sys/netinet/ip_demux.c

   1 /*
   2  * Copyright (c) 2003, 2004 Jeffrey M. Hsu.  All rights reserved.
   3  * Copyright (c) 2003, 2004 The DragonFly Project.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to The DragonFly Project
   6  * by Jeffrey M. Hsu.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of The DragonFly Project nor the names of its
  17  *    contributors may be used to endorse or promote products derived
  18  *    from this software without specific, prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  30  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $DragonFly: src/sys/netinet/ip_demux.c,v 1.45 2008/11/11 10:46:58 sephe Exp $
  34  */
  35
  36 #include "opt_inet.h"
  37 #include "opt_rss.h"
  38
  39 #include <sys/param.h>
  40 #include <sys/systm.h>
  41 #include <sys/kernel.h>
  42 #include <sys/socket.h>
  43 #include <sys/socketvar.h>
  44 #include <sys/thread.h>
  45 #include <sys/sysctl.h>
  46 #include <sys/globaldata.h>
  47
  48 #include <net/if.h>
  49 #include <net/netisr.h>
  50 #include <net/toeplitz2.h>
  51
  52 #include <netinet/in_systm.h>
  53 #include <netinet/in.h>
  54 #include <netinet/in_var.h>
  55 #include <netinet/in_pcb.h>
  56 #include <netinet/ip.h>
  57 #include <netinet/ip_var.h>
  58 #include <netinet/tcp.h>
  59 #include <netinet/tcpip.h>
  60 #include <netinet/tcp_var.h>
  61 #include <netinet/udp.h>
  62 #include <netinet/udp_var.h>
  63
  64 extern int udp_mpsafe_thread;
  65
  66 /*
  67  * Toeplitz hash functions - the idea is to match the hardware.
  68  */
  69 static __inline int
  70 INP_MPORT_HASH_UDP(in_addr_t faddr, in_addr_t laddr,
  71                    in_port_t fport, in_port_t lport)
  72 {
  73         return toeplitz_hash(toeplitz_rawhash_addr(faddr, laddr));
  74 }
  75
  76 static __inline int
  77 INP_MPORT_HASH_TCP(in_addr_t faddr, in_addr_t laddr,
  78                    in_port_t fport, in_port_t lport)
  79 {
  80         return toeplitz_hash(
  81                toeplitz_rawhash_addrport(faddr, laddr, fport, lport));
  82 }
  83
  84 /*
  85  * Map a network address to a processor.
  86  */
  87 int
  88 tcp_addrcpu(in_addr_t faddr, in_port_t fport, in_addr_t laddr, in_port_t lport)
  89 {
  90         return (INP_MPORT_HASH_TCP(faddr, laddr, fport, lport));
  91 }
  92
  93 /*
  94  * Not implemented yet, use protocol thread 0
  95  */
  96 int
  97 udp_addrcpu(in_addr_t faddr, in_port_t fport, in_addr_t laddr, in_port_t lport)
  98 {
  99 #ifdef notyet
 100         return (INP_MPORT_HASH_UDP(faddr, laddr, fport, lport));
 101 #else
 102         return 0;
 103 #endif
 104 }
 105
 106 /*
 107  * If the packet is a valid IP datagram, upon returning of this function
 108  * following things are promised:
 109  *
 110  * o  IP header (including any possible IP options) and any data preceding
 111  *    IP header (usually linker layer header) are in one mbuf (m_len).
 112  * o  IP header length is not less than the minimum (sizeof(struct ip)).
 113  * o  IP total length is not less than IP header length.
 114  * o  IP datagram resides completely in the mbuf chain,
 115  *    i.e. pkthdr.len >= IP total length.
 116  *
 117  * If the packet is a UDP datagram,
 118  * o  IP header (including any possible IP options) and UDP header are in
 119  *    one mbuf (m_len).
 120  * o  IP total length is not less than (IP header length + UDP header length).
 121  *
 122  * If the packet is a TCP segment,
 123  * o  IP header (including any possible IP options) and TCP header (including
 124  *    any possible TCP options) are in one mbuf (m_len).
 125  * o  TCP header length is not less than the minimum (sizeof(struct tcphdr)).
