| 1 | /* |
| 2 | * Copyright (c) 1982, 1986, 1988, 1990 Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. All advertising materials mentioning features or use of this software |
| 14 | * must display the following acknowledgement: |
| 15 | * This product includes software developed by the University of |
| 16 | * California, Berkeley and its contributors. |
| 17 | * 4. Neither the name of the University nor the names of its contributors |
| 18 | * may be used to endorse or promote products derived from this software |
| 19 | * without specific prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 | * SUCH DAMAGE. |
| 32 | * |
| 33 | * @(#)udp_usrreq.c 7.20 (Berkeley) 4/20/91 |
| 34 | */ |
| 35 | |
| 36 | #include "param.h" |
| 37 | #include "malloc.h" |
| 38 | #include "mbuf.h" |
| 39 | #include "protosw.h" |
| 40 | #include "socket.h" |
| 41 | #include "socketvar.h" |
| 42 | #include "stat.h" |
| 43 | |
| 44 | #include "../net/if.h" |
| 45 | #include "../net/route.h" |
| 46 | |
| 47 | #include "in.h" |
| 48 | #include "in_systm.h" |
| 49 | #include "ip.h" |
| 50 | #include "in_pcb.h" |
| 51 | #include "ip_var.h" |
| 52 | #include "ip_icmp.h" |
| 53 | #include "udp.h" |
| 54 | #include "udp_var.h" |
| 55 | |
| 56 | struct inpcb *udp_last_inpcb = &udb; |
| 57 | |
| 58 | /* |
| 59 | * UDP protocol implementation. |
| 60 | * Per RFC 768, August, 1980. |
| 61 | */ |
| 62 | udp_init() |
| 63 | { |
| 64 | |
| 65 | udb.inp_next = udb.inp_prev = &udb; |
| 66 | } |
| 67 | |
| 68 | #ifndef COMPAT_42 |
| 69 | int udpcksum = 1; |
| 70 | #else |
| 71 | int udpcksum = 0; /* XXX */ |
| 72 | #endif |
| 73 | int udp_ttl = UDP_TTL; |
| 74 | |
| 75 | struct sockaddr_in udp_in = { sizeof(udp_in), AF_INET }; |
| 76 | |
| 77 | udp_input(m, iphlen) |
| 78 | register struct mbuf *m; |
| 79 | int iphlen; |
| 80 | { |
| 81 | register struct ip *ip; |
| 82 | register struct udphdr *uh; |
| 83 | register struct inpcb *inp; |
| 84 | struct mbuf *opts = 0; |
| 85 | int len; |
| 86 | struct ip save_ip; |
| 87 | |
| 88 | udpstat.udps_ipackets++; |
| 89 | |
| 90 | /* |
| 91 | * Strip IP options, if any; should skip this, |
| 92 | * make available to user, and use on returned packets, |
| 93 | * but we don't yet have a way to check the checksum |
| 94 | * with options still present. |
| 95 | */ |
| 96 | if (iphlen > sizeof (struct ip)) { |
| 97 | ip_stripoptions(m, (struct mbuf *)0); |
| 98 | iphlen = sizeof(struct ip); |
| 99 | } |
| 100 | |
| 101 | /* |
| 102 | * Get IP and UDP header together in first mbuf. |
| 103 | */ |
| 104 | ip = mtod(m, struct ip *); |
| 105 | if (m->m_len < iphlen + sizeof(struct udphdr)) { |
| 106 | if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { |
| 107 | udpstat.udps_hdrops++; |
| 108 | return; |
| 109 | } |
| 110 | ip = mtod(m, struct ip *); |
| 111 | } |
| 112 | uh = (struct udphdr *)((caddr_t)ip + iphlen); |
| 113 | |
| 114 | /* |
| 115 | * Make mbuf data length reflect UDP length. |
