UDPtest - Some quick code to use UDP-only (no TCP) with mBe…

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Some quick code to use UDP-only (no TCP) with mBed. Echos received packets and sends packets when a button is pressed

Core/lwIP/core/tcp.c@0:a548a085de55, 2010-03-14 (annotated)

Committer:: pehrhovey
Date:: Sun Mar 14 00:54:12 2010 +0000
Revision:: 0:a548a085de55

Who changed what in which revision?

User	Revision	Line number	New contents of line
pehrhovey	0:a548a085de55	1	/**
pehrhovey	0:a548a085de55	2	* @file
pehrhovey	0:a548a085de55	3	* Transmission Control Protocol for IP
pehrhovey	0:a548a085de55	4	*
pehrhovey	0:a548a085de55	5	* This file contains common functions for the TCP implementation, such as functinos
pehrhovey	0:a548a085de55	6	* for manipulating the data structures and the TCP timer functions. TCP functions
pehrhovey	0:a548a085de55	7	* related to input and output is found in tcp_in.c and tcp_out.c respectively.
pehrhovey	0:a548a085de55	8	*
pehrhovey	0:a548a085de55	9	*/
pehrhovey	0:a548a085de55	10
pehrhovey	0:a548a085de55	11	/*
pehrhovey	0:a548a085de55	12	* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
pehrhovey	0:a548a085de55	13	* All rights reserved.
pehrhovey	0:a548a085de55	14	*
pehrhovey	0:a548a085de55	15	* Redistribution and use in source and binary forms, with or without modification,
pehrhovey	0:a548a085de55	16	* are permitted provided that the following conditions are met:
pehrhovey	0:a548a085de55	17	*
pehrhovey	0:a548a085de55	18	* 1. Redistributions of source code must retain the above copyright notice,
pehrhovey	0:a548a085de55	19	* this list of conditions and the following disclaimer.
pehrhovey	0:a548a085de55	20	* 2. Redistributions in binary form must reproduce the above copyright notice,
pehrhovey	0:a548a085de55	21	* this list of conditions and the following disclaimer in the documentation
pehrhovey	0:a548a085de55	22	* and/or other materials provided with the distribution.
pehrhovey	0:a548a085de55	23	* 3. The name of the author may not be used to endorse or promote products
pehrhovey	0:a548a085de55	24	* derived from this software without specific prior written permission.
pehrhovey	0:a548a085de55	25	*
pehrhovey	0:a548a085de55	26	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
pehrhovey	0:a548a085de55	27	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
pehrhovey	0:a548a085de55	28	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
pehrhovey	0:a548a085de55	29	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
pehrhovey	0:a548a085de55	30	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
pehrhovey	0:a548a085de55	31	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
pehrhovey	0:a548a085de55	32	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
pehrhovey	0:a548a085de55	33	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
pehrhovey	0:a548a085de55	34	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
pehrhovey	0:a548a085de55	35	* OF SUCH DAMAGE.
pehrhovey	0:a548a085de55	36	*
pehrhovey	0:a548a085de55	37	* This file is part of the lwIP TCP/IP stack.
pehrhovey	0:a548a085de55	38	*
pehrhovey	0:a548a085de55	39	* Author: Adam Dunkels <adam@sics.se>
pehrhovey	0:a548a085de55	40	*
pehrhovey	0:a548a085de55	41	*/
pehrhovey	0:a548a085de55	42
pehrhovey	0:a548a085de55	43	#include "lwip/opt.h"
pehrhovey	0:a548a085de55	44
pehrhovey	0:a548a085de55	45	#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
pehrhovey	0:a548a085de55	46
pehrhovey	0:a548a085de55	47	#include "lwip/def.h"
pehrhovey	0:a548a085de55	48	#include "lwip/mem.h"
pehrhovey	0:a548a085de55	49	#include "lwip/memp.h"
pehrhovey	0:a548a085de55	50	#include "lwip/snmp.h"
pehrhovey	0:a548a085de55	51	#include "lwip/tcp.h"
pehrhovey	0:a548a085de55	52	#include "lwip/debug.h"
pehrhovey	0:a548a085de55	53
pehrhovey	0:a548a085de55	54	#include <string.h>
pehrhovey	0:a548a085de55	55
pehrhovey	0:a548a085de55	56	const char *tcp_state_str[] = {
pehrhovey	0:a548a085de55	57	"CLOSED",
pehrhovey	0:a548a085de55	58	"LISTEN",
pehrhovey	0:a548a085de55	59	"SYN_SENT",
pehrhovey	0:a548a085de55	60	"SYN_RCVD",
pehrhovey	0:a548a085de55	61	"ESTABLISHED",
pehrhovey	0:a548a085de55	62	"FIN_WAIT_1",
pehrhovey	0:a548a085de55	63	"FIN_WAIT_2",
pehrhovey	0:a548a085de55	64	"CLOSE_WAIT",
pehrhovey	0:a548a085de55	65	"CLOSING",
pehrhovey	0:a548a085de55	66	"LAST_ACK",
pehrhovey	0:a548a085de55	67	"TIME_WAIT"
pehrhovey	0:a548a085de55	68	};
pehrhovey	0:a548a085de55	69
pehrhovey	0:a548a085de55	70	/* Incremented every coarse grained timer shot (typically every 500 ms). */
pehrhovey	0:a548a085de55	71	u32_t tcp_ticks;
pehrhovey	0:a548a085de55	72	const u8_t tcp_backoff[13] =
pehrhovey	0:a548a085de55	73	{ 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7};
pehrhovey	0:a548a085de55	74	/* Times per slowtmr hits */
pehrhovey	0:a548a085de55	75	const u8_t tcp_persist_backoff[7] = { 3, 6, 12, 24, 48, 96, 120 };
pehrhovey	0:a548a085de55	76
pehrhovey	0:a548a085de55	77	/* The TCP PCB lists. */
pehrhovey	0:a548a085de55	78
pehrhovey	0:a548a085de55	79	/** List of all TCP PCBs bound but not yet (connected \|\| listening) */
pehrhovey	0:a548a085de55	80	struct tcp_pcb *tcp_bound_pcbs;
pehrhovey	0:a548a085de55	81	/** List of all TCP PCBs in LISTEN state */
pehrhovey	0:a548a085de55	82	union tcp_listen_pcbs_t tcp_listen_pcbs;
pehrhovey	0:a548a085de55	83	/** List of all TCP PCBs that are in a state in which
pehrhovey	0:a548a085de55	84	* they accept or send data. */
pehrhovey	0:a548a085de55	85	struct tcp_pcb *tcp_active_pcbs;
pehrhovey	0:a548a085de55	86	/** List of all TCP PCBs in TIME-WAIT state */
pehrhovey	0:a548a085de55	87	struct tcp_pcb *tcp_tw_pcbs;
pehrhovey	0:a548a085de55	88
pehrhovey	0:a548a085de55	89	struct tcp_pcb *tcp_tmp_pcb;
pehrhovey	0:a548a085de55	90
pehrhovey	0:a548a085de55	91	static u8_t tcp_timer;
pehrhovey	0:a548a085de55	92	static u16_t tcp_new_port(void);
pehrhovey	0:a548a085de55	93
pehrhovey	0:a548a085de55	94	/**
pehrhovey	0:a548a085de55	95	* Called periodically to dispatch TCP timers.
pehrhovey	0:a548a085de55	96	*
pehrhovey	0:a548a085de55	97	*/
pehrhovey	0:a548a085de55	98	void
pehrhovey	0:a548a085de55	99	tcp_tmr(void)
pehrhovey	0:a548a085de55	100	{
pehrhovey	0:a548a085de55	101	/* Call tcp_fasttmr() every 250 ms */
pehrhovey	0:a548a085de55	102	tcp_fasttmr();
pehrhovey	0:a548a085de55	103
pehrhovey	0:a548a085de55	104	if (++tcp_timer & 1) {
pehrhovey	0:a548a085de55	105	/* Call tcp_tmr() every 500 ms, i.e., every other timer
pehrhovey	0:a548a085de55	106	tcp_tmr() is called. */
pehrhovey	0:a548a085de55	107	tcp_slowtmr();
pehrhovey	0:a548a085de55	108	}
pehrhovey	0:a548a085de55	109	}
pehrhovey	0:a548a085de55	110
pehrhovey	0:a548a085de55	111	/**
pehrhovey	0:a548a085de55	112	* Closes the connection held by the PCB.
pehrhovey	0:a548a085de55	113	*
pehrhovey	0:a548a085de55	114	* Listening pcbs are freed and may not be referenced any more.
pehrhovey	0:a548a085de55	115	* Connection pcbs are freed if not yet connected and may not be referenced
pehrhovey	0:a548a085de55	116	* any more. If a connection is established (at least SYN received or in
pehrhovey	0:a548a085de55	117	* a closing state), the connection is closed, and put in a closing state.
pehrhovey	0:a548a085de55	118	* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
pehrhovey	0:a548a085de55	119	* unsafe to reference it.
pehrhovey	0:a548a085de55	120	*
pehrhovey	0:a548a085de55	121	* @param pcb the tcp_pcb to close
pehrhovey	0:a548a085de55	122	* @return ERR_OK if connection has been closed
pehrhovey	0:a548a085de55	123	* another err_t if closing failed and pcb is not freed
pehrhovey	0:a548a085de55	124	*/
pehrhovey	0:a548a085de55	125	err_t
pehrhovey	0:a548a085de55	126	tcp_close(struct tcp_pcb *pcb)
pehrhovey	0:a548a085de55	127	{
pehrhovey	0:a548a085de55	128	err_t err;
pehrhovey	0:a548a085de55	129
pehrhovey	0:a548a085de55	130	#if TCP_DEBUG
pehrhovey	0:a548a085de55	131	LWIP_DEBUGF(TCP_DEBUG, ("tcp_close: closing in "));
pehrhovey	0:a548a085de55	132	tcp_debug_print_state(pcb->state);
pehrhovey	0:a548a085de55	133	#endif /* TCP_DEBUG */
pehrhovey	0:a548a085de55	134
pehrhovey	0:a548a085de55	135	switch (pcb->state) {
pehrhovey	0:a548a085de55	136	case CLOSED:
pehrhovey	0:a548a085de55	137	/* Closing a pcb in the CLOSED state might seem erroneous,
pehrhovey	0:a548a085de55	138	* however, it is in this state once allocated and as yet unused
pehrhovey	0:a548a085de55	139	* and the user needs some way to free it should the need arise.
pehrhovey	0:a548a085de55	140	* Calling tcp_close() with a pcb that has already been closed, (i.e. twice)
pehrhovey	0:a548a085de55	141	* or for a pcb that has been used and then entered the CLOSED state
pehrhovey	0:a548a085de55	142	* is erroneous, but this should never happen as the pcb has in those cases
pehrhovey	0:a548a085de55	143	* been freed, and so any remaining handles are bogus. */
pehrhovey	0:a548a085de55	144	err = ERR_OK;
pehrhovey	0:a548a085de55	145	TCP_RMV(&tcp_bound_pcbs, pcb);
pehrhovey	0:a548a085de55	146	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	147	pcb = NULL;
pehrhovey	0:a548a085de55	148	break;
pehrhovey	0:a548a085de55	149	case LISTEN:
pehrhovey	0:a548a085de55	150	err = ERR_OK;
pehrhovey	0:a548a085de55	151	tcp_pcb_remove((struct tcp_pcb **)&tcp_listen_pcbs.pcbs, pcb);
pehrhovey	0:a548a085de55	152	memp_free(MEMP_TCP_PCB_LISTEN, pcb);
pehrhovey	0:a548a085de55	153	pcb = NULL;
pehrhovey	0:a548a085de55	154	break;
pehrhovey	0:a548a085de55	155	case SYN_SENT:
pehrhovey	0:a548a085de55	156	err = ERR_OK;
pehrhovey	0:a548a085de55	157	tcp_pcb_remove(&tcp_active_pcbs, pcb);
pehrhovey	0:a548a085de55	158	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	159	pcb = NULL;
pehrhovey	0:a548a085de55	160	snmp_inc_tcpattemptfails();
pehrhovey	0:a548a085de55	161	break;
pehrhovey	0:a548a085de55	162	case SYN_RCVD:
pehrhovey	0:a548a085de55	163	err = tcp_send_ctrl(pcb, TCP_FIN);
pehrhovey	0:a548a085de55	164	if (err == ERR_OK) {
pehrhovey	0:a548a085de55	165	snmp_inc_tcpattemptfails();
pehrhovey	0:a548a085de55	166	pcb->state = FIN_WAIT_1;
pehrhovey	0:a548a085de55	167	}
pehrhovey	0:a548a085de55	168	break;
pehrhovey	0:a548a085de55	169	case ESTABLISHED:
pehrhovey	0:a548a085de55	170	err = tcp_send_ctrl(pcb, TCP_FIN);
pehrhovey	0:a548a085de55	171	if (err == ERR_OK) {
pehrhovey	0:a548a085de55	172	snmp_inc_tcpestabresets();
pehrhovey	0:a548a085de55	173	pcb->state = FIN_WAIT_1;
pehrhovey	0:a548a085de55	174	}
pehrhovey	0:a548a085de55	175	break;
pehrhovey	0:a548a085de55	176	case CLOSE_WAIT:
pehrhovey	0:a548a085de55	177	err = tcp_send_ctrl(pcb, TCP_FIN);
pehrhovey	0:a548a085de55	178	if (err == ERR_OK) {
pehrhovey	0:a548a085de55	179	snmp_inc_tcpestabresets();
pehrhovey	0:a548a085de55	180	pcb->state = LAST_ACK;
pehrhovey	0:a548a085de55	181	}
pehrhovey	0:a548a085de55	182	break;
pehrhovey	0:a548a085de55	183	default:
pehrhovey	0:a548a085de55	184	/* Has already been closed, do nothing. */
pehrhovey	0:a548a085de55	185	err = ERR_OK;
pehrhovey	0:a548a085de55	186	pcb = NULL;
pehrhovey	0:a548a085de55	187	break;
pehrhovey	0:a548a085de55	188	}
pehrhovey	0:a548a085de55	189
pehrhovey	0:a548a085de55	190	if (pcb != NULL && err == ERR_OK) {
pehrhovey	0:a548a085de55	191	/* To ensure all data has been sent when tcp_close returns, we have
pehrhovey	0:a548a085de55	192	to make sure tcp_output doesn't fail.
