udp_usrreq.c revision 1.34
1 /* $NetBSD: udp_usrreq.c,v 1.34 1996/09/09 14:51:23 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 static void udp_notify __P((struct inpcb *, int)); 78 static struct mbuf *udp_saveopt __P((caddr_t, int, int)); 79 80 #ifndef UDBHASHSIZE 81 #define UDBHASHSIZE 128 82 #endif 83 int udbhashsize = UDBHASHSIZE; 84 85 void 86 udp_init() 87 { 88 89 in_pcbinit(&udbtable, udbhashsize); 90 } 91 92 void 93 #if __STDC__ 94 udp_input(struct mbuf *m, ...) 95 #else 96 udp_input(m, va_alist) 97 struct mbuf *m; 98 va_dcl 99 #endif 100 { 101 register struct ip *ip; 102 register struct udphdr *uh; 103 register struct inpcb *inp; 104 struct mbuf *opts = 0; 105 int len; 106 struct ip save_ip; 107 int iphlen; 108 va_list ap; 109 struct sockaddr_in udpsrc; 110 111 va_start(ap, m); 112 iphlen = va_arg(ap, int); 113 va_end(ap); 114 115 udpstat.udps_ipackets++; 116 117 /* 118 * Strip IP options, if any; should skip this, 119 * make available to user, and use on returned packets, 120 * but we don't yet have a way to check the checksum 121 * with options still present. 122 */ 123 if (iphlen > sizeof (struct ip)) { 124 ip_stripoptions(m, (struct mbuf *)0); 125 iphlen = sizeof(struct ip); 126 } 127 128 /* 129 * Get IP and UDP header together in first mbuf. 130 */ 131 ip = mtod(m, struct ip *); 132 if (m->m_len < iphlen + sizeof(struct udphdr)) { 133 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 134 udpstat.udps_hdrops++; 135 return; 136 } 137 ip = mtod(m, struct ip *); 138 } 139 uh = (struct udphdr *)((caddr_t)ip + iphlen); 140 141 /* 142 * Make mbuf data length reflect UDP length. 143 * If not enough data to reflect UDP length, drop. 144 */ 145 len = ntohs((u_int16_t)uh->uh_ulen); 146 if (ip->ip_len != len) { 147 if (len > ip->ip_len) { 148 udpstat.udps_badlen++; 149 goto bad; 150 } 151 m_adj(m, len - ip->ip_len); 152 /* ip->ip_len = len; */ 153 } 154 /* 155 * Save a copy of the IP header in case we want restore it 156 * for sending an ICMP error message in response. 157 */ 158 save_ip = *ip; 159 160 /* 161 * Checksum extended UDP header and data. 162 */ 163 if (uh->uh_sum) { 164 bzero(((struct ipovly *)ip)->ih_x1, 165 sizeof ((struct ipovly *)ip)->ih_x1); 166 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 167 if ((uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) != 0) { 168 udpstat.udps_badsum++; 169 m_freem(m); 170 return; 171 } 172 } 173 174 if (IN_MULTICAST(ip->ip_dst.s_addr) || 175 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 176 struct socket *last; 177 /* 178 * Deliver a multicast or broadcast datagram to *all* sockets 179 * for which the local and remote addresses and ports match 180 * those of the incoming datagram. This allows more than 181 * one process to receive multi/broadcasts on the same port. 182 * (This really ought to be done for unicast datagrams as 183 * well, but that would cause problems with existing 184 * applications that open both address-specific sockets and 185 * a wildcard socket listening to the same port -- they would 186 * end up receiving duplicates of every unicast datagram. 187 * Those applications open the multiple sockets to overcome an 188 * inadequacy of the UDP socket interface, but for backwards 189 * compatibility we avoid the problem here rather than 190 * fixing the interface. Maybe 4.5BSD will remedy this?) 191 */ 192 193 /* 194 * Construct sockaddr format source address. 195 */ 196 udpsrc.sin_family = AF_INET; 197 udpsrc.sin_len = sizeof(struct sockaddr_in); 198 udpsrc.sin_port = uh->uh_sport; 199 udpsrc.sin_addr = ip->ip_src; 200 201 m->m_len -= sizeof (struct udpiphdr); 202 m->m_data += sizeof (struct udpiphdr); 203 /* 204 * Locate pcb(s) for datagram. 