1/* 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993 3 * The Regents of the University of California. 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 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)tcp_subr.c 8.1 (Berkeley) 6/10/93 30 * tcp_subr.c,v 1.5 1994/10/08 22:39:58 phk Exp 31 */ 32 33/* 34 * Changes and additions relating to SLiRP 35 * Copyright (c) 1995 Danny Gasparovski. 36 * 37 * Please read the file COPYRIGHT for the 38 * terms and conditions of the copyright. 39 */ 40 41#define WANT_SYS_IOCTL_H 42#include <slirp.h> 43#include "proxy_common.h" 44 45/* patchable/settable parameters for tcp */ 46/* Don't do rfc1323 performance enhancements */ 47#define TCP_DO_RFC1323 0 48 49/* 50 * Tcp initialization 51 */ 52void 53tcp_init(void) 54{ 55 tcp_iss = 1; /* wrong */ 56 tcb.so_next = tcb.so_prev = &tcb; 57} 58 59/* 60 * Create template to be used to send tcp packets on a connection. 61 * Call after host entry created, fills 62 * in a skeletal tcp/ip header, minimizing the amount of work 63 * necessary when the connection is used. 64 */ 65/* struct tcpiphdr * */ 66void 67tcp_template(struct tcpcb *tp) 68{ 69 struct socket *so = tp->t_socket; 70 register struct tcpiphdr *n = &tp->t_template; 71 72 n->ti_mbuf = NULL; 73 n->ti_x1 = 0; 74 n->ti_pr = IPPROTO_TCP; 75 n->ti_len = htons(sizeof (struct tcpiphdr) - sizeof (struct ip)); 76 n->ti_src = ip_seth(so->so_faddr_ip); 77 n->ti_dst = ip_seth(so->so_laddr_ip); 78 n->ti_sport = port_seth(so->so_faddr_port); 79 n->ti_dport = port_seth(so->so_laddr_port); 80 81 n->ti_seq = 0; 82 n->ti_ack = 0; 83 n->ti_x2 = 0; 84 n->ti_off = 5; 85 n->ti_flags = 0; 86 n->ti_win = 0; 87 n->ti_sum = 0; 88 n->ti_urp = 0; 89} 90 91/* 92 * Send a single message to the TCP at address specified by 93 * the given TCP/IP header. If m == 0, then we make a copy 94 * of the tcpiphdr at ti and send directly to the addressed host. 95 * This is used to force keep alive messages out using the TCP 96 * template for a connection tp->t_template. If flags are given 97 * then we send a message back to the TCP which originated the 98 * segment ti, and discard the mbuf containing it and any other 99 * attached mbufs. 100 * 101 * In any case the ack and sequence number of the transmitted 102 * segment are as specified by the parameters. 103 */ 104void 105tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m, 106 tcp_seq ack, tcp_seq seq, int flags) 107{ 108 register int tlen; 109 int win = 0; 110 111 DEBUG_CALL("tcp_respond"); 112 DEBUG_ARG("tp = %lx", (long)tp); 113 DEBUG_ARG("ti = %lx", (long)ti); 114 DEBUG_ARG("m = %lx", (long)m); 115 DEBUG_ARG("ack = %u", ack); 116 DEBUG_ARG("seq = %u", seq); 117 DEBUG_ARG("flags = %x", flags); 118 119 if (tp) 120 win = sbspace(&tp->t_socket->so_rcv); 121 if (m == NULL) { 122 if ((m = m_get()) == NULL) 123 return; 124#ifdef TCP_COMPAT_42 125 tlen = 1; 126#else 127 tlen = 0; 128#endif 129 m->m_data += IF_MAXLINKHDR; 130 *mtod(m, struct tcpiphdr *) = *ti; 131 ti = mtod(m, struct tcpiphdr *); 132 flags = TH_ACK; 133 } else { 134 /* 135 * ti points into m so the next line is just making 136 * the mbuf point to ti 137 */ 138 m->m_data = (caddr_t)ti; 139 140 m->m_len = sizeof (struct tcpiphdr); 141 tlen = 0; 142#define xchg(a,b,type) { type t; t=a; a=b; b=t; } 143 xchg(ti->ti_dst, ti->ti_src, ipaddr_t); 144 xchg(ti->ti_dport, ti->ti_sport, port_t); 145#undef xchg 146 } 147 ti->ti_len = htons((u_short)(sizeof (struct tcphdr) + tlen)); 