| /* |
| * Copyright (c) 2001-2004 Swedish Institute of Computer Science. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without modification, |
| * are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
| * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
| * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
| * OF SUCH DAMAGE. |
| * |
| * This file is part of the lwIP TCP/IP stack. |
| * |
| * Author: Adam Dunkels <adam@sics.se> |
| * |
| */ |
| #ifndef __LWIP_TCP_H__ |
| #define __LWIP_TCP_H__ |
| |
| #include "lwip/opt.h" |
| |
| #if LWIP_TCP /* don't build if not configured for use in lwipopts.h */ |
| |
| #include "lwip/sys.h" |
| #include "lwip/mem.h" |
| #include "lwip/pbuf.h" |
| #include "lwip/ip.h" |
| #include "lwip/icmp.h" |
| #include "lwip/err.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| struct tcp_pcb; |
| |
| /** Function prototype for tcp accept callback functions. Called when a new |
| * connection can be accepted on a listening pcb. |
| * |
| * @param arg Additional argument to pass to the callback function (@see tcp_arg()) |
| * @param newpcb The new connection pcb |
| * @param err An error code if there has been an error accepting. |
| * Only return ERR_ABRT if you have called tcp_abort from within the |
| * callback function! |
| */ |
| typedef err_t (*tcp_accept_fn)(void *arg, struct tcp_pcb *newpcb, err_t err); |
| |
| /** Function prototype for tcp receive callback functions. Called when data has |
| * been received. |
| * |
| * @param arg Additional argument to pass to the callback function (@see tcp_arg()) |
| * @param tpcb The connection pcb which received data |
| * @param p The received data (or NULL when the connection has been closed!) |
| * @param err An error code if there has been an error receiving |
| * Only return ERR_ABRT if you have called tcp_abort from within the |
| * callback function! |
| */ |
| typedef err_t (*tcp_recv_fn)(void *arg, struct tcp_pcb *tpcb, |
| struct pbuf *p, err_t err); |
| |
| /** Function prototype for tcp sent callback functions. Called when sent data has |
| * been acknowledged by the remote side. Use it to free corresponding resources. |
| * This also means that the pcb has now space available to send new data. |
| * |
| * @param arg Additional argument to pass to the callback function (@see tcp_arg()) |
| * @param tpcb The connection pcb for which data has been acknowledged |
| * @param len The amount of bytes acknowledged |
| * @return ERR_OK: try to send some data by calling tcp_output |
| * Only return ERR_ABRT if you have called tcp_abort from within the |
| * callback function! |
| */ |
| typedef err_t (*tcp_sent_fn)(void *arg, struct tcp_pcb *tpcb, |
| u16_t len); |
| |
| /** Function prototype for tcp poll callback functions. Called periodically as |
| * specified by @see tcp_poll. |
| * |
| * @param arg Additional argument to pass to the callback function (@see tcp_arg()) |
| * @param tpcb tcp pcb |
| * @return ERR_OK: try to send some data by calling tcp_output |
| * Only return ERR_ABRT if you have called tcp_abort from within the |
| * callback function! |
| */ |
| typedef err_t (*tcp_poll_fn)(void *arg, struct tcp_pcb *tpcb); |