205 * (Algorithm copied from raw_intr().) 206 */ 207 last = NULL; 208 for (inp = udbtable.inpt_queue.cqh_first; 209 inp != (struct inpcb *)&udbtable.inpt_queue; 210 inp = inp->inp_queue.cqe_next) { 211 if (inp->inp_lport != uh->uh_dport) 212 continue; 213 if (!in_nullhost(inp->inp_laddr)) { 214 if (!in_hosteq(inp->inp_laddr, ip->ip_dst)) 215 continue; 216 } 217 if (!in_nullhost(inp->inp_faddr)) { 218 if (!in_hosteq(inp->inp_faddr, ip->ip_src) || 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(&udpsrc), 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(&udpsrc), 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 udpsrc.sin_family = AF_INET; 293 udpsrc.sin_len = sizeof(struct sockaddr_in); 294 udpsrc.sin_port = uh->uh_sport; 295 udpsrc.sin_addr = ip->ip_src; 296 297 if (inp->inp_flags & INP_CONTROLOPTS) { 298 struct mbuf **mp = &opts; 299 300 if (inp->inp_flags & INP_RECVDSTADDR) { 301 *mp = udp_saveopt((caddr_t) &ip->ip_dst, 302 sizeof(struct in_addr), IP_RECVDSTADDR); 303 if (*mp) 304 mp = &(*mp)->m_next; 305 } 306 #ifdef notyet 307 /* options were tossed above */ 308 if (inp->inp_flags & INP_RECVOPTS) { 309 *mp = udp_saveopt((caddr_t) opts_deleted_above, 310 sizeof(struct in_addr), IP_RECVOPTS); 311 if (*mp) 312 mp = &(*mp)->m_next; 313 } 314 /* ip_srcroute doesn't do what we want here, need to fix */ 315 if (inp->inp_flags & INP_RECVRETOPTS) { 316 *mp = udp_saveopt((caddr_t) ip_srcroute(), 317 sizeof(struct in_addr), IP_RECVRETOPTS); 318 if (*mp) 319 mp = &(*mp)->m_next; 320 } 321 #endif 322 } 323 iphlen += sizeof(struct udphdr); 324 m->m_len -= iphlen; 325 m->m_pkthdr.len -= iphlen; 326 m->m_data += iphlen; 327 if (sbappendaddr(&inp->inp_socket->so_rcv, sintosa(&udpsrc), m, 328 opts) == 0) { 329 udpstat.udps_fullsock++; 330 goto bad; 331 } 332 sorwakeup(inp->inp_socket); 333 return; 334 bad: 335 m_freem(m); 336 if (opts) 337 m_freem(opts); 338 } 339 340 /* 341 * Create a "control" mbuf containing the specified data 342 * with the specified type for presentation with a datagram. 343 */ 344 struct mbuf * 345 udp_saveopt(p, size, type) 346 caddr_t p; 347 register int size; 348 int type; 349 { 350 register struct cmsghdr *cp; 351 struct mbuf *m; 352 353 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 354 return ((struct mbuf *) NULL); 355 cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); 356 bcopy(p, CMSG_DATA(cp), size); 357 size += sizeof(*cp); 358 m->m_len = size; 359 cp->cmsg_len = size; 360 cp->cmsg_level = IPPROTO_IP; 361 cp->cmsg_type = type; 362 return (m); 363 } 364 365 /* 366 * Notify a udp user of an asynchronous error; 367 * just wake up so that he can collect error status. 368 */ 369 static void 370 udp_notify(inp, errno) 371 register struct inpcb *inp; 372 int errno; 373 { 374 375 inp->inp_socket->so_error = errno; 376 sorwakeup(inp->inp_socket); 377 sowwakeup(inp->inp_socket); 378 } 379 380 void * 381 udp_ctlinput(cmd, sa, v) 382 int cmd; 383 struct sockaddr *sa; 384 void *v; 385 { 386 register struct ip *ip = v; 387 register struct udphdr *uh; 388 extern int inetctlerrmap[]; 389 void (*notify) __P((struct inpcb *, int)) = udp_notify; 390 int errno; 391 392 if ((unsigned)cmd >= PRC_NCMDS) 393 return NULL; 394 errno = inetctlerrmap[cmd]; 395 if (PRC_IS_REDIRECT(cmd)) 396 notify = in_rtchange, ip = 0; 397 else if (cmd == PRC_HOSTDEAD) 398 ip = 0; 399 else if (errno == 0) 400 return NULL; 401 if (ip) { 402 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 403 in_pcbnotify(&udbtable, satosin(sa)->sin_addr, uh->uh_dport, 404 ip->ip_src, uh->uh_sport, errno, notify); 405 } else 406 in_pcbnotifyall(&udbtable, satosin(sa)->sin_addr, errno, 407 notify); 408 return NULL; 409 } 410 411 int 412 #if __STDC__ 413 udp_output(struct mbuf *m, ...) 