148 tlen += sizeof (struct tcpiphdr); 149 m->m_len = tlen; 150 151 ti->ti_mbuf = NULL; 152 ti->ti_x1 = 0; 153 ti->ti_seq = htonl(seq); 154 ti->ti_ack = htonl(ack); 155 ti->ti_x2 = 0; 156 ti->ti_off = sizeof (struct tcphdr) >> 2; 157 ti->ti_flags = flags; 158 if (tp) 159 ti->ti_win = htons((u_int16_t) (win >> tp->rcv_scale)); 160 else 161 ti->ti_win = htons((u_int16_t)win); 162 ti->ti_urp = 0; 163 ti->ti_sum = 0; 164 ti->ti_sum = cksum(m, tlen); 165 ((struct ip *)ti)->ip_len = tlen; 166 167 if(flags & TH_RST) 168 ((struct ip *)ti)->ip_ttl = MAXTTL; 169 else 170 ((struct ip *)ti)->ip_ttl = IPDEFTTL; 171 172 (void) ip_output((struct socket *)0, m); 173} 174 175/* 176 * Create a new TCP control block, making an 177 * empty reassembly queue and hooking it to the argument 178 * protocol control block. 179 */ 180struct tcpcb * 181tcp_newtcpcb(struct socket *so) 182{ 183 register struct tcpcb *tp; 184 185 tp = (struct tcpcb *)malloc(sizeof(*tp)); 186 if (tp == NULL) 187 return ((struct tcpcb *)0); 188 189 memset((char *) tp, 0, sizeof(struct tcpcb)); 190 tp->seg_next = tp->seg_prev = (struct tcpiphdr*)tp; 191 tp->t_maxseg = TCP_MSS; 192 193 tp->t_flags = TCP_DO_RFC1323 ? (TF_REQ_SCALE|TF_REQ_TSTMP) : 0; 194 tp->t_socket = so; 195 196 /* 197 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no 198 * rtt estimate. Set rttvar so that srtt + 2 * rttvar gives 199 * reasonable initial retransmit time. 200 */ 201 tp->t_srtt = TCPTV_SRTTBASE; 202 tp->t_rttvar = TCPTV_SRTTDFLT << 2; 203 tp->t_rttmin = TCPTV_MIN; 204 205 TCPT_RANGESET(tp->t_rxtcur, 206 ((TCPTV_SRTTBASE >> 2) + (TCPTV_SRTTDFLT << 2)) >> 1, 207 TCPTV_MIN, TCPTV_REXMTMAX); 208 209 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; 210 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; 211 tp->t_state = TCPS_CLOSED; 212 213 so->so_tcpcb = tp; 214 215 return (tp); 216} 217 218/* 219 * Drop a TCP connection, reporting 220 * the specified error. If connection is synchronized, 221 * then send a RST to peer. 222 */ 223struct tcpcb *tcp_drop(struct tcpcb *tp, int err) 224{ 225/* tcp_drop(tp, errno) 226 register struct tcpcb *tp; 227 int errno; 228{ 229*/ 230 231 DEBUG_CALL("tcp_drop"); 232 DEBUG_ARG("tp = %lx", (long)tp); 233 DEBUG_ARG("errno = %d", errno); 234 235 if (TCPS_HAVERCVDSYN(tp->t_state)) { 236 tp->t_state = TCPS_CLOSED; 237 (void) tcp_output(tp); 238 STAT(tcpstat.tcps_drops++); 239 } else 240 STAT(tcpstat.tcps_conndrops++); 241/* if (errno == ETIMEDOUT && tp->t_softerror) 242 * errno = tp->t_softerror; 243 */ 244/* so->so_error = errno; */ 245 return (tcp_close(tp)); 246} 247 248/* 249 * Close a TCP control block: 250 * discard all space held by the tcp 251 * discard internet protocol block 252 * wake up any sleepers 253 */ 254struct tcpcb * 255tcp_close(struct tcpcb *tp) 256{ 257 register struct tcpiphdr *t; 258 struct socket *so = tp->t_socket; 259 register struct mbuf *m; 260 261 DEBUG_CALL("tcp_close"); 262 DEBUG_ARG("tp = %lx", (long )tp); 263 264 /* free the reassembly queue, if any */ 265 t = tcpfrag_list_first(tp); 266 while (!tcpfrag_list_end(t, tp)) { 267 t = tcpiphdr_next(t); 268 m = tcpiphdr_prev(t)->ti_mbuf; 269 remque(tcpiphdr2qlink(tcpiphdr_prev(t))); 270 m_freem(m); 271 } 272 /* It's static */ 273/* if (tp->t_template) 274 * (void) m_free(dtom(tp->t_template)); 275 */ 276/* free(tp, M_PCB); */ 277 free(tp); 278 so->so_tcpcb = NULL; 279 soisfdisconnected(so); 280 /* clobber input socket cache if we're closing the cached connection */ 281 if (so == tcp_last_so) 282 tcp_last_so = &tcb; 283 socket_close(so->s); 284 sbfree(&so->so_rcv); 285 sbfree(&so->so_snd); 286 sofree(so); 287 STAT(tcpstat.tcps_closed++); 288 return ((struct tcpcb *)0); 289} 290 291#ifdef notdef 292void 293tcp_drain() 294{ 295 /* XXX */ 296} 297 298/* 299 * When a source quench is received, close congestion window 300 * to one segment. We will gradually open it again as we proceed. 