| |
| /** Function prototype for tcp error callback functions. Called when the pcb |
| * receives a RST or is unexpectedly closed for any other reason. |
| * |
| * @note The corresponding pcb is already freed when this callback is called! |
| * |
| * @param arg Additional argument to pass to the callback function (@see tcp_arg()) |
| * @param err Error code to indicate why the pcb has been closed |
| * ERR_ABRT: aborted through tcp_abort or by a TCP timer |
| * ERR_RST: the connection was reset by the remote host |
| */ |
| typedef void (*tcp_err_fn)(void *arg, err_t err); |
| |
| /** Function prototype for tcp connected callback functions. Called when a pcb |
| * is connected to the remote side after initiating a connection attempt by |
| * calling tcp_connect(). |
| * |
| * @param arg Additional argument to pass to the callback function (@see tcp_arg()) |
| * @param tpcb The connection pcb which is connected |
| * @param err An unused error code, always ERR_OK currently ;-) TODO! |
| * Only return ERR_ABRT if you have called tcp_abort from within the |
| * callback function! |
| * |
| * @note When a connection attempt fails, the error callback is currently called! |
| */ |
| typedef err_t (*tcp_connected_fn)(void *arg, struct tcp_pcb *tpcb, err_t err); |
| |
| enum tcp_state { |
| CLOSED = 0, |
| LISTEN = 1, |
| SYN_SENT = 2, |
| SYN_RCVD = 3, |
| ESTABLISHED = 4, |
| FIN_WAIT_1 = 5, |
| FIN_WAIT_2 = 6, |
| CLOSE_WAIT = 7, |
| CLOSING = 8, |
| LAST_ACK = 9, |
| TIME_WAIT = 10 |
| }; |
| |
| #if LWIP_CALLBACK_API |
| /* Function to call when a listener has been connected. |
| * @param arg user-supplied argument (tcp_pcb.callback_arg) |
| * @param pcb a new tcp_pcb that now is connected |
| * @param err an error argument (TODO: that is current always ERR_OK?) |
| * @return ERR_OK: accept the new connection, |
| * any other err_t abortsthe new connection |
| */ |
| #define DEF_ACCEPT_CALLBACK tcp_accept_fn accept; |
| #else /* LWIP_CALLBACK_API */ |
| #define DEF_ACCEPT_CALLBACK |
| #endif /* LWIP_CALLBACK_API */ |
| |
| /** |
| * members common to struct tcp_pcb and struct tcp_listen_pcb |
| */ |
| #define TCP_PCB_COMMON(type) \ |
| type *next; /* for the linked list */ \ |
| enum tcp_state state; /* TCP state */ \ |
| u8_t prio; \ |
| void *callback_arg; \ |
| /* the accept callback for listen- and normal pcbs, if LWIP_CALLBACK_API */ \ |
| DEF_ACCEPT_CALLBACK \ |
| /* ports are in host byte order */ \ |
| u16_t local_port |
| |
| |
| /* the TCP protocol control block */ |
| struct tcp_pcb { |
| /** common PCB members */ |
| IP_PCB; |
| /** protocol specific PCB members */ |
| TCP_PCB_COMMON(struct tcp_pcb); |
| |
| /* ports are in host byte order */ |
| u16_t remote_port; |
| |
| u8_t flags; |
| #define TF_ACK_DELAY ((u8_t)0x01U) /* Delayed ACK. */ |
| #define TF_ACK_NOW ((u8_t)0x02U) /* Immediate ACK. */ |
| #define TF_INFR ((u8_t)0x04U) /* In fast recovery. */ |
| #define TF_TIMESTAMP ((u8_t)0x08U) /* Timestamp option enabled */ |
| #define TF_RXCLOSED ((u8_t)0x10U) /* rx closed by tcp_shutdown */ |
| #define TF_FIN ((u8_t)0x20U) /* Connection was closed locally (FIN segment enqueued). */ |
