diff options
Diffstat (limited to 'firmware')
| -rw-r--r-- | firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c# | 981 |
1 files changed, 0 insertions, 981 deletions
diff --git a/firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c# b/firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c# deleted file mode 100644 index ca72d9dcc..000000000 --- a/firmware/zpu/lwip/lwip-1.3.1/src/core/#tcp_out.c# +++ /dev/null @@ -1,981 +0,0 @@ -/** - * @file - * Transmission Control Protocol, outgoing traffic - * - * The output functions of TCP. - * - */ - -/* - * 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> - * - */ - -#include "lwip/opt.h" - -#if LWIP_TCP /* don't build if not configured for use in lwipopts.h */ - -#include "lwip/tcp.h" -#include "lwip/def.h" -#include "lwip/mem.h" -#include "lwip/memp.h" -#include "lwip/sys.h" -#include "lwip/ip_addr.h" -#include "lwip/netif.h" -#include "lwip/inet.h" -#include "lwip/inet_chksum.h" -#include "lwip/stats.h" -#include "lwip/snmp.h" - -#include <string.h> - -/* Forward declarations.*/ -static void tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb); - -static struct tcp_hdr * -tcp_output_set_header(struct tcp_pcb *pcb, struct pbuf *p, int optlen, - u32_t seqno_be /* already in network byte order */) -{ - struct tcp_hdr *tcphdr = p->payload; - tcphdr->src = htons(pcb->local_port); - tcphdr->dest = htons(pcb->remote_port); - tcphdr->seqno = seqno_be; - tcphdr->ackno = htonl(pcb->rcv_nxt); - TCPH_FLAGS_SET(tcphdr, TCP_ACK); - tcphdr->wnd = htons(pcb->rcv_ann_wnd); - tcphdr->urgp = 0; - TCPH_HDRLEN_SET(tcphdr, (5 + optlen / 4)); - tcphdr->chksum = 0; - - /* If we're sending a packet, update the announced right window edge */ - pcb->rcv_ann_right_edge = pcb->rcv_nxt + pcb->rcv_ann_wnd; - - return tcphdr; -} - -/** - * Called by tcp_close() to send a segment including flags but not data. - * - * @param pcb the tcp_pcb over which to send a segment - * @param flags the flags to set in the segment header - * @return ERR_OK if sent, another err_t otherwise - */ -err_t -tcp_send_ctrl(struct tcp_pcb *pcb, u8_t flags) -{ - /* no data, no length, flags, copy=1, no optdata */ - return tcp_enqueue(pcb, NULL, 0, flags, TCP_WRITE_FLAG_COPY, 0); -} - -/** - * Write data for sending (but does not send it immediately). - * - * It waits in the expectation of more data being sent soon (as - * it can send them more efficiently by combining them together). - * To prompt the system to send data now, call tcp_output() after - * calling tcp_write(). - * - * @param pcb Protocol control block of the TCP connection to enqueue data for. - * @param data pointer to the data to send - * @param len length (in bytes) of the data to send - * @param apiflags combination of following flags : - * - TCP_WRITE_FLAG_COPY (0x01) data will be copied into memory belonging to the stack - * - TCP_WRITE_FLAG_MORE (0x02) for TCP connection, PSH flag will be set on last segment sent, - * @return ERR_OK if enqueued, another err_t on error - * - * @see tcp_write() - */ -err_t -tcp_write(struct tcp_pcb *pcb, const void *data, u16_t len, u8_t apiflags) -{ - LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_write(pcb=%p, data=%p, len=%"U16_F", apiflags=%"U16_F")\n", (void *)pcb, - data, len, (u16_t)apiflags)); - /* connection is in valid state for data transmission? */ - if (pcb->state == ESTABLISHED || - pcb->state == CLOSE_WAIT || - pcb->state == SYN_SENT || - pcb->state == SYN_RCVD) { - if (len > 0) { -#if LWIP_TCP_TIMESTAMPS - return tcp_enqueue(pcb, (void *)data, len, 0, apiflags, - pcb->flags & TF_TIMESTAMP ? TF_SEG_OPTS_TS : 0); -#else - return tcp_enqueue(pcb, (void *)data, len, 0, apiflags, 0); -#endif - } - return ERR_OK; - } else { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_STATE | 3, ("tcp_write() called