IBMIoTClientEthernetExample - Port to C027 (using AppShield and Ethernet)

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u-blox / Mbed 2 deprecated IBMIoTClientEthernetExample

Port to C027 (using AppShield and Ethernet)

Dependencies: C12832 EthernetInterface LM75B MMA7660 MQTT mbed-rtos mbed

Fork of IBMIoTClientEthernetExample by IBM Watson IoT

EthernetInterface/lwip/core/tcp.c@6:37b6d0d56190, 2014-08-20 (annotated)

Committer:: samdanbury
Date:: Wed Aug 20 12:45:14 2014 +0000
Revision:: 6:37b6d0d56190

Code completely changed to improve the structure, flow and memory usage of the application

Who changed what in which revision?

User	Revision	Line number	New contents of line
samdanbury	6:37b6d0d56190	1	/**
samdanbury	6:37b6d0d56190	2	* @file
samdanbury	6:37b6d0d56190	3	* Transmission Control Protocol for IP
samdanbury	6:37b6d0d56190	4	*
samdanbury	6:37b6d0d56190	5	* This file contains common functions for the TCP implementation, such as functinos
samdanbury	6:37b6d0d56190	6	* for manipulating the data structures and the TCP timer functions. TCP functions
samdanbury	6:37b6d0d56190	7	* related to input and output is found in tcp_in.c and tcp_out.c respectively.
samdanbury	6:37b6d0d56190	8	*
samdanbury	6:37b6d0d56190	9	*/
samdanbury	6:37b6d0d56190	10
samdanbury	6:37b6d0d56190	11	/*
samdanbury	6:37b6d0d56190	12	* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
samdanbury	6:37b6d0d56190	13	* All rights reserved.
samdanbury	6:37b6d0d56190	14	*
samdanbury	6:37b6d0d56190	15	* Redistribution and use in source and binary forms, with or without modification,
samdanbury	6:37b6d0d56190	16	* are permitted provided that the following conditions are met:
samdanbury	6:37b6d0d56190	17	*
samdanbury	6:37b6d0d56190	18	* 1. Redistributions of source code must retain the above copyright notice,
samdanbury	6:37b6d0d56190	19	* this list of conditions and the following disclaimer.
samdanbury	6:37b6d0d56190	20	* 2. Redistributions in binary form must reproduce the above copyright notice,
samdanbury	6:37b6d0d56190	21	* this list of conditions and the following disclaimer in the documentation
samdanbury	6:37b6d0d56190	22	* and/or other materials provided with the distribution.
samdanbury	6:37b6d0d56190	23	* 3. The name of the author may not be used to endorse or promote products
samdanbury	6:37b6d0d56190	24	* derived from this software without specific prior written permission.
samdanbury	6:37b6d0d56190	25	*
samdanbury	6:37b6d0d56190	26	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
samdanbury	6:37b6d0d56190	27	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
samdanbury	6:37b6d0d56190	28	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
samdanbury	6:37b6d0d56190	29	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
samdanbury	6:37b6d0d56190	30	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
samdanbury	6:37b6d0d56190	31	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
samdanbury	6:37b6d0d56190	32	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
samdanbury	6:37b6d0d56190	33	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
samdanbury	6:37b6d0d56190	34	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
samdanbury	6:37b6d0d56190	35	* OF SUCH DAMAGE.
samdanbury	6:37b6d0d56190	36	*
samdanbury	6:37b6d0d56190	37	* This file is part of the lwIP TCP/IP stack.
samdanbury	6:37b6d0d56190	38	*
samdanbury	6:37b6d0d56190	39	* Author: Adam Dunkels <adam@sics.se>
samdanbury	6:37b6d0d56190	40	*
samdanbury	6:37b6d0d56190	41	*/
samdanbury	6:37b6d0d56190	42
samdanbury	6:37b6d0d56190	43	#include "lwip/opt.h"
samdanbury	6:37b6d0d56190	44
samdanbury	6:37b6d0d56190	45	#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
samdanbury	6:37b6d0d56190	46
samdanbury	6:37b6d0d56190	47	#include "lwip/def.h"
samdanbury	6:37b6d0d56190	48	#include "lwip/mem.h"
samdanbury	6:37b6d0d56190	49	#include "lwip/memp.h"
samdanbury	6:37b6d0d56190	50	#include "lwip/snmp.h"
samdanbury	6:37b6d0d56190	51	#include "lwip/tcp.h"
samdanbury	6:37b6d0d56190	52	#include "lwip/tcp_impl.h"
samdanbury	6:37b6d0d56190	53	#include "lwip/debug.h"
samdanbury	6:37b6d0d56190	54	#include "lwip/stats.h"
samdanbury	6:37b6d0d56190	55
samdanbury	6:37b6d0d56190	56	#include <string.h>
samdanbury	6:37b6d0d56190	57
samdanbury	6:37b6d0d56190	58	const char * const tcp_state_str[] = {
samdanbury	6:37b6d0d56190	59	"CLOSED",
samdanbury	6:37b6d0d56190	60	"LISTEN",
samdanbury	6:37b6d0d56190	61	"SYN_SENT",
samdanbury	6:37b6d0d56190	62	"SYN_RCVD",
samdanbury	6:37b6d0d56190	63	"ESTABLISHED",
samdanbury	6:37b6d0d56190	64	"FIN_WAIT_1",
samdanbury	6:37b6d0d56190	65	"FIN_WAIT_2",
samdanbury	6:37b6d0d56190	66	"CLOSE_WAIT",
samdanbury	6:37b6d0d56190	67	"CLOSING",
samdanbury	6:37b6d0d56190	68	"LAST_ACK",
samdanbury	6:37b6d0d56190	69	"TIME_WAIT"
samdanbury	6:37b6d0d56190	70	};
samdanbury	6:37b6d0d56190	71
samdanbury	6:37b6d0d56190	72	/* Incremented every coarse grained timer shot (typically every 500 ms). */
samdanbury	6:37b6d0d56190	73	u32_t tcp_ticks;
samdanbury	6:37b6d0d56190	74	const u8_t tcp_backoff[13] =
samdanbury	6:37b6d0d56190	75	{ 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7};
samdanbury	6:37b6d0d56190	76	/* Times per slowtmr hits */
samdanbury	6:37b6d0d56190	77	const u8_t tcp_persist_backoff[7] = { 3, 6, 12, 24, 48, 96, 120 };
samdanbury	6:37b6d0d56190	78
samdanbury	6:37b6d0d56190	79	/* The TCP PCB lists. */
samdanbury	6:37b6d0d56190	80
samdanbury	6:37b6d0d56190	81	/** List of all TCP PCBs bound but not yet (connected \|\| listening) */
samdanbury	6:37b6d0d56190	82	struct tcp_pcb *tcp_bound_pcbs;
samdanbury	6:37b6d0d56190	83	/** List of all TCP PCBs in LISTEN state */
samdanbury	6:37b6d0d56190	84	union tcp_listen_pcbs_t tcp_listen_pcbs;
samdanbury	6:37b6d0d56190	85	/** List of all TCP PCBs that are in a state in which
samdanbury	6:37b6d0d56190	86	* they accept or send data. */
samdanbury	6:37b6d0d56190	87	struct tcp_pcb *tcp_active_pcbs;
samdanbury	6:37b6d0d56190	88	/** List of all TCP PCBs in TIME-WAIT state */
samdanbury	6:37b6d0d56190	89	struct tcp_pcb *tcp_tw_pcbs;
samdanbury	6:37b6d0d56190	90
samdanbury	6:37b6d0d56190	91	#define NUM_TCP_PCB_LISTS 4
samdanbury	6:37b6d0d56190	92	#define NUM_TCP_PCB_LISTS_NO_TIME_WAIT 3
samdanbury	6:37b6d0d56190	93	/** An array with all (non-temporary) PCB lists, mainly used for smaller code size */
samdanbury	6:37b6d0d56190	94	struct tcp_pcb ** const tcp_pcb_lists[] = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
samdanbury	6:37b6d0d56190	95	&tcp_active_pcbs, &tcp_tw_pcbs};
samdanbury	6:37b6d0d56190	96
samdanbury	6:37b6d0d56190	97	/** Only used for temporary storage. */
samdanbury	6:37b6d0d56190	98	struct tcp_pcb *tcp_tmp_pcb;
samdanbury	6:37b6d0d56190	99
samdanbury	6:37b6d0d56190	100	/** Timer counter to handle calling slow-timer from tcp_tmr() */
samdanbury	6:37b6d0d56190	101	static u8_t tcp_timer;
samdanbury	6:37b6d0d56190	102	static u16_t tcp_new_port(void);
samdanbury	6:37b6d0d56190	103
samdanbury	6:37b6d0d56190	104	/**
samdanbury	6:37b6d0d56190	105	* Called periodically to dispatch TCP timers.
samdanbury	6:37b6d0d56190	106	*
samdanbury	6:37b6d0d56190	107	*/
samdanbury	6:37b6d0d56190	108	void
samdanbury	6:37b6d0d56190	109	tcp_tmr(void)
samdanbury	6:37b6d0d56190	110	{
samdanbury	6:37b6d0d56190	111	/* Call tcp_fasttmr() every 250 ms */
samdanbury	6:37b6d0d56190	112	tcp_fasttmr();
samdanbury	6:37b6d0d56190	113
samdanbury	6:37b6d0d56190	114	if (++tcp_timer & 1) {
samdanbury	6:37b6d0d56190	115	/* Call tcp_tmr() every 500 ms, i.e., every other timer
samdanbury	6:37b6d0d56190	116	tcp_tmr() is called. */
samdanbury	6:37b6d0d56190	117	tcp_slowtmr();
samdanbury	6:37b6d0d56190	118	}
samdanbury	6:37b6d0d56190	119	}
samdanbury	6:37b6d0d56190	120
samdanbury	6:37b6d0d56190	121	/**
samdanbury	6:37b6d0d56190	122	* Closes the TX side of a connection held by the PCB.
samdanbury	6:37b6d0d56190	123	* For tcp_close(), a RST is sent if the application didn't receive all data
samdanbury	6:37b6d0d56190	124	* (tcp_recved() not called for all data passed to recv callback).
samdanbury	6:37b6d0d56190	125	*
samdanbury	6:37b6d0d56190	126	* Listening pcbs are freed and may not be referenced any more.
samdanbury	6:37b6d0d56190	127	* Connection pcbs are freed if not yet connected and may not be referenced
samdanbury	6:37b6d0d56190	128	* any more. If a connection is established (at least SYN received or in
samdanbury	6:37b6d0d56190	129	* a closing state), the connection is closed, and put in a closing state.
samdanbury	6:37b6d0d56190	130	* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
samdanbury	6:37b6d0d56190	131	* unsafe to reference it.
samdanbury	6:37b6d0d56190	132	*
samdanbury	6:37b6d0d56190	133	* @param pcb the tcp_pcb to close
samdanbury	6:37b6d0d56190	134	* @return ERR_OK if connection has been closed
samdanbury	6:37b6d0d56190	135	* another err_t if closing failed and pcb is not freed
samdanbury	6:37b6d0d56190	136	*/
samdanbury	6:37b6d0d56190	137	static err_t
samdanbury	6:37b6d0d56190	138	tcp_close_shutdown(struct tcp_pcb *pcb, u8_t rst_on_unacked_data)
samdanbury	6:37b6d0d56190	139	{
samdanbury	6:37b6d0d56190	140	err_t err;
samdanbury	6:37b6d0d56190	141
samdanbury	6:37b6d0d56190	142	if (rst_on_unacked_data && (pcb->state != LISTEN)) {
samdanbury	6:37b6d0d56190	143	if ((pcb->refused_data != NULL) \|\| (pcb->rcv_wnd != TCP_WND)) {
samdanbury	6:37b6d0d56190	144	/* Not all data received by application, send RST to tell the remote
samdanbury	6:37b6d0d56190	145	side about this. */
samdanbury	6:37b6d0d56190	146	LWIP_ASSERT("pcb->flags & TF_RXCLOSED", pcb->flags & TF_RXCLOSED);
samdanbury	6:37b6d0d56190	147
samdanbury	6:37b6d0d56190	148	/* don't call tcp_abort here: we must not deallocate the pcb since
samdanbury	6:37b6d0d56190	149	that might not be expected when calling tcp_close */
samdanbury	6:37b6d0d56190	150	tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
samdanbury	6:37b6d0d56190	151	pcb->local_port, pcb->remote_port);
samdanbury	6:37b6d0d56190	152
samdanbury	6:37b6d0d56190	153	tcp_pcb_purge(pcb);
samdanbury	6:37b6d0d56190	154
samdanbury	6:37b6d0d56190	155	/* TODO: to which state do we move now? */
samdanbury	6:37b6d0d56190	156
samdanbury	6:37b6d0d56190	157	/* move to TIME_WAIT since we close actively */
samdanbury	6:37b6d0d56190	158	TCP_RMV(&tcp_active_pcbs, pcb);
samdanbury	6:37b6d0d56190	159	pcb->state = TIME_WAIT;
samdanbury	6:37b6d0d56190	160	TCP_REG(&tcp_tw_pcbs, pcb);
samdanbury	6:37b6d0d56190	161
samdanbury	6:37b6d0d56190	162	return ERR_OK;
samdanbury	6:37b6d0d56190	163	}
samdanbury	6:37b6d0d56190	164	}
samdanbury	6:37b6d0d56190	165
samdanbury	6:37b6d0d56190	166	switch (pcb->state) {
samdanbury	6:37b6d0d56190	167	case CLOSED:
samdanbury	6:37b6d0d56190	168	/* Closing a pcb in the CLOSED state might seem erroneous,
samdanbury	6:37b6d0d56190	169	* however, it is in this state once allocated and as yet unused
samdanbury	6:37b6d0d56190	170	* and the user needs some way to free it should the need arise.
samdanbury	6:37b6d0d56190	171	* Calling tcp_close() with a pcb that has already been closed, (i.e. twice)
samdanbury	6:37b6d0d56190	172	* or for a pcb that has been used and then entered the CLOSED state
samdanbury	6:37b6d0d56190	173	* is erroneous, but this should never happen as the pcb has in those cases
samdanbury	6:37b6d0d56190	174	* been freed, and so any remaining handles are bogus. */
samdanbury	6:37b6d0d56190	175	err = ERR_OK;
samdanbury	6:37b6d0d56190	176	if (pcb->local_port != 0) {
samdanbury	6:37b6d0d56190	177	TCP_RMV(&tcp_bound_pcbs, pcb);
samdanbury	6:37b6d0d56190	178	}
samdanbury	6:37b6d0d56190	179	memp_free(MEMP_TCP_PCB, pcb);
samdanbury	6:37b6d0d56190	180	pcb = NULL;
samdanbury	6:37b6d0d56190	181	break;
samdanbury	6:37b6d0d56190	182	case LISTEN:
samdanbury	6:37b6d0d56190	183	err = ERR_OK;
samdanbury	6:37b6d0d56190	184	tcp_pcb_remove(&tcp_listen_pcbs.pcbs, pcb);
samdanbury	6:37b6d0d56190	185	memp_free(MEMP_TCP_PCB_LISTEN, pcb);
samdanbury	6:37b6d0d56190	186	pcb = NULL;
samdanbury	6:37b6d0d56190	187	break;
samdanbury	6:37b6d0d56190	188	case SYN_SENT:
samdanbury	6:37b6d0d56190	189	err = ERR_OK;
samdanbury	6:37b6d0d56190	190	tcp_pcb_remove(&tcp_active_pcbs, pcb);
samdanbury	6:37b6d0d56190	191	memp_free(MEMP_TCP_PCB, pcb);
samdanbury	6:37b6d0d56190	192	pcb = NULL;
samdanbury	6:37b6d0d56190	193	snmp_inc_tcpattemptfails();
samdanbury	6:37b6d0d56190	194	break;
samdanbury	6:37b6d0d56190	195	case SYN_RCVD:
samdanbury	6:37b6d0d56190	196	err = tcp_send_fin(pcb);
samdanbury	6:37b6d0d56190	197	if (err == ERR_OK) {
samdanbury	6:37b6d0d56190	198	snmp_inc_tcpattemptfails();
samdanbury	6:37b6d0d56190	199	pcb->state = FIN_WAIT_1;
samdanbury	6:37b6d0d56190	200	}
samdanbury	6:37b6d0d56190	201	break;
samdanbury	6:37b6d0d56190	202	case ESTABLISHED:
samdanbury	6:37b6d0d56190	203	err = tcp_send_fin(pcb);
samdanbury	6:37b6d0d56190	204	if (err == ERR_OK) {
samdanbury	6:37b6d0d56190	205	snmp_inc_tcpestabresets();
samdanbury	6:37b6d0d56190	206	pcb->state = FIN_WAIT_1;
samdanbury	6:37b6d0d56190	207	}
samdanbury	6:37b6d0d56190	208	break;
samdanbury	6:37b6d0d56190	209	case CLOSE_WAIT:
samdanbury	6:37b6d0d56190	210	err = tcp_send_fin(pcb);
samdanbury	6:37b6d0d56190	211	if (err == ERR_OK) {
samdanbury	6:37b6d0d56190	212	snmp_inc_tcpestabresets();
samdanbury	6:37b6d0d56190	213	pcb->state = LAST_ACK;
samdanbury	6:37b6d0d56190	214	}
samdanbury	6:37b6d0d56190	215	break;
samdanbury	6:37b6d0d56190	216	default:
samdanbury	6:37b6d0d56190	217	/* Has already been closed, do nothing. */
samdanbury	6:37b6d0d56190	218	err = ERR_OK;
samdanbury	6:37b6d0d56190	219	pcb = NULL;
samdanbury	6:37b6d0d56190	220	break;
samdanbury	6:37b6d0d56190	221	}
samdanbury	6:37b6d0d56190	222
samdanbury	6:37b6d0d56190	223	if (pcb != NULL && err == ERR_OK) {
samdanbury	6:37b6d0d56190	224	/* To ensure all data has been sent when tcp_close returns, we have
samdanbury	6:37b6d0d56190	225	to make sure tcp_output doesn't fail.
