udp_usrreq.c revision 1.24.2.1
1 /* $NetBSD: udp_usrreq.c,v 1.24.2.1 1996/02/02 06:13:02 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 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 72 static void udp_detach __P((struct inpcb *)); 73 static void udp_notify __P((struct inpcb *, int)); 74 static struct mbuf *udp_saveopt __P((caddr_t, int, int)); 75 76 #ifndef UDBHASHSIZE 77 #define UDBHASHSIZE 128 78 #endif 79 int udbhashsize = UDBHASHSIZE; 80 81 void 82 udp_init() 83 { 84 85 in_pcbinit(&udbtable, udbhashsize); 86 } 87 88 void 89 udp_input(m, iphlen) 90 register struct mbuf *m; 91 int iphlen; 92 { 93 register struct ip *ip; 94 register struct udphdr *uh; 95 register struct inpcb *inp; 96 struct mbuf *opts = 0; 97 int len; 98 struct ip save_ip; 99 100 udpstat.udps_ipackets++; 101 102 /* 103 * Strip IP options, if any; should skip this, 104 * make available to user, and use on returned packets, 105 * but we don't yet have a way to check the checksum 106 * with options still present. 107 */ 108 if (iphlen > sizeof (struct ip)) { 109 ip_stripoptions(m, (struct mbuf *)0); 110 iphlen = sizeof(struct ip); 111 } 112 113 /* 114 * Get IP and UDP header together in first mbuf. 115 */ 116 ip = mtod(m, struct ip *); 117 if (m->m_len < iphlen + sizeof(struct udphdr)) { 118 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 119 udpstat.udps_hdrops++; 120 return; 121 } 122 ip = mtod(m, struct ip *); 123 } 124 uh = (struct udphdr *)((caddr_t)ip + iphlen); 125 126 /* 127 * Make mbuf data length reflect UDP length. 128 * If not enough data to reflect UDP length, drop. 129 */ 130 len = ntohs((u_int16_t)uh->uh_ulen); 131 if (ip->ip_len != len) { 132 if (len > ip->ip_len) { 133 udpstat.udps_badlen++; 134 goto bad; 135 } 136 m_adj(m, len - ip->ip_len); 137 /* ip->ip_len = len; */ 138 } 139 /* 140 * Save a copy of the IP header in case we want restore it 141 * for sending an ICMP error message in response. 142 */ 143 save_ip = *ip; 144 145 /* 146 * Checksum extended UDP header and data. 147 */ 148 if (udpcksum && uh->uh_sum) { 149 ((struct ipovly *)ip)->ih_next = 0; 150 ((struct ipovly *)ip)->ih_prev = 0; 151 ((struct ipovly *)ip)->ih_x1 = 0; 152 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 153 if (uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) { 154 udpstat.udps_badsum++; 155 m_freem(m); 156 return; 157 } 158 } 159 160 if (IN_MULTICAST(ip->ip_dst.s_addr) || 161 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 162 struct socket *last; 163 /* 164 * Deliver a multicast or broadcast datagram to *all* sockets 165 * for which the local and remote addresses and ports match 166 * those of the incoming datagram. This allows more than 167 * one process to receive multi/broadcasts on the same port. 168 * (This really ought to be done for unicast datagrams as 169 * well, but that would cause problems with existing 170 * applications that open both address-specific sockets and 171 * a wildcard socket listening to the same port -- they would 172 * end up receiving duplicates of every unicast datagram. 173 * Those applications open the multiple sockets to overcome an 174 * inadequacy of the UDP socket interface, but for backwards 175 * compatibility we avoid the problem here rather than 176 * fixing the interface. Maybe 4.5BSD will remedy this?) 177 */ 178 179 /* 180 * Construct sockaddr format source address. 