1 /* 2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 #ifndef lint 22 static const char rcsid[] = 23 "@(#) $Header: /tcpdump/master/libpcap/pcap-nit.c,v 1.39 2000/10/28 00:01:29 guy Exp $ (LBL)"; 24 #endif 25 26 #ifdef HAVE_CONFIG_H 27 #include "config.h" 28 #endif 29 30 #include <sys/types.h> 31 #include <sys/time.h> 32 #include <sys/timeb.h> 33 #include <sys/file.h> 34 #include <sys/ioctl.h> 35 #include <sys/socket.h> 36 37 #include <net/if.h> 38 #include <net/nit.h> 39 40 #include <netinet/in.h> 41 #include <netinet/in_systm.h> 42 #include <netinet/ip.h> 43 #include <netinet/if_ether.h> 44 #include <netinet/ip_var.h> 45 #include <netinet/udp.h> 46 #include <netinet/udp_var.h> 47 #include <netinet/tcp.h> 48 #include <netinet/tcpip.h> 49 50 #include <ctype.h> 51 #include <errno.h> 52 #include <stdio.h> 53 54 #include "pcap-int.h" 55 56 #ifdef HAVE_OS_PROTO_H 57 #include "os-proto.h" 58 #endif 59 60 /* 61 * The chunk size for NIT. This is the amount of buffering 62 * done for read calls. 63 */ 64 #define CHUNKSIZE (2*1024) 65 66 /* 67 * The total buffer space used by NIT. 68 */ 69 #define BUFSPACE (4*CHUNKSIZE) 70 71 /* Forwards */ 72 static int nit_setflags(int, int, int, char *); 73 74 int 75 pcap_stats(pcap_t *p, struct pcap_stat *ps) 76 { 77 78 *ps = p->md.stat; 79 return (0); 80 } 81 82 int 83 pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 84 { 85 register int cc, n; 86 register struct bpf_insn *fcode = p->fcode.bf_insns; 87 register u_char *bp, *cp, *ep; 88 register struct nit_hdr *nh; 89 register int caplen; 90 91 cc = p->cc; 92 if (cc == 0) { 93 cc = read(p->fd, (char *)p->buffer, p->bufsize); 94 if (cc < 0) { 95 if (errno == EWOULDBLOCK) 96 return (0); 97 snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s", 98 pcap_strerror(errno)); 99 return (-1); 100 } 101 bp = p->buffer; 102 } else 103 bp = p->bp; 104 105 /* 106 * Loop through each packet. The increment expression 107 * rounds up to the next int boundary past the end of 108 * the previous packet. 109 */ 110 n = 0; 111 ep = bp + cc; 112 while (bp < ep) { 113 nh = (struct nit_hdr *)bp; 114 cp = bp + sizeof(*nh); 115 116 switch (nh->nh_state) { 117 118 case NIT_CATCH: 119 break; 120 121 case NIT_NOMBUF: 122 case NIT_NOCLUSTER: 123 case NIT_NOSPACE: 124 p->md.stat.ps_drop = nh->nh_dropped; 125 continue; 126 127 case NIT_SEQNO: 128 continue; 129 130 default: 131 snprintf(p->errbuf, sizeof(p->errbuf), 132 "bad nit state %d", nh->nh_state); 133 return (-1); 134 } 135 ++p->md.stat.ps_recv; 136 bp += ((sizeof(struct nit_hdr) + nh->nh_datalen + 137 sizeof(int) - 1) & ~(sizeof(int) - 1)); 138 139 caplen = nh->nh_wirelen; 140 if (caplen > p->snapshot) 141 caplen = p->snapshot; 142 if (bpf_filter(fcode, cp, nh->nh_wirelen, caplen)) { 143 struct pcap_pkthdr h; 144 h.ts = nh->nh_timestamp; 145 h.len = nh->nh_wirelen; 146 h.caplen = caplen; 147 (*callback)(user, &h, cp); 148 if (++n >= cnt && cnt >= 0) { 149 p->cc = ep - bp; 150 p->bp = bp; 151 return (n); 152 } 153 } 154 } 155 p->cc = 0; 156 return (n); 157 } 158 159 static int 160 nit_setflags(int fd, int promisc, int to_ms, char *ebuf) 161 { 162 struct nit_ioc nioc; 163 164 memset(&nioc, 0, sizeof(nioc)); 165 nioc.nioc_bufspace = BUFSPACE; 166 nioc.nioc_chunksize = CHUNKSIZE; 167 nioc.nioc_typetomatch = NT_ALLTYPES; 168 nioc.nioc_snaplen = p->snapshot; 169 nioc.nioc_bufalign = sizeof(int); 170 nioc.nioc_bufoffset = 0; 171 172 if (to_ms != 0) { 173 nioc.nioc_flags |= NF_TIMEOUT; 174 nioc.nioc_timeout.tv_sec = to_ms / 1000; 175 nioc.nioc_timeout.tv_usec = (to_ms * 1000) % 1000000; 176 } 177 if (promisc) 178 nioc.nioc_flags |= NF_PROMISC; 179 180 if (ioctl(fd, SIOCSNIT, &nioc) < 0) { 181 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCSNIT: %s", 182 pcap_strerror(errno)); 183 return (-1); 184 } 185 return (0); 186 } 187 188 pcap_t * 189 pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf) 190 { 191 int fd; 192 struct sockaddr_nit snit; 193 register pcap_t *p; 194 195 p = (pcap_t *)malloc(sizeof(*p)); 196 if (p == NULL) { 197 strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE); 198 return (NULL); 199 } 200 201 if (snaplen < 96) 202 /* 203 * NIT requires a snapshot length of at least 96. 204 */ 205 snaplen = 96; 206 207 memset(p, 0, sizeof(*p)); 208 p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW); 209 if (fd < 0) { 210 snprintf(ebuf, PCAP_ERRBUF_SIZE, 211 "socket: %s", pcap_strerror(errno)); 212 goto bad; 213 } 214 snit.snit_family = AF_NIT; 215 (void)strncpy(snit.snit_ifname, device, NITIFSIZ); 216 217 if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) { 218 snprintf(ebuf, PCAP_ERRBUF_SIZE, 219 "bind: %s: %s", snit.snit_ifname, pcap_strerror(errno)); 220 goto bad; 221 } 222 p->snapshot = snaplen; 223 nit_setflags(p->fd, promisc, to_ms, ebuf); 224 225 /* 226 * NIT supports only ethernets. 227 */ 228 p->linktype = DLT_EN10MB; 229 230 p->bufsize = BUFSPACE; 231 p->buffer = (u_char *)malloc(p->bufsize); 232 if (p->buffer == NULL) { 233 strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE); 234 goto bad; 235 } 236 return (p); 237 bad: 238 if (fd >= 0) 239 close(fd); 240 free(p); 241 return (NULL); 242 } 243 244 int 245 pcap_setfilter(pcap_t *p, struct bpf_program *fp) 246 { 247 248 if (install_bpf_program(p, fp) < 0) 249 return (-1); 250 return (0); 251 } 252