src/rx/rx_user.c

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   5  * This software has been released under the terms of the IBM Public
   6  * License.  For details, see the LICENSE file in the top-level source
   7  * directory or online at http://www.openafs.org/dl/license10.html
   8  */
   9
  10 /* rx_user.c contains routines specific to the user space UNIX implementation of rx */
  11
  12 /* rxi_syscall is currently not prototyped */
  13
  14 #include <afsconfig.h>
  15 #include <afs/param.h>
  16
  17 #include <roken.h>
  18
  19 #include <afs/opr.h>
  20
  21 #ifdef AFS_NT40_ENV
  22 # include <WINNT/syscfg.h>
  23 #else
  24 # include <net/if.h>
  25 #endif
  26 #if !defined(AFS_AIX_ENV) && !defined(AFS_NT40_ENV)
  27 # include <sys/syscall.h>
  28 #endif
  29 #include <afs/afs_args.h>
  30 #include <afs/afsutil.h>
  31
  32 #ifndef IPPORT_USERRESERVED
  33 /* If in.h doesn't define this, define it anyway.  Unfortunately, defining
  34    this doesn't put the code into the kernel to restrict kernel assigned
  35    port numbers to numbers below IPPORT_USERRESERVED...  */
  36 #define IPPORT_USERRESERVED 5000
  37 # endif
  38
  39 #if defined(AFS_LINUX22_ENV) && defined(AFS_RXERRQ_ENV)
  40 # include <linux/types.h>
  41 # include <linux/errqueue.h>
  42 # if defined(AFS_ADAPT_PMTU) && !defined(IP_MTU)
  43 #  define IP_MTU 14
  44 # endif
  45 #endif
  46
  47 #include "rx.h"
  48 #include "rx_atomic.h"
  49 #include "rx_globals.h"
  50 #include "rx_stats.h"
  51 #include "rx_peer.h"
  52 #include "rx_packet.h"
  53 #include "rx_internal.h"
  54
  55 #ifdef AFS_PTHREAD_ENV
  56
  57 /*
  58  * The rx_if_init_mutex mutex protects the following global variables:
  59  * Inited
  60  */
  61
  62 afs_kmutex_t rx_if_init_mutex;
  63 #define LOCK_IF_INIT MUTEX_ENTER(&rx_if_init_mutex)
  64 #define UNLOCK_IF_INIT MUTEX_EXIT(&rx_if_init_mutex)
  65
  66 /*
  67  * The rx_if_mutex mutex protects the following global variables:
  68  * myNetFlags
  69  * myNetMTUs
  70  * myNetMasks
  71  */
  72
  73 afs_kmutex_t rx_if_mutex;
  74 #define LOCK_IF MUTEX_ENTER(&rx_if_mutex)
  75 #define UNLOCK_IF MUTEX_EXIT(&rx_if_mutex)
  76 #else
  77 #define LOCK_IF_INIT
  78 #define UNLOCK_IF_INIT
  79 #define LOCK_IF
  80 #define UNLOCK_IF
  81 #endif /* AFS_PTHREAD_ENV */
  82
  83
  84 /*
  85  * Make a socket for receiving/sending IP packets.  Set it into non-blocking
  86  * and large buffering modes.  If port isn't specified, the kernel will pick
  87  * one.  Returns the socket (>= 0) on success.  Returns OSI_NULLSOCKET on
  88  * failure. Port must be in network byte order.