| 116 | * If not enough data to reflect UDP length, drop. |
| 117 | */ |
| 118 | len = ntohs((u_short)uh->uh_ulen); |
| 119 | if (ip->ip_len != len) { |
| 120 | if (len > ip->ip_len) { |
| 121 | udpstat.udps_badlen++; |
| 122 | goto bad; |
| 123 | } |
| 124 | m_adj(m, len - ip->ip_len); |
| 125 | /* ip->ip_len = len; */ |
| 126 | } |
| 127 | /* |
| 128 | * Save a copy of the IP header in case we want restore it |
| 129 | * for sending an ICMP error message in response. |
| 130 | */ |
| 131 | save_ip = *ip; |
| 132 | |
| 133 | /* |
| 134 | * Checksum extended UDP header and data. |
| 135 | */ |
| 136 | if (udpcksum && uh->uh_sum) { |
| 137 | ((struct ipovly *)ip)->ih_next = 0; |
| 138 | ((struct ipovly *)ip)->ih_prev = 0; |
| 139 | ((struct ipovly *)ip)->ih_x1 = 0; |
| 140 | ((struct ipovly *)ip)->ih_len = uh->uh_ulen; |
| 141 | if (uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) { |
| 142 | udpstat.udps_badsum++; |
| 143 | m_freem(m); |
| 144 | return; |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | /* |
| 149 | * Locate pcb for datagram. |
| 150 | */ |
| 151 | inp = udp_last_inpcb; |
| 152 | if (inp->inp_lport != uh->uh_dport || |
| 153 | inp->inp_fport != uh->uh_sport || |
| 154 | inp->inp_faddr.s_addr != ip->ip_src.s_addr || |
| 155 | inp->inp_laddr.s_addr != ip->ip_dst.s_addr) { |
| 156 | inp = in_pcblookup(&udb, ip->ip_src, uh->uh_sport, |
| 157 | ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD); |
| 158 | if (inp) |
| 159 | udp_last_inpcb = inp; |
| 160 | udpstat.udpps_pcbcachemiss++; |
| 161 | } |
| 162 | if (inp == 0) { |
| 163 | /* don't send ICMP response for broadcast packet */ |
| 164 | udpstat.udps_noport++; |
| 165 | if (m->m_flags & M_BCAST) { |
| 166 | udpstat.udps_noportbcast++; |
| 167 | goto bad; |
| 168 | } |
| 169 | *ip = save_ip; |
| 170 | ip->ip_len += iphlen; |
| 171 | icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT); |
| 172 | return; |
| 173 | } |
| 174 | |
| 175 | /* |
| 176 | * Construct sockaddr format source address. |
| 177 | * Stuff source address and datagram in user buffer. |
| 178 | */ |
| 179 | udp_in.sin_port = uh->uh_sport; |
| 180 | udp_in.sin_addr = ip->ip_src; |
| 181 | if (inp->inp_flags & INP_CONTROLOPTS) { |
| 182 | struct mbuf **mp = &opts; |
| 183 | struct mbuf *udp_saveopt(); |
| 184 | |
| 185 | if (inp->inp_flags & INP_RECVDSTADDR) { |
| 186 | *mp = udp_saveopt((caddr_t) &ip->ip_dst, |
| 187 | sizeof(struct in_addr), IP_RECVDSTADDR); |
| 188 | if (*mp) |
| 189 | mp = &(*mp)->m_next; |
| 190 | } |
| 191 | #ifdef notyet |
| 192 | /* options were tossed above */ |
| 193 | if (inp->inp_flags & INP_RECVOPTS) { |
| 194 | *mp = udp_saveopt((caddr_t) opts_deleted_above, |
| 195 | sizeof(struct in_addr), IP_RECVOPTS); |
| 196 | if (*mp) |
| 197 | mp = &(*mp)->m_next; |
| 198 | } |
| 199 | /* ip_srcroute doesn't do what we want here, need to fix */ |
| 200 | if (inp->inp_flags & INP_RECVRETOPTS) { |
| 201 | *mp = udp_saveopt((caddr_t) ip_srcroute(), |