| #define TF_NODELAY ((u8_t)0x40U) /* Disable Nagle algorithm */ |
| #define TF_NAGLEMEMERR ((u8_t)0x80U) /* nagle enabled, memerr, try to output to prevent delayed ACK to happen */ |
| |
| /* the rest of the fields are in host byte order |
| as we have to do some math with them */ |
| /* receiver variables */ |
| u32_t rcv_nxt; /* next seqno expected */ |
| u16_t rcv_wnd; /* receiver window available */ |
| u16_t rcv_ann_wnd; /* receiver window to announce */ |
| u32_t rcv_ann_right_edge; /* announced right edge of window */ |
| |
| /* Timers */ |
| u32_t tmr; |
| u8_t polltmr, pollinterval; |
| |
| /* Retransmission timer. */ |
| s16_t rtime; |
| |
| u16_t mss; /* maximum segment size */ |
| |
| /* RTT (round trip time) estimation variables */ |
| u32_t rttest; /* RTT estimate in 500ms ticks */ |
| u32_t rtseq; /* sequence number being timed */ |
| s16_t sa, sv; /* @todo document this */ |
| |
| s16_t rto; /* retransmission time-out */ |
| u8_t nrtx; /* number of retransmissions */ |
| |
| /* fast retransmit/recovery */ |
| u32_t lastack; /* Highest acknowledged seqno. */ |
| u8_t dupacks; |
| |
| /* congestion avoidance/control variables */ |
| u16_t cwnd; |
| u16_t ssthresh; |
| |
| /* sender variables */ |
| u32_t snd_nxt; /* next new seqno to be sent */ |
| u16_t snd_wnd; /* sender window */ |
| u32_t snd_wl1, snd_wl2; /* Sequence and acknowledgement numbers of last |
| window update. */ |
| u32_t snd_lbb; /* Sequence number of next byte to be buffered. */ |
| |
| u16_t acked; |
| |
| u16_t snd_buf; /* Available buffer space for sending (in bytes). */ |
| #define TCP_SNDQUEUELEN_OVERFLOW (0xffffU-3) |
| u16_t snd_queuelen; /* Available buffer space for sending (in tcp_segs). */ |
| |
| #if TCP_OVERSIZE |
| /* Extra bytes available at the end of the last pbuf in unsent. */ |
| u16_t unsent_oversize; |
| #endif /* TCP_OVERSIZE */ |
| |
| /* These are ordered by sequence number: */ |
| struct tcp_seg *unsent; /* Unsent (queued) segments. */ |
| struct tcp_seg *unacked; /* Sent but unacknowledged segments. */ |
| #if TCP_QUEUE_OOSEQ |
| struct tcp_seg *ooseq; /* Received out of sequence segments. */ |
| #endif /* TCP_QUEUE_OOSEQ */ |
| |
| struct pbuf *refused_data; /* Data previously received but not yet taken by upper layer */ |
| |
| #if LWIP_CALLBACK_API |
| /* Function to be called when more send buffer space is available. */ |
| tcp_sent_fn sent; |
| /* Function to be called when (in-sequence) data has arrived. */ |
| tcp_recv_fn recv; |
| /* Function to be called when a connection has been set up. */ |
| tcp_connected_fn connected; |
| /* Function which is called periodically. */ |
| tcp_poll_fn poll; |
| /* Function to be called whenever a fatal error occurs. */ |
| tcp_err_fn errf; |
| #endif /* LWIP_CALLBACK_API */ |
| |
| #if LWIP_TCP_TIMESTAMPS |
| u32_t ts_lastacksent; |
| u32_t ts_recent; |
| #endif /* LWIP_TCP_TIMESTAMPS */ |
| |
| /* idle time before KEEPALIVE is sent */ |
| u32_t keep_idle; |
| #if LWIP_TCP_KEEPALIVE |
| u32_t keep_intvl; |
| u32_t keep_cnt; |
| #endif /* LWIP_TCP_KEEPALIVE */ |
| |
| /* Persist timer counter */ |
| u32_t persist_cnt; |
| /* Persist timer back-off */ |
