udp_usrreq.c revision 1.31
1 /* $NetBSD: udp_usrreq.c,v 1.31 1996/05/23 16:22:32 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)udp_usrreq.c 8.4 (Berkeley) 1/21/94 36 */ 37 38 #include <sys/param.h> 39 #include <sys/malloc.h> 40 #include <sys/mbuf.h> 41 #include <sys/protosw.h> 42 #include <sys/socket.h> 43 #include <sys/socketvar.h> 44 #include <sys/errno.h> 45 #include <sys/stat.h> 46 #include <sys/systm.h> 47 #include <sys/proc.h> 48 49 #include <vm/vm.h> 50 #include <sys/sysctl.h> 51 52 #include <net/if.h> 53 #include <net/route.h> 54 55 #include <netinet/in.h> 56 #include <netinet/in_systm.h> 57 #include <netinet/in_var.h> 58 #include <netinet/ip.h> 59 #include <netinet/in_pcb.h> 60 #include <netinet/ip_var.h> 61 #include <netinet/ip_icmp.h> 62 #include <netinet/udp.h> 63 #include <netinet/udp_var.h> 64 65 #include <machine/stdarg.h> 66 67 /* 68 * UDP protocol implementation. 69 * Per RFC 768, August, 1980. 70 */ 71 #ifndef COMPAT_42 72 int udpcksum = 1; 73 #else 74 int udpcksum = 0; /* XXX */ 75 #endif 76 77 struct sockaddr_in udp_in = { sizeof(udp_in), AF_INET }; 78 79 static void udp_notify __P((struct inpcb *, int)); 80 static struct mbuf *udp_saveopt __P((caddr_t, int, int)); 81 82 #ifndef UDBHASHSIZE 83 #define UDBHASHSIZE 128 84 #endif 85 int udbhashsize = UDBHASHSIZE; 86 87 void 88 udp_init() 89 { 90 91 in_pcbinit(&udbtable, udbhashsize); 92 } 93 94 void 95 #if __STDC__ 96 udp_input(struct mbuf *m, ...) 97 #else 98 udp_input(m, va_alist) 99 struct mbuf *m; 100 va_dcl 101 #endif 102 { 103 register struct ip *ip; 104 register struct udphdr *uh; 105 register struct inpcb *inp; 106 struct mbuf *opts = 0; 107 int len; 108 struct ip save_ip; 109 int iphlen; 110 va_list ap; 111 112 va_start(ap, m); 113 iphlen = va_arg(ap, int); 114 va_end(ap); 115 116 udpstat.udps_ipackets++; 117 118 /* 119 * Strip IP options, if any; should skip this, 120 * make available to user, and use on returned packets, 121 * but we don't yet have a way to check the checksum 122 * with options still present. 123 */ 124 if (iphlen > sizeof (struct ip)) { 125 ip_stripoptions(m, (struct mbuf *)0); 126 iphlen = sizeof(struct ip); 127 } 128 129 /* 130 * Get IP and UDP header together in first mbuf. 131 */ 132 ip = mtod(m, struct ip *); 133 if (m->m_len < iphlen + sizeof(struct udphdr)) { 134 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 135 udpstat.udps_hdrops++; 136 return; 137 } 138 ip = mtod(m, struct ip *); 139 } 140 uh = (struct udphdr *)((caddr_t)ip + iphlen); 141 142 /* 143 * Make mbuf data length reflect UDP length. 144 * If not enough data to reflect UDP length, drop. 145 */ 146 len = ntohs((u_int16_t)uh->uh_ulen); 147 if (ip->ip_len != len) { 148 if (len > ip->ip_len) { 149 udpstat.udps_badlen++; 150 goto bad; 151 } 152 m_adj(m, len - ip->ip_len); 153 /* ip->ip_len = len; */ 154 } 155 /* 156 * Save a copy of the IP header in case we want restore it 157 * for sending an ICMP error message in response. 158 */ 159 save_ip = *ip; 160 161 /* 162 * Checksum extended UDP header and data. 163 */ 164 if (uh->uh_sum) { 165 bzero(((struct ipovly *)ip)->ih_x1, 166 sizeof ((struct ipovly *)ip)->ih_x1); 167 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 168 if ((uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) != 0) { 169 udpstat.udps_badsum++; 170 m_freem(m); 171 return; 172 } 173 } 174 175 if (IN_MULTICAST(ip->ip_dst.s_addr) || 176 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 177 struct socket *last; 178 /* 179 * Deliver a multicast or broadcast datagram to *all* sockets 180 * for which the local and remote addresses and ports match 181 * those of the incoming datagram. This allows more than 182 * one process to receive multi/broadcasts on the same port. 183 * (This really ought to be done for unicast datagrams as 184 * well, but that would cause problems with existing 185 * applications that open both address-specific sockets and 186 * a wildcard socket listening to the same port -- they would 187 * end up receiving duplicates of every unicast datagram. 