1664 lines
53 KiB
C
1664 lines
53 KiB
C
/**
|
||
* @file
|
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* Transmission Control Protocol for IP
|
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*
|
||
* This file contains common functions for the TCP implementation, such as functinos
|
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* for manipulating the data structures and the TCP timer functions. TCP functions
|
||
* related to input and output is found in tcp_in.c and tcp_out.c respectively.
|
||
*
|
||
*/
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||
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/*
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* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification,
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* are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice,
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* this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
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* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
|
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* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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* OF SUCH DAMAGE.
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*
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* This file is part of the lwIP TCP/IP stack.
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*
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* Author: Adam Dunkels <adam@sics.se>
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*
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*/
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#include "lwip/opt.h"
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#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
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#include "lwip/def.h"
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#include "lwip/mem.h"
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#include "lwip/memp.h"
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#include "lwip/snmp.h"
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#include "lwip/tcp.h"
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#include "lwip/tcp_impl.h"
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#include "lwip/debug.h"
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#include "lwip/stats.h"
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#include <string.h>
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#if TCP_DEBUG
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const char tcp_state_str_rodata[][12] ICACHE_RODATA_ATTR = {
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"CLOSED",
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"LISTEN",
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"SYN_SENT",
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"SYN_RCVD",
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"ESTABLISHED",
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"FIN_WAIT_1",
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"FIN_WAIT_2",
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"CLOSE_WAIT",
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"CLOSING",
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"LAST_ACK",
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"TIME_WAIT"
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};
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char tcp_state_str[12];
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#endif
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/* Incremented every coarse grained timer shot (typically every 500 ms). */
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u32_t tcp_ticks;
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const u8_t tcp_backoff[13] ICACHE_RODATA_ATTR =
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{ 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7};
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/* Times per slowtmr hits */
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const u8_t tcp_persist_backoff[7] ICACHE_RODATA_ATTR = { 3, 6, 12, 24, 48, 96, 120 };
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/* The TCP PCB lists. */
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/** List of all TCP PCBs bound but not yet (connected || listening) */
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struct tcp_pcb *tcp_bound_pcbs;
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/** List of all TCP PCBs in LISTEN state */
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union tcp_listen_pcbs_t tcp_listen_pcbs;
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/** List of all TCP PCBs that are in a state in which
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* they accept or send data. */
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struct tcp_pcb *tcp_active_pcbs;
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/** List of all TCP PCBs in TIME-WAIT state */
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struct tcp_pcb *tcp_tw_pcbs;
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#define NUM_TCP_PCB_LISTS 4
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#define NUM_TCP_PCB_LISTS_NO_TIME_WAIT 3
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/** An array with all (non-temporary) PCB lists, mainly used for smaller code size */
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struct tcp_pcb ** const tcp_pcb_lists[] ICACHE_RODATA_ATTR = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
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&tcp_active_pcbs, &tcp_tw_pcbs};
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/** Only used for temporary storage. */
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struct tcp_pcb *tcp_tmp_pcb;
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/** Timer counter to handle calling slow-timer from tcp_tmr() */
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static u8_t tcp_timer;
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static u16_t tcp_new_port(void);//<2F><><EFBFBD><EFBFBD>µ<EFBFBD>tcp<63><70><EFBFBD>ض˿<D8B6>
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/**
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* Called periodically to dispatch TCP timers.
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*
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*/
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void
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tcp_tmr(void)
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{
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/* Call tcp_fasttmr() every 250 ms */
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tcp_fasttmr();
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if (++tcp_timer & 1) {
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/* Call tcp_tmr() every 500 ms, i.e., every other timer
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tcp_tmr() is called. */
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tcp_slowtmr();
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}
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}
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/**
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* Closes the TX side of a connection held by the PCB.
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* For tcp_close(), a RST is sent if the application didn't receive all data
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* (tcp_recved() not called for all data passed to recv callback).
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*
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* Listening pcbs are freed and may not be referenced any more.
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* Connection pcbs are freed if not yet connected and may not be referenced
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* any more. If a connection is established (at least SYN received or in
|
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* a closing state), the connection is closed, and put in a closing state.
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* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
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* unsafe to reference it.
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*
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* @param pcb the tcp_pcb to close
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* @return ERR_OK if connection has been closed
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* another err_t if closing failed and pcb is not freed
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*/
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static err_t
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tcp_close_shutdown(struct tcp_pcb *pcb, u8_t rst_on_unacked_data)
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{
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err_t err;
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if (rst_on_unacked_data && (pcb->state != LISTEN)) {
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if ((pcb->refused_data != NULL) || (pcb->rcv_wnd != TCP_WND)) {
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/* Not all data received by application, send RST to tell the remote
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side about this. */
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LWIP_ASSERT("pcb->flags & TF_RXCLOSED", pcb->flags & TF_RXCLOSED);
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/* don't call tcp_abort here: we must not deallocate the pcb since
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that might not be expected when calling tcp_close */
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tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
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pcb->local_port, pcb->remote_port);
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tcp_pcb_purge(pcb);
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/* TODO: to which state do we move now? */
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/* move to TIME_WAIT since we close actively */
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TCP_RMV(&tcp_active_pcbs, pcb);
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pcb->state = TIME_WAIT;
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TCP_REG(&tcp_tw_pcbs, pcb);
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return ERR_OK;
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}
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}
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switch (pcb->state) {
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case CLOSED:
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/* Closing a pcb in the CLOSED state might seem erroneous,
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* however, it is in this state once allocated and as yet unused
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* and the user needs some way to free it should the need arise.
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* Calling tcp_close() with a pcb that has already been closed, (i.e. twice)
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* or for a pcb that has been used and then entered the CLOSED state
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* is erroneous, but this should never happen as the pcb has in those cases
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* been freed, and so any remaining handles are bogus. */
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/*<2A><>CLOSED״̬<D7B4>¹ر<C2B9>һ<EFBFBD><D2BB>pcb<63>ƺ<EFBFBD><C6BA>Ǵ<EFBFBD><C7B4><EFBFBD>ģ<EFBFBD>
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*<2A><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ˣ<EFBFBD>һ<EFBFBD><D2BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>״̬<D7B4>·<EFBFBD><C2B7><EFBFBD><EFBFBD>˶<EFBFBD><CBB6>һ<EFBFBD>û<EFBFBD><C3BB>ʹ<EFBFBD><CAB9>,<2C>û<EFBFBD><C3BB><EFBFBD>ҪһЩ<D2BB>취<EFBFBD><ECB7A8><EFBFBD>ͷ<EFBFBD><CDB7><EFBFBD>
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*<2A><><EFBFBD><EFBFBD>һ<EFBFBD><D2BB><EFBFBD>Ѿ<EFBFBD><D1BE><EFBFBD><EFBFBD>رյ<D8B1>pcb<63><62>tcp_close(),(<28><>2<EFBFBD><32>)<29><><EFBFBD><EFBFBD>һ<EFBFBD><D2BB><EFBFBD>Ѿ<EFBFBD><D1BE><EFBFBD>ʹ<EFBFBD><CAB9><EFBFBD><EFBFBD>֮<EFBFBD><EFBFBD><F3A3ACBD><EFBFBD>CLOSE״̬<D7B4>Ǵ<EFBFBD><C7B4><EFBFBD><EFBFBD>
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*<2A><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Щ<EFBFBD><D0A9><EFBFBD><EFBFBD>±<EFBFBD><C2B1>ͷŵ<CDB7>pcb<63>Dz<EFBFBD><C7B2><EFBFBD><EFBFBD><EFBFBD>ڵ<EFBFBD>,<2C><>ˣ<EFBFBD><CBA3>κ<EFBFBD>ʣ<EFBFBD><CAA3>ľ<EFBFBD><C4BE><EFBFBD>Ǽٵ<C7BC>
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*/
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err = ERR_OK;//<2F>趨<EFBFBD><E8B6A8><EFBFBD><EFBFBD>ֵ
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if (pcb->local_port != 0) {
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TCP_RMV(&tcp_bound_pcbs, pcb);
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}
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memp_free(MEMP_TCP_PCB, pcb);//<2F><>MEMP_TCP_PCB<43>ڴ<EFBFBD><DAB4><EFBFBD>趨<EFBFBD>ͷŵ<CDB7><C5B5><EFBFBD>pcb<63><62>Ӧ<EFBFBD>ĵ<EFBFBD>Ԫֵ,<2C>ͷ<EFBFBD><CDB7>ڴ<EFBFBD>
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pcb = NULL;
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break;
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case LISTEN:
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err = ERR_OK;
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tcp_pcb_remove(&tcp_listen_pcbs.pcbs, pcb);//<2F>Ӽ<EFBFBD><D3BC><EFBFBD><EFBFBD>PCB<43>б<EFBFBD><D0B1><EFBFBD>ɾ<EFBFBD><C9BE><EFBFBD>Ӧ<EFBFBD><D3A6>pcb
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memp_free(MEMP_TCP_PCB_LISTEN, pcb);//<2F><>MEMP_TCP_PCB_LISTEN<45>ڴ<EFBFBD><DAB4><EFBFBD><EFBFBD><EFBFBD>趨<EFBFBD>ͷŵ<CDB7>pcb<63><62>Ԫֵ ,<2C>ͷ<EFBFBD><CDB7>ڴ<EFBFBD>
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pcb = NULL;
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break;
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case SYN_SENT:
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err = ERR_OK;
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tcp_pcb_remove(&tcp_active_pcbs, pcb);
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memp_free(MEMP_TCP_PCB, pcb);
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pcb = NULL;
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snmp_inc_tcpattemptfails();
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break;
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case SYN_RCVD:
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err = tcp_send_fin(pcb);//<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ر<EFBFBD>FIN<49><4E><EFBFBD>ֱ<EFBFBD><D6B1><EFBFBD>
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if (err == ERR_OK) {
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snmp_inc_tcpattemptfails();
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pcb->state = FIN_WAIT_1;//ת<><D7AA>FIN_WAIT_1״̬
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}
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break;
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case ESTABLISHED:
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err = tcp_send_fin(pcb);
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if (err == ERR_OK) {
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snmp_inc_tcpestabresets();
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pcb->state = FIN_WAIT_1;
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}
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break;
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case CLOSE_WAIT:
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err = tcp_send_fin(pcb);
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if (err == ERR_OK) {
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snmp_inc_tcpestabresets();
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pcb->state = LAST_ACK;//<2F><><EFBFBD><EFBFBD>LAST_ACK<43>ȴ<EFBFBD>ACK<43><4B>ʱ
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}
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break;
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default:
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/* Has already been closed, do nothing. */
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err = ERR_OK;
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pcb = NULL;
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break;
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}
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if (pcb != NULL && err == ERR_OK) {
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/* To ensure all data has been sent when tcp_close returns, we have
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to make sure tcp_output doesn't fail.
