udp_usrreq.c revision 1.35
1 /* $NetBSD: udp_usrreq.c,v 1.35 1996/09/15 18:11:11 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, 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_pcblookup_connect(&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_bind(&udbtable, ip->ip_dst, uh->uh_dport); 274 if (inp == 0) { 275 udpstat.udps_noport++; 276 if (m->m_flags & (M_BCAST | M_MCAST)) { 277 udpstat.udps_noportbcast++; 278 goto bad; 279 } 280 *ip = save_ip; 281 ip->ip_len += iphlen; 282 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 283 return; 284 } 285 } 286 287 /* 288 * Construct sockaddr format source address. 289 * Stuff source address and datagram in user buffer. 290 */ 291 udpsrc.sin_family = AF_INET; 292 udpsrc.sin_len = sizeof(struct sockaddr_in); 293 udpsrc.sin_port = uh->uh_sport; 294 udpsrc.sin_addr = ip->ip_src; 295 296 if (inp->inp_flags & INP_CONTROLOPTS) { 297 struct mbuf **mp = &opts; 298 299 if (inp->inp_flags & INP_RECVDSTADDR) { 300 *mp = udp_saveopt((caddr_t) &ip->ip_dst, 301 sizeof(struct in_addr), IP_RECVDSTADDR); 302 if (*mp) 303 mp = &(*mp)->m_next; 304 } 305 #ifdef notyet 306 /* options were tossed above */ 307 if (inp->inp_flags & INP_RECVOPTS) { 308 *mp = udp_saveopt((caddr_t) opts_deleted_above, 309 sizeof(struct in_addr), IP_RECVOPTS); 310 if (*mp) 311 mp = &(*mp)->m_next; 312 } 313 /* ip_srcroute doesn't do what we want here, need to fix */ 314 if (inp->inp_flags & INP_RECVRETOPTS) { 315 *mp = udp_saveopt((caddr_t) ip_srcroute(), 316 sizeof(struct in_addr), IP_RECVRETOPTS); 317 if (*mp) 318 mp = &(*mp)->m_next; 319 } 320 #endif 321 } 322 iphlen += sizeof(struct udphdr); 323 m->m_len -= iphlen; 324 m->m_pkthdr.len -= iphlen; 325 m->m_data += iphlen; 326 if (sbappendaddr(&inp->inp_socket->so_rcv, sintosa(&udpsrc), m, 327 opts) == 0) { 328 udpstat.udps_fullsock++; 329 goto bad; 330 } 331 sorwakeup(inp->inp_socket); 332 return; 333 bad: 334 m_freem(m); 335 if (opts) 336 m_freem(opts); 337 } 338 339 /* 340 * Create a "control" mbuf containing the specified data 341 * with the specified type for presentation with a datagram. 342 */ 343 struct mbuf * 344 udp_saveopt(p, size, type) 345 caddr_t p; 346 register int size; 347 int type; 348 { 349 register struct cmsghdr *cp; 350 struct mbuf *m; 351 352 if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) 353 return ((struct mbuf *) NULL); 354 cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); 355 bcopy(p, CMSG_DATA(cp), size); 356 size += sizeof(*cp); 357 m->m_len = size; 358 cp->cmsg_len = size; 359 cp->cmsg_level = IPPROTO_IP; 360 cp->cmsg_type = type; 361 return (m); 362 } 363 364 /* 365 * Notify a udp user of an asynchronous error; 366 * just wake up so that he can collect error status. 367 */ 368 static void 369 udp_notify(inp, errno) 370 register struct inpcb *inp; 371 int errno; 372 { 373 374 inp->inp_socket->so_error = errno; 375 sorwakeup(inp->inp_socket); 376 sowwakeup(inp->inp_socket); 377 } 378 379 void * 380 udp_ctlinput(cmd, sa, v) 381 int cmd; 382 struct sockaddr *sa; 383 void *v; 384 { 385 register struct ip *ip = v; 386 register struct udphdr *uh; 387 extern int inetctlerrmap[]; 388 void (*notify) __P((struct inpcb *, int)) = udp_notify; 389 int errno; 390 391 if ((unsigned)cmd >= PRC_NCMDS) 392 return NULL; 393 errno = inetctlerrmap[cmd]; 394 if (PRC_IS_REDIRECT(cmd)) 395 notify = in_rtchange, ip = 0; 396 else if (cmd == PRC_HOSTDEAD) 397 ip = 0; 398 else if (errno == 0) 399 return NULL; 400 if (ip) { 401 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 402 in_pcbnotify(&udbtable, satosin(sa)->sin_addr, uh->uh_dport, 403 ip->ip_src, uh->uh_sport, errno, notify); 404 } else 405 in_pcbnotifyall(&udbtable, satosin(sa)->sin_addr, errno, 406 notify); 407 return NULL; 408 } 409 410 int 411 #if __STDC__ 412 udp_output(struct mbuf *m, ...) 413 #else 414 udp_output(m, va_alist) 415 struct mbuf *m; 416 va_dcl 417 #endif 418 { 419 register struct inpcb *inp; 420 register struct udpiphdr *ui; 421 register int len = m->m_pkthdr.len; 422 int error = 0; 423 va_list ap; 424 425 va_start(ap, m); 426 inp = va_arg(ap, struct inpcb *); 427 va_end(ap); 428 429 /* 430 * Calculate data length and get a mbuf 431 * for UDP and IP headers. 