Wayne Jay / EthernetInterface

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Dependents:   K64F_eCompass_OneNET_JW

lwip/core/tcp.c@0:b2805b6888dc, 2016-06-20 (annotated)

Committer:
robert_jw
Date:
Mon Jun 20 01:40:20 2016 +0000
Revision:
0:b2805b6888dc
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Who changed what in which revision?

UserRevisionLine numberNew contents of line
robert_jw 0:b2805b6888dc 1 /**
robert_jw 0:b2805b6888dc 2 * @file
robert_jw 0:b2805b6888dc 3 * Transmission Control Protocol for IP
robert_jw 0:b2805b6888dc 4 *
robert_jw 0:b2805b6888dc 5 * This file contains common functions for the TCP implementation, such as functinos
robert_jw 0:b2805b6888dc 6 * for manipulating the data structures and the TCP timer functions. TCP functions
robert_jw 0:b2805b6888dc 7 * related to input and output is found in tcp_in.c and tcp_out.c respectively.
robert_jw 0:b2805b6888dc 8 *
robert_jw 0:b2805b6888dc 9 */
robert_jw 0:b2805b6888dc 10
robert_jw 0:b2805b6888dc 11 /*
robert_jw 0:b2805b6888dc 12 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
robert_jw 0:b2805b6888dc 13 * All rights reserved.
robert_jw 0:b2805b6888dc 14 *
robert_jw 0:b2805b6888dc 15 * Redistribution and use in source and binary forms, with or without modification,
robert_jw 0:b2805b6888dc 16 * are permitted provided that the following conditions are met:
robert_jw 0:b2805b6888dc 17 *
robert_jw 0:b2805b6888dc 18 * 1. Redistributions of source code must retain the above copyright notice,
robert_jw 0:b2805b6888dc 19 * this list of conditions and the following disclaimer.
robert_jw 0:b2805b6888dc 20 * 2. Redistributions in binary form must reproduce the above copyright notice,
robert_jw 0:b2805b6888dc 21 * this list of conditions and the following disclaimer in the documentation
robert_jw 0:b2805b6888dc 22 * and/or other materials provided with the distribution.
robert_jw 0:b2805b6888dc 23 * 3. The name of the author may not be used to endorse or promote products
robert_jw 0:b2805b6888dc 24 * derived from this software without specific prior written permission.
robert_jw 0:b2805b6888dc 25 *
robert_jw 0:b2805b6888dc 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
robert_jw 0:b2805b6888dc 27 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
robert_jw 0:b2805b6888dc 28 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
robert_jw 0:b2805b6888dc 29 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
robert_jw 0:b2805b6888dc 30 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
robert_jw 0:b2805b6888dc 31 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
robert_jw 0:b2805b6888dc 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
robert_jw 0:b2805b6888dc 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
robert_jw 0:b2805b6888dc 34 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
robert_jw 0:b2805b6888dc 35 * OF SUCH DAMAGE.
robert_jw 0:b2805b6888dc 36 *
robert_jw 0:b2805b6888dc 37 * This file is part of the lwIP TCP/IP stack.
robert_jw 0:b2805b6888dc 38 *
robert_jw 0:b2805b6888dc 39 * Author: Adam Dunkels <adam@sics.se>
robert_jw 0:b2805b6888dc 40 *
robert_jw 0:b2805b6888dc 41 */
robert_jw 0:b2805b6888dc 42
robert_jw 0:b2805b6888dc 43 #include "lwip/opt.h"
robert_jw 0:b2805b6888dc 44
robert_jw 0:b2805b6888dc 45 #if LWIP_TCP /* don't build if not configured for use in lwipopts.h */
robert_jw 0:b2805b6888dc 46
robert_jw 0:b2805b6888dc 47 #include "lwip/def.h"
robert_jw 0:b2805b6888dc 48 #include "lwip/mem.h"
robert_jw 0:b2805b6888dc 49 #include "lwip/memp.h"
robert_jw 0:b2805b6888dc 50 #include "lwip/snmp.h"
robert_jw 0:b2805b6888dc 51 #include "lwip/tcp.h"
robert_jw 0:b2805b6888dc 52 #include "lwip/tcp_impl.h"
robert_jw 0:b2805b6888dc 53 #include "lwip/debug.h"
robert_jw 0:b2805b6888dc 54 #include "lwip/stats.h"
robert_jw 0:b2805b6888dc 55
robert_jw 0:b2805b6888dc 56 #include <string.h>
robert_jw 0:b2805b6888dc 57
robert_jw 0:b2805b6888dc 58 const char * const tcp_state_str[] = {
robert_jw 0:b2805b6888dc 59 "CLOSED",
robert_jw 0:b2805b6888dc 60 "LISTEN",
robert_jw 0:b2805b6888dc 61 "SYN_SENT",
robert_jw 0:b2805b6888dc 62 "SYN_RCVD",
robert_jw 0:b2805b6888dc 63 "ESTABLISHED",
robert_jw 0:b2805b6888dc 64 "FIN_WAIT_1",
robert_jw 0:b2805b6888dc 65 "FIN_WAIT_2",
robert_jw 0:b2805b6888dc 66 "CLOSE_WAIT",
robert_jw 0:b2805b6888dc 67 "CLOSING",
robert_jw 0:b2805b6888dc 68 "LAST_ACK",
robert_jw 0:b2805b6888dc 69 "TIME_WAIT"
robert_jw 0:b2805b6888dc 70 };
robert_jw 0:b2805b6888dc 71
robert_jw 0:b2805b6888dc 72 /* Incremented every coarse grained timer shot (typically every 500 ms). */
robert_jw 0:b2805b6888dc 73 u32_t tcp_ticks;
robert_jw 0:b2805b6888dc 74 const u8_t tcp_backoff[13] =
robert_jw 0:b2805b6888dc 75 { 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7};
robert_jw 0:b2805b6888dc 76 /* Times per slowtmr hits */
robert_jw 0:b2805b6888dc 77 const u8_t tcp_persist_backoff[7] = { 3, 6, 12, 24, 48, 96, 120 };
robert_jw 0:b2805b6888dc 78
robert_jw 0:b2805b6888dc 79 /* The TCP PCB lists. */
robert_jw 0:b2805b6888dc 80
robert_jw 0:b2805b6888dc 81 /** List of all TCP PCBs bound but not yet (connected || listening) */
robert_jw 0:b2805b6888dc 82 struct tcp_pcb *tcp_bound_pcbs;
robert_jw 0:b2805b6888dc 83 /** List of all TCP PCBs in LISTEN state */
robert_jw 0:b2805b6888dc 84 union tcp_listen_pcbs_t tcp_listen_pcbs;
robert_jw 0:b2805b6888dc 85 /** List of all TCP PCBs that are in a state in which
robert_jw 0:b2805b6888dc 86 * they accept or send data. */
robert_jw 0:b2805b6888dc 87 struct tcp_pcb *tcp_active_pcbs;
robert_jw 0:b2805b6888dc 88 /** List of all TCP PCBs in TIME-WAIT state */
robert_jw 0:b2805b6888dc 89 struct tcp_pcb *tcp_tw_pcbs;
robert_jw 0:b2805b6888dc 90
robert_jw 0:b2805b6888dc 91 #define NUM_TCP_PCB_LISTS 4
robert_jw 0:b2805b6888dc 92 #define NUM_TCP_PCB_LISTS_NO_TIME_WAIT 3
robert_jw 0:b2805b6888dc 93 /** An array with all (non-temporary) PCB lists, mainly used for smaller code size */
robert_jw 0:b2805b6888dc 94 struct tcp_pcb ** const tcp_pcb_lists[] = {&tcp_listen_pcbs.pcbs, &tcp_bound_pcbs,
robert_jw 0:b2805b6888dc 95 &tcp_active_pcbs, &tcp_tw_pcbs};
robert_jw 0:b2805b6888dc 96
robert_jw 0:b2805b6888dc 97 /** Only used for temporary storage. */
robert_jw 0:b2805b6888dc 98 struct tcp_pcb *tcp_tmp_pcb;
robert_jw 0:b2805b6888dc 99
robert_jw 0:b2805b6888dc 100 /** Timer counter to handle calling slow-timer from tcp_tmr() */
robert_jw 0:b2805b6888dc 101 static u8_t tcp_timer;
robert_jw 0:b2805b6888dc 102 static u16_t tcp_new_port(void);
robert_jw 0:b2805b6888dc 103
robert_jw 0:b2805b6888dc 104 /**
robert_jw 0:b2805b6888dc 105 * Called periodically to dispatch TCP timers.
robert_jw 0:b2805b6888dc 106 *
robert_jw 0:b2805b6888dc 107 */
robert_jw 0:b2805b6888dc 108 void
robert_jw 0:b2805b6888dc 109 tcp_tmr(void)
robert_jw 0:b2805b6888dc 110 {
robert_jw 0:b2805b6888dc 111 /* Call tcp_fasttmr() every 250 ms */
robert_jw 0:b2805b6888dc 112 tcp_fasttmr();
robert_jw 0:b2805b6888dc 113
robert_jw 0:b2805b6888dc 114 if (++tcp_timer & 1) {
robert_jw 0:b2805b6888dc 115 /* Call tcp_tmr() every 500 ms, i.e., every other timer
robert_jw 0:b2805b6888dc 116 tcp_tmr() is called. */
robert_jw 0:b2805b6888dc 117 tcp_slowtmr();
robert_jw 0:b2805b6888dc 118 }
robert_jw 0:b2805b6888dc 119 }
robert_jw 0:b2805b6888dc 120
robert_jw 0:b2805b6888dc 121 /**
robert_jw 0:b2805b6888dc 122 * Closes the TX side of a connection held by the PCB.
robert_jw 0:b2805b6888dc 123 * For tcp_close(), a RST is sent if the application didn't receive all data
robert_jw 0:b2805b6888dc 124 * (tcp_recved() not called for all data passed to recv callback).
robert_jw 0:b2805b6888dc 125 *
robert_jw 0:b2805b6888dc 126 * Listening pcbs are freed and may not be referenced any more.
robert_jw 0:b2805b6888dc 127 * Connection pcbs are freed if not yet connected and may not be referenced
robert_jw 0:b2805b6888dc 128 * any more. If a connection is established (at least SYN received or in
robert_jw 0:b2805b6888dc 129 * a closing state), the connection is closed, and put in a closing state.
robert_jw 0:b2805b6888dc 130 * The pcb is then automatically freed in tcp_slowtmr(). It is therefore
robert_jw 0:b2805b6888dc 131 * unsafe to reference it.
robert_jw 0:b2805b6888dc 132 *
robert_jw 0:b2805b6888dc 133 * @param pcb the tcp_pcb to close
robert_jw 0:b2805b6888dc 134 * @return ERR_OK if connection has been closed
robert_jw 0:b2805b6888dc 135 * another err_t if closing failed and pcb is not freed
robert_jw 0:b2805b6888dc 136 */
robert_jw 0:b2805b6888dc 137 static err_t
robert_jw 0:b2805b6888dc 138 tcp_close_shutdown(struct tcp_pcb *pcb, u8_t rst_on_unacked_data)
robert_jw 0:b2805b6888dc 139 {
robert_jw 0:b2805b6888dc 140 err_t err;
robert_jw 0:b2805b6888dc 141
robert_jw 0:b2805b6888dc 142 if (rst_on_unacked_data && (pcb->state != LISTEN)) {
robert_jw 0:b2805b6888dc 143 if ((pcb->refused_data != NULL) || (pcb->rcv_wnd != TCP_WND)) {
robert_jw 0:b2805b6888dc 144 /* Not all data received by application, send RST to tell the remote
robert_jw 0:b2805b6888dc 145 side about this. */
robert_jw 0:b2805b6888dc 146 LWIP_ASSERT("pcb->flags & TF_RXCLOSED", pcb->flags & TF_RXCLOSED);
robert_jw 0:b2805b6888dc 147
robert_jw 0:b2805b6888dc 148 /* don't call tcp_abort here: we must not deallocate the pcb since
robert_jw 0:b2805b6888dc 149 that might not be expected when calling tcp_close */
robert_jw 0:b2805b6888dc 150 tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
robert_jw 0:b2805b6888dc 151 pcb->local_port, pcb->remote_port);
robert_jw 0:b2805b6888dc 152
robert_jw 0:b2805b6888dc 153 tcp_pcb_purge(pcb);
robert_jw 0:b2805b6888dc 154
robert_jw 0:b2805b6888dc 155 /* TODO: to which state do we move now? */
robert_jw 0:b2805b6888dc 156
robert_jw 0:b2805b6888dc 157 /* move to TIME_WAIT since we close actively */
robert_jw 0:b2805b6888dc 158 TCP_RMV(&tcp_active_pcbs, pcb);
robert_jw 0:b2805b6888dc 159 pcb->state = TIME_WAIT;
robert_jw 0:b2805b6888dc 160 TCP_REG(&tcp_tw_pcbs, pcb);
robert_jw 0:b2805b6888dc 161
robert_jw 0:b2805b6888dc 162 return ERR_OK;
robert_jw 0:b2805b6888dc 163 }
robert_jw 0:b2805b6888dc 164 }
robert_jw 0:b2805b6888dc 165
robert_jw 0:b2805b6888dc 166 switch (pcb->state) {
robert_jw 0:b2805b6888dc 167 case CLOSED:
robert_jw 0:b2805b6888dc 168 /* Closing a pcb in the CLOSED state might seem erroneous,
robert_jw 0:b2805b6888dc 169 * however, it is in this state once allocated and as yet unused
robert_jw 0:b2805b6888dc 170 * and the user needs some way to free it should the need arise.
robert_jw 0:b2805b6888dc 171 * Calling tcp_close() with a pcb that has already been closed, (i.e. twice)
robert_jw 0:b2805b6888dc 172 * or for a pcb that has been used and then entered the CLOSED state
robert_jw 0:b2805b6888dc 173 * is erroneous, but this should never happen as the pcb has in those cases
robert_jw 0:b2805b6888dc 174 * been freed, and so any remaining handles are bogus. */
robert_jw 0:b2805b6888dc 175 err = ERR_OK;
robert_jw 0:b2805b6888dc 176 if (pcb->local_port != 0) {
robert_jw 0:b2805b6888dc 177 TCP_RMV(&tcp_bound_pcbs, pcb);
robert_jw 0:b2805b6888dc 178 }
robert_jw 0:b2805b6888dc 179 memp_free(MEMP_TCP_PCB, pcb);
robert_jw 0:b2805b6888dc 180 pcb = NULL;
robert_jw 0:b2805b6888dc 181 break;
robert_jw 0:b2805b6888dc 182 case LISTEN:
robert_jw 0:b2805b6888dc 183 err = ERR_OK;
robert_jw 0:b2805b6888dc 184 tcp_pcb_remove(&tcp_listen_pcbs.pcbs, pcb);
robert_jw 0:b2805b6888dc 185 memp_free(MEMP_TCP_PCB_LISTEN, pcb);
robert_jw 0:b2805b6888dc 186 pcb = NULL;
robert_jw 0:b2805b6888dc 187 break;
robert_jw 0:b2805b6888dc 188 case SYN_SENT:
robert_jw 0:b2805b6888dc 189 err = ERR_OK;
robert_jw 0:b2805b6888dc 190 tcp_pcb_remove(&tcp_active_pcbs, pcb);
robert_jw 0:b2805b6888dc 191 memp_free(MEMP_TCP_PCB, pcb);
robert_jw 0:b2805b6888dc 192 pcb = NULL;
robert_jw 0:b2805b6888dc 193 snmp_inc_tcpattemptfails();
robert_jw 0:b2805b6888dc 194 break;
robert_jw 0:b2805b6888dc 195 case SYN_RCVD:
robert_jw 0:b2805b6888dc 196 err = tcp_send_fin(pcb);
robert_jw 0:b2805b6888dc 197 if (err == ERR_OK) {
robert_jw 0:b2805b6888dc 198 snmp_inc_tcpattemptfails();
robert_jw 0:b2805b6888dc 199 pcb->state = FIN_WAIT_1;
robert_jw 0:b2805b6888dc 200 }
robert_jw 0:b2805b6888dc 201 break;
robert_jw 0:b2805b6888dc 202 case ESTABLISHED:
robert_jw 0:b2805b6888dc 203 err = tcp_send_fin(pcb);
robert_jw 0:b2805b6888dc 204 if (err == ERR_OK) {
robert_jw 0:b2805b6888dc 205 snmp_inc_tcpestabresets();
robert_jw 0:b2805b6888dc 206 pcb->state = FIN_WAIT_1;
robert_jw 0:b2805b6888dc 207 }
robert_jw 0:b2805b6888dc 208 break;
robert_jw 0:b2805b6888dc 209 case CLOSE_WAIT:
robert_jw 0:b2805b6888dc 210 err = tcp_send_fin(pcb);
robert_jw 0:b2805b6888dc 211 if (err == ERR_OK) {
robert_jw 0:b2805b6888dc 212 snmp_inc_tcpestabresets();
robert_jw 0:b2805b6888dc 213 pcb->state = LAST_ACK;
robert_jw 0:b2805b6888dc 214 }
robert_jw 0:b2805b6888dc 215 break;
robert_jw 0:b2805b6888dc 216 default:
robert_jw 0:b2805b6888dc 217 /* Has already been closed, do nothing. */
robert_jw 0:b2805b6888dc 218 err = ERR_OK;
robert_jw 0:b2805b6888dc 219 pcb = NULL;
robert_jw 0:b2805b6888dc 220 break;
robert_jw 0:b2805b6888dc 221 }
robert_jw 0:b2805b6888dc 222
robert_jw 0:b2805b6888dc 223 if (pcb != NULL && err == ERR_OK) {
robert_jw 0:b2805b6888dc 224 /* To ensure all data has been sent when tcp_close returns, we have
robert_jw 0:b2805b6888dc 225 to make sure tcp_output doesn't fail.