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Since we don't really have to ensure all data has been sent when tcp_close
|
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returns (unsent data is sent from tcp timer functions, also), we don't care
|
||
for the return value of tcp_output for now. */
|
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/* @todo: When implementing SO_LINGER, this must be changed somehow:
|
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If SOF_LINGER is set, the data should be sent and acked before close returns.
|
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This can only be valid for sequential APIs, not for the raw API. */
|
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tcp_output(pcb);//<2F><><EFBFBD>ú<EFBFBD><C3BA><EFBFBD><EFBFBD>Ϳ<EFBFBD><CDBF>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʣ<EFBFBD><CAA3>ı<EFBFBD><C4B1>ģ<EFBFBD><C4A3><EFBFBD><EFBFBD><EFBFBD>FIN<49><4E><EFBFBD>ֱ<EFBFBD><D6B1>Ķ<EFBFBD>
|
||
}
|
||
return err;
|
||
}
|
||
|
||
/**
|
||
* Closes the connection held by the PCB.
|
||
*
|
||
* Listening pcbs are freed and may not be referenced any more.
|
||
* Connection pcbs are freed if not yet connected and may not be referenced
|
||
* any more. If a connection is established (at least SYN received or in
|
||
* a closing state), the connection is closed, and put in a closing state.
|
||
* The pcb is then automatically freed in tcp_slowtmr(). It is therefore
|
||
* unsafe to reference it (unless an error is returned).
|
||
*
|
||
* @param pcb the tcp_pcb to close
|
||
* @return ERR_OK if connection has been closed
|
||
* another err_t if closing failed and pcb is not freed
|
||
*/
|
||
/*
|
||
*ͨ<><CDA8>PCB<43>ر<EFBFBD><D8B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||
*<2A><><EFBFBD><EFBFBD><EFBFBD>е<EFBFBD>pcbӦ<62>ñ<EFBFBD><C3B1>ͷŵģ<C5B5>Ҳ<EFBFBD><D2B2><EFBFBD><EFBFBD>ԶҲ<D4B6><D2B2><EFBFBD>ᱻʹ<E1B1BB><CAB9><EFBFBD><EFBFBD>
|
||
*<2A><><EFBFBD>û<EFBFBD><C3BB><EFBFBD><EFBFBD><EFBFBD>ӻ<EFBFBD><D3BB><EFBFBD><EFBFBD><EFBFBD>Ҳû<D2B2>б<EFBFBD><D0B1><EFBFBD><EFBFBD><EFBFBD>,<2C><><EFBFBD>ӵ<EFBFBD>pcbӦ<62>ñ<EFBFBD><C3B1>ͷŵ<CDB7>
|
||
*<2A><><EFBFBD>һ<EFBFBD><D2BB><EFBFBD><EFBFBD><EFBFBD>ӱ<EFBFBD><D3B1><EFBFBD><EFBFBD><EFBFBD>(<28><><EFBFBD><EFBFBD>SYN<59>Ѿ<EFBFBD><D1BE><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ջ<EFBFBD><D5BB><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><D2BB><EFBFBD>ر<EFBFBD><D8B1>е<EFBFBD>״̬)
|
||
*<2A><><EFBFBD>ӱ<EFBFBD><D3B1>ر<EFBFBD><D8B1>ˣ<EFBFBD><CBA3><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><D2BB><EFBFBD><EFBFBD><EFBFBD>ڹرյ<D8B1>״̬
|
||
*pcb<63>Զ<EFBFBD><D4B6><EFBFBD>tcp_slowtmr()<29>ͷ<EFBFBD>,<2C><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Dz<EFBFBD><C7B2><EFBFBD>ȫ<EFBFBD><C8AB>
|
||
*/
|
||
err_t
|
||
tcp_close(struct tcp_pcb *pcb)
|
||
{
|
||
#if TCP_DEBUG //TCP debug<75><67>Ϣ<EFBFBD><CFA2><EFBFBD><EFBFBD>ӡpcb<63><62>״̬
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_close: closing in "));
|
||
tcp_debug_print_state(pcb->state);
|
||
#endif /* TCP_DEBUG */
|
||
|
||
if (pcb->state != LISTEN) {
|
||
/* Set a flag not to receive any more data... */
|
||
pcb->flags |= TF_RXCLOSED;
|
||
}
|
||
/* ... and close */
|
||
return tcp_close_shutdown(pcb, 1);
|
||
}
|
||
|
||
/**
|
||
* Causes all or part of a full-duplex connection of this PCB to be shut down.
|
||
* This doesn't deallocate the PCB!
|
||
*
|
||
* @param pcb PCB to shutdown
|
||
* @param shut_rx shut down receive side if this is != 0
|
||
* @param shut_tx shut down send side if this is != 0
|
||
* @return ERR_OK if shutdown succeeded (or the PCB has already been shut down)
|
||
* another err_t on error.
|
||
*/
|
||
err_t
|
||
tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx)
|
||
{
|
||
if (pcb->state == LISTEN) {
|
||
return ERR_CONN;
|
||
}
|
||
if (shut_rx) {
|
||
/* shut down the receive side: free buffered data... */
|
||
if (pcb->refused_data != NULL) {
|
||
pbuf_free(pcb->refused_data);
|
||
pcb->refused_data = NULL;
|
||
}
|
||
/* ... and set a flag not to receive any more data */
|
||
pcb->flags |= TF_RXCLOSED;
|
||
}
|
||
if (shut_tx) {
|
||
/* This can't happen twice since if it succeeds, the pcb's state is changed.
|
||
Only close in these states as the others directly deallocate the PCB */
|
||
switch (pcb->state) {
|
||
case SYN_RCVD:
|
||
case ESTABLISHED:
|
||
case CLOSE_WAIT:
|
||
return tcp_close_shutdown(pcb, 0);
|
||
default:
|
||
/* don't shut down other states */
|
||
break;
|
||
}
|
||
}
|
||
/* @todo: return another err_t if not in correct state or already shut? */
|
||
return ERR_OK;
|
||
}
|
||
|
||
/**
|
||
* Abandons a connection and optionally sends a RST to the remote
|
||
* host. Deletes the local protocol control block. This is done when
|
||
* a connection is killed because of shortage of memory.
|
||
*
|
||
* @param pcb the tcp_pcb to abort
|
||
* @param reset boolean to indicate whether a reset should be sent
|
||
*/
|
||
void
|
||
tcp_abandon(struct tcp_pcb *pcb, int reset)
|
||
{
|
||
u32_t seqno, ackno;
|
||
u16_t remote_port, local_port;
|
||
ip_addr_t remote_ip, local_ip;
|
||
#if LWIP_CALLBACK_API
|
||
tcp_err_fn errf;
|
||
#endif /* LWIP_CALLBACK_API */
|
||
void *errf_arg;
|
||
|
||
/* pcb->state LISTEN not allowed here */
|
||
LWIP_ASSERT("don't call tcp_abort/tcp_abandon for listen-pcbs",
|
||
pcb->state != LISTEN);
|
||
/* Figure out on which TCP PCB list we are, and remove us. If we
|
||
are in an active state, call the receive function associated with
|
||
the PCB with a NULL argument, and send an RST to the remote end. */
|
||
if (pcb->state == TIME_WAIT) {
|
||
tcp_pcb_remove(&tcp_tw_pcbs, pcb);
|
||
memp_free(MEMP_TCP_PCB, pcb);
|
||
} else {
|
||
seqno = pcb->snd_nxt;
|
||
ackno = pcb->rcv_nxt;
|
||
ip_addr_copy(local_ip, pcb->local_ip);
|
||
ip_addr_copy(remote_ip, pcb->remote_ip);
|
||
local_port = pcb->local_port;
|
||
remote_port = pcb->remote_port;
|
||
#if LWIP_CALLBACK_API
|
||
errf = pcb->errf;
|
||
#endif /* LWIP_CALLBACK_API */
|
||
errf_arg = pcb->callback_arg;
|
||
tcp_pcb_remove(&tcp_active_pcbs, pcb);
|
||
if (pcb->unacked != NULL) {
|
||
tcp_segs_free(pcb->unacked);
|
||
}
|
||
if (pcb->unsent != NULL) {
|
||
tcp_segs_free(pcb->unsent);
|
||
}
|
||
#if TCP_QUEUE_OOSEQ
|
||
if (pcb->ooseq != NULL) {
|
||
tcp_segs_free(pcb->ooseq);
|
||
}
|
||
#endif /* TCP_QUEUE_OOSEQ */
|
||
if (reset) {
|
||
LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_abandon: sending RST\n"));
|
||
tcp_rst(seqno, ackno, &local_ip, &remote_ip, local_port, remote_port);
|
||
}
|
||
TCP_EVENT_ERR(errf, errf_arg, ERR_ABRT);
|
||
memp_free(MEMP_TCP_PCB, pcb);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Aborts the connection by sending a RST (reset) segment to the remote
|
||
* host. The pcb is deallocated. This function never fails.