samdanbury	6:37b6d0d56190	226	Since we don't really have to ensure all data has been sent when tcp_close
samdanbury	6:37b6d0d56190	227	returns (unsent data is sent from tcp timer functions, also), we don't care
samdanbury	6:37b6d0d56190	228	for the return value of tcp_output for now. */
samdanbury	6:37b6d0d56190	229	/* @todo: When implementing SO_LINGER, this must be changed somehow:
samdanbury	6:37b6d0d56190	230	If SOF_LINGER is set, the data should be sent and acked before close returns.
samdanbury	6:37b6d0d56190	231	This can only be valid for sequential APIs, not for the raw API. */
samdanbury	6:37b6d0d56190	232	tcp_output(pcb);
samdanbury	6:37b6d0d56190	233	}
samdanbury	6:37b6d0d56190	234	return err;
samdanbury	6:37b6d0d56190	235	}
samdanbury	6:37b6d0d56190	236
samdanbury	6:37b6d0d56190	237	/**
samdanbury	6:37b6d0d56190	238	* Closes the connection held by the PCB.
samdanbury	6:37b6d0d56190	239	*
samdanbury	6:37b6d0d56190	240	* Listening pcbs are freed and may not be referenced any more.
samdanbury	6:37b6d0d56190	241	* Connection pcbs are freed if not yet connected and may not be referenced
samdanbury	6:37b6d0d56190	242	* any more. If a connection is established (at least SYN received or in
samdanbury	6:37b6d0d56190	243	* a closing state), the connection is closed, and put in a closing state.
samdanbury	6:37b6d0d56190	244	* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
samdanbury	6:37b6d0d56190	245	* unsafe to reference it (unless an error is returned).
samdanbury	6:37b6d0d56190	246	*
samdanbury	6:37b6d0d56190	247	* @param pcb the tcp_pcb to close
samdanbury	6:37b6d0d56190	248	* @return ERR_OK if connection has been closed
samdanbury	6:37b6d0d56190	249	* another err_t if closing failed and pcb is not freed
samdanbury	6:37b6d0d56190	250	*/
samdanbury	6:37b6d0d56190	251	err_t
samdanbury	6:37b6d0d56190	252	tcp_close(struct tcp_pcb *pcb)
samdanbury	6:37b6d0d56190	253	{
samdanbury	6:37b6d0d56190	254	#if TCP_DEBUG
samdanbury	6:37b6d0d56190	255	LWIP_DEBUGF(TCP_DEBUG, ("tcp_close: closing in "));
samdanbury	6:37b6d0d56190	256	tcp_debug_print_state(pcb->state);
samdanbury	6:37b6d0d56190	257	#endif /* TCP_DEBUG */
samdanbury	6:37b6d0d56190	258
samdanbury	6:37b6d0d56190	259	if (pcb->state != LISTEN) {
samdanbury	6:37b6d0d56190	260	/* Set a flag not to receive any more data... */
samdanbury	6:37b6d0d56190	261	pcb->flags \|= TF_RXCLOSED;
samdanbury	6:37b6d0d56190	262	}
samdanbury	6:37b6d0d56190	263	/* ... and close */
samdanbury	6:37b6d0d56190	264	return tcp_close_shutdown(pcb, 1);
samdanbury	6:37b6d0d56190	265	}
samdanbury	6:37b6d0d56190	266
samdanbury	6:37b6d0d56190	267	/**
samdanbury	6:37b6d0d56190	268	* Causes all or part of a full-duplex connection of this PCB to be shut down.
samdanbury	6:37b6d0d56190	269	* This doesn't deallocate the PCB!
samdanbury	6:37b6d0d56190	270	*
samdanbury	6:37b6d0d56190	271	* @param pcb PCB to shutdown
samdanbury	6:37b6d0d56190	272	* @param shut_rx shut down receive side if this is != 0
samdanbury	6:37b6d0d56190	273	* @param shut_tx shut down send side if this is != 0
samdanbury	6:37b6d0d56190	274	* @return ERR_OK if shutdown succeeded (or the PCB has already been shut down)
samdanbury	6:37b6d0d56190	275	* another err_t on error.
samdanbury	6:37b6d0d56190	276	*/
samdanbury	6:37b6d0d56190	277	err_t
samdanbury	6:37b6d0d56190	278	tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx)
samdanbury	6:37b6d0d56190	279	{
samdanbury	6:37b6d0d56190	280	if (pcb->state == LISTEN) {
samdanbury	6:37b6d0d56190	281	return ERR_CONN;
samdanbury	6:37b6d0d56190	282	}
samdanbury	6:37b6d0d56190	283	if (shut_rx) {
samdanbury	6:37b6d0d56190	284	/* shut down the receive side: free buffered data... */
samdanbury	6:37b6d0d56190	285	if (pcb->refused_data != NULL) {
samdanbury	6:37b6d0d56190	286	pbuf_free(pcb->refused_data);
samdanbury	6:37b6d0d56190	287	pcb->refused_data = NULL;
samdanbury	6:37b6d0d56190	288	}
samdanbury	6:37b6d0d56190	289	/* ... and set a flag not to receive any more data */
samdanbury	6:37b6d0d56190	290	pcb->flags \|= TF_RXCLOSED;
samdanbury	6:37b6d0d56190	291	}
samdanbury	6:37b6d0d56190	292	if (shut_tx) {
samdanbury	6:37b6d0d56190	293	/* This can't happen twice since if it succeeds, the pcb's state is changed.
samdanbury	6:37b6d0d56190	294	Only close in these states as the others directly deallocate the PCB */
samdanbury	6:37b6d0d56190	295	switch (pcb->state) {
samdanbury	6:37b6d0d56190	296	case SYN_RCVD:
samdanbury	6:37b6d0d56190	297	case ESTABLISHED:
samdanbury	6:37b6d0d56190	298	case CLOSE_WAIT:
samdanbury	6:37b6d0d56190	299	return tcp_close_shutdown(pcb, 0);
samdanbury	6:37b6d0d56190	300	default:
samdanbury	6:37b6d0d56190	301	/* don't shut down other states */
samdanbury	6:37b6d0d56190	302	break;
samdanbury	6:37b6d0d56190	303	}
samdanbury	6:37b6d0d56190	304	}
samdanbury	6:37b6d0d56190	305	/* @todo: return another err_t if not in correct state or already shut? */
samdanbury	6:37b6d0d56190	306	return ERR_OK;
samdanbury	6:37b6d0d56190	307	}
samdanbury	6:37b6d0d56190	308
samdanbury	6:37b6d0d56190	309	/**
samdanbury	6:37b6d0d56190	310	* Abandons a connection and optionally sends a RST to the remote
samdanbury	6:37b6d0d56190	311	* host. Deletes the local protocol control block. This is done when
samdanbury	6:37b6d0d56190	312	* a connection is killed because of shortage of memory.
samdanbury	6:37b6d0d56190	313	*
samdanbury	6:37b6d0d56190	314	* @param pcb the tcp_pcb to abort
samdanbury	6:37b6d0d56190	315	* @param reset boolean to indicate whether a reset should be sent
samdanbury	6:37b6d0d56190	316	*/
samdanbury	6:37b6d0d56190	317	void
samdanbury	6:37b6d0d56190	318	tcp_abandon(struct tcp_pcb *pcb, int reset)
samdanbury	6:37b6d0d56190	319	{
samdanbury	6:37b6d0d56190	320	u32_t seqno, ackno;
samdanbury	6:37b6d0d56190	321	u16_t remote_port, local_port;
samdanbury	6:37b6d0d56190	322	ip_addr_t remote_ip, local_ip;
samdanbury	6:37b6d0d56190	323	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	324	tcp_err_fn errf;
samdanbury	6:37b6d0d56190	325	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	326	void *errf_arg;
samdanbury	6:37b6d0d56190	327
samdanbury	6:37b6d0d56190	328	/* pcb->state LISTEN not allowed here */
samdanbury	6:37b6d0d56190	329	LWIP_ASSERT("don't call tcp_abort/tcp_abandon for listen-pcbs",
samdanbury	6:37b6d0d56190	330	pcb->state != LISTEN);
samdanbury	6:37b6d0d56190	331	/* Figure out on which TCP PCB list we are, and remove us. If we
samdanbury	6:37b6d0d56190	332	are in an active state, call the receive function associated with
samdanbury	6:37b6d0d56190	333	the PCB with a NULL argument, and send an RST to the remote end. */
samdanbury	6:37b6d0d56190	334	if (pcb->state == TIME_WAIT) {
samdanbury	6:37b6d0d56190	335	tcp_pcb_remove(&tcp_tw_pcbs, pcb);
samdanbury	6:37b6d0d56190	336	memp_free(MEMP_TCP_PCB, pcb);
samdanbury	6:37b6d0d56190	337	} else {
samdanbury	6:37b6d0d56190	338	seqno = pcb->snd_nxt;
samdanbury	6:37b6d0d56190	339	ackno = pcb->rcv_nxt;
samdanbury	6:37b6d0d56190	340	ip_addr_copy(local_ip, pcb->local_ip);
samdanbury	6:37b6d0d56190	341	ip_addr_copy(remote_ip, pcb->remote_ip);
samdanbury	6:37b6d0d56190	342	local_port = pcb->local_port;
samdanbury	6:37b6d0d56190	343	remote_port = pcb->remote_port;
samdanbury	6:37b6d0d56190	344	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	345	errf = pcb->errf;
samdanbury	6:37b6d0d56190	346	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	347	errf_arg = pcb->callback_arg;
samdanbury	6:37b6d0d56190	348	tcp_pcb_remove(&tcp_active_pcbs, pcb);
samdanbury	6:37b6d0d56190	349	if (pcb->unacked != NULL) {
samdanbury	6:37b6d0d56190	350	tcp_segs_free(pcb->unacked);
samdanbury	6:37b6d0d56190	351	}
samdanbury	6:37b6d0d56190	352	if (pcb->unsent != NULL) {
samdanbury	6:37b6d0d56190	353	tcp_segs_free(pcb->unsent);
samdanbury	6:37b6d0d56190	354	}
samdanbury	6:37b6d0d56190	355	#if TCP_QUEUE_OOSEQ
samdanbury	6:37b6d0d56190	356	if (pcb->ooseq != NULL) {
samdanbury	6:37b6d0d56190	357	tcp_segs_free(pcb->ooseq);
samdanbury	6:37b6d0d56190	358	}
samdanbury	6:37b6d0d56190	359	#endif /* TCP_QUEUE_OOSEQ */
samdanbury	6:37b6d0d56190	360	memp_free(MEMP_TCP_PCB, pcb);
samdanbury	6:37b6d0d56190	361	TCP_EVENT_ERR(errf, errf_arg, ERR_ABRT);
samdanbury	6:37b6d0d56190	362	if (reset) {
samdanbury	6:37b6d0d56190	363	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_abandon: sending RST\n"));
samdanbury	6:37b6d0d56190	364	tcp_rst(seqno, ackno, &local_ip, &remote_ip, local_port, remote_port);
samdanbury	6:37b6d0d56190	365	}
samdanbury	6:37b6d0d56190	366	}
samdanbury	6:37b6d0d56190	367	}
samdanbury	6:37b6d0d56190	368
samdanbury	6:37b6d0d56190	369	/**
samdanbury	6:37b6d0d56190	370	* Aborts the connection by sending a RST (reset) segment to the remote
samdanbury	6:37b6d0d56190	371	* host. The pcb is deallocated. This function never fails.
samdanbury	6:37b6d0d56190	372	*
samdanbury	6:37b6d0d56190	373	* ATTENTION: When calling this from one of the TCP callbacks, make
samdanbury	6:37b6d0d56190	374	* sure you always return ERR_ABRT (and never return ERR_ABRT otherwise
samdanbury	6:37b6d0d56190	375	* or you will risk accessing deallocated memory or memory leaks!
samdanbury	6:37b6d0d56190	376	*
samdanbury	6:37b6d0d56190	377	* @param pcb the tcp pcb to abort
samdanbury	6:37b6d0d56190	378	*/
samdanbury	6:37b6d0d56190	379	void
samdanbury	6:37b6d0d56190	380	tcp_abort(struct tcp_pcb *pcb)
samdanbury	6:37b6d0d56190	381	{
samdanbury	6:37b6d0d56190	382	tcp_abandon(pcb, 1);
samdanbury	6:37b6d0d56190	383	}
samdanbury	6:37b6d0d56190	384
samdanbury	6:37b6d0d56190	385	/**
samdanbury	6:37b6d0d56190	386	* Binds the connection to a local portnumber and IP address. If the
samdanbury	6:37b6d0d56190	387	* IP address is not given (i.e., ipaddr == NULL), the IP address of
samdanbury	6:37b6d0d56190	388	* the outgoing network interface is used instead.
samdanbury	6:37b6d0d56190	389	*
samdanbury	6:37b6d0d56190	390	* @param pcb the tcp_pcb to bind (no check is done whether this pcb is
samdanbury	6:37b6d0d56190	391	* already bound!)
samdanbury	6:37b6d0d56190	392	* @param ipaddr the local ip address to bind to (use IP_ADDR_ANY to bind
samdanbury	6:37b6d0d56190	393	* to any local address
samdanbury	6:37b6d0d56190	394	* @param port the local port to bind to
samdanbury	6:37b6d0d56190	395	* @return ERR_USE if the port is already in use
samdanbury	6:37b6d0d56190	396	* ERR_VAL if bind failed because the PCB is not in a valid state
samdanbury	6:37b6d0d56190	397	* ERR_OK if bound
samdanbury	6:37b6d0d56190	398	*/
samdanbury	6:37b6d0d56190	399	err_t
samdanbury	6:37b6d0d56190	400	tcp_bind(struct tcp_pcb pcb, ip_addr_t ipaddr, u16_t port)
samdanbury	6:37b6d0d56190	401	{
samdanbury	6:37b6d0d56190	402	int i;
samdanbury	6:37b6d0d56190	403	int max_pcb_list = NUM_TCP_PCB_LISTS;
samdanbury	6:37b6d0d56190	404	struct tcp_pcb *cpcb;
samdanbury	6:37b6d0d56190	405
samdanbury	6:37b6d0d56190	406	LWIP_ERROR("tcp_bind: can only bind in state CLOSED", pcb->state == CLOSED, return ERR_VAL);
samdanbury	6:37b6d0d56190	407
samdanbury	6:37b6d0d56190	408	#if SO_REUSE
samdanbury	6:37b6d0d56190	409	/* Unless the REUSEADDR flag is set,
samdanbury	6:37b6d0d56190	410	we have to check the pcbs in TIME-WAIT state, also.
