source: mainline/uspace/srv/net/tcp/tqueue.c@ 1ede059

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 1ede059 was 2f19103, checked in by Jiri Svoboda <jiri@…>, 10 years ago

TCP and UDP servers can make use of inet/endpoint.h types internally.
  • Property mode set to 100644
File size: 9.9 KB
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1/*
2 * Copyright (c) 2015 Jiri Svoboda
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup tcp
30 * @{
31 */
32
33/**
34 * @file TCP transmission queue
35 */
36
37#include <adt/list.h>
38#include <errno.h>
39#include <fibril_synch.h>
40#include <byteorder.h>
41#include <io/log.h>
42#include <macros.h>
43#include <mem.h>
44#include <stdlib.h>
45#include "conn.h"
46#include "ncsim.h"
47#include "pdu.h"
48#include "rqueue.h"
49#include "segment.h"
50#include "seq_no.h"
51#include "tqueue.h"
52#include "tcp.h"
53#include "tcp_type.h"
54
55#define RETRANSMIT_TIMEOUT (2*1000*1000)
56
57static void retransmit_timeout_func(void *arg);
58static void tcp_tqueue_timer_set(tcp_conn_t *conn);
59static void tcp_tqueue_timer_clear(tcp_conn_t *conn);
60
61int tcp_tqueue_init(tcp_tqueue_t *tqueue, tcp_conn_t *conn)
62{
63 tqueue->conn = conn;
64 tqueue->timer = fibril_timer_create(&conn->lock);
65 if (tqueue->timer == NULL)
66 return ENOMEM;
67
68 list_initialize(&tqueue->list);
69
70 return EOK;
71}
72
73void tcp_tqueue_clear(tcp_tqueue_t *tqueue)
74{
75 tcp_tqueue_timer_clear(tqueue->conn);
76}
77
78void tcp_tqueue_fini(tcp_tqueue_t *tqueue)
79{
80 if (tqueue->timer != NULL) {
81 fibril_timer_destroy(tqueue->timer);
82 tqueue->timer = NULL;
83 }
84}
85
86void tcp_tqueue_ctrl_seg(tcp_conn_t *conn, tcp_control_t ctrl)
87{
88 tcp_segment_t *seg;
89
90 log_msg(LOG_DEFAULT, LVL_DEBUG, "tcp_tqueue_ctrl_seg(%p, %u)", conn, ctrl);
91
92 seg = tcp_segment_make_ctrl(ctrl);
93 tcp_tqueue_seg(conn, seg);
94 tcp_segment_delete(seg);
95}
96
97void tcp_tqueue_seg(tcp_conn_t *conn, tcp_segment_t *seg)
98{
99 tcp_segment_t *rt_seg;
100 tcp_tqueue_entry_t *tqe;
101
102 log_msg(LOG_DEFAULT, LVL_DEBUG, "%s: tcp_tqueue_seg(%p, %p)", conn->name, conn,
103 seg);
104
105 /*
106 * Add segment to retransmission queue
107 */
108
109 if (seg->len > 0) {
110 rt_seg = tcp_segment_dup(seg);
111 if (rt_seg == NULL) {
112 log_msg(LOG_DEFAULT, LVL_ERROR, "Memory allocation failed.");
113 /* XXX Handle properly */
114 return;
115 }
116
117 tqe = calloc(1, sizeof(tcp_tqueue_entry_t));
118 if (tqe == NULL) {
119 log_msg(LOG_DEFAULT, LVL_ERROR, "Memory allocation failed.");
120 /* XXX Handle properly */
121 return;
122 }
123
124 tqe->conn = conn;
125 tqe->seg = rt_seg;
126 rt_seg->seq = conn->snd_nxt;
127
128 list_append(&tqe->link, &conn->retransmit.list);
129
130 /* Set retransmission timer */
131 tcp_tqueue_timer_set(conn);
132 }
133
134 tcp_prepare_transmit_segment(conn, seg);
135}
136
137void tcp_prepare_transmit_segment(tcp_conn_t *conn, tcp_segment_t *seg)
138{
139 /*
140 * Always send ACK once we have received SYN, except for RST segments.
141 * (Spec says we should always send ACK once connection has been
142 * established.)
143 */
144 if (tcp_conn_got_syn(conn) && (seg->ctrl & CTL_RST) == 0)
145 seg->ctrl |= CTL_ACK;
146
147 seg->seq = conn->snd_nxt;
148 conn->snd_nxt += seg->len;
149
150 tcp_conn_transmit_segment(conn, seg);
151}
152
153/** Transmit data from the send buffer.
