udp_usrreq.c revision 1.29
1 /* $NetBSD: udp_usrreq.c,v 1.29 1996/05/20 16:56:20 mrg 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_detach __P((struct inpcb *)); 80 static void udp_notify __P((struct inpcb *, int)); 81 static struct mbuf *udp_saveopt __P((caddr_t, int, int)); 82 83 #ifndef UDBHASHSIZE 84 #define UDBHASHSIZE 128 85 #endif 86 int udbhashsize = UDBHASHSIZE; 87 88 void 89 udp_init() 90 { 91 92 in_pcbinit(&udbtable, udbhashsize); 93 } 94 95 void 96 #if __STDC__ 97 udp_input(struct mbuf *m, ...) 98 #else 99 udp_input(m, va_alist) 100 struct mbuf *m; 101 va_dcl 102 #endif 103 { 104 register struct ip *ip; 105 register struct udphdr *uh; 106 register struct inpcb *inp; 107 struct mbuf *opts = 0; 108 int len; 109 struct ip save_ip; 110 int iphlen; 111 va_list ap; 112 113 va_start(ap, m); 114 iphlen = va_arg(ap, int); 115 va_end(ap); 116 117 udpstat.udps_ipackets++; 118 119 /* 120 * Strip IP options, if any; should skip this, 121 * make available to user, and use on returned packets, 122 * but we don't yet have a way to check the checksum 123 * with options still present. 124 */ 125 if (iphlen > sizeof (struct ip)) { 126 ip_stripoptions(m, (struct mbuf *)0); 127 iphlen = sizeof(struct ip); 128 } 129 130 /* 131 * Get IP and UDP header together in first mbuf. 132 */ 133 ip = mtod(m, struct ip *); 134 if (m->m_len < iphlen + sizeof(struct udphdr)) { 135 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 136 udpstat.udps_hdrops++; 137 return; 138 } 139 ip = mtod(m, struct ip *); 140 } 141 uh = (struct udphdr *)((caddr_t)ip + iphlen); 142 143 /* 144 * Make mbuf data length reflect UDP length. 145 * If not enough data to reflect UDP length, drop. 146 */ 147 len = ntohs((u_int16_t)uh->uh_ulen); 148 if (ip->ip_len != len) { 149 if (len > ip->ip_len) { 150 udpstat.udps_badlen++; 151 goto bad; 152 } 153 m_adj(m, len - ip->ip_len); 154 /* ip->ip_len = len; */ 155 } 156 /* 157 * Save a copy of the IP header in case we want restore it 158 * for sending an ICMP error message in response. 159 */ 160 save_ip = *ip; 161 162 /* 163 * Checksum extended UDP header and data. 164 */ 165 if (uh->uh_sum) { 166 bzero(((struct ipovly *)ip)->ih_x1, 167 sizeof ((struct ipovly *)ip)->ih_x1); 168 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 169 if ((uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) != 0) { 170 udpstat.udps_badsum++; 171 m_freem(m); 172 return; 173 } 174 } 175 176 if (IN_MULTICAST(ip->ip_dst.s_addr) || 177 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 178 struct socket *last; 179 /* 180 * Deliver a multicast or broadcast datagram to *all* sockets 181 * for which the local and remote addresses and ports match 182 * those of the incoming datagram. This allows more than 183 * one process to receive multi/broadcasts on the same port. 184 * (This really ought to be done for unicast datagrams as 185 * well, but that would cause problems with existing 186 * applications that open both address-specific sockets and 187 * a wildcard socket listening to the same port -- they would 188 * end up receiving duplicates of every unicast datagram. 189 * Those applications open the multiple sockets to overcome an 190 * inadequacy of the UDP socket interface, but for backwards 191 * compatibility we avoid the problem here rather than 192 * fixing the interface. Maybe 4.5BSD will remedy this?) 193 */ 194 195 /* 196 * Construct sockaddr format source address. 197 */ 198 udp_in.sin_port = uh->uh_sport; 199 udp_in.sin_addr = ip->ip_src; 200 m->m_len -= sizeof (struct udpiphdr); 201 m->m_data += sizeof (struct udpiphdr); 202 /* 203 * Locate pcb(s) for datagram. 204 * (Algorithm copied from raw_intr().) 