| u8_t persist_backoff; |
| |
| /* KEEPALIVE counter */ |
| u8_t keep_cnt_sent; |
| }; |
| |
| struct tcp_pcb_listen { |
| /* Common members of all PCB types */ |
| IP_PCB; |
| /* Protocol specific PCB members */ |
| TCP_PCB_COMMON(struct tcp_pcb_listen); |
| |
| #if TCP_LISTEN_BACKLOG |
| u8_t backlog; |
| u8_t accepts_pending; |
| #endif /* TCP_LISTEN_BACKLOG */ |
| }; |
| |
| #if LWIP_EVENT_API |
| |
| enum lwip_event { |
| LWIP_EVENT_ACCEPT, |
| LWIP_EVENT_SENT, |
| LWIP_EVENT_RECV, |
| LWIP_EVENT_CONNECTED, |
| LWIP_EVENT_POLL, |
| LWIP_EVENT_ERR |
| }; |
| |
| err_t lwip_tcp_event(void *arg, struct tcp_pcb *pcb, |
| enum lwip_event, |
| struct pbuf *p, |
| u16_t size, |
| err_t err); |
| |
| #endif /* LWIP_EVENT_API */ |
| |
| /* Application program's interface: */ |
| struct tcp_pcb * tcp_new (void); |
| |
| void tcp_arg (struct tcp_pcb *pcb, void *arg); |
| void tcp_accept (struct tcp_pcb *pcb, tcp_accept_fn accept); |
| void tcp_recv (struct tcp_pcb *pcb, tcp_recv_fn recv); |
| void tcp_sent (struct tcp_pcb *pcb, tcp_sent_fn sent); |
| void tcp_poll (struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval); |
| void tcp_err (struct tcp_pcb *pcb, tcp_err_fn err); |
| |
| #define tcp_mss(pcb) (((pcb)->flags & TF_TIMESTAMP) ? ((pcb)->mss - 12) : (pcb)->mss) |
| #define tcp_sndbuf(pcb) ((pcb)->snd_buf) |
| #define tcp_sndqueuelen(pcb) ((pcb)->snd_queuelen) |
| #define tcp_nagle_disable(pcb) ((pcb)->flags |= TF_NODELAY) |
| #define tcp_nagle_enable(pcb) ((pcb)->flags &= ~TF_NODELAY) |
| #define tcp_nagle_disabled(pcb) (((pcb)->flags & TF_NODELAY) != 0) |
| |
| #if TCP_LISTEN_BACKLOG |
| #define tcp_accepted(pcb) do { \ |
| LWIP_ASSERT("pcb->state == LISTEN (called for wrong pcb?)", pcb->state == LISTEN); \ |
| (((struct tcp_pcb_listen *)(pcb))->accepts_pending--); } while(0) |
| #else /* TCP_LISTEN_BACKLOG */ |
| #define tcp_accepted(pcb) LWIP_ASSERT("pcb->state == LISTEN (called for wrong pcb?)", \ |
| pcb->state == LISTEN) |
| #endif /* TCP_LISTEN_BACKLOG */ |
| |
| void tcp_recved (struct tcp_pcb *pcb, u16_t len); |
| err_t tcp_bind (struct tcp_pcb *pcb, ip_addr_t *ipaddr, |
| u16_t port); |
| err_t tcp_connect (struct tcp_pcb *pcb, ip_addr_t *ipaddr, |
| u16_t port, tcp_connected_fn connected); |
| |
| struct tcp_pcb * tcp_listen_with_backlog(struct tcp_pcb *pcb, u8_t backlog); |
| #define tcp_listen(pcb) tcp_listen_with_backlog(pcb, TCP_DEFAULT_LISTEN_BACKLOG) |
| |
| void tcp_abort (struct tcp_pcb *pcb); |
| err_t tcp_close (struct tcp_pcb *pcb); |
| err_t tcp_shutdown(struct tcp_pcb *pcb, int shut_rx, int shut_tx); |
| |
| /* Flags for "apiflags" parameter in tcp_write */ |
| #define TCP_WRITE_FLAG_COPY 0x01 |
| #define TCP_WRITE_FLAG_MORE 0x02 |
| |
| err_t tcp_write (struct tcp_pcb *pcb, const void *dataptr, u16_t len, |
| u8_t apiflags); |
| |
| void tcp_setprio (struct tcp_pcb *pcb, u8_t prio); |
| |
| #define TCP_PRIO_MIN 1 |
| #define TCP_PRIO_NORMAL 64 |
| #define TCP_PRIO_MAX 127 |
| |
| err_t tcp_output (struct tcp_pcb *pcb); |
| |
| |
| const char* tcp_debug_state_str(enum tcp_state s); |
| |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* LWIP_TCP */ |
| |
| #endif /* __LWIP_TCP_H__ */ |