1 /* $OpenBSD: loop-bsd.c,v 1.7 2003/06/02 21:38:39 maja 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 #ifndef LINT 28 static char rcsid[] = "$OpenBSD: loop-bsd.c,v 1.7 2003/06/02 21:38:39 maja Exp $"; 29 #endif 30 31 #include <stdlib.h> 32 #include <string.h> 33 #include <unistd.h> 34 #if defined(__bsdi__) || defined(__FreeBSD__) 35 #include <sys/time.h> 36 #endif 37 #include <net/bpf.h> 38 #include <sys/ioctl.h> 39 #include <sys/errno.h> 40 41 #include "os.h" 42 #include "common/common.h" 43 #include "common/mopdef.h" 44 45 int 46 mopOpenRC(p, trans) 47 struct if_info *p; 48 int trans; 49 { 50 #ifndef NORC 51 return (*(p->iopen))(p->if_name, 52 O_RDWR, 53 MOP_K_PROTO_RC, 54 trans); 55 #else 56 return -1; 57 #endif 58 } 59 60 int 61 mopOpenDL(p, trans) 62 struct if_info *p; 63 int trans; 64 { 65 #ifndef NODL 66 return (*(p->iopen))(p->if_name, 67 O_RDWR, 68 MOP_K_PROTO_DL, 69 trans); 70 #else 71 return -1; 72 #endif 73 } 74 75 void 76 mopReadRC() 77 { 78 } 79 80 void 81 mopReadDL() 82 { 83 } 84 85 /* 86 * The list of all interfaces that are being listened to. loop() 87 * "selects" on the descriptors in this list. 88 */ 89 struct if_info *iflist; 90 91 void mopProcess(struct if_info *, u_char *); 92 93 /* 94 * Loop indefinitely listening for MOP requests on the 95 * interfaces in 'iflist'. 96 */ 97 void 98 Loop() 99 { 100 u_char *buf, *bp, *ep; 101 int cc; 102 fd_set fds, listeners; 103 int bufsize, maxfd = 0; 104 struct if_info *ii; 105 106 if (iflist == 0) { 107 syslog(LOG_ERR, "no interfaces"); 108 exit(0); 109 } 110 if (iflist->fd != -1) { 111 if (ioctl(iflist->fd, BIOCGBLEN, (caddr_t) & bufsize) < 0) { 112 syslog(LOG_ERR, "BIOCGBLEN: %m"); 113 exit(0); 114 } 115 } 116 buf = (u_char *) malloc((unsigned) bufsize); 117 if (buf == 0) { 118 syslog(LOG_ERR, "malloc: %m"); 119 exit(0); 120 } 121 /* 122 * Find the highest numbered file descriptor for select(). 123 * Initialize the set of descriptors to listen to. 124 */ 125 FD_ZERO(&fds); 126 for (ii = iflist; ii; ii = ii->next) { 127 if (ii->fd != -1) { 128 FD_SET(ii->fd, &fds); 129 if (ii->fd > maxfd) 130 maxfd = ii->fd; 131 } 132 } 133 while (1) { 134 listeners = fds; 135 if (select(maxfd + 1, &listeners, (fd_set *) 0, 136 (fd_set *) 0, (struct timeval *) 0) < 0) { 137 syslog(LOG_ERR, "select: %m"); 138 exit(0); 139 } 140 for (ii = iflist; ii; ii = ii->next) { 141 if (ii->fd != -1) { 142 if (!FD_ISSET(ii->fd, &listeners)) 143 continue; 144 } 145 again: 146 cc = read(ii->fd, (char *) buf, bufsize); 147 /* Don't choke when we get ptraced */ 148 if (cc < 0 && errno == EINTR) 149 goto again; 150 /* Due to a SunOS bug, after 2^31 bytes, the file 151 * offset overflows and read fails with EINVAL. The 152 * lseek() to 0 will fix things. */ 153 if (cc < 0) { 154 if (errno == EINVAL && 155 (lseek(ii->fd, 0, SEEK_CUR) + bufsize) < 0) { 156 (void) lseek(ii->fd, 0, 0); 157 goto again; 158 } 159 syslog(LOG_ERR, "read: %m"); 160 exit(0); 161 } 162 /* Loop through the packet(s) */ 163 #define bhp ((struct bpf_hdr *)bp) 164 bp = buf; 165 ep = bp + cc; 166 while (bp < ep) { 167 int caplen, hdrlen; 168 169 caplen = bhp->bh_caplen; 170 hdrlen = bhp->bh_hdrlen; 171 mopProcess(ii, bp + hdrlen); 172 bp += BPF_WORDALIGN(hdrlen + caplen); 173 } 174 } 175 } 176 } 177