samdanbury	6:37b6d0d56190	411	We do not dump TIME_WAIT pcb's; they can still be matched by incoming
samdanbury	6:37b6d0d56190	412	packets using both local and remote IP addresses and ports to distinguish.
samdanbury	6:37b6d0d56190	413	*/
samdanbury	6:37b6d0d56190	414	if ((pcb->so_options & SOF_REUSEADDR) != 0) {
samdanbury	6:37b6d0d56190	415	max_pcb_list = NUM_TCP_PCB_LISTS_NO_TIME_WAIT;
samdanbury	6:37b6d0d56190	416	}
samdanbury	6:37b6d0d56190	417	#endif /* SO_REUSE */
samdanbury	6:37b6d0d56190	418
samdanbury	6:37b6d0d56190	419	if (port == 0) {
samdanbury	6:37b6d0d56190	420	port = tcp_new_port();
samdanbury	6:37b6d0d56190	421	}
samdanbury	6:37b6d0d56190	422
samdanbury	6:37b6d0d56190	423	/* Check if the address already is in use (on all lists) */
samdanbury	6:37b6d0d56190	424	for (i = 0; i < max_pcb_list; i++) {
samdanbury	6:37b6d0d56190	425	for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
samdanbury	6:37b6d0d56190	426	if (cpcb->local_port == port) {
samdanbury	6:37b6d0d56190	427	#if SO_REUSE
samdanbury	6:37b6d0d56190	428	/* Omit checking for the same port if both pcbs have REUSEADDR set.
samdanbury	6:37b6d0d56190	429	For SO_REUSEADDR, the duplicate-check for a 5-tuple is done in
samdanbury	6:37b6d0d56190	430	tcp_connect. */
samdanbury	6:37b6d0d56190	431	if (((pcb->so_options & SOF_REUSEADDR) == 0) \|\|
samdanbury	6:37b6d0d56190	432	((cpcb->so_options & SOF_REUSEADDR) == 0))
samdanbury	6:37b6d0d56190	433	#endif /* SO_REUSE */
samdanbury	6:37b6d0d56190	434	{
samdanbury	6:37b6d0d56190	435	if (ip_addr_isany(&(cpcb->local_ip)) \|\|
samdanbury	6:37b6d0d56190	436	ip_addr_isany(ipaddr) \|\|
samdanbury	6:37b6d0d56190	437	ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
samdanbury	6:37b6d0d56190	438	return ERR_USE;
samdanbury	6:37b6d0d56190	439	}
samdanbury	6:37b6d0d56190	440	}
samdanbury	6:37b6d0d56190	441	}
samdanbury	6:37b6d0d56190	442	}
samdanbury	6:37b6d0d56190	443	}
samdanbury	6:37b6d0d56190	444
samdanbury	6:37b6d0d56190	445	if (!ip_addr_isany(ipaddr)) {
samdanbury	6:37b6d0d56190	446	pcb->local_ip = *ipaddr;
samdanbury	6:37b6d0d56190	447	}
samdanbury	6:37b6d0d56190	448	pcb->local_port = port;
samdanbury	6:37b6d0d56190	449	TCP_REG(&tcp_bound_pcbs, pcb);
samdanbury	6:37b6d0d56190	450	LWIP_DEBUGF(TCP_DEBUG, ("tcp_bind: bind to port %"U16_F"\n", port));
samdanbury	6:37b6d0d56190	451	return ERR_OK;
samdanbury	6:37b6d0d56190	452	}
samdanbury	6:37b6d0d56190	453	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	454	/**
samdanbury	6:37b6d0d56190	455	* Default accept callback if no accept callback is specified by the user.
samdanbury	6:37b6d0d56190	456	*/
samdanbury	6:37b6d0d56190	457	static err_t
samdanbury	6:37b6d0d56190	458	tcp_accept_null(void arg, struct tcp_pcb pcb, err_t err)
samdanbury	6:37b6d0d56190	459	{
samdanbury	6:37b6d0d56190	460	LWIP_UNUSED_ARG(arg);
samdanbury	6:37b6d0d56190	461	LWIP_UNUSED_ARG(pcb);
samdanbury	6:37b6d0d56190	462	LWIP_UNUSED_ARG(err);
samdanbury	6:37b6d0d56190	463
samdanbury	6:37b6d0d56190	464	return ERR_ABRT;
samdanbury	6:37b6d0d56190	465	}
samdanbury	6:37b6d0d56190	466	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	467
samdanbury	6:37b6d0d56190	468	/**
samdanbury	6:37b6d0d56190	469	* Set the state of the connection to be LISTEN, which means that it
samdanbury	6:37b6d0d56190	470	* is able to accept incoming connections. The protocol control block
samdanbury	6:37b6d0d56190	471	* is reallocated in order to consume less memory. Setting the
samdanbury	6:37b6d0d56190	472	* connection to LISTEN is an irreversible process.
samdanbury	6:37b6d0d56190	473	*
samdanbury	6:37b6d0d56190	474	* @param pcb the original tcp_pcb
samdanbury	6:37b6d0d56190	475	* @param backlog the incoming connections queue limit
samdanbury	6:37b6d0d56190	476	* @return tcp_pcb used for listening, consumes less memory.
samdanbury	6:37b6d0d56190	477	*
samdanbury	6:37b6d0d56190	478	* @note The original tcp_pcb is freed. This function therefore has to be
samdanbury	6:37b6d0d56190	479	* called like this:
samdanbury	6:37b6d0d56190	480	* tpcb = tcp_listen(tpcb);
samdanbury	6:37b6d0d56190	481	*/
samdanbury	6:37b6d0d56190	482	struct tcp_pcb *
samdanbury	6:37b6d0d56190	483	tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
samdanbury	6:37b6d0d56190	484	{
samdanbury	6:37b6d0d56190	485	struct tcp_pcb_listen *lpcb;
samdanbury	6:37b6d0d56190	486
samdanbury	6:37b6d0d56190	487	LWIP_UNUSED_ARG(backlog);
samdanbury	6:37b6d0d56190	488	LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
samdanbury	6:37b6d0d56190	489
samdanbury	6:37b6d0d56190	490	/* already listening? */
samdanbury	6:37b6d0d56190	491	if (pcb->state == LISTEN) {
samdanbury	6:37b6d0d56190	492	return pcb;
samdanbury	6:37b6d0d56190	493	}
samdanbury	6:37b6d0d56190	494	#if SO_REUSE
samdanbury	6:37b6d0d56190	495	if ((pcb->so_options & SOF_REUSEADDR) != 0) {
samdanbury	6:37b6d0d56190	496	/* Since SOF_REUSEADDR allows reusing a local address before the pcb's usage
samdanbury	6:37b6d0d56190	497	is declared (listen-/connection-pcb), we have to make sure now that
samdanbury	6:37b6d0d56190	498	this port is only used once for every local IP. */
samdanbury	6:37b6d0d56190	499	for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
samdanbury	6:37b6d0d56190	500	if (lpcb->local_port == pcb->local_port) {
samdanbury	6:37b6d0d56190	501	if (ip_addr_cmp(&lpcb->local_ip, &pcb->local_ip)) {
samdanbury	6:37b6d0d56190	502	/* this address/port is already used */
samdanbury	6:37b6d0d56190	503	return NULL;
samdanbury	6:37b6d0d56190	504	}
samdanbury	6:37b6d0d56190	505	}
samdanbury	6:37b6d0d56190	506	}
samdanbury	6:37b6d0d56190	507	}
samdanbury	6:37b6d0d56190	508	#endif /* SO_REUSE */
samdanbury	6:37b6d0d56190	509	lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);
samdanbury	6:37b6d0d56190	510	if (lpcb == NULL) {
samdanbury	6:37b6d0d56190	511	return NULL;
samdanbury	6:37b6d0d56190	512	}
samdanbury	6:37b6d0d56190	513	lpcb->callback_arg = pcb->callback_arg;
samdanbury	6:37b6d0d56190	514	lpcb->local_port = pcb->local_port;
samdanbury	6:37b6d0d56190	515	lpcb->state = LISTEN;
samdanbury	6:37b6d0d56190	516	lpcb->prio = pcb->prio;
samdanbury	6:37b6d0d56190	517	lpcb->so_options = pcb->so_options;
samdanbury	6:37b6d0d56190	518	lpcb->so_options \|= SOF_ACCEPTCONN;
samdanbury	6:37b6d0d56190	519	lpcb->ttl = pcb->ttl;
samdanbury	6:37b6d0d56190	520	lpcb->tos = pcb->tos;
samdanbury	6:37b6d0d56190	521	ip_addr_copy(lpcb->local_ip, pcb->local_ip);
samdanbury	6:37b6d0d56190	522	if (pcb->local_port != 0) {
samdanbury	6:37b6d0d56190	523	TCP_RMV(&tcp_bound_pcbs, pcb);
samdanbury	6:37b6d0d56190	524	}
samdanbury	6:37b6d0d56190	525	memp_free(MEMP_TCP_PCB, pcb);
samdanbury	6:37b6d0d56190	526	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	527	lpcb->accept = tcp_accept_null;
samdanbury	6:37b6d0d56190	528	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	529	#if TCP_LISTEN_BACKLOG
samdanbury	6:37b6d0d56190	530	lpcb->accepts_pending = 0;
samdanbury	6:37b6d0d56190	531	lpcb->backlog = (backlog ? backlog : 1);
samdanbury	6:37b6d0d56190	532	#endif /* TCP_LISTEN_BACKLOG */
samdanbury	6:37b6d0d56190	533	TCP_REG(&tcp_listen_pcbs.pcbs, (struct tcp_pcb *)lpcb);
samdanbury	6:37b6d0d56190	534	return (struct tcp_pcb *)lpcb;
samdanbury	6:37b6d0d56190	535	}
samdanbury	6:37b6d0d56190	536
samdanbury	6:37b6d0d56190	537	/**
samdanbury	6:37b6d0d56190	538	* Update the state that tracks the available window space to advertise.
samdanbury	6:37b6d0d56190	539	*
samdanbury	6:37b6d0d56190	540	* Returns how much extra window would be advertised if we sent an
samdanbury	6:37b6d0d56190	541	* update now.
samdanbury	6:37b6d0d56190	542	*/
samdanbury	6:37b6d0d56190	543	u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb)
samdanbury	6:37b6d0d56190	544	{
samdanbury	6:37b6d0d56190	545	u32_t new_right_edge = pcb->rcv_nxt + pcb->rcv_wnd;
samdanbury	6:37b6d0d56190	546
samdanbury	6:37b6d0d56190	547	if (TCP_SEQ_GEQ(new_right_edge, pcb->rcv_ann_right_edge + LWIP_MIN((TCP_WND / 2), pcb->mss))) {
samdanbury	6:37b6d0d56190	548	/* we can advertise more window */
samdanbury	6:37b6d0d56190	549	pcb->rcv_ann_wnd = pcb->rcv_wnd;
samdanbury	6:37b6d0d56190	550	return new_right_edge - pcb->rcv_ann_right_edge;
samdanbury	6:37b6d0d56190	551	} else {
samdanbury	6:37b6d0d56190	552	if (TCP_SEQ_GT(pcb->rcv_nxt, pcb->rcv_ann_right_edge)) {
samdanbury	6:37b6d0d56190	553	/* Can happen due to other end sending out of advertised window,
samdanbury	6:37b6d0d56190	554	* but within actual available (but not yet advertised) window */
samdanbury	6:37b6d0d56190	555	pcb->rcv_ann_wnd = 0;
samdanbury	6:37b6d0d56190	556	} else {
samdanbury	6:37b6d0d56190	557	/* keep the right edge of window constant */
samdanbury	6:37b6d0d56190	558	u32_t new_rcv_ann_wnd = pcb->rcv_ann_right_edge - pcb->rcv_nxt;
samdanbury	6:37b6d0d56190	559	LWIP_ASSERT("new_rcv_ann_wnd <= 0xffff", new_rcv_ann_wnd <= 0xffff);
samdanbury	6:37b6d0d56190	560	pcb->rcv_ann_wnd = (u16_t)new_rcv_ann_wnd;
samdanbury	6:37b6d0d56190	561	}
samdanbury	6:37b6d0d56190	562	return 0;
samdanbury	6:37b6d0d56190	563	}
samdanbury	6:37b6d0d56190	564	}
samdanbury	6:37b6d0d56190	565
samdanbury	6:37b6d0d56190	566	/**
samdanbury	6:37b6d0d56190	567	* This function should be called by the application when it has
samdanbury	6:37b6d0d56190	568	* processed the data. The purpose is to advertise a larger window
samdanbury	6:37b6d0d56190	569	* when the data has been processed.
samdanbury	6:37b6d0d56190	570	*
samdanbury	6:37b6d0d56190	571	* @param pcb the tcp_pcb for which data is read
samdanbury	6:37b6d0d56190	572	* @param len the amount of bytes that have been read by the application
samdanbury	6:37b6d0d56190	573	*/
samdanbury	6:37b6d0d56190	574	void
samdanbury	6:37b6d0d56190	575	tcp_recved(struct tcp_pcb *pcb, u16_t len)
samdanbury	6:37b6d0d56190	576	{
samdanbury	6:37b6d0d56190	577	int wnd_inflation;
samdanbury	6:37b6d0d56190	578
samdanbury	6:37b6d0d56190	579	LWIP_ASSERT("tcp_recved: len would wrap rcv_wnd\n",
samdanbury	6:37b6d0d56190	580	len <= 0xffff - pcb->rcv_wnd );
samdanbury	6:37b6d0d56190	581
samdanbury	6:37b6d0d56190	582	pcb->rcv_wnd += len;
samdanbury	6:37b6d0d56190	583	if (pcb->rcv_wnd > TCP_WND) {
samdanbury	6:37b6d0d56190	584	pcb->rcv_wnd = TCP_WND;
samdanbury	6:37b6d0d56190	585	}
samdanbury	6:37b6d0d56190	586
samdanbury	6:37b6d0d56190	587	wnd_inflation = tcp_update_rcv_ann_wnd(pcb);
samdanbury	6:37b6d0d56190	588
samdanbury	6:37b6d0d56190	589	/* If the change in the right edge of window is significant (default
samdanbury	6:37b6d0d56190	590	* watermark is TCP_WND/4), then send an explicit update now.
samdanbury	6:37b6d0d56190	591	* Otherwise wait for a packet to be sent in the normal course of
samdanbury	6:37b6d0d56190	592	* events (or more window to be available later) */
samdanbury	6:37b6d0d56190	593	if (wnd_inflation >= TCP_WND_UPDATE_THRESHOLD) {
samdanbury	6:37b6d0d56190	594	tcp_ack_now(pcb);
samdanbury	6:37b6d0d56190	595	tcp_output(pcb);
samdanbury	6:37b6d0d56190	596	}
samdanbury	6:37b6d0d56190	597
samdanbury	6:37b6d0d56190	598	LWIP_DEBUGF(TCP_DEBUG, ("tcp_recved: recveived %"U16_F" bytes, wnd %"U16_F" (%"U16_F").\n",
samdanbury	6:37b6d0d56190	599	len, pcb->rcv_wnd, TCP_WND - pcb->rcv_wnd));
samdanbury	6:37b6d0d56190	600	}
samdanbury	6:37b6d0d56190	601
samdanbury	6:37b6d0d56190	602	/**
samdanbury	6:37b6d0d56190	603	* A nastly hack featuring 'goto' statements that allocates a
samdanbury	6:37b6d0d56190	604	* new TCP local port.
