r2: import HEAD into svn+ssh://svn.samba.org/home/svn/samba/trunk

metze

1 files changed, 1343 insertions, 0 deletions

diff --git a/source/libsmb/nmblib.c b/source/libsmb/nmblib.c
new file mode 100644
index 00000000000..3c25eba744f
--- /dev/null
+++ b/source/libsmb/nmblib.c
@@ -0,0 +1,1343 @@
+/* 
+   Unix SMB/CIFS implementation.
+   NBT netbios library routines
+   Copyright (C) Andrew Tridgell 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.
+   
+*/
+
+#include "includes.h"
+
+int num_good_sends = 0;
+int num_good_receives = 0;
+
+static const struct opcode_names {
+	const char *nmb_opcode_name;
+	int opcode;
+} nmb_header_opcode_names[] = {
+	{"Query",           0 },
+	{"Registration",      5 },
+	{"Release",           6 },
+	{"WACK",              7 },
+	{"Refresh",           8 },
+	{"Refresh(altcode)",  9 },
+	{"Multi-homed Registration", 15 },
+	{0, -1 }
+};
+
+/****************************************************************************
+ Lookup a nmb opcode name.
+****************************************************************************/
+
+static const char *lookup_opcode_name( int opcode )
+{
+	const struct opcode_names *op_namep;
+	int i;
+
+	for(i = 0; nmb_header_opcode_names[i].nmb_opcode_name != 0; i++) {
+		op_namep = &nmb_header_opcode_names[i];
+		if(opcode == op_namep->opcode)
+			return op_namep->nmb_opcode_name;
+	}
+	return "<unknown opcode>";
+}
+
+/****************************************************************************
+ Print out a res_rec structure.
+****************************************************************************/
+
+static void debug_nmb_res_rec(struct res_rec *res, const char *hdr)
+{
+	int i, j;
+
+	DEBUGADD( 4, ( "    %s: nmb_name=%s rr_type=%d rr_class=%d ttl=%d\n",
+		hdr,
+		nmb_namestr(&res->rr_name),
+		res->rr_type,
+		res->rr_class,
+		res->ttl ) );
+
+	if( res->rdlength == 0 || res->rdata == NULL )
+		return;
+
+	for (i = 0; i < res->rdlength; i+= MAX_NETBIOSNAME_LEN) {
+		DEBUGADD(4, ("    %s %3x char ", hdr, i));
+
+		for (j = 0; j < MAX_NETBIOSNAME_LEN; j++) {
+			unsigned char x = res->rdata[i+j];
+			if (x < 32 || x > 127)
+				x = '.';
+	  
+			if (i+j >= res->rdlength)
+				break;
+			DEBUGADD(4, ("%c", x));
+		}
+      
+		DEBUGADD(4, ("   hex "));
+
+		for (j = 0; j < MAX_NETBIOSNAME_LEN; j++) {
+			if (i+j >= res->rdlength)
+				break;
+			DEBUGADD(4, ("%02X", (unsigned char)res->rdata[i+j]));
+		}
+      
+		DEBUGADD(4, ("\n"));
+	}
+}
+
+/****************************************************************************
+ Process a nmb packet.
+****************************************************************************/
+
+void debug_nmb_packet(struct packet_struct *p)
+{
+	struct nmb_packet *nmb = &p->packet.nmb;
+
+	if( DEBUGLVL( 4 ) ) {
+		dbgtext( "nmb packet from %s(%d) header: id=%d opcode=%s(%d) response=%s\n",
+			inet_ntoa(p->ip), p->port,
+			nmb->header.name_trn_id,
+			lookup_opcode_name(nmb->header.opcode),
+			nmb->header.opcode,
+			BOOLSTR(nmb->header.response) );
+		dbgtext( "    header: flags: bcast=%s rec_avail=%s rec_des=%s trunc=%s auth=%s\n",
+			BOOLSTR(nmb->header.nm_flags.bcast),
+			BOOLSTR(nmb->header.nm_flags.recursion_available),
+			BOOLSTR(nmb->header.nm_flags.recursion_desired),
+			BOOLSTR(nmb->header.nm_flags.trunc),
+			BOOLSTR(nmb->header.nm_flags.authoritative) );
+		dbgtext( "    header: rcode=%d qdcount=%d ancount=%d nscount=%d arcount=%d\n",
+			nmb->header.rcode,
+			nmb->header.qdcount,
+			nmb->header.ancount,
+			nmb->header.nscount,
+			nmb->header.arcount );
+	}
+
+	if (nmb->header.qdcount) {
+		DEBUGADD( 4, ( "    question: q_name=%s q_type=%d q_class=%d\n",
+			nmb_namestr(&nmb->question.question_name),
+			nmb->question.question_type,
+			nmb->question.question_class) );
+	}
+
+	if (nmb->answers && nmb->header.ancount) {
+		debug_nmb_res_rec(nmb->answers,"answers");
+	}
+	if (nmb->nsrecs && nmb->header.nscount) {
+		debug_nmb_res_rec(nmb->nsrecs,"nsrecs");
+	}
+	if (nmb->additional && nmb->header.arcount) {
+		debug_nmb_res_rec(nmb->additional,"additional");
+	}
+}
+
+/*******************************************************************
+ Handle "compressed" name pointers.
