1/** 2 * @file 3 * TCP internal implementations (do not use in application code) 4 */ 5 6/* 7 * Copyright (c) 2001-2004 Swedish Institute of Computer Science. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without modification, 11 * are permitted provided that the following conditions are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 3. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 24 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 26 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 30 * OF SUCH DAMAGE. 31 * 32 * This file is part of the lwIP TCP/IP stack. 33 * 34 * Author: Adam Dunkels <adam@sics.se> 35 * 36 */ 37#ifndef LWIP_HDR_TCP_PRIV_H 38#define LWIP_HDR_TCP_PRIV_H 39 40#include "lwip/opt.h" 41 42#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */ 43 44#include "lwip/tcp.h" 45#include "lwip/mem.h" 46#include "lwip/pbuf.h" 47#include "lwip/ip.h" 48#include "lwip/icmp.h" 49#include "lwip/err.h" 50#include "lwip/ip6.h" 51#include "lwip/ip6_addr.h" 52#include "lwip/prot/tcp.h" 53 54#ifdef __cplusplus 55extern "C" { 56#endif 57 58/* Functions for interfacing with TCP: */ 59 60/* Lower layer interface to TCP: */ 61void tcp_init (void); /* Initialize this module. */ 62void tcp_tmr (void); /* Must be called every 63 TCP_TMR_INTERVAL 64 ms. (Typically 250 ms). */ 65/* It is also possible to call these two functions at the right 66 intervals (instead of calling tcp_tmr()). */ 67void tcp_slowtmr (void); 68void tcp_fasttmr (void); 69 70/* Call this from a netif driver (watch out for threading issues!) that has 71 returned a memory error on transmit and now has free buffers to send more. 72 This iterates all active pcbs that had an error and tries to call 73 tcp_output, so use this with care as it might slow down the system. */ 74void tcp_txnow (void); 75 76/* Only used by IP to pass a TCP segment to TCP: */ 77void tcp_input (struct pbuf *p, struct netif *inp); 78/* Used within the TCP code only: */ 79struct tcp_pcb * tcp_alloc (u8_t prio); 80void tcp_free (struct tcp_pcb *pcb); 81void tcp_abandon (struct tcp_pcb *pcb, int reset); 82err_t tcp_send_empty_ack(struct tcp_pcb *pcb); 83err_t tcp_rexmit (struct tcp_pcb *pcb); 84err_t tcp_rexmit_rto_prepare(struct tcp_pcb *pcb); 85void tcp_rexmit_rto_commit(struct tcp_pcb *pcb); 86void tcp_rexmit_rto (struct tcp_pcb *pcb); 87void tcp_rexmit_fast (struct tcp_pcb *pcb); 88u32_t tcp_update_rcv_ann_wnd(struct tcp_pcb *pcb); 89err_t tcp_process_refused_data(struct tcp_pcb *pcb); 90 91/** 92 * This is the Nagle algorithm: try to combine user data to send as few TCP 93 * segments as possible. Only send if 94 * - no previously transmitted data on the connection remains unacknowledged or 95 * - the TF_NODELAY flag is set (nagle algorithm turned off for this pcb) or 96 * - the only unsent segment is at least pcb->mss bytes long (or there is more 97 * than one unsent segment - with lwIP, this can happen although unsent->len < mss) 98 * - or if we are in fast-retransmit (TF_INFR) 99 */ 100#define tcp_do_output_nagle(tpcb) ((((tpcb)->unacked == NULL) || \ 101 ((tpcb)->flags & (TF_NODELAY | TF_INFR)) || \ 102 (((tpcb)->unsent != NULL) && (((tpcb)->unsent->next != NULL) || \ 103 ((tpcb)->unsent->len >= (tpcb)->mss))) || \ 104 ((tcp_sndbuf(tpcb) == 0) || (tcp_sndqueuelen(tpcb) >= TCP_SND_QUEUELEN)) \ 105 ) ? 