NetServicesMinHTTPMod - Copy of NetServicesMin with the HTTP Client libra…

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Copy of NetServicesMin with the HTTP Client library. Includes modification for HTTP servers which send the HTTP status line in its own packet.

lwip/core/tcp.c@0:18dd877d2c77, 2011-05-26 (annotated)

Committer:: andrewbonney
Date:: Thu May 26 10:02:40 2011 +0000
Revision:: 0:18dd877d2c77

Who changed what in which revision?

User	Revision	Line number	New contents of line
andrewbonney	0:18dd877d2c77	1	/**
andrewbonney	0:18dd877d2c77	2	* @file
andrewbonney	0:18dd877d2c77	3	* Transmission Control Protocol for IP
andrewbonney	0:18dd877d2c77	4	*
andrewbonney	0:18dd877d2c77	5	* This file contains common functions for the TCP implementation, such as functinos
andrewbonney	0:18dd877d2c77	6	* for manipulating the data structures and the TCP timer functions. TCP functions
andrewbonney	0:18dd877d2c77	7	* related to input and output is found in tcp_in.c and tcp_out.c respectively.
andrewbonney	0:18dd877d2c77	8	*
andrewbonney	0:18dd877d2c77	9	*/
andrewbonney	0:18dd877d2c77	10
andrewbonney	0:18dd877d2c77	11	/*
andrewbonney	0:18dd877d2c77	12	* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
andrewbonney	0:18dd877d2c77	13	* All rights reserved.
andrewbonney	0:18dd877d2c77	14	*
andrewbonney	0:18dd877d2c77	15	* Redistribution and use in source and binary forms, with or without modification,
andrewbonney	0:18dd877d2c77	16	* are permitted provided that the following conditions are met:
andrewbonney	0:18dd877d2c77	17	*
andrewbonney	0:18dd877d2c77	18	* 1. Redistributions of source code must retain the above copyright notice,
andrewbonney	0:18dd877d2c77	19	* this list of conditions and the following disclaimer.
andrewbonney	0:18dd877d2c77	20	* 2. Redistributions in binary form must reproduce the above copyright notice,
andrewbonney	0:18dd877d2c77	21	* this list of conditions and the following disclaimer in the documentation
andrewbonney	0:18dd877d2c77	22	* and/or other materials provided with the distribution.
andrewbonney	0:18dd877d2c77	23	* 3. The name of the author may not be used to endorse or promote products
andrewbonney	0:18dd877d2c77	24	* derived from this software without specific prior written permission.
andrewbonney	0:18dd877d2c77	25	*
andrewbonney	0:18dd877d2c77	26	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
andrewbonney	0:18dd877d2c77	27	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
andrewbonney	0:18dd877d2c77	28	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
andrewbonney	0:18dd877d2c77	29	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
andrewbonney	0:18dd877d2c77	30	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
andrewbonney	0:18dd877d2c77	31	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
andrewbonney	0:18dd877d2c77	32	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
andrewbonney	0:18dd877d2c77	33	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
andrewbonney	0:18dd877d2c77	34	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
andrewbonney	0:18dd877d2c77	35	* OF SUCH DAMAGE.
andrewbonney	0:18dd877d2c77	36	*
andrewbonney	0:18dd877d2c77	37	* This file is part of the lwIP TCP/IP stack.
andrewbonney	0:18dd877d2c77	38	*
andrewbonney	0:18dd877d2c77	39	* Author: Adam Dunkels <adam@sics.se>
andrewbonney	0:18dd877d2c77	40	*
andrewbonney	0:18dd877d2c77	41	*/
andrewbonney	0:18dd877d2c77	42
andrewbonney	0:18dd877d2c77	43	#include "lwip/opt.h"
andrewbonney	0:18dd877d2c77	44
andrewbonney	0:18dd877d2c77	45	#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
andrewbonney	0:18dd877d2c77	46
andrewbonney	0:18dd877d2c77	47	#include "lwip/def.h"
andrewbonney	0:18dd877d2c77	48	#include "lwip/mem.h"
andrewbonney	0:18dd877d2c77	49	#include "lwip/memp.h"
andrewbonney	0:18dd877d2c77	50	#include "lwip/snmp.h"
andrewbonney	0:18dd877d2c77	51	#include "lwip/tcp.h"
andrewbonney	0:18dd877d2c77	52	#include "lwip/tcp_impl.h"
andrewbonney	0:18dd877d2c77	53	#include "lwip/debug.h"
andrewbonney	0:18dd877d2c77	54	#include "lwip/stats.h"
andrewbonney	0:18dd877d2c77	55
andrewbonney	0:18dd877d2c77	56	#include <string.h>
andrewbonney	0:18dd877d2c77	57
andrewbonney	0:18dd877d2c77	58	const char * const tcp_state_str[] = {
andrewbonney	0:18dd877d2c77	59	"CLOSED",
andrewbonney	0:18dd877d2c77	60	"LISTEN",
andrewbonney	0:18dd877d2c77	61	"SYN_SENT",
andrewbonney	0:18dd877d2c77	62	"SYN_RCVD",
andrewbonney	0:18dd877d2c77	63	"ESTABLISHED",
andrewbonney	0:18dd877d2c77	64	"FIN_WAIT_1",
andrewbonney	0:18dd877d2c77	65	"FIN_WAIT_2",
andrewbonney	0:18dd877d2c77	66	"CLOSE_WAIT",
andrewbonney	0:18dd877d2c77	67	"CLOSING",
andrewbonney	0:18dd877d2c77	68	"LAST_ACK",
andrewbonney	0:18dd877d2c77	69	"TIME_WAIT"
andrewbonney	0:18dd877d2c77	70	};
andrewbonney	0:18dd877d2c77	71
andrewbonney	0:18dd877d2c77	72	/* Incremented every coarse grained timer shot (typically every 500 ms). */
andrewbonney	0:18dd877d2c77	73	u32_t tcp_ticks;
andrewbonney	0:18dd877d2c77	74	const u8_t tcp_backoff[13] =
andrewbonney	0:18dd877d2c77	75	{ 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7};
andrewbonney	0:18dd877d2c77	76	/* Times per slowtmr hits */
andrewbonney	0:18dd877d2c77	77	const u8_t tcp_persist_backoff[7] = { 3, 6, 12, 24, 48, 96, 120 };
andrewbonney	0:18dd877d2c77	78
andrewbonney	0:18dd877d2c77	79	/* The TCP PCB lists. */
andrewbonney	0:18dd877d2c77	80
andrewbonney	0:18dd877d2c77	81	/** List of all TCP PCBs bound but not yet (connected \|\| listening) */
andrewbonney	0:18dd877d2c77	82	struct tcp_pcb *tcp_bound_pcbs;
andrewbonney	0:18dd877d2c77	83	/** List of all TCP PCBs in LISTEN state */
andrewbonney	0:18dd877d2c77	84	union tcp_listen_pcbs_t tcp_listen_pcbs;
andrewbonney	0:18dd877d2c77	85	/** List of all TCP PCBs that are in a state in which
andrewbonney	0:18dd877d2c77	86	* they accept or send data. */
andrewbonney	0:18dd877d2c77	87	struct tcp_pcb *tcp_active_pcbs;
andrewbonney	0:18dd877d2c77	88	/** List of all TCP PCBs in TIME-WAIT state */
andrewbonney	0:18dd877d2c77	89	struct tcp_pcb *tcp_tw_pcbs;
andrewbonney	0:18dd877d2c77	90
andrewbonney	0:18dd877d2c77	91	#define NUM_TCP_PCB_LISTS 4
andrewbonney	0:18dd877d2c77	92	#define NUM_TCP_PCB_LISTS_NO_TIME_WAIT 3
andrewbonney	0:18dd877d2c77	93	/** An array with all (non-temporary) PCB lists, mainly used for smaller code size */
andrewbonney	0:18dd877d2c77	94	struct tcp_pcb **tcp_pcb_lists[] = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
andrewbonney	0:18dd877d2c77	95	&tcp_active_pcbs, &tcp_tw_pcbs};
andrewbonney	0:18dd877d2c77	96
andrewbonney	0:18dd877d2c77	97	/** Only used for temporary storage. */
andrewbonney	0:18dd877d2c77	98	struct tcp_pcb *tcp_tmp_pcb;
andrewbonney	0:18dd877d2c77	99
andrewbonney	0:18dd877d2c77	100	/** Timer counter to handle calling slow-timer from tcp_tmr() */
andrewbonney	0:18dd877d2c77	101	static u8_t tcp_timer;
andrewbonney	0:18dd877d2c77	102	static u16_t tcp_new_port(void);
andrewbonney	0:18dd877d2c77	103
andrewbonney	0:18dd877d2c77	104	/**
andrewbonney	0:18dd877d2c77	105	* Called periodically to dispatch TCP timers.
andrewbonney	0:18dd877d2c77	106	*
andrewbonney	0:18dd877d2c77	107	*/
andrewbonney	0:18dd877d2c77	108	void
andrewbonney	0:18dd877d2c77	109	tcp_tmr(void)
andrewbonney	0:18dd877d2c77	110	{
andrewbonney	0:18dd877d2c77	111	/* Call tcp_fasttmr() every 250 ms */
andrewbonney	0:18dd877d2c77	112	tcp_fasttmr();
andrewbonney	0:18dd877d2c77	113
andrewbonney	0:18dd877d2c77	114	if (++tcp_timer & 1) {
andrewbonney	0:18dd877d2c77	115	/* Call tcp_tmr() every 500 ms, i.e., every other timer
andrewbonney	0:18dd877d2c77	116	tcp_tmr() is called. */
andrewbonney	0:18dd877d2c77	117	tcp_slowtmr();
andrewbonney	0:18dd877d2c77	118	}
andrewbonney	0:18dd877d2c77	119	}
andrewbonney	0:18dd877d2c77	120
andrewbonney	0:18dd877d2c77	121	/**
andrewbonney	0:18dd877d2c77	122	* Closes the TX side of a connection held by the PCB.
andrewbonney	0:18dd877d2c77	123	* For tcp_close(), a RST is sent if the application didn't receive all data
andrewbonney	0:18dd877d2c77	124	* (tcp_recved() not called for all data passed to recv callback).
andrewbonney	0:18dd877d2c77	125	*
andrewbonney	0:18dd877d2c77	126	* Listening pcbs are freed and may not be referenced any more.
andrewbonney	0:18dd877d2c77	127	* Connection pcbs are freed if not yet connected and may not be referenced
andrewbonney	0:18dd877d2c77	128	* any more. If a connection is established (at least SYN received or in
andrewbonney	0:18dd877d2c77	129	* a closing state), the connection is closed, and put in a closing state.
andrewbonney	0:18dd877d2c77	130	* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
andrewbonney	0:18dd877d2c77	131	* unsafe to reference it.
andrewbonney	0:18dd877d2c77	132	*
andrewbonney	0:18dd877d2c77	133	* @param pcb the tcp_pcb to close
andrewbonney	0:18dd877d2c77	134	* @return ERR_OK if connection has been closed
andrewbonney	0:18dd877d2c77	135	* another err_t if closing failed and pcb is not freed
andrewbonney	0:18dd877d2c77	136	*/
andrewbonney	0:18dd877d2c77	137	static err_t
andrewbonney	0:18dd877d2c77	138	tcp_close_shutdown(struct tcp_pcb *pcb, u8_t rst_on_unacked_data)
andrewbonney	0:18dd877d2c77	139	{
andrewbonney	0:18dd877d2c77	140	err_t err;
andrewbonney	0:18dd877d2c77	141
andrewbonney	0:18dd877d2c77	142	if (rst_on_unacked_data && (pcb->state != LISTEN)) {
andrewbonney	0:18dd877d2c77	143	if ((pcb->refused_data != NULL) \|\| (pcb->rcv_wnd != TCP_WND)) {
andrewbonney	0:18dd877d2c77	144	/* Not all data received by application, send RST to tell the remote
andrewbonney	0:18dd877d2c77	145	side about this. */
andrewbonney	0:18dd877d2c77	146	LWIP_ASSERT("pcb->flags & TF_RXCLOSED", pcb->flags & TF_RXCLOSED);
andrewbonney	0:18dd877d2c77	147
andrewbonney	0:18dd877d2c77	148	/* don't call tcp_abort here: we must not deallocate the pcb since
andrewbonney	0:18dd877d2c77	149	that might not be expected when calling tcp_close */
andrewbonney	0:18dd877d2c77	150	tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
andrewbonney	0:18dd877d2c77	151	pcb->local_port, pcb->remote_port);
andrewbonney	0:18dd877d2c77	152
andrewbonney	0:18dd877d2c77	153	tcp_pcb_purge(pcb);
andrewbonney	0:18dd877d2c77	154
andrewbonney	0:18dd877d2c77	155	/* TODO: to which state do we move now? */
andrewbonney	0:18dd877d2c77	156
andrewbonney	0:18dd877d2c77	157	/* move to TIME_WAIT since we close actively */
andrewbonney	0:18dd877d2c77	158	TCP_RMV(&tcp_active_pcbs, pcb);
andrewbonney	0:18dd877d2c77	159	pcb->state = TIME_WAIT;
andrewbonney	0:18dd877d2c77	160	TCP_REG(&tcp_tw_pcbs, pcb);
andrewbonney	0:18dd877d2c77	161
andrewbonney	0:18dd877d2c77	162	return ERR_OK;
andrewbonney	0:18dd877d2c77	163	}
andrewbonney	0:18dd877d2c77	164	}
andrewbonney	0:18dd877d2c77	165
andrewbonney	0:18dd877d2c77	166	switch (pcb->state) {
andrewbonney	0:18dd877d2c77	167	case CLOSED:
andrewbonney	0:18dd877d2c77	168	/* Closing a pcb in the CLOSED state might seem erroneous,
andrewbonney	0:18dd877d2c77	169	* however, it is in this state once allocated and as yet unused
andrewbonney	0:18dd877d2c77	170	* and the user needs some way to free it should the need arise.
andrewbonney	0:18dd877d2c77	171	* Calling tcp_close() with a pcb that has already been closed, (i.e. twice)
andrewbonney	0:18dd877d2c77	172	* or for a pcb that has been used and then entered the CLOSED state
andrewbonney	0:18dd877d2c77	173	* is erroneous, but this should never happen as the pcb has in those cases
andrewbonney	0:18dd877d2c77	174	* been freed, and so any remaining handles are bogus. */
andrewbonney	0:18dd877d2c77	175	err = ERR_OK;
andrewbonney	0:18dd877d2c77	176	TCP_RMV(&tcp_bound_pcbs, pcb);
andrewbonney	0:18dd877d2c77	177	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	178	pcb = NULL;
andrewbonney	0:18dd877d2c77	179	break;
andrewbonney	0:18dd877d2c77	180	case LISTEN:
andrewbonney	0:18dd877d2c77	181	err = ERR_OK;
andrewbonney	0:18dd877d2c77	182	tcp_pcb_remove(&tcp_listen_pcbs.pcbs, pcb);
andrewbonney	0:18dd877d2c77	183	memp_free(MEMP_TCP_PCB_LISTEN, pcb);
andrewbonney	0:18dd877d2c77	184	pcb = NULL;
andrewbonney	0:18dd877d2c77	185	break;
andrewbonney	0:18dd877d2c77	186	case SYN_SENT:
andrewbonney	0:18dd877d2c77	187	err = ERR_OK;
andrewbonney	0:18dd877d2c77	188	tcp_pcb_remove(&tcp_active_pcbs, pcb);
andrewbonney	0:18dd877d2c77	189	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	190	pcb = NULL;
andrewbonney	0:18dd877d2c77	191	snmp_inc_tcpattemptfails();
andrewbonney	0:18dd877d2c77	192	break;
andrewbonney	0:18dd877d2c77	193	case SYN_RCVD:
andrewbonney	0:18dd877d2c77	194	err = tcp_send_fin(pcb);
andrewbonney	0:18dd877d2c77	195	if (err == ERR_OK) {
andrewbonney	0:18dd877d2c77	196	snmp_inc_tcpattemptfails();
andrewbonney	0:18dd877d2c77	197	pcb->state = FIN_WAIT_1;
andrewbonney	0:18dd877d2c77	198	}
andrewbonney	0:18dd877d2c77	199	break;
andrewbonney	0:18dd877d2c77	200	case ESTABLISHED:
andrewbonney	0:18dd877d2c77	201	err = tcp_send_fin(pcb);
andrewbonney	0:18dd877d2c77	202	if (err == ERR_OK) {
andrewbonney	0:18dd877d2c77	203	snmp_inc_tcpestabresets();
andrewbonney	0:18dd877d2c77	204	pcb->state = FIN_WAIT_1;
andrewbonney	0:18dd877d2c77	205	}
andrewbonney	0:18dd877d2c77	206	break;
andrewbonney	0:18dd877d2c77	207	case CLOSE_WAIT:
andrewbonney	0:18dd877d2c77	208	err = tcp_send_fin(pcb);
andrewbonney	0:18dd877d2c77	209	if (err == ERR_OK) {
andrewbonney	0:18dd877d2c77	210	snmp_inc_tcpestabresets();
andrewbonney	0:18dd877d2c77	211	pcb->state = LAST_ACK;
andrewbonney	0:18dd877d2c77	212	}
andrewbonney	0:18dd877d2c77	213	break;
andrewbonney	0:18dd877d2c77	214	default:
andrewbonney	0:18dd877d2c77	215	/* Has already been closed, do nothing. */
andrewbonney	0:18dd877d2c77	216	err = ERR_OK;
andrewbonney	0:18dd877d2c77	217	pcb = NULL;
andrewbonney	0:18dd877d2c77	218	break;
andrewbonney	0:18dd877d2c77	219	}
andrewbonney	0:18dd877d2c77	220
andrewbonney	0:18dd877d2c77	221	if (pcb != NULL && err == ERR_OK) {
andrewbonney	0:18dd877d2c77	222	/* To ensure all data has been sent when tcp_close returns, we have
andrewbonney	0:18dd877d2c77	223	to make sure tcp_output doesn't fail.