|
||
*
|
||
* ATTENTION: When calling this from one of the TCP callbacks, make
|
||
* sure you always return ERR_ABRT (and never return ERR_ABRT otherwise
|
||
* or you will risk accessing deallocated memory or memory leaks!
|
||
*
|
||
* @param pcb the tcp pcb to abort
|
||
*/
|
||
void
|
||
tcp_abort(struct tcp_pcb *pcb)
|
||
{
|
||
tcp_abandon(pcb, 1);
|
||
}
|
||
|
||
/**
|
||
* Binds the connection to a local portnumber and IP address. If the
|
||
* IP address is not given (i.e., ipaddr == NULL), the IP address of
|
||
* the outgoing network interface is used instead.
|
||
*
|
||
* @param pcb the tcp_pcb to bind (no check is done whether this pcb is
|
||
* already bound!)
|
||
* @param ipaddr the local ip address to bind to (use IP_ADDR_ANY to bind
|
||
* to any local address
|
||
* @param port the local port to bind to
|
||
* @return ERR_USE if the port is already in use
|
||
* ERR_OK if bound
|
||
*/
|
||
err_t
|
||
tcp_bind(struct tcp_pcb *pcb, ip_addr_t *ipaddr, u16_t port)
|
||
{
|
||
int i;
|
||
int max_pcb_list = NUM_TCP_PCB_LISTS;
|
||
struct tcp_pcb *cpcb;
|
||
|
||
LWIP_ERROR("tcp_bind: can only bind in state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
|
||
|
||
#if SO_REUSE
|
||
/* Unless the REUSEADDR flag is set,
|
||
we have to check the pcbs in TIME-WAIT state, also.
|
||
We do not dump TIME_WAIT pcb's; they can still be matched by incoming
|
||
packets using both local and remote IP addresses and ports to distinguish.
|
||
*/
|
||
if ((pcb->so_options & SOF_REUSEADDR) != 0) {
|
||
max_pcb_list = NUM_TCP_PCB_LISTS_NO_TIME_WAIT;
|
||
}
|
||
#endif /* SO_REUSE */
|
||
|
||
if (port == 0) {
|
||
port = tcp_new_port();
|
||
}
|
||
|
||
/* Check if the address already is in use (on all lists) */
|
||
for (i = 0; i < max_pcb_list; i++) {
|
||
for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
|
||
if (cpcb->local_port == port) {
|
||
#if SO_REUSE
|
||
/* Omit checking for the same port if both pcbs have REUSEADDR set.
|
||
For SO_REUSEADDR, the duplicate-check for a 5-tuple is done in
|
||
tcp_connect. */
|
||
if (((pcb->so_options & SOF_REUSEADDR) == 0) ||
|
||
((cpcb->so_options & SOF_REUSEADDR) == 0))
|
||
#endif /* SO_REUSE */
|
||
{
|
||
if (ip_addr_isany(&(cpcb->local_ip)) ||
|
||
ip_addr_isany(ipaddr) ||
|
||
ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
|
||
//os_printf("Address in use\n");
|
||
return ERR_USE;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
if (!ip_addr_isany(ipaddr)) {
|
||
pcb->local_ip = *ipaddr;
|
||
}
|
||
pcb->local_port = port;
|
||
TCP_REG(&tcp_bound_pcbs, pcb);
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_bind: bind to port %"U16_F"\n", port));
|
||
return ERR_OK;
|
||
}
|
||
#if LWIP_CALLBACK_API
|
||
/**
|
||
* Default accept callback if no accept callback is specified by the user.
|
||
*/
|
||
static err_t
|
||
tcp_accept_null(void *arg, struct tcp_pcb *pcb, err_t err)
|
||
{
|
||
LWIP_UNUSED_ARG(arg);
|
||
LWIP_UNUSED_ARG(pcb);
|
||
LWIP_UNUSED_ARG(err);
|
||
|
||
return ERR_ABRT;
|
||
}
|
||
#endif /* LWIP_CALLBACK_API */
|
||
|
||
/**
|
||
* Set the state of the connection to be LISTEN, which means that it
|
||
* is able to accept incoming connections. The protocol control block
|
||
* is reallocated in order to consume less memory. Setting the
|
||
* connection to LISTEN is an irreversible process.
|
||
*<2A><>ij<EFBFBD><C4B3><EFBFBD>Ŀ<F3B6A8B5><C4BF>ƿ<EFBFBD><C6BF><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD>״̬
|
||
* @param pcb the original tcp_pcb <20><><EFBFBD><EFBFBD><EFBFBD>Ŀ<EFBFBD><C4BF>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD>
|
||
* @param backlog the incoming connections queue limit
|
||
* @return tcp_pcb used for listening, consumes less memory.ָ<><D6B8><EFBFBD><EFBFBD><EFBFBD><EFBFBD>״̬<D7B4>Ŀ<EFBFBD><C4BF>ƿ<EFBFBD>
|
||
*
|
||
* @note The original tcp_pcb is freed. This function therefore has to be
|
||
* called like this:
|
||
* tpcb = tcp_listen(tpcb);
|
||
*/
|
||
struct tcp_pcb *
|
||
tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
|
||
{
|
||
struct tcp_pcb_listen *lpcb;
|
||
|
||
LWIP_UNUSED_ARG(backlog);
|
||
LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
|
||
|
||
/* already listening? */
|
||
if (pcb->state == LISTEN) {
|
||
return pcb;
|
||
}
|
||
#if SO_REUSE
|
||
if ((pcb->so_options & SOF_REUSEADDR) != 0) {
|
||
/* Since SOF_REUSEADDR allows reusing a local address before the pcb's usage
|
||
is declared (listen-/connection-pcb), we have to make sure now that
|
||
this port is only used once for every local IP. */
|
||
for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
|
||
if (lpcb->local_port == pcb->local_port) {
|
||
if (ip_addr_cmp(&lpcb->local_ip, &pcb->local_ip)) {
|
||
/* this address/port is already used */
|
||
return NULL;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
#endif /* SO_REUSE */
|
||
lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);//<2F><><EFBFBD><EFBFBD><EFBFBD>ڴ<EFBFBD>ؿռ<D8BF>
|
||
if (lpcb == NULL) {
|
||
return NULL;
|
||
}
|
||
lpcb->callback_arg = pcb->callback_arg;
|
||
lpcb->local_port = pcb->local_port;
|
||
lpcb->state = LISTEN;
|
||
lpcb->prio = pcb->prio;
|
||
lpcb->so_options = pcb->so_options;
|
||
lpcb->so_options |= SOF_ACCEPTCONN;
|
||
lpcb->ttl = pcb->ttl;
|
||
lpcb->tos = pcb->tos;
|
||
ip_addr_copy(lpcb->local_ip, pcb->local_ip);
|
||
if (pcb->local_port != 0) {
|
||
TCP_RMV(&tcp_bound_pcbs, pcb);
|
||
}
|
||
memp_free(MEMP_TCP_PCB, pcb);
|
||
#if LWIP_CALLBACK_API
|
||
lpcb->accept = tcp_accept_null;//<2F><><EFBFBD>ܿͻ<DCBF><CDBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӵ<EFBFBD>Ĭ<EFBFBD>ϻص<CFBB><D8B5><EFBFBD><EFBFBD><EFBFBD>
|
||
#endif /* LWIP_CALLBACK_API */
|
||
#if TCP_LISTEN_BACKLOG
|
||
lpcb->accepts_pending = 0;
|
||
lpcb->backlog = (backlog ? backlog : 1);
|
||
#endif /* TCP_LISTEN_BACKLOG */
|
||
TCP_REG(&tcp_listen_pcbs.pcbs, (struct tcp_pcb *)lpcb);//<2F><><EFBFBD>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD>tcp_listen_pcbs<62><73><EFBFBD><EFBFBD><EFBFBD>ײ<EFBFBD>
|
||
return (struct tcp_pcb *)lpcb;
|
||
}
|
||
|
||
/**
|
||
* Update the state that tracks the available window space to advertise.
|
||
*
|
||
* Returns how much extra window would be advertised if we sent an
|
||
* update now.
|
||
*/
|
||
u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb)
|
||
{
|
||
u32_t new_right_edge = pcb->rcv_nxt + pcb->rcv_wnd;
|
||
|
||
if (TCP_SEQ_GEQ(new_right_edge, pcb->rcv_ann_right_edge + LWIP_MIN((TCP_WND / 2), pcb->mss))) {
|
||
/* we can advertise more window */
|
||
pcb->rcv_ann_wnd = pcb->rcv_wnd;
|
||
return new_right_edge - pcb->rcv_ann_right_edge;
|
||
} else {
|
||
if (TCP_SEQ_GT(pcb->rcv_nxt, pcb->rcv_ann_right_edge)) {
|
||
/* Can happen due to other end sending out of advertised window,
|
||
* but within actual available (but not yet advertised) window */
|
||
pcb->rcv_ann_wnd = 0;
|
||
} else {
|
||
/* keep the right edge of window constant */
|
||
u32_t new_rcv_ann_wnd = pcb->rcv_ann_right_edge - pcb->rcv_nxt;
|
||
LWIP_ASSERT("new_rcv_ann_wnd <= 0xffff", new_rcv_ann_wnd <= 0xffff);
|
||
pcb->rcv_ann_wnd = (u16_t)new_rcv_ann_wnd;
|
||
}
|
||
return 0;
|
||
}
|
||
}
|
||
|
||
/**
|
||
* This function should be called by the application when it has
|
||
* processed the data. The purpose is to advertise a larger window
|
||
* when the data has been processed.
