| /* |
| * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996 |
| * The Regents of the University of California. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that: (1) source code distributions |
| * retain the above copyright notice and this paragraph in its entirety, (2) |
| * distributions including binary code include the above copyright notice and |
| * this paragraph in its entirety in the documentation or other materials |
| * provided with the distribution, and (3) all advertising materials mentioning |
| * features or use of this software display the following acknowledgement: |
| * ``This product includes software developed by the University of California, |
| * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| * the University nor the names of its contributors may be used to endorse |
| * or promote products derived from this software without specific prior |
| * written permission. |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| */ |
| #ifndef lint |
| static const char rcsid[] _U_ = |
| "@(#) $Header: /tcpdump/master/libpcap/pcap-nit.c,v 1.57.2.1 2005/05/03 18:54:37 guy Exp $ (LBL)"; |
| #endif |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include <sys/types.h> |
| #include <sys/time.h> |
| #include <sys/timeb.h> |
| #include <sys/file.h> |
| #include <sys/ioctl.h> |
| #include <sys/socket.h> |
| |
| #include <net/if.h> |
| #include <net/nit.h> |
| |
| #include <netinet/in.h> |
| #include <netinet/in_systm.h> |
| #include <netinet/ip.h> |
| #include <netinet/if_ether.h> |
| #include <netinet/ip_var.h> |
| #include <netinet/udp.h> |
| #include <netinet/udp_var.h> |
| #include <netinet/tcp.h> |
| #include <netinet/tcpip.h> |
| |
| #include <ctype.h> |
| #include <errno.h> |
| #include <stdio.h> |
| |
| #include "pcap-int.h" |
| |
| #ifdef HAVE_OS_PROTO_H |
| #include "os-proto.h" |
| #endif |
| |
| /* |
| * The chunk size for NIT. This is the amount of buffering |
| * done for read calls. |
| */ |
| #define CHUNKSIZE (2*1024) |
| |
| /* |
| * The total buffer space used by NIT. |
| */ |
| #define BUFSPACE (4*CHUNKSIZE) |
| |
| /* Forwards */ |
| static int nit_setflags(int, int, int, char *); |
| |
| static int |
| pcap_stats_nit(pcap_t *p, struct pcap_stat *ps) |
| { |
| |
| /* |
| * "ps_recv" counts packets handed to the filter, not packets |
| * that passed the filter. As filtering is done in userland, |
| * this does not include packets dropped because we ran out |
| * of buffer space. |
| * |
| * "ps_drop" presumably counts packets dropped by the socket |
| * because of flow control requirements or resource exhaustion; |
| * it doesn't count packets dropped by the interface driver. |
| * As filtering is done in userland, it counts packets regardless |
| * of whether they would've passed the filter. |
| * |
| * These statistics don't include packets not yet read from the |
| * kernel by libpcap or packets not yet read from libpcap by the |
| * application. |
| */ |
| *ps = p->md.stat; |
| return (0); |
| } |
| |
| static int |
| pcap_read_nit(pcap_t *p, int cnt, pcap_handler callback, u_char *user) |
| { |
| register int cc, n; |
| register struct bpf_insn *fcode = p->fcode.bf_insns; |
| register u_char *bp, *cp, *ep; |
| register struct nit_hdr *nh; |
| register int caplen; |
| |
| cc = p->cc; |
| if (cc == 0) { |
| cc = read(p->fd, (char *)p->buffer, p->bufsize); |
| if (cc < 0) { |
| if (errno == EWOULDBLOCK) |
| return (0); |
| snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| bp = p->buffer; |
| } else |
| bp = p->bp; |
| |
| /* |
| * Loop through each packet. The increment expression |
| * rounds up to the next int boundary past the end of |
| * the previous packet. |
| */ |
| n = 0; |
| ep = bp + cc; |
| while (bp < ep) { |
| /* |
| * Has "pcap_breakloop()" been called? |
| * If so, return immediately - if we haven't read any |
| * packets, clear the flag and return -2 to indicate |
| * that we were told to break out of the loop, otherwise |
| * leave the flag set, so that the *next* call will break |
| * out of the loop without having read any packets, and |
| * return the number of packets we've processed so far. |
| */ |
| if (p->break_loop) { |
| if (n == 0) { |
| p->break_loop = 0; |
| return (-2); |
| } else { |
| p->cc = ep - bp; |
| p->bp = bp; |
| return (n); |
| } |
| } |
| |
| nh = (struct nit_hdr *)bp; |
| cp = bp + sizeof(*nh); |
| |
| switch (nh->nh_state) { |
| |
| case NIT_CATCH: |
| break; |
| |
| case NIT_NOMBUF: |
| case NIT_NOCLUSTER: |
| case NIT_NOSPACE: |
| p->md.stat.ps_drop = nh->nh_dropped; |
| continue; |
| |
| case NIT_SEQNO: |
| continue; |
| |
| default: |
| snprintf(p->errbuf, sizeof(p->errbuf), |
| "bad nit state %d", nh->nh_state); |
| return (-1); |
| } |
| ++p->md.stat.ps_recv; |