+******************************************************************/
+
+static BOOL handle_name_ptrs(unsigned char *ubuf,int *offset,int length,
+			     BOOL *got_pointer,int *ret)
+{
+	int loop_count=0;
+  
+	while ((ubuf[*offset] & 0xC0) == 0xC0) {
+		if (!*got_pointer)
+			(*ret) += 2;
+		(*got_pointer)=True;
+		(*offset) = ((ubuf[*offset] & ~0xC0)<<8) | ubuf[(*offset)+1];
+		if (loop_count++ == 10 || (*offset) < 0 || (*offset)>(length-2)) {
+			return(False);
+		}
+	}
+	return(True);
+}
+
+/*******************************************************************
+ Parse a nmb name from "compressed" format to something readable
+ return the space taken by the name, or 0 if the name is invalid
+******************************************************************/
+
+static int parse_nmb_name(char *inbuf,int ofs,int length, struct nmb_name *name)
+{
+	int m,n=0;
+	unsigned char *ubuf = (unsigned char *)inbuf;
+	int ret = 0;
+	BOOL got_pointer=False;
+	int loop_count=0;
+	int offset = ofs;
+
+	if (length - offset < 2)
+		return(0);  
+
+	/* handle initial name pointers */
+	if (!handle_name_ptrs(ubuf,&offset,length,&got_pointer,&ret))
+		return(0);
+  
+	m = ubuf[offset];
+
+	if (!m)
+		return(0);
+	if ((m & 0xC0) || offset+m+2 > length)
+		return(0);
+
+	memset((char *)name,'\0',sizeof(*name));
+
+	/* the "compressed" part */
+	if (!got_pointer)
+		ret += m + 2;
+	offset++;
+	while (m > 0) {
+		unsigned char c1,c2;
+		c1 = ubuf[offset++]-'A';
+		c2 = ubuf[offset++]-'A';
+		if ((c1 & 0xF0) || (c2 & 0xF0) || (n > sizeof(name->name)-1))
+			return(0);
+		name->name[n++] = (c1<<4) | c2;
+		m -= 2;
+	}
+	name->name[n] = 0;
+
+	if (n==MAX_NETBIOSNAME_LEN) {
+		/* parse out the name type, its always in the 16th byte of the name */
+		name->name_type = ((unsigned char)name->name[15]) & 0xff;
+  
+		/* remove trailing spaces */
+		name->name[15] = 0;
+		n = 14;
+		while (n && name->name[n]==' ')
+			name->name[n--] = 0;  
+	}
+
+	/* now the domain parts (if any) */
+	n = 0;
+	while (ubuf[offset]) {
+		/* we can have pointers within the domain part as well */
+		if (!handle_name_ptrs(ubuf,&offset,length,&got_pointer,&ret))
+			return(0);
+
+		m = ubuf[offset];
+		/*
+		 * Don't allow null domain parts.
+		 */
+		if (!m)
+			return(0);
+		if (!got_pointer)
+			ret += m+1;
+		if (n)
+			name->scope[n++] = '.';
+		if (m+2+offset>length || n+m+1>sizeof(name->scope))
+			return(0);
+		offset++;
+		while (m--)
+			name->scope[n++] = (char)ubuf[offset++];
+
+		/*
+		 * Watch for malicious loops.
+		 */
+		if (loop_count++ == 10)
+			return 0;
+	}
+	name->scope[n++] = 0;  
+
+	return(ret);
+}
+
+/****************************************************************************
+ Put a netbios name, padding(s) and a name type into a 16 character buffer.
+ name is already in DOS charset.
+ [15 bytes name + padding][1 byte name type].
+****************************************************************************/
+
+static void put_name(char *dest, const char *name, int pad, unsigned int name_type)
+{
+	size_t len = strlen(name);
+
+	memcpy(dest, name, (len < MAX_NETBIOSNAME_LEN) ? len : MAX_NETBIOSNAME_LEN - 1);
+	if (len < MAX_NETBIOSNAME_LEN - 1) {
+		memset(dest + len, pad, MAX_NETBIOSNAME_LEN - 1 - len);
+	}
+	dest[MAX_NETBIOSNAME_LEN - 1] = name_type;
+}
+
+/*******************************************************************
+ Put a compressed nmb name into a buffer. Return the length of the
+ compressed name.
+
+ Compressed names are really weird. The "compression" doubles the
+ size. The idea is that it also means that compressed names conform
+ to the doman name system. See RFC1002.
+******************************************************************/
+
+static int put_nmb_name(char *buf,int offset,struct nmb_name *name)
+{
+	int ret,m;
+	nstring buf1;
+	char *p;
+
+	if (strcmp(name->name,"*") == 0) {
+		/* special case for wildcard name */
+		put_name(buf1, "*", '\0', name->name_type);
+	} else {
+		put_name(buf1, name->name, ' ', name->name_type);
+	}
+
+	buf[offset] = 0x20;
+
+	ret = 34;
+
+	for (m=0;m<MAX_NETBIOSNAME_LEN;m++) {
+		buf[offset+1+2*m] = 'A' + ((buf1[m]>>4)&0xF);
+		buf[offset+2+2*m] = 'A' + (buf1[m]&0xF);
+	}
+	offset += 33;
+
+	buf[offset] = 0;
+
+	if (name->scope[0]) {
+		/* XXXX this scope handling needs testing */
+		ret += strlen(name->scope) + 1;
+		safe_strcpy(&buf[offset+1],name->scope,sizeof(name->scope));  
+  
+		p = &buf[offset+1];
+		while ((p = strchr_m(p,'.'))) {
+			buf[offset] = PTR_DIFF(p,&buf[offset+1]);
+			offset += (buf[offset] + 1);
+			p = &buf[offset+1];
+		}
+		buf[offset] = strlen(&buf[offset+1]);
+	}
+
+	return(ret);
+}
+
+/*******************************************************************
+ Useful for debugging messages.