  89  */
  90 osi_socket
  91 rxi_GetHostUDPSocket(u_int ahost, u_short port)
  92 {
  93     int binds, code = 0;
  94     osi_socket socketFd = OSI_NULLSOCKET;
  95     struct sockaddr_in taddr;
  96     char *name = "rxi_GetUDPSocket: ";
  97 #ifdef AFS_LINUX22_ENV
  98 # if defined(AFS_ADAPT_PMTU)
  99     int pmtu = IP_PMTUDISC_WANT;
 100 # else
 101     int pmtu = IP_PMTUDISC_DONT;
 102 # endif
 103 #endif
 104
 105 #if !defined(AFS_NT40_ENV)
 106     if (ntohs(port) >= IPPORT_RESERVED && ntohs(port) < IPPORT_USERRESERVED) {
 107 /*      (osi_Msg "%s*WARNING* port number %d is not a reserved port number.  Use port numbers above %d\n", name, port, IPPORT_USERRESERVED);
 108 */ ;
 109     }
 110     if (ntohs(port) > 0 && ntohs(port) < IPPORT_RESERVED && geteuid() != 0) {
 111         (osi_Msg
 112          "%sport number %d is a reserved port number which may only be used by root.  Use port numbers above %d\n",
 113          name, ntohs(port), IPPORT_USERRESERVED);
 114         goto error;
 115     }
 116 #endif
 117     socketFd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 118
 119     if (socketFd == OSI_NULLSOCKET) {
 120 #ifdef AFS_NT40_ENV
 121         fprintf(stderr, "socket() failed with error %u\n", WSAGetLastError());
 122 #else
 123         perror("socket");
 124 #endif
 125         goto error;
 126     }
 127
 128 #ifdef AFS_NT40_ENV
 129     rxi_xmit_init(socketFd);
 130 #endif /* AFS_NT40_ENV */
 131
 132     taddr.sin_addr.s_addr = ahost;
 133     taddr.sin_family = AF_INET;
 134     taddr.sin_port = (u_short) port;
 135     memset(&taddr.sin_zero, 0, sizeof(taddr.sin_zero));
 136 #ifdef STRUCT_SOCKADDR_HAS_SA_LEN
 137     taddr.sin_len = sizeof(struct sockaddr_in);
 138 #endif
 139 #define MAX_RX_BINDS 10
 140     for (binds = 0; binds < MAX_RX_BINDS; binds++) {
 141         if (binds)
 142             rxi_Delay(10);
 143         code = bind(socketFd, (struct sockaddr *)&taddr, sizeof(taddr));
 144         break;
 145     }
 146     if (code) {
 147         (osi_Msg "%sbind failed\n", name);
 148         goto error;
 149     }
 150 #if !defined(AFS_NT40_ENV)
 151     /*
 152      * Set close-on-exec on rx socket
 153      */
 154     fcntl(socketFd, F_SETFD, 1);
 155 #endif
 156
 157     /* Use one of three different ways of getting a socket buffer expanded to
 158      * a reasonable size.
 159      */
 160     {
 161         int greedy = 0;
 162         int len1, len2;
 163
 164         len1 = 32766;
 165         len2 = rx_UdpBufSize;
 166
 167         /* find the size closest to rx_UdpBufSize that will be accepted */
 168         while (!greedy && len2 > len1) {
 169             greedy =
 170                 (setsockopt
 171                   (socketFd, SOL_SOCKET, SO_RCVBUF, (char *)&len2,
 172                    sizeof(len2)) >= 0);
 173             if (!greedy)
 174                 len2 /= 2;
 175         }
 176
 177         /* but do not let it get smaller than 32K */
 178         if (len2 < len1)
 179             len2 = len1;
 180
 181         if (len1 < len2)
 182             len1 = len2;
 183
 184
 185         greedy =
 186             (setsockopt
 187              (socketFd, SOL_SOCKET, SO_SNDBUF, (char *)&len1,
 188               sizeof(len1)) >= 0)
 189             &&
 190             (setsockopt
 191              (socketFd, SOL_SOCKET, SO_RCVBUF, (char *)&len2,
 192               sizeof(len2)) >= 0);
 193         if (!greedy)
 194             (osi_Msg "%s*WARNING* Unable to increase buffering on socket\n",
 195              name);
 196         if (rx_stats_active)
 197             rx_atomic_set(&rx_stats.socketGreedy, greedy);
 198     }
 199
 200 #ifdef AFS_LINUX22_ENV
 201     setsockopt(socketFd, SOL_IP, IP_MTU_DISCOVER, &pmtu, sizeof(pmtu));
 202 #endif
 203 #ifdef AFS_RXERRQ_ENV
 204     {
 205         int recverr = 1;
 206         setsockopt(socketFd, SOL_IP, IP_RECVERR, &recverr, sizeof(recverr));
 207     }
 208 #endif
 209     if (rxi_Listen(socketFd) < 0) {
 210         goto error;
 211     }
 212
 213     return socketFd;
 214
 215   error:
 216 #ifdef AFS_NT40_ENV
 217     if (socketFd != OSI_NULLSOCKET)
 218         closesocket(socketFd);
 219 #else
 220     if (socketFd != OSI_NULLSOCKET)
 221         close(socketFd);
 222 #endif
 223
 224     return OSI_NULLSOCKET;
 225 }
 226
 227 osi_socket
 228 rxi_GetUDPSocket(u_short port)
 229 {
 230     return rxi_GetHostUDPSocket(htonl(INADDR_ANY), port);
 231 }
 232
 233 void
 234 osi_Panic(char *msg, ...)
