Differential D30036 Diff 88739 sys/netinet/tcp_stacks/rack_bbr_common.c

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sys/netinet/tcp_stacks/rack_bbr_common.c

Context not available.
	#include <netinet/tcp_var.h>	#include <netinet/tcp_var.h>
	#include <netinet/tcpip.h>	#include <netinet/tcpip.h>
	#include <netinet/tcp_hpts.h>	#include <netinet/tcp_hpts.h>
		#include <netinet/tcp_lro.h>
	#include <netinet/cc/cc.h>	#include <netinet/cc/cc.h>
	#include <netinet/tcp_log_buf.h>	#include <netinet/tcp_log_buf.h>
	#ifdef TCPDEBUG	#ifdef TCPDEBUG
Context not available.
	}	}
	#endif	#endif

		static int
		ctf_get_enet_type(struct ifnet ifp, struct mbuf m)
		{
		struct ether_header *eh;
		struct tcphdr *th;
		#ifdef INET6
		struct ip6_hdr ip6 = NULL; / Keep compiler happy. */
		#endif
		#ifdef INET
		struct ip ip = NULL; / Keep compiler happy. */
		#endif
		int32_t tlen;
		uint16_t drop_hdrlen;
		uint16_t etype;
		uint8_t iptos;

		/* Is it the easy way? */
		if (m->m_flags & M_LRO_EHDRSTRP)
		return (m->m_pkthdr.lro_etype);
		/*
		* Ok this is the old style call, the ethernet header is here.
		* This also means no checksum or BPF were done. This
		* can happen if the race to setup the inp fails and
		* LRO sees no INP at packet input, but by the time
		* we queue the packets an INP gets there. Its rare
		* but it can occur so we will handle it. Note that
		* this means duplicated work but with the rarity of it
		* its not worth worrying about.
		*/
		/* Let the BPF see the packet */
		if (bpf_peers_present(ifp->if_bpf))
		ETHER_BPF_MTAP(ifp, m);
		/* Now the csum */
		eh = mtod(m, struct ether_header *);
		etype = ntohs(eh->ether_type);
		m_adj(m, sizeof(*eh));
		switch (etype) {
		#ifdef INET6
		case ETHERTYPE_IPV6:
		{
		if (m->m_len < (sizeof(ip6) + sizeof(th))) {
		m = m_pullup(m, sizeof(ip6) + sizeof(th));
		if (m == NULL) {
		KMOD_TCPSTAT_INC(tcps_rcvshort);
		m_freem(m);
		return (-1);
		}
		}
		ip6 = (struct ip6_hdr *)(eh + 1);
		th = (struct tcphdr *)(ip6 + 1);
		drop_hdrlen = sizeof(*ip6);
		tlen = ntohs(ip6->ip6_plen);
		if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) {
		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
		th->th_sum = m->m_pkthdr.csum_data;
		else
		th->th_sum = in6_cksum_pseudo(ip6, tlen,
		IPPROTO_TCP,
		m->m_pkthdr.csum_data);
		th->th_sum ^= 0xffff;
		} else
		th->th_sum = in6_cksum(m, IPPROTO_TCP, drop_hdrlen, tlen);
		if (th->th_sum) {
		KMOD_TCPSTAT_INC(tcps_rcvbadsum);
		m_freem(m);
		return (-1);
		}
		return (etype);
		}
		#endif
		#ifdef INET
		case ETHERTYPE_IP:
		{
		if (m->m_len < sizeof (struct tcpiphdr)) {
		m = m_pullup(m, sizeof (struct tcpiphdr));
		if (m == NULL) {
		KMOD_TCPSTAT_INC(tcps_rcvshort);
		m_freem(m);
		return (-1);
		}
		}
		ip = (struct ip *)(eh + 1);
		th = (struct tcphdr *)(ip + 1);
		drop_hdrlen = sizeof(*ip);
		iptos = ip->ip_tos;
		tlen = ntohs(ip->ip_len) - sizeof(struct ip);
		if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
		if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
		th->th_sum = m->m_pkthdr.csum_data;
		else
		th->th_sum = in_pseudo(ip->ip_src.s_addr,
		ip->ip_dst.s_addr,
		htonl(m->m_pkthdr.csum_data + tlen + IPPROTO_TCP));
		th->th_sum ^= 0xffff;
		} else {
		int len;
		struct ipovly ipov = (struct ipovly )ip;
		/*
		* Checksum extended TCP header and data.
		*/
		len = drop_hdrlen + tlen;
		bzero(ipov->ih_x1, sizeof(ipov->ih_x1));
		ipov->ih_len = htons(tlen);
		th->th_sum = in_cksum(m, len);
		/* Reset length for SDT probes. */
		ip->ip_len = htons(len);
		/* Reset TOS bits */
		ip->ip_tos = iptos;
		/* Re-initialization for later version check */
		ip->ip_v = IPVERSION;
		ip->ip_hl = sizeof(*ip) >> 2;
		}
		if (th->th_sum) {
		KMOD_TCPSTAT_INC(tcps_rcvbadsum);
		m_freem(m);
		return (-1);
		}
		break;
		}
		#endif
		};
		return (etype);
		}