|
||
*Ӧ<>ó<EFBFBD><C3B3><EFBFBD><EFBFBD><EFBFBD>ݴ<EFBFBD><DDB4><EFBFBD><EFBFBD><EFBFBD>Ϻ<EFBFBD>֪ͨ<CDA8>ں˸<DABA><CBB8>½<EFBFBD><C2BD>մ<EFBFBD><D5B4><EFBFBD>
|
||
* @param pcb the tcp_pcb for which data is read
|
||
* @param len the amount of bytes that have been read by the application
|
||
*/
|
||
void
|
||
tcp_recved(struct tcp_pcb *pcb, u16_t len)
|
||
{
|
||
int wnd_inflation;
|
||
|
||
LWIP_ASSERT("tcp_recved: len would wrap rcv_wnd\n",
|
||
len <= 0xffff - pcb->rcv_wnd );
|
||
|
||
pcb->rcv_wnd += len;
|
||
if (pcb->rcv_wnd > TCP_WND) {
|
||
pcb->rcv_wnd = TCP_WND;
|
||
}
|
||
|
||
wnd_inflation = tcp_update_rcv_ann_wnd(pcb);
|
||
|
||
/* If the change in the right edge of window is significant (default
|
||
* watermark is TCP_WND/4), then send an explicit update now.
|
||
* Otherwise wait for a packet to be sent in the normal course of
|
||
* events (or more window to be available later) */
|
||
if (wnd_inflation >= TCP_WND_UPDATE_THRESHOLD) {
|
||
tcp_ack_now(pcb);
|
||
tcp_output(pcb);
|
||
}
|
||
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_recved: recveived %"U16_F" bytes, wnd %"U16_F" (%"U16_F").\n",
|
||
len, pcb->rcv_wnd, TCP_WND - pcb->rcv_wnd));
|
||
}
|
||
|
||
/**
|
||
* A nastly hack featuring 'goto' statements that allocates a
|
||
* new TCP local port.
|
||
*
|
||
* @return a new (free) local TCP port number
|
||
*/
|
||
static u16_t
|
||
tcp_new_port(void)
|
||
{
|
||
int i;
|
||
struct tcp_pcb *pcb;
|
||
#ifndef TCP_LOCAL_PORT_RANGE_START
|
||
#define TCP_LOCAL_PORT_RANGE_START 4096
|
||
#define TCP_LOCAL_PORT_RANGE_END 0x7fff
|
||
#endif
|
||
static u16_t port = TCP_LOCAL_PORT_RANGE_START;
|
||
|
||
again:
|
||
if (++port >= TCP_LOCAL_PORT_RANGE_END) {
|
||
port = TCP_LOCAL_PORT_RANGE_START;
|
||
}
|
||
/* Check all PCB lists. */
|
||
for (i = 0; i < NUM_TCP_PCB_LISTS; i++) {
|
||
for(pcb = *tcp_pcb_lists[i]; pcb != NULL; pcb = pcb->next) {
|
||
if (pcb->local_port == port) {
|
||
goto again;
|
||
}
|
||
}
|
||
}
|
||
return port;
|
||
}
|
||
|
||
/**
|
||
* Connects to another host. The function given as the "connected"
|
||
* argument will be called when the connection has been established.
|
||
*<2A><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><D2BB>SYN<59><4E><EFBFBD>ֱ<EFBFBD><D6B1><EFBFBD>
|
||
* @param pcb the tcp_pcb used to establish the connection <20><><EFBFBD><EFBFBD><EFBFBD>Ŀ<EFBFBD><C4BF>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD>
|
||
* @param ipaddr the remote ip address to connect to <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>IP<49><50>ַ
|
||
* @param port the remote tcp port to connect to <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˿ں<CBBF>
|
||
* @param connected callback function to call when connected (or on error)
|
||
* @return ERR_VAL if invalid arguments are given
|
||
* ERR_OK if connect request has been sent
|
||
* other err_t values if connect request couldn't be sent
|
||
*/
|
||
err_t
|
||
tcp_connect(struct tcp_pcb *pcb, ip_addr_t *ipaddr, u16_t port,
|
||
tcp_connected_fn connected)
|
||
{
|
||
err_t ret;
|
||
u32_t iss;
|
||
u16_t old_local_port;
|
||
|
||
LWIP_ERROR("tcp_connect: can only connected from state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
|
||
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect to port %"U16_F"\n", port));
|
||
if (ipaddr != NULL) {
|
||
pcb->remote_ip = *ipaddr;//<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>IP<49><50>ַ<EFBFBD><D6B7>Ч<EFBFBD><D0A7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ӽ<EFBFBD>¼<EFBFBD>м<EFBFBD>¼<EFBFBD><C2BC>IP<49><50>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD>ش<F2B7B5BB><D8B4><EFBFBD>
|
||
} else {
|
||
return ERR_VAL;
|
||
}
|
||
pcb->remote_port = port;//<2F><>¼<EFBFBD><C2BC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>˿<EFBFBD>(Ŀ<>Ķ˿<C4B6>)
|
||
|
||
/* check if we have a route to the remote host */
|
||
if (ip_addr_isany(&(pcb->local_ip))) {
|
||
/* no local IP address set, yet. */
|
||
struct netif *netif = ip_route(&(pcb->remote_ip));
|
||
if (netif == NULL) {
|
||
/* Don't even try to send a SYN packet if we have no route
|
||
since that will fail. */
|
||
return ERR_RTE;
|
||
}
|
||
/* Use the netif's IP address as local address. */
|
||
ip_addr_copy(pcb->local_ip, netif->ip_addr);
|
||
}
|
||
|
||
old_local_port = pcb->local_port;
|
||
if (pcb->local_port == 0) {
|
||
pcb->local_port = tcp_new_port();
|
||
|
||
}
|
||
#if SO_REUSE
|
||
if ((pcb->so_options & SOF_REUSEADDR) != 0) {
|
||
/* Since SOF_REUSEADDR allows reusing a local address, we have to make sure
|
||
now that the 5-tuple is unique. */
|
||
struct tcp_pcb *cpcb;
|
||
int i;
|
||
/* Don't check listen- and bound-PCBs, check active- and TIME-WAIT PCBs. */
|
||
for (i = 2; i < NUM_TCP_PCB_LISTS; i++) {
|
||
for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
|
||
if ((cpcb->local_port == pcb->local_port) &&
|
||
(cpcb->remote_port == port) &&
|
||
ip_addr_cmp(&cpcb->local_ip, &pcb->local_ip) &&
|
||
ip_addr_cmp(&cpcb->remote_ip, ipaddr)) {
|
||
/* linux returns EISCONN here, but ERR_USE should be OK for us */
|
||
return ERR_USE;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
#endif /* SO_REUSE */
|
||
iss = tcp_next_iss();//<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD>
|
||
pcb->rcv_nxt = 0;//<2F><><EFBFBD>÷<EFBFBD><C3B7>ʹ<EFBFBD><CDB4>ڵĸ<DAB5><C4B8><EFBFBD><EFBFBD>ֶ<EFBFBD>
|
||
pcb->snd_nxt = iss;
|
||
pcb->lastack = iss - 1;
|
||
pcb->snd_lbb = iss - 1;
|
||
pcb->rcv_wnd = TCP_WND;//<2F><><EFBFBD><EFBFBD>Ĭ<EFBFBD>Ͻ<EFBFBD><CFBD>մ<EFBFBD><D5B4>ڸ<EFBFBD><DAB8><EFBFBD><EFBFBD>ֶ<EFBFBD>ֵ
|
||
pcb->rcv_ann_wnd = TCP_WND;
|
||
pcb->rcv_ann_right_edge = pcb->rcv_nxt;
|
||
pcb->snd_wnd = TCP_WND;
|
||
/* As initial send MSS, we use TCP_MSS but limit it to 536.
|
||
The send MSS is updated when an MSS option is received. */
|
||
pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;//<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ķδ<C4B6>С
|
||
#if TCP_CALCULATE_EFF_SEND_MSS
|
||
pcb->mss = tcp_eff_send_mss(pcb->mss, ipaddr);
|
||
#endif /* TCP_CALCULATE_EFF_SEND_MSS */
|
||
pcb->cwnd = 1;//<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||
pcb->ssthresh = pcb->mss * 10;
|
||
#if LWIP_CALLBACK_API
|
||
pcb->connected = connected;//ע<><D7A2>connected<65>ص<EFBFBD><D8B5><EFBFBD><EFBFBD><EFBFBD>
|
||
#else /* LWIP_CALLBACK_API */
|
||
LWIP_UNUSED_ARG(connected);
|
||
#endif /* LWIP_CALLBACK_API */
|
||
|
||
/* Send a SYN together with the MSS option. */
|
||
ret = tcp_enqueue_flags(pcb, TCP_SYN);
|
||
if (ret == ERR_OK) {
|
||
/* SYN segment was enqueued, changed the pcbs state now <20><><EFBFBD>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD><EFBFBD>ΪSYN_SENT ״̬*/
|
||
pcb->state = SYN_SENT;
|
||
if (old_local_port != 0) {
|
||
TCP_RMV(&tcp_bound_pcbs, pcb);
|
||
}
|
||
TCP_REG(&tcp_active_pcbs, pcb);
|
||
snmp_inc_tcpactiveopens();
|
||
|
||
tcp_output(pcb);//<2F><><EFBFBD><EFBFBD><EFBFBD>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӵı<D3B5><C4B1>ķ<EFBFBD><C4B7>ͳ<EFBFBD>ȥ
|
||
}
|
||
return ret;
|
||
}
|
||
|
||
/**
|
||
* Called every 500 ms and implements the retransmission timer and the timer that
|
||
* removes PCBs that have been in TIME-WAIT for enough time. It also increments
|
||
* various timers such as the inactivity timer in each PCB.
|
||
*
|
||
* Automatically called from tcp_tmr().