+******************************************************************/
+
+char *nmb_namestr(struct nmb_name *n)
+{
+	static int i=0;
+	static fstring ret[4];
+	fstring name;
+	char *p = ret[i];
+
+	pull_ascii_fstring(name, n->name);
+	if (!n->scope[0])
+		slprintf(p,sizeof(fstring)-1, "%s<%02x>",name,n->name_type);
+	else
+		slprintf(p,sizeof(fstring)-1, "%s<%02x>.%s",name,n->name_type,n->scope);
+
+	i = (i+1)%4;
+	return(p);
+}
+
+/*******************************************************************
+ Allocate and parse some resource records.
+******************************************************************/
+
+static BOOL parse_alloc_res_rec(char *inbuf,int *offset,int length,
+				struct res_rec **recs, int count)
+{
+	int i;
+
+	*recs = (struct res_rec *)malloc(sizeof(**recs)*count);
+	if (!*recs)
+		return(False);
+
+	memset((char *)*recs,'\0',sizeof(**recs)*count);
+
+	for (i=0;i<count;i++) {
+		int l = parse_nmb_name(inbuf,*offset,length,&(*recs)[i].rr_name);
+		(*offset) += l;
+		if (!l || (*offset)+10 > length) {
+			SAFE_FREE(*recs);
+			return(False);
+		}
+		(*recs)[i].rr_type = RSVAL(inbuf,(*offset));
+		(*recs)[i].rr_class = RSVAL(inbuf,(*offset)+2);
+		(*recs)[i].ttl = RIVAL(inbuf,(*offset)+4);
+		(*recs)[i].rdlength = RSVAL(inbuf,(*offset)+8);
+		(*offset) += 10;
+		if ((*recs)[i].rdlength>sizeof((*recs)[i].rdata) || 
+				(*offset)+(*recs)[i].rdlength > length) {
+			SAFE_FREE(*recs);
+			return(False);
+		}
+		memcpy((*recs)[i].rdata,inbuf+(*offset),(*recs)[i].rdlength);
+		(*offset) += (*recs)[i].rdlength;    
+	}
+	return(True);
+}
+
+/*******************************************************************
+ Put a resource record into a packet.
+******************************************************************/
+
+static int put_res_rec(char *buf,int offset,struct res_rec *recs,int count)
+{
+	int ret=0;
+	int i;
+
+	for (i=0;i<count;i++) {
+		int l = put_nmb_name(buf,offset,&recs[i].rr_name);
+		offset += l;
+		ret += l;
+		RSSVAL(buf,offset,recs[i].rr_type);
+		RSSVAL(buf,offset+2,recs[i].rr_class);
+		RSIVAL(buf,offset+4,recs[i].ttl);
+		RSSVAL(buf,offset+8,recs[i].rdlength);
+		memcpy(buf+offset+10,recs[i].rdata,recs[i].rdlength);
+		offset += 10+recs[i].rdlength;
+		ret += 10+recs[i].rdlength;
+	}
+
+	return(ret);
+}
+
+/*******************************************************************
+ Put a compressed name pointer record into a packet.
+******************************************************************/
+
+static int put_compressed_name_ptr(unsigned char *buf,int offset,struct res_rec *rec,int ptr_offset)
+{  
+	int ret=0;
+	buf[offset] = (0xC0 | ((ptr_offset >> 8) & 0xFF));
+	buf[offset+1] = (ptr_offset & 0xFF);
+	offset += 2;
+	ret += 2;
+	RSSVAL(buf,offset,rec->rr_type);
+	RSSVAL(buf,offset+2,rec->rr_class);
+	RSIVAL(buf,offset+4,rec->ttl);
+	RSSVAL(buf,offset+8,rec->rdlength);
+	memcpy(buf+offset+10,rec->rdata,rec->rdlength);
+	offset += 10+rec->rdlength;
+	ret += 10+rec->rdlength;
+    
+	return(ret);
+}
+
+/*******************************************************************
+ Parse a dgram packet. Return False if the packet can't be parsed 
+ or is invalid for some reason, True otherwise.
+
+ This is documented in section 4.4.1 of RFC1002.
+******************************************************************/
+
+static BOOL parse_dgram(char *inbuf,int length,struct dgram_packet *dgram)
+{
+	int offset;
+	int flags;
+
+	memset((char *)dgram,'\0',sizeof(*dgram));
+
+	if (length < 14)
+		return(False);
+
+	dgram->header.msg_type = CVAL(inbuf,0);
+	flags = CVAL(inbuf,1);
+	dgram->header.flags.node_type = (enum node_type)((flags>>2)&3);
+	if (flags & 1)
+		dgram->header.flags.more = True;
+	if (flags & 2)
+		dgram->header.flags.first = True;
+	dgram->header.dgm_id = RSVAL(inbuf,2);
+	putip((char *)&dgram->header.source_ip,inbuf+4);
+	dgram->header.source_port = RSVAL(inbuf,8);
+	dgram->header.dgm_length = RSVAL(inbuf,10);
+	dgram->header.packet_offset = RSVAL(inbuf,12);
+
+	offset = 14;
+
+	if (dgram->header.msg_type == 0x10 ||
+			dgram->header.msg_type == 0x11 ||
+			dgram->header.msg_type == 0x12) {      
+		offset += parse_nmb_name(inbuf,offset,length,&dgram->source_name);
+		offset += parse_nmb_name(inbuf,offset,length,&dgram->dest_name);
+	}
+
+	if (offset >= length || (length-offset > sizeof(dgram->data))) 
+		return(False);
+
+	dgram->datasize = length-offset;
+	memcpy(dgram->data,inbuf+offset,dgram->datasize);
+
+	return(True);
+}
+
+/*******************************************************************
+ Parse a nmb packet. Return False if the packet can't be parsed 
+ or is invalid for some reason, True otherwise.
