udp_usrreq.c revision 1.23
1 /* $NetBSD: udp_usrreq.c,v 1.23 1995/06/26 08:46:16 cgd 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 47 #include <net/if.h> 48 #include <net/route.h> 49 50 #include <netinet/in.h> 51 #include <netinet/in_systm.h> 52 #include <netinet/in_var.h> 53 #include <netinet/ip.h> 54 #include <netinet/in_pcb.h> 55 #include <netinet/ip_var.h> 56 #include <netinet/ip_icmp.h> 57 #include <netinet/udp.h> 58 #include <netinet/udp_var.h> 59 60 /* 61 * UDP protocol implementation. 62 * Per RFC 768, August, 1980. 63 */ 64 #ifndef COMPAT_42 65 int udpcksum = 1; 66 #else 67 int udpcksum = 0; /* XXX */ 68 #endif 69 70 struct sockaddr_in udp_in = { sizeof(udp_in), AF_INET }; 71 struct inpcb *udp_last_inpcb = 0; 72 73 static void udp_detach __P((struct inpcb *)); 74 static void udp_notify __P((struct inpcb *, int)); 75 static struct mbuf *udp_saveopt __P((caddr_t, int, int)); 76 77 void 78 udp_init() 79 { 80 81 in_pcbinit(&udbtable); 82 } 83 84 void 85 udp_input(m, iphlen) 86 register struct mbuf *m; 87 int iphlen; 88 { 89 register struct ip *ip; 90 register struct udphdr *uh; 91 register struct inpcb *inp; 92 struct mbuf *opts = 0; 93 int len; 94 struct ip save_ip; 95 96 udpstat.udps_ipackets++; 97 98 /* 99 * Strip IP options, if any; should skip this, 100 * make available to user, and use on returned packets, 101 * but we don't yet have a way to check the checksum 102 * with options still present. 103 */ 104 if (iphlen > sizeof (struct ip)) { 105 ip_stripoptions(m, (struct mbuf *)0); 106 iphlen = sizeof(struct ip); 107 } 108 109 /* 110 * Get IP and UDP header together in first mbuf. 111 */ 112 ip = mtod(m, struct ip *); 113 if (m->m_len < iphlen + sizeof(struct udphdr)) { 114 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 115 udpstat.udps_hdrops++; 116 return; 117 } 118 ip = mtod(m, struct ip *); 119 } 120 uh = (struct udphdr *)((caddr_t)ip + iphlen); 121 122 /* 123 * Make mbuf data length reflect UDP length. 124 * If not enough data to reflect UDP length, drop. 125 */ 126 len = ntohs((u_int16_t)uh->uh_ulen); 127 if (ip->ip_len != len) { 128 if (len > ip->ip_len) { 129 udpstat.udps_badlen++; 130 goto bad; 131 } 132 m_adj(m, len - ip->ip_len); 133 /* ip->ip_len = len; */ 134 } 135 /* 136 * Save a copy of the IP header in case we want restore it 137 * for sending an ICMP error message in response. 138 */ 139 save_ip = *ip; 140 141 /* 142 * Checksum extended UDP header and data. 143 */ 144 if (udpcksum && uh->uh_sum) { 145 ((struct ipovly *)ip)->ih_next = 0; 146 ((struct ipovly *)ip)->ih_prev = 0; 147 ((struct ipovly *)ip)->ih_x1 = 0; 148 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 149 if (uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) { 150 udpstat.udps_badsum++; 151 m_freem(m); 152 return; 153 } 154 } 155 156 if (IN_MULTICAST(ip->ip_dst.s_addr) || 157 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 158 struct socket *last; 159 /* 160 * Deliver a multicast or broadcast datagram to *all* sockets 161 * for which the local and remote addresses and ports match 162 * those of the incoming datagram. This allows more than 163 * one process to receive multi/broadcasts on the same port. 164 * (This really ought to be done for unicast datagrams as 165 * well, but that would cause problems with existing 166 * applications that open both address-specific sockets and 167 * a wildcard socket listening to the same port -- they would 168 * end up receiving duplicates of every unicast datagram. 169 * Those applications open the multiple sockets to overcome an 170 * inadequacy of the UDP socket interface, but for backwards 171 * compatibility we avoid the problem here rather than 172 * fixing the interface. Maybe 4.5BSD will remedy this?) 173 */ 174 175 /* 176 * Construct sockaddr format source address. 