pehrhovey	0:a548a085de55	193	Since we don't really have to ensure all data has been sent when tcp_close
pehrhovey	0:a548a085de55	194	returns (unsent data is sent from tcp timer functions, also), we don't care
pehrhovey	0:a548a085de55	195	for the return value of tcp_output for now. */
pehrhovey	0:a548a085de55	196	/* @todo: When implementing SO_LINGER, this must be changed somehow:
pehrhovey	0:a548a085de55	197	If SOF_LINGER is set, the data should be sent when tcp_close returns. */
pehrhovey	0:a548a085de55	198	tcp_output(pcb);
pehrhovey	0:a548a085de55	199	}
pehrhovey	0:a548a085de55	200	return err;
pehrhovey	0:a548a085de55	201	}
pehrhovey	0:a548a085de55	202
pehrhovey	0:a548a085de55	203	/**
pehrhovey	0:a548a085de55	204	* Abandons a connection and optionally sends a RST to the remote
pehrhovey	0:a548a085de55	205	* host. Deletes the local protocol control block. This is done when
pehrhovey	0:a548a085de55	206	* a connection is killed because of shortage of memory.
pehrhovey	0:a548a085de55	207	*
pehrhovey	0:a548a085de55	208	* @param pcb the tcp_pcb to abort
pehrhovey	0:a548a085de55	209	* @param reset boolean to indicate whether a reset should be sent
pehrhovey	0:a548a085de55	210	*/
pehrhovey	0:a548a085de55	211	void
pehrhovey	0:a548a085de55	212	tcp_abandon(struct tcp_pcb *pcb, int reset)
pehrhovey	0:a548a085de55	213	{
pehrhovey	0:a548a085de55	214	u32_t seqno, ackno;
pehrhovey	0:a548a085de55	215	u16_t remote_port, local_port;
pehrhovey	0:a548a085de55	216	struct ip_addr remote_ip, local_ip;
pehrhovey	0:a548a085de55	217	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	218	void (* errf)(void *arg, err_t err);
pehrhovey	0:a548a085de55	219	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	220	void *errf_arg;
pehrhovey	0:a548a085de55	221
pehrhovey	0:a548a085de55	222
pehrhovey	0:a548a085de55	223	/* Figure out on which TCP PCB list we are, and remove us. If we
pehrhovey	0:a548a085de55	224	are in an active state, call the receive function associated with
pehrhovey	0:a548a085de55	225	the PCB with a NULL argument, and send an RST to the remote end. */
pehrhovey	0:a548a085de55	226	if (pcb->state == TIME_WAIT) {
pehrhovey	0:a548a085de55	227	tcp_pcb_remove(&tcp_tw_pcbs, pcb);
pehrhovey	0:a548a085de55	228	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	229	} else {
pehrhovey	0:a548a085de55	230	seqno = pcb->snd_nxt;
pehrhovey	0:a548a085de55	231	ackno = pcb->rcv_nxt;
pehrhovey	0:a548a085de55	232	ip_addr_set(&local_ip, &(pcb->local_ip));
pehrhovey	0:a548a085de55	233	ip_addr_set(&remote_ip, &(pcb->remote_ip));
pehrhovey	0:a548a085de55	234	local_port = pcb->local_port;
pehrhovey	0:a548a085de55	235	remote_port = pcb->remote_port;
pehrhovey	0:a548a085de55	236	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	237	errf = pcb->errf;
pehrhovey	0:a548a085de55	238	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	239	errf_arg = pcb->callback_arg;
pehrhovey	0:a548a085de55	240	tcp_pcb_remove(&tcp_active_pcbs, pcb);
pehrhovey	0:a548a085de55	241	if (pcb->unacked != NULL) {
pehrhovey	0:a548a085de55	242	tcp_segs_free(pcb->unacked);
pehrhovey	0:a548a085de55	243	}
pehrhovey	0:a548a085de55	244	if (pcb->unsent != NULL) {
pehrhovey	0:a548a085de55	245	tcp_segs_free(pcb->unsent);
pehrhovey	0:a548a085de55	246	}
pehrhovey	0:a548a085de55	247	#if TCP_QUEUE_OOSEQ
pehrhovey	0:a548a085de55	248	if (pcb->ooseq != NULL) {
pehrhovey	0:a548a085de55	249	tcp_segs_free(pcb->ooseq);
pehrhovey	0:a548a085de55	250	}
pehrhovey	0:a548a085de55	251	#endif /* TCP_QUEUE_OOSEQ */
pehrhovey	0:a548a085de55	252	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	253	TCP_EVENT_ERR(errf, errf_arg, ERR_ABRT);
pehrhovey	0:a548a085de55	254	if (reset) {
pehrhovey	0:a548a085de55	255	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_abandon: sending RST\n"));
pehrhovey	0:a548a085de55	256	tcp_rst(seqno, ackno, &local_ip, &remote_ip, local_port, remote_port);
pehrhovey	0:a548a085de55	257	}
pehrhovey	0:a548a085de55	258	}
pehrhovey	0:a548a085de55	259	}
pehrhovey	0:a548a085de55	260
pehrhovey	0:a548a085de55	261	/**
pehrhovey	0:a548a085de55	262	* Binds the connection to a local portnumber and IP address. If the
pehrhovey	0:a548a085de55	263	* IP address is not given (i.e., ipaddr == NULL), the IP address of
pehrhovey	0:a548a085de55	264	* the outgoing network interface is used instead.
pehrhovey	0:a548a085de55	265	*
pehrhovey	0:a548a085de55	266	* @param pcb the tcp_pcb to bind (no check is done whether this pcb is
pehrhovey	0:a548a085de55	267	* already bound!)
pehrhovey	0:a548a085de55	268	* @param ipaddr the local ip address to bind to (use IP_ADDR_ANY to bind
pehrhovey	0:a548a085de55	269	* to any local address
pehrhovey	0:a548a085de55	270	* @param port the local port to bind to
pehrhovey	0:a548a085de55	271	* @return ERR_USE if the port is already in use
pehrhovey	0:a548a085de55	272	* ERR_OK if bound
pehrhovey	0:a548a085de55	273	*/
pehrhovey	0:a548a085de55	274	err_t
pehrhovey	0:a548a085de55	275	tcp_bind(struct tcp_pcb pcb, struct ip_addr ipaddr, u16_t port)
pehrhovey	0:a548a085de55	276	{
pehrhovey	0:a548a085de55	277	struct tcp_pcb *cpcb;
pehrhovey	0:a548a085de55	278
pehrhovey	0:a548a085de55	279	LWIP_ERROR("tcp_bind: can only bind in state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
pehrhovey	0:a548a085de55	280
pehrhovey	0:a548a085de55	281	if (port == 0) {
pehrhovey	0:a548a085de55	282	port = tcp_new_port();
pehrhovey	0:a548a085de55	283	}
pehrhovey	0:a548a085de55	284	/* Check if the address already is in use. */
pehrhovey	0:a548a085de55	285	/* Check the listen pcbs. */
pehrhovey	0:a548a085de55	286	for(cpcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs;
pehrhovey	0:a548a085de55	287	cpcb != NULL; cpcb = cpcb->next) {
pehrhovey	0:a548a085de55	288	if (cpcb->local_port == port) {
pehrhovey	0:a548a085de55	289	if (ip_addr_isany(&(cpcb->local_ip)) \|\|
pehrhovey	0:a548a085de55	290	ip_addr_isany(ipaddr) \|\|
pehrhovey	0:a548a085de55	291	ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
pehrhovey	0:a548a085de55	292	return ERR_USE;
pehrhovey	0:a548a085de55	293	}
pehrhovey	0:a548a085de55	294	}
pehrhovey	0:a548a085de55	295	}
pehrhovey	0:a548a085de55	296	/* Check the connected pcbs. */
pehrhovey	0:a548a085de55	297	for(cpcb = tcp_active_pcbs;
pehrhovey	0:a548a085de55	298	cpcb != NULL; cpcb = cpcb->next) {
pehrhovey	0:a548a085de55	299	if (cpcb->local_port == port) {
pehrhovey	0:a548a085de55	300	if (ip_addr_isany(&(cpcb->local_ip)) \|\|
pehrhovey	0:a548a085de55	301	ip_addr_isany(ipaddr) \|\|
pehrhovey	0:a548a085de55	302	ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
pehrhovey	0:a548a085de55	303	return ERR_USE;
pehrhovey	0:a548a085de55	304	}
pehrhovey	0:a548a085de55	305	}
pehrhovey	0:a548a085de55	306	}
pehrhovey	0:a548a085de55	307	/* Check the bound, not yet connected pcbs. */
pehrhovey	0:a548a085de55	308	for(cpcb = tcp_bound_pcbs; cpcb != NULL; cpcb = cpcb->next) {
pehrhovey	0:a548a085de55	309	if (cpcb->local_port == port) {
pehrhovey	0:a548a085de55	310	if (ip_addr_isany(&(cpcb->local_ip)) \|\|
pehrhovey	0:a548a085de55	311	ip_addr_isany(ipaddr) \|\|
pehrhovey	0:a548a085de55	312	ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
pehrhovey	0:a548a085de55	313	return ERR_USE;
pehrhovey	0:a548a085de55	314	}
pehrhovey	0:a548a085de55	315	}
pehrhovey	0:a548a085de55	316	}
pehrhovey	0:a548a085de55	317	/* @todo: until SO_REUSEADDR is implemented (see task #6995 on savannah),
pehrhovey	0:a548a085de55	318	* we have to check the pcbs in TIME-WAIT state, also: */
pehrhovey	0:a548a085de55	319	for(cpcb = tcp_tw_pcbs; cpcb != NULL; cpcb = cpcb->next) {
pehrhovey	0:a548a085de55	320	if (cpcb->local_port == port) {
pehrhovey	0:a548a085de55	321	if (ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
pehrhovey	0:a548a085de55	322	return ERR_USE;
pehrhovey	0:a548a085de55	323	}
pehrhovey	0:a548a085de55	324	}
pehrhovey	0:a548a085de55	325	}
pehrhovey	0:a548a085de55	326
pehrhovey	0:a548a085de55	327	if (!ip_addr_isany(ipaddr)) {
pehrhovey	0:a548a085de55	328	pcb->local_ip = *ipaddr;
pehrhovey	0:a548a085de55	329	}
pehrhovey	0:a548a085de55	330	pcb->local_port = port;
pehrhovey	0:a548a085de55	331	TCP_REG(&tcp_bound_pcbs, pcb);
pehrhovey	0:a548a085de55	332	LWIP_DEBUGF(TCP_DEBUG, ("tcp_bind: bind to port %"U16_F"\n", port));
pehrhovey	0:a548a085de55	333	return ERR_OK;
pehrhovey	0:a548a085de55	334	}
pehrhovey	0:a548a085de55	335	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	336	/**
pehrhovey	0:a548a085de55	337	* Default accept callback if no accept callback is specified by the user.
pehrhovey	0:a548a085de55	338	*/
pehrhovey	0:a548a085de55	339	static err_t
pehrhovey	0:a548a085de55	340	tcp_accept_null(void arg, struct tcp_pcb pcb, err_t err)
pehrhovey	0:a548a085de55	341	{
pehrhovey	0:a548a085de55	342	LWIP_UNUSED_ARG(arg);
pehrhovey	0:a548a085de55	343	LWIP_UNUSED_ARG(pcb);
pehrhovey	0:a548a085de55	344	LWIP_UNUSED_ARG(err);
pehrhovey	0:a548a085de55	345
pehrhovey	0:a548a085de55	346	return ERR_ABRT;
pehrhovey	0:a548a085de55	347	}
pehrhovey	0:a548a085de55	348	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	349
pehrhovey	0:a548a085de55	350	/**
pehrhovey	0:a548a085de55	351	* Set the state of the connection to be LISTEN, which means that it
pehrhovey	0:a548a085de55	352	* is able to accept incoming connections. The protocol control block
pehrhovey	0:a548a085de55	353	* is reallocated in order to consume less memory. Setting the
pehrhovey	0:a548a085de55	354	* connection to LISTEN is an irreversible process.
pehrhovey	0:a548a085de55	355	*
pehrhovey	0:a548a085de55	356	* @param pcb the original tcp_pcb
pehrhovey	0:a548a085de55	357	* @param backlog the incoming connections queue limit
pehrhovey	0:a548a085de55	358	* @return tcp_pcb used for listening, consumes less memory.