301 */ 302void 303tcp_quench(i, errno) 304 305 int errno; 306{ 307 struct tcpcb *tp = intotcpcb(inp); 308 309 if (tp) 310 tp->snd_cwnd = tp->t_maxseg; 311} 312 313#endif /* notdef */ 314 315/* 316 * TCP protocol interface to socket abstraction. 317 */ 318 319/* 320 * User issued close, and wish to trail through shutdown states: 321 * if never received SYN, just forget it. If got a SYN from peer, 322 * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN. 323 * If already got a FIN from peer, then almost done; go to LAST_ACK 324 * state. In all other cases, have already sent FIN to peer (e.g. 325 * after PRU_SHUTDOWN), and just have to play tedious game waiting 326 * for peer to send FIN or not respond to keep-alives, etc. 327 * We can let the user exit from the close as soon as the FIN is acked. 328 */ 329void 330tcp_sockclosed(struct tcpcb *tp) 331{ 332 333 DEBUG_CALL("tcp_sockclosed"); 334 DEBUG_ARG("tp = %lx", (long)tp); 335 336 switch (tp->t_state) { 337 338 case TCPS_CLOSED: 339 case TCPS_LISTEN: 340 case TCPS_SYN_SENT: 341 tp->t_state = TCPS_CLOSED; 342 tp = tcp_close(tp); 343 break; 344 345 case TCPS_SYN_RECEIVED: 346 case TCPS_ESTABLISHED: 347 tp->t_state = TCPS_FIN_WAIT_1; 348 break; 349 350 case TCPS_CLOSE_WAIT: 351 tp->t_state = TCPS_LAST_ACK; 352 break; 353 } 354/* soisfdisconnecting(tp->t_socket); */ 355 if (tp && tp->t_state >= TCPS_FIN_WAIT_2) 356 soisfdisconnected(tp->t_socket); 357 if (tp) 358 tcp_output(tp); 359} 360 361static void 362tcp_proxy_event( struct socket* so, 363 int s, 364 ProxyEvent event ) 365{ 366 so->so_state &= ~SS_PROXIFIED; 367 368 if (event == PROXY_EVENT_CONNECTED) { 369 so->s = s; 370 so->so_state &= ~(SS_ISFCONNECTING); 371 } 372 else { 373 so->so_state = SS_NOFDREF; 374 } 375 376 /* continue the connect */ 377 tcp_input(NULL, sizeof(struct ip), so); 378} 379 380/* 381 * Connect to a host on the Internet 382 * Called by tcp_input 383 * Only do a connect, the tcp fields will be set in tcp_input 384 * return 0 if there's a result of the connect, 385 * else return -1 means we're still connecting 386 * The return value is almost always -1 since the socket is 387 * nonblocking. Connect returns after the SYN is sent, and does 388 * not wait for ACK+SYN. 389 */ 390int tcp_fconnect(struct socket *so) 391{ 392 int ret=0; 393 int try_proxy = 1; 394 SockAddress sockaddr; 395 uint32_t sock_ip; 396 uint16_t sock_port; 397 398 DEBUG_CALL("tcp_fconnect"); 399 DEBUG_ARG("so = %lx", (long )so); 400 401 sock_ip = so->so_faddr_ip; 402 sock_port = so->so_faddr_port; 403 404 if ((sock_ip & 0xffffff00) == special_addr_ip) { 405 /* It's an alias */ 406 int last_byte = sock_ip & 0xff; 407 408 if (CTL_IS_DNS(last_byte)) 409 sock_ip = dns_addr[last_byte - CTL_DNS]; 410 else 411 sock_ip = loopback_addr_ip; 412 try_proxy = 0; 413 } 414 415 sock_address_init_inet( &sockaddr, sock_ip, sock_port ); 416 417 DEBUG_MISC((dfd, " connect()ing, addr=%s, proxy=%d\n", 418 sock_address_to_string(&sockaddr), try_proxy)); 419 420 if (try_proxy) { 421 if (!proxy_manager_add(&sockaddr, SOCKET_STREAM, (ProxyEventFunc) tcp_proxy_event, so)) { 422 soisfconnecting(so); 423 so->s = -1; 424 so->so_state |= SS_PROXIFIED; 425 return 0; 426 } 427 } 428 429 if ((ret=so->s=socket_create_inet(SOCKET_STREAM)) >= 0) 430 { 431 int s = so->s; 432 433 socket_set_nonblock(s); 434 socket_set_xreuseaddr(s); 435 socket_set_oobinline(s); 436 437 /* We don't care what port we get */ 438 socket_connect(s, &sockaddr); 439 440 /* 441 * If it's not in progress, it failed, so we just return 0, 442 * without clearing SS_NOFDREF 443 */ 444 soisfconnecting(so); 445 } 446 447 return(ret); 448} 449 450/* 451 * Accept the socket and connect to the local-host 452 * 453 * We have a problem. The correct thing to do would be 454 * to first connect to the local-host, and only if the 455 * connection is accepted, then do an accept() here. 456 * But, a) we need to know who's trying to connect 457 * to the socket to be able to SYN the local-host, and 458 * b) we are already connected to the foreign host by 459 * the time it gets to accept(), so... We simply accept 460 * here and SYN the local-host. 461 */ 462void 463tcp_connect(struct socket *inso) 464{ 465 struct socket *so; 466 SockAddress addr; 467 uint32_t addr_ip; 468 struct tcpcb *tp; 469 int s; 470 471 DEBUG_CALL("tcp_connect"); 472 DEBUG_ARG("inso = %lx", (long)inso); 473 474 /* 475 * If it's an SS_ACCEPTONCE socket, no need to socreate() 476 * another socket, just use the accept() socket. 477 */ 478 if (inso->so_state & SS_FACCEPTONCE) { 479 /* FACCEPTONCE already have a tcpcb */ 480 so = inso; 481 } else { 482 if ((so = socreate()) == NULL) { 483 /* If it failed, get rid of the pending connection */ 484 socket_close(socket_accept(inso->s, NULL)); 485 return; 486 } 487 if (tcp_attach(so) < 0) { 488 free(so); /* NOT sofree */ 489 return; 490 } 491 so->so_laddr_ip = inso->so_laddr_ip; 492 so->so_laddr_port = inso->so_laddr_port; 493 } 494 495 (void) tcp_mss(sototcpcb(so), 0); 496 497 if ((s = socket_accept(inso->s, &addr)) < 0) { 498 tcp_close(sototcpcb(so)); /* This will sofree() as well */ 499 return; 500 } 501 socket_set_nonblock(s); 502 socket_set_xreuseaddr(s); 503 socket_set_oobinline(s); 504 socket_set_nodelay(s); 505 506 so->so_faddr_port = sock_address_get_port(&addr); 507 508 addr_ip = sock_address_get_ip(&addr); 509 510 so->so_faddr_ip = addr_ip; 511 /* Translate connections from localhost to the real hostname */ 512 if (addr_ip == 0 || addr_ip == loopback_addr_ip) 513 so->so_faddr_ip = alias_addr_ip; 514 515 /* Close the accept() socket, set right state */ 516 if (inso->so_state & SS_FACCEPTONCE) { 517 socket_close(so->s); /* If we only accept once, close the accept() socket */ 518 so->so_state = SS_NOFDREF; /* Don't select it yet, even though we have an FD */ 519 /* if it's not FACCEPTONCE, it's already NOFDREF */ 520 } 521 so->s = s; 522 523 so->so_iptos = tcp_tos(so); 524 tp = sototcpcb(so); 525 526 tcp_template(tp); 527 528 /* Compute window scaling to request. */ 529/* while (tp->request_r_scale < TCP_MAX_WINSHIFT && 530 * (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat) 531 * tp->request_r_scale++; 532 */ 533 534/* soisconnecting(so); */ /* NOFDREF used instead */ 535 STAT(tcpstat.tcps_connattempt++); 536 537 tp->t_state = TCPS_SYN_SENT; 538 tp->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT; 539 tp->iss = tcp_iss; 540 tcp_iss += TCP_ISSINCR/2; 541 tcp_sendseqinit(tp); 542 tcp_output(tp); 543} 544 545/* 546 * Attach a TCPCB to a socket. 