TCPSpeedTest - I have a problem getting this to work. Server onl…

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Jesper Taxbøl / Mbed 2 deprecated TCPSpeedTest

I have a problem getting this to work. Server only recieves half of the data being sent. Whats wrong

lwip/core/tcp_in.c@0:66300c77c6e9, 2011-03-29 (annotated)

Committer:: tax
Date:: Tue Mar 29 13:20:15 2011 +0000
Revision:: 0:66300c77c6e9

Who changed what in which revision?

User	Revision	Line number	New contents of line
tax	0:66300c77c6e9	1	/**
tax	0:66300c77c6e9	2	* @file
tax	0:66300c77c6e9	3	* Transmission Control Protocol, incoming traffic
tax	0:66300c77c6e9	4	*
tax	0:66300c77c6e9	5	* The input processing functions of the TCP layer.
tax	0:66300c77c6e9	6	*
tax	0:66300c77c6e9	7	* These functions are generally called in the order (ip_input() ->)
tax	0:66300c77c6e9	8	* tcp_input() -> * tcp_process() -> tcp_receive() (-> application).
tax	0:66300c77c6e9	9	*
tax	0:66300c77c6e9	10	*/
tax	0:66300c77c6e9	11
tax	0:66300c77c6e9	12	/*
tax	0:66300c77c6e9	13	* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
tax	0:66300c77c6e9	14	* All rights reserved.
tax	0:66300c77c6e9	15	*
tax	0:66300c77c6e9	16	* Redistribution and use in source and binary forms, with or without modification,
tax	0:66300c77c6e9	17	* are permitted provided that the following conditions are met:
tax	0:66300c77c6e9	18	*
tax	0:66300c77c6e9	19	* 1. Redistributions of source code must retain the above copyright notice,
tax	0:66300c77c6e9	20	* this list of conditions and the following disclaimer.
tax	0:66300c77c6e9	21	* 2. Redistributions in binary form must reproduce the above copyright notice,
tax	0:66300c77c6e9	22	* this list of conditions and the following disclaimer in the documentation
tax	0:66300c77c6e9	23	* and/or other materials provided with the distribution.
tax	0:66300c77c6e9	24	* 3. The name of the author may not be used to endorse or promote products
tax	0:66300c77c6e9	25	* derived from this software without specific prior written permission.
tax	0:66300c77c6e9	26	*
tax	0:66300c77c6e9	27	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
tax	0:66300c77c6e9	28	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
tax	0:66300c77c6e9	29	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
tax	0:66300c77c6e9	30	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
tax	0:66300c77c6e9	31	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
tax	0:66300c77c6e9	32	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
tax	0:66300c77c6e9	33	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
tax	0:66300c77c6e9	34	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
tax	0:66300c77c6e9	35	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
tax	0:66300c77c6e9	36	* OF SUCH DAMAGE.
tax	0:66300c77c6e9	37	*
tax	0:66300c77c6e9	38	* This file is part of the lwIP TCP/IP stack.
tax	0:66300c77c6e9	39	*
tax	0:66300c77c6e9	40	* Author: Adam Dunkels <adam@sics.se>
tax	0:66300c77c6e9	41	*
tax	0:66300c77c6e9	42	*/
tax	0:66300c77c6e9	43
tax	0:66300c77c6e9	44	#include "lwip/opt.h"
tax	0:66300c77c6e9	45
tax	0:66300c77c6e9	46	#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
tax	0:66300c77c6e9	47
tax	0:66300c77c6e9	48	#include "lwip/tcp_impl.h"
tax	0:66300c77c6e9	49	#include "lwip/def.h"
tax	0:66300c77c6e9	50	#include "lwip/ip_addr.h"
tax	0:66300c77c6e9	51	#include "lwip/netif.h"
tax	0:66300c77c6e9	52	#include "lwip/mem.h"
tax	0:66300c77c6e9	53	#include "lwip/memp.h"
tax	0:66300c77c6e9	54	#include "lwip/inet_chksum.h"
tax	0:66300c77c6e9	55	#include "lwip/stats.h"
tax	0:66300c77c6e9	56	#include "lwip/snmp.h"
tax	0:66300c77c6e9	57	#include "arch/perf.h"
tax	0:66300c77c6e9	58
tax	0:66300c77c6e9	59	/* These variables are global to all functions involved in the input
tax	0:66300c77c6e9	60	processing of TCP segments. They are set by the tcp_input()
tax	0:66300c77c6e9	61	function. */
tax	0:66300c77c6e9	62	static struct tcp_seg inseg;
tax	0:66300c77c6e9	63	static struct tcp_hdr *tcphdr;
tax	0:66300c77c6e9	64	static struct ip_hdr *iphdr;
tax	0:66300c77c6e9	65	static u32_t seqno, ackno;
tax	0:66300c77c6e9	66	static u8_t flags;
tax	0:66300c77c6e9	67	static u16_t tcplen;
tax	0:66300c77c6e9	68
tax	0:66300c77c6e9	69	static u8_t recv_flags;
tax	0:66300c77c6e9	70	static struct pbuf *recv_data;
tax	0:66300c77c6e9	71
tax	0:66300c77c6e9	72	struct tcp_pcb *tcp_input_pcb;
tax	0:66300c77c6e9	73
tax	0:66300c77c6e9	74	/* Forward declarations. */
tax	0:66300c77c6e9	75	static err_t tcp_process(struct tcp_pcb *pcb);
tax	0:66300c77c6e9	76	static void tcp_receive(struct tcp_pcb *pcb);
tax	0:66300c77c6e9	77	static void tcp_parseopt(struct tcp_pcb *pcb);
tax	0:66300c77c6e9	78
tax	0:66300c77c6e9	79	static err_t tcp_listen_input(struct tcp_pcb_listen *pcb);
tax	0:66300c77c6e9	80	static err_t tcp_timewait_input(struct tcp_pcb *pcb);
tax	0:66300c77c6e9	81
tax	0:66300c77c6e9	82	/**
tax	0:66300c77c6e9	83	* The initial input processing of TCP. It verifies the TCP header, demultiplexes
tax	0:66300c77c6e9	84	* the segment between the PCBs and passes it on to tcp_process(), which implements
tax	0:66300c77c6e9	85	* the TCP finite state machine. This function is called by the IP layer (in
tax	0:66300c77c6e9	86	* ip_input()).
tax	0:66300c77c6e9	87	*
tax	0:66300c77c6e9	88	* @param p received TCP segment to process (p->payload pointing to the IP header)
tax	0:66300c77c6e9	89	* @param inp network interface on which this segment was received
tax	0:66300c77c6e9	90	*/
tax	0:66300c77c6e9	91	void
tax	0:66300c77c6e9	92	tcp_input(struct pbuf p, struct netif inp)
tax	0:66300c77c6e9	93	{
tax	0:66300c77c6e9	94	struct tcp_pcb pcb, prev;
tax	0:66300c77c6e9	95	struct tcp_pcb_listen *lpcb;
tax	0:66300c77c6e9	96	#if SO_REUSE
tax	0:66300c77c6e9	97	struct tcp_pcb *lpcb_prev = NULL;
tax	0:66300c77c6e9	98	struct tcp_pcb_listen *lpcb_any = NULL;
tax	0:66300c77c6e9	99	#endif /* SO_REUSE */
tax	0:66300c77c6e9	100	u8_t hdrlen;
tax	0:66300c77c6e9	101	err_t err;
tax	0:66300c77c6e9	102
tax	0:66300c77c6e9	103	PERF_START;
tax	0:66300c77c6e9	104
tax	0:66300c77c6e9	105	TCP_STATS_INC(tcp.recv);
tax	0:66300c77c6e9	106	snmp_inc_tcpinsegs();
tax	0:66300c77c6e9	107
tax	0:66300c77c6e9	108	iphdr = (struct ip_hdr *)p->payload;
tax	0:66300c77c6e9	109	tcphdr = (struct tcp_hdr )((u8_t )p->payload + IPH_HL(iphdr) * 4);
tax	0:66300c77c6e9	110
tax	0:66300c77c6e9	111	#if TCP_INPUT_DEBUG
tax	0:66300c77c6e9	112	tcp_debug_print(tcphdr);
tax	0:66300c77c6e9	113	#endif
tax	0:66300c77c6e9	114
tax	0:66300c77c6e9	115	/* remove header from payload */
tax	0:66300c77c6e9	116	if (pbuf_header(p, -((s16_t)(IPH_HL(iphdr) * 4))) \|\| (p->tot_len < sizeof(struct tcp_hdr))) {
tax	0:66300c77c6e9	117	/* drop short packets */
tax	0:66300c77c6e9	118	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: short packet (%"U16_F" bytes) discarded\n", p->tot_len));
tax	0:66300c77c6e9	119	TCP_STATS_INC(tcp.lenerr);
tax	0:66300c77c6e9	120	TCP_STATS_INC(tcp.drop);
tax	0:66300c77c6e9	121	snmp_inc_tcpinerrs();
tax	0:66300c77c6e9	122	pbuf_free(p);
tax	0:66300c77c6e9	123	return;
tax	0:66300c77c6e9	124	}
tax	0:66300c77c6e9	125
tax	0:66300c77c6e9	126	/* Don't even process incoming broadcasts/multicasts. */
tax	0:66300c77c6e9	127	if (ip_addr_isbroadcast(&current_iphdr_dest, inp) \|\|
tax	0:66300c77c6e9	128	ip_addr_ismulticast(&current_iphdr_dest)) {
tax	0:66300c77c6e9	129	TCP_STATS_INC(tcp.proterr);
tax	0:66300c77c6e9	130	TCP_STATS_INC(tcp.drop);
tax	0:66300c77c6e9	131	snmp_inc_tcpinerrs();
tax	0:66300c77c6e9	132	pbuf_free(p);
tax	0:66300c77c6e9	133	return;
tax	0:66300c77c6e9	134	}
tax	0:66300c77c6e9	135
tax	0:66300c77c6e9	136	#if CHECKSUM_CHECK_TCP
tax	0:66300c77c6e9	137	/* Verify TCP checksum. */
tax	0:66300c77c6e9	138	if (inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(),
tax	0:66300c77c6e9	139	IP_PROTO_TCP, p->tot_len) != 0) {
tax	0:66300c77c6e9	140	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packet discarded due to failing checksum 0x%04"X16_F"\n",
tax	0:66300c77c6e9	141	inet_chksum_pseudo(p, ip_current_src_addr(), ip_current_dest_addr(),
tax	0:66300c77c6e9	142	IP_PROTO_TCP, p->tot_len)));
tax	0:66300c77c6e9	143	#if TCP_DEBUG
tax	0:66300c77c6e9	144	tcp_debug_print(tcphdr);
tax	0:66300c77c6e9	145	#endif /* TCP_DEBUG */
tax	0:66300c77c6e9	146	TCP_STATS_INC(tcp.chkerr);
tax	0:66300c77c6e9	147	TCP_STATS_INC(tcp.drop);
tax	0:66300c77c6e9	148	snmp_inc_tcpinerrs();
tax	0:66300c77c6e9	149	pbuf_free(p);
tax	0:66300c77c6e9	150	return;
tax	0:66300c77c6e9	151	}
tax	0:66300c77c6e9	152	#endif
tax	0:66300c77c6e9	153
tax	0:66300c77c6e9	154	/* Move the payload pointer in the pbuf so that it points to the
tax	0:66300c77c6e9	155	TCP data instead of the TCP header. */
tax	0:66300c77c6e9	156	hdrlen = TCPH_HDRLEN(tcphdr);
tax	0:66300c77c6e9	157	if(pbuf_header(p, -(hdrlen * 4))){
tax	0:66300c77c6e9	158	/* drop short packets */
tax	0:66300c77c6e9	159	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: short packet\n"));
tax	0:66300c77c6e9	160	TCP_STATS_INC(tcp.lenerr);
tax	0:66300c77c6e9	161	TCP_STATS_INC(tcp.drop);
tax	0:66300c77c6e9	162	snmp_inc_tcpinerrs();
tax	0:66300c77c6e9	163	pbuf_free(p);
tax	0:66300c77c6e9	164	return;
tax	0:66300c77c6e9	165	}
tax	0:66300c77c6e9	166
tax	0:66300c77c6e9	167	/* Convert fields in TCP header to host byte order. */
tax	0:66300c77c6e9	168	tcphdr->src = ntohs(tcphdr->src);
tax	0:66300c77c6e9	169	tcphdr->dest = ntohs(tcphdr->dest);
tax	0:66300c77c6e9	170	seqno = tcphdr->seqno = ntohl(tcphdr->seqno);
tax	0:66300c77c6e9	171	ackno = tcphdr->ackno = ntohl(tcphdr->ackno);
tax	0:66300c77c6e9	172	tcphdr->wnd = ntohs(tcphdr->wnd);
tax	0:66300c77c6e9	173
tax	0:66300c77c6e9	174	flags = TCPH_FLAGS(tcphdr);
tax	0:66300c77c6e9	175	tcplen = p->tot_len + ((flags & (TCP_FIN \| TCP_SYN)) ? 1 : 0);
tax	0:66300c77c6e9	176
tax	0:66300c77c6e9	177	/* Demultiplex an incoming segment. First, we check if it is destined
tax	0:66300c77c6e9	178	for an active connection. */
tax	0:66300c77c6e9	179	prev = NULL;
tax	0:66300c77c6e9	180
tax	0:66300c77c6e9	181
tax	0:66300c77c6e9	182	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
tax	0:66300c77c6e9	183	LWIP_ASSERT("tcp_input: active pcb->state != CLOSED", pcb->state != CLOSED);
tax	0:66300c77c6e9	184	LWIP_ASSERT("tcp_input: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
tax	0:66300c77c6e9	185	LWIP_ASSERT("tcp_input: active pcb->state != LISTEN", pcb->state != LISTEN);
tax	0:66300c77c6e9	186	if (pcb->remote_port == tcphdr->src &&
tax	0:66300c77c6e9	187	pcb->local_port == tcphdr->dest &&
tax	0:66300c77c6e9	188	ip_addr_cmp(&(pcb->remote_ip), &current_iphdr_src) &&
tax	0:66300c77c6e9	189	ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest)) {
tax	0:66300c77c6e9	190
tax	0:66300c77c6e9	191	/* Move this PCB to the front of the list so that subsequent
