iva2k_NetHttpServerTcpSockets - Example program with HTTPServer and sensor data s…

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Ilya I / Mbed 2 deprecated iva2k_NetHttpServerTcpSockets

Example program with HTTPServer and sensor data streaming over TCPSockets, using Donatien Garnier's Net APIs and services code on top of LWIP. Files StreamServer.h and .cpp encapsulate streaming over TCPSockets. Broadcast is done by sendToAll(), and all incoming data is echoed back to the client. Echo code can be replaced with some remote control of the streaming interface. See main() that shows how to periodically send some data to all subscribed clients. To subscribe, a client should open a socket at <mbed_ip> port 123. I used few lines in TCL code to set up a quick sink for the data. HTTP files are served on port 80 concurrently to the streaming.

Dependencies: mbed

lwip/core/tcp_in.c@1:3ee499525aa5, 2010-06-14 (annotated)

Committer:: iva2k
Date:: Mon Jun 14 03:24:33 2010 +0000
Revision:: 1:3ee499525aa5
Parent:: 0:e614f7875b60

Who changed what in which revision?

User	Revision	Line number	New contents of line
iva2k	0:e614f7875b60	1	/**
iva2k	0:e614f7875b60	2	* @file
iva2k	0:e614f7875b60	3	* Transmission Control Protocol, incoming traffic
iva2k	0:e614f7875b60	4	*
iva2k	0:e614f7875b60	5	* The input processing functions of the TCP layer.
iva2k	0:e614f7875b60	6	*
iva2k	0:e614f7875b60	7	* These functions are generally called in the order (ip_input() ->)
iva2k	0:e614f7875b60	8	* tcp_input() -> * tcp_process() -> tcp_receive() (-> application).
iva2k	0:e614f7875b60	9	*
iva2k	0:e614f7875b60	10	*/
iva2k	0:e614f7875b60	11
iva2k	0:e614f7875b60	12	/*
iva2k	0:e614f7875b60	13	* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
iva2k	0:e614f7875b60	14	* All rights reserved.
iva2k	0:e614f7875b60	15	*
iva2k	0:e614f7875b60	16	* Redistribution and use in source and binary forms, with or without modification,
iva2k	0:e614f7875b60	17	* are permitted provided that the following conditions are met:
iva2k	0:e614f7875b60	18	*
iva2k	0:e614f7875b60	19	* 1. Redistributions of source code must retain the above copyright notice,
iva2k	0:e614f7875b60	20	* this list of conditions and the following disclaimer.
iva2k	0:e614f7875b60	21	* 2. Redistributions in binary form must reproduce the above copyright notice,
iva2k	0:e614f7875b60	22	* this list of conditions and the following disclaimer in the documentation
iva2k	0:e614f7875b60	23	* and/or other materials provided with the distribution.
iva2k	0:e614f7875b60	24	* 3. The name of the author may not be used to endorse or promote products
iva2k	0:e614f7875b60	25	* derived from this software without specific prior written permission.
iva2k	0:e614f7875b60	26	*
iva2k	0:e614f7875b60	27	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
iva2k	0:e614f7875b60	28	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
iva2k	0:e614f7875b60	29	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
iva2k	0:e614f7875b60	30	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
iva2k	0:e614f7875b60	31	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
iva2k	0:e614f7875b60	32	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
iva2k	0:e614f7875b60	33	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
iva2k	0:e614f7875b60	34	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
iva2k	0:e614f7875b60	35	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
iva2k	0:e614f7875b60	36	* OF SUCH DAMAGE.
iva2k	0:e614f7875b60	37	*
iva2k	0:e614f7875b60	38	* This file is part of the lwIP TCP/IP stack.
iva2k	0:e614f7875b60	39	*
iva2k	0:e614f7875b60	40	* Author: Adam Dunkels <adam@sics.se>
iva2k	0:e614f7875b60	41	*
iva2k	0:e614f7875b60	42	*/
iva2k	0:e614f7875b60	43
iva2k	0:e614f7875b60	44	#include "lwip/opt.h"
iva2k	0:e614f7875b60	45
iva2k	0:e614f7875b60	46	#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
iva2k	0:e614f7875b60	47
iva2k	0:e614f7875b60	48	#include "lwip/tcp_impl.h"
iva2k	0:e614f7875b60	49	#include "lwip/def.h"
iva2k	0:e614f7875b60	50	#include "lwip/ip_addr.h"
iva2k	0:e614f7875b60	51	#include "lwip/netif.h"
iva2k	0:e614f7875b60	52	#include "lwip/mem.h"
iva2k	0:e614f7875b60	53	#include "lwip/memp.h"
iva2k	0:e614f7875b60	54	#include "lwip/inet_chksum.h"
iva2k	0:e614f7875b60	55	#include "lwip/stats.h"
iva2k	0:e614f7875b60	56	#include "lwip/snmp.h"
iva2k	0:e614f7875b60	57	#include "arch/perf.h"
iva2k	0:e614f7875b60	58
iva2k	0:e614f7875b60	59	/* These variables are global to all functions involved in the input
iva2k	0:e614f7875b60	60	processing of TCP segments. They are set by the tcp_input()
iva2k	0:e614f7875b60	61	function. */
iva2k	0:e614f7875b60	62	static struct tcp_seg inseg;
iva2k	0:e614f7875b60	63	static struct tcp_hdr *tcphdr;
iva2k	0:e614f7875b60	64	static struct ip_hdr *iphdr;
iva2k	0:e614f7875b60	65	static u32_t seqno, ackno;
iva2k	0:e614f7875b60	66	static u8_t flags;
iva2k	0:e614f7875b60	67	static u16_t tcplen;
iva2k	0:e614f7875b60	68
iva2k	0:e614f7875b60	69	static u8_t recv_flags;
iva2k	0:e614f7875b60	70	static struct pbuf *recv_data;
iva2k	0:e614f7875b60	71
iva2k	0:e614f7875b60	72	struct tcp_pcb *tcp_input_pcb;
iva2k	0:e614f7875b60	73
iva2k	0:e614f7875b60	74	/* Forward declarations. */
iva2k	0:e614f7875b60	75	static err_t tcp_process(struct tcp_pcb *pcb);
iva2k	0:e614f7875b60	76	static void tcp_receive(struct tcp_pcb *pcb);
iva2k	0:e614f7875b60	77	static void tcp_parseopt(struct tcp_pcb *pcb);
iva2k	0:e614f7875b60	78
iva2k	0:e614f7875b60	79	static err_t tcp_listen_input(struct tcp_pcb_listen *pcb);
iva2k	0:e614f7875b60	80	static err_t tcp_timewait_input(struct tcp_pcb *pcb);
iva2k	0:e614f7875b60	81
iva2k	0:e614f7875b60	82	/**
iva2k	0:e614f7875b60	83	* The initial input processing of TCP. It verifies the TCP header, demultiplexes
iva2k	0:e614f7875b60	84	* the segment between the PCBs and passes it on to tcp_process(), which implements
iva2k	0:e614f7875b60	85	* the TCP finite state machine. This function is called by the IP layer (in
iva2k	0:e614f7875b60	86	* ip_input()).
iva2k	0:e614f7875b60	87	*
iva2k	0:e614f7875b60	88	* @param p received TCP segment to process (p->payload pointing to the IP header)
iva2k	0:e614f7875b60	89	* @param inp network interface on which this segment was received
iva2k	0:e614f7875b60	90	*/
iva2k	0:e614f7875b60	91	void
iva2k	0:e614f7875b60	92	tcp_input(struct pbuf p, struct netif inp)
iva2k	0:e614f7875b60	93	{
iva2k	0:e614f7875b60	94	struct tcp_pcb pcb, prev;
iva2k	0:e614f7875b60	95	struct tcp_pcb_listen *lpcb;
iva2k	0:e614f7875b60	96	u8_t hdrlen;
iva2k	0:e614f7875b60	97	err_t err;
iva2k	0:e614f7875b60	98
iva2k	0:e614f7875b60	99	PERF_START;
iva2k	0:e614f7875b60	100
iva2k	0:e614f7875b60	101	TCP_STATS_INC(tcp.recv);
iva2k	0:e614f7875b60	102	snmp_inc_tcpinsegs();
iva2k	0:e614f7875b60	103
iva2k	0:e614f7875b60	104	iphdr = (struct ip_hdr *)p->payload;
iva2k	0:e614f7875b60	105	tcphdr = (struct tcp_hdr )((u8_t )p->payload + IPH_HL(iphdr) * 4);
iva2k	0:e614f7875b60	106
iva2k	0:e614f7875b60	107	#if TCP_INPUT_DEBUG
iva2k	0:e614f7875b60	108	tcp_debug_print(tcphdr);
iva2k	0:e614f7875b60	109	#endif
iva2k	0:e614f7875b60	110
iva2k	0:e614f7875b60	111	/* remove header from payload */
iva2k	0:e614f7875b60	112	if (pbuf_header(p, -((s16_t)(IPH_HL(iphdr) * 4))) \|\| (p->tot_len < sizeof(struct tcp_hdr))) {
iva2k	0:e614f7875b60	113	/* drop short packets */
iva2k	0:e614f7875b60	114	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: short packet (%"U16_F" bytes) discarded\n", p->tot_len));
iva2k	0:e614f7875b60	115	TCP_STATS_INC(tcp.lenerr);
iva2k	0:e614f7875b60	116	TCP_STATS_INC(tcp.drop);
iva2k	0:e614f7875b60	117	snmp_inc_tcpinerrs();
iva2k	0:e614f7875b60	118	pbuf_free(p);
iva2k	0:e614f7875b60	119	return;
iva2k	0:e614f7875b60	120	}
iva2k	0:e614f7875b60	121
iva2k	0:e614f7875b60	122	/* Don't even process incoming broadcasts/multicasts. */
iva2k	0:e614f7875b60	123	if (ip_addr_isbroadcast(&(iphdr->dest), inp) \|\|
iva2k	0:e614f7875b60	124	ip_addr_ismulticast(&(iphdr->dest))) {
iva2k	0:e614f7875b60	125	TCP_STATS_INC(tcp.proterr);
iva2k	0:e614f7875b60	126	TCP_STATS_INC(tcp.drop);
iva2k	0:e614f7875b60	127	snmp_inc_tcpinerrs();
iva2k	0:e614f7875b60	128	pbuf_free(p);
iva2k	0:e614f7875b60	129	return;
iva2k	0:e614f7875b60	130	}
iva2k	0:e614f7875b60	131
iva2k	0:e614f7875b60	132	#if CHECKSUM_CHECK_TCP
iva2k	0:e614f7875b60	133	/* Verify TCP checksum. */
iva2k	0:e614f7875b60	134	if (inet_chksum_pseudo(p, &iphdr->src, &iphdr->dest,
iva2k	0:e614f7875b60	135	IP_PROTO_TCP, p->tot_len) != 0) {
iva2k	0:e614f7875b60	136	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packet discarded due to failing checksum 0x%04"X16_F"\n",
iva2k	0:e614f7875b60	137	inet_chksum_pseudo(p, &iphdr->src, &iphdr->dest,
iva2k	0:e614f7875b60	138	IP_PROTO_TCP, p->tot_len)));
iva2k	0:e614f7875b60	139	#if TCP_DEBUG
iva2k	0:e614f7875b60	140	tcp_debug_print(tcphdr);
iva2k	0:e614f7875b60	141	#endif /* TCP_DEBUG */
iva2k	0:e614f7875b60	142	TCP_STATS_INC(tcp.chkerr);
iva2k	0:e614f7875b60	143	TCP_STATS_INC(tcp.drop);
iva2k	0:e614f7875b60	144	snmp_inc_tcpinerrs();
iva2k	0:e614f7875b60	145	pbuf_free(p);
iva2k	0:e614f7875b60	146	return;
iva2k	0:e614f7875b60	147	}
iva2k	0:e614f7875b60	148	#endif
iva2k	0:e614f7875b60	149
iva2k	0:e614f7875b60	150	/* Move the payload pointer in the pbuf so that it points to the
iva2k	0:e614f7875b60	151	TCP data instead of the TCP header. */
iva2k	0:e614f7875b60	152	hdrlen = TCPH_HDRLEN(tcphdr);
iva2k	0:e614f7875b60	153	if(pbuf_header(p, -(hdrlen * 4))){
iva2k	0:e614f7875b60	154	/* drop short packets */
iva2k	0:e614f7875b60	155	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: short packet\n"));
iva2k	0:e614f7875b60	156	TCP_STATS_INC(tcp.lenerr);
iva2k	0:e614f7875b60	157	TCP_STATS_INC(tcp.drop);
iva2k	0:e614f7875b60	158	snmp_inc_tcpinerrs();
iva2k	0:e614f7875b60	159	pbuf_free(p);
iva2k	0:e614f7875b60	160	return;
iva2k	0:e614f7875b60	161	}
iva2k	0:e614f7875b60	162
iva2k	0:e614f7875b60	163	/* Convert fields in TCP header to host byte order. */
iva2k	0:e614f7875b60	164	tcphdr->src = ntohs(tcphdr->src);
iva2k	0:e614f7875b60	165	tcphdr->dest = ntohs(tcphdr->dest);
iva2k	0:e614f7875b60	166	seqno = tcphdr->seqno = ntohl(tcphdr->seqno);
iva2k	0:e614f7875b60	167	ackno = tcphdr->ackno = ntohl(tcphdr->ackno);
iva2k	0:e614f7875b60	168	tcphdr->wnd = ntohs(tcphdr->wnd);
iva2k	0:e614f7875b60	169
iva2k	0:e614f7875b60	170	flags = TCPH_FLAGS(tcphdr);
iva2k	0:e614f7875b60	171	tcplen = p->tot_len + ((flags & (TCP_FIN \| TCP_SYN)) ? 1 : 0);
iva2k	0:e614f7875b60	172
iva2k	0:e614f7875b60	173	/* Demultiplex an incoming segment. First, we check if it is destined
iva2k	0:e614f7875b60	174	for an active connection. */
iva2k	0:e614f7875b60	175	prev = NULL;
iva2k	0:e614f7875b60	176
iva2k	0:e614f7875b60	177
iva2k	0:e614f7875b60	178	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
iva2k	0:e614f7875b60	179	LWIP_ASSERT("tcp_input: active pcb->state != CLOSED", pcb->state != CLOSED);
iva2k	0:e614f7875b60	180	LWIP_ASSERT("tcp_input: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
iva2k	0:e614f7875b60	181	LWIP_ASSERT("tcp_input: active pcb->state != LISTEN", pcb->state != LISTEN);
iva2k	0:e614f7875b60	182	if (pcb->remote_port == tcphdr->src &&
iva2k	0:e614f7875b60	183	pcb->local_port == tcphdr->dest &&
iva2k	0:e614f7875b60	184	ip_addr_cmp(&(pcb->remote_ip), &(iphdr->src)) &&
iva2k	0:e614f7875b60	185	ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest))) {
iva2k	0:e614f7875b60	186
