initial import of NetBSD tree

1 files changed, 555 insertions, 0 deletions

diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
new file mode 100644
index 00000000000..c0cda168fa1
--- /dev/null
+++ b/sys/netinet/tcp_usrreq.c
@@ -0,0 +1,555 @@
+/*	$NetBSD: tcp_usrreq.c,v 1.17 1995/09/30 07:02:05 thorpej Exp $	*/
+
+/*
+ * Copyright (c) 1982, 1986, 1988, 1993
+ *	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	8.2 (Berkeley) 1/3/94
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/protosw.h>
+#include <sys/errno.h>
+#include <sys/stat.h>
+
+#include <net/if.h>
+#include <net/route.h>
+
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/in_var.h>
+#include <netinet/ip.h>
+#include <netinet/in_pcb.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>
+
+/*
+ * TCP protocol interface to socket abstraction.
+ */
+extern	char *tcpstates[];
+
+/*
+ * 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*/
+int
+tcp_usrreq(so, req, m, nam, control)
+	struct socket *so;
+	int req;
+	struct mbuf *m, *nam, *control;
+{
+	register struct inpcb *inp;
+	register struct tcpcb *tp;
+	int s;
+	int error = 0;
+	int ostate;
+
+	if (req == PRU_CONTROL)
+		return (in_control(so, (long)m, (caddr_t)nam,
+			(struct ifnet *)control));
+	if (control && control->m_len) {
+		m_freem(control);
+		if (m)
+			m_freem(m);
+		return (EINVAL);
+	}
+
+	s = splsoftnet();
+	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);
+		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;
+		if ((so->so_options & SO_LINGER) && so->so_linger == 0)
+			so->so_linger = TCP_LINGERTIME * hz;
+		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:
+		if (tp->t_state > TCPS_LISTEN)
+			tp = tcp_disconnect(tp);
+		else
+			tp = tcp_close(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;
+		}
+		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] = TCPTV_KEEP_INIT;
+		tp->iss = tcp_iss; tcp_iss += TCP_ISSINCR/2;
+		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;
+
+	/*
+	 * After a receive, possibly send window update to peer.
+	 */
+	case PRU_RCVD:
+		(void) tcp_output(tp);
+		break;
+
+	/*
+	 * Do a send by putting data in output queue and updating urgent
+	 * marker if URG set.  Possibly send more data.
+	 */
+	case PRU_SEND:
+		sbappend(&so->so_snd, m);
+		error = tcp_output(tp);
+		break;
+
+	/*
+	 * Abort the TCP.
+	 */
+	case PRU_ABORT:
+		tp = tcp_drop(tp, ECONNABORTED);
+		break;
+
+	case PRU_SENSE:
+		((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat;
+		(void) splx(s);
+		return (0);
+
+	case PRU_RCVOOB:
+		if ((so->so_oobmark == 0 &&
+		    (so->so_state & SS_RCVATMARK) == 0) ||
+		    so->so_options & SO_OOBINLINE ||
+		    tp->t_oobflags & TCPOOB_HADDATA) {
+			error = EINVAL;
+			break;
+		}
+		if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
+			error = EWOULDBLOCK;
+			break;
+		}
+		m->m_len = 1;
+		*mtod(m, caddr_t) = tp->t_iobc;
+		if (((long)nam & MSG_PEEK) == 0)
+			tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
+		break;
+
+	case PRU_SENDOOB:
+		if (sbspace(&so->so_snd) < -512) {
+			m_freem(m);
+			error = ENOBUFS;
+			break;
+		}
+		/*
+		 * According to RFC961 (Assigned Protocols),
+		 * the urgent pointer points to the last octet
+		 * of urgent data.  We continue, however,
+		 * to consider it to indicate the first octet
+		 * of data past the urgent section.
+		 * Otherwise, snd_up should be one lower.
+		 */
+		sbappend(&so->so_snd, m);
+		tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
+		tp->t_force = 1;
+		error = tcp_output(tp);
+		tp->t_force = 0;
+		break;
+
+	case PRU_SOCKADDR:
+		in_setsockaddr(inp, nam);
+		break;
+
+	case PRU_PEERADDR:
+		in_setpeeraddr(inp, nam);
+		break;
+
+	/*
+	 * TCP slow timer went off; going through this
+	 * routine for tracing's sake.