tax	0:66300c77c6e9	192	lookups will be faster (we exploit locality in TCP segment
tax	0:66300c77c6e9	193	arrivals). */
tax	0:66300c77c6e9	194	LWIP_ASSERT("tcp_input: pcb->next != pcb (before cache)", pcb->next != pcb);
tax	0:66300c77c6e9	195	if (prev != NULL) {
tax	0:66300c77c6e9	196	prev->next = pcb->next;
tax	0:66300c77c6e9	197	pcb->next = tcp_active_pcbs;
tax	0:66300c77c6e9	198	tcp_active_pcbs = pcb;
tax	0:66300c77c6e9	199	}
tax	0:66300c77c6e9	200	LWIP_ASSERT("tcp_input: pcb->next != pcb (after cache)", pcb->next != pcb);
tax	0:66300c77c6e9	201	break;
tax	0:66300c77c6e9	202	}
tax	0:66300c77c6e9	203	prev = pcb;
tax	0:66300c77c6e9	204	}
tax	0:66300c77c6e9	205
tax	0:66300c77c6e9	206	if (pcb == NULL) {
tax	0:66300c77c6e9	207	/* If it did not go to an active connection, we check the connections
tax	0:66300c77c6e9	208	in the TIME-WAIT state. */
tax	0:66300c77c6e9	209	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
tax	0:66300c77c6e9	210	LWIP_ASSERT("tcp_input: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
tax	0:66300c77c6e9	211	if (pcb->remote_port == tcphdr->src &&
tax	0:66300c77c6e9	212	pcb->local_port == tcphdr->dest &&
tax	0:66300c77c6e9	213	ip_addr_cmp(&(pcb->remote_ip), &current_iphdr_src) &&
tax	0:66300c77c6e9	214	ip_addr_cmp(&(pcb->local_ip), &current_iphdr_dest)) {
tax	0:66300c77c6e9	215	/* We don't really care enough to move this PCB to the front
tax	0:66300c77c6e9	216	of the list since we are not very likely to receive that
tax	0:66300c77c6e9	217	many segments for connections in TIME-WAIT. */
tax	0:66300c77c6e9	218	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packed for TIME_WAITing connection.\n"));
tax	0:66300c77c6e9	219	tcp_timewait_input(pcb);
tax	0:66300c77c6e9	220	pbuf_free(p);
tax	0:66300c77c6e9	221	return;
tax	0:66300c77c6e9	222	}
tax	0:66300c77c6e9	223	}
tax	0:66300c77c6e9	224
tax	0:66300c77c6e9	225	/* Finally, if we still did not get a match, we check all PCBs that
tax	0:66300c77c6e9	226	are LISTENing for incoming connections. */
tax	0:66300c77c6e9	227	prev = NULL;
tax	0:66300c77c6e9	228	for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
tax	0:66300c77c6e9	229	if (lpcb->local_port == tcphdr->dest) {
tax	0:66300c77c6e9	230	#if SO_REUSE
tax	0:66300c77c6e9	231	if (ip_addr_cmp(&(lpcb->local_ip), &current_iphdr_dest)) {
tax	0:66300c77c6e9	232	/* found an exact match */
tax	0:66300c77c6e9	233	break;
tax	0:66300c77c6e9	234	} else if(ip_addr_isany(&(lpcb->local_ip))) {
tax	0:66300c77c6e9	235	/* found an ANY-match */
tax	0:66300c77c6e9	236	lpcb_any = lpcb;
tax	0:66300c77c6e9	237	lpcb_prev = prev;
tax	0:66300c77c6e9	238	}
tax	0:66300c77c6e9	239	#else /* SO_REUSE */
tax	0:66300c77c6e9	240	if (ip_addr_cmp(&(lpcb->local_ip), &current_iphdr_dest) \|\|
tax	0:66300c77c6e9	241	ip_addr_isany(&(lpcb->local_ip))) {
tax	0:66300c77c6e9	242	/* found a match */
tax	0:66300c77c6e9	243	break;
tax	0:66300c77c6e9	244	}
tax	0:66300c77c6e9	245	#endif /* SO_REUSE */
tax	0:66300c77c6e9	246	}
tax	0:66300c77c6e9	247	prev = (struct tcp_pcb *)lpcb;
tax	0:66300c77c6e9	248	}
tax	0:66300c77c6e9	249	#if SO_REUSE
tax	0:66300c77c6e9	250	/* first try specific local IP */
tax	0:66300c77c6e9	251	if (lpcb == NULL) {
tax	0:66300c77c6e9	252	/* only pass to ANY if no specific local IP has been found */
tax	0:66300c77c6e9	253	lpcb = lpcb_any;
tax	0:66300c77c6e9	254	prev = lpcb_prev;
tax	0:66300c77c6e9	255	}
tax	0:66300c77c6e9	256	#endif /* SO_REUSE */
tax	0:66300c77c6e9	257	if (lpcb != NULL) {
tax	0:66300c77c6e9	258	/* Move this PCB to the front of the list so that subsequent
tax	0:66300c77c6e9	259	lookups will be faster (we exploit locality in TCP segment
tax	0:66300c77c6e9	260	arrivals). */
tax	0:66300c77c6e9	261	if (prev != NULL) {
tax	0:66300c77c6e9	262	((struct tcp_pcb_listen *)prev)->next = lpcb->next;
tax	0:66300c77c6e9	263	/* our successor is the remainder of the listening list */
tax	0:66300c77c6e9	264	lpcb->next = tcp_listen_pcbs.listen_pcbs;
tax	0:66300c77c6e9	265	/* put this listening pcb at the head of the listening list */
tax	0:66300c77c6e9	266	tcp_listen_pcbs.listen_pcbs = lpcb;
tax	0:66300c77c6e9	267	}
tax	0:66300c77c6e9	268
tax	0:66300c77c6e9	269	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packed for LISTENing connection.\n"));
tax	0:66300c77c6e9	270	tcp_listen_input(lpcb);
tax	0:66300c77c6e9	271	pbuf_free(p);
tax	0:66300c77c6e9	272	return;
tax	0:66300c77c6e9	273	}
tax	0:66300c77c6e9	274	}
tax	0:66300c77c6e9	275
tax	0:66300c77c6e9	276	#if TCP_INPUT_DEBUG
tax	0:66300c77c6e9	277	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("+-+-+-+-+-+-+-+-+-+-+-+-+-+- tcp_input: flags "));
tax	0:66300c77c6e9	278	tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
tax	0:66300c77c6e9	279	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("-+-+-+-+-+-+-+-+-+-+-+-+-+-+\n"));
tax	0:66300c77c6e9	280	#endif /* TCP_INPUT_DEBUG */
tax	0:66300c77c6e9	281
tax	0:66300c77c6e9	282
tax	0:66300c77c6e9	283	if (pcb != NULL) {
tax	0:66300c77c6e9	284	/* The incoming segment belongs to a connection. */
tax	0:66300c77c6e9	285	#if TCP_INPUT_DEBUG
tax	0:66300c77c6e9	286	#if TCP_DEBUG
tax	0:66300c77c6e9	287	tcp_debug_print_state(pcb->state);
tax	0:66300c77c6e9	288	#endif /* TCP_DEBUG */
tax	0:66300c77c6e9	289	#endif /* TCP_INPUT_DEBUG */
tax	0:66300c77c6e9	290
tax	0:66300c77c6e9	291	/* Set up a tcp_seg structure. */
tax	0:66300c77c6e9	292	inseg.next = NULL;
tax	0:66300c77c6e9	293	inseg.len = p->tot_len;
tax	0:66300c77c6e9	294	inseg.dataptr = p->payload;
tax	0:66300c77c6e9	295	inseg.p = p;
tax	0:66300c77c6e9	296	inseg.tcphdr = tcphdr;
tax	0:66300c77c6e9	297
tax	0:66300c77c6e9	298	recv_data = NULL;
tax	0:66300c77c6e9	299	recv_flags = 0;
tax	0:66300c77c6e9	300
tax	0:66300c77c6e9	301	/* If there is data which was previously "refused" by upper layer */
tax	0:66300c77c6e9	302	if (pcb->refused_data != NULL) {
tax	0:66300c77c6e9	303	/* Notify again application with data previously received. */
tax	0:66300c77c6e9	304	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: notify kept packet\n"));
tax	0:66300c77c6e9	305	TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
tax	0:66300c77c6e9	306	if (err == ERR_OK) {
tax	0:66300c77c6e9	307	pcb->refused_data = NULL;
tax	0:66300c77c6e9	308	} else {
tax	0:66300c77c6e9	309	/* if err == ERR_ABRT, 'pcb' is already deallocated */
tax	0:66300c77c6e9	310	/* drop incoming packets, because pcb is "full" */
tax	0:66300c77c6e9	311	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: drop incoming packets, because pcb is \"full\"\n"));
tax	0:66300c77c6e9	312	TCP_STATS_INC(tcp.drop);
tax	0:66300c77c6e9	313	snmp_inc_tcpinerrs();
tax	0:66300c77c6e9	314	pbuf_free(p);
tax	0:66300c77c6e9	315	return;
tax	0:66300c77c6e9	316	}
tax	0:66300c77c6e9	317	}
tax	0:66300c77c6e9	318	tcp_input_pcb = pcb;
tax	0:66300c77c6e9	319	err = tcp_process(pcb);
tax	0:66300c77c6e9	320	/* A return value of ERR_ABRT means that tcp_abort() was called
tax	0:66300c77c6e9	321	and that the pcb has been freed. If so, we don't do anything. */
tax	0:66300c77c6e9	322	if (err != ERR_ABRT) {
tax	0:66300c77c6e9	323	if (recv_flags & TF_RESET) {
tax	0:66300c77c6e9	324	/* TF_RESET means that the connection was reset by the other
tax	0:66300c77c6e9	325	end. We then call the error callback to inform the
tax	0:66300c77c6e9	326	application that the connection is dead before we
tax	0:66300c77c6e9	327	deallocate the PCB. */
tax	0:66300c77c6e9	328	TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_RST);
tax	0:66300c77c6e9	329	tcp_pcb_remove(&tcp_active_pcbs, pcb);
tax	0:66300c77c6e9	330	memp_free(MEMP_TCP_PCB, pcb);
tax	0:66300c77c6e9	331	} else if (recv_flags & TF_CLOSED) {
tax	0:66300c77c6e9	332	/* The connection has been closed and we will deallocate the
tax	0:66300c77c6e9	333	PCB. */
tax	0:66300c77c6e9	334	tcp_pcb_remove(&tcp_active_pcbs, pcb);
tax	0:66300c77c6e9	335	memp_free(MEMP_TCP_PCB, pcb);
tax	0:66300c77c6e9	336	} else {
tax	0:66300c77c6e9	337	err = ERR_OK;
tax	0:66300c77c6e9	338	/* If the application has registered a "sent" function to be
tax	0:66300c77c6e9	339	called when new send buffer space is available, we call it
tax	0:66300c77c6e9	340	now. */
tax	0:66300c77c6e9	341	if (pcb->acked > 0) {
tax	0:66300c77c6e9	342	TCP_EVENT_SENT(pcb, pcb->acked, err);
tax	0:66300c77c6e9	343	if (err == ERR_ABRT) {
tax	0:66300c77c6e9	344	goto aborted;
tax	0:66300c77c6e9	345	}
tax	0:66300c77c6e9	346	}
tax	0:66300c77c6e9	347
tax	0:66300c77c6e9	348	if (recv_data != NULL) {
tax	0:66300c77c6e9	349	if (pcb->flags & TF_RXCLOSED) {
tax	0:66300c77c6e9	350	/* received data although already closed -> abort (send RST) to
tax	0:66300c77c6e9	351	notify the remote host that not all data has been processed */
tax	0:66300c77c6e9	352	pbuf_free(recv_data);
tax	0:66300c77c6e9	353	tcp_abort(pcb);
tax	0:66300c77c6e9	354	goto aborted;
tax	0:66300c77c6e9	355	}
tax	0:66300c77c6e9	356	if (flags & TCP_PSH) {
tax	0:66300c77c6e9	357	recv_data->flags \|= PBUF_FLAG_PUSH;
tax	0:66300c77c6e9	358	}
tax	0:66300c77c6e9	359
tax	0:66300c77c6e9	360	/* Notify application that data has been received. */
tax	0:66300c77c6e9	361	TCP_EVENT_RECV(pcb, recv_data, ERR_OK, err);
tax	0:66300c77c6e9	362	if (err == ERR_ABRT) {
tax	0:66300c77c6e9	363	goto aborted;
tax	0:66300c77c6e9	364	}
tax	0:66300c77c6e9	365
tax	0:66300c77c6e9	366	/* If the upper layer can't receive this data, store it */
tax	0:66300c77c6e9	367	if (err != ERR_OK) {
tax	0:66300c77c6e9	368	pcb->refused_data = recv_data;
tax	0:66300c77c6e9	369	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: keep incoming packet, because pcb is \"full\"\n"));
tax	0:66300c77c6e9	370	}
tax	0:66300c77c6e9	371	}
tax	0:66300c77c6e9	372
tax	0:66300c77c6e9	373	/* If a FIN segment was received, we call the callback
tax	0:66300c77c6e9	374	function with a NULL buffer to indicate EOF. */
tax	0:66300c77c6e9	375	if (recv_flags & TF_GOT_FIN) {
tax	0:66300c77c6e9	376	/* correct rcv_wnd as the application won't call tcp_recved()
tax	0:66300c77c6e9	377	for the FIN's seqno */
tax	0:66300c77c6e9	378	if (pcb->rcv_wnd != TCP_WND) {
tax	0:66300c77c6e9	379	pcb->rcv_wnd++;
tax	0:66300c77c6e9	380	}
tax	0:66300c77c6e9	381	TCP_EVENT_CLOSED(pcb, err);
tax	0:66300c77c6e9	382	if (err == ERR_ABRT) {
tax	0:66300c77c6e9	383	goto aborted;
tax	0:66300c77c6e9	384	}
tax	0:66300c77c6e9	385	}
tax	0:66300c77c6e9	386
tax	0:66300c77c6e9	387	tcp_input_pcb = NULL;
tax	0:66300c77c6e9	388	/* Try to send something out. */
tax	0:66300c77c6e9	389	tcp_output(pcb);
tax	0:66300c77c6e9	390	#if TCP_INPUT_DEBUG
tax	0:66300c77c6e9	391	#if TCP_DEBUG
tax	0:66300c77c6e9	392	tcp_debug_print_state(pcb->state);
tax	0:66300c77c6e9	393	#endif /* TCP_DEBUG */
tax	0:66300c77c6e9	394	#endif /* TCP_INPUT_DEBUG */
tax	0:66300c77c6e9	395	}
tax	0:66300c77c6e9	396	}
tax	0:66300c77c6e9	397	/* Jump target if pcb has been aborted in a callback (by calling tcp_abort()).