iva2k	0:e614f7875b60	187	/* Move this PCB to the front of the list so that subsequent
iva2k	0:e614f7875b60	188	lookups will be faster (we exploit locality in TCP segment
iva2k	0:e614f7875b60	189	arrivals). */
iva2k	0:e614f7875b60	190	LWIP_ASSERT("tcp_input: pcb->next != pcb (before cache)", pcb->next != pcb);
iva2k	0:e614f7875b60	191	if (prev != NULL) {
iva2k	0:e614f7875b60	192	prev->next = pcb->next;
iva2k	0:e614f7875b60	193	pcb->next = tcp_active_pcbs;
iva2k	0:e614f7875b60	194	tcp_active_pcbs = pcb;
iva2k	0:e614f7875b60	195	}
iva2k	0:e614f7875b60	196	LWIP_ASSERT("tcp_input: pcb->next != pcb (after cache)", pcb->next != pcb);
iva2k	0:e614f7875b60	197	break;
iva2k	0:e614f7875b60	198	}
iva2k	0:e614f7875b60	199	prev = pcb;
iva2k	0:e614f7875b60	200	}
iva2k	0:e614f7875b60	201
iva2k	0:e614f7875b60	202	if (pcb == NULL) {
iva2k	0:e614f7875b60	203	/* If it did not go to an active connection, we check the connections
iva2k	0:e614f7875b60	204	in the TIME-WAIT state. */
iva2k	0:e614f7875b60	205	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
iva2k	0:e614f7875b60	206	LWIP_ASSERT("tcp_input: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
iva2k	0:e614f7875b60	207	if (pcb->remote_port == tcphdr->src &&
iva2k	0:e614f7875b60	208	pcb->local_port == tcphdr->dest &&
iva2k	0:e614f7875b60	209	ip_addr_cmp(&(pcb->remote_ip), &(iphdr->src)) &&
iva2k	0:e614f7875b60	210	ip_addr_cmp(&(pcb->local_ip), &(iphdr->dest))) {
iva2k	0:e614f7875b60	211	/* We don't really care enough to move this PCB to the front
iva2k	0:e614f7875b60	212	of the list since we are not very likely to receive that
iva2k	0:e614f7875b60	213	many segments for connections in TIME-WAIT. */
iva2k	0:e614f7875b60	214	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packed for TIME_WAITing connection.\n"));
iva2k	0:e614f7875b60	215	tcp_timewait_input(pcb);
iva2k	0:e614f7875b60	216	pbuf_free(p);
iva2k	0:e614f7875b60	217	return;
iva2k	0:e614f7875b60	218	}
iva2k	0:e614f7875b60	219	}
iva2k	0:e614f7875b60	220
iva2k	0:e614f7875b60	221	/* Finally, if we still did not get a match, we check all PCBs that
iva2k	0:e614f7875b60	222	are LISTENing for incoming connections. */
iva2k	0:e614f7875b60	223	prev = NULL;
iva2k	0:e614f7875b60	224	for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
iva2k	0:e614f7875b60	225	if ((ip_addr_isany(&(lpcb->local_ip)) \|\|
iva2k	0:e614f7875b60	226	ip_addr_cmp(&(lpcb->local_ip), &(iphdr->dest))) &&
iva2k	0:e614f7875b60	227	lpcb->local_port == tcphdr->dest) {
iva2k	0:e614f7875b60	228	/* Move this PCB to the front of the list so that subsequent
iva2k	0:e614f7875b60	229	lookups will be faster (we exploit locality in TCP segment
iva2k	0:e614f7875b60	230	arrivals). */
iva2k	0:e614f7875b60	231	if (prev != NULL) {
iva2k	0:e614f7875b60	232	((struct tcp_pcb_listen *)prev)->next = lpcb->next;
iva2k	0:e614f7875b60	233	/* our successor is the remainder of the listening list */
iva2k	0:e614f7875b60	234	lpcb->next = tcp_listen_pcbs.listen_pcbs;
iva2k	0:e614f7875b60	235	/* put this listening pcb at the head of the listening list */
iva2k	0:e614f7875b60	236	tcp_listen_pcbs.listen_pcbs = lpcb;
iva2k	0:e614f7875b60	237	}
iva2k	0:e614f7875b60	238
iva2k	0:e614f7875b60	239	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: packed for LISTENing connection.\n"));
iva2k	0:e614f7875b60	240	tcp_listen_input(lpcb);
iva2k	0:e614f7875b60	241	pbuf_free(p);
iva2k	0:e614f7875b60	242	return;
iva2k	0:e614f7875b60	243	}
iva2k	0:e614f7875b60	244	prev = (struct tcp_pcb *)lpcb;
iva2k	0:e614f7875b60	245	}
iva2k	0:e614f7875b60	246	}
iva2k	0:e614f7875b60	247
iva2k	0:e614f7875b60	248	#if TCP_INPUT_DEBUG
iva2k	0:e614f7875b60	249	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("+-+-+-+-+-+-+-+-+-+-+-+-+-+- tcp_input: flags "));
iva2k	0:e614f7875b60	250	tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
iva2k	0:e614f7875b60	251	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("-+-+-+-+-+-+-+-+-+-+-+-+-+-+\n"));
iva2k	0:e614f7875b60	252	#endif /* TCP_INPUT_DEBUG */
iva2k	0:e614f7875b60	253
iva2k	0:e614f7875b60	254
iva2k	0:e614f7875b60	255	if (pcb != NULL) {
iva2k	0:e614f7875b60	256	/* The incoming segment belongs to a connection. */
iva2k	0:e614f7875b60	257	#if TCP_INPUT_DEBUG
iva2k	0:e614f7875b60	258	#if TCP_DEBUG
iva2k	0:e614f7875b60	259	tcp_debug_print_state(pcb->state);
iva2k	0:e614f7875b60	260	#endif /* TCP_DEBUG */
iva2k	0:e614f7875b60	261	#endif /* TCP_INPUT_DEBUG */
iva2k	0:e614f7875b60	262
iva2k	0:e614f7875b60	263	/* Set up a tcp_seg structure. */
iva2k	0:e614f7875b60	264	inseg.next = NULL;
iva2k	0:e614f7875b60	265	inseg.len = p->tot_len;
iva2k	0:e614f7875b60	266	inseg.dataptr = p->payload;
iva2k	0:e614f7875b60	267	inseg.p = p;
iva2k	0:e614f7875b60	268	inseg.tcphdr = tcphdr;
iva2k	0:e614f7875b60	269
iva2k	0:e614f7875b60	270	recv_data = NULL;
iva2k	0:e614f7875b60	271	recv_flags = 0;
iva2k	0:e614f7875b60	272
iva2k	0:e614f7875b60	273	/* If there is data which was previously "refused" by upper layer */
iva2k	0:e614f7875b60	274	if (pcb->refused_data != NULL) {
iva2k	0:e614f7875b60	275	/* Notify again application with data previously received. */
iva2k	0:e614f7875b60	276	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: notify kept packet\n"));
iva2k	0:e614f7875b60	277	TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
iva2k	0:e614f7875b60	278	if (err == ERR_OK) {
iva2k	0:e614f7875b60	279	pcb->refused_data = NULL;
iva2k	0:e614f7875b60	280	} else {
iva2k	0:e614f7875b60	281	/* if err == ERR_ABRT, 'pcb' is already deallocated */
iva2k	0:e614f7875b60	282	/* drop incoming packets, because pcb is "full" */
iva2k	0:e614f7875b60	283	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: drop incoming packets, because pcb is \"full\"\n"));
iva2k	0:e614f7875b60	284	TCP_STATS_INC(tcp.drop);
iva2k	0:e614f7875b60	285	snmp_inc_tcpinerrs();
iva2k	0:e614f7875b60	286	pbuf_free(p);
iva2k	0:e614f7875b60	287	return;
iva2k	0:e614f7875b60	288	}
iva2k	0:e614f7875b60	289	}
iva2k	0:e614f7875b60	290	tcp_input_pcb = pcb;
iva2k	0:e614f7875b60	291	err = tcp_process(pcb);
iva2k	0:e614f7875b60	292	/* A return value of ERR_ABRT means that tcp_abort() was called
iva2k	0:e614f7875b60	293	and that the pcb has been freed. If so, we don't do anything. */
iva2k	0:e614f7875b60	294	if (err != ERR_ABRT) {
iva2k	0:e614f7875b60	295	if (recv_flags & TF_RESET) {
iva2k	0:e614f7875b60	296	/* TF_RESET means that the connection was reset by the other
iva2k	0:e614f7875b60	297	end. We then call the error callback to inform the
iva2k	0:e614f7875b60	298	application that the connection is dead before we
iva2k	0:e614f7875b60	299	deallocate the PCB. */
iva2k	0:e614f7875b60	300	TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_RST);
iva2k	0:e614f7875b60	301	tcp_pcb_remove(&tcp_active_pcbs, pcb);
iva2k	0:e614f7875b60	302	memp_free(MEMP_TCP_PCB, pcb);
iva2k	0:e614f7875b60	303	} else if (recv_flags & TF_CLOSED) {
iva2k	0:e614f7875b60	304	/* The connection has been closed and we will deallocate the
iva2k	0:e614f7875b60	305	PCB. */
iva2k	0:e614f7875b60	306	tcp_pcb_remove(&tcp_active_pcbs, pcb);
iva2k	0:e614f7875b60	307	memp_free(MEMP_TCP_PCB, pcb);
iva2k	0:e614f7875b60	308	} else {
iva2k	0:e614f7875b60	309	err = ERR_OK;
iva2k	0:e614f7875b60	310	/* If the application has registered a "sent" function to be
iva2k	0:e614f7875b60	311	called when new send buffer space is available, we call it
iva2k	0:e614f7875b60	312	now. */
iva2k	0:e614f7875b60	313	if (pcb->acked > 0) {
iva2k	0:e614f7875b60	314	TCP_EVENT_SENT(pcb, pcb->acked, err);
iva2k	0:e614f7875b60	315	if (err == ERR_ABRT) {
iva2k	0:e614f7875b60	316	goto aborted;
iva2k	0:e614f7875b60	317	}
iva2k	0:e614f7875b60	318	}
iva2k	0:e614f7875b60	319
iva2k	0:e614f7875b60	320	if (recv_data != NULL) {
iva2k	0:e614f7875b60	321	if(flags & TCP_PSH) {
iva2k	0:e614f7875b60	322	recv_data->flags \|= PBUF_FLAG_PUSH;
iva2k	0:e614f7875b60	323	}
iva2k	0:e614f7875b60	324
iva2k	0:e614f7875b60	325	/* Notify application that data has been received. */
iva2k	0:e614f7875b60	326	TCP_EVENT_RECV(pcb, recv_data, ERR_OK, err);
iva2k	0:e614f7875b60	327	if (err == ERR_ABRT) {
iva2k	0:e614f7875b60	328	goto aborted;
iva2k	0:e614f7875b60	329	}
iva2k	0:e614f7875b60	330
iva2k	0:e614f7875b60	331	/* If the upper layer can't receive this data, store it */
iva2k	0:e614f7875b60	332	if (err != ERR_OK) {
iva2k	0:e614f7875b60	333	pcb->refused_data = recv_data;
iva2k	0:e614f7875b60	334	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_input: keep incoming packet, because pcb is \"full\"\n"));
iva2k	0:e614f7875b60	335	}
iva2k	0:e614f7875b60	336	}
iva2k	0:e614f7875b60	337
iva2k	0:e614f7875b60	338	/* If a FIN segment was received, we call the callback
iva2k	0:e614f7875b60	339	function with a NULL buffer to indicate EOF. */
iva2k	0:e614f7875b60	340	if (recv_flags & TF_GOT_FIN) {
iva2k	0:e614f7875b60	341	/* correct rcv_wnd as the application won't call tcp_recved()
iva2k	0:e614f7875b60	342	for the FIN's seqno */
iva2k	0:e614f7875b60	343	if (pcb->rcv_wnd != TCP_WND) {
iva2k	0:e614f7875b60	344	pcb->rcv_wnd++;
iva2k	0:e614f7875b60	345	}
iva2k	0:e614f7875b60	346	TCP_EVENT_RECV(pcb, NULL, ERR_OK, err);
iva2k	0:e614f7875b60	347	if (err == ERR_ABRT) {
iva2k	0:e614f7875b60	348	goto aborted;
iva2k	0:e614f7875b60	349	}
iva2k	0:e614f7875b60	350	}
iva2k	0:e614f7875b60	351
iva2k	0:e614f7875b60	352	tcp_input_pcb = NULL;
iva2k	0:e614f7875b60	353	/* Try to send something out. */
iva2k	0:e614f7875b60	354	tcp_output(pcb);
iva2k	0:e614f7875b60	355	#if TCP_INPUT_DEBUG
iva2k	0:e614f7875b60	356	#if TCP_DEBUG
iva2k	0:e614f7875b60	357	tcp_debug_print_state(pcb->state);
iva2k	0:e614f7875b60	358	#endif /* TCP_DEBUG */
iva2k	0:e614f7875b60	359	#endif /* TCP_INPUT_DEBUG */
iva2k	0:e614f7875b60	360	}
iva2k	0:e614f7875b60	361	}
iva2k	0:e614f7875b60	362	/* Jump target if pcb has been aborted in a callback (by calling tcp_abort()).
iva2k	0:e614f7875b60	363	Below this line, 'pcb' may not be dereferenced! */
iva2k	0:e614f7875b60	364	aborted:
iva2k	0:e614f7875b60	365	tcp_input_pcb = NULL;
iva2k	0:e614f7875b60	366
iva2k	0:e614f7875b60	367
iva2k	0:e614f7875b60	368	/* give up our reference to inseg.p */
iva2k	0:e614f7875b60	369	if (inseg.p != NULL)
iva2k	0:e614f7875b60	370	{
iva2k	0:e614f7875b60	371	pbuf_free(inseg.p);
iva2k	0:e614f7875b60	372	inseg.p = NULL;
iva2k	0:e614f7875b60	373	}
iva2k	0:e614f7875b60	374	} else {
iva2k	0:e614f7875b60	375
iva2k	0:e614f7875b60	376	/* If no matching PCB was found, send a TCP RST (reset) to the
iva2k	0:e614f7875b60	377	sender. */
iva2k	0:e614f7875b60	378	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_input: no PCB match found, resetting.\n"));
iva2k	0:e614f7875b60	379	if (!(TCPH_FLAGS(tcphdr) & TCP_RST)) {
iva2k	0:e614f7875b60	380	TCP_STATS_INC(tcp.proterr);
iva2k	0:e614f7875b60	381	TCP_STATS_INC(tcp.drop);
iva2k	0:e614f7875b60	382	tcp_rst(ackno, seqno + tcplen,
iva2k	0:e614f7875b60	383	&(iphdr->dest), &(iphdr->src),
iva2k	0:e614f7875b60	384	tcphdr->dest, tcphdr->src);
iva2k	0:e614f7875b60	385	}
iva2k	0:e614f7875b60	386	pbuf_free(p);
iva2k	0:e614f7875b60	387	}
iva2k	0:e614f7875b60	388
iva2k	0:e614f7875b60	389	LWIP_ASSERT("tcp_input: tcp_pcbs_sane()", tcp_pcbs_sane());
iva2k	0:e614f7875b60	390	PERF_STOP("tcp_input");
iva2k	0:e614f7875b60	391	}
iva2k	0:e614f7875b60	392
iva2k	0:e614f7875b60	393	/**
iva2k	0:e614f7875b60	394	* Called by tcp_input() when a segment arrives for a listening
iva2k	0:e614f7875b60	395	* connection (from tcp_input()).