+	 */
+	case PRU_SLOWTIMO:
+		tp = tcp_timers(tp, (long)nam);
+		req |= (long)nam << 8;		/* for debug's sake */
+		break;
+
+	default:
+		panic("tcp_usrreq");
+	}
+	if (tp && (so->so_options & SO_DEBUG))
+		tcp_trace(TA_USER, ostate, tp, (struct tcpiphdr *)0, req);
+	splx(s);
+	return (error);
+}
+
+int
+tcp_ctloutput(op, so, level, optname, mp)
+	int op;
+	struct socket *so;
+	int level, optname;
+	struct mbuf **mp;
+{
+	int error = 0, s;
+	struct inpcb *inp;
+	register struct tcpcb *tp;
+	register struct mbuf *m;
+	register int i;
+
+	s = splsoftnet();
+	inp = sotoinpcb(so);
+	if (inp == NULL) {
+		splx(s);
+		if (op == PRCO_SETOPT && *mp)
+			(void) m_free(*mp);
+		return (ECONNRESET);
+	}
+	if (level != IPPROTO_TCP) {
+		error = ip_ctloutput(op, so, level, optname, mp);
+		splx(s);
+		return (error);
+	}
+	tp = intotcpcb(inp);
+
+	switch (op) {
+
+	case PRCO_SETOPT:
+		m = *mp;
+		switch (optname) {
+
+		case TCP_NODELAY:
+			if (m == NULL || m->m_len < sizeof (int))
+				error = EINVAL;
+			else if (*mtod(m, int *))
+				tp->t_flags |= TF_NODELAY;
+			else
+				tp->t_flags &= ~TF_NODELAY;
+			break;
+
+		case TCP_MAXSEG:
+			if (m && (i = *mtod(m, int *)) > 0 && i <= tp->t_maxseg)
+				tp->t_maxseg = i;
+			else
+				error = EINVAL;
+			break;
+
+		default:
+			error = ENOPROTOOPT;
+			break;
+		}
+		if (m)
+			(void) m_free(m);
+		break;
+
+	case PRCO_GETOPT:
+		*mp = m = m_get(M_WAIT, MT_SOOPTS);
+		m->m_len = sizeof(int);
+
+		switch (optname) {
+		case TCP_NODELAY:
+			*mtod(m, int *) = tp->t_flags & TF_NODELAY;
+			break;
+		case TCP_MAXSEG:
+			*mtod(m, int *) = tp->t_maxseg;
+			break;
+		default:
+			error = ENOPROTOOPT;
+			break;
+		}
+		break;
+	}
+	splx(s);
+	return (error);
+}
+
+#ifndef TCP_SENDSPACE
+#define	TCP_SENDSPACE	1024*16;
+#endif
+u_long	tcp_sendspace = TCP_SENDSPACE;
+#ifndef TCP_RECVSPACE
+#define	TCP_RECVSPACE	1024*16;
+#endif
+u_long	tcp_recvspace = TCP_RECVSPACE;
+
+/*
+ * Attach TCP protocol to socket, allocating
+ * internet protocol control block, tcp control block,
+ * bufer space, and entering LISTEN state if to accept connections.
+ */
+int
+tcp_attach(so)
+	struct socket *so;
+{
+	register struct tcpcb *tp;
+	struct inpcb *inp;
+	int error;
+
+	if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
+		error = soreserve(so, tcp_sendspace, tcp_recvspace);
+		if (error)
+			return (error);
+	}
+	error = in_pcballoc(so, &tcbtable);
+	if (error)
+		return (error);
+	inp = sotoinpcb(so);
+	tp = tcp_newtcpcb(inp);
+	if (tp == 0) {
+		int nofd = so->so_state & SS_NOFDREF;	/* XXX */
+
+		so->so_state &= ~SS_NOFDREF;	/* don't free the socket yet */
+		in_pcbdetach(inp);
+		so->so_state |= nofd;
+		return (ENOBUFS);
+	}
+	tp->t_state = TCPS_CLOSED;
+	return (0);
+}
+
+/*
+ * Initiate (or continue) disconnect.
+ * If embryonic state, just send reset (once).
+ * If in ``let data drain'' option and linger null, just drop.
+ * Otherwise (hard), mark socket disconnecting and drop
+ * current input data; switch states based on user close, and
+ * send segment to peer (with FIN).
+ */
+struct tcpcb *
+tcp_disconnect(tp)
+	register struct tcpcb *tp;
+{
+	struct socket *so = tp->t_inpcb->inp_socket;
+
+	if (TCPS_HAVEESTABLISHED(tp->t_state) == 0)
+		tp = tcp_close(tp);
+	else if ((so->so_options & SO_LINGER) && so->so_linger == 0)
+		tp = tcp_drop(tp, 0);
+	else {
+		soisdisconnecting(so);
+		sbflush(&so->so_rcv);
+		tp = tcp_usrclosed(tp);
+		if (tp)
+			(void) tcp_output(tp);
+	}
+	return (tp);
+}
+
+/*
+ * User issued close, and wish to trail through shutdown states:
+ * if never received SYN, just forget it.  If got a SYN from peer,
+ * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
+ * If already got a FIN from peer, then almost done; go to LAST_ACK
+ * state.  In all other cases, have already sent FIN to peer (e.g.
+ * after PRU_SHUTDOWN), and just have to play tedious game waiting
+ * for peer to send FIN or not respond to keep-alives, etc.
+ * We can let the user exit from the close as soon as the FIN is acked.
+ */
+struct tcpcb *
+tcp_usrclosed(tp)
+	register struct tcpcb *tp;
+{
+
+	switch (tp->t_state) {
+
+	case TCPS_CLOSED:
+	case TCPS_LISTEN:
+	case TCPS_SYN_SENT:
+		tp->t_state = TCPS_CLOSED;
+		tp = tcp_close(tp);
+		break;
+
+	case TCPS_SYN_RECEIVED:
+	case TCPS_ESTABLISHED:
+		tp->t_state = TCPS_FIN_WAIT_1;
+		break;
+
+	case TCPS_CLOSE_WAIT:
+		tp->t_state = TCPS_LAST_ACK;
+		break;
+	}
+	if (tp && tp->t_state >= TCPS_FIN_WAIT_2)
+		soisdisconnected(tp->t_inpcb->inp_socket);
+	return (tp);
+}
+
+/*
+ * Sysctl for tcp variables.
+ */
+int
+tcp_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
+	int *name;
+	u_int namelen;
+	void *oldp;
+	size_t *oldlenp;
+	void *newp;
+	size_t newlen;
+{
+
+	/* All sysctl names at this level are terminal. */
+	if (namelen != 1)
+		return (ENOTDIR);
+
+	switch (name[0]) {
+	case TCPCTL_RFC1323:
+		return (sysctl_int(oldp, oldlenp, newp, newlen,
+		    &tcp_do_rfc1323));
+
+	default:
+		return (ENOPROTOOPT);
+	}
+	/* NOTREACHED */
+}