	/*	/*
	* The function ctf_process_inbound_raw() is used by	* The function ctf_process_inbound_raw() is used by
	* transport developers to do the steps needed to	* transport developers to do the steps needed to
Context not available.
	* - INP_SUPPORTS_MBUFQ	* - INP_SUPPORTS_MBUFQ
	* - INP_MBUF_QUEUE_READY	* - INP_MBUF_QUEUE_READY
	* - INP_DONT_SACK_QUEUE	* - INP_DONT_SACK_QUEUE
		* - INP_MBUF_ACKCMP
	*	*
	* These flags help control how LRO will deliver	* These flags help control how LRO will deliver
	* packets to the transport. You first set in inp_flags2	* packets to the transport. You first set in inp_flags2
Context not available.
	* In some transport designs this is important since knowing	* In some transport designs this is important since knowing
	* the actual time we got the packet is useful information.	* the actual time we got the packet is useful information.
	*	*
		* A new special type of mbuf may also be supported by the transport
		* if it has set the INP_MBUF_ACKCMP flag. If its set, LRO will
		* possibly create a M_ACKCMP type mbuf. This is a mbuf with
		* an array of "acks". One thing also to note is that when this
		* occurs a subsequent LRO may find at the back of the untouched
		* mbuf queue chain a M_ACKCMP and append on to it. This means
		* that until the transport pulls in the mbuf chain queued
		* for it more ack's may get on the mbufs that were already
		* delivered. There currently is a limit of 6 acks condensed
		* into 1 mbuf which means often when this is occuring, we
		* don't get that effect but it does happen.
		*
	* Now there are some interesting Caveats that the transport	* Now there are some interesting Caveats that the transport
	* designer needs to take into account when using this feature.	* designer needs to take into account when using this feature.
	*	*
Context not available.
	* shipped in, the tcb has been destroyed (or about to be destroyed).	* shipped in, the tcb has been destroyed (or about to be destroyed).
	*/	*/
	struct mbuf *m_save;	struct mbuf *m_save;
	struct ether_header *eh;
	struct tcphdr *th;	struct tcphdr *th;
	#ifdef INET6	#ifdef INET6
	struct ip6_hdr ip6 = NULL; / Keep compiler happy. */	struct ip6_hdr ip6 = NULL; / Keep compiler happy. */
Context not available.
	#endif	#endif
	struct ifnet *ifp;	struct ifnet *ifp;
	struct timeval tv;	struct timeval tv;
		struct inpcb *inp;
	int32_t retval, nxt_pkt, tlen, off;	int32_t retval, nxt_pkt, tlen, off;
	uint16_t etype;	int etype = 0;
	uint16_t drop_hdrlen;	uint16_t drop_hdrlen;
	uint8_t iptos, no_vn=0, bpf_req=0;	uint8_t iptos, no_vn=0;