 235 {
 236     va_list ap;
 237     va_start(ap, msg);
 238     (osi_Msg "Fatal Rx error: ");
 239     (osi_VMsg msg, ap);
 240     va_end(ap);
 241     fflush(stderr);
 242     fflush(stdout);
 243     opr_abort();
 244 }
 245
 246 /*
 247  * osi_AssertFailU() -- used by the osi_Assert() macro.
 248  */
 249
 250 void
 251 osi_AssertFailU(const char *expr, const char *file, int line)
 252 {
 253     osi_Panic("assertion failed: %s, file: %s, line: %d\n", expr,
 254               file, line);
 255 }
 256
 257 #if defined(AFS_AIX32_ENV) && !defined(KERNEL)
 258 #ifndef osi_Alloc
 259 static const char memZero;
 260 void *
 261 osi_Alloc(afs_int32 x)
 262 {
 263     /*
 264      * 0-length allocs may return NULL ptr from malloc, so we special-case
 265      * things so that NULL returned iff an error occurred
 266      */
 267     if (x == 0)
 268         return (void *)&memZero;
 269     return(malloc(x));
 270 }
 271
 272 void
 273 osi_Free(void *x, afs_int32 size)
 274 {
 275     if (x == &memZero)
 276         return;
 277     free(x);
 278 }
 279 #endif
 280 #endif /* defined(AFS_AIX32_ENV) && !defined(KERNEL) */
 281
 282 #define ADDRSPERSITE    16
 283
 284
 285 static afs_uint32 rxi_NetAddrs[ADDRSPERSITE];   /* host order */
 286 static int myNetMTUs[ADDRSPERSITE];
 287 static int myNetMasks[ADDRSPERSITE];
 288 static int myNetFlags[ADDRSPERSITE];
 289 static u_int rxi_numNetAddrs;
 290 static int Inited = 0;
 291
 292 #if defined(AFS_NT40_ENV)
 293 int
 294 rxi_getaddr(void)
 295 {
 296     /* The IP address list can change so we must query for it */
 297     rx_GetIFInfo();
 298
 299     /* we don't want to use the loopback adapter which is first */
 300     /* this is a bad bad hack */
 301     if (rxi_numNetAddrs > 1)
 302         return htonl(rxi_NetAddrs[1]);
 303     else if (rxi_numNetAddrs > 0)
 304         return htonl(rxi_NetAddrs[0]);
 305     else
 306         return 0;
 307 }
 308
 309 /*
 310 ** return number of addresses
 311 ** and the addresses themselves in the buffer
 312 ** maxSize - max number of interfaces to return.
 313 */
 314 int
 315 rx_getAllAddr(afs_uint32 * buffer, int maxSize)
 316 {
 317     int count = 0, offset = 0;
 318
 319     /* The IP address list can change so we must query for it */
 320     rx_GetIFInfo();
 321
 322     for (count = 0; offset < rxi_numNetAddrs && maxSize > 0;
 323          count++, offset++, maxSize--)
 324         buffer[count] = htonl(rxi_NetAddrs[offset]);
 325
 326     return count;
 327 }
 328
 329 /* this function returns the total number of interface addresses
 330  * the buffer has to be passed in by the caller. It also returns
 331  * the matching interface mask and mtu.  All values are returned
 332  * in network byte order.