181 */ 182 udp_in.sin_port = uh->uh_sport; 183 udp_in.sin_addr = ip->ip_src; 184 m->m_len -= sizeof (struct udpiphdr); 185 m->m_data += sizeof (struct udpiphdr); 186 /* 187 * Locate pcb(s) for datagram. 188 * (Algorithm copied from raw_intr().) 189 */ 190 last = NULL; 191 for (inp = udbtable.inpt_queue.cqh_first; 192 inp != (struct inpcb *)&udbtable.inpt_queue; 193 inp = inp->inp_queue.cqe_next) { 194 if (inp->inp_lport != uh->uh_dport) 195 continue; 196 if (inp->inp_laddr.s_addr != INADDR_ANY) { 197 if (inp->inp_laddr.s_addr != 198 ip->ip_dst.s_addr) 199 continue; 200 } 201 if (inp->inp_faddr.s_addr != INADDR_ANY) { 202 if (inp->inp_faddr.s_addr != 203 ip->ip_src.s_addr || 204 inp->inp_fport != uh->uh_sport) 205 continue; 206 } 207 208 if (last != NULL) { 209 struct mbuf *n; 210 211 if ((n = m_copy(m, 0, M_COPYALL)) != NULL) { 212 if (sbappendaddr(&last->so_rcv, 213 sintosa(&udp_in), n, 214 (struct mbuf *)0) == 0) { 215 m_freem(n); 216 udpstat.udps_fullsock++; 217 } else 218 sorwakeup(last); 219 } 220 } 221 last = inp->inp_socket; 222 /* 223 * Don't look for additional matches if this one does 224 * not have either the SO_REUSEPORT or SO_REUSEADDR 225 * socket options set. This heuristic avoids searching 226 * through all pcbs in the common case of a non-shared 227 * port. It * assumes that an application will never 228 * clear these options after setting them. 229 */ 230 if ((last->so_options&(SO_REUSEPORT|SO_REUSEADDR) == 0)) 231 break; 232 } 233 234 if (last == NULL) { 235 /* 236 * No matching pcb found; discard datagram. 237 * (No need to send an ICMP Port Unreachable 238 * for a broadcast or multicast datgram.) 239 */ 240 udpstat.udps_noportbcast++; 241 goto bad; 242 } 243 if (sbappendaddr(&last->so_rcv, sintosa(&udp_in), m, 244 (struct mbuf *)0) == 0) { 245 udpstat.udps_fullsock++; 246 goto bad; 247 } 248 sorwakeup(last); 249 return; 250 } 251 /* 252 * Locate pcb for datagram. 253 */ 254 inp = in_pcbhashlookup(&udbtable, ip->ip_src, uh->uh_sport, 255 ip->ip_dst, uh->uh_dport); 256 if (inp == 0) { 257 ++udpstat.udps_pcbhashmiss; 258 inp = in_pcblookup(&udbtable, ip->ip_src, uh->uh_sport, 259 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD); 260 if (inp == 0) { 261 udpstat.udps_noport++; 262 if (m->m_flags & (M_BCAST | M_MCAST)) { 263 udpstat.udps_noportbcast++; 264 goto bad; 265 } 266 *ip = save_ip; 267 ip->ip_len += iphlen; 268 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 269 return; 270 } 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 = splsoftnet(); 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 = splsoftnet(); 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 = splsoftnet(); 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 = splsoftnet(); 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 = splsoftnet(); 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 = splsoftnet(); 625 626 in_pcbdetach(inp); 627 splx(s); 628 } 629 630 /* 631 * Sysctl for udp variables. 632 */ 633 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 634 int *name; 635 u_int namelen; 636 void *oldp; 637 size_t *oldlenp; 638 void *newp; 639 size_t newlen; 640 { 641 /* All sysctl names at this level are terminal. */ 642 if (namelen != 1) 643 return (ENOTDIR); 644 645 switch (name[0]) { 646 case UDPCTL_CHECKSUM: 647 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 648 default: 649 return (ENOPROTOOPT); 650 } 651 /* NOTREACHED */ 652 } 653
Indexes created Fri Sep 26 20:09:58 GMT 2025