1 : 0) 106#define tcp_output_nagle(tpcb) (tcp_do_output_nagle(tpcb) ? tcp_output(tpcb) : ERR_OK) 107 108 109#define TCP_SEQ_LT(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) < 0) 110#define TCP_SEQ_LEQ(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) <= 0) 111#define TCP_SEQ_GT(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) > 0) 112#define TCP_SEQ_GEQ(a,b) ((s32_t)((u32_t)(a) - (u32_t)(b)) >= 0) 113/* is b<=a<=c? */ 114#if 0 /* see bug #10548 */ 115#define TCP_SEQ_BETWEEN(a,b,c) ((c)-(b) >= (a)-(b)) 116#endif 117#define TCP_SEQ_BETWEEN(a,b,c) (TCP_SEQ_GEQ(a,b) && TCP_SEQ_LEQ(a,c)) 118 119#ifndef TCP_TMR_INTERVAL 120#define TCP_TMR_INTERVAL 250 /* The TCP timer interval in milliseconds. */ 121#endif /* TCP_TMR_INTERVAL */ 122 123#ifndef TCP_FAST_INTERVAL 124#define TCP_FAST_INTERVAL TCP_TMR_INTERVAL /* the fine grained timeout in milliseconds */ 125#endif /* TCP_FAST_INTERVAL */ 126 127#ifndef TCP_SLOW_INTERVAL 128#define TCP_SLOW_INTERVAL (2*TCP_TMR_INTERVAL) /* the coarse grained timeout in milliseconds */ 129#endif /* TCP_SLOW_INTERVAL */ 130 131#define TCP_FIN_WAIT_TIMEOUT 20000 /* milliseconds */ 132#define TCP_SYN_RCVD_TIMEOUT 20000 /* milliseconds */ 133 134#define TCP_OOSEQ_TIMEOUT 6U /* x RTO */ 135 136#ifndef TCP_MSL 137#define TCP_MSL 60000UL /* The maximum segment lifetime in milliseconds */ 138#endif 139 140/* Keepalive values, compliant with RFC 1122. Don't change this unless you know what you're doing */ 141#ifndef TCP_KEEPIDLE_DEFAULT 142#define TCP_KEEPIDLE_DEFAULT 7200000UL /* Default KEEPALIVE timer in milliseconds */ 143#endif 144 145#ifndef TCP_KEEPINTVL_DEFAULT 146#define TCP_KEEPINTVL_DEFAULT 75000UL /* Default Time between KEEPALIVE probes in milliseconds */ 147#endif 148 149#ifndef TCP_KEEPCNT_DEFAULT 150#define TCP_KEEPCNT_DEFAULT 9U /* Default Counter for KEEPALIVE probes */ 151#endif 152 153#define TCP_MAXIDLE TCP_KEEPCNT_DEFAULT * TCP_KEEPINTVL_DEFAULT /* Maximum KEEPALIVE probe time */ 154 155#define TCP_TCPLEN(seg) ((seg)->len + (((TCPH_FLAGS((seg)->tcphdr) & (TCP_FIN | TCP_SYN)) != 0) ? 1U : 0U)) 156 157/** Flags used on input processing, not on pcb->flags 158*/ 159#define TF_RESET (u8_t)0x08U /* Connection was reset. */ 160#define TF_CLOSED (u8_t)0x10U /* Connection was successfully closed. */ 161#define TF_GOT_FIN (u8_t)0x20U /* Connection was closed by the remote end. */ 162 163 164#if LWIP_EVENT_API 165 166#define TCP_EVENT_ACCEPT(lpcb,pcb,arg,err,ret) ret = lwip_tcp_event(arg, (pcb),\ 167 LWIP_EVENT_ACCEPT, NULL, 0, err) 168#define TCP_EVENT_SENT(pcb,space,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\ 169 LWIP_EVENT_SENT, NULL, space, ERR_OK) 170#define TCP_EVENT_RECV(pcb,p,err,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\ 