in invalid state\n")); - return ERR_CONN; - } -} - -/** - * Enqueue data and/or TCP options for transmission - * - * Called by tcp_connect(), tcp_listen_input(), tcp_send_ctrl() and tcp_write(). - * - * @param pcb Protocol control block for the TCP connection to enqueue data for. - * @param arg Pointer to the data to be enqueued for sending. - * @param len Data length in bytes - * @param flags tcp header flags to set in the outgoing segment - * @param apiflags combination of following flags : - * - TCP_WRITE_FLAG_COPY (0x01) data will be copied into memory belonging to the stack - * - TCP_WRITE_FLAG_MORE (0x02) for TCP connection, PSH flag will be set on last segment sent, - * @param optflags options to include in segment later on (see definition of struct tcp_seg) - */ -err_t -tcp_enqueue(struct tcp_pcb *pcb, void *arg, u16_t len, - u8_t flags, u8_t apiflags, u8_t optflags) -{ - struct pbuf *p; - struct tcp_seg *seg, *useg, *queue; - u32_t seqno; - u16_t left, seglen; - void *ptr; - u16_t queuelen; - u8_t optlen; - - LWIP_DEBUGF(TCP_OUTPUT_DEBUG, - ("tcp_enqueue(pcb=%p, arg=%p, len=%"U16_F", flags=%"X16_F", apiflags=%"U16_F")\n", - (void *)pcb, arg, len, (u16_t)flags, (u16_t)apiflags)); - LWIP_ERROR("tcp_enqueue: packet needs payload, options, or SYN/FIN (programmer violates API)", - ((len != 0) || (optflags != 0) || ((flags & (TCP_SYN | TCP_FIN)) != 0)), - return ERR_ARG;); - LWIP_ERROR("tcp_enqueue: len != 0 || arg == NULL (programmer violates API)", - ((len != 0) || (arg == NULL)), return ERR_ARG;); - - /* fail on too much data */ - if (len > pcb->snd_buf) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_enqueue: too much data (len=%"U16_F" > snd_buf=%"U16_F")\n", len, pcb->snd_buf)); - pcb->flags |= TF_NAGLEMEMERR; - return ERR_MEM; - } - left = len; - ptr = arg; - - optlen = LWIP_TCP_OPT_LENGTH(optflags); - - /* seqno will be the sequence number of the first segment enqueued - * by the call to this function. */ - seqno = pcb->snd_lbb; - - LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_enqueue: queuelen: %"U16_F"\n", (u16_t)pcb->snd_queuelen)); - - /* If total number of pbufs on the unsent/unacked queues exceeds the - * configured maximum, return an error */ - queuelen = pcb->snd_queuelen; - /* check for configured max queuelen and possible overflow */ - if ((queuelen >= TCP_SND_QUEUELEN) || (queuelen > TCP_SNDQUEUELEN_OVERFLOW)) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 3, ("tcp_enqueue: too long queue %"U16_F" (max %"U16_F")\n", queuelen, TCP_SND_QUEUELEN)); - TCP_STATS_INC(tcp.memerr); - pcb->flags |= TF_NAGLEMEMERR; - return ERR_MEM; - } - if (queuelen != 0) { - LWIP_ASSERT("tcp_enqueue: pbufs on queue => at least one queue non-empty", - pcb->unacked != NULL || pcb->unsent != NULL); - } else { - LWIP_ASSERT("tcp_enqueue: no pbufs on queue => both queues empty", - pcb->unacked == NULL && pcb->unsent == NULL); - } - - /* First, break up the data into segments and tuck them together in - * the local "queue" variable. */ - useg = queue = seg = NULL; - seglen = 0; - while (queue == NULL || left > 0) { - /* The segment length (including options) should be at most the MSS */ - seglen = left > (pcb->mss - optlen) ? (pcb->mss - optlen) : left; - - /* Allocate memory for tcp_seg, and fill in fields. */ - seg = memp_malloc(MEMP_TCP_SEG); - if (seg == NULL) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, - ("tcp_enqueue: could not allocate memory for tcp_seg\n")); - goto memerr; - } - seg->next = NULL; - seg->p = NULL; - - /* first segment of to-be-queued data? */ - if (queue == NULL) { - queue = seg; - } - /* subsequent segments of to-be-queued data */ - else { - /* Attach the segment to the end of the queued segments */ - LWIP_ASSERT("useg != NULL", useg != NULL); - useg->next = seg; - } - /* remember