pehrhovey	0:a548a085de55	359	*
pehrhovey	0:a548a085de55	360	* @note The original tcp_pcb is freed. This function therefore has to be
pehrhovey	0:a548a085de55	361	* called like this:
pehrhovey	0:a548a085de55	362	* tpcb = tcp_listen(tpcb);
pehrhovey	0:a548a085de55	363	*/
pehrhovey	0:a548a085de55	364	struct tcp_pcb *
pehrhovey	0:a548a085de55	365	tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
pehrhovey	0:a548a085de55	366	{
pehrhovey	0:a548a085de55	367	struct tcp_pcb_listen *lpcb;
pehrhovey	0:a548a085de55	368
pehrhovey	0:a548a085de55	369	LWIP_UNUSED_ARG(backlog);
pehrhovey	0:a548a085de55	370	LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
pehrhovey	0:a548a085de55	371
pehrhovey	0:a548a085de55	372	/* already listening? */
pehrhovey	0:a548a085de55	373	if (pcb->state == LISTEN) {
pehrhovey	0:a548a085de55	374	return pcb;
pehrhovey	0:a548a085de55	375	}
pehrhovey	0:a548a085de55	376	lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);
pehrhovey	0:a548a085de55	377	if (lpcb == NULL) {
pehrhovey	0:a548a085de55	378	return NULL;
pehrhovey	0:a548a085de55	379	}
pehrhovey	0:a548a085de55	380	lpcb->callback_arg = pcb->callback_arg;
pehrhovey	0:a548a085de55	381	lpcb->local_port = pcb->local_port;
pehrhovey	0:a548a085de55	382	lpcb->state = LISTEN;
pehrhovey	0:a548a085de55	383	lpcb->so_options = pcb->so_options;
pehrhovey	0:a548a085de55	384	lpcb->so_options \|= SOF_ACCEPTCONN;
pehrhovey	0:a548a085de55	385	lpcb->ttl = pcb->ttl;
pehrhovey	0:a548a085de55	386	lpcb->tos = pcb->tos;
pehrhovey	0:a548a085de55	387	ip_addr_set(&lpcb->local_ip, &pcb->local_ip);
pehrhovey	0:a548a085de55	388	TCP_RMV(&tcp_bound_pcbs, pcb);
pehrhovey	0:a548a085de55	389	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	390	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	391	lpcb->accept = tcp_accept_null;
pehrhovey	0:a548a085de55	392	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	393	#if TCP_LISTEN_BACKLOG
pehrhovey	0:a548a085de55	394	lpcb->accepts_pending = 0;
pehrhovey	0:a548a085de55	395	lpcb->backlog = (backlog ? backlog : 1);
pehrhovey	0:a548a085de55	396	#endif /* TCP_LISTEN_BACKLOG */
pehrhovey	0:a548a085de55	397	TCP_REG(&tcp_listen_pcbs.listen_pcbs, lpcb);
pehrhovey	0:a548a085de55	398	return (struct tcp_pcb *)lpcb;
pehrhovey	0:a548a085de55	399	}
pehrhovey	0:a548a085de55	400
pehrhovey	0:a548a085de55	401	/**
pehrhovey	0:a548a085de55	402	* Update the state that tracks the available window space to advertise.
pehrhovey	0:a548a085de55	403	*
pehrhovey	0:a548a085de55	404	* Returns how much extra window would be advertised if we sent an
pehrhovey	0:a548a085de55	405	* update now.
pehrhovey	0:a548a085de55	406	*/
pehrhovey	0:a548a085de55	407	u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb)
pehrhovey	0:a548a085de55	408	{
pehrhovey	0:a548a085de55	409	u32_t new_right_edge = pcb->rcv_nxt + pcb->rcv_wnd;
pehrhovey	0:a548a085de55	410
pehrhovey	0:a548a085de55	411	if (TCP_SEQ_GEQ(new_right_edge, pcb->rcv_ann_right_edge + LWIP_MIN((TCP_WND / 2), pcb->mss))) {
pehrhovey	0:a548a085de55	412	/* we can advertise more window */
pehrhovey	0:a548a085de55	413	pcb->rcv_ann_wnd = pcb->rcv_wnd;
pehrhovey	0:a548a085de55	414	return new_right_edge - pcb->rcv_ann_right_edge;
pehrhovey	0:a548a085de55	415	} else {
pehrhovey	0:a548a085de55	416	if (TCP_SEQ_GT(pcb->rcv_nxt, pcb->rcv_ann_right_edge)) {
pehrhovey	0:a548a085de55	417	/* Can happen due to other end sending out of advertised window,
pehrhovey	0:a548a085de55	418	* but within actual available (but not yet advertised) window */
pehrhovey	0:a548a085de55	419	pcb->rcv_ann_wnd = 0;
pehrhovey	0:a548a085de55	420	} else {
pehrhovey	0:a548a085de55	421	/* keep the right edge of window constant */
pehrhovey	0:a548a085de55	422	pcb->rcv_ann_wnd = pcb->rcv_ann_right_edge - pcb->rcv_nxt;
pehrhovey	0:a548a085de55	423	}
pehrhovey	0:a548a085de55	424	return 0;
pehrhovey	0:a548a085de55	425	}
pehrhovey	0:a548a085de55	426	}
pehrhovey	0:a548a085de55	427
pehrhovey	0:a548a085de55	428	/**
pehrhovey	0:a548a085de55	429	* This function should be called by the application when it has
pehrhovey	0:a548a085de55	430	* processed the data. The purpose is to advertise a larger window
pehrhovey	0:a548a085de55	431	* when the data has been processed.
pehrhovey	0:a548a085de55	432	*
pehrhovey	0:a548a085de55	433	* @param pcb the tcp_pcb for which data is read
pehrhovey	0:a548a085de55	434	* @param len the amount of bytes that have been read by the application
pehrhovey	0:a548a085de55	435	*/
pehrhovey	0:a548a085de55	436	void
pehrhovey	0:a548a085de55	437	tcp_recved(struct tcp_pcb *pcb, u16_t len)
pehrhovey	0:a548a085de55	438	{
pehrhovey	0:a548a085de55	439	int wnd_inflation;
pehrhovey	0:a548a085de55	440
pehrhovey	0:a548a085de55	441	LWIP_ASSERT("tcp_recved: len would wrap rcv_wnd\n",
pehrhovey	0:a548a085de55	442	len <= 0xffff - pcb->rcv_wnd );
pehrhovey	0:a548a085de55	443
pehrhovey	0:a548a085de55	444	pcb->rcv_wnd += len;
pehrhovey	0:a548a085de55	445	if (pcb->rcv_wnd > TCP_WND)
pehrhovey	0:a548a085de55	446	pcb->rcv_wnd = TCP_WND;
pehrhovey	0:a548a085de55	447
pehrhovey	0:a548a085de55	448	wnd_inflation = tcp_update_rcv_ann_wnd(pcb);
pehrhovey	0:a548a085de55	449
pehrhovey	0:a548a085de55	450	/* If the change in the right edge of window is significant (default
pehrhovey	0:a548a085de55	451	* watermark is TCP_WND/2), then send an explicit update now.
pehrhovey	0:a548a085de55	452	* Otherwise wait for a packet to be sent in the normal course of
pehrhovey	0:a548a085de55	453	* events (or more window to be available later) */
pehrhovey	0:a548a085de55	454	if (wnd_inflation >= TCP_WND_UPDATE_THRESHOLD)
pehrhovey	0:a548a085de55	455	tcp_ack_now(pcb);
pehrhovey	0:a548a085de55	456
pehrhovey	0:a548a085de55	457	LWIP_DEBUGF(TCP_DEBUG, ("tcp_recved: recveived %"U16_F" bytes, wnd %"U16_F" (%"U16_F").\n",
pehrhovey	0:a548a085de55	458	len, pcb->rcv_wnd, TCP_WND - pcb->rcv_wnd));
pehrhovey	0:a548a085de55	459	}
pehrhovey	0:a548a085de55	460
pehrhovey	0:a548a085de55	461	/**
pehrhovey	0:a548a085de55	462	* A nastly hack featuring 'goto' statements that allocates a
pehrhovey	0:a548a085de55	463	* new TCP local port.
pehrhovey	0:a548a085de55	464	*
pehrhovey	0:a548a085de55	465	* @return a new (free) local TCP port number
pehrhovey	0:a548a085de55	466	*/
pehrhovey	0:a548a085de55	467	static u16_t
pehrhovey	0:a548a085de55	468	tcp_new_port(void)
pehrhovey	0:a548a085de55	469	{
pehrhovey	0:a548a085de55	470	struct tcp_pcb *pcb;
pehrhovey	0:a548a085de55	471	#ifndef TCP_LOCAL_PORT_RANGE_START
pehrhovey	0:a548a085de55	472	#define TCP_LOCAL_PORT_RANGE_START 4096
pehrhovey	0:a548a085de55	473	#define TCP_LOCAL_PORT_RANGE_END 0x7fff
pehrhovey	0:a548a085de55	474	#endif
pehrhovey	0:a548a085de55	475	static u16_t port = TCP_LOCAL_PORT_RANGE_START;
pehrhovey	0:a548a085de55	476
pehrhovey	0:a548a085de55	477	again:
pehrhovey	0:a548a085de55	478	if (++port > TCP_LOCAL_PORT_RANGE_END) {
pehrhovey	0:a548a085de55	479	port = TCP_LOCAL_PORT_RANGE_START;
pehrhovey	0:a548a085de55	480	}
pehrhovey	0:a548a085de55	481
pehrhovey	0:a548a085de55	482	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	483	if (pcb->local_port == port) {
pehrhovey	0:a548a085de55	484	goto again;
pehrhovey	0:a548a085de55	485	}
pehrhovey	0:a548a085de55	486	}
pehrhovey	0:a548a085de55	487	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	488	if (pcb->local_port == port) {
pehrhovey	0:a548a085de55	489	goto again;
pehrhovey	0:a548a085de55	490	}
pehrhovey	0:a548a085de55	491	}
pehrhovey	0:a548a085de55	492	for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	493	if (pcb->local_port == port) {
pehrhovey	0:a548a085de55	494	goto again;
pehrhovey	0:a548a085de55	495	}
pehrhovey	0:a548a085de55	496	}
pehrhovey	0:a548a085de55	497	return port;
pehrhovey	0:a548a085de55	498	}
pehrhovey	0:a548a085de55	499
pehrhovey	0:a548a085de55	500	/**
pehrhovey	0:a548a085de55	501	* Connects to another host. The function given as the "connected"
pehrhovey	0:a548a085de55	502	* argument will be called when the connection has been established.
pehrhovey	0:a548a085de55	503	*
pehrhovey	0:a548a085de55	504	* @param pcb the tcp_pcb used to establish the connection
pehrhovey	0:a548a085de55	505	* @param ipaddr the remote ip address to connect to
pehrhovey	0:a548a085de55	506	* @param port the remote tcp port to connect to
pehrhovey	0:a548a085de55	507	* @param connected callback function to call when connected (or on error)
pehrhovey	0:a548a085de55	508	* @return ERR_VAL if invalid arguments are given
pehrhovey	0:a548a085de55	509	* ERR_OK if connect request has been sent
pehrhovey	0:a548a085de55	510	* other err_t values if connect request couldn't be sent
pehrhovey	0:a548a085de55	511	*/
pehrhovey	0:a548a085de55	512	err_t
pehrhovey	0:a548a085de55	513	tcp_connect(struct tcp_pcb pcb, struct ip_addr ipaddr, u16_t port,
pehrhovey	0:a548a085de55	514	err_t (* connected)(void arg, struct tcp_pcb tpcb, err_t err))
pehrhovey	0:a548a085de55	515	{
pehrhovey	0:a548a085de55	516	err_t ret;
pehrhovey	0:a548a085de55	517	u32_t iss;
pehrhovey	0:a548a085de55	518
pehrhovey	0:a548a085de55	519	LWIP_ERROR("tcp_connect: can only connected from state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
pehrhovey	0:a548a085de55	520
pehrhovey	0:a548a085de55	521	LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect to port %"U16_F"\n", port));
pehrhovey	0:a548a085de55	522	if (ipaddr != NULL) {
pehrhovey	0:a548a085de55	523	pcb->remote_ip = *ipaddr;
pehrhovey	0:a548a085de55	524	} else {
pehrhovey	0:a548a085de55	525	return ERR_VAL;
pehrhovey	0:a548a085de55	526	}
pehrhovey	0:a548a085de55	527	pcb->remote_port = port;
pehrhovey	0:a548a085de55	528	if (pcb->local_port == 0) {
pehrhovey	0:a548a085de55	529	pcb->local_port = tcp_new_port();
pehrhovey	0:a548a085de55	530	}
pehrhovey	0:a548a085de55	531	iss = tcp_next_iss();
pehrhovey	0:a548a085de55	532	pcb->rcv_nxt = 0;
pehrhovey	0:a548a085de55	533	pcb->snd_nxt = iss;
pehrhovey	0:a548a085de55	534	pcb->lastack = iss - 1;
pehrhovey	0:a548a085de55	535	pcb->snd_lbb = iss - 1;
pehrhovey	0:a548a085de55	536	pcb->rcv_wnd = TCP_WND;
pehrhovey	0:a548a085de55	537	pcb->rcv_ann_wnd = TCP_WND;
pehrhovey	0:a548a085de55	538	pcb->rcv_ann_right_edge = pcb->rcv_nxt;
pehrhovey	0:a548a085de55	539	pcb->snd_wnd = TCP_WND;
pehrhovey	0:a548a085de55	540	/* As initial send MSS, we use TCP_MSS but limit it to 536.