547 */ 548int 549tcp_attach(struct socket *so) 550{ 551 if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) 552 return -1; 553 554 insque(so, &tcb); 555 556 return 0; 557} 558 559/* 560 * Set the socket's type of service field 561 */ 562static const struct tos_t tcptos[] = { 563 {0, 20, IPTOS_THROUGHPUT, 0}, /* ftp data */ 564 {21, 21, IPTOS_LOWDELAY, EMU_FTP}, /* ftp control */ 565 {0, 23, IPTOS_LOWDELAY, 0}, /* telnet */ 566 {0, 80, IPTOS_THROUGHPUT, 0}, /* WWW */ 567 {0, 513, IPTOS_LOWDELAY, EMU_RLOGIN|EMU_NOCONNECT}, /* rlogin */ 568 {0, 514, IPTOS_LOWDELAY, EMU_RSH|EMU_NOCONNECT}, /* shell */ 569 {0, 544, IPTOS_LOWDELAY, EMU_KSH}, /* kshell */ 570 {0, 543, IPTOS_LOWDELAY, 0}, /* klogin */ 571 {0, 6667, IPTOS_THROUGHPUT, EMU_IRC}, /* IRC */ 572 {0, 6668, IPTOS_THROUGHPUT, EMU_IRC}, /* IRC undernet */ 573 {0, 7070, IPTOS_LOWDELAY, EMU_REALAUDIO }, /* RealAudio control */ 574 {0, 113, IPTOS_LOWDELAY, EMU_IDENT }, /* identd protocol */ 575 {0, 0, 0, 0} 576}; 577 578#ifdef CONFIG_QEMU 579static 580#endif 581struct emu_t *tcpemu = NULL; 582 583/* 584 * Return TOS according to the above table 585 */ 586u_int8_t 587tcp_tos(struct socket *so) 588{ 589 int i = 0; 590 struct emu_t *emup; 591 592 while(tcptos[i].tos) { 593 if ((tcptos[i].fport && so->so_faddr_port == tcptos[i].fport) || 594 (tcptos[i].lport && so->so_laddr_port == tcptos[i].lport)) { 595 so->so_emu = tcptos[i].emu; 596 return tcptos[i].tos; 597 } 598 i++; 599 } 600 601 /* Nope, lets see if there's a user-added one */ 602 for (emup = tcpemu; emup; emup = emup->next) { 603 if ((emup->fport && (so->so_faddr_port == emup->fport)) || 604 (emup->lport && (so->so_laddr_port == emup->lport))) { 605 so->so_emu = emup->emu; 606 return emup->tos; 607 } 608 } 609 return 0; 610} 611 612#if 0 613int do_echo = -1; 614#endif 615 616/* 617 * Emulate programs that try and connect to us 618 * This includes ftp (the data connection is 619 * initiated by the server) and IRC (DCC CHAT and 620 * DCC SEND) for now 621 * 622 * NOTE: It's possible to crash SLiRP by sending it 623 * unstandard strings to emulate... if this is a problem, 624 * more checks are needed here 625 * 626 * XXX Assumes the whole command came in one packet 627 * 628 * XXX Some ftp clients will have their TOS set to 629 * LOWDELAY and so Nagel will kick in. Because of this, 630 * we'll get the first letter, followed by the rest, so 631 * we simply scan for ORT instead of PORT... 632 * DCC doesn't have this problem because there's other stuff 633 * in the packet before the DCC command. 634 * 635 * Return 1 if the mbuf m is still valid and should be 636 * sbappend()ed 637 * 638 * NOTE: if you return 0 you MUST m_free() the mbuf! 639 */ 640int 641tcp_emu(struct socket *so, struct mbuf *m) 642{ 643 u_int n1, n2, n3, n4, n5, n6; 644 char buff[257]; 645 u_int32_t laddr; 646 u_int lport; 647 char *bptr; 648 649 DEBUG_CALL("tcp_emu"); 650 DEBUG_ARG("so = %lx", (long)so); 651 DEBUG_ARG("m = %lx", (long)m); 652 653 switch(so->so_emu) { 654 int x, i; 655 656 case EMU_IDENT: 657 /* 658 * Identification protocol as per rfc-1413 659 */ 660 661 { 662 struct socket *tmpso; 663 SockAddress addr; 664 struct sbuf *so_rcv = &so->so_rcv; 665 666 memcpy(so_rcv->sb_wptr, m->m_data, m->m_len); 667 so_rcv->sb_wptr += m->m_len; 668 so_rcv->sb_rptr += m->m_len; 669 m->m_data[m->m_len] = 0; /* NULL terminate */ 670 if (strchr(m->m_data, '\r') || strchr(m->m_data, '\n')) { 