| bp += ((sizeof(struct nit_hdr) + nh->nh_datalen + |
| sizeof(int) - 1) & ~(sizeof(int) - 1)); |
| |
| caplen = nh->nh_wirelen; |
| if (caplen > p->snapshot) |
| caplen = p->snapshot; |
| if (bpf_filter(fcode, cp, nh->nh_wirelen, caplen)) { |
| struct pcap_pkthdr h; |
| h.ts = nh->nh_timestamp; |
| h.len = nh->nh_wirelen; |
| h.caplen = caplen; |
| (*callback)(user, &h, cp); |
| if (++n >= cnt && cnt >= 0) { |
| p->cc = ep - bp; |
| p->bp = bp; |
| return (n); |
| } |
| } |
| } |
| p->cc = 0; |
| return (n); |
| } |
| |
| static int |
| pcap_inject_nit(pcap_t *p, const void *buf, size_t size) |
| { |
| struct sockaddr sa; |
| int ret; |
| |
| memset(&sa, 0, sizeof(sa)); |
| strncpy(sa.sa_data, device, sizeof(sa.sa_data)); |
| ret = sendto(p->fd, buf, size, 0, &sa, sizeof(sa)); |
| if (ret == -1) { |
| snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| return (ret); |
| } |
| |
| static int |
| nit_setflags(int fd, int promisc, int to_ms, char *ebuf) |
| { |
| struct nit_ioc nioc; |
| |
| memset(&nioc, 0, sizeof(nioc)); |
| nioc.nioc_bufspace = BUFSPACE; |
| nioc.nioc_chunksize = CHUNKSIZE; |
| nioc.nioc_typetomatch = NT_ALLTYPES; |
| nioc.nioc_snaplen = p->snapshot; |
| nioc.nioc_bufalign = sizeof(int); |
| nioc.nioc_bufoffset = 0; |
| |
| if (to_ms != 0) { |
| nioc.nioc_flags |= NF_TIMEOUT; |
| nioc.nioc_timeout.tv_sec = to_ms / 1000; |
| nioc.nioc_timeout.tv_usec = (to_ms * 1000) % 1000000; |
| } |
| if (promisc) |
| nioc.nioc_flags |= NF_PROMISC; |
| |
| if (ioctl(fd, SIOCSNIT, &nioc) < 0) { |
| snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCSNIT: %s", |
| pcap_strerror(errno)); |
| return (-1); |
| } |
| return (0); |
| } |
| |
| static void |
| pcap_close_nit(pcap_t *p) |
| { |
| pcap_close_common(p); |
| if (p->device != NULL) |
| free(p->device); |
| } |
| |
| pcap_t * |
| pcap_open_live(const char *device, int snaplen, int promisc, int to_ms, |
| char *ebuf) |
| { |
| int fd; |
| struct sockaddr_nit snit; |
| register pcap_t *p; |
| |
| p = (pcap_t *)malloc(sizeof(*p)); |
| if (p == NULL) { |
| strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE); |
| return (NULL); |
| } |
| |
| if (snaplen < 96) |
| /* |
| * NIT requires a snapshot length of at least 96. |
| */ |
| snaplen = 96; |
| |
| memset(p, 0, sizeof(*p)); |
| p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW); |
| if (fd < 0) { |
| snprintf(ebuf, PCAP_ERRBUF_SIZE, |
| "socket: %s", pcap_strerror(errno)); |
| goto bad; |
| } |
| snit.snit_family = AF_NIT; |
| (void)strncpy(snit.snit_ifname, device, NITIFSIZ); |
| |
| if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) { |
| snprintf(ebuf, PCAP_ERRBUF_SIZE, |
| "bind: %s: %s", snit.snit_ifname, pcap_strerror(errno)); |
| goto bad; |
| } |
| p->snapshot = snaplen; |
| nit_setflags(p->fd, promisc, to_ms, ebuf); |
| |
| /* |
| * NIT supports only ethernets. |
| */ |
| p->linktype = DLT_EN10MB; |
| |
| p->bufsize = BUFSPACE; |
| p->buffer = (u_char *)malloc(p->bufsize); |
| if (p->buffer == NULL) { |
| strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE); |
| goto bad; |
| } |
| |
| /* |
| * We need the device name in order to send packets. |
| */ |
| p->device = strdup(device); |
| if (p->device == NULL) { |
| strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE); |
| free(p->buffer); |
| goto bad; |
| } |
| |
| /* |
| * "p->fd" is a socket, so "select()" should work on it. |
| */ |
| p->selectable_fd = p->fd; |
| |
| /* |
| * This is (presumably) a real Ethernet capture; give it a |
| * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so |
| * that an application can let you choose it, in case you're |
| * capturing DOCSIS traffic that a Cisco Cable Modem |
| * Termination System is putting out onto an Ethernet (it |
| * doesn't put an Ethernet header onto the wire, it puts raw |
| * DOCSIS frames out on the wire inside the low-level |
| * Ethernet framing). |
| */ |
| p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2); |
| /* |
| * If that fails, just leave the list empty. |
| */ |
| if (p->dlt_list != NULL) { |
| p->dlt_list[0] = DLT_EN10MB; |
| p->dlt_list[1] = DLT_DOCSIS; |
| p->dlt_count = 2; |
| } |
| |
| p->read_op = pcap_read_nit; |
| p->inject_op = pcap_inject_nit; |
| p->setfilter_op = install_bpf_program; /* no kernel filtering */ |
| p->setdirection_op = NULL; /* Not implemented. */ |
| p->set_datalink_op = NULL; /* can't change data link type */ |
| p->getnonblock_op = pcap_getnonblock_fd; |
| p->setnonblock_op = pcap_setnonblock_fd; |
| p->stats_op = pcap_stats_nit; |
| p->close_op = pcap_close_nit; |
| |
| return (p); |
| bad: |
| if (fd >= 0) |
| close(fd); |
| free(p); |
| return (NULL); |
| } |
| |
| int |
| pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) |
| { |
| return (0); |
| } |