pehrhovey	0:a548a085de55	541	The send MSS is updated when an MSS option is received. */
pehrhovey	0:a548a085de55	542	pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
pehrhovey	0:a548a085de55	543	#if TCP_CALCULATE_EFF_SEND_MSS
pehrhovey	0:a548a085de55	544	pcb->mss = tcp_eff_send_mss(pcb->mss, ipaddr);
pehrhovey	0:a548a085de55	545	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
pehrhovey	0:a548a085de55	546	pcb->cwnd = 1;
pehrhovey	0:a548a085de55	547	pcb->ssthresh = pcb->mss * 10;
pehrhovey	0:a548a085de55	548	pcb->state = SYN_SENT;
pehrhovey	0:a548a085de55	549	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	550	pcb->connected = connected;
pehrhovey	0:a548a085de55	551	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	552	TCP_RMV(&tcp_bound_pcbs, pcb);
pehrhovey	0:a548a085de55	553	TCP_REG(&tcp_active_pcbs, pcb);
pehrhovey	0:a548a085de55	554
pehrhovey	0:a548a085de55	555	snmp_inc_tcpactiveopens();
pehrhovey	0:a548a085de55	556
pehrhovey	0:a548a085de55	557	ret = tcp_enqueue(pcb, NULL, 0, TCP_SYN, 0, TF_SEG_OPTS_MSS
pehrhovey	0:a548a085de55	558	#if LWIP_TCP_TIMESTAMPS
pehrhovey	0:a548a085de55	559	\| TF_SEG_OPTS_TS
pehrhovey	0:a548a085de55	560	#endif
pehrhovey	0:a548a085de55	561	);
pehrhovey	0:a548a085de55	562	if (ret == ERR_OK) {
pehrhovey	0:a548a085de55	563	tcp_output(pcb);
pehrhovey	0:a548a085de55	564	}
pehrhovey	0:a548a085de55	565	return ret;
pehrhovey	0:a548a085de55	566	}
pehrhovey	0:a548a085de55	567
pehrhovey	0:a548a085de55	568	/**
pehrhovey	0:a548a085de55	569	* Called every 500 ms and implements the retransmission timer and the timer that
pehrhovey	0:a548a085de55	570	* removes PCBs that have been in TIME-WAIT for enough time. It also increments
pehrhovey	0:a548a085de55	571	* various timers such as the inactivity timer in each PCB.
pehrhovey	0:a548a085de55	572	*
pehrhovey	0:a548a085de55	573	* Automatically called from tcp_tmr().
pehrhovey	0:a548a085de55	574	*/
pehrhovey	0:a548a085de55	575	void
pehrhovey	0:a548a085de55	576	tcp_slowtmr(void)
pehrhovey	0:a548a085de55	577	{
pehrhovey	0:a548a085de55	578	struct tcp_pcb pcb, pcb2, *prev;
pehrhovey	0:a548a085de55	579	u16_t eff_wnd;
pehrhovey	0:a548a085de55	580	u8_t pcb_remove; /* flag if a PCB should be removed */
pehrhovey	0:a548a085de55	581	err_t err;
pehrhovey	0:a548a085de55	582
pehrhovey	0:a548a085de55	583	err = ERR_OK;
pehrhovey	0:a548a085de55	584
pehrhovey	0:a548a085de55	585	++tcp_ticks;
pehrhovey	0:a548a085de55	586
pehrhovey	0:a548a085de55	587	/* Steps through all of the active PCBs. */
pehrhovey	0:a548a085de55	588	prev = NULL;
pehrhovey	0:a548a085de55	589	pcb = tcp_active_pcbs;
pehrhovey	0:a548a085de55	590	if (pcb == NULL) {
pehrhovey	0:a548a085de55	591	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: no active pcbs\n"));
pehrhovey	0:a548a085de55	592	}
pehrhovey	0:a548a085de55	593	while (pcb != NULL) {
pehrhovey	0:a548a085de55	594	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: processing active pcb\n"));
pehrhovey	0:a548a085de55	595	LWIP_ASSERT("tcp_slowtmr: active pcb->state != CLOSED\n", pcb->state != CLOSED);
pehrhovey	0:a548a085de55	596	LWIP_ASSERT("tcp_slowtmr: active pcb->state != LISTEN\n", pcb->state != LISTEN);
pehrhovey	0:a548a085de55	597	LWIP_ASSERT("tcp_slowtmr: active pcb->state != TIME-WAIT\n", pcb->state != TIME_WAIT);
pehrhovey	0:a548a085de55	598
pehrhovey	0:a548a085de55	599	pcb_remove = 0;
pehrhovey	0:a548a085de55	600
pehrhovey	0:a548a085de55	601	if (pcb->state == SYN_SENT && pcb->nrtx == TCP_SYNMAXRTX) {
pehrhovey	0:a548a085de55	602	++pcb_remove;
pehrhovey	0:a548a085de55	603	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max SYN retries reached\n"));
pehrhovey	0:a548a085de55	604	}
pehrhovey	0:a548a085de55	605	else if (pcb->nrtx == TCP_MAXRTX) {
pehrhovey	0:a548a085de55	606	++pcb_remove;
pehrhovey	0:a548a085de55	607	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max DATA retries reached\n"));
pehrhovey	0:a548a085de55	608	} else {
pehrhovey	0:a548a085de55	609	if (pcb->persist_backoff > 0) {
pehrhovey	0:a548a085de55	610	/* If snd_wnd is zero, use persist timer to send 1 byte probes
pehrhovey	0:a548a085de55	611	* instead of using the standard retransmission mechanism. */
pehrhovey	0:a548a085de55	612	pcb->persist_cnt++;
pehrhovey	0:a548a085de55	613	if (pcb->persist_cnt >= tcp_persist_backoff[pcb->persist_backoff-1]) {
pehrhovey	0:a548a085de55	614	pcb->persist_cnt = 0;
pehrhovey	0:a548a085de55	615	if (pcb->persist_backoff < sizeof(tcp_persist_backoff)) {
pehrhovey	0:a548a085de55	616	pcb->persist_backoff++;
pehrhovey	0:a548a085de55	617	}
pehrhovey	0:a548a085de55	618	tcp_zero_window_probe(pcb);
pehrhovey	0:a548a085de55	619	}
pehrhovey	0:a548a085de55	620	} else {
pehrhovey	0:a548a085de55	621	/* Increase the retransmission timer if it is running */
pehrhovey	0:a548a085de55	622	if(pcb->rtime >= 0)
pehrhovey	0:a548a085de55	623	++pcb->rtime;
pehrhovey	0:a548a085de55	624
pehrhovey	0:a548a085de55	625	if (pcb->unacked != NULL && pcb->rtime >= pcb->rto) {
pehrhovey	0:a548a085de55	626	/* Time for a retransmission. */
pehrhovey	0:a548a085de55	627	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_slowtmr: rtime %"S16_F
pehrhovey	0:a548a085de55	628	" pcb->rto %"S16_F"\n",
pehrhovey	0:a548a085de55	629	pcb->rtime, pcb->rto));
pehrhovey	0:a548a085de55	630
pehrhovey	0:a548a085de55	631	/* Double retransmission time-out unless we are trying to
pehrhovey	0:a548a085de55	632	* connect to somebody (i.e., we are in SYN_SENT). */
pehrhovey	0:a548a085de55	633	if (pcb->state != SYN_SENT) {
pehrhovey	0:a548a085de55	634	pcb->rto = ((pcb->sa >> 3) + pcb->sv) << tcp_backoff[pcb->nrtx];
pehrhovey	0:a548a085de55	635	}
pehrhovey	0:a548a085de55	636
pehrhovey	0:a548a085de55	637	/* Reset the retransmission timer. */
pehrhovey	0:a548a085de55	638	pcb->rtime = 0;
pehrhovey	0:a548a085de55	639
pehrhovey	0:a548a085de55	640	/* Reduce congestion window and ssthresh. */
pehrhovey	0:a548a085de55	641	eff_wnd = LWIP_MIN(pcb->cwnd, pcb->snd_wnd);
pehrhovey	0:a548a085de55	642	pcb->ssthresh = eff_wnd >> 1;
pehrhovey	0:a548a085de55	643	if (pcb->ssthresh < pcb->mss) {
pehrhovey	0:a548a085de55	644	pcb->ssthresh = pcb->mss * 2;
pehrhovey	0:a548a085de55	645	}
pehrhovey	0:a548a085de55	646	pcb->cwnd = pcb->mss;
pehrhovey	0:a548a085de55	647	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: cwnd %"U16_F
pehrhovey	0:a548a085de55	648	" ssthresh %"U16_F"\n",
pehrhovey	0:a548a085de55	649	pcb->cwnd, pcb->ssthresh));
pehrhovey	0:a548a085de55	650
pehrhovey	0:a548a085de55	651	/* The following needs to be called AFTER cwnd is set to one
pehrhovey	0:a548a085de55	652	mss - STJ */
pehrhovey	0:a548a085de55	653	tcp_rexmit_rto(pcb);
pehrhovey	0:a548a085de55	654	}
pehrhovey	0:a548a085de55	655	}
pehrhovey	0:a548a085de55	656	}
pehrhovey	0:a548a085de55	657	/* Check if this PCB has stayed too long in FIN-WAIT-2 */
pehrhovey	0:a548a085de55	658	if (pcb->state == FIN_WAIT_2) {
pehrhovey	0:a548a085de55	659	if ((u32_t)(tcp_ticks - pcb->tmr) >
pehrhovey	0:a548a085de55	660	TCP_FIN_WAIT_TIMEOUT / TCP_SLOW_INTERVAL) {
pehrhovey	0:a548a085de55	661	++pcb_remove;
pehrhovey	0:a548a085de55	662	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in FIN-WAIT-2\n"));
pehrhovey	0:a548a085de55	663	}
pehrhovey	0:a548a085de55	664	}
pehrhovey	0:a548a085de55	665
pehrhovey	0:a548a085de55	666	/* Check if KEEPALIVE should be sent */
pehrhovey	0:a548a085de55	667	if((pcb->so_options & SOF_KEEPALIVE) &&
pehrhovey	0:a548a085de55	668	((pcb->state == ESTABLISHED) \|\|
pehrhovey	0:a548a085de55	669	(pcb->state == CLOSE_WAIT))) {
pehrhovey	0:a548a085de55	670	#if LWIP_TCP_KEEPALIVE
pehrhovey	0:a548a085de55	671	if((u32_t)(tcp_ticks - pcb->tmr) >
pehrhovey	0:a548a085de55	672	(pcb->keep_idle + (pcb->keep_cnt*pcb->keep_intvl))
pehrhovey	0:a548a085de55	673	/ TCP_SLOW_INTERVAL)
pehrhovey	0:a548a085de55	674	#else
pehrhovey	0:a548a085de55	675	if((u32_t)(tcp_ticks - pcb->tmr) >
pehrhovey	0:a548a085de55	676	(pcb->keep_idle + TCP_MAXIDLE) / TCP_SLOW_INTERVAL)
pehrhovey	0:a548a085de55	677	#endif /* LWIP_TCP_KEEPALIVE */
pehrhovey	0:a548a085de55	678	{
pehrhovey	0:a548a085de55	679	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: KEEPALIVE timeout. Aborting connection to %"U16_F".%"U16_F".%"U16_F".%"U16_F".\n",
pehrhovey	0:a548a085de55	680	ip4_addr1(&pcb->remote_ip), ip4_addr2(&pcb->remote_ip),
pehrhovey	0:a548a085de55	681	ip4_addr3(&pcb->remote_ip), ip4_addr4(&pcb->remote_ip)));
pehrhovey	0:a548a085de55	682
pehrhovey	0:a548a085de55	683	tcp_abort(pcb);
pehrhovey	0:a548a085de55	684	}
pehrhovey	0:a548a085de55	685	#if LWIP_TCP_KEEPALIVE
pehrhovey	0:a548a085de55	686	else if((u32_t)(tcp_ticks - pcb->tmr) >
pehrhovey	0:a548a085de55	687	(pcb->keep_idle + pcb->keep_cnt_sent * pcb->keep_intvl)
pehrhovey	0:a548a085de55	688	/ TCP_SLOW_INTERVAL)
pehrhovey	0:a548a085de55	689	#else
pehrhovey	0:a548a085de55	690	else if((u32_t)(tcp_ticks - pcb->tmr) >
pehrhovey	0:a548a085de55	691	(pcb->keep_idle + pcb->keep_cnt_sent * TCP_KEEPINTVL_DEFAULT)
pehrhovey	0:a548a085de55	692	/ TCP_SLOW_INTERVAL)
pehrhovey	0:a548a085de55	693	#endif /* LWIP_TCP_KEEPALIVE */
pehrhovey	0:a548a085de55	694	{
pehrhovey	0:a548a085de55	695	tcp_keepalive(pcb);
pehrhovey	0:a548a085de55	696	pcb->keep_cnt_sent++;
pehrhovey	0:a548a085de55	697	}
pehrhovey	0:a548a085de55	698	}
pehrhovey	0:a548a085de55	699
pehrhovey	0:a548a085de55	700	/* If this PCB has queued out of sequence data, but has been
pehrhovey	0:a548a085de55	701	inactive for too long, will drop the data (it will eventually
pehrhovey	0:a548a085de55	702	be retransmitted). */
pehrhovey	0:a548a085de55	703	#if TCP_QUEUE_OOSEQ
pehrhovey	0:a548a085de55	704	if (pcb->ooseq != NULL &&
pehrhovey	0:a548a085de55	705	(u32_t)tcp_ticks - pcb->tmr >= pcb->rto * TCP_OOSEQ_TIMEOUT) {
pehrhovey	0:a548a085de55	706	tcp_segs_free(pcb->ooseq);
pehrhovey	0:a548a085de55	707	pcb->ooseq = NULL;
pehrhovey	0:a548a085de55	708	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: dropping OOSEQ queued data\n"));
pehrhovey	0:a548a085de55	709	}
pehrhovey	0:a548a085de55	710	#endif /* TCP_QUEUE_OOSEQ */
pehrhovey	0:a548a085de55	711
pehrhovey	0:a548a085de55	712	/* Check if this PCB has stayed too long in SYN-RCVD */
pehrhovey	0:a548a085de55	713	if (pcb->state == SYN_RCVD) {
pehrhovey	0:a548a085de55	714	if ((u32_t)(tcp_ticks - pcb->tmr) >