171 LWIP_EVENT_RECV, (p), 0, (err)) 172#define TCP_EVENT_CLOSED(pcb,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\ 173 LWIP_EVENT_RECV, NULL, 0, ERR_OK) 174#define TCP_EVENT_CONNECTED(pcb,err,ret) ret = lwip_tcp_event((pcb)->callback_arg, (pcb),\ 175 LWIP_EVENT_CONNECTED, NULL, 0, (err)) 176#define TCP_EVENT_POLL(pcb,ret) do { if ((pcb)->state != SYN_RCVD) { \ 177 ret = lwip_tcp_event((pcb)->callback_arg, (pcb), LWIP_EVENT_POLL, NULL, 0, ERR_OK); \ 178 } else { \ 179 ret = ERR_ARG; } } while(0) 180/* For event API, last state SYN_RCVD must be excluded here: the application 181 has not seen this pcb, yet! */ 182#define TCP_EVENT_ERR(last_state,errf,arg,err) do { if (last_state != SYN_RCVD) { \ 183 lwip_tcp_event((arg), NULL, LWIP_EVENT_ERR, NULL, 0, (err)); } } while(0) 184 185#else /* LWIP_EVENT_API */ 186 187#define TCP_EVENT_ACCEPT(lpcb,pcb,arg,err,ret) \ 188 do { \ 189 if((lpcb)->accept != NULL) \ 190 (ret) = (lpcb)->accept((arg),(pcb),(err)); \ 191 else (ret) = ERR_ARG; \ 192 } while (0) 193 194#define TCP_EVENT_SENT(pcb,space,ret) \ 195 do { \ 196 if((pcb)->sent != NULL) \ 197 (ret) = (pcb)->sent((pcb)->callback_arg,(pcb),(space)); \ 198 else (ret) = ERR_OK; \ 199 } while (0) 200 201#define TCP_EVENT_RECV(pcb,p,err,ret) \ 202 do { \ 203 if((pcb)->recv != NULL) { \ 204 (ret) = (pcb)->recv((pcb)->callback_arg,(pcb),(p),(err));\ 205 } else { \ 206 (ret) = tcp_recv_null(NULL, (pcb), (p), (err)); \ 207 } \ 208 } while (0) 209 210#define TCP_EVENT_CLOSED(pcb,ret) \ 211 do { \ 212 if(((pcb)->recv != NULL)) { \ 213 (ret) = (pcb)->recv((pcb)->callback_arg,(pcb),NULL,ERR_OK);\ 214 } else { \ 215 (ret) = ERR_OK; \ 216 } \ 217 } while (0) 218 219#define TCP_EVENT_CONNECTED(pcb,err,ret) \ 220 do { \ 221 if((pcb)->connected != NULL) \ 222 (ret) = (pcb)->connected((pcb)->callback_arg,(pcb),(err)); \ 223 else (ret) = ERR_OK; \ 224 } while (0) 225 226#define TCP_EVENT_POLL(pcb,ret) \ 227 do { \ 228 if((pcb)->poll != NULL) \ 229 (ret) = (pcb)->poll((pcb)->callback_arg,(pcb)); \ 230 else (ret) = ERR_OK; \ 231 } while (0) 232 233#define TCP_EVENT_ERR(last_state,errf,arg,err) \ 234 do { \ 235 LWIP_UNUSED_ARG(last_state); \ 236 if((errf) != NULL) \ 237 (errf)((arg),(err)); \ 238 } while (0) 239 240#endif /* LWIP_EVENT_API */ 241 242/** Enabled extra-check for TCP_OVERSIZE if LWIP_DEBUG is enabled */ 243#if TCP_OVERSIZE && defined(LWIP_DEBUG) 244#define TCP_OVERSIZE_DBGCHECK 1 245#else 246#define TCP_OVERSIZE_DBGCHECK 0 247#endif 248 249/** Don't generate checksum on copy if CHECKSUM_GEN_TCP is disabled */ 250#define TCP_CHECKSUM_ON_COPY (LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_TCP) 251 252/* This structure represents a TCP segment on the unsent, unacked and ooseq queues */ 253struct tcp_seg { 254 struct tcp_seg *next; /* used when putting segments on a queue */ 255 struct pbuf *p; /* buffer containing data + TCP header */ 256 u16_t len; /* the TCP length of this segment */ 257#if TCP_OVERSIZE_DBGCHECK 258 u16_t oversize_left; /* Extra bytes available