tax	0:66300c77c6e9	398	Below this line, 'pcb' may not be dereferenced! */
tax	0:66300c77c6e9	399	aborted:
tax	0:66300c77c6e9	400	tcp_input_pcb = NULL;
tax	0:66300c77c6e9	401	recv_data = NULL;
tax	0:66300c77c6e9	402
tax	0:66300c77c6e9	403	/* give up our reference to inseg.p */
tax	0:66300c77c6e9	404	if (inseg.p != NULL)
tax	0:66300c77c6e9	405	{
tax	0:66300c77c6e9	406	pbuf_free(inseg.p);
tax	0:66300c77c6e9	407	inseg.p = NULL;
tax	0:66300c77c6e9	408	}
tax	0:66300c77c6e9	409	} else {
tax	0:66300c77c6e9	410
tax	0:66300c77c6e9	411	/* If no matching PCB was found, send a TCP RST (reset) to the
tax	0:66300c77c6e9	412	sender. */
tax	0:66300c77c6e9	413	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_input: no PCB match found, resetting.\n"));
tax	0:66300c77c6e9	414	if (!(TCPH_FLAGS(tcphdr) & TCP_RST)) {
tax	0:66300c77c6e9	415	TCP_STATS_INC(tcp.proterr);
tax	0:66300c77c6e9	416	TCP_STATS_INC(tcp.drop);
tax	0:66300c77c6e9	417	tcp_rst(ackno, seqno + tcplen,
tax	0:66300c77c6e9	418	ip_current_dest_addr(), ip_current_src_addr(),
tax	0:66300c77c6e9	419	tcphdr->dest, tcphdr->src);
tax	0:66300c77c6e9	420	}
tax	0:66300c77c6e9	421	pbuf_free(p);
tax	0:66300c77c6e9	422	}
tax	0:66300c77c6e9	423
tax	0:66300c77c6e9	424	LWIP_ASSERT("tcp_input: tcp_pcbs_sane()", tcp_pcbs_sane());
tax	0:66300c77c6e9	425	PERF_STOP("tcp_input");
tax	0:66300c77c6e9	426	}
tax	0:66300c77c6e9	427
tax	0:66300c77c6e9	428	/**
tax	0:66300c77c6e9	429	* Called by tcp_input() when a segment arrives for a listening
tax	0:66300c77c6e9	430	* connection (from tcp_input()).
tax	0:66300c77c6e9	431	*
tax	0:66300c77c6e9	432	* @param pcb the tcp_pcb_listen for which a segment arrived
tax	0:66300c77c6e9	433	* @return ERR_OK if the segment was processed
tax	0:66300c77c6e9	434	* another err_t on error
tax	0:66300c77c6e9	435	*
tax	0:66300c77c6e9	436	* @note the return value is not (yet?) used in tcp_input()
tax	0:66300c77c6e9	437	* @note the segment which arrived is saved in global variables, therefore only the pcb
tax	0:66300c77c6e9	438	* involved is passed as a parameter to this function
tax	0:66300c77c6e9	439	*/
tax	0:66300c77c6e9	440	static err_t
tax	0:66300c77c6e9	441	tcp_listen_input(struct tcp_pcb_listen *pcb)
tax	0:66300c77c6e9	442	{
tax	0:66300c77c6e9	443	struct tcp_pcb *npcb;
tax	0:66300c77c6e9	444	err_t rc;
tax	0:66300c77c6e9	445
tax	0:66300c77c6e9	446	/* In the LISTEN state, we check for incoming SYN segments,
tax	0:66300c77c6e9	447	creates a new PCB, and responds with a SYN\|ACK. */
tax	0:66300c77c6e9	448	if (flags & TCP_ACK) {
tax	0:66300c77c6e9	449	/* For incoming segments with the ACK flag set, respond with a
tax	0:66300c77c6e9	450	RST. */
tax	0:66300c77c6e9	451	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_listen_input: ACK in LISTEN, sending reset\n"));
tax	0:66300c77c6e9	452	tcp_rst(ackno + 1, seqno + tcplen,
tax	0:66300c77c6e9	453	ip_current_dest_addr(), ip_current_src_addr(),
tax	0:66300c77c6e9	454	tcphdr->dest, tcphdr->src);
tax	0:66300c77c6e9	455	} else if (flags & TCP_SYN) {
tax	0:66300c77c6e9	456	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection request %"U16_F" -> %"U16_F".\n", tcphdr->src, tcphdr->dest));
tax	0:66300c77c6e9	457	#if TCP_LISTEN_BACKLOG
tax	0:66300c77c6e9	458	if (pcb->accepts_pending >= pcb->backlog) {
tax	0:66300c77c6e9	459	LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: listen backlog exceeded for port %"U16_F"\n", tcphdr->dest));
tax	0:66300c77c6e9	460	return ERR_ABRT;
tax	0:66300c77c6e9	461	}
tax	0:66300c77c6e9	462	#endif /* TCP_LISTEN_BACKLOG */
tax	0:66300c77c6e9	463	npcb = tcp_alloc(pcb->prio);
tax	0:66300c77c6e9	464	/* If a new PCB could not be created (probably due to lack of memory),
tax	0:66300c77c6e9	465	we don't do anything, but rely on the sender will retransmit the
tax	0:66300c77c6e9	466	SYN at a time when we have more memory available. */
tax	0:66300c77c6e9	467	if (npcb == NULL) {
tax	0:66300c77c6e9	468	LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: could not allocate PCB\n"));
tax	0:66300c77c6e9	469	TCP_STATS_INC(tcp.memerr);
tax	0:66300c77c6e9	470	return ERR_MEM;
tax	0:66300c77c6e9	471	}
tax	0:66300c77c6e9	472	#if TCP_LISTEN_BACKLOG
tax	0:66300c77c6e9	473	pcb->accepts_pending++;
tax	0:66300c77c6e9	474	#endif /* TCP_LISTEN_BACKLOG */
tax	0:66300c77c6e9	475	/* Set up the new PCB. */
tax	0:66300c77c6e9	476	ip_addr_copy(npcb->local_ip, current_iphdr_dest);
tax	0:66300c77c6e9	477	npcb->local_port = pcb->local_port;
tax	0:66300c77c6e9	478	ip_addr_copy(npcb->remote_ip, current_iphdr_src);
tax	0:66300c77c6e9	479	npcb->remote_port = tcphdr->src;
tax	0:66300c77c6e9	480	npcb->state = SYN_RCVD;
tax	0:66300c77c6e9	481	npcb->rcv_nxt = seqno + 1;
tax	0:66300c77c6e9	482	npcb->rcv_ann_right_edge = npcb->rcv_nxt;
tax	0:66300c77c6e9	483	npcb->snd_wnd = tcphdr->wnd;
tax	0:66300c77c6e9	484	npcb->ssthresh = npcb->snd_wnd;
tax	0:66300c77c6e9	485	npcb->snd_wl1 = seqno - 1;/* initialise to seqno-1 to force window update */
tax	0:66300c77c6e9	486	npcb->callback_arg = pcb->callback_arg;
tax	0:66300c77c6e9	487	#if LWIP_CALLBACK_API
tax	0:66300c77c6e9	488	npcb->accept = pcb->accept;
tax	0:66300c77c6e9	489	#endif /* LWIP_CALLBACK_API */
tax	0:66300c77c6e9	490	/* inherit socket options */
tax	0:66300c77c6e9	491	npcb->so_options = pcb->so_options & SOF_INHERITED;
tax	0:66300c77c6e9	492	/* Register the new PCB so that we can begin receiving segments
tax	0:66300c77c6e9	493	for it. */
tax	0:66300c77c6e9	494	TCP_REG(&tcp_active_pcbs, npcb);
tax	0:66300c77c6e9	495
tax	0:66300c77c6e9	496	/* Parse any options in the SYN. */
tax	0:66300c77c6e9	497	tcp_parseopt(npcb);
tax	0:66300c77c6e9	498	#if TCP_CALCULATE_EFF_SEND_MSS
tax	0:66300c77c6e9	499	npcb->mss = tcp_eff_send_mss(npcb->mss, &(npcb->remote_ip));
tax	0:66300c77c6e9	500	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
tax	0:66300c77c6e9	501
tax	0:66300c77c6e9	502	snmp_inc_tcppassiveopens();
tax	0:66300c77c6e9	503
tax	0:66300c77c6e9	504	/* Send a SYN\|ACK together with the MSS option. */
tax	0:66300c77c6e9	505	rc = tcp_enqueue_flags(npcb, TCP_SYN \| TCP_ACK);
tax	0:66300c77c6e9	506	if (rc != ERR_OK) {
tax	0:66300c77c6e9	507	tcp_abandon(npcb, 0);
tax	0:66300c77c6e9	508	return rc;
tax	0:66300c77c6e9	509	}
tax	0:66300c77c6e9	510	return tcp_output(npcb);
tax	0:66300c77c6e9	511	}
tax	0:66300c77c6e9	512	return ERR_OK;
tax	0:66300c77c6e9	513	}
tax	0:66300c77c6e9	514
tax	0:66300c77c6e9	515	/**
tax	0:66300c77c6e9	516	* Called by tcp_input() when a segment arrives for a connection in
tax	0:66300c77c6e9	517	* TIME_WAIT.
tax	0:66300c77c6e9	518	*
tax	0:66300c77c6e9	519	* @param pcb the tcp_pcb for which a segment arrived
tax	0:66300c77c6e9	520	*
tax	0:66300c77c6e9	521	* @note the segment which arrived is saved in global variables, therefore only the pcb
tax	0:66300c77c6e9	522	* involved is passed as a parameter to this function
tax	0:66300c77c6e9	523	*/
tax	0:66300c77c6e9	524	static err_t
tax	0:66300c77c6e9	525	tcp_timewait_input(struct tcp_pcb *pcb)
tax	0:66300c77c6e9	526	{
tax	0:66300c77c6e9	527	/* RFC 1337: in TIME_WAIT, ignore RST and ACK FINs + any 'acceptable' segments */
tax	0:66300c77c6e9	528	/* RFC 793 3.9 Event Processing - Segment Arrives:
tax	0:66300c77c6e9	529	* - first check sequence number - we skip that one in TIME_WAIT (always
tax	0:66300c77c6e9	530	* acceptable since we only send ACKs)
tax	0:66300c77c6e9	531	* - second check the RST bit (... return) */
tax	0:66300c77c6e9	532	if (flags & TCP_RST) {
tax	0:66300c77c6e9	533	return ERR_OK;
tax	0:66300c77c6e9	534	}
tax	0:66300c77c6e9	535	/* - fourth, check the SYN bit, */
tax	0:66300c77c6e9	536	if (flags & TCP_SYN) {
tax	0:66300c77c6e9	537	/* If an incoming segment is not acceptable, an acknowledgment
tax	0:66300c77c6e9	538	should be sent in reply */
tax	0:66300c77c6e9	539	if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt+pcb->rcv_wnd)) {
tax	0:66300c77c6e9	540	/* If the SYN is in the window it is an error, send a reset */
tax	0:66300c77c6e9	541	tcp_rst(ackno, seqno + tcplen, ip_current_dest_addr(), ip_current_src_addr(),
tax	0:66300c77c6e9	542	tcphdr->dest, tcphdr->src);
tax	0:66300c77c6e9	543	return ERR_OK;
tax	0:66300c77c6e9	544	}
tax	0:66300c77c6e9	545	} else if (flags & TCP_FIN) {
tax	0:66300c77c6e9	546	/* - eighth, check the FIN bit: Remain in the TIME-WAIT state.
tax	0:66300c77c6e9	547	Restart the 2 MSL time-wait timeout.*/
tax	0:66300c77c6e9	548	pcb->tmr = tcp_ticks;
tax	0:66300c77c6e9	549	}
tax	0:66300c77c6e9	550
tax	0:66300c77c6e9	551	if ((tcplen > 0)) {
tax	0:66300c77c6e9	552	/* Acknowledge data, FIN or out-of-window SYN */
tax	0:66300c77c6e9	553	pcb->flags \|= TF_ACK_NOW;
tax	0:66300c77c6e9	554	return tcp_output(pcb);
tax	0:66300c77c6e9	555	}
tax	0:66300c77c6e9	556	return ERR_OK;
tax	0:66300c77c6e9	557	}
tax	0:66300c77c6e9	558
tax	0:66300c77c6e9	559	/**
tax	0:66300c77c6e9	560	* Implements the TCP state machine. Called by tcp_input. In some
tax	0:66300c77c6e9	561	* states tcp_receive() is called to receive data. The tcp_seg
tax	0:66300c77c6e9	562	* argument will be freed by the caller (tcp_input()) unless the
tax	0:66300c77c6e9	563	* recv_data pointer in the pcb is set.