|
||
*/
|
||
void
|
||
tcp_slowtmr(void)
|
||
{
|
||
struct tcp_pcb *pcb, *prev;
|
||
u16_t eff_wnd;
|
||
u8_t pcb_remove; /* flag if a PCB should be removed */
|
||
u8_t pcb_reset; /* flag if a RST should be sent when removing */
|
||
err_t err;
|
||
|
||
err = ERR_OK;
|
||
|
||
++tcp_ticks;
|
||
|
||
/* Steps through all of the active PCBs. */
|
||
prev = NULL;
|
||
pcb = tcp_active_pcbs;
|
||
if (pcb == NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: no active pcbs\n"));
|
||
}
|
||
while (pcb != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: processing active pcb\n"));
|
||
LWIP_ASSERT("tcp_slowtmr: active pcb->state != CLOSED\n", pcb->state != CLOSED);
|
||
LWIP_ASSERT("tcp_slowtmr: active pcb->state != LISTEN\n", pcb->state != LISTEN);
|
||
LWIP_ASSERT("tcp_slowtmr: active pcb->state != TIME-WAIT\n", pcb->state != TIME_WAIT);
|
||
|
||
pcb_remove = 0;
|
||
pcb_reset = 0;
|
||
|
||
if (pcb->state == SYN_SENT && pcb->nrtx == TCP_SYNMAXRTX) {
|
||
++pcb_remove;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max SYN retries reached\n"));
|
||
}
|
||
else if (pcb->nrtx == TCP_MAXRTX) {
|
||
++pcb_remove;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max DATA retries reached\n"));
|
||
} else {
|
||
if (pcb->persist_backoff > 0) {
|
||
/* If snd_wnd is zero, use persist timer to send 1 byte probes
|
||
* instead of using the standard retransmission mechanism. */
|
||
pcb->persist_cnt++;
|
||
if (pcb->persist_cnt >= system_get_data_of_array_8(tcp_persist_backoff, pcb->persist_backoff-1)) {
|
||
pcb->persist_cnt = 0;
|
||
if (pcb->persist_backoff < sizeof(tcp_persist_backoff)) {
|
||
pcb->persist_backoff++;
|
||
}
|
||
tcp_zero_window_probe(pcb);
|
||
}
|
||
} else {
|
||
/* Increase the retransmission timer if it is running */
|
||
if(pcb->rtime >= 0)
|
||
++pcb->rtime;
|
||
|
||
if (pcb->unacked != NULL && pcb->rtime >= pcb->rto) {
|
||
/* Time for a retransmission. */
|
||
LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_slowtmr: rtime %"S16_F
|
||
" pcb->rto %"S16_F"\n",
|
||
pcb->rtime, pcb->rto));
|
||
|
||
/* Double retransmission time-out unless we are trying to
|
||
* connect to somebody (i.e., we are in SYN_SENT). */
|
||
if (pcb->state != SYN_SENT) {
|
||
pcb->rto = ((pcb->sa >> 3) + pcb->sv) << system_get_data_of_array_8(tcp_backoff, pcb->nrtx);
|
||
// if (pcb->rto >= TCP_MAXRTO)
|
||
// pcb->rto >>= 1;
|
||
}
|
||
|
||
/* Reset the retransmission timer. */
|
||
pcb->rtime = 0;
|
||
|
||
/* Reduce congestion window and ssthresh. */
|
||
eff_wnd = LWIP_MIN(pcb->cwnd, pcb->snd_wnd);
|
||
pcb->ssthresh = eff_wnd >> 1;
|
||
if (pcb->ssthresh < (pcb->mss << 1)) {
|
||
pcb->ssthresh = (pcb->mss << 1);
|
||
}
|
||
pcb->cwnd = pcb->mss;
|
||
LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: cwnd %"U16_F
|
||
" ssthresh %"U16_F"\n",
|
||
pcb->cwnd, pcb->ssthresh));
|
||
|
||
/* The following needs to be called AFTER cwnd is set to one
|
||
mss - STJ */
|
||
tcp_rexmit_rto(pcb);
|
||
}
|
||
}
|
||
}
|
||
/* Check if this PCB has stayed too long in FIN-WAIT-2 */
|
||
if (pcb->state == FIN_WAIT_2) {
|
||
if ((u32_t)(tcp_ticks - pcb->tmr) >
|
||
TCP_FIN_WAIT_TIMEOUT / TCP_SLOW_INTERVAL) {
|
||
++pcb_remove;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in FIN-WAIT-2\n"));
|
||
}
|
||
}
|
||
|
||
/* Check if KEEPALIVE should be sent */
|
||
if((pcb->so_options & SOF_KEEPALIVE) &&
|
||
((pcb->state == ESTABLISHED) ||
|
||
(pcb->state == CLOSE_WAIT))) {
|
||
#if LWIP_TCP_KEEPALIVE
|
||
if((u32_t)(tcp_ticks - pcb->tmr) >
|
||
(pcb->keep_idle + (pcb->keep_cnt*pcb->keep_intvl))
|
||
/ TCP_SLOW_INTERVAL)
|
||
#else
|
||
if((u32_t)(tcp_ticks - pcb->tmr) >
|
||
(pcb->keep_idle + TCP_MAXIDLE) / TCP_SLOW_INTERVAL)
|
||
#endif /* LWIP_TCP_KEEPALIVE */
|
||
{
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: KEEPALIVE timeout. Aborting connection to %"U16_F".%"U16_F".%"U16_F".%"U16_F".\n",
|
||
ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
|
||
ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
|
||
|
||
++pcb_remove;
|
||
++pcb_reset;
|
||
}
|
||
#if LWIP_TCP_KEEPALIVE
|
||
else if((u32_t)(tcp_ticks - pcb->tmr) >
|
||
(pcb->keep_idle + pcb->keep_cnt_sent * pcb->keep_intvl)
|
||
/ TCP_SLOW_INTERVAL)
|
||
#else
|
||
else if((u32_t)(tcp_ticks - pcb->tmr) >
|
||
(pcb->keep_idle + pcb->keep_cnt_sent * TCP_KEEPINTVL_DEFAULT)
|
||
/ TCP_SLOW_INTERVAL)
|
||
#endif /* LWIP_TCP_KEEPALIVE */
|
||
{
|
||
tcp_keepalive(pcb);
|
||
pcb->keep_cnt_sent++;
|
||
}
|
||
}
|
||
|
||
/* If this PCB has queued out of sequence data, but has been
|
||
inactive for too long, will drop the data (it will eventually
|
||
be retransmitted). */
|
||
#if TCP_QUEUE_OOSEQ
|
||
if (pcb->ooseq != NULL &&
|
||
(u32_t)tcp_ticks - pcb->tmr >= pcb->rto * TCP_OOSEQ_TIMEOUT) {
|
||
tcp_segs_free(pcb->ooseq);
|
||
pcb->ooseq = NULL;
|
||
LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: dropping OOSEQ queued data\n"));
|
||
}
|
||
#endif /* TCP_QUEUE_OOSEQ */
|
||
|
||
/* Check if this PCB has stayed too long in SYN-RCVD */
|
||
if (pcb->state == SYN_RCVD) {
|
||
if ((u32_t)(tcp_ticks - pcb->tmr) >
|
||
TCP_SYN_RCVD_TIMEOUT / TCP_SLOW_INTERVAL) {
|
||
++pcb_remove;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in SYN-RCVD\n"));
|
||
}
|
||
}
|
||
|
||
/* Check if this PCB has stayed too long in LAST-ACK */
|
||
if (pcb->state == LAST_ACK) {
|
||
if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
|
||
++pcb_remove;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in LAST-ACK\n"));
|
||
}
|
||
}
|
||
|
||
/* If the PCB should be removed, do it. */
|
||
if (pcb_remove) {
|
||
struct tcp_pcb *pcb2;
|
||
tcp_pcb_purge(pcb);
|
||
/* Remove PCB from tcp_active_pcbs list. */
|
||
if (prev != NULL) {
|
||
LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_active_pcbs", pcb != tcp_active_pcbs);
|
||
prev->next = pcb->next;
|
||
} else {
|
||
/* This PCB was the first. */
|
||
LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_active_pcbs", tcp_active_pcbs == pcb);
|
||
tcp_active_pcbs = pcb->next;
|
||
}
|
||
|
||
if (pcb_reset) {
|
||
tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
|
||
pcb->local_port, pcb->remote_port);
|
||
}
|
||
|
||
TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_ABRT);
|
||
pcb2 = pcb;
|
||
pcb = pcb->next;
|
||
memp_free(MEMP_TCP_PCB, pcb2);
|
||
} else {
|
||
/* get the 'next' element now and work with 'prev' below (in case of abort) */
|
||
prev = pcb;
|
||
pcb = pcb->next;
|
||
|
||
/* We check if we should poll the connection. */
|
||
++prev->polltmr;
|
||
if (prev->polltmr >= prev->pollinterval) {
|
||
prev->polltmr = 0;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: polling application\n"));
|
||
TCP_EVENT_POLL(prev, err);
|
||
/* if err == ERR_ABRT, 'prev' is already deallocated */
|
||
if (err == ERR_OK) {
|
||
tcp_output(prev);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
|
||
/* Steps through all of the TIME-WAIT PCBs. */
|
||
prev = NULL;
|
||
pcb = tcp_tw_pcbs;
|
||
while (pcb != NULL) {
|
||
LWIP_ASSERT("tcp_slowtmr: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
|
||
pcb_remove = 0;
|
||
|
||
/* Check if this PCB has stayed long enough in TIME-WAIT */
|
||
if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
|
||
++pcb_remove;
|
||
}
|
||
|
||
|
||
|
||
/* If the PCB should be removed, do it. */
|
||
if (pcb_remove) {
|
||
struct tcp_pcb *pcb2;
|
||
tcp_pcb_purge(pcb);
|
||
/* Remove PCB from tcp_tw_pcbs list. */
|
||
if (prev != NULL) {
|
||
LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_tw_pcbs", pcb != tcp_tw_pcbs);
|
||
prev->next = pcb->next;
|
||
} else {
|
||
/* This PCB was the first. */
|
||
LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_tw_pcbs", tcp_tw_pcbs == pcb);
|
||
tcp_tw_pcbs = pcb->next;
|
||
}
|
||
pcb2 = pcb;
|
||
pcb = pcb->next;
|
||
memp_free(MEMP_TCP_PCB, pcb2);
|
||
} else {
|
||
prev = pcb;
|
||
pcb = pcb->next;
|
||
}
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Is called every TCP_FAST_INTERVAL (250 ms) and process data previously
|
||
* "refused" by upper layer (application) and sends delayed ACKs.