samdanbury	6:37b6d0d56190	605	*
samdanbury	6:37b6d0d56190	606	* @return a new (free) local TCP port number
samdanbury	6:37b6d0d56190	607	*/
samdanbury	6:37b6d0d56190	608	static u16_t
samdanbury	6:37b6d0d56190	609	tcp_new_port(void)
samdanbury	6:37b6d0d56190	610	{
samdanbury	6:37b6d0d56190	611	int i;
samdanbury	6:37b6d0d56190	612	struct tcp_pcb *pcb;
samdanbury	6:37b6d0d56190	613	#ifndef TCP_LOCAL_PORT_RANGE_START
samdanbury	6:37b6d0d56190	614	/* From http://www.iana.org/assignments/port-numbers:
samdanbury	6:37b6d0d56190	615	"The Dynamic and/or Private Ports are those from 49152 through 65535" */
samdanbury	6:37b6d0d56190	616	#define TCP_LOCAL_PORT_RANGE_START 0xc000
samdanbury	6:37b6d0d56190	617	#define TCP_LOCAL_PORT_RANGE_END 0xffff
samdanbury	6:37b6d0d56190	618	#endif
samdanbury	6:37b6d0d56190	619	static u16_t port = TCP_LOCAL_PORT_RANGE_START;
samdanbury	6:37b6d0d56190	620
samdanbury	6:37b6d0d56190	621	again:
samdanbury	6:37b6d0d56190	622	if (port++ >= TCP_LOCAL_PORT_RANGE_END) {
samdanbury	6:37b6d0d56190	623	port = TCP_LOCAL_PORT_RANGE_START;
samdanbury	6:37b6d0d56190	624	}
samdanbury	6:37b6d0d56190	625	/* Check all PCB lists. */
samdanbury	6:37b6d0d56190	626	for (i = 0; i < NUM_TCP_PCB_LISTS; i++) {
samdanbury	6:37b6d0d56190	627	for(pcb = *tcp_pcb_lists[i]; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	628	if (pcb->local_port == port) {
samdanbury	6:37b6d0d56190	629	goto again;
samdanbury	6:37b6d0d56190	630	}
samdanbury	6:37b6d0d56190	631	}
samdanbury	6:37b6d0d56190	632	}
samdanbury	6:37b6d0d56190	633	return port;
samdanbury	6:37b6d0d56190	634	}
samdanbury	6:37b6d0d56190	635
samdanbury	6:37b6d0d56190	636	/**
samdanbury	6:37b6d0d56190	637	* Connects to another host. The function given as the "connected"
samdanbury	6:37b6d0d56190	638	* argument will be called when the connection has been established.
samdanbury	6:37b6d0d56190	639	*
samdanbury	6:37b6d0d56190	640	* @param pcb the tcp_pcb used to establish the connection
samdanbury	6:37b6d0d56190	641	* @param ipaddr the remote ip address to connect to
samdanbury	6:37b6d0d56190	642	* @param port the remote tcp port to connect to
samdanbury	6:37b6d0d56190	643	* @param connected callback function to call when connected (or on error)
samdanbury	6:37b6d0d56190	644	* @return ERR_VAL if invalid arguments are given
samdanbury	6:37b6d0d56190	645	* ERR_OK if connect request has been sent
samdanbury	6:37b6d0d56190	646	* other err_t values if connect request couldn't be sent
samdanbury	6:37b6d0d56190	647	*/
samdanbury	6:37b6d0d56190	648	err_t
samdanbury	6:37b6d0d56190	649	tcp_connect(struct tcp_pcb pcb, ip_addr_t ipaddr, u16_t port,
samdanbury	6:37b6d0d56190	650	tcp_connected_fn connected)
samdanbury	6:37b6d0d56190	651	{
samdanbury	6:37b6d0d56190	652	err_t ret;
samdanbury	6:37b6d0d56190	653	u32_t iss;
samdanbury	6:37b6d0d56190	654	u16_t old_local_port;
samdanbury	6:37b6d0d56190	655
samdanbury	6:37b6d0d56190	656	LWIP_ERROR("tcp_connect: can only connect from state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
samdanbury	6:37b6d0d56190	657
samdanbury	6:37b6d0d56190	658	LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect to port %"U16_F"\n", port));
samdanbury	6:37b6d0d56190	659	if (ipaddr != NULL) {
samdanbury	6:37b6d0d56190	660	pcb->remote_ip = *ipaddr;
samdanbury	6:37b6d0d56190	661	} else {
samdanbury	6:37b6d0d56190	662	return ERR_VAL;
samdanbury	6:37b6d0d56190	663	}
samdanbury	6:37b6d0d56190	664	pcb->remote_port = port;
samdanbury	6:37b6d0d56190	665
samdanbury	6:37b6d0d56190	666	/* check if we have a route to the remote host */
samdanbury	6:37b6d0d56190	667	if (ip_addr_isany(&(pcb->local_ip))) {
samdanbury	6:37b6d0d56190	668	/* no local IP address set, yet. */
samdanbury	6:37b6d0d56190	669	struct netif *netif = ip_route(&(pcb->remote_ip));
samdanbury	6:37b6d0d56190	670	if (netif == NULL) {
samdanbury	6:37b6d0d56190	671	/* Don't even try to send a SYN packet if we have no route
samdanbury	6:37b6d0d56190	672	since that will fail. */
samdanbury	6:37b6d0d56190	673	return ERR_RTE;
samdanbury	6:37b6d0d56190	674	}
samdanbury	6:37b6d0d56190	675	/* Use the netif's IP address as local address. */
samdanbury	6:37b6d0d56190	676	ip_addr_copy(pcb->local_ip, netif->ip_addr);
samdanbury	6:37b6d0d56190	677	}
samdanbury	6:37b6d0d56190	678
samdanbury	6:37b6d0d56190	679	old_local_port = pcb->local_port;
samdanbury	6:37b6d0d56190	680	if (pcb->local_port == 0) {
samdanbury	6:37b6d0d56190	681	pcb->local_port = tcp_new_port();
samdanbury	6:37b6d0d56190	682	}
samdanbury	6:37b6d0d56190	683	#if SO_REUSE
samdanbury	6:37b6d0d56190	684	if ((pcb->so_options & SOF_REUSEADDR) != 0) {
samdanbury	6:37b6d0d56190	685	/* Since SOF_REUSEADDR allows reusing a local address, we have to make sure
samdanbury	6:37b6d0d56190	686	now that the 5-tuple is unique. */
samdanbury	6:37b6d0d56190	687	struct tcp_pcb *cpcb;
samdanbury	6:37b6d0d56190	688	int i;
samdanbury	6:37b6d0d56190	689	/* Don't check listen- and bound-PCBs, check active- and TIME-WAIT PCBs. */
samdanbury	6:37b6d0d56190	690	for (i = 2; i < NUM_TCP_PCB_LISTS; i++) {
samdanbury	6:37b6d0d56190	691	for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
samdanbury	6:37b6d0d56190	692	if ((cpcb->local_port == pcb->local_port) &&
samdanbury	6:37b6d0d56190	693	(cpcb->remote_port == port) &&
samdanbury	6:37b6d0d56190	694	ip_addr_cmp(&cpcb->local_ip, &pcb->local_ip) &&
samdanbury	6:37b6d0d56190	695	ip_addr_cmp(&cpcb->remote_ip, ipaddr)) {
samdanbury	6:37b6d0d56190	696	/* linux returns EISCONN here, but ERR_USE should be OK for us */
samdanbury	6:37b6d0d56190	697	return ERR_USE;
samdanbury	6:37b6d0d56190	698	}
samdanbury	6:37b6d0d56190	699	}
samdanbury	6:37b6d0d56190	700	}
samdanbury	6:37b6d0d56190	701	}
samdanbury	6:37b6d0d56190	702	#endif /* SO_REUSE */
samdanbury	6:37b6d0d56190	703	iss = tcp_next_iss();
samdanbury	6:37b6d0d56190	704	pcb->rcv_nxt = 0;
samdanbury	6:37b6d0d56190	705	pcb->snd_nxt = iss;
samdanbury	6:37b6d0d56190	706	pcb->lastack = iss - 1;
samdanbury	6:37b6d0d56190	707	pcb->snd_lbb = iss - 1;
samdanbury	6:37b6d0d56190	708	pcb->rcv_wnd = TCP_WND;
samdanbury	6:37b6d0d56190	709	pcb->rcv_ann_wnd = TCP_WND;
samdanbury	6:37b6d0d56190	710	pcb->rcv_ann_right_edge = pcb->rcv_nxt;
samdanbury	6:37b6d0d56190	711	pcb->snd_wnd = TCP_WND;
samdanbury	6:37b6d0d56190	712	/* As initial send MSS, we use TCP_MSS but limit it to 536.
samdanbury	6:37b6d0d56190	713	The send MSS is updated when an MSS option is received. */
samdanbury	6:37b6d0d56190	714	pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
samdanbury	6:37b6d0d56190	715	#if TCP_CALCULATE_EFF_SEND_MSS
samdanbury	6:37b6d0d56190	716	pcb->mss = tcp_eff_send_mss(pcb->mss, ipaddr);
samdanbury	6:37b6d0d56190	717	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
samdanbury	6:37b6d0d56190	718	pcb->cwnd = 1;
samdanbury	6:37b6d0d56190	719	pcb->ssthresh = pcb->mss * 10;
samdanbury	6:37b6d0d56190	720	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	721	pcb->connected = connected;
samdanbury	6:37b6d0d56190	722	#else /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	723	LWIP_UNUSED_ARG(connected);
samdanbury	6:37b6d0d56190	724	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	725
samdanbury	6:37b6d0d56190	726	/* Send a SYN together with the MSS option. */
samdanbury	6:37b6d0d56190	727	ret = tcp_enqueue_flags(pcb, TCP_SYN);
samdanbury	6:37b6d0d56190	728	if (ret == ERR_OK) {
samdanbury	6:37b6d0d56190	729	/* SYN segment was enqueued, changed the pcbs state now */
samdanbury	6:37b6d0d56190	730	pcb->state = SYN_SENT;
samdanbury	6:37b6d0d56190	731	if (old_local_port != 0) {
samdanbury	6:37b6d0d56190	732	TCP_RMV(&tcp_bound_pcbs, pcb);
samdanbury	6:37b6d0d56190	733	}
samdanbury	6:37b6d0d56190	734	TCP_REG(&tcp_active_pcbs, pcb);
samdanbury	6:37b6d0d56190	735	snmp_inc_tcpactiveopens();
samdanbury	6:37b6d0d56190	736
samdanbury	6:37b6d0d56190	737	tcp_output(pcb);
samdanbury	6:37b6d0d56190	738	}
samdanbury	6:37b6d0d56190	739	return ret;
samdanbury	6:37b6d0d56190	740	}
samdanbury	6:37b6d0d56190	741
samdanbury	6:37b6d0d56190	742	/**
samdanbury	6:37b6d0d56190	743	* Called every 500 ms and implements the retransmission timer and the timer that
samdanbury	6:37b6d0d56190	744	* removes PCBs that have been in TIME-WAIT for enough time. It also increments
samdanbury	6:37b6d0d56190	745	* various timers such as the inactivity timer in each PCB.
samdanbury	6:37b6d0d56190	746	*
samdanbury	6:37b6d0d56190	747	* Automatically called from tcp_tmr().
samdanbury	6:37b6d0d56190	748	*/
samdanbury	6:37b6d0d56190	749	void
samdanbury	6:37b6d0d56190	750	tcp_slowtmr(void)
samdanbury	6:37b6d0d56190	751	{
samdanbury	6:37b6d0d56190	752	struct tcp_pcb pcb, prev;
samdanbury	6:37b6d0d56190	753	u16_t eff_wnd;
samdanbury	6:37b6d0d56190	754	u8_t pcb_remove; /* flag if a PCB should be removed */
samdanbury	6:37b6d0d56190	755	u8_t pcb_reset; /* flag if a RST should be sent when removing */
samdanbury	6:37b6d0d56190	756	err_t err;
samdanbury	6:37b6d0d56190	757
samdanbury	6:37b6d0d56190	758	err = ERR_OK;
samdanbury	6:37b6d0d56190	759
samdanbury	6:37b6d0d56190	760	++tcp_ticks;
samdanbury	6:37b6d0d56190	761
samdanbury	6:37b6d0d56190	762	/* Steps through all of the active PCBs. */
samdanbury	6:37b6d0d56190	763	prev = NULL;
samdanbury	6:37b6d0d56190	764	pcb = tcp_active_pcbs;
samdanbury	6:37b6d0d56190	765	if (pcb == NULL) {
samdanbury	6:37b6d0d56190	766	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: no active pcbs\n"));
samdanbury	6:37b6d0d56190	767	}
samdanbury	6:37b6d0d56190	768	while (pcb != NULL) {
samdanbury	6:37b6d0d56190	769	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: processing active pcb\n"));
samdanbury	6:37b6d0d56190	770	LWIP_ASSERT("tcp_slowtmr: active pcb->state != CLOSED\n", pcb->state != CLOSED);
samdanbury	6:37b6d0d56190	771	LWIP_ASSERT("tcp_slowtmr: active pcb->state != LISTEN\n", pcb->state != LISTEN);
samdanbury	6:37b6d0d56190	772	LWIP_ASSERT("tcp_slowtmr: active pcb->state != TIME-WAIT\n", pcb->state != TIME_WAIT);
samdanbury	6:37b6d0d56190	773
samdanbury	6:37b6d0d56190	774	pcb_remove = 0;
samdanbury	6:37b6d0d56190	775	pcb_reset = 0;
samdanbury	6:37b6d0d56190	776
samdanbury	6:37b6d0d56190	777	if (pcb->state == SYN_SENT && pcb->nrtx == TCP_SYNMAXRTX) {
samdanbury	6:37b6d0d56190	778	++pcb_remove;
samdanbury	6:37b6d0d56190	779	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max SYN retries reached\n"));
samdanbury	6:37b6d0d56190	780	}
samdanbury	6:37b6d0d56190	781	else if (pcb->nrtx == TCP_MAXRTX) {
samdanbury	6:37b6d0d56190	782	++pcb_remove;
samdanbury	6:37b6d0d56190	783	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max DATA retries reached\n"));
samdanbury	6:37b6d0d56190	784	} else {
samdanbury	6:37b6d0d56190	785	if (pcb->persist_backoff > 0) {
samdanbury	6:37b6d0d56190	786	/* If snd_wnd is zero, use persist timer to send 1 byte probes
samdanbury	6:37b6d0d56190	787	* instead of using the standard retransmission mechanism. */
samdanbury	6:37b6d0d56190	788	pcb->persist_cnt++;
samdanbury	6:37b6d0d56190	789	if (pcb->persist_cnt >= tcp_persist_backoff[pcb->persist_backoff-1]) {
samdanbury	6:37b6d0d56190	790	pcb->persist_cnt = 0;
samdanbury	6:37b6d0d56190	791	if (pcb->persist_backoff < sizeof(tcp_persist_backoff)) {
samdanbury	6:37b6d0d56190	792	pcb->persist_backoff++;
samdanbury	6:37b6d0d56190	793	}
samdanbury	6:37b6d0d56190	794	tcp_zero_window_probe(pcb);
samdanbury	6:37b6d0d56190	795	}
samdanbury	6:37b6d0d56190	796	} else {
samdanbury	6:37b6d0d56190	797	/* Increase the retransmission timer if it is running */
samdanbury	6:37b6d0d56190	798	if(pcb->rtime >= 0)
samdanbury	6:37b6d0d56190	799	++pcb->rtime;
samdanbury	6:37b6d0d56190	800
samdanbury	6:37b6d0d56190	801	if (pcb->unacked != NULL && pcb->rtime >= pcb->rto) {
samdanbury	6:37b6d0d56190	802	/* Time for a retransmission. */
samdanbury	6:37b6d0d56190	803	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_slowtmr: rtime %"S16_F
samdanbury	6:37b6d0d56190	804	" pcb->rto %"S16_F"\n",
samdanbury	6:37b6d0d56190	805	pcb->rtime, pcb->rto));
samdanbury	6:37b6d0d56190	806
samdanbury	6:37b6d0d56190	807	/* Double retransmission time-out unless we are trying to
samdanbury	6:37b6d0d56190	808	* connect to somebody (i.e., we are in SYN_SENT). */
samdanbury	6:37b6d0d56190	809	if (pcb->state != SYN_SENT) {
samdanbury	6:37b6d0d56190	810	pcb->rto = ((pcb->sa >> 3) + pcb->sv) << tcp_backoff[pcb->nrtx];
