X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/f3cdd7218787350474c0262a1e146f37f11b3767..0880b18ef40ee52f08a23527900e6354275bcc33:/usr/src/sys/netinet/tcp_subr.c

diff --git a/usr/src/sys/netinet/tcp_subr.c b/usr/src/sys/netinet/tcp_subr.c
index 22da4cce08..179353f875 100644
--- a/usr/src/sys/netinet/tcp_subr.c
+++ b/usr/src/sys/netinet/tcp_subr.c
@@ -1,24 +1,34 @@
-/*	tcp_subr.c	4.19	82/03/24	*/
-
-#include "../h/param.h"
-#include "../h/systm.h"
-#include "../h/mbuf.h"
-#include "../h/socket.h"
-#include "../h/socketvar.h"
-#include "../h/protosw.h"
-#include "../net/in.h"
-#include "../net/in_pcb.h"
-#include "../net/in_systm.h"
+/*
+ * Copyright (c) 1982, 1986 Regents of the University of California.
+ * All rights reserved.  The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ *
+ *	@(#)tcp_subr.c	7.1 (Berkeley) %G%
+ */
+
+#include "param.h"
+#include "systm.h"
+#include "mbuf.h"
+#include "socket.h"
+#include "socketvar.h"
+#include "protosw.h"
+#include "errno.h"
+
+#include "../net/route.h"
 #include "../net/if.h"
-#include "../net/ip.h"
-#include "../net/ip_var.h"
-#include "../net/tcp.h"
-#include "../net/tcp_fsm.h"
-#include "../net/tcp_seq.h"
-#include "../net/tcp_timer.h"
-#include "../net/tcp_var.h"
-#include "../net/tcpip.h"
-#include "../errno.h"
+
+#include "in.h"
+#include "in_pcb.h"
+#include "in_systm.h"
+#include "ip.h"
+#include "ip_var.h"
+#include "ip_icmp.h"
+#include "tcp.h"
+#include "tcp_fsm.h"
+#include "tcp_seq.h"
+#include "tcp_timer.h"
+#include "tcp_var.h"
+#include "tcpip.h"
 
 /*
  * Tcp initialization
@@ -26,7 +36,6 @@
 tcp_init()
 {
 
-COUNT(TCP_INIT);
 	tcp_iss = 1;		/* wrong */
 	tcb.inp_next = tcb.inp_prev = &tcb;
 	tcp_alpha = TCP_ALPHA;
@@ -47,13 +56,14 @@ tcp_template(tp)
 	register struct mbuf *m;
 	register struct tcpiphdr *n;
 
-COUNT(TCP_TEMPLATE);
-	m = m_get(M_WAIT);
-	if (m == 0)
-		return (0);
-	m->m_off = MMAXOFF - sizeof (struct tcpiphdr);
-	m->m_len = sizeof (struct tcpiphdr);
-	n = mtod(m, struct tcpiphdr *);
+	if ((n = tp->t_template) == 0) {
+		m = m_get(M_WAIT, MT_HEADER);
+		if (m == NULL)
+			return (0);
+		m->m_off = MMAXOFF - sizeof (struct tcpiphdr);
+		m->m_len = sizeof (struct tcpiphdr);
+		n = mtod(m, struct tcpiphdr *);
+	}
 	n->ti_next = n->ti_prev = 0;
 	n->ti_x1 = 0;
 	n->ti_pr = IPPROTO_TCP;
@@ -94,15 +104,16 @@ tcp_respond(tp, ti, ack, seq, flags)
 {
 	struct mbuf *m;
 	int win = 0, tlen;
+	struct route *ro = 0;
 
-COUNT(TCP_RESPOND);
-	if (tp)
+	if (tp) {
 		win = sbspace(&tp->t_inpcb->inp_socket->so_rcv);
+		ro = &tp->t_inpcb->inp_route;
+	}
 	if (flags == 0) {
-		m = m_get(M_DONTWAIT);
-		if (m == 0)
+		m = m_get(M_DONTWAIT, MT_HEADER);
+		if (m == NULL)
 			return;
-		m->m_off = MMINOFF;
 		m->m_len = sizeof (struct tcpiphdr) + 1;
 		*mtod(m, struct tcpiphdr *) = *ti;
 		ti = mtod(m, struct tcpiphdr *);
@@ -122,26 +133,18 @@ COUNT(TCP_RESPOND);
 	}
 	ti->ti_next = ti->ti_prev = 0;
 	ti->ti_x1 = 0;
-	ti->ti_len = sizeof (struct tcphdr) + tlen;
-	ti->ti_seq = seq;
-	ti->ti_ack = ack;
-#if vax
-	ti->ti_len = htons((u_short)ti->ti_len);
-	ti->ti_seq = htonl(ti->ti_seq);
-	ti->ti_ack = htonl(ti->ti_ack);
-#endif
+	ti->ti_len = htons((u_short)(sizeof (struct tcphdr) + tlen));
+	ti->ti_seq = htonl(seq);
+	ti->ti_ack = htonl(ack);
 	ti->ti_x2 = 0;
 	ti->ti_off = sizeof (struct tcphdr) >> 2;
 	ti->ti_flags = flags;
-	ti->ti_win = win;
-#if vax
-	ti->ti_win = htons(ti->ti_win);
-#endif
+	ti->ti_win = htons((u_short)win);
 	ti->ti_urp = 0;
 	ti->ti_sum = in_cksum(m, sizeof (struct tcpiphdr) + tlen);
 	((struct ip *)ti)->ip_len = sizeof (struct tcpiphdr) + tlen;
 	((struct ip *)ti)->ip_ttl = TCP_TTL;
-	(void) ip_output(m, (struct mbuf *)0, 0);
+	(void) ip_output(m, (struct mbuf *)0, ro, 0);
 }
 