|
||
*
|
||
* Automatically called from tcp_tmr().
|
||
*/
|
||
void
|
||
tcp_fasttmr(void)
|
||
{
|
||
struct tcp_pcb *pcb = tcp_active_pcbs;
|
||
|
||
while(pcb != NULL) {
|
||
struct tcp_pcb *next = pcb->next;
|
||
/* If there is data which was previously "refused" by upper layer */
|
||
if (pcb->refused_data != NULL) {
|
||
/* Notify again application with data previously received. */
|
||
err_t err;
|
||
LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_fasttmr: notify kept packet\n"));
|
||
TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
|
||
if (err == ERR_OK) {
|
||
pcb->refused_data = NULL;
|
||
} else if (err == ERR_ABRT) {
|
||
/* if err == ERR_ABRT, 'pcb' is already deallocated */
|
||
pcb = NULL;
|
||
}
|
||
}
|
||
|
||
/* send delayed ACKs */
|
||
if (pcb && (pcb->flags & TF_ACK_DELAY)) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_fasttmr: delayed ACK\n"));
|
||
tcp_ack_now(pcb);
|
||
tcp_output(pcb);
|
||
pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
|
||
}
|
||
|
||
pcb = next;
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Deallocates a list of TCP segments (tcp_seg structures).
|
||
*
|
||
* @param seg tcp_seg list of TCP segments to free
|
||
*/
|
||
void
|
||
tcp_segs_free(struct tcp_seg *seg)
|
||
{
|
||
while (seg != NULL) {
|
||
struct tcp_seg *next = seg->next;
|
||
tcp_seg_free(seg);
|
||
seg = next;
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Frees a TCP segment (tcp_seg structure).
|
||
*
|
||
* @param seg single tcp_seg to free
|
||
*/
|
||
void
|
||
tcp_seg_free(struct tcp_seg *seg)
|
||
{
|
||
if (seg != NULL) {
|
||
if (seg->p != NULL) {
|
||
pbuf_free(seg->p);
|
||
#if TCP_DEBUG
|
||
seg->p = NULL;
|
||
#endif /* TCP_DEBUG */
|
||
}
|
||
memp_free(MEMP_TCP_SEG, seg);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Sets the priority of a connection.
|
||
*
|
||
* @param pcb the tcp_pcb to manipulate
|
||
* @param prio new priority
|
||
*/
|
||
void
|
||
tcp_setprio(struct tcp_pcb *pcb, u8_t prio)
|
||
{
|
||
pcb->prio = prio;
|
||
}
|
||
|
||
#if TCP_QUEUE_OOSEQ
|
||
/**
|
||
* Returns a copy of the given TCP segment.
|
||
* The pbuf and data are not copied, only the pointers
|
||
*
|
||
* @param seg the old tcp_seg
|
||
* @return a copy of seg
|
||
*/
|
||
struct tcp_seg *
|
||
tcp_seg_copy(struct tcp_seg *seg)
|
||
{
|
||
struct tcp_seg *cseg;
|
||
|
||
cseg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG);
|
||
if (cseg == NULL) {
|
||
return NULL;
|
||
}
|
||
SMEMCPY((u8_t *)cseg, (const u8_t *)seg, sizeof(struct tcp_seg));
|
||
pbuf_ref(cseg->p);
|
||
return cseg;
|
||
}
|
||
#endif /* TCP_QUEUE_OOSEQ */
|
||
|
||
#if LWIP_CALLBACK_API
|
||
/**
|
||
* Default receive callback that is called if the user didn't register
|
||
* a recv callback for the pcb.
|
||
*/
|
||
err_t
|
||
tcp_recv_null(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
|
||
{
|
||
LWIP_UNUSED_ARG(arg);
|
||
if (p != NULL) {
|
||
tcp_recved(pcb, p->tot_len);
|
||
pbuf_free(p);
|
||
} else if (err == ERR_OK) {
|
||
return tcp_close(pcb);
|
||
}
|
||
return ERR_OK;
|
||
}
|
||
#endif /* LWIP_CALLBACK_API */
|
||
|
||
/**
|
||
* Kills the oldest active connection that has lower priority than prio.
|
||
*
|
||
* @param prio minimum priority
|
||
*/
|
||
static void ICACHE_FLASH_ATTR
|
||
tcp_kill_prio(u8_t prio)
|
||
{
|
||
struct tcp_pcb *pcb, *inactive;
|
||
u32_t inactivity;
|
||
u8_t mprio;
|
||
|
||
|
||
mprio = TCP_PRIO_MAX;
|
||
|
||
/* We kill the oldest active connection that has lower priority than prio. */
|
||
inactivity = 0;
|
||
inactive = NULL;
|
||
for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
|
||
if (pcb->prio <= prio &&
|
||
pcb->prio <= mprio &&
|
||
(u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
|
||
inactivity = tcp_ticks - pcb->tmr;
|
||
inactive = pcb;
|
||
mprio = pcb->prio;
|
||
}
|
||
}
|
||
if (inactive != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_prio: killing oldest PCB %p (%"S32_F")\n",
|
||
(void *)inactive, inactivity));
|
||
tcp_abort(inactive);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Kills the oldest connection that is in TIME_WAIT state.
|
||
* Called from tcp_alloc() if no more connections are available.
|
||
*/
|
||
static void ICACHE_FLASH_ATTR
|
||
tcp_kill_timewait(void)
|
||
{
|
||
struct tcp_pcb *pcb, *inactive;
|
||
u32_t inactivity;
|
||
|
||
inactivity = 0;
|
||
inactive = NULL;
|
||
/* Go through the list of TIME_WAIT pcbs and get the oldest pcb. */
|
||
for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
|
||
if ((u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
|
||
inactivity = tcp_ticks - pcb->tmr;
|
||
inactive = pcb;
|
||
}
|
||
}
|
||
if (inactive != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_timewait: killing oldest TIME-WAIT PCB %p (%"S32_F")\n",
|
||
(void *)inactive, inactivity));
|
||
tcp_abort(inactive);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Allocate a new tcp_pcb structure.
|
||
*<2A><><EFBFBD><EFBFBD>һ<EFBFBD><D2BB>TCP<43><50><EFBFBD>ƿ<EFBFBD>ṹ<EFBFBD><E1B9B9><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֶ<EFBFBD>
|
||
* @param prio priority for the new pcb <09>¿<EFBFBD><C2BF>ƿ<EFBFBD><C6BF><EFBFBD><EFBFBD><EFBFBD>ȼ<EFBFBD>
|
||
* @return a new tcp_pcb that initially is in state CLOSED ָ<><D6B8><EFBFBD>¿<EFBFBD><C2BF>ƿ<EFBFBD><C6BF>ָ<EFBFBD><D6B8>
|
||
*/
|
||
struct tcp_pcb *
|
||
tcp_alloc(u8_t prio)
|
||
{
|
||
struct tcp_pcb *pcb;
|
||
u32_t iss;
|
||
|
||
pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);//<2F><><EFBFBD><EFBFBD><EFBFBD>ڴ<EFBFBD>ؿռ<D8BF>
|
||
if (pcb == NULL) {
|
||
//os_printf("tcp_pcb memory is fail\n");
|
||
/* Try killing oldest connection in TIME-WAIT. */
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing off oldest TIME-WAIT connection\n"));
|
||
tcp_kill_timewait();
|
||
/* Try to allocate a tcp_pcb again. */
|
||
pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
|
||
if (pcb == NULL) {
|
||
/* Try killing active connections with lower priority than the new one. */
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing connection with prio lower than %d\n", prio));
|
||
tcp_kill_prio(prio);
|
||
/* Try to allocate a tcp_pcb again. */
|
||
pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
|
||
if (pcb != NULL) {
|
||
/* adjust err stats: memp_malloc failed twice before */
|
||
MEMP_STATS_DEC(err, MEMP_TCP_PCB);
|
||
}
|
||
}
|
||
if (pcb != NULL) {
|
||
/* adjust err stats: timewait PCB was freed above */
|
||
MEMP_STATS_DEC(err, MEMP_TCP_PCB);
|
||
}
|
||
}
|
||
if (pcb != NULL) {
|
||
os_memset(pcb, 0, sizeof(struct tcp_pcb)); //<2F><>0
|
||
pcb->prio = prio; //<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȼ<EFBFBD>
|
||
pcb->snd_buf = TCP_SND_BUF; //<2F><>ʹ<EFBFBD>õķ<C3B5><C4B7>ͻ<EFBFBD><CDBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>С
|
||
pcb->snd_queuelen = 0; //<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ռ<EFBFBD>õ<EFBFBD>pbuf<75><66><EFBFBD><EFBFBD>
|
||
pcb->rcv_wnd = TCP_WND; //<2F><><EFBFBD>մ<EFBFBD><D5B4><EFBFBD>
|
||
pcb->rcv_ann_wnd = TCP_WND; //ͨ<><CDA8><EFBFBD><EFBFBD>մ<EFBFBD><D5B4><EFBFBD>
|
||
pcb->tos = 0; //<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||
pcb->ttl = TCP_TTL; //ttl<74>ֶ<EFBFBD>
|
||
/* As initial send MSS, we use TCP_MSS but limit it to 536.