	NET_EPOCH_ASSERT();	NET_EPOCH_ASSERT();
		if (m)
	if (m && m->m_pkthdr.rcvif)	ifp = m_rcvif(m);
	ifp = m->m_pkthdr.rcvif;
	else	else
	ifp = NULL;	ifp = NULL;
	if (ifp) {	if (ifp == NULL) {
	bpf_req = bpf_peers_present(ifp->if_bpf);
	} else {
	/*	/*
	* We probably should not work around	* We probably should not work around
	* but kassert, since lro alwasy sets rcvif.	* but kassert, since lro alwasy sets rcvif.
Context not available.
	}	}
	CURVNET_SET(ifp->if_vnet);	CURVNET_SET(ifp->if_vnet);
	skip_vnet:	skip_vnet:
		tcp_get_usecs(&tv);
	while (m) {	while (m) {
	m_save = m->m_nextpkt;	m_save = m->m_nextpkt;
	m->m_nextpkt = NULL;	m->m_nextpkt = NULL;
	/* Now lets get the ether header */	if ((m->m_flags & M_ACKCMP) == 0) {
	eh = mtod(m, struct ether_header *);	/* Now lets get the ether header */
	etype = ntohs(eh->ether_type);	etype = ctf_get_enet_type(ifp, m);
	/* Let the BPF see the packet */	if (etype == -1) {
	if (bpf_req && ifp)	/* Skip this packet it was freed by checksum */
	ETHER_BPF_MTAP(ifp, m);
	m_adj(m, sizeof(*eh));
	/* Trim off the ethernet header */
	switch (etype) {
	#ifdef INET6
	case ETHERTYPE_IPV6:
	{
	if (m->m_len < (sizeof(ip6) + sizeof(th))) {
	m = m_pullup(m, sizeof(ip6) + sizeof(th));
	if (m == NULL) {
	KMOD_TCPSTAT_INC(tcps_rcvshort);
	m_freem(m);
	goto skipped_pkt;
	}
	}
	ip6 = (struct ip6_hdr *)(eh + 1);
	th = (struct tcphdr *)(ip6 + 1);
	tlen = ntohs(ip6->ip6_plen);
	drop_hdrlen = sizeof(*ip6);
	if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID_IPV6) {
	if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
	th->th_sum = m->m_pkthdr.csum_data;
	else
	th->th_sum = in6_cksum_pseudo(ip6, tlen,
	IPPROTO_TCP, m->m_pkthdr.csum_data);
	th->th_sum ^= 0xffff;
	} else
	th->th_sum = in6_cksum(m, IPPROTO_TCP, drop_hdrlen, tlen);
	if (th->th_sum) {
	KMOD_TCPSTAT_INC(tcps_rcvbadsum);
	m_freem(m);
	goto skipped_pkt;
	}
	/*
	* Be proactive about unspecified IPv6 address in source.
	* As we use all-zero to indicate unbounded/unconnected pcb,
	* unspecified IPv6 address can be used to confuse us.
	*
	* Note that packets with unspecified IPv6 destination is
	* already dropped in ip6_input.
	*/
	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
	/* XXX stat */
	m_freem(m);
	goto skipped_pkt;	goto skipped_pkt;
	}	}