pehrhovey	0:a548a085de55	715	TCP_SYN_RCVD_TIMEOUT / TCP_SLOW_INTERVAL) {
pehrhovey	0:a548a085de55	716	++pcb_remove;
pehrhovey	0:a548a085de55	717	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in SYN-RCVD\n"));
pehrhovey	0:a548a085de55	718	}
pehrhovey	0:a548a085de55	719	}
pehrhovey	0:a548a085de55	720
pehrhovey	0:a548a085de55	721	/* Check if this PCB has stayed too long in LAST-ACK */
pehrhovey	0:a548a085de55	722	if (pcb->state == LAST_ACK) {
pehrhovey	0:a548a085de55	723	if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
pehrhovey	0:a548a085de55	724	++pcb_remove;
pehrhovey	0:a548a085de55	725	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in LAST-ACK\n"));
pehrhovey	0:a548a085de55	726	}
pehrhovey	0:a548a085de55	727	}
pehrhovey	0:a548a085de55	728
pehrhovey	0:a548a085de55	729	/* If the PCB should be removed, do it. */
pehrhovey	0:a548a085de55	730	if (pcb_remove) {
pehrhovey	0:a548a085de55	731	tcp_pcb_purge(pcb);
pehrhovey	0:a548a085de55	732	/* Remove PCB from tcp_active_pcbs list. */
pehrhovey	0:a548a085de55	733	if (prev != NULL) {
pehrhovey	0:a548a085de55	734	LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_active_pcbs", pcb != tcp_active_pcbs);
pehrhovey	0:a548a085de55	735	prev->next = pcb->next;
pehrhovey	0:a548a085de55	736	} else {
pehrhovey	0:a548a085de55	737	/* This PCB was the first. */
pehrhovey	0:a548a085de55	738	LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_active_pcbs", tcp_active_pcbs == pcb);
pehrhovey	0:a548a085de55	739	tcp_active_pcbs = pcb->next;
pehrhovey	0:a548a085de55	740	}
pehrhovey	0:a548a085de55	741
pehrhovey	0:a548a085de55	742	TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_ABRT);
pehrhovey	0:a548a085de55	743
pehrhovey	0:a548a085de55	744	pcb2 = pcb->next;
pehrhovey	0:a548a085de55	745	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	746	pcb = pcb2;
pehrhovey	0:a548a085de55	747	} else {
pehrhovey	0:a548a085de55	748
pehrhovey	0:a548a085de55	749	/* We check if we should poll the connection. */
pehrhovey	0:a548a085de55	750	++pcb->polltmr;
pehrhovey	0:a548a085de55	751	if (pcb->polltmr >= pcb->pollinterval) {
pehrhovey	0:a548a085de55	752	pcb->polltmr = 0;
pehrhovey	0:a548a085de55	753	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: polling application\n"));
pehrhovey	0:a548a085de55	754	TCP_EVENT_POLL(pcb, err);
pehrhovey	0:a548a085de55	755	if (err == ERR_OK) {
pehrhovey	0:a548a085de55	756	tcp_output(pcb);
pehrhovey	0:a548a085de55	757	}
pehrhovey	0:a548a085de55	758	}
pehrhovey	0:a548a085de55	759
pehrhovey	0:a548a085de55	760	prev = pcb;
pehrhovey	0:a548a085de55	761	pcb = pcb->next;
pehrhovey	0:a548a085de55	762	}
pehrhovey	0:a548a085de55	763	}
pehrhovey	0:a548a085de55	764
pehrhovey	0:a548a085de55	765
pehrhovey	0:a548a085de55	766	/* Steps through all of the TIME-WAIT PCBs. */
pehrhovey	0:a548a085de55	767	prev = NULL;
pehrhovey	0:a548a085de55	768	pcb = tcp_tw_pcbs;
pehrhovey	0:a548a085de55	769	while (pcb != NULL) {
pehrhovey	0:a548a085de55	770	LWIP_ASSERT("tcp_slowtmr: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
pehrhovey	0:a548a085de55	771	pcb_remove = 0;
pehrhovey	0:a548a085de55	772
pehrhovey	0:a548a085de55	773	/* Check if this PCB has stayed long enough in TIME-WAIT */
pehrhovey	0:a548a085de55	774	if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
pehrhovey	0:a548a085de55	775	++pcb_remove;
pehrhovey	0:a548a085de55	776	}
pehrhovey	0:a548a085de55	777
pehrhovey	0:a548a085de55	778
pehrhovey	0:a548a085de55	779
pehrhovey	0:a548a085de55	780	/* If the PCB should be removed, do it. */
pehrhovey	0:a548a085de55	781	if (pcb_remove) {
pehrhovey	0:a548a085de55	782	tcp_pcb_purge(pcb);
pehrhovey	0:a548a085de55	783	/* Remove PCB from tcp_tw_pcbs list. */
pehrhovey	0:a548a085de55	784	if (prev != NULL) {
pehrhovey	0:a548a085de55	785	LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_tw_pcbs", pcb != tcp_tw_pcbs);
pehrhovey	0:a548a085de55	786	prev->next = pcb->next;
pehrhovey	0:a548a085de55	787	} else {
pehrhovey	0:a548a085de55	788	/* This PCB was the first. */
pehrhovey	0:a548a085de55	789	LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_tw_pcbs", tcp_tw_pcbs == pcb);
pehrhovey	0:a548a085de55	790	tcp_tw_pcbs = pcb->next;
pehrhovey	0:a548a085de55	791	}
pehrhovey	0:a548a085de55	792	pcb2 = pcb->next;
pehrhovey	0:a548a085de55	793	memp_free(MEMP_TCP_PCB, pcb);
pehrhovey	0:a548a085de55	794	pcb = pcb2;
pehrhovey	0:a548a085de55	795	} else {
pehrhovey	0:a548a085de55	796	prev = pcb;
pehrhovey	0:a548a085de55	797	pcb = pcb->next;
pehrhovey	0:a548a085de55	798	}
pehrhovey	0:a548a085de55	799	}
pehrhovey	0:a548a085de55	800	}
pehrhovey	0:a548a085de55	801
pehrhovey	0:a548a085de55	802	/**
pehrhovey	0:a548a085de55	803	* Is called every TCP_FAST_INTERVAL (250 ms) and process data previously
pehrhovey	0:a548a085de55	804	* "refused" by upper layer (application) and sends delayed ACKs.
pehrhovey	0:a548a085de55	805	*
pehrhovey	0:a548a085de55	806	* Automatically called from tcp_tmr().
pehrhovey	0:a548a085de55	807	*/
pehrhovey	0:a548a085de55	808	void
pehrhovey	0:a548a085de55	809	tcp_fasttmr(void)
pehrhovey	0:a548a085de55	810	{
pehrhovey	0:a548a085de55	811	struct tcp_pcb *pcb;
pehrhovey	0:a548a085de55	812
pehrhovey	0:a548a085de55	813	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	814	/* If there is data which was previously "refused" by upper layer */
pehrhovey	0:a548a085de55	815	if (pcb->refused_data != NULL) {
pehrhovey	0:a548a085de55	816	/* Notify again application with data previously received. */
pehrhovey	0:a548a085de55	817	err_t err;
pehrhovey	0:a548a085de55	818	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_fasttmr: notify kept packet\n"));
pehrhovey	0:a548a085de55	819	TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
pehrhovey	0:a548a085de55	820	if (err == ERR_OK) {
pehrhovey	0:a548a085de55	821	pcb->refused_data = NULL;
pehrhovey	0:a548a085de55	822	}
pehrhovey	0:a548a085de55	823	}
pehrhovey	0:a548a085de55	824
pehrhovey	0:a548a085de55	825	/* send delayed ACKs */
pehrhovey	0:a548a085de55	826	if (pcb->flags & TF_ACK_DELAY) {
pehrhovey	0:a548a085de55	827	LWIP_DEBUGF(TCP_DEBUG, ("tcp_fasttmr: delayed ACK\n"));
pehrhovey	0:a548a085de55	828	tcp_ack_now(pcb);
pehrhovey	0:a548a085de55	829	pcb->flags &= ~(TF_ACK_DELAY \| TF_ACK_NOW);
pehrhovey	0:a548a085de55	830	}
pehrhovey	0:a548a085de55	831	}
pehrhovey	0:a548a085de55	832	}
pehrhovey	0:a548a085de55	833
pehrhovey	0:a548a085de55	834	/**
pehrhovey	0:a548a085de55	835	* Deallocates a list of TCP segments (tcp_seg structures).
pehrhovey	0:a548a085de55	836	*
pehrhovey	0:a548a085de55	837	* @param seg tcp_seg list of TCP segments to free
pehrhovey	0:a548a085de55	838	* @return the number of pbufs that were deallocated
pehrhovey	0:a548a085de55	839	*/
pehrhovey	0:a548a085de55	840	u8_t
pehrhovey	0:a548a085de55	841	tcp_segs_free(struct tcp_seg *seg)
pehrhovey	0:a548a085de55	842	{
pehrhovey	0:a548a085de55	843	u8_t count = 0;
pehrhovey	0:a548a085de55	844	struct tcp_seg *next;
pehrhovey	0:a548a085de55	845	while (seg != NULL) {
pehrhovey	0:a548a085de55	846	next = seg->next;
pehrhovey	0:a548a085de55	847	count += tcp_seg_free(seg);
pehrhovey	0:a548a085de55	848	seg = next;
pehrhovey	0:a548a085de55	849	}
pehrhovey	0:a548a085de55	850	return count;
pehrhovey	0:a548a085de55	851	}
pehrhovey	0:a548a085de55	852
pehrhovey	0:a548a085de55	853	/**
pehrhovey	0:a548a085de55	854	* Frees a TCP segment (tcp_seg structure).
pehrhovey	0:a548a085de55	855	*
pehrhovey	0:a548a085de55	856	* @param seg single tcp_seg to free
pehrhovey	0:a548a085de55	857	* @return the number of pbufs that were deallocated
pehrhovey	0:a548a085de55	858	*/
pehrhovey	0:a548a085de55	859	u8_t
pehrhovey	0:a548a085de55	860	tcp_seg_free(struct tcp_seg *seg)
pehrhovey	0:a548a085de55	861	{
pehrhovey	0:a548a085de55	862	u8_t count = 0;
pehrhovey	0:a548a085de55	863
pehrhovey	0:a548a085de55	864	if (seg != NULL) {
pehrhovey	0:a548a085de55	865	if (seg->p != NULL) {
pehrhovey	0:a548a085de55	866	count = pbuf_free(seg->p);
pehrhovey	0:a548a085de55	867	#if TCP_DEBUG
pehrhovey	0:a548a085de55	868	seg->p = NULL;
pehrhovey	0:a548a085de55	869	#endif /* TCP_DEBUG */
pehrhovey	0:a548a085de55	870	}
pehrhovey	0:a548a085de55	871	memp_free(MEMP_TCP_SEG, seg);
pehrhovey	0:a548a085de55	872	}
pehrhovey	0:a548a085de55	873	return count;
pehrhovey	0:a548a085de55	874	}
pehrhovey	0:a548a085de55	875
pehrhovey	0:a548a085de55	876	/**
pehrhovey	0:a548a085de55	877	* Sets the priority of a connection.
pehrhovey	0:a548a085de55	878	*
pehrhovey	0:a548a085de55	879	* @param pcb the tcp_pcb to manipulate
pehrhovey	0:a548a085de55	880	* @param prio new priority
pehrhovey	0:a548a085de55	881	*/
pehrhovey	0:a548a085de55	882	void
pehrhovey	0:a548a085de55	883	tcp_setprio(struct tcp_pcb *pcb, u8_t prio)
pehrhovey	0:a548a085de55	884	{
pehrhovey	0:a548a085de55	885	pcb->prio = prio;
pehrhovey	0:a548a085de55	886	}
pehrhovey	0:a548a085de55	887	#if TCP_QUEUE_OOSEQ
pehrhovey	0:a548a085de55	888
pehrhovey	0:a548a085de55	889	/**
pehrhovey	0:a548a085de55	890	* Returns a copy of the given TCP segment.
pehrhovey	0:a548a085de55	891	* The pbuf and data are not copied, only the pointers
pehrhovey	0:a548a085de55	892	*
pehrhovey	0:a548a085de55	893	* @param seg the old tcp_seg
pehrhovey	0:a548a085de55	894	* @return a copy of seg
pehrhovey	0:a548a085de55	895	*/
pehrhovey	0:a548a085de55	896	struct tcp_seg *
pehrhovey	0:a548a085de55	897	tcp_seg_copy(struct tcp_seg *seg)
pehrhovey	0:a548a085de55	898	{
pehrhovey	0:a548a085de55	899	struct tcp_seg *cseg;
pehrhovey	0:a548a085de55	900
pehrhovey	0:a548a085de55	901	cseg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG);
pehrhovey	0:a548a085de55	902	if (cseg == NULL) {
pehrhovey	0:a548a085de55	903	return NULL;
pehrhovey	0:a548a085de55	904	}
pehrhovey	0:a548a085de55	905	SMEMCPY((u8_t )cseg, (const u8_t )seg, sizeof(struct tcp_seg));
pehrhovey	0:a548a085de55	906	pbuf_ref(cseg->p);
pehrhovey	0:a548a085de55	907	return cseg;
pehrhovey	0:a548a085de55	908	}
pehrhovey	0:a548a085de55	909	#endif
pehrhovey	0:a548a085de55	910
pehrhovey	0:a548a085de55	911	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	912	/**
pehrhovey	0:a548a085de55	913	* Default receive callback that is called if the user didn't register
pehrhovey	0:a548a085de55	914	* a recv callback for the pcb.
