4.3BSD release version

[unix-history] / 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 701f53a..179353f 100644 (file)
--- a/usr/src/sys/netinet/tcp_subr.c
+++ b/usr/src/sys/netinet/tcp_subr.c
@@ -1,24 +1,34 @@
-/* tcp_subr.c 4.6 81/12/03 */
-
-#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/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
 
 /*
  * Tcp initialization


@@ -26,7 +36,6 @@
 tcp_init()
 {
 
 tcp_init()
 {
 

-COUNT(TCP_INIT);

        tcp_iss = 1;            /* wrong */
        tcb.inp_next = tcb.inp_prev = &tcb;
        tcp_alpha = TCP_ALPHA;
        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;
 
        register struct mbuf *m;
        register struct tcpiphdr *n;
 

-COUNT(TCP_TEMPLATE);
-       m = m_get(1);
-       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;
        n->ti_next = n->ti_prev = 0;
        n->ti_x1 = 0;
        n->ti_pr = IPPROTO_TCP;


@@ -86,45 +96,55 @@ COUNT(TCP_TEMPLATE);
  * In any case the ack and sequence number of the transmitted
  * segment are as specified by the parameters.
  */
  * In any case the ack and sequence number of the transmitted
  * segment are as specified by the parameters.
  */

-tcp_respond(ti, ack, seq, flags)
+tcp_respond(tp, ti, ack, seq, flags)
+       struct tcpcb *tp;

        register struct tcpiphdr *ti;
        tcp_seq ack, seq;
        int flags;
 {
        struct mbuf *m;
        register struct tcpiphdr *ti;
        tcp_seq ack, seq;
        int flags;
 {
        struct mbuf *m;

+       int win = 0, tlen;
+       struct route *ro = 0;

 
 

-COUNT(TCP_RESPOND);
+       if (tp) {
+               win = sbspace(&tp->t_inpcb->inp_socket->so_rcv);
+               ro = &tp->t_inpcb->inp_route;
+       }

        if (flags == 0) {
        if (flags == 0) {

-               m = m_get(0);
-               if (m == 0)
+               m = m_get(M_DONTWAIT, MT_HEADER);
+               if (m == NULL)

                        return;
                        return;

-               m->m_off = MMINOFF;
-               m->m_len = sizeof (struct tcpiphdr);
+               m->m_len = sizeof (struct tcpiphdr) + 1;

                *mtod(m, struct tcpiphdr *) = *ti;
                ti = mtod(m, struct tcpiphdr *);
                flags = TH_ACK;
                *mtod(m, struct tcpiphdr *) = *ti;
                ti = mtod(m, struct tcpiphdr *);
                flags = TH_ACK;

+               tlen = 1;

        } else {
        } else {

+               m = dtom(ti);

                m_freem(m->m_next);
                m->m_next = 0;
                m_freem(m->m_next);
                m->m_next = 0;

+               m->m_off = (int)ti - (int)m;

                m->m_len = sizeof (struct tcpiphdr);
 #define xchg(a,b,type) { type t; t=a; a=b; b=t; }
                xchg(ti->ti_dst.s_addr, ti->ti_src.s_addr, u_long);
                xchg(ti->ti_dport, ti->ti_sport, u_short);
 #undef xchg
                m->m_len = sizeof (struct tcpiphdr);
 #define xchg(a,b,type) { type t; t=a; a=b; b=t; }
                xchg(ti->ti_dst.s_addr, ti->ti_src.s_addr, u_long);
                xchg(ti->ti_dport, ti->ti_sport, u_short);
 #undef xchg

+               tlen = 0;

        }
        ti->ti_next = ti->ti_prev = 0;
        ti->ti_x1 = 0;
        }
        ti->ti_next = ti->ti_prev = 0;
        ti->ti_x1 = 0;

-       ti->ti_len = htons(sizeof (struct tcphdr));
+       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_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 = ti->ti_urp = 0;
-       ti->ti_sum = in_cksum(m, sizeof(struct tcpiphdr));
-       ((struct ip *)ti)->ip_len = sizeof(struct tcpiphdr);
+       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;
        ((struct ip *)ti)->ip_ttl = TCP_TTL;

-       (void) ip_output(m, (struct mbuf *)0);
+       (void) ip_output(m, (struct mbuf *)0, ro, 0);

 }
 
 /*
 }
 
 /*


@@ -136,16 +156,18 @@ struct tcpcb *
 tcp_newtcpcb(inp)
        struct inpcb *inp;
 {
 tcp_newtcpcb(inp)
        struct inpcb *inp;
 {

-       struct mbuf *m = m_getclr(0);
+       struct mbuf *m = m_getclr(M_DONTWAIT, MT_PCB);

        register struct tcpcb *tp;
        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 = mtod(m, struct tcpcb *);
        tp->seg_next = tp->seg_prev = (struct tcpiphdr *)tp;

-       tp->t_maxseg = 1024;
+       tp->t_maxseg = TCP_MSS;
+       tp->t_flags = 0;                /* sends options! */

        tp->t_inpcb = inp;
        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);
 }
        inp->inp_ppcb = (caddr_t)tp;
        return (tp);
 }


@@ -155,21 +177,19 @@ COUNT(TCP_NEWTCPCB);
  * the specified error.  If connection is synchronized,
  * then send a RST to peer.
  */
  * the specified error.  If connection is synchronized,
  * then send a RST to peer.
  */

+struct tcpcb *

 tcp_drop(tp, errno)
 tcp_drop(tp, errno)

-       struct tcpcb *tp;
+       register struct tcpcb *tp;

        int errno;
 {
        struct socket *so = tp->t_inpcb->inp_socket;
 
        int errno;
 {
        struct socket *so = tp->t_inpcb->inp_socket;
 

-COUNT(TCP_DROP);
-       if (TCPS_HAVERCVDSYN(tp->t_state) &&
-           TCPS_OURFINNOTACKED(tp->t_state)) {
+       if (TCPS_HAVERCVDSYN(tp->t_state)) {

                tp->t_state = TCPS_CLOSED;
                tp->t_state = TCPS_CLOSED;

-               tcp_output(tp);
+               (void) tcp_output(tp);

        }
        so->so_error = errno;
        }
        so->so_error = errno;

-       tcp_close(tp);
-       in_pcbdetach(tp->t_inpcb);
+       return (tcp_close(tp));

 }
 
 /*
 }
 
 /*


@@ -178,38 +198,86 @@ COUNT(TCP_DROP);
  *     discard internet protocol block
  *     wake up any sleepers
  */
  *     discard internet protocol block
  *     wake up any sleepers
  */

+struct tcpcb *

 tcp_close(tp)
        register struct tcpcb *tp;
 {
        register struct tcpiphdr *t;
 tcp_close(tp)
        register struct tcpcb *tp;
 {
        register struct tcpiphdr *t;

-       struct socket *so = tp->t_inpcb->inp_socket;
+       struct inpcb *inp = tp->t_inpcb;
+       struct socket *so = inp->inp_socket;
+       register struct mbuf *m;

 
 

-COUNT(TCP_CLOSE);

        t = tp->seg_next;
        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_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));
        (void) m_free(dtom(tp));

-       socantrcvmore(so);
-       socantsendmore(so);
-       in_pcbdisconnect(tp->t_inpcb);
+       inp->inp_ppcb = 0;
+       soisdisconnected(so);
+       in_pcbdetach(inp);
+       return ((struct tcpcb *)0);

 }
 
 tcp_drain()
 {
 
 }
 
 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);

 }
 }