	iptos = IPV6_TRAFFIC_CLASS(ip6);	KASSERT(((etype == ETHERTYPE_IPV6) \|\| (etype == ETHERTYPE_IP)),
	break;	("tp:%p m:%p etype:0x%x -- not IP or IPv6", tp, m, etype));
	}	/* Trim off the ethernet header */
		switch (etype) {
		#ifdef INET6
		case ETHERTYPE_IPV6:
		ip6 = mtod(m, struct ip6_hdr *);
		th = (struct tcphdr *)(ip6 + 1);
		tlen = ntohs(ip6->ip6_plen);
		drop_hdrlen = sizeof(*ip6);
		iptos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
		break;
	#endif	#endif
	#ifdef INET	#ifdef INET
	case ETHERTYPE_IP:	case ETHERTYPE_IP:
	{	ip = mtod(m, struct ip *);
	if (m->m_len < sizeof (struct tcpiphdr)) {	th = (struct tcphdr *)(ip + 1);
	if ((m = m_pullup(m, sizeof (struct tcpiphdr)))	drop_hdrlen = sizeof(*ip);
	== NULL) {	iptos = ip->ip_tos;
	KMOD_TCPSTAT_INC(tcps_rcvshort);	tlen = ntohs(ip->ip_len) - sizeof(struct ip);
	m_freem(m);	break;
	goto skipped_pkt;
	}
	}
	ip = (struct ip *)(eh + 1);
	th = (struct tcphdr *)(ip + 1);
	drop_hdrlen = sizeof(*ip);
	iptos = ip->ip_tos;
	tlen = ntohs(ip->ip_len) - sizeof(struct ip);
	if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
	if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
	th->th_sum = m->m_pkthdr.csum_data;
	else
	th->th_sum = in_pseudo(ip->ip_src.s_addr,
	ip->ip_dst.s_addr,
	htonl(m->m_pkthdr.csum_data + tlen +
	IPPROTO_TCP));
	th->th_sum ^= 0xffff;
	} else {
	int len;
	struct ipovly ipov = (struct ipovly )ip;
	/*
	* Checksum extended TCP header and data.
	*/
	len = drop_hdrlen + tlen;
	bzero(ipov->ih_x1, sizeof(ipov->ih_x1));
	ipov->ih_len = htons(tlen);
	th->th_sum = in_cksum(m, len);
	/* Reset length for SDT probes. */
	ip->ip_len = htons(len);
	/* Reset TOS bits */
	ip->ip_tos = iptos;
	/* Re-initialization for later version check */
	ip->ip_v = IPVERSION;
	ip->ip_hl = sizeof(*ip) >> 2;
	}
	if (th->th_sum) {
	KMOD_TCPSTAT_INC(tcps_rcvbadsum);
	m_freem(m);
	goto skipped_pkt;
	}
	break;
	}
	#endif	#endif
	}	} /* end switch */
	/*	/*
	* Convert TCP protocol specific fields to host format.	* Convert TCP protocol specific fields to host format.
	*/	*/
	tcp_fields_to_host(th);	tcp_fields_to_host(th);
		off = th->th_off << 2;
	off = th->th_off << 2;	if (off < sizeof (struct tcphdr) \|\| off > tlen) {
	if (off < sizeof (struct tcphdr) \|\| off > tlen) {	printf("off:%d < hdrlen:%zu \|\| > tlen:%u -- dump\n",
	KMOD_TCPSTAT_INC(tcps_rcvbadoff);	off,