 /*
@@ -153,17 +156,18 @@ struct tcpcb *
 tcp_newtcpcb(inp)
 	struct inpcb *inp;
 {
-	struct mbuf *m = m_getclr(M_DONTWAIT);
+	struct mbuf *m = m_getclr(M_DONTWAIT, MT_PCB);
 	register struct tcpcb *tp;
-COUNT(TCP_NEWTCPCB);
 
-	if (m == 0)
-		return (0);
+	if (m == NULL)
+		return ((struct tcpcb *)0);
 	tp = mtod(m, struct tcpcb *);
 	tp->seg_next = tp->seg_prev = (struct tcpiphdr *)tp;
-	tp->t_maxseg = 1024;
-	tp->t_flags = TF_NOOPT;		/* until all TCP's take options */
+	tp->t_maxseg = TCP_MSS;
+	tp->t_flags = 0;		/* sends options! */
 	tp->t_inpcb = inp;
+	tp->t_srtt = TCPTV_SRTTBASE;
+	tp->snd_cwnd = sbspace(&inp->inp_socket->so_snd);
 	inp->inp_ppcb = (caddr_t)tp;
 	return (tp);
 }
@@ -173,19 +177,19 @@ COUNT(TCP_NEWTCPCB);
  * the specified error.  If connection is synchronized,
  * then send a RST to peer.
  */
+struct tcpcb *
 tcp_drop(tp, errno)
-	struct tcpcb *tp;
+	register struct tcpcb *tp;
 	int errno;
 {
 	struct socket *so = tp->t_inpcb->inp_socket;
 
-COUNT(TCP_DROP);
 	if (TCPS_HAVERCVDSYN(tp->t_state)) {
 		tp->t_state = TCPS_CLOSED;
-		tcp_output(tp);
+		(void) tcp_output(tp);
 	}
 	so->so_error = errno;
-	tcp_close(tp);
+	return (tcp_close(tp));
 }
 
 /*
@@ -194,39 +198,86 @@ COUNT(TCP_DROP);
  *	discard internet protocol block
  *	wake up any sleepers
  */
+struct tcpcb *
 tcp_close(tp)
 	register struct tcpcb *tp;
 {
 	register struct tcpiphdr *t;
 	struct inpcb *inp = tp->t_inpcb;
 	struct socket *so = inp->inp_socket;
+	register struct mbuf *m;
 
-COUNT(TCP_CLOSE);
 	t = tp->seg_next;
-	for (; t != (struct tcpiphdr *)tp; t = (struct tcpiphdr *)t->ti_next)
-		m_freem(dtom(t));
+	while (t != (struct tcpiphdr *)tp) {
+		t = (struct tcpiphdr *)t->ti_next;
+		m = dtom(t->ti_prev);
+		remque(t->ti_prev);
+		m_freem(m);
+	}
 	if (tp->t_template)
 		(void) m_free(dtom(tp->t_template));
 	if (tp->t_tcpopt)
 		(void) m_free(dtom(tp->t_tcpopt));
-	if (tp->t_ipopt)
-		(void) m_free(dtom(tp->t_ipopt));
 	(void) m_free(dtom(tp));
 	inp->inp_ppcb = 0;
-	in_pcbdetach(inp);
 	soisdisconnected(so);
+	in_pcbdetach(inp);
+	return ((struct tcpcb *)0);
 }
 
 tcp_drain()
 {
 
-COUNT(TCP_DRAIN);
 }
 
-tcp_ctlinput(m)
-	struct mbuf *m;
+tcp_ctlinput(cmd, sa)
+	int cmd;
+	struct sockaddr *sa;
+{
+	extern u_char inetctlerrmap[];
+	struct sockaddr_in *sin;
+	int tcp_quench(), in_rtchange();
+
+	if ((unsigned)cmd > PRC_NCMDS)
+		return;
+	if (sa->sa_family != AF_INET && sa->sa_family != AF_IMPLINK)
+		return;
+	sin = (struct sockaddr_in *)sa;
+	if (sin->sin_addr.s_addr == INADDR_ANY)
+		return;
+
+	switch (cmd) {
+
+	case PRC_QUENCH:
+		in_pcbnotify(&tcb, &sin->sin_addr, 0, tcp_quench);
+		break;
+
+	case PRC_ROUTEDEAD:
+	case PRC_REDIRECT_NET:
+	case PRC_REDIRECT_HOST:
+	case PRC_REDIRECT_TOSNET:
+	case PRC_REDIRECT_TOSHOST:
+		in_pcbnotify(&tcb, &sin->sin_addr, 0, in_rtchange);
+		break;
+
+	default:
+		if (inetctlerrmap[cmd] == 0)
+			return;		/* XXX */
+		in_pcbnotify(&tcb, &sin->sin_addr, (int)inetctlerrmap[cmd],
+			(int (*)())0);
+	}
+}
+
+/*
+ * When a source quench is received, close congestion window
+ * to 80% of the outstanding data (but not less than one segment).
+ */
+tcp_quench(inp)
+	struct inpcb *inp;
 {
+	struct tcpcb *tp = intotcpcb(inp);
 
-COUNT(TCP_CTLINPUT);
-	m_freem(m);
+	if (tp)
+	    tp->snd_cwnd = MAX(8 * (tp->snd_nxt - tp->snd_una) / 10,
+		tp->t_maxseg);
 }