at the end of the last 259 pbuf in unsent (used for asserting vs. 260 tcp_pcb.unsent_oversize only) */ 261#endif /* TCP_OVERSIZE_DBGCHECK */ 262#if TCP_CHECKSUM_ON_COPY 263 u16_t chksum; 264 u8_t chksum_swapped; 265#endif /* TCP_CHECKSUM_ON_COPY */ 266 u8_t flags; 267#define TF_SEG_OPTS_MSS (u8_t)0x01U /* Include MSS option (only used in SYN segments) */ 268#define TF_SEG_OPTS_TS (u8_t)0x02U /* Include timestamp option. */ 269#define TF_SEG_DATA_CHECKSUMMED (u8_t)0x04U /* ALL data (not the header) is 270 checksummed into 'chksum' */ 271#define TF_SEG_OPTS_WND_SCALE (u8_t)0x08U /* Include WND SCALE option (only used in SYN segments) */ 272#define TF_SEG_OPTS_SACK_PERM (u8_t)0x10U /* Include SACK Permitted option (only used in SYN segments) */ 273 struct tcp_hdr *tcphdr; /* the TCP header */ 274}; 275 276#define LWIP_TCP_OPT_EOL 0 277#define LWIP_TCP_OPT_NOP 1 278#define LWIP_TCP_OPT_MSS 2 279#define LWIP_TCP_OPT_WS 3 280#define LWIP_TCP_OPT_SACK_PERM 4 281#define LWIP_TCP_OPT_TS 8 282 283#define LWIP_TCP_OPT_LEN_MSS 4 284#if LWIP_TCP_TIMESTAMPS 285#define LWIP_TCP_OPT_LEN_TS 10 286#define LWIP_TCP_OPT_LEN_TS_OUT 12 /* aligned for output (includes NOP padding) */ 287#else 288#define LWIP_TCP_OPT_LEN_TS_OUT 0 289#endif 290#if LWIP_WND_SCALE 291#define LWIP_TCP_OPT_LEN_WS 3 292#define LWIP_TCP_OPT_LEN_WS_OUT 4 /* aligned for output (includes NOP padding) */ 293#else 294#define LWIP_TCP_OPT_LEN_WS_OUT 0 295#endif 296 297#if LWIP_TCP_SACK_OUT 298#define LWIP_TCP_OPT_LEN_SACK_PERM 2 299#define LWIP_TCP_OPT_LEN_SACK_PERM_OUT 4 /* aligned for output (includes NOP padding) */ 300#else 301#define LWIP_TCP_OPT_LEN_SACK_PERM_OUT 0 302#endif 303 304#define LWIP_TCP_OPT_LENGTH(flags) \ 305 ((flags) & TF_SEG_OPTS_MSS ? LWIP_TCP_OPT_LEN_MSS : 0) + \ 306 ((flags) & TF_SEG_OPTS_TS ? LWIP_TCP_OPT_LEN_TS_OUT : 0) + \ 307 ((flags) & TF_SEG_OPTS_WND_SCALE ? LWIP_TCP_OPT_LEN_WS_OUT : 0) + \ 308 ((flags) & TF_SEG_OPTS_SACK_PERM ? LWIP_TCP_OPT_LEN_SACK_PERM_OUT : 0) 309 310/** This returns a TCP header option for MSS in an u32_t */ 311#define TCP_BUILD_MSS_OPTION(mss) lwip_htonl(0x02040000 | ((mss) & 0xFFFF)) 312 313#if LWIP_WND_SCALE 314#define TCPWNDSIZE_F U32_F 315#define TCPWND_MAX 0xFFFFFFFFU 316#define TCPWND_CHECK16(x) LWIP_ASSERT("window size > 0xFFFF", (x) <= 0xFFFF) 317#define TCPWND_MIN16(x) ((u16_t)LWIP_MIN((x), 0xFFFF)) 318#else /* LWIP_WND_SCALE */ 319#define TCPWNDSIZE_F U16_F 320#define TCPWND_MAX 0xFFFFU 321#define TCPWND_CHECK16(x) 322#define TCPWND_MIN16(x) x 323#endif /* LWIP_WND_SCALE */ 324 325/* Global variables: */ 326extern struct tcp_pcb *tcp_input_pcb; 327extern u32_t tcp_ticks; 328extern u8_t tcp_active_pcbs_changed; 329 330/* The TCP PCB lists. */ 331union tcp_listen_pcbs_t { /* List of all TCP PCBs in LISTEN state. */ 332 struct tcp_pcb_listen *listen_pcbs; 333 struct tcp_pcb *pcbs; 334}; 335extern struct tcp_pcb *tcp_bound_pcbs; 336extern union tcp_listen_pcbs_t tcp_listen_pcbs; 337extern struct tcp_pcb *tcp_active_pcbs; /* List of all TCP PCBs that are in a 338 state in which they accept or send 339 data. */ 340extern struct tcp_pcb *tcp_tw_pcbs; /* List of all TCP PCBs in TIME-WAIT. */ 341 342#define NUM_TCP_PCB_LISTS_NO_TIME_WAIT 3 343#define NUM_TCP_PCB_LISTS 4 344extern struct tcp_pcb ** const tcp_pcb_lists[NUM_TCP_PCB_LISTS]; 345 346/* Axioms about the above lists: 347 1) Every TCP PCB that is not CLOSED is in one of the lists. 