154 *
155 * @param conn Connection
156 */
157void tcp_tqueue_new_data(tcp_conn_t *conn)
158{
159 size_t avail_wnd;
160 size_t xfer_seqlen;
161 size_t snd_buf_seqlen;
162 size_t data_size;
163 tcp_control_t ctrl;
164 bool send_fin;
165
166 tcp_segment_t *seg;
167
168 log_msg(LOG_DEFAULT, LVL_DEBUG, "%s: tcp_tqueue_new_data()", conn->name);
169
170 /* Number of free sequence numbers in send window */
171 avail_wnd = (conn->snd_una + conn->snd_wnd) - conn->snd_nxt;
172 snd_buf_seqlen = conn->snd_buf_used + (conn->snd_buf_fin ? 1 : 0);
173
174 xfer_seqlen = min(snd_buf_seqlen, avail_wnd);
175 log_msg(LOG_DEFAULT, LVL_DEBUG, "%s: snd_buf_seqlen = %zu, SND.WND = %" PRIu32 ", "
176 "xfer_seqlen = %zu", conn->name, snd_buf_seqlen, conn->snd_wnd,
177 xfer_seqlen);
178
179 if (xfer_seqlen == 0)
180 return;
181
182 /* XXX Do not always send immediately */
183
184 send_fin = conn->snd_buf_fin && xfer_seqlen == snd_buf_seqlen;
185 data_size = xfer_seqlen - (send_fin ? 1 : 0);
186
187 if (send_fin) {
188 log_msg(LOG_DEFAULT, LVL_DEBUG, "%s: Sending out FIN.", conn->name);
189 /* We are sending out FIN */
190 ctrl = CTL_FIN;
191 } else {
192 ctrl = 0;
193 }
194
195 seg = tcp_segment_make_data(ctrl, conn->snd_buf, data_size);
196 if (seg == NULL) {
197 log_msg(LOG_DEFAULT, LVL_ERROR, "Memory allocation failure.");
198 return;
199 }
200
201 /* Remove data from send buffer */
202 memmove(conn->snd_buf, conn->snd_buf + data_size,
203 conn->snd_buf_used - data_size);
204 conn->snd_buf_used -= data_size;
205
206 if (send_fin)
207 conn->snd_buf_fin = false;
208
209 fibril_condvar_broadcast(&conn->snd_buf_cv);
210
211 if (send_fin)
212 tcp_conn_fin_sent(conn);
213
214 tcp_tqueue_seg(conn, seg);
215 tcp_segment_delete(seg);
216}
217
218/** Remove ACKed segments from retransmission queue and possibly transmit
219 * more data.
220 *
221 * This should be called when SND.UNA is updated due to incoming ACK.
222 */
223void tcp_tqueue_ack_received(tcp_conn_t *conn)
224{
225 link_t *cur, *next;
226
227 log_msg(LOG_DEFAULT, LVL_DEBUG, "%s: tcp_tqueue_ack_received(%p)", conn->name,
228 conn);
229
230 cur = conn->retransmit.list.head.next;
231
232 while (cur != &conn->retransmit.list.head) {
233 next = cur->next;
234
235 tcp_tqueue_entry_t *tqe = list_get_instance(cur,
236 tcp_tqueue_entry_t, link);
237
238 if (seq_no_segment_acked(conn, tqe->seg, conn->snd_una)) {
239 /* Remove acknowledged segment */
240 list_remove(cur);
241
242 if ((tqe->seg->ctrl & CTL_FIN) != 0) {
243 log_msg(LOG_DEFAULT, LVL_DEBUG, "Fin has been acked");
244 log_msg(LOG_DEFAULT, LVL_DEBUG, "SND.UNA=%" PRIu32
245 " SEG.SEQ=%" PRIu32 " SEG.LEN=%" PRIu32,
246 conn->snd_una, tqe->seg->seq, tqe->seg->len);
247 /* Our FIN has been acked */
248 conn->fin_is_acked = true;
249 }
250
251 tcp_segment_delete(tqe->seg);
252 free(tqe);
253
254 /* Reset retransmission timer */
255 tcp_tqueue_timer_set(conn);
256 }
257
258 cur = next;
259 }
260
261 /* Clear retransmission timer if the queue is empty. */
262 if (list_empty(&conn->retransmit.list))
263 tcp_tqueue_timer_clear(conn);
264
265 /* Possibly transmit more data */
266 tcp_tqueue_new_data(conn);
267}
268
269void tcp_conn_transmit_segment(tcp_conn_t *conn, tcp_segment_t *seg)
270{
271 log_msg(LOG_DEFAULT, LVL_DEBUG, "%s: tcp_conn_transmit_segment(%p, %p)",
272 conn->name, conn, seg);
273
274 seg->wnd = conn->rcv_wnd;
275