 126  * o  IP total length is not less than (IP header length + TCP header length).
 127  */
 128 boolean_t
 129 ip_lengthcheck(struct mbuf **mp, int hoff)
 130 {
 131         struct mbuf *m = *mp;
 132         struct ip *ip;
 133         int len, iphlen, iplen;
 134         struct tcphdr *th;
 135         int thoff;                              /* TCP data offset */
 136
 137         len = hoff + sizeof(struct ip);
 138
 139         /* The packet must be at least the size of an IP header. */
 140         if (m->m_pkthdr.len < len) {
 141                 ipstat.ips_tooshort++;
 142                 goto fail;
 143         }
 144
 145         /* The fixed IP header must reside completely in the first mbuf. */
 146         if (m->m_len < len) {
 147                 m = m_pullup(m, len);
 148                 if (m == NULL) {
 149                         ipstat.ips_toosmall++;
 150                         goto fail;
 151                 }
 152         }
 153
 154         ip = mtodoff(m, struct ip *, hoff);
 155
 156         /* Bound check the packet's stated IP header length. */
 157         iphlen = ip->ip_hl << 2;
 158         if (iphlen < sizeof(struct ip)) {       /* minimum header length */
 159                 ipstat.ips_badhlen++;
 160                 goto fail;
 161         }
 162
 163         /* The full IP header must reside completely in the one mbuf. */
 164         if (m->m_len < hoff + iphlen) {
 165                 m = m_pullup(m, hoff + iphlen);
 166                 if (m == NULL) {
 167                         ipstat.ips_badhlen++;
 168                         goto fail;
 169                 }
 170                 ip = mtodoff(m, struct ip *, hoff);
 171         }
 172
 173         iplen = ntohs(ip->ip_len);
 174
 175         /*
 176          * Check that the amount of data in the buffers is as
 177          * at least much as the IP header would have us expect.
 178          */
 179         if (m->m_pkthdr.len < hoff + iplen) {
 180                 ipstat.ips_tooshort++;
 181                 goto fail;
 182         }
 183
 184         /*
 185          * Fragments other than the first fragment don't have much
 186          * length information.
 187          */
 188         if (ntohs(ip->ip_off) & IP_OFFMASK)
 189                 goto ipcheckonly;
 190
 191         /*
 192          * The TCP/IP or UDP/IP header must be entirely contained within
 193          * the first fragment of a packet.  Packet filters will break if they
 194          * aren't.
 195          *
 196          * Since the packet will be trimmed to ip_len we must also make sure
 197          * the potentially trimmed down length is still sufficient to hold
 198          * the header(s).
 199          */
 200         switch (ip->ip_p) {
 201         case IPPROTO_TCP:
 202                 if (iplen < iphlen + sizeof(struct tcphdr)) {
 203                         ++tcpstat.tcps_rcvshort;
 204                         goto fail;
 205                 }
 206                 if (m->m_len < hoff + iphlen + sizeof(struct tcphdr)) {
 207                         m = m_pullup(m, hoff + iphlen + sizeof(struct tcphdr));
 208                         if (m == NULL) {
 209                                 tcpstat.tcps_rcvshort++;
 210                                 goto fail;
 211                         }
 212                         ip = mtodoff(m, struct ip *, hoff);
 213                 }
 214                 th = (struct tcphdr *)((caddr_t)ip + iphlen);
 215                 thoff = th->th_off << 2;
 216                 if (thoff < sizeof(struct tcphdr) ||
 217                     thoff + iphlen > ntohs(ip->ip_len)) {
 218                         tcpstat.tcps_rcvbadoff++;
 219                         goto fail;
 220                 }
 221                 if (m->m_len < hoff + iphlen + thoff) {
 222                         m = m_pullup(m, hoff + iphlen + thoff);
 223                         if (m == NULL) {
 224                                 tcpstat.tcps_rcvshort++;
 225                                 goto fail;
 226                         }
 227                 }
 228                 break;
 229         case IPPROTO_UDP:
 230                 if (iplen < iphlen + sizeof(struct udphdr)) {
 231                         ++udpstat.udps_hdrops;
 232                         goto fail;
 233                 }
 234                 if (m->m_len < hoff + iphlen + sizeof(struct udphdr)) {
 235                         m = m_pullup(m, hoff + iphlen + sizeof(struct udphdr));
 236                         if (m == NULL) {
 237                                 udpstat.udps_hdrops++;
 238                                 goto fail;
 239                         }
 240                 }
 241                 break;
 242         default:
 243 ipcheckonly:
 244                 if (iplen < iphlen) {
 245                         ++ipstat.ips_badlen;
 246                         goto fail;
 247                 }
 248                 break;
 249         }
 250
 251         m->m_flags |= M_LENCHECKED;
 252         *mp = m;
 253         return TRUE;
 254
 255 fail:
 256         if (m != NULL)
 257                 m_freem(m);
 258         *mp = NULL;
 259         return FALSE;
 260 }
 261
 262 /*
 263  * Assign a protocol processing thread to a packet.  The IP header is at
 264  * offset (hoff) in the packet (i.e. the mac header might still be intact).