+******************************************************************/
+
+static BOOL parse_nmb(char *inbuf,int length,struct nmb_packet *nmb)
+{
+	int nm_flags,offset;
+
+	memset((char *)nmb,'\0',sizeof(*nmb));
+
+	if (length < 12)
+		return(False);
+
+	/* parse the header */
+	nmb->header.name_trn_id = RSVAL(inbuf,0);
+
+	DEBUG(10,("parse_nmb: packet id = %d\n", nmb->header.name_trn_id));
+
+	nmb->header.opcode = (CVAL(inbuf,2) >> 3) & 0xF;
+	nmb->header.response = ((CVAL(inbuf,2)>>7)&1)?True:False;
+	nm_flags = ((CVAL(inbuf,2) & 0x7) << 4) + (CVAL(inbuf,3)>>4);
+	nmb->header.nm_flags.bcast = (nm_flags&1)?True:False;
+	nmb->header.nm_flags.recursion_available = (nm_flags&8)?True:False;
+	nmb->header.nm_flags.recursion_desired = (nm_flags&0x10)?True:False;
+	nmb->header.nm_flags.trunc = (nm_flags&0x20)?True:False;
+	nmb->header.nm_flags.authoritative = (nm_flags&0x40)?True:False;  
+	nmb->header.rcode = CVAL(inbuf,3) & 0xF;
+	nmb->header.qdcount = RSVAL(inbuf,4);
+	nmb->header.ancount = RSVAL(inbuf,6);
+	nmb->header.nscount = RSVAL(inbuf,8);
+	nmb->header.arcount = RSVAL(inbuf,10);
+  
+	if (nmb->header.qdcount) {
+		offset = parse_nmb_name(inbuf,12,length,&nmb->question.question_name);
+		if (!offset)
+			return(False);
+
+		if (length - (12+offset) < 4)
+			return(False);
+		nmb->question.question_type = RSVAL(inbuf,12+offset);
+		nmb->question.question_class = RSVAL(inbuf,12+offset+2);
+
+		offset += 12+4;
+	} else {
+		offset = 12;
+	}
+
+	/* and any resource records */
+	if (nmb->header.ancount && !parse_alloc_res_rec(inbuf,&offset,length,&nmb->answers,
+					nmb->header.ancount))
+		return(False);
+
+	if (nmb->header.nscount && !parse_alloc_res_rec(inbuf,&offset,length,&nmb->nsrecs,
+					nmb->header.nscount))
+		return(False);
+  
+	if (nmb->header.arcount && !parse_alloc_res_rec(inbuf,&offset,length,&nmb->additional,
+					nmb->header.arcount))
+		return(False);
+
+	return(True);
+}
+
+/*******************************************************************
+ 'Copy constructor' for an nmb packet.
+******************************************************************/
+
+static struct packet_struct *copy_nmb_packet(struct packet_struct *packet)
+{  
+	struct nmb_packet *nmb;
+	struct nmb_packet *copy_nmb;
+	struct packet_struct *pkt_copy;
+
+	if(( pkt_copy = (struct packet_struct *)malloc(sizeof(*packet))) == NULL) {
+		DEBUG(0,("copy_nmb_packet: malloc fail.\n"));
+		return NULL;
+	}
+
+	/* Structure copy of entire thing. */
+
+	*pkt_copy = *packet;
+
+	/* Ensure this copy is not locked. */
+	pkt_copy->locked = False;
+
+	/* Ensure this copy has no resource records. */
+	nmb = &packet->packet.nmb;
+	copy_nmb = &pkt_copy->packet.nmb;
+
+	copy_nmb->answers = NULL;
+	copy_nmb->nsrecs = NULL;
+	copy_nmb->additional = NULL;
+
+	/* Now copy any resource records. */
+
+	if (nmb->answers) {
+		if((copy_nmb->answers = (struct res_rec *)
+					malloc(nmb->header.ancount * sizeof(struct res_rec))) == NULL)
+			goto free_and_exit;
+		memcpy((char *)copy_nmb->answers, (char *)nmb->answers, 
+				nmb->header.ancount * sizeof(struct res_rec));
+	}
+	if (nmb->nsrecs) {
+		if((copy_nmb->nsrecs = (struct res_rec *)
+					malloc(nmb->header.nscount * sizeof(struct res_rec))) == NULL)
+			goto free_and_exit;
+		memcpy((char *)copy_nmb->nsrecs, (char *)nmb->nsrecs, 
+				nmb->header.nscount * sizeof(struct res_rec));
+	}
+	if (nmb->additional) {
+		if((copy_nmb->additional = (struct res_rec *)
+					malloc(nmb->header.arcount * sizeof(struct res_rec))) == NULL)
+			goto free_and_exit;
+		memcpy((char *)copy_nmb->additional, (char *)nmb->additional, 
+				nmb->header.arcount * sizeof(struct res_rec));
+	}
+
+	return pkt_copy;
+
+ free_and_exit:
+
+	SAFE_FREE(copy_nmb->answers);
+	SAFE_FREE(copy_nmb->nsrecs);
+	SAFE_FREE(copy_nmb->additional);
+	SAFE_FREE(pkt_copy);
+
+	DEBUG(0,("copy_nmb_packet: malloc fail in resource records.\n"));
+	return NULL;
+}
+
+/*******************************************************************
+  'Copy constructor' for a dgram packet.
+******************************************************************/
+
+static struct packet_struct *copy_dgram_packet(struct packet_struct *packet)
+{ 
+	struct packet_struct *pkt_copy;
+
+	if(( pkt_copy = (struct packet_struct *)malloc(sizeof(*packet))) == NULL) {
+		DEBUG(0,("copy_dgram_packet: malloc fail.\n"));
+		return NULL;
+	}
+
+	/* Structure copy of entire thing. */
+
+	*pkt_copy = *packet;
+
+	/* Ensure this copy is not locked. */
+	pkt_copy->locked = False;
+
+	/* There are no additional pointers in a dgram packet,
+		we are finished. */
+	return pkt_copy;
+}
+
+/*******************************************************************
+ 'Copy constructor' for a generic packet.
