Complete the (mechanical) move of the TCP reassembly and timewait

functions from their origininal place to their own files.

TCP Reassembly from tcp_input.c -> tcp_reass.c
TCP Timewait   from tcp_subr.c  -> tcp_timewait.c

1 files changed, 2 insertions, 352 deletions

diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index 90c2aba..8d2e8e4 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -162,52 +162,6 @@ static int	tcp_isn_reseed_interval = 0;
 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW,
     &tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret");
 
-static uma_zone_t tcptw_zone;
-static int	maxtcptw;
-
-static int
-tcptw_auto_size(void)
-{
-	int halfrange;
-
-	/*
-	 * Max out at half the ephemeral port range so that TIME_WAIT
-	 * sockets don't tie up too many ephemeral ports.
-	 */
-	if (ipport_lastauto > ipport_firstauto)
-		halfrange = (ipport_lastauto - ipport_firstauto) / 2;
-	else
-		halfrange = (ipport_firstauto - ipport_lastauto) / 2;
-	/* Protect against goofy port ranges smaller than 32. */
-	return (imin(imax(halfrange, 32), maxsockets / 5));
-}
-
-static int
-sysctl_maxtcptw(SYSCTL_HANDLER_ARGS)
-{
-	int error, new;
-
-	if (maxtcptw == 0)
-		new = tcptw_auto_size();
-	else
-		new = maxtcptw;
-	error = sysctl_handle_int(oidp, &new, sizeof(int), req);
-	if (error == 0 && req->newptr)
-		if (new >= 32) {
-			maxtcptw = new;
-			uma_zone_set_max(tcptw_zone, maxtcptw);
-		}
-	return (error);
-}
-SYSCTL_PROC(_net_inet_tcp, OID_AUTO, maxtcptw, CTLTYPE_INT|CTLFLAG_RW,
-    &maxtcptw, 0, sysctl_maxtcptw, "IU",
-    "Maximum number of compressed TCP TIME_WAIT entries");
-
-static int	nolocaltimewait = 0;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, nolocaltimewait, CTLFLAG_RW,
-    &nolocaltimewait, 0,
-    "Do not create compressed TCP TIME_WAIT entries for local connections");
-
 /*
  * TCP bandwidth limiting sysctls.  Note that the default lower bound of
  * 1024 exists only for debugging.  A good production default would be
@@ -284,8 +238,7 @@ tcp_zone_change(void *tag)
 
 	uma_zone_set_max(tcbinfo.ipi_zone, maxsockets);
 	uma_zone_set_max(tcpcb_zone, maxsockets);
-	if (maxtcptw == 0)
-		uma_zone_set_max(tcptw_zone, tcptw_auto_size());
+	tcp_tw_zone_change();
 }
 
 static int
@@ -345,14 +298,8 @@ tcp_init(void)
 	tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem),
 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
 	uma_zone_set_max(tcpcb_zone, maxsockets);
-	tcptw_zone = uma_zcreate("tcptw", sizeof(struct tcptw),
-	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
-	TUNABLE_INT_FETCH("net.inet.tcp.maxtcptw", &maxtcptw);
-	if (maxtcptw == 0)
-		uma_zone_set_max(tcptw_zone, tcptw_auto_size());
-	else
-		uma_zone_set_max(tcptw_zone, maxtcptw);
 	tcp_timer_init();
+	tcp_tw_init();
 	syncache_init();
 	tcp_hc_init();
 	tcp_reass_init();
@@ -1742,303 +1689,6 @@ ipsec_hdrsiz_tcp(struct tcpcb *tp)
 #endif /*IPSEC*/
 