andrewbonney	0:18dd877d2c77	224	Since we don't really have to ensure all data has been sent when tcp_close
andrewbonney	0:18dd877d2c77	225	returns (unsent data is sent from tcp timer functions, also), we don't care
andrewbonney	0:18dd877d2c77	226	for the return value of tcp_output for now. */
andrewbonney	0:18dd877d2c77	227	/* @todo: When implementing SO_LINGER, this must be changed somehow:
andrewbonney	0:18dd877d2c77	228	If SOF_LINGER is set, the data should be sent and acked before close returns.
andrewbonney	0:18dd877d2c77	229	This can only be valid for sequential APIs, not for the raw API. */
andrewbonney	0:18dd877d2c77	230	tcp_output(pcb);
andrewbonney	0:18dd877d2c77	231	}
andrewbonney	0:18dd877d2c77	232	return err;
andrewbonney	0:18dd877d2c77	233	}
andrewbonney	0:18dd877d2c77	234
andrewbonney	0:18dd877d2c77	235	/**
andrewbonney	0:18dd877d2c77	236	* Closes the connection held by the PCB.
andrewbonney	0:18dd877d2c77	237	*
andrewbonney	0:18dd877d2c77	238	* Listening pcbs are freed and may not be referenced any more.
andrewbonney	0:18dd877d2c77	239	* Connection pcbs are freed if not yet connected and may not be referenced
andrewbonney	0:18dd877d2c77	240	* any more. If a connection is established (at least SYN received or in
andrewbonney	0:18dd877d2c77	241	* a closing state), the connection is closed, and put in a closing state.
andrewbonney	0:18dd877d2c77	242	* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
andrewbonney	0:18dd877d2c77	243	* unsafe to reference it (unless an error is returned).
andrewbonney	0:18dd877d2c77	244	*
andrewbonney	0:18dd877d2c77	245	* @param pcb the tcp_pcb to close
andrewbonney	0:18dd877d2c77	246	* @return ERR_OK if connection has been closed
andrewbonney	0:18dd877d2c77	247	* another err_t if closing failed and pcb is not freed
andrewbonney	0:18dd877d2c77	248	*/
andrewbonney	0:18dd877d2c77	249	err_t
andrewbonney	0:18dd877d2c77	250	tcp_close(struct tcp_pcb *pcb)
andrewbonney	0:18dd877d2c77	251	{
andrewbonney	0:18dd877d2c77	252	#if TCP_DEBUG
andrewbonney	0:18dd877d2c77	253	LWIP_DEBUGF(TCP_DEBUG, ("tcp_close: closing in "));
andrewbonney	0:18dd877d2c77	254	tcp_debug_print_state(pcb->state);
andrewbonney	0:18dd877d2c77	255	#endif /* TCP_DEBUG */
andrewbonney	0:18dd877d2c77	256
andrewbonney	0:18dd877d2c77	257	if (pcb->state != LISTEN) {
andrewbonney	0:18dd877d2c77	258	/* Set a flag not to receive any more data... */
andrewbonney	0:18dd877d2c77	259	pcb->flags \|= TF_RXCLOSED;
andrewbonney	0:18dd877d2c77	260	}
andrewbonney	0:18dd877d2c77	261	/* ... and close */
andrewbonney	0:18dd877d2c77	262	return tcp_close_shutdown(pcb, 1);
andrewbonney	0:18dd877d2c77	263	}
andrewbonney	0:18dd877d2c77	264
andrewbonney	0:18dd877d2c77	265	/**
andrewbonney	0:18dd877d2c77	266	* Causes all or part of a full-duplex connection of this PCB to be shut down.
andrewbonney	0:18dd877d2c77	267	* This doesn't deallocate the PCB!
andrewbonney	0:18dd877d2c77	268	*
andrewbonney	0:18dd877d2c77	269	* @param pcb PCB to shutdown
andrewbonney	0:18dd877d2c77	270	* @param shut_rx shut down receive side if this is != 0
andrewbonney	0:18dd877d2c77	271	* @param shut_tx shut down send side if this is != 0
andrewbonney	0:18dd877d2c77	272	* @return ERR_OK if shutdown succeeded (or the PCB has already been shut down)
andrewbonney	0:18dd877d2c77	273	* another err_t on error.
andrewbonney	0:18dd877d2c77	274	*/
andrewbonney	0:18dd877d2c77	275	err_t
andrewbonney	0:18dd877d2c77	276	tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx)
andrewbonney	0:18dd877d2c77	277	{
andrewbonney	0:18dd877d2c77	278	if (pcb->state == LISTEN) {
andrewbonney	0:18dd877d2c77	279	return ERR_CONN;
andrewbonney	0:18dd877d2c77	280	}
andrewbonney	0:18dd877d2c77	281	if (shut_rx) {
andrewbonney	0:18dd877d2c77	282	/* shut down the receive side: free buffered data... */
andrewbonney	0:18dd877d2c77	283	if (pcb->refused_data != NULL) {
andrewbonney	0:18dd877d2c77	284	pbuf_free(pcb->refused_data);
andrewbonney	0:18dd877d2c77	285	pcb->refused_data = NULL;
andrewbonney	0:18dd877d2c77	286	}
andrewbonney	0:18dd877d2c77	287	/* ... and set a flag not to receive any more data */
andrewbonney	0:18dd877d2c77	288	pcb->flags \|= TF_RXCLOSED;
andrewbonney	0:18dd877d2c77	289	}
andrewbonney	0:18dd877d2c77	290	if (shut_tx) {
andrewbonney	0:18dd877d2c77	291	/* This can't happen twice since if it succeeds, the pcb's state is changed.
andrewbonney	0:18dd877d2c77	292	Only close in these states as the others directly deallocate the PCB */
andrewbonney	0:18dd877d2c77	293	switch (pcb->state) {
andrewbonney	0:18dd877d2c77	294	case SYN_RCVD:
andrewbonney	0:18dd877d2c77	295	case ESTABLISHED:
andrewbonney	0:18dd877d2c77	296	case CLOSE_WAIT:
andrewbonney	0:18dd877d2c77	297	return tcp_close_shutdown(pcb, 0);
andrewbonney	0:18dd877d2c77	298	default:
andrewbonney	0:18dd877d2c77	299	/* don't shut down other states */
andrewbonney	0:18dd877d2c77	300	break;
andrewbonney	0:18dd877d2c77	301	}
andrewbonney	0:18dd877d2c77	302	}
andrewbonney	0:18dd877d2c77	303	/* @todo: return another err_t if not in correct state or already shut? */
andrewbonney	0:18dd877d2c77	304	return ERR_OK;
andrewbonney	0:18dd877d2c77	305	}
andrewbonney	0:18dd877d2c77	306
andrewbonney	0:18dd877d2c77	307	/**
andrewbonney	0:18dd877d2c77	308	* Abandons a connection and optionally sends a RST to the remote
andrewbonney	0:18dd877d2c77	309	* host. Deletes the local protocol control block. This is done when
andrewbonney	0:18dd877d2c77	310	* a connection is killed because of shortage of memory.
andrewbonney	0:18dd877d2c77	311	*
andrewbonney	0:18dd877d2c77	312	* @param pcb the tcp_pcb to abort
andrewbonney	0:18dd877d2c77	313	* @param reset boolean to indicate whether a reset should be sent
andrewbonney	0:18dd877d2c77	314	*/
andrewbonney	0:18dd877d2c77	315	void
andrewbonney	0:18dd877d2c77	316	tcp_abandon(struct tcp_pcb *pcb, int reset)
andrewbonney	0:18dd877d2c77	317	{
andrewbonney	0:18dd877d2c77	318	u32_t seqno, ackno;
andrewbonney	0:18dd877d2c77	319	u16_t remote_port, local_port;
andrewbonney	0:18dd877d2c77	320	ip_addr_t remote_ip, local_ip;
andrewbonney	0:18dd877d2c77	321	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	322	tcp_err_fn errf;
andrewbonney	0:18dd877d2c77	323	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	324	void *errf_arg;
andrewbonney	0:18dd877d2c77	325
andrewbonney	0:18dd877d2c77	326	/* pcb->state LISTEN not allowed here */
andrewbonney	0:18dd877d2c77	327	LWIP_ASSERT("don't call tcp_abort/tcp_abandon for listen-pcbs",
andrewbonney	0:18dd877d2c77	328	pcb->state != LISTEN);
andrewbonney	0:18dd877d2c77	329	/* Figure out on which TCP PCB list we are, and remove us. If we
andrewbonney	0:18dd877d2c77	330	are in an active state, call the receive function associated with
andrewbonney	0:18dd877d2c77	331	the PCB with a NULL argument, and send an RST to the remote end. */
andrewbonney	0:18dd877d2c77	332	if (pcb->state == TIME_WAIT) {
andrewbonney	0:18dd877d2c77	333	tcp_pcb_remove(&tcp_tw_pcbs, pcb);
andrewbonney	0:18dd877d2c77	334	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	335	} else {
andrewbonney	0:18dd877d2c77	336	seqno = pcb->snd_nxt;
andrewbonney	0:18dd877d2c77	337	ackno = pcb->rcv_nxt;
andrewbonney	0:18dd877d2c77	338	ip_addr_copy(local_ip, pcb->local_ip);
andrewbonney	0:18dd877d2c77	339	ip_addr_copy(remote_ip, pcb->remote_ip);
andrewbonney	0:18dd877d2c77	340	local_port = pcb->local_port;
andrewbonney	0:18dd877d2c77	341	remote_port = pcb->remote_port;
andrewbonney	0:18dd877d2c77	342	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	343	errf = pcb->errf;
andrewbonney	0:18dd877d2c77	344	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	345	errf_arg = pcb->callback_arg;
andrewbonney	0:18dd877d2c77	346	tcp_pcb_remove(&tcp_active_pcbs, pcb);
andrewbonney	0:18dd877d2c77	347	if (pcb->unacked != NULL) {
andrewbonney	0:18dd877d2c77	348	tcp_segs_free(pcb->unacked);
andrewbonney	0:18dd877d2c77	349	}
andrewbonney	0:18dd877d2c77	350	if (pcb->unsent != NULL) {
andrewbonney	0:18dd877d2c77	351	tcp_segs_free(pcb->unsent);
andrewbonney	0:18dd877d2c77	352	}
andrewbonney	0:18dd877d2c77	353	#if TCP_QUEUE_OOSEQ
andrewbonney	0:18dd877d2c77	354	if (pcb->ooseq != NULL) {
andrewbonney	0:18dd877d2c77	355	tcp_segs_free(pcb->ooseq);
andrewbonney	0:18dd877d2c77	356	}
andrewbonney	0:18dd877d2c77	357	#endif /* TCP_QUEUE_OOSEQ */
andrewbonney	0:18dd877d2c77	358	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	359	TCP_EVENT_ERR(errf, errf_arg, ERR_ABRT);
andrewbonney	0:18dd877d2c77	360	if (reset) {
andrewbonney	0:18dd877d2c77	361	LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_abandon: sending RST\n"));
andrewbonney	0:18dd877d2c77	362	tcp_rst(seqno, ackno, &local_ip, &remote_ip, local_port, remote_port);
andrewbonney	0:18dd877d2c77	363	}
andrewbonney	0:18dd877d2c77	364	}
andrewbonney	0:18dd877d2c77	365	}
andrewbonney	0:18dd877d2c77	366
andrewbonney	0:18dd877d2c77	367	/**
andrewbonney	0:18dd877d2c77	368	* Aborts the connection by sending a RST (reset) segment to the remote
andrewbonney	0:18dd877d2c77	369	* host. The pcb is deallocated. This function never fails.
andrewbonney	0:18dd877d2c77	370	*
andrewbonney	0:18dd877d2c77	371	* ATTENTION: When calling this from one of the TCP callbacks, make
andrewbonney	0:18dd877d2c77	372	* sure you always return ERR_ABRT (and never return ERR_ABRT otherwise
andrewbonney	0:18dd877d2c77	373	* or you will risk accessing deallocated memory or memory leaks!
andrewbonney	0:18dd877d2c77	374	*
andrewbonney	0:18dd877d2c77	375	* @param pcb the tcp pcb to abort
andrewbonney	0:18dd877d2c77	376	*/
andrewbonney	0:18dd877d2c77	377	void
andrewbonney	0:18dd877d2c77	378	tcp_abort(struct tcp_pcb *pcb)
andrewbonney	0:18dd877d2c77	379	{
andrewbonney	0:18dd877d2c77	380	tcp_abandon(pcb, 1);
andrewbonney	0:18dd877d2c77	381	}
andrewbonney	0:18dd877d2c77	382
andrewbonney	0:18dd877d2c77	383	/**
andrewbonney	0:18dd877d2c77	384	* Binds the connection to a local portnumber and IP address. If the
andrewbonney	0:18dd877d2c77	385	* IP address is not given (i.e., ipaddr == NULL), the IP address of
andrewbonney	0:18dd877d2c77	386	* the outgoing network interface is used instead.
andrewbonney	0:18dd877d2c77	387	*
andrewbonney	0:18dd877d2c77	388	* @param pcb the tcp_pcb to bind (no check is done whether this pcb is
andrewbonney	0:18dd877d2c77	389	* already bound!)
andrewbonney	0:18dd877d2c77	390	* @param ipaddr the local ip address to bind to (use IP_ADDR_ANY to bind
andrewbonney	0:18dd877d2c77	391	* to any local address
andrewbonney	0:18dd877d2c77	392	* @param port the local port to bind to
andrewbonney	0:18dd877d2c77	393	* @return ERR_USE if the port is already in use
andrewbonney	0:18dd877d2c77	394	* ERR_OK if bound
andrewbonney	0:18dd877d2c77	395	*/
andrewbonney	0:18dd877d2c77	396	err_t
andrewbonney	0:18dd877d2c77	397	tcp_bind(struct tcp_pcb pcb, ip_addr_t ipaddr, u16_t port)
andrewbonney	0:18dd877d2c77	398	{
andrewbonney	0:18dd877d2c77	399	int i;
andrewbonney	0:18dd877d2c77	400	int max_pcb_list = NUM_TCP_PCB_LISTS;
andrewbonney	0:18dd877d2c77	401	struct tcp_pcb *cpcb;
andrewbonney	0:18dd877d2c77	402
andrewbonney	0:18dd877d2c77	403	LWIP_ERROR("tcp_bind: can only bind in state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
andrewbonney	0:18dd877d2c77	404
andrewbonney	0:18dd877d2c77	405	#if SO_REUSE
andrewbonney	0:18dd877d2c77	406	/* Unless the REUSEADDR flag is set,
andrewbonney	0:18dd877d2c77	407	we have to check the pcbs in TIME-WAIT state, also.
andrewbonney	0:18dd877d2c77	408	We do not dump TIME_WAIT pcb's; they can still be matched by incoming
andrewbonney	0:18dd877d2c77	409	packets using both local and remote IP addresses and ports to distinguish.