		sizeof(struct tcphdr),
		tlen);
		KMOD_TCPSTAT_INC(tcps_rcvbadoff);
	m_freem(m);	m_freem(m);
	goto skipped_pkt;	goto skipped_pkt;
	}	}
	tlen -= off;	tlen -= off;
	drop_hdrlen += off;	drop_hdrlen += off;
	/*	/*
	* Now lets setup the timeval to be when we should	* Now lets setup the timeval to be when we should
	* have been called (if we can).	* have been called (if we can).
	*/	*/
	m->m_pkthdr.lro_nsegs = 1;	m->m_pkthdr.lro_nsegs = 1;
	if (m->m_flags & M_TSTMP_LRO) {	/* Now what about next packet? */
	tv.tv_sec = m->m_pkthdr.rcv_tstmp /1000000000;
	tv.tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000)/1000;
	} else {	} else {
	/* Should not be should we kassert instead? */	/*
	tcp_get_usecs(&tv);	* This mbuf is an array of acks that have
		* been compressed. We assert the inp has
		* the flag set to enable this!
		*/
		KASSERT((tp->t_inpcb->inp_flags2 & INP_MBUF_ACKCMP),
		("tp:%p inp:%p no INP_MBUF_ACKCMP flags?", tp, tp->t_inpcb));
		tlen = 0;
		drop_hdrlen = 0;
		th = NULL;
		iptos = 0;
	}	}
	/* Now what about next packet? */	tcp_get_usecs(&tv);
	if (m_save \|\| has_pkt)	if (m_save \|\| has_pkt)
	nxt_pkt = 1;	nxt_pkt = 1;
	else	else
	nxt_pkt = 0;	nxt_pkt = 0;
	KMOD_TCPSTAT_INC(tcps_rcvtotal);	if ((m->m_flags & M_ACKCMP) == 0)
		KMOD_TCPSTAT_INC(tcps_rcvtotal);
		else
		KMOD_TCPSTAT_ADD(tcps_rcvtotal, (m->m_len / sizeof(struct tcp_ackent)));
		inp = tp->t_inpcb;
		INP_WLOCK_ASSERT(inp);
	retval = (*tp->t_fb->tfb_do_segment_nounlock)(m, th, so, tp, drop_hdrlen, tlen,	retval = (*tp->t_fb->tfb_do_segment_nounlock)(m, th, so, tp, drop_hdrlen, tlen,
	iptos, nxt_pkt, &tv);	iptos, nxt_pkt, &tv);
	if (retval) {	if (retval) {
Context not available.
	}	}
	if (no_vn == 0)	if (no_vn == 0)
	CURVNET_RESTORE();	CURVNET_RESTORE();
		INP_UNLOCK_ASSERT(inp);
	return(retval);	return(retval);
	}	}
	skipped_pkt:	skipped_pkt:
Context not available.
	if (rc_sacked <= ctf_outstanding(tp))	if (rc_sacked <= ctf_outstanding(tp))
	return(ctf_outstanding(tp) - rc_sacked);	return(ctf_outstanding(tp) - rc_sacked);
	else {	else {
	/* TSNH */
	#ifdef INVARIANTS
	panic("tp:%p rc_sacked:%d > out:%d",
	tp, rc_sacked, ctf_outstanding(tp));
	#endif
	return (0);	return (0);
	}	}
	}	}
Context not available.
	tcp_dropwithreset(m, th, NULL, tlen, rstreason);	tcp_dropwithreset(m, th, NULL, tlen, rstreason);
	}	}