671 if (sscanf(so_rcv->sb_data, "%u%*[ ,]%u", &n1, &n2) == 2) { 672 /* n2 is the one on our host */ 673 for (tmpso = tcb.so_next; tmpso != &tcb; tmpso = tmpso->so_next) { 674 if (tmpso->so_laddr_ip == so->so_laddr_ip && 675 tmpso->so_laddr_port == n2 && 676 tmpso->so_faddr_ip == so->so_faddr_ip && 677 tmpso->so_faddr_port == n1) { 678 if (socket_get_address(tmpso->s, &addr) == 0) 679 n2 = sock_address_get_port(&addr); 680 break; 681 } 682 } 683 } 684 so_rcv->sb_cc = snprintf(so_rcv->sb_data, 685 so_rcv->sb_datalen, 686 "%d,%d\r\n", n1, n2); 687 so_rcv->sb_rptr = so_rcv->sb_data; 688 so_rcv->sb_wptr = so_rcv->sb_data + so_rcv->sb_cc; 689 } 690 m_free(m); 691 return 0; 692 } 693 694 case EMU_FTP: /* ftp */ 695 *(m->m_data+m->m_len) = 0; /* NUL terminate for strstr */ 696 if ((bptr = (char *)strstr(m->m_data, "ORT")) != NULL) { 697 /* 698 * Need to emulate the PORT command 699 */ 700 x = sscanf(bptr, "ORT %u,%u,%u,%u,%u,%u\r\n%256[^\177]", 701 &n1, &n2, &n3, &n4, &n5, &n6, buff); 702 if (x < 6) 703 return 1; 704 705 laddr = (n1 << 24) | (n2 << 16) | (n3 << 8) | (n4); 706 lport = (n5 << 8) | (n6); 707 708 if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL) 709 return 1; 710 711 n6 = so->so_faddr_port; 712 713 n5 = (n6 >> 8) & 0xff; 714 n6 &= 0xff; 715 716 laddr = so->so_faddr_ip; 717 718 n1 = ((laddr >> 24) & 0xff); 719 n2 = ((laddr >> 16) & 0xff); 720 n3 = ((laddr >> 8) & 0xff); 721 n4 = (laddr & 0xff); 722 723 m->m_len = bptr - m->m_data; /* Adjust length */ 724 m->m_len += snprintf(bptr, m->m_hdr.mh_size - m->m_len, 725 "ORT %d,%d,%d,%d,%d,%d\r\n%s", 726 n1, n2, n3, n4, n5, n6, x==7?buff:""); 727 return 1; 728 } else if ((bptr = (char *)strstr(m->m_data, "27 Entering")) != NULL) { 729 /* 730 * Need to emulate the PASV response 731 */ 732 x = sscanf(bptr, "27 Entering Passive Mode (%u,%u,%u,%u,%u,%u)\r\n%256[^\177]", 733 &n1, &n2, &n3, &n4, &n5, &n6, buff); 734 if (x < 6) 735 return 1; 736 737 laddr = (n1 << 24) | (n2 << 16) | (n3 << 8) | (n4); 738 lport = (n5 << 8) | (n6); 739 740 if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL) 741 return 1; 742 743 n6 = so->so_faddr_port; 744 745 n5 = (n6 >> 8) & 0xff; 746 n6 &= 0xff; 747 748 laddr = so->so_faddr_ip; 749 750 n1 = ((laddr >> 24) & 0xff); 751 n2 = ((laddr >> 16) & 0xff); 752 n3 = ((laddr >> 8) & 0xff); 753 n4 = (laddr & 0xff); 754 755 m->m_len = bptr - m->m_data; /* Adjust length */ 756 m->m_len += snprintf(bptr, m->m_hdr.mh_size - m->m_len, 757 "27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%s", 758 n1, n2, n3, n4, n5, n6, x==7?buff:""); 759 760 return 1; 761 } 762 763 return 1; 764 765 case EMU_KSH: 766 /* 767 * The kshell (Kerberos rsh) and shell services both pass 768 * a local port port number to carry signals to the server 769 * and stderr to the client. It is passed at the beginning 770 * of the connection as a NUL-terminated decimal ASCII string. 771 */ 772 so->so_emu = 0; 773 for (lport = 0, i = 0; i < m->m_len-1; ++i) { 774 if (m->m_data[i] < '0' || m->m_data[i] > '9') 775 return 1; /* invalid number */ 776 lport *= 10; 777 lport += m->m_data[i] - '0'; 778 } 779 if (m->m_data[m->m_len-1] == '\0' && lport != 0 && 780 (so = solisten(0, so->so_laddr_ip, lport, SS_FACCEPTONCE)) != NULL) 781 m->m_len = snprintf(m->m_data, m->m_hdr.mh_size, "%d", 782 so->so_faddr_port) + 1; 783 return 1; 784 785 case EMU_IRC: 786 /* 787 * Need to emulate DCC CHAT, DCC SEND and DCC MOVE 788 */ 789 *(m->m_data+m->m_len) = 