+******************************************************************/
+
+struct packet_struct *copy_packet(struct packet_struct *packet)
+{  
+	if(packet->packet_type == NMB_PACKET)
+		return copy_nmb_packet(packet);
+	else if (packet->packet_type == DGRAM_PACKET)
+		return copy_dgram_packet(packet);
+	return NULL;
+}
+ 
+/*******************************************************************
+ Free up any resources associated with an nmb packet.
+******************************************************************/
+
+static void free_nmb_packet(struct nmb_packet *nmb)
+{  
+	SAFE_FREE(nmb->answers);
+	SAFE_FREE(nmb->nsrecs);
+	SAFE_FREE(nmb->additional);
+}
+
+/*******************************************************************
+ Free up any resources associated with a dgram packet.
+******************************************************************/
+
+static void free_dgram_packet(struct dgram_packet *nmb)
+{  
+	/* We have nothing to do for a dgram packet. */
+}
+
+/*******************************************************************
+ Free up any resources associated with a packet.
+******************************************************************/
+
+void free_packet(struct packet_struct *packet)
+{  
+	if (packet->locked) 
+		return;
+	if (packet->packet_type == NMB_PACKET)
+		free_nmb_packet(&packet->packet.nmb);
+	else if (packet->packet_type == DGRAM_PACKET)
+		free_dgram_packet(&packet->packet.dgram);
+	ZERO_STRUCTPN(packet);
+	SAFE_FREE(packet);
+}
+
+/*******************************************************************
+ Parse a packet buffer into a packet structure.
+******************************************************************/
+
+struct packet_struct *parse_packet(char *buf,int length,
+				   enum packet_type packet_type)
+{
+	extern struct in_addr lastip;
+	extern int lastport;
+	struct packet_struct *p;
+	BOOL ok=False;
+
+	p = (struct packet_struct *)malloc(sizeof(*p));
+	if (!p)
+		return(NULL);
+
+	p->next = NULL;
+	p->prev = NULL;
+	p->ip = lastip;
+	p->port = lastport;
+	p->locked = False;
+	p->timestamp = time(NULL);
+	p->packet_type = packet_type;
+
+	switch (packet_type) {
+	case NMB_PACKET:
+		ok = parse_nmb(buf,length,&p->packet.nmb);
+		break;
+		
+	case DGRAM_PACKET:
+		ok = parse_dgram(buf,length,&p->packet.dgram);
+		break;
+	}
+
+	if (!ok) {
+		free_packet(p);
+		return NULL;
+	}
+
+	return p;
+}
+
+/*******************************************************************
+ Read a packet from a socket and parse it, returning a packet ready
+ to be used or put on the queue. This assumes a UDP socket.
+******************************************************************/
+
+struct packet_struct *read_packet(int fd,enum packet_type packet_type)
+{
+	struct packet_struct *packet;
+	char buf[MAX_DGRAM_SIZE];
+	int length;
+	
+	length = read_udp_socket(fd,buf,sizeof(buf));
+	if (length < MIN_DGRAM_SIZE)
+		return(NULL);
+	
+	packet = parse_packet(buf, length, packet_type);
+	if (!packet)
+		return NULL;
+
+	packet->fd = fd;
+	
+	num_good_receives++;
+	
+	DEBUG(5,("Received a packet of len %d from (%s) port %d\n",
+		 length, inet_ntoa(packet->ip), packet->port ) );
+	
+	return(packet);
+}
+					 
+/*******************************************************************
+ Send a udp packet on a already open socket.
+******************************************************************/
+
+static BOOL send_udp(int fd,char *buf,int len,struct in_addr ip,int port)
+{
+	BOOL ret = False;
+	int i;
+	struct sockaddr_in sock_out;
+
+	/* set the address and port */
+	memset((char *)&sock_out,'\0',sizeof(sock_out));
+	putip((char *)&sock_out.sin_addr,(char *)&ip);
+	sock_out.sin_port = htons( port );
+	sock_out.sin_family = AF_INET;
+  
+	DEBUG( 5, ( "Sending a packet of len %d to (%s) on port %d\n",
+			len, inet_ntoa(ip), port ) );
+
+	/*
+	 * Patch to fix asynch error notifications from Linux kernel.
+	 */
+	
+	for (i = 0; i < 5; i++) {
+		ret = (sendto(fd,buf,len,0,(struct sockaddr *)&sock_out, sizeof(sock_out)) >= 0);
+		if (ret || errno != ECONNREFUSED)
+			break;
+	}
+
+	if (!ret)
+		DEBUG(0,("Packet send failed to %s(%d) ERRNO=%s\n",
+			inet_ntoa(ip),port,strerror(errno)));
+
+	if (ret)
+		num_good_sends++;
+
+	return(ret);
+}
+
+/*******************************************************************
+ Build a dgram packet ready for sending.
+
+ XXXX This currently doesn't handle packets too big for one
+ datagram. It should split them and use the packet_offset, more and
+ first flags to handle the fragmentation. Yuck.