188 * Those applications open the multiple sockets to overcome an 189 * inadequacy of the UDP socket interface, but for backwards 190 * compatibility we avoid the problem here rather than 191 * fixing the interface. Maybe 4.5BSD will remedy this?) 192 */ 193 194 /* 195 * Construct sockaddr format source address. 196 */ 197 udp_in.sin_port = uh->uh_sport; 198 udp_in.sin_addr = ip->ip_src; 199 m->m_len -= sizeof (struct udpiphdr); 200 m->m_data += sizeof (struct udpiphdr); 201 /* 202 * Locate pcb(s) for datagram. 203 * (Algorithm copied from raw_intr().) 204 */ 205 last = NULL; 206 for (inp = udbtable.inpt_queue.cqh_first; 207 inp != (struct inpcb *)&udbtable.inpt_queue; 208 inp = inp->inp_queue.cqe_next) { 209 if (inp->inp_lport != uh->uh_dport) 210 continue; 211 if (inp->inp_laddr.s_addr != INADDR_ANY) { 212 if (inp->inp_laddr.s_addr != 213 ip->ip_dst.s_addr) 214 continue; 215 } 216 if (inp->inp_faddr.s_addr != INADDR_ANY) { 217 if (inp->inp_faddr.s_addr != 218 ip->ip_src.s_addr || 219 inp->inp_fport != uh->uh_sport) 220 continue; 221 } 222 223 if (last != NULL) { 224 struct mbuf *n; 225 226 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) { 227 if (sbappendaddr(&last->so_rcv, 228 sintosa(&udp_in), n, 229 (struct mbuf *)0) == 0) { 230 m_freem(n); 231 udpstat.udps_fullsock++; 232 } else 233 sorwakeup(last); 234 } 235 } 236 last = inp->inp_socket; 237 /* 238 * Don't look for additional matches if this one does 239 * not have either the SO_REUSEPORT or SO_REUSEADDR 240 * socket options set. This heuristic avoids searching 241 * through all pcbs in the common case of a non-shared 242 * port. It * assumes that an application will never 243 * clear these options after setting them. 244 */ 245 if ((last->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0) 246 break; 247 } 248 249 if (last == NULL) { 250 /* 251 * No matching pcb found; discard datagram. 252 * (No need to send an ICMP Port Unreachable 253 * for a broadcast or multicast datgram.) 254 */ 255 udpstat.udps_noportbcast++; 256 goto bad; 257 } 258 if (sbappendaddr(&last->so_rcv, sintosa(&udp_in), m, 259 (struct mbuf *)0) == 0) { 260 udpstat.udps_fullsock++; 261 goto bad; 262 } 263 sorwakeup(last); 264 return; 265 } 266 /* 267 * Locate pcb for datagram. 268 */ 269 inp = in_pcbhashlookup(&udbtable, ip->ip_src, uh->uh_sport, 270 ip->ip_dst, uh->uh_dport); 271 if (inp == 0) { 272 ++udpstat.udps_pcbhashmiss; 273 inp = in_pcblookup(&udbtable, ip->ip_src, uh->uh_sport, 274 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD); 275 if (inp == 0) { 276 udpstat.udps_noport++; 277 if (m->m_flags & (M_BCAST | M_MCAST)) { 278 udpstat.udps_noportbcast++; 279 goto bad; 280 } 281 *ip = save_ip; 282 ip->ip_len += iphlen; 283 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 284 return; 285 } 286 } 287 288 /* 289 * Construct sockaddr format source address. 290 * Stuff source address and datagram in user buffer. 291 */ 292 udp_in.sin_port = uh->uh_sport; 293 udp_in.sin_addr = ip->ip_src; 294 if (inp->inp_flags & INP_CONTROLOPTS) { 295 struct mbuf **mp = &opts; 296 297 if (inp->inp_flags & INP_RECVDSTADDR) { 298 *mp = udp_saveopt((caddr_t) &ip->ip_dst, 299 sizeof(struct in_addr), IP_RECVDSTADDR); 300 if (*mp) 301 mp = &(*mp)->m_next; 302 } 303 #ifdef notyet 304 /* options were tossed above */ 305 if (inp->inp_flags & INP_RECVOPTS) { 306 *mp = udp_saveopt((caddr_t) opts_deleted_above, 307 sizeof(struct in_addr), IP_RECVOPTS); 308 if (*mp) 309 mp = &(*mp)->m_next; 310 } 311 /* ip_srcroute doesn't do what we want here, need