00001 /* 00002 * Copyright (C) 2001-2005 by egnite Software GmbH. All rights reserved. 00003 * 00004 * Redistribution and use in source and binary forms, with or without 00005 * modification, are permitted provided that the following conditions 00006 * are met: 00007 * 00008 * 1. Redistributions of source code must retain the above copyright 00009 * notice, this list of conditions and the following disclaimer. 00010 * 2. Redistributions in binary form must reproduce the above copyright 00011 * notice, this list of conditions and the following disclaimer in the 00012 * documentation and/or other materials provided with the distribution. 00013 * 3. Neither the name of the copyright holders nor the names of 00014 * contributors may be used to endorse or promote products derived 00015 * from this software without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY EGNITE SOFTWARE GMBH AND CONTRIBUTORS 00018 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00019 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 00020 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EGNITE 00021 * SOFTWARE GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 00022 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 00023 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 00024 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 00025 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 00026 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 00027 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00028 * SUCH DAMAGE. 00029 * 00030 * For additional information see http://www.ethernut.de/ 00031 * 00032 * - 00033 * Portions Copyright (C) 2000 David J. Hudson <dave@humbug.demon.co.uk> 00034 * 00035 * This file is distributed in the hope that it will be useful, but WITHOUT 00036 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 00037 * FITNESS FOR A PARTICULAR PURPOSE. 00038 * 00039 * You can redistribute this file and/or modify it under the terms of the GNU 00040 * General Public License (GPL) as published by the Free Software Foundation; 00041 * either version 2 of the License, or (at your discretion) any later version. 00042 * See the accompanying file "copying-gpl.txt" for more details. 00043 * 00044 * As a special exception to the GPL, permission is granted for additional 00045 * uses of the text contained in this file. See the accompanying file 00046 * "copying-liquorice.txt" for details. 00047 * - 00048 * Portions Copyright (c) 1983, 1993 by 00049 * The Regents of the University of California. All rights reserved. 00050 * 00051 * Redistribution and use in source and binary forms, with or without 00052 * modification, are permitted provided that the following conditions 00053 * are met: 00054 * 1. Redistributions of source code must retain the above copyright 00055 * notice, this list of conditions and the following disclaimer. 00056 * 2. Redistributions in binary form must reproduce the above copyright 00057 * notice, this list of conditions and the following disclaimer in the 00058 * documentation and/or other materials provided with the distribution. 00059 * 3. Neither the name of the University nor the names of its contributors 00060 * may be used to endorse or promote products derived from this software 00061 * without specific prior written permission. 