 /*
- * Move a TCP connection into TIME_WAIT state.
- *    tcbinfo is locked.
- *    inp is locked, and is unlocked before returning.
- */
-void
-tcp_twstart(struct tcpcb *tp)
-{
-	struct tcptw *tw;
-	struct inpcb *inp = tp->t_inpcb;
-	int acknow;
-	struct socket *so;
-
-	INP_INFO_WLOCK_ASSERT(&tcbinfo);	/* tcp_timer_2msl_reset(). */
-	INP_LOCK_ASSERT(inp);
-
-	if (nolocaltimewait && in_localip(inp->inp_faddr)) {
-		tp = tcp_close(tp);
-		if (tp != NULL)
-			INP_UNLOCK(inp);
-		return;
-	}
-
-	tw = uma_zalloc(tcptw_zone, M_NOWAIT);
-	if (tw == NULL) {
-		tw = tcp_timer_2msl_tw(1);
-		if (tw == NULL) {
-			tp = tcp_close(tp);
-			if (tp != NULL)
-				INP_UNLOCK(inp);
-			return;
-		}
-	}
-	tw->tw_inpcb = inp;
-
-	/*
-	 * Recover last window size sent.
-	 */
-	tw->last_win = (tp->rcv_adv - tp->rcv_nxt) >> tp->rcv_scale;
-
-	/*
-	 * Set t_recent if timestamps are used on the connection.
-	 */
-	if ((tp->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP|TF_NOOPT)) ==
-	    (TF_REQ_TSTMP|TF_RCVD_TSTMP)) {
-		tw->t_recent = tp->ts_recent;
-		tw->ts_offset = tp->ts_offset;
-	} else {
-		tw->t_recent = 0;
-		tw->ts_offset = 0;
-	}
-
-	tw->snd_nxt = tp->snd_nxt;
-	tw->rcv_nxt = tp->rcv_nxt;
-	tw->iss     = tp->iss;
-	tw->irs     = tp->irs;
-	tw->t_starttime = tp->t_starttime;
-	tw->tw_time = 0;
-
-/* XXX
- * If this code will
- * be used for fin-wait-2 state also, then we may need
- * a ts_recent from the last segment.
- */
-	acknow = tp->t_flags & TF_ACKNOW;
-
-	/*
-	 * First, discard tcpcb state, which includes stopping its timers and
-	 * freeing it.  tcp_discardcb() used to also release the inpcb, but
-	 * that work is now done in the caller.
-	 *
-	 * Note: soisdisconnected() call used to be made in tcp_discardcb(),
-	 * and might not be needed here any longer.
-	 */
-	tcp_discardcb(tp);
-	so = inp->inp_socket;
-	soisdisconnected(so);
-	tw->tw_cred = crhold(so->so_cred);
-	SOCK_LOCK(so);
-	tw->tw_so_options = so->so_options;
-	SOCK_UNLOCK(so);
-	if (acknow)
-		tcp_twrespond(tw, TH_ACK);
-	inp->inp_ppcb = tw;
-	inp->inp_vflag |= INP_TIMEWAIT;
-	tcp_timer_2msl_reset(tw, 0);
-
-	/*
-	 * If the inpcb owns the sole reference to the socket, then we can
-	 * detach and free the socket as it is not needed in time wait.
-	 */
-	if (inp->inp_vflag & INP_SOCKREF) {
-		KASSERT(so->so_state & SS_PROTOREF,
-		    ("tcp_twstart: !SS_PROTOREF"));
-		inp->inp_vflag &= ~INP_SOCKREF;
-		INP_UNLOCK(inp);
-		ACCEPT_LOCK();
-		SOCK_LOCK(so);
-		so->so_state &= ~SS_PROTOREF;
-		sofree(so);
-	} else
-		INP_UNLOCK(inp);
-}
-
-#if 0
-/*
- * The appromixate rate of ISN increase of Microsoft TCP stacks;
- * the actual rate is slightly higher due to the addition of
- * random positive increments.
- *
- * Most other new OSes use semi-randomized ISN values, so we
- * do not need to worry about them.
- */
-#define MS_ISN_BYTES_PER_SECOND		250000
-
-/*
- * Determine if the ISN we will generate has advanced beyond the last
- * sequence number used by the previous connection.  If so, indicate
- * that it is safe to recycle this tw socket by returning 1.
- */
-int
-tcp_twrecycleable(struct tcptw *tw)
-{
-	tcp_seq new_iss = tw->iss;
-	tcp_seq new_irs = tw->irs;
-
-	INP_INFO_WLOCK_ASSERT(&tcbinfo);
-	new_iss += (ticks - tw->t_starttime) * (ISN_BYTES_PER_SECOND / hz);
-	new_irs += (ticks - tw->t_starttime) * (MS_ISN_BYTES_PER_SECOND / hz);
-
-	if (SEQ_GT(new_iss, tw->snd_nxt) && SEQ_GT(new_irs, tw->rcv_nxt))
-		return (1);
-	else
-		return (0);
-}
-#endif
-
-void
-tcp_twclose(struct tcptw *tw, int reuse)
-{
-	struct socket *so;
-	struct inpcb *inp;
-
-	/*
-	 * At this point, we are in one of two situations:
-	 *
-	 * (1) We have no socket, just an inpcb<->twtcp pair.  We can free
-	 *     all state.
-	 *
-	 * (2) We have a socket -- if we own a reference, release it and
-	 *     notify the socket layer.
-	 */
-	inp = tw->tw_inpcb;
