diff options
Diffstat (limited to 'sys/netinet/tcp_input.c')
| -rw-r--r-- | sys/netinet/tcp_input.c | 68 |
1 files changed, 54 insertions, 14 deletions
diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c index 4258b00d860a..e841fac4077c 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -31,7 +31,7 @@ * SUCH DAMAGE. * * from: @(#)tcp_input.c 7.25 (Berkeley) 6/30/90 - * $Id: tcp_input.c,v 1.2 1993/10/16 18:26:26 rgrimes Exp $ + * $Id: tcp_input.c,v 1.9 1994/01/31 09:47:02 davidg Exp $ */ #include "param.h" @@ -57,16 +57,23 @@ #include "tcp_timer.h" #include "tcp_var.h" #include "tcpip.h" +#ifdef TCPDEBUG #include "tcp_debug.h" +#endif + +static void tcp_dooptions(struct tcpcb *, struct mbuf *, struct tcpiphdr *); +static void tcp_pulloutofband(struct socket *, struct tcpiphdr *, struct mbuf *); +static void tcp_xmit_timer(struct tcpcb *); int tcprexmtthresh = 3; int tcppredack; /* XXX debugging: times hdr predict ok for acks */ int tcppreddat; /* XXX # times header prediction ok for data packets */ int tcppcbcachemiss; +#ifdef TCPDEBUG struct tcpiphdr tcp_saveti; +#endif struct inpcb *tcp_last_inpcb = &tcb; -struct tcpcb *tcp_newtcpcb(); /* * Insert segment ti into reassembly queue of tcp with @@ -95,6 +102,7 @@ struct tcpcb *tcp_newtcpcb(); } \ } +int tcp_reass(tp, ti, m) register struct tcpcb *tp; register struct tcpiphdr *ti; @@ -202,6 +210,7 @@ present: * TCP input routine, follows pages 65-76 of the * protocol specification dated September, 1981 very closely. */ +void tcp_input(m, iphlen) register struct mbuf *m; int iphlen; @@ -212,12 +221,14 @@ tcp_input(m, iphlen) int len, tlen, off; register struct tcpcb *tp = 0; register int tiflags; - struct socket *so; + struct socket *so = 0; int todrop, acked, ourfinisacked, needoutput = 0; - short ostate; struct in_addr laddr; int dropsocket = 0; int iss = 0; +#ifdef TCPDEBUG + short ostate = 0; +#endif tcpstat.tcps_rcvtotal++; /* @@ -321,10 +332,12 @@ findpcb: goto drop; so = inp->inp_socket; if (so->so_options & (SO_DEBUG|SO_ACCEPTCONN)) { +#ifdef TCPDEBUG if (so->so_options & SO_DEBUG) { ostate = tp->t_state; tcp_saveti = *ti; } +#endif if (so->so_options & SO_ACCEPTCONN) { so = sonewconn(so, 0); if (so == 0) @@ -443,7 +456,17 @@ findpcb: m->m_len -= sizeof(struct tcpiphdr); sbappend(&so->so_rcv, m); sorwakeup(so); - tp->t_flags |= TF_DELACK; + /* + * If this is a small packet, then ACK now - with Nagel + * congestion avoidance sender won't send more until + * he gets an ACK. + */ + if ((unsigned)ti->ti_len < tp->t_maxseg) { + tp->t_flags |= TF_ACKNOW; + tcp_output(tp); + } else { + tp->t_flags |= TF_DELACK; + } return; } } @@ -594,7 +617,7 @@ trimthenstep6: * dropping FIN if necessary. */ ti->ti_seq++; - if (ti->ti_len > tp->rcv_wnd) { + if ((u_long)ti->ti_len > (u_long)tp->rcv_wnd) { todrop = ti->ti_len - tp->rcv_wnd; m_adj(m, -todrop); ti->ti_len = tp->rcv_wnd; @@ -1057,7 +1080,7 @@ step6: * but if two URG's are pending at once, some out-of-band * data may creep in... ick. */ - if (ti->ti_urp <= ti->ti_len + if ((u_long)ti->ti_urp <= (u_long)ti->ti_len #ifdef SO_OOBINLINE && (so->so_options & SO_OOBINLINE) == 0 #endif @@ -1144,8 +1167,18 @@ dodata: /* XXX */ break; } } +#ifdef TCPDEBUG if (so->so_options & SO_DEBUG) tcp_trace(TA_INPUT, ostate, tp, &tcp_saveti, 0); +#endif + + /* + * If this is a small packet, then ACK now - with Nagel + * congestion avoidance sender won't send more until + * he gets an ACK. + */ + if (ti->ti_len && ((unsigned)ti->ti_len < tp->t_maxseg)) + tp->t_flags |= TF_ACKNOW; /* * Return any desired output. @@ -1197,8 +1230,10 @@ drop: /* * Drop space held by incoming segment and return. */ +#ifdef TCPDEBUG if (tp && (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) tcp_trace(TA_DROP, ostate, tp, &tcp_saveti, 0); +#endif m_freem(m); /* destroy temporarily created socket */ if (dropsocket) @@ -1206,6 +1241,7 @@ drop: return; } +static void tcp_dooptions(tp, om, ti) struct tcpcb *tp; struct mbuf *om; @@ -1253,6 +1289,7 @@ tcp_dooptions(tp, om, ti) * It is still reflected in the segment length for * sequencing purposes. */ +static void tcp_pulloutofband(so, ti, m) struct socket *so; struct tcpiphdr *ti; @@ -1283,6 +1320,7 @@ tcp_pulloutofband(so, ti, m) * Collect new round-trip time estimate * and update averages and current timeout. */ +static void tcp_xmit_timer(tp) register struct tcpcb *tp; { @@ -1366,7 +1404,7 @@ tcp_xmit_timer(tp) * While looking at the routing entry, we also initialize other path-dependent * parameters from pre-set or cached values in the routing entry. */ - +int tcp_mss(tp, offer) register struct tcpcb *tp; u_short offer; @@ -1462,20 +1500,22 @@ tcp_mss(tp, offer) bufsize = so->so_snd.sb_hiwat; if (bufsize < mss) mss = bufsize; - else { + else bufsize = min(bufsize, SB_MAX) / mss * mss; - (void) sbreserve(&so->so_snd, bufsize); - } + + (void) sbreserve(&so->so_snd, bufsize); tp->t_maxseg = mss; #ifdef RTV_RPIPE if ((bufsize = rt->rt_rmx.rmx_recvpipe) == 0) #endif bufsize = so->so_rcv.sb_hiwat; - if (bufsize > mss) { + if (bufsize < mss) + bufsize = mss; + else bufsize = min(bufsize, SB_MAX) / mss * mss; - (void) sbreserve(&so->so_rcv, bufsize); - } + + (void) sbreserve(&so->so_rcv, bufsize); } tp->snd_cwnd = mss; |