iva2k	0:e614f7875b60	396	*
iva2k	0:e614f7875b60	397	* @param pcb the tcp_pcb_listen for which a segment arrived
iva2k	0:e614f7875b60	398	* @return ERR_OK if the segment was processed
iva2k	0:e614f7875b60	399	* another err_t on error
iva2k	0:e614f7875b60	400	*
iva2k	0:e614f7875b60	401	* @note the return value is not (yet?) used in tcp_input()
iva2k	0:e614f7875b60	402	* @note the segment which arrived is saved in global variables, therefore only the pcb
iva2k	0:e614f7875b60	403	* involved is passed as a parameter to this function
iva2k	0:e614f7875b60	404	*/
iva2k	0:e614f7875b60	405	static err_t
iva2k	0:e614f7875b60	406	tcp_listen_input(struct tcp_pcb_listen *pcb)
iva2k	0:e614f7875b60	407	{
iva2k	0:e614f7875b60	408	struct tcp_pcb *npcb;
iva2k	0:e614f7875b60	409	err_t rc;
iva2k	0:e614f7875b60	410
iva2k	0:e614f7875b60	411	/* In the LISTEN state, we check for incoming SYN segments,
iva2k	0:e614f7875b60	412	creates a new PCB, and responds with a SYN\|ACK. */
iva2k	0:e614f7875b60	413	if (flags & TCP_ACK) {
iva2k	0:e614f7875b60	414	/* For incoming segments with the ACK flag set, respond with a
iva2k	0:e614f7875b60	415	RST. */
iva2k	0:e614f7875b60	416	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_listen_input: ACK in LISTEN, sending reset\n"));
iva2k	0:e614f7875b60	417	tcp_rst(ackno + 1, seqno + tcplen,
iva2k	0:e614f7875b60	418	&(iphdr->dest), &(iphdr->src),
iva2k	0:e614f7875b60	419	tcphdr->dest, tcphdr->src);
iva2k	0:e614f7875b60	420	} else if (flags & TCP_SYN) {
iva2k	0:e614f7875b60	421	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection request %"U16_F" -> %"U16_F".\n", tcphdr->src, tcphdr->dest));
iva2k	0:e614f7875b60	422	#if TCP_LISTEN_BACKLOG
iva2k	0:e614f7875b60	423	if (pcb->accepts_pending >= pcb->backlog) {
iva2k	0:e614f7875b60	424	LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: listen backlog exceeded for port %"U16_F"\n", tcphdr->dest));
iva2k	0:e614f7875b60	425	return ERR_ABRT;
iva2k	0:e614f7875b60	426	}
iva2k	0:e614f7875b60	427	#endif /* TCP_LISTEN_BACKLOG */
iva2k	0:e614f7875b60	428	npcb = tcp_alloc(pcb->prio);
iva2k	0:e614f7875b60	429	/* If a new PCB could not be created (probably due to lack of memory),
iva2k	0:e614f7875b60	430	we don't do anything, but rely on the sender will retransmit the
iva2k	0:e614f7875b60	431	SYN at a time when we have more memory available. */
iva2k	0:e614f7875b60	432	if (npcb == NULL) {
iva2k	0:e614f7875b60	433	LWIP_DEBUGF(TCP_DEBUG, ("tcp_listen_input: could not allocate PCB\n"));
iva2k	0:e614f7875b60	434	TCP_STATS_INC(tcp.memerr);
iva2k	0:e614f7875b60	435	return ERR_MEM;
iva2k	0:e614f7875b60	436	}
iva2k	0:e614f7875b60	437	#if TCP_LISTEN_BACKLOG
iva2k	0:e614f7875b60	438	pcb->accepts_pending++;
iva2k	0:e614f7875b60	439	#endif /* TCP_LISTEN_BACKLOG */
iva2k	0:e614f7875b60	440	/* Set up the new PCB. */
iva2k	0:e614f7875b60	441	ip_addr_copy(npcb->local_ip, iphdr->dest);
iva2k	0:e614f7875b60	442	npcb->local_port = pcb->local_port;
iva2k	0:e614f7875b60	443	ip_addr_copy(npcb->remote_ip, iphdr->src);
iva2k	0:e614f7875b60	444	npcb->remote_port = tcphdr->src;
iva2k	0:e614f7875b60	445	npcb->state = SYN_RCVD;
iva2k	0:e614f7875b60	446	npcb->rcv_nxt = seqno + 1;
iva2k	0:e614f7875b60	447	npcb->rcv_ann_right_edge = npcb->rcv_nxt;
iva2k	0:e614f7875b60	448	npcb->snd_wnd = tcphdr->wnd;
iva2k	0:e614f7875b60	449	npcb->ssthresh = npcb->snd_wnd;
iva2k	0:e614f7875b60	450	npcb->snd_wl1 = seqno - 1;/* initialise to seqno-1 to force window update */
iva2k	0:e614f7875b60	451	npcb->callback_arg = pcb->callback_arg;
iva2k	0:e614f7875b60	452	#if LWIP_CALLBACK_API
iva2k	0:e614f7875b60	453	npcb->accept = pcb->accept;
iva2k	0:e614f7875b60	454	#endif /* LWIP_CALLBACK_API */
iva2k	0:e614f7875b60	455	/* inherit socket options */
iva2k	0:e614f7875b60	456	npcb->so_options = pcb->so_options & (SOF_DEBUG\|SOF_DONTROUTE\|SOF_KEEPALIVE\|SOF_OOBINLINE\|SOF_LINGER);
iva2k	0:e614f7875b60	457	/* Register the new PCB so that we can begin receiving segments
iva2k	0:e614f7875b60	458	for it. */
iva2k	0:e614f7875b60	459	TCP_REG(&tcp_active_pcbs, npcb);
iva2k	0:e614f7875b60	460
iva2k	0:e614f7875b60	461	/* Parse any options in the SYN. */
iva2k	0:e614f7875b60	462	tcp_parseopt(npcb);
iva2k	0:e614f7875b60	463	#if TCP_CALCULATE_EFF_SEND_MSS
iva2k	0:e614f7875b60	464	npcb->mss = tcp_eff_send_mss(npcb->mss, &(npcb->remote_ip));
iva2k	0:e614f7875b60	465	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
iva2k	0:e614f7875b60	466
iva2k	0:e614f7875b60	467	snmp_inc_tcppassiveopens();
iva2k	0:e614f7875b60	468
iva2k	0:e614f7875b60	469	/* Send a SYN\|ACK together with the MSS option. */
iva2k	0:e614f7875b60	470	rc = tcp_enqueue_flags(npcb, TCP_SYN \| TCP_ACK);
iva2k	0:e614f7875b60	471	if (rc != ERR_OK) {
iva2k	0:e614f7875b60	472	tcp_abandon(npcb, 0);
iva2k	0:e614f7875b60	473	return rc;
iva2k	0:e614f7875b60	474	}
iva2k	0:e614f7875b60	475	return tcp_output(npcb);
iva2k	0:e614f7875b60	476	}
iva2k	0:e614f7875b60	477	return ERR_OK;
iva2k	0:e614f7875b60	478	}
iva2k	0:e614f7875b60	479
iva2k	0:e614f7875b60	480	/**
iva2k	0:e614f7875b60	481	* Called by tcp_input() when a segment arrives for a connection in
iva2k	0:e614f7875b60	482	* TIME_WAIT.
iva2k	0:e614f7875b60	483	*
iva2k	0:e614f7875b60	484	* @param pcb the tcp_pcb for which a segment arrived
iva2k	0:e614f7875b60	485	*
iva2k	0:e614f7875b60	486	* @note the segment which arrived is saved in global variables, therefore only the pcb
iva2k	0:e614f7875b60	487	* involved is passed as a parameter to this function
iva2k	0:e614f7875b60	488	*/
iva2k	0:e614f7875b60	489	static err_t
iva2k	0:e614f7875b60	490	tcp_timewait_input(struct tcp_pcb *pcb)
iva2k	0:e614f7875b60	491	{
iva2k	0:e614f7875b60	492	/* RFC 1337: in TIME_WAIT, ignore RST and ACK FINs + any 'acceptable' segments */
iva2k	0:e614f7875b60	493	/* RFC 793 3.9 Event Processing - Segment Arrives:
iva2k	0:e614f7875b60	494	* - first check sequence number - we skip that one in TIME_WAIT (always
iva2k	0:e614f7875b60	495	* acceptable since we only send ACKs)
iva2k	0:e614f7875b60	496	* - second check the RST bit (... return) */
iva2k	0:e614f7875b60	497	if (flags & TCP_RST) {
iva2k	0:e614f7875b60	498	return ERR_OK;
iva2k	0:e614f7875b60	499	}
iva2k	0:e614f7875b60	500	/* - fourth, check the SYN bit, */
iva2k	0:e614f7875b60	501	if (flags & TCP_SYN) {
iva2k	0:e614f7875b60	502	/* If an incoming segment is not acceptable, an acknowledgment
iva2k	0:e614f7875b60	503	should be sent in reply */
iva2k	0:e614f7875b60	504	if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt+pcb->rcv_wnd)) {
iva2k	0:e614f7875b60	505	/* If the SYN is in the window it is an error, send a reset */
iva2k	0:e614f7875b60	506	tcp_rst(ackno, seqno + tcplen, &(iphdr->dest), &(iphdr->src),
iva2k	0:e614f7875b60	507	tcphdr->dest, tcphdr->src);
iva2k	0:e614f7875b60	508	return ERR_OK;
iva2k	0:e614f7875b60	509	}
iva2k	0:e614f7875b60	510	} else if (flags & TCP_FIN) {
iva2k	0:e614f7875b60	511	/* - eighth, check the FIN bit: Remain in the TIME-WAIT state.
iva2k	0:e614f7875b60	512	Restart the 2 MSL time-wait timeout.*/
iva2k	0:e614f7875b60	513	pcb->tmr = tcp_ticks;
iva2k	0:e614f7875b60	514	}
iva2k	0:e614f7875b60	515
iva2k	0:e614f7875b60	516	if ((tcplen > 0)) {
iva2k	0:e614f7875b60	517	/* Acknowledge data, FIN or out-of-window SYN */
iva2k	0:e614f7875b60	518	pcb->flags \|= TF_ACK_NOW;
iva2k	0:e614f7875b60	519	return tcp_output(pcb);
iva2k	0:e614f7875b60	520	}
iva2k	0:e614f7875b60	521	return ERR_OK;
iva2k	0:e614f7875b60	522	}
iva2k	0:e614f7875b60	523
iva2k	0:e614f7875b60	524	/**
iva2k	0:e614f7875b60	525	* Implements the TCP state machine. Called by tcp_input. In some
iva2k	0:e614f7875b60	526	* states tcp_receive() is called to receive data. The tcp_seg
iva2k	0:e614f7875b60	527	* argument will be freed by the caller (tcp_input()) unless the
iva2k	0:e614f7875b60	528	* recv_data pointer in the pcb is set.