robert_jw 0:b2805b6888dc 226 Since we don't really have to ensure all data has been sent when tcp_close
robert_jw 0:b2805b6888dc 227 returns (unsent data is sent from tcp timer functions, also), we don't care
robert_jw 0:b2805b6888dc 228 for the return value of tcp_output for now. */
robert_jw 0:b2805b6888dc 229 /* @todo: When implementing SO_LINGER, this must be changed somehow:
robert_jw 0:b2805b6888dc 230 If SOF_LINGER is set, the data should be sent and acked before close returns.
robert_jw 0:b2805b6888dc 231 This can only be valid for sequential APIs, not for the raw API. */
robert_jw 0:b2805b6888dc 232 tcp_output(pcb);
robert_jw 0:b2805b6888dc 233 }
robert_jw 0:b2805b6888dc 234 return err;
robert_jw 0:b2805b6888dc 235 }
robert_jw 0:b2805b6888dc 236
robert_jw 0:b2805b6888dc 237 /**
robert_jw 0:b2805b6888dc 238 * Closes the connection held by the PCB.
robert_jw 0:b2805b6888dc 239 *
robert_jw 0:b2805b6888dc 240 * Listening pcbs are freed and may not be referenced any more.
robert_jw 0:b2805b6888dc 241 * Connection pcbs are freed if not yet connected and may not be referenced
robert_jw 0:b2805b6888dc 242 * any more. If a connection is established (at least SYN received or in
robert_jw 0:b2805b6888dc 243 * a closing state), the connection is closed, and put in a closing state.
robert_jw 0:b2805b6888dc 244 * The pcb is then automatically freed in tcp_slowtmr(). It is therefore
robert_jw 0:b2805b6888dc 245 * unsafe to reference it (unless an error is returned).
robert_jw 0:b2805b6888dc 246 *
robert_jw 0:b2805b6888dc 247 * @param pcb the tcp_pcb to close
robert_jw 0:b2805b6888dc 248 * @return ERR_OK if connection has been closed
robert_jw 0:b2805b6888dc 249 * another err_t if closing failed and pcb is not freed
robert_jw 0:b2805b6888dc 250 */
robert_jw 0:b2805b6888dc 251 err_t
robert_jw 0:b2805b6888dc 252 tcp_close(struct tcp_pcb *pcb)
robert_jw 0:b2805b6888dc 253 {
robert_jw 0:b2805b6888dc 254 #if TCP_DEBUG
robert_jw 0:b2805b6888dc 255 LWIP_DEBUGF(TCP_DEBUG, ("tcp_close: closing in "));
robert_jw 0:b2805b6888dc 256 tcp_debug_print_state(pcb->state);
robert_jw 0:b2805b6888dc 257 #endif /* TCP_DEBUG */
robert_jw 0:b2805b6888dc 258
robert_jw 0:b2805b6888dc 259 if (pcb->state != LISTEN) {
robert_jw 0:b2805b6888dc 260 /* Set a flag not to receive any more data... */
robert_jw 0:b2805b6888dc 261 pcb->flags |= TF_RXCLOSED;
robert_jw 0:b2805b6888dc 262 }
robert_jw 0:b2805b6888dc 263 /* ... and close */
robert_jw 0:b2805b6888dc 264 return tcp_close_shutdown(pcb, 1);
robert_jw 0:b2805b6888dc 265 }
robert_jw 0:b2805b6888dc 266
robert_jw 0:b2805b6888dc 267 /**
robert_jw 0:b2805b6888dc 268 * Causes all or part of a full-duplex connection of this PCB to be shut down.
robert_jw 0:b2805b6888dc 269 * This doesn't deallocate the PCB!
robert_jw 0:b2805b6888dc 270 *
robert_jw 0:b2805b6888dc 271 * @param pcb PCB to shutdown
robert_jw 0:b2805b6888dc 272 * @param shut_rx shut down receive side if this is != 0
robert_jw 0:b2805b6888dc 273 * @param shut_tx shut down send side if this is != 0
robert_jw 0:b2805b6888dc 274 * @return ERR_OK if shutdown succeeded (or the PCB has already been shut down)
robert_jw 0:b2805b6888dc 275 * another err_t on error.
robert_jw 0:b2805b6888dc 276 */
robert_jw 0:b2805b6888dc 277 err_t
robert_jw 0:b2805b6888dc 278 tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx)
robert_jw 0:b2805b6888dc 279 {
robert_jw 0:b2805b6888dc 280 if (pcb->state == LISTEN) {
robert_jw 0:b2805b6888dc 281 return ERR_CONN;
robert_jw 0:b2805b6888dc 282 }
robert_jw 0:b2805b6888dc 283 if (shut_rx) {
robert_jw 0:b2805b6888dc 284 /* shut down the receive side: free buffered data... */
robert_jw 0:b2805b6888dc 285 if (pcb->refused_data != NULL) {
robert_jw 0:b2805b6888dc 286 pbuf_free(pcb->refused_data);
robert_jw 0:b2805b6888dc 287 pcb->refused_data = NULL;
robert_jw 0:b2805b6888dc 288 }
robert_jw 0:b2805b6888dc 289 /* ... and set a flag not to receive any more data */
robert_jw 0:b2805b6888dc 290 pcb->flags |= TF_RXCLOSED;
robert_jw 0:b2805b6888dc 291 }
robert_jw 0:b2805b6888dc 292 if (shut_tx) {
robert_jw 0:b2805b6888dc 293 /* This can't happen twice since if it succeeds, the pcb's state is changed.
robert_jw 0:b2805b6888dc 294 Only close in these states as the others directly deallocate the PCB */
robert_jw 0:b2805b6888dc 295 switch (pcb->state) {
robert_jw 0:b2805b6888dc 296 case SYN_RCVD:
robert_jw 0:b2805b6888dc 297 case ESTABLISHED:
robert_jw 0:b2805b6888dc 298 case CLOSE_WAIT:
robert_jw 0:b2805b6888dc 299 return tcp_close_shutdown(pcb, 0);
robert_jw 0:b2805b6888dc 300 default:
robert_jw 0:b2805b6888dc 301 /* don't shut down other states */
robert_jw 0:b2805b6888dc 302 break;
robert_jw 0:b2805b6888dc 303 }
robert_jw 0:b2805b6888dc 304 }
robert_jw 0:b2805b6888dc 305 /* @todo: return another err_t if not in correct state or already shut? */
robert_jw 0:b2805b6888dc 306 return ERR_OK;
robert_jw 0:b2805b6888dc 307 }
robert_jw 0:b2805b6888dc 308
robert_jw 0:b2805b6888dc 309 /**
robert_jw 0:b2805b6888dc 310 * Abandons a connection and optionally sends a RST to the remote
robert_jw 0:b2805b6888dc 311 * host. Deletes the local protocol control block. This is done when
robert_jw 0:b2805b6888dc 312 * a connection is killed because of shortage of memory.
robert_jw 0:b2805b6888dc 313 *
robert_jw 0:b2805b6888dc 314 * @param pcb the tcp_pcb to abort
robert_jw 0:b2805b6888dc 315 * @param reset boolean to indicate whether a reset should be sent
robert_jw 0:b2805b6888dc 316 */
robert_jw 0:b2805b6888dc 317 void
robert_jw 0:b2805b6888dc 318 tcp_abandon(struct tcp_pcb *pcb, int reset)
robert_jw 0:b2805b6888dc 319 {
robert_jw 0:b2805b6888dc 320 u32_t seqno, ackno;
robert_jw 0:b2805b6888dc 321 u16_t remote_port, local_port;
robert_jw 0:b2805b6888dc 322 ip_addr_t remote_ip, local_ip;
robert_jw 0:b2805b6888dc 323 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 324 tcp_err_fn errf;
robert_jw 0:b2805b6888dc 325 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 326 void *errf_arg;
robert_jw 0:b2805b6888dc 327
robert_jw 0:b2805b6888dc 328 /* pcb->state LISTEN not allowed here */
robert_jw 0:b2805b6888dc 329 LWIP_ASSERT("don't call tcp_abort/tcp_abandon for listen-pcbs",
robert_jw 0:b2805b6888dc 330 pcb->state != LISTEN);
robert_jw 0:b2805b6888dc 331 /* Figure out on which TCP PCB list we are, and remove us. If we
robert_jw 0:b2805b6888dc 332 are in an active state, call the receive function associated with
robert_jw 0:b2805b6888dc 333 the PCB with a NULL argument, and send an RST to the remote end. */
robert_jw 0:b2805b6888dc 334 if (pcb->state == TIME_WAIT) {
robert_jw 0:b2805b6888dc 335 tcp_pcb_remove(&tcp_tw_pcbs, pcb);
robert_jw 0:b2805b6888dc 336 memp_free(MEMP_TCP_PCB, pcb);
robert_jw 0:b2805b6888dc 337 } else {
robert_jw 0:b2805b6888dc 338 seqno = pcb->snd_nxt;
robert_jw 0:b2805b6888dc 339 ackno = pcb->rcv_nxt;
robert_jw 0:b2805b6888dc 340 ip_addr_copy(local_ip, pcb->local_ip);
robert_jw 0:b2805b6888dc 341 ip_addr_copy(remote_ip, pcb->remote_ip);
robert_jw 0:b2805b6888dc 342 local_port = pcb->local_port;
robert_jw 0:b2805b6888dc 343 remote_port = pcb->remote_port;
robert_jw 0:b2805b6888dc 344 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 345 errf = pcb->errf;
robert_jw 0:b2805b6888dc 346 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 347 errf_arg = pcb->callback_arg;
robert_jw 0:b2805b6888dc 348 tcp_pcb_remove(&tcp_active_pcbs, pcb);
robert_jw 0:b2805b6888dc 349 if (pcb->unacked != NULL) {
robert_jw 0:b2805b6888dc 350 tcp_segs_free(pcb->unacked);
robert_jw 0:b2805b6888dc 351 }
robert_jw 0:b2805b6888dc 352 if (pcb->unsent != NULL) {
robert_jw 0:b2805b6888dc 353 tcp_segs_free(pcb->unsent);
robert_jw 0:b2805b6888dc 354 }
robert_jw 0:b2805b6888dc 355 #if TCP_QUEUE_OOSEQ
robert_jw 0:b2805b6888dc 356 if (pcb->ooseq != NULL) {
robert_jw 0:b2805b6888dc 357 tcp_segs_free(pcb->ooseq);
robert_jw 0:b2805b6888dc 358 }
robert_jw 0:b2805b6888dc 359 #endif /* TCP_QUEUE_OOSEQ */
robert_jw 0:b2805b6888dc 360 memp_free(MEMP_TCP_PCB, pcb);
robert_jw 0:b2805b6888dc 361 TCP_EVENT_ERR(errf, errf_arg, ERR_ABRT);
robert_jw 0:b2805b6888dc 362 if (reset) {
robert_jw 0:b2805b6888dc 363 LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_abandon: sending RST\n"));
robert_jw 0:b2805b6888dc 364 tcp_rst(seqno, ackno, &local_ip, &remote_ip, local_port, remote_port);
robert_jw 0:b2805b6888dc 365 }
robert_jw 0:b2805b6888dc 366 }
robert_jw 0:b2805b6888dc 367 }
robert_jw 0:b2805b6888dc 368
robert_jw 0:b2805b6888dc 369 /**
robert_jw 0:b2805b6888dc 370 * Aborts the connection by sending a RST (reset) segment to the remote
robert_jw 0:b2805b6888dc 371 * host. The pcb is deallocated. This function never fails.
robert_jw 0:b2805b6888dc 372 *
robert_jw 0:b2805b6888dc 373 * ATTENTION: When calling this from one of the TCP callbacks, make
robert_jw 0:b2805b6888dc 374 * sure you always return ERR_ABRT (and never return ERR_ABRT otherwise
robert_jw 0:b2805b6888dc 375 * or you will risk accessing deallocated memory or memory leaks!
robert_jw 0:b2805b6888dc 376 *
robert_jw 0:b2805b6888dc 377 * @param pcb the tcp pcb to abort
robert_jw 0:b2805b6888dc 378 */
robert_jw 0:b2805b6888dc 379 void
robert_jw 0:b2805b6888dc 380 tcp_abort(struct tcp_pcb *pcb)
robert_jw 0:b2805b6888dc 381 {
robert_jw 0:b2805b6888dc 382 tcp_abandon(pcb, 1);
robert_jw 0:b2805b6888dc 383 }
robert_jw 0:b2805b6888dc 384
robert_jw 0:b2805b6888dc 385 /**
robert_jw 0:b2805b6888dc 386 * Binds the connection to a local portnumber and IP address. If the
robert_jw 0:b2805b6888dc 387 * IP address is not given (i.e., ipaddr == NULL), the IP address of
robert_jw 0:b2805b6888dc 388 * the outgoing network interface is used instead.
robert_jw 0:b2805b6888dc 389 *
robert_jw 0:b2805b6888dc 390 * @param pcb the tcp_pcb to bind (no check is done whether this pcb is
robert_jw 0:b2805b6888dc 391 * already bound!)
robert_jw 0:b2805b6888dc 392 * @param ipaddr the local ip address to bind to (use IP_ADDR_ANY to bind
robert_jw 0:b2805b6888dc 393 * to any local address
robert_jw 0:b2805b6888dc 394 * @param port the local port to bind to
robert_jw 0:b2805b6888dc 395 * @return ERR_USE if the port is already in use
robert_jw 0:b2805b6888dc 396 * ERR_VAL if bind failed because the PCB is not in a valid state
robert_jw 0:b2805b6888dc 397 * ERR_OK if bound
robert_jw 0:b2805b6888dc 398 */
robert_jw 0:b2805b6888dc 399 err_t
robert_jw 0:b2805b6888dc 400 tcp_bind(struct tcp_pcb *pcb, ip_addr_t *ipaddr, u16_t port)
robert_jw 0:b2805b6888dc 401 {
robert_jw 0:b2805b6888dc 402 int i;
robert_jw 0:b2805b6888dc 403 int max_pcb_list = NUM_TCP_PCB_LISTS;
robert_jw 0:b2805b6888dc 404 struct tcp_pcb *cpcb;
robert_jw 0:b2805b6888dc 405
robert_jw 0:b2805b6888dc 406 LWIP_ERROR("tcp_bind: can only bind in state CLOSED", pcb->state == CLOSED, return ERR_VAL);
robert_jw 0:b2805b6888dc 407
robert_jw 0:b2805b6888dc 408 #if SO_REUSE
robert_jw 0:b2805b6888dc 409 /* Unless the REUSEADDR flag is set,
robert_jw 0:b2805b6888dc 410 we have to check the pcbs in TIME-WAIT state, also.
robert_jw 0:b2805b6888dc 411 We do not dump TIME_WAIT pcb's; they can still be matched by incoming
robert_jw 0:b2805b6888dc 412 packets using both local and remote IP addresses and ports to distinguish.