pehrhovey	0:a548a085de55	915	*/
pehrhovey	0:a548a085de55	916	static err_t
pehrhovey	0:a548a085de55	917	tcp_recv_null(void arg, struct tcp_pcb pcb, struct pbuf *p, err_t err)
pehrhovey	0:a548a085de55	918	{
pehrhovey	0:a548a085de55	919	arg = arg;
pehrhovey	0:a548a085de55	920	if (p != NULL) {
pehrhovey	0:a548a085de55	921	pbuf_free(p);
pehrhovey	0:a548a085de55	922	} else if (err == ERR_OK) {
pehrhovey	0:a548a085de55	923	return tcp_close(pcb);
pehrhovey	0:a548a085de55	924	}
pehrhovey	0:a548a085de55	925	return ERR_OK;
pehrhovey	0:a548a085de55	926	}
pehrhovey	0:a548a085de55	927	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	928
pehrhovey	0:a548a085de55	929	/**
pehrhovey	0:a548a085de55	930	* Kills the oldest active connection that has lower priority than prio.
pehrhovey	0:a548a085de55	931	*
pehrhovey	0:a548a085de55	932	* @param prio minimum priority
pehrhovey	0:a548a085de55	933	*/
pehrhovey	0:a548a085de55	934	static void
pehrhovey	0:a548a085de55	935	tcp_kill_prio(u8_t prio)
pehrhovey	0:a548a085de55	936	{
pehrhovey	0:a548a085de55	937	struct tcp_pcb pcb, inactive;
pehrhovey	0:a548a085de55	938	u32_t inactivity;
pehrhovey	0:a548a085de55	939	u8_t mprio;
pehrhovey	0:a548a085de55	940
pehrhovey	0:a548a085de55	941
pehrhovey	0:a548a085de55	942	mprio = TCP_PRIO_MAX;
pehrhovey	0:a548a085de55	943
pehrhovey	0:a548a085de55	944	/* We kill the oldest active connection that has lower priority than prio. */
pehrhovey	0:a548a085de55	945	inactivity = 0;
pehrhovey	0:a548a085de55	946	inactive = NULL;
pehrhovey	0:a548a085de55	947	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	948	if (pcb->prio <= prio &&
pehrhovey	0:a548a085de55	949	pcb->prio <= mprio &&
pehrhovey	0:a548a085de55	950	(u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
pehrhovey	0:a548a085de55	951	inactivity = tcp_ticks - pcb->tmr;
pehrhovey	0:a548a085de55	952	inactive = pcb;
pehrhovey	0:a548a085de55	953	mprio = pcb->prio;
pehrhovey	0:a548a085de55	954	}
pehrhovey	0:a548a085de55	955	}
pehrhovey	0:a548a085de55	956	if (inactive != NULL) {
pehrhovey	0:a548a085de55	957	LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_prio: killing oldest PCB %p (%"S32_F")\n",
pehrhovey	0:a548a085de55	958	(void *)inactive, inactivity));
pehrhovey	0:a548a085de55	959	tcp_abort(inactive);
pehrhovey	0:a548a085de55	960	}
pehrhovey	0:a548a085de55	961	}
pehrhovey	0:a548a085de55	962
pehrhovey	0:a548a085de55	963	/**
pehrhovey	0:a548a085de55	964	* Kills the oldest connection that is in TIME_WAIT state.
pehrhovey	0:a548a085de55	965	* Called from tcp_alloc() if no more connections are available.
pehrhovey	0:a548a085de55	966	*/
pehrhovey	0:a548a085de55	967	static void
pehrhovey	0:a548a085de55	968	tcp_kill_timewait(void)
pehrhovey	0:a548a085de55	969	{
pehrhovey	0:a548a085de55	970	struct tcp_pcb pcb, inactive;
pehrhovey	0:a548a085de55	971	u32_t inactivity;
pehrhovey	0:a548a085de55	972
pehrhovey	0:a548a085de55	973	inactivity = 0;
pehrhovey	0:a548a085de55	974	inactive = NULL;
pehrhovey	0:a548a085de55	975	/* Go through the list of TIME_WAIT pcbs and get the oldest pcb. */
pehrhovey	0:a548a085de55	976	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	977	if ((u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
pehrhovey	0:a548a085de55	978	inactivity = tcp_ticks - pcb->tmr;
pehrhovey	0:a548a085de55	979	inactive = pcb;
pehrhovey	0:a548a085de55	980	}
pehrhovey	0:a548a085de55	981	}
pehrhovey	0:a548a085de55	982	if (inactive != NULL) {
pehrhovey	0:a548a085de55	983	LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_timewait: killing oldest TIME-WAIT PCB %p (%"S32_F")\n",
pehrhovey	0:a548a085de55	984	(void *)inactive, inactivity));
pehrhovey	0:a548a085de55	985	tcp_abort(inactive);
pehrhovey	0:a548a085de55	986	}
pehrhovey	0:a548a085de55	987	}
pehrhovey	0:a548a085de55	988
pehrhovey	0:a548a085de55	989	/**
pehrhovey	0:a548a085de55	990	* Allocate a new tcp_pcb structure.
pehrhovey	0:a548a085de55	991	*
pehrhovey	0:a548a085de55	992	* @param prio priority for the new pcb
pehrhovey	0:a548a085de55	993	* @return a new tcp_pcb that initially is in state CLOSED
pehrhovey	0:a548a085de55	994	*/
pehrhovey	0:a548a085de55	995	struct tcp_pcb *
pehrhovey	0:a548a085de55	996	tcp_alloc(u8_t prio)
pehrhovey	0:a548a085de55	997	{
pehrhovey	0:a548a085de55	998	struct tcp_pcb *pcb;
pehrhovey	0:a548a085de55	999	u32_t iss;
pehrhovey	0:a548a085de55	1000
pehrhovey	0:a548a085de55	1001	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
pehrhovey	0:a548a085de55	1002	if (pcb == NULL) {
pehrhovey	0:a548a085de55	1003	/* Try killing oldest connection in TIME-WAIT. */
pehrhovey	0:a548a085de55	1004	LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing off oldest TIME-WAIT connection\n"));
pehrhovey	0:a548a085de55	1005	tcp_kill_timewait();
pehrhovey	0:a548a085de55	1006	/* Try to allocate a tcp_pcb again. */
pehrhovey	0:a548a085de55	1007	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
pehrhovey	0:a548a085de55	1008	if (pcb == NULL) {
pehrhovey	0:a548a085de55	1009	/* Try killing active connections with lower priority than the new one. */
pehrhovey	0:a548a085de55	1010	tcp_kill_prio(prio);
pehrhovey	0:a548a085de55	1011	/* Try to allocate a tcp_pcb again. */
pehrhovey	0:a548a085de55	1012	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
pehrhovey	0:a548a085de55	1013	}
pehrhovey	0:a548a085de55	1014	}
pehrhovey	0:a548a085de55	1015	if (pcb != NULL) {
pehrhovey	0:a548a085de55	1016	memset(pcb, 0, sizeof(struct tcp_pcb));
pehrhovey	0:a548a085de55	1017	pcb->prio = TCP_PRIO_NORMAL;
pehrhovey	0:a548a085de55	1018	pcb->snd_buf = TCP_SND_BUF;
pehrhovey	0:a548a085de55	1019	pcb->snd_queuelen = 0;
pehrhovey	0:a548a085de55	1020	pcb->rcv_wnd = TCP_WND;
pehrhovey	0:a548a085de55	1021	pcb->rcv_ann_wnd = TCP_WND;
pehrhovey	0:a548a085de55	1022	pcb->tos = 0;
pehrhovey	0:a548a085de55	1023	pcb->ttl = TCP_TTL;
pehrhovey	0:a548a085de55	1024	/* As initial send MSS, we use TCP_MSS but limit it to 536.
pehrhovey	0:a548a085de55	1025	The send MSS is updated when an MSS option is received. */
pehrhovey	0:a548a085de55	1026	pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
pehrhovey	0:a548a085de55	1027	pcb->rto = 3000 / TCP_SLOW_INTERVAL;
pehrhovey	0:a548a085de55	1028	pcb->sa = 0;
pehrhovey	0:a548a085de55	1029	pcb->sv = 3000 / TCP_SLOW_INTERVAL;
pehrhovey	0:a548a085de55	1030	pcb->rtime = -1;
pehrhovey	0:a548a085de55	1031	pcb->cwnd = 1;
pehrhovey	0:a548a085de55	1032	iss = tcp_next_iss();
pehrhovey	0:a548a085de55	1033	pcb->snd_wl2 = iss;
pehrhovey	0:a548a085de55	1034	pcb->snd_nxt = iss;
pehrhovey	0:a548a085de55	1035	pcb->lastack = iss;
pehrhovey	0:a548a085de55	1036	pcb->snd_lbb = iss;
pehrhovey	0:a548a085de55	1037	pcb->tmr = tcp_ticks;
pehrhovey	0:a548a085de55	1038
pehrhovey	0:a548a085de55	1039	pcb->polltmr = 0;
pehrhovey	0:a548a085de55	1040
pehrhovey	0:a548a085de55	1041	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	1042	pcb->recv = tcp_recv_null;
pehrhovey	0:a548a085de55	1043	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	1044
pehrhovey	0:a548a085de55	1045	/* Init KEEPALIVE timer */
pehrhovey	0:a548a085de55	1046	pcb->keep_idle = TCP_KEEPIDLE_DEFAULT;
pehrhovey	0:a548a085de55	1047
pehrhovey	0:a548a085de55	1048	#if LWIP_TCP_KEEPALIVE
pehrhovey	0:a548a085de55	1049	pcb->keep_intvl = TCP_KEEPINTVL_DEFAULT;
pehrhovey	0:a548a085de55	1050	pcb->keep_cnt = TCP_KEEPCNT_DEFAULT;
pehrhovey	0:a548a085de55	1051	#endif /* LWIP_TCP_KEEPALIVE */
pehrhovey	0:a548a085de55	1052
pehrhovey	0:a548a085de55	1053	pcb->keep_cnt_sent = 0;
pehrhovey	0:a548a085de55	1054	}
pehrhovey	0:a548a085de55	1055	return pcb;
pehrhovey	0:a548a085de55	1056	}
pehrhovey	0:a548a085de55	1057
pehrhovey	0:a548a085de55	1058	/**
pehrhovey	0:a548a085de55	1059	* Creates a new TCP protocol control block but doesn't place it on
pehrhovey	0:a548a085de55	1060	* any of the TCP PCB lists.
pehrhovey	0:a548a085de55	1061	* The pcb is not put on any list until binding using tcp_bind().
pehrhovey	0:a548a085de55	1062	*
pehrhovey	0:a548a085de55	1063	* @internal: Maybe there should be a idle TCP PCB list where these
pehrhovey	0:a548a085de55	1064	* PCBs are put on. Port reservation using tcp_bind() is implemented but
pehrhovey	0:a548a085de55	1065	* allocated pcbs that are not bound can't be killed automatically if wanting
pehrhovey	0:a548a085de55	1066	* to allocate a pcb with higher prio (@see tcp_kill_prio())
pehrhovey	0:a548a085de55	1067	*
pehrhovey	0:a548a085de55	1068	* @return a new tcp_pcb that initially is in state CLOSED
pehrhovey	0:a548a085de55	1069	*/
pehrhovey	0:a548a085de55	1070	struct tcp_pcb *
pehrhovey	0:a548a085de55	1071	tcp_new(void)
pehrhovey	0:a548a085de55	1072	{
pehrhovey	0:a548a085de55	1073	return tcp_alloc(TCP_PRIO_NORMAL);
pehrhovey	0:a548a085de55	1074	}
pehrhovey	0:a548a085de55	1075
pehrhovey	0:a548a085de55	1076	/**
pehrhovey	0:a548a085de55	1077	* Used to specify the argument that should be passed callback
pehrhovey	0:a548a085de55	1078	* functions.
pehrhovey	0:a548a085de55	1079	*
pehrhovey	0:a548a085de55	1080	* @param pcb tcp_pcb to set the callback argument
pehrhovey	0:a548a085de55	1081	* @param arg void pointer argument to pass to callback functions
pehrhovey	0:a548a085de55	1082	*/
pehrhovey	0:a548a085de55	1083	void
pehrhovey	0:a548a085de55	1084	tcp_arg(struct tcp_pcb pcb, void arg)
pehrhovey	0:a548a085de55	1085	{
pehrhovey	0:a548a085de55	1086	pcb->callback_arg = arg;
pehrhovey	0:a548a085de55	1087	}
pehrhovey	0:a548a085de55	1088	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	1089
pehrhovey	0:a548a085de55	1090	/**
pehrhovey	0:a548a085de55	1091	* Used to specify the function that should be called when a TCP
pehrhovey	0:a548a085de55	1092	* connection receives data.