| 202 | sizeof(struct in_addr), IP_RECVRETOPTS); |
| 203 | if (*mp) |
| 204 | mp = &(*mp)->m_next; |
| 205 | } |
| 206 | #endif |
| 207 | } |
| 208 | iphlen += sizeof(struct udphdr); |
| 209 | m->m_len -= iphlen; |
| 210 | m->m_pkthdr.len -= iphlen; |
| 211 | m->m_data += iphlen; |
| 212 | if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in, |
| 213 | m, opts) == 0) { |
| 214 | udpstat.udps_fullsock++; |
| 215 | goto bad; |
| 216 | } |
| 217 | sorwakeup(inp->inp_socket); |
| 218 | return; |
| 219 | bad: |
| 220 | m_freem(m); |
| 221 | if (opts) |
| 222 | m_freem(opts); |
| 223 | } |
| 224 | |
| 225 | /* |
| 226 | * Create a "control" mbuf containing the specified data |
| 227 | * with the specified type for presentation with a datagram. |
| 228 | */ |
| 229 | struct mbuf * |
| 230 | udp_saveopt(p, size, type) |
| 231 | caddr_t p; |
| 232 | register int size; |
| 233 | int type; |
| 234 | { |
| 235 | register struct cmsghdr *cp; |
| 236 | struct mbuf *m; |
| 237 | |
| 238 | if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL) |
| 239 | return ((struct mbuf *) NULL); |
| 240 | cp = (struct cmsghdr *) mtod(m, struct cmsghdr *); |
| 241 | bcopy(p, (caddr_t)(cp + 1), size); |
| 242 | size += sizeof(*cp); |
| 243 | m->m_len = size; |
| 244 | cp->cmsg_len = size; |
| 245 | cp->cmsg_level = IPPROTO_IP; |
| 246 | cp->cmsg_type = type; |
| 247 | return (m); |
| 248 | } |
| 249 | |
| 250 | /* |
| 251 | * Notify a udp user of an asynchronous error; |
| 252 | * just wake up so that he can collect error status. |
| 253 | */ |
| 254 | udp_notify(inp, errno) |
| 255 | register struct inpcb *inp; |
| 256 | { |
| 257 | |
| 258 | inp->inp_socket->so_error = errno; |
| 259 | sorwakeup(inp->inp_socket); |
| 260 | sowwakeup(inp->inp_socket); |
| 261 | } |
| 262 | |
| 263 | udp_ctlinput(cmd, sa, ip) |
| 264 | int cmd; |
| 265 | struct sockaddr *sa; |
| 266 | register struct ip *ip; |
| 267 | { |
| 268 | register struct udphdr *uh; |
| 269 | extern struct in_addr zeroin_addr; |
| 270 | extern u_char inetctlerrmap[]; |
| 271 | |
| 272 | if ((unsigned)cmd > PRC_NCMDS || inetctlerrmap[cmd] == 0) |
| 273 | return; |
| 274 | if (ip) { |
| 275 | uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); |
| 276 | in_pcbnotify(&udb, sa, uh->uh_dport, ip->ip_src, uh->uh_sport, |
| 277 | cmd, udp_notify); |
| 278 | } else |
| 279 | in_pcbnotify(&udb, sa, 0, zeroin_addr, 0, cmd, udp_notify); |
| 280 | } |
| 281 | |
| 282 | udp_output(inp, m, addr, control) |
| 283 | register struct inpcb *inp; |
| 284 | register struct mbuf *m; |
| 285 | struct mbuf *addr, *control; |
| 286 | { |
| 287 | register struct udpiphdr *ui; |
| 288 | register int len = m->m_pkthdr.len; |
| 289 | struct in_addr laddr; |
| 290 | int s, error = 0; |
| 291 | |
| 292 | if (control) |
| 293 | m_freem(control); /* XXX */ |
| 294 | |
| 295 | if (addr) { |
| 296 | laddr = inp->inp_laddr; |
| 297 | if (inp->inp_faddr.s_addr != INADDR_ANY) { |