robert_jw 0:b2805b6888dc 413 */
robert_jw 0:b2805b6888dc 414 if ((pcb->so_options & SOF_REUSEADDR) != 0) {
robert_jw 0:b2805b6888dc 415 max_pcb_list = NUM_TCP_PCB_LISTS_NO_TIME_WAIT;
robert_jw 0:b2805b6888dc 416 }
robert_jw 0:b2805b6888dc 417 #endif /* SO_REUSE */
robert_jw 0:b2805b6888dc 418
robert_jw 0:b2805b6888dc 419 if (port == 0) {
robert_jw 0:b2805b6888dc 420 port = tcp_new_port();
robert_jw 0:b2805b6888dc 421 }
robert_jw 0:b2805b6888dc 422
robert_jw 0:b2805b6888dc 423 /* Check if the address already is in use (on all lists) */
robert_jw 0:b2805b6888dc 424 for (i = 0; i < max_pcb_list; i++) {
robert_jw 0:b2805b6888dc 425 for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
robert_jw 0:b2805b6888dc 426 if (cpcb->local_port == port) {
robert_jw 0:b2805b6888dc 427 #if SO_REUSE
robert_jw 0:b2805b6888dc 428 /* Omit checking for the same port if both pcbs have REUSEADDR set.
robert_jw 0:b2805b6888dc 429 For SO_REUSEADDR, the duplicate-check for a 5-tuple is done in
robert_jw 0:b2805b6888dc 430 tcp_connect. */
robert_jw 0:b2805b6888dc 431 if (((pcb->so_options & SOF_REUSEADDR) == 0) ||
robert_jw 0:b2805b6888dc 432 ((cpcb->so_options & SOF_REUSEADDR) == 0))
robert_jw 0:b2805b6888dc 433 #endif /* SO_REUSE */
robert_jw 0:b2805b6888dc 434 {
robert_jw 0:b2805b6888dc 435 if (ip_addr_isany(&(cpcb->local_ip)) ||
robert_jw 0:b2805b6888dc 436 ip_addr_isany(ipaddr) ||
robert_jw 0:b2805b6888dc 437 ip_addr_cmp(&(cpcb->local_ip), ipaddr)) {
robert_jw 0:b2805b6888dc 438 return ERR_USE;
robert_jw 0:b2805b6888dc 439 }
robert_jw 0:b2805b6888dc 440 }
robert_jw 0:b2805b6888dc 441 }
robert_jw 0:b2805b6888dc 442 }
robert_jw 0:b2805b6888dc 443 }
robert_jw 0:b2805b6888dc 444
robert_jw 0:b2805b6888dc 445 if (!ip_addr_isany(ipaddr)) {
robert_jw 0:b2805b6888dc 446 pcb->local_ip = *ipaddr;
robert_jw 0:b2805b6888dc 447 }
robert_jw 0:b2805b6888dc 448 pcb->local_port = port;
robert_jw 0:b2805b6888dc 449 TCP_REG(&tcp_bound_pcbs, pcb);
robert_jw 0:b2805b6888dc 450 LWIP_DEBUGF(TCP_DEBUG, ("tcp_bind: bind to port %"U16_F"\n", port));
robert_jw 0:b2805b6888dc 451 return ERR_OK;
robert_jw 0:b2805b6888dc 452 }
robert_jw 0:b2805b6888dc 453 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 454 /**
robert_jw 0:b2805b6888dc 455 * Default accept callback if no accept callback is specified by the user.
robert_jw 0:b2805b6888dc 456 */
robert_jw 0:b2805b6888dc 457 static err_t
robert_jw 0:b2805b6888dc 458 tcp_accept_null(void *arg, struct tcp_pcb *pcb, err_t err)
robert_jw 0:b2805b6888dc 459 {
robert_jw 0:b2805b6888dc 460 LWIP_UNUSED_ARG(arg);
robert_jw 0:b2805b6888dc 461 LWIP_UNUSED_ARG(pcb);
robert_jw 0:b2805b6888dc 462 LWIP_UNUSED_ARG(err);
robert_jw 0:b2805b6888dc 463
robert_jw 0:b2805b6888dc 464 return ERR_ABRT;
robert_jw 0:b2805b6888dc 465 }
robert_jw 0:b2805b6888dc 466 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 467
robert_jw 0:b2805b6888dc 468 /**
robert_jw 0:b2805b6888dc 469 * Set the state of the connection to be LISTEN, which means that it
robert_jw 0:b2805b6888dc 470 * is able to accept incoming connections. The protocol control block
robert_jw 0:b2805b6888dc 471 * is reallocated in order to consume less memory. Setting the
robert_jw 0:b2805b6888dc 472 * connection to LISTEN is an irreversible process.
robert_jw 0:b2805b6888dc 473 *
robert_jw 0:b2805b6888dc 474 * @param pcb the original tcp_pcb
robert_jw 0:b2805b6888dc 475 * @param backlog the incoming connections queue limit
robert_jw 0:b2805b6888dc 476 * @return tcp_pcb used for listening, consumes less memory.
robert_jw 0:b2805b6888dc 477 *
robert_jw 0:b2805b6888dc 478 * @note The original tcp_pcb is freed. This function therefore has to be
robert_jw 0:b2805b6888dc 479 * called like this:
robert_jw 0:b2805b6888dc 480 * tpcb = tcp_listen(tpcb);
robert_jw 0:b2805b6888dc 481 */
robert_jw 0:b2805b6888dc 482 struct tcp_pcb *
robert_jw 0:b2805b6888dc 483 tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog)
robert_jw 0:b2805b6888dc 484 {
robert_jw 0:b2805b6888dc 485 struct tcp_pcb_listen *lpcb;
robert_jw 0:b2805b6888dc 486
robert_jw 0:b2805b6888dc 487 LWIP_UNUSED_ARG(backlog);
robert_jw 0:b2805b6888dc 488 LWIP_ERROR("tcp_listen: pcb already connected", pcb->state == CLOSED, return NULL);
robert_jw 0:b2805b6888dc 489
robert_jw 0:b2805b6888dc 490 /* already listening? */
robert_jw 0:b2805b6888dc 491 if (pcb->state == LISTEN) {
robert_jw 0:b2805b6888dc 492 return pcb;
robert_jw 0:b2805b6888dc 493 }
robert_jw 0:b2805b6888dc 494 #if SO_REUSE
robert_jw 0:b2805b6888dc 495 if ((pcb->so_options & SOF_REUSEADDR) != 0) {
robert_jw 0:b2805b6888dc 496 /* Since SOF_REUSEADDR allows reusing a local address before the pcb's usage
robert_jw 0:b2805b6888dc 497 is declared (listen-/connection-pcb), we have to make sure now that
robert_jw 0:b2805b6888dc 498 this port is only used once for every local IP. */
robert_jw 0:b2805b6888dc 499 for(lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
robert_jw 0:b2805b6888dc 500 if (lpcb->local_port == pcb->local_port) {
robert_jw 0:b2805b6888dc 501 if (ip_addr_cmp(&lpcb->local_ip, &pcb->local_ip)) {
robert_jw 0:b2805b6888dc 502 /* this address/port is already used */
robert_jw 0:b2805b6888dc 503 return NULL;
robert_jw 0:b2805b6888dc 504 }
robert_jw 0:b2805b6888dc 505 }
robert_jw 0:b2805b6888dc 506 }
robert_jw 0:b2805b6888dc 507 }
robert_jw 0:b2805b6888dc 508 #endif /* SO_REUSE */
robert_jw 0:b2805b6888dc 509 lpcb = (struct tcp_pcb_listen *)memp_malloc(MEMP_TCP_PCB_LISTEN);
robert_jw 0:b2805b6888dc 510 if (lpcb == NULL) {
robert_jw 0:b2805b6888dc 511 return NULL;
robert_jw 0:b2805b6888dc 512 }
robert_jw 0:b2805b6888dc 513 lpcb->callback_arg = pcb->callback_arg;
robert_jw 0:b2805b6888dc 514 lpcb->local_port = pcb->local_port;
robert_jw 0:b2805b6888dc 515 lpcb->state = LISTEN;
robert_jw 0:b2805b6888dc 516 lpcb->prio = pcb->prio;
robert_jw 0:b2805b6888dc 517 lpcb->so_options = pcb->so_options;
robert_jw 0:b2805b6888dc 518 lpcb->so_options |= SOF_ACCEPTCONN;
robert_jw 0:b2805b6888dc 519 lpcb->ttl = pcb->ttl;
robert_jw 0:b2805b6888dc 520 lpcb->tos = pcb->tos;
robert_jw 0:b2805b6888dc 521 ip_addr_copy(lpcb->local_ip, pcb->local_ip);
robert_jw 0:b2805b6888dc 522 if (pcb->local_port != 0) {
robert_jw 0:b2805b6888dc 523 TCP_RMV(&tcp_bound_pcbs, pcb);
robert_jw 0:b2805b6888dc 524 }
robert_jw 0:b2805b6888dc 525 memp_free(MEMP_TCP_PCB, pcb);
robert_jw 0:b2805b6888dc 526 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 527 lpcb->accept = tcp_accept_null;
robert_jw 0:b2805b6888dc 528 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 529 #if TCP_LISTEN_BACKLOG
robert_jw 0:b2805b6888dc 530 lpcb->accepts_pending = 0;
robert_jw 0:b2805b6888dc 531 lpcb->backlog = (backlog ? backlog : 1);
robert_jw 0:b2805b6888dc 532 #endif /* TCP_LISTEN_BACKLOG */
robert_jw 0:b2805b6888dc 533 TCP_REG(&tcp_listen_pcbs.pcbs, (struct tcp_pcb *)lpcb);
robert_jw 0:b2805b6888dc 534 return (struct tcp_pcb *)lpcb;
robert_jw 0:b2805b6888dc 535 }
robert_jw 0:b2805b6888dc 536
robert_jw 0:b2805b6888dc 537 /**
robert_jw 0:b2805b6888dc 538 * Update the state that tracks the available window space to advertise.
robert_jw 0:b2805b6888dc 539 *
robert_jw 0:b2805b6888dc 540 * Returns how much extra window would be advertised if we sent an
robert_jw 0:b2805b6888dc 541 * update now.
robert_jw 0:b2805b6888dc 542 */
robert_jw 0:b2805b6888dc 543 u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb)
robert_jw 0:b2805b6888dc 544 {
robert_jw 0:b2805b6888dc 545 u32_t new_right_edge = pcb->rcv_nxt + pcb->rcv_wnd;
robert_jw 0:b2805b6888dc 546
robert_jw 0:b2805b6888dc 547 if (TCP_SEQ_GEQ(new_right_edge, pcb->rcv_ann_right_edge + LWIP_MIN((TCP_WND / 2), pcb->mss))) {
robert_jw 0:b2805b6888dc 548 /* we can advertise more window */
robert_jw 0:b2805b6888dc 549 pcb->rcv_ann_wnd = pcb->rcv_wnd;
robert_jw 0:b2805b6888dc 550 return new_right_edge - pcb->rcv_ann_right_edge;
robert_jw 0:b2805b6888dc 551 } else {
robert_jw 0:b2805b6888dc 552 if (TCP_SEQ_GT(pcb->rcv_nxt, pcb->rcv_ann_right_edge)) {
robert_jw 0:b2805b6888dc 553 /* Can happen due to other end sending out of advertised window,
robert_jw 0:b2805b6888dc 554 * but within actual available (but not yet advertised) window */
robert_jw 0:b2805b6888dc 555 pcb->rcv_ann_wnd = 0;
robert_jw 0:b2805b6888dc 556 } else {
robert_jw 0:b2805b6888dc 557 /* keep the right edge of window constant */
robert_jw 0:b2805b6888dc 558 u32_t new_rcv_ann_wnd = pcb->rcv_ann_right_edge - pcb->rcv_nxt;
robert_jw 0:b2805b6888dc 559 LWIP_ASSERT("new_rcv_ann_wnd <= 0xffff", new_rcv_ann_wnd <= 0xffff);
robert_jw 0:b2805b6888dc 560 pcb->rcv_ann_wnd = (u16_t)new_rcv_ann_wnd;
robert_jw 0:b2805b6888dc 561 }
robert_jw 0:b2805b6888dc 562 return 0;
robert_jw 0:b2805b6888dc 563 }
robert_jw 0:b2805b6888dc 564 }
robert_jw 0:b2805b6888dc 565
robert_jw 0:b2805b6888dc 566 /**
robert_jw 0:b2805b6888dc 567 * This function should be called by the application when it has
robert_jw 0:b2805b6888dc 568 * processed the data. The purpose is to advertise a larger window
robert_jw 0:b2805b6888dc 569 * when the data has been processed.
robert_jw 0:b2805b6888dc 570 *
robert_jw 0:b2805b6888dc 571 * @param pcb the tcp_pcb for which data is read
robert_jw 0:b2805b6888dc 572 * @param len the amount of bytes that have been read by the application
robert_jw 0:b2805b6888dc 573 */
robert_jw 0:b2805b6888dc 574 void
robert_jw 0:b2805b6888dc 575 tcp_recved(struct tcp_pcb *pcb, u16_t len)
robert_jw 0:b2805b6888dc 576 {
robert_jw 0:b2805b6888dc 577 int wnd_inflation;
robert_jw 0:b2805b6888dc 578
robert_jw 0:b2805b6888dc 579 LWIP_ASSERT("tcp_recved: len would wrap rcv_wnd\n",
robert_jw 0:b2805b6888dc 580 len <= 0xffff - pcb->rcv_wnd );
robert_jw 0:b2805b6888dc 581
robert_jw 0:b2805b6888dc 582 pcb->rcv_wnd += len;
robert_jw 0:b2805b6888dc 583 if (pcb->rcv_wnd > TCP_WND) {
robert_jw 0:b2805b6888dc 584 pcb->rcv_wnd = TCP_WND;
robert_jw 0:b2805b6888dc 585 }
robert_jw 0:b2805b6888dc 586
robert_jw 0:b2805b6888dc 587 wnd_inflation = tcp_update_rcv_ann_wnd(pcb);
robert_jw 0:b2805b6888dc 588
robert_jw 0:b2805b6888dc 589 /* If the change in the right edge of window is significant (default
robert_jw 0:b2805b6888dc 590 * watermark is TCP_WND/4), then send an explicit update now.
robert_jw 0:b2805b6888dc 591 * Otherwise wait for a packet to be sent in the normal course of
robert_jw 0:b2805b6888dc 592 * events (or more window to be available later) */
robert_jw 0:b2805b6888dc 593 if (wnd_inflation >= TCP_WND_UPDATE_THRESHOLD) {
robert_jw 0:b2805b6888dc 594 tcp_ack_now(pcb);
robert_jw 0:b2805b6888dc 595 tcp_output(pcb);
robert_jw 0:b2805b6888dc 596 }
robert_jw 0:b2805b6888dc 597
robert_jw 0:b2805b6888dc 598 LWIP_DEBUGF(TCP_DEBUG, ("tcp_recved: recveived %"U16_F" bytes, wnd %"U16_F" (%"U16_F").\n",
robert_jw 0:b2805b6888dc 599 len, pcb->rcv_wnd, TCP_WND - pcb->rcv_wnd));
robert_jw 0:b2805b6888dc 600 }
robert_jw 0:b2805b6888dc 601
robert_jw 0:b2805b6888dc 602 /**
robert_jw 0:b2805b6888dc 603 * A nastly hack featuring 'goto' statements that allocates a
robert_jw 0:b2805b6888dc 604 * new TCP local port.