432 */ 433 M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT); 434 if (m == 0) { 435 error = ENOBUFS; 436 goto release; 437 } 438 439 /* 440 * Fill in mbuf with extended UDP header 441 * and addresses and length put into network format. 442 */ 443 ui = mtod(m, struct udpiphdr *); 444 bzero(ui->ui_x1, sizeof ui->ui_x1); 445 ui->ui_pr = IPPROTO_UDP; 446 ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr)); 447 ui->ui_src = inp->inp_laddr; 448 ui->ui_dst = inp->inp_faddr; 449 ui->ui_sport = inp->inp_lport; 450 ui->ui_dport = inp->inp_fport; 451 ui->ui_ulen = ui->ui_len; 452 453 /* 454 * Stuff checksum and output datagram. 455 */ 456 ui->ui_sum = 0; 457 if (udpcksum) { 458 if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0) 459 ui->ui_sum = 0xffff; 460 } 461 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 462 ((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */ 463 ((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */ 464 udpstat.udps_opackets++; 465 return (ip_output(m, inp->inp_options, &inp->inp_route, 466 inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST), 467 inp->inp_moptions)); 468 469 release: 470 m_freem(m); 471 return (error); 472 } 473 474 u_long udp_sendspace = 9216; /* really max datagram size */ 475 u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in)); 476 /* 40 1K datagrams */ 477 478 /*ARGSUSED*/ 479 int 480 udp_usrreq(so, req, m, nam, control, p) 481 struct socket *so; 482 int req; 483 struct mbuf *m, *nam, *control; 484 struct proc *p; 485 { 486 register struct inpcb *inp; 487 int s; 488 register int error = 0; 489 490 if (req == PRU_CONTROL) 491 return (in_control(so, (long)m, (caddr_t)nam, 492 (struct ifnet *)control, p)); 493 494 s = splsoftnet(); 495 inp = sotoinpcb(so); 496 #ifdef DIAGNOSTIC 497 if (req != PRU_SEND && req != PRU_SENDOOB && control) 498 panic("udp_usrreq: unexpected control mbuf"); 499 #endif 500 if (inp == 0 && req != PRU_ATTACH) { 501 error = EINVAL; 502 goto release; 503 } 504 505 /* 506 * Note: need to block udp_input while changing 507 * the udp pcb queue and/or pcb addresses. 508 */ 509 switch (req) { 510 511 case PRU_ATTACH: 512 if (inp != 0) { 513 error = EISCONN; 514 break; 515 } 516 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) { 517 error = soreserve(so, udp_sendspace, udp_recvspace); 518 if (error) 519 break; 520 } 521 error = in_pcballoc(so, &udbtable); 522 if (error) 523 break; 524 inp = sotoinpcb(so); 525 inp->inp_ip.ip_ttl = ip_defttl; 526 break; 527 528 case PRU_DETACH: 529 in_pcbdetach(inp); 530 break; 531 532 case PRU_BIND: 533 error = in_pcbbind(inp, nam, p); 534 break; 535 536 case PRU_LISTEN: 537 error = EOPNOTSUPP; 538 break; 539 540 case PRU_CONNECT: 541 error = in_pcbconnect(inp, nam); 542 if (error) 543 break; 544 soisconnected(so); 545 break; 546 547 case PRU_CONNECT2: 548 error = EOPNOTSUPP; 549 break; 550 551 case PRU_DISCONNECT: 552 /*soisdisconnected(so);*/ 553 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 554 in_pcbdisconnect(inp); 555 inp->inp_laddr = zeroin_addr; /* XXX */ 556 in_pcbstate(inp, INP_BOUND); /* 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; /* XXX */ 576 577 if (nam) { 578 laddr = inp->inp_laddr; /* XXX */ 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; /* XXX */ 599 in_pcbstate(inp, INP_BOUND); /* XXX */ 600 } 601 } 602 break; 603 604 case PRU_SENSE: 605 /* 606 * stat: don't bother with a blocksize. 607 */ 608 splx(s); 609 return (0); 610 611 case PRU_RCVOOB: 612 error = EOPNOTSUPP; 613 break; 614 615 case PRU_SENDOOB: 616 m_freem(control); 617 m_freem(m); 618 error = EOPNOTSUPP; 619 break; 620 621 case PRU_SOCKADDR: 622 in_setsockaddr(inp, nam); 623 break; 624 625 case PRU_PEERADDR: 626 in_setpeeraddr(inp, nam); 627 break; 628 629 default: 630 panic("udp_usrreq"); 631 } 632 633 release: 634 splx(s); 635 return (error); 636 } 637 638 /* 639 * Sysctl for udp variables. 640 */ 641 int 642 udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 643 int *name; 644 u_int namelen; 645 void *oldp; 646 size_t *oldlenp; 647 void *newp; 648 size_t newlen; 649 { 650 /* All sysctl names at this level are terminal. */ 651 if (namelen != 1) 652 return (ENOTDIR); 653 654 switch (name[0]) { 655 case UDPCTL_CHECKSUM: 656 return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum)); 657 default: 658 return (ENOPROTOOPT); 659 } 660 /* NOTREACHED */ 661 } 662
Indexes created Tue Sep 23 14:10:03 GMT 2025