| 298 | error = EISCONN; |
| 299 | goto release; |
| 300 | } |
| 301 | /* |
| 302 | * Must block input while temporarily connected. |
| 303 | */ |
| 304 | s = splnet(); |
| 305 | error = in_pcbconnect(inp, addr); |
| 306 | if (error) { |
| 307 | splx(s); |
| 308 | goto release; |
| 309 | } |
| 310 | } else { |
| 311 | if (inp->inp_faddr.s_addr == INADDR_ANY) { |
| 312 | error = ENOTCONN; |
| 313 | goto release; |
| 314 | } |
| 315 | } |
| 316 | /* |
| 317 | * Calculate data length and get a mbuf |
| 318 | * for UDP and IP headers. |
| 319 | */ |
| 320 | M_PREPEND(m, sizeof(struct udpiphdr), M_WAIT); |
| 321 | |
| 322 | /* |
| 323 | * Fill in mbuf with extended UDP header |
| 324 | * and addresses and length put into network format. |
| 325 | */ |
| 326 | ui = mtod(m, struct udpiphdr *); |
| 327 | ui->ui_next = ui->ui_prev = 0; |
| 328 | ui->ui_x1 = 0; |
| 329 | ui->ui_pr = IPPROTO_UDP; |
| 330 | ui->ui_len = htons((u_short)len + sizeof (struct udphdr)); |
| 331 | ui->ui_src = inp->inp_laddr; |
| 332 | ui->ui_dst = inp->inp_faddr; |
| 333 | ui->ui_sport = inp->inp_lport; |
| 334 | ui->ui_dport = inp->inp_fport; |
| 335 | ui->ui_ulen = ui->ui_len; |
| 336 | |
| 337 | /* |
| 338 | * Stuff checksum and output datagram. |
| 339 | */ |
| 340 | ui->ui_sum = 0; |
| 341 | if (udpcksum) { |
| 342 | if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0) |
| 343 | ui->ui_sum = 0xffff; |
| 344 | } |
| 345 | ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; |
| 346 | ((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */ |
| 347 | ((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */ |
| 348 | udpstat.udps_opackets++; |
| 349 | error = ip_output(m, inp->inp_options, &inp->inp_route, |
| 350 | inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST)); |
| 351 | |
| 352 | if (addr) { |
| 353 | in_pcbdisconnect(inp); |
| 354 | inp->inp_laddr = laddr; |
| 355 | splx(s); |
| 356 | } |
| 357 | return (error); |
| 358 | |
| 359 | release: |
| 360 | m_freem(m); |
| 361 | return (error); |
| 362 | } |
| 363 | |
| 364 | u_long udp_sendspace = 9216; /* really max datagram size */ |
| 365 | u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in)); |
| 366 | /* 40 1K datagrams */ |
| 367 | |
| 368 | /*ARGSUSED*/ |
| 369 | udp_usrreq(so, req, m, addr, control) |
| 370 | struct socket *so; |
| 371 | int req; |
| 372 | struct mbuf *m, *addr, *control; |
| 373 | { |
| 374 | struct inpcb *inp = sotoinpcb(so); |
| 375 | int error = 0; |
| 376 | int s; |
| 377 | |
| 378 | if (req == PRU_CONTROL) |
| 379 | return (in_control(so, (int)m, (caddr_t)addr, |
| 380 | (struct ifnet *)control)); |
| 381 | if (inp == NULL && req != PRU_ATTACH) { |
| 382 | error = EINVAL; |
| 383 | goto release; |
| 384 | } |
| 385 | /* |
| 386 | * Note: need to block udp_input while changing |
| 387 | * the udp pcb queue and/or pcb addresses. |
| 388 | */ |
| 389 | switch (req) { |
| 390 | |
| 391 | case PRU_ATTACH: |
| 392 | if (inp != NULL) { |