276 if ((seg->ctrl & CTL_ACK) != 0)
277 seg->ack = conn->rcv_nxt;
278 else
279 seg->ack = 0;
280
281 tcp_transmit_segment(&conn->ident, seg);
282}
283
284void tcp_transmit_segment(inet_ep2_t *epp, tcp_segment_t *seg)
285{
286 log_msg(LOG_DEFAULT, LVL_DEBUG,
287 "tcp_transmit_segment(l:(%u),f:(%u), %p)",
288 epp->local.port, epp->remote.port, seg);
289
290 log_msg(LOG_DEFAULT, LVL_DEBUG, "SEG.SEQ=%" PRIu32 ", SEG.WND=%" PRIu32,
291 seg->seq, seg->wnd);
292
293 tcp_segment_dump(seg);
294/*
295 tcp_pdu_prepare(conn, seg, &data, &len);
296 tcp_pdu_transmit(data, len);
297*/
298// tcp_rqueue_bounce_seg(sp, seg);
299// tcp_ncsim_bounce_seg(sp, seg);
300
301 tcp_pdu_t *pdu;
302
303 if (tcp_pdu_encode(epp, seg, &pdu) != EOK) {
304 log_msg(LOG_DEFAULT, LVL_WARN, "Not enough memory. Segment dropped.");
305 return;
306 }
307
308 tcp_transmit_pdu(pdu);
309 tcp_pdu_delete(pdu);
310}
311
312static void retransmit_timeout_func(void *arg)
313{
314 tcp_conn_t *conn = (tcp_conn_t *) arg;
315 tcp_tqueue_entry_t *tqe;
316 tcp_segment_t *rt_seg;
317 link_t *link;
318
319 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: retransmit_timeout_func(%p)", conn->name, conn);
320
321 tcp_conn_lock(conn);
322
323 if (conn->cstate == st_closed) {
324 log_msg(LOG_DEFAULT, LVL_DEBUG, "Connection already closed.");
325 tcp_conn_unlock(conn);
326 tcp_conn_delref(conn);
327 return;
328 }
329
330 link = list_first(&conn->retransmit.list);
331 if (link == NULL) {
332 log_msg(LOG_DEFAULT, LVL_DEBUG, "Nothing to retransmit");
333 tcp_conn_unlock(conn);
334 tcp_conn_delref(conn);
335 return;
336 }
337
338 tqe = list_get_instance(link, tcp_tqueue_entry_t, link);
339
340 rt_seg = tcp_segment_dup(tqe->seg);
341 if (rt_seg == NULL) {
342 log_msg(LOG_DEFAULT, LVL_ERROR, "Memory allocation failed.");
343 tcp_conn_unlock(conn);
344 tcp_conn_delref(conn);
345 /* XXX Handle properly */
346 return;
347 }
348
349 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: retransmitting segment", conn->name);
350 tcp_conn_transmit_segment(tqe->conn, rt_seg);
351
352 /* Reset retransmission timer */
353 tcp_tqueue_timer_set(tqe->conn);
354
355 tcp_conn_unlock(conn);
356 tcp_conn_delref(conn);
357
358 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: retransmit_timeout_func(%p) end", conn->name, conn);
359}
360
361/** Set or re-set retransmission timer */
362static void tcp_tqueue_timer_set(tcp_conn_t *conn)
363{
364 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: tcp_tqueue_timer_set() begin", conn->name);
365
366 /* Clear first to make sure we update refcnt correctly */
367 tcp_tqueue_timer_clear(conn);
368
369 tcp_conn_addref(conn);
370 fibril_timer_set_locked(conn->retransmit.timer, RETRANSMIT_TIMEOUT,
371 retransmit_timeout_func, (void *) conn);
372
373 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: tcp_tqueue_timer_set() end", conn->name);
374}
375
376/** Clear retransmission timer */
377static void tcp_tqueue_timer_clear(tcp_conn_t *conn)
378{
379 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: tcp_tqueue_timer_clear() begin", conn->name);
380
381 if (fibril_timer_clear_locked(conn->retransmit.timer) == fts_active)
382 tcp_conn_delref(conn);
383
384 log_msg(LOG_DEFAULT, LVL_DEBUG, "### %s: tcp_tqueue_timer_clear() end", conn->name);
385}
386
387/**
388 * @}
389 */
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