last segment of to-be-queued data for next iteration */ - useg = seg; - - /* If copy is set, memory should be allocated - * and data copied into pbuf, otherwise data comes from - * ROM or other static memory, and need not be copied. */ - if (apiflags & TCP_WRITE_FLAG_COPY) { - if ((seg->p = pbuf_alloc(PBUF_TRANSPORT, seglen + optlen, PBUF_RAM)) == NULL) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, - ("tcp_enqueue : could not allocate memory for pbuf copy size %"U16_F"\n", seglen)); - goto memerr; - } - LWIP_ASSERT("check that first pbuf can hold the complete seglen", - (seg->p->len >= seglen + optlen)); - queuelen += pbuf_clen(seg->p); - if (arg != NULL) { - MEMCPY((char *)seg->p->payload + optlen, ptr, seglen); - } - seg->dataptr = seg->p->payload; - } - /* do not copy data */ - else { - /* First, allocate a pbuf for the headers. */ - if ((seg->p = pbuf_alloc(PBUF_TRANSPORT, optlen, PBUF_RAM)) == NULL) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, - ("tcp_enqueue: could not allocate memory for header pbuf\n")); - goto memerr; - } - queuelen += pbuf_clen(seg->p); - - /* Second, allocate a pbuf for holding the data. - * since the referenced data is available at least until it is sent out on the - * link (as it has to be ACKed by the remote party) we can safely use PBUF_ROM - * instead of PBUF_REF here. - */ - if (left > 0) { - if ((p = pbuf_alloc(PBUF_RAW, seglen, PBUF_ROM)) == NULL) { - /* If allocation fails, we have to deallocate the header pbuf as well. */ - pbuf_free(seg->p); - seg->p = NULL; - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, - ("tcp_enqueue: could not allocate memory for zero-copy pbuf\n")); - goto memerr; - } - ++queuelen; - /* reference the non-volatile payload data */ - p->payload = ptr; - seg->dataptr = ptr; - - /* Concatenate the headers and data pbufs together. */ - pbuf_cat(seg->p/*header*/, p/*data*/); - p = NULL; - } - } - - /* Now that there are more segments queued, we check again if the - length of the queue exceeds the configured maximum or overflows. */ - if ((queuelen > TCP_SND_QUEUELEN) || (queuelen > TCP_SNDQUEUELEN_OVERFLOW)) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_enqueue: queue too long %"U16_F" (%"U16_F")\n", queuelen, TCP_SND_QUEUELEN)); - goto memerr; - } - - seg->len = seglen; - - /* build TCP header */ - if (pbuf_header(seg->p, TCP_HLEN)) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | 2, ("tcp_enqueue: no room for TCP header in pbuf.\n")); - TCP_STATS_INC(tcp.err); - goto memerr; - } - seg->tcphdr = seg->p->payload; - seg->tcphdr->src = htons(pcb->local_port); - seg->tcphdr->dest = htons(pcb->remote_port); - seg->tcphdr->seqno = htonl(seqno); - seg->tcphdr->urgp = 0; - TCPH_FLAGS_SET(seg->tcphdr, flags); - /* don't fill in tcphdr->ackno and tcphdr->wnd until later */ - - seg->flags = optflags; - - /* Set the length of the header */ - TCPH_HDRLEN_SET(seg->tcphdr, (5 + optlen / 4)); - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_TRACE, ("tcp_enqueue: queueing %"U32_F":%"U32_F" (0x%"X16_F")\n", - ntohl(seg->tcphdr->seqno), - ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg), - (u16_t)flags)); - - left -= seglen; - seqno += seglen; - ptr = (void *)((u8_t *)ptr + seglen); - } - - /* Now that the data to be enqueued has been broken up into TCP - segments in the queue variable, we add them to the end of the - pcb->unsent queue. */ - if (pcb->unsent == NULL) { - useg = NULL; - } - else { - for (useg = pcb->unsent; useg->next != NULL; useg = useg->next); - } - /* { useg is last segment on the unsent queue, NULL if list is empty } */ - - /* If there is room in the last pbuf on the unsent queue, - chain the first pbuf on the queue together with that. */ - if (useg != NULL && - TCP_TCPLEN(useg) != 0 && - !(TCPH_FLAGS(useg->tcphdr) & (TCP_SYN | TCP_FIN)) && - !