andrewbonney	0:18dd877d2c77	410	*/
andrewbonney	0:18dd877d2c77	411	#if SO_REUSE
andrewbonney	0:18dd877d2c77	412	if ((pcb->so_options & SOF_REUSEADDR) != 0) {
andrewbonney	0:18dd877d2c77	413	max_pcb_list = NUM_TCP_PCB_LISTS_NO_TIME_WAIT;
andrewbonney	0:18dd877d2c77	414	}
andrewbonney	0:18dd877d2c77	415	#endif /* SO_REUSE */
andrewbonney	0:18dd877d2c77	416	#endif /* SO_REUSE */
andrewbonney	0:18dd877d2c77	417
andrewbonney	0:18dd877d2c77	418	if (port == 0) {
andrewbonney	0:18dd877d2c77	419	port = tcp_new_port();
andrewbonney	0:18dd877d2c77	420	}
andrewbonney	0:18dd877d2c77	421
andrewbonney	0:18dd877d2c77	422	/* Check if the address already is in use (on all lists) */
andrewbonney	0:18dd877d2c77	423	for (i = 0; i < max_pcb_list; i++) {
andrewbonney	0:18dd877d2c77	424	for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
andrewbonney	0:18dd877d2c77	425	if (cpcb->local_port == port) {
andrewbonney	0:18dd877d2c77	426	#if SO_REUSE
andrewbonney	0:18dd877d2c77	427	/* Omit checking for the same port if both pcbs have REUSEADDR set.
andrewbonney	0:18dd877d2c77	428	For SO_REUSEADDR, the duplicate-check for a 5-tuple is done in
andrewbonney	0:18dd877d2c77	429	tcp_connect. */
andrewbonney	0:18dd877d2c77	430	if (((pcb->so_options & SOF_REUSEADDR) == 0) \|\|
andrewbonney	0:18dd877d2c77	431	((cpcb->so_options & SOF_REUSEADDR) == 0))
andrewbonney	0:18dd877d2c77	432	#endif /* SO_REUSE */
andrewbonney	0:18dd877d2c77	433	{
andrewbonney	0:18dd877d2c77	434	if (ip_addr_isany(&(cpcb->local_ip)) \|\|
andrewbonney	0:18dd877d2c77	435	ip_addr_isany(ipaddr) \|\|
andrewbonney	0:18dd877d2c77	436	ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
andrewbonney	0:18dd877d2c77	437	return ERR_USE;
andrewbonney	0:18dd877d2c77	438	}
andrewbonney	0:18dd877d2c77	439	}
andrewbonney	0:18dd877d2c77	440	}
andrewbonney	0:18dd877d2c77	441	}
andrewbonney	0:18dd877d2c77	442	}
andrewbonney	0:18dd877d2c77	443
andrewbonney	0:18dd877d2c77	444	if (!ip_addr_isany(ipaddr)) {
andrewbonney	0:18dd877d2c77	445	pcb->local_ip = *ipaddr;
andrewbonney	0:18dd877d2c77	446	}
andrewbonney	0:18dd877d2c77	447	pcb->local_port = port;
andrewbonney	0:18dd877d2c77	448	TCP_REG(&tcp_bound_pcbs, pcb);
andrewbonney	0:18dd877d2c77	449	LWIP_DEBUGF(TCP_DEBUG, ("tcp_bind: bind to port %"U16_F"\n", port));
andrewbonney	0:18dd877d2c77	450	return ERR_OK;
andrewbonney	0:18dd877d2c77	451	}
andrewbonney	0:18dd877d2c77	452	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	453	/**
andrewbonney	0:18dd877d2c77	454	* Default accept callback if no accept callback is specified by the user.
andrewbonney	0:18dd877d2c77	455	*/
andrewbonney	0:18dd877d2c77	456	static err_t
andrewbonney	0:18dd877d2c77	457	tcp_accept_null(void arg, struct tcp_pcb pcb, err_t err)
andrewbonney	0:18dd877d2c77	458	{
andrewbonney	0:18dd877d2c77	459	LWIP_UNUSED_ARG(arg);
andrewbonney	0:18dd877d2c77	460	LWIP_UNUSED_ARG(pcb);
andrewbonney	0:18dd877d2c77	461	LWIP_UNUSED_ARG(err);
andrewbonney	0:18dd877d2c77	462
andrewbonney	0:18dd877d2c77	463	return ERR_ABRT;
andrewbonney	0:18dd877d2c77	464	}
andrewbonney	0:18dd877d2c77	465	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	466
andrewbonney	0:18dd877d2c77	467	/**
andrewbonney	0:18dd877d2c77	468	* Set the state of the connection to be LISTEN, which means that it
andrewbonney	0:18dd877d2c77	469	* is able to accept incoming connections. The protocol control block
andrewbonney	0:18dd877d2c77	470	* is reallocated in order to consume less memory. Setting the
andrewbonney	0:18dd877d2c77	471	* connection to LISTEN is an irreversible process.
andrewbonney	0:18dd877d2c77	472	*
andrewbonney	0:18dd877d2c77	473	* @param pcb the original tcp_pcb
andrewbonney	0:18dd877d2c77	474	* @param backlog the incoming connections queue limit
andrewbonney	0:18dd877d2c77	475	* @return tcp_pcb used for listening, consumes less memory.
andrewbonney	0:18dd877d2c77	476	*
andrewbonney	0:18dd877d2c77	477	* @note The original tcp_pcb is freed. This function therefore has to be
andrewbonney	0:18dd877d2c77	478	* called like this:
andrewbonney	0:18dd877d2c77	479	* tpcb = tcp_listen(tpcb);
andrewbonney	0:18dd877d2c77	480	*/
andrewbonney	0:18dd877d2c77	481	struct tcp_pcb *
andrewbonney	0:18dd877d2c77	482	tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
andrewbonney	0:18dd877d2c77	483	{
andrewbonney	0:18dd877d2c77	484	struct tcp_pcb_listen *lpcb;
andrewbonney	0:18dd877d2c77	485
andrewbonney	0:18dd877d2c77	486	LWIP_UNUSED_ARG(backlog);
andrewbonney	0:18dd877d2c77	487	LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
andrewbonney	0:18dd877d2c77	488
andrewbonney	0:18dd877d2c77	489	/* already listening? */
andrewbonney	0:18dd877d2c77	490	if (pcb->state == LISTEN) {
andrewbonney	0:18dd877d2c77	491	return pcb;
andrewbonney	0:18dd877d2c77	492	}
andrewbonney	0:18dd877d2c77	493	#if SO_REUSE
andrewbonney	0:18dd877d2c77	494	if ((pcb->so_options & SOF_REUSEADDR) != 0) {
andrewbonney	0:18dd877d2c77	495	/* Since SOF_REUSEADDR allows reusing a local address before the pcb's usage
andrewbonney	0:18dd877d2c77	496	is declared (listen-/connection-pcb), we have to make sure now that
andrewbonney	0:18dd877d2c77	497	this port is only used once for every local IP. */
andrewbonney	0:18dd877d2c77	498	for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
andrewbonney	0:18dd877d2c77	499	if (lpcb->local_port == pcb->local_port) {
andrewbonney	0:18dd877d2c77	500	if (ip_addr_cmp(&lpcb->local_ip, &pcb->local_ip)) {
andrewbonney	0:18dd877d2c77	501	/* this address/port is already used */
andrewbonney	0:18dd877d2c77	502	return NULL;
andrewbonney	0:18dd877d2c77	503	}
andrewbonney	0:18dd877d2c77	504	}
andrewbonney	0:18dd877d2c77	505	}
andrewbonney	0:18dd877d2c77	506	}
andrewbonney	0:18dd877d2c77	507	#endif /* SO_REUSE */
andrewbonney	0:18dd877d2c77	508	lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);
andrewbonney	0:18dd877d2c77	509	if (lpcb == NULL) {
andrewbonney	0:18dd877d2c77	510	return NULL;
andrewbonney	0:18dd877d2c77	511	}
andrewbonney	0:18dd877d2c77	512	lpcb->callback_arg = pcb->callback_arg;
andrewbonney	0:18dd877d2c77	513	lpcb->local_port = pcb->local_port;
andrewbonney	0:18dd877d2c77	514	lpcb->state = LISTEN;
andrewbonney	0:18dd877d2c77	515	lpcb->prio = pcb->prio;
andrewbonney	0:18dd877d2c77	516	lpcb->so_options = pcb->so_options;
andrewbonney	0:18dd877d2c77	517	lpcb->so_options \|= SOF_ACCEPTCONN;
andrewbonney	0:18dd877d2c77	518	lpcb->ttl = pcb->ttl;
andrewbonney	0:18dd877d2c77	519	lpcb->tos = pcb->tos;
andrewbonney	0:18dd877d2c77	520	ip_addr_copy(lpcb->local_ip, pcb->local_ip);
andrewbonney	0:18dd877d2c77	521	TCP_RMV(&tcp_bound_pcbs, pcb);
andrewbonney	0:18dd877d2c77	522	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	523	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	524	lpcb->accept = tcp_accept_null;
andrewbonney	0:18dd877d2c77	525	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	526	#if TCP_LISTEN_BACKLOG
andrewbonney	0:18dd877d2c77	527	lpcb->accepts_pending = 0;
andrewbonney	0:18dd877d2c77	528	lpcb->backlog = (backlog ? backlog : 1);
andrewbonney	0:18dd877d2c77	529	#endif /* TCP_LISTEN_BACKLOG */
andrewbonney	0:18dd877d2c77	530	TCP_REG(&tcp_listen_pcbs.pcbs, (struct tcp_pcb *)lpcb);
andrewbonney	0:18dd877d2c77	531	return (struct tcp_pcb *)lpcb;
andrewbonney	0:18dd877d2c77	532	}
andrewbonney	0:18dd877d2c77	533
andrewbonney	0:18dd877d2c77	534	/**
andrewbonney	0:18dd877d2c77	535	* Update the state that tracks the available window space to advertise.
andrewbonney	0:18dd877d2c77	536	*
andrewbonney	0:18dd877d2c77	537	* Returns how much extra window would be advertised if we sent an
andrewbonney	0:18dd877d2c77	538	* update now.
andrewbonney	0:18dd877d2c77	539	*/
andrewbonney	0:18dd877d2c77	540	u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb)
andrewbonney	0:18dd877d2c77	541	{
andrewbonney	0:18dd877d2c77	542	u32_t new_right_edge = pcb->rcv_nxt + pcb->rcv_wnd;
andrewbonney	0:18dd877d2c77	543
andrewbonney	0:18dd877d2c77	544	if (TCP_SEQ_GEQ(new_right_edge, pcb->rcv_ann_right_edge + LWIP_MIN((TCP_WND / 2), pcb->mss))) {
andrewbonney	0:18dd877d2c77	545	/* we can advertise more window */
andrewbonney	0:18dd877d2c77	546	pcb->rcv_ann_wnd = pcb->rcv_wnd;
andrewbonney	0:18dd877d2c77	547	return new_right_edge - pcb->rcv_ann_right_edge;
andrewbonney	0:18dd877d2c77	548	} else {
andrewbonney	0:18dd877d2c77	549	if (TCP_SEQ_GT(pcb->rcv_nxt, pcb->rcv_ann_right_edge)) {
andrewbonney	0:18dd877d2c77	550	/* Can happen due to other end sending out of advertised window,
andrewbonney	0:18dd877d2c77	551	* but within actual available (but not yet advertised) window */
andrewbonney	0:18dd877d2c77	552	pcb->rcv_ann_wnd = 0;
andrewbonney	0:18dd877d2c77	553	} else {
andrewbonney	0:18dd877d2c77	554	/* keep the right edge of window constant */
andrewbonney	0:18dd877d2c77	555	u32_t new_rcv_ann_wnd = pcb->rcv_ann_right_edge - pcb->rcv_nxt;
andrewbonney	0:18dd877d2c77	556	LWIP_ASSERT("new_rcv_ann_wnd <= 0xffff", new_rcv_ann_wnd <= 0xffff);
andrewbonney	0:18dd877d2c77	557	pcb->rcv_ann_wnd = (u16_t)new_rcv_ann_wnd;
andrewbonney	0:18dd877d2c77	558	}
andrewbonney	0:18dd877d2c77	559	return 0;
andrewbonney	0:18dd877d2c77	560	}
andrewbonney	0:18dd877d2c77	561	}
andrewbonney	0:18dd877d2c77	562
andrewbonney	0:18dd877d2c77	563	/**
andrewbonney	0:18dd877d2c77	564	* This function should be called by the application when it has
andrewbonney	0:18dd877d2c77	565	* processed the data. The purpose is to advertise a larger window
andrewbonney	0:18dd877d2c77	566	* when the data has been processed.
andrewbonney	0:18dd877d2c77	567	*
andrewbonney	0:18dd877d2c77	568	* @param pcb the tcp_pcb for which data is read
andrewbonney	0:18dd877d2c77	569	* @param len the amount of bytes that have been read by the application
andrewbonney	0:18dd877d2c77	570	*/
andrewbonney	0:18dd877d2c77	571	void
andrewbonney	0:18dd877d2c77	572	tcp_recved(struct tcp_pcb *pcb, u16_t len)
andrewbonney	0:18dd877d2c77	573	{
andrewbonney	0:18dd877d2c77	574	int wnd_inflation;
andrewbonney	0:18dd877d2c77	575
andrewbonney	0:18dd877d2c77	576	LWIP_ASSERT("tcp_recved: len would wrap rcv_wnd\n",
andrewbonney	0:18dd877d2c77	577	len <= 0xffff - pcb->rcv_wnd );
andrewbonney	0:18dd877d2c77	578
andrewbonney	0:18dd877d2c77	579	pcb->rcv_wnd += len;
andrewbonney	0:18dd877d2c77	580	if (pcb->rcv_wnd > TCP_WND) {
andrewbonney	0:18dd877d2c77	581	pcb->rcv_wnd = TCP_WND;
andrewbonney	0:18dd877d2c77	582	}
andrewbonney	0:18dd877d2c77	583
andrewbonney	0:18dd877d2c77	584	wnd_inflation = tcp_update_rcv_ann_wnd(pcb);
andrewbonney	0:18dd877d2c77	585
andrewbonney	0:18dd877d2c77	586	/* If the change in the right edge of window is significant (default
andrewbonney	0:18dd877d2c77	587	* watermark is TCP_WND/4), then send an explicit update now.
andrewbonney	0:18dd877d2c77	588	* Otherwise wait for a packet to be sent in the normal course of
andrewbonney	0:18dd877d2c77	589	* events (or more window to be available later) */
andrewbonney	0:18dd877d2c77	590	if (wnd_inflation >= TCP_WND_UPDATE_THRESHOLD) {
andrewbonney	0:18dd877d2c77	591	tcp_ack_now(pcb);
andrewbonney	0:18dd877d2c77	592	tcp_output(pcb);
andrewbonney	0:18dd877d2c77	593	}
andrewbonney	0:18dd877d2c77	594
andrewbonney	0:18dd877d2c77	595	LWIP_DEBUGF(TCP_DEBUG, ("tcp_recved: recveived %"U16_F" bytes, wnd %"U16_F" (%"U16_F").\n",
andrewbonney	0:18dd877d2c77	596	len, pcb->rcv_wnd, TCP_WND - pcb->rcv_wnd));
andrewbonney	0:18dd877d2c77	597	}
andrewbonney	0:18dd877d2c77	598
andrewbonney	0:18dd877d2c77	599	/**
andrewbonney	0:18dd877d2c77	600	* A nastly hack featuring 'goto' statements that allocates a
andrewbonney	0:18dd877d2c77	601	* new TCP local port.
