet_record *subrec, struct packet_struct *p)
+{
+ struct nmb_packet *nmb = &p->packet.nmb;
+ struct nmb_name *question = &nmb->question.question_name;
+ int name_type = question->name_type;
+ BOOL bcast = nmb->header.nm_flags.bcast;
+ int ttl=0;
+ int rcode = 0;
+ char *prdata = NULL;
+ char rdata[6];
+ BOOL success = False;
+ struct name_record *namerec = NULL;
+ int reply_data_len = 0;
+ int i;
+
+ DEBUG(3,("process_name_query_request: Name query from %s on subnet %s for name %s\n",
+ inet_ntoa(p->ip), subrec->subnet_name, nmb_namestr(question)));
+
+ /* Look up the name in the cache - if the request is a broadcast request that
+ came from a subnet we don't know about then search all the broadcast subnets
+ for a match (as we don't know what interface the request came in on). */
+
+ if(subrec == remote_broadcast_subnet)
+ namerec = find_name_for_remote_broadcast_subnet( question, FIND_ANY_NAME);
+ else
+ namerec = find_name_on_subnet(subrec, question, FIND_ANY_NAME);
+
+ /* Check if it is a name that expired */
+ if (namerec &&
+ ((namerec->data.death_time != PERMANENT_TTL) &&
+ (namerec->data.death_time < p->timestamp))) {
+ DEBUG(5,("process_name_query_request: expired name %s\n", nmb_namestr(&namerec->name)));
+ namerec = NULL;
+ }
+
+ if (namerec) {
+ /*
+ * Always respond to unicast queries.
+ * Don't respond to broadcast queries unless the query is for
+ * a name we own, a Primary Domain Controller name, or a WINS_PROXY
+ * name with type 0 or 0x20. WINS_PROXY names are only ever added
+ * into the namelist if we were configured as a WINS proxy.
+ */
+
+ if (!bcast ||
+ (bcast && ((name_type == 0x1b) ||
+ (namerec->data.source == SELF_NAME) ||
+ (namerec->data.source == PERMANENT_NAME) ||
+ ((namerec->data.source == WINS_PROXY_NAME) &&
+ ((name_type == 0) || (name_type == 0x20)))))) {
+ /* The requested name is a directed query, or it's SELF or PERMANENT or WINS_PROXY,
+ or it's a Domain Master type. */
+
+ /*
+ * If this is a WINS_PROXY_NAME, then ceck that none of the IP
+ * addresses we are returning is on the same broadcast subnet
+ * as the requesting packet. If it is then don't reply as the
+ * actual machine will be replying also and we don't want two
+ * replies to a broadcast query.
+ */
+
+ if (namerec->data.source == WINS_PROXY_NAME) {
+ for( i = 0; i < namerec->data.num_ips; i++) {
+ if (same_net(namerec->data.ip[i], subrec->myip, subrec->mask_ip)) {
+ DEBUG(5,("process_name_query_request: name %s is a WINS proxy name and is also on the same subnet (%s) as the requestor. Not replying.\n",
+ nmb_namestr(&namerec->name), subrec->subnet_name ));
+ return;
+ }
+ }
+ }
+
+ ttl = (namerec->data.death_time != PERMANENT_TTL) ?
+ namerec->data.death_time - p->timestamp : lp_max_ttl();
+
+ /* Copy all known ip addresses into the return data. */
+ /* Optimise for the common case of one IP address so
+ we don't need a malloc. */
+
+ if (namerec->data.num_ips == 1) {
+ prdata = rdata;
+ } else {
+ if ((prdata = (char *)malloc( namerec->data.num_ips * 6 )) == NULL) {
+ DEBUG(0,("process_name_query_request: malloc fail !\n"));
+ return;
+ }
+ }
+
+ for (i = 0; i < namerec->data.num_ips; i++) {
+ set_nb_flags(&prdata[i*6],namerec->data.nb_flags);
+ putip((char *)&prdata[2+(i*6)], &namerec->data.ip[i]);
+ }
+
+ sort_query_replies(prdata, i, p->ip);
+
+ reply_data_len = namerec->data.num_ips * 6;
+ success = True;
+ }
+ }
+
+ /*
+ * If a machine is broadcasting a name lookup request and we have lp_wins_proxy()
+ * set we should initiate a WINS query here. On success we add the resolved name
+ * into our namelist with a type of WINS_PROXY_NAME and then reply to the query.
+ */
+
+ if(!success && (namerec == NULL) && we_are_a_wins_client() && lp_wins_proxy() &&
+ bcast && (subrec != remote_broadcast_subnet)) {
+ make_wins_proxy_name_query_request( subrec, p, question );
+ return;
+ }
+
+ if (!success && bcast) {
+ if(prdata != rdata)
+ SAFE_FREE(prdata);
+ return; /* Never reply with a negative response to broadcasts. */
+ }
+
+ /*
+ * Final check. From observation, if a unicast packet is sent
+ * to a non-WINS server with the recursion desired bit set
+ * then never send a negative response.
+ */
+
+ if(!success && !bcast && nmb->header.nm_flags.recursion_desired) {
+ if(prdata != rdata)
+ SAFE_FREE(prdata);
+ return;
+ }
+
+ if (success) {
+ rcode = 0;
+ DEBUG(3,("OK\n"));
+ } else {
+ rcode = NAM_ERR;
+ DEBUG(3,("UNKNOWN\n"));
+ }
+
+ /* See rfc1002.txt 4.2.13. */
+
+ reply_netbios_packet(p, /* Packet to reply to. */
+ rcode, /* Result code. */
+ NMB_QUERY, /* nmbd type code. */
+ NMB_NAME_QUERY_OPCODE, /* opcode. */
+ ttl, /* ttl. */
+ prdata, /* data to send. */
+ reply_data_len); /* data length. */
+
+ if(prdata != rdata)
+ SAFE_FREE(prdata);
+}