 333  */
 334 int
 335 rx_getAllAddrMaskMtu(afs_uint32 addrBuffer[], afs_uint32 maskBuffer[],
 336                      afs_uint32 mtuBuffer[], int maxSize)
 337 {
 338     int count = 0, offset = 0;
 339
 340     /* The IP address list can change so we must query for it */
 341     rx_GetIFInfo();
 342
 343     for (count = 0;
 344          offset < rxi_numNetAddrs && maxSize > 0;
 345          count++, offset++, maxSize--) {
 346         addrBuffer[count] = htonl(rxi_NetAddrs[offset]);
 347         maskBuffer[count] = htonl(myNetMasks[offset]);
 348         mtuBuffer[count]  = htonl(myNetMTUs[offset]);
 349     }
 350     return count;
 351 }
 352 #endif
 353
 354 #ifdef AFS_NT40_ENV
 355 void
 356 rxi_InitMorePackets(void) {
 357     int npackets, ncbufs;
 358
 359     ncbufs = (rx_maxJumboRecvSize - RX_FIRSTBUFFERSIZE);
 360     if (ncbufs > 0) {
 361         ncbufs = ncbufs / RX_CBUFFERSIZE;
 362         npackets = rx_initSendWindow - 1;
 363         rxi_MorePackets(npackets * (ncbufs + 1));
 364     }
 365 }
 366 void
 367 rx_GetIFInfo(void)
 368 {
 369     u_int maxsize;
 370     u_int rxsize;
 371     afs_uint32 i;
 372
 373     LOCK_IF_INIT;
 374     if (Inited) {
 375         if (Inited < 2 && rxi_IsRunning()) {
 376             /* We couldn't initialize more packets earlier.
 377              * Do it now. */
 378             rxi_InitMorePackets();
 379             Inited = 2;
 380         }
 381         UNLOCK_IF_INIT;
 382         return;
 383     }
 384     Inited = 1;
 385     UNLOCK_IF_INIT;
 386
 387     LOCK_IF;
 388     rxi_numNetAddrs = ADDRSPERSITE;
 389     (void)syscfg_GetIFInfo(&rxi_numNetAddrs, rxi_NetAddrs,
 390                            myNetMasks, myNetMTUs, myNetFlags);
 391
 392     for (i = 0; i < rxi_numNetAddrs; i++) {
 393         rxsize = rxi_AdjustIfMTU(myNetMTUs[i] - RX_IPUDP_SIZE);
 394         maxsize =
 395             rxi_nRecvFrags * rxsize + (rxi_nRecvFrags - 1) * UDP_HDR_SIZE;
 396         maxsize = rxi_AdjustMaxMTU(rxsize, maxsize);
 397         if (rx_maxReceiveSize > maxsize) {
 398             rx_maxReceiveSize = MIN(RX_MAX_PACKET_SIZE, maxsize);
 399             rx_maxReceiveSize =
 400                 MIN(rx_maxReceiveSize, rx_maxReceiveSizeUser);
 401         }
 402         if (rx_MyMaxSendSize > maxsize) {
 403             rx_MyMaxSendSize = MIN(RX_MAX_PACKET_SIZE, maxsize);
 404         }
 405     }
 406     UNLOCK_IF;
 407
 408     /*
 409      * If rxi_IsRunning is false, rx_InitHost() has yet to be called
 410      * and we therefore do not have any mutex locks initialized.  As a
 411      * result we cannot call rxi_MorePackets() without crashing.
 412      */
 413     if (!rxi_IsRunning())
 414         return;
 415
 416     rxi_InitMorePackets();
 417 }
 418 #endif
 419
 420 static afs_uint32
 421 fudge_netmask(afs_uint32 addr)
 422 {
 423     afs_uint32 msk;
 424
 425     if (IN_CLASSA(addr))
 426         msk = IN_CLASSA_NET;
 427     else if (IN_CLASSB(addr))
 428         msk = IN_CLASSB_NET;
 429     else if (IN_CLASSC(addr))
 430         msk = IN_CLASSC_NET;
 431     else
 432         msk = 0;
 433
 434     return msk;
 435 }
 436
 437
 438
 439 #if !defined(AFS_AIX_ENV) && !defined(AFS_NT40_ENV) && !defined(AFS_LINUX20_ENV) && !defined(AFS_DARWIN160_ENV)