0; /* NULL terminate the string for strstr */ 790 if ((bptr = (char *)strstr(m->m_data, "DCC")) == NULL) 791 return 1; 792 793 /* The %256s is for the broken mIRC */ 794 if (sscanf(bptr, "DCC CHAT %256s %u %u", buff, &laddr, &lport) == 3) { 795 if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL) 796 return 1; 797 798 m->m_len = bptr - m->m_data; /* Adjust length */ 799 m->m_len += snprintf(bptr, m->m_hdr.mh_size, 800 "DCC CHAT chat %lu %u%c\n", 801 (unsigned long) so->so_faddr_ip, 802 so->so_faddr_port, 1); 803 } else if (sscanf(bptr, "DCC SEND %256s %u %u %u", buff, &laddr, &lport, &n1) == 4) { 804 if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL) 805 return 1; 806 807 m->m_len = bptr - m->m_data; /* Adjust length */ 808 m->m_len += snprintf(bptr, m->m_hdr.mh_size, 809 "DCC SEND %s %u %u %u%c\n", buff, 810 so->so_faddr_ip, so->so_faddr_port, n1, 1); 811 } else if (sscanf(bptr, "DCC MOVE %256s %u %u %u", buff, &laddr, &lport, &n1) == 4) { 812 if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL) 813 return 1; 814 815 m->m_len = bptr - m->m_data; /* Adjust length */ 816 m->m_len += snprintf(bptr, m->m_hdr.mh_size, 817 "DCC MOVE %s %lu %u %u%c\n", buff, 818 (unsigned long)so->so_faddr_ip, 819 so->so_faddr_port, n1, 1); 820 } 821 return 1; 822 823 case EMU_REALAUDIO: 824 /* 825 * RealAudio emulation - JP. We must try to parse the incoming 826 * data and try to find the two characters that contain the 827 * port number. Then we redirect an udp port and replace the 828 * number with the real port we got. 829 * 830 * The 1.0 beta versions of the player are not supported 831 * any more. 832 * 833 * A typical packet for player version 1.0 (release version): 834 * 835 * 0000:50 4E 41 00 05 836 * 0000:00 01 00 02 1B D7 00 00 67 E6 6C DC 63 00 12 50 .....×..gælÜc..P 837 * 0010:4E 43 4C 49 45 4E 54 20 31 30 31 20 41 4C 50 48 NCLIENT 101 ALPH 838 * 0020:41 6C 00 00 52 00 17 72 61 66 69 6C 65 73 2F 76 Al..R..rafiles/v 839 * 0030:6F 61 2F 65 6E 67 6C 69 73 68 5F 2E 72 61 79 42 oa/english_.rayB 840 * 841 * Now the port number 0x1BD7 is found at offset 0x04 of the 842 * Now the port number 0x1BD7 is found at offset 0x04 of the 843 * second packet. This time we received five bytes first and 844 * then the rest. You never know how many bytes you get. 845 * 846 * A typical packet for player version 2.0 (beta): 847 * 848 * 0000:50 4E 41 00 06 00 02 00 00 00 01 00 02 1B C1 00 PNA...........Á. 849 * 0010:00 67 75 78 F5 63 00 0A 57 69 6E 32 2E 30 2E 30 .guxõc..Win2.0.0 850 * 0020:2E 35 6C 00 00 52 00 1C 72 61 66 69 6C 65 73 2F .5l..R..rafiles/ 851 * 0030:77 65 62 73 69 74 65 2F 32 30 72 65 6C 65 61 73 website/20releas 852 * 0040:65 2E 72 61 79 53 00 00 06 36 42 e.rayS...6B 853 * 854 * Port number 0x1BC1 is found at offset 0x0d. 855 * 856 * This is just a horrible switch statement. Variable ra tells 857 * us where we're going. 858 */ 859 860 bptr = m->m_data; 861 while (bptr < m->m_data + m->m_len) { 862 u_short p; 863 static int ra = 0; 864 char ra_tbl[4]; 865 866 ra_tbl[0] = 0x50; 867 ra_tbl[1] = 0x4e; 868 ra_tbl[2] = 0x41; 869 ra_tbl[3] = 0; 870 871 switch (ra) { 872 case 0: 873 case 2: 874 case 3: 875 if (*bptr++ != ra_tbl[ra]) { 876 ra = 0; 877 continue; 878 } 879 break; 880 881 case 1: 882 /* 883 * We may get 0x50 several times, ignore them 884 */ 885 if (*bptr == 0x50) { 886 ra = 1; 887 bptr++; 888 continue; 889 } else if (*bptr++ != ra_tbl[ra]) { 890 ra = 0; 891 continue; 892 } 893 break; 894 895 case 4: 896 /* 897 * skip version number 898 */ 899 bptr++; 900 break; 901 902 case 5: 903 /* 904 * The difference between versions 1.0 and 905 * 2.0 is here. For future versions of 906 * the player this may need to be modified. 