00062 * 00063 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 00064 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00065 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00066 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 00067 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00068 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00069 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00070 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00071 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00072 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00073 * SUCH DAMAGE. 00074 * - 00075 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 00076 * 00077 * Permission to use, copy, modify, and distribute this software for any 00078 * purpose with or without fee is hereby granted, provided that the above 00079 * copyright notice and this permission notice appear in all copies, and that 00080 * the name of Digital Equipment Corporation not be used in advertising or 00081 * publicity pertaining to distribution of the document or software without 00082 * specific, written prior permission. 00083 * 00084 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 00085 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 00086 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 00087 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 00088 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 00089 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 00090 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 00091 * SOFTWARE. 00092 */ 00093 00094 /* 00095 * $Log: tcpout.c,v $ 00096 * Revision 1.10 2008/08/11 07:00:32 haraldkipp 00097 * BSD types replaced by stdint types (feature request #1282721). 00098 * 00099 * Revision 1.9 2008/04/06 13:29:01 haraldkipp 00100 * In unreliable or high traffic networks connections may suddenly freeze. 00101 * The problem is, that during overflows (happening every 65s) the 00102 * retransmission timer may be loaded with 0, which in turn disables all 00103 * outstanding retransmission. Applied fix contributed by Henrik Maier. 00104 * 00105 * Revision 1.8 2006/10/08 16:48:22 haraldkipp 00106 * Documentation fixed 00107 * 00108 * Revision 1.7 2006/03/02 19:57:34 haraldkipp 00109 * ICCARM insists on a (void *) typecast for the second parameter of memcpy(). 00110 * 00111 * Revision 1.6 2006/01/23 17:33:47 haraldkipp 00112 * Avoid memory alignment errors. 00113 * 00114 * Revision 1.5 2005/04/30 16:42:42 chaac 00115 * Fixed bug in handling of NUTDEBUG. Added include for cfg/os.h. If NUTDEBUG 00116 * is defined in NutConf, it will make effect where it is used. 00117 * 00118 * Revision 1.4 2005/04/05 17:41:48 haraldkipp 00119 * Header is dangerous when you forget to remove all debug outputs. 00120 * 00121 * Revision 1.3 2004/07/30 19:54:46 drsung 00122 * Some code of TCP stack redesigned. Round trip time calculation is now 00123 * supported. Fixed several bugs in TCP state machine. Now TCP connections 00124 * should be more reliable under heavy traffic or poor physical connections. 00125 * 00126 * Revision 1.2 2004/04/15 11:05:35 haraldkipp 00127 * Set retransmission timer on first transmit queue entry 00128 * 00129 * Revision 1.1.1.1 2003/05/09 14:41:40 haraldkipp 00130 * Initial using 3.2.1 00131 * 00132 * Revision 1.15 2003/03/31 12:29:17 harald 00133 * Check NEBUF allocation 00134 * 00135 * Revision 1.14 2003/02/04 18:14:57 harald 00136 * Version 3 released 00137 * 00138 * Revision 1.13 2002/09/15 16:50:44 harald 00139 * *** empty log message *** 00140 * 00141 * Revision 1.12 2002/06/26 17:29:36 harald 00142 * First pre-release with 2.4 stack 00143 * 00144 */ 00145 00146 #include <cfg/os.h> 00147 #include <string.h> 00148 00149 #include <sys/heap.h> 00150 #include <sys/event.h> 00151 #include <sys/timer.h> 00152 00153 #include <netinet/in.h> 00154 #include <netinet/ip.h> 00155 #include <netinet/icmp.h> 00156 #include <netinet/ip_icmp.h> 00157 #include <netinet/ipcsum.h> 00158 #include <sys/socket.h> 00159 #include <netinet/tcp.h> 00160 #include <net/errno.h> 00161 #include <sys/thread.h> 00162 00163 #ifdef NUTDEBUG 00164 #include <net/netdebug.h> 00165 #endif 00166 00206 int NutTcpOutput(TCPSOCKET * sock, CONST uint8_t * data, uint16_t size) 00207 { 00208 NETBUF *nb; 00209 NETBUF *nb_clone = 0; 00210 TCPHDR *th; 00211 uint16_t csum; 00212 uint8_t hlen; 00213 00214 /* 00215 * Check if anything to send at all. 00216 */ 00217 if (size == 0 00218 && (sock->so_tx_flags & (SO_SYN | SO_FIN | SO_FORCE)) == 0) 00219 return 0; 00220 00221 /* 00222 * Build TCP header. Add room for MAXSEG option if this is a 00223 * SYN segment. 00224 */ 00225 hlen = sizeof(TCPHDR); 00226 if (sock->so_tx_flags & SO_SYN) 00227 hlen += 4; 00228 if ((nb = NutNetBufAlloc(0, NBAF_TRANSPORT, hlen)) == 0) { 00229 sock->so_last_error = ENOBUFS; 00230 return -1; 00231 } 00232 th = (TCPHDR *) nb->nb_tp.vp; 00233 th->th_sport = sock->so_local_port; 00234 th->th_dport = sock->so_remote_port; 00235 th->th_x2 = 0; 00236 th->th_off = hlen >> 2; 00237 00238 sock->so_tx_flags &= ~SO_FORCE; 00239 00240 /* 00241 * Process ACK flag. 00242 */ 00243 th->th_seq = htonl(sock->so_tx_nxt); 00244 if (sock->so_tx_flags & SO_ACK) { 00245 th->th_flags = TH_ACK; 00246 sock->so_tx_flags &= ~SO_ACK; 00247 th->th_ack = htonl(sock->so_rx_nxt); 00248 } else { 00249 th->th_flags = 0; 00250 th->th_ack = 0; 00251 } 00252 00253 /* 00254 * Any SYN is sent first. Add options too. We rely on the caller 00255 * not to send a SYN segment with data, because this may break 00256 * some old stacks. 00257 */ 00258 if (sock->so_tx_flags & SO_SYN) { 00259 uint8_t *cp; 00260 uint16_t n_mss = htons(sock->so_mss); 00261 00262 th->th_flags |= TH_SYN; 00263 sock->so_tx_flags &= ~SO_SYN; 00264 sock->so_tx_nxt++; 00265 00266 cp = (uint8_t *) (th + 1); 00267 *cp++ = TCPOPT_MAXSEG; 00268 *cp++ = TCPOLEN_MAXSEG; 00269 *cp++ = *(uint8_t *)&n_mss; 00270 *cp = *((uint8_t *)(&n_mss) + 1); 00271 } 00272 00273 /* 00274 * Next preference is sending data. Set PUSH flag. 00275 */ 00276 else if (size) { 00277 if ((nb = NutNetBufAlloc(nb, NBAF_APPLICATION, size)) == 0) { 00278 sock->so_last_error = ENOBUFS; 00279 return -1; 00280 } 00281 memcpy(nb->nb_ap.vp, (void *)data, size); 00282 sock->so_tx_nxt += size; 00283 th->th_flags |= TH_PUSH; 00284 } 00285 00286 /* 00287 * If all data sent, transmit any waiting FIN. 00288 */ 00289 else if (sock->so_tx_flags & SO_FIN) { 00290 th->th_flags |= TH_FIN; 00291 sock->so_tx_flags &= ~SO_FIN; 00292 sock->so_tx_nxt++; 00293 //@@@printf ("[%04X]TcpOutput: sending FIN\n", (u_short) sock); 00294 } 00295 00296 /* 00297 * We close our receiver window, if it is 00298 * below the maximum segment size. 00299 */ 00300 if (sock->so_rx_win < sock->so_mss) 00301 th->th_win = 0; 00302 else 00303 th->th_win = htons(sock->so_rx_win); 00304 th->th_sum = 0; 00305 th->th_urp = 0; 00306 00307 /* 00308 * Calculate TCP checksum. 