andrewbonney	0:18dd877d2c77	602	*
andrewbonney	0:18dd877d2c77	603	* @return a new (free) local TCP port number
andrewbonney	0:18dd877d2c77	604	*/
andrewbonney	0:18dd877d2c77	605	static u16_t
andrewbonney	0:18dd877d2c77	606	tcp_new_port(void)
andrewbonney	0:18dd877d2c77	607	{
andrewbonney	0:18dd877d2c77	608	int i;
andrewbonney	0:18dd877d2c77	609	struct tcp_pcb *pcb;
andrewbonney	0:18dd877d2c77	610	#ifndef TCP_LOCAL_PORT_RANGE_START
andrewbonney	0:18dd877d2c77	611	#define TCP_LOCAL_PORT_RANGE_START 4096
andrewbonney	0:18dd877d2c77	612	#define TCP_LOCAL_PORT_RANGE_END 0x7fff
andrewbonney	0:18dd877d2c77	613	#endif
andrewbonney	0:18dd877d2c77	614	static u16_t port = TCP_LOCAL_PORT_RANGE_START;
andrewbonney	0:18dd877d2c77	615
andrewbonney	0:18dd877d2c77	616	again:
andrewbonney	0:18dd877d2c77	617	if (++port > TCP_LOCAL_PORT_RANGE_END) {
andrewbonney	0:18dd877d2c77	618	port = TCP_LOCAL_PORT_RANGE_START;
andrewbonney	0:18dd877d2c77	619	}
andrewbonney	0:18dd877d2c77	620	/* Check all PCB lists. */
andrewbonney	0:18dd877d2c77	621	for (i = 1; i < NUM_TCP_PCB_LISTS; i++) {
andrewbonney	0:18dd877d2c77	622	for(pcb = *tcp_pcb_lists[i]; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	623	if (pcb->local_port == port) {
andrewbonney	0:18dd877d2c77	624	goto again;
andrewbonney	0:18dd877d2c77	625	}
andrewbonney	0:18dd877d2c77	626	}
andrewbonney	0:18dd877d2c77	627	}
andrewbonney	0:18dd877d2c77	628	return port;
andrewbonney	0:18dd877d2c77	629	}
andrewbonney	0:18dd877d2c77	630
andrewbonney	0:18dd877d2c77	631	/**
andrewbonney	0:18dd877d2c77	632	* Connects to another host. The function given as the "connected"
andrewbonney	0:18dd877d2c77	633	* argument will be called when the connection has been established.
andrewbonney	0:18dd877d2c77	634	*
andrewbonney	0:18dd877d2c77	635	* @param pcb the tcp_pcb used to establish the connection
andrewbonney	0:18dd877d2c77	636	* @param ipaddr the remote ip address to connect to
andrewbonney	0:18dd877d2c77	637	* @param port the remote tcp port to connect to
andrewbonney	0:18dd877d2c77	638	* @param connected callback function to call when connected (or on error)
andrewbonney	0:18dd877d2c77	639	* @return ERR_VAL if invalid arguments are given
andrewbonney	0:18dd877d2c77	640	* ERR_OK if connect request has been sent
andrewbonney	0:18dd877d2c77	641	* other err_t values if connect request couldn't be sent
andrewbonney	0:18dd877d2c77	642	*/
andrewbonney	0:18dd877d2c77	643	err_t
andrewbonney	0:18dd877d2c77	644	tcp_connect(struct tcp_pcb pcb, ip_addr_t ipaddr, u16_t port,
andrewbonney	0:18dd877d2c77	645	tcp_connected_fn connected)
andrewbonney	0:18dd877d2c77	646	{
andrewbonney	0:18dd877d2c77	647	err_t ret;
andrewbonney	0:18dd877d2c77	648	u32_t iss;
andrewbonney	0:18dd877d2c77	649
andrewbonney	0:18dd877d2c77	650	LWIP_ERROR("tcp_connect: can only connected from state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
andrewbonney	0:18dd877d2c77	651
andrewbonney	0:18dd877d2c77	652	LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect to port %"U16_F"\n", port));
andrewbonney	0:18dd877d2c77	653	if (ipaddr != NULL) {
andrewbonney	0:18dd877d2c77	654	pcb->remote_ip = *ipaddr;
andrewbonney	0:18dd877d2c77	655	} else {
andrewbonney	0:18dd877d2c77	656	return ERR_VAL;
andrewbonney	0:18dd877d2c77	657	}
andrewbonney	0:18dd877d2c77	658	pcb->remote_port = port;
andrewbonney	0:18dd877d2c77	659
andrewbonney	0:18dd877d2c77	660	/* check if we have a route to the remote host */
andrewbonney	0:18dd877d2c77	661	if (ip_addr_isany(&(pcb->local_ip))) {
andrewbonney	0:18dd877d2c77	662	/* no local IP address set, yet. */
andrewbonney	0:18dd877d2c77	663	struct netif *netif = ip_route(&(pcb->remote_ip));
andrewbonney	0:18dd877d2c77	664	if (netif == NULL) {
andrewbonney	0:18dd877d2c77	665	/* Don't even try to send a SYN packet if we have no route
andrewbonney	0:18dd877d2c77	666	since that will fail. */
andrewbonney	0:18dd877d2c77	667	return ERR_RTE;
andrewbonney	0:18dd877d2c77	668	}
andrewbonney	0:18dd877d2c77	669	/* Use the netif's IP address as local address. */
andrewbonney	0:18dd877d2c77	670	ip_addr_copy(pcb->local_ip, netif->ip_addr);
andrewbonney	0:18dd877d2c77	671	}
andrewbonney	0:18dd877d2c77	672
andrewbonney	0:18dd877d2c77	673	if (pcb->local_port == 0) {
andrewbonney	0:18dd877d2c77	674	pcb->local_port = tcp_new_port();
andrewbonney	0:18dd877d2c77	675	}
andrewbonney	0:18dd877d2c77	676	#if SO_REUSE
andrewbonney	0:18dd877d2c77	677	if ((pcb->so_options & SOF_REUSEADDR) != 0) {
andrewbonney	0:18dd877d2c77	678	/* Since SOF_REUSEADDR allows reusing a local address, we have to make sure
andrewbonney	0:18dd877d2c77	679	now that the 5-tuple is unique. */
andrewbonney	0:18dd877d2c77	680	struct tcp_pcb *cpcb;
andrewbonney	0:18dd877d2c77	681	int i;
andrewbonney	0:18dd877d2c77	682	/* Don't check listen PCBs, check bound-, active- and TIME-WAIT PCBs. */
andrewbonney	0:18dd877d2c77	683	for (i = 1; i < NUM_TCP_PCB_LISTS; i++) {
andrewbonney	0:18dd877d2c77	684	for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
andrewbonney	0:18dd877d2c77	685	if ((cpcb->local_port == pcb->local_port) &&
andrewbonney	0:18dd877d2c77	686	(cpcb->remote_port == port) &&
andrewbonney	0:18dd877d2c77	687	ip_addr_cmp(&cpcb->local_ip, &pcb->local_ip) &&
andrewbonney	0:18dd877d2c77	688	ip_addr_cmp(&cpcb->remote_ip, ipaddr)) {
andrewbonney	0:18dd877d2c77	689	/* linux returns EISCONN here, but ERR_USE should be OK for us */
andrewbonney	0:18dd877d2c77	690	return ERR_USE;
andrewbonney	0:18dd877d2c77	691	}
andrewbonney	0:18dd877d2c77	692	}
andrewbonney	0:18dd877d2c77	693	}
andrewbonney	0:18dd877d2c77	694	}
andrewbonney	0:18dd877d2c77	695	#endif /* SO_REUSE */
andrewbonney	0:18dd877d2c77	696	iss = tcp_next_iss();
andrewbonney	0:18dd877d2c77	697	pcb->rcv_nxt = 0;
andrewbonney	0:18dd877d2c77	698	pcb->snd_nxt = iss;
andrewbonney	0:18dd877d2c77	699	pcb->lastack = iss - 1;
andrewbonney	0:18dd877d2c77	700	pcb->snd_lbb = iss - 1;
andrewbonney	0:18dd877d2c77	701	pcb->rcv_wnd = TCP_WND;
andrewbonney	0:18dd877d2c77	702	pcb->rcv_ann_wnd = TCP_WND;
andrewbonney	0:18dd877d2c77	703	pcb->rcv_ann_right_edge = pcb->rcv_nxt;
andrewbonney	0:18dd877d2c77	704	pcb->snd_wnd = TCP_WND;
andrewbonney	0:18dd877d2c77	705	/* As initial send MSS, we use TCP_MSS but limit it to 536.
andrewbonney	0:18dd877d2c77	706	The send MSS is updated when an MSS option is received. */
andrewbonney	0:18dd877d2c77	707	pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
andrewbonney	0:18dd877d2c77	708	#if TCP_CALCULATE_EFF_SEND_MSS
andrewbonney	0:18dd877d2c77	709	pcb->mss = tcp_eff_send_mss(pcb->mss, ipaddr);
andrewbonney	0:18dd877d2c77	710	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
andrewbonney	0:18dd877d2c77	711	pcb->cwnd = 1;
andrewbonney	0:18dd877d2c77	712	pcb->ssthresh = pcb->mss * 10;
andrewbonney	0:18dd877d2c77	713	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	714	pcb->connected = connected;
andrewbonney	0:18dd877d2c77	715	#else /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	716	LWIP_UNUSED_ARG(connected);
andrewbonney	0:18dd877d2c77	717	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	718
andrewbonney	0:18dd877d2c77	719	LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect: tcp_ticks=%"U32_F" iss=%"U32_F"\n", tcp_ticks, iss));
andrewbonney	0:18dd877d2c77	720
andrewbonney	0:18dd877d2c77	721	/* Send a SYN together with the MSS option. */
andrewbonney	0:18dd877d2c77	722	ret = tcp_enqueue_flags(pcb, TCP_SYN);
andrewbonney	0:18dd877d2c77	723	if (ret == ERR_OK) {
andrewbonney	0:18dd877d2c77	724	/* SYN segment was enqueued, changed the pcbs state now */
andrewbonney	0:18dd877d2c77	725	pcb->state = SYN_SENT;
andrewbonney	0:18dd877d2c77	726	TCP_RMV(&tcp_bound_pcbs, pcb);
andrewbonney	0:18dd877d2c77	727	TCP_REG(&tcp_active_pcbs, pcb);
andrewbonney	0:18dd877d2c77	728	snmp_inc_tcpactiveopens();
andrewbonney	0:18dd877d2c77	729
andrewbonney	0:18dd877d2c77	730	tcp_output(pcb);
andrewbonney	0:18dd877d2c77	731	}
andrewbonney	0:18dd877d2c77	732	return ret;
andrewbonney	0:18dd877d2c77	733	}
andrewbonney	0:18dd877d2c77	734
andrewbonney	0:18dd877d2c77	735	/**
andrewbonney	0:18dd877d2c77	736	* Called every 500 ms and implements the retransmission timer and the timer that
andrewbonney	0:18dd877d2c77	737	* removes PCBs that have been in TIME-WAIT for enough time. It also increments
andrewbonney	0:18dd877d2c77	738	* various timers such as the inactivity timer in each PCB.
andrewbonney	0:18dd877d2c77	739	*
andrewbonney	0:18dd877d2c77	740	* Automatically called from tcp_tmr().
andrewbonney	0:18dd877d2c77	741	*/
andrewbonney	0:18dd877d2c77	742	void
andrewbonney	0:18dd877d2c77	743	tcp_slowtmr(void)
andrewbonney	0:18dd877d2c77	744	{
andrewbonney	0:18dd877d2c77	745	struct tcp_pcb pcb, pcb2, *prev;
andrewbonney	0:18dd877d2c77	746	u16_t eff_wnd;
andrewbonney	0:18dd877d2c77	747	u8_t pcb_remove; /* flag if a PCB should be removed */
andrewbonney	0:18dd877d2c77	748	u8_t pcb_reset; /* flag if a RST should be sent when removing */
andrewbonney	0:18dd877d2c77	749	err_t err;
andrewbonney	0:18dd877d2c77	750
andrewbonney	0:18dd877d2c77	751	tcp_debug_print_pcbs(); //DG
andrewbonney	0:18dd877d2c77	752
andrewbonney	0:18dd877d2c77	753	err = ERR_OK;
andrewbonney	0:18dd877d2c77	754
andrewbonney	0:18dd877d2c77	755	++tcp_ticks;
andrewbonney	0:18dd877d2c77	756	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: tcp_ticks=%"U32_F"\n", tcp_ticks));
andrewbonney	0:18dd877d2c77	757
andrewbonney	0:18dd877d2c77	758	/* Steps through all of the active PCBs. */
andrewbonney	0:18dd877d2c77	759	prev = NULL;
andrewbonney	0:18dd877d2c77	760	pcb = tcp_active_pcbs;
andrewbonney	0:18dd877d2c77	761	if (pcb == NULL) {
andrewbonney	0:18dd877d2c77	762	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: no active pcbs\n"));
andrewbonney	0:18dd877d2c77	763	}
andrewbonney	0:18dd877d2c77	764	while (pcb != NULL) {
andrewbonney	0:18dd877d2c77	765	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: processing active pcb\n"));
andrewbonney	0:18dd877d2c77	766	LWIP_ASSERT("tcp_slowtmr: active pcb->state != CLOSED\n", pcb->state != CLOSED);
andrewbonney	0:18dd877d2c77	767	LWIP_ASSERT("tcp_slowtmr: active pcb->state != LISTEN\n", pcb->state != LISTEN);
andrewbonney	0:18dd877d2c77	768	LWIP_ASSERT("tcp_slowtmr: active pcb->state != TIME-WAIT\n", pcb->state != TIME_WAIT);
andrewbonney	0:18dd877d2c77	769
andrewbonney	0:18dd877d2c77	770	pcb_remove = 0;
andrewbonney	0:18dd877d2c77	771	pcb_reset = 0;
andrewbonney	0:18dd877d2c77	772
andrewbonney	0:18dd877d2c77	773	if (pcb->state == SYN_SENT && pcb->nrtx == TCP_SYNMAXRTX) {
andrewbonney	0:18dd877d2c77	774	++pcb_remove;
andrewbonney	0:18dd877d2c77	775	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max SYN retries reached\n"));
andrewbonney	0:18dd877d2c77	776	}
andrewbonney	0:18dd877d2c77	777	else if (pcb->nrtx == TCP_MAXRTX) {
andrewbonney	0:18dd877d2c77	778	++pcb_remove;
andrewbonney	0:18dd877d2c77	779	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max DATA retries reached\n"));
andrewbonney	0:18dd877d2c77	780	} else {
andrewbonney	0:18dd877d2c77	781	if (pcb->persist_backoff > 0) {
andrewbonney	0:18dd877d2c77	782	/* If snd_wnd is zero, use persist timer to send 1 byte probes
andrewbonney	0:18dd877d2c77	783	* instead of using the standard retransmission mechanism. */
andrewbonney	0:18dd877d2c77	784	pcb->persist_cnt++;
andrewbonney	0:18dd877d2c77	785	if (pcb->persist_cnt >= tcp_persist_backoff[pcb->persist_backoff-1]) {
andrewbonney	0:18dd877d2c77	786	pcb->persist_cnt = 0;
andrewbonney	0:18dd877d2c77	787	if (pcb->persist_backoff < sizeof(tcp_persist_backoff)) {
andrewbonney	0:18dd877d2c77	788	pcb->persist_backoff++;
andrewbonney	0:18dd877d2c77	789	}
andrewbonney	0:18dd877d2c77	790	tcp_zero_window_probe(pcb);
andrewbonney	0:18dd877d2c77	791	}
andrewbonney	0:18dd877d2c77	792	} else {
andrewbonney	0:18dd877d2c77	793	/* Increase the retransmission timer if it is running */
andrewbonney	0:18dd877d2c77	794	if(pcb->rtime >= 0)
andrewbonney	0:18dd877d2c77	795	++pcb->rtime;
andrewbonney	0:18dd877d2c77	796
andrewbonney	0:18dd877d2c77	797	if (pcb->unacked != NULL && pcb->rtime >= pcb->rto) {
andrewbonney	0:18dd877d2c77	798	/* Time for a retransmission. */
andrewbonney	0:18dd877d2c77	799	LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_slowtmr: rtime %"S16_F
andrewbonney	0:18dd877d2c77	800	" pcb->rto %"S16_F"\n",
andrewbonney	0:18dd877d2c77	801	pcb->rtime, pcb->rto));
andrewbonney	0:18dd877d2c77	802
andrewbonney	0:18dd877d2c77	803	/* Double retransmission time-out unless we are trying to
andrewbonney	0:18dd877d2c77	804	* connect to somebody (i.e., we are in SYN_SENT). */
andrewbonney	0:18dd877d2c77	805	if (pcb->state != SYN_SENT) {