samdanbury	6:37b6d0d56190	811	}
samdanbury	6:37b6d0d56190	812
samdanbury	6:37b6d0d56190	813	/* Reset the retransmission timer. */
samdanbury	6:37b6d0d56190	814	pcb->rtime = 0;
samdanbury	6:37b6d0d56190	815
samdanbury	6:37b6d0d56190	816	/* Reduce congestion window and ssthresh. */
samdanbury	6:37b6d0d56190	817	eff_wnd = LWIP_MIN(pcb->cwnd, pcb->snd_wnd);
samdanbury	6:37b6d0d56190	818	pcb->ssthresh = eff_wnd >> 1;
samdanbury	6:37b6d0d56190	819	if (pcb->ssthresh < (pcb->mss << 1)) {
samdanbury	6:37b6d0d56190	820	pcb->ssthresh = (pcb->mss << 1);
samdanbury	6:37b6d0d56190	821	}
samdanbury	6:37b6d0d56190	822	pcb->cwnd = pcb->mss;
samdanbury	6:37b6d0d56190	823	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: cwnd %"U16_F
samdanbury	6:37b6d0d56190	824	" ssthresh %"U16_F"\n",
samdanbury	6:37b6d0d56190	825	pcb->cwnd, pcb->ssthresh));
samdanbury	6:37b6d0d56190	826
samdanbury	6:37b6d0d56190	827	/* The following needs to be called AFTER cwnd is set to one
samdanbury	6:37b6d0d56190	828	mss - STJ */
samdanbury	6:37b6d0d56190	829	tcp_rexmit_rto(pcb);
samdanbury	6:37b6d0d56190	830	}
samdanbury	6:37b6d0d56190	831	}
samdanbury	6:37b6d0d56190	832	}
samdanbury	6:37b6d0d56190	833	/* Check if this PCB has stayed too long in FIN-WAIT-2 */
samdanbury	6:37b6d0d56190	834	if (pcb->state == FIN_WAIT_2) {
samdanbury	6:37b6d0d56190	835	if ((u32_t)(tcp_ticks - pcb->tmr) >
samdanbury	6:37b6d0d56190	836	TCP_FIN_WAIT_TIMEOUT / TCP_SLOW_INTERVAL) {
samdanbury	6:37b6d0d56190	837	++pcb_remove;
samdanbury	6:37b6d0d56190	838	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in FIN-WAIT-2\n"));
samdanbury	6:37b6d0d56190	839	}
samdanbury	6:37b6d0d56190	840	}
samdanbury	6:37b6d0d56190	841
samdanbury	6:37b6d0d56190	842	/* Check if KEEPALIVE should be sent */
samdanbury	6:37b6d0d56190	843	if((pcb->so_options & SOF_KEEPALIVE) &&
samdanbury	6:37b6d0d56190	844	((pcb->state == ESTABLISHED) \|\|
samdanbury	6:37b6d0d56190	845	(pcb->state == CLOSE_WAIT))) {
samdanbury	6:37b6d0d56190	846	#if LWIP_TCP_KEEPALIVE
samdanbury	6:37b6d0d56190	847	if((u32_t)(tcp_ticks - pcb->tmr) >
samdanbury	6:37b6d0d56190	848	(pcb->keep_idle + (pcb->keep_cnt*pcb->keep_intvl))
samdanbury	6:37b6d0d56190	849	/ TCP_SLOW_INTERVAL)
samdanbury	6:37b6d0d56190	850	#else
samdanbury	6:37b6d0d56190	851	if((u32_t)(tcp_ticks - pcb->tmr) >
samdanbury	6:37b6d0d56190	852	(pcb->keep_idle + TCP_MAXIDLE) / TCP_SLOW_INTERVAL)
samdanbury	6:37b6d0d56190	853	#endif /* LWIP_TCP_KEEPALIVE */
samdanbury	6:37b6d0d56190	854	{
samdanbury	6:37b6d0d56190	855	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: KEEPALIVE timeout. Aborting connection to %"U16_F".%"U16_F".%"U16_F".%"U16_F".\n",
samdanbury	6:37b6d0d56190	856	ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
samdanbury	6:37b6d0d56190	857	ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
samdanbury	6:37b6d0d56190	858
samdanbury	6:37b6d0d56190	859	++pcb_remove;
samdanbury	6:37b6d0d56190	860	++pcb_reset;
samdanbury	6:37b6d0d56190	861	}
samdanbury	6:37b6d0d56190	862	#if LWIP_TCP_KEEPALIVE
samdanbury	6:37b6d0d56190	863	else if((u32_t)(tcp_ticks - pcb->tmr) >
samdanbury	6:37b6d0d56190	864	(pcb->keep_idle + pcb->keep_cnt_sent * pcb->keep_intvl)
samdanbury	6:37b6d0d56190	865	/ TCP_SLOW_INTERVAL)
samdanbury	6:37b6d0d56190	866	#else
samdanbury	6:37b6d0d56190	867	else if((u32_t)(tcp_ticks - pcb->tmr) >
samdanbury	6:37b6d0d56190	868	(pcb->keep_idle + pcb->keep_cnt_sent * TCP_KEEPINTVL_DEFAULT)
samdanbury	6:37b6d0d56190	869	/ TCP_SLOW_INTERVAL)
samdanbury	6:37b6d0d56190	870	#endif /* LWIP_TCP_KEEPALIVE */
samdanbury	6:37b6d0d56190	871	{
samdanbury	6:37b6d0d56190	872	tcp_keepalive(pcb);
samdanbury	6:37b6d0d56190	873	pcb->keep_cnt_sent++;
samdanbury	6:37b6d0d56190	874	}
samdanbury	6:37b6d0d56190	875	}
samdanbury	6:37b6d0d56190	876
samdanbury	6:37b6d0d56190	877	/* If this PCB has queued out of sequence data, but has been
samdanbury	6:37b6d0d56190	878	inactive for too long, will drop the data (it will eventually
samdanbury	6:37b6d0d56190	879	be retransmitted). */
samdanbury	6:37b6d0d56190	880	#if TCP_QUEUE_OOSEQ
samdanbury	6:37b6d0d56190	881	if (pcb->ooseq != NULL &&
samdanbury	6:37b6d0d56190	882	(u32_t)tcp_ticks - pcb->tmr >= pcb->rto * TCP_OOSEQ_TIMEOUT) {
samdanbury	6:37b6d0d56190	883	tcp_segs_free(pcb->ooseq);
samdanbury	6:37b6d0d56190	884	pcb->ooseq = NULL;
samdanbury	6:37b6d0d56190	885	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: dropping OOSEQ queued data\n"));
samdanbury	6:37b6d0d56190	886	}
samdanbury	6:37b6d0d56190	887	#endif /* TCP_QUEUE_OOSEQ */
samdanbury	6:37b6d0d56190	888
samdanbury	6:37b6d0d56190	889	/* Check if this PCB has stayed too long in SYN-RCVD */
samdanbury	6:37b6d0d56190	890	if (pcb->state == SYN_RCVD) {
samdanbury	6:37b6d0d56190	891	if ((u32_t)(tcp_ticks - pcb->tmr) >
samdanbury	6:37b6d0d56190	892	TCP_SYN_RCVD_TIMEOUT / TCP_SLOW_INTERVAL) {
samdanbury	6:37b6d0d56190	893	++pcb_remove;
samdanbury	6:37b6d0d56190	894	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in SYN-RCVD\n"));
samdanbury	6:37b6d0d56190	895	}
samdanbury	6:37b6d0d56190	896	}
samdanbury	6:37b6d0d56190	897
samdanbury	6:37b6d0d56190	898	/* Check if this PCB has stayed too long in LAST-ACK */
samdanbury	6:37b6d0d56190	899	if (pcb->state == LAST_ACK) {
samdanbury	6:37b6d0d56190	900	if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
samdanbury	6:37b6d0d56190	901	++pcb_remove;
samdanbury	6:37b6d0d56190	902	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in LAST-ACK\n"));
samdanbury	6:37b6d0d56190	903	}
samdanbury	6:37b6d0d56190	904	}
samdanbury	6:37b6d0d56190	905
samdanbury	6:37b6d0d56190	906	/* If the PCB should be removed, do it. */
samdanbury	6:37b6d0d56190	907	if (pcb_remove) {
samdanbury	6:37b6d0d56190	908	struct tcp_pcb *pcb2;
samdanbury	6:37b6d0d56190	909	tcp_pcb_purge(pcb);
samdanbury	6:37b6d0d56190	910	/* Remove PCB from tcp_active_pcbs list. */
samdanbury	6:37b6d0d56190	911	if (prev != NULL) {
samdanbury	6:37b6d0d56190	912	LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_active_pcbs", pcb != tcp_active_pcbs);
samdanbury	6:37b6d0d56190	913	prev->next = pcb->next;
samdanbury	6:37b6d0d56190	914	} else {
samdanbury	6:37b6d0d56190	915	/* This PCB was the first. */
samdanbury	6:37b6d0d56190	916	LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_active_pcbs", tcp_active_pcbs == pcb);
samdanbury	6:37b6d0d56190	917	tcp_active_pcbs = pcb->next;
samdanbury	6:37b6d0d56190	918	}
samdanbury	6:37b6d0d56190	919
samdanbury	6:37b6d0d56190	920	TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_ABRT);
samdanbury	6:37b6d0d56190	921	if (pcb_reset) {
samdanbury	6:37b6d0d56190	922	tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
samdanbury	6:37b6d0d56190	923	pcb->local_port, pcb->remote_port);
samdanbury	6:37b6d0d56190	924	}
samdanbury	6:37b6d0d56190	925
samdanbury	6:37b6d0d56190	926	pcb2 = pcb;
samdanbury	6:37b6d0d56190	927	pcb = pcb->next;
samdanbury	6:37b6d0d56190	928	memp_free(MEMP_TCP_PCB, pcb2);
samdanbury	6:37b6d0d56190	929	} else {
samdanbury	6:37b6d0d56190	930	/* get the 'next' element now and work with 'prev' below (in case of abort) */
samdanbury	6:37b6d0d56190	931	prev = pcb;
samdanbury	6:37b6d0d56190	932	pcb = pcb->next;
samdanbury	6:37b6d0d56190	933
samdanbury	6:37b6d0d56190	934	/* We check if we should poll the connection. */
samdanbury	6:37b6d0d56190	935	++prev->polltmr;
samdanbury	6:37b6d0d56190	936	if (prev->polltmr >= prev->pollinterval) {
samdanbury	6:37b6d0d56190	937	prev->polltmr = 0;
samdanbury	6:37b6d0d56190	938	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: polling application\n"));
samdanbury	6:37b6d0d56190	939	TCP_EVENT_POLL(prev, err);
samdanbury	6:37b6d0d56190	940	/* if err == ERR_ABRT, 'prev' is already deallocated */
samdanbury	6:37b6d0d56190	941	if (err == ERR_OK) {
samdanbury	6:37b6d0d56190	942	tcp_output(prev);
samdanbury	6:37b6d0d56190	943	}
samdanbury	6:37b6d0d56190	944	}
samdanbury	6:37b6d0d56190	945	}
samdanbury	6:37b6d0d56190	946	}
samdanbury	6:37b6d0d56190	947
samdanbury	6:37b6d0d56190	948
samdanbury	6:37b6d0d56190	949	/* Steps through all of the TIME-WAIT PCBs. */
samdanbury	6:37b6d0d56190	950	prev = NULL;
samdanbury	6:37b6d0d56190	951	pcb = tcp_tw_pcbs;
samdanbury	6:37b6d0d56190	952	while (pcb != NULL) {
samdanbury	6:37b6d0d56190	953	LWIP_ASSERT("tcp_slowtmr: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
samdanbury	6:37b6d0d56190	954	pcb_remove = 0;
samdanbury	6:37b6d0d56190	955
samdanbury	6:37b6d0d56190	956	/* Check if this PCB has stayed long enough in TIME-WAIT */
samdanbury	6:37b6d0d56190	957	if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
samdanbury	6:37b6d0d56190	958	++pcb_remove;
samdanbury	6:37b6d0d56190	959	}
samdanbury	6:37b6d0d56190	960
samdanbury	6:37b6d0d56190	961
samdanbury	6:37b6d0d56190	962
samdanbury	6:37b6d0d56190	963	/* If the PCB should be removed, do it. */
samdanbury	6:37b6d0d56190	964	if (pcb_remove) {
samdanbury	6:37b6d0d56190	965	struct tcp_pcb *pcb2;
samdanbury	6:37b6d0d56190	966	tcp_pcb_purge(pcb);
samdanbury	6:37b6d0d56190	967	/* Remove PCB from tcp_tw_pcbs list. */
samdanbury	6:37b6d0d56190	968	if (prev != NULL) {
samdanbury	6:37b6d0d56190	969	LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_tw_pcbs", pcb != tcp_tw_pcbs);
samdanbury	6:37b6d0d56190	970	prev->next = pcb->next;
samdanbury	6:37b6d0d56190	971	} else {
samdanbury	6:37b6d0d56190	972	/* This PCB was the first. */
samdanbury	6:37b6d0d56190	973	LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_tw_pcbs", tcp_tw_pcbs == pcb);
samdanbury	6:37b6d0d56190	974	tcp_tw_pcbs = pcb->next;
samdanbury	6:37b6d0d56190	975	}
samdanbury	6:37b6d0d56190	976	pcb2 = pcb;
samdanbury	6:37b6d0d56190	977	pcb = pcb->next;
samdanbury	6:37b6d0d56190	978	memp_free(MEMP_TCP_PCB, pcb2);
samdanbury	6:37b6d0d56190	979	} else {
samdanbury	6:37b6d0d56190	980	prev = pcb;
samdanbury	6:37b6d0d56190	981	pcb = pcb->next;
samdanbury	6:37b6d0d56190	982	}
samdanbury	6:37b6d0d56190	983	}
samdanbury	6:37b6d0d56190	984	}
samdanbury	6:37b6d0d56190	985
samdanbury	6:37b6d0d56190	986	/**
samdanbury	6:37b6d0d56190	987	* Is called every TCP_FAST_INTERVAL (250 ms) and process data previously
samdanbury	6:37b6d0d56190	988	* "refused" by upper layer (application) and sends delayed ACKs.
samdanbury	6:37b6d0d56190	989	*
samdanbury	6:37b6d0d56190	990	* Automatically called from tcp_tmr().
samdanbury	6:37b6d0d56190	991	*/
samdanbury	6:37b6d0d56190	992	void
samdanbury	6:37b6d0d56190	993	tcp_fasttmr(void)
samdanbury	6:37b6d0d56190	994	{
samdanbury	6:37b6d0d56190	995	struct tcp_pcb *pcb = tcp_active_pcbs;
samdanbury	6:37b6d0d56190	996
samdanbury	6:37b6d0d56190	997	while(pcb != NULL) {
samdanbury	6:37b6d0d56190	998	struct tcp_pcb *next = pcb->next;
samdanbury	6:37b6d0d56190	999	/* If there is data which was previously "refused" by upper layer */
samdanbury	6:37b6d0d56190	1000	if (pcb->refused_data != NULL) {
samdanbury	6:37b6d0d56190	1001	/* Notify again application with data previously received. */
samdanbury	6:37b6d0d56190	1002	err_t err;
samdanbury	6:37b6d0d56190	1003	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_fasttmr: notify kept packet\n"));
samdanbury	6:37b6d0d56190	1004	TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
samdanbury	6:37b6d0d56190	1005	if (err == ERR_OK) {
samdanbury	6:37b6d0d56190	1006	pcb->refused_data = NULL;
samdanbury	6:37b6d0d56190	1007	} else if (err == ERR_ABRT) {
samdanbury	6:37b6d0d56190	1008	/* if err == ERR_ABRT, 'pcb' is already deallocated */
samdanbury	6:37b6d0d56190	1009	pcb = NULL;
samdanbury	6:37b6d0d56190	1010	}
samdanbury	6:37b6d0d56190	1011	}
samdanbury	6:37b6d0d56190	1012
samdanbury	6:37b6d0d56190	1013	/* send delayed ACKs */
samdanbury	6:37b6d0d56190	1014	if (pcb && (pcb->flags & TF_ACK_DELAY)) {
samdanbury	6:37b6d0d56190	1015	LWIP_DEBUGF(TCP_DEBUG, ("tcp_fasttmr: delayed ACK\n"));
samdanbury	6:37b6d0d56190	1016	tcp_ack_now(pcb);
samdanbury	6:37b6d0d56190	1017	tcp_output(pcb);
samdanbury	6:37b6d0d56190	1018	pcb->flags &= ~(TF_ACK_DELAY \| TF_ACK_NOW);
samdanbury	6:37b6d0d56190	1019	}
samdanbury	6:37b6d0d56190	1020
samdanbury	6:37b6d0d56190	1021	pcb = next;
samdanbury	6:37b6d0d56190	1022	}
samdanbury	6:37b6d0d56190	1023	}
samdanbury	6:37b6d0d56190	1024
samdanbury	6:37b6d0d56190	1025	/**
samdanbury	6:37b6d0d56190	1026	* Deallocates a list of TCP segments (tcp_seg structures).