 265  *
 266  * This function can blow away the mbuf if the packet is malformed.
 267  */
 268 void
 269 ip_cpufn(struct mbuf **mptr, int hoff, int dir)
 270 {
 271         struct ip *ip;
 272         int iphlen;
 273         struct tcphdr *th;
 274         struct udphdr *uh;
 275         struct mbuf *m;
 276         int thoff;                              /* TCP data offset */
 277         int cpu;
 278
 279         if (!ip_lengthcheck(mptr, hoff))
 280                 return;
 281
 282         m = *mptr;
 283         ip = mtodoff(m, struct ip *, hoff);
 284         iphlen = ip->ip_hl << 2;
 285
 286         /*
 287          * XXX generic packet handling defrag on CPU 0 for now.
 288          */
 289         if (ntohs(ip->ip_off) & (IP_MF | IP_OFFMASK)) {
 290                 cpu = 0;
 291                 goto back;
 292         }
 293
 294         switch (ip->ip_p) {
 295         case IPPROTO_TCP:
 296                 th = (struct tcphdr *)((caddr_t)ip + iphlen);
 297                 thoff = th->th_off << 2;
 298                 cpu = INP_MPORT_HASH_TCP(ip->ip_src.s_addr,
 299                                          ip->ip_dst.s_addr,
 300                                          th->th_sport,
 301                                          th->th_dport);
 302                 break;
 303
 304         case IPPROTO_UDP:
 305                 uh = (struct udphdr *)((caddr_t)ip + iphlen);
 306
 307                 cpu = INP_MPORT_HASH_UDP(ip->ip_src.s_addr,
 308                                          ip->ip_dst.s_addr,
 309                                          uh->uh_sport,
 310                                          uh->uh_dport);
 311                 break;
 312
 313         default:
 314                 cpu = 0;
 315                 break;
 316         }
 317 back:
 318         m->m_flags |= M_HASH;
 319         m->m_pkthdr.hash = cpu;
 320 }
 321
 322 void
 323 ip_cpufn_in(struct mbuf **mptr, int hoff)
 324 {
 325         ip_cpufn(mptr, hoff, IP_MPORT_IN);
 326 }
 327
 328 /*
 329  * Verify and adjust the hash value of the packet.
 330  *
 331  * Unlike ip_cpufn(), the packet content is not accessed.  The packet info
 332  * (pi) and the hash of the packet (m_pkthdr.hash) is used instead.
 333  *
 334  * Caller has already made sure that m_pkthdr.hash is valid, i.e. m_flags
 335  * has M_HASH set.
 336  */
 337 void
 338 ip_hashcheck(struct mbuf *m, const struct pktinfo *pi)
 339 {
 340         KASSERT((m->m_flags & M_HASH), ("no valid packet hash\n"));
 341         KASSERT(m->m_pkthdr.hash < ncpus2,
 342                 ("invalid packet hash %#x\n", m->m_pkthdr.hash));
 343
 344         /*
 345          * XXX generic packet handling defrag on CPU 0 for now.