177 */ 178 udp_in.sin_port = uh->uh_sport; 179 udp_in.sin_addr = ip->ip_src; 180 m->m_len -= sizeof (struct udpiphdr); 181 m->m_data += sizeof (struct udpiphdr); 182 /* 183 * Locate pcb(s) for datagram. 184 * (Algorithm copied from raw_intr().) 185 */ 186 last = NULL; 187 for (inp = udbtable.inpt_queue.cqh_first; 188 inp != (struct inpcb *)&udbtable.inpt_queue; 189 inp = inp->inp_queue.cqe_next) { 190 if (inp->inp_lport != uh->uh_dport) 191 continue; 192 if (inp->inp_laddr.s_addr != INADDR_ANY) { 193 if (inp->inp_laddr.s_addr != 194 ip->ip_dst.s_addr) 195 continue; 196 } 197 if (inp->inp_faddr.s_addr != INADDR_ANY) { 198 if (inp->inp_faddr.s_addr != 199 ip->ip_src.s_addr || 200 inp->inp_fport != uh->uh_sport) 201 continue; 202 } 203 204 if (last != NULL) { 205 struct mbuf *n; 206 207 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) { 208 if (sbappendaddr(&last->so_rcv, 209 sintosa(&udp_in), n, 210 (struct mbuf *)0) == 0) { 211 m_freem(n); 212 udpstat.udps_fullsock++; 213 } else 214 sorwakeup(last); 215 } 216 } 217 last = inp->inp_socket; 218 /* 219 * Don't look for additional matches if this one does 220 * not have either the SO_REUSEPORT or SO_REUSEADDR 221 * socket options set. This heuristic avoids searching 222 * through all pcbs in the common case of a non-shared 223 * port. It * assumes that an application will never 224 * clear these options after setting them. 225 */ 226 if ((last->so_options&(SO_REUSEPORT|SO_REUSEADDR) == 0)) 227 break; 228 } 229 230 if (last == NULL) { 231 /* 232 * No matching pcb found; discard datagram. 233 * (No need to send an ICMP Port Unreachable 234 * for a broadcast or multicast datgram.) 235 */ 236 udpstat.udps_noportbcast++; 237 goto bad; 238 } 239 if (sbappendaddr(&last->so_rcv, sintosa(&udp_in), m, 240 (struct mbuf *)0) == 0) { 241 udpstat.udps_fullsock++; 242 goto bad; 243 } 244 sorwakeup(last); 245 return; 246 } 247 /* 248 * Locate pcb for datagram. 249 */ 250 inp = udp_last_inpcb; 251 if (inp == 0 || 252 inp->inp_lport != uh->uh_dport || 253 inp->inp_fport != uh->uh_sport || 254 inp->inp_faddr.s_addr != ip->ip_src.s_addr || 255 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) { 256 udpstat.udpps_pcbcachemiss++; 257 inp = in_pcblookup(&udbtable, ip->ip_src, uh->uh_sport, 258 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD); 259 if (inp == 0) { 260 udpstat.udps_noport++; 261 if (m->m_flags & (M_BCAST | M_MCAST)) { 262 udpstat.udps_noportbcast++; 263 goto bad; 264 } 265 *ip = save_ip; 266 ip->ip_len += iphlen; 267 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 268 return; 269 } 270 udp_last_inpcb = inp; 271 } 272 273 /* 274 * Construct sockaddr format source address. 275 * Stuff source address and datagram in user buffer. 276 */ 277 udp_in.sin_port = uh->uh_sport; 278 udp_in.sin_addr = ip->ip_src; 279 if (inp->inp_flags & INP_CONTROLOPTS) { 280 struct mbuf **mp = &opts; 281 282 if (inp->inp_flags & INP_RECVDSTADDR) { 283 *mp = udp_saveopt((caddr_t) &ip->ip_dst, 284 sizeof(struct in_addr), IP_RECVDSTADDR); 285 if (*mp) 286 mp = &(*mp)->m_next; 287 } 288 #ifdef notyet 289 /* options were tossed above */ 290 if (inp->inp_flags & INP_RECVOPTS) { 291 *mp = udp_saveopt((caddr_t) opts_deleted_above, 292 sizeof(struct in_addr), IP_RECVOPTS); 293 if (*mp) 294 mp = &(*mp)->m_next; 295 } 296 /* ip_srcroute doesn't do what we want here, need to fix */ 297 if (inp->inp_flags & INP_RECVRETOPTS) { 298 *mp = udp_saveopt((caddr_t) ip_srcroute(), 299 sizeof(struct in_addr), IP_RECVRETOPTS); 300 if (*mp) 301 mp = &(*mp)->m_next; 302 } 303 #endif 304 } 305 iphlen += sizeof(struct udphdr); 306 m->m_len -= iphlen; 307 m->m_pkthdr.len -= iphlen; 308 m->m_data += iphlen; 309 if (sbappendaddr(&inp->inp_socket->so_rcv, sintosa(&udp_in), m, 310 opts) == 0) { 311 udpstat.udps_fullsock++; 312 goto bad; 313 } 314 sorwakeup(inp->inp_socket); 315 return; 316 bad: 317 m_freem(m); 318 if (opts) 319 m_freem(opts); 320 } 321 322 /* 323 * Create a "control" mbuf containing the specified data 324 * with the specified type for presentation with a datagram. 