 440 int
 441 rxi_syscall(afs_uint32 a3, afs_uint32 a4, void *a5)
 442 {
 443     afs_uint32 rcode;
 444     void (*old) (int);
 445
 446     old = signal(SIGSYS, SIG_IGN);
 447
 448 #if defined(AFS_SGI_ENV)
 449     rcode = afs_syscall(AFS_SYSCALL, 28, a3, a4, a5);
 450 #elif defined(AFS_SYSCALL)
 451     rcode = syscall(AFS_SYSCALL, 28 /* AFSCALL_CALL */ , a3, a4, a5);
 452 #else
 453     rcode = -1;
 454 #endif /* AFS_SGI_ENV */
 455
 456     signal(SIGSYS, old);
 457
 458     return rcode;
 459 }
 460 #endif /* AFS_AIX_ENV */
 461
 462 #ifndef AFS_NT40_ENV
 463 void
 464 rx_GetIFInfo(void)
 465 {
 466     int s;
 467     int i, j, len, res;
 468     struct ifconf ifc;
 469     struct ifreq ifs[ADDRSPERSITE];
 470     struct ifreq *ifr;
 471 #ifdef  AFS_AIX41_ENV
 472     char buf[BUFSIZ], *cp, *cplim;
 473 #endif
 474     struct sockaddr_in *a;
 475
 476     LOCK_IF_INIT;
 477     if (Inited) {
 478         UNLOCK_IF_INIT;
 479         return;
 480     }
 481     Inited = 1;
 482     UNLOCK_IF_INIT;
 483     LOCK_IF;
 484     rxi_numNetAddrs = 0;
 485     memset(rxi_NetAddrs, 0, sizeof(rxi_NetAddrs));
 486     memset(myNetFlags, 0, sizeof(myNetFlags));
 487     memset(myNetMTUs, 0, sizeof(myNetMTUs));
 488     memset(myNetMasks, 0, sizeof(myNetMasks));
 489     UNLOCK_IF;
 490     s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 491     if (s == OSI_NULLSOCKET)
 492         return;
 493 #ifdef  AFS_AIX41_ENV
 494     ifc.ifc_len = sizeof(buf);
 495     ifc.ifc_buf = buf;
 496     ifr = ifc.ifc_req;
 497 #else
 498     ifc.ifc_len = sizeof(ifs);
 499     ifc.ifc_buf = (caddr_t) & ifs[0];
 500     memset(&ifs[0], 0, sizeof(ifs));
 501 #endif
 502     res = ioctl(s, SIOCGIFCONF, &ifc);
 503     if (res < 0) {
 504         /* fputs(stderr, "ioctl error IFCONF\n"); */
 505         close(s);
 506         return;
 507     }
 508
 509     LOCK_IF;
 510 #ifdef  AFS_AIX41_ENV
 511 #define size(p) MAX((p).sa_len, sizeof(p))
 512     cplim = buf + ifc.ifc_len;  /*skip over if's with big ifr_addr's */
 513     for (cp = buf; cp < cplim;
 514          cp += sizeof(ifr->ifr_name) + MAX(a->sin_len, sizeof(*a))) {
 515         if (rxi_numNetAddrs >= ADDRSPERSITE)
 516             break;
 517
 518         ifr = (struct ifreq *)cp;
 519 #else
 520     len = ifc.ifc_len / sizeof(struct ifreq);
 521     if (len > ADDRSPERSITE)
 522         len = ADDRSPERSITE;
 523
 524     for (i = 0; i < len; ++i) {
 525         ifr = &ifs[i];
 526         res = ioctl(s, SIOCGIFADDR, ifr);
 527 #endif
 528         if (res < 0) {
 529             /* fputs(stderr, "ioctl error IFADDR\n");
 530              * perror(ifr->ifr_name);   */
 531             continue;
 532         }
 533         a = (struct sockaddr_in *)&ifr->ifr_addr;
 534         if (a->sin_family != AF_INET)
 535             continue;
 536         rxi_NetAddrs[rxi_numNetAddrs] = ntohl(a->sin_addr.s_addr);
 537         if (rx_IsLoopbackAddr(rxi_NetAddrs[rxi_numNetAddrs])) {
 538             /* we don't really care about "localhost" */
 539             continue;
 540         }
 541         for (j = 0; j < rxi_numNetAddrs; j++) {
 542             if (rxi_NetAddrs[j] == rxi_NetAddrs[rxi_numNetAddrs])
 543                 break;
 544         }