| 393 | error = EINVAL; |
| 394 | break; |
| 395 | } |
| 396 | s = splnet(); |
| 397 | error = in_pcballoc(so, &udb); |
| 398 | splx(s); |
| 399 | if (error) |
| 400 | break; |
| 401 | error = soreserve(so, udp_sendspace, udp_recvspace); |
| 402 | if (error) |
| 403 | break; |
| 404 | ((struct inpcb *) so->so_pcb)->inp_ip.ip_ttl = udp_ttl; |
| 405 | break; |
| 406 | |
| 407 | case PRU_DETACH: |
| 408 | udp_detach(inp); |
| 409 | break; |
| 410 | |
| 411 | case PRU_BIND: |
| 412 | s = splnet(); |
| 413 | error = in_pcbbind(inp, addr); |
| 414 | splx(s); |
| 415 | break; |
| 416 | |
| 417 | case PRU_LISTEN: |
| 418 | error = EOPNOTSUPP; |
| 419 | break; |
| 420 | |
| 421 | case PRU_CONNECT: |
| 422 | if (inp->inp_faddr.s_addr != INADDR_ANY) { |
| 423 | error = EISCONN; |
| 424 | break; |
| 425 | } |
| 426 | s = splnet(); |
| 427 | error = in_pcbconnect(inp, addr); |
| 428 | splx(s); |
| 429 | if (error == 0) |
| 430 | soisconnected(so); |
| 431 | break; |
| 432 | |
| 433 | case PRU_CONNECT2: |
| 434 | error = EOPNOTSUPP; |
| 435 | break; |
| 436 | |
| 437 | case PRU_ACCEPT: |
| 438 | error = EOPNOTSUPP; |
| 439 | break; |
| 440 | |
| 441 | case PRU_DISCONNECT: |
| 442 | if (inp->inp_faddr.s_addr == INADDR_ANY) { |
| 443 | error = ENOTCONN; |
| 444 | break; |
| 445 | } |
| 446 | s = splnet(); |
| 447 | in_pcbdisconnect(inp); |
| 448 | inp->inp_laddr.s_addr = INADDR_ANY; |
| 449 | splx(s); |
| 450 | so->so_state &= ~SS_ISCONNECTED; /* XXX */ |
| 451 | break; |
| 452 | |
| 453 | case PRU_SHUTDOWN: |
| 454 | socantsendmore(so); |
| 455 | break; |
| 456 | |
| 457 | case PRU_SEND: |
| 458 | return (udp_output(inp, m, addr, control)); |
| 459 | |
| 460 | case PRU_ABORT: |
| 461 | soisdisconnected(so); |
| 462 | udp_detach(inp); |
| 463 | break; |
| 464 | |
| 465 | case PRU_SOCKADDR: |
| 466 | in_setsockaddr(inp, addr); |
| 467 | break; |
| 468 | |
| 469 | case PRU_PEERADDR: |
| 470 | in_setpeeraddr(inp, addr); |
| 471 | break; |
| 472 | |
| 473 | case PRU_SENSE: |
| 474 | /* |
| 475 | * stat: don't bother with a blocksize. |
| 476 | */ |
| 477 | return (0); |
| 478 | |
| 479 | case PRU_SENDOOB: |
| 480 | case PRU_FASTTIMO: |
| 481 | case PRU_SLOWTIMO: |
| 482 | case PRU_PROTORCV: |
| 483 | case PRU_PROTOSEND: |
| 484 | error = EOPNOTSUPP; |
| 485 | break; |
| 486 | |
| 487 | case PRU_RCVD: |
| 488 | case PRU_RCVOOB: |
| 489 | return (EOPNOTSUPP); /* do not free mbuf's */ |
| 490 | |
| 491 | default: |
| 492 | panic("udp_usrreq"); |
| 493 | } |
| 494 | |
| 495 | release: |
| 496 | if (control) { |
| 497 | printf("udp control data unexpectedly retained\n"); |
| 498 | m_freem(control); |
| 499 | } |
| 500 | if (m) |
| 501 | m_freem(m); |
| 502 | return (error); |
| 503 | } |
| 504 | |
| 505 | udp_detach(inp) |
| 506 | struct inpcb *inp; |
| 507 | { |
| 508 | int s = splnet(); |
| 509 | |
| 510 | if (inp == udp_last_inpcb) |
| 511 | udp_last_inpcb = &udb; |
| 512 | in_pcbdetach(inp); |
| 513 | splx(s); |
| 514 | } |