205 */ 206 last = NULL; 207 for (inp = udbtable.inpt_queue.cqh_first; 208 inp != (struct inpcb *)&udbtable.inpt_queue; 209 inp = inp->inp_queue.cqe_next) { 210 if (inp->inp_lport != uh->uh_dport) 211 continue; 212 if (inp->inp_laddr.s_addr != INADDR_ANY) { 213 if (inp->inp_laddr.s_addr != 214 ip->ip_dst.s_addr) 215 continue; 216 } 217 if (inp->inp_faddr.s_addr != INADDR_ANY) { 218 if (inp->inp_faddr.s_addr != 219 ip->ip_src.s_addr || 220 inp->inp_fport != uh->uh_sport) 221 continue; 222 } 223 224 if (last != NULL) { 225 struct mbuf *n; 226 227 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) { 228 if (sbappendaddr(&last->so_rcv, 229 sintosa(&udp_in), n, 230 (struct mbuf *)0) == 0) { 231 m_freem(n); 232 udpstat.udps_fullsock++; 233 } else 234 sorwakeup(last); 235 } 236 } 237 last = inp->inp_socket; 238 /* 239 * Don't look for additional matches if this one does 240 * not have either the SO_REUSEPORT or SO_REUSEADDR 241 * socket options set. This heuristic avoids searching 242 * through all pcbs in the common case of a non-shared 243 * port. It * assumes that an application will never 244 * clear these options after setting them. 245 */ 246 if ((last->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0) 247 break; 248 } 249 250 if (last == NULL) { 251 /* 252 * No matching pcb found; discard datagram. 253 * (No need to send an ICMP Port Unreachable 254 * for a broadcast or multicast datgram.) 255 */ 256 udpstat.udps_noportbcast++; 257 goto bad; 258 } 259 if (sbappendaddr(&last->so_rcv, sintosa(&udp_in), m, 260 (struct mbuf *)0) == 0) { 261 udpstat.udps_fullsock++; 262 goto bad; 263 } 264 sorwakeup(last); 265 return; 266 } 267 /* 268 * Locate pcb for datagram. 269 */ 270 inp = in_pcbhashlookup(&udbtable, ip->ip_src, uh->uh_sport, 271 ip->ip_dst, uh->uh_dport); 272 if (inp == 0) { 273 ++udpstat.udps_pcbhashmiss; 274 inp = in_pcblookup(&udbtable, ip->ip_src, uh->uh_sport, 275 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD); 276 if (inp == 0) { 277 udpstat.udps_noport++; 278 if (m->m_flags & (M_BCAST | M_MCAST)) { 279 udpstat.udps_noportbcast++; 280 goto bad; 281 } 282 *ip = save_ip; 283 ip->ip_len += iphlen; 284 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 285 return; 286 } 287 } 288 289 /* 290 * Construct sockaddr format source address. 291 * Stuff source address and datagram in user buffer. 292 */ 293 udp_in.sin_port = uh->uh_sport; 294 udp_in.sin_addr = ip->ip_src; 295 if (inp->inp_flags & INP_CONTROLOPTS) { 296 struct mbuf **mp = &opts; 297 298 if (inp->inp_flags & INP_RECVDSTADDR) { 299 *mp = udp_saveopt((caddr_t) &ip->ip_dst, 300 sizeof(struct in_addr), IP_RECVDSTADDR); 301 if (*mp) 302 mp = &(*mp)->m_next; 303 } 304 #ifdef notyet 305 /* options were tossed above */ 306 if (inp->inp_flags & INP_RECVOPTS) { 307 *mp = udp_saveopt((caddr_t) opts_deleted_above, 308 sizeof(struct in_addr), IP_RECVOPTS); 309 if (*mp) 310 mp = &(*mp)->m_next; 311 } 312 /* ip_srcroute doesn't do what we want here, need to fix */ 313 if (inp->inp_flags & INP_RECVRETOPTS) { 314 *mp = udp_saveopt((caddr_t) ip_srcroute(), 315 sizeof(struct in_addr), IP_RECVRETOPTS); 316 if (*mp) 317 mp = &(*mp)->m_next; 318 } 319 #endif 320 } 321 iphlen += sizeof(struct udphdr); 322 m->m_len -= iphlen; 323 m->m_pkthdr.len -= iphlen; 324 m->m_data += iphlen; 325 if (sbappendaddr(&inp->inp_socket->so_rcv, sintosa(&udp_in), m, 326 opts) == 0) { 327 udpstat.udps_fullsock++; 328 goto bad; 329 } 330 sorwakeup(inp->inp_socket); 331 return; 332 bad: 333 m_freem(m); 334 if (opts) 335 m_freem(opts); 336 } 337 338 /* 339 * Create a "control" mbuf containing the specified data 340 * with the specified type for presentation with a datagram. 