robert_jw 0:b2805b6888dc 605 *
robert_jw 0:b2805b6888dc 606 * @return a new (free) local TCP port number
robert_jw 0:b2805b6888dc 607 */
robert_jw 0:b2805b6888dc 608 static u16_t
robert_jw 0:b2805b6888dc 609 tcp_new_port(void)
robert_jw 0:b2805b6888dc 610 {
robert_jw 0:b2805b6888dc 611 int i;
robert_jw 0:b2805b6888dc 612 struct tcp_pcb *pcb;
robert_jw 0:b2805b6888dc 613 #ifndef TCP_LOCAL_PORT_RANGE_START
robert_jw 0:b2805b6888dc 614 /* From http://www.iana.org/assignments/port-numbers:
robert_jw 0:b2805b6888dc 615 "The Dynamic and/or Private Ports are those from 49152 through 65535" */
robert_jw 0:b2805b6888dc 616 #define TCP_LOCAL_PORT_RANGE_START 0xc000
robert_jw 0:b2805b6888dc 617 #define TCP_LOCAL_PORT_RANGE_END 0xffff
robert_jw 0:b2805b6888dc 618 #endif
robert_jw 0:b2805b6888dc 619 static u16_t port = TCP_LOCAL_PORT_RANGE_START;
robert_jw 0:b2805b6888dc 620
robert_jw 0:b2805b6888dc 621 again:
robert_jw 0:b2805b6888dc 622 if (port++ >= TCP_LOCAL_PORT_RANGE_END) {
robert_jw 0:b2805b6888dc 623 port = TCP_LOCAL_PORT_RANGE_START;
robert_jw 0:b2805b6888dc 624 }
robert_jw 0:b2805b6888dc 625 /* Check all PCB lists. */
robert_jw 0:b2805b6888dc 626 for (i = 0; i < NUM_TCP_PCB_LISTS; i++) {
robert_jw 0:b2805b6888dc 627 for(pcb = *tcp_pcb_lists[i]; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 628 if (pcb->local_port == port) {
robert_jw 0:b2805b6888dc 629 goto again;
robert_jw 0:b2805b6888dc 630 }
robert_jw 0:b2805b6888dc 631 }
robert_jw 0:b2805b6888dc 632 }
robert_jw 0:b2805b6888dc 633 return port;
robert_jw 0:b2805b6888dc 634 }
robert_jw 0:b2805b6888dc 635
robert_jw 0:b2805b6888dc 636 /**
robert_jw 0:b2805b6888dc 637 * Connects to another host. The function given as the "connected"
robert_jw 0:b2805b6888dc 638 * argument will be called when the connection has been established.
robert_jw 0:b2805b6888dc 639 *
robert_jw 0:b2805b6888dc 640 * @param pcb the tcp_pcb used to establish the connection
robert_jw 0:b2805b6888dc 641 * @param ipaddr the remote ip address to connect to
robert_jw 0:b2805b6888dc 642 * @param port the remote tcp port to connect to
robert_jw 0:b2805b6888dc 643 * @param connected callback function to call when connected (or on error)
robert_jw 0:b2805b6888dc 644 * @return ERR_VAL if invalid arguments are given
robert_jw 0:b2805b6888dc 645 * ERR_OK if connect request has been sent
robert_jw 0:b2805b6888dc 646 * other err_t values if connect request couldn't be sent
robert_jw 0:b2805b6888dc 647 */
robert_jw 0:b2805b6888dc 648 err_t
robert_jw 0:b2805b6888dc 649 tcp_connect(struct tcp_pcb *pcb, ip_addr_t *ipaddr, u16_t port,
robert_jw 0:b2805b6888dc 650 tcp_connected_fn connected)
robert_jw 0:b2805b6888dc 651 {
robert_jw 0:b2805b6888dc 652 err_t ret;
robert_jw 0:b2805b6888dc 653 u32_t iss;
robert_jw 0:b2805b6888dc 654 u16_t old_local_port;
robert_jw 0:b2805b6888dc 655
robert_jw 0:b2805b6888dc 656 LWIP_ERROR("tcp_connect: can only connect from state CLOSED", pcb->state == CLOSED, return ERR_ISCONN);
robert_jw 0:b2805b6888dc 657
robert_jw 0:b2805b6888dc 658 LWIP_DEBUGF(TCP_DEBUG, ("tcp_connect to port %"U16_F"\n", port));
robert_jw 0:b2805b6888dc 659 if (ipaddr != NULL) {
robert_jw 0:b2805b6888dc 660 pcb->remote_ip = *ipaddr;
robert_jw 0:b2805b6888dc 661 } else {
robert_jw 0:b2805b6888dc 662 return ERR_VAL;
robert_jw 0:b2805b6888dc 663 }
robert_jw 0:b2805b6888dc 664 pcb->remote_port = port;
robert_jw 0:b2805b6888dc 665
robert_jw 0:b2805b6888dc 666 /* check if we have a route to the remote host */
robert_jw 0:b2805b6888dc 667 if (ip_addr_isany(&(pcb->local_ip))) {
robert_jw 0:b2805b6888dc 668 /* no local IP address set, yet. */
robert_jw 0:b2805b6888dc 669 struct netif *netif = ip_route(&(pcb->remote_ip));
robert_jw 0:b2805b6888dc 670 if (netif == NULL) {
robert_jw 0:b2805b6888dc 671 /* Don't even try to send a SYN packet if we have no route
robert_jw 0:b2805b6888dc 672 since that will fail. */
robert_jw 0:b2805b6888dc 673 return ERR_RTE;
robert_jw 0:b2805b6888dc 674 }
robert_jw 0:b2805b6888dc 675 /* Use the netif's IP address as local address. */
robert_jw 0:b2805b6888dc 676 ip_addr_copy(pcb->local_ip, netif->ip_addr);
robert_jw 0:b2805b6888dc 677 }
robert_jw 0:b2805b6888dc 678
robert_jw 0:b2805b6888dc 679 old_local_port = pcb->local_port;
robert_jw 0:b2805b6888dc 680 if (pcb->local_port == 0) {
robert_jw 0:b2805b6888dc 681 pcb->local_port = tcp_new_port();
robert_jw 0:b2805b6888dc 682 }
robert_jw 0:b2805b6888dc 683 #if SO_REUSE
robert_jw 0:b2805b6888dc 684 if ((pcb->so_options & SOF_REUSEADDR) != 0) {
robert_jw 0:b2805b6888dc 685 /* Since SOF_REUSEADDR allows reusing a local address, we have to make sure
robert_jw 0:b2805b6888dc 686 now that the 5-tuple is unique. */
robert_jw 0:b2805b6888dc 687 struct tcp_pcb *cpcb;
robert_jw 0:b2805b6888dc 688 int i;
robert_jw 0:b2805b6888dc 689 /* Don't check listen- and bound-PCBs, check active- and TIME-WAIT PCBs. */
robert_jw 0:b2805b6888dc 690 for (i = 2; i < NUM_TCP_PCB_LISTS; i++) {
robert_jw 0:b2805b6888dc 691 for(cpcb = *tcp_pcb_lists[i]; cpcb != NULL; cpcb = cpcb->next) {
robert_jw 0:b2805b6888dc 692 if ((cpcb->local_port == pcb->local_port) &&
robert_jw 0:b2805b6888dc 693 (cpcb->remote_port == port) &&
robert_jw 0:b2805b6888dc 694 ip_addr_cmp(&cpcb->local_ip, &pcb->local_ip) &&
robert_jw 0:b2805b6888dc 695 ip_addr_cmp(&cpcb->remote_ip, ipaddr)) {
robert_jw 0:b2805b6888dc 696 /* linux returns EISCONN here, but ERR_USE should be OK for us */
robert_jw 0:b2805b6888dc 697 return ERR_USE;
robert_jw 0:b2805b6888dc 698 }
robert_jw 0:b2805b6888dc 699 }
robert_jw 0:b2805b6888dc 700 }
robert_jw 0:b2805b6888dc 701 }
robert_jw 0:b2805b6888dc 702 #endif /* SO_REUSE */
robert_jw 0:b2805b6888dc 703 iss = tcp_next_iss();
robert_jw 0:b2805b6888dc 704 pcb->rcv_nxt = 0;
robert_jw 0:b2805b6888dc 705 pcb->snd_nxt = iss;
robert_jw 0:b2805b6888dc 706 pcb->lastack = iss - 1;
robert_jw 0:b2805b6888dc 707 pcb->snd_lbb = iss - 1;
robert_jw 0:b2805b6888dc 708 pcb->rcv_wnd = TCP_WND;
robert_jw 0:b2805b6888dc 709 pcb->rcv_ann_wnd = TCP_WND;
robert_jw 0:b2805b6888dc 710 pcb->rcv_ann_right_edge = pcb->rcv_nxt;
robert_jw 0:b2805b6888dc 711 pcb->snd_wnd = TCP_WND;
robert_jw 0:b2805b6888dc 712 /* As initial send MSS, we use TCP_MSS but limit it to 536.
robert_jw 0:b2805b6888dc 713 The send MSS is updated when an MSS option is received. */
robert_jw 0:b2805b6888dc 714 pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
robert_jw 0:b2805b6888dc 715 #if TCP_CALCULATE_EFF_SEND_MSS
robert_jw 0:b2805b6888dc 716 pcb->mss = tcp_eff_send_mss(pcb->mss, ipaddr);
robert_jw 0:b2805b6888dc 717 #endif /* TCP_CALCULATE_EFF_SEND_MSS */
robert_jw 0:b2805b6888dc 718 pcb->cwnd = 1;
robert_jw 0:b2805b6888dc 719 pcb->ssthresh = pcb->mss * 10;
robert_jw 0:b2805b6888dc 720 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 721 pcb->connected = connected;
robert_jw 0:b2805b6888dc 722 #else /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 723 LWIP_UNUSED_ARG(connected);
robert_jw 0:b2805b6888dc 724 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 725
robert_jw 0:b2805b6888dc 726 /* Send a SYN together with the MSS option. */
robert_jw 0:b2805b6888dc 727 ret = tcp_enqueue_flags(pcb, TCP_SYN);
robert_jw 0:b2805b6888dc 728 if (ret == ERR_OK) {
robert_jw 0:b2805b6888dc 729 /* SYN segment was enqueued, changed the pcbs state now */
robert_jw 0:b2805b6888dc 730 pcb->state = SYN_SENT;
robert_jw 0:b2805b6888dc 731 if (old_local_port != 0) {
robert_jw 0:b2805b6888dc 732 TCP_RMV(&tcp_bound_pcbs, pcb);
robert_jw 0:b2805b6888dc 733 }
robert_jw 0:b2805b6888dc 734 TCP_REG(&tcp_active_pcbs, pcb);
robert_jw 0:b2805b6888dc 735 snmp_inc_tcpactiveopens();
robert_jw 0:b2805b6888dc 736
robert_jw 0:b2805b6888dc 737 tcp_output(pcb);
robert_jw 0:b2805b6888dc 738 }
robert_jw 0:b2805b6888dc 739 return ret;
robert_jw 0:b2805b6888dc 740 }
robert_jw 0:b2805b6888dc 741
robert_jw 0:b2805b6888dc 742 /**
robert_jw 0:b2805b6888dc 743 * Called every 500 ms and implements the retransmission timer and the timer that
robert_jw 0:b2805b6888dc 744 * removes PCBs that have been in TIME-WAIT for enough time. It also increments
robert_jw 0:b2805b6888dc 745 * various timers such as the inactivity timer in each PCB.
robert_jw 0:b2805b6888dc 746 *
robert_jw 0:b2805b6888dc 747 * Automatically called from tcp_tmr().
robert_jw 0:b2805b6888dc 748 */
robert_jw 0:b2805b6888dc 749 void
robert_jw 0:b2805b6888dc 750 tcp_slowtmr(void)
robert_jw 0:b2805b6888dc 751 {
robert_jw 0:b2805b6888dc 752 struct tcp_pcb *pcb, *prev;
robert_jw 0:b2805b6888dc 753 u16_t eff_wnd;
robert_jw 0:b2805b6888dc 754 u8_t pcb_remove; /* flag if a PCB should be removed */
robert_jw 0:b2805b6888dc 755 u8_t pcb_reset; /* flag if a RST should be sent when removing */
robert_jw 0:b2805b6888dc 756 err_t err;
robert_jw 0:b2805b6888dc 757
robert_jw 0:b2805b6888dc 758 err = ERR_OK;
robert_jw 0:b2805b6888dc 759
robert_jw 0:b2805b6888dc 760 ++tcp_ticks;
robert_jw 0:b2805b6888dc 761
robert_jw 0:b2805b6888dc 762 /* Steps through all of the active PCBs. */
robert_jw 0:b2805b6888dc 763 prev = NULL;
robert_jw 0:b2805b6888dc 764 pcb = tcp_active_pcbs;
robert_jw 0:b2805b6888dc 765 if (pcb == NULL) {
robert_jw 0:b2805b6888dc 766 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: no active pcbs\n"));
robert_jw 0:b2805b6888dc 767 }
robert_jw 0:b2805b6888dc 768 while (pcb != NULL) {
robert_jw 0:b2805b6888dc 769 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: processing active pcb\n"));
robert_jw 0:b2805b6888dc 770 LWIP_ASSERT("tcp_slowtmr: active pcb->state != CLOSED\n", pcb->state != CLOSED);
robert_jw 0:b2805b6888dc 771 LWIP_ASSERT("tcp_slowtmr: active pcb->state != LISTEN\n", pcb->state != LISTEN);
robert_jw 0:b2805b6888dc 772 LWIP_ASSERT("tcp_slowtmr: active pcb->state != TIME-WAIT\n", pcb->state != TIME_WAIT);
robert_jw 0:b2805b6888dc 773
robert_jw 0:b2805b6888dc 774 pcb_remove = 0;
robert_jw 0:b2805b6888dc 775 pcb_reset = 0;
robert_jw 0:b2805b6888dc 776
robert_jw 0:b2805b6888dc 777 if (pcb->state == SYN_SENT && pcb->nrtx == TCP_SYNMAXRTX) {
robert_jw 0:b2805b6888dc 778 ++pcb_remove;
robert_jw 0:b2805b6888dc 779 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max SYN retries reached\n"));
robert_jw 0:b2805b6888dc 780 }
robert_jw 0:b2805b6888dc 781 else if (pcb->nrtx == TCP_MAXRTX) {
robert_jw 0:b2805b6888dc 782 ++pcb_remove;
robert_jw 0:b2805b6888dc 783 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: max DATA retries reached\n"));
robert_jw 0:b2805b6888dc 784 } else {
robert_jw 0:b2805b6888dc 785 if (pcb->persist_backoff > 0) {
robert_jw 0:b2805b6888dc 786 /* If snd_wnd is zero, use persist timer to send 1 byte probes
robert_jw 0:b2805b6888dc 787 * instead of using the standard retransmission mechanism. */
robert_jw 0:b2805b6888dc 788 pcb->persist_cnt++;
robert_jw 0:b2805b6888dc 789 if (pcb->persist_cnt >= tcp_persist_backoff[pcb->persist_backoff-1]) {
robert_jw 0:b2805b6888dc 790 pcb->persist_cnt = 0;
robert_jw 0:b2805b6888dc 791 if (pcb->persist_backoff < sizeof(tcp_persist_backoff)) {
robert_jw 0:b2805b6888dc 792 pcb->persist_backoff++;
robert_jw 0:b2805b6888dc 793 }
robert_jw 0:b2805b6888dc 794 tcp_zero_window_probe(pcb);
robert_jw 0:b2805b6888dc 795 }
robert_jw 0:b2805b6888dc 796 } else {
robert_jw 0:b2805b6888dc 797 /* Increase the retransmission timer if it is running */
robert_jw 0:b2805b6888dc 798 if(pcb->rtime >= 0)
robert_jw 0:b2805b6888dc 799 ++pcb->rtime;
robert_jw 0:b2805b6888dc 800
robert_jw 0:b2805b6888dc 801 if (pcb->unacked != NULL && pcb->rtime >= pcb->rto) {
robert_jw 0:b2805b6888dc 802 /* Time for a retransmission. */
robert_jw 0:b2805b6888dc 803 LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_slowtmr: rtime %"S16_F
robert_jw 0:b2805b6888dc 804 " pcb->rto %"S16_F"\n",
robert_jw 0:b2805b6888dc 805 pcb->rtime, pcb->rto));
robert_jw 0:b2805b6888dc 806
robert_jw 0:b2805b6888dc 807 /* Double retransmission time-out unless we are trying to
robert_jw 0:b2805b6888dc 808 * connect to somebody (i.e., we are in SYN_SENT). */
robert_jw 0:b2805b6888dc 809 if (pcb->state != SYN_SENT) {
robert_jw 0:b2805b6888dc 810 pcb->rto = ((pcb->sa >> 3) + pcb->sv) << tcp_backoff[pcb->nrtx];