		void
		ctf_ack_war_checks(struct tcpcb tp, uint32_t ts, uint32_t *cnt)
		{
		if ((ts != NULL) && (cnt != NULL) &&
		(tcp_ack_war_time_window > 0) &&
		(tcp_ack_war_cnt > 0)) {
		/* We are possibly doing ack war prevention */
		uint32_t cts;

		/*
		* We use a msec tick here which gives us
		* roughly 49 days. We don't need the
		* precision of a microsecond timestamp which
		* would only give us hours.
		*/
		cts = tcp_ts_getticks();
		if (TSTMP_LT((*ts), cts)) {
		/* Timestamp is in the past */
		*cnt = 0;
		*ts = (cts + tcp_ack_war_time_window);
		}
		if (*cnt < tcp_ack_war_cnt) {
		cnt = (cnt + 1);
		tp->t_flags \|= TF_ACKNOW;
		} else
		tp->t_flags &= ~TF_ACKNOW;
		} else
		tp->t_flags \|= TF_ACKNOW;
		}

	/*	/*
	* ctf_drop_checks returns 1 for you should not proceed. It places	* ctf_drop_checks returns 1 for you should not proceed. It places
	* in ret_val what should be returned 1/0 by the caller. The 1 indicates	* in ret_val what should be returned 1/0 by the caller. The 1 indicates
Context not available.
	* TCB is still valid and locked.	* TCB is still valid and locked.
	*/	*/
	int	int
	ctf_drop_checks(struct tcpopt to, struct mbuf m, struct tcphdr th, struct tcpcb tp, int32_t * tlenp, int32_t * thf, int32_t * drop_hdrlen, int32_t * ret_val)	_ctf_drop_checks(struct tcpopt to, struct mbuf m, struct tcphdr *th,
		struct tcpcb tp, int32_t tlenp,
		int32_t thf, int32_t drop_hdrlen, int32_t *ret_val,
		uint32_t ts, uint32_t cnt)
	{	{
	int32_t todrop;	int32_t todrop;
	int32_t thflags;	int32_t thflags;
Context not available.
	* Send an ACK to resynchronize and drop any data.	* Send an ACK to resynchronize and drop any data.
	* But keep on processing for RST or ACK.	* But keep on processing for RST or ACK.
	*/	*/
	tp->t_flags \|= TF_ACKNOW;	ctf_ack_war_checks(tp, ts, cnt);
	todrop = tlen;	todrop = tlen;
	KMOD_TCPSTAT_INC(tcps_rcvduppack);	KMOD_TCPSTAT_INC(tcps_rcvduppack);
	KMOD_TCPSTAT_ADD(tcps_rcvdupbyte, todrop);	KMOD_TCPSTAT_ADD(tcps_rcvdupbyte, todrop);
Context not available.
	* DSACK - add SACK block for dropped range	* DSACK - add SACK block for dropped range
	*/	*/
	if ((todrop > 0) && (tp->t_flags & TF_SACK_PERMIT)) {	if ((todrop > 0) && (tp->t_flags & TF_SACK_PERMIT)) {
	tcp_update_sack_list(tp, th->th_seq,
	th->th_seq + todrop);
	/*	/*
	* ACK now, as the next in-sequence segment	* ACK now, as the next in-sequence segment
	* will clear the DSACK block again	* will clear the DSACK block again
	*/	*/
	tp->t_flags \|= TF_ACKNOW;	ctf_ack_war_checks(tp, ts, cnt);
		if (tp->t_flags & TF_ACKNOW)
		tcp_update_sack_list(tp, th->th_seq,
		th->th_seq + todrop);
	}	}
	drop_hdrlen += todrop; / drop from the top afterwards */	drop_hdrlen += todrop; / drop from the top afterwards */
	th->th_seq += todrop;	th->th_seq += todrop;
Context not available.
	* ack.	* ack.
	*/	*/
	if (tp->rcv_wnd == 0 && th->th_seq == tp->rcv_nxt) {	if (tp->rcv_wnd == 0 && th->th_seq == tp->rcv_nxt) {
	tp->t_flags \|= TF_ACKNOW;	ctf_ack_war_checks(tp, ts, cnt);
	KMOD_TCPSTAT_INC(tcps_rcvwinprobe);	KMOD_TCPSTAT_INC(tcps_rcvwinprobe);
	} else {	} else {
	ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val);	__ctf_do_dropafterack(m, tp, th, thflags, tlen, ret_val, ts, cnt);
	return (1);	return (1);
	}	}
	} else	} else
Context not available.
	* and valid.	* and valid.
	*/	*/
	void	void
	ctf_do_dropafterack(struct mbuf m, struct tcpcb tp, struct tcphdr th, int32_t thflags, int32_t tlen, int32_t ret_val)	__ctf_do_dropafterack(struct mbuf m, struct tcpcb tp, struct tcphdr th, int32_t thflags, int32_t tlen, int32_t ret_val, uint32_t ts, uint32_t cnt)
	{	{
	/*	/*
	* Generate an ACK dropping incoming segment if it occupies sequence	* Generate an ACK dropping incoming segment if it occupies sequence
Context not available.
	return;	return;
	} else	} else
	*ret_val = 0;	*ret_val = 0;
	tp->t_flags \|= TF_ACKNOW;	ctf_ack_war_checks(tp, ts, cnt);
	if (m)	if (m)
	m_freem(m);	m_freem(m);
	}	}
Context not available.
	*/	*/
	int dropped = 0;	int dropped = 0;

	if ((SEQ_GEQ(th->th_seq, (tp->last_ack_sent - 1)) &&	if ((SEQ_GEQ(th->th_seq, tp->last_ack_sent) &&
	SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) \|\|	SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) \|\|
	(tp->rcv_wnd == 0 && tp->last_ack_sent == th->th_seq)) {	(tp->rcv_wnd == 0 && tp->last_ack_sent == th->th_seq)) {
	KASSERT(tp->t_state != TCPS_SYN_SENT,	KASSERT(tp->t_state != TCPS_SYN_SENT,
Context not available.