(flags & (TCP_SYN | TCP_FIN)) && - /* fit within max seg size */ - (useg->len + queue->len <= pcb->mss) && - /* only concatenate segments with the same options */ - (useg->flags == queue->flags)) { - /* Remove TCP header from first segment of our to-be-queued list */ - if(pbuf_header(queue->p, -(TCP_HLEN + optlen))) { - /* Can we cope with this failing? Just assert for now */ - LWIP_ASSERT("pbuf_header failed\n", 0); - TCP_STATS_INC(tcp.err); - goto memerr; - } - if (queue->p->len == 0) { - /* free the first (header-only) pbuf if it is now empty (contained only headers) */ - struct pbuf *old_q = queue->p; - queue->p = queue->p->next; - old_q->next = NULL; - queuelen--; - pbuf_free(old_q); - } - LWIP_ASSERT("zero-length pbuf", (queue->p != NULL) && (queue->p->len > 0)); - pbuf_cat(useg->p, queue->p); - useg->len += queue->len; - useg->next = queue->next; - - LWIP_DEBUGF(TCP_OUTPUT_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("tcp_enqueue: chaining segments, new len %"U16_F"\n", useg->len)); - if (seg == queue) { - seg = useg; - seglen = useg->len; - } - memp_free(MEMP_TCP_SEG, queue); - } - else { - /* empty list */ - if (useg == NULL) { - /* initialize list with this segment */ - pcb->unsent = queue; - } - /* enqueue segment */ - else { - useg->next = queue; - } - } - if ((flags & TCP_SYN) || (flags & TCP_FIN)) { - ++len; - } - if (flags & TCP_FIN) { - pcb->flags |= TF_FIN; - } - pcb->snd_lbb += len; - - pcb->snd_buf -= len; - - /* update number of segments on the queues */ - pcb->snd_queuelen = queuelen; - LWIP_DEBUGF(TCP_QLEN_DEBUG, ("tcp_enqueue: %"S16_F" (after enqueued)\n", pcb->snd_queuelen)); - if (pcb->snd_queuelen != 0) { - LWIP_ASSERT("tcp_enqueue: valid queue length", - pcb->unacked != NULL || pcb->unsent != NULL); - } - - /* Set the PSH flag in the last segment that we enqueued, but only - if the segment has data (indicated by seglen > 0). */ - if (seg != NULL && seglen > 0 && seg->tcphdr != NULL && ((apiflags & TCP_WRITE_FLAG_MORE)==0)) { - TCPH_SET_FLAG(seg->tcphdr, TCP_PSH); - } - - return ERR_OK; -memerr: - pcb->flags |= TF_NAGLEMEMERR; - TCP_STATS_INC(tcp.memerr); - - if (queue != NULL) { - tcp_segs_free(queue); - } - if (pcb->snd_queuelen != 0) { - LWIP_ASSERT("tcp_enqueue: valid queue length", pcb->unacked != NULL || - pcb->unsent != NULL); - } - LWIP_DEBUGF(TCP_QLEN_DEBUG | LWIP_DBG_STATE, ("tcp_enqueue: %"S16_F" (with mem err)\n", pcb->snd_queuelen)); - return ERR_MEM; -} - - -#if LWIP_TCP_TIMESTAMPS -/* Build a timestamp option (12 bytes long) at the specified options pointer) - * - * @param pcb tcp_pcb - * @param opts option pointer where to store the timestamp option - */ -static void -tcp_build_timestamp_option(struct tcp_pcb *pcb, u32_t *opts) -{ - /* Pad with two NOP options to make everything nicely aligned */ - opts[0] = htonl(0x0101080A); - opts[1] = htonl(sys_now()); - opts[2] = htonl(pcb->ts_recent); -} -#endif - - -/** - * Find out what we can send and send it - * - * @param pcb Protocol control block for the TCP connection to send data - * @return ERR_OK if data has been sent or nothing to send - * another err_t on error - */ -err_t -tcp_output(struct tcp_pcb *pcb) -{ - struct pbuf *p; - struct tcp_hdr *tcphdr; - struct tcp_seg *seg, *useg; - u32_t wnd, snd_nxt; -#if TCP_CWND_DEBUG - s16_t i = 0; -#endif /* TCP_CWND_DEBUG */ - u8_t optlen = 0; - - /* First, check if we are invoked by the TCP input processing - code. If so, we do not output anything. Instead, we rely on the - input processing code to call us when input processing is done - with. */ - if (tcp_input_pcb == pcb) { - return ERR_OK; - } - - wnd = LWIP_MIN(pcb->snd_wnd, pcb->cwnd); - - seg = pcb->unsent; - - /* useg should point to last segment on unacked queue */ - useg = pcb->unacked; - if (useg != NULL) { - for (; useg->next != NULL; useg = useg->next); - } - - /* If the TF_ACK_NOW flag is set and no data will be sent (either - * because the ->unsent queue is empty or because the window does - * not allow it), construct an empty ACK segment and send it. - * - * If data is to be sent, we will just piggyback the ACK (see below). - */ - if (pcb->flags & TF_ACK_NOW && - (seg == NULL || - ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len > wnd)) { -#if LWIP_TCP_TIMESTAMPS - if (pcb->flags & TF_TIMESTAMP) - optlen = LWIP_TCP_OPT_LENGTH(TF_SEG_OPTS_TS); -#endif - p = pbuf_alloc(PBUF_IP, TCP_HLEN + optlen, PBUF_RAM); - if (p == NULL) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: (ACK) could not allocate pbuf\n")); - return ERR_BUF; - } - LWIP_DEBUGF(TCP_OUTPUT_DEBUG, - ("tcp_output: sending ACK for %"U32_F"\n", pcb->rcv_nxt)); - /* remove ACK flags from the PCB, as we send an empty ACK now */ - pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW); - - tcphdr = tcp_output_set_header(pcb, p, optlen, htonl(pcb->snd_nxt)); - - /* NB. MSS option is only sent on SYNs, so ignore it here */ -#if LWIP_TCP_TIMESTAMPS - pcb->ts_lastacksent = pcb->rcv_nxt; - - if (pcb->flags & TF_TIMESTAMP) - tcp_build_timestamp_option(pcb, (u32_t *)(tcphdr + 1)); -#endif - -#if CHECKSUM_GEN_TCP - tcphdr->chksum = inet_chksum_pseudo(p, &(pcb->local_ip), &(pcb->remote_ip), - IP_PROTO_TCP, p->tot_len); -#endif -#if LWIP_NETIF_HWADDRHINT - ip_output_hinted(p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos, - IP_PROTO_TCP, &(pcb->addr_hint)); -#else /* LWIP_NETIF_HWADDRHINT*/ - ip_output(p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos, - IP_PROTO_TCP); -#endif /* LWIP_NETIF_HWADDRHINT*/ - pbuf_free(p); - - return ERR_OK; - } - -#if TCP_OUTPUT_DEBUG - if (seg == NULL) { - LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output: nothing to send (%p)\n", - (void*)pcb->unsent)); - } -#endif /* TCP_OUTPUT_DEBUG */ -#if TCP_CWND_DEBUG - if (seg == NULL) { - LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_output: snd_wnd %"U16_F - ", cwnd %"U16_F", wnd %"U32_F - ", seg == NULL, ack %"U32_F"\n", - pcb->snd_wnd, pcb->cwnd, wnd, pcb->lastack)); - } else { - LWIP_DEBUGF(TCP_CWND_DEBUG, - ("tcp_output: snd_wnd %"U16_F", cwnd %"U16_F", wnd %"U32_F - ", effwnd %"U32_F", seq %"U32_F", ack %"U32_F"\n", - pcb->snd_wnd, pcb->cwnd, wnd, - ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len, - ntohl(seg->tcphdr->seqno), pcb->lastack)); - } -#endif /* TCP_CWND_DEBUG */ - /* data available and window allows it to be sent? */ - while (seg != NULL && - ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len <= wnd) { - LWIP_ASSERT("RST not expected here!", - (TCPH_FLAGS(seg->tcphdr) & TCP_RST) == 0); - /* Stop sending if the nagle algorithm would prevent it - * Don't stop: - * - if tcp_enqueue had a memory error before (prevent delayed ACK timeout) or - * - if FIN was already enqueued for this PCB (SYN is always alone in a segment - - * either seg->next != NULL or pcb->unacked == NULL; - * RST is no sent using tcp_enqueue/tcp_output. - */ - if((tcp_do_output_nagle(pcb) == 0) && - ((pcb->flags & (TF_NAGLEMEMERR | TF_FIN)) == 0)){ - break; - } -#if TCP_CWND_DEBUG - LWIP_DEBUGF(TCP_CWND_DEBUG, ("tcp_output: snd_wnd %"U16_F", cwnd %"U16_F", wnd %"U32_F", effwnd %"U32_F", seq %"U32_F", ack %"U32_F", i %"S16_F"\n", - pcb->snd_wnd, pcb->cwnd, wnd, - ntohl(seg->tcphdr->seqno) + seg->len - - pcb->lastack, - ntohl(seg->tcphdr->seqno), pcb->lastack, i)); - ++i; -#endif /* TCP_CWND_DEBUG */ - - pcb->unsent = seg->next; - - if (pcb->state != SYN_SENT) { - TCPH_SET_FLAG(seg->tcphdr, TCP_ACK); - pcb->flags &= ~(TF_ACK_DELAY | TF_ACK_NOW); - } - - tcp_output_segment(seg, pcb); - snd_nxt = ntohl(seg->tcphdr->seqno) + TCP_TCPLEN(seg); - if (TCP_SEQ_LT(pcb->snd_nxt, snd_nxt)) { - pcb->snd_nxt = snd_nxt; - } - /* put segment on unacknowledged list if length > 0 */ - if (TCP_TCPLEN(seg) > 0) { - seg->next = NULL; - /* unacked list is empty? */ - if (pcb->unacked == NULL) { - pcb->unacked = seg; - useg = seg; - /* unacked list is not empty? */ - } else { - /* In the case of fast retransmit, the packet should not go to the tail - * of the unacked queue, but rather somewhere before it. We need to check for - * this case. -STJ Jul 27, 2004 */ - if (TCP_SEQ_LT(ntohl(seg->tcphdr->seqno), ntohl(useg->tcphdr->seqno))){ - /* add segment to before tail of unacked list, keeping the list sorted */ - struct tcp_seg **cur_seg = &(pcb->unacked); - while (*cur_seg && - TCP_SEQ_LT(ntohl((*cur_seg)->tcphdr->seqno), ntohl(seg->tcphdr->seqno))) { - cur_seg = &((*cur_seg)->next ); - } - seg->next = (*cur_seg); - (*cur_seg) = seg; - } else { - /* add segment to tail of unacked list */ - useg->next = seg; - useg = useg->next; - } - } - /* do not queue empty segments on the unacked list */ - } else { - tcp_seg_free(seg); - } - seg = pcb->unsent; - } - - if (seg != NULL && pcb->persist_backoff == 0 && - ntohl(seg->tcphdr->seqno) - pcb->lastack + seg->len > pcb->snd_wnd) { - /* prepare for persist timer */ - pcb->persist_cnt = 0; - pcb->persist_backoff = 1; - } - - pcb->flags &= ~TF_NAGLEMEMERR; - return ERR_OK; -} - -/** - * Called by tcp_output() to actually send a TCP segment over IP. - * - * @param seg the tcp_seg to send - * @param pcb the tcp_pcb for the TCP connection used to send the segment - */ -static void -tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb) -{ - u16_t len; - struct netif *netif; - u32_t *opts; - - /** @bug Exclude retransmitted segments from this count. */ - snmp_inc_tcpoutsegs(); - - /* The TCP header has already been constructed, but the ackno and - wnd fields remain. */ - seg->tcphdr->ackno = htonl(pcb->rcv_nxt); - - /* advertise our receive window size in this TCP segment */ - seg->tcphdr->wnd = htons(pcb->rcv_ann_wnd); - - pcb->rcv_ann_right_edge = pcb->rcv_nxt + pcb->rcv_ann_wnd; - - /* Add any requested options. NB MSS option is only set on SYN - packets, so ignore it here */ - opts = (u32_t *)(seg->tcphdr + 1); - if (seg->flags & TF_SEG_OPTS_MSS) { - TCP_BUILD_MSS_OPTION(*opts); - opts += 1; - } -#if LWIP_TCP_TIMESTAMPS - pcb->ts_lastacksent = pcb->rcv_nxt; - - if (seg->flags & TF_SEG_OPTS_TS) { - tcp_build_timestamp_option(pcb, opts); - opts += 3; - } -#endif - - /* If we don't have a local IP address, we get one by - calling ip_route(). */ - if (ip_addr_isany(&(pcb->local_ip))) { - netif = ip_route(&(pcb->remote_ip)); - if (netif == NULL) { - return; - } - ip_addr_set(&(pcb->local_ip), &(netif->ip_addr)); - } - - /* Set retransmission timer running if it is not currently enabled */ - if(pcb->rtime == -1) - pcb->rtime = 0; - - if (pcb->rttest == 0) { - pcb->rttest = tcp_ticks; - pcb->rtseq = ntohl(seg->tcphdr->seqno); - - LWIP_DEBUGF(TCP_RTO_DEBUG, ("tcp_output_segment: rtseq %"U32_F"\n", pcb->rtseq)); - } - LWIP_DEBUGF(TCP_OUTPUT_DEBUG, ("tcp_output_segment: %"U32_F":%"U32_F"\n", - htonl(seg->tcphdr->seqno), htonl(seg->tcphdr->seqno) + - seg->len)); - - len = (u16_t)((u8_t *)seg->tcphdr - (u8_t *)seg->p->payload); - - seg->p->len -= len; - seg->p->tot_len -= len; - - seg->p->payload = seg->tcphdr; - - seg->tcphdr->chksum = 0; -#if CHECKSUM_GEN_TCP - seg->tcphdr->chksum = inet_chksum_pseudo(seg->p, - &(pcb->local_ip), - &(pcb->remote_ip), - IP_PROTO_TCP, seg->p->tot_len); -#endif - TCP_STATS_INC(tcp.xmit); - -#if LWIP_NETIF_HWADDRHINT - ip_output_hinted(seg->p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos, - IP_PROTO_TCP, &(pcb->addr_hint)); -#else /* LWIP_NETIF_HWADDRHINT*/ - ip_output(seg->p, &(pcb->local_ip), &(pcb->remote_ip), pcb->ttl, pcb->tos, - IP_PROTO_TCP); -#endif /* LWIP_NETIF_HWADDRHINT*/ -} - -/** - * Send a TCP RESET packet (empty segment with RST flag set) either to - * abort a connection or to show that there is no matching local connection - * for a received segment. - * - * Called by tcp_abort() (to abort a local connection), tcp_input() (if no - * matching local pcb was found), tcp_listen_input() (if incoming segment - * has ACK flag set) and tcp_process() (received segment in the wrong state) - * - * Since a RST segment is in most cases not sent for an active connection, - * tcp_rst() has a number of arguments that are taken from a tcp_pcb for - * most other segment output functions. - * - * @param seqno the sequence number to use for the outgoing segment - * @param ackno the acknowledge number to use for the outgoing segment - * @param local_ip the local IP address to send the segment from - * @param remote_ip the remote IP address to send the segment to - * @param local_port the local TCP port to send the segment from - * @param remote_port the remote TCP port to send the segment to - */ -void -tcp_rst(u32_t seqno, u32_t ackno, - struct ip_addr *local_ip, struct ip_addr *remote_ip, - u16_t local_port, u16_t remote_port) -{ - struct pbuf *p; - struct tcp_hdr *tcphdr; - p = pbuf_alloc(PBUF_IP, TCP_HLEN, PBUF_RAM); - if (p == NULL) { - LWIP_DEBUGF(TCP_DEBUG, ("tcp_rst: could not allocate memory for pbuf\n")); - return; - } - LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr", - (p->len >= sizeof(struct tcp_hdr))); - - tcphdr = p->payload; - tcphdr->src = htons(local_port); - tcphdr->dest = htons(remote_port); - tcphdr->seqno = htonl(seqno); - tcphdr->ackno = htonl(ackno); - TCPH_FLAGS_SET(tcphdr, TCP_RST | TCP_ACK); - tcphdr->wnd = htons(TCP_WND); - tcphdr->urgp = 0; - TCPH_HDRLEN_SET(tcphdr, 5); - - tcphdr->chksum = 0; -#if CHECKSUM_GEN_TCP - tcphdr->chksum = inet_chksum_pseudo(p, local_ip, remote_ip, - IP_PROTO_TCP, p->tot_len); -#endif - TCP_STATS_INC(tcp.xmit); - snmp_inc_tcpoutrsts(); - /* Send output with hardcoded TTL since we have no access to the pcb */ - ip_output(p, local_ip, remote_ip, TCP_TTL, 0, IP_PROTO_TCP); - pbuf_free(p); - LWIP_DEBUGF(TCP_RST_DEBUG, ("tcp_rst: seqno %"U32_F" ackno %"U32_F".\n", seqno, ackno)); -} - -/** - * Requeue all unacked segments for retransmission - * - * Called by tcp_slowtmr() for slow retransmission. - * - * @param pcb the tcp_pcb for which to re-enqueue all unacked segments - */ -void -tcp_rexmit_rto(struct tcp_pcb *pcb) -{ - struct tcp_seg *seg; - - if (pcb->unacked == NULL) { - return; - } - - /* Move all unacked segments to the head of the unsent queue */ - for (seg = pcb->unacked; seg->next != NULL; seg = seg->next); - /* concatenate unsent queue after unacked queue */ - seg->next = pcb->unsent; - /* unsent queue is the concatenated queue (of unacked, unsent) */ - pcb->unsent = pcb->unacked; - /* unacked queue is now empty */ - pcb->unacked = NULL; - - /* increment number of retransmissions */ - ++pcb->nrtx; - - /* Don't take any RTT measurements after retransmitting. */ - pcb->rttest = 0; - - /* Do the actual retransmission */ - tcp_output(pcb); -} - -/** - * Requeue the first unacked segment for retransmission - * - * Called by tcp_receive() for fast retramsmit. - * - * @param pcb the tcp_pcb for which to retransmit the first unacked segment - */ -void -tcp_rexmit(struct tcp_pcb *pcb) -{ - struct tcp_seg *seg; - struct tcp_seg **cur_seg; - - if (pcb->unacked == NULL) { - return; - } - - /* Move the first unacked segment to the unsent queue */ - /* Keep the unsent queue sorted. */ - seg = pcb->unacked; - pcb->unacked = seg->next; - - cur_seg = &(pcb->unsent); - while (*cur_seg && - TCP_SEQ_LT(ntohl((*cur_seg)->tcphdr->seqno), ntohl(seg->tcphdr->seqno))) { - cur_seg = &((*cur_seg)->next ); - } - seg->next = *cur_seg; - *cur_seg = seg; - - ++pcb->nrtx; - - /* Don't take any rtt measurements after retransmitting. */ - pcb->rttest = 0; - - /* Do the actual retransmission. */ - snmp_inc_tcpretranssegs(); - tcp_output(pcb); -} - -/** - * Send keepalive packets to keep a connection active although - * no data is sent over it. - * - * Called by tcp_slowtmr() - * - * @param pcb the tcp_pcb for which to send a keepalive packet - */ -void -tcp_keepalive(struct tcp_pcb *pcb) -{ - struct pbuf *p; - struct tcp_hdr *tcphdr; - - LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: sending KEEPALIVE probe to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1(&pcb->remote_ip), ip4_addr2(&pcb->remote_ip), - ip4_addr3(&pcb->remote_ip), ip4_addr4(&pcb->remote_ip))); - - LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: tcp_ticks %"U32_F" pcb->tmr %"U32_F" pcb->keep_cnt_sent %"U16_F"\n", - tcp_ticks, pcb->tmr, pcb->keep_cnt_sent)); - - p = pbuf_alloc(PBUF_IP, TCP_HLEN, PBUF_RAM); - - if(p == NULL) { - LWIP_DEBUGF(TCP_DEBUG, - ("tcp_keepalive: could not allocate memory for pbuf\n")); - return; - } - LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr", - (p->len >= sizeof(struct tcp_hdr))); - - tcphdr = tcp_output_set_header(pcb, p, 0, htonl(pcb->snd_nxt - 1)); - -#if CHECKSUM_GEN_TCP - tcphdr->chksum = inet_chksum_pseudo(p, &pcb->local_ip, &pcb->remote_ip, - IP_PROTO_TCP, p->tot_len); -#endif - TCP_STATS_INC(tcp.xmit); - - /* Send output to IP */ -#if LWIP_NETIF_HWADDRHINT - ip_output_hinted(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP, - &(pcb->addr_hint)); -#else /* LWIP_NETIF_HWADDRHINT*/ - ip_output(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP); -#endif /* LWIP_NETIF_HWADDRHINT*/ - - pbuf_free(p); - - LWIP_DEBUGF(TCP_DEBUG, ("tcp_keepalive: seqno %"U32_F" ackno %"U32_F".\n", - pcb->snd_nxt - 1, pcb->rcv_nxt)); -} - - -/** - * Send persist timer zero-window probes to keep a connection active - * when a window update is lost. - * - * Called by tcp_slowtmr() - * - * @param pcb the tcp_pcb for which to send a zero-window probe packet - */ -void -tcp_zero_window_probe(struct tcp_pcb *pcb) -{ - struct pbuf *p; - struct tcp_hdr *tcphdr; - struct tcp_seg *seg; - - LWIP_DEBUGF(TCP_DEBUG, - ("tcp_zero_window_probe: sending ZERO WINDOW probe to %" - U16_F".%"U16_F".%"U16_F".%"U16_F"\n", - ip4_addr1(&pcb->remote_ip), ip4_addr2(&pcb->remote_ip), - ip4_addr3(&pcb->remote_ip), ip4_addr4(&pcb->remote_ip))); - - LWIP_DEBUGF(TCP_DEBUG, - ("tcp_zero_window_probe: tcp_ticks %"U32_F - " pcb->tmr %"U32_F" pcb->keep_cnt_sent %"U16_F"\n", - tcp_ticks, pcb->tmr, pcb->keep_cnt_sent)); - - seg = pcb->unacked; - - if(seg == NULL) - seg = pcb->unsent; - - if(seg == NULL) - return; - - p = pbuf_alloc(PBUF_IP, TCP_HLEN + 1, PBUF_RAM); - - if(p == NULL) { - LWIP_DEBUGF(TCP_DEBUG, ("tcp_zero_window_probe: no memory for pbuf\n")); - return; - } - LWIP_ASSERT("check that first pbuf can hold struct tcp_hdr", - (p->len >= sizeof(struct tcp_hdr))); - - tcphdr = tcp_output_set_header(pcb, p, 0, seg->tcphdr->seqno); - - /* Copy in one byte from the head of the unacked queue */ - *((char *)p->payload + sizeof(struct tcp_hdr)) = *(char *)seg->dataptr; - -#if CHECKSUM_GEN_TCP - tcphdr->chksum = inet_chksum_pseudo(p, &pcb->local_ip, &pcb->remote_ip, - IP_PROTO_TCP, p->tot_len); -#endif - TCP_STATS_INC(tcp.xmit); - - /* Send output to IP */ -#if LWIP_NETIF_HWADDRHINT - ip_output_hinted(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP, - &(pcb->addr_hint)); -#else /* LWIP_NETIF_HWADDRHINT*/ - ip_output(p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl, 0, IP_PROTO_TCP); -#endif /* LWIP_NETIF_HWADDRHINT*/ - - pbuf_free(p); - - LWIP_DEBUGF(TCP_DEBUG, ("tcp_zero_window_probe: seqno %"U32_F - " ackno %"U32_F".\n", - pcb->snd_nxt - 1, pcb->rcv_nxt)); -} -#endif /* LWIP_TCP */ |