robert_jw 0:b2805b6888dc 811 }
robert_jw 0:b2805b6888dc 812
robert_jw 0:b2805b6888dc 813 /* Reset the retransmission timer. */
robert_jw 0:b2805b6888dc 814 pcb->rtime = 0;
robert_jw 0:b2805b6888dc 815
robert_jw 0:b2805b6888dc 816 /* Reduce congestion window and ssthresh. */
robert_jw 0:b2805b6888dc 817 eff_wnd = LWIP_MIN(pcb->cwnd, pcb->snd_wnd);
robert_jw 0:b2805b6888dc 818 pcb->ssthresh = eff_wnd >> 1;
robert_jw 0:b2805b6888dc 819 if (pcb->ssthresh < (pcb->mss << 1)) {
robert_jw 0:b2805b6888dc 820 pcb->ssthresh = (pcb->mss << 1);
robert_jw 0:b2805b6888dc 821 }
robert_jw 0:b2805b6888dc 822 pcb->cwnd = pcb->mss;
robert_jw 0:b2805b6888dc 823 LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: cwnd %"U16_F
robert_jw 0:b2805b6888dc 824 " ssthresh %"U16_F"\n",
robert_jw 0:b2805b6888dc 825 pcb->cwnd, pcb->ssthresh));
robert_jw 0:b2805b6888dc 826
robert_jw 0:b2805b6888dc 827 /* The following needs to be called AFTER cwnd is set to one
robert_jw 0:b2805b6888dc 828 mss - STJ */
robert_jw 0:b2805b6888dc 829 tcp_rexmit_rto(pcb);
robert_jw 0:b2805b6888dc 830 }
robert_jw 0:b2805b6888dc 831 }
robert_jw 0:b2805b6888dc 832 }
robert_jw 0:b2805b6888dc 833 /* Check if this PCB has stayed too long in FIN-WAIT-2 */
robert_jw 0:b2805b6888dc 834 if (pcb->state == FIN_WAIT_2) {
robert_jw 0:b2805b6888dc 835 if ((u32_t)(tcp_ticks - pcb->tmr) >
robert_jw 0:b2805b6888dc 836 TCP_FIN_WAIT_TIMEOUT / TCP_SLOW_INTERVAL) {
robert_jw 0:b2805b6888dc 837 ++pcb_remove;
robert_jw 0:b2805b6888dc 838 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in FIN-WAIT-2\n"));
robert_jw 0:b2805b6888dc 839 }
robert_jw 0:b2805b6888dc 840 }
robert_jw 0:b2805b6888dc 841
robert_jw 0:b2805b6888dc 842 /* Check if KEEPALIVE should be sent */
robert_jw 0:b2805b6888dc 843 if((pcb->so_options & SOF_KEEPALIVE) &&
robert_jw 0:b2805b6888dc 844 ((pcb->state == ESTABLISHED) ||
robert_jw 0:b2805b6888dc 845 (pcb->state == CLOSE_WAIT))) {
robert_jw 0:b2805b6888dc 846 #if LWIP_TCP_KEEPALIVE
robert_jw 0:b2805b6888dc 847 if((u32_t)(tcp_ticks - pcb->tmr) >
robert_jw 0:b2805b6888dc 848 (pcb->keep_idle + (pcb->keep_cnt*pcb->keep_intvl))
robert_jw 0:b2805b6888dc 849 / TCP_SLOW_INTERVAL)
robert_jw 0:b2805b6888dc 850 #else
robert_jw 0:b2805b6888dc 851 if((u32_t)(tcp_ticks - pcb->tmr) >
robert_jw 0:b2805b6888dc 852 (pcb->keep_idle + TCP_MAXIDLE) / TCP_SLOW_INTERVAL)
robert_jw 0:b2805b6888dc 853 #endif /* LWIP_TCP_KEEPALIVE */
robert_jw 0:b2805b6888dc 854 {
robert_jw 0:b2805b6888dc 855 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: KEEPALIVE timeout. Aborting connection to %"U16_F".%"U16_F".%"U16_F".%"U16_F".\n",
robert_jw 0:b2805b6888dc 856 ip4_addr1_16(&pcb->remote_ip), ip4_addr2_16(&pcb->remote_ip),
robert_jw 0:b2805b6888dc 857 ip4_addr3_16(&pcb->remote_ip), ip4_addr4_16(&pcb->remote_ip)));
robert_jw 0:b2805b6888dc 858
robert_jw 0:b2805b6888dc 859 ++pcb_remove;
robert_jw 0:b2805b6888dc 860 ++pcb_reset;
robert_jw 0:b2805b6888dc 861 }
robert_jw 0:b2805b6888dc 862 #if LWIP_TCP_KEEPALIVE
robert_jw 0:b2805b6888dc 863 else if((u32_t)(tcp_ticks - pcb->tmr) >
robert_jw 0:b2805b6888dc 864 (pcb->keep_idle + pcb->keep_cnt_sent * pcb->keep_intvl)
robert_jw 0:b2805b6888dc 865 / TCP_SLOW_INTERVAL)
robert_jw 0:b2805b6888dc 866 #else
robert_jw 0:b2805b6888dc 867 else if((u32_t)(tcp_ticks - pcb->tmr) >
robert_jw 0:b2805b6888dc 868 (pcb->keep_idle + pcb->keep_cnt_sent * TCP_KEEPINTVL_DEFAULT)
robert_jw 0:b2805b6888dc 869 / TCP_SLOW_INTERVAL)
robert_jw 0:b2805b6888dc 870 #endif /* LWIP_TCP_KEEPALIVE */
robert_jw 0:b2805b6888dc 871 {
robert_jw 0:b2805b6888dc 872 tcp_keepalive(pcb);
robert_jw 0:b2805b6888dc 873 pcb->keep_cnt_sent++;
robert_jw 0:b2805b6888dc 874 }
robert_jw 0:b2805b6888dc 875 }
robert_jw 0:b2805b6888dc 876
robert_jw 0:b2805b6888dc 877 /* If this PCB has queued out of sequence data, but has been
robert_jw 0:b2805b6888dc 878 inactive for too long, will drop the data (it will eventually
robert_jw 0:b2805b6888dc 879 be retransmitted). */
robert_jw 0:b2805b6888dc 880 #if TCP_QUEUE_OOSEQ
robert_jw 0:b2805b6888dc 881 if (pcb->ooseq != NULL &&
robert_jw 0:b2805b6888dc 882 (u32_t)tcp_ticks - pcb->tmr >= pcb->rto * TCP_OOSEQ_TIMEOUT) {
robert_jw 0:b2805b6888dc 883 tcp_segs_free(pcb->ooseq);
robert_jw 0:b2805b6888dc 884 pcb->ooseq = NULL;
robert_jw 0:b2805b6888dc 885 LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_slowtmr: dropping OOSEQ queued data\n"));
robert_jw 0:b2805b6888dc 886 }
robert_jw 0:b2805b6888dc 887 #endif /* TCP_QUEUE_OOSEQ */
robert_jw 0:b2805b6888dc 888
robert_jw 0:b2805b6888dc 889 /* Check if this PCB has stayed too long in SYN-RCVD */
robert_jw 0:b2805b6888dc 890 if (pcb->state == SYN_RCVD) {
robert_jw 0:b2805b6888dc 891 if ((u32_t)(tcp_ticks - pcb->tmr) >
robert_jw 0:b2805b6888dc 892 TCP_SYN_RCVD_TIMEOUT / TCP_SLOW_INTERVAL) {
robert_jw 0:b2805b6888dc 893 ++pcb_remove;
robert_jw 0:b2805b6888dc 894 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in SYN-RCVD\n"));
robert_jw 0:b2805b6888dc 895 }
robert_jw 0:b2805b6888dc 896 }
robert_jw 0:b2805b6888dc 897
robert_jw 0:b2805b6888dc 898 /* Check if this PCB has stayed too long in LAST-ACK */
robert_jw 0:b2805b6888dc 899 if (pcb->state == LAST_ACK) {
robert_jw 0:b2805b6888dc 900 if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
robert_jw 0:b2805b6888dc 901 ++pcb_remove;
robert_jw 0:b2805b6888dc 902 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: removing pcb stuck in LAST-ACK\n"));
robert_jw 0:b2805b6888dc 903 }
robert_jw 0:b2805b6888dc 904 }
robert_jw 0:b2805b6888dc 905
robert_jw 0:b2805b6888dc 906 /* If the PCB should be removed, do it. */
robert_jw 0:b2805b6888dc 907 if (pcb_remove) {
robert_jw 0:b2805b6888dc 908 struct tcp_pcb *pcb2;
robert_jw 0:b2805b6888dc 909 tcp_pcb_purge(pcb);
robert_jw 0:b2805b6888dc 910 /* Remove PCB from tcp_active_pcbs list. */
robert_jw 0:b2805b6888dc 911 if (prev != NULL) {
robert_jw 0:b2805b6888dc 912 LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_active_pcbs", pcb != tcp_active_pcbs);
robert_jw 0:b2805b6888dc 913 prev->next = pcb->next;
robert_jw 0:b2805b6888dc 914 } else {
robert_jw 0:b2805b6888dc 915 /* This PCB was the first. */
robert_jw 0:b2805b6888dc 916 LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_active_pcbs", tcp_active_pcbs == pcb);
robert_jw 0:b2805b6888dc 917 tcp_active_pcbs = pcb->next;
robert_jw 0:b2805b6888dc 918 }
robert_jw 0:b2805b6888dc 919
robert_jw 0:b2805b6888dc 920 TCP_EVENT_ERR(pcb->errf, pcb->callback_arg, ERR_ABRT);
robert_jw 0:b2805b6888dc 921 if (pcb_reset) {
robert_jw 0:b2805b6888dc 922 tcp_rst(pcb->snd_nxt, pcb->rcv_nxt, &pcb->local_ip, &pcb->remote_ip,
robert_jw 0:b2805b6888dc 923 pcb->local_port, pcb->remote_port);
robert_jw 0:b2805b6888dc 924 }
robert_jw 0:b2805b6888dc 925
robert_jw 0:b2805b6888dc 926 pcb2 = pcb;
robert_jw 0:b2805b6888dc 927 pcb = pcb->next;
robert_jw 0:b2805b6888dc 928 memp_free(MEMP_TCP_PCB, pcb2);
robert_jw 0:b2805b6888dc 929 } else {
robert_jw 0:b2805b6888dc 930 /* get the 'next' element now and work with 'prev' below (in case of abort) */
robert_jw 0:b2805b6888dc 931 prev = pcb;
robert_jw 0:b2805b6888dc 932 pcb = pcb->next;
robert_jw 0:b2805b6888dc 933
robert_jw 0:b2805b6888dc 934 /* We check if we should poll the connection. */
robert_jw 0:b2805b6888dc 935 ++prev->polltmr;
robert_jw 0:b2805b6888dc 936 if (prev->polltmr >= prev->pollinterval) {
robert_jw 0:b2805b6888dc 937 prev->polltmr = 0;
robert_jw 0:b2805b6888dc 938 LWIP_DEBUGF(TCP_DEBUG, ("tcp_slowtmr: polling application\n"));
robert_jw 0:b2805b6888dc 939 TCP_EVENT_POLL(prev, err);
robert_jw 0:b2805b6888dc 940 /* if err == ERR_ABRT, 'prev' is already deallocated */
robert_jw 0:b2805b6888dc 941 if (err == ERR_OK) {
robert_jw 0:b2805b6888dc 942 tcp_output(prev);
robert_jw 0:b2805b6888dc 943 }
robert_jw 0:b2805b6888dc 944 }
robert_jw 0:b2805b6888dc 945 }
robert_jw 0:b2805b6888dc 946 }
robert_jw 0:b2805b6888dc 947
robert_jw 0:b2805b6888dc 948
robert_jw 0:b2805b6888dc 949 /* Steps through all of the TIME-WAIT PCBs. */
robert_jw 0:b2805b6888dc 950 prev = NULL;
robert_jw 0:b2805b6888dc 951 pcb = tcp_tw_pcbs;
robert_jw 0:b2805b6888dc 952 while (pcb != NULL) {
robert_jw 0:b2805b6888dc 953 LWIP_ASSERT("tcp_slowtmr: TIME-WAIT pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
robert_jw 0:b2805b6888dc 954 pcb_remove = 0;
robert_jw 0:b2805b6888dc 955
robert_jw 0:b2805b6888dc 956 /* Check if this PCB has stayed long enough in TIME-WAIT */
robert_jw 0:b2805b6888dc 957 if ((u32_t)(tcp_ticks - pcb->tmr) > 2 * TCP_MSL / TCP_SLOW_INTERVAL) {
robert_jw 0:b2805b6888dc 958 ++pcb_remove;
robert_jw 0:b2805b6888dc 959 }
robert_jw 0:b2805b6888dc 960
robert_jw 0:b2805b6888dc 961
robert_jw 0:b2805b6888dc 962
robert_jw 0:b2805b6888dc 963 /* If the PCB should be removed, do it. */
robert_jw 0:b2805b6888dc 964 if (pcb_remove) {
robert_jw 0:b2805b6888dc 965 struct tcp_pcb *pcb2;
robert_jw 0:b2805b6888dc 966 tcp_pcb_purge(pcb);
robert_jw 0:b2805b6888dc 967 /* Remove PCB from tcp_tw_pcbs list. */
robert_jw 0:b2805b6888dc 968 if (prev != NULL) {
robert_jw 0:b2805b6888dc 969 LWIP_ASSERT("tcp_slowtmr: middle tcp != tcp_tw_pcbs", pcb != tcp_tw_pcbs);
robert_jw 0:b2805b6888dc 970 prev->next = pcb->next;
robert_jw 0:b2805b6888dc 971 } else {
robert_jw 0:b2805b6888dc 972 /* This PCB was the first. */
robert_jw 0:b2805b6888dc 973 LWIP_ASSERT("tcp_slowtmr: first pcb == tcp_tw_pcbs", tcp_tw_pcbs == pcb);
robert_jw 0:b2805b6888dc 974 tcp_tw_pcbs = pcb->next;
robert_jw 0:b2805b6888dc 975 }
robert_jw 0:b2805b6888dc 976 pcb2 = pcb;
robert_jw 0:b2805b6888dc 977 pcb = pcb->next;
robert_jw 0:b2805b6888dc 978 memp_free(MEMP_TCP_PCB, pcb2);
robert_jw 0:b2805b6888dc 979 } else {
robert_jw 0:b2805b6888dc 980 prev = pcb;
robert_jw 0:b2805b6888dc 981 pcb = pcb->next;
robert_jw 0:b2805b6888dc 982 }
robert_jw 0:b2805b6888dc 983 }
robert_jw 0:b2805b6888dc 984 }
robert_jw 0:b2805b6888dc 985
robert_jw 0:b2805b6888dc 986 /**
robert_jw 0:b2805b6888dc 987 * Is called every TCP_FAST_INTERVAL (250 ms) and process data previously
robert_jw 0:b2805b6888dc 988 * "refused" by upper layer (application) and sends delayed ACKs.
robert_jw 0:b2805b6888dc 989 *
robert_jw 0:b2805b6888dc 990 * Automatically called from tcp_tmr().
robert_jw 0:b2805b6888dc 991 */
robert_jw 0:b2805b6888dc 992 void
robert_jw 0:b2805b6888dc 993 tcp_fasttmr(void)
robert_jw 0:b2805b6888dc 994 {
robert_jw 0:b2805b6888dc 995 struct tcp_pcb *pcb = tcp_active_pcbs;
robert_jw 0:b2805b6888dc 996
robert_jw 0:b2805b6888dc 997 while(pcb != NULL) {
robert_jw 0:b2805b6888dc 998 struct tcp_pcb *next = pcb->next;
robert_jw 0:b2805b6888dc 999 /* If there is data which was previously "refused" by upper layer */
robert_jw 0:b2805b6888dc 1000 if (pcb->refused_data != NULL) {
robert_jw 0:b2805b6888dc 1001 /* Notify again application with data previously received. */
robert_jw 0:b2805b6888dc 1002 err_t err;
robert_jw 0:b2805b6888dc 1003 LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_fasttmr: notify kept packet\n"));
robert_jw 0:b2805b6888dc 1004 TCP_EVENT_RECV(pcb, pcb->refused_data, ERR_OK, err);
robert_jw 0:b2805b6888dc 1005 if (err == ERR_OK) {
robert_jw 0:b2805b6888dc 1006 pcb->refused_data = NULL;
robert_jw 0:b2805b6888dc 1007 } else if (err == ERR_ABRT) {
robert_jw 0:b2805b6888dc 1008 /* if err == ERR_ABRT, 'pcb' is already deallocated */
robert_jw 0:b2805b6888dc 1009 pcb = NULL;
robert_jw 0:b2805b6888dc 1010 }
robert_jw 0:b2805b6888dc 1011 }
robert_jw 0:b2805b6888dc 1012
robert_jw 0:b2805b6888dc 1013 /* send delayed ACKs */
robert_jw 0:b2805b6888dc 1014 if (pcb && (pcb->flags & TF_ACK_DELAY)) {
robert_jw 0:b2805b6888dc 1015 LWIP_DEBUGF(TCP_DEBUG, ("tcp_fasttmr: delayed ACK\n"));
robert_jw 0:b2805b6888dc 1016 tcp_ack_now(pcb);
robert_jw 0:b2805b6888dc 1017 tcp_output(pcb);
robert_jw 0:b2805b6888dc 1018 pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW);
robert_jw 0:b2805b6888dc 1019 }
robert_jw 0:b2805b6888dc 1020
robert_jw 0:b2805b6888dc 1021 pcb = next;
robert_jw 0:b2805b6888dc 1022 }
robert_jw 0:b2805b6888dc 1023 }
robert_jw 0:b2805b6888dc 1024
robert_jw 0:b2805b6888dc 1025 /**
robert_jw 0:b2805b6888dc 1026 * Deallocates a list of TCP segments (tcp_seg structures).