pehrhovey	0:a548a085de55	1093	*
pehrhovey	0:a548a085de55	1094	* @param pcb tcp_pcb to set the recv callback
pehrhovey	0:a548a085de55	1095	* @param recv callback function to call for this pcb when data is received
pehrhovey	0:a548a085de55	1096	*/
pehrhovey	0:a548a085de55	1097	void
pehrhovey	0:a548a085de55	1098	tcp_recv(struct tcp_pcb *pcb,
pehrhovey	0:a548a085de55	1099	err_t (* recv)(void arg, struct tcp_pcb tpcb, struct pbuf *p, err_t err))
pehrhovey	0:a548a085de55	1100	{
pehrhovey	0:a548a085de55	1101	pcb->recv = recv;
pehrhovey	0:a548a085de55	1102	}
pehrhovey	0:a548a085de55	1103
pehrhovey	0:a548a085de55	1104	/**
pehrhovey	0:a548a085de55	1105	* Used to specify the function that should be called when TCP data
pehrhovey	0:a548a085de55	1106	* has been successfully delivered to the remote host.
pehrhovey	0:a548a085de55	1107	*
pehrhovey	0:a548a085de55	1108	* @param pcb tcp_pcb to set the sent callback
pehrhovey	0:a548a085de55	1109	* @param sent callback function to call for this pcb when data is successfully sent
pehrhovey	0:a548a085de55	1110	*/
pehrhovey	0:a548a085de55	1111	void
pehrhovey	0:a548a085de55	1112	tcp_sent(struct tcp_pcb *pcb,
pehrhovey	0:a548a085de55	1113	err_t (* sent)(void arg, struct tcp_pcb tpcb, u16_t len))
pehrhovey	0:a548a085de55	1114	{
pehrhovey	0:a548a085de55	1115	pcb->sent = sent;
pehrhovey	0:a548a085de55	1116	}
pehrhovey	0:a548a085de55	1117
pehrhovey	0:a548a085de55	1118	/**
pehrhovey	0:a548a085de55	1119	* Used to specify the function that should be called when a fatal error
pehrhovey	0:a548a085de55	1120	* has occured on the connection.
pehrhovey	0:a548a085de55	1121	*
pehrhovey	0:a548a085de55	1122	* @param pcb tcp_pcb to set the err callback
pehrhovey	0:a548a085de55	1123	* @param errf callback function to call for this pcb when a fatal error
pehrhovey	0:a548a085de55	1124	* has occured on the connection
pehrhovey	0:a548a085de55	1125	*/
pehrhovey	0:a548a085de55	1126	void
pehrhovey	0:a548a085de55	1127	tcp_err(struct tcp_pcb *pcb,
pehrhovey	0:a548a085de55	1128	void (* errf)(void *arg, err_t err))
pehrhovey	0:a548a085de55	1129	{
pehrhovey	0:a548a085de55	1130	pcb->errf = errf;
pehrhovey	0:a548a085de55	1131	}
pehrhovey	0:a548a085de55	1132
pehrhovey	0:a548a085de55	1133	/**
pehrhovey	0:a548a085de55	1134	* Used for specifying the function that should be called when a
pehrhovey	0:a548a085de55	1135	* LISTENing connection has been connected to another host.
pehrhovey	0:a548a085de55	1136	*
pehrhovey	0:a548a085de55	1137	* @param pcb tcp_pcb to set the accept callback
pehrhovey	0:a548a085de55	1138	* @param accept callback function to call for this pcb when LISTENing
pehrhovey	0:a548a085de55	1139	* connection has been connected to another host
pehrhovey	0:a548a085de55	1140	*/
pehrhovey	0:a548a085de55	1141	void
pehrhovey	0:a548a085de55	1142	tcp_accept(struct tcp_pcb *pcb,
pehrhovey	0:a548a085de55	1143	err_t (* accept)(void arg, struct tcp_pcb newpcb, err_t err))
pehrhovey	0:a548a085de55	1144	{
pehrhovey	0:a548a085de55	1145	pcb->accept = accept;
pehrhovey	0:a548a085de55	1146	}
pehrhovey	0:a548a085de55	1147	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	1148
pehrhovey	0:a548a085de55	1149
pehrhovey	0:a548a085de55	1150	/**
pehrhovey	0:a548a085de55	1151	* Used to specify the function that should be called periodically
pehrhovey	0:a548a085de55	1152	* from TCP. The interval is specified in terms of the TCP coarse
pehrhovey	0:a548a085de55	1153	* timer interval, which is called twice a second.
pehrhovey	0:a548a085de55	1154	*
pehrhovey	0:a548a085de55	1155	*/
pehrhovey	0:a548a085de55	1156	void
pehrhovey	0:a548a085de55	1157	tcp_poll(struct tcp_pcb *pcb,
pehrhovey	0:a548a085de55	1158	err_t (* poll)(void arg, struct tcp_pcb tpcb), u8_t interval)
pehrhovey	0:a548a085de55	1159	{
pehrhovey	0:a548a085de55	1160	#if LWIP_CALLBACK_API
pehrhovey	0:a548a085de55	1161	pcb->poll = poll;
pehrhovey	0:a548a085de55	1162	#endif /* LWIP_CALLBACK_API */
pehrhovey	0:a548a085de55	1163	pcb->pollinterval = interval;
pehrhovey	0:a548a085de55	1164	}
pehrhovey	0:a548a085de55	1165
pehrhovey	0:a548a085de55	1166	/**
pehrhovey	0:a548a085de55	1167	* Purges a TCP PCB. Removes any buffered data and frees the buffer memory
pehrhovey	0:a548a085de55	1168	* (pcb->ooseq, pcb->unsent and pcb->unacked are freed).
pehrhovey	0:a548a085de55	1169	*
pehrhovey	0:a548a085de55	1170	* @param pcb tcp_pcb to purge. The pcb itself is not deallocated!
pehrhovey	0:a548a085de55	1171	*/
pehrhovey	0:a548a085de55	1172	void
pehrhovey	0:a548a085de55	1173	tcp_pcb_purge(struct tcp_pcb *pcb)
pehrhovey	0:a548a085de55	1174	{
pehrhovey	0:a548a085de55	1175	if (pcb->state != CLOSED &&
pehrhovey	0:a548a085de55	1176	pcb->state != TIME_WAIT &&
pehrhovey	0:a548a085de55	1177	pcb->state != LISTEN) {
pehrhovey	0:a548a085de55	1178
pehrhovey	0:a548a085de55	1179	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge\n"));
pehrhovey	0:a548a085de55	1180
pehrhovey	0:a548a085de55	1181	#if TCP_LISTEN_BACKLOG
pehrhovey	0:a548a085de55	1182	if (pcb->state == SYN_RCVD) {
pehrhovey	0:a548a085de55	1183	/* Need to find the corresponding listen_pcb and decrease its accepts_pending */
pehrhovey	0:a548a085de55	1184	struct tcp_pcb_listen *lpcb;
pehrhovey	0:a548a085de55	1185	LWIP_ASSERT("tcp_pcb_purge: pcb->state == SYN_RCVD but tcp_listen_pcbs is NULL",
pehrhovey	0:a548a085de55	1186	tcp_listen_pcbs.listen_pcbs != NULL);
pehrhovey	0:a548a085de55	1187	for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
pehrhovey	0:a548a085de55	1188	if ((lpcb->local_port == pcb->local_port) &&
pehrhovey	0:a548a085de55	1189	(ip_addr_isany(&lpcb->local_ip) \|\|
pehrhovey	0:a548a085de55	1190	ip_addr_cmp(&pcb->local_ip, &lpcb->local_ip))) {
pehrhovey	0:a548a085de55	1191	/* port and address of the listen pcb match the timed-out pcb */
pehrhovey	0:a548a085de55	1192	LWIP_ASSERT("tcp_pcb_purge: listen pcb does not have accepts pending",
pehrhovey	0:a548a085de55	1193	lpcb->accepts_pending > 0);
pehrhovey	0:a548a085de55	1194	lpcb->accepts_pending--;
pehrhovey	0:a548a085de55	1195	break;
pehrhovey	0:a548a085de55	1196	}
pehrhovey	0:a548a085de55	1197	}
pehrhovey	0:a548a085de55	1198	}
pehrhovey	0:a548a085de55	1199	#endif /* TCP_LISTEN_BACKLOG */
pehrhovey	0:a548a085de55	1200
pehrhovey	0:a548a085de55	1201
pehrhovey	0:a548a085de55	1202	if (pcb->refused_data != NULL) {
pehrhovey	0:a548a085de55	1203	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->refused_data\n"));
pehrhovey	0:a548a085de55	1204	pbuf_free(pcb->refused_data);
pehrhovey	0:a548a085de55	1205	pcb->refused_data = NULL;
pehrhovey	0:a548a085de55	1206	}
pehrhovey	0:a548a085de55	1207	if (pcb->unsent != NULL) {
pehrhovey	0:a548a085de55	1208	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: not all data sent\n"));
pehrhovey	0:a548a085de55	1209	}
pehrhovey	0:a548a085de55	1210	if (pcb->unacked != NULL) {
pehrhovey	0:a548a085de55	1211	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->unacked\n"));
pehrhovey	0:a548a085de55	1212	}
pehrhovey	0:a548a085de55	1213	#if TCP_QUEUE_OOSEQ /* LW */
pehrhovey	0:a548a085de55	1214	if (pcb->ooseq != NULL) {
pehrhovey	0:a548a085de55	1215	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->ooseq\n"));
pehrhovey	0:a548a085de55	1216	}
pehrhovey	0:a548a085de55	1217
pehrhovey	0:a548a085de55	1218	/* Stop the retransmission timer as it will expect data on unacked
pehrhovey	0:a548a085de55	1219	queue if it fires */
pehrhovey	0:a548a085de55	1220	pcb->rtime = -1;
pehrhovey	0:a548a085de55	1221
pehrhovey	0:a548a085de55	1222	tcp_segs_free(pcb->ooseq);
pehrhovey	0:a548a085de55	1223	pcb->ooseq = NULL;
pehrhovey	0:a548a085de55	1224	#endif /* TCP_QUEUE_OOSEQ */
pehrhovey	0:a548a085de55	1225	tcp_segs_free(pcb->unsent);
pehrhovey	0:a548a085de55	1226	tcp_segs_free(pcb->unacked);
pehrhovey	0:a548a085de55	1227	pcb->unacked = pcb->unsent = NULL;
pehrhovey	0:a548a085de55	1228	}
pehrhovey	0:a548a085de55	1229	}
pehrhovey	0:a548a085de55	1230
pehrhovey	0:a548a085de55	1231	/**
pehrhovey	0:a548a085de55	1232	* Purges the PCB and removes it from a PCB list. Any delayed ACKs are sent first.
pehrhovey	0:a548a085de55	1233	*
pehrhovey	0:a548a085de55	1234	* @param pcblist PCB list to purge.
pehrhovey	0:a548a085de55	1235	* @param pcb tcp_pcb to purge. The pcb itself is also deallocated!
pehrhovey	0:a548a085de55	1236	*/
pehrhovey	0:a548a085de55	1237	void
pehrhovey	0:a548a085de55	1238	tcp_pcb_remove(struct tcp_pcb *pcblist, struct tcp_pcb pcb)
pehrhovey	0:a548a085de55	1239	{
pehrhovey	0:a548a085de55	1240	TCP_RMV(pcblist, pcb);
pehrhovey	0:a548a085de55	1241
pehrhovey	0:a548a085de55	1242	tcp_pcb_purge(pcb);
pehrhovey	0:a548a085de55	1243
pehrhovey	0:a548a085de55	1244	/* if there is an outstanding delayed ACKs, send it */
pehrhovey	0:a548a085de55	1245	if (pcb->state != TIME_WAIT &&
pehrhovey	0:a548a085de55	1246	pcb->state != LISTEN &&
pehrhovey	0:a548a085de55	1247	pcb->flags & TF_ACK_DELAY) {
pehrhovey	0:a548a085de55	1248	pcb->flags \|= TF_ACK_NOW;
pehrhovey	0:a548a085de55	1249	tcp_output(pcb);
pehrhovey	0:a548a085de55	1250	}
pehrhovey	0:a548a085de55	1251
pehrhovey	0:a548a085de55	1252	if (pcb->state != LISTEN) {
pehrhovey	0:a548a085de55	1253	LWIP_ASSERT("unsent segments leaking", pcb->unsent == NULL);
pehrhovey	0:a548a085de55	1254	LWIP_ASSERT("unacked segments leaking", pcb->unacked == NULL);
pehrhovey	0:a548a085de55	1255	#if TCP_QUEUE_OOSEQ
pehrhovey	0:a548a085de55	1256	LWIP_ASSERT("ooseq segments leaking", pcb->ooseq == NULL);
pehrhovey	0:a548a085de55	1257	#endif /* TCP_QUEUE_OOSEQ */
pehrhovey	0:a548a085de55	1258	}
pehrhovey	0:a548a085de55	1259
pehrhovey	0:a548a085de55	1260	pcb->state = CLOSED;
pehrhovey	0:a548a085de55	1261
pehrhovey	0:a548a085de55	1262	LWIP_ASSERT("tcp_pcb_remove: tcp_pcbs_sane()", tcp_pcbs_sane());
pehrhovey	0:a548a085de55	1263	}
pehrhovey	0:a548a085de55	1264
pehrhovey	0:a548a085de55	1265	/**
pehrhovey	0:a548a085de55	1266	* Calculates a new initial sequence number for new connections.
