/* tcp_usrreq.c - TCP interface routines *//* Copyright 1984 - 2002 Wind River Systems, Inc. */#include "copyright_wrs.h"/* * Copyright (c) 1982, 1986, 1988, 1993, 1995 *	The Regents of the University of California.  All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright *    notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in the *    documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software *    must display the following acknowledgement: *	This product includes software developed by the University of *	California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors *    may be used to endorse or promote products derived from this software *    without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * *	@(#)tcp_usrreq.c	8.5 (Berkeley) 6/21/95 *//*modification history--------------------03i,05jun02,vvv  fixed Nagle for large writes (SPR #72213)03h,21mar02,wap  avoid making local port of TCP connection the same as                 the foreign port (SPR #73104)03g,12oct01,rae  merge from truestack ver 03j, base 03e03f,14nov00,ham  remoeved tcpstates declaration(SPR 62272).03e,26aug98,n_s  added return val check for mBufClGet in tcp_ctloutput.                  spr #22238.03d,07jul97,vin  in tcp_usrreq case PRU_DETACH simplified.03c,08mar97,vin  added changes to accomodate changes in pcb structure for		 hash look ups.03b,22nov96,vin  modified for cluster support, replace m_get(..) with 		 mBufClGet(..).03a,03mar96,vin  created from BSD4.4 stuff,integrated with 02o of tcp_usrreq.c.*//*DESCRIPTION*/#include "vxWorks.h"#include "net/mbuf.h"#include "sys/socket.h"#include "net/socketvar.h"#include "net/protosw.h"#include "errno.h"#include "sys/stat.h"#include "net/if.h"#include "net/route.h"#include "netinet/in.h"#include "netinet/in_pcb.h"#include "netinet/in_systm.h"#include "netinet/in_var.h"#include "netinet/ip.h"#include "netinet/ip_var.h"#include "netinet/tcp.h"#include "netinet/tcp_fsm.h"#include "netinet/tcp_seq.h"#include "netinet/tcp_timer.h"#include "netinet/tcp_var.h"#include "netinet/tcpip.h"#include "netinet/tcp_debug.h"#include "net/systm.h"#ifdef WV_INSTRUMENTATION#ifdef INCLUDE_WVNET#include "wvNetLib.h"#endif#endif#ifdef VIRTUAL_STACK#include "netinet/vsLib.h"#elseIMPORT int tcp_keepinit;#endif /* VIRTUAL_STACK */IMPORT unsigned long (*pTcpRandHook)(void);LOCAL void	tcpTraceStub ();LOCAL void	tcpReportStub ();VOIDFUNCPTR	tcpTraceRtn = tcpTraceStub;		/* exported */VOIDFUNCPTR	tcpReportRtn = tcpReportStub;		/* exported *//* * TCP protocol interface to socket abstraction. */#ifdef WV_INSTRUMENTATION#ifdef INCLUDE_WVNET    /* Set common fields of event identifiers for this module. */LOCAL UCHAR wvNetModuleId = WV_NET_TCPREQ_MODULE; /* Value for tcp_usrreq.c */LOCAL UCHAR wvNetLocalFilter = WV_NET_NONE;     /* Available event filter */LOCAL ULONG wvNetEventId;       /* Event identifier: see wvNetLib.h */#endif    /* INCLUDE_WVNET */#endif/* * Process a TCP user request for TCP tb.  If this is a send request * then m is the mbuf chain of send data.  If this is a timer expiration * (called from the software clock routine), then timertype tells which timer. *//*ARGSUSED*/inttcp_usrreq(so, req, m, nam, control)	struct socket *so;	int req;	struct mbuf *m, *nam, *control;{	register struct inpcb *inp;	register struct tcpcb *tp = NULL;	int s;	int error = 0;	int ostate;#ifdef WV_INSTRUMENTATION#ifdef INCLUDE_WVNET    /* WV_NET_INFO event */    WV_NET_MARKER_2 (NET_AUX_EVENT, WV_NET_INFO, 47, 8,                     WV_NETEVENT_TCPREQ_START, so->so_fd, req)#endif  /* INCLUDE_WVNET */#endif	if (req == PRU_CONTROL)		return (in_control(so, (u_long)m, (caddr_t)nam,			(struct ifnet *)control));	if (control && control->m_len) {		m_freem(control);		if (m)			m_freem(m);#ifdef WV_INSTRUMENTATION#ifdef INCLUDE_WVNET    /* WV_NET_ERROR event */        WV_NET_MARKER_2 (NET_AUX_EVENT, WV_NET_ERROR, 38, 4,                         WV_NETEVENT_TCPREQ_BADMEM, so->so_fd, req)#endif  /* INCLUDE_WVNET */#endif		return (EINVAL);	}	s = splnet();	inp = sotoinpcb(so);	/*	 * When a TCP is attached to a socket, then there will be	 * a (struct inpcb) pointed at by the socket, and this	 * structure will point at a subsidary (struct tcpcb).	 */	if (inp == 0 && req != PRU_ATTACH) {		splx(s);#if 0		/*		 * The following corrects an mbuf leak under rare		 * circumstances, but has not been fully tested.		 */		if (m && req != PRU_SENSE)			m_freem(m);#else		/* safer version of fix for mbuf leak */		if (m && (req == PRU_SEND || req == PRU_SENDOOB))			m_freem(m);#endif#ifdef WV_INSTRUMENTATION#ifdef INCLUDE_WVNET    /* WV_NET_ERROR event */        WV_NET_MARKER_2 (NET_AUX_EVENT, WV_NET_ERROR, 39, 5,                         WV_NETEVENT_TCPREQ_NOPCB, so->so_fd, req)#endif  /* INCLUDE_WVNET */#endif		return (EINVAL);		/* XXX */	}	if (inp) {		tp = intotcpcb(inp);		/* WHAT IF TP IS 0? */#ifdef KPROF		tcp_acounts[tp->t_state][req]++;#endif		ostate = tp->t_state;	} else		ostate = 0;	switch (req) {	/*	 * TCP attaches to socket via PRU_ATTACH, reserving space,	 * and an internet control block.	 */	case PRU_ATTACH:		if (inp) {			error = EISCONN;			break;		}		error = tcp_attach(so);		if (error)			break;                /* TCP sockets use path MTU discovery by default. */                so->so_options |= SO_USEPATHMTU;		if ((so->so_options & SO_LINGER) && so->so_linger == 0)			so->so_linger = TCP_LINGERTIME;		tp = sototcpcb(so);		break;	/*	 * PRU_DETACH detaches the TCP protocol from the socket.	 * If the protocol state is non-embryonic, then can't	 * do this directly: have to initiate a PRU_DISCONNECT,	 * which may finish later; embryonic TCB's can just	 * be discarded here.	 */	case PRU_DETACH:            tp = tcp_disconnect(tp);            break;	/*	 * Give the socket an address.	 */	case PRU_BIND:		error = in_pcbbind(inp, nam);		if (error)			break;		break;	/*	 * Prepare to accept connections.	 */	case PRU_LISTEN:		if (inp->inp_lport == 0)			error = in_pcbbind(inp, (struct mbuf *)0);		if (error == 0)			tp->t_state = TCPS_LISTEN;		break;	/*	 * Initiate connection to peer.	 * Create a template for use in transmissions on this connection.	 * Enter SYN_SENT state, and mark socket as connecting.	 * Start keep-alive timer, and seed output sequence space.	 * Send initial segment on connection.	 */	case PRU_CONNECT:		if (inp->inp_lport == 0) {			error = in_pcbbind(inp, (struct mbuf *)0);			if (error)				break;			/*			 * Avoid case where ephemeral port for local			 * side of connection is the same as destination			 * port for foreign side.			 */			if (inp->inp_lport ==			    (mtod (nam, struct sockaddr_in *))->sin_port)			    {				inp->inp_lport = 0;				error = in_pcbbind (inp, (struct mbuf *)0);				if (error)					break;			    }		}		error = in_pcbconnect(inp, nam);		if (error)			break;		tp->t_template = tcp_template(tp);		if (tp->t_template == 0) {			in_pcbdisconnect(inp);			error = ENOBUFS;			break;		}		/* Compute window scaling to request.  */		while (tp->request_r_scale < TCP_MAX_WINSHIFT &&		    (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)			tp->request_r_scale++;		soisconnecting(so);		tcpstat.tcps_connattempt++;		tp->t_state = TCPS_SYN_SENT;               	tp->t_timer[TCPT_KEEP] = tcp_keepinit;     		tp->iss = tcp_iss;		tcp_iss += TCP_ISSINCR/4 + ((0x0000ffff) & (pTcpRandHook() >> 16));		tcp_sendseqinit(tp);		error = tcp_output(tp);		break;	/*	 * Create a TCP connection between two sockets.	 */	case PRU_CONNECT2:		error = EOPNOTSUPP;		break;	/*	 * Initiate disconnect from peer.	 * If connection never passed embryonic stage, just drop;	 * else if don't need to let data drain, then can just drop anyways,	 * else have to begin TCP shutdown process: mark socket disconnecting,	 * drain unread data, state switch to reflect user close, and	 * send segment (e.g. FIN) to peer.  Socket will be really disconnected	 * when peer sends FIN and acks ours.	 *	 * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.	 */	case PRU_DISCONNECT:		tp = tcp_disconnect(tp);		break;	/*	 * Accept a connection.  Essentially all the work is	 * done at higher levels; just return the address	 * of the peer, storing through addr.	 */	case PRU_ACCEPT:		in_setpeeraddr(inp, nam);		break;	/*	 * Mark the connection as being incapable of further output.	 */	case PRU_SHUTDOWN:		socantsendmore(so);		tp = tcp_usrclosed(tp);		if (tp)			error = tcp_output(tp);		break;	/*