robert_jw 0:b2805b6888dc 1027 *
robert_jw 0:b2805b6888dc 1028 * @param seg tcp_seg list of TCP segments to free
robert_jw 0:b2805b6888dc 1029 */
robert_jw 0:b2805b6888dc 1030 void
robert_jw 0:b2805b6888dc 1031 tcp_segs_free(struct tcp_seg *seg)
robert_jw 0:b2805b6888dc 1032 {
robert_jw 0:b2805b6888dc 1033 while (seg != NULL) {
robert_jw 0:b2805b6888dc 1034 struct tcp_seg *next = seg->next;
robert_jw 0:b2805b6888dc 1035 tcp_seg_free(seg);
robert_jw 0:b2805b6888dc 1036 seg = next;
robert_jw 0:b2805b6888dc 1037 }
robert_jw 0:b2805b6888dc 1038 }
robert_jw 0:b2805b6888dc 1039
robert_jw 0:b2805b6888dc 1040 /**
robert_jw 0:b2805b6888dc 1041 * Frees a TCP segment (tcp_seg structure).
robert_jw 0:b2805b6888dc 1042 *
robert_jw 0:b2805b6888dc 1043 * @param seg single tcp_seg to free
robert_jw 0:b2805b6888dc 1044 */
robert_jw 0:b2805b6888dc 1045 void
robert_jw 0:b2805b6888dc 1046 tcp_seg_free(struct tcp_seg *seg)
robert_jw 0:b2805b6888dc 1047 {
robert_jw 0:b2805b6888dc 1048 if (seg != NULL) {
robert_jw 0:b2805b6888dc 1049 if (seg->p != NULL) {
robert_jw 0:b2805b6888dc 1050 pbuf_free(seg->p);
robert_jw 0:b2805b6888dc 1051 #if TCP_DEBUG
robert_jw 0:b2805b6888dc 1052 seg->p = NULL;
robert_jw 0:b2805b6888dc 1053 #endif /* TCP_DEBUG */
robert_jw 0:b2805b6888dc 1054 }
robert_jw 0:b2805b6888dc 1055 memp_free(MEMP_TCP_SEG, seg);
robert_jw 0:b2805b6888dc 1056 }
robert_jw 0:b2805b6888dc 1057 }
robert_jw 0:b2805b6888dc 1058
robert_jw 0:b2805b6888dc 1059 /**
robert_jw 0:b2805b6888dc 1060 * Sets the priority of a connection.
robert_jw 0:b2805b6888dc 1061 *
robert_jw 0:b2805b6888dc 1062 * @param pcb the tcp_pcb to manipulate
robert_jw 0:b2805b6888dc 1063 * @param prio new priority
robert_jw 0:b2805b6888dc 1064 */
robert_jw 0:b2805b6888dc 1065 void
robert_jw 0:b2805b6888dc 1066 tcp_setprio(struct tcp_pcb *pcb, u8_t prio)
robert_jw 0:b2805b6888dc 1067 {
robert_jw 0:b2805b6888dc 1068 pcb->prio = prio;
robert_jw 0:b2805b6888dc 1069 }
robert_jw 0:b2805b6888dc 1070
robert_jw 0:b2805b6888dc 1071 #if TCP_QUEUE_OOSEQ
robert_jw 0:b2805b6888dc 1072 /**
robert_jw 0:b2805b6888dc 1073 * Returns a copy of the given TCP segment.
robert_jw 0:b2805b6888dc 1074 * The pbuf and data are not copied, only the pointers
robert_jw 0:b2805b6888dc 1075 *
robert_jw 0:b2805b6888dc 1076 * @param seg the old tcp_seg
robert_jw 0:b2805b6888dc 1077 * @return a copy of seg
robert_jw 0:b2805b6888dc 1078 */
robert_jw 0:b2805b6888dc 1079 struct tcp_seg *
robert_jw 0:b2805b6888dc 1080 tcp_seg_copy(struct tcp_seg *seg)
robert_jw 0:b2805b6888dc 1081 {
robert_jw 0:b2805b6888dc 1082 struct tcp_seg *cseg;
robert_jw 0:b2805b6888dc 1083
robert_jw 0:b2805b6888dc 1084 cseg = (struct tcp_seg *)memp_malloc(MEMP_TCP_SEG);
robert_jw 0:b2805b6888dc 1085 if (cseg == NULL) {
robert_jw 0:b2805b6888dc 1086 return NULL;
robert_jw 0:b2805b6888dc 1087 }
robert_jw 0:b2805b6888dc 1088 SMEMCPY((u8_t *)cseg, (const u8_t *)seg, sizeof(struct tcp_seg));
robert_jw 0:b2805b6888dc 1089 pbuf_ref(cseg->p);
robert_jw 0:b2805b6888dc 1090 return cseg;
robert_jw 0:b2805b6888dc 1091 }
robert_jw 0:b2805b6888dc 1092 #endif /* TCP_QUEUE_OOSEQ */
robert_jw 0:b2805b6888dc 1093
robert_jw 0:b2805b6888dc 1094 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 1095 /**
robert_jw 0:b2805b6888dc 1096 * Default receive callback that is called if the user didn't register
robert_jw 0:b2805b6888dc 1097 * a recv callback for the pcb.
robert_jw 0:b2805b6888dc 1098 */
robert_jw 0:b2805b6888dc 1099 err_t
robert_jw 0:b2805b6888dc 1100 tcp_recv_null(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
robert_jw 0:b2805b6888dc 1101 {
robert_jw 0:b2805b6888dc 1102 LWIP_UNUSED_ARG(arg);
robert_jw 0:b2805b6888dc 1103 if (p != NULL) {
robert_jw 0:b2805b6888dc 1104 tcp_recved(pcb, p->tot_len);
robert_jw 0:b2805b6888dc 1105 pbuf_free(p);
robert_jw 0:b2805b6888dc 1106 } else if (err == ERR_OK) {
robert_jw 0:b2805b6888dc 1107 return tcp_close(pcb);
robert_jw 0:b2805b6888dc 1108 }
robert_jw 0:b2805b6888dc 1109 return ERR_OK;
robert_jw 0:b2805b6888dc 1110 }
robert_jw 0:b2805b6888dc 1111 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 1112
robert_jw 0:b2805b6888dc 1113 /**
robert_jw 0:b2805b6888dc 1114 * Kills the oldest active connection that has lower priority than prio.
robert_jw 0:b2805b6888dc 1115 *
robert_jw 0:b2805b6888dc 1116 * @param prio minimum priority
robert_jw 0:b2805b6888dc 1117 */
robert_jw 0:b2805b6888dc 1118 static void
robert_jw 0:b2805b6888dc 1119 tcp_kill_prio(u8_t prio)
robert_jw 0:b2805b6888dc 1120 {
robert_jw 0:b2805b6888dc 1121 struct tcp_pcb *pcb, *inactive;
robert_jw 0:b2805b6888dc 1122 u32_t inactivity;
robert_jw 0:b2805b6888dc 1123 u8_t mprio;
robert_jw 0:b2805b6888dc 1124
robert_jw 0:b2805b6888dc 1125
robert_jw 0:b2805b6888dc 1126 mprio = TCP_PRIO_MAX;
robert_jw 0:b2805b6888dc 1127
robert_jw 0:b2805b6888dc 1128 /* We kill the oldest active connection that has lower priority than prio. */
robert_jw 0:b2805b6888dc 1129 inactivity = 0;
robert_jw 0:b2805b6888dc 1130 inactive = NULL;
robert_jw 0:b2805b6888dc 1131 for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1132 if (pcb->prio <= prio &&
robert_jw 0:b2805b6888dc 1133 pcb->prio <= mprio &&
robert_jw 0:b2805b6888dc 1134 (u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
robert_jw 0:b2805b6888dc 1135 inactivity = tcp_ticks - pcb->tmr;
robert_jw 0:b2805b6888dc 1136 inactive = pcb;
robert_jw 0:b2805b6888dc 1137 mprio = pcb->prio;
robert_jw 0:b2805b6888dc 1138 }
robert_jw 0:b2805b6888dc 1139 }
robert_jw 0:b2805b6888dc 1140 if (inactive != NULL) {
robert_jw 0:b2805b6888dc 1141 LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_prio: killing oldest PCB %p (%"S32_F")\n",
robert_jw 0:b2805b6888dc 1142 (void *)inactive, inactivity));
robert_jw 0:b2805b6888dc 1143 tcp_abort(inactive);
robert_jw 0:b2805b6888dc 1144 }
robert_jw 0:b2805b6888dc 1145 }
robert_jw 0:b2805b6888dc 1146
robert_jw 0:b2805b6888dc 1147 /**
robert_jw 0:b2805b6888dc 1148 * Kills the oldest connection that is in TIME_WAIT state.
robert_jw 0:b2805b6888dc 1149 * Called from tcp_alloc() if no more connections are available.
robert_jw 0:b2805b6888dc 1150 */
robert_jw 0:b2805b6888dc 1151 static void
robert_jw 0:b2805b6888dc 1152 tcp_kill_timewait(void)
robert_jw 0:b2805b6888dc 1153 {
robert_jw 0:b2805b6888dc 1154 struct tcp_pcb *pcb, *inactive;
robert_jw 0:b2805b6888dc 1155 u32_t inactivity;
robert_jw 0:b2805b6888dc 1156
robert_jw 0:b2805b6888dc 1157 inactivity = 0;
robert_jw 0:b2805b6888dc 1158 inactive = NULL;
robert_jw 0:b2805b6888dc 1159 /* Go through the list of TIME_WAIT pcbs and get the oldest pcb. */
robert_jw 0:b2805b6888dc 1160 for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1161 if ((u32_t)(tcp_ticks - pcb->tmr) >= inactivity) {
robert_jw 0:b2805b6888dc 1162 inactivity = tcp_ticks - pcb->tmr;
robert_jw 0:b2805b6888dc 1163 inactive = pcb;
robert_jw 0:b2805b6888dc 1164 }
robert_jw 0:b2805b6888dc 1165 }
robert_jw 0:b2805b6888dc 1166 if (inactive != NULL) {
robert_jw 0:b2805b6888dc 1167 LWIP_DEBUGF(TCP_DEBUG, ("tcp_kill_timewait: killing oldest TIME-WAIT PCB %p (%"S32_F")\n",
robert_jw 0:b2805b6888dc 1168 (void *)inactive, inactivity));
robert_jw 0:b2805b6888dc 1169 tcp_abort(inactive);
robert_jw 0:b2805b6888dc 1170 }
robert_jw 0:b2805b6888dc 1171 }
robert_jw 0:b2805b6888dc 1172
robert_jw 0:b2805b6888dc 1173 /**
robert_jw 0:b2805b6888dc 1174 * Allocate a new tcp_pcb structure.
robert_jw 0:b2805b6888dc 1175 *
robert_jw 0:b2805b6888dc 1176 * @param prio priority for the new pcb
robert_jw 0:b2805b6888dc 1177 * @return a new tcp_pcb that initially is in state CLOSED
robert_jw 0:b2805b6888dc 1178 */
robert_jw 0:b2805b6888dc 1179 struct tcp_pcb *
robert_jw 0:b2805b6888dc 1180 tcp_alloc(u8_t prio)
robert_jw 0:b2805b6888dc 1181 {
robert_jw 0:b2805b6888dc 1182 struct tcp_pcb *pcb;
robert_jw 0:b2805b6888dc 1183 u32_t iss;
robert_jw 0:b2805b6888dc 1184
robert_jw 0:b2805b6888dc 1185 pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
robert_jw 0:b2805b6888dc 1186 if (pcb == NULL) {
robert_jw 0:b2805b6888dc 1187 /* Try killing oldest connection in TIME-WAIT. */
robert_jw 0:b2805b6888dc 1188 LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing off oldest TIME-WAIT connection\n"));
robert_jw 0:b2805b6888dc 1189 tcp_kill_timewait();
robert_jw 0:b2805b6888dc 1190 /* Try to allocate a tcp_pcb again. */
robert_jw 0:b2805b6888dc 1191 pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
robert_jw 0:b2805b6888dc 1192 if (pcb == NULL) {
robert_jw 0:b2805b6888dc 1193 /* Try killing active connections with lower priority than the new one. */
robert_jw 0:b2805b6888dc 1194 LWIP_DEBUGF(TCP_DEBUG, ("tcp_alloc: killing connection with prio lower than %d\n", prio));
robert_jw 0:b2805b6888dc 1195 tcp_kill_prio(prio);
robert_jw 0:b2805b6888dc 1196 /* Try to allocate a tcp_pcb again. */
robert_jw 0:b2805b6888dc 1197 pcb = (struct tcp_pcb *)memp_malloc(MEMP_TCP_PCB);
robert_jw 0:b2805b6888dc 1198 if (pcb != NULL) {
robert_jw 0:b2805b6888dc 1199 /* adjust err stats: memp_malloc failed twice before */
robert_jw 0:b2805b6888dc 1200 MEMP_STATS_DEC(err, MEMP_TCP_PCB);
robert_jw 0:b2805b6888dc 1201 }
robert_jw 0:b2805b6888dc 1202 }
robert_jw 0:b2805b6888dc 1203 if (pcb != NULL) {
robert_jw 0:b2805b6888dc 1204 /* adjust err stats: timewait PCB was freed above */
robert_jw 0:b2805b6888dc 1205 MEMP_STATS_DEC(err, MEMP_TCP_PCB);
robert_jw 0:b2805b6888dc 1206 }
robert_jw 0:b2805b6888dc 1207 }
robert_jw 0:b2805b6888dc 1208 if (pcb != NULL) {
robert_jw 0:b2805b6888dc 1209 memset(pcb, 0, sizeof(struct tcp_pcb));
robert_jw 0:b2805b6888dc 1210 pcb->prio = prio;
robert_jw 0:b2805b6888dc 1211 pcb->snd_buf = TCP_SND_BUF;
robert_jw 0:b2805b6888dc 1212 pcb->snd_queuelen = 0;
robert_jw 0:b2805b6888dc 1213 pcb->rcv_wnd = TCP_WND;
robert_jw 0:b2805b6888dc 1214 pcb->rcv_ann_wnd = TCP_WND;
robert_jw 0:b2805b6888dc 1215 pcb->tos = 0;
robert_jw 0:b2805b6888dc 1216 pcb->ttl = TCP_TTL;
robert_jw 0:b2805b6888dc 1217 /* As initial send MSS, we use TCP_MSS but limit it to 536.