iva2k	0:e614f7875b60	529	*
iva2k	0:e614f7875b60	530	* @param pcb the tcp_pcb for which a segment arrived
iva2k	0:e614f7875b60	531	*
iva2k	0:e614f7875b60	532	* @note the segment which arrived is saved in global variables, therefore only the pcb
iva2k	0:e614f7875b60	533	* involved is passed as a parameter to this function
iva2k	0:e614f7875b60	534	*/
iva2k	0:e614f7875b60	535	static err_t
iva2k	0:e614f7875b60	536	tcp_process(struct tcp_pcb *pcb)
iva2k	0:e614f7875b60	537	{
iva2k	0:e614f7875b60	538	struct tcp_seg *rseg;
iva2k	0:e614f7875b60	539	u8_t acceptable = 0;
iva2k	0:e614f7875b60	540	err_t err;
iva2k	0:e614f7875b60	541
iva2k	0:e614f7875b60	542	err = ERR_OK;
iva2k	0:e614f7875b60	543
iva2k	0:e614f7875b60	544	/* Process incoming RST segments. */
iva2k	0:e614f7875b60	545	if (flags & TCP_RST) {
iva2k	0:e614f7875b60	546	/* First, determine if the reset is acceptable. */
iva2k	0:e614f7875b60	547	if (pcb->state == SYN_SENT) {
iva2k	0:e614f7875b60	548	if (ackno == pcb->snd_nxt) {
iva2k	0:e614f7875b60	549	acceptable = 1;
iva2k	0:e614f7875b60	550	}
iva2k	0:e614f7875b60	551	} else {
iva2k	0:e614f7875b60	552	if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt,
iva2k	0:e614f7875b60	553	pcb->rcv_nxt+pcb->rcv_wnd)) {
iva2k	0:e614f7875b60	554	acceptable = 1;
iva2k	0:e614f7875b60	555	}
iva2k	0:e614f7875b60	556	}
iva2k	0:e614f7875b60	557
iva2k	0:e614f7875b60	558	if (acceptable) {
iva2k	0:e614f7875b60	559	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_process: Connection RESET\n"));
iva2k	0:e614f7875b60	560	LWIP_ASSERT("tcp_input: pcb->state != CLOSED", pcb->state != CLOSED);
iva2k	0:e614f7875b60	561	recv_flags \|= TF_RESET;
iva2k	0:e614f7875b60	562	pcb->flags &= ~TF_ACK_DELAY;
iva2k	0:e614f7875b60	563	return ERR_RST;
iva2k	0:e614f7875b60	564	} else {
iva2k	0:e614f7875b60	565	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_process: unacceptable reset seqno %"U32_F" rcv_nxt %"U32_F"\n",
iva2k	0:e614f7875b60	566	seqno, pcb->rcv_nxt));
iva2k	0:e614f7875b60	567	LWIP_DEBUGF(TCP_DEBUG, ("tcp_process: unacceptable reset seqno %"U32_F" rcv_nxt %"U32_F"\n",
iva2k	0:e614f7875b60	568	seqno, pcb->rcv_nxt));
iva2k	0:e614f7875b60	569	return ERR_OK;
iva2k	0:e614f7875b60	570	}
iva2k	0:e614f7875b60	571	}
iva2k	0:e614f7875b60	572
iva2k	0:e614f7875b60	573	if ((flags & TCP_SYN) && (pcb->state != SYN_SENT && pcb->state != SYN_RCVD)) {
iva2k	0:e614f7875b60	574	/* Cope with new connection attempt after remote end crashed */
iva2k	0:e614f7875b60	575	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	576	return ERR_OK;
iva2k	0:e614f7875b60	577	}
iva2k	0:e614f7875b60	578
iva2k	0:e614f7875b60	579	if ((pcb->flags & TF_RXCLOSED) == 0) {
iva2k	0:e614f7875b60	580	/* Update the PCB (in)activity timer unless rx is closed (see tcp_shutdown) */
iva2k	0:e614f7875b60	581	pcb->tmr = tcp_ticks;
iva2k	0:e614f7875b60	582	}
iva2k	0:e614f7875b60	583	pcb->keep_cnt_sent = 0;
iva2k	0:e614f7875b60	584
iva2k	0:e614f7875b60	585	tcp_parseopt(pcb);
iva2k	0:e614f7875b60	586
iva2k	0:e614f7875b60	587	/* Do different things depending on the TCP state. */
iva2k	0:e614f7875b60	588	switch (pcb->state) {
iva2k	0:e614f7875b60	589	case SYN_SENT:
iva2k	0:e614f7875b60	590	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("SYN-SENT: ackno %"U32_F" pcb->snd_nxt %"U32_F" unacked %"U32_F"\n", ackno,
iva2k	0:e614f7875b60	591	pcb->snd_nxt, ntohl(pcb->unacked->tcphdr->seqno)));
iva2k	0:e614f7875b60	592	/* received SYN ACK with expected sequence number? */
iva2k	0:e614f7875b60	593	if ((flags & TCP_ACK) && (flags & TCP_SYN)
iva2k	0:e614f7875b60	594	&& ackno == ntohl(pcb->unacked->tcphdr->seqno) + 1) {
iva2k	0:e614f7875b60	595	pcb->snd_buf++;
iva2k	0:e614f7875b60	596	pcb->rcv_nxt = seqno + 1;
iva2k	0:e614f7875b60	597	pcb->rcv_ann_right_edge = pcb->rcv_nxt;
iva2k	0:e614f7875b60	598	pcb->lastack = ackno;
iva2k	0:e614f7875b60	599	pcb->snd_wnd = tcphdr->wnd;
iva2k	0:e614f7875b60	600	pcb->snd_wl1 = seqno - 1; /* initialise to seqno - 1 to force window update */
iva2k	0:e614f7875b60	601	pcb->state = ESTABLISHED;
iva2k	0:e614f7875b60	602
iva2k	0:e614f7875b60	603	#if TCP_CALCULATE_EFF_SEND_MSS
iva2k	0:e614f7875b60	604	pcb->mss = tcp_eff_send_mss(pcb->mss, &(pcb->remote_ip));
iva2k	0:e614f7875b60	605	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
iva2k	0:e614f7875b60	606
iva2k	0:e614f7875b60	607	/* Set ssthresh again after changing pcb->mss (already set in tcp_connect
iva2k	0:e614f7875b60	608	* but for the default value of pcb->mss) */
iva2k	0:e614f7875b60	609	pcb->ssthresh = pcb->mss * 10;
iva2k	0:e614f7875b60	610
iva2k	0:e614f7875b60	611	pcb->cwnd = ((pcb->cwnd == 1) ? (pcb->mss * 2) : pcb->mss);
iva2k	0:e614f7875b60	612	LWIP_ASSERT("pcb->snd_queuelen > 0", (pcb->snd_queuelen > 0));
iva2k	0:e614f7875b60	613	--pcb->snd_queuelen;
iva2k	0:e614f7875b60	614	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_process: SYN-SENT --queuelen %"U16_F"\n", (u16_t)pcb->snd_queuelen));
iva2k	0:e614f7875b60	615	rseg = pcb->unacked;
iva2k	0:e614f7875b60	616	pcb->unacked = rseg->next;
iva2k	0:e614f7875b60	617
iva2k	0:e614f7875b60	618	/* If there's nothing left to acknowledge, stop the retransmit
iva2k	0:e614f7875b60	619	timer, otherwise reset it to start again */
iva2k	0:e614f7875b60	620	if(pcb->unacked == NULL)
iva2k	0:e614f7875b60	621	pcb->rtime = -1;
iva2k	0:e614f7875b60	622	else {
iva2k	0:e614f7875b60	623	pcb->rtime = 0;
iva2k	0:e614f7875b60	624	pcb->nrtx = 0;
iva2k	0:e614f7875b60	625	}
iva2k	0:e614f7875b60	626
iva2k	0:e614f7875b60	627	tcp_seg_free(rseg);
iva2k	0:e614f7875b60	628
iva2k	0:e614f7875b60	629	/* Call the user specified function to call when sucessfully
iva2k	0:e614f7875b60	630	* connected. */
iva2k	0:e614f7875b60	631	TCP_EVENT_CONNECTED(pcb, ERR_OK, err);
iva2k	0:e614f7875b60	632	if (err == ERR_ABRT) {
iva2k	0:e614f7875b60	633	return ERR_ABRT;
iva2k	0:e614f7875b60	634	}
iva2k	0:e614f7875b60	635	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	636	}
iva2k	0:e614f7875b60	637	/* received ACK? possibly a half-open connection */
iva2k	0:e614f7875b60	638	else if (flags & TCP_ACK) {
iva2k	0:e614f7875b60	639	/* send a RST to bring the other side in a non-synchronized state. */
iva2k	0:e614f7875b60	640	tcp_rst(ackno, seqno + tcplen, &(iphdr->dest), &(iphdr->src),
iva2k	0:e614f7875b60	641	tcphdr->dest, tcphdr->src);
iva2k	0:e614f7875b60	642	}
iva2k	0:e614f7875b60	643	break;
iva2k	0:e614f7875b60	644	case SYN_RCVD:
iva2k	0:e614f7875b60	645	if (flags & TCP_ACK) {
iva2k	0:e614f7875b60	646	/* expected ACK number? */
iva2k	0:e614f7875b60	647	if (TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt)) {
iva2k	0:e614f7875b60	648	u16_t old_cwnd;
iva2k	0:e614f7875b60	649	pcb->state = ESTABLISHED;
iva2k	0:e614f7875b60	650	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection established %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
iva2k	0:e614f7875b60	651	#if LWIP_CALLBACK_API
iva2k	0:e614f7875b60	652	LWIP_ASSERT("pcb->accept != NULL", pcb->accept != NULL);
iva2k	0:e614f7875b60	653	#endif
iva2k	0:e614f7875b60	654	/* Call the accept function. */
iva2k	0:e614f7875b60	655	TCP_EVENT_ACCEPT(pcb, ERR_OK, err);
iva2k	0:e614f7875b60	656	if (err != ERR_OK) {
iva2k	0:e614f7875b60	657	/* If the accept function returns with an error, we abort
iva2k	0:e614f7875b60	658	* the connection. */
iva2k	0:e614f7875b60	659	/* Already aborted? */
iva2k	0:e614f7875b60	660	if (err != ERR_ABRT) {
iva2k	0:e614f7875b60	661	tcp_abort(pcb);
iva2k	0:e614f7875b60	662	}
iva2k	0:e614f7875b60	663	return ERR_ABRT;
iva2k	0:e614f7875b60	664	}
iva2k	0:e614f7875b60	665	old_cwnd = pcb->cwnd;
iva2k	0:e614f7875b60	666	/* If there was any data contained within this ACK,
iva2k	0:e614f7875b60	667	* we'd better pass it on to the application as well. */
iva2k	0:e614f7875b60	668	tcp_receive(pcb);
iva2k	0:e614f7875b60	669
iva2k	0:e614f7875b60	670	/* Prevent ACK for SYN to generate a sent event */
iva2k	0:e614f7875b60	671	if (pcb->acked != 0) {
iva2k	0:e614f7875b60	672	pcb->acked--;
iva2k	0:e614f7875b60	673	}
iva2k	0:e614f7875b60	674
iva2k	0:e614f7875b60	675	pcb->cwnd = ((old_cwnd == 1) ? (pcb->mss * 2) : pcb->mss);
iva2k	0:e614f7875b60	676
iva2k	0:e614f7875b60	677	if (recv_flags & TF_GOT_FIN) {
iva2k	0:e614f7875b60	678	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	679	pcb->state = CLOSE_WAIT;
iva2k	0:e614f7875b60	680	}
iva2k	0:e614f7875b60	681	} else {
iva2k	0:e614f7875b60	682	/* incorrect ACK number, send RST */
iva2k	0:e614f7875b60	683	tcp_rst(ackno, seqno + tcplen, &(iphdr->dest), &(iphdr->src),
iva2k	0:e614f7875b60	684	tcphdr->dest, tcphdr->src);
iva2k	0:e614f7875b60	685	}
iva2k	0:e614f7875b60	686	} else if ((flags & TCP_SYN) && (seqno == pcb->rcv_nxt - 1)) {
iva2k	0:e614f7875b60	687	/* Looks like another copy of the SYN - retransmit our SYN-ACK */
iva2k	0:e614f7875b60	688	tcp_rexmit(pcb);
iva2k	0:e614f7875b60	689	}
iva2k	0:e614f7875b60	690	break;
iva2k	0:e614f7875b60	691	case CLOSE_WAIT:
iva2k	0:e614f7875b60	692	/* FALLTHROUGH */
iva2k	0:e614f7875b60	693	case ESTABLISHED:
iva2k	0:e614f7875b60	694	tcp_receive(pcb);
iva2k	0:e614f7875b60	695	if (recv_flags & TF_GOT_FIN) { /* passive close */
iva2k	0:e614f7875b60	696	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	697	pcb->state = CLOSE_WAIT;
iva2k	0:e614f7875b60	698	}
iva2k	0:e614f7875b60	699	break;
iva2k	0:e614f7875b60	700	case FIN_WAIT_1:
iva2k	0:e614f7875b60	701	tcp_receive(pcb);
iva2k	0:e614f7875b60	702	if (recv_flags & TF_GOT_FIN) {
iva2k	0:e614f7875b60	703	if ((flags & TCP_ACK) && (ackno == pcb->snd_nxt)) {
iva2k	0:e614f7875b60	704	LWIP_DEBUGF(TCP_DEBUG,
iva2k	0:e614f7875b60	705	("TCP connection closed: FIN_WAIT_1 %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
iva2k	0:e614f7875b60	706	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	707	tcp_pcb_purge(pcb);
iva2k	0:e614f7875b60	708	TCP_RMV(&tcp_active_pcbs, pcb);
iva2k	0:e614f7875b60	709	pcb->state = TIME_WAIT;
iva2k	0:e614f7875b60	710	TCP_REG(&tcp_tw_pcbs, pcb);
iva2k	0:e614f7875b60	711	} else {
iva2k	0:e614f7875b60	712	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	713	pcb->state = CLOSING;
iva2k	0:e614f7875b60	714	}
iva2k	0:e614f7875b60	715	} else if ((flags & TCP_ACK) && (ackno == pcb->snd_nxt)) {
iva2k	0:e614f7875b60	716	pcb->state = FIN_WAIT_2;
iva2k	0:e614f7875b60	717	}
iva2k	0:e614f7875b60	718	break;
iva2k	0:e614f7875b60	719	case FIN_WAIT_2:
iva2k	0:e614f7875b60	720	tcp_receive(pcb);
iva2k	0:e614f7875b60	721	if (recv_flags & TF_GOT_FIN) {
iva2k	0:e614f7875b60	722	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: FIN_WAIT_2 %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
iva2k	0:e614f7875b60	723	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	724	tcp_pcb_purge(pcb);
iva2k	0:e614f7875b60	725	TCP_RMV(&tcp_active_pcbs, pcb);
iva2k	0:e614f7875b60	726	pcb->state = TIME_WAIT;
iva2k	0:e614f7875b60	727	TCP_REG(&tcp_tw_pcbs, pcb);
iva2k	0:e614f7875b60	728	}
iva2k	0:e614f7875b60	729	break;
iva2k	0:e614f7875b60	730	case CLOSING:
iva2k	0:e614f7875b60	731	tcp_receive(pcb);
iva2k	0:e614f7875b60	732	if (flags & TCP_ACK && ackno == pcb->snd_nxt) {
iva2k	0:e614f7875b60	733	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: CLOSING %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
iva2k	0:e614f7875b60	734	tcp_pcb_purge(pcb);
iva2k	0:e614f7875b60	735	TCP_RMV(&tcp_active_pcbs, pcb);
iva2k	0:e614f7875b60	736	pcb->state = TIME_WAIT;
iva2k	0:e614f7875b60	737	TCP_REG(&tcp_tw_pcbs, pcb);
iva2k	0:e614f7875b60	738	}
iva2k	0:e614f7875b60	739	break;
iva2k	0:e614f7875b60	740	case LAST_ACK:
iva2k	0:e614f7875b60	741	tcp_receive(pcb);
iva2k	0:e614f7875b60	742	if (flags & TCP_ACK && ackno == pcb->snd_nxt) {
iva2k	0:e614f7875b60	743	LWIP_DEBUGF(TCP_DEBUG, ("TCP connection closed: LAST_ACK %"U16_F" -> %"U16_F".\n", inseg.tcphdr->src, inseg.tcphdr->dest));
iva2k	0:e614f7875b60	744	/* bugfix #21699: don't set pcb->state to CLOSED here or we risk leaking segments */
iva2k	0:e614f7875b60	745	recv_flags \|= TF_CLOSED;
iva2k	0:e614f7875b60	746	}
iva2k	0:e614f7875b60	747	break;
iva2k	0:e614f7875b60	748	default:
iva2k	0:e614f7875b60	749	break;
iva2k	0:e614f7875b60	750	}
iva2k	0:e614f7875b60	751	return ERR_OK;
iva2k	0:e614f7875b60	752	}
iva2k	0:e614f7875b60	753
iva2k	0:e614f7875b60	754	#if TCP_QUEUE_OOSEQ
iva2k	0:e614f7875b60	755	/**
iva2k	0:e614f7875b60	756	* Insert segment into the list (segments covered with new one will be deleted)
iva2k	0:e614f7875b60	757	*
iva2k	0:e614f7875b60	758	* Called from tcp_receive()
iva2k	0:e614f7875b60	759	*/
iva2k	0:e614f7875b60	760	static void
iva2k	0:e614f7875b60	761	tcp_oos_insert_segment(struct tcp_seg cseg, struct tcp_seg next)
iva2k	0:e614f7875b60	762	{
iva2k	0:e614f7875b60	763	struct tcp_seg *old_seg;
iva2k	0:e614f7875b60	764
iva2k	0:e614f7875b60	765	if (TCPH_FLAGS(cseg->tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	766	/* received segment overlaps all following segments */
iva2k	0:e614f7875b60	767	tcp_segs_free(next);
iva2k	0:e614f7875b60	768	next = NULL;
iva2k	0:e614f7875b60	769	}
iva2k	0:e614f7875b60	770	else {
iva2k	0:e614f7875b60	771	/* delete some following segments
iva2k	0:e614f7875b60	772	oos queue may have segments with FIN flag */
iva2k	0:e614f7875b60	773	while (next &&
iva2k	0:e614f7875b60	774	TCP_SEQ_GEQ((seqno + cseg->len),
iva2k	0:e614f7875b60	775	(next->tcphdr->seqno + next->len))) {
iva2k	0:e614f7875b60	776	/* cseg with FIN already processed */
iva2k	0:e614f7875b60	777	if (TCPH_FLAGS(next->tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	778	TCPH_SET_FLAG(cseg->tcphdr, TCP_FIN);
iva2k	0:e614f7875b60	779	}
iva2k	0:e614f7875b60	780	old_seg = next;
iva2k	0:e614f7875b60	781	next = next->next;
iva2k	0:e614f7875b60	782	tcp_seg_free(old_seg);
iva2k	0:e614f7875b60	783	}
iva2k	0:e614f7875b60	784	if (next &&
iva2k	0:e614f7875b60	785	TCP_SEQ_GT(seqno + cseg->len, next->tcphdr->seqno)) {
iva2k	0:e614f7875b60	786	/* We need to trim the incoming segment. */
iva2k	0:e614f7875b60	787	cseg->len = (u16_t)(next->tcphdr->seqno - seqno);
iva2k	0:e614f7875b60	788	pbuf_realloc(cseg->p, cseg->len);
iva2k	0:e614f7875b60	789	}
iva2k	0:e614f7875b60	790	}
iva2k	0:e614f7875b60	791	cseg->next = next;
iva2k	0:e614f7875b60	792	}
iva2k	0:e614f7875b60	793	#endif /* TCP_QUEUE_OOSEQ */
iva2k	0:e614f7875b60	794
iva2k	0:e614f7875b60	795	/**
iva2k	0:e614f7875b60	796	* Called by tcp_process. Checks if the given segment is an ACK for outstanding
iva2k	0:e614f7875b60	797	* data, and if so frees the memory of the buffered data. Next, is places the
iva2k	0:e614f7875b60	798	* segment on any of the receive queues (pcb->recved or pcb->ooseq). If the segment
iva2k	0:e614f7875b60	799	* is buffered, the pbuf is referenced by pbuf_ref so that it will not be freed until
iva2k	0:e614f7875b60	800	* i it has been removed from the buffer.