samdanbury	6:37b6d0d56190	1027	*
samdanbury	6:37b6d0d56190	1028	* @param seg tcp_seg list of TCP segments to free
samdanbury	6:37b6d0d56190	1029	*/
samdanbury	6:37b6d0d56190	1030	void
samdanbury	6:37b6d0d56190	1031	tcp_segs_free(struct tcp_seg *seg)
samdanbury	6:37b6d0d56190	1032	{
samdanbury	6:37b6d0d56190	1033	while (seg != NULL) {
samdanbury	6:37b6d0d56190	1034	struct tcp_seg *next = seg->next;
samdanbury	6:37b6d0d56190	1035	tcp_seg_free(seg);
samdanbury	6:37b6d0d56190	1036	seg = next;
samdanbury	6:37b6d0d56190	1037	}
samdanbury	6:37b6d0d56190	1038	}
samdanbury	6:37b6d0d56190	1039
samdanbury	6:37b6d0d56190	1040	/**
samdanbury	6:37b6d0d56190	1041	* Frees a TCP segment (tcp_seg structure).
samdanbury	6:37b6d0d56190	1042	*
samdanbury	6:37b6d0d56190	1043	* @param seg single tcp_seg to free
samdanbury	6:37b6d0d56190	1044	*/
samdanbury	6:37b6d0d56190	1045	void
samdanbury	6:37b6d0d56190	1046	tcp_seg_free(struct tcp_seg *seg)
samdanbury	6:37b6d0d56190	1047	{
samdanbury	6:37b6d0d56190	1048	if (seg != NULL) {
samdanbury	6:37b6d0d56190	1049	if (seg->p != NULL) {
samdanbury	6:37b6d0d56190	1050	pbuf_free(seg->p);
samdanbury	6:37b6d0d56190	1051	#if TCP_DEBUG
samdanbury	6:37b6d0d56190	1052	seg->p = NULL;
samdanbury	6:37b6d0d56190	1053	#endif /* TCP_DEBUG */
samdanbury	6:37b6d0d56190	1054	}
samdanbury	6:37b6d0d56190	1055	memp_free(MEMP_TCP_SEG, seg);
samdanbury	6:37b6d0d56190	1056	}
samdanbury	6:37b6d0d56190	1057	}
samdanbury	6:37b6d0d56190	1058
samdanbury	6:37b6d0d56190	1059	/**
samdanbury	6:37b6d0d56190	1060	* Sets the priority of a connection.
samdanbury	6:37b6d0d56190	1061	*
samdanbury	6:37b6d0d56190	1062	* @param pcb the tcp_pcb to manipulate
samdanbury	6:37b6d0d56190	1063	* @param prio new priority
samdanbury	6:37b6d0d56190	1064	*/
samdanbury	6:37b6d0d56190	1065	void
samdanbury	6:37b6d0d56190	1066	tcp_setprio(struct tcp_pcb *pcb, u8_t prio)
samdanbury	6:37b6d0d56190	1067	{
samdanbury	6:37b6d0d56190	1068	pcb->prio = prio;
samdanbury	6:37b6d0d56190	1069	}
samdanbury	6:37b6d0d56190	1070
samdanbury	6:37b6d0d56190	1071	#if TCP_QUEUE_OOSEQ
samdanbury	6:37b6d0d56190	1072	/**
samdanbury	6:37b6d0d56190	1073	* Returns a copy of the given TCP segment.
samdanbury	6:37b6d0d56190	1074	* The pbuf and data are not copied, only the pointers
samdanbury	6:37b6d0d56190	1075	*
samdanbury	6:37b6d0d56190	1076	* @param seg the old tcp_seg
samdanbury	6:37b6d0d56190	1077	* @return a copy of seg
samdanbury	6:37b6d0d56190	1078	*/
samdanbury	6:37b6d0d56190	1079	struct tcp_seg *
samdanbury	6:37b6d0d56190	1080	tcp_seg_copy(struct tcp_seg *seg)
samdanbury	6:37b6d0d56190	1081	{
samdanbury	6:37b6d0d56190	1082	struct tcp_seg *cseg;
samdanbury	6:37b6d0d56190	1083
samdanbury	6:37b6d0d56190	1084	cseg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG);
samdanbury	6:37b6d0d56190	1085	if (cseg == NULL) {
samdanbury	6:37b6d0d56190	1086	return NULL;
samdanbury	6:37b6d0d56190	1087	}
samdanbury	6:37b6d0d56190	1088	SMEMCPY((u8_t )cseg, (const u8_t )seg, sizeof(struct tcp_seg));
samdanbury	6:37b6d0d56190	1089	pbuf_ref(cseg->p);
samdanbury	6:37b6d0d56190	1090	return cseg;
samdanbury	6:37b6d0d56190	1091	}
samdanbury	6:37b6d0d56190	1092	#endif /* TCP_QUEUE_OOSEQ */
samdanbury	6:37b6d0d56190	1093
samdanbury	6:37b6d0d56190	1094	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	1095	/**
samdanbury	6:37b6d0d56190	1096	* Default receive callback that is called if the user didn't register
samdanbury	6:37b6d0d56190	1097	* a recv callback for the pcb.
samdanbury	6:37b6d0d56190	1098	*/
samdanbury	6:37b6d0d56190	1099	err_t
samdanbury	6:37b6d0d56190	1100	tcp_recv_null(void arg, struct tcp_pcb pcb, struct pbuf *p, err_t err)
samdanbury	6:37b6d0d56190	1101	{
samdanbury	6:37b6d0d56190	1102	LWIP_UNUSED_ARG(arg);
samdanbury	6:37b6d0d56190	1103	if (p != NULL) {
samdanbury	6:37b6d0d56190	1104	tcp_recved(pcb, p->tot_len);
samdanbury	6:37b6d0d56190	1105	pbuf_free(p);
samdanbury	6:37b6d0d56190	1106	} else if (err == ERR_OK) {
samdanbury	6:37b6d0d56190	1107	return tcp_close(pcb);
samdanbury	6:37b6d0d56190	1108	}
samdanbury	6:37b6d0d56190	1109	return ERR_OK;
samdanbury	6:37b6d0d56190	1110	}
samdanbury	6:37b6d0d56190	1111	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	1112
samdanbury	6:37b6d0d56190	1113	/**
samdanbury	6:37b6d0d56190	1114	* Kills the oldest active connection that has lower priority than prio.
samdanbury	6:37b6d0d56190	1115	*
samdanbury	6:37b6d0d56190	1116	* @param prio minimum priority
samdanbury	6:37b6d0d56190	1117	*/
samdanbury	6:37b6d0d56190	1118	static void
samdanbury	6:37b6d0d56190	1119	tcp_kill_prio(u8_t prio)
samdanbury	6:37b6d0d56190	1120	{
samdanbury	6:37b6d0d56190	1121	struct tcp_pcb pcb, inactive;
samdanbury	6:37b6d0d56190	1122	u32_t inactivity;
samdanbury	6:37b6d0d56190	1123	u8_t mprio;
samdanbury	6:37b6d0d56190	1124
samdanbury	6:37b6d0d56190	1125
samdanbury	6:37b6d0d56190	1126	mprio = TCP_PRIO_MAX;
samdanbury	6:37b6d0d56190	1127
samdanbury	6:37b6d0d56190	1128	/* We kill the oldest active connection that has lower priority than prio. */
samdanbury	6:37b6d0d56190	1129	inactivity = 0;
samdanbury	6:37b6d0d56190	1130	inactive = NULL;
samdanbury	6:37b6d0d56190	1131	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1132	if (pcb->prio <= prio &&
samdanbury	6:37b6d0d56190	1133	pcb->prio <= mprio &&
samdanbury	6:37b6d0d56190	1134	(u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
samdanbury	6:37b6d0d56190	1135	inactivity = tcp_ticks - pcb->tmr;
samdanbury	6:37b6d0d56190	1136	inactive = pcb;
samdanbury	6:37b6d0d56190	1137	mprio = pcb->prio;
samdanbury	6:37b6d0d56190	1138	}
samdanbury	6:37b6d0d56190	1139	}
samdanbury	6:37b6d0d56190	1140	if (inactive != NULL) {
samdanbury	6:37b6d0d56190	1141	LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_prio: killing oldest PCB %p (%"S32_F")\n",
samdanbury	6:37b6d0d56190	1142	(void *)inactive, inactivity));
samdanbury	6:37b6d0d56190	1143	tcp_abort(inactive);
samdanbury	6:37b6d0d56190	1144	}
samdanbury	6:37b6d0d56190	1145	}
samdanbury	6:37b6d0d56190	1146
samdanbury	6:37b6d0d56190	1147	/**
samdanbury	6:37b6d0d56190	1148	* Kills the oldest connection that is in TIME_WAIT state.
samdanbury	6:37b6d0d56190	1149	* Called from tcp_alloc() if no more connections are available.
samdanbury	6:37b6d0d56190	1150	*/
samdanbury	6:37b6d0d56190	1151	static void
samdanbury	6:37b6d0d56190	1152	tcp_kill_timewait(void)
samdanbury	6:37b6d0d56190	1153	{
samdanbury	6:37b6d0d56190	1154	struct tcp_pcb pcb, inactive;
samdanbury	6:37b6d0d56190	1155	u32_t inactivity;
samdanbury	6:37b6d0d56190	1156
samdanbury	6:37b6d0d56190	1157	inactivity = 0;
samdanbury	6:37b6d0d56190	1158	inactive = NULL;
samdanbury	6:37b6d0d56190	1159	/* Go through the list of TIME_WAIT pcbs and get the oldest pcb. */
samdanbury	6:37b6d0d56190	1160	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1161	if ((u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
samdanbury	6:37b6d0d56190	1162	inactivity = tcp_ticks - pcb->tmr;
samdanbury	6:37b6d0d56190	1163	inactive = pcb;
samdanbury	6:37b6d0d56190	1164	}
samdanbury	6:37b6d0d56190	1165	}
samdanbury	6:37b6d0d56190	1166	if (inactive != NULL) {
samdanbury	6:37b6d0d56190	1167	LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_timewait: killing oldest TIME-WAIT PCB %p (%"S32_F")\n",
samdanbury	6:37b6d0d56190	1168	(void *)inactive, inactivity));
samdanbury	6:37b6d0d56190	1169	tcp_abort(inactive);
samdanbury	6:37b6d0d56190	1170	}
samdanbury	6:37b6d0d56190	1171	}
samdanbury	6:37b6d0d56190	1172
samdanbury	6:37b6d0d56190	1173	/**
samdanbury	6:37b6d0d56190	1174	* Allocate a new tcp_pcb structure.
samdanbury	6:37b6d0d56190	1175	*
samdanbury	6:37b6d0d56190	1176	* @param prio priority for the new pcb
samdanbury	6:37b6d0d56190	1177	* @return a new tcp_pcb that initially is in state CLOSED
samdanbury	6:37b6d0d56190	1178	*/
samdanbury	6:37b6d0d56190	1179	struct tcp_pcb *
samdanbury	6:37b6d0d56190	1180	tcp_alloc(u8_t prio)
samdanbury	6:37b6d0d56190	1181	{
samdanbury	6:37b6d0d56190	1182	struct tcp_pcb *pcb;
samdanbury	6:37b6d0d56190	1183	u32_t iss;
samdanbury	6:37b6d0d56190	1184
samdanbury	6:37b6d0d56190	1185	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
samdanbury	6:37b6d0d56190	1186	if (pcb == NULL) {
samdanbury	6:37b6d0d56190	1187	/* Try killing oldest connection in TIME-WAIT. */
samdanbury	6:37b6d0d56190	1188	LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing off oldest TIME-WAIT connection\n"));
samdanbury	6:37b6d0d56190	1189	tcp_kill_timewait();
samdanbury	6:37b6d0d56190	1190	/* Try to allocate a tcp_pcb again. */
samdanbury	6:37b6d0d56190	1191	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
samdanbury	6:37b6d0d56190	1192	if (pcb == NULL) {
samdanbury	6:37b6d0d56190	1193	/* Try killing active connections with lower priority than the new one. */
samdanbury	6:37b6d0d56190	1194	LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing connection with prio lower than %d\n", prio));
samdanbury	6:37b6d0d56190	1195	tcp_kill_prio(prio);
samdanbury	6:37b6d0d56190	1196	/* Try to allocate a tcp_pcb again. */
samdanbury	6:37b6d0d56190	1197	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
samdanbury	6:37b6d0d56190	1198	if (pcb != NULL) {
samdanbury	6:37b6d0d56190	1199	/* adjust err stats: memp_malloc failed twice before */
samdanbury	6:37b6d0d56190	1200	MEMP_STATS_DEC(err, MEMP_TCP_PCB);
samdanbury	6:37b6d0d56190	1201	}
samdanbury	6:37b6d0d56190	1202	}
samdanbury	6:37b6d0d56190	1203	if (pcb != NULL) {
samdanbury	6:37b6d0d56190	1204	/* adjust err stats: timewait PCB was freed above */
samdanbury	6:37b6d0d56190	1205	MEMP_STATS_DEC(err, MEMP_TCP_PCB);
samdanbury	6:37b6d0d56190	1206	}
samdanbury	6:37b6d0d56190	1207	}
samdanbury	6:37b6d0d56190	1208	if (pcb != NULL) {
samdanbury	6:37b6d0d56190	1209	memset(pcb, 0, sizeof(struct tcp_pcb));
samdanbury	6:37b6d0d56190	1210	pcb->prio = prio;
samdanbury	6:37b6d0d56190	1211	pcb->snd_buf = TCP_SND_BUF;
samdanbury	6:37b6d0d56190	1212	pcb->snd_queuelen = 0;
samdanbury	6:37b6d0d56190	1213	pcb->rcv_wnd = TCP_WND;
samdanbury	6:37b6d0d56190	1214	pcb->rcv_ann_wnd = TCP_WND;
samdanbury	6:37b6d0d56190	1215	pcb->tos = 0;
samdanbury	6:37b6d0d56190	1216	pcb->ttl = TCP_TTL;
samdanbury	6:37b6d0d56190	1217	/* As initial send MSS, we use TCP_MSS but limit it to 536.