325 */ 326 struct mbuf * 327 udp_saveopt(p, size, type) 328 caddr_t p; 329 register int size; 330 int type; 331 { 332 register struct cmsghdr *cp; 333 struct mbuf *m; 334 335 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 336 return ((struct mbuf *) NULL); 337 cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); 338 bcopy(p, CMSG_DATA(cp), size); 339 size += sizeof(*cp); 340 m->m_len = size; 341 cp->cmsg_len = size; 342 cp->cmsg_level = IPPROTO_IP; 343 cp->cmsg_type = type; 344 return (m); 345 } 346 347 /* 348 * Notify a udp user of an asynchronous error; 349 * just wake up so that he can collect error status. 350 */ 351 static void 352 udp_notify(inp, errno) 353 register struct inpcb *inp; 354 int errno; 355 { 356 inp->inp_socket->so_error = errno; 357 sorwakeup(inp->inp_socket); 358 sowwakeup(inp->inp_socket); 359 } 360 361 void 362 udp_ctlinput(cmd, sa, ip) 363 int cmd; 364 struct sockaddr *sa; 365 register struct ip *ip; 366 { 367 register struct udphdr *uh; 368 extern struct in_addr zeroin_addr; 369 extern int inetctlerrmap[]; 370 void (*notify) __P((struct inpcb *, int)) = udp_notify; 371 int errno; 372 373 if ((unsigned)cmd >= PRC_NCMDS) 374 return; 375 errno = inetctlerrmap[cmd]; 376 if (PRC_IS_REDIRECT(cmd)) 377 notify = in_rtchange, ip = 0; 378 else if (cmd == PRC_HOSTDEAD) 379 ip = 0; 380 else if (errno == 0) 381 return; 382 if (ip) { 383 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 384 in_pcbnotify(&udbtable, sa, uh->uh_dport, ip->ip_src, 385 uh->uh_sport, errno, notify); 386 } else 387 in_pcbnotifyall(&udbtable, sa, errno, notify); 388 } 389 390 int 391 udp_output(inp, m, addr, control) 392 register struct inpcb *inp; 393 register struct mbuf *m; 394 struct mbuf *addr, *control; 395 { 396 register struct udpiphdr *ui; 397 register int len = m->m_pkthdr.len; 398 struct in_addr laddr; 399 int s, error = 0; 400 401 if (control) 402 m_freem(control); /* XXX */ 403 404 if (addr) { 405 laddr = inp->inp_laddr; 406 if (inp->inp_faddr.s_addr != INADDR_ANY) { 407 error = EISCONN; 408 goto release; 409 } 410 /* 411 * Must block input while temporarily connected. 412 */ 413 s = splnet(); 414 error = in_pcbconnect(inp, addr); 415 if (error) { 416 splx(s); 417 goto release; 418 } 419 } else { 420 if (inp->inp_faddr.s_addr == INADDR_ANY) { 421 error = ENOTCONN; 422 goto release; 423 } 424 } 425 /* 426 * Calculate data length and get a mbuf 427 * for UDP and IP headers. 428 */ 429 M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT); 430 if (m == 0) { 431 error = ENOBUFS; 432 goto release; 433 } 434 435 /* 436 * Fill in mbuf with extended UDP header 437 * and addresses and length put into network format. 438 */ 439 ui = mtod(m, struct udpiphdr *); 440 ui->ui_next = ui->ui_prev = 0; 441 ui->ui_x1 = 0; 442 ui->ui_pr = IPPROTO_UDP; 443 ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr)); 444 ui->ui_src = inp->inp_laddr; 445 ui->ui_dst = inp->inp_faddr; 446 ui->ui_sport = inp->inp_lport; 447 ui->ui_dport = inp->inp_fport; 448 ui->ui_ulen = ui->ui_len; 449 450 /* 451 * Stuff checksum and output datagram. 