robert_jw 0:b2805b6888dc 1218 The send MSS is updated when an MSS option is received. */
robert_jw 0:b2805b6888dc 1219 pcb->mss = (TCP_MSS > 536) ? 536 : TCP_MSS;
robert_jw 0:b2805b6888dc 1220 pcb->rto = 3000 / TCP_SLOW_INTERVAL;
robert_jw 0:b2805b6888dc 1221 pcb->sa = 0;
robert_jw 0:b2805b6888dc 1222 pcb->sv = 3000 / TCP_SLOW_INTERVAL;
robert_jw 0:b2805b6888dc 1223 pcb->rtime = -1;
robert_jw 0:b2805b6888dc 1224 pcb->cwnd = 1;
robert_jw 0:b2805b6888dc 1225 iss = tcp_next_iss();
robert_jw 0:b2805b6888dc 1226 pcb->snd_wl2 = iss;
robert_jw 0:b2805b6888dc 1227 pcb->snd_nxt = iss;
robert_jw 0:b2805b6888dc 1228 pcb->lastack = iss;
robert_jw 0:b2805b6888dc 1229 pcb->snd_lbb = iss;
robert_jw 0:b2805b6888dc 1230 pcb->tmr = tcp_ticks;
robert_jw 0:b2805b6888dc 1231
robert_jw 0:b2805b6888dc 1232 pcb->polltmr = 0;
robert_jw 0:b2805b6888dc 1233
robert_jw 0:b2805b6888dc 1234 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 1235 pcb->recv = tcp_recv_null;
robert_jw 0:b2805b6888dc 1236 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 1237
robert_jw 0:b2805b6888dc 1238 /* Init KEEPALIVE timer */
robert_jw 0:b2805b6888dc 1239 pcb->keep_idle = TCP_KEEPIDLE_DEFAULT;
robert_jw 0:b2805b6888dc 1240
robert_jw 0:b2805b6888dc 1241 #if LWIP_TCP_KEEPALIVE
robert_jw 0:b2805b6888dc 1242 pcb->keep_intvl = TCP_KEEPINTVL_DEFAULT;
robert_jw 0:b2805b6888dc 1243 pcb->keep_cnt = TCP_KEEPCNT_DEFAULT;
robert_jw 0:b2805b6888dc 1244 #endif /* LWIP_TCP_KEEPALIVE */
robert_jw 0:b2805b6888dc 1245
robert_jw 0:b2805b6888dc 1246 pcb->keep_cnt_sent = 0;
robert_jw 0:b2805b6888dc 1247 }
robert_jw 0:b2805b6888dc 1248 return pcb;
robert_jw 0:b2805b6888dc 1249 }
robert_jw 0:b2805b6888dc 1250
robert_jw 0:b2805b6888dc 1251 /**
robert_jw 0:b2805b6888dc 1252 * Creates a new TCP protocol control block but doesn't place it on
robert_jw 0:b2805b6888dc 1253 * any of the TCP PCB lists.
robert_jw 0:b2805b6888dc 1254 * The pcb is not put on any list until binding using tcp_bind().
robert_jw 0:b2805b6888dc 1255 *
robert_jw 0:b2805b6888dc 1256 * @internal: Maybe there should be a idle TCP PCB list where these
robert_jw 0:b2805b6888dc 1257 * PCBs are put on. Port reservation using tcp_bind() is implemented but
robert_jw 0:b2805b6888dc 1258 * allocated pcbs that are not bound can't be killed automatically if wanting
robert_jw 0:b2805b6888dc 1259 * to allocate a pcb with higher prio (@see tcp_kill_prio())
robert_jw 0:b2805b6888dc 1260 *
robert_jw 0:b2805b6888dc 1261 * @return a new tcp_pcb that initially is in state CLOSED
robert_jw 0:b2805b6888dc 1262 */
robert_jw 0:b2805b6888dc 1263 struct tcp_pcb *
robert_jw 0:b2805b6888dc 1264 tcp_new(void)
robert_jw 0:b2805b6888dc 1265 {
robert_jw 0:b2805b6888dc 1266 return tcp_alloc(TCP_PRIO_NORMAL);
robert_jw 0:b2805b6888dc 1267 }
robert_jw 0:b2805b6888dc 1268
robert_jw 0:b2805b6888dc 1269 /**
robert_jw 0:b2805b6888dc 1270 * Used to specify the argument that should be passed callback
robert_jw 0:b2805b6888dc 1271 * functions.
robert_jw 0:b2805b6888dc 1272 *
robert_jw 0:b2805b6888dc 1273 * @param pcb tcp_pcb to set the callback argument
robert_jw 0:b2805b6888dc 1274 * @param arg void pointer argument to pass to callback functions
robert_jw 0:b2805b6888dc 1275 */
robert_jw 0:b2805b6888dc 1276 void
robert_jw 0:b2805b6888dc 1277 tcp_arg(struct tcp_pcb *pcb, void *arg)
robert_jw 0:b2805b6888dc 1278 {
robert_jw 0:b2805b6888dc 1279 pcb->callback_arg = arg;
robert_jw 0:b2805b6888dc 1280 }
robert_jw 0:b2805b6888dc 1281 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 1282
robert_jw 0:b2805b6888dc 1283 /**
robert_jw 0:b2805b6888dc 1284 * Used to specify the function that should be called when a TCP
robert_jw 0:b2805b6888dc 1285 * connection receives data.
robert_jw 0:b2805b6888dc 1286 *
robert_jw 0:b2805b6888dc 1287 * @param pcb tcp_pcb to set the recv callback
robert_jw 0:b2805b6888dc 1288 * @param recv callback function to call for this pcb when data is received
robert_jw 0:b2805b6888dc 1289 */
robert_jw 0:b2805b6888dc 1290 void
robert_jw 0:b2805b6888dc 1291 tcp_recv(struct tcp_pcb *pcb, tcp_recv_fn recv)
robert_jw 0:b2805b6888dc 1292 {
robert_jw 0:b2805b6888dc 1293 pcb->recv = recv;
robert_jw 0:b2805b6888dc 1294 }
robert_jw 0:b2805b6888dc 1295
robert_jw 0:b2805b6888dc 1296 /**
robert_jw 0:b2805b6888dc 1297 * Used to specify the function that should be called when TCP data
robert_jw 0:b2805b6888dc 1298 * has been successfully delivered to the remote host.
robert_jw 0:b2805b6888dc 1299 *
robert_jw 0:b2805b6888dc 1300 * @param pcb tcp_pcb to set the sent callback
robert_jw 0:b2805b6888dc 1301 * @param sent callback function to call for this pcb when data is successfully sent
robert_jw 0:b2805b6888dc 1302 */
robert_jw 0:b2805b6888dc 1303 void
robert_jw 0:b2805b6888dc 1304 tcp_sent(struct tcp_pcb *pcb, tcp_sent_fn sent)
robert_jw 0:b2805b6888dc 1305 {
robert_jw 0:b2805b6888dc 1306 pcb->sent = sent;
robert_jw 0:b2805b6888dc 1307 }
robert_jw 0:b2805b6888dc 1308
robert_jw 0:b2805b6888dc 1309 /**
robert_jw 0:b2805b6888dc 1310 * Used to specify the function that should be called when a fatal error
robert_jw 0:b2805b6888dc 1311 * has occured on the connection.
robert_jw 0:b2805b6888dc 1312 *
robert_jw 0:b2805b6888dc 1313 * @param pcb tcp_pcb to set the err callback
robert_jw 0:b2805b6888dc 1314 * @param err callback function to call for this pcb when a fatal error
robert_jw 0:b2805b6888dc 1315 * has occured on the connection
robert_jw 0:b2805b6888dc 1316 */
robert_jw 0:b2805b6888dc 1317 void
robert_jw 0:b2805b6888dc 1318 tcp_err(struct tcp_pcb *pcb, tcp_err_fn err)
robert_jw 0:b2805b6888dc 1319 {
robert_jw 0:b2805b6888dc 1320 pcb->errf = err;
robert_jw 0:b2805b6888dc 1321 }
robert_jw 0:b2805b6888dc 1322
robert_jw 0:b2805b6888dc 1323 /**
robert_jw 0:b2805b6888dc 1324 * Used for specifying the function that should be called when a
robert_jw 0:b2805b6888dc 1325 * LISTENing connection has been connected to another host.
robert_jw 0:b2805b6888dc 1326 *
robert_jw 0:b2805b6888dc 1327 * @param pcb tcp_pcb to set the accept callback
robert_jw 0:b2805b6888dc 1328 * @param accept callback function to call for this pcb when LISTENing
robert_jw 0:b2805b6888dc 1329 * connection has been connected to another host
robert_jw 0:b2805b6888dc 1330 */
robert_jw 0:b2805b6888dc 1331 void
robert_jw 0:b2805b6888dc 1332 tcp_accept(struct tcp_pcb *pcb, tcp_accept_fn accept)
robert_jw 0:b2805b6888dc 1333 {
robert_jw 0:b2805b6888dc 1334 pcb->accept = accept;
robert_jw 0:b2805b6888dc 1335 }
robert_jw 0:b2805b6888dc 1336 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 1337
robert_jw 0:b2805b6888dc 1338
robert_jw 0:b2805b6888dc 1339 /**
robert_jw 0:b2805b6888dc 1340 * Used to specify the function that should be called periodically
robert_jw 0:b2805b6888dc 1341 * from TCP. The interval is specified in terms of the TCP coarse
robert_jw 0:b2805b6888dc 1342 * timer interval, which is called twice a second.
robert_jw 0:b2805b6888dc 1343 *
robert_jw 0:b2805b6888dc 1344 */
robert_jw 0:b2805b6888dc 1345 void
robert_jw 0:b2805b6888dc 1346 tcp_poll(struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval)
robert_jw 0:b2805b6888dc 1347 {
robert_jw 0:b2805b6888dc 1348 #if LWIP_CALLBACK_API
robert_jw 0:b2805b6888dc 1349 pcb->poll = poll;
robert_jw 0:b2805b6888dc 1350 #else /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 1351 LWIP_UNUSED_ARG(poll);
robert_jw 0:b2805b6888dc 1352 #endif /* LWIP_CALLBACK_API */
robert_jw 0:b2805b6888dc 1353 pcb->pollinterval = interval;
robert_jw 0:b2805b6888dc 1354 }
robert_jw 0:b2805b6888dc 1355
robert_jw 0:b2805b6888dc 1356 /**
robert_jw 0:b2805b6888dc 1357 * Purges a TCP PCB. Removes any buffered data and frees the buffer memory
robert_jw 0:b2805b6888dc 1358 * (pcb->ooseq, pcb->unsent and pcb->unacked are freed).
robert_jw 0:b2805b6888dc 1359 *
robert_jw 0:b2805b6888dc 1360 * @param pcb tcp_pcb to purge. The pcb itself is not deallocated!
robert_jw 0:b2805b6888dc 1361 */
robert_jw 0:b2805b6888dc 1362 void
robert_jw 0:b2805b6888dc 1363 tcp_pcb_purge(struct tcp_pcb *pcb)
robert_jw 0:b2805b6888dc 1364 {
robert_jw 0:b2805b6888dc 1365 if (pcb->state != CLOSED &&
robert_jw 0:b2805b6888dc 1366 pcb->state != TIME_WAIT &&
robert_jw 0:b2805b6888dc 1367 pcb->state != LISTEN) {
robert_jw 0:b2805b6888dc 1368
robert_jw 0:b2805b6888dc 1369 LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge\n"));
robert_jw 0:b2805b6888dc 1370
robert_jw 0:b2805b6888dc 1371 #if TCP_LISTEN_BACKLOG
robert_jw 0:b2805b6888dc 1372 if (pcb->state == SYN_RCVD) {
robert_jw 0:b2805b6888dc 1373 /* Need to find the corresponding listen_pcb and decrease its accepts_pending */
robert_jw 0:b2805b6888dc 1374 struct tcp_pcb_listen *lpcb;
robert_jw 0:b2805b6888dc 1375 LWIP_ASSERT("tcp_pcb_purge: pcb->state == SYN_RCVD but tcp_listen_pcbs is NULL",
robert_jw 0:b2805b6888dc 1376 tcp_listen_pcbs.listen_pcbs != NULL);
robert_jw 0:b2805b6888dc 1377 for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) {
robert_jw 0:b2805b6888dc 1378 if ((lpcb->local_port == pcb->local_port) &&
robert_jw 0:b2805b6888dc 1379 (ip_addr_isany(&lpcb->local_ip) ||
robert_jw 0:b2805b6888dc 1380 ip_addr_cmp(&pcb->local_ip, &lpcb->local_ip))) {
robert_jw 0:b2805b6888dc 1381 /* port and address of the listen pcb match the timed-out pcb */
robert_jw 0:b2805b6888dc 1382 LWIP_ASSERT("tcp_pcb_purge: listen pcb does not have accepts pending",
robert_jw 0:b2805b6888dc 1383 lpcb->accepts_pending > 0);
robert_jw 0:b2805b6888dc 1384 lpcb->accepts_pending--;
robert_jw 0:b2805b6888dc 1385 break;
robert_jw 0:b2805b6888dc 1386 }
robert_jw 0:b2805b6888dc 1387 }
robert_jw 0:b2805b6888dc 1388 }
robert_jw 0:b2805b6888dc 1389 #endif /* TCP_LISTEN_BACKLOG */
robert_jw 0:b2805b6888dc 1390
robert_jw 0:b2805b6888dc 1391
robert_jw 0:b2805b6888dc 1392 if (pcb->refused_data != NULL) {
robert_jw 0:b2805b6888dc 1393 LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->refused_data\n"));
robert_jw 0:b2805b6888dc 1394 pbuf_free(pcb->refused_data);
robert_jw 0:b2805b6888dc 1395 pcb->refused_data = NULL;
robert_jw 0:b2805b6888dc 1396 }
robert_jw 0:b2805b6888dc 1397 if (pcb->unsent != NULL) {
robert_jw 0:b2805b6888dc 1398 LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: not all data sent\n"));
robert_jw 0:b2805b6888dc 1399 }
robert_jw 0:b2805b6888dc 1400 if (pcb->unacked != NULL) {
robert_jw 0:b2805b6888dc 1401 LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->unacked\n"));
robert_jw 0:b2805b6888dc 1402 }
robert_jw 0:b2805b6888dc 1403 #if TCP_QUEUE_OOSEQ
robert_jw 0:b2805b6888dc 1404 if (pcb->ooseq != NULL) {
robert_jw 0:b2805b6888dc 1405 LWIP_DEBUGF(TCP_DEBUG, ("tcp_pcb_purge: data left on ->ooseq\n"));
robert_jw 0:b2805b6888dc 1406 }
robert_jw 0:b2805b6888dc 1407 tcp_segs_free(pcb->ooseq);
robert_jw 0:b2805b6888dc 1408 pcb->ooseq = NULL;
robert_jw 0:b2805b6888dc 1409 #endif /* TCP_QUEUE_OOSEQ */
robert_jw 0:b2805b6888dc 1410
robert_jw 0:b2805b6888dc 1411 /* Stop the retransmission timer as it will expect data on unacked
robert_jw 0:b2805b6888dc 1412 queue if it fires */
robert_jw 0:b2805b6888dc 1413 pcb->rtime = -1;
robert_jw 0:b2805b6888dc 1414
robert_jw 0:b2805b6888dc 1415 tcp_segs_free(pcb->unsent);
robert_jw 0:b2805b6888dc 1416 tcp_segs_free(pcb->unacked);
robert_jw 0:b2805b6888dc 1417 pcb->unacked = pcb->unsent = NULL;
robert_jw 0:b2805b6888dc 1418 #if TCP_OVERSIZE
robert_jw 0:b2805b6888dc 1419 pcb->unsent_oversize = 0;
robert_jw 0:b2805b6888dc 1420 #endif /* TCP_OVERSIZE */
robert_jw 0:b2805b6888dc 1421 }
robert_jw 0:b2805b6888dc 1422 }
robert_jw 0:b2805b6888dc 1423
robert_jw 0:b2805b6888dc 1424 /**
robert_jw 0:b2805b6888dc 1425 * Purges the PCB and removes it from a PCB list. Any delayed ACKs are sent first.
robert_jw 0:b2805b6888dc 1426 *
robert_jw 0:b2805b6888dc 1427 * @param pcblist PCB list to purge.
robert_jw 0:b2805b6888dc 1428 * @param pcb tcp_pcb to purge. The pcb itself is NOT deallocated!