iva2k	0:e614f7875b60	801	*
iva2k	0:e614f7875b60	802	* If the incoming segment constitutes an ACK for a segment that was used for RTT
iva2k	0:e614f7875b60	803	* estimation, the RTT is estimated here as well.
iva2k	0:e614f7875b60	804	*
iva2k	0:e614f7875b60	805	* Called from tcp_process().
iva2k	0:e614f7875b60	806	*/
iva2k	0:e614f7875b60	807	static void
iva2k	0:e614f7875b60	808	tcp_receive(struct tcp_pcb *pcb)
iva2k	0:e614f7875b60	809	{
iva2k	0:e614f7875b60	810	struct tcp_seg *next;
iva2k	0:e614f7875b60	811	#if TCP_QUEUE_OOSEQ
iva2k	0:e614f7875b60	812	struct tcp_seg prev, cseg;
iva2k	0:e614f7875b60	813	#endif /* TCP_QUEUE_OOSEQ */
iva2k	0:e614f7875b60	814	struct pbuf *p;
iva2k	0:e614f7875b60	815	s32_t off;
iva2k	0:e614f7875b60	816	s16_t m;
iva2k	0:e614f7875b60	817	u32_t right_wnd_edge;
iva2k	0:e614f7875b60	818	u16_t new_tot_len;
iva2k	0:e614f7875b60	819	int found_dupack = 0;
iva2k	0:e614f7875b60	820
iva2k	0:e614f7875b60	821	if (flags & TCP_ACK) {
iva2k	0:e614f7875b60	822	right_wnd_edge = pcb->snd_wnd + pcb->snd_wl2;
iva2k	0:e614f7875b60	823
iva2k	0:e614f7875b60	824	/* Update window. */
iva2k	0:e614f7875b60	825	if (TCP_SEQ_LT(pcb->snd_wl1, seqno) \|\|
iva2k	0:e614f7875b60	826	(pcb->snd_wl1 == seqno && TCP_SEQ_LT(pcb->snd_wl2, ackno)) \|\|
iva2k	0:e614f7875b60	827	(pcb->snd_wl2 == ackno && tcphdr->wnd > pcb->snd_wnd)) {
iva2k	0:e614f7875b60	828	pcb->snd_wnd = tcphdr->wnd;
iva2k	0:e614f7875b60	829	pcb->snd_wl1 = seqno;
iva2k	0:e614f7875b60	830	pcb->snd_wl2 = ackno;
iva2k	0:e614f7875b60	831	if (pcb->snd_wnd > 0 && pcb->persist_backoff > 0) {
iva2k	0:e614f7875b60	832	pcb->persist_backoff = 0;
iva2k	0:e614f7875b60	833	}
iva2k	0:e614f7875b60	834	LWIP_DEBUGF(TCP_WND_DEBUG, ("tcp_receive: window update %"U16_F"\n", pcb->snd_wnd));
iva2k	0:e614f7875b60	835	#if TCP_WND_DEBUG
iva2k	0:e614f7875b60	836	} else {
iva2k	0:e614f7875b60	837	if (pcb->snd_wnd != tcphdr->wnd) {
iva2k	0:e614f7875b60	838	LWIP_DEBUGF(TCP_WND_DEBUG,
iva2k	0:e614f7875b60	839	("tcp_receive: no window update lastack %"U32_F" ackno %"
iva2k	0:e614f7875b60	840	U32_F" wl1 %"U32_F" seqno %"U32_F" wl2 %"U32_F"\n",
iva2k	0:e614f7875b60	841	pcb->lastack, ackno, pcb->snd_wl1, seqno, pcb->snd_wl2));
iva2k	0:e614f7875b60	842	}
iva2k	0:e614f7875b60	843	#endif /* TCP_WND_DEBUG */
iva2k	0:e614f7875b60	844	}
iva2k	0:e614f7875b60	845
iva2k	0:e614f7875b60	846	/* (From Stevens TCP/IP Illustrated Vol II, p970.) Its only a
iva2k	0:e614f7875b60	847	* duplicate ack if:
iva2k	0:e614f7875b60	848	* 1) It doesn't ACK new data
iva2k	0:e614f7875b60	849	* 2) length of received packet is zero (i.e. no payload)
iva2k	0:e614f7875b60	850	* 3) the advertised window hasn't changed
iva2k	0:e614f7875b60	851	* 4) There is outstanding unacknowledged data (retransmission timer running)
iva2k	0:e614f7875b60	852	* 5) The ACK is == biggest ACK sequence number so far seen (snd_una)
iva2k	0:e614f7875b60	853	*
iva2k	0:e614f7875b60	854	* If it passes all five, should process as a dupack:
iva2k	0:e614f7875b60	855	* a) dupacks < 3: do nothing
iva2k	0:e614f7875b60	856	* b) dupacks == 3: fast retransmit
iva2k	0:e614f7875b60	857	* c) dupacks > 3: increase cwnd
iva2k	0:e614f7875b60	858	*
iva2k	0:e614f7875b60	859	* If it only passes 1-3, should reset dupack counter (and add to
iva2k	0:e614f7875b60	860	* stats, which we don't do in lwIP)
iva2k	0:e614f7875b60	861	*
iva2k	0:e614f7875b60	862	* If it only passes 1, should reset dupack counter
iva2k	0:e614f7875b60	863	*
iva2k	0:e614f7875b60	864	*/
iva2k	0:e614f7875b60	865
iva2k	0:e614f7875b60	866	/* Clause 1 */
iva2k	0:e614f7875b60	867	if (TCP_SEQ_LEQ(ackno, pcb->lastack)) {
iva2k	0:e614f7875b60	868	pcb->acked = 0;
iva2k	0:e614f7875b60	869	/* Clause 2 */
iva2k	0:e614f7875b60	870	if (tcplen == 0) {
iva2k	0:e614f7875b60	871	/* Clause 3 */
iva2k	0:e614f7875b60	872	if (pcb->snd_wl2 + pcb->snd_wnd == right_wnd_edge){
iva2k	0:e614f7875b60	873	/* Clause 4 */
iva2k	0:e614f7875b60	874	if (pcb->rtime >= 0) {
iva2k	0:e614f7875b60	875	/* Clause 5 */
iva2k	0:e614f7875b60	876	if (pcb->lastack == ackno) {
iva2k	0:e614f7875b60	877	found_dupack = 1;
iva2k	0:e614f7875b60	878	if (pcb->dupacks + 1 > pcb->dupacks)
iva2k	0:e614f7875b60	879	++pcb->dupacks;
iva2k	0:e614f7875b60	880	if (pcb->dupacks > 3) {
iva2k	0:e614f7875b60	881	/* Inflate the congestion window, but not if it means that
iva2k	0:e614f7875b60	882	the value overflows. */
iva2k	0:e614f7875b60	883	if ((u16_t)(pcb->cwnd + pcb->mss) > pcb->cwnd) {
iva2k	0:e614f7875b60	884	pcb->cwnd += pcb->mss;
iva2k	0:e614f7875b60	885	}
iva2k	0:e614f7875b60	886	} else if (pcb->dupacks == 3) {
iva2k	0:e614f7875b60	887	/* Do fast retransmit */
iva2k	0:e614f7875b60	888	tcp_rexmit_fast(pcb);
iva2k	0:e614f7875b60	889	}
iva2k	0:e614f7875b60	890	}
iva2k	0:e614f7875b60	891	}
iva2k	0:e614f7875b60	892	}
iva2k	0:e614f7875b60	893	}
iva2k	0:e614f7875b60	894	/* If Clause (1) or more is true, but not a duplicate ack, reset
iva2k	0:e614f7875b60	895	* count of consecutive duplicate acks */
iva2k	0:e614f7875b60	896	if (!found_dupack) {
iva2k	0:e614f7875b60	897	pcb->dupacks = 0;
iva2k	0:e614f7875b60	898	}
iva2k	0:e614f7875b60	899	} else if (TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt)){
iva2k	0:e614f7875b60	900	/* We come here when the ACK acknowledges new data. */
iva2k	0:e614f7875b60	901
iva2k	0:e614f7875b60	902	/* Reset the "IN Fast Retransmit" flag, since we are no longer
iva2k	0:e614f7875b60	903	in fast retransmit. Also reset the congestion window to the
iva2k	0:e614f7875b60	904	slow start threshold. */
iva2k	0:e614f7875b60	905	if (pcb->flags & TF_INFR) {
iva2k	0:e614f7875b60	906	pcb->flags &= ~TF_INFR;
iva2k	0:e614f7875b60	907	pcb->cwnd = pcb->ssthresh;
iva2k	0:e614f7875b60	908	}
iva2k	0:e614f7875b60	909
iva2k	0:e614f7875b60	910	/* Reset the number of retransmissions. */
iva2k	0:e614f7875b60	911	pcb->nrtx = 0;
iva2k	0:e614f7875b60	912
iva2k	0:e614f7875b60	913	/* Reset the retransmission time-out. */
iva2k	0:e614f7875b60	914	pcb->rto = (pcb->sa >> 3) + pcb->sv;
iva2k	0:e614f7875b60	915
iva2k	0:e614f7875b60	916	/* Update the send buffer space. Diff between the two can never exceed 64K? */
iva2k	0:e614f7875b60	917	pcb->acked = (u16_t)(ackno - pcb->lastack);
iva2k	0:e614f7875b60	918
iva2k	0:e614f7875b60	919	pcb->snd_buf += pcb->acked;
iva2k	0:e614f7875b60	920
iva2k	0:e614f7875b60	921	/* Reset the fast retransmit variables. */
iva2k	0:e614f7875b60	922	pcb->dupacks = 0;
iva2k	0:e614f7875b60	923	pcb->lastack = ackno;
iva2k	0:e614f7875b60	924
iva2k	0:e614f7875b60	925	/* Update the congestion control variables (cwnd and
iva2k	0:e614f7875b60	926	ssthresh). */
iva2k	0:e614f7875b60	927	if (pcb->state >= ESTABLISHED) {
iva2k	0:e614f7875b60	928	if (pcb->cwnd < pcb->ssthresh) {
iva2k	0:e614f7875b60	929	if ((u16_t)(pcb->cwnd + pcb->mss) > pcb->cwnd) {
iva2k	0:e614f7875b60	930	pcb->cwnd += pcb->mss;
iva2k	0:e614f7875b60	931	}
iva2k	0:e614f7875b60	932	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_receive: slow start cwnd %"U16_F"\n", pcb->cwnd));
iva2k	0:e614f7875b60	933	} else {
iva2k	0:e614f7875b60	934	u16_t new_cwnd = (pcb->cwnd + pcb->mss * pcb->mss / pcb->cwnd);
iva2k	0:e614f7875b60	935	if (new_cwnd > pcb->cwnd) {
iva2k	0:e614f7875b60	936	pcb->cwnd = new_cwnd;
iva2k	0:e614f7875b60	937	}
iva2k	0:e614f7875b60	938	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_receive: congestion avoidance cwnd %"U16_F"\n", pcb->cwnd));
iva2k	0:e614f7875b60	939	}
iva2k	0:e614f7875b60	940	}
iva2k	0:e614f7875b60	941	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: ACK for %"U32_F", unacked->seqno %"U32_F":%"U32_F"\n",
iva2k	0:e614f7875b60	942	ackno,
iva2k	0:e614f7875b60	943	pcb->unacked != NULL?
iva2k	0:e614f7875b60	944	ntohl(pcb->unacked->tcphdr->seqno): 0,
iva2k	0:e614f7875b60	945	pcb->unacked != NULL?