tax	0:66300c77c6e9	564	*
tax	0:66300c77c6e9	565	* @param pcb the tcp_pcb for which a segment arrived
tax	0:66300c77c6e9	566	*
tax	0:66300c77c6e9	567	* @note the segment which arrived is saved in global variables, therefore only the pcb
tax	0:66300c77c6e9	568	* involved is passed as a parameter to this function
tax	0:66300c77c6e9	569	*/
tax	0:66300c77c6e9	570	static err_t
tax	0:66300c77c6e9	571	tcp_process(struct tcp_pcb *pcb)
tax	0:66300c77c6e9	572	{
tax	0:66300c77c6e9	573	struct tcp_seg *rseg;
tax	0:66300c77c6e9	574	u8_t acceptable = 0;
tax	0:66300c77c6e9	575	err_t err;
tax	0:66300c77c6e9	576
tax	0:66300c77c6e9	577	err = ERR_OK;
tax	0:66300c77c6e9	578
tax	0:66300c77c6e9	579	/* Process incoming RST segments. */
tax	0:66300c77c6e9	580	if (flags & TCP_RST) {
tax	0:66300c77c6e9	581	/* First, determine if the reset is acceptable. */
tax	0:66300c77c6e9	582	if (pcb->state == SYN_SENT) {
tax	0:66300c77c6e9	583	if (ackno == pcb->snd_nxt) {
tax	0:66300c77c6e9	584	acceptable = 1;
tax	0:66300c77c6e9	585	}
tax	0:66300c77c6e9	586	} else {
tax	0:66300c77c6e9	587	if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt,
tax	0:66300c77c6e9	588	pcb->rcv_nxt+pcb->rcv_wnd)) {
tax	0:66300c77c6e9	589	acceptable = 1;
tax	0:66300c77c6e9	590	}
tax	0:66300c77c6e9	591	}
tax	0:66300c77c6e9	592
tax	0:66300c77c6e9	593	if (acceptable) {
tax	0:66300c77c6e9	594	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_process: Connection RESET\n"));
tax	0:66300c77c6e9	595	LWIP_ASSERT("tcp_input: pcb->state != CLOSED", pcb->state != CLOSED);
tax	0:66300c77c6e9	596	recv_flags \|= TF_RESET;
tax	0:66300c77c6e9	597	pcb->flags &= ~TF_ACK_DELAY;
tax	0:66300c77c6e9	598	return ERR_RST;
tax	0:66300c77c6e9	599	} else {
tax	0:66300c77c6e9	600	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_process: unacceptable reset seqno %"U32_F" rcv_nxt %"U32_F"\n",
tax	0:66300c77c6e9	601	seqno, pcb->rcv_nxt));
tax	0:66300c77c6e9	602	LWIP_DEBUGF(TCP_DEBUG, ("tcp_process: unacceptable reset seqno %"U32_F" rcv_nxt %"U32_F"\n",
tax	0:66300c77c6e9	603	seqno, pcb->rcv_nxt));
tax	0:66300c77c6e9	604	return ERR_OK;
tax	0:66300c77c6e9	605	}
tax	0:66300c77c6e9	606	}
tax	0:66300c77c6e9	607
tax	0:66300c77c6e9	608	if ((flags & TCP_SYN) && (pcb->state != SYN_SENT && pcb->state != SYN_RCVD)) {
tax	0:66300c77c6e9	609	/* Cope with new connection attempt after remote end crashed */
tax	0:66300c77c6e9	610	tcp_ack_now(pcb);
tax	0:66300c77c6e9	611	return ERR_OK;
tax	0:66300c77c6e9	612	}
tax	0:66300c77c6e9	613
tax	0:66300c77c6e9	614	if ((pcb->flags & TF_RXCLOSED) == 0) {
tax	0:66300c77c6e9	615	/* Update the PCB (in)activity timer unless rx is closed (see tcp_shutdown) */
tax	0:66300c77c6e9	616	pcb->tmr = tcp_ticks;
tax	0:66300c77c6e9	617	}
tax	0:66300c77c6e9	618	pcb->keep_cnt_sent = 0;
tax	0:66300c77c6e9	619
tax	0:66300c77c6e9	620	tcp_parseopt(pcb);
tax	0:66300c77c6e9	621
tax	0:66300c77c6e9	622	/* Do different things depending on the TCP state. */
tax	0:66300c77c6e9	623	switch (pcb->state) {
tax	0:66300c77c6e9	624	case SYN_SENT:
tax	0:66300c77c6e9	625	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("SYN-SENT: ackno %"U32_F" pcb->snd_nxt %"U32_F" unacked %"U32_F"\n", ackno,
tax	0:66300c77c6e9	626	pcb->snd_nxt, ntohl(pcb->unacked->tcphdr->seqno)));
tax	0:66300c77c6e9	627	/* received SYN ACK with expected sequence number? */
tax	0:66300c77c6e9	628	if ((flags & TCP_ACK) && (flags & TCP_SYN)
tax	0:66300c77c6e9	629	&& ackno == ntohl(pcb->unacked->tcphdr->seqno) + 1) {
tax	0:66300c77c6e9	630	pcb->snd_buf++;
tax	0:66300c77c6e9	631	pcb->rcv_nxt = seqno + 1;
tax	0:66300c77c6e9	632	pcb->rcv_ann_right_edge = pcb->rcv_nxt;
tax	0:66300c77c6e9	633	pcb->lastack = ackno;
tax	0:66300c77c6e9	634	pcb->snd_wnd = tcphdr->wnd;
tax	0:66300c77c6e9	635	pcb->snd_wl1 = seqno - 1; /* initialise to seqno - 1 to force window update */
tax	0:66300c77c6e9	636	pcb->state = ESTABLISHED;
tax	0:66300c77c6e9	637
tax	0:66300c77c6e9	638	#if TCP_CALCULATE_EFF_SEND_MSS
tax	0:66300c77c6e9	639	pcb->mss = tcp_eff_send_mss(pcb->mss, &(pcb->remote_ip));
tax	0:66300c77c6e9	640	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
tax	0:66300c77c6e9	641
tax	0:66300c77c6e9	642	/* Set ssthresh again after changing pcb->mss (already set in tcp_connect
tax	0:66300c77c6e9	643	* but for the default value of pcb->mss) */
tax	0:66300c77c6e9	644	pcb->ssthresh = pcb->mss * 10;
tax	0:66300c77c6e9	645
tax	0:66300c77c6e9	646	pcb->cwnd = ((pcb->cwnd == 1) ? (pcb->mss * 2) : pcb->mss);
tax	0:66300c77c6e9	647	LWIP_ASSERT("pcb->snd_queuelen > 0", (pcb->snd_queuelen > 0));
tax	0:66300c77c6e9	648	--pcb->snd_queuelen;
tax	0:66300c77c6e9	649	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_process: SYN-SENT --queuelen %"U16_F"\n", (u16_t)pcb->snd_queuelen));
tax	0:66300c77c6e9	650	rseg = pcb->unacked;
tax	0:66300c77c6e9	651	pcb->unacked = rseg->next;
tax	0:66300c77c6e9	652
tax	0:66300c77c6e9	653	/* If there's nothing left to acknowledge, stop the retransmit
tax	0:66300c77c6e9	654	timer, otherwise reset it to start again */
tax	0:66300c77c6e9	655	if(pcb->unacked == NULL)
tax	0:66300c77c6e9	656	pcb->rtime = -1;
tax	0:66300c77c6e9	657	else {
tax	0:66300c77c6e9	658	pcb->rtime = 0;
tax	0:66300c77c6e9	659	pcb->nrtx = 0;
tax	0:66300c77c6e9	660	}
tax	0:66300c77c6e9	661
tax	0:66300c77c6e9	662	tcp_seg_free(rseg);
tax	0:66300c77c6e9	663
tax	0:66300c77c6e9	664	/* Call the user specified function to call when sucessfully
tax	0:66300c77c6e9	665	* connected. */
tax	0:66300c77c6e9	666	TCP_EVENT_CONNECTED(pcb, ERR_OK, err);
tax	0:66300c77c6e9	667	if (err == ERR_ABRT) {
tax	0:66300c77c6e9	668	return ERR_ABRT;
tax	0:66300c77c6e9	669	}
tax	0:66300c77c6e9	670	tcp_ack_now(pcb);
tax	0:66300c77c6e9	671	}
tax	0:66300c77c6e9	672	/* received ACK? possibly a half-open connection */
tax	0:66300c77c6e9	673	else if (flags & TCP_ACK) {
tax	0:66300c77c6e9	674	/* send a RST to bring the other side in a non-synchronized state. */
tax	0:66300c77c6e9	675	tcp_rst(ackno, seqno + tcplen, ip_current_dest_addr(), ip_current_src_addr(),
tax	0:66300c77c6e9	676	tcphdr->dest, tcphdr->src);
tax	0:66300c77c6e9	677	}
tax	0:66300c77c6e9	678	break;
tax	0:66300c77c6e9	679	case SYN_RCVD:
tax	0:66300c77c6e9	680	if (flags & TCP_ACK) {
tax	0:66300c77c6e9	681	/* expected ACK number? */
tax	0:66300c77c6e9	682	if (TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt)) {
tax	0:66300c77c6e9	683	u16_t old_cwnd;
tax	0:66300c77c6e9	684	pcb->state = ESTABLISHED;
tax	0:66300c77c6e9	685	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection established %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
tax	0:66300c77c6e9	686	#if LWIP_CALLBACK_API
tax	0:66300c77c6e9	687	LWIP_ASSERT("pcb->accept != NULL", pcb->accept != NULL);
tax	0:66300c77c6e9	688	#endif
tax	0:66300c77c6e9	689	/* Call the accept function. */
tax	0:66300c77c6e9	690	TCP_EVENT_ACCEPT(pcb, ERR_OK, err);
tax	0:66300c77c6e9	691	if (err != ERR_OK) {
tax	0:66300c77c6e9	692	/* If the accept function returns with an error, we abort
tax	0:66300c77c6e9	693	* the connection. */
tax	0:66300c77c6e9	694	/* Already aborted? */
tax	0:66300c77c6e9	695	if (err != ERR_ABRT) {
tax	0:66300c77c6e9	696	tcp_abort(pcb);
tax	0:66300c77c6e9	697	}
tax	0:66300c77c6e9	698	return ERR_ABRT;
tax	0:66300c77c6e9	699	}
tax	0:66300c77c6e9	700	old_cwnd = pcb->cwnd;
tax	0:66300c77c6e9	701	/* If there was any data contained within this ACK,
tax	0:66300c77c6e9	702	* we'd better pass it on to the application as well. */
tax	0:66300c77c6e9	703	tcp_receive(pcb);
tax	0:66300c77c6e9	704
tax	0:66300c77c6e9	705	/* Prevent ACK for SYN to generate a sent event */
tax	0:66300c77c6e9	706	if (pcb->acked != 0) {
tax	0:66300c77c6e9	707	pcb->acked--;
tax	0:66300c77c6e9	708	}
tax	0:66300c77c6e9	709
tax	0:66300c77c6e9	710	pcb->cwnd = ((old_cwnd == 1) ? (pcb->mss * 2) : pcb->mss);
tax	0:66300c77c6e9	711
tax	0:66300c77c6e9	712	if (recv_flags & TF_GOT_FIN) {
tax	0:66300c77c6e9	713	tcp_ack_now(pcb);
tax	0:66300c77c6e9	714	pcb->state = CLOSE_WAIT;
tax	0:66300c77c6e9	715	}
tax	0:66300c77c6e9	716	} else {
tax	0:66300c77c6e9	717	/* incorrect ACK number, send RST */
tax	0:66300c77c6e9	718	tcp_rst(ackno, seqno + tcplen, ip_current_dest_addr(), ip_current_src_addr(),
tax	0:66300c77c6e9	719	tcphdr->dest, tcphdr->src);
tax	0:66300c77c6e9	720	}
tax	0:66300c77c6e9	721	} else if ((flags & TCP_SYN) && (seqno == pcb->rcv_nxt - 1)) {
tax	0:66300c77c6e9	722	/* Looks like another copy of the SYN - retransmit our SYN-ACK */
tax	0:66300c77c6e9	723	tcp_rexmit(pcb);
tax	0:66300c77c6e9	724	}
tax	0:66300c77c6e9	725	break;
tax	0:66300c77c6e9	726	case CLOSE_WAIT:
tax	0:66300c77c6e9	727	/* FALLTHROUGH */
tax	0:66300c77c6e9	728	case ESTABLISHED:
tax	0:66300c77c6e9	729	tcp_receive(pcb);
tax	0:66300c77c6e9	730	if (recv_flags & TF_GOT_FIN) { /* passive close */
tax	0:66300c77c6e9	731	tcp_ack_now(pcb);
tax	0:66300c77c6e9	732	pcb->state = CLOSE_WAIT;
tax	0:66300c77c6e9	733	}
tax	0:66300c77c6e9	734	break;
tax	0:66300c77c6e9	735	case FIN_WAIT_1:
tax	0:66300c77c6e9	736	tcp_receive(pcb);
tax	0:66300c77c6e9	737	if (recv_flags & TF_GOT_FIN) {
tax	0:66300c77c6e9	738	if ((flags & TCP_ACK) && (ackno == pcb->snd_nxt)) {
tax	0:66300c77c6e9	739	LWIP_DEBUGF(TCP_DEBUG,
tax	0:66300c77c6e9	740	("TCP connection closed: FIN_WAIT_1 %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
tax	0:66300c77c6e9	741	tcp_ack_now(pcb);
tax	0:66300c77c6e9	742	tcp_pcb_purge(pcb);
tax	0:66300c77c6e9	743	TCP_RMV(&tcp_active_pcbs, pcb);
tax	0:66300c77c6e9	744	pcb->state = TIME_WAIT;
tax	0:66300c77c6e9	745	TCP_REG(&tcp_tw_pcbs, pcb);
tax	0:66300c77c6e9	746	} else {
tax	0:66300c77c6e9	747	tcp_ack_now(pcb);
tax	0:66300c77c6e9	748	pcb->state = CLOSING;
tax	0:66300c77c6e9	749	}
tax	0:66300c77c6e9	750	} else if ((flags & TCP_ACK) && (ackno == pcb->snd_nxt)) {
tax	0:66300c77c6e9	751	pcb->state = FIN_WAIT_2;
tax	0:66300c77c6e9	752	}
tax	0:66300c77c6e9	753	break;
tax	0:66300c77c6e9	754	case FIN_WAIT_2:
tax	0:66300c77c6e9	755	tcp_receive(pcb);
tax	0:66300c77c6e9	756	if (recv_flags & TF_GOT_FIN) {
tax	0:66300c77c6e9	757	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: FIN_WAIT_2 %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
tax	0:66300c77c6e9	758	tcp_ack_now(pcb);
tax	0:66300c77c6e9	759	tcp_pcb_purge(pcb);
tax	0:66300c77c6e9	760	TCP_RMV(&tcp_active_pcbs, pcb);
tax	0:66300c77c6e9	761	pcb->state = TIME_WAIT;
tax	0:66300c77c6e9	762	TCP_REG(&tcp_tw_pcbs, pcb);
tax	0:66300c77c6e9	763	}
tax	0:66300c77c6e9	764	break;
tax	0:66300c77c6e9	765	case CLOSING:
tax	0:66300c77c6e9	766	tcp_receive(pcb);
tax	0:66300c77c6e9	767	if (flags & TCP_ACK && ackno == pcb->snd_nxt) {
tax	0:66300c77c6e9	768	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: CLOSING %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
tax	0:66300c77c6e9	769	tcp_pcb_purge(pcb);
tax	0:66300c77c6e9	770	TCP_RMV(&tcp_active_pcbs, pcb);
tax	0:66300c77c6e9	771	pcb->state = TIME_WAIT;
tax	0:66300c77c6e9	772	TCP_REG(&tcp_tw_pcbs, pcb);
tax	0:66300c77c6e9	773	}
tax	0:66300c77c6e9	774	break;
tax	0:66300c77c6e9	775	case LAST_ACK:
tax	0:66300c77c6e9	776	tcp_receive(pcb);
tax	0:66300c77c6e9	777	if (flags & TCP_ACK && ackno == pcb->snd_nxt) {
tax	0:66300c77c6e9	778	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: LAST_ACK %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
tax	0:66300c77c6e9	779	/* bugfix #21699: don't set pcb->state to CLOSED here or we risk leaking segments */
tax	0:66300c77c6e9	780	recv_flags \|= TF_CLOSED;
tax	0:66300c77c6e9	781	}
tax	0:66300c77c6e9	782	break;
tax	0:66300c77c6e9	783	default:
tax	0:66300c77c6e9	784	break;
tax	0:66300c77c6e9	785	}
tax	0:66300c77c6e9	786	return ERR_OK;
tax	0:66300c77c6e9	787	}
tax	0:66300c77c6e9	788
tax	0:66300c77c6e9	789	#if TCP_QUEUE_OOSEQ
tax	0:66300c77c6e9	790	/**
tax	0:66300c77c6e9	791	* Insert segment into the list (segments covered with new one will be deleted)
tax	0:66300c77c6e9	792	*
tax	0:66300c77c6e9	793	* Called from tcp_receive()
tax	0:66300c77c6e9	794	*/
tax	0:66300c77c6e9	795	static void
tax	0:66300c77c6e9	796	tcp_oos_insert_segment(struct tcp_seg cseg, struct tcp_seg next)
tax	0:66300c77c6e9	797	{
tax	0:66300c77c6e9	798	struct tcp_seg *old_seg;
tax	0:66300c77c6e9	799
tax	0:66300c77c6e9	800	if (TCPH_FLAGS(cseg->tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	801	/* received segment overlaps all following segments */
tax	0:66300c77c6e9	802	tcp_segs_free(next);
tax	0:66300c77c6e9	803	next = NULL;
tax	0:66300c77c6e9	804	}
tax	0:66300c77c6e9	805	else {
tax	0:66300c77c6e9	806	/* delete some following segments
tax	0:66300c77c6e9	807	oos queue may have segments with FIN flag */
tax	0:66300c77c6e9	808	while (next &&
tax	0:66300c77c6e9	809	TCP_SEQ_GEQ((seqno + cseg->len),
tax	0:66300c77c6e9	810	(next->tcphdr->seqno + next->len))) {
tax	0:66300c77c6e9	811	/* cseg with FIN already processed */
tax	0:66300c77c6e9	812	if (TCPH_FLAGS(next->tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	813	TCPH_SET_FLAG(cseg->tcphdr, TCP_FIN);
tax	0:66300c77c6e9	814	}
tax	0:66300c77c6e9	815	old_seg = next;
tax	0:66300c77c6e9	816	next = next->next;
tax	0:66300c77c6e9	817	tcp_seg_free(old_seg);
tax	0:66300c77c6e9	818	}
tax	0:66300c77c6e9	819	if (next &&
tax	0:66300c77c6e9	820	TCP_SEQ_GT(seqno + cseg->len, next->tcphdr->seqno)) {
tax	0:66300c77c6e9	821	/* We need to trim the incoming segment. */
tax	0:66300c77c6e9	822	cseg->len = (u16_t)(next->tcphdr->seqno - seqno);
tax	0:66300c77c6e9	823	pbuf_realloc(cseg->p, cseg->len);
tax	0:66300c77c6e9	824	}
tax	0:66300c77c6e9	825	}
tax	0:66300c77c6e9	826	cseg->next = next;
tax	0:66300c77c6e9	827	}
tax	0:66300c77c6e9	828	#endif /* TCP_QUEUE_OOSEQ */
tax	0:66300c77c6e9	829
tax	0:66300c77c6e9	830	/**
tax	0:66300c77c6e9	831	* Called by tcp_process. Checks if the given segment is an ACK for outstanding
tax	0:66300c77c6e9	832	* data, and if so frees the memory of the buffered data. Next, is places the
tax	0:66300c77c6e9	833	* segment on any of the receive queues (pcb->recved or pcb->ooseq). If the segment
tax	0:66300c77c6e9	834	* is buffered, the pbuf is referenced by pbuf_ref so that it will not be freed until
tax	0:66300c77c6e9	835	* i it has been removed from the buffer.