 545         if (j < rxi_numNetAddrs)
 546             continue;
 547
 548         /* fprintf(stderr, "if %s addr=%x\n", ifr->ifr_name,
 549          * rxi_NetAddrs[rxi_numNetAddrs]); */
 550
 551 #ifdef SIOCGIFFLAGS
 552         res = ioctl(s, SIOCGIFFLAGS, ifr);
 553         if (res == 0) {
 554             myNetFlags[rxi_numNetAddrs] = ifr->ifr_flags;
 555 #ifdef IFF_LOOPBACK
 556             /* Handle aliased loopbacks as well. */
 557             if (ifr->ifr_flags & IFF_LOOPBACK)
 558                 continue;
 559 #endif
 560             /* fprintf(stderr, "if %s flags=%x\n",
 561              * ifr->ifr_name, ifr->ifr_flags); */
 562         } else {                /*
 563                                  * fputs(stderr, "ioctl error IFFLAGS\n");
 564                                  * perror(ifr->ifr_name); */
 565         }
 566 #endif /* SIOCGIFFLAGS */
 567
 568 #if !defined(AFS_AIX_ENV) && !defined(AFS_LINUX20_ENV) && !defined(AFS_DARWIN160_ENV)
 569         /* this won't run on an AIX system w/o a cache manager */
 570         rxi_syscallp = rxi_syscall;
 571 #endif
 572
 573         /* If I refer to kernel extensions that aren't loaded on AIX, the
 574          * program refuses to load and run, so I simply can't include the
 575          * following code.  Fortunately, AIX is the one operating system in
 576          * which the subsequent ioctl works reliably. */
 577         if (rxi_syscallp) {
 578             if ((*rxi_syscallp) (20 /*AFSOP_GETMTU */ ,
 579                                  htonl(rxi_NetAddrs[rxi_numNetAddrs]),
 580                                  &(myNetMTUs[rxi_numNetAddrs]))) {
 581                 /* fputs(stderr, "syscall error GETMTU\n");
 582                  * perror(ifr->ifr_name); */
 583                 myNetMTUs[rxi_numNetAddrs] = 0;
 584             }
 585             if ((*rxi_syscallp) (42 /*AFSOP_GETMASK */ ,
 586                                  htonl(rxi_NetAddrs[rxi_numNetAddrs]),
 587                                  &(myNetMasks[rxi_numNetAddrs]))) {
 588                 /* fputs(stderr, "syscall error GETMASK\n");
 589                  * perror(ifr->ifr_name); */
 590                 myNetMasks[rxi_numNetAddrs] = 0;
 591             } else
 592                 myNetMasks[rxi_numNetAddrs] =
 593                     ntohl(myNetMasks[rxi_numNetAddrs]);
 594             /* fprintf(stderr, "if %s mask=0x%x\n",
 595              * ifr->ifr_name, myNetMasks[rxi_numNetAddrs]); */
 596         }
 597
 598         if (myNetMTUs[rxi_numNetAddrs] == 0) {
 599             myNetMTUs[rxi_numNetAddrs] = OLD_MAX_PACKET_SIZE + RX_IPUDP_SIZE;
 600 #ifdef SIOCGIFMTU
 601             res = ioctl(s, SIOCGIFMTU, ifr);
 602             if ((res == 0) && (ifr->ifr_metric > 128)) {        /* sanity check */
 603                 myNetMTUs[rxi_numNetAddrs] = ifr->ifr_metric;
 604                 /* fprintf(stderr, "if %s mtu=%d\n",
 605                  * ifr->ifr_name, ifr->ifr_metric); */
 606             } else {
 607                 /* fputs(stderr, "ioctl error IFMTU\n");
 608                  * perror(ifr->ifr_name); */
 609             }
 610 #endif
 611         }
 612
 613         if (myNetMasks[rxi_numNetAddrs] == 0) {
 614             myNetMasks[rxi_numNetAddrs] =