 346          */
 347         if (pi->pi_flags & PKTINFO_FLAG_FRAG) {
 348                 m->m_pkthdr.hash = 0;
 349                 return;
 350         }
 351
 352         switch (pi->pi_l3proto) {
 353         case IPPROTO_TCP:
 354         case IPPROTO_UDP:
 355                 break;
 356
 357         default:
 358                 /* Let software calculate the hash */
 359                 m->m_flags &= ~M_HASH;
 360                 break;
 361         }
 362 }
 363
 364 /*
 365  * This is used to map a socket to a message port for sendmsg() and friends.
 366  * It is not called for any other purpose.  In the case of TCP we just return
 367  * the port already installed in the socket.
 368  */
 369 lwkt_port_t
 370 tcp_soport(struct socket *so, struct sockaddr *nam,
 371            struct mbuf **dummy __unused)
 372 {
 373         return(so->so_port);
 374 }
 375
 376 /*
 377  * Used to route icmp messages to the proper protocol thread for ctlinput
 378  * operation.
 379  */
 380 lwkt_port_t
 381 tcp_ctlport(int cmd, struct sockaddr *sa, void *vip)
 382 {
 383         struct ip *ip = vip;
 384         struct tcphdr *th;
 385         struct in_addr faddr;
 386         int cpu;
 387
 388         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 389         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 390                 return(NULL);
 391         if (ip == NULL || PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
 392                 /*
 393                  * A new message will be allocated later to save necessary
 394                  * information and will be forwarded to all network protocol
 395                  * threads in the following way:
 396                  *
 397                  * (the the thread owns the msgport that we return here)
 398                  * netisr0 <--+
 399                  *    |       |
 400                  *    |       |
 401                  *    |       |
 402                  *    +-------+
 403                  *     sendmsg
 404                  *     [msg is kmalloc()ed]
 405                  *
 406                  *
 407                  * Later on, when the msg is received by netisr0:
 408                  *
 409                  *         forwardmsg         forwardmsg
 410                  * netisr0 ---------> netisr1 ---------> netisrN
 411                  *                                       [msg is kfree()ed]
 412                  */
 413                 return cpu0_ctlport(cmd, sa, vip);
 414         } else {
 415                 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 416                 cpu = tcp_addrcpu(faddr.s_addr, th->th_dport,
 417                                   ip->ip_src.s_addr, th->th_sport);
 418         }
 419         return(cpu_portfn(cpu));
 420 }
 421
 422 lwkt_port_t
 423 tcp_addrport(in_addr_t faddr, in_port_t fport, in_addr_t laddr, in_port_t lport)
 424 {
 425         return(cpu_portfn(tcp_addrcpu(faddr, fport, laddr, lport)));
 426 }
 427
 428 lwkt_port_t
 429 tcp_addrport0(void)
 430 {
 431         return(cpu_portfn(0));
 432 }
 433
 434 lwkt_port_t
 435 udp_addrport(in_addr_t faddr, in_port_t fport, in_addr_t laddr, in_port_t lport)
 436 {
 437         return(cpu_portfn(udp_addrcpu(faddr, fport, laddr, lport)));
 438 }
 439
 440 /*
 441  * Used to route icmp messages to the proper protocol thread for ctlinput
 442  * operation.
 443  */
 444 lwkt_port_t
 445 udp_ctlport(int cmd, struct sockaddr *sa, void *vip)
 446 {
 447         struct ip *ip = vip;
 448         struct udphdr *uh;
 449         struct in_addr faddr;
 450         int cpu;
 451
 452         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 453         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 454                 return(NULL);
 455         if (PRC_IS_REDIRECT(cmd)) {
 456                 /*
 457                  * See the comment in tcp_ctlport; the only difference
 458                  * is that message is forwarded to UDP protocol theads.
 459                  */
 460                 return cpu0_ctlport(cmd, sa, vip);
 461         } else if (ip == NULL || cmd == PRC_HOSTDEAD) {
 462                 /*
 463                  * XXX
 464                  * Once UDP inpcbs are CPU localized, we should do
 465                  * the same forwarding as PRC_IS_REDIRECT(cmd)
 466                  */
 467                 cpu = 0;
 468         } else {
 469                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 470
 471                 cpu = udp_addrcpu(faddr.s_addr, ip->ip_src.s_addr,
 472                                   uh->uh_dport, uh->uh_sport);
 473         }
 474         return (cpu_portfn(cpu));
 475 }