348 2) A PCB is only in one of the lists. 349 3) All PCBs in the tcp_listen_pcbs list is in LISTEN state. 350 4) All PCBs in the tcp_tw_pcbs list is in TIME-WAIT state. 351*/ 352/* Define two macros, TCP_REG and TCP_RMV that registers a TCP PCB 353 with a PCB list or removes a PCB from a list, respectively. */ 354#ifndef TCP_DEBUG_PCB_LISTS 355#define TCP_DEBUG_PCB_LISTS 0 356#endif 357#if TCP_DEBUG_PCB_LISTS 358#define TCP_REG(pcbs, npcb) do {\ 359 struct tcp_pcb *tcp_tmp_pcb; \ 360 LWIP_DEBUGF(TCP_DEBUG, ("TCP_REG %p local port %"U16_F"\n", (void *)(npcb), (npcb)->local_port)); \ 361 for (tcp_tmp_pcb = *(pcbs); \ 362 tcp_tmp_pcb != NULL; \ 363 tcp_tmp_pcb = tcp_tmp_pcb->next) { \ 364 LWIP_ASSERT("TCP_REG: already registered\n", tcp_tmp_pcb != (npcb)); \ 365 } \ 366 LWIP_ASSERT("TCP_REG: pcb->state != CLOSED", ((pcbs) == &tcp_bound_pcbs) || ((npcb)->state != CLOSED)); \ 367 (npcb)->next = *(pcbs); \ 368 LWIP_ASSERT("TCP_REG: npcb->next != npcb", (npcb)->next != (npcb)); \ 369 *(pcbs) = (npcb); \ 370 LWIP_ASSERT("TCP_REG: tcp_pcbs sane", tcp_pcbs_sane()); \ 371 tcp_timer_needed(); \ 372 } while(0) 373#define TCP_RMV(pcbs, npcb) do { \ 374 struct tcp_pcb *tcp_tmp_pcb; \ 375 LWIP_ASSERT("TCP_RMV: pcbs != NULL", *(pcbs) != NULL); \ 376 LWIP_DEBUGF(TCP_DEBUG, ("TCP_RMV: removing %p from %p\n", (void *)(npcb), (void *)(*(pcbs)))); \ 377 if(*(pcbs) == (npcb)) { \ 378 *(pcbs) = (*pcbs)->next; \ 379 } else for (tcp_tmp_pcb = *(pcbs); tcp_tmp_pcb != NULL; tcp_tmp_pcb = tcp_tmp_pcb->next) { \ 380 if(tcp_tmp_pcb->next == (npcb)) { \ 381 tcp_tmp_pcb->next = (npcb)->next; \ 382 break; \ 383 } \ 384 } \ 385 (npcb)->next = NULL; \ 386 LWIP_ASSERT("TCP_RMV: tcp_pcbs sane", tcp_pcbs_sane()); \ 387 LWIP_DEBUGF(TCP_DEBUG, ("TCP_RMV: removed %p from %p\n", (void *)(npcb), (void *)(*(pcbs)))); \ 388 } while(0) 389 390#else /* LWIP_DEBUG */ 391 392#define TCP_REG(pcbs, npcb) \ 393 do { \ 394 (npcb)->next = *pcbs; \ 395 *(pcbs) = (npcb); \ 396 tcp_timer_needed(); \ 397 } while (0) 398 399#define TCP_RMV(pcbs, npcb) \ 400 do { \ 401 if(*(pcbs) == (npcb)) { \ 402 (*(pcbs)) = (*pcbs)->next; \ 403 } \ 404 else { \ 405 struct tcp_pcb *tcp_tmp_pcb; \ 406 for (tcp_tmp_pcb = *pcbs; \ 407 tcp_tmp_pcb != NULL; \ 408 tcp_tmp_pcb = tcp_tmp_pcb->next) { \ 409 if(tcp_tmp_pcb->next == (npcb)) { \ 410 tcp_tmp_pcb->next = (npcb)->next; \ 411 break; \ 412 } \ 413 } \ 414 } \ 415 (npcb)->next = NULL; \ 416 } while(0) 417 418#endif /* LWIP_DEBUG */ 419 420#define TCP_REG_ACTIVE(npcb) \ 421 do { \ 422 TCP_REG(&tcp_active_pcbs, npcb); \ 423 tcp_active_pcbs_changed = 1; \ 424 } while (0) 425 426#define TCP_RMV_ACTIVE(npcb) \ 427 do { \ 428 