to fix */ 312 if (inp->inp_flags & INP_RECVRETOPTS) { 313 *mp = udp_saveopt((caddr_t) ip_srcroute(), 314 sizeof(struct in_addr), IP_RECVRETOPTS); 315 if (*mp) 316 mp = &(*mp)->m_next; 317 } 318 #endif 319 } 320 iphlen += sizeof(struct udphdr); 321 m->m_len -= iphlen; 322 m->m_pkthdr.len -= iphlen; 323 m->m_data += iphlen; 324 if (sbappendaddr(&inp->inp_socket->so_rcv, sintosa(&udp_in), m, 325 opts) == 0) { 326 udpstat.udps_fullsock++; 327 goto bad; 328 } 329 sorwakeup(inp->inp_socket); 330 return; 331 bad: 332 m_freem(m); 333 if (opts) 334 m_freem(opts); 335 } 336 337 /* 338 * Create a "control" mbuf containing the specified data 339 * with the specified type for presentation with a datagram. 340 */ 341 struct mbuf * 342 udp_saveopt(p, size, type) 343 caddr_t p; 344 register int size; 345 int type; 346 { 347 register struct cmsghdr *cp; 348 struct mbuf *m; 349 350 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 351 return ((struct mbuf *) NULL); 352 cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); 353 bcopy(p, CMSG_DATA(cp), size); 354 size += sizeof(*cp); 355 m->m_len = size; 356 cp->cmsg_len = size; 357 cp->cmsg_level = IPPROTO_IP; 358 cp->cmsg_type = type; 359 return (m); 360 } 361 362 /* 363 * Notify a udp user of an asynchronous error; 364 * just wake up so that he can collect error status. 365 */ 366 static void 367 udp_notify(inp, errno) 368 register struct inpcb *inp; 369 int errno; 370 { 371 inp->inp_socket->so_error = errno; 372 sorwakeup(inp->inp_socket); 373 sowwakeup(inp->inp_socket); 374 } 375 376 void * 377 udp_ctlinput(cmd, sa, v) 378 int cmd; 379 struct sockaddr *sa; 380 void *v; 381 { 382 register struct ip *ip = v; 383 register struct udphdr *uh; 384 extern int inetctlerrmap[]; 385 void (*notify) __P((struct inpcb *, int)) = udp_notify; 386 int errno; 387 388 if ((unsigned)cmd >= PRC_NCMDS) 389 return NULL; 390 errno = inetctlerrmap[cmd]; 391 if (PRC_IS_REDIRECT(cmd)) 392 notify = in_rtchange, ip = 0; 393 else if (cmd == PRC_HOSTDEAD) 394 ip = 0; 395 else if (errno == 0) 396 return NULL; 397 if (ip) { 398 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 399 in_pcbnotify(&udbtable, sa, uh->uh_dport, ip->ip_src, 400 uh->uh_sport, errno, notify); 401 } else 402 in_pcbnotifyall(&udbtable, sa, errno, notify); 403 return NULL; 404 } 405 406 int 407 #if __STDC__ 408 udp_output(struct mbuf *m, ...) 409 #else 410 udp_output(m, va_alist) 411 struct mbuf *m; 412 va_dcl 413 #endif 414 { 415 struct mbuf *control; 416 register struct inpcb *inp; 417 register struct udpiphdr *ui; 418 register int len = m->m_pkthdr.len; 419 int error = 0; 420 va_list ap; 421 422 va_start(ap, m); 423 control = va_arg(ap, struct mbuf *); 424 inp = va_arg(ap, struct inpcb *); 425 va_end(ap); 426 427 if (control) 428 m_freem(control); /* XXX */ 429 430 /* 431 * Calculate data length and get a mbuf 432 * for UDP and IP headers. 433 */ 434 M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT); 435 if (m == 0) { 436 error = ENOBUFS; 437 goto release; 438 } 439 440 /* 441 * Fill in mbuf with extended UDP header 442 * and addresses and length put into network format. 443 */ 444 ui = mtod(m, struct udpiphdr *); 445 bzero(ui->ui_x1, sizeof ui->ui_x1); 446 ui->ui_pr = IPPROTO_UDP; 447 ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr)); 448 ui->ui_src = inp->inp_laddr; 449 ui->ui_dst = inp->inp_faddr; 450 ui->ui_sport = inp->inp_lport; 451 ui->ui_dport = inp->inp_fport; 452 ui->ui_ulen = ui->ui_len; 453 454 /* 455 * Stuff checksum and output datagram. 