tax	0:66300c77c6e9	836	*
tax	0:66300c77c6e9	837	* If the incoming segment constitutes an ACK for a segment that was used for RTT
tax	0:66300c77c6e9	838	* estimation, the RTT is estimated here as well.
tax	0:66300c77c6e9	839	*
tax	0:66300c77c6e9	840	* Called from tcp_process().
tax	0:66300c77c6e9	841	*/
tax	0:66300c77c6e9	842	static void
tax	0:66300c77c6e9	843	tcp_receive(struct tcp_pcb *pcb)
tax	0:66300c77c6e9	844	{
tax	0:66300c77c6e9	845	struct tcp_seg *next;
tax	0:66300c77c6e9	846	#if TCP_QUEUE_OOSEQ
tax	0:66300c77c6e9	847	struct tcp_seg prev, cseg;
tax	0:66300c77c6e9	848	#endif /* TCP_QUEUE_OOSEQ */
tax	0:66300c77c6e9	849	struct pbuf *p;
tax	0:66300c77c6e9	850	s32_t off;
tax	0:66300c77c6e9	851	s16_t m;
tax	0:66300c77c6e9	852	u32_t right_wnd_edge;
tax	0:66300c77c6e9	853	u16_t new_tot_len;
tax	0:66300c77c6e9	854	int found_dupack = 0;
tax	0:66300c77c6e9	855
tax	0:66300c77c6e9	856	if (flags & TCP_ACK) {
tax	0:66300c77c6e9	857	right_wnd_edge = pcb->snd_wnd + pcb->snd_wl2;
tax	0:66300c77c6e9	858
tax	0:66300c77c6e9	859	/* Update window. */
tax	0:66300c77c6e9	860	if (TCP_SEQ_LT(pcb->snd_wl1, seqno) \|\|
tax	0:66300c77c6e9	861	(pcb->snd_wl1 == seqno && TCP_SEQ_LT(pcb->snd_wl2, ackno)) \|\|
tax	0:66300c77c6e9	862	(pcb->snd_wl2 == ackno && tcphdr->wnd > pcb->snd_wnd)) {
tax	0:66300c77c6e9	863	pcb->snd_wnd = tcphdr->wnd;
tax	0:66300c77c6e9	864	pcb->snd_wl1 = seqno;
tax	0:66300c77c6e9	865	pcb->snd_wl2 = ackno;
tax	0:66300c77c6e9	866	if (pcb->snd_wnd > 0 && pcb->persist_backoff > 0) {
tax	0:66300c77c6e9	867	pcb->persist_backoff = 0;
tax	0:66300c77c6e9	868	}
tax	0:66300c77c6e9	869	LWIP_DEBUGF(TCP_WND_DEBUG, ("tcp_receive: window update %"U16_F"\n", pcb->snd_wnd));
tax	0:66300c77c6e9	870	#if TCP_WND_DEBUG
tax	0:66300c77c6e9	871	} else {
tax	0:66300c77c6e9	872	if (pcb->snd_wnd != tcphdr->wnd) {
tax	0:66300c77c6e9	873	LWIP_DEBUGF(TCP_WND_DEBUG,
tax	0:66300c77c6e9	874	("tcp_receive: no window update lastack %"U32_F" ackno %"
tax	0:66300c77c6e9	875	U32_F" wl1 %"U32_F" seqno %"U32_F" wl2 %"U32_F"\n",
tax	0:66300c77c6e9	876	pcb->lastack, ackno, pcb->snd_wl1, seqno, pcb->snd_wl2));
tax	0:66300c77c6e9	877	}
tax	0:66300c77c6e9	878	#endif /* TCP_WND_DEBUG */
tax	0:66300c77c6e9	879	}
tax	0:66300c77c6e9	880
tax	0:66300c77c6e9	881	/* (From Stevens TCP/IP Illustrated Vol II, p970.) Its only a
tax	0:66300c77c6e9	882	* duplicate ack if:
tax	0:66300c77c6e9	883	* 1) It doesn't ACK new data
tax	0:66300c77c6e9	884	* 2) length of received packet is zero (i.e. no payload)
tax	0:66300c77c6e9	885	* 3) the advertised window hasn't changed
tax	0:66300c77c6e9	886	* 4) There is outstanding unacknowledged data (retransmission timer running)
tax	0:66300c77c6e9	887	* 5) The ACK is == biggest ACK sequence number so far seen (snd_una)
tax	0:66300c77c6e9	888	*
tax	0:66300c77c6e9	889	* If it passes all five, should process as a dupack:
tax	0:66300c77c6e9	890	* a) dupacks < 3: do nothing
tax	0:66300c77c6e9	891	* b) dupacks == 3: fast retransmit
tax	0:66300c77c6e9	892	* c) dupacks > 3: increase cwnd
tax	0:66300c77c6e9	893	*
tax	0:66300c77c6e9	894	* If it only passes 1-3, should reset dupack counter (and add to
tax	0:66300c77c6e9	895	* stats, which we don't do in lwIP)
tax	0:66300c77c6e9	896	*
tax	0:66300c77c6e9	897	* If it only passes 1, should reset dupack counter
tax	0:66300c77c6e9	898	*
tax	0:66300c77c6e9	899	*/
tax	0:66300c77c6e9	900
tax	0:66300c77c6e9	901	/* Clause 1 */
tax	0:66300c77c6e9	902	if (TCP_SEQ_LEQ(ackno, pcb->lastack)) {
tax	0:66300c77c6e9	903	pcb->acked = 0;
tax	0:66300c77c6e9	904	/* Clause 2 */
tax	0:66300c77c6e9	905	if (tcplen == 0) {
tax	0:66300c77c6e9	906	/* Clause 3 */
tax	0:66300c77c6e9	907	if (pcb->snd_wl2 + pcb->snd_wnd == right_wnd_edge){
tax	0:66300c77c6e9	908	/* Clause 4 */
tax	0:66300c77c6e9	909	if (pcb->rtime >= 0) {
tax	0:66300c77c6e9	910	/* Clause 5 */
tax	0:66300c77c6e9	911	if (pcb->lastack == ackno) {
tax	0:66300c77c6e9	912	found_dupack = 1;
tax	0:66300c77c6e9	913	if (pcb->dupacks + 1 > pcb->dupacks)
tax	0:66300c77c6e9	914	++pcb->dupacks;
tax	0:66300c77c6e9	915	if (pcb->dupacks > 3) {
tax	0:66300c77c6e9	916	/* Inflate the congestion window, but not if it means that
tax	0:66300c77c6e9	917	the value overflows. */
tax	0:66300c77c6e9	918	if ((u16_t)(pcb->cwnd + pcb->mss) > pcb->cwnd) {
tax	0:66300c77c6e9	919	pcb->cwnd += pcb->mss;
tax	0:66300c77c6e9	920	}
tax	0:66300c77c6e9	921	} else if (pcb->dupacks == 3) {
tax	0:66300c77c6e9	922	/* Do fast retransmit */
tax	0:66300c77c6e9	923	tcp_rexmit_fast(pcb);
tax	0:66300c77c6e9	924	}
tax	0:66300c77c6e9	925	}
tax	0:66300c77c6e9	926	}
tax	0:66300c77c6e9	927	}
tax	0:66300c77c6e9	928	}
tax	0:66300c77c6e9	929	/* If Clause (1) or more is true, but not a duplicate ack, reset
tax	0:66300c77c6e9	930	* count of consecutive duplicate acks */
tax	0:66300c77c6e9	931	if (!found_dupack) {
tax	0:66300c77c6e9	932	pcb->dupacks = 0;
tax	0:66300c77c6e9	933	}
tax	0:66300c77c6e9	934	} else if (TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt)){
tax	0:66300c77c6e9	935	/* We come here when the ACK acknowledges new data. */
tax	0:66300c77c6e9	936
tax	0:66300c77c6e9	937	/* Reset the "IN Fast Retransmit" flag, since we are no longer
tax	0:66300c77c6e9	938	in fast retransmit. Also reset the congestion window to the
tax	0:66300c77c6e9	939	slow start threshold. */
tax	0:66300c77c6e9	940	if (pcb->flags & TF_INFR) {
tax	0:66300c77c6e9	941	pcb->flags &= ~TF_INFR;
tax	0:66300c77c6e9	942	pcb->cwnd = pcb->ssthresh;
tax	0:66300c77c6e9	943	}
tax	0:66300c77c6e9	944
tax	0:66300c77c6e9	945	/* Reset the number of retransmissions. */
tax	0:66300c77c6e9	946	pcb->nrtx = 0;
tax	0:66300c77c6e9	947
tax	0:66300c77c6e9	948	/* Reset the retransmission time-out. */
tax	0:66300c77c6e9	949	pcb->rto = (pcb->sa >> 3) + pcb->sv;
tax	0:66300c77c6e9	950
tax	0:66300c77c6e9	951	/* Update the send buffer space. Diff between the two can never exceed 64K? */
tax	0:66300c77c6e9	952	pcb->acked = (u16_t)(ackno - pcb->lastack);
tax	0:66300c77c6e9	953
tax	0:66300c77c6e9	954	pcb->snd_buf += pcb->acked;
tax	0:66300c77c6e9	955
tax	0:66300c77c6e9	956	/* Reset the fast retransmit variables. */
tax	0:66300c77c6e9	957	pcb->dupacks = 0;
tax	0:66300c77c6e9	958	pcb->lastack = ackno;
tax	0:66300c77c6e9	959
tax	0:66300c77c6e9	960	/* Update the congestion control variables (cwnd and
tax	0:66300c77c6e9	961	ssthresh). */
tax	0:66300c77c6e9	962	if (pcb->state >= ESTABLISHED) {
tax	0:66300c77c6e9	963	if (pcb->cwnd < pcb->ssthresh) {
tax	0:66300c77c6e9	964	if ((u16_t)(pcb->cwnd + pcb->mss) > pcb->cwnd) {
tax	0:66300c77c6e9	965	pcb->cwnd += pcb->mss;
tax	0:66300c77c6e9	966	}
tax	0:66300c77c6e9	967	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_receive: slow start cwnd %"U16_F"\n", pcb->cwnd));
tax	0:66300c77c6e9	968	} else {
tax	0:66300c77c6e9	969	u16_t new_cwnd = (pcb->cwnd + pcb->mss * pcb->mss / pcb->cwnd);
tax	0:66300c77c6e9	970	if (new_cwnd > pcb->cwnd) {
tax	0:66300c77c6e9	971	pcb->cwnd = new_cwnd;
tax	0:66300c77c6e9	972	}
tax	0:66300c77c6e9	973	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_receive: congestion avoidance cwnd %"U16_F"\n", pcb->cwnd));
tax	0:66300c77c6e9	974	}
tax	0:66300c77c6e9	975	}
tax	0:66300c77c6e9	976	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: ACK for %"U32_F", unacked->seqno %"U32_F":%"U32_F"\n",
tax	0:66300c77c6e9	977	ackno,
tax	0:66300c77c6e9	978	pcb->unacked != NULL?
tax	0:66300c77c6e9	979	ntohl(pcb->unacked->tcphdr->seqno): 0,
tax	0:66300c77c6e9	980	pcb->unacked != NULL?