-	KASSERT((inp->inp_vflag & INP_TIMEWAIT), ("tcp_twclose: !timewait"));
-	KASSERT(intotw(inp) == tw, ("tcp_twclose: inp_ppcb != tw"));
-	INP_INFO_WLOCK_ASSERT(&tcbinfo);	/* tcp_timer_2msl_stop(). */
-	INP_LOCK_ASSERT(inp);
-
-	tw->tw_inpcb = NULL;
-	tcp_timer_2msl_stop(tw);
-	inp->inp_ppcb = NULL;
-	in_pcbdrop(inp);
-
-	so = inp->inp_socket;
-	if (so != NULL) {
-		/*
-		 * If there's a socket, handle two cases: first, we own a
-		 * strong reference, which we will now release, or we don't
-		 * in which case another reference exists (XXXRW: think
-		 * about this more), and we don't need to take action.
-		 */
-		if (inp->inp_vflag & INP_SOCKREF) {
-			inp->inp_vflag &= ~INP_SOCKREF;
-			INP_UNLOCK(inp);
-			ACCEPT_LOCK();
-			SOCK_LOCK(so);
-			KASSERT(so->so_state & SS_PROTOREF,
-			    ("tcp_twclose: INP_SOCKREF && !SS_PROTOREF"));
-			so->so_state &= ~SS_PROTOREF;
-			sofree(so);
-		} else {
-			/*
-			 * If we don't own the only reference, the socket and
-			 * inpcb need to be left around to be handled by
-			 * tcp_usr_detach() later.
-			 */
-			INP_UNLOCK(inp);
-		}
-	} else {
-#ifdef INET6
-		if (inp->inp_vflag & INP_IPV6PROTO)
-			in6_pcbfree(inp);
-		else
-#endif
-			in_pcbfree(inp);
-	}
-	tcpstat.tcps_closed++;
-	crfree(tw->tw_cred);
-	tw->tw_cred = NULL;
-	if (reuse)
-		return;
-	uma_zfree(tcptw_zone, tw);
-}
-
-int
-tcp_twrespond(struct tcptw *tw, int flags)
-{
-	struct inpcb *inp = tw->tw_inpcb;
-	struct tcphdr *th;
-	struct mbuf *m;
-	struct ip *ip = NULL;
-	u_int hdrlen, optlen;
-	int error;
-	struct tcpopt to;
-#ifdef INET6
-	struct ip6_hdr *ip6 = NULL;
-	int isipv6 = inp->inp_inc.inc_isipv6;
-#endif
-
-	INP_LOCK_ASSERT(inp);
-
-	m = m_gethdr(M_DONTWAIT, MT_DATA);
-	if (m == NULL)
-		return (ENOBUFS);
-	m->m_data += max_linkhdr;
-
-#ifdef MAC
-	mac_create_mbuf_from_inpcb(inp, m);
-#endif
-
-#ifdef INET6
-	if (isipv6) {
-		hdrlen = sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
-		ip6 = mtod(m, struct ip6_hdr *);
-		th = (struct tcphdr *)(ip6 + 1);
-		tcpip_fillheaders(inp, ip6, th);
-	} else
-#endif
-	{
-		hdrlen = sizeof(struct tcpiphdr);
-		ip = mtod(m, struct ip *);
-		th = (struct tcphdr *)(ip + 1);
-		tcpip_fillheaders(inp, ip, th);
-	}
-	to.to_flags = 0;
-
-	/*
-	 * Send a timestamp and echo-reply if both our side and our peer
-	 * have sent timestamps in our SYN's and this is not a RST.
-	 */
-	if (tw->t_recent && flags == TH_ACK) {
-		to.to_flags |= TOF_TS;
-		to.to_tsval = ticks + tw->ts_offset;
-		to.to_tsecr = tw->t_recent;
-	}
-	optlen = tcp_addoptions(&to, (u_char *)(th + 1));
-
-	m->m_len = hdrlen + optlen;
-	m->m_pkthdr.len = m->m_len;
-
-	KASSERT(max_linkhdr + m->m_len <= MHLEN, ("tcptw: mbuf too small"));
-
-	th->th_seq = htonl(tw->snd_nxt);
-	th->th_ack = htonl(tw->rcv_nxt);
-	th->th_off = (sizeof(struct tcphdr) + optlen) >> 2;
-	th->th_flags = flags;
-	th->th_win = htons(tw->last_win);
-
-#ifdef INET6
-	if (isipv6) {
-		th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(struct ip6_hdr),
-		    sizeof(struct tcphdr) + optlen);
-		ip6->ip6_hlim = in6_selecthlim(inp, NULL);
-		error = ip6_output(m, inp->in6p_outputopts, NULL,
-		    (tw->tw_so_options & SO_DONTROUTE), NULL, NULL, inp);
-	} else
-#endif
-	{
-		th->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
-		    htons(sizeof(struct tcphdr) + optlen + IPPROTO_TCP));
-		m->m_pkthdr.csum_flags = CSUM_TCP;
-		m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
-		ip->ip_len = m->m_pkthdr.len;
-		if (path_mtu_discovery)
-			ip->ip_off |= IP_DF;
-		error = ip_output(m, inp->inp_options, NULL,
-		    ((tw->tw_so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0),
-		    NULL, inp);
-	}
-	if (flags & TH_ACK)
-		tcpstat.tcps_sndacks++;
-	else
-		tcpstat.tcps_sndctrl++;
-	tcpstat.tcps_sndtotal++;
-	return (error);
-}
-
-/*
  * TCP BANDWIDTH DELAY PRODUCT WINDOW LIMITING
  *
  * This code attempts to calculate the bandwidth-delay product as a