+
+   [...but it isn't clear that we would ever need to send a
+   a fragmented NBT Datagram.  The IP layer does its own
+   fragmentation to ensure that messages can fit into the path
+   MTU.  It *is* important to be able to receive and rebuild
+   fragmented NBT datagrams, just in case someone out there
+   really has implemented this 'feature'.  crh -)------ ]
+
+******************************************************************/
+
+static int build_dgram(char *buf,struct packet_struct *p)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	unsigned char *ubuf = (unsigned char *)buf;
+	int offset=0;
+
+	/* put in the header */
+	ubuf[0] = dgram->header.msg_type;
+	ubuf[1] = (((int)dgram->header.flags.node_type)<<2);
+	if (dgram->header.flags.more)
+		ubuf[1] |= 1;
+	if (dgram->header.flags.first)
+		ubuf[1] |= 2;
+	RSSVAL(ubuf,2,dgram->header.dgm_id);
+	putip(ubuf+4,(char *)&dgram->header.source_ip);
+	RSSVAL(ubuf,8,dgram->header.source_port);
+	RSSVAL(ubuf,12,dgram->header.packet_offset);
+
+	offset = 14;
+
+	if (dgram->header.msg_type == 0x10 ||
+			dgram->header.msg_type == 0x11 ||
+			dgram->header.msg_type == 0x12) {      
+		offset += put_nmb_name((char *)ubuf,offset,&dgram->source_name);
+		offset += put_nmb_name((char *)ubuf,offset,&dgram->dest_name);
+	}
+
+	memcpy(ubuf+offset,dgram->data,dgram->datasize);
+	offset += dgram->datasize;
+
+	/* automatically set the dgm_length
+	 * NOTE: RFC1002 says the dgm_length does *not*
+	 *       include the fourteen-byte header. crh
+	 */
+	dgram->header.dgm_length = (offset - 14);
+	RSSVAL(ubuf,10,dgram->header.dgm_length); 
+
+	return(offset);
+}
+
+/*******************************************************************
+ Build a nmb name
+*******************************************************************/
+
+void make_nmb_name( struct nmb_name *n, const char *name, int type)
+{
+	fstring unix_name;
+	memset( (char *)n, '\0', sizeof(struct nmb_name) );
+	fstrcpy(unix_name, name);
+	strupper_m(unix_name);
+	push_ascii(n->name, unix_name, sizeof(n->name), STR_TERMINATE);
+	n->name_type = (unsigned int)type & 0xFF;
+	push_ascii(n->scope,  global_scope(), 64, STR_TERMINATE);
+}
+
+/*******************************************************************
+  Compare two nmb names
+******************************************************************/
+
+BOOL nmb_name_equal(struct nmb_name *n1, struct nmb_name *n2)
+{
+	return ((n1->name_type == n2->name_type) &&
+		strequal(n1->name ,n2->name ) &&
+		strequal(n1->scope,n2->scope));
+}
+
+/*******************************************************************
+ Build a nmb packet ready for sending.
+
+ XXXX this currently relies on not being passed something that expands
+ to a packet too big for the buffer. Eventually this should be
+ changed to set the trunc bit so the receiver can request the rest
+ via tcp (when that becomes supported)
+******************************************************************/
+
+static int build_nmb(char *buf,struct packet_struct *p)
+{
+	struct nmb_packet *nmb = &p->packet.nmb;
+	unsigned char *ubuf = (unsigned char *)buf;
+	int offset=0;
+
+	/* put in the header */
+	RSSVAL(ubuf,offset,nmb->header.name_trn_id);
+	ubuf[offset+2] = (nmb->header.opcode & 0xF) << 3;
+	if (nmb->header.response)
+		ubuf[offset+2] |= (1<<7);
+	if (nmb->header.nm_flags.authoritative && 
+			nmb->header.response)
+		ubuf[offset+2] |= 0x4;
+	if (nmb->header.nm_flags.trunc)
+		ubuf[offset+2] |= 0x2;
+	if (nmb->header.nm_flags.recursion_desired)
+		ubuf[offset+2] |= 0x1;
+	if (nmb->header.nm_flags.recursion_available &&
+			nmb->header.response)
+		ubuf[offset+3] |= 0x80;
+	if (nmb->header.nm_flags.bcast)
+		ubuf[offset+3] |= 0x10;
+	ubuf[offset+3] |= (nmb->header.rcode & 0xF);
+
+	RSSVAL(ubuf,offset+4,nmb->header.qdcount);
+	RSSVAL(ubuf,offset+6,nmb->header.ancount);
+	RSSVAL(ubuf,offset+8,nmb->header.nscount);
+	RSSVAL(ubuf,offset+10,nmb->header.arcount);
+  
+	offset += 12;
+	if (nmb->header.qdcount) {
+		/* XXXX this doesn't handle a qdcount of > 1 */
+		offset += put_nmb_name((char *)ubuf,offset,&nmb->question.question_name);
+		RSSVAL(ubuf,offset,nmb->question.question_type);
+		RSSVAL(ubuf,offset+2,nmb->question.question_class);
+		offset += 4;
+	}
+
+	if (nmb->header.ancount)
+		offset += put_res_rec((char *)ubuf,offset,nmb->answers,
+				nmb->header.ancount);
+
+	if (nmb->header.nscount)
+		offset += put_res_rec((char *)ubuf,offset,nmb->nsrecs,
+				nmb->header.nscount);
+
+	/*
+	 * The spec says we must put compressed name pointers
+	 * in the following outgoing packets :
+	 * NAME_REGISTRATION_REQUEST, NAME_REFRESH_REQUEST,
+	 * NAME_RELEASE_REQUEST.
+	 */
+
+	if((nmb->header.response == False) &&
+			((nmb->header.opcode == NMB_NAME_REG_OPCODE) ||
+			(nmb->header.opcode == NMB_NAME_RELEASE_OPCODE) ||
+			(nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_8) ||
+			(nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_9) ||
+			(nmb->header.opcode == NMB_NAME_MULTIHOMED_REG_OPCODE)) &&
+			(nmb->header.arcount == 1)) {
+
+		offset += put_compressed_name_ptr(ubuf,offset,nmb->additional,12);
+
+	} else if (nmb->header.arcount) {
+		offset += put_res_rec((char *)ubuf,offset,nmb->additional,
+			nmb->header.arcount);  
+	}
+	return(offset);
+}
+
+/*******************************************************************
+ Linearise a packet.