|
||
The send MSS is updated when an MSS option is received. */
|
||
pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS; //<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ķ<EFBFBD>
|
||
pcb->rto = 1000 / TCP_SLOW_INTERVAL; //<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD>ʱʱ<CAB1><CAB1>
|
||
pcb->sa = 0; //<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD>RTT<54><54>صIJ<D8B5><C4B2><EFBFBD>
|
||
pcb->sv = 1000 / TCP_SLOW_INTERVAL;
|
||
pcb->rtime = -1;
|
||
pcb->cwnd = 1; //<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||
iss = tcp_next_iss(); //<2F><>ó<EFBFBD>ʼ<EFBFBD><CABC><EFBFBD>к<EFBFBD>
|
||
pcb->snd_wl2 = iss; //<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD><EFBFBD>ʹ<EFBFBD><CDB4>ڸ<EFBFBD><DAB8><EFBFBD><EFBFBD>ֶ<EFBFBD>
|
||
pcb->snd_nxt = iss;
|
||
pcb->lastack = iss;
|
||
pcb->snd_lbb = iss;
|
||
pcb->tmr = tcp_ticks; //<2F><>¼<EFBFBD><C2BC><EFBFBD>ƿ鴴<C6BF><E9B4B4>ϵͳʱ<CDB3><CAB1>
|
||
|
||
pcb->polltmr = 0; //<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>¼<EFBFBD><C2BC><EFBFBD>ʱ<EFBFBD><CAB1>
|
||
|
||
#if LWIP_CALLBACK_API
|
||
pcb->recv = tcp_recv_null; //ע<><D7A2><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ݵ<EFBFBD>Ĭ<EFBFBD><C4AC><EFBFBD>ϲ㺯<CFB2><E3BAAF>
|
||
#endif /* LWIP_CALLBACK_API */
|
||
|
||
/* Init KEEPALIVE timer */
|
||
pcb->keep_idle = TCP_KEEPIDLE_DEFAULT;
|
||
|
||
#if LWIP_TCP_KEEPALIVE
|
||
pcb->keep_intvl = TCP_KEEPINTVL_DEFAULT;
|
||
pcb->keep_cnt = TCP_KEEPCNT_DEFAULT;
|
||
#endif /* LWIP_TCP_KEEPALIVE */
|
||
|
||
pcb->keep_cnt_sent = 0; //<2F><><EFBFBD>ķ<EFBFBD><C4B7>ʹ<EFBFBD><CDB4><EFBFBD>
|
||
}
|
||
return pcb;
|
||
}
|
||
|
||
/**
|
||
* Creates a new TCP protocol control block but doesn't place it on
|
||
* any of the TCP PCB lists.
|
||
* The pcb is not put on any list until binding using tcp_bind().
|
||
*
|
||
* @internal: Maybe there should be a idle TCP PCB list where these
|
||
* PCBs are put on. Port reservation using tcp_bind() is implemented but
|
||
* allocated pcbs that are not bound can't be killed automatically if wanting
|
||
* to allocate a pcb with higher prio (@see tcp_kill_prio())
|
||
*
|
||
* @return a new tcp_pcb that initially is in state CLOSED
|
||
*/
|
||
struct tcp_pcb *
|
||
tcp_new(void)
|
||
{
|
||
return tcp_alloc(TCP_PRIO_NORMAL);
|
||
}
|
||
|
||
/**
|
||
* Used to specify the argument that should be passed callback
|
||
* functions.
|
||
*<2A><><EFBFBD><EFBFBD>ƿ<EFBFBD><C6BF>callback_arg<72>ֶ<EFBFBD>ע<EFBFBD><D7A2><EFBFBD>û<EFBFBD><C3BB><EFBFBD>ݣ<EFBFBD><DDA3><EFBFBD>tcp_recv<63>Ⱥ<EFBFBD><C8BA><EFBFBD>ص<EFBFBD>ʱ<EFBFBD><CAB1>
|
||
* <20><><EFBFBD>ֶν<D6B6><CEBD><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD>ݸ<EFBFBD><DDB8><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
|
||
* @param pcb tcp_pcb to set the callback argument
|
||
* @param arg void pointer argument to pass to callback functions
|
||
*/
|
||
void
|
||
tcp_arg(struct tcp_pcb *pcb, void *arg)
|
||
{
|
||
pcb->callback_arg = arg;
|
||
}
|
||
#if LWIP_CALLBACK_API
|
||
|
||
/**
|
||
* Used to specify the function that should be called when a TCP
|
||
* connection receives data.
|
||
*<2A><><EFBFBD><EFBFBD>ƿ<EFBFBD><C6BF>recv<63>ֶ<EFBFBD>ע<EFBFBD>ắ<EFBFBD><E1BAAF><EFBFBD>յ<EFBFBD><D5B5><EFBFBD><EFBFBD>ʱ<EFBFBD>ص<EFBFBD>
|
||
* @param pcb tcp_pcb to set the recv callback
|
||
* @param recv callback function to call for this pcb when data is received
|
||
*/
|
||
void
|
||
tcp_recv(struct tcp_pcb *pcb, tcp_recv_fn recv)
|
||
{
|
||
pcb->recv = recv;
|
||
}
|
||
|
||
/**
|
||
* Used to specify the function that should be called when TCP data
|
||
* has been successfully delivered to the remote host.
|
||
*<2A><><EFBFBD><EFBFBD>ƿ<EFBFBD>send <20>ֶ<EFBFBD>ע<EFBFBD>ắ<EFBFBD><E1BAAF><EFBFBD><EFBFBD>ݷ<EFBFBD><DDB7>ͳɹ<CDB3><C9B9><EFBFBD>ص<EFBFBD>
|
||
* @param pcb tcp_pcb to set the sent callback
|
||
* @param sent callback function to call for this pcb when data is successfully sent
|
||
*/
|
||
void
|
||
tcp_sent(struct tcp_pcb *pcb, tcp_sent_fn sent)
|
||
{
|
||
pcb->sent = sent;
|
||
}
|
||
|
||
/**
|
||
* Used to specify the function that should be called when a fatal error
|
||
* has occured on the connection.
|
||
*<2A><><EFBFBD><EFBFBD>ƿ<EFBFBD>err <20>ֶ<EFBFBD>ע<EFBFBD>ắ<EFBFBD><E1BAAF><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ص<EFBFBD>
|
||
* @param pcb tcp_pcb to set the err callback
|
||
* @param err callback function to call for this pcb when a fatal error
|
||
* has occured on the connection
|
||
*/
|
||
void
|
||
tcp_err(struct tcp_pcb *pcb, tcp_err_fn err)
|
||
{
|
||
pcb->errf = err;
|
||
}
|
||
|
||
/**
|
||
* Used for specifying the function that should be called when a
|
||
* LISTENing connection has been connected to another host.
|
||
*<2A><><EFBFBD><EFBFBD>ƿ<EFBFBD><C6BF>accept<70>ֶ<EFBFBD>ע<EFBFBD>ắ<EFBFBD><E1BAAF><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD>ص<EFBFBD>
|
||
* @param pcb tcp_pcb to set the accept callback
|
||
* @param accept callback function to call for this pcb when LISTENing
|
||
* connection has been connected to another host
|
||
*/
|
||
void
|
||
tcp_accept(struct tcp_pcb *pcb, tcp_accept_fn accept)
|
||
{
|
||
pcb->accept = accept;
|
||
}
|
||
#endif /* LWIP_CALLBACK_API */
|
||
|
||
|
||
/**
|
||
* Used to specify the function that should be called periodically
|
||
* from TCP. The interval is specified in terms of the TCP coarse
|
||
* timer interval, which is called twice a second.
|
||
*<2A><><EFBFBD><EFBFBD>ƿ<EFBFBD><C6BF>POLL<4C>ֶ<EFBFBD>ע<EFBFBD>ắ<EFBFBD><E1BAAF>ú<EFBFBD><C3BA><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ա<EFBFBD><D4B1><EFBFBD><EFBFBD><EFBFBD>
|
||
*/
|
||
void
|
||
tcp_poll(struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval)
|
||
{
|
||
#if LWIP_CALLBACK_API
|
||
pcb->poll = poll;
|
||
#else /* LWIP_CALLBACK_API */
|
||
LWIP_UNUSED_ARG(poll);
|
||
#endif /* LWIP_CALLBACK_API */
|
||
pcb->pollinterval = interval;
|
||
}
|
||
|
||
/**
|
||
* Purges a TCP PCB. Removes any buffered data and frees the buffer memory
|
||
* (pcb->ooseq, pcb->unsent and pcb->unacked are freed).
|
||
*
|
||
* @param pcb tcp_pcb to purge. The pcb itself is not deallocated!