00309 */ 00310 csum = 00311 NutIpPseudoChkSumPartial(sock->so_local_addr, sock->so_remote_addr, 00312 IPPROTO_TCP, 00313 htons(nb->nb_tp.sz + nb->nb_ap.sz)); 00314 csum = NutIpChkSumPartial(csum, th, nb->nb_tp.sz); 00315 th->th_sum = NutIpChkSum(csum, nb->nb_ap.vp, nb->nb_ap.sz); 00316 00317 #ifdef NUTDEBUG 00318 if (__tcp_trf) 00319 NutDumpTcpHeader(__tcp_trs, "OUT", sock, nb); 00320 #endif 00321 00322 /* 00323 * To avoid a race condition in tcp state machine, the segment is first 00324 * appended to the transmission que, and then sent to the network. 00325 */ 00326 00327 /* 00328 * Append the segment to our transmission queue. 00329 */ 00330 //@@@printf ("[%04X]TcpOutput: size: %u, flags: %u\n", (u_short) sock, size, th->th_flags); 00331 if (size || ((th->th_flags & (TH_FIN | TH_SYN)))) { 00332 //@@@printf ("[%04X]TcpOutput: appending nb to queue\n", (u_short) sock); 00333 NETBUF *nbp; 00334 00335 nb->nb_next = 0; 00336 if ((nbp = sock->so_tx_nbq) == 0) { 00337 sock->so_tx_nbq = nb; 00338 /* 00339 * First entry, so initialize our retransmission timer. 00340 * It is also set at various places in the state machine, 00341 * but here is the best central point to do it. We may 00342 * carefully check later, if we can remove some in the 00343 * state machine. 00344 */ 00345 sock->so_retran_time = (uint16_t) NutGetMillis() | 1; 00346 } 00347 else { 00348 while (nbp->nb_next) 00349 nbp = nbp->nb_next; 00350 nbp->nb_next = nb; 00351 } 00352 if (sock->so_rtt_seq == 0) 00353 sock->so_rtt_seq = ntohl (th->th_seq); 00354 nb_clone = NutNetBufClone (nb); 00355 } 00356 else 00357 nb_clone = nb; 00358 00359 /* 00360 * IP output might fail because of routing, ARP or network device 00361 * problems or because the system ran out of memory. 00362 */ 00363 if (NutIpOutput(IPPROTO_TCP, sock->so_remote_addr, nb_clone)) 00364 return -1; 00365 00366 NutNetBufFree (nb_clone); 00367 return 0; 00368 } 00369 00370 00388 int NutTcpReject(NETBUF * nb) 00389 { 00390 uint16_t csum; 00391 IPHDR *ih = (IPHDR *) nb->nb_nw.vp; 00392 TCPHDR *th = (TCPHDR *) nb->nb_tp.vp; 00393 00394 /* 00395 * Never send RST in response to RST. 00396 */ 00397 if (th->th_flags & TH_RST) { 00398 NutNetBufFree(nb); 00399 return 0; 00400 } 00401 00402 /* 00403 * Remove any application data and TCP header options. 00404 */ 00405 nb->nb_ap.sz = 0; 00406 nb->nb_tp.sz = sizeof(TCPHDR); 00407 00408 /* 00409 * Swap ports. 00410 */ 00411 csum = th->th_sport; 00412 th->th_sport = th->th_dport; 00413 th->th_dport = csum; 00414 00415 /* 00416 * If the incoming segment has an ACK field, the reset 00417 * takes its sequence number from the ACK field of the 00418 * segment, otherwise the reset has sequence number zero 00419 * and the ACK field is set to the sum of the sequence 00420 * number and segment length of the incoming segment. 00421 */ 00422 if (th->th_flags & TH_ACK) { 00423 th->th_flags = TH_RST; 00424 th->th_seq = th->th_ack; 00425 th->th_ack = 0; 00426 } else { 00427 if (th->th_flags & TH_SYN) 00428 th->th_ack = htonl(ntohl(th->th_seq) + 1); 00429 else 00430 th->th_ack = th->th_seq; 00431 th->th_seq = 0; 00432 th->th_flags = TH_RST | TH_ACK; 00433 } 00434 th->th_x2 = 0; 00435 th->th_off = sizeof(TCPHDR) / 4; 00436 th->th_win = 0; 00437 th->th_urp = 0; 00438 00439 /* 00440 * Calculate TCP checksum without application data. 00441 */ 00442 th->th_sum = 0; 00443 csum = 00444 NutIpPseudoChkSumPartial(ih->ip_dst, ih->ip_src, IPPROTO_TCP, 00445 htons(nb->nb_tp.sz)); 00446 th->th_sum = NutIpChkSum(csum, th, nb->nb_tp.sz); 00447 00448 /* 00449 * Sent segment back to the source. 00450 */ 00451 #ifdef NUTDEBUG 00452 if (__tcp_trf) 00453 NutDumpTcpHeader(__tcp_trs, "REJ", 0, nb); 00454 #endif 00455 if(NutIpOutput(IPPROTO_TCP, ih->ip_src, nb) == 0) 00456 NutNetBufFree(nb); 00457 return 0; 00458 }