 615                 fudge_netmask(rxi_NetAddrs[rxi_numNetAddrs]);
 616 #ifdef SIOCGIFNETMASK
 617             res = ioctl(s, SIOCGIFNETMASK, ifr);
 618             if (res == 0) {
 619                 a = (struct sockaddr_in *)&ifr->ifr_addr;
 620                 myNetMasks[rxi_numNetAddrs] = ntohl(a->sin_addr.s_addr);
 621                 /* fprintf(stderr, "if %s subnetmask=0x%x\n",
 622                  * ifr->ifr_name, myNetMasks[rxi_numNetAddrs]); */
 623             } else {
 624                 /* fputs(stderr, "ioctl error IFMASK\n");
 625                  * perror(ifr->ifr_name); */
 626             }
 627 #endif
 628         }
 629
 630         if (!rx_IsLoopbackAddr(rxi_NetAddrs[rxi_numNetAddrs])) {        /* ignore lo0 */
 631             int maxsize;
 632             maxsize =
 633                 rxi_nRecvFrags * (myNetMTUs[rxi_numNetAddrs] - RX_IP_SIZE);
 634             maxsize -= UDP_HDR_SIZE;    /* only the first frag has a UDP hdr */
 635             if (rx_maxReceiveSize < maxsize)
 636                 rx_maxReceiveSize = MIN(RX_MAX_PACKET_SIZE, maxsize);
 637             ++rxi_numNetAddrs;
 638         }
 639     }
 640     UNLOCK_IF;
 641     close(s);
 642
 643     /* have to allocate at least enough to allow a single packet to reach its
 644      * maximum size, so ReadPacket will work.  Allocate enough for a couple
 645      * of packets to do so, for good measure */
 646     {
 647         int npackets, ncbufs;
 648
 649         rx_maxJumboRecvSize =
 650             RX_HEADER_SIZE + rxi_nDgramPackets * RX_JUMBOBUFFERSIZE +
 651             (rxi_nDgramPackets - 1) * RX_JUMBOHEADERSIZE;
 652         rx_maxJumboRecvSize = MAX(rx_maxJumboRecvSize, rx_maxReceiveSize);
 653         ncbufs = (rx_maxJumboRecvSize - RX_FIRSTBUFFERSIZE);
 654         if (ncbufs > 0) {
 655             ncbufs = ncbufs / RX_CBUFFERSIZE;
 656             npackets = rx_initSendWindow - 1;
 657             rxi_MorePackets(npackets * (ncbufs + 1));
 658         }
 659     }
 660 }
 661 #endif /* AFS_NT40_ENV */
 662
 663 /* Called from rxi_FindPeer, when initializing a clear rx_peer structure,
 664  * to get interesting information.
 665  * Curiously enough, the rx_peerHashTable_lock currently protects the
 666  * Inited variable (and hence rx_GetIFInfo). When the fs suite uses
 667  * pthreads, this issue will need to be revisited.
 668  */
 669
 670 void
 671 rxi_InitPeerParams(struct rx_peer *pp)
 672 {
 673     afs_uint32 ppaddr;
 674     u_short rxmtu;
 675     int ix;
 676 #ifdef AFS_ADAPT_PMTU
 677     int sock;
 678     struct sockaddr_in addr;
 679 #endif
 680
 681     LOCK_IF_INIT;
 682     if (!Inited) {
 683         UNLOCK_IF_INIT;
 684         /*
 685          * there's a race here since more than one thread could call
 686          * rx_GetIFInfo.  The race stops in rx_GetIFInfo.
 687          */
 688         rx_GetIFInfo();
 689     } else {
 690         UNLOCK_IF_INIT;
 691     }
 692
 693     /* try to second-guess IP, and identify which link is most likely to
 694      * be used for traffic to/from this host. */
 695     ppaddr = ntohl(pp->host);
 696
 697     pp->ifMTU = 0;
 698     rx_rto_setPeerTimeoutSecs(pp, 2);
 699     /* I don't initialize these, because I presume they are bzero'd...