452 */ 453 ui->ui_sum = 0; 454 if (udpcksum) { 455 if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0) 456 ui->ui_sum = 0xffff; 457 } 458 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 459 ((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */ 460 ((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */ 461 udpstat.udps_opackets++; 462 error = ip_output(m, inp->inp_options, &inp->inp_route, 463 inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST), 464 inp->inp_moptions); 465 466 if (addr) { 467 in_pcbdisconnect(inp); 468 inp->inp_laddr = laddr; 469 splx(s); 470 } 471 return (error); 472 473 release: 474 m_freem(m); 475 return (error); 476 } 477 478 u_long udp_sendspace = 9216; /* really max datagram size */ 479 u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in)); 480 /* 40 1K datagrams */ 481 482 /*ARGSUSED*/ 483 int 484 udp_usrreq(so, req, m, addr, control) 485 struct socket *so; 486 int req; 487 struct mbuf *m, *addr, *control; 488 { 489 struct inpcb *inp = sotoinpcb(so); 490 int error = 0; 491 int s; 492 493 if (req == PRU_CONTROL) 494 return (in_control(so, (long)m, (caddr_t)addr, 495 (struct ifnet *)control)); 496 if (inp == NULL && req != PRU_ATTACH) { 497 error = EINVAL; 498 goto release; 499 } 500 /* 501 * Note: need to block udp_input while changing 502 * the udp pcb queue and/or pcb addresses. 503 */ 504 switch (req) { 505 506 case PRU_ATTACH: 507 if (inp != NULL) { 508 error = EINVAL; 509 break; 510 } 511 s = splnet(); 512 error = in_pcballoc(so, &udbtable); 513 splx(s); 514 if (error) 515 break; 516 error = soreserve(so, udp_sendspace, udp_recvspace); 517 if (error) 518 break; 519 ((struct inpcb *) so->so_pcb)->inp_ip.ip_ttl = ip_defttl; 520 break; 521 522 case PRU_DETACH: 523 udp_detach(inp); 524 break; 525 526 case PRU_BIND: 527 s = splnet(); 528 error = in_pcbbind(inp, addr); 529 splx(s); 530 break; 531 532 case PRU_LISTEN: 533 error = EOPNOTSUPP; 534 break; 535 536 case PRU_CONNECT: 537 if (inp->inp_faddr.s_addr != INADDR_ANY) { 538 error = EISCONN; 539 break; 540 } 541 s = splnet(); 542 error = in_pcbconnect(inp, addr); 543 splx(s); 544 if (error == 0) 545 soisconnected(so); 546 break; 547 548 case PRU_CONNECT2: 549 error = EOPNOTSUPP; 550 break; 551 552 case PRU_ACCEPT: 553 error = EOPNOTSUPP; 554 break; 555 556 case PRU_DISCONNECT: 557 if (inp->inp_faddr.s_addr == INADDR_ANY) { 558 error = ENOTCONN; 559 break; 560 } 561 s = splnet(); 562 in_pcbdisconnect(inp); 563 inp->inp_laddr.s_addr = INADDR_ANY; 564 splx(s); 565 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 566 break; 567 568 case PRU_SHUTDOWN: 569 socantsendmore(so); 570 break; 571 572 case PRU_SEND: 573 return (udp_output(inp, m, addr, control)); 574 575 case PRU_ABORT: 576 soisdisconnected(so); 577 udp_detach(inp); 578 break; 579 580 case PRU_SOCKADDR: 581 in_setsockaddr(inp, addr); 582 break; 583 584 case PRU_PEERADDR: 585 in_setpeeraddr(inp, addr); 586 break; 587 588 case PRU_SENSE: 589 /* 590 * stat: don't bother with a blocksize. 591 */ 592 return (0); 593 594 case PRU_SENDOOB: 595 case PRU_FASTTIMO: 596 case PRU_SLOWTIMO: 597 case PRU_PROTORCV: 598 case PRU_PROTOSEND: 599 error = EOPNOTSUPP; 600 break; 601 602 case PRU_RCVD: 603 case PRU_RCVOOB: 604 return (EOPNOTSUPP); /* do not free mbuf's */ 605 606 default: 607 panic("udp_usrreq"); 608 } 609 610 release: 611 if (control) { 612 printf("udp control data unexpectedly retained\n"); 613 m_freem(control); 614 } 615 if (m) 616 m_freem(m); 617 return (error); 618 } 619 620 static void 621 udp_detach(inp) 622 struct inpcb *inp; 623 { 624 int s = splnet(); 625 626 if (inp == udp_last_inpcb) 627 udp_last_inpcb = 0; 628 in_pcbdetach(inp); 629 splx(s); 630 } 631 632 /* 633 * Sysctl for udp variables. 634 */ 635 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 636 int *name; 637 u_int namelen; 638 void *oldp; 639 size_t *oldlenp; 640 void *newp; 641 size_t newlen; 642 { 643 /* All sysctl names at this level are terminal. */ 644 if (namelen != 1) 645 return (ENOTDIR); 646 647 switch (name[0]) { 648 case UDPCTL_CHECKSUM: 649 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 650 default: 651 return (ENOPROTOOPT); 652 } 653 /* NOTREACHED */ 654 } 655
Indexes created Mon Sep 22 05:09:51 GMT 2025