|
||
*/
|
||
void
|
||
tcp_pcb_purge(struct tcp_pcb *pcb)
|
||
{
|
||
if (pcb->state != CLOSED &&
|
||
pcb->state != TIME_WAIT &&
|
||
pcb->state != LISTEN) {
|
||
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge\n"));
|
||
|
||
#if TCP_LISTEN_BACKLOG
|
||
if (pcb->state == SYN_RCVD) {
|
||
/* Need to find the corresponding listen_pcb and decrease its accepts_pending */
|
||
struct tcp_pcb_listen *lpcb;
|
||
LWIP_ASSERT("tcp_pcb_purge: pcb->state == SYN_RCVD but tcp_listen_pcbs is NULL",
|
||
tcp_listen_pcbs.listen_pcbs != NULL);
|
||
for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
|
||
if ((lpcb->local_port == pcb->local_port) &&
|
||
(ip_addr_isany(&lpcb->local_ip) ||
|
||
ip_addr_cmp(&pcb->local_ip, &lpcb->local_ip))) {
|
||
/* port and address of the listen pcb match the timed-out pcb */
|
||
LWIP_ASSERT("tcp_pcb_purge: listen pcb does not have accepts pending",
|
||
lpcb->accepts_pending > 0);
|
||
lpcb->accepts_pending--;
|
||
break;
|
||
}
|
||
}
|
||
}
|
||
#endif /* TCP_LISTEN_BACKLOG */
|
||
|
||
|
||
if (pcb->refused_data != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->refused_data\n"));
|
||
pbuf_free(pcb->refused_data);
|
||
pcb->refused_data = NULL;
|
||
}
|
||
if (pcb->unsent != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: not all data sent\n"));
|
||
}
|
||
if (pcb->unacked != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->unacked\n"));
|
||
}
|
||
#if TCP_QUEUE_OOSEQ
|
||
if (pcb->ooseq != NULL) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->ooseq\n"));
|
||
}
|
||
tcp_segs_free(pcb->ooseq);
|
||
pcb->ooseq = NULL;
|
||
#endif /* TCP_QUEUE_OOSEQ */
|
||
|
||
/* Stop the retransmission timer as it will expect data on unacked
|
||
queue if it fires */
|
||
pcb->rtime = -1;
|
||
|
||
tcp_segs_free(pcb->unsent);
|
||
tcp_segs_free(pcb->unacked);
|
||
pcb->unacked = pcb->unsent = NULL;
|
||
#if TCP_OVERSIZE
|
||
pcb->unsent_oversize = 0;
|
||
#endif /* TCP_OVERSIZE */
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Purges the PCB and removes it from a PCB list. Any delayed ACKs are sent first.
|
||
*
|
||
* @param pcblist PCB list to purge.
|
||
* @param pcb tcp_pcb to purge. The pcb itself is NOT deallocated!
|
||
*/
|
||
void
|
||
tcp_pcb_remove(struct tcp_pcb **pcblist, struct tcp_pcb *pcb)
|
||
{
|
||
TCP_RMV(pcblist, pcb);
|
||
|
||
tcp_pcb_purge(pcb);
|
||
|
||
/* if there is an outstanding delayed ACKs, send it */
|
||
if (pcb->state != TIME_WAIT &&
|
||
pcb->state != LISTEN &&
|
||
pcb->flags & TF_ACK_DELAY) {
|
||
pcb->flags |= TF_ACK_NOW;
|
||
tcp_output(pcb);
|
||
}
|
||
|
||
if (pcb->state != LISTEN) {
|
||
LWIP_ASSERT("unsent segments leaking", pcb->unsent == NULL);
|
||
LWIP_ASSERT("unacked segments leaking", pcb->unacked == NULL);
|
||
#if TCP_QUEUE_OOSEQ
|
||
LWIP_ASSERT("ooseq segments leaking", pcb->ooseq == NULL);
|
||
#endif /* TCP_QUEUE_OOSEQ */
|
||
}
|
||
|
||
pcb->state = CLOSED;
|
||
|
||
LWIP_ASSERT("tcp_pcb_remove: tcp_pcbs_sane()", tcp_pcbs_sane());
|
||
}
|
||
|
||
/**
|
||
* Calculates a new initial sequence number for new connections.
|
||
*
|
||
* @return u32_t pseudo random sequence number
|
||
*/
|
||
u32_t
|
||
tcp_next_iss(void)
|
||
{
|
||
static u32_t iss = 6510;
|
||
|
||
again:
|
||
iss += tcp_ticks; /* XXX */
|
||
if (iss == 0)
|
||
goto again;
|
||
|
||
return iss;
|
||
}
|
||
|
||
#if TCP_CALCULATE_EFF_SEND_MSS
|
||
/**
|
||
* Calcluates the effective send mss that can be used for a specific IP address
|
||
* by using ip_route to determin the netif used to send to the address and
|
||
* calculating the minimum of TCP_MSS and that netif's mtu (if set).
|
||
*/
|
||
u16_t
|
||
tcp_eff_send_mss(u16_t sendmss, ip_addr_t *addr)
|
||
{
|
||
u16_t mss_s;
|
||
struct netif *outif;
|
||
|
||
outif = ip_route(addr);
|
||
if ((outif != NULL) && (outif->mtu != 0)) {
|
||
mss_s = outif->mtu - IP_HLEN - TCP_HLEN;
|
||
/* RFC 1122, chap 4.2.2.6:
|
||
* Eff.snd.MSS = min(SendMSS+20, MMS_S) - TCPhdrsize - IPoptionsize
|
||
* We correct for TCP options in tcp_write(), and don't support IP options.
|
||
*/
|
||
sendmss = LWIP_MIN(sendmss, mss_s);
|
||
}
|
||
return sendmss;
|
||
}
|
||
#endif /* TCP_CALCULATE_EFF_SEND_MSS */
|
||
|
||
#if TCP_DEBUG
|
||
const char*
|
||
tcp_debug_state_str(enum tcp_state s)
|
||
{
|
||
system_get_string_from_flash(tcp_state_str_rodata[s], tcp_state_str, 12);
|
||
|
||
return tcp_state_str;
|
||
}
|
||
#endif
|
||
|
||
#if TCP_DEBUG || TCP_INPUT_DEBUG || TCP_OUTPUT_DEBUG
|
||
/**
|
||
* Print a tcp header for debugging purposes.
|
||
*
|
||
* @param tcphdr pointer to a struct tcp_hdr
|
||
*/
|
||
void
|
||
tcp_debug_print(struct tcp_hdr *tcphdr)
|
||
{
|
||
LWIP_DEBUGF(TCP_DEBUG, ("TCP header:\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("| %5"U16_F" | %5"U16_F" | (src port, dest port)\n",
|
||
ntohs(tcphdr->src), ntohs(tcphdr->dest)));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("| %010"U32_F" | (seq no)\n",
|
||
ntohl(tcphdr->seqno)));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("| %010"U32_F" | (ack no)\n",
|
||
ntohl(tcphdr->ackno)));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("| %2"U16_F" | |%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"| %5"U16_F" | (hdrlen, flags (",
|
||
TCPH_HDRLEN(tcphdr),
|
||
TCPH_FLAGS(tcphdr) >> 5 & 1,
|
||
TCPH_FLAGS(tcphdr) >> 4 & 1,
|
||
TCPH_FLAGS(tcphdr) >> 3 & 1,
|
||
TCPH_FLAGS(tcphdr) >> 2 & 1,
|
||
TCPH_FLAGS(tcphdr) >> 1 & 1,
|
||
TCPH_FLAGS(tcphdr) & 1,
|
||
ntohs(tcphdr->wnd)));
|
||
tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("), win)\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("| 0x%04"X16_F" | %5"U16_F" | (chksum, urgp)\n",
|
||
ntohs(tcphdr->chksum), ntohs(tcphdr->urgp)));
|
||
LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
|
||
}
|
||
|
||
/**
|
||
* Print a tcp state for debugging purposes.
|
||
*
|
||
* @param s enum tcp_state to print
|
||
*/
|
||
void
|
||
tcp_debug_print_state(enum tcp_state s)
|
||
{
|
||
LWIP_DEBUGF(TCP_DEBUG, ("State: %s\n", tcp_state_str[s]));
|
||
}
|
||
|
||
/**
|
||
* Print tcp flags for debugging purposes.
|
||
*
|
||
* @param flags tcp flags, all active flags are printed
|
||
*/
|
||
void
|
||
tcp_debug_print_flags(u8_t flags)
|
||
{
|
||
if (flags & TCP_FIN) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("FIN "));
|
||
}
|
||
if (flags & TCP_SYN) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("SYN "));
|
||
}
|
||
if (flags & TCP_RST) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("RST "));
|
||
}
|
||
if (flags & TCP_PSH) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("PSH "));
|
||
}
|
||
if (flags & TCP_ACK) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("ACK "));
|
||
}
|
||
if (flags & TCP_URG) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("URG "));
|
||
}
|
||
if (flags & TCP_ECE) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("ECE "));
|
||
}
|
||
if (flags & TCP_CWR) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("CWR "));
|
||
}
|
||
LWIP_DEBUGF(TCP_DEBUG, ("\n"));
|
||
}
|
||
|
||
/**
|
||
* Print all tcp_pcbs in every list for debugging purposes.
|
||
*/
|
||
void
|
||
tcp_debug_print_pcbs(void)
|
||
{
|
||
struct tcp_pcb *pcb;
|
||
LWIP_DEBUGF(TCP_DEBUG, ("Active PCB states:\n"));
|
||
for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
|
||
pcb->local_port, pcb->remote_port,
|
||
pcb->snd_nxt, pcb->rcv_nxt));
|
||
tcp_debug_print_state(pcb->state);
|
||
}
|
||
LWIP_DEBUGF(TCP_DEBUG, ("Listen PCB states:\n"));
|
||
for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
|
||
pcb->local_port, pcb->remote_port,
|
||
pcb->snd_nxt, pcb->rcv_nxt));
|
||
tcp_debug_print_state(pcb->state);
|
||
}
|
||
LWIP_DEBUGF(TCP_DEBUG, ("TIME-WAIT PCB states:\n"));
|
||
for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
|
||
LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
|
||
pcb->local_port, pcb->remote_port,
|
||
pcb->snd_nxt, pcb->rcv_nxt));
|
||
tcp_debug_print_state(pcb->state);
|
||
}
|
||
}
|
||
|
||
/**
|
||
* Check state consistency of the tcp_pcb lists.
|
||
*/
|
||
s16_t
|
||
tcp_pcbs_sane(void)
|
||
{
|
||
struct tcp_pcb *pcb;
|
||
for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
|
||
LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != CLOSED", pcb->state != CLOSED);
|
||
LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != LISTEN", pcb->state != LISTEN);
|
||
LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
|
||
}
|
||
for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
|
||
LWIP_ASSERT("tcp_pcbs_sane: tw pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
|
||
}
|
||
return 1;
|
||
}
|
||
#endif /* TCP_DEBUG */
|
||
|
||
#endif /* LWIP_TCP */
|