341 */ 342 struct mbuf * 343 udp_saveopt(p, size, type) 344 caddr_t p; 345 register int size; 346 int type; 347 { 348 register struct cmsghdr *cp; 349 struct mbuf *m; 350 351 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 352 return ((struct mbuf *) NULL); 353 cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); 354 bcopy(p, CMSG_DATA(cp), size); 355 size += sizeof(*cp); 356 m->m_len = size; 357 cp->cmsg_len = size; 358 cp->cmsg_level = IPPROTO_IP; 359 cp->cmsg_type = type; 360 return (m); 361 } 362 363 /* 364 * Notify a udp user of an asynchronous error; 365 * just wake up so that he can collect error status. 366 */ 367 static void 368 udp_notify(inp, errno) 369 register struct inpcb *inp; 370 int errno; 371 { 372 inp->inp_socket->so_error = errno; 373 sorwakeup(inp->inp_socket); 374 sowwakeup(inp->inp_socket); 375 } 376 377 void * 378 udp_ctlinput(cmd, sa, v) 379 int cmd; 380 struct sockaddr *sa; 381 void *v; 382 { 383 register struct ip *ip = v; 384 register struct udphdr *uh; 385 extern int inetctlerrmap[]; 386 void (*notify) __P((struct inpcb *, int)) = udp_notify; 387 int errno; 388 389 if ((unsigned)cmd >= PRC_NCMDS) 390 return NULL; 391 errno = inetctlerrmap[cmd]; 392 if (PRC_IS_REDIRECT(cmd)) 393 notify = in_rtchange, ip = 0; 394 else if (cmd == PRC_HOSTDEAD) 395 ip = 0; 396 else if (errno == 0) 397 return NULL; 398 if (ip) { 399 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 400 in_pcbnotify(&udbtable, sa, uh->uh_dport, ip->ip_src, 401 uh->uh_sport, errno, notify); 402 } else 403 in_pcbnotifyall(&udbtable, sa, errno, notify); 404 return NULL; 405 } 406 407 int 408 #if __STDC__ 409 udp_output(struct mbuf *m, ...) 410 #else 411 udp_output(m, va_alist) 412 struct mbuf *m; 413 va_dcl 414 #endif 415 { 416 register struct inpcb *inp; 417 struct mbuf *addr, *control; 418 register struct udpiphdr *ui; 419 register int len = m->m_pkthdr.len; 420 struct in_addr laddr; 421 int s = 0, error = 0; 422 va_list ap; 423 424 va_start(ap, m); 425 inp = va_arg(ap, struct inpcb *); 426 addr = va_arg(ap, struct mbuf *); 427 control = va_arg(ap, struct mbuf *); 428 va_end(ap); 429 430 if (control) 431 m_freem(control); /* XXX */ 432 433 if (addr) { 434 laddr = inp->inp_laddr; 435 if (inp->inp_faddr.s_addr != INADDR_ANY) { 436 error = EISCONN; 437 goto release; 438 } 439 /* 440 * Must block input while temporarily connected. 441 */ 442 s = splsoftnet(); 443 error = in_pcbconnect(inp, addr); 444 if (error) { 445 splx(s); 446 goto release; 447 } 448 } else { 449 if (inp->inp_faddr.s_addr == INADDR_ANY) { 450 error = ENOTCONN; 451 goto release; 452 } 453 } 454 /* 455 * Calculate data length and get a mbuf 456 * for UDP and IP headers. 457 */ 458 M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT); 459 if (m == 0) { 460 error = ENOBUFS; 461 goto release; 462 } 463 464 /* 465 * Fill in mbuf with extended UDP header 466 * and addresses and length put into network format. 467 */ 468 ui = mtod(m, struct udpiphdr *); 469 bzero(ui->ui_x1, sizeof ui->ui_x1); 470 ui->ui_pr = IPPROTO_UDP; 471 ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr)); 472 ui->ui_src = inp->inp_laddr; 473 ui->ui_dst = inp->inp_faddr; 474 ui->ui_sport = inp->inp_lport; 475 ui->ui_dport = inp->inp_fport; 476 ui->ui_ulen = ui->ui_len; 477 478 /* 479 * Stuff checksum and output datagram. 