samdanbury	6:37b6d0d56190	1218	The send MSS is updated when an MSS option is received. */
samdanbury	6:37b6d0d56190	1219	pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
samdanbury	6:37b6d0d56190	1220	pcb->rto = 3000 / TCP_SLOW_INTERVAL;
samdanbury	6:37b6d0d56190	1221	pcb->sa = 0;
samdanbury	6:37b6d0d56190	1222	pcb->sv = 3000 / TCP_SLOW_INTERVAL;
samdanbury	6:37b6d0d56190	1223	pcb->rtime = -1;
samdanbury	6:37b6d0d56190	1224	pcb->cwnd = 1;
samdanbury	6:37b6d0d56190	1225	iss = tcp_next_iss();
samdanbury	6:37b6d0d56190	1226	pcb->snd_wl2 = iss;
samdanbury	6:37b6d0d56190	1227	pcb->snd_nxt = iss;
samdanbury	6:37b6d0d56190	1228	pcb->lastack = iss;
samdanbury	6:37b6d0d56190	1229	pcb->snd_lbb = iss;
samdanbury	6:37b6d0d56190	1230	pcb->tmr = tcp_ticks;
samdanbury	6:37b6d0d56190	1231
samdanbury	6:37b6d0d56190	1232	pcb->polltmr = 0;
samdanbury	6:37b6d0d56190	1233
samdanbury	6:37b6d0d56190	1234	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	1235	pcb->recv = tcp_recv_null;
samdanbury	6:37b6d0d56190	1236	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	1237
samdanbury	6:37b6d0d56190	1238	/* Init KEEPALIVE timer */
samdanbury	6:37b6d0d56190	1239	pcb->keep_idle = TCP_KEEPIDLE_DEFAULT;
samdanbury	6:37b6d0d56190	1240
samdanbury	6:37b6d0d56190	1241	#if LWIP_TCP_KEEPALIVE
samdanbury	6:37b6d0d56190	1242	pcb->keep_intvl = TCP_KEEPINTVL_DEFAULT;
samdanbury	6:37b6d0d56190	1243	pcb->keep_cnt = TCP_KEEPCNT_DEFAULT;
samdanbury	6:37b6d0d56190	1244	#endif /* LWIP_TCP_KEEPALIVE */
samdanbury	6:37b6d0d56190	1245
samdanbury	6:37b6d0d56190	1246	pcb->keep_cnt_sent = 0;
samdanbury	6:37b6d0d56190	1247	}
samdanbury	6:37b6d0d56190	1248	return pcb;
samdanbury	6:37b6d0d56190	1249	}
samdanbury	6:37b6d0d56190	1250
samdanbury	6:37b6d0d56190	1251	/**
samdanbury	6:37b6d0d56190	1252	* Creates a new TCP protocol control block but doesn't place it on
samdanbury	6:37b6d0d56190	1253	* any of the TCP PCB lists.
samdanbury	6:37b6d0d56190	1254	* The pcb is not put on any list until binding using tcp_bind().
samdanbury	6:37b6d0d56190	1255	*
samdanbury	6:37b6d0d56190	1256	* @internal: Maybe there should be a idle TCP PCB list where these
samdanbury	6:37b6d0d56190	1257	* PCBs are put on. Port reservation using tcp_bind() is implemented but
samdanbury	6:37b6d0d56190	1258	* allocated pcbs that are not bound can't be killed automatically if wanting
samdanbury	6:37b6d0d56190	1259	* to allocate a pcb with higher prio (@see tcp_kill_prio())
samdanbury	6:37b6d0d56190	1260	*
samdanbury	6:37b6d0d56190	1261	* @return a new tcp_pcb that initially is in state CLOSED
samdanbury	6:37b6d0d56190	1262	*/
samdanbury	6:37b6d0d56190	1263	struct tcp_pcb *
samdanbury	6:37b6d0d56190	1264	tcp_new(void)
samdanbury	6:37b6d0d56190	1265	{
samdanbury	6:37b6d0d56190	1266	return tcp_alloc(TCP_PRIO_NORMAL);
samdanbury	6:37b6d0d56190	1267	}
samdanbury	6:37b6d0d56190	1268
samdanbury	6:37b6d0d56190	1269	/**
samdanbury	6:37b6d0d56190	1270	* Used to specify the argument that should be passed callback
samdanbury	6:37b6d0d56190	1271	* functions.
samdanbury	6:37b6d0d56190	1272	*
samdanbury	6:37b6d0d56190	1273	* @param pcb tcp_pcb to set the callback argument
samdanbury	6:37b6d0d56190	1274	* @param arg void pointer argument to pass to callback functions
samdanbury	6:37b6d0d56190	1275	*/
samdanbury	6:37b6d0d56190	1276	void
samdanbury	6:37b6d0d56190	1277	tcp_arg(struct tcp_pcb pcb, void arg)
samdanbury	6:37b6d0d56190	1278	{
samdanbury	6:37b6d0d56190	1279	pcb->callback_arg = arg;
samdanbury	6:37b6d0d56190	1280	}
samdanbury	6:37b6d0d56190	1281	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	1282
samdanbury	6:37b6d0d56190	1283	/**
samdanbury	6:37b6d0d56190	1284	* Used to specify the function that should be called when a TCP
samdanbury	6:37b6d0d56190	1285	* connection receives data.
samdanbury	6:37b6d0d56190	1286	*
samdanbury	6:37b6d0d56190	1287	* @param pcb tcp_pcb to set the recv callback
samdanbury	6:37b6d0d56190	1288	* @param recv callback function to call for this pcb when data is received
samdanbury	6:37b6d0d56190	1289	*/
samdanbury	6:37b6d0d56190	1290	void
samdanbury	6:37b6d0d56190	1291	tcp_recv(struct tcp_pcb *pcb, tcp_recv_fn recv)
samdanbury	6:37b6d0d56190	1292	{
samdanbury	6:37b6d0d56190	1293	pcb->recv = recv;
samdanbury	6:37b6d0d56190	1294	}
samdanbury	6:37b6d0d56190	1295
samdanbury	6:37b6d0d56190	1296	/**
samdanbury	6:37b6d0d56190	1297	* Used to specify the function that should be called when TCP data
samdanbury	6:37b6d0d56190	1298	* has been successfully delivered to the remote host.
samdanbury	6:37b6d0d56190	1299	*
samdanbury	6:37b6d0d56190	1300	* @param pcb tcp_pcb to set the sent callback
samdanbury	6:37b6d0d56190	1301	* @param sent callback function to call for this pcb when data is successfully sent
samdanbury	6:37b6d0d56190	1302	*/
samdanbury	6:37b6d0d56190	1303	void
samdanbury	6:37b6d0d56190	1304	tcp_sent(struct tcp_pcb *pcb, tcp_sent_fn sent)
samdanbury	6:37b6d0d56190	1305	{
samdanbury	6:37b6d0d56190	1306	pcb->sent = sent;
samdanbury	6:37b6d0d56190	1307	}
samdanbury	6:37b6d0d56190	1308
samdanbury	6:37b6d0d56190	1309	/**
samdanbury	6:37b6d0d56190	1310	* Used to specify the function that should be called when a fatal error
samdanbury	6:37b6d0d56190	1311	* has occured on the connection.
samdanbury	6:37b6d0d56190	1312	*
samdanbury	6:37b6d0d56190	1313	* @param pcb tcp_pcb to set the err callback
samdanbury	6:37b6d0d56190	1314	* @param err callback function to call for this pcb when a fatal error
samdanbury	6:37b6d0d56190	1315	* has occured on the connection
samdanbury	6:37b6d0d56190	1316	*/
samdanbury	6:37b6d0d56190	1317	void
samdanbury	6:37b6d0d56190	1318	tcp_err(struct tcp_pcb *pcb, tcp_err_fn err)
samdanbury	6:37b6d0d56190	1319	{
samdanbury	6:37b6d0d56190	1320	pcb->errf = err;
samdanbury	6:37b6d0d56190	1321	}
samdanbury	6:37b6d0d56190	1322
samdanbury	6:37b6d0d56190	1323	/**
samdanbury	6:37b6d0d56190	1324	* Used for specifying the function that should be called when a
samdanbury	6:37b6d0d56190	1325	* LISTENing connection has been connected to another host.
samdanbury	6:37b6d0d56190	1326	*
samdanbury	6:37b6d0d56190	1327	* @param pcb tcp_pcb to set the accept callback
samdanbury	6:37b6d0d56190	1328	* @param accept callback function to call for this pcb when LISTENing
samdanbury	6:37b6d0d56190	1329	* connection has been connected to another host
samdanbury	6:37b6d0d56190	1330	*/
samdanbury	6:37b6d0d56190	1331	void
samdanbury	6:37b6d0d56190	1332	tcp_accept(struct tcp_pcb *pcb, tcp_accept_fn accept)
samdanbury	6:37b6d0d56190	1333	{
samdanbury	6:37b6d0d56190	1334	pcb->accept = accept;
samdanbury	6:37b6d0d56190	1335	}
samdanbury	6:37b6d0d56190	1336	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	1337
samdanbury	6:37b6d0d56190	1338
samdanbury	6:37b6d0d56190	1339	/**
samdanbury	6:37b6d0d56190	1340	* Used to specify the function that should be called periodically
samdanbury	6:37b6d0d56190	1341	* from TCP. The interval is specified in terms of the TCP coarse
samdanbury	6:37b6d0d56190	1342	* timer interval, which is called twice a second.
samdanbury	6:37b6d0d56190	1343	*
samdanbury	6:37b6d0d56190	1344	*/
samdanbury	6:37b6d0d56190	1345	void
samdanbury	6:37b6d0d56190	1346	tcp_poll(struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval)
samdanbury	6:37b6d0d56190	1347	{
samdanbury	6:37b6d0d56190	1348	#if LWIP_CALLBACK_API
samdanbury	6:37b6d0d56190	1349	pcb->poll = poll;
samdanbury	6:37b6d0d56190	1350	#else /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	1351	LWIP_UNUSED_ARG(poll);
samdanbury	6:37b6d0d56190	1352	#endif /* LWIP_CALLBACK_API */
samdanbury	6:37b6d0d56190	1353	pcb->pollinterval = interval;
samdanbury	6:37b6d0d56190	1354	}
samdanbury	6:37b6d0d56190	1355
samdanbury	6:37b6d0d56190	1356	/**
samdanbury	6:37b6d0d56190	1357	* Purges a TCP PCB. Removes any buffered data and frees the buffer memory
samdanbury	6:37b6d0d56190	1358	* (pcb->ooseq, pcb->unsent and pcb->unacked are freed).
samdanbury	6:37b6d0d56190	1359	*
samdanbury	6:37b6d0d56190	1360	* @param pcb tcp_pcb to purge. The pcb itself is not deallocated!
samdanbury	6:37b6d0d56190	1361	*/
samdanbury	6:37b6d0d56190	1362	void
samdanbury	6:37b6d0d56190	1363	tcp_pcb_purge(struct tcp_pcb *pcb)
samdanbury	6:37b6d0d56190	1364	{
samdanbury	6:37b6d0d56190	1365	if (pcb->state != CLOSED &&
samdanbury	6:37b6d0d56190	1366	pcb->state != TIME_WAIT &&
samdanbury	6:37b6d0d56190	1367	pcb->state != LISTEN) {
samdanbury	6:37b6d0d56190	1368
samdanbury	6:37b6d0d56190	1369	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge\n"));
samdanbury	6:37b6d0d56190	1370
samdanbury	6:37b6d0d56190	1371	#if TCP_LISTEN_BACKLOG
samdanbury	6:37b6d0d56190	1372	if (pcb->state == SYN_RCVD) {
samdanbury	6:37b6d0d56190	1373	/* Need to find the corresponding listen_pcb and decrease its accepts_pending */
samdanbury	6:37b6d0d56190	1374	struct tcp_pcb_listen *lpcb;
samdanbury	6:37b6d0d56190	1375	LWIP_ASSERT("tcp_pcb_purge: pcb->state == SYN_RCVD but tcp_listen_pcbs is NULL",
samdanbury	6:37b6d0d56190	1376	tcp_listen_pcbs.listen_pcbs != NULL);
samdanbury	6:37b6d0d56190	1377	for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
samdanbury	6:37b6d0d56190	1378	if ((lpcb->local_port == pcb->local_port) &&
samdanbury	6:37b6d0d56190	1379	(ip_addr_isany(&lpcb->local_ip) \|\|
samdanbury	6:37b6d0d56190	1380	ip_addr_cmp(&pcb->local_ip, &lpcb->local_ip))) {
samdanbury	6:37b6d0d56190	1381	/* port and address of the listen pcb match the timed-out pcb */
samdanbury	6:37b6d0d56190	1382	LWIP_ASSERT("tcp_pcb_purge: listen pcb does not have accepts pending",
samdanbury	6:37b6d0d56190	1383	lpcb->accepts_pending > 0);
samdanbury	6:37b6d0d56190	1384	lpcb->accepts_pending--;
samdanbury	6:37b6d0d56190	1385	break;
samdanbury	6:37b6d0d56190	1386	}
samdanbury	6:37b6d0d56190	1387	}
samdanbury	6:37b6d0d56190	1388	}
samdanbury	6:37b6d0d56190	1389	#endif /* TCP_LISTEN_BACKLOG */
samdanbury	6:37b6d0d56190	1390
samdanbury	6:37b6d0d56190	1391
samdanbury	6:37b6d0d56190	1392	if (pcb->refused_data != NULL) {
samdanbury	6:37b6d0d56190	1393	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->refused_data\n"));
samdanbury	6:37b6d0d56190	1394	pbuf_free(pcb->refused_data);
samdanbury	6:37b6d0d56190	1395	pcb->refused_data = NULL;
samdanbury	6:37b6d0d56190	1396	}
samdanbury	6:37b6d0d56190	1397	if (pcb->unsent != NULL) {
samdanbury	6:37b6d0d56190	1398	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: not all data sent\n"));
samdanbury	6:37b6d0d56190	1399	}
samdanbury	6:37b6d0d56190	1400	if (pcb->unacked != NULL) {
samdanbury	6:37b6d0d56190	1401	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->unacked\n"));
samdanbury	6:37b6d0d56190	1402	}
samdanbury	6:37b6d0d56190	1403	#if TCP_QUEUE_OOSEQ
samdanbury	6:37b6d0d56190	1404	if (pcb->ooseq != NULL) {
samdanbury	6:37b6d0d56190	1405	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->ooseq\n"));
samdanbury	6:37b6d0d56190	1406	}
samdanbury	6:37b6d0d56190	1407	tcp_segs_free(pcb->ooseq);
samdanbury	6:37b6d0d56190	1408	pcb->ooseq = NULL;
samdanbury	6:37b6d0d56190	1409	#endif /* TCP_QUEUE_OOSEQ */
samdanbury	6:37b6d0d56190	1410
samdanbury	6:37b6d0d56190	1411	/* Stop the retransmission timer as it will expect data on unacked
samdanbury	6:37b6d0d56190	1412	queue if it fires */
samdanbury	6:37b6d0d56190	1413	pcb->rtime = -1;
samdanbury	6:37b6d0d56190	1414
samdanbury	6:37b6d0d56190	1415	tcp_segs_free(pcb->unsent);
samdanbury	6:37b6d0d56190	1416	tcp_segs_free(pcb->unacked);
samdanbury	6:37b6d0d56190	1417	pcb->unacked = pcb->unsent = NULL;
samdanbury	6:37b6d0d56190	1418	#if TCP_OVERSIZE
samdanbury	6:37b6d0d56190	1419	pcb->unsent_oversize = 0;
samdanbury	6:37b6d0d56190	1420	#endif /* TCP_OVERSIZE */
samdanbury	6:37b6d0d56190	1421	}
samdanbury	6:37b6d0d56190	1422	}
samdanbury	6:37b6d0d56190	1423
samdanbury	6:37b6d0d56190	1424	/**
samdanbury	6:37b6d0d56190	1425	* Purges the PCB and removes it from a PCB list. Any delayed ACKs are sent first.
samdanbury	6:37b6d0d56190	1426	*
samdanbury	6:37b6d0d56190	1427	* @param pcblist PCB list to purge.
samdanbury	6:37b6d0d56190	1428	* @param pcb tcp_pcb to purge. The pcb itself is NOT deallocated!