+******************************************************************/
+
+int build_packet(char *buf, struct packet_struct *p)
+{
+	int len = 0;
+
+	switch (p->packet_type) {
+	case NMB_PACKET:
+		len = build_nmb(buf,p);
+		break;
+
+	case DGRAM_PACKET:
+		len = build_dgram(buf,p);
+		break;
+	}
+
+	return len;
+}
+
+/*******************************************************************
+ Send a packet_struct.
+******************************************************************/
+
+BOOL send_packet(struct packet_struct *p)
+{
+	char buf[1024];
+	int len=0;
+
+	memset(buf,'\0',sizeof(buf));
+
+	len = build_packet(buf, p);
+
+	if (!len)
+		return(False);
+
+	return(send_udp(p->fd,buf,len,p->ip,p->port));
+}
+
+/****************************************************************************
+ Receive a packet with timeout on a open UDP filedescriptor.
+ The timeout is in milliseconds
+***************************************************************************/
+
+struct packet_struct *receive_packet(int fd,enum packet_type type,int t)
+{
+	fd_set fds;
+	struct timeval timeout;
+	int ret;
+
+	FD_ZERO(&fds);
+	FD_SET(fd,&fds);
+	timeout.tv_sec = t/1000;
+	timeout.tv_usec = 1000*(t%1000);
+
+	if ((ret = sys_select_intr(fd+1,&fds,NULL,NULL,&timeout)) == -1) {
+		/* errno should be EBADF or EINVAL. */
+		DEBUG(0,("select returned -1, errno = %s (%d)\n", strerror(errno), errno));
+		return NULL;
+	}
+
+	if (ret == 0) /* timeout */
+		return NULL;
+
+	if (FD_ISSET(fd,&fds)) 
+		return(read_packet(fd,type));
+	
+	return(NULL);
+}
+
+/****************************************************************************
+ Receive a UDP/137 packet either via UDP or from the unexpected packet
+ queue. The packet must be a reply packet and have the specified trn_id.
+ The timeout is in milliseconds.
+***************************************************************************/
+
+struct packet_struct *receive_nmb_packet(int fd, int t, int trn_id)
+{
+	struct packet_struct *p;
+
+	p = receive_packet(fd, NMB_PACKET, t);
+
+	if (p && p->packet.nmb.header.response &&
+			p->packet.nmb.header.name_trn_id == trn_id) {
+		return p;
+	}
+	if (p)
+		free_packet(p);
+
+	/* try the unexpected packet queue */
+	return receive_unexpected(NMB_PACKET, trn_id, NULL);
+}
+
+/****************************************************************************
+ Receive a UDP/138 packet either via UDP or from the unexpected packet
+ queue. The packet must be a reply packet and have the specified mailslot name
+ The timeout is in milliseconds.
+***************************************************************************/
+
+struct packet_struct *receive_dgram_packet(int fd, int t, const char *mailslot_name)
+{
+	struct packet_struct *p;
+
+	p = receive_packet(fd, DGRAM_PACKET, t);
+
+	if (p && match_mailslot_name(p, mailslot_name)) {
+		return p;
+	}
+	if (p)
+		free_packet(p);
+
+	/* try the unexpected packet queue */
+	return receive_unexpected(DGRAM_PACKET, 0, mailslot_name);
+}
+
+/****************************************************************************
+ See if a datagram has the right mailslot name.
+***************************************************************************/
+
+BOOL match_mailslot_name(struct packet_struct *p, const char *mailslot_name)
+{
+	struct dgram_packet *dgram = &p->packet.dgram;
+	char *buf;
+
+	buf = &dgram->data[0];
+	buf -= 4;
+
+	buf = smb_buf(buf);
+
+	if (memcmp(buf, mailslot_name, strlen(mailslot_name)+1) == 0) {
+		return True;
+	}
+
+	return False;
+}
+
+/****************************************************************************
+ Return the number of bits that match between two 4 character buffers
+***************************************************************************/
+
+int matching_quad_bits(unsigned char *p1, unsigned char *p2)
+{
+	int i, j, ret = 0;
+	for (i=0; i<4; i++) {
+		if (p1[i] != p2[i])
+			break;
+		ret += 8;
+	}
+
+	if (i==4)
+		return ret;
+
+	for (j=0; j<8; j++) {
+		if ((p1[i] & (1<<(7-j))) != (p2[i] & (1<<(7-j))))
+			break;
+		ret++;
+	}	
+	
+	return ret;
+}
+
+static unsigned char sort_ip[4];
+
+/****************************************************************************
+ Compare two query reply records.
+***************************************************************************/
+
+static int name_query_comp(unsigned char *p1, unsigned char *p2)
+{
+	return matching_quad_bits(p2+2, sort_ip) - matching_quad_bits(p1+2, sort_ip);
+}
+
+/****************************************************************************
+ Sort a set of 6 byte name query response records so that the IPs that
+ have the most leading bits in common with the specified address come first.
+***************************************************************************/
+
+void sort_query_replies(char *data, int n, struct in_addr ip)
+{
+	if (n <= 1)
+		return;
+
+	putip(sort_ip, (char *)&ip);
+
+	qsort(data, n, 6, QSORT_CAST name_query_comp);
+}
+
+#define TRUNCATE_NETBIOS_NAME 1
+
+/*******************************************************************
+ Convert, possibly using a stupid microsoft-ism which has destroyed
+ the transport independence of netbios (for CIFS vendors that usually
+ use the Win95-type methods, not for NT to NT communication, which uses
+ DCE/RPC and therefore full-length unicode strings...) a dns name into
+ a netbios name.