andrewbonney	0:18dd877d2c77	806	pcb->rto = ((pcb->sa >> 3) + pcb->sv) << tcp_backoff[pcb->nrtx];
andrewbonney	0:18dd877d2c77	807	}
andrewbonney	0:18dd877d2c77	808
andrewbonney	0:18dd877d2c77	809	/* Reset the retransmission timer. */
andrewbonney	0:18dd877d2c77	810	pcb->rtime = 0;
andrewbonney	0:18dd877d2c77	811
andrewbonney	0:18dd877d2c77	812	/* Reduce congestion window and ssthresh. */
andrewbonney	0:18dd877d2c77	813	eff_wnd = LWIP_MIN(pcb->cwnd, pcb->snd_wnd);
andrewbonney	0:18dd877d2c77	814	pcb->ssthresh = eff_wnd >> 1;
andrewbonney	0:18dd877d2c77	815	if (pcb->ssthresh < (pcb->mss << 1)) {
andrewbonney	0:18dd877d2c77	816	pcb->ssthresh = (pcb->mss << 1);
andrewbonney	0:18dd877d2c77	817	}
andrewbonney	0:18dd877d2c77	818	pcb->cwnd = pcb->mss;
andrewbonney	0:18dd877d2c77	819	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: cwnd %"U16_F
andrewbonney	0:18dd877d2c77	820	" ssthresh %"U16_F"\n",
andrewbonney	0:18dd877d2c77	821	pcb->cwnd, pcb->ssthresh));
andrewbonney	0:18dd877d2c77	822
andrewbonney	0:18dd877d2c77	823	/* The following needs to be called AFTER cwnd is set to one
andrewbonney	0:18dd877d2c77	824	mss - STJ */
andrewbonney	0:18dd877d2c77	825	tcp_rexmit_rto(pcb);
andrewbonney	0:18dd877d2c77	826	}
andrewbonney	0:18dd877d2c77	827	}
andrewbonney	0:18dd877d2c77	828	}
andrewbonney	0:18dd877d2c77	829	/* Check if this PCB has stayed too long in FIN-WAIT-2 */
andrewbonney	0:18dd877d2c77	830	if (pcb->state == FIN_WAIT_2) {
andrewbonney	0:18dd877d2c77	831	if ((u32_t)(tcp_ticks - pcb->tmr) >
andrewbonney	0:18dd877d2c77	832	TCP_FIN_WAIT_TIMEOUT / TCP_SLOW_INTERVAL) {
andrewbonney	0:18dd877d2c77	833	++pcb_remove;
andrewbonney	0:18dd877d2c77	834	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in FIN-WAIT-2\n"));
andrewbonney	0:18dd877d2c77	835	}
andrewbonney	0:18dd877d2c77	836	}
andrewbonney	0:18dd877d2c77	837
andrewbonney	0:18dd877d2c77	838	/* Check if KEEPALIVE should be sent */
andrewbonney	0:18dd877d2c77	839	if((pcb->so_options & SOF_KEEPALIVE) &&
andrewbonney	0:18dd877d2c77	840	((pcb->state == ESTABLISHED) \|\|
andrewbonney	0:18dd877d2c77	841	(pcb->state == CLOSE_WAIT))) {
andrewbonney	0:18dd877d2c77	842	#if LWIP_TCP_KEEPALIVE
andrewbonney	0:18dd877d2c77	843	if((u32_t)(tcp_ticks - pcb->tmr) >
andrewbonney	0:18dd877d2c77	844	(pcb->keep_idle + (pcb->keep_cnt*pcb->keep_intvl))
andrewbonney	0:18dd877d2c77	845	/ TCP_SLOW_INTERVAL)
andrewbonney	0:18dd877d2c77	846	#else
andrewbonney	0:18dd877d2c77	847	if((u32_t)(tcp_ticks - pcb->tmr) >
andrewbonney	0:18dd877d2c77	848	(pcb->keep_idle + TCP_MAXIDLE) / TCP_SLOW_INTERVAL)
andrewbonney	0:18dd877d2c77	849	#endif /* LWIP_TCP_KEEPALIVE */
andrewbonney	0:18dd877d2c77	850	{
andrewbonney	0:18dd877d2c77	851	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: KEEPALIVE timeout. Aborting connection to %"U16_F".%"U16_F".%"U16_F".%"U16_F".\n",
andrewbonney	0:18dd877d2c77	852	ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
andrewbonney	0:18dd877d2c77	853	ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
andrewbonney	0:18dd877d2c77	854
andrewbonney	0:18dd877d2c77	855	++pcb_remove;
andrewbonney	0:18dd877d2c77	856	++pcb_reset;
andrewbonney	0:18dd877d2c77	857	}
andrewbonney	0:18dd877d2c77	858	#if LWIP_TCP_KEEPALIVE
andrewbonney	0:18dd877d2c77	859	else if((u32_t)(tcp_ticks - pcb->tmr) >
andrewbonney	0:18dd877d2c77	860	(pcb->keep_idle + pcb->keep_cnt_sent * pcb->keep_intvl)
andrewbonney	0:18dd877d2c77	861	/ TCP_SLOW_INTERVAL)
andrewbonney	0:18dd877d2c77	862	#else
andrewbonney	0:18dd877d2c77	863	else if((u32_t)(tcp_ticks - pcb->tmr) >
andrewbonney	0:18dd877d2c77	864	(pcb->keep_idle + pcb->keep_cnt_sent * TCP_KEEPINTVL_DEFAULT)
andrewbonney	0:18dd877d2c77	865	/ TCP_SLOW_INTERVAL)
andrewbonney	0:18dd877d2c77	866	#endif /* LWIP_TCP_KEEPALIVE */
andrewbonney	0:18dd877d2c77	867	{
andrewbonney	0:18dd877d2c77	868	tcp_keepalive(pcb);
andrewbonney	0:18dd877d2c77	869	pcb->keep_cnt_sent++;
andrewbonney	0:18dd877d2c77	870	}
andrewbonney	0:18dd877d2c77	871	}
andrewbonney	0:18dd877d2c77	872
andrewbonney	0:18dd877d2c77	873	/* If this PCB has queued out of sequence data, but has been
andrewbonney	0:18dd877d2c77	874	inactive for too long, will drop the data (it will eventually
andrewbonney	0:18dd877d2c77	875	be retransmitted). */
andrewbonney	0:18dd877d2c77	876	#if TCP_QUEUE_OOSEQ
andrewbonney	0:18dd877d2c77	877	if (pcb->ooseq != NULL &&
andrewbonney	0:18dd877d2c77	878	(u32_t)tcp_ticks - pcb->tmr >= pcb->rto * TCP_OOSEQ_TIMEOUT) {
andrewbonney	0:18dd877d2c77	879	tcp_segs_free(pcb->ooseq);
andrewbonney	0:18dd877d2c77	880	pcb->ooseq = NULL;
andrewbonney	0:18dd877d2c77	881	LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: dropping OOSEQ queued data\n"));
andrewbonney	0:18dd877d2c77	882	}
andrewbonney	0:18dd877d2c77	883	#endif /* TCP_QUEUE_OOSEQ */
andrewbonney	0:18dd877d2c77	884
andrewbonney	0:18dd877d2c77	885	/* Check if this PCB has stayed too long in SYN-RCVD */
andrewbonney	0:18dd877d2c77	886	if (pcb->state == SYN_RCVD) {
andrewbonney	0:18dd877d2c77	887	if ((u32_t)(tcp_ticks - pcb->tmr) >
andrewbonney	0:18dd877d2c77	888	TCP_SYN_RCVD_TIMEOUT / TCP_SLOW_INTERVAL) {
andrewbonney	0:18dd877d2c77	889	++pcb_remove;
andrewbonney	0:18dd877d2c77	890	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in SYN-RCVD\n"));
andrewbonney	0:18dd877d2c77	891	}
andrewbonney	0:18dd877d2c77	892	}
andrewbonney	0:18dd877d2c77	893
andrewbonney	0:18dd877d2c77	894	/* Check if this PCB has stayed too long in LAST-ACK */
andrewbonney	0:18dd877d2c77	895	if (pcb->state == LAST_ACK) {
andrewbonney	0:18dd877d2c77	896	if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
andrewbonney	0:18dd877d2c77	897	++pcb_remove;
andrewbonney	0:18dd877d2c77	898	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in LAST-ACK\n"));
andrewbonney	0:18dd877d2c77	899	}
andrewbonney	0:18dd877d2c77	900	}
andrewbonney	0:18dd877d2c77	901
andrewbonney	0:18dd877d2c77	902	/* If the PCB should be removed, do it. */
andrewbonney	0:18dd877d2c77	903	if (pcb_remove) {
andrewbonney	0:18dd877d2c77	904	tcp_pcb_purge(pcb);
andrewbonney	0:18dd877d2c77	905	/* Remove PCB from tcp_active_pcbs list. */
andrewbonney	0:18dd877d2c77	906	if (prev != NULL) {
andrewbonney	0:18dd877d2c77	907	LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_active_pcbs", pcb != tcp_active_pcbs);
andrewbonney	0:18dd877d2c77	908	prev->next = pcb->next;
andrewbonney	0:18dd877d2c77	909	} else {
andrewbonney	0:18dd877d2c77	910	/* This PCB was the first. */
andrewbonney	0:18dd877d2c77	911	LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_active_pcbs", tcp_active_pcbs == pcb);
andrewbonney	0:18dd877d2c77	912	tcp_active_pcbs = pcb->next;
andrewbonney	0:18dd877d2c77	913	}
andrewbonney	0:18dd877d2c77	914
andrewbonney	0:18dd877d2c77	915	TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_ABRT);
andrewbonney	0:18dd877d2c77	916	if (pcb_reset) {
andrewbonney	0:18dd877d2c77	917	tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
andrewbonney	0:18dd877d2c77	918	pcb->local_port, pcb->remote_port);
andrewbonney	0:18dd877d2c77	919	}
andrewbonney	0:18dd877d2c77	920
andrewbonney	0:18dd877d2c77	921	pcb2 = pcb->next;
andrewbonney	0:18dd877d2c77	922	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	923	pcb = pcb2;
andrewbonney	0:18dd877d2c77	924	} else {
andrewbonney	0:18dd877d2c77	925	/* get the 'next' element now and work with 'prev' below (in case of abort) */
andrewbonney	0:18dd877d2c77	926	prev = pcb;
andrewbonney	0:18dd877d2c77	927	pcb = pcb->next;
andrewbonney	0:18dd877d2c77	928
andrewbonney	0:18dd877d2c77	929	/* We check if we should poll the connection. */
andrewbonney	0:18dd877d2c77	930	++prev->polltmr;
andrewbonney	0:18dd877d2c77	931	if (prev->polltmr >= prev->pollinterval) {
andrewbonney	0:18dd877d2c77	932	prev->polltmr = 0;
andrewbonney	0:18dd877d2c77	933	LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: polling application\n"));
andrewbonney	0:18dd877d2c77	934	TCP_EVENT_POLL(prev, err);
andrewbonney	0:18dd877d2c77	935	/* if err == ERR_ABRT, 'prev' is already deallocated */
andrewbonney	0:18dd877d2c77	936	if (err == ERR_OK) {
andrewbonney	0:18dd877d2c77	937	tcp_output(prev);
andrewbonney	0:18dd877d2c77	938	}
andrewbonney	0:18dd877d2c77	939	}
andrewbonney	0:18dd877d2c77	940	}
andrewbonney	0:18dd877d2c77	941	}
andrewbonney	0:18dd877d2c77	942
andrewbonney	0:18dd877d2c77	943
andrewbonney	0:18dd877d2c77	944	/* Steps through all of the TIME-WAIT PCBs. */
andrewbonney	0:18dd877d2c77	945	prev = NULL;
andrewbonney	0:18dd877d2c77	946	pcb = tcp_tw_pcbs;
andrewbonney	0:18dd877d2c77	947	while (pcb != NULL) {
andrewbonney	0:18dd877d2c77	948	LWIP_ASSERT("tcp_slowtmr: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
andrewbonney	0:18dd877d2c77	949	pcb_remove = 0;
andrewbonney	0:18dd877d2c77	950
andrewbonney	0:18dd877d2c77	951	/* Check if this PCB has stayed long enough in TIME-WAIT */
andrewbonney	0:18dd877d2c77	952	if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
andrewbonney	0:18dd877d2c77	953	++pcb_remove;
andrewbonney	0:18dd877d2c77	954	}
andrewbonney	0:18dd877d2c77	955
andrewbonney	0:18dd877d2c77	956
andrewbonney	0:18dd877d2c77	957
andrewbonney	0:18dd877d2c77	958	/* If the PCB should be removed, do it. */
andrewbonney	0:18dd877d2c77	959	if (pcb_remove) {
andrewbonney	0:18dd877d2c77	960	tcp_pcb_purge(pcb);
andrewbonney	0:18dd877d2c77	961	/* Remove PCB from tcp_tw_pcbs list. */
andrewbonney	0:18dd877d2c77	962	if (prev != NULL) {
andrewbonney	0:18dd877d2c77	963	LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_tw_pcbs", pcb != tcp_tw_pcbs);
andrewbonney	0:18dd877d2c77	964	prev->next = pcb->next;
andrewbonney	0:18dd877d2c77	965	} else {
andrewbonney	0:18dd877d2c77	966	/* This PCB was the first. */
andrewbonney	0:18dd877d2c77	967	LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_tw_pcbs", tcp_tw_pcbs == pcb);
andrewbonney	0:18dd877d2c77	968	tcp_tw_pcbs = pcb->next;
andrewbonney	0:18dd877d2c77	969	}
andrewbonney	0:18dd877d2c77	970	pcb2 = pcb->next;
andrewbonney	0:18dd877d2c77	971	memp_free(MEMP_TCP_PCB, pcb);
andrewbonney	0:18dd877d2c77	972	pcb = pcb2;
andrewbonney	0:18dd877d2c77	973	} else {
andrewbonney	0:18dd877d2c77	974	prev = pcb;
andrewbonney	0:18dd877d2c77	975	pcb = pcb->next;
andrewbonney	0:18dd877d2c77	976	}
andrewbonney	0:18dd877d2c77	977	}
andrewbonney	0:18dd877d2c77	978	}
andrewbonney	0:18dd877d2c77	979
andrewbonney	0:18dd877d2c77	980	/**
andrewbonney	0:18dd877d2c77	981	* Is called every TCP_FAST_INTERVAL (250 ms) and process data previously
andrewbonney	0:18dd877d2c77	982	* "refused" by upper layer (application) and sends delayed ACKs.
andrewbonney	0:18dd877d2c77	983	*
andrewbonney	0:18dd877d2c77	984	* Automatically called from tcp_tmr().
andrewbonney	0:18dd877d2c77	985	*/
andrewbonney	0:18dd877d2c77	986	void
andrewbonney	0:18dd877d2c77	987	tcp_fasttmr(void)
andrewbonney	0:18dd877d2c77	988	{
andrewbonney	0:18dd877d2c77	989	struct tcp_pcb *pcb = tcp_active_pcbs;
andrewbonney	0:18dd877d2c77	990
andrewbonney	0:18dd877d2c77	991	while(pcb != NULL) {
andrewbonney	0:18dd877d2c77	992	struct tcp_pcb *next = pcb->next;
andrewbonney	0:18dd877d2c77	993	/* If there is data which was previously "refused" by upper layer */
andrewbonney	0:18dd877d2c77	994	if (pcb->refused_data != NULL) {
andrewbonney	0:18dd877d2c77	995	/* Notify again application with data previously received. */
andrewbonney	0:18dd877d2c77	996	err_t err;
andrewbonney	0:18dd877d2c77	997	LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_fasttmr: notify kept packet\n"));
andrewbonney	0:18dd877d2c77	998	TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
andrewbonney	0:18dd877d2c77	999	if (err == ERR_OK) {
andrewbonney	0:18dd877d2c77	1000	pcb->refused_data = NULL;
andrewbonney	0:18dd877d2c77	1001	} else if (err == ERR_ABRT) {
andrewbonney	0:18dd877d2c77	1002	/* if err == ERR_ABRT, 'pcb' is already deallocated */
andrewbonney	0:18dd877d2c77	1003	pcb = NULL;
andrewbonney	0:18dd877d2c77	1004	}
andrewbonney	0:18dd877d2c77	1005	}
andrewbonney	0:18dd877d2c77	1006
andrewbonney	0:18dd877d2c77	1007	/* send delayed ACKs */
andrewbonney	0:18dd877d2c77	1008	if (pcb && (pcb->flags & TF_ACK_DELAY)) {
andrewbonney	0:18dd877d2c77	1009	LWIP_DEBUGF(TCP_DEBUG, ("tcp_fasttmr: delayed ACK\n"));
andrewbonney	0:18dd877d2c77	1010	tcp_ack_now(pcb);
andrewbonney	0:18dd877d2c77	1011	tcp_output(pcb);
andrewbonney	0:18dd877d2c77	1012	pcb->flags &= ~(TF_ACK_DELAY \| TF_ACK_NOW);
andrewbonney	0:18dd877d2c77	1013	}
andrewbonney	0:18dd877d2c77	1014
andrewbonney	0:18dd877d2c77	1015	pcb = next;
andrewbonney	0:18dd877d2c77	1016	}
andrewbonney	0:18dd877d2c77	1017	}
andrewbonney	0:18dd877d2c77	1018
andrewbonney	0:18dd877d2c77	1019	/**
andrewbonney	0:18dd877d2c77	1020	* Deallocates a list of TCP segments (tcp_seg structures).