tax	0:66300c77c6e9	981	ntohl(pcb->unacked->tcphdr->seqno) + TCP_TCPLEN(pcb->unacked): 0));
tax	0:66300c77c6e9	982
tax	0:66300c77c6e9	983	/* Remove segment from the unacknowledged list if the incoming
tax	0:66300c77c6e9	984	ACK acknowlegdes them. */
tax	0:66300c77c6e9	985	while (pcb->unacked != NULL &&
tax	0:66300c77c6e9	986	TCP_SEQ_LEQ(ntohl(pcb->unacked->tcphdr->seqno) +
tax	0:66300c77c6e9	987	TCP_TCPLEN(pcb->unacked), ackno)) {
tax	0:66300c77c6e9	988	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %"U32_F":%"U32_F" from pcb->unacked\n",
tax	0:66300c77c6e9	989	ntohl(pcb->unacked->tcphdr->seqno),
tax	0:66300c77c6e9	990	ntohl(pcb->unacked->tcphdr->seqno) +
tax	0:66300c77c6e9	991	TCP_TCPLEN(pcb->unacked)));
tax	0:66300c77c6e9	992
tax	0:66300c77c6e9	993	next = pcb->unacked;
tax	0:66300c77c6e9	994	pcb->unacked = pcb->unacked->next;
tax	0:66300c77c6e9	995
tax	0:66300c77c6e9	996	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_receive: queuelen %"U16_F" ... ", (u16_t)pcb->snd_queuelen));
tax	0:66300c77c6e9	997	LWIP_ASSERT("pcb->snd_queuelen >= pbuf_clen(next->p)", (pcb->snd_queuelen >= pbuf_clen(next->p)));
tax	0:66300c77c6e9	998	/* Prevent ACK for FIN to generate a sent event */
tax	0:66300c77c6e9	999	if ((pcb->acked != 0) && ((TCPH_FLAGS(next->tcphdr) & TCP_FIN) != 0)) {
tax	0:66300c77c6e9	1000	pcb->acked--;
tax	0:66300c77c6e9	1001	}
tax	0:66300c77c6e9	1002
tax	0:66300c77c6e9	1003	pcb->snd_queuelen -= pbuf_clen(next->p);
tax	0:66300c77c6e9	1004	tcp_seg_free(next);
tax	0:66300c77c6e9	1005
tax	0:66300c77c6e9	1006	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("%"U16_F" (after freeing unacked)\n", (u16_t)pcb->snd_queuelen));
tax	0:66300c77c6e9	1007	if (pcb->snd_queuelen != 0) {
tax	0:66300c77c6e9	1008	LWIP_ASSERT("tcp_receive: valid queue length", pcb->unacked != NULL \|\|
tax	0:66300c77c6e9	1009	pcb->unsent != NULL);
tax	0:66300c77c6e9	1010	}
tax	0:66300c77c6e9	1011	}
tax	0:66300c77c6e9	1012
tax	0:66300c77c6e9	1013	/* If there's nothing left to acknowledge, stop the retransmit
tax	0:66300c77c6e9	1014	timer, otherwise reset it to start again */
tax	0:66300c77c6e9	1015	if(pcb->unacked == NULL)
tax	0:66300c77c6e9	1016	pcb->rtime = -1;
tax	0:66300c77c6e9	1017	else
tax	0:66300c77c6e9	1018	pcb->rtime = 0;
tax	0:66300c77c6e9	1019
tax	0:66300c77c6e9	1020	pcb->polltmr = 0;
tax	0:66300c77c6e9	1021	} else {
tax	0:66300c77c6e9	1022	/* Fix bug bug #21582: out of sequence ACK, didn't really ack anything */
tax	0:66300c77c6e9	1023	pcb->acked = 0;
tax	0:66300c77c6e9	1024	}
tax	0:66300c77c6e9	1025
tax	0:66300c77c6e9	1026	/* We go through the ->unsent list to see if any of the segments
tax	0:66300c77c6e9	1027	on the list are acknowledged by the ACK. This may seem
tax	0:66300c77c6e9	1028	strange since an "unsent" segment shouldn't be acked. The
tax	0:66300c77c6e9	1029	rationale is that lwIP puts all outstanding segments on the
tax	0:66300c77c6e9	1030	->unsent list after a retransmission, so these segments may
tax	0:66300c77c6e9	1031	in fact have been sent once. */
tax	0:66300c77c6e9	1032	while (pcb->unsent != NULL &&
tax	0:66300c77c6e9	1033	TCP_SEQ_BETWEEN(ackno, ntohl(pcb->unsent->tcphdr->seqno) +
tax	0:66300c77c6e9	1034	TCP_TCPLEN(pcb->unsent), pcb->snd_nxt)) {
tax	0:66300c77c6e9	1035	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %"U32_F":%"U32_F" from pcb->unsent\n",
tax	0:66300c77c6e9	1036	ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) +
tax	0:66300c77c6e9	1037	TCP_TCPLEN(pcb->unsent)));
tax	0:66300c77c6e9	1038
tax	0:66300c77c6e9	1039	next = pcb->unsent;
tax	0:66300c77c6e9	1040	pcb->unsent = pcb->unsent->next;
tax	0:66300c77c6e9	1041	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_receive: queuelen %"U16_F" ... ", (u16_t)pcb->snd_queuelen));
tax	0:66300c77c6e9	1042	LWIP_ASSERT("pcb->snd_queuelen >= pbuf_clen(next->p)", (pcb->snd_queuelen >= pbuf_clen(next->p)));
tax	0:66300c77c6e9	1043	/* Prevent ACK for FIN to generate a sent event */
tax	0:66300c77c6e9	1044	if ((pcb->acked != 0) && ((TCPH_FLAGS(next->tcphdr) & TCP_FIN) != 0)) {
tax	0:66300c77c6e9	1045	pcb->acked--;
tax	0:66300c77c6e9	1046	}
tax	0:66300c77c6e9	1047	pcb->snd_queuelen -= pbuf_clen(next->p);
tax	0:66300c77c6e9	1048	tcp_seg_free(next);
tax	0:66300c77c6e9	1049	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("%"U16_F" (after freeing unsent)\n", (u16_t)pcb->snd_queuelen));
tax	0:66300c77c6e9	1050	if (pcb->snd_queuelen != 0) {
tax	0:66300c77c6e9	1051	LWIP_ASSERT("tcp_receive: valid queue length",
tax	0:66300c77c6e9	1052	pcb->unacked != NULL \|\| pcb->unsent != NULL);
tax	0:66300c77c6e9	1053	}
tax	0:66300c77c6e9	1054	}
tax	0:66300c77c6e9	1055	/* End of ACK for new data processing. */
tax	0:66300c77c6e9	1056
tax	0:66300c77c6e9	1057	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: pcb->rttest %"U32_F" rtseq %"U32_F" ackno %"U32_F"\n",
tax	0:66300c77c6e9	1058	pcb->rttest, pcb->rtseq, ackno));
tax	0:66300c77c6e9	1059
tax	0:66300c77c6e9	1060	/* RTT estimation calculations. This is done by checking if the
tax	0:66300c77c6e9	1061	incoming segment acknowledges the segment we use to take a
tax	0:66300c77c6e9	1062	round-trip time measurement. */
tax	0:66300c77c6e9	1063	if (pcb->rttest && TCP_SEQ_LT(pcb->rtseq, ackno)) {
tax	0:66300c77c6e9	1064	/* diff between this shouldn't exceed 32K since this are tcp timer ticks
tax	0:66300c77c6e9	1065	and a round-trip shouldn't be that long... */
tax	0:66300c77c6e9	1066	m = (s16_t)(tcp_ticks - pcb->rttest);
tax	0:66300c77c6e9	1067
tax	0:66300c77c6e9	1068	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: experienced rtt %"U16_F" ticks (%"U16_F" msec).\n",
tax	0:66300c77c6e9	1069	m, m * TCP_SLOW_INTERVAL));
tax	0:66300c77c6e9	1070
tax	0:66300c77c6e9	1071	/* This is taken directly from VJs original code in his paper */
tax	0:66300c77c6e9	1072	m = m - (pcb->sa >> 3);
tax	0:66300c77c6e9	1073	pcb->sa += m;
tax	0:66300c77c6e9	1074	if (m < 0) {
tax	0:66300c77c6e9	1075	m = -m;
tax	0:66300c77c6e9	1076	}
tax	0:66300c77c6e9	1077	m = m - (pcb->sv >> 2);
tax	0:66300c77c6e9	1078	pcb->sv += m;
tax	0:66300c77c6e9	1079	pcb->rto = (pcb->sa >> 3) + pcb->sv;
tax	0:66300c77c6e9	1080
tax	0:66300c77c6e9	1081	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: RTO %"U16_F" (%"U16_F" milliseconds)\n",
tax	0:66300c77c6e9	1082	pcb->rto, pcb->rto * TCP_SLOW_INTERVAL));
tax	0:66300c77c6e9	1083
tax	0:66300c77c6e9	1084	pcb->rttest = 0;
tax	0:66300c77c6e9	1085	}
tax	0:66300c77c6e9	1086	}
tax	0:66300c77c6e9	1087
tax	0:66300c77c6e9	1088	/* If the incoming segment contains data, we must process it
tax	0:66300c77c6e9	1089	further. */
tax	0:66300c77c6e9	1090	if (tcplen > 0) {
tax	0:66300c77c6e9	1091	/* This code basically does three things:
tax	0:66300c77c6e9	1092
tax	0:66300c77c6e9	1093	+) If the incoming segment contains data that is the next
tax	0:66300c77c6e9	1094	in-sequence data, this data is passed to the application. This
tax	0:66300c77c6e9	1095	might involve trimming the first edge of the data. The rcv_nxt
tax	0:66300c77c6e9	1096	variable and the advertised window are adjusted.
tax	0:66300c77c6e9	1097
tax	0:66300c77c6e9	1098	+) If the incoming segment has data that is above the next
tax	0:66300c77c6e9	1099	sequence number expected (->rcv_nxt), the segment is placed on
tax	0:66300c77c6e9	1100	the ->ooseq queue. This is done by finding the appropriate
tax	0:66300c77c6e9	1101	place in the ->ooseq queue (which is ordered by sequence
tax	0:66300c77c6e9	1102	number) and trim the segment in both ends if needed. An
tax	0:66300c77c6e9	1103	immediate ACK is sent to indicate that we received an
tax	0:66300c77c6e9	1104	out-of-sequence segment.
tax	0:66300c77c6e9	1105
tax	0:66300c77c6e9	1106	+) Finally, we check if the first segment on the ->ooseq queue
tax	0:66300c77c6e9	1107	now is in sequence (i.e., if rcv_nxt >= ooseq->seqno). If
tax	0:66300c77c6e9	1108	rcv_nxt > ooseq->seqno, we must trim the first edge of the
tax	0:66300c77c6e9	1109	segment on ->ooseq before we adjust rcv_nxt. The data in the
tax	0:66300c77c6e9	1110	segments that are now on sequence are chained onto the
tax	0:66300c77c6e9	1111	incoming segment so that we only need to call the application
tax	0:66300c77c6e9	1112	once.
tax	0:66300c77c6e9	1113	*/
tax	0:66300c77c6e9	1114
tax	0:66300c77c6e9	1115	/* First, we check if we must trim the first edge. We have to do
tax	0:66300c77c6e9	1116	this if the sequence number of the incoming segment is less
tax	0:66300c77c6e9	1117	than rcv_nxt, and the sequence number plus the length of the
tax	0:66300c77c6e9	1118	segment is larger than rcv_nxt. */
tax	0:66300c77c6e9	1119	/* if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
tax	0:66300c77c6e9	1120	if (TCP_SEQ_LT(pcb->rcv_nxt, seqno + tcplen)) {*/
tax	0:66300c77c6e9	1121	if (TCP_SEQ_BETWEEN(pcb->rcv_nxt, seqno + 1, seqno + tcplen - 1)){
tax	0:66300c77c6e9	1122	/* Trimming the first edge is done by pushing the payload
tax	0:66300c77c6e9	1123	pointer in the pbuf downwards. This is somewhat tricky since
tax	0:66300c77c6e9	1124	we do not want to discard the full contents of the pbuf up to
tax	0:66300c77c6e9	1125	the new starting point of the data since we have to keep the
tax	0:66300c77c6e9	1126	TCP header which is present in the first pbuf in the chain.
tax	0:66300c77c6e9	1127
tax	0:66300c77c6e9	1128	What is done is really quite a nasty hack: the first pbuf in
tax	0:66300c77c6e9	1129	the pbuf chain is pointed to by inseg.p. Since we need to be
tax	0:66300c77c6e9	1130	able to deallocate the whole pbuf, we cannot change this
tax	0:66300c77c6e9	1131	inseg.p pointer to point to any of the later pbufs in the
tax	0:66300c77c6e9	1132	chain. Instead, we point the ->payload pointer in the first
tax	0:66300c77c6e9	1133	pbuf to data in one of the later pbufs. We also set the
tax	0:66300c77c6e9	1134	inseg.data pointer to point to the right place. This way, the
tax	0:66300c77c6e9	1135	->p pointer will still point to the first pbuf, but the
tax	0:66300c77c6e9	1136	->p->payload pointer will point to data in another pbuf.