+
+ The netbios name (NOT necessarily null-terminated) is truncated to 15
+ characters.
+
+ ******************************************************************/
+
+char *dns_to_netbios_name(const char *dns_name)
+{
+	static nstring netbios_name;
+	int i;
+	StrnCpy(netbios_name, dns_name, MAX_NETBIOSNAME_LEN-1);
+	netbios_name[15] = 0;
+	
+#ifdef TRUNCATE_NETBIOS_NAME
+	/* ok.  this is because of a stupid microsoft-ism.  if the called host
+	   name contains a '.', microsoft clients expect you to truncate the
+	   netbios name up to and including the '.'  this even applies, by
+	   mistake, to workgroup (domain) names, which is _really_ daft.
+	 */
+	for (i = 0; i >= 15; i--) {
+		if (netbios_name[i] == '.') {
+			netbios_name[i] = 0;
+			break;
+		}
+	}
+#endif /* TRUNCATE_NETBIOS_NAME */
+
+	return netbios_name;
+}
+
+/****************************************************************************
+ Interpret the weird netbios "name" into a unix fstring. Return the name type.
+****************************************************************************/
+
+static int name_interpret(char *in, fstring name)
+{
+	int ret;
+	int len = (*in++) / 2;
+	fstring out_string;
+	char *out = out_string;
+
+	*out=0;
+
+	if (len > 30 || len<1)
+		return(0);
+
+	while (len--) {
+		if (in[0] < 'A' || in[0] > 'P' || in[1] < 'A' || in[1] > 'P') {
+			*out = 0;
+			return(0);
+		}
+		*out = ((in[0]-'A')<<4) + (in[1]-'A');
+		in += 2;
+		out++;
+	}
+	ret = out[-1];
+	out[-1] = 0;
+
+#ifdef NETBIOS_SCOPE
+	/* Handle any scope names */
+	while(*in) {
+		*out++ = '.'; /* Scope names are separated by periods */
+		len = *(unsigned char *)in++;
+		StrnCpy(out, in, len);
+		out += len;
+		*out=0;
+		in += len;
+	}
+#endif
+	pull_ascii_fstring(name, out_string);
+
+	return(ret);
+}
+
+/****************************************************************************
+ Mangle a name into netbios format.
+ Note:  <Out> must be (33 + strlen(scope) + 2) bytes long, at minimum.
+****************************************************************************/
+
+int name_mangle( char *In, char *Out, char name_type )
+{
+	int   i;
+	int   len;
+	nstring buf;
+	char *p = Out;
+
+	/* Safely copy the input string, In, into buf[]. */
+	if (strcmp(In,"*") == 0)
+		put_name(buf, "*", '\0', 0x00);
+	else {
+		/* We use an fstring here as mb dos names can expend x3 when
+		   going to utf8. */
+		fstring buf_unix;
+		nstring buf_dos;
+
+		pull_ascii_fstring(buf_unix, In);
+		strupper_m(buf_unix);
+
+		push_ascii_nstring(buf_dos, buf_unix);
+		put_name(buf, buf_dos, ' ', name_type);
+	}
+
+	/* Place the length of the first field into the output buffer. */
+	p[0] = 32;
+	p++;
+
+	/* Now convert the name to the rfc1001/1002 format. */
+	for( i = 0; i < MAX_NETBIOSNAME_LEN; i++ ) {
+		p[i*2]     = ( (buf[i] >> 4) & 0x000F ) + 'A';
+		p[(i*2)+1] = (buf[i] & 0x000F) + 'A';
+	}
+	p += 32;
+	p[0] = '\0';
+
+	/* Add the scope string. */
+	for( i = 0, len = 0; *(global_scope()) != '\0'; i++, len++ ) {
+		switch( (global_scope())[i] ) {
+			case '\0':
+				p[0] = len;
+				if( len > 0 )
+					p[len+1] = 0;
+				return( name_len(Out) );
+			case '.':
+				p[0] = len;
+				p   += (len + 1);
+				len  = -1;
+				break;
+			default:
+				p[len+1] = (global_scope())[i];
+				break;
+		}
+	}
+
+	return( name_len(Out) );
+}
+
+/****************************************************************************
+ Find a pointer to a netbios name.
+****************************************************************************/
+
+static char *name_ptr(char *buf,int ofs)
+{
+	unsigned char c = *(unsigned char *)(buf+ofs);
+
+	if ((c & 0xC0) == 0xC0) {
+		uint16 l = RSVAL(buf, ofs) & 0x3FFF;
+		DEBUG(5,("name ptr to pos %d from %d is %s\n",l,ofs,buf+l));
+		return(buf + l);
+	} else {
+		return(buf+ofs);
+	}
+}  
+
+/****************************************************************************
+ Extract a netbios name from a buf (into a unix string) return name type.
+****************************************************************************/
+
+int name_extract(char *buf,int ofs, fstring name)
+{
+	char *p = name_ptr(buf,ofs);
+	int d = PTR_DIFF(p,buf+ofs);
+
+	name[0] = '\0';
+	if (d < -50 || d > 50)
+		return(0);
+	return(name_interpret(p,name));
+}
+  
+/****************************************************************************
+ Return the total storage length of a mangled name.
+****************************************************************************/
+
+int name_len(char *s1)
+{
+	/* NOTE: this argument _must_ be unsigned */
+	unsigned char *s = (unsigned char *)s1;
+	int len;
+
+	/* If the two high bits of the byte are set, return 2. */
+	if (0xC0 == (*s & 0xC0))
+		return(2);
+
+	/* Add up the length bytes. */
+	for (len = 1; (*s); s += (*s) + 1) {
+		len += *s + 1;
+		SMB_ASSERT(len < 80);
+	}
+
+	return(len);
+}