andrewbonney	0:18dd877d2c77	1021	*
andrewbonney	0:18dd877d2c77	1022	* @param seg tcp_seg list of TCP segments to free
andrewbonney	0:18dd877d2c77	1023	*/
andrewbonney	0:18dd877d2c77	1024	void
andrewbonney	0:18dd877d2c77	1025	tcp_segs_free(struct tcp_seg *seg)
andrewbonney	0:18dd877d2c77	1026	{
andrewbonney	0:18dd877d2c77	1027	while (seg != NULL) {
andrewbonney	0:18dd877d2c77	1028	struct tcp_seg *next = seg->next;
andrewbonney	0:18dd877d2c77	1029	tcp_seg_free(seg);
andrewbonney	0:18dd877d2c77	1030	seg = next;
andrewbonney	0:18dd877d2c77	1031	}
andrewbonney	0:18dd877d2c77	1032	}
andrewbonney	0:18dd877d2c77	1033
andrewbonney	0:18dd877d2c77	1034	/**
andrewbonney	0:18dd877d2c77	1035	* Frees a TCP segment (tcp_seg structure).
andrewbonney	0:18dd877d2c77	1036	*
andrewbonney	0:18dd877d2c77	1037	* @param seg single tcp_seg to free
andrewbonney	0:18dd877d2c77	1038	*/
andrewbonney	0:18dd877d2c77	1039	void
andrewbonney	0:18dd877d2c77	1040	tcp_seg_free(struct tcp_seg *seg)
andrewbonney	0:18dd877d2c77	1041	{
andrewbonney	0:18dd877d2c77	1042	if (seg != NULL) {
andrewbonney	0:18dd877d2c77	1043	if (seg->p != NULL) {
andrewbonney	0:18dd877d2c77	1044	pbuf_free(seg->p);
andrewbonney	0:18dd877d2c77	1045	#if TCP_DEBUG
andrewbonney	0:18dd877d2c77	1046	seg->p = NULL;
andrewbonney	0:18dd877d2c77	1047	#endif /* TCP_DEBUG */
andrewbonney	0:18dd877d2c77	1048	}
andrewbonney	0:18dd877d2c77	1049	memp_free(MEMP_TCP_SEG, seg);
andrewbonney	0:18dd877d2c77	1050	}
andrewbonney	0:18dd877d2c77	1051	}
andrewbonney	0:18dd877d2c77	1052
andrewbonney	0:18dd877d2c77	1053	/**
andrewbonney	0:18dd877d2c77	1054	* Sets the priority of a connection.
andrewbonney	0:18dd877d2c77	1055	*
andrewbonney	0:18dd877d2c77	1056	* @param pcb the tcp_pcb to manipulate
andrewbonney	0:18dd877d2c77	1057	* @param prio new priority
andrewbonney	0:18dd877d2c77	1058	*/
andrewbonney	0:18dd877d2c77	1059	void
andrewbonney	0:18dd877d2c77	1060	tcp_setprio(struct tcp_pcb *pcb, u8_t prio)
andrewbonney	0:18dd877d2c77	1061	{
andrewbonney	0:18dd877d2c77	1062	pcb->prio = prio;
andrewbonney	0:18dd877d2c77	1063	}
andrewbonney	0:18dd877d2c77	1064
andrewbonney	0:18dd877d2c77	1065	#if TCP_QUEUE_OOSEQ
andrewbonney	0:18dd877d2c77	1066	/**
andrewbonney	0:18dd877d2c77	1067	* Returns a copy of the given TCP segment.
andrewbonney	0:18dd877d2c77	1068	* The pbuf and data are not copied, only the pointers
andrewbonney	0:18dd877d2c77	1069	*
andrewbonney	0:18dd877d2c77	1070	* @param seg the old tcp_seg
andrewbonney	0:18dd877d2c77	1071	* @return a copy of seg
andrewbonney	0:18dd877d2c77	1072	*/
andrewbonney	0:18dd877d2c77	1073	struct tcp_seg *
andrewbonney	0:18dd877d2c77	1074	tcp_seg_copy(struct tcp_seg *seg)
andrewbonney	0:18dd877d2c77	1075	{
andrewbonney	0:18dd877d2c77	1076	struct tcp_seg *cseg;
andrewbonney	0:18dd877d2c77	1077
andrewbonney	0:18dd877d2c77	1078	cseg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG);
andrewbonney	0:18dd877d2c77	1079	if (cseg == NULL) {
andrewbonney	0:18dd877d2c77	1080	return NULL;
andrewbonney	0:18dd877d2c77	1081	}
andrewbonney	0:18dd877d2c77	1082	SMEMCPY((u8_t )cseg, (const u8_t )seg, sizeof(struct tcp_seg));
andrewbonney	0:18dd877d2c77	1083	pbuf_ref(cseg->p);
andrewbonney	0:18dd877d2c77	1084	return cseg;
andrewbonney	0:18dd877d2c77	1085	}
andrewbonney	0:18dd877d2c77	1086	#endif /* TCP_QUEUE_OOSEQ */
andrewbonney	0:18dd877d2c77	1087
andrewbonney	0:18dd877d2c77	1088	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	1089	/**
andrewbonney	0:18dd877d2c77	1090	* Default receive callback that is called if the user didn't register
andrewbonney	0:18dd877d2c77	1091	* a recv callback for the pcb.
andrewbonney	0:18dd877d2c77	1092	*/
andrewbonney	0:18dd877d2c77	1093	err_t
andrewbonney	0:18dd877d2c77	1094	tcp_recv_null(void arg, struct tcp_pcb pcb, struct pbuf *p, err_t err)
andrewbonney	0:18dd877d2c77	1095	{
andrewbonney	0:18dd877d2c77	1096	LWIP_UNUSED_ARG(arg);
andrewbonney	0:18dd877d2c77	1097	if (p != NULL) {
andrewbonney	0:18dd877d2c77	1098	tcp_recved(pcb, p->tot_len);
andrewbonney	0:18dd877d2c77	1099	pbuf_free(p);
andrewbonney	0:18dd877d2c77	1100	} else if (err == ERR_OK) {
andrewbonney	0:18dd877d2c77	1101	return tcp_close(pcb);
andrewbonney	0:18dd877d2c77	1102	}
andrewbonney	0:18dd877d2c77	1103	return ERR_OK;
andrewbonney	0:18dd877d2c77	1104	}
andrewbonney	0:18dd877d2c77	1105	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	1106
andrewbonney	0:18dd877d2c77	1107	/**
andrewbonney	0:18dd877d2c77	1108	* Kills the oldest active connection that has lower priority than prio.
andrewbonney	0:18dd877d2c77	1109	*
andrewbonney	0:18dd877d2c77	1110	* @param prio minimum priority
andrewbonney	0:18dd877d2c77	1111	*/
andrewbonney	0:18dd877d2c77	1112	static void
andrewbonney	0:18dd877d2c77	1113	tcp_kill_prio(u8_t prio)
andrewbonney	0:18dd877d2c77	1114	{
andrewbonney	0:18dd877d2c77	1115	struct tcp_pcb pcb, inactive;
andrewbonney	0:18dd877d2c77	1116	u32_t inactivity;
andrewbonney	0:18dd877d2c77	1117	u8_t mprio;
andrewbonney	0:18dd877d2c77	1118
andrewbonney	0:18dd877d2c77	1119
andrewbonney	0:18dd877d2c77	1120	mprio = TCP_PRIO_MAX;
andrewbonney	0:18dd877d2c77	1121
andrewbonney	0:18dd877d2c77	1122	/* We kill the oldest active connection that has lower priority than prio. */
andrewbonney	0:18dd877d2c77	1123	inactivity = 0;
andrewbonney	0:18dd877d2c77	1124	inactive = NULL;
andrewbonney	0:18dd877d2c77	1125	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1126	if (pcb->prio <= prio &&
andrewbonney	0:18dd877d2c77	1127	pcb->prio <= mprio &&
andrewbonney	0:18dd877d2c77	1128	(u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
andrewbonney	0:18dd877d2c77	1129	inactivity = tcp_ticks - pcb->tmr;
andrewbonney	0:18dd877d2c77	1130	inactive = pcb;
andrewbonney	0:18dd877d2c77	1131	mprio = pcb->prio;
andrewbonney	0:18dd877d2c77	1132	}
andrewbonney	0:18dd877d2c77	1133	}
andrewbonney	0:18dd877d2c77	1134	if (inactive != NULL) {
andrewbonney	0:18dd877d2c77	1135	LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_prio: killing oldest PCB %p (%"S32_F")\n",
andrewbonney	0:18dd877d2c77	1136	(void *)inactive, inactivity));
andrewbonney	0:18dd877d2c77	1137	tcp_abort(inactive);
andrewbonney	0:18dd877d2c77	1138	}
andrewbonney	0:18dd877d2c77	1139	}
andrewbonney	0:18dd877d2c77	1140
andrewbonney	0:18dd877d2c77	1141	/**
andrewbonney	0:18dd877d2c77	1142	* Kills the oldest connection that is in TIME_WAIT state.
andrewbonney	0:18dd877d2c77	1143	* Called from tcp_alloc() if no more connections are available.
andrewbonney	0:18dd877d2c77	1144	*/
andrewbonney	0:18dd877d2c77	1145	static void
andrewbonney	0:18dd877d2c77	1146	tcp_kill_timewait(void)
andrewbonney	0:18dd877d2c77	1147	{
andrewbonney	0:18dd877d2c77	1148	struct tcp_pcb pcb, inactive;
andrewbonney	0:18dd877d2c77	1149	u32_t inactivity;
andrewbonney	0:18dd877d2c77	1150
andrewbonney	0:18dd877d2c77	1151	inactivity = 0;
andrewbonney	0:18dd877d2c77	1152	inactive = NULL;
andrewbonney	0:18dd877d2c77	1153	/* Go through the list of TIME_WAIT pcbs and get the oldest pcb. */
andrewbonney	0:18dd877d2c77	1154	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1155	if ((u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
andrewbonney	0:18dd877d2c77	1156	inactivity = tcp_ticks - pcb->tmr;
andrewbonney	0:18dd877d2c77	1157	inactive = pcb;
andrewbonney	0:18dd877d2c77	1158	}
andrewbonney	0:18dd877d2c77	1159	}
andrewbonney	0:18dd877d2c77	1160	if (inactive != NULL) {
andrewbonney	0:18dd877d2c77	1161	LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_timewait: killing oldest TIME-WAIT PCB %p (%"S32_F")\n",
andrewbonney	0:18dd877d2c77	1162	(void *)inactive, inactivity));
andrewbonney	0:18dd877d2c77	1163	tcp_abort(inactive);
andrewbonney	0:18dd877d2c77	1164	}
andrewbonney	0:18dd877d2c77	1165	}
andrewbonney	0:18dd877d2c77	1166
andrewbonney	0:18dd877d2c77	1167	/**
andrewbonney	0:18dd877d2c77	1168	* Allocate a new tcp_pcb structure.
andrewbonney	0:18dd877d2c77	1169	*
andrewbonney	0:18dd877d2c77	1170	* @param prio priority for the new pcb
andrewbonney	0:18dd877d2c77	1171	* @return a new tcp_pcb that initially is in state CLOSED
andrewbonney	0:18dd877d2c77	1172	*/
andrewbonney	0:18dd877d2c77	1173	struct tcp_pcb *
andrewbonney	0:18dd877d2c77	1174	tcp_alloc(u8_t prio)
andrewbonney	0:18dd877d2c77	1175	{
andrewbonney	0:18dd877d2c77	1176	struct tcp_pcb *pcb;
andrewbonney	0:18dd877d2c77	1177	u32_t iss;
andrewbonney	0:18dd877d2c77	1178
andrewbonney	0:18dd877d2c77	1179	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
andrewbonney	0:18dd877d2c77	1180	if (pcb == NULL) {
andrewbonney	0:18dd877d2c77	1181	/* Try killing oldest connection in TIME-WAIT. */
andrewbonney	0:18dd877d2c77	1182	LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing off oldest TIME-WAIT connection\n"));
andrewbonney	0:18dd877d2c77	1183	tcp_kill_timewait();
andrewbonney	0:18dd877d2c77	1184	/* Try to allocate a tcp_pcb again. */
andrewbonney	0:18dd877d2c77	1185	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
andrewbonney	0:18dd877d2c77	1186	if (pcb == NULL) {
andrewbonney	0:18dd877d2c77	1187	/* Try killing active connections with lower priority than the new one. */
andrewbonney	0:18dd877d2c77	1188	LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing connection with prio lower than %d\n", prio));
andrewbonney	0:18dd877d2c77	1189	tcp_kill_prio(prio);
andrewbonney	0:18dd877d2c77	1190	/* Try to allocate a tcp_pcb again. */
andrewbonney	0:18dd877d2c77	1191	pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
andrewbonney	0:18dd877d2c77	1192	if (pcb != NULL) {
andrewbonney	0:18dd877d2c77	1193	/* adjust err stats: memp_malloc failed twice before */
andrewbonney	0:18dd877d2c77	1194	MEMP_STATS_DEC(err, MEMP_TCP_PCB);
andrewbonney	0:18dd877d2c77	1195	}
andrewbonney	0:18dd877d2c77	1196	}
andrewbonney	0:18dd877d2c77	1197	if (pcb != NULL) {
andrewbonney	0:18dd877d2c77	1198	/* adjust err stats: timewait PCB was freed above */
andrewbonney	0:18dd877d2c77	1199	MEMP_STATS_DEC(err, MEMP_TCP_PCB);
andrewbonney	0:18dd877d2c77	1200	}
andrewbonney	0:18dd877d2c77	1201	}
andrewbonney	0:18dd877d2c77	1202	if (pcb != NULL) {
andrewbonney	0:18dd877d2c77	1203	memset(pcb, 0, sizeof(struct tcp_pcb));
andrewbonney	0:18dd877d2c77	1204	pcb->prio = prio;
andrewbonney	0:18dd877d2c77	1205	pcb->snd_buf = TCP_SND_BUF;
andrewbonney	0:18dd877d2c77	1206	pcb->snd_queuelen = 0;
andrewbonney	0:18dd877d2c77	1207	pcb->rcv_wnd = TCP_WND;
andrewbonney	0:18dd877d2c77	1208	pcb->rcv_ann_wnd = TCP_WND;
andrewbonney	0:18dd877d2c77	1209	pcb->tos = 0;
andrewbonney	0:18dd877d2c77	1210	pcb->ttl = TCP_TTL;
andrewbonney	0:18dd877d2c77	1211	/* As initial send MSS, we use TCP_MSS but limit it to 536.
andrewbonney	0:18dd877d2c77	1212	The send MSS is updated when an MSS option is received. */
andrewbonney	0:18dd877d2c77	1213	pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
andrewbonney	0:18dd877d2c77	1214	pcb->rto = 3000 / TCP_SLOW_INTERVAL;
andrewbonney	0:18dd877d2c77	1215	pcb->sa = 0;
andrewbonney	0:18dd877d2c77	1216	pcb->sv = 3000 / TCP_SLOW_INTERVAL;
andrewbonney	0:18dd877d2c77	1217	pcb->rtime = -1;
andrewbonney	0:18dd877d2c77	1218	pcb->cwnd = 1;
andrewbonney	0:18dd877d2c77	1219	iss = tcp_next_iss();
andrewbonney	0:18dd877d2c77	1220	pcb->snd_wl2 = iss;
andrewbonney	0:18dd877d2c77	1221	pcb->snd_nxt = iss;
andrewbonney	0:18dd877d2c77	1222	pcb->lastack = iss;
andrewbonney	0:18dd877d2c77	1223	pcb->snd_lbb = iss;
andrewbonney	0:18dd877d2c77	1224	pcb->tmr = tcp_ticks;
andrewbonney	0:18dd877d2c77	1225
andrewbonney	0:18dd877d2c77	1226	LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: tcp_ticks=%"U32_F" iss=%"U32_F"\n", tcp_ticks, iss));
andrewbonney	0:18dd877d2c77	1227
andrewbonney	0:18dd877d2c77	1228	pcb->polltmr = 0;
andrewbonney	0:18dd877d2c77	1229
andrewbonney	0:18dd877d2c77	1230	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	1231	pcb->recv = tcp_recv_null;
andrewbonney	0:18dd877d2c77	1232	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	1233
andrewbonney	0:18dd877d2c77	1234	/* Init KEEPALIVE timer */
andrewbonney	0:18dd877d2c77	1235	pcb->keep_idle = TCP_KEEPIDLE_DEFAULT;
andrewbonney	0:18dd877d2c77	1236
andrewbonney	0:18dd877d2c77	1237	#if LWIP_TCP_KEEPALIVE
andrewbonney	0:18dd877d2c77	1238	pcb->keep_intvl = TCP_KEEPINTVL_DEFAULT;
andrewbonney	0:18dd877d2c77	1239	pcb->keep_cnt = TCP_KEEPCNT_DEFAULT;
andrewbonney	0:18dd877d2c77	1240	#endif /* LWIP_TCP_KEEPALIVE */
andrewbonney	0:18dd877d2c77	1241
andrewbonney	0:18dd877d2c77	1242	pcb->keep_cnt_sent = 0;
andrewbonney	0:18dd877d2c77	1243	}
andrewbonney	0:18dd877d2c77	1244	return pcb;
andrewbonney	0:18dd877d2c77	1245	}
andrewbonney	0:18dd877d2c77	1246
andrewbonney	0:18dd877d2c77	1247	/**
andrewbonney	0:18dd877d2c77	1248	* Creates a new TCP protocol control block but doesn't place it on
andrewbonney	0:18dd877d2c77	1249	* any of the TCP PCB lists.