samdanbury	6:37b6d0d56190	1429	*/
samdanbury	6:37b6d0d56190	1430	void
samdanbury	6:37b6d0d56190	1431	tcp_pcb_remove(struct tcp_pcb *pcblist, struct tcp_pcb pcb)
samdanbury	6:37b6d0d56190	1432	{
samdanbury	6:37b6d0d56190	1433	TCP_RMV(pcblist, pcb);
samdanbury	6:37b6d0d56190	1434
samdanbury	6:37b6d0d56190	1435	tcp_pcb_purge(pcb);
samdanbury	6:37b6d0d56190	1436
samdanbury	6:37b6d0d56190	1437	/* if there is an outstanding delayed ACKs, send it */
samdanbury	6:37b6d0d56190	1438	if (pcb->state != TIME_WAIT &&
samdanbury	6:37b6d0d56190	1439	pcb->state != LISTEN &&
samdanbury	6:37b6d0d56190	1440	pcb->flags & TF_ACK_DELAY) {
samdanbury	6:37b6d0d56190	1441	pcb->flags \|= TF_ACK_NOW;
samdanbury	6:37b6d0d56190	1442	tcp_output(pcb);
samdanbury	6:37b6d0d56190	1443	}
samdanbury	6:37b6d0d56190	1444
samdanbury	6:37b6d0d56190	1445	if (pcb->state != LISTEN) {
samdanbury	6:37b6d0d56190	1446	LWIP_ASSERT("unsent segments leaking", pcb->unsent == NULL);
samdanbury	6:37b6d0d56190	1447	LWIP_ASSERT("unacked segments leaking", pcb->unacked == NULL);
samdanbury	6:37b6d0d56190	1448	#if TCP_QUEUE_OOSEQ
samdanbury	6:37b6d0d56190	1449	LWIP_ASSERT("ooseq segments leaking", pcb->ooseq == NULL);
samdanbury	6:37b6d0d56190	1450	#endif /* TCP_QUEUE_OOSEQ */
samdanbury	6:37b6d0d56190	1451	}
samdanbury	6:37b6d0d56190	1452
samdanbury	6:37b6d0d56190	1453	pcb->state = CLOSED;
samdanbury	6:37b6d0d56190	1454
samdanbury	6:37b6d0d56190	1455	LWIP_ASSERT("tcp_pcb_remove: tcp_pcbs_sane()", tcp_pcbs_sane());
samdanbury	6:37b6d0d56190	1456	}
samdanbury	6:37b6d0d56190	1457
samdanbury	6:37b6d0d56190	1458	/**
samdanbury	6:37b6d0d56190	1459	* Calculates a new initial sequence number for new connections.
samdanbury	6:37b6d0d56190	1460	*
samdanbury	6:37b6d0d56190	1461	* @return u32_t pseudo random sequence number
samdanbury	6:37b6d0d56190	1462	*/
samdanbury	6:37b6d0d56190	1463	u32_t
samdanbury	6:37b6d0d56190	1464	tcp_next_iss(void)
samdanbury	6:37b6d0d56190	1465	{
samdanbury	6:37b6d0d56190	1466	static u32_t iss = 6510;
samdanbury	6:37b6d0d56190	1467
samdanbury	6:37b6d0d56190	1468	iss += tcp_ticks; /* XXX */
samdanbury	6:37b6d0d56190	1469	return iss;
samdanbury	6:37b6d0d56190	1470	}
samdanbury	6:37b6d0d56190	1471
samdanbury	6:37b6d0d56190	1472	#if TCP_CALCULATE_EFF_SEND_MSS
samdanbury	6:37b6d0d56190	1473	/**
samdanbury	6:37b6d0d56190	1474	* Calcluates the effective send mss that can be used for a specific IP address
samdanbury	6:37b6d0d56190	1475	* by using ip_route to determin the netif used to send to the address and
samdanbury	6:37b6d0d56190	1476	* calculating the minimum of TCP_MSS and that netif's mtu (if set).
samdanbury	6:37b6d0d56190	1477	*/
samdanbury	6:37b6d0d56190	1478	u16_t
samdanbury	6:37b6d0d56190	1479	tcp_eff_send_mss(u16_t sendmss, ip_addr_t *addr)
samdanbury	6:37b6d0d56190	1480	{
samdanbury	6:37b6d0d56190	1481	u16_t mss_s;
samdanbury	6:37b6d0d56190	1482	struct netif *outif;
samdanbury	6:37b6d0d56190	1483
samdanbury	6:37b6d0d56190	1484	outif = ip_route(addr);
samdanbury	6:37b6d0d56190	1485	if ((outif != NULL) && (outif->mtu != 0)) {
samdanbury	6:37b6d0d56190	1486	mss_s = outif->mtu - IP_HLEN - TCP_HLEN;
samdanbury	6:37b6d0d56190	1487	/* RFC 1122, chap 4.2.2.6:
samdanbury	6:37b6d0d56190	1488	* Eff.snd.MSS = min(SendMSS+20, MMS_S) - TCPhdrsize - IPoptionsize
samdanbury	6:37b6d0d56190	1489	* We correct for TCP options in tcp_write(), and don't support IP options.
samdanbury	6:37b6d0d56190	1490	*/
samdanbury	6:37b6d0d56190	1491	sendmss = LWIP_MIN(sendmss, mss_s);
samdanbury	6:37b6d0d56190	1492	}
samdanbury	6:37b6d0d56190	1493	return sendmss;
samdanbury	6:37b6d0d56190	1494	}
samdanbury	6:37b6d0d56190	1495	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
samdanbury	6:37b6d0d56190	1496
samdanbury	6:37b6d0d56190	1497	const char*
samdanbury	6:37b6d0d56190	1498	tcp_debug_state_str(enum tcp_state s)
samdanbury	6:37b6d0d56190	1499	{
samdanbury	6:37b6d0d56190	1500	return tcp_state_str[s];
samdanbury	6:37b6d0d56190	1501	}
samdanbury	6:37b6d0d56190	1502
samdanbury	6:37b6d0d56190	1503	#if TCP_DEBUG \|\| TCP_INPUT_DEBUG \|\| TCP_OUTPUT_DEBUG
samdanbury	6:37b6d0d56190	1504	/**
samdanbury	6:37b6d0d56190	1505	* Print a tcp header for debugging purposes.
samdanbury	6:37b6d0d56190	1506	*
samdanbury	6:37b6d0d56190	1507	* @param tcphdr pointer to a struct tcp_hdr
samdanbury	6:37b6d0d56190	1508	*/
samdanbury	6:37b6d0d56190	1509	void
samdanbury	6:37b6d0d56190	1510	tcp_debug_print(struct tcp_hdr *tcphdr)
samdanbury	6:37b6d0d56190	1511	{
samdanbury	6:37b6d0d56190	1512	LWIP_DEBUGF(TCP_DEBUG, ("TCP header:\n"));
samdanbury	6:37b6d0d56190	1513	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
samdanbury	6:37b6d0d56190	1514	LWIP_DEBUGF(TCP_DEBUG, ("\| %5"U16_F" \| %5"U16_F" \| (src port, dest port)\n",
samdanbury	6:37b6d0d56190	1515	ntohs(tcphdr->src), ntohs(tcphdr->dest)));
samdanbury	6:37b6d0d56190	1516	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
samdanbury	6:37b6d0d56190	1517	LWIP_DEBUGF(TCP_DEBUG, ("\| %010"U32_F" \| (seq no)\n",
samdanbury	6:37b6d0d56190	1518	ntohl(tcphdr->seqno)));
samdanbury	6:37b6d0d56190	1519	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
samdanbury	6:37b6d0d56190	1520	LWIP_DEBUGF(TCP_DEBUG, ("\| %010"U32_F" \| (ack no)\n",
samdanbury	6:37b6d0d56190	1521	ntohl(tcphdr->ackno)));
samdanbury	6:37b6d0d56190	1522	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
samdanbury	6:37b6d0d56190	1523	LWIP_DEBUGF(TCP_DEBUG, ("\| %2"U16_F" \| \|%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"\| %5"U16_F" \| (hdrlen, flags (",
samdanbury	6:37b6d0d56190	1524	TCPH_HDRLEN(tcphdr),
samdanbury	6:37b6d0d56190	1525	TCPH_FLAGS(tcphdr) >> 5 & 1,
samdanbury	6:37b6d0d56190	1526	TCPH_FLAGS(tcphdr) >> 4 & 1,
samdanbury	6:37b6d0d56190	1527	TCPH_FLAGS(tcphdr) >> 3 & 1,
samdanbury	6:37b6d0d56190	1528	TCPH_FLAGS(tcphdr) >> 2 & 1,
samdanbury	6:37b6d0d56190	1529	TCPH_FLAGS(tcphdr) >> 1 & 1,
samdanbury	6:37b6d0d56190	1530	TCPH_FLAGS(tcphdr) & 1,
samdanbury	6:37b6d0d56190	1531	ntohs(tcphdr->wnd)));
samdanbury	6:37b6d0d56190	1532	tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
samdanbury	6:37b6d0d56190	1533	LWIP_DEBUGF(TCP_DEBUG, ("), win)\n"));
samdanbury	6:37b6d0d56190	1534	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
samdanbury	6:37b6d0d56190	1535	LWIP_DEBUGF(TCP_DEBUG, ("\| 0x%04"X16_F" \| %5"U16_F" \| (chksum, urgp)\n",
samdanbury	6:37b6d0d56190	1536	ntohs(tcphdr->chksum), ntohs(tcphdr->urgp)));
samdanbury	6:37b6d0d56190	1537	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
samdanbury	6:37b6d0d56190	1538	}
samdanbury	6:37b6d0d56190	1539
samdanbury	6:37b6d0d56190	1540	/**
samdanbury	6:37b6d0d56190	1541	* Print a tcp state for debugging purposes.
samdanbury	6:37b6d0d56190	1542	*
samdanbury	6:37b6d0d56190	1543	* @param s enum tcp_state to print
samdanbury	6:37b6d0d56190	1544	*/
samdanbury	6:37b6d0d56190	1545	void
samdanbury	6:37b6d0d56190	1546	tcp_debug_print_state(enum tcp_state s)
samdanbury	6:37b6d0d56190	1547	{
samdanbury	6:37b6d0d56190	1548	LWIP_DEBUGF(TCP_DEBUG, ("State: %s\n", tcp_state_str[s]));
samdanbury	6:37b6d0d56190	1549	}
samdanbury	6:37b6d0d56190	1550
samdanbury	6:37b6d0d56190	1551	/**
samdanbury	6:37b6d0d56190	1552	* Print tcp flags for debugging purposes.
samdanbury	6:37b6d0d56190	1553	*
samdanbury	6:37b6d0d56190	1554	* @param flags tcp flags, all active flags are printed
samdanbury	6:37b6d0d56190	1555	*/
samdanbury	6:37b6d0d56190	1556	void
samdanbury	6:37b6d0d56190	1557	tcp_debug_print_flags(u8_t flags)
samdanbury	6:37b6d0d56190	1558	{
samdanbury	6:37b6d0d56190	1559	if (flags & TCP_FIN) {
samdanbury	6:37b6d0d56190	1560	LWIP_DEBUGF(TCP_DEBUG, ("FIN "));
samdanbury	6:37b6d0d56190	1561	}
samdanbury	6:37b6d0d56190	1562	if (flags & TCP_SYN) {
samdanbury	6:37b6d0d56190	1563	LWIP_DEBUGF(TCP_DEBUG, ("SYN "));
samdanbury	6:37b6d0d56190	1564	}
samdanbury	6:37b6d0d56190	1565	if (flags & TCP_RST) {
samdanbury	6:37b6d0d56190	1566	LWIP_DEBUGF(TCP_DEBUG, ("RST "));
samdanbury	6:37b6d0d56190	1567	}
samdanbury	6:37b6d0d56190	1568	if (flags & TCP_PSH) {
samdanbury	6:37b6d0d56190	1569	LWIP_DEBUGF(TCP_DEBUG, ("PSH "));
samdanbury	6:37b6d0d56190	1570	}
samdanbury	6:37b6d0d56190	1571	if (flags & TCP_ACK) {
samdanbury	6:37b6d0d56190	1572	LWIP_DEBUGF(TCP_DEBUG, ("ACK "));
samdanbury	6:37b6d0d56190	1573	}
samdanbury	6:37b6d0d56190	1574	if (flags & TCP_URG) {
samdanbury	6:37b6d0d56190	1575	LWIP_DEBUGF(TCP_DEBUG, ("URG "));
samdanbury	6:37b6d0d56190	1576	}
samdanbury	6:37b6d0d56190	1577	if (flags & TCP_ECE) {
samdanbury	6:37b6d0d56190	1578	LWIP_DEBUGF(TCP_DEBUG, ("ECE "));
samdanbury	6:37b6d0d56190	1579	}
samdanbury	6:37b6d0d56190	1580	if (flags & TCP_CWR) {
samdanbury	6:37b6d0d56190	1581	LWIP_DEBUGF(TCP_DEBUG, ("CWR "));
samdanbury	6:37b6d0d56190	1582	}
samdanbury	6:37b6d0d56190	1583	LWIP_DEBUGF(TCP_DEBUG, ("\n"));
samdanbury	6:37b6d0d56190	1584	}
samdanbury	6:37b6d0d56190	1585
samdanbury	6:37b6d0d56190	1586	/**
samdanbury	6:37b6d0d56190	1587	* Print all tcp_pcbs in every list for debugging purposes.
samdanbury	6:37b6d0d56190	1588	*/
samdanbury	6:37b6d0d56190	1589	void
samdanbury	6:37b6d0d56190	1590	tcp_debug_print_pcbs(void)
samdanbury	6:37b6d0d56190	1591	{
samdanbury	6:37b6d0d56190	1592	struct tcp_pcb *pcb;
samdanbury	6:37b6d0d56190	1593	LWIP_DEBUGF(TCP_DEBUG, ("Active PCB states:\n"));
samdanbury	6:37b6d0d56190	1594	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1595	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
samdanbury	6:37b6d0d56190	1596	pcb->local_port, pcb->remote_port,
samdanbury	6:37b6d0d56190	1597	pcb->snd_nxt, pcb->rcv_nxt));
samdanbury	6:37b6d0d56190	1598	tcp_debug_print_state(pcb->state);
samdanbury	6:37b6d0d56190	1599	}
samdanbury	6:37b6d0d56190	1600	LWIP_DEBUGF(TCP_DEBUG, ("Listen PCB states:\n"));
samdanbury	6:37b6d0d56190	1601	for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1602	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
samdanbury	6:37b6d0d56190	1603	pcb->local_port, pcb->remote_port,
samdanbury	6:37b6d0d56190	1604	pcb->snd_nxt, pcb->rcv_nxt));
samdanbury	6:37b6d0d56190	1605	tcp_debug_print_state(pcb->state);
samdanbury	6:37b6d0d56190	1606	}
samdanbury	6:37b6d0d56190	1607	LWIP_DEBUGF(TCP_DEBUG, ("TIME-WAIT PCB states:\n"));
samdanbury	6:37b6d0d56190	1608	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1609	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
samdanbury	6:37b6d0d56190	1610	pcb->local_port, pcb->remote_port,
samdanbury	6:37b6d0d56190	1611	pcb->snd_nxt, pcb->rcv_nxt));
samdanbury	6:37b6d0d56190	1612	tcp_debug_print_state(pcb->state);
samdanbury	6:37b6d0d56190	1613	}
samdanbury	6:37b6d0d56190	1614	}
samdanbury	6:37b6d0d56190	1615
samdanbury	6:37b6d0d56190	1616	/**
samdanbury	6:37b6d0d56190	1617	* Check state consistency of the tcp_pcb lists.
samdanbury	6:37b6d0d56190	1618	*/
samdanbury	6:37b6d0d56190	1619	s16_t
samdanbury	6:37b6d0d56190	1620	tcp_pcbs_sane(void)
samdanbury	6:37b6d0d56190	1621	{
samdanbury	6:37b6d0d56190	1622	struct tcp_pcb *pcb;
samdanbury	6:37b6d0d56190	1623	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1624	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != CLOSED", pcb->state != CLOSED);
samdanbury	6:37b6d0d56190	1625	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != LISTEN", pcb->state != LISTEN);
samdanbury	6:37b6d0d56190	1626	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
samdanbury	6:37b6d0d56190	1627	}
samdanbury	6:37b6d0d56190	1628	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
samdanbury	6:37b6d0d56190	1629	LWIP_ASSERT("tcp_pcbs_sane: tw pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
samdanbury	6:37b6d0d56190	1630	}
samdanbury	6:37b6d0d56190	1631	return 1;
samdanbury	6:37b6d0d56190	1632	}
samdanbury	6:37b6d0d56190	1633	#endif /* TCP_DEBUG */
samdanbury	6:37b6d0d56190	1634
samdanbury	6:37b6d0d56190	1635	#endif /* LWIP_TCP */

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	12 Mar 2015
Imports:	43
Forks:	1
Commits:	12
Dependents:	0
Dependencies:	7
Followers:	86

EthernetInterface/lwip/core/tcp.c@6:37b6d0d56190, 2014-08-20 (annotated)

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