456 */ 457 ui->ui_sum = 0; 458 if (udpcksum) { 459 if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0) 460 ui->ui_sum = 0xffff; 461 } 462 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 463 ((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */ 464 ((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */ 465 udpstat.udps_opackets++; 466 return (ip_output(m, inp->inp_options, &inp->inp_route, 467 inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST), 468 inp->inp_moptions)); 469 470 release: 471 m_freem(m); 472 return (error); 473 } 474 475 u_long udp_sendspace = 9216; /* really max datagram size */ 476 u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in)); 477 /* 40 1K datagrams */ 478 479 /*ARGSUSED*/ 480 int 481 udp_usrreq(so, req, m, nam, control, p) 482 struct socket *so; 483 int req; 484 struct mbuf *m, *nam, *control; 485 struct proc *p; 486 { 487 register struct inpcb *inp; 488 int s; 489 register int error = 0; 490 491 if (req == PRU_CONTROL) 492 return (in_control(so, (long)m, (caddr_t)nam, 493 (struct ifnet *)control, p)); 494 495 s = splsoftnet(); 496 inp = sotoinpcb(so); 497 if (control && control->m_len) { 498 m_freem(control); 499 error = EINVAL; 500 goto release; 501 } 502 if (inp == 0 && req != PRU_ATTACH) { 503 error = EINVAL; 504 goto release; 505 } 506 507 /* 508 * Note: need to block udp_input while changing 509 * the udp pcb queue and/or pcb addresses. 510 */ 511 switch (req) { 512 513 case PRU_ATTACH: 514 if (inp != 0) { 515 error = EISCONN; 516 break; 517 } 518 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 519 error = soreserve(so, udp_sendspace, udp_recvspace); 520 if (error) 521 break; 522 } 523 error = in_pcballoc(so, &udbtable); 524 if (error) 525 break; 526 inp = sotoinpcb(so); 527 inp->inp_ip.ip_ttl = ip_defttl; 528 break; 529 530 case PRU_DETACH: 531 in_pcbdetach(inp); 532 break; 533 534 case PRU_BIND: 535 error = in_pcbbind(inp, nam, p); 536 break; 537 538 case PRU_LISTEN: 539 error = EOPNOTSUPP; 540 break; 541 542 case PRU_CONNECT: 543 error = in_pcbconnect(inp, nam); 544 if (error) 545 break; 546 soisconnected(so); 547 break; 548 549 case PRU_CONNECT2: 550 error = EOPNOTSUPP; 551 break; 552 553 case PRU_DISCONNECT: 554 /*soisdisconnected(so);*/ 555 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 556 in_pcbdisconnect(inp); 557 inp->inp_laddr.s_addr = INADDR_ANY; /* XXX */ 558 break; 559 560 case PRU_SHUTDOWN: 561 socantsendmore(so); 562 break; 563 564 case PRU_RCVD: 565 error = EOPNOTSUPP; 566 break; 567 568 case PRU_SEND: 569 { 570 struct in_addr laddr; 571 572 if (nam) { 573 laddr = inp->inp_laddr; 574 if ((so->so_state & SS_ISCONNECTED) != 0) { 575 error = EISCONN; 576 break; 577 } 578 error = in_pcbconnect(inp, nam); 579 if (error) 580 break; 581 } else { 582 if ((so->so_state & SS_ISCONNECTED) == 0) { 583 error = ENOTCONN; 584 break; 585 } 586 } 587 error = udp_output(m, control, inp); 588 if (nam) { 589 in_pcbdisconnect(inp); 590 inp->inp_laddr = laddr; 591 } 592 } 593 break; 594 595 case PRU_SENSE: 596 /* 597 * stat: don't bother with a blocksize. 598 */ 599 splx(s); 600 return (0); 601 602 case PRU_RCVOOB: 603 error = EOPNOTSUPP; 604 break; 605 606 case PRU_SENDOOB: 607 m_freem(m); 608 error = EOPNOTSUPP; 609 break; 610 611 case PRU_SOCKADDR: 612 in_setsockaddr(inp, nam); 613 break; 614 615 case PRU_PEERADDR: 616 in_setpeeraddr(inp, nam); 617 break; 618 619 default: 620 panic("udp_usrreq"); 621 } 622 623 release: 624 splx(s); 625 return (error); 626 } 627 628 /* 629 * Sysctl for udp variables. 630 */ 631 int 632 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 633 int *name; 634 u_int namelen; 635 void *oldp; 636 size_t *oldlenp; 637 void *newp; 638 size_t newlen; 639 { 640 /* All sysctl names at this level are terminal. */ 641 if (namelen != 1) 642 return (ENOTDIR); 643 644 switch (name[0]) { 645 case UDPCTL_CHECKSUM: 646 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 647 default: 648 return (ENOPROTOOPT); 649 } 650 /* NOTREACHED */ 651 } 652
Indexes created Fri Sep 26 20:09:58 GMT 2025