usr.sbin/mopd/common/loop-bsd.c

   1 /*      $NetBSD: loop-bsd.c,v 1.9 2006/10/07 17:27:57 elad Exp $        */
   2
   3 /*
   4  * Copyright (c) 1993-95 Mats O Jansson.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 #ifndef lint
  29 __RCSID("$NetBSD: loop-bsd.c,v 1.9 2006/10/07 17:27:57 elad Exp $");
  30 #endif
  31
  32 #include <errno.h>
  33 #include <stdlib.h>
  34 #include <strings.h>
  35 #include <unistd.h>
  36 #if defined(__bsdi__) || defined(__FreeBSD__) || defined(__NetBSD__)
  37 #include <sys/time.h>
  38 #endif
  39 #include <net/bpf.h>
  40 #include <sys/ioctl.h>
  41 #include <sys/poll.h>
  42 #include <assert.h>
  43
  44 #include "os.h"
  45 #include "common.h"
  46 #include "device.h"
  47 #include "mopdef.h"
  48 #include "log.h"
  49
  50 int
  51 mopOpenRC(p, trans)
  52         struct if_info *p;
  53         int     trans;
  54 {
  55 #ifndef NORC
  56         return (*(p->iopen))(p->if_name,
  57                              O_RDWR,
  58                              MOP_K_PROTO_RC,
  59                              trans);
  60 #else
  61         return -1;
  62 #endif
  63 }
  64
  65 int
  66 mopOpenDL(p, trans)
  67         struct if_info *p;
  68         int     trans;
  69 {
  70 #ifndef NODL
  71         return (*(p->iopen))(p->if_name,
  72                              O_RDWR,
  73                              MOP_K_PROTO_DL,
  74                              trans);
  75 #else
  76         return -1;
  77 #endif
  78 }
  79
  80 void
  81 mopReadRC()
  82 {
  83 }
  84
  85 void
  86 mopReadDL()
  87 {
  88 }
  89
  90 /*
  91  * The list of all interfaces that are being listened to.  loop()
  92  * "polls" on the descriptors in this list.
  93  */
  94 struct if_info *iflist;
  95
  96 void   mopProcess    __P((struct if_info *, u_char *));
  97
  98 /*
  99  * Loop indefinitely listening for MOP requests on the
 100  * interfaces in 'iflist'.
 101  */
 102 void
 103 Loop()
 104 {
 105         u_char *buf, *bp, *ep;
 106         int     cc, n, m;
 107         struct  pollfd *set;
 108         int     bufsize;
 109         struct  if_info *ii;
 110
 111         if (iflist == 0)
 112                 mopLogErrX("no interfaces");
 113         if (iflist->fd != -1) {
 114                 if (ioctl(iflist->fd, BIOCGBLEN, (caddr_t) & bufsize) < 0)
 115                         mopLogErr("BIOCGBLEN");
 116         } else
 117                 mopLogErrX("cannot get buffer size");
 118         buf = (u_char *) malloc((unsigned) bufsize);
 119         if (buf == 0)
 120                 mopLogErr("malloc");
 121         /*
 122          * Find the highest numbered file descriptor for poll().
 123          * Initialize the set of descriptors to listen to.
 124          */
 125         for (ii = iflist, n = 0; ii; ii = ii->next, n++)
 126                 ;
 127         set = malloc(n * sizeof(*set));
 128         for (ii = iflist, m = 0; ii; ii = ii->next, m++) {
 129                 assert(ii->fd != -1);
 130                 set[m].fd = ii->fd;
 131                 set[m].events = POLLIN;
 132         }
 133         for (;;) {
 134                 if (poll(set, n, INFTIM) < 0)
 135                         mopLogErr("poll");
 136                 for (ii = iflist, m = 0; ii; ii = ii->next, m++) {
 137                         if (!(set[m].revents & POLLIN))
 138                                 continue;
 139         again:
 140                         cc = read(ii->fd, (char *) buf, bufsize);
 141                         /* Don't choke when we get ptraced */
 142                         if (cc < 0 && errno == EINTR)
 143                                 goto again;
 144                         /* Due to a SunOS bug, after 2^31 bytes, the file
 145                          * offset overflows and read fails with EINVAL.  The
 146                          * lseek() to 0 will fix things. */
 147                         if (cc < 0) {
 148                                 if (errno == EINVAL &&
 149                                     (lseek(ii->fd, 0, SEEK_CUR) + bufsize) < 0) {
 150                                         (void) lseek(ii->fd, 0, 0);
 151                                         goto again;
 152                                 }
 153                                 mopLogErr("read");
 154                         }
 155                         /* Loop through the packet(s) */
 156 #define bhp ((struct bpf_hdr *)bp)
 157                         bp = buf;
 158                         ep = bp + cc;
 159                         while (bp < ep) {
 160                                 int caplen, hdrlen;
 161
 162                                 caplen = bhp->bh_caplen;
 163                                 hdrlen = bhp->bh_hdrlen;
 164                                 mopProcess(ii, bp + hdrlen);
 165                                 bp += BPF_WORDALIGN(hdrlen + caplen);
 166                         }
 167                 }
 168         }
 169 }