iva2k	0:e614f7875b60	946	ntohl(pcb->unacked->tcphdr->seqno) + TCP_TCPLEN(pcb->unacked): 0));
iva2k	0:e614f7875b60	947
iva2k	0:e614f7875b60	948	/* Remove segment from the unacknowledged list if the incoming
iva2k	0:e614f7875b60	949	ACK acknowlegdes them. */
iva2k	0:e614f7875b60	950	while (pcb->unacked != NULL &&
iva2k	0:e614f7875b60	951	TCP_SEQ_LEQ(ntohl(pcb->unacked->tcphdr->seqno) +
iva2k	0:e614f7875b60	952	TCP_TCPLEN(pcb->unacked), ackno)) {
iva2k	0:e614f7875b60	953	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %"U32_F":%"U32_F" from pcb->unacked\n",
iva2k	0:e614f7875b60	954	ntohl(pcb->unacked->tcphdr->seqno),
iva2k	0:e614f7875b60	955	ntohl(pcb->unacked->tcphdr->seqno) +
iva2k	0:e614f7875b60	956	TCP_TCPLEN(pcb->unacked)));
iva2k	0:e614f7875b60	957
iva2k	0:e614f7875b60	958	next = pcb->unacked;
iva2k	0:e614f7875b60	959	pcb->unacked = pcb->unacked->next;
iva2k	0:e614f7875b60	960
iva2k	0:e614f7875b60	961	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_receive: queuelen %"U16_F" ... ", (u16_t)pcb->snd_queuelen));
iva2k	0:e614f7875b60	962	LWIP_ASSERT("pcb->snd_queuelen >= pbuf_clen(next->p)", (pcb->snd_queuelen >= pbuf_clen(next->p)));
iva2k	0:e614f7875b60	963	/* Prevent ACK for FIN to generate a sent event */
iva2k	0:e614f7875b60	964	if ((pcb->acked != 0) && ((TCPH_FLAGS(next->tcphdr) & TCP_FIN) != 0)) {
iva2k	0:e614f7875b60	965	pcb->acked--;
iva2k	0:e614f7875b60	966	}
iva2k	0:e614f7875b60	967
iva2k	0:e614f7875b60	968	pcb->snd_queuelen -= pbuf_clen(next->p);
iva2k	0:e614f7875b60	969	tcp_seg_free(next);
iva2k	0:e614f7875b60	970
iva2k	0:e614f7875b60	971	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("%"U16_F" (after freeing unacked)\n", (u16_t)pcb->snd_queuelen));
iva2k	0:e614f7875b60	972	if (pcb->snd_queuelen != 0) {
iva2k	0:e614f7875b60	973	LWIP_ASSERT("tcp_receive: valid queue length", pcb->unacked != NULL \|\|
iva2k	0:e614f7875b60	974	pcb->unsent != NULL);
iva2k	0:e614f7875b60	975	}
iva2k	0:e614f7875b60	976	}
iva2k	0:e614f7875b60	977
iva2k	0:e614f7875b60	978	/* If there's nothing left to acknowledge, stop the retransmit
iva2k	0:e614f7875b60	979	timer, otherwise reset it to start again */
iva2k	0:e614f7875b60	980	if(pcb->unacked == NULL)
iva2k	0:e614f7875b60	981	pcb->rtime = -1;
iva2k	0:e614f7875b60	982	else
iva2k	0:e614f7875b60	983	pcb->rtime = 0;
iva2k	0:e614f7875b60	984
iva2k	0:e614f7875b60	985	pcb->polltmr = 0;
iva2k	0:e614f7875b60	986	} else {
iva2k	0:e614f7875b60	987	/* Fix bug bug #21582: out of sequence ACK, didn't really ack anything */
iva2k	0:e614f7875b60	988	pcb->acked = 0;
iva2k	0:e614f7875b60	989	}
iva2k	0:e614f7875b60	990
iva2k	0:e614f7875b60	991	/* We go through the ->unsent list to see if any of the segments
iva2k	0:e614f7875b60	992	on the list are acknowledged by the ACK. This may seem
iva2k	0:e614f7875b60	993	strange since an "unsent" segment shouldn't be acked. The
iva2k	0:e614f7875b60	994	rationale is that lwIP puts all outstanding segments on the
iva2k	0:e614f7875b60	995	->unsent list after a retransmission, so these segments may
iva2k	0:e614f7875b60	996	in fact have been sent once. */
iva2k	0:e614f7875b60	997	while (pcb->unsent != NULL &&
iva2k	0:e614f7875b60	998	TCP_SEQ_BETWEEN(ackno, ntohl(pcb->unsent->tcphdr->seqno) +
iva2k	0:e614f7875b60	999	TCP_TCPLEN(pcb->unsent), pcb->snd_nxt)) {
iva2k	0:e614f7875b60	1000	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %"U32_F":%"U32_F" from pcb->unsent\n",
iva2k	0:e614f7875b60	1001	ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) +
iva2k	0:e614f7875b60	1002	TCP_TCPLEN(pcb->unsent)));
iva2k	0:e614f7875b60	1003
iva2k	0:e614f7875b60	1004	next = pcb->unsent;
iva2k	0:e614f7875b60	1005	pcb->unsent = pcb->unsent->next;
iva2k	0:e614f7875b60	1006	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_receive: queuelen %"U16_F" ... ", (u16_t)pcb->snd_queuelen));
iva2k	0:e614f7875b60	1007	LWIP_ASSERT("pcb->snd_queuelen >= pbuf_clen(next->p)", (pcb->snd_queuelen >= pbuf_clen(next->p)));
iva2k	0:e614f7875b60	1008	/* Prevent ACK for FIN to generate a sent event */
iva2k	0:e614f7875b60	1009	if ((pcb->acked != 0) && ((TCPH_FLAGS(next->tcphdr) & TCP_FIN) != 0)) {
iva2k	0:e614f7875b60	1010	pcb->acked--;
iva2k	0:e614f7875b60	1011	}
iva2k	0:e614f7875b60	1012	pcb->snd_queuelen -= pbuf_clen(next->p);
iva2k	0:e614f7875b60	1013	tcp_seg_free(next);
iva2k	0:e614f7875b60	1014	LWIP_DEBUGF(TCP_QLEN_DEBUG, ("%"U16_F" (after freeing unsent)\n", (u16_t)pcb->snd_queuelen));
iva2k	0:e614f7875b60	1015	if (pcb->snd_queuelen != 0) {
iva2k	0:e614f7875b60	1016	LWIP_ASSERT("tcp_receive: valid queue length",
iva2k	0:e614f7875b60	1017	pcb->unacked != NULL \|\| pcb->unsent != NULL);
iva2k	0:e614f7875b60	1018	}
iva2k	0:e614f7875b60	1019	}
iva2k	0:e614f7875b60	1020	/* End of ACK for new data processing. */
iva2k	0:e614f7875b60	1021
iva2k	0:e614f7875b60	1022	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: pcb->rttest %"U32_F" rtseq %"U32_F" ackno %"U32_F"\n",
iva2k	0:e614f7875b60	1023	pcb->rttest, pcb->rtseq, ackno));
iva2k	0:e614f7875b60	1024
iva2k	0:e614f7875b60	1025	/* RTT estimation calculations. This is done by checking if the
iva2k	0:e614f7875b60	1026	incoming segment acknowledges the segment we use to take a
iva2k	0:e614f7875b60	1027	round-trip time measurement. */
iva2k	0:e614f7875b60	1028	if (pcb->rttest && TCP_SEQ_LT(pcb->rtseq, ackno)) {
iva2k	0:e614f7875b60	1029	/* diff between this shouldn't exceed 32K since this are tcp timer ticks
iva2k	0:e614f7875b60	1030	and a round-trip shouldn't be that long... */
iva2k	0:e614f7875b60	1031	m = (s16_t)(tcp_ticks - pcb->rttest);
iva2k	0:e614f7875b60	1032
iva2k	0:e614f7875b60	1033	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: experienced rtt %"U16_F" ticks (%"U16_F" msec).\n",
iva2k	0:e614f7875b60	1034	m, m * TCP_SLOW_INTERVAL));
iva2k	0:e614f7875b60	1035
iva2k	0:e614f7875b60	1036	/* This is taken directly from VJs original code in his paper */
iva2k	0:e614f7875b60	1037	m = m - (pcb->sa >> 3);
iva2k	0:e614f7875b60	1038	pcb->sa += m;
iva2k	0:e614f7875b60	1039	if (m < 0) {
iva2k	0:e614f7875b60	1040	m = -m;
iva2k	0:e614f7875b60	1041	}
iva2k	0:e614f7875b60	1042	m = m - (pcb->sv >> 2);
iva2k	0:e614f7875b60	1043	pcb->sv += m;
iva2k	0:e614f7875b60	1044	pcb->rto = (pcb->sa >> 3) + pcb->sv;
iva2k	0:e614f7875b60	1045
iva2k	0:e614f7875b60	1046	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_receive: RTO %"U16_F" (%"U16_F" milliseconds)\n",
iva2k	0:e614f7875b60	1047	pcb->rto, pcb->rto * TCP_SLOW_INTERVAL));
iva2k	0:e614f7875b60	1048
iva2k	0:e614f7875b60	1049	pcb->rttest = 0;
iva2k	0:e614f7875b60	1050	}
iva2k	0:e614f7875b60	1051	}
iva2k	0:e614f7875b60	1052
iva2k	0:e614f7875b60	1053	/* If the incoming segment contains data, we must process it
iva2k	0:e614f7875b60	1054	further. */
iva2k	0:e614f7875b60	1055	if (tcplen > 0) {
iva2k	0:e614f7875b60	1056	/* This code basically does three things:
iva2k	0:e614f7875b60	1057
iva2k	0:e614f7875b60	1058	+) If the incoming segment contains data that is the next
iva2k	0:e614f7875b60	1059	in-sequence data, this data is passed to the application. This
iva2k	0:e614f7875b60	1060	might involve trimming the first edge of the data. The rcv_nxt
iva2k	0:e614f7875b60	1061	variable and the advertised window are adjusted.
iva2k	0:e614f7875b60	1062
iva2k	0:e614f7875b60	1063	+) If the incoming segment has data that is above the next
iva2k	0:e614f7875b60	1064	sequence number expected (->rcv_nxt), the segment is placed on
iva2k	0:e614f7875b60	1065	the ->ooseq queue. This is done by finding the appropriate
iva2k	0:e614f7875b60	1066	place in the ->ooseq queue (which is ordered by sequence
iva2k	0:e614f7875b60	1067	number) and trim the segment in both ends if needed. An
iva2k	0:e614f7875b60	1068	immediate ACK is sent to indicate that we received an
iva2k	0:e614f7875b60	1069	out-of-sequence segment.
iva2k	0:e614f7875b60	1070
iva2k	0:e614f7875b60	1071	+) Finally, we check if the first segment on the ->ooseq queue
iva2k	0:e614f7875b60	1072	now is in sequence (i.e., if rcv_nxt >= ooseq->seqno). If
iva2k	0:e614f7875b60	1073	rcv_nxt > ooseq->seqno, we must trim the first edge of the
iva2k	0:e614f7875b60	1074	segment on ->ooseq before we adjust rcv_nxt. The data in the
iva2k	0:e614f7875b60	1075	segments that are now on sequence are chained onto the
iva2k	0:e614f7875b60	1076	incoming segment so that we only need to call the application
iva2k	0:e614f7875b60	1077	once.
iva2k	0:e614f7875b60	1078	*/
iva2k	0:e614f7875b60	1079
iva2k	0:e614f7875b60	1080	/* First, we check if we must trim the first edge. We have to do
iva2k	0:e614f7875b60	1081	this if the sequence number of the incoming segment is less
iva2k	0:e614f7875b60	1082	than rcv_nxt, and the sequence number plus the length of the
iva2k	0:e614f7875b60	1083	segment is larger than rcv_nxt. */
iva2k	0:e614f7875b60	1084	/* if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
iva2k	0:e614f7875b60	1085	if (TCP_SEQ_LT(pcb->rcv_nxt, seqno + tcplen)) {*/
iva2k	0:e614f7875b60	1086	if (TCP_SEQ_BETWEEN(pcb->rcv_nxt, seqno + 1, seqno + tcplen - 1)){
iva2k	0:e614f7875b60	1087	/* Trimming the first edge is done by pushing the payload
iva2k	0:e614f7875b60	1088	pointer in the pbuf downwards. This is somewhat tricky since
iva2k	0:e614f7875b60	1089	we do not want to discard the full contents of the pbuf up to
iva2k	0:e614f7875b60	1090	the new starting point of the data since we have to keep the
iva2k	0:e614f7875b60	1091	TCP header which is present in the first pbuf in the chain.
iva2k	0:e614f7875b60	1092
iva2k	0:e614f7875b60	1093	What is done is really quite a nasty hack: the first pbuf in
iva2k	0:e614f7875b60	1094	the pbuf chain is pointed to by inseg.p. Since we need to be
iva2k	0:e614f7875b60	1095	able to deallocate the whole pbuf, we cannot change this
iva2k	0:e614f7875b60	1096	inseg.p pointer to point to any of the later pbufs in the
iva2k	0:e614f7875b60	1097	chain. Instead, we point the ->payload pointer in the first
iva2k	0:e614f7875b60	1098	pbuf to data in one of the later pbufs. We also set the
iva2k	0:e614f7875b60	1099	inseg.data pointer to point to the right place. This way, the
iva2k	0:e614f7875b60	1100	->p pointer will still point to the first pbuf, but the
iva2k	0:e614f7875b60	1101	->p->payload pointer will point to data in another pbuf.