 700      * pp->burstSize pp->burst pp->burstWait.sec pp->burstWait.usec
 701      */
 702
 703     LOCK_IF;
 704     for (ix = 0; ix < rxi_numNetAddrs; ++ix) {
 705         if ((rxi_NetAddrs[ix] & myNetMasks[ix]) == (ppaddr & myNetMasks[ix])) {
 706 #ifdef IFF_POINTOPOINT
 707             if (myNetFlags[ix] & IFF_POINTOPOINT)
 708                 rx_rto_setPeerTimeoutSecs(pp, 4);
 709 #endif /* IFF_POINTOPOINT */
 710
 711             rxmtu = myNetMTUs[ix] - RX_IPUDP_SIZE;
 712             if (rxmtu < RX_MIN_PACKET_SIZE)
 713                 rxmtu = RX_MIN_PACKET_SIZE;
 714             if (pp->ifMTU < rxmtu)
 715                 pp->ifMTU = MIN(rx_MyMaxSendSize, rxmtu);
 716         }
 717     }
 718     UNLOCK_IF;
 719     if (!pp->ifMTU) {           /* not local */
 720         rx_rto_setPeerTimeoutSecs(pp, 3);
 721         pp->ifMTU = MIN(rx_MyMaxSendSize, RX_REMOTE_PACKET_SIZE);
 722     }
 723 #ifdef AFS_ADAPT_PMTU
 724     sock=socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
 725     if (sock != OSI_NULLSOCKET) {
 726         addr.sin_family = AF_INET;
 727         addr.sin_addr.s_addr = pp->host;
 728         addr.sin_port = pp->port;
 729         memset(&addr.sin_zero, 0, sizeof(addr.sin_zero));
 730         if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0) {
 731             int mtu=0;
 732             socklen_t s = sizeof(mtu);
 733             if (getsockopt(sock, SOL_IP, IP_MTU, &mtu, &s)== 0) {
 734                 pp->ifMTU = MIN(mtu - RX_IPUDP_SIZE, pp->ifMTU);
 735             }
 736         }
 737 # ifdef AFS_NT40_ENV
 738         closesocket(sock);
 739 # else
 740         close(sock);
 741 # endif
 742     }
 743 #endif
 744     pp->ifMTU = rxi_AdjustIfMTU(pp->ifMTU);
 745     pp->maxMTU = OLD_MAX_PACKET_SIZE;   /* for compatibility with old guys */
 746     pp->natMTU = MIN((int)pp->ifMTU, OLD_MAX_PACKET_SIZE);
 747     pp->maxDgramPackets =
 748         MIN(rxi_nDgramPackets,
 749             rxi_AdjustDgramPackets(rxi_nSendFrags, pp->ifMTU));
 750     pp->ifDgramPackets =
 751         MIN(rxi_nDgramPackets,
 752             rxi_AdjustDgramPackets(rxi_nSendFrags, pp->ifMTU));
 753     pp->maxDgramPackets = 1;
 754     /* Initialize slow start parameters */
 755     pp->MTU = MIN(pp->natMTU, pp->maxMTU);
 756     pp->cwind = 1;
 757     pp->nDgramPackets = 1;
 758     pp->congestSeq = 0;
 759 }
 760
 761 /* Don't expose jumobgram internals. */
 762 void
 763 rx_SetNoJumbo(void)
 764 {
 765     rx_maxReceiveSize = OLD_MAX_PACKET_SIZE;
 766     rxi_nSendFrags = rxi_nRecvFrags = 1;
 767 }
 768
 769 /* Override max MTU.  If rx_SetNoJumbo is called, it must be
 770    called before calling rx_SetMaxMTU since SetNoJumbo clobbers rx_maxReceiveSize */
 771 int
 772 rx_SetMaxMTU(int mtu)
 773 {
 774     if (mtu < RX_MIN_PACKET_SIZE || mtu > RX_MAX_PACKET_DATA_SIZE)
 775         return EINVAL;
 776
 777     rx_MyMaxSendSize = rx_maxReceiveSizeUser = rx_maxReceiveSize = mtu;
 778
 779     return 0;
 780 }
 781
 782 #ifdef AFS_RXERRQ_ENV
 783 int
 784 rxi_HandleSocketError(int socket)
 785 {
 786     struct msghdr msg;
 787     struct cmsghdr *cmsg;
 788     struct sock_extended_err *err;
 789     struct sockaddr_in addr;
 790     char controlmsgbuf[256];
 791     int code;
 792
 793     msg.msg_name = &addr;
 794     msg.msg_namelen = sizeof(addr);
 795     msg.msg_iov = NULL;
 796     msg.msg_iovlen = 0;
 797     msg.msg_control = controlmsgbuf;
 798     msg.msg_controllen = 256;
 799     msg.msg_flags = 0;
 800     code = recvmsg(socket, &msg, MSG_ERRQUEUE|MSG_DONTWAIT|MSG_TRUNC);
 801
 802     if (code < 0 || !(msg.msg_flags & MSG_ERRQUEUE))
 803         return 0;
 804
 805     for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
 806         if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR) {
 807             err = (struct sock_extended_err *)CMSG_DATA(cmsg);
 808             rxi_ProcessNetError(err, addr.sin_addr.s_addr, addr.sin_port);
 809         }
 810     }
 811
 812     return 1;
 813 }
 814 #endif