pehrhovey	0:a548a085de55	1267	*
pehrhovey	0:a548a085de55	1268	* @return u32_t pseudo random sequence number
pehrhovey	0:a548a085de55	1269	*/
pehrhovey	0:a548a085de55	1270	u32_t
pehrhovey	0:a548a085de55	1271	tcp_next_iss(void)
pehrhovey	0:a548a085de55	1272	{
pehrhovey	0:a548a085de55	1273	static u32_t iss = 6510;
pehrhovey	0:a548a085de55	1274
pehrhovey	0:a548a085de55	1275	iss += tcp_ticks; /* XXX */
pehrhovey	0:a548a085de55	1276	return iss;
pehrhovey	0:a548a085de55	1277	}
pehrhovey	0:a548a085de55	1278
pehrhovey	0:a548a085de55	1279	#if TCP_CALCULATE_EFF_SEND_MSS
pehrhovey	0:a548a085de55	1280	/**
pehrhovey	0:a548a085de55	1281	* Calcluates the effective send mss that can be used for a specific IP address
pehrhovey	0:a548a085de55	1282	* by using ip_route to determin the netif used to send to the address and
pehrhovey	0:a548a085de55	1283	* calculating the minimum of TCP_MSS and that netif's mtu (if set).
pehrhovey	0:a548a085de55	1284	*/
pehrhovey	0:a548a085de55	1285	u16_t
pehrhovey	0:a548a085de55	1286	tcp_eff_send_mss(u16_t sendmss, struct ip_addr *addr)
pehrhovey	0:a548a085de55	1287	{
pehrhovey	0:a548a085de55	1288	u16_t mss_s;
pehrhovey	0:a548a085de55	1289	struct netif *outif;
pehrhovey	0:a548a085de55	1290
pehrhovey	0:a548a085de55	1291	outif = ip_route(addr);
pehrhovey	0:a548a085de55	1292	if ((outif != NULL) && (outif->mtu != 0)) {
pehrhovey	0:a548a085de55	1293	mss_s = outif->mtu - IP_HLEN - TCP_HLEN;
pehrhovey	0:a548a085de55	1294	/* RFC 1122, chap 4.2.2.6:
pehrhovey	0:a548a085de55	1295	* Eff.snd.MSS = min(SendMSS+20, MMS_S) - TCPhdrsize - IPoptionsize
pehrhovey	0:a548a085de55	1296	* We correct for TCP options in tcp_enqueue(), and don't support
pehrhovey	0:a548a085de55	1297	* IP options
pehrhovey	0:a548a085de55	1298	*/
pehrhovey	0:a548a085de55	1299	sendmss = LWIP_MIN(sendmss, mss_s);
pehrhovey	0:a548a085de55	1300	}
pehrhovey	0:a548a085de55	1301	return sendmss;
pehrhovey	0:a548a085de55	1302	}
pehrhovey	0:a548a085de55	1303	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
pehrhovey	0:a548a085de55	1304
pehrhovey	0:a548a085de55	1305	const char*
pehrhovey	0:a548a085de55	1306	tcp_debug_state_str(enum tcp_state s)
pehrhovey	0:a548a085de55	1307	{
pehrhovey	0:a548a085de55	1308	return tcp_state_str[s];
pehrhovey	0:a548a085de55	1309	}
pehrhovey	0:a548a085de55	1310
pehrhovey	0:a548a085de55	1311	#if TCP_DEBUG \|\| TCP_INPUT_DEBUG \|\| TCP_OUTPUT_DEBUG
pehrhovey	0:a548a085de55	1312	/**
pehrhovey	0:a548a085de55	1313	* Print a tcp header for debugging purposes.
pehrhovey	0:a548a085de55	1314	*
pehrhovey	0:a548a085de55	1315	* @param tcphdr pointer to a struct tcp_hdr
pehrhovey	0:a548a085de55	1316	*/
pehrhovey	0:a548a085de55	1317	void
pehrhovey	0:a548a085de55	1318	tcp_debug_print(struct tcp_hdr *tcphdr)
pehrhovey	0:a548a085de55	1319	{
pehrhovey	0:a548a085de55	1320	LWIP_DEBUGF(TCP_DEBUG, ("TCP header:\n"));
pehrhovey	0:a548a085de55	1321	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
pehrhovey	0:a548a085de55	1322	LWIP_DEBUGF(TCP_DEBUG, ("\| %5"U16_F" \| %5"U16_F" \| (src port, dest port)\n",
pehrhovey	0:a548a085de55	1323	ntohs(tcphdr->src), ntohs(tcphdr->dest)));
pehrhovey	0:a548a085de55	1324	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
pehrhovey	0:a548a085de55	1325	LWIP_DEBUGF(TCP_DEBUG, ("\| %010"U32_F" \| (seq no)\n",
pehrhovey	0:a548a085de55	1326	ntohl(tcphdr->seqno)));
pehrhovey	0:a548a085de55	1327	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
pehrhovey	0:a548a085de55	1328	LWIP_DEBUGF(TCP_DEBUG, ("\| %010"U32_F" \| (ack no)\n",
pehrhovey	0:a548a085de55	1329	ntohl(tcphdr->ackno)));
pehrhovey	0:a548a085de55	1330	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
pehrhovey	0:a548a085de55	1331	LWIP_DEBUGF(TCP_DEBUG, ("\| %2"U16_F" \| \|%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"\| %5"U16_F" \| (hdrlen, flags (",
pehrhovey	0:a548a085de55	1332	TCPH_HDRLEN(tcphdr),
pehrhovey	0:a548a085de55	1333	TCPH_FLAGS(tcphdr) >> 5 & 1,
pehrhovey	0:a548a085de55	1334	TCPH_FLAGS(tcphdr) >> 4 & 1,
pehrhovey	0:a548a085de55	1335	TCPH_FLAGS(tcphdr) >> 3 & 1,
pehrhovey	0:a548a085de55	1336	TCPH_FLAGS(tcphdr) >> 2 & 1,
pehrhovey	0:a548a085de55	1337	TCPH_FLAGS(tcphdr) >> 1 & 1,
pehrhovey	0:a548a085de55	1338	TCPH_FLAGS(tcphdr) & 1,
pehrhovey	0:a548a085de55	1339	ntohs(tcphdr->wnd)));
pehrhovey	0:a548a085de55	1340	tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
pehrhovey	0:a548a085de55	1341	LWIP_DEBUGF(TCP_DEBUG, ("), win)\n"));
pehrhovey	0:a548a085de55	1342	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
pehrhovey	0:a548a085de55	1343	LWIP_DEBUGF(TCP_DEBUG, ("\| 0x%04"X16_F" \| %5"U16_F" \| (chksum, urgp)\n",
pehrhovey	0:a548a085de55	1344	ntohs(tcphdr->chksum), ntohs(tcphdr->urgp)));
pehrhovey	0:a548a085de55	1345	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
pehrhovey	0:a548a085de55	1346	}
pehrhovey	0:a548a085de55	1347
pehrhovey	0:a548a085de55	1348	/**
pehrhovey	0:a548a085de55	1349	* Print a tcp state for debugging purposes.
pehrhovey	0:a548a085de55	1350	*
pehrhovey	0:a548a085de55	1351	* @param s enum tcp_state to print
pehrhovey	0:a548a085de55	1352	*/
pehrhovey	0:a548a085de55	1353	void
pehrhovey	0:a548a085de55	1354	tcp_debug_print_state(enum tcp_state s)
pehrhovey	0:a548a085de55	1355	{
pehrhovey	0:a548a085de55	1356	LWIP_DEBUGF(TCP_DEBUG, ("State: %s\n", tcp_state_str[s]));
pehrhovey	0:a548a085de55	1357	}
pehrhovey	0:a548a085de55	1358
pehrhovey	0:a548a085de55	1359	/**
pehrhovey	0:a548a085de55	1360	* Print tcp flags for debugging purposes.
pehrhovey	0:a548a085de55	1361	*
pehrhovey	0:a548a085de55	1362	* @param flags tcp flags, all active flags are printed
pehrhovey	0:a548a085de55	1363	*/
pehrhovey	0:a548a085de55	1364	void
pehrhovey	0:a548a085de55	1365	tcp_debug_print_flags(u8_t flags)
pehrhovey	0:a548a085de55	1366	{
pehrhovey	0:a548a085de55	1367	if (flags & TCP_FIN) {
pehrhovey	0:a548a085de55	1368	LWIP_DEBUGF(TCP_DEBUG, ("FIN "));
pehrhovey	0:a548a085de55	1369	}
pehrhovey	0:a548a085de55	1370	if (flags & TCP_SYN) {
pehrhovey	0:a548a085de55	1371	LWIP_DEBUGF(TCP_DEBUG, ("SYN "));
pehrhovey	0:a548a085de55	1372	}
pehrhovey	0:a548a085de55	1373	if (flags & TCP_RST) {
pehrhovey	0:a548a085de55	1374	LWIP_DEBUGF(TCP_DEBUG, ("RST "));
pehrhovey	0:a548a085de55	1375	}
pehrhovey	0:a548a085de55	1376	if (flags & TCP_PSH) {
pehrhovey	0:a548a085de55	1377	LWIP_DEBUGF(TCP_DEBUG, ("PSH "));
pehrhovey	0:a548a085de55	1378	}
pehrhovey	0:a548a085de55	1379	if (flags & TCP_ACK) {
pehrhovey	0:a548a085de55	1380	LWIP_DEBUGF(TCP_DEBUG, ("ACK "));
pehrhovey	0:a548a085de55	1381	}
pehrhovey	0:a548a085de55	1382	if (flags & TCP_URG) {
pehrhovey	0:a548a085de55	1383	LWIP_DEBUGF(TCP_DEBUG, ("URG "));
pehrhovey	0:a548a085de55	1384	}
pehrhovey	0:a548a085de55	1385	if (flags & TCP_ECE) {
pehrhovey	0:a548a085de55	1386	LWIP_DEBUGF(TCP_DEBUG, ("ECE "));
pehrhovey	0:a548a085de55	1387	}
pehrhovey	0:a548a085de55	1388	if (flags & TCP_CWR) {
pehrhovey	0:a548a085de55	1389	LWIP_DEBUGF(TCP_DEBUG, ("CWR "));
pehrhovey	0:a548a085de55	1390	}
pehrhovey	0:a548a085de55	1391	LWIP_DEBUGF(TCP_DEBUG, ("\n"));
pehrhovey	0:a548a085de55	1392	}
pehrhovey	0:a548a085de55	1393
pehrhovey	0:a548a085de55	1394	/**
pehrhovey	0:a548a085de55	1395	* Print all tcp_pcbs in every list for debugging purposes.
pehrhovey	0:a548a085de55	1396	*/
pehrhovey	0:a548a085de55	1397	void
pehrhovey	0:a548a085de55	1398	tcp_debug_print_pcbs(void)
pehrhovey	0:a548a085de55	1399	{
pehrhovey	0:a548a085de55	1400	struct tcp_pcb *pcb;
pehrhovey	0:a548a085de55	1401	LWIP_DEBUGF(TCP_DEBUG, ("Active PCB states:\n"));
pehrhovey	0:a548a085de55	1402	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	1403	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
pehrhovey	0:a548a085de55	1404	pcb->local_port, pcb->remote_port,
pehrhovey	0:a548a085de55	1405	pcb->snd_nxt, pcb->rcv_nxt));
pehrhovey	0:a548a085de55	1406	tcp_debug_print_state(pcb->state);
pehrhovey	0:a548a085de55	1407	}
pehrhovey	0:a548a085de55	1408	LWIP_DEBUGF(TCP_DEBUG, ("Listen PCB states:\n"));
pehrhovey	0:a548a085de55	1409	for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	1410	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
pehrhovey	0:a548a085de55	1411	pcb->local_port, pcb->remote_port,
pehrhovey	0:a548a085de55	1412	pcb->snd_nxt, pcb->rcv_nxt));
pehrhovey	0:a548a085de55	1413	tcp_debug_print_state(pcb->state);
pehrhovey	0:a548a085de55	1414	}
pehrhovey	0:a548a085de55	1415	LWIP_DEBUGF(TCP_DEBUG, ("TIME-WAIT PCB states:\n"));
pehrhovey	0:a548a085de55	1416	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	1417	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
pehrhovey	0:a548a085de55	1418	pcb->local_port, pcb->remote_port,
pehrhovey	0:a548a085de55	1419	pcb->snd_nxt, pcb->rcv_nxt));
pehrhovey	0:a548a085de55	1420	tcp_debug_print_state(pcb->state);
pehrhovey	0:a548a085de55	1421	}
pehrhovey	0:a548a085de55	1422	}
pehrhovey	0:a548a085de55	1423
pehrhovey	0:a548a085de55	1424	/**
pehrhovey	0:a548a085de55	1425	* Check state consistency of the tcp_pcb lists.
pehrhovey	0:a548a085de55	1426	*/
pehrhovey	0:a548a085de55	1427	s16_t
pehrhovey	0:a548a085de55	1428	tcp_pcbs_sane(void)
pehrhovey	0:a548a085de55	1429	{
pehrhovey	0:a548a085de55	1430	struct tcp_pcb *pcb;
pehrhovey	0:a548a085de55	1431	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	1432	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != CLOSED", pcb->state != CLOSED);
pehrhovey	0:a548a085de55	1433	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != LISTEN", pcb->state != LISTEN);
pehrhovey	0:a548a085de55	1434	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
pehrhovey	0:a548a085de55	1435	}
pehrhovey	0:a548a085de55	1436	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
pehrhovey	0:a548a085de55	1437	LWIP_ASSERT("tcp_pcbs_sane: tw pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
pehrhovey	0:a548a085de55	1438	}
pehrhovey	0:a548a085de55	1439	return 1;
pehrhovey	0:a548a085de55	1440	}
pehrhovey	0:a548a085de55	1441	#endif /* TCP_DEBUG */
pehrhovey	0:a548a085de55	1442
pehrhovey	0:a548a085de55	1443	#endif /* LWIP_TCP */

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	14 Mar 2010
Imports:	240
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	5

Core/lwIP/core/tcp.c@0:a548a085de55, 2010-03-14 (annotated)

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