andrewbonney	0:18dd877d2c77	1250	* The pcb is not put on any list until binding using tcp_bind().
andrewbonney	0:18dd877d2c77	1251	*
andrewbonney	0:18dd877d2c77	1252	* @internal: Maybe there should be a idle TCP PCB list where these
andrewbonney	0:18dd877d2c77	1253	* PCBs are put on. Port reservation using tcp_bind() is implemented but
andrewbonney	0:18dd877d2c77	1254	* allocated pcbs that are not bound can't be killed automatically if wanting
andrewbonney	0:18dd877d2c77	1255	* to allocate a pcb with higher prio (@see tcp_kill_prio())
andrewbonney	0:18dd877d2c77	1256	*
andrewbonney	0:18dd877d2c77	1257	* @return a new tcp_pcb that initially is in state CLOSED
andrewbonney	0:18dd877d2c77	1258	*/
andrewbonney	0:18dd877d2c77	1259	struct tcp_pcb *
andrewbonney	0:18dd877d2c77	1260	tcp_new(void)
andrewbonney	0:18dd877d2c77	1261	{
andrewbonney	0:18dd877d2c77	1262	return tcp_alloc(TCP_PRIO_NORMAL);
andrewbonney	0:18dd877d2c77	1263	}
andrewbonney	0:18dd877d2c77	1264
andrewbonney	0:18dd877d2c77	1265	/**
andrewbonney	0:18dd877d2c77	1266	* Used to specify the argument that should be passed callback
andrewbonney	0:18dd877d2c77	1267	* functions.
andrewbonney	0:18dd877d2c77	1268	*
andrewbonney	0:18dd877d2c77	1269	* @param pcb tcp_pcb to set the callback argument
andrewbonney	0:18dd877d2c77	1270	* @param arg void pointer argument to pass to callback functions
andrewbonney	0:18dd877d2c77	1271	*/
andrewbonney	0:18dd877d2c77	1272	void
andrewbonney	0:18dd877d2c77	1273	tcp_arg(struct tcp_pcb pcb, void arg)
andrewbonney	0:18dd877d2c77	1274	{
andrewbonney	0:18dd877d2c77	1275	pcb->callback_arg = arg;
andrewbonney	0:18dd877d2c77	1276	}
andrewbonney	0:18dd877d2c77	1277	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	1278
andrewbonney	0:18dd877d2c77	1279	/**
andrewbonney	0:18dd877d2c77	1280	* Used to specify the function that should be called when a TCP
andrewbonney	0:18dd877d2c77	1281	* connection receives data.
andrewbonney	0:18dd877d2c77	1282	*
andrewbonney	0:18dd877d2c77	1283	* @param pcb tcp_pcb to set the recv callback
andrewbonney	0:18dd877d2c77	1284	* @param recv callback function to call for this pcb when data is received
andrewbonney	0:18dd877d2c77	1285	*/
andrewbonney	0:18dd877d2c77	1286	void
andrewbonney	0:18dd877d2c77	1287	tcp_recv(struct tcp_pcb *pcb, tcp_recv_fn recv)
andrewbonney	0:18dd877d2c77	1288	{
andrewbonney	0:18dd877d2c77	1289	pcb->recv = recv;
andrewbonney	0:18dd877d2c77	1290	}
andrewbonney	0:18dd877d2c77	1291
andrewbonney	0:18dd877d2c77	1292	/**
andrewbonney	0:18dd877d2c77	1293	* Used to specify the function that should be called when TCP data
andrewbonney	0:18dd877d2c77	1294	* has been successfully delivered to the remote host.
andrewbonney	0:18dd877d2c77	1295	*
andrewbonney	0:18dd877d2c77	1296	* @param pcb tcp_pcb to set the sent callback
andrewbonney	0:18dd877d2c77	1297	* @param sent callback function to call for this pcb when data is successfully sent
andrewbonney	0:18dd877d2c77	1298	*/
andrewbonney	0:18dd877d2c77	1299	void
andrewbonney	0:18dd877d2c77	1300	tcp_sent(struct tcp_pcb *pcb, tcp_sent_fn sent)
andrewbonney	0:18dd877d2c77	1301	{
andrewbonney	0:18dd877d2c77	1302	pcb->sent = sent;
andrewbonney	0:18dd877d2c77	1303	}
andrewbonney	0:18dd877d2c77	1304
andrewbonney	0:18dd877d2c77	1305	/**
andrewbonney	0:18dd877d2c77	1306	* Used to specify the function that should be called when a fatal error
andrewbonney	0:18dd877d2c77	1307	* has occured on the connection.
andrewbonney	0:18dd877d2c77	1308	*
andrewbonney	0:18dd877d2c77	1309	* @param pcb tcp_pcb to set the err callback
andrewbonney	0:18dd877d2c77	1310	* @param err callback function to call for this pcb when a fatal error
andrewbonney	0:18dd877d2c77	1311	* has occured on the connection
andrewbonney	0:18dd877d2c77	1312	*/
andrewbonney	0:18dd877d2c77	1313	void
andrewbonney	0:18dd877d2c77	1314	tcp_err(struct tcp_pcb *pcb, tcp_err_fn err)
andrewbonney	0:18dd877d2c77	1315	{
andrewbonney	0:18dd877d2c77	1316	pcb->errf = err;
andrewbonney	0:18dd877d2c77	1317	}
andrewbonney	0:18dd877d2c77	1318
andrewbonney	0:18dd877d2c77	1319	/**
andrewbonney	0:18dd877d2c77	1320	* Used for specifying the function that should be called when a
andrewbonney	0:18dd877d2c77	1321	* LISTENing connection has been connected to another host.
andrewbonney	0:18dd877d2c77	1322	*
andrewbonney	0:18dd877d2c77	1323	* @param pcb tcp_pcb to set the accept callback
andrewbonney	0:18dd877d2c77	1324	* @param accept callback function to call for this pcb when LISTENing
andrewbonney	0:18dd877d2c77	1325	* connection has been connected to another host
andrewbonney	0:18dd877d2c77	1326	*/
andrewbonney	0:18dd877d2c77	1327	void
andrewbonney	0:18dd877d2c77	1328	tcp_accept(struct tcp_pcb *pcb, tcp_accept_fn accept)
andrewbonney	0:18dd877d2c77	1329	{
andrewbonney	0:18dd877d2c77	1330	pcb->accept = accept;
andrewbonney	0:18dd877d2c77	1331	}
andrewbonney	0:18dd877d2c77	1332	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	1333
andrewbonney	0:18dd877d2c77	1334
andrewbonney	0:18dd877d2c77	1335	/**
andrewbonney	0:18dd877d2c77	1336	* Used to specify the function that should be called periodically
andrewbonney	0:18dd877d2c77	1337	* from TCP. The interval is specified in terms of the TCP coarse
andrewbonney	0:18dd877d2c77	1338	* timer interval, which is called twice a second.
andrewbonney	0:18dd877d2c77	1339	*
andrewbonney	0:18dd877d2c77	1340	*/
andrewbonney	0:18dd877d2c77	1341	void
andrewbonney	0:18dd877d2c77	1342	tcp_poll(struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval)
andrewbonney	0:18dd877d2c77	1343	{
andrewbonney	0:18dd877d2c77	1344	#if LWIP_CALLBACK_API
andrewbonney	0:18dd877d2c77	1345	pcb->poll = poll;
andrewbonney	0:18dd877d2c77	1346	#else /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	1347	LWIP_UNUSED_ARG(poll);
andrewbonney	0:18dd877d2c77	1348	#endif /* LWIP_CALLBACK_API */
andrewbonney	0:18dd877d2c77	1349	pcb->pollinterval = interval;
andrewbonney	0:18dd877d2c77	1350	}
andrewbonney	0:18dd877d2c77	1351
andrewbonney	0:18dd877d2c77	1352	/**
andrewbonney	0:18dd877d2c77	1353	* Purges a TCP PCB. Removes any buffered data and frees the buffer memory
andrewbonney	0:18dd877d2c77	1354	* (pcb->ooseq, pcb->unsent and pcb->unacked are freed).
andrewbonney	0:18dd877d2c77	1355	*
andrewbonney	0:18dd877d2c77	1356	* @param pcb tcp_pcb to purge. The pcb itself is not deallocated!
andrewbonney	0:18dd877d2c77	1357	*/
andrewbonney	0:18dd877d2c77	1358	void
andrewbonney	0:18dd877d2c77	1359	tcp_pcb_purge(struct tcp_pcb *pcb)
andrewbonney	0:18dd877d2c77	1360	{
andrewbonney	0:18dd877d2c77	1361	if (pcb->state != CLOSED &&
andrewbonney	0:18dd877d2c77	1362	pcb->state != TIME_WAIT &&
andrewbonney	0:18dd877d2c77	1363	pcb->state != LISTEN) {
andrewbonney	0:18dd877d2c77	1364
andrewbonney	0:18dd877d2c77	1365	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge\n"));
andrewbonney	0:18dd877d2c77	1366
andrewbonney	0:18dd877d2c77	1367	#if TCP_LISTEN_BACKLOG
andrewbonney	0:18dd877d2c77	1368	if (pcb->state == SYN_RCVD) {
andrewbonney	0:18dd877d2c77	1369	/* Need to find the corresponding listen_pcb and decrease its accepts_pending */
andrewbonney	0:18dd877d2c77	1370	struct tcp_pcb_listen *lpcb;
andrewbonney	0:18dd877d2c77	1371	LWIP_ASSERT("tcp_pcb_purge: pcb->state == SYN_RCVD but tcp_listen_pcbs is NULL",
andrewbonney	0:18dd877d2c77	1372	tcp_listen_pcbs.listen_pcbs != NULL);
andrewbonney	0:18dd877d2c77	1373	for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
andrewbonney	0:18dd877d2c77	1374	if ((lpcb->local_port == pcb->local_port) &&
andrewbonney	0:18dd877d2c77	1375	(ip_addr_isany(&lpcb->local_ip) \|\|
andrewbonney	0:18dd877d2c77	1376	ip_addr_cmp(&pcb->local_ip, &lpcb->local_ip))) {
andrewbonney	0:18dd877d2c77	1377	/* port and address of the listen pcb match the timed-out pcb */
andrewbonney	0:18dd877d2c77	1378	LWIP_ASSERT("tcp_pcb_purge: listen pcb does not have accepts pending",
andrewbonney	0:18dd877d2c77	1379	lpcb->accepts_pending > 0);
andrewbonney	0:18dd877d2c77	1380	lpcb->accepts_pending--;
andrewbonney	0:18dd877d2c77	1381	break;
andrewbonney	0:18dd877d2c77	1382	}
andrewbonney	0:18dd877d2c77	1383	}
andrewbonney	0:18dd877d2c77	1384	}
andrewbonney	0:18dd877d2c77	1385	#endif /* TCP_LISTEN_BACKLOG */
andrewbonney	0:18dd877d2c77	1386
andrewbonney	0:18dd877d2c77	1387
andrewbonney	0:18dd877d2c77	1388	if (pcb->refused_data != NULL) {
andrewbonney	0:18dd877d2c77	1389	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->refused_data\n"));
andrewbonney	0:18dd877d2c77	1390	pbuf_free(pcb->refused_data);
andrewbonney	0:18dd877d2c77	1391	pcb->refused_data = NULL;
andrewbonney	0:18dd877d2c77	1392	}
andrewbonney	0:18dd877d2c77	1393	if (pcb->unsent != NULL) {
andrewbonney	0:18dd877d2c77	1394	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: not all data sent\n"));
andrewbonney	0:18dd877d2c77	1395	}
andrewbonney	0:18dd877d2c77	1396	if (pcb->unacked != NULL) {
andrewbonney	0:18dd877d2c77	1397	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->unacked\n"));
andrewbonney	0:18dd877d2c77	1398	}
andrewbonney	0:18dd877d2c77	1399	#if TCP_QUEUE_OOSEQ
andrewbonney	0:18dd877d2c77	1400	if (pcb->ooseq != NULL) {
andrewbonney	0:18dd877d2c77	1401	LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->ooseq\n"));
andrewbonney	0:18dd877d2c77	1402	}
andrewbonney	0:18dd877d2c77	1403	tcp_segs_free(pcb->ooseq);
andrewbonney	0:18dd877d2c77	1404	pcb->ooseq = NULL;
andrewbonney	0:18dd877d2c77	1405	#endif /* TCP_QUEUE_OOSEQ */
andrewbonney	0:18dd877d2c77	1406
andrewbonney	0:18dd877d2c77	1407	/* Stop the retransmission timer as it will expect data on unacked
andrewbonney	0:18dd877d2c77	1408	queue if it fires */
andrewbonney	0:18dd877d2c77	1409	pcb->rtime = -1;
andrewbonney	0:18dd877d2c77	1410
andrewbonney	0:18dd877d2c77	1411	tcp_segs_free(pcb->unsent);
andrewbonney	0:18dd877d2c77	1412	tcp_segs_free(pcb->unacked);
andrewbonney	0:18dd877d2c77	1413	pcb->unacked = pcb->unsent = NULL;
andrewbonney	0:18dd877d2c77	1414	#if TCP_OVERSIZE
andrewbonney	0:18dd877d2c77	1415	pcb->unsent_oversize = 0;
andrewbonney	0:18dd877d2c77	1416	#endif /* TCP_OVERSIZE */
andrewbonney	0:18dd877d2c77	1417	}
andrewbonney	0:18dd877d2c77	1418	}
andrewbonney	0:18dd877d2c77	1419
andrewbonney	0:18dd877d2c77	1420	/**
andrewbonney	0:18dd877d2c77	1421	* Purges the PCB and removes it from a PCB list. Any delayed ACKs are sent first.
andrewbonney	0:18dd877d2c77	1422	*
andrewbonney	0:18dd877d2c77	1423	* @param pcblist PCB list to purge.
andrewbonney	0:18dd877d2c77	1424	* @param pcb tcp_pcb to purge. The pcb itself is NOT deallocated!