iva2k	0:e614f7875b60	1102
iva2k	0:e614f7875b60	1103	After we are done with adjusting the pbuf pointers we must
iva2k	0:e614f7875b60	1104	adjust the ->data pointer in the seg and the segment
iva2k	0:e614f7875b60	1105	length.*/
iva2k	0:e614f7875b60	1106
iva2k	0:e614f7875b60	1107	off = pcb->rcv_nxt - seqno;
iva2k	0:e614f7875b60	1108	p = inseg.p;
iva2k	0:e614f7875b60	1109	LWIP_ASSERT("inseg.p != NULL", inseg.p);
iva2k	0:e614f7875b60	1110	LWIP_ASSERT("insane offset!", (off < 0x7fff));
iva2k	0:e614f7875b60	1111	if (inseg.p->len < off) {
iva2k	0:e614f7875b60	1112	LWIP_ASSERT("pbuf too short!", (((s32_t)inseg.p->tot_len) >= off));
iva2k	0:e614f7875b60	1113	new_tot_len = (u16_t)(inseg.p->tot_len - off);
iva2k	0:e614f7875b60	1114	while (p->len < off) {
iva2k	0:e614f7875b60	1115	off -= p->len;
iva2k	0:e614f7875b60	1116	/* KJM following line changed (with addition of new_tot_len var)
iva2k	0:e614f7875b60	1117	to fix bug #9076
iva2k	0:e614f7875b60	1118	inseg.p->tot_len -= p->len; */
iva2k	0:e614f7875b60	1119	p->tot_len = new_tot_len;
iva2k	0:e614f7875b60	1120	p->len = 0;
iva2k	0:e614f7875b60	1121	p = p->next;
iva2k	0:e614f7875b60	1122	}
iva2k	0:e614f7875b60	1123	if(pbuf_header(p, (s16_t)-off)) {
iva2k	0:e614f7875b60	1124	/* Do we need to cope with this failing? Assert for now */
iva2k	0:e614f7875b60	1125	LWIP_ASSERT("pbuf_header failed", 0);
iva2k	0:e614f7875b60	1126	}
iva2k	0:e614f7875b60	1127	} else {
iva2k	0:e614f7875b60	1128	if(pbuf_header(inseg.p, (s16_t)-off)) {
iva2k	0:e614f7875b60	1129	/* Do we need to cope with this failing? Assert for now */
iva2k	0:e614f7875b60	1130	LWIP_ASSERT("pbuf_header failed", 0);
iva2k	0:e614f7875b60	1131	}
iva2k	0:e614f7875b60	1132	}
iva2k	0:e614f7875b60	1133	/* KJM following line changed to use p->payload rather than inseg->p->payload
iva2k	0:e614f7875b60	1134	to fix bug #9076 */
iva2k	0:e614f7875b60	1135	inseg.dataptr = p->payload;
iva2k	0:e614f7875b60	1136	inseg.len -= (u16_t)(pcb->rcv_nxt - seqno);
iva2k	0:e614f7875b60	1137	inseg.tcphdr->seqno = seqno = pcb->rcv_nxt;
iva2k	0:e614f7875b60	1138	}
iva2k	0:e614f7875b60	1139	else {
iva2k	0:e614f7875b60	1140	if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
iva2k	0:e614f7875b60	1141	/* the whole segment is < rcv_nxt */
iva2k	0:e614f7875b60	1142	/* must be a duplicate of a packet that has already been correctly handled */
iva2k	0:e614f7875b60	1143
iva2k	0:e614f7875b60	1144	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: duplicate seqno %"U32_F"\n", seqno));
iva2k	0:e614f7875b60	1145	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	1146	}
iva2k	0:e614f7875b60	1147	}
iva2k	0:e614f7875b60	1148
iva2k	0:e614f7875b60	1149	/* The sequence number must be within the window (above rcv_nxt
iva2k	0:e614f7875b60	1150	and below rcv_nxt + rcv_wnd) in order to be further
iva2k	0:e614f7875b60	1151	processed. */
iva2k	0:e614f7875b60	1152	if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt,
iva2k	0:e614f7875b60	1153	pcb->rcv_nxt + pcb->rcv_wnd - 1)){
iva2k	0:e614f7875b60	1154	if (pcb->rcv_nxt == seqno) {
iva2k	0:e614f7875b60	1155	/* The incoming segment is the next in sequence. We check if
iva2k	0:e614f7875b60	1156	we have to trim the end of the segment and update rcv_nxt
iva2k	0:e614f7875b60	1157	and pass the data to the application. */
iva2k	0:e614f7875b60	1158	tcplen = TCP_TCPLEN(&inseg);
iva2k	0:e614f7875b60	1159
iva2k	0:e614f7875b60	1160	if (tcplen > pcb->rcv_wnd) {
iva2k	0:e614f7875b60	1161	LWIP_DEBUGF(TCP_INPUT_DEBUG,
iva2k	0:e614f7875b60	1162	("tcp_receive: other end overran receive window"
iva2k	0:e614f7875b60	1163	"seqno %"U32_F" len %"U16_F" right edge %"U32_F"\n",
iva2k	0:e614f7875b60	1164	seqno, tcplen, pcb->rcv_nxt + pcb->rcv_wnd));
iva2k	0:e614f7875b60	1165	if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	1166	/* Must remove the FIN from the header as we're trimming
iva2k	0:e614f7875b60	1167	* that byte of sequence-space from the packet */
iva2k	0:e614f7875b60	1168	TCPH_FLAGS_SET(inseg.tcphdr, TCPH_FLAGS(inseg.tcphdr) &~ TCP_FIN);
iva2k	0:e614f7875b60	1169	}
iva2k	0:e614f7875b60	1170	/* Adjust length of segment to fit in the window. */
iva2k	0:e614f7875b60	1171	inseg.len = pcb->rcv_wnd;
iva2k	0:e614f7875b60	1172	if (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) {
iva2k	0:e614f7875b60	1173	inseg.len -= 1;
iva2k	0:e614f7875b60	1174	}
iva2k	0:e614f7875b60	1175	pbuf_realloc(inseg.p, inseg.len);
iva2k	0:e614f7875b60	1176	tcplen = TCP_TCPLEN(&inseg);
iva2k	0:e614f7875b60	1177	LWIP_ASSERT("tcp_receive: segment not trimmed correctly to rcv_wnd\n",
iva2k	0:e614f7875b60	1178	(seqno + tcplen) == (pcb->rcv_nxt + pcb->rcv_wnd));
iva2k	0:e614f7875b60	1179	}
iva2k	0:e614f7875b60	1180	#if TCP_QUEUE_OOSEQ
iva2k	0:e614f7875b60	1181	/* Received in-sequence data, adjust ooseq data if:
iva2k	0:e614f7875b60	1182	- FIN has been received or
iva2k	0:e614f7875b60	1183	- inseq overlaps with ooseq */
iva2k	0:e614f7875b60	1184	if (pcb->ooseq != NULL) {
iva2k	0:e614f7875b60	1185	if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	1186	LWIP_DEBUGF(TCP_INPUT_DEBUG,
iva2k	0:e614f7875b60	1187	("tcp_receive: received in-order FIN, binning ooseq queue\n"));
iva2k	0:e614f7875b60	1188	/* Received in-order FIN means anything that was received
iva2k	0:e614f7875b60	1189	* out of order must now have been received in-order, so
iva2k	0:e614f7875b60	1190	* bin the ooseq queue */
iva2k	0:e614f7875b60	1191	while (pcb->ooseq != NULL) {
iva2k	0:e614f7875b60	1192	struct tcp_seg *old_ooseq = pcb->ooseq;
iva2k	0:e614f7875b60	1193	pcb->ooseq = pcb->ooseq->next;
iva2k	0:e614f7875b60	1194	tcp_seg_free(old_ooseq);
iva2k	0:e614f7875b60	1195	}
iva2k	0:e614f7875b60	1196	}
iva2k	0:e614f7875b60	1197	else {
iva2k	0:e614f7875b60	1198	next = pcb->ooseq;
iva2k	0:e614f7875b60	1199	/* Remove all segments on ooseq that are covered by inseg already.
iva2k	0:e614f7875b60	1200	* FIN is copied from ooseq to inseg if present. */
iva2k	0:e614f7875b60	1201	while (next &&
iva2k	0:e614f7875b60	1202	TCP_SEQ_GEQ(seqno + tcplen,
iva2k	0:e614f7875b60	1203	next->tcphdr->seqno + next->len)) {
iva2k	0:e614f7875b60	1204	/* inseg cannot have FIN here (already processed above) */
iva2k	0:e614f7875b60	1205	if (TCPH_FLAGS(next->tcphdr) & TCP_FIN &&
iva2k	0:e614f7875b60	1206	(TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) == 0) {
iva2k	0:e614f7875b60	1207	TCPH_SET_FLAG(inseg.tcphdr, TCP_FIN);
iva2k	0:e614f7875b60	1208	tcplen = TCP_TCPLEN(&inseg);
iva2k	0:e614f7875b60	1209	}
iva2k	0:e614f7875b60	1210	prev = next;
iva2k	0:e614f7875b60	1211	next = next->next;
iva2k	0:e614f7875b60	1212	tcp_seg_free(prev);
iva2k	0:e614f7875b60	1213	}
iva2k	0:e614f7875b60	1214	/* Now trim right side of inseg if it overlaps with the first
iva2k	0:e614f7875b60	1215	* segment on ooseq */
iva2k	0:e614f7875b60	1216	if (next &&
iva2k	0:e614f7875b60	1217	TCP_SEQ_GT(seqno + tcplen,
iva2k	0:e614f7875b60	1218	next->tcphdr->seqno)) {
iva2k	0:e614f7875b60	1219	/* inseg cannot have FIN here (already processed above) */
iva2k	0:e614f7875b60	1220	inseg.len = (u16_t)(next->tcphdr->seqno - seqno);
iva2k	0:e614f7875b60	1221	if (TCPH_FLAGS(inseg.tcphdr) & TCP_SYN) {
iva2k	0:e614f7875b60	1222	inseg.len -= 1;
iva2k	0:e614f7875b60	1223	}
iva2k	0:e614f7875b60	1224	pbuf_realloc(inseg.p, inseg.len);
iva2k	0:e614f7875b60	1225	tcplen = TCP_TCPLEN(&inseg);
iva2k	0:e614f7875b60	1226	LWIP_ASSERT("tcp_receive: segment not trimmed correctly to ooseq queue\n",
iva2k	0:e614f7875b60	1227	(seqno + tcplen) == next->tcphdr->seqno);
iva2k	0:e614f7875b60	1228	}
iva2k	0:e614f7875b60	1229	pcb->ooseq = next;
iva2k	0:e614f7875b60	1230	}
iva2k	0:e614f7875b60	1231	}
iva2k	0:e614f7875b60	1232	#endif /* TCP_QUEUE_OOSEQ */
iva2k	0:e614f7875b60	1233
iva2k	0:e614f7875b60	1234	pcb->rcv_nxt = seqno + tcplen;
iva2k	0:e614f7875b60	1235
iva2k	0:e614f7875b60	1236	/* Update the receiver's (our) window. */
iva2k	0:e614f7875b60	1237	LWIP_ASSERT("tcp_receive: tcplen > rcv_wnd\n", pcb->rcv_wnd >= tcplen);
iva2k	0:e614f7875b60	1238	pcb->rcv_wnd -= tcplen;
iva2k	0:e614f7875b60	1239
iva2k	0:e614f7875b60	1240	tcp_update_rcv_ann_wnd(pcb);
iva2k	0:e614f7875b60	1241
iva2k	0:e614f7875b60	1242	/* If there is data in the segment, we make preparations to
iva2k	0:e614f7875b60	1243	pass this up to the application. The ->recv_data variable
iva2k	0:e614f7875b60	1244	is used for holding the pbuf that goes to the
iva2k	0:e614f7875b60	1245	application. The code for reassembling out-of-sequence data
iva2k	0:e614f7875b60	1246	chains its data on this pbuf as well.
iva2k	0:e614f7875b60	1247
iva2k	0:e614f7875b60	1248	If the segment was a FIN, we set the TF_GOT_FIN flag that will
iva2k	0:e614f7875b60	1249	be used to indicate to the application that the remote side has
iva2k	0:e614f7875b60	1250	closed its end of the connection. */
iva2k	0:e614f7875b60	1251	if (inseg.p->tot_len > 0) {
iva2k	0:e614f7875b60	1252	recv_data = inseg.p;
iva2k	0:e614f7875b60	1253	/* Since this pbuf now is the responsibility of the
iva2k	0:e614f7875b60	1254	application, we delete our reference to it so that we won't
iva2k	0:e614f7875b60	1255	(mistakingly) deallocate it. */
iva2k	0:e614f7875b60	1256	inseg.p = NULL;
iva2k	0:e614f7875b60	1257	}
iva2k	0:e614f7875b60	1258	if (TCPH_FLAGS(inseg.tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	1259	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: received FIN.\n"));
iva2k	0:e614f7875b60	1260	recv_flags \|= TF_GOT_FIN;
iva2k	0:e614f7875b60	1261	}
iva2k	0:e614f7875b60	1262
iva2k	0:e614f7875b60	1263	#if TCP_QUEUE_OOSEQ
iva2k	0:e614f7875b60	1264	/* We now check if we have segments on the ->ooseq queue that
iva2k	0:e614f7875b60	1265	are now in sequence. */
iva2k	0:e614f7875b60	1266	while (pcb->ooseq != NULL &&
iva2k	0:e614f7875b60	1267	pcb->ooseq->tcphdr->seqno == pcb->rcv_nxt) {
iva2k	0:e614f7875b60	1268
iva2k	0:e614f7875b60	1269	cseg = pcb->ooseq;
iva2k	0:e614f7875b60	1270	seqno = pcb->ooseq->tcphdr->seqno;
iva2k	0:e614f7875b60	1271
iva2k	0:e614f7875b60	1272	pcb->rcv_nxt += TCP_TCPLEN(cseg);
iva2k	0:e614f7875b60	1273	LWIP_ASSERT("tcp_receive: ooseq tcplen > rcv_wnd\n",
iva2k	0:e614f7875b60	1274	pcb->rcv_wnd >= TCP_TCPLEN(cseg));
iva2k	0:e614f7875b60	1275	pcb->rcv_wnd -= TCP_TCPLEN(cseg);
iva2k	0:e614f7875b60	1276
iva2k	0:e614f7875b60	1277	tcp_update_rcv_ann_wnd(pcb);
iva2k	0:e614f7875b60	1278
iva2k	0:e614f7875b60	1279	if (cseg->p->tot_len > 0) {
iva2k	0:e614f7875b60	1280	/* Chain this pbuf onto the pbuf that we will pass to
iva2k	0:e614f7875b60	1281	the application. */
iva2k	0:e614f7875b60	1282	if (recv_data) {
iva2k	0:e614f7875b60	1283	pbuf_cat(recv_data, cseg->p);
iva2k	0:e614f7875b60	1284	} else {
iva2k	0:e614f7875b60	1285	recv_data = cseg->p;
iva2k	0:e614f7875b60	1286	}
iva2k	0:e614f7875b60	1287	cseg->p = NULL;
iva2k	0:e614f7875b60	1288	}
iva2k	0:e614f7875b60	1289	if (TCPH_FLAGS(cseg->tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	1290	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: dequeued FIN.\n"));
iva2k	0:e614f7875b60	1291	recv_flags \|= TF_GOT_FIN;
iva2k	0:e614f7875b60	1292	if (pcb->state == ESTABLISHED) { /* force passive close or we can move to active close */
iva2k	0:e614f7875b60	1293	pcb->state = CLOSE_WAIT;
iva2k	0:e614f7875b60	1294	}
iva2k	0:e614f7875b60	1295	}
iva2k	0:e614f7875b60	1296
iva2k	0:e614f7875b60	1297	pcb->ooseq = cseg->next;
iva2k	0:e614f7875b60	1298	tcp_seg_free(cseg);
iva2k	0:e614f7875b60	1299	}
iva2k	0:e614f7875b60	1300	#endif /* TCP_QUEUE_OOSEQ */
iva2k	0:e614f7875b60	1301
iva2k	0:e614f7875b60	1302
iva2k	0:e614f7875b60	1303	/* Acknowledge the segment(s). */
iva2k	0:e614f7875b60	1304	tcp_ack(pcb);
iva2k	0:e614f7875b60	1305
iva2k	0:e614f7875b60	1306	} else {
iva2k	0:e614f7875b60	1307	/* We get here if the incoming segment is out-of-sequence. */
iva2k	0:e614f7875b60	1308	tcp_send_empty_ack(pcb);
iva2k	0:e614f7875b60	1309	#if TCP_QUEUE_OOSEQ
iva2k	0:e614f7875b60	1310	/* We queue the segment on the ->ooseq queue. */
iva2k	0:e614f7875b60	1311	if (pcb->ooseq == NULL) {
iva2k	0:e614f7875b60	1312	pcb->ooseq = tcp_seg_copy(&inseg);
iva2k	0:e614f7875b60	1313	} else {
iva2k	0:e614f7875b60	1314	/* If the queue is not empty, we walk through the queue and
iva2k	0:e614f7875b60	1315	try to find a place where the sequence number of the
iva2k	0:e614f7875b60	1316	incoming segment is between the sequence numbers of the
iva2k	0:e614f7875b60	1317	previous and the next segment on the ->ooseq queue. That is
iva2k	0:e614f7875b60	1318	the place where we put the incoming segment. If needed, we
iva2k	0:e614f7875b60	1319	trim the second edges of the previous and the incoming
iva2k	0:e614f7875b60	1320	segment so that it will fit into the sequence.