TCP_RMV(&tcp_active_pcbs, npcb); \ 429 tcp_active_pcbs_changed = 1; \ 430 } while (0) 431 432#define TCP_PCB_REMOVE_ACTIVE(pcb) \ 433 do { \ 434 tcp_pcb_remove(&tcp_active_pcbs, pcb); \ 435 tcp_active_pcbs_changed = 1; \ 436 } while (0) 437 438 439/* Internal functions: */ 440struct tcp_pcb *tcp_pcb_copy(struct tcp_pcb *pcb); 441void tcp_pcb_purge(struct tcp_pcb *pcb); 442void tcp_pcb_remove(struct tcp_pcb **pcblist, struct tcp_pcb *pcb); 443 444void tcp_segs_free(struct tcp_seg *seg); 445void tcp_seg_free(struct tcp_seg *seg); 446struct tcp_seg *tcp_seg_copy(struct tcp_seg *seg); 447 448#define tcp_ack(pcb) \ 449 do { \ 450 if((pcb)->flags & TF_ACK_DELAY) { \ 451 tcp_clear_flags(pcb, TF_ACK_DELAY); \ 452 tcp_ack_now(pcb); \ 453 } \ 454 else { \ 455 tcp_set_flags(pcb, TF_ACK_DELAY); \ 456 } \ 457 } while (0) 458 459#define tcp_ack_now(pcb) \ 460 tcp_set_flags(pcb, TF_ACK_NOW) 461 462err_t tcp_send_fin(struct tcp_pcb *pcb); 463err_t tcp_enqueue_flags(struct tcp_pcb *pcb, u8_t flags); 464 465void tcp_rexmit_seg(struct tcp_pcb *pcb, struct tcp_seg *seg); 466 467void tcp_rst(const struct tcp_pcb* pcb, u32_t seqno, u32_t ackno, 468 const ip_addr_t *local_ip, const ip_addr_t *remote_ip, 469 u16_t local_port, u16_t remote_port); 470 471u32_t tcp_next_iss(struct tcp_pcb *pcb); 472 473err_t tcp_keepalive(struct tcp_pcb *pcb); 474err_t tcp_split_unsent_seg(struct tcp_pcb *pcb, u16_t split); 475err_t tcp_zero_window_probe(struct tcp_pcb *pcb); 476void tcp_trigger_input_pcb_close(void); 477 478#if TCP_CALCULATE_EFF_SEND_MSS 479u16_t tcp_eff_send_mss_netif(u16_t sendmss, struct netif *outif, 480 const ip_addr_t *dest); 481#define tcp_eff_send_mss(sendmss, src, dest) \ 482 tcp_eff_send_mss_netif(sendmss, ip_route(src, dest), dest) 483#endif /* TCP_CALCULATE_EFF_SEND_MSS */ 484 485#if LWIP_CALLBACK_API 486err_t tcp_recv_null(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err); 487#endif /* LWIP_CALLBACK_API */ 488 489#if TCP_DEBUG || TCP_INPUT_DEBUG || TCP_OUTPUT_DEBUG 490void tcp_debug_print(struct tcp_hdr *tcphdr); 491void tcp_debug_print_flags(u8_t flags); 492void tcp_debug_print_state(enum tcp_state s); 493void tcp_debug_print_pcbs(void); 494s16_t tcp_pcbs_sane(void); 495#else 496# define tcp_debug_print(tcphdr) 497# define tcp_debug_print_flags(flags) 498# define tcp_debug_print_state(s) 499# define tcp_debug_print_pcbs() 500# define tcp_pcbs_sane() 1 501#endif /* TCP_DEBUG */ 502 503/** External function (implemented in timers.c), called when TCP detects 504 * that a timer is needed (i.e. active- or time-wait-pcb found). */ 505void tcp_timer_needed(void); 506 507void tcp_netif_ip_addr_changed(const ip_addr_t* old_addr, const ip_addr_t* new_addr); 508 509#if TCP_QUEUE_OOSEQ 510void tcp_free_ooseq(struct tcp_pcb *pcb); 511#endif 512 513#if LWIP_TCP_PCB_NUM_EXT_ARGS 514err_t tcp_ext_arg_invoke_callbacks_passive_open(struct tcp_pcb_listen *lpcb, struct tcp_pcb *cpcb); 515#endif 516 517#ifdef __cplusplus 518} 519#endif 520 521#endif /* LWIP_TCP */ 522 523#endif /* LWIP_HDR_TCP_PRIV_H */ 524