414 #else 415 udp_output(m, va_alist) 416 struct mbuf *m; 417 va_dcl 418 #endif 419 { 420 register struct inpcb *inp; 421 register struct udpiphdr *ui; 422 register int len = m->m_pkthdr.len; 423 int error = 0; 424 va_list ap; 425 426 va_start(ap, m); 427 inp = va_arg(ap, struct inpcb *); 428 va_end(ap); 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 #ifdef DIAGNOSTIC 498 if (req != PRU_SEND && req != PRU_SENDOOB && control) 499 panic("udp_usrreq: unexpected control mbuf"); 500 #endif 501 if (inp == 0 && req != PRU_ATTACH) { 502 error = EINVAL; 503 goto release; 504 } 505 506 /* 507 * Note: need to block udp_input while changing 508 * the udp pcb queue and/or pcb addresses. 509 */ 510 switch (req) { 511 512 case PRU_ATTACH: 513 if (inp != 0) { 514 error = EISCONN; 515 break; 516 } 517 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 518 error = soreserve(so, udp_sendspace, udp_recvspace); 519 if (error) 520 break; 521 } 522 error = in_pcballoc(so, &udbtable); 523 if (error) 524 break; 525 inp = sotoinpcb(so); 526 inp->inp_ip.ip_ttl = ip_defttl; 527 break; 528 529 case PRU_DETACH: 530 in_pcbdetach(inp); 531 break; 532 533 case PRU_BIND: 534 error = in_pcbbind(inp, nam, p); 535 break; 536 537 case PRU_LISTEN: 538 error = EOPNOTSUPP; 539 break; 540 541 case PRU_CONNECT: 542 error = in_pcbconnect(inp, nam); 543 if (error) 544 break; 545 soisconnected(so); 546 break; 547 548 case PRU_CONNECT2: 549 error = EOPNOTSUPP; 550 break; 551 552 case PRU_DISCONNECT: 553 /*soisdisconnected(so);*/ 554 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 555 in_pcbdisconnect(inp); 556 inp->inp_laddr = zeroin_addr; /* XXX */ 557 break; 558 559 case PRU_SHUTDOWN: 560 socantsendmore(so); 561 break; 562 563 case PRU_RCVD: 564 error = EOPNOTSUPP; 565 break; 566 567 case PRU_SEND: 568 if (control && control->m_len) { 569 m_freem(control); 570 m_freem(m); 571 error = EINVAL; 572 break; 573 } 574 { 575 struct in_addr laddr; 576 577 if (nam) { 578 laddr = inp->inp_laddr; 579 if ((so->so_state & SS_ISCONNECTED) != 0) { 580 error = EISCONN; 581 goto die; 582 } 583 error = in_pcbconnect(inp, nam); 584 if (error) { 585 die: 586 m_freem(m); 587 break; 588 } 589 } else { 590 if ((so->so_state & SS_ISCONNECTED) == 0) { 591 error = ENOTCONN; 592 goto die; 593 } 594 } 595 error = udp_output(m, inp); 596 if (nam) { 597 in_pcbdisconnect(inp); 598 inp->inp_laddr = laddr; 599 } 600 } 601 break; 602 603 case PRU_SENSE: 604 /* 605 * stat: don't bother with a blocksize. 606 */ 607 splx(s); 608 return (0); 609 610 case PRU_RCVOOB: 611 error = EOPNOTSUPP; 612 break; 613 614 case PRU_SENDOOB: 615 m_freem(control); 616 m_freem(m); 617 error = EOPNOTSUPP; 618 break; 619 620 case PRU_SOCKADDR: 621 in_setsockaddr(inp, nam); 622 break; 623 624 case PRU_PEERADDR: 625 in_setpeeraddr(inp, nam); 626 break; 627 628 default: 629 panic("udp_usrreq"); 630 } 631 632 release: 633 splx(s); 634 return (error); 635 } 636 637 /* 638 * Sysctl for udp variables. 639 */ 640 int 641 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 642 int *name; 643 u_int namelen; 644 void *oldp; 645 size_t *oldlenp; 646 void *newp; 647 size_t newlen; 648 { 649 /* All sysctl names at this level are terminal. */ 650 if (namelen != 1) 651 return (ENOTDIR); 652 653 switch (name[0]) { 654 case UDPCTL_CHECKSUM: 655 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 656 default: 657 return (ENOPROTOOPT); 658 } 659 /* NOTREACHED */ 660 } 661
Indexes created Sun Sep 21 14:09:52 GMT 2025