	if (V_tcp_insecure_rst \|\|	if (V_tcp_insecure_rst \|\|
	(tp->last_ack_sent == th->th_seq) \|\|	(tp->last_ack_sent == th->th_seq) \|\|
	(tp->rcv_nxt == th->th_seq) \|\|	(tp->rcv_nxt == th->th_seq)) {
	((tp->last_ack_sent - 1) == th->th_seq)) {
	KMOD_TCPSTAT_INC(tcps_drops);	KMOD_TCPSTAT_INC(tcps_drops);
	/* Drop the connection. */	/* Drop the connection. */
	switch (tp->t_state) {	switch (tp->t_state) {
Context not available.
	}	}

	/*	/*
	* bbr_ts_check returns 1 for you should not proceed, the state	* ctf_ts_check returns 1 for you should not proceed, the state
	* machine should return. It places in ret_val what should	* machine should return. It places in ret_val what should
	* be returned 1/0 by the caller (hpts_do_segment). The 1 indicates	* be returned 1/0 by the caller (hpts_do_segment). The 1 indicates
	* that the TCB is unlocked and probably dropped. The 0 indicates the	* that the TCB is unlocked and probably dropped. The 0 indicates the
Context not available.
	return (0);	return (0);
	}	}

		int
		ctf_ts_check_ac(struct tcpcb *tp, int32_t thflags)
		{

		if (tcp_ts_getticks() - tp->ts_recent_age > TCP_PAWS_IDLE) {
		/*
		* Invalidate ts_recent. If this segment updates ts_recent,
		* the age will be reset later and ts_recent will get a
		* valid value. If it does not, setting ts_recent to zero
		* will at least satisfy the requirement that zero be placed
		* in the timestamp echo reply when ts_recent isn't valid.
		* The age isn't reset until we get a valid ts_recent
		* because we don't want out-of-order segments to be dropped
		* when ts_recent is old.
		*/
		tp->ts_recent = 0;
		} else {
		KMOD_TCPSTAT_INC(tcps_rcvduppack);
		KMOD_TCPSTAT_INC(tcps_pawsdrop);
		return (1);
		}
		return (0);
		}



	void	void
	ctf_calc_rwin(struct socket so, struct tcpcb tp)	ctf_calc_rwin(struct socket so, struct tcpcb tp)
	{	{
Context not available.
	uint32_t	uint32_t
	ctf_fixed_maxseg(struct tcpcb *tp)	ctf_fixed_maxseg(struct tcpcb *tp)
	{	{
	int optlen;	return (tcp_fixed_maxseg(tp));

	if (tp->t_flags & TF_NOOPT)
	return (tp->t_maxseg);

	/*
	* Here we have a simplified code from tcp_addoptions(),
	* without a proper loop, and having most of paddings hardcoded.
	* We only consider fixed options that we would send every
	* time I.e. SACK is not considered.
	*
	*/
	#define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4)
	if (TCPS_HAVEESTABLISHED(tp->t_state)) {
	if (tp->t_flags & TF_RCVD_TSTMP)
	optlen = TCPOLEN_TSTAMP_APPA;
	else
	optlen = 0;
	#if defined(IPSEC_SUPPORT) \|\| defined(TCP_SIGNATURE)
	if (tp->t_flags & TF_SIGNATURE)
	optlen += PAD(TCPOLEN_SIGNATURE);
	#endif
	} else {
	if (tp->t_flags & TF_REQ_TSTMP)
	optlen = TCPOLEN_TSTAMP_APPA;
	else
	optlen = PAD(TCPOLEN_MAXSEG);
	if (tp->t_flags & TF_REQ_SCALE)
	optlen += PAD(TCPOLEN_WINDOW);
	#if defined(IPSEC_SUPPORT) \|\| defined(TCP_SIGNATURE)
	if (tp->t_flags & TF_SIGNATURE)
	optlen += PAD(TCPOLEN_SIGNATURE);
	#endif
	if (tp->t_flags & TF_SACK_PERMIT)
	optlen += PAD(TCPOLEN_SACK_PERMITTED);
	}
	#undef PAD
	optlen = min(optlen, TCP_MAXOLEN);
	return (tp->t_maxseg - optlen);
	}	}

	void	void
Context not available.