tax	0:66300c77c6e9	1137
tax	0:66300c77c6e9	1138	After we are done with adjusting the pbuf pointers we must
tax	0:66300c77c6e9	1139	adjust the ->data pointer in the seg and the segment
tax	0:66300c77c6e9	1140	length.*/
tax	0:66300c77c6e9	1141
tax	0:66300c77c6e9	1142	off = pcb->rcv_nxt - seqno;
tax	0:66300c77c6e9	1143	p = inseg.p;
tax	0:66300c77c6e9	1144	LWIP_ASSERT("inseg.p != NULL", inseg.p);
tax	0:66300c77c6e9	1145	LWIP_ASSERT("insane offset!", (off < 0x7fff));
tax	0:66300c77c6e9	1146	if (inseg.p->len < off) {
tax	0:66300c77c6e9	1147	LWIP_ASSERT("pbuf too short!", (((s32_t)inseg.p->tot_len) >= off));
tax	0:66300c77c6e9	1148	new_tot_len = (u16_t)(inseg.p->tot_len - off);
tax	0:66300c77c6e9	1149	while (p->len < off) {
tax	0:66300c77c6e9	1150	off -= p->len;
tax	0:66300c77c6e9	1151	/* KJM following line changed (with addition of new_tot_len var)
tax	0:66300c77c6e9	1152	to fix bug #9076
tax	0:66300c77c6e9	1153	inseg.p->tot_len -= p->len; */
tax	0:66300c77c6e9	1154	p->tot_len = new_tot_len;
tax	0:66300c77c6e9	1155	p->len = 0;
tax	0:66300c77c6e9	1156	p = p->next;
tax	0:66300c77c6e9	1157	}
tax	0:66300c77c6e9	1158	if(pbuf_header(p, (s16_t)-off)) {
tax	0:66300c77c6e9	1159	/* Do we need to cope with this failing? Assert for now */
tax	0:66300c77c6e9	1160	LWIP_ASSERT("pbuf_header failed", 0);
tax	0:66300c77c6e9	1161	}
tax	0:66300c77c6e9	1162	} else {
tax	0:66300c77c6e9	1163	if(pbuf_header(inseg.p, (s16_t)-off)) {
tax	0:66300c77c6e9	1164	/* Do we need to cope with this failing? Assert for now */
tax	0:66300c77c6e9	1165	LWIP_ASSERT("pbuf_header failed", 0);
tax	0:66300c77c6e9	1166	}
tax	0:66300c77c6e9	1167	}
tax	0:66300c77c6e9	1168	/* KJM following line changed to use p->payload rather than inseg->p->payload
tax	0:66300c77c6e9	1169	to fix bug #9076 */
tax	0:66300c77c6e9	1170	inseg.dataptr = p->payload;
tax	0:66300c77c6e9	1171	inseg.len -= (u16_t)(pcb->rcv_nxt - seqno);
tax	0:66300c77c6e9	1172	inseg.tcphdr->seqno = seqno = pcb->rcv_nxt;
tax	0:66300c77c6e9	1173	}
tax	0:66300c77c6e9	1174	else {
tax	0:66300c77c6e9	1175	if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
tax	0:66300c77c6e9	1176	/* the whole segment is < rcv_nxt */
tax	0:66300c77c6e9	1177	/* must be a duplicate of a packet that has already been correctly handled */
tax	0:66300c77c6e9	1178
tax	0:66300c77c6e9	1179	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: duplicate seqno %"U32_F"\n", seqno));
tax	0:66300c77c6e9	1180	tcp_ack_now(pcb);
tax	0:66300c77c6e9	1181	}
tax	0:66300c77c6e9	1182	}
tax	0:66300c77c6e9	1183
tax	0:66300c77c6e9	1184	/* The sequence number must be within the window (above rcv_nxt
tax	0:66300c77c6e9	1185	and below rcv_nxt + rcv_wnd) in order to be further
tax	0:66300c77c6e9	1186	processed. */
tax	0:66300c77c6e9	1187	if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt,
tax	0:66300c77c6e9	1188	pcb->rcv_nxt + pcb->rcv_wnd - 1)){
tax	0:66300c77c6e9	1189	if (pcb->rcv_nxt == seqno) {
tax	0:66300c77c6e9	1190	/* The incoming segment is the next in sequence. We check if
tax	0:66300c77c6e9	1191	we have to trim the end of the segment and update rcv_nxt
tax	0:66300c77c6e9	1192	and pass the data to the application. */
tax	0:66300c77c6e9	1193	tcplen = TCP_TCPLEN(&inseg);
tax	0:66300c77c6e9	1194
tax	0:66300c77c6e9	1195	if (tcplen > pcb->rcv_wnd) {
tax	0:66300c77c6e9	1196	LWIP_DEBUGF(TCP_INPUT_DEBUG,
tax	0:66300c77c6e9	1197	("tcp_receive: other end overran receive window"
tax	0:66300c77c6e9	1198	"seqno %"U32_F" len %"U16_F" right edge %"U32_F"\n",
tax	0:66300c77c6e9	1199	seqno, tcplen, pcb->rcv_nxt + pcb->rcv_wnd));
tax	0:66300c77c6e9	1200	if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	1201	/* Must remove the FIN from the header as we're trimming
tax	0:66300c77c6e9	1202	* that byte of sequence-space from the packet */
tax	0:66300c77c6e9	1203	TCPH_FLAGS_SET(inseg.tcphdr, TCPH_FLAGS(inseg.tcphdr) &~ TCP_FIN);
tax	0:66300c77c6e9	1204	}
tax	0:66300c77c6e9	1205	/* Adjust length of segment to fit in the window. */
tax	0:66300c77c6e9	1206	inseg.len = pcb->rcv_wnd;
tax	0:66300c77c6e9	1207	if (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) {
tax	0:66300c77c6e9	1208	inseg.len -= 1;
tax	0:66300c77c6e9	1209	}
tax	0:66300c77c6e9	1210	pbuf_realloc(inseg.p, inseg.len);
tax	0:66300c77c6e9	1211	tcplen = TCP_TCPLEN(&inseg);
tax	0:66300c77c6e9	1212	LWIP_ASSERT("tcp_receive: segment not trimmed correctly to rcv_wnd\n",
tax	0:66300c77c6e9	1213	(seqno + tcplen) == (pcb->rcv_nxt + pcb->rcv_wnd));
tax	0:66300c77c6e9	1214	}
tax	0:66300c77c6e9	1215	#if TCP_QUEUE_OOSEQ
tax	0:66300c77c6e9	1216	/* Received in-sequence data, adjust ooseq data if:
tax	0:66300c77c6e9	1217	- FIN has been received or
tax	0:66300c77c6e9	1218	- inseq overlaps with ooseq */
tax	0:66300c77c6e9	1219	if (pcb->ooseq != NULL) {
tax	0:66300c77c6e9	1220	if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	1221	LWIP_DEBUGF(TCP_INPUT_DEBUG,
tax	0:66300c77c6e9	1222	("tcp_receive: received in-order FIN, binning ooseq queue\n"));
tax	0:66300c77c6e9	1223	/* Received in-order FIN means anything that was received
tax	0:66300c77c6e9	1224	* out of order must now have been received in-order, so
tax	0:66300c77c6e9	1225	* bin the ooseq queue */
tax	0:66300c77c6e9	1226	while (pcb->ooseq != NULL) {
tax	0:66300c77c6e9	1227	struct tcp_seg *old_ooseq = pcb->ooseq;
tax	0:66300c77c6e9	1228	pcb->ooseq = pcb->ooseq->next;
tax	0:66300c77c6e9	1229	tcp_seg_free(old_ooseq);
tax	0:66300c77c6e9	1230	}
tax	0:66300c77c6e9	1231	}
tax	0:66300c77c6e9	1232	else {
tax	0:66300c77c6e9	1233	next = pcb->ooseq;
tax	0:66300c77c6e9	1234	/* Remove all segments on ooseq that are covered by inseg already.
tax	0:66300c77c6e9	1235	* FIN is copied from ooseq to inseg if present. */
tax	0:66300c77c6e9	1236	while (next &&
tax	0:66300c77c6e9	1237	TCP_SEQ_GEQ(seqno + tcplen,
tax	0:66300c77c6e9	1238	next->tcphdr->seqno + next->len)) {
tax	0:66300c77c6e9	1239	/* inseg cannot have FIN here (already processed above) */
tax	0:66300c77c6e9	1240	if (TCPH_FLAGS(next->tcphdr) & TCP_FIN &&
tax	0:66300c77c6e9	1241	(TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) == 0) {
tax	0:66300c77c6e9	1242	TCPH_SET_FLAG(inseg.tcphdr, TCP_FIN);
tax	0:66300c77c6e9	1243	tcplen = TCP_TCPLEN(&inseg);
tax	0:66300c77c6e9	1244	}
tax	0:66300c77c6e9	1245	prev = next;
tax	0:66300c77c6e9	1246	next = next->next;
tax	0:66300c77c6e9	1247	tcp_seg_free(prev);
tax	0:66300c77c6e9	1248	}
tax	0:66300c77c6e9	1249	/* Now trim right side of inseg if it overlaps with the first
tax	0:66300c77c6e9	1250	* segment on ooseq */
tax	0:66300c77c6e9	1251	if (next &&
tax	0:66300c77c6e9	1252	TCP_SEQ_GT(seqno + tcplen,
tax	0:66300c77c6e9	1253	next->tcphdr->seqno)) {
tax	0:66300c77c6e9	1254	/* inseg cannot have FIN here (already processed above) */
tax	0:66300c77c6e9	1255	inseg.len = (u16_t)(next->tcphdr->seqno - seqno);
tax	0:66300c77c6e9	1256	if (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) {
tax	0:66300c77c6e9	1257	inseg.len -= 1;
tax	0:66300c77c6e9	1258	}
tax	0:66300c77c6e9	1259	pbuf_realloc(inseg.p, inseg.len);
tax	0:66300c77c6e9	1260	tcplen = TCP_TCPLEN(&inseg);
tax	0:66300c77c6e9	1261	LWIP_ASSERT("tcp_receive: segment not trimmed correctly to ooseq queue\n",
tax	0:66300c77c6e9	1262	(seqno + tcplen) == next->tcphdr->seqno);
tax	0:66300c77c6e9	1263	}
tax	0:66300c77c6e9	1264	pcb->ooseq = next;
tax	0:66300c77c6e9	1265	}
tax	0:66300c77c6e9	1266	}
tax	0:66300c77c6e9	1267	#endif /* TCP_QUEUE_OOSEQ */
tax	0:66300c77c6e9	1268
tax	0:66300c77c6e9	1269	pcb->rcv_nxt = seqno + tcplen;
tax	0:66300c77c6e9	1270
tax	0:66300c77c6e9	1271	/* Update the receiver's (our) window. */
tax	0:66300c77c6e9	1272	LWIP_ASSERT("tcp_receive: tcplen > rcv_wnd\n", pcb->rcv_wnd >= tcplen);
tax	0:66300c77c6e9	1273	pcb->rcv_wnd -= tcplen;
tax	0:66300c77c6e9	1274
tax	0:66300c77c6e9	1275	tcp_update_rcv_ann_wnd(pcb);
tax	0:66300c77c6e9	1276
tax	0:66300c77c6e9	1277	/* If there is data in the segment, we make preparations to
tax	0:66300c77c6e9	1278	pass this up to the application. The ->recv_data variable
tax	0:66300c77c6e9	1279	is used for holding the pbuf that goes to the
tax	0:66300c77c6e9	1280	application. The code for reassembling out-of-sequence data
tax	0:66300c77c6e9	1281	chains its data on this pbuf as well.
tax	0:66300c77c6e9	1282
tax	0:66300c77c6e9	1283	If the segment was a FIN, we set the TF_GOT_FIN flag that will
tax	0:66300c77c6e9	1284	be used to indicate to the application that the remote side has
tax	0:66300c77c6e9	1285	closed its end of the connection. */
tax	0:66300c77c6e9	1286	if (inseg.p->tot_len > 0) {
tax	0:66300c77c6e9	1287	recv_data = inseg.p;
tax	0:66300c77c6e9	1288	/* Since this pbuf now is the responsibility of the
tax	0:66300c77c6e9	1289	application, we delete our reference to it so that we won't
tax	0:66300c77c6e9	1290	(mistakingly) deallocate it. */
tax	0:66300c77c6e9	1291	inseg.p = NULL;
tax	0:66300c77c6e9	1292	}
tax	0:66300c77c6e9	1293	if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	1294	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: received FIN.\n"));
tax	0:66300c77c6e9	1295	recv_flags \|= TF_GOT_FIN;
tax	0:66300c77c6e9	1296	}
tax	0:66300c77c6e9	1297
tax	0:66300c77c6e9	1298	#if TCP_QUEUE_OOSEQ
tax	0:66300c77c6e9	1299	/* We now check if we have segments on the ->ooseq queue that
tax	0:66300c77c6e9	1300	are now in sequence. */
tax	0:66300c77c6e9	1301	while (pcb->ooseq != NULL &&
tax	0:66300c77c6e9	1302	pcb->ooseq->tcphdr->seqno == pcb->rcv_nxt) {
tax	0:66300c77c6e9	1303
tax	0:66300c77c6e9	1304	cseg = pcb->ooseq;
tax	0:66300c77c6e9	1305	seqno = pcb->ooseq->tcphdr->seqno;
tax	0:66300c77c6e9	1306
tax	0:66300c77c6e9	1307	pcb->rcv_nxt += TCP_TCPLEN(cseg);
tax	0:66300c77c6e9	1308	LWIP_ASSERT("tcp_receive: ooseq tcplen > rcv_wnd\n",
tax	0:66300c77c6e9	1309	pcb->rcv_wnd >= TCP_TCPLEN(cseg));
tax	0:66300c77c6e9	1310	pcb->rcv_wnd -= TCP_TCPLEN(cseg);
tax	0:66300c77c6e9	1311
tax	0:66300c77c6e9	1312	tcp_update_rcv_ann_wnd(pcb);
tax	0:66300c77c6e9	1313
tax	0:66300c77c6e9	1314	if (cseg->p->tot_len > 0) {
tax	0:66300c77c6e9	1315	/* Chain this pbuf onto the pbuf that we will pass to
tax	0:66300c77c6e9	1316	the application. */
tax	0:66300c77c6e9	1317	if (recv_data) {
tax	0:66300c77c6e9	1318	pbuf_cat(recv_data, cseg->p);
tax	0:66300c77c6e9	1319	} else {
tax	0:66300c77c6e9	1320	recv_data = cseg->p;
tax	0:66300c77c6e9	1321	}
tax	0:66300c77c6e9	1322	cseg->p = NULL;
tax	0:66300c77c6e9	1323	}
tax	0:66300c77c6e9	1324	if (TCPH_FLAGS(cseg->tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	1325	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: dequeued FIN.\n"));
tax	0:66300c77c6e9	1326	recv_flags \|= TF_GOT_FIN;
tax	0:66300c77c6e9	1327	if (pcb->state == ESTABLISHED) { /* force passive close or we can move to active close */
tax	0:66300c77c6e9	1328	pcb->state = CLOSE_WAIT;
tax	0:66300c77c6e9	1329	}
tax	0:66300c77c6e9	1330	}
tax	0:66300c77c6e9	1331
tax	0:66300c77c6e9	1332	pcb->ooseq = cseg->next;
tax	0:66300c77c6e9	1333	tcp_seg_free(cseg);
tax	0:66300c77c6e9	1334	}
tax	0:66300c77c6e9	1335	#endif /* TCP_QUEUE_OOSEQ */
tax	0:66300c77c6e9	1336
tax	0:66300c77c6e9	1337
tax	0:66300c77c6e9	1338	/* Acknowledge the segment(s). */
tax	0:66300c77c6e9	1339	tcp_ack(pcb);
tax	0:66300c77c6e9	1340
tax	0:66300c77c6e9	1341	} else {
tax	0:66300c77c6e9	1342	/* We get here if the incoming segment is out-of-sequence. */
tax	0:66300c77c6e9	1343	tcp_send_empty_ack(pcb);
tax	0:66300c77c6e9	1344	#if TCP_QUEUE_OOSEQ
tax	0:66300c77c6e9	1345	/* We queue the segment on the ->ooseq queue. */
tax	0:66300c77c6e9	1346	if (pcb->ooseq == NULL) {
tax	0:66300c77c6e9	1347	pcb->ooseq = tcp_seg_copy(&inseg);
tax	0:66300c77c6e9	1348	} else {
tax	0:66300c77c6e9	1349	/* If the queue is not empty, we walk through the queue and
tax	0:66300c77c6e9	1350	try to find a place where the sequence number of the
tax	0:66300c77c6e9	1351	incoming segment is between the sequence numbers of the
tax	0:66300c77c6e9	1352	previous and the next segment on the ->ooseq queue. That is
tax	0:66300c77c6e9	1353	the place where we put the incoming segment. If needed, we
tax	0:66300c77c6e9	1354	trim the second edges of the previous and the incoming
tax	0:66300c77c6e9	1355	segment so that it will fit into the sequence.