robert_jw 0:b2805b6888dc 1429 */
robert_jw 0:b2805b6888dc 1430 void
robert_jw 0:b2805b6888dc 1431 tcp_pcb_remove(struct tcp_pcb **pcblist, struct tcp_pcb *pcb)
robert_jw 0:b2805b6888dc 1432 {
robert_jw 0:b2805b6888dc 1433 TCP_RMV(pcblist, pcb);
robert_jw 0:b2805b6888dc 1434
robert_jw 0:b2805b6888dc 1435 tcp_pcb_purge(pcb);
robert_jw 0:b2805b6888dc 1436
robert_jw 0:b2805b6888dc 1437 /* if there is an outstanding delayed ACKs, send it */
robert_jw 0:b2805b6888dc 1438 if (pcb->state != TIME_WAIT &&
robert_jw 0:b2805b6888dc 1439 pcb->state != LISTEN &&
robert_jw 0:b2805b6888dc 1440 pcb->flags & TF_ACK_DELAY) {
robert_jw 0:b2805b6888dc 1441 pcb->flags |= TF_ACK_NOW;
robert_jw 0:b2805b6888dc 1442 tcp_output(pcb);
robert_jw 0:b2805b6888dc 1443 }
robert_jw 0:b2805b6888dc 1444
robert_jw 0:b2805b6888dc 1445 if (pcb->state != LISTEN) {
robert_jw 0:b2805b6888dc 1446 LWIP_ASSERT("unsent segments leaking", pcb->unsent == NULL);
robert_jw 0:b2805b6888dc 1447 LWIP_ASSERT("unacked segments leaking", pcb->unacked == NULL);
robert_jw 0:b2805b6888dc 1448 #if TCP_QUEUE_OOSEQ
robert_jw 0:b2805b6888dc 1449 LWIP_ASSERT("ooseq segments leaking", pcb->ooseq == NULL);
robert_jw 0:b2805b6888dc 1450 #endif /* TCP_QUEUE_OOSEQ */
robert_jw 0:b2805b6888dc 1451 }
robert_jw 0:b2805b6888dc 1452
robert_jw 0:b2805b6888dc 1453 pcb->state = CLOSED;
robert_jw 0:b2805b6888dc 1454
robert_jw 0:b2805b6888dc 1455 LWIP_ASSERT("tcp_pcb_remove: tcp_pcbs_sane()", tcp_pcbs_sane());
robert_jw 0:b2805b6888dc 1456 }
robert_jw 0:b2805b6888dc 1457
robert_jw 0:b2805b6888dc 1458 /**
robert_jw 0:b2805b6888dc 1459 * Calculates a new initial sequence number for new connections.
robert_jw 0:b2805b6888dc 1460 *
robert_jw 0:b2805b6888dc 1461 * @return u32_t pseudo random sequence number
robert_jw 0:b2805b6888dc 1462 */
robert_jw 0:b2805b6888dc 1463 u32_t
robert_jw 0:b2805b6888dc 1464 tcp_next_iss(void)
robert_jw 0:b2805b6888dc 1465 {
robert_jw 0:b2805b6888dc 1466 static u32_t iss = 6510;
robert_jw 0:b2805b6888dc 1467
robert_jw 0:b2805b6888dc 1468 iss += tcp_ticks; /* XXX */
robert_jw 0:b2805b6888dc 1469 return iss;
robert_jw 0:b2805b6888dc 1470 }
robert_jw 0:b2805b6888dc 1471
robert_jw 0:b2805b6888dc 1472 #if TCP_CALCULATE_EFF_SEND_MSS
robert_jw 0:b2805b6888dc 1473 /**
robert_jw 0:b2805b6888dc 1474 * Calcluates the effective send mss that can be used for a specific IP address
robert_jw 0:b2805b6888dc 1475 * by using ip_route to determin the netif used to send to the address and
robert_jw 0:b2805b6888dc 1476 * calculating the minimum of TCP_MSS and that netif's mtu (if set).
robert_jw 0:b2805b6888dc 1477 */
robert_jw 0:b2805b6888dc 1478 u16_t
robert_jw 0:b2805b6888dc 1479 tcp_eff_send_mss(u16_t sendmss, ip_addr_t *addr)
robert_jw 0:b2805b6888dc 1480 {
robert_jw 0:b2805b6888dc 1481 u16_t mss_s;
robert_jw 0:b2805b6888dc 1482 struct netif *outif;
robert_jw 0:b2805b6888dc 1483
robert_jw 0:b2805b6888dc 1484 outif = ip_route(addr);
robert_jw 0:b2805b6888dc 1485 if ((outif != NULL) && (outif->mtu != 0)) {
robert_jw 0:b2805b6888dc 1486 mss_s = outif->mtu - IP_HLEN - TCP_HLEN;
robert_jw 0:b2805b6888dc 1487 /* RFC 1122, chap 4.2.2.6:
robert_jw 0:b2805b6888dc 1488 * Eff.snd.MSS = min(SendMSS+20, MMS_S) - TCPhdrsize - IPoptionsize
robert_jw 0:b2805b6888dc 1489 * We correct for TCP options in tcp_write(), and don't support IP options.
robert_jw 0:b2805b6888dc 1490 */
robert_jw 0:b2805b6888dc 1491 sendmss = LWIP_MIN(sendmss, mss_s);
robert_jw 0:b2805b6888dc 1492 }
robert_jw 0:b2805b6888dc 1493 return sendmss;
robert_jw 0:b2805b6888dc 1494 }
robert_jw 0:b2805b6888dc 1495 #endif /* TCP_CALCULATE_EFF_SEND_MSS */
robert_jw 0:b2805b6888dc 1496
robert_jw 0:b2805b6888dc 1497 const char*
robert_jw 0:b2805b6888dc 1498 tcp_debug_state_str(enum tcp_state s)
robert_jw 0:b2805b6888dc 1499 {
robert_jw 0:b2805b6888dc 1500 return tcp_state_str[s];
robert_jw 0:b2805b6888dc 1501 }
robert_jw 0:b2805b6888dc 1502
robert_jw 0:b2805b6888dc 1503 #if TCP_DEBUG || TCP_INPUT_DEBUG || TCP_OUTPUT_DEBUG
robert_jw 0:b2805b6888dc 1504 /**
robert_jw 0:b2805b6888dc 1505 * Print a tcp header for debugging purposes.
robert_jw 0:b2805b6888dc 1506 *
robert_jw 0:b2805b6888dc 1507 * @param tcphdr pointer to a struct tcp_hdr
robert_jw 0:b2805b6888dc 1508 */
robert_jw 0:b2805b6888dc 1509 void
robert_jw 0:b2805b6888dc 1510 tcp_debug_print(struct tcp_hdr *tcphdr)
robert_jw 0:b2805b6888dc 1511 {
robert_jw 0:b2805b6888dc 1512 LWIP_DEBUGF(TCP_DEBUG, ("TCP header:\n"));
robert_jw 0:b2805b6888dc 1513 LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
robert_jw 0:b2805b6888dc 1514 LWIP_DEBUGF(TCP_DEBUG, ("| %5"U16_F" | %5"U16_F" | (src port, dest port)\n",
robert_jw 0:b2805b6888dc 1515 ntohs(tcphdr->src), ntohs(tcphdr->dest)));
robert_jw 0:b2805b6888dc 1516 LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
robert_jw 0:b2805b6888dc 1517 LWIP_DEBUGF(TCP_DEBUG, ("| %010"U32_F" | (seq no)\n",
robert_jw 0:b2805b6888dc 1518 ntohl(tcphdr->seqno)));
robert_jw 0:b2805b6888dc 1519 LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
robert_jw 0:b2805b6888dc 1520 LWIP_DEBUGF(TCP_DEBUG, ("| %010"U32_F" | (ack no)\n",
robert_jw 0:b2805b6888dc 1521 ntohl(tcphdr->ackno)));
robert_jw 0:b2805b6888dc 1522 LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
robert_jw 0:b2805b6888dc 1523 LWIP_DEBUGF(TCP_DEBUG, ("| %2"U16_F" | |%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"%"U16_F"| %5"U16_F" | (hdrlen, flags (",
robert_jw 0:b2805b6888dc 1524 TCPH_HDRLEN(tcphdr),
robert_jw 0:b2805b6888dc 1525 TCPH_FLAGS(tcphdr) >> 5 & 1,
robert_jw 0:b2805b6888dc 1526 TCPH_FLAGS(tcphdr) >> 4 & 1,
robert_jw 0:b2805b6888dc 1527 TCPH_FLAGS(tcphdr) >> 3 & 1,
robert_jw 0:b2805b6888dc 1528 TCPH_FLAGS(tcphdr) >> 2 & 1,
robert_jw 0:b2805b6888dc 1529 TCPH_FLAGS(tcphdr) >> 1 & 1,
robert_jw 0:b2805b6888dc 1530 TCPH_FLAGS(tcphdr) & 1,
robert_jw 0:b2805b6888dc 1531 ntohs(tcphdr->wnd)));
robert_jw 0:b2805b6888dc 1532 tcp_debug_print_flags(TCPH_FLAGS(tcphdr));
robert_jw 0:b2805b6888dc 1533 LWIP_DEBUGF(TCP_DEBUG, ("), win)\n"));
robert_jw 0:b2805b6888dc 1534 LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
robert_jw 0:b2805b6888dc 1535 LWIP_DEBUGF(TCP_DEBUG, ("| 0x%04"X16_F" | %5"U16_F" | (chksum, urgp)\n",
robert_jw 0:b2805b6888dc 1536 ntohs(tcphdr->chksum), ntohs(tcphdr->urgp)));
robert_jw 0:b2805b6888dc 1537 LWIP_DEBUGF(TCP_DEBUG, ("+-------------------------------+\n"));
robert_jw 0:b2805b6888dc 1538 }
robert_jw 0:b2805b6888dc 1539
robert_jw 0:b2805b6888dc 1540 /**
robert_jw 0:b2805b6888dc 1541 * Print a tcp state for debugging purposes.
robert_jw 0:b2805b6888dc 1542 *
robert_jw 0:b2805b6888dc 1543 * @param s enum tcp_state to print
robert_jw 0:b2805b6888dc 1544 */
robert_jw 0:b2805b6888dc 1545 void
robert_jw 0:b2805b6888dc 1546 tcp_debug_print_state(enum tcp_state s)
robert_jw 0:b2805b6888dc 1547 {
robert_jw 0:b2805b6888dc 1548 LWIP_DEBUGF(TCP_DEBUG, ("State: %s\n", tcp_state_str[s]));
robert_jw 0:b2805b6888dc 1549 }
robert_jw 0:b2805b6888dc 1550
robert_jw 0:b2805b6888dc 1551 /**
robert_jw 0:b2805b6888dc 1552 * Print tcp flags for debugging purposes.
robert_jw 0:b2805b6888dc 1553 *
robert_jw 0:b2805b6888dc 1554 * @param flags tcp flags, all active flags are printed
robert_jw 0:b2805b6888dc 1555 */
robert_jw 0:b2805b6888dc 1556 void
robert_jw 0:b2805b6888dc 1557 tcp_debug_print_flags(u8_t flags)
robert_jw 0:b2805b6888dc 1558 {
robert_jw 0:b2805b6888dc 1559 if (flags & TCP_FIN) {
robert_jw 0:b2805b6888dc 1560 LWIP_DEBUGF(TCP_DEBUG, ("FIN "));
robert_jw 0:b2805b6888dc 1561 }
robert_jw 0:b2805b6888dc 1562 if (flags & TCP_SYN) {
robert_jw 0:b2805b6888dc 1563 LWIP_DEBUGF(TCP_DEBUG, ("SYN "));
robert_jw 0:b2805b6888dc 1564 }
robert_jw 0:b2805b6888dc 1565 if (flags & TCP_RST) {
robert_jw 0:b2805b6888dc 1566 LWIP_DEBUGF(TCP_DEBUG, ("RST "));
robert_jw 0:b2805b6888dc 1567 }
robert_jw 0:b2805b6888dc 1568 if (flags & TCP_PSH) {
robert_jw 0:b2805b6888dc 1569 LWIP_DEBUGF(TCP_DEBUG, ("PSH "));
robert_jw 0:b2805b6888dc 1570 }
robert_jw 0:b2805b6888dc 1571 if (flags & TCP_ACK) {
robert_jw 0:b2805b6888dc 1572 LWIP_DEBUGF(TCP_DEBUG, ("ACK "));
robert_jw 0:b2805b6888dc 1573 }
robert_jw 0:b2805b6888dc 1574 if (flags & TCP_URG) {
robert_jw 0:b2805b6888dc 1575 LWIP_DEBUGF(TCP_DEBUG, ("URG "));
robert_jw 0:b2805b6888dc 1576 }
robert_jw 0:b2805b6888dc 1577 if (flags & TCP_ECE) {
robert_jw 0:b2805b6888dc 1578 LWIP_DEBUGF(TCP_DEBUG, ("ECE "));
robert_jw 0:b2805b6888dc 1579 }
robert_jw 0:b2805b6888dc 1580 if (flags & TCP_CWR) {
robert_jw 0:b2805b6888dc 1581 LWIP_DEBUGF(TCP_DEBUG, ("CWR "));
robert_jw 0:b2805b6888dc 1582 }
robert_jw 0:b2805b6888dc 1583 LWIP_DEBUGF(TCP_DEBUG, ("\n"));
robert_jw 0:b2805b6888dc 1584 }
robert_jw 0:b2805b6888dc 1585
robert_jw 0:b2805b6888dc 1586 /**
robert_jw 0:b2805b6888dc 1587 * Print all tcp_pcbs in every list for debugging purposes.
robert_jw 0:b2805b6888dc 1588 */
robert_jw 0:b2805b6888dc 1589 void
robert_jw 0:b2805b6888dc 1590 tcp_debug_print_pcbs(void)
robert_jw 0:b2805b6888dc 1591 {
robert_jw 0:b2805b6888dc 1592 struct tcp_pcb *pcb;
robert_jw 0:b2805b6888dc 1593 LWIP_DEBUGF(TCP_DEBUG, ("Active PCB states:\n"));
robert_jw 0:b2805b6888dc 1594 for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1595 LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
robert_jw 0:b2805b6888dc 1596 pcb->local_port, pcb->remote_port,
robert_jw 0:b2805b6888dc 1597 pcb->snd_nxt, pcb->rcv_nxt));
robert_jw 0:b2805b6888dc 1598 tcp_debug_print_state(pcb->state);
robert_jw 0:b2805b6888dc 1599 }
robert_jw 0:b2805b6888dc 1600 LWIP_DEBUGF(TCP_DEBUG, ("Listen PCB states:\n"));
robert_jw 0:b2805b6888dc 1601 for(pcb = (struct tcp_pcb *)tcp_listen_pcbs.pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1602 LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
robert_jw 0:b2805b6888dc 1603 pcb->local_port, pcb->remote_port,
robert_jw 0:b2805b6888dc 1604 pcb->snd_nxt, pcb->rcv_nxt));
robert_jw 0:b2805b6888dc 1605 tcp_debug_print_state(pcb->state);
robert_jw 0:b2805b6888dc 1606 }
robert_jw 0:b2805b6888dc 1607 LWIP_DEBUGF(TCP_DEBUG, ("TIME-WAIT PCB states:\n"));
robert_jw 0:b2805b6888dc 1608 for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1609 LWIP_DEBUGF(TCP_DEBUG, ("Local port %"U16_F", foreign port %"U16_F" snd_nxt %"U32_F" rcv_nxt %"U32_F" ",
robert_jw 0:b2805b6888dc 1610 pcb->local_port, pcb->remote_port,
robert_jw 0:b2805b6888dc 1611 pcb->snd_nxt, pcb->rcv_nxt));
robert_jw 0:b2805b6888dc 1612 tcp_debug_print_state(pcb->state);
robert_jw 0:b2805b6888dc 1613 }
robert_jw 0:b2805b6888dc 1614 }
robert_jw 0:b2805b6888dc 1615
robert_jw 0:b2805b6888dc 1616 /**
robert_jw 0:b2805b6888dc 1617 * Check state consistency of the tcp_pcb lists.
robert_jw 0:b2805b6888dc 1618 */
robert_jw 0:b2805b6888dc 1619 s16_t
robert_jw 0:b2805b6888dc 1620 tcp_pcbs_sane(void)
robert_jw 0:b2805b6888dc 1621 {
robert_jw 0:b2805b6888dc 1622 struct tcp_pcb *pcb;
robert_jw 0:b2805b6888dc 1623 for(pcb = tcp_active_pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1624 LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != CLOSED", pcb->state != CLOSED);
robert_jw 0:b2805b6888dc 1625 LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != LISTEN", pcb->state != LISTEN);
robert_jw 0:b2805b6888dc 1626 LWIP_ASSERT("tcp_pcbs_sane: active pcb->state != TIME-WAIT", pcb->state != TIME_WAIT);
robert_jw 0:b2805b6888dc 1627 }
robert_jw 0:b2805b6888dc 1628 for(pcb = tcp_tw_pcbs; pcb != NULL; pcb = pcb->next) {
robert_jw 0:b2805b6888dc 1629 LWIP_ASSERT("tcp_pcbs_sane: tw pcb->state == TIME-WAIT", pcb->state == TIME_WAIT);
robert_jw 0:b2805b6888dc 1630 }
robert_jw 0:b2805b6888dc 1631 return 1;
robert_jw 0:b2805b6888dc 1632 }
robert_jw 0:b2805b6888dc 1633 #endif /* TCP_DEBUG */
robert_jw 0:b2805b6888dc 1634
robert_jw 0:b2805b6888dc 1635 #endif /* LWIP_TCP */