andrewbonney	0:18dd877d2c77	1425	*/
andrewbonney	0:18dd877d2c77	1426	void
andrewbonney	0:18dd877d2c77	1427	tcp_pcb_remove(struct tcp_pcb *pcblist, struct tcp_pcb pcb)
andrewbonney	0:18dd877d2c77	1428	{
andrewbonney	0:18dd877d2c77	1429	TCP_RMV(pcblist, pcb);
andrewbonney	0:18dd877d2c77	1430
andrewbonney	0:18dd877d2c77	1431	tcp_pcb_purge(pcb);
andrewbonney	0:18dd877d2c77	1432
andrewbonney	0:18dd877d2c77	1433	/* if there is an outstanding delayed ACKs, send it */
andrewbonney	0:18dd877d2c77	1434	if (pcb->state != TIME_WAIT &&
andrewbonney	0:18dd877d2c77	1435	pcb->state != LISTEN &&
andrewbonney	0:18dd877d2c77	1436	pcb->flags & TF_ACK_DELAY) {
andrewbonney	0:18dd877d2c77	1437	pcb->flags \|= TF_ACK_NOW;
andrewbonney	0:18dd877d2c77	1438	tcp_output(pcb);
andrewbonney	0:18dd877d2c77	1439	}
andrewbonney	0:18dd877d2c77	1440
andrewbonney	0:18dd877d2c77	1441	if (pcb->state != LISTEN) {
andrewbonney	0:18dd877d2c77	1442	LWIP_ASSERT("unsent segments leaking", pcb->unsent == NULL);
andrewbonney	0:18dd877d2c77	1443	LWIP_ASSERT("unacked segments leaking", pcb->unacked == NULL);
andrewbonney	0:18dd877d2c77	1444	#if TCP_QUEUE_OOSEQ
andrewbonney	0:18dd877d2c77	1445	LWIP_ASSERT("ooseq segments leaking", pcb->ooseq == NULL);
andrewbonney	0:18dd877d2c77	1446	#endif /* TCP_QUEUE_OOSEQ */
andrewbonney	0:18dd877d2c77	1447	}
andrewbonney	0:18dd877d2c77	1448
andrewbonney	0:18dd877d2c77	1449	pcb->state = CLOSED;
andrewbonney	0:18dd877d2c77	1450
andrewbonney	0:18dd877d2c77	1451	LWIP_ASSERT("tcp_pcb_remove: tcp_pcbs_sane()", tcp_pcbs_sane());
andrewbonney	0:18dd877d2c77	1452	}
andrewbonney	0:18dd877d2c77	1453
andrewbonney	0:18dd877d2c77	1454	/**
andrewbonney	0:18dd877d2c77	1455	* Calculates a new initial sequence number for new connections.
andrewbonney	0:18dd877d2c77	1456	*
andrewbonney	0:18dd877d2c77	1457	* @return u32_t pseudo random sequence number
andrewbonney	0:18dd877d2c77	1458	*/
andrewbonney	0:18dd877d2c77	1459	u32_t
andrewbonney	0:18dd877d2c77	1460	tcp_next_iss(void)
andrewbonney	0:18dd877d2c77	1461	{
andrewbonney	0:18dd877d2c77	1462	static u32_t iss = 6510;
andrewbonney	0:18dd877d2c77	1463
andrewbonney	0:18dd877d2c77	1464	iss += tcp_ticks; /* XXX */
andrewbonney	0:18dd877d2c77	1465	return iss;
andrewbonney	0:18dd877d2c77	1466	}
andrewbonney	0:18dd877d2c77	1467
andrewbonney	0:18dd877d2c77	1468	#if TCP_CALCULATE_EFF_SEND_MSS
andrewbonney	0:18dd877d2c77	1469	/**
andrewbonney	0:18dd877d2c77	1470	* Calcluates the effective send mss that can be used for a specific IP address
andrewbonney	0:18dd877d2c77	1471	* by using ip_route to determin the netif used to send to the address and
andrewbonney	0:18dd877d2c77	1472	* calculating the minimum of TCP_MSS and that netif's mtu (if set).
andrewbonney	0:18dd877d2c77	1473	*/
andrewbonney	0:18dd877d2c77	1474	u16_t
andrewbonney	0:18dd877d2c77	1475	tcp_eff_send_mss(u16_t sendmss, ip_addr_t *addr)
andrewbonney	0:18dd877d2c77	1476	{
andrewbonney	0:18dd877d2c77	1477	u16_t mss_s;
andrewbonney	0:18dd877d2c77	1478	struct netif *outif;
andrewbonney	0:18dd877d2c77	1479
andrewbonney	0:18dd877d2c77	1480	outif = ip_route(addr);
andrewbonney	0:18dd877d2c77	1481	if ((outif != NULL) && (outif->mtu != 0)) {
andrewbonney	0:18dd877d2c77	1482	mss_s = outif->mtu - IP_HLEN - TCP_HLEN;
andrewbonney	0:18dd877d2c77	1483	/* RFC 1122, chap 4.2.2.6:
andrewbonney	0:18dd877d2c77	1484	* Eff.snd.MSS = min(SendMSS+20, MMS_S) - TCPhdrsize - IPoptionsize
andrewbonney	0:18dd877d2c77	1485	* We correct for TCP options in tcp_write(), and don't support IP options.
andrewbonney	0:18dd877d2c77	1486	*/
andrewbonney	0:18dd877d2c77	1487	sendmss = LWIP_MIN(sendmss, mss_s);
andrewbonney	0:18dd877d2c77	1488	}
andrewbonney	0:18dd877d2c77	1489	return sendmss;
andrewbonney	0:18dd877d2c77	1490	}
andrewbonney	0:18dd877d2c77	1491	#endif /* TCP_CALCULATE_EFF_SEND_MSS */
andrewbonney	0:18dd877d2c77	1492
andrewbonney	0:18dd877d2c77	1493	const char*
andrewbonney	0:18dd877d2c77	1494	tcp_debug_state_str(enum tcp_state s)
andrewbonney	0:18dd877d2c77	1495	{
andrewbonney	0:18dd877d2c77	1496	return tcp_state_str[s];
andrewbonney	0:18dd877d2c77	1497	}
andrewbonney	0:18dd877d2c77	1498
andrewbonney	0:18dd877d2c77	1499	#if TCP_DEBUG \|\| TCP_INPUT_DEBUG \|\| TCP_OUTPUT_DEBUG
andrewbonney	0:18dd877d2c77	1500	/**
andrewbonney	0:18dd877d2c77	1501	* Print a tcp header for debugging purposes.
andrewbonney	0:18dd877d2c77	1502	*
andrewbonney	0:18dd877d2c77	1503	* @param tcphdr pointer to a struct tcp_hdr
andrewbonney	0:18dd877d2c77	1504	*/
andrewbonney	0:18dd877d2c77	1505	void
andrewbonney	0:18dd877d2c77	1506	tcp_debug_print(struct tcp_hdr *tcphdr)
andrewbonney	0:18dd877d2c77	1507	{
andrewbonney	0:18dd877d2c77	1508	LWIP_DEBUGF(TCP_DEBUG, ("TCP header:\n"));
andrewbonney	0:18dd877d2c77	1509	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
andrewbonney	0:18dd877d2c77	1510	LWIP_DEBUGF(TCP_DEBUG, ("\| %5"U16_F" \| %5"U16_F" \| (src port, dest port)\n",
andrewbonney	0:18dd877d2c77	1511	ntohs(tcphdr->src), ntohs(tcphdr->dest)));
andrewbonney	0:18dd877d2c77	1512	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
andrewbonney	0:18dd877d2c77	1513	LWIP_DEBUGF(TCP_DEBUG, ("\| %010"U32_F" \| (seq no)\n",
andrewbonney	0:18dd877d2c77	1514	ntohl(tcphdr->seqno)));
andrewbonney	0:18dd877d2c77	1515	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
andrewbonney	0:18dd877d2c77	1516	LWIP_DEBUGF(TCP_DEBUG, ("\| %010"U32_F" \| (ack no)\n",
andrewbonney	0:18dd877d2c77	1517	ntohl(tcphdr->ackno)));
andrewbonney	0:18dd877d2c77	1518	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
andrewbonney	0:18dd877d2c77	1519	LWIP_DEBUGF(TCP_DEBUG, ("\| %2"U16_F" \| \|%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"\| %5"U16_F" \| (hdrlen, flags (",
andrewbonney	0:18dd877d2c77	1520	TCPH_HDRLEN(tcphdr),
andrewbonney	0:18dd877d2c77	1521	TCPH_FLAGS(tcphdr) >> 5 & 1,
andrewbonney	0:18dd877d2c77	1522	TCPH_FLAGS(tcphdr) >> 4 & 1,
andrewbonney	0:18dd877d2c77	1523	TCPH_FLAGS(tcphdr) >> 3 & 1,
andrewbonney	0:18dd877d2c77	1524	TCPH_FLAGS(tcphdr) >> 2 & 1,
andrewbonney	0:18dd877d2c77	1525	TCPH_FLAGS(tcphdr) >> 1 & 1,
andrewbonney	0:18dd877d2c77	1526	TCPH_FLAGS(tcphdr) & 1,
andrewbonney	0:18dd877d2c77	1527	ntohs(tcphdr->wnd)));
andrewbonney	0:18dd877d2c77	1528	tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
andrewbonney	0:18dd877d2c77	1529	LWIP_DEBUGF(TCP_DEBUG, ("), win)\n"));
andrewbonney	0:18dd877d2c77	1530	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
andrewbonney	0:18dd877d2c77	1531	LWIP_DEBUGF(TCP_DEBUG, ("\| 0x%04"X16_F" \| %5"U16_F" \| (chksum, urgp)\n",
andrewbonney	0:18dd877d2c77	1532	ntohs(tcphdr->chksum), ntohs(tcphdr->urgp)));
andrewbonney	0:18dd877d2c77	1533	LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
andrewbonney	0:18dd877d2c77	1534	}
andrewbonney	0:18dd877d2c77	1535
andrewbonney	0:18dd877d2c77	1536	/**
andrewbonney	0:18dd877d2c77	1537	* Print a tcp state for debugging purposes.
andrewbonney	0:18dd877d2c77	1538	*
andrewbonney	0:18dd877d2c77	1539	* @param s enum tcp_state to print
andrewbonney	0:18dd877d2c77	1540	*/
andrewbonney	0:18dd877d2c77	1541	void
andrewbonney	0:18dd877d2c77	1542	tcp_debug_print_state(enum tcp_state s)
andrewbonney	0:18dd877d2c77	1543	{
andrewbonney	0:18dd877d2c77	1544	LWIP_DEBUGF(TCP_DEBUG, ("State: %s\n", tcp_state_str[s]));
andrewbonney	0:18dd877d2c77	1545	}
andrewbonney	0:18dd877d2c77	1546
andrewbonney	0:18dd877d2c77	1547	/**
andrewbonney	0:18dd877d2c77	1548	* Print tcp flags for debugging purposes.
andrewbonney	0:18dd877d2c77	1549	*
andrewbonney	0:18dd877d2c77	1550	* @param flags tcp flags, all active flags are printed
andrewbonney	0:18dd877d2c77	1551	*/
andrewbonney	0:18dd877d2c77	1552	void
andrewbonney	0:18dd877d2c77	1553	tcp_debug_print_flags(u8_t flags)
andrewbonney	0:18dd877d2c77	1554	{
andrewbonney	0:18dd877d2c77	1555	if (flags & TCP_FIN) {
andrewbonney	0:18dd877d2c77	1556	LWIP_DEBUGF(TCP_DEBUG, ("FIN "));
andrewbonney	0:18dd877d2c77	1557	}
andrewbonney	0:18dd877d2c77	1558	if (flags & TCP_SYN) {
andrewbonney	0:18dd877d2c77	1559	LWIP_DEBUGF(TCP_DEBUG, ("SYN "));
andrewbonney	0:18dd877d2c77	1560	}
andrewbonney	0:18dd877d2c77	1561	if (flags & TCP_RST) {
andrewbonney	0:18dd877d2c77	1562	LWIP_DEBUGF(TCP_DEBUG, ("RST "));
andrewbonney	0:18dd877d2c77	1563	}
andrewbonney	0:18dd877d2c77	1564	if (flags & TCP_PSH) {
andrewbonney	0:18dd877d2c77	1565	LWIP_DEBUGF(TCP_DEBUG, ("PSH "));
andrewbonney	0:18dd877d2c77	1566	}
andrewbonney	0:18dd877d2c77	1567	if (flags & TCP_ACK) {
andrewbonney	0:18dd877d2c77	1568	LWIP_DEBUGF(TCP_DEBUG, ("ACK "));
andrewbonney	0:18dd877d2c77	1569	}
andrewbonney	0:18dd877d2c77	1570	if (flags & TCP_URG) {
andrewbonney	0:18dd877d2c77	1571	LWIP_DEBUGF(TCP_DEBUG, ("URG "));
andrewbonney	0:18dd877d2c77	1572	}
andrewbonney	0:18dd877d2c77	1573	if (flags & TCP_ECE) {
andrewbonney	0:18dd877d2c77	1574	LWIP_DEBUGF(TCP_DEBUG, ("ECE "));
andrewbonney	0:18dd877d2c77	1575	}
andrewbonney	0:18dd877d2c77	1576	if (flags & TCP_CWR) {
andrewbonney	0:18dd877d2c77	1577	LWIP_DEBUGF(TCP_DEBUG, ("CWR "));
andrewbonney	0:18dd877d2c77	1578	}
andrewbonney	0:18dd877d2c77	1579	LWIP_DEBUGF(TCP_DEBUG, ("\n"));
andrewbonney	0:18dd877d2c77	1580	}
andrewbonney	0:18dd877d2c77	1581
andrewbonney	0:18dd877d2c77	1582	/**
andrewbonney	0:18dd877d2c77	1583	* Print all tcp_pcbs in every list for debugging purposes.
andrewbonney	0:18dd877d2c77	1584	*/
andrewbonney	0:18dd877d2c77	1585	void
andrewbonney	0:18dd877d2c77	1586	tcp_debug_print_pcbs(void)
andrewbonney	0:18dd877d2c77	1587	{
andrewbonney	0:18dd877d2c77	1588	struct tcp_pcb *pcb;
andrewbonney	0:18dd877d2c77	1589	LWIP_DEBUGF(TCP_DEBUG, ("Active PCB states:\n"));
andrewbonney	0:18dd877d2c77	1590	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1591	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
andrewbonney	0:18dd877d2c77	1592	pcb->local_port, pcb->remote_port,
andrewbonney	0:18dd877d2c77	1593	pcb->snd_nxt, pcb->rcv_nxt));
andrewbonney	0:18dd877d2c77	1594	tcp_debug_print_state(pcb->state);
andrewbonney	0:18dd877d2c77	1595	}
andrewbonney	0:18dd877d2c77	1596	LWIP_DEBUGF(TCP_DEBUG, ("Listen PCB states:\n"));
andrewbonney	0:18dd877d2c77	1597	for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1598	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
andrewbonney	0:18dd877d2c77	1599	pcb->local_port, pcb->remote_port,
andrewbonney	0:18dd877d2c77	1600	pcb->snd_nxt, pcb->rcv_nxt));
andrewbonney	0:18dd877d2c77	1601	tcp_debug_print_state(pcb->state);
andrewbonney	0:18dd877d2c77	1602	}
andrewbonney	0:18dd877d2c77	1603	LWIP_DEBUGF(TCP_DEBUG, ("TIME-WAIT PCB states:\n"));
andrewbonney	0:18dd877d2c77	1604	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1605	LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
andrewbonney	0:18dd877d2c77	1606	pcb->local_port, pcb->remote_port,
andrewbonney	0:18dd877d2c77	1607	pcb->snd_nxt, pcb->rcv_nxt));
andrewbonney	0:18dd877d2c77	1608	tcp_debug_print_state(pcb->state);
andrewbonney	0:18dd877d2c77	1609	}
andrewbonney	0:18dd877d2c77	1610	}
andrewbonney	0:18dd877d2c77	1611
andrewbonney	0:18dd877d2c77	1612	/**
andrewbonney	0:18dd877d2c77	1613	* Check state consistency of the tcp_pcb lists.
andrewbonney	0:18dd877d2c77	1614	*/
andrewbonney	0:18dd877d2c77	1615	s16_t
andrewbonney	0:18dd877d2c77	1616	tcp_pcbs_sane(void)
andrewbonney	0:18dd877d2c77	1617	{
andrewbonney	0:18dd877d2c77	1618	struct tcp_pcb *pcb;
andrewbonney	0:18dd877d2c77	1619	for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1620	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != CLOSED", pcb->state != CLOSED);
andrewbonney	0:18dd877d2c77	1621	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != LISTEN", pcb->state != LISTEN);
andrewbonney	0:18dd877d2c77	1622	LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
andrewbonney	0:18dd877d2c77	1623	}
andrewbonney	0:18dd877d2c77	1624	for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
andrewbonney	0:18dd877d2c77	1625	LWIP_ASSERT("tcp_pcbs_sane: tw pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
andrewbonney	0:18dd877d2c77	1626	}
andrewbonney	0:18dd877d2c77	1627	return 1;
andrewbonney	0:18dd877d2c77	1628	}
andrewbonney	0:18dd877d2c77	1629	#endif /* TCP_DEBUG */
andrewbonney	0:18dd877d2c77	1630
andrewbonney	0:18dd877d2c77	1631	#endif /* LWIP_TCP */

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Type:	Library
Created:	26 May 2011
Imports:	33
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	0
Followers:	1

lwip/core/tcp.c@0:18dd877d2c77, 2011-05-26 (annotated)

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