tax	0:66300c77c6e9	1356
tax	0:66300c77c6e9	1357	If the incoming segment has the same sequence number as a
tax	0:66300c77c6e9	1358	segment on the ->ooseq queue, we discard the segment that
tax	0:66300c77c6e9	1359	contains less data. */
tax	0:66300c77c6e9	1360
tax	0:66300c77c6e9	1361	prev = NULL;
tax	0:66300c77c6e9	1362	for(next = pcb->ooseq; next != NULL; next = next->next) {
tax	0:66300c77c6e9	1363	if (seqno == next->tcphdr->seqno) {
tax	0:66300c77c6e9	1364	/* The sequence number of the incoming segment is the
tax	0:66300c77c6e9	1365	same as the sequence number of the segment on
tax	0:66300c77c6e9	1366	->ooseq. We check the lengths to see which one to
tax	0:66300c77c6e9	1367	discard. */
tax	0:66300c77c6e9	1368	if (inseg.len > next->len) {
tax	0:66300c77c6e9	1369	/* The incoming segment is larger than the old
tax	0:66300c77c6e9	1370	segment. We replace some segments with the new
tax	0:66300c77c6e9	1371	one. */
tax	0:66300c77c6e9	1372	cseg = tcp_seg_copy(&inseg);
tax	0:66300c77c6e9	1373	if (cseg != NULL) {
tax	0:66300c77c6e9	1374	if (prev != NULL) {
tax	0:66300c77c6e9	1375	prev->next = cseg;
tax	0:66300c77c6e9	1376	} else {
tax	0:66300c77c6e9	1377	pcb->ooseq = cseg;
tax	0:66300c77c6e9	1378	}
tax	0:66300c77c6e9	1379	tcp_oos_insert_segment(cseg, next);
tax	0:66300c77c6e9	1380	}
tax	0:66300c77c6e9	1381	break;
tax	0:66300c77c6e9	1382	} else {
tax	0:66300c77c6e9	1383	/* Either the lenghts are the same or the incoming
tax	0:66300c77c6e9	1384	segment was smaller than the old one; in either
tax	0:66300c77c6e9	1385	case, we ditch the incoming segment. */
tax	0:66300c77c6e9	1386	break;
tax	0:66300c77c6e9	1387	}
tax	0:66300c77c6e9	1388	} else {
tax	0:66300c77c6e9	1389	if (prev == NULL) {
tax	0:66300c77c6e9	1390	if (TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {
tax	0:66300c77c6e9	1391	/* The sequence number of the incoming segment is lower
tax	0:66300c77c6e9	1392	than the sequence number of the first segment on the
tax	0:66300c77c6e9	1393	queue. We put the incoming segment first on the
tax	0:66300c77c6e9	1394	queue. */
tax	0:66300c77c6e9	1395	cseg = tcp_seg_copy(&inseg);
tax	0:66300c77c6e9	1396	if (cseg != NULL) {
tax	0:66300c77c6e9	1397	pcb->ooseq = cseg;
tax	0:66300c77c6e9	1398	tcp_oos_insert_segment(cseg, next);
tax	0:66300c77c6e9	1399	}
tax	0:66300c77c6e9	1400	break;
tax	0:66300c77c6e9	1401	}
tax	0:66300c77c6e9	1402	} else {
tax	0:66300c77c6e9	1403	/*if (TCP_SEQ_LT(prev->tcphdr->seqno, seqno) &&
tax	0:66300c77c6e9	1404	TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {*/
tax	0:66300c77c6e9	1405	if (TCP_SEQ_BETWEEN(seqno, prev->tcphdr->seqno+1, next->tcphdr->seqno-1)) {
tax	0:66300c77c6e9	1406	/* The sequence number of the incoming segment is in
tax	0:66300c77c6e9	1407	between the sequence numbers of the previous and
tax	0:66300c77c6e9	1408	the next segment on ->ooseq. We trim trim the previous
tax	0:66300c77c6e9	1409	segment, delete next segments that included in received segment
tax	0:66300c77c6e9	1410	and trim received, if needed. */
tax	0:66300c77c6e9	1411	cseg = tcp_seg_copy(&inseg);
tax	0:66300c77c6e9	1412	if (cseg != NULL) {
tax	0:66300c77c6e9	1413	if (TCP_SEQ_GT(prev->tcphdr->seqno + prev->len, seqno)) {
tax	0:66300c77c6e9	1414	/* We need to trim the prev segment. */
tax	0:66300c77c6e9	1415	prev->len = (u16_t)(seqno - prev->tcphdr->seqno);
tax	0:66300c77c6e9	1416	pbuf_realloc(prev->p, prev->len);
tax	0:66300c77c6e9	1417	}
tax	0:66300c77c6e9	1418	prev->next = cseg;
tax	0:66300c77c6e9	1419	tcp_oos_insert_segment(cseg, next);
tax	0:66300c77c6e9	1420	}
tax	0:66300c77c6e9	1421	break;
tax	0:66300c77c6e9	1422	}
tax	0:66300c77c6e9	1423	}
tax	0:66300c77c6e9	1424	/* If the "next" segment is the last segment on the
tax	0:66300c77c6e9	1425	ooseq queue, we add the incoming segment to the end
tax	0:66300c77c6e9	1426	of the list. */
tax	0:66300c77c6e9	1427	if (next->next == NULL &&
tax	0:66300c77c6e9	1428	TCP_SEQ_GT(seqno, next->tcphdr->seqno)) {
tax	0:66300c77c6e9	1429	if (TCPH_FLAGS(next->tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	1430	/* segment "next" already contains all data */
tax	0:66300c77c6e9	1431	break;
tax	0:66300c77c6e9	1432	}
tax	0:66300c77c6e9	1433	next->next = tcp_seg_copy(&inseg);
tax	0:66300c77c6e9	1434	if (next->next != NULL) {
tax	0:66300c77c6e9	1435	if (TCP_SEQ_GT(next->tcphdr->seqno + next->len, seqno)) {
tax	0:66300c77c6e9	1436	/* We need to trim the last segment. */
tax	0:66300c77c6e9	1437	next->len = (u16_t)(seqno - next->tcphdr->seqno);
tax	0:66300c77c6e9	1438	pbuf_realloc(next->p, next->len);
tax	0:66300c77c6e9	1439	}
tax	0:66300c77c6e9	1440	/* check if the remote side overruns our receive window */
tax	0:66300c77c6e9	1441	if ((u32_t)tcplen + seqno > pcb->rcv_nxt + (u32_t)pcb->rcv_wnd) {
tax	0:66300c77c6e9	1442	LWIP_DEBUGF(TCP_INPUT_DEBUG,
tax	0:66300c77c6e9	1443	("tcp_receive: other end overran receive window"
tax	0:66300c77c6e9	1444	"seqno %"U32_F" len %"U16_F" right edge %"U32_F"\n",
tax	0:66300c77c6e9	1445	seqno, tcplen, pcb->rcv_nxt + pcb->rcv_wnd));
tax	0:66300c77c6e9	1446	if (TCPH_FLAGS(next->next->tcphdr) & TCP_FIN) {
tax	0:66300c77c6e9	1447	/* Must remove the FIN from the header as we're trimming
tax	0:66300c77c6e9	1448	* that byte of sequence-space from the packet */
tax	0:66300c77c6e9	1449	TCPH_FLAGS_SET(next->next->tcphdr, TCPH_FLAGS(next->next->tcphdr) &~ TCP_FIN);
tax	0:66300c77c6e9	1450	}
tax	0:66300c77c6e9	1451	/* Adjust length of segment to fit in the window. */
tax	0:66300c77c6e9	1452	next->next->len = pcb->rcv_nxt + pcb->rcv_wnd - seqno;
tax	0:66300c77c6e9	1453	pbuf_realloc(next->next->p, next->next->len);
tax	0:66300c77c6e9	1454	tcplen = TCP_TCPLEN(next->next);
tax	0:66300c77c6e9	1455	LWIP_ASSERT("tcp_receive: segment not trimmed correctly to rcv_wnd\n",
tax	0:66300c77c6e9	1456	(seqno + tcplen) == (pcb->rcv_nxt + pcb->rcv_wnd));
tax	0:66300c77c6e9	1457	}
tax	0:66300c77c6e9	1458	}
tax	0:66300c77c6e9	1459	break;
tax	0:66300c77c6e9	1460	}
tax	0:66300c77c6e9	1461	}
tax	0:66300c77c6e9	1462	prev = next;
tax	0:66300c77c6e9	1463	}
tax	0:66300c77c6e9	1464	}
tax	0:66300c77c6e9	1465	#endif /* TCP_QUEUE_OOSEQ */
tax	0:66300c77c6e9	1466
tax	0:66300c77c6e9	1467	}
tax	0:66300c77c6e9	1468	} else {
tax	0:66300c77c6e9	1469	/* The incoming segment is not withing the window. */
tax	0:66300c77c6e9	1470	tcp_send_empty_ack(pcb);
tax	0:66300c77c6e9	1471	}
tax	0:66300c77c6e9	1472	} else {
tax	0:66300c77c6e9	1473	/* Segments with length 0 is taken care of here. Segments that
tax	0:66300c77c6e9	1474	fall out of the window are ACKed. */
tax	0:66300c77c6e9	1475	/*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) \|\|
tax	0:66300c77c6e9	1476	TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {*/
tax	0:66300c77c6e9	1477	if(!TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt + pcb->rcv_wnd-1)){
tax	0:66300c77c6e9	1478	tcp_ack_now(pcb);
tax	0:66300c77c6e9	1479	}
tax	0:66300c77c6e9	1480	}
tax	0:66300c77c6e9	1481	}
tax	0:66300c77c6e9	1482
tax	0:66300c77c6e9	1483	/**
tax	0:66300c77c6e9	1484	* Parses the options contained in the incoming segment.
tax	0:66300c77c6e9	1485	*
tax	0:66300c77c6e9	1486	* Called from tcp_listen_input() and tcp_process().
tax	0:66300c77c6e9	1487	* Currently, only the MSS option is supported!
tax	0:66300c77c6e9	1488	*
tax	0:66300c77c6e9	1489	* @param pcb the tcp_pcb for which a segment arrived
tax	0:66300c77c6e9	1490	*/
tax	0:66300c77c6e9	1491	static void
tax	0:66300c77c6e9	1492	tcp_parseopt(struct tcp_pcb *pcb)
tax	0:66300c77c6e9	1493	{
tax	0:66300c77c6e9	1494	u16_t c, max_c;
tax	0:66300c77c6e9	1495	u16_t mss;
tax	0:66300c77c6e9	1496	u8_t *opts, opt;
tax	0:66300c77c6e9	1497	#if LWIP_TCP_TIMESTAMPS
tax	0:66300c77c6e9	1498	u32_t tsval;
tax	0:66300c77c6e9	1499	#endif
tax	0:66300c77c6e9	1500
tax	0:66300c77c6e9	1501	opts = (u8_t *)tcphdr + TCP_HLEN;
tax	0:66300c77c6e9	1502
tax	0:66300c77c6e9	1503	/* Parse the TCP MSS option, if present. */
tax	0:66300c77c6e9	1504	if(TCPH_HDRLEN(tcphdr) > 0x5) {
tax	0:66300c77c6e9	1505	max_c = (TCPH_HDRLEN(tcphdr) - 5) << 2;
tax	0:66300c77c6e9	1506	for (c = 0; c < max_c; ) {
tax	0:66300c77c6e9	1507	opt = opts[c];
tax	0:66300c77c6e9	1508	switch (opt) {
tax	0:66300c77c6e9	1509	case 0x00:
tax	0:66300c77c6e9	1510	/* End of options. */
tax	0:66300c77c6e9	1511	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: EOL\n"));
tax	0:66300c77c6e9	1512	return;
tax	0:66300c77c6e9	1513	case 0x01:
tax	0:66300c77c6e9	1514	/* NOP option. */
tax	0:66300c77c6e9	1515	++c;
tax	0:66300c77c6e9	1516	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: NOP\n"));
tax	0:66300c77c6e9	1517	break;
tax	0:66300c77c6e9	1518	case 0x02:
tax	0:66300c77c6e9	1519	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: MSS\n"));
tax	0:66300c77c6e9	1520	if (opts[c + 1] != 0x04 \|\| c + 0x04 > max_c) {
tax	0:66300c77c6e9	1521	/* Bad length */
tax	0:66300c77c6e9	1522	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
tax	0:66300c77c6e9	1523	return;
tax	0:66300c77c6e9	1524	}
tax	0:66300c77c6e9	1525	/* An MSS option with the right option length. */
tax	0:66300c77c6e9	1526	mss = (opts[c + 2] << 8) \| opts[c + 3];
tax	0:66300c77c6e9	1527	/* Limit the mss to the configured TCP_MSS and prevent division by zero */
tax	0:66300c77c6e9	1528	pcb->mss = ((mss > TCP_MSS) \|\| (mss == 0)) ? TCP_MSS : mss;
tax	0:66300c77c6e9	1529	/* Advance to next option */
tax	0:66300c77c6e9	1530	c += 0x04;
tax	0:66300c77c6e9	1531	break;
tax	0:66300c77c6e9	1532	#if LWIP_TCP_TIMESTAMPS
tax	0:66300c77c6e9	1533	case 0x08:
tax	0:66300c77c6e9	1534	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: TS\n"));
tax	0:66300c77c6e9	1535	if (opts[c + 1] != 0x0A \|\| c + 0x0A > max_c) {
tax	0:66300c77c6e9	1536	/* Bad length */
tax	0:66300c77c6e9	1537	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
tax	0:66300c77c6e9	1538	return;
tax	0:66300c77c6e9	1539	}
tax	0:66300c77c6e9	1540	/* TCP timestamp option with valid length */
tax	0:66300c77c6e9	1541	tsval = (opts[c+2]) \| (opts[c+3] << 8) \|
tax	0:66300c77c6e9	1542	(opts[c+4] << 16) \| (opts[c+5] << 24);
tax	0:66300c77c6e9	1543	if (flags & TCP_SYN) {
tax	0:66300c77c6e9	1544	pcb->ts_recent = ntohl(tsval);
tax	0:66300c77c6e9	1545	pcb->flags \|= TF_TIMESTAMP;
tax	0:66300c77c6e9	1546	} else if (TCP_SEQ_BETWEEN(pcb->ts_lastacksent, seqno, seqno+tcplen)) {
tax	0:66300c77c6e9	1547	pcb->ts_recent = ntohl(tsval);
tax	0:66300c77c6e9	1548	}
tax	0:66300c77c6e9	1549	/* Advance to next option */
tax	0:66300c77c6e9	1550	c += 0x0A;
tax	0:66300c77c6e9	1551	break;
tax	0:66300c77c6e9	1552	#endif
tax	0:66300c77c6e9	1553	default:
tax	0:66300c77c6e9	1554	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: other\n"));
tax	0:66300c77c6e9	1555	if (opts[c + 1] == 0) {
tax	0:66300c77c6e9	1556	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
tax	0:66300c77c6e9	1557	/* If the length field is zero, the options are malformed
tax	0:66300c77c6e9	1558	and we don't process them further. */
tax	0:66300c77c6e9	1559	return;
tax	0:66300c77c6e9	1560	}
tax	0:66300c77c6e9	1561	/* All other options have a length field, so that we easily
tax	0:66300c77c6e9	1562	can skip past them. */
tax	0:66300c77c6e9	1563	c += opts[c + 1];
tax	0:66300c77c6e9	1564	}
tax	0:66300c77c6e9	1565	}
tax	0:66300c77c6e9	1566	}
tax	0:66300c77c6e9	1567	}
tax	0:66300c77c6e9	1568
tax	0:66300c77c6e9	1569	#endif /* LWIP_TCP */

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	29 Mar 2011
Imports:	16
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	2

lwip/core/tcp_in.c@0:66300c77c6e9, 2011-03-29 (annotated)

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