iva2k	0:e614f7875b60	1321
iva2k	0:e614f7875b60	1322	If the incoming segment has the same sequence number as a
iva2k	0:e614f7875b60	1323	segment on the ->ooseq queue, we discard the segment that
iva2k	0:e614f7875b60	1324	contains less data. */
iva2k	0:e614f7875b60	1325
iva2k	0:e614f7875b60	1326	prev = NULL;
iva2k	0:e614f7875b60	1327	for(next = pcb->ooseq; next != NULL; next = next->next) {
iva2k	0:e614f7875b60	1328	if (seqno == next->tcphdr->seqno) {
iva2k	0:e614f7875b60	1329	/* The sequence number of the incoming segment is the
iva2k	0:e614f7875b60	1330	same as the sequence number of the segment on
iva2k	0:e614f7875b60	1331	->ooseq. We check the lengths to see which one to
iva2k	0:e614f7875b60	1332	discard. */
iva2k	0:e614f7875b60	1333	if (inseg.len > next->len) {
iva2k	0:e614f7875b60	1334	/* The incoming segment is larger than the old
iva2k	0:e614f7875b60	1335	segment. We replace some segments with the new
iva2k	0:e614f7875b60	1336	one. */
iva2k	0:e614f7875b60	1337	cseg = tcp_seg_copy(&inseg);
iva2k	0:e614f7875b60	1338	if (cseg != NULL) {
iva2k	0:e614f7875b60	1339	if (prev != NULL) {
iva2k	0:e614f7875b60	1340	prev->next = cseg;
iva2k	0:e614f7875b60	1341	} else {
iva2k	0:e614f7875b60	1342	pcb->ooseq = cseg;
iva2k	0:e614f7875b60	1343	}
iva2k	0:e614f7875b60	1344	tcp_oos_insert_segment(cseg, next);
iva2k	0:e614f7875b60	1345	}
iva2k	0:e614f7875b60	1346	break;
iva2k	0:e614f7875b60	1347	} else {
iva2k	0:e614f7875b60	1348	/* Either the lenghts are the same or the incoming
iva2k	0:e614f7875b60	1349	segment was smaller than the old one; in either
iva2k	0:e614f7875b60	1350	case, we ditch the incoming segment. */
iva2k	0:e614f7875b60	1351	break;
iva2k	0:e614f7875b60	1352	}
iva2k	0:e614f7875b60	1353	} else {
iva2k	0:e614f7875b60	1354	if (prev == NULL) {
iva2k	0:e614f7875b60	1355	if (TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {
iva2k	0:e614f7875b60	1356	/* The sequence number of the incoming segment is lower
iva2k	0:e614f7875b60	1357	than the sequence number of the first segment on the
iva2k	0:e614f7875b60	1358	queue. We put the incoming segment first on the
iva2k	0:e614f7875b60	1359	queue. */
iva2k	0:e614f7875b60	1360	cseg = tcp_seg_copy(&inseg);
iva2k	0:e614f7875b60	1361	if (cseg != NULL) {
iva2k	0:e614f7875b60	1362	pcb->ooseq = cseg;
iva2k	0:e614f7875b60	1363	tcp_oos_insert_segment(cseg, next);
iva2k	0:e614f7875b60	1364	}
iva2k	0:e614f7875b60	1365	break;
iva2k	0:e614f7875b60	1366	}
iva2k	0:e614f7875b60	1367	} else {
iva2k	0:e614f7875b60	1368	/*if (TCP_SEQ_LT(prev->tcphdr->seqno, seqno) &&
iva2k	0:e614f7875b60	1369	TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {*/
iva2k	0:e614f7875b60	1370	if (TCP_SEQ_BETWEEN(seqno, prev->tcphdr->seqno+1, next->tcphdr->seqno-1)) {
iva2k	0:e614f7875b60	1371	/* The sequence number of the incoming segment is in
iva2k	0:e614f7875b60	1372	between the sequence numbers of the previous and
iva2k	0:e614f7875b60	1373	the next segment on ->ooseq. We trim trim the previous
iva2k	0:e614f7875b60	1374	segment, delete next segments that included in received segment
iva2k	0:e614f7875b60	1375	and trim received, if needed. */
iva2k	0:e614f7875b60	1376	cseg = tcp_seg_copy(&inseg);
iva2k	0:e614f7875b60	1377	if (cseg != NULL) {
iva2k	0:e614f7875b60	1378	if (TCP_SEQ_GT(prev->tcphdr->seqno + prev->len, seqno)) {
iva2k	0:e614f7875b60	1379	/* We need to trim the prev segment. */
iva2k	0:e614f7875b60	1380	prev->len = (u16_t)(seqno - prev->tcphdr->seqno);
iva2k	0:e614f7875b60	1381	pbuf_realloc(prev->p, prev->len);
iva2k	0:e614f7875b60	1382	}
iva2k	0:e614f7875b60	1383	prev->next = cseg;
iva2k	0:e614f7875b60	1384	tcp_oos_insert_segment(cseg, next);
iva2k	0:e614f7875b60	1385	}
iva2k	0:e614f7875b60	1386	break;
iva2k	0:e614f7875b60	1387	}
iva2k	0:e614f7875b60	1388	}
iva2k	0:e614f7875b60	1389	/* If the "next" segment is the last segment on the
iva2k	0:e614f7875b60	1390	ooseq queue, we add the incoming segment to the end
iva2k	0:e614f7875b60	1391	of the list. */
iva2k	0:e614f7875b60	1392	if (next->next == NULL &&
iva2k	0:e614f7875b60	1393	TCP_SEQ_GT(seqno, next->tcphdr->seqno)) {
iva2k	0:e614f7875b60	1394	if (TCPH_FLAGS(next->tcphdr) & TCP_FIN) {
iva2k	0:e614f7875b60	1395	/* segment "next" already contains all data */
iva2k	0:e614f7875b60	1396	break;
iva2k	0:e614f7875b60	1397	}
iva2k	0:e614f7875b60	1398	next->next = tcp_seg_copy(&inseg);
iva2k	0:e614f7875b60	1399	if (next->next != NULL) {
iva2k	0:e614f7875b60	1400	if (TCP_SEQ_GT(next->tcphdr->seqno + next->len, seqno)) {
iva2k	0:e614f7875b60	1401	/* We need to trim the last segment. */
iva2k	0:e614f7875b60	1402	next->len = (u16_t)(seqno - next->tcphdr->seqno);
iva2k	0:e614f7875b60	1403	pbuf_realloc(next->p, next->len);
iva2k	0:e614f7875b60	1404	}
iva2k	0:e614f7875b60	1405	}
iva2k	0:e614f7875b60	1406	break;
iva2k	0:e614f7875b60	1407	}
iva2k	0:e614f7875b60	1408	}
iva2k	0:e614f7875b60	1409	prev = next;
iva2k	0:e614f7875b60	1410	}
iva2k	0:e614f7875b60	1411	}
iva2k	0:e614f7875b60	1412	#endif /* TCP_QUEUE_OOSEQ */
iva2k	0:e614f7875b60	1413
iva2k	0:e614f7875b60	1414	}
iva2k	0:e614f7875b60	1415	} else {
iva2k	0:e614f7875b60	1416	/* The incoming segment is not withing the window. */
iva2k	0:e614f7875b60	1417	tcp_send_empty_ack(pcb);
iva2k	0:e614f7875b60	1418	}
iva2k	0:e614f7875b60	1419	} else {
iva2k	0:e614f7875b60	1420	/* Segments with length 0 is taken care of here. Segments that
iva2k	0:e614f7875b60	1421	fall out of the window are ACKed. */
iva2k	0:e614f7875b60	1422	/*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) \|\|
iva2k	0:e614f7875b60	1423	TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {*/
iva2k	0:e614f7875b60	1424	if(!TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt + pcb->rcv_wnd-1)){
iva2k	0:e614f7875b60	1425	tcp_ack_now(pcb);
iva2k	0:e614f7875b60	1426	}
iva2k	0:e614f7875b60	1427	}
iva2k	0:e614f7875b60	1428	}
iva2k	0:e614f7875b60	1429
iva2k	0:e614f7875b60	1430	/**
iva2k	0:e614f7875b60	1431	* Parses the options contained in the incoming segment.
iva2k	0:e614f7875b60	1432	*
iva2k	0:e614f7875b60	1433	* Called from tcp_listen_input() and tcp_process().
iva2k	0:e614f7875b60	1434	* Currently, only the MSS option is supported!
iva2k	0:e614f7875b60	1435	*
iva2k	0:e614f7875b60	1436	* @param pcb the tcp_pcb for which a segment arrived
iva2k	0:e614f7875b60	1437	*/
iva2k	0:e614f7875b60	1438	static void
iva2k	0:e614f7875b60	1439	tcp_parseopt(struct tcp_pcb *pcb)
iva2k	0:e614f7875b60	1440	{
iva2k	0:e614f7875b60	1441	u16_t c, max_c;
iva2k	0:e614f7875b60	1442	u16_t mss;
iva2k	0:e614f7875b60	1443	u8_t *opts, opt;
iva2k	0:e614f7875b60	1444	#if LWIP_TCP_TIMESTAMPS
iva2k	0:e614f7875b60	1445	u32_t tsval;
iva2k	0:e614f7875b60	1446	#endif
iva2k	0:e614f7875b60	1447
iva2k	0:e614f7875b60	1448	opts = (u8_t *)tcphdr + TCP_HLEN;
iva2k	0:e614f7875b60	1449
iva2k	0:e614f7875b60	1450	/* Parse the TCP MSS option, if present. */
iva2k	0:e614f7875b60	1451	if(TCPH_HDRLEN(tcphdr) > 0x5) {
iva2k	0:e614f7875b60	1452	max_c = (TCPH_HDRLEN(tcphdr) - 5) << 2;
iva2k	0:e614f7875b60	1453	for (c = 0; c < max_c; ) {
iva2k	0:e614f7875b60	1454	opt = opts[c];
iva2k	0:e614f7875b60	1455	switch (opt) {
iva2k	0:e614f7875b60	1456	case 0x00:
iva2k	0:e614f7875b60	1457	/* End of options. */
iva2k	0:e614f7875b60	1458	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: EOL\n"));
iva2k	0:e614f7875b60	1459	return;
iva2k	0:e614f7875b60	1460	case 0x01:
iva2k	0:e614f7875b60	1461	/* NOP option. */
iva2k	0:e614f7875b60	1462	++c;
iva2k	0:e614f7875b60	1463	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: NOP\n"));
iva2k	0:e614f7875b60	1464	break;
iva2k	0:e614f7875b60	1465	case 0x02:
iva2k	0:e614f7875b60	1466	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: MSS\n"));
iva2k	0:e614f7875b60	1467	if (opts[c + 1] != 0x04 \|\| c + 0x04 > max_c) {
iva2k	0:e614f7875b60	1468	/* Bad length */
iva2k	0:e614f7875b60	1469	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
iva2k	0:e614f7875b60	1470	return;
iva2k	0:e614f7875b60	1471	}
iva2k	0:e614f7875b60	1472	/* An MSS option with the right option length. */
iva2k	0:e614f7875b60	1473	mss = (opts[c + 2] << 8) \| opts[c + 3];
iva2k	0:e614f7875b60	1474	/* Limit the mss to the configured TCP_MSS and prevent division by zero */
iva2k	0:e614f7875b60	1475	pcb->mss = ((mss > TCP_MSS) \|\| (mss == 0)) ? TCP_MSS : mss;
iva2k	0:e614f7875b60	1476	/* Advance to next option */
iva2k	0:e614f7875b60	1477	c += 0x04;
iva2k	0:e614f7875b60	1478	break;
iva2k	0:e614f7875b60	1479	#if LWIP_TCP_TIMESTAMPS
iva2k	0:e614f7875b60	1480	case 0x08:
iva2k	0:e614f7875b60	1481	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: TS\n"));
iva2k	0:e614f7875b60	1482	if (opts[c + 1] != 0x0A \|\| c + 0x0A > max_c) {
iva2k	0:e614f7875b60	1483	/* Bad length */
iva2k	0:e614f7875b60	1484	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
iva2k	0:e614f7875b60	1485	return;
iva2k	0:e614f7875b60	1486	}
iva2k	0:e614f7875b60	1487	/* TCP timestamp option with valid length */
iva2k	0:e614f7875b60	1488	tsval = (opts[c+2]) \| (opts[c+3] << 8) \|
iva2k	0:e614f7875b60	1489	(opts[c+4] << 16) \| (opts[c+5] << 24);
iva2k	0:e614f7875b60	1490	if (flags & TCP_SYN) {
iva2k	0:e614f7875b60	1491	pcb->ts_recent = ntohl(tsval);
iva2k	0:e614f7875b60	1492	pcb->flags \|= TF_TIMESTAMP;
iva2k	0:e614f7875b60	1493	} else if (TCP_SEQ_BETWEEN(pcb->ts_lastacksent, seqno, seqno+tcplen)) {
iva2k	0:e614f7875b60	1494	pcb->ts_recent = ntohl(tsval);
iva2k	0:e614f7875b60	1495	}
iva2k	0:e614f7875b60	1496	/* Advance to next option */
iva2k	0:e614f7875b60	1497	c += 0x0A;
iva2k	0:e614f7875b60	1498	break;
iva2k	0:e614f7875b60	1499	#endif
iva2k	0:e614f7875b60	1500	default:
iva2k	0:e614f7875b60	1501	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: other\n"));
iva2k	0:e614f7875b60	1502	if (opts[c + 1] == 0) {
iva2k	0:e614f7875b60	1503	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_parseopt: bad length\n"));
iva2k	0:e614f7875b60	1504	/* If the length field is zero, the options are malformed
iva2k	0:e614f7875b60	1505	and we don't process them further. */
iva2k	0:e614f7875b60	1506	return;
iva2k	0:e614f7875b60	1507	}
iva2k	0:e614f7875b60	1508	/* All other options have a length field, so that we easily
iva2k	0:e614f7875b60	1509	can skip past them. */
iva2k	0:e614f7875b60	1510	c += opts[c + 1];
iva2k	0:e614f7875b60	1511	}
iva2k	0:e614f7875b60	1512	}
iva2k	0:e614f7875b60	1513	}
iva2k	0:e614f7875b60	1514	}
iva2k	0:e614f7875b60	1515
iva2k	0:e614f7875b60	1516	#endif /* LWIP_TCP */

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	12 Jun 2010
Imports:	78
Forks:	0
Commits:	2
Dependents:	0
Dependencies:	1
Followers:	1

lwip/core/tcp_in.c@1:3ee499525aa5, 2010-06-14 (annotated)

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