480 */ 481 ui->ui_sum = 0; 482 if (udpcksum) { 483 if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0) 484 ui->ui_sum = 0xffff; 485 } 486 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 487 ((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */ 488 ((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */ 489 udpstat.udps_opackets++; 490 error = ip_output(m, inp->inp_options, &inp->inp_route, 491 inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST), 492 inp->inp_moptions); 493 494 if (addr) { 495 in_pcbdisconnect(inp); 496 inp->inp_laddr = laddr; 497 splx(s); 498 } 499 return (error); 500 501 release: 502 m_freem(m); 503 return (error); 504 } 505 506 u_long udp_sendspace = 9216; /* really max datagram size */ 507 u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in)); 508 /* 40 1K datagrams */ 509 510 /*ARGSUSED*/ 511 int 512 udp_usrreq(so, req, m, addr, control) 513 struct socket *so; 514 int req; 515 struct mbuf *m, *addr, *control; 516 { 517 struct inpcb *inp = sotoinpcb(so); 518 int error = 0; 519 int s; 520 521 if (req == PRU_CONTROL) 522 return (in_control(so, (long)m, (caddr_t)addr, 523 (struct ifnet *)control)); 524 if (inp == NULL && req != PRU_ATTACH) { 525 error = EINVAL; 526 goto release; 527 } 528 /* 529 * Note: need to block udp_input while changing 530 * the udp pcb queue and/or pcb addresses. 531 */ 532 switch (req) { 533 534 case PRU_ATTACH: 535 if (inp != NULL) { 536 error = EINVAL; 537 break; 538 } 539 s = splsoftnet(); 540 error = in_pcballoc(so, &udbtable); 541 splx(s); 542 if (error) 543 break; 544 error = soreserve(so, udp_sendspace, udp_recvspace); 545 if (error) 546 break; 547 ((struct inpcb *) so->so_pcb)->inp_ip.ip_ttl = ip_defttl; 548 break; 549 550 case PRU_DETACH: 551 udp_detach(inp); 552 break; 553 554 case PRU_BIND: 555 s = splsoftnet(); 556 error = in_pcbbind(inp, addr); 557 splx(s); 558 break; 559 560 case PRU_LISTEN: 561 error = EOPNOTSUPP; 562 break; 563 564 case PRU_CONNECT: 565 if (inp->inp_faddr.s_addr != INADDR_ANY) { 566 error = EISCONN; 567 break; 568 } 569 s = splsoftnet(); 570 error = in_pcbconnect(inp, addr); 571 splx(s); 572 if (error == 0) 573 soisconnected(so); 574 break; 575 576 case PRU_CONNECT2: 577 error = EOPNOTSUPP; 578 break; 579 580 case PRU_ACCEPT: 581 error = EOPNOTSUPP; 582 break; 583 584 case PRU_DISCONNECT: 585 if (inp->inp_faddr.s_addr == INADDR_ANY) { 586 error = ENOTCONN; 587 break; 588 } 589 s = splsoftnet(); 590 in_pcbdisconnect(inp); 591 inp->inp_laddr.s_addr = INADDR_ANY; 592 splx(s); 593 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 594 break; 595 596 case PRU_SHUTDOWN: 597 socantsendmore(so); 598 break; 599 600 case PRU_SEND: 601 return (udp_output(m, inp, addr, control)); 602 603 case PRU_ABORT: 604 soisdisconnected(so); 605 udp_detach(inp); 606 break; 607 608 case PRU_SOCKADDR: 609 in_setsockaddr(inp, addr); 610 break; 611 612 case PRU_PEERADDR: 613 in_setpeeraddr(inp, addr); 614 break; 615 616 case PRU_SENSE: 617 /* 618 * stat: don't bother with a blocksize. 619 */ 620 return (0); 621 622 case PRU_SENDOOB: 623 case PRU_FASTTIMO: 624 case PRU_SLOWTIMO: 625 case PRU_PROTORCV: 626 case PRU_PROTOSEND: 627 error = EOPNOTSUPP; 628 break; 629 630 case PRU_RCVD: 631 case PRU_RCVOOB: 632 return (EOPNOTSUPP); /* do not free mbuf's */ 633 634 default: 635 panic("udp_usrreq"); 636 } 637 638 release: 639 if (control) { 640 printf("udp control data unexpectedly retained\n"); 641 m_freem(control); 642 } 643 if (m) 644 m_freem(m); 645 return (error); 646 } 647 648 static void 649 udp_detach(inp) 650 struct inpcb *inp; 651 { 652 int s = splsoftnet(); 653 654 in_pcbdetach(inp); 655 splx(s); 656 } 657 658 /* 659 * Sysctl for udp variables. 660 */ 661 int 662 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 663 int *name; 664 u_int namelen; 665 void *oldp; 666 size_t *oldlenp; 667 void *newp; 668 size_t newlen; 669 { 670 /* All sysctl names at this level are terminal. */ 671 if (namelen != 1) 672 return (ENOTDIR); 673 674 switch (name[0]) { 675 case UDPCTL_CHECKSUM: 676 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 677 default: 678 return (ENOPROTOOPT); 679 } 680 /* NOTREACHED */ 681 } 682
Indexes created Sun Sep 21 20:09:37 GMT 2025