907 */ 908 if (*(bptr + 1) == 0x02) 909 bptr += 8; 910 else 911 bptr += 4; 912 break; 913 914 case 6: 915 /* This is the field containing the port 916 * number that RA-player is listening to. 917 */ 918 lport = (((u_char*)bptr)[0] << 8) 919 + ((u_char *)bptr)[1]; 920 if (lport < 6970) 921 lport += 256; /* don't know why */ 922 if (lport < 6970 || lport > 7170) 923 return 1; /* failed */ 924 925 /* try to get udp port between 6970 - 7170 */ 926 for (p = 6970; p < 7071; p++) { 927 if (udp_listen( p, 928 so->so_laddr_ip, 929 lport, 930 SS_FACCEPTONCE)) { 931 break; 932 } 933 } 934 if (p == 7071) 935 p = 0; 936 *(u_char *)bptr++ = (p >> 8) & 0xff; 937 *(u_char *)bptr++ = p & 0xff; 938 ra = 0; 939 return 1; /* port redirected, we're done */ 940 break; 941 942 default: 943 ra = 0; 944 } 945 ra++; 946 } 947 return 1; 948 949 default: 950 /* Ooops, not emulated, won't call tcp_emu again */ 951 so->so_emu = 0; 952 return 1; 953 } 954} 955 956/* 957 * Do misc. config of SLiRP while its running. 958 * Return 0 if this connections is to be closed, 1 otherwise, 959 * return 2 if this is a command-line connection 960 */ 961int 962tcp_ctl(struct socket *so) 963{ 964 struct sbuf *sb = &so->so_snd; 965 int command; 966 struct ex_list *ex_ptr; 967 int do_pty; 968 // struct socket *tmpso; 969 970 DEBUG_CALL("tcp_ctl"); 971 DEBUG_ARG("so = %lx", (long )so); 972 973#if 0 974 /* 975 * Check if they're authorised 976 */ 977 if (ctl_addr_ip && (ctl_addr_ip == -1 || (so->so_laddr_ip != ctl_addr_ip))) { 978 sb->sb_cc = sprintf(sb->sb_wptr,"Error: Permission denied.\r\n"); 979 sb->sb_wptr += sb->sb_cc; 980 return 0; 981 } 982#endif 983 command = (so->so_faddr_ip & 0xff); 984 985 switch(command) { 986 default: /* Check for exec's */ 987 988 /* 989 * Check if it's pty_exec 990 */ 991 for (ex_ptr = exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) { 992 if (ex_ptr->ex_fport == so->so_faddr_port && 993 command == ex_ptr->ex_addr) { 994 if (ex_ptr->ex_pty == 3) { 995 so->s = -1; 996 so->extra = (void *)ex_ptr->ex_exec; 997 return 1; 998 } 999 do_pty = ex_ptr->ex_pty; 1000 goto do_exec; 1001 } 1002 } 1003 1004 /* 1005 * Nothing bound.. 1006 */ 1007 /* tcp_fconnect(so); */ 1008 1009 /* FALLTHROUGH */ 1010 case CTL_ALIAS: 1011 sb->sb_cc = snprintf(sb->sb_wptr, sb->sb_datalen - (sb->sb_wptr - sb->sb_data), 1012 "Error: No application configured.\r\n"); 1013 sb->sb_wptr += sb->sb_cc; 1014 return(0); 1015 1016 do_exec: 1017 DEBUG_MISC((dfd, " executing %s \n",ex_ptr->ex_exec)); 1018 return(fork_exec(so, ex_ptr->ex_exec, do_pty)); 1019 1020#if 0 1021 case CTL_CMD: 1022 for (tmpso = tcb.so_next; tmpso != &tcb; tmpso = tmpso->so_next) { 1023 if (tmpso->so_emu == EMU_CTL && 1024 !(tmpso->so_tcpcb? 1025 (tmpso->so_tcpcb->t_state & (TCPS_TIME_WAIT|TCPS_LAST_ACK)) 1026 :0)) { 1027 /* Ooops, control connection already active */ 1028 sb->sb_cc = sprintf(sb->sb_wptr,"Sorry, already connected.\r\n"); 1029 sb->sb_wptr += sb->sb_cc; 1030 return 0; 1031 } 1032 } 1033 so->so_emu = EMU_CTL; 1034 ctl_password_ok = 0; 1035 sb->sb_cc = sprintf(sb->sb_wptr, "Slirp command-line ready (type \"help\" for help).\r\nSlirp> "); 1036 sb->sb_wptr += sb->sb_cc; 1037 do_echo=-1; 1038 return(2); 1039#endif 1040 } 1041} 1042