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- /* $Id: sendpacket.c 1897 2007-08-25 04:57:38Z aturner $ */
- /*
- * Copyright (c) 2006 Aaron Turner.
- * Copyright (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.com>
- * Copyright (c) 2000 Torsten Landschoff <torsten@debian.org>
- * Sebastian Krahmer <krahmer@cs.uni-potsdam.de>
- * Copyright (c) 1993, 1994, 1995, 1996, 1998
- * 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 the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the names of the copyright owners nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- * 4. 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.''
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
- * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
- * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
- /* sendpacket.[ch] is my attempt to write a universal packet injection
- * API for BPF, libpcap, libnet, and Linux's PF_PACKET. I got sick
- * and tired dealing with libnet bugs and its lack of active maintenence,
- * but unfortunately, libpcap frame injection support is relatively new
- * and not everyone uses Linux, so I decided to support all four as
- * best as possible. If your platform/OS/hardware supports an additional
- * injection method, then by all means add it here (and send me a patch).
- *
- * Anyways, long story short, for now the order of preference is:
- * 1. PF_PACKET
- * 2. BPF
- * 3. libnet
- * 4. pcap_inject()
- * 5. pcap_sendpacket()
- *
- * Right now, one big problem with the pcap_* methods is that libpcap
- * doesn't provide a reliable method of getting the MAC address of
- * an interface (required for tcpbridge).
- * You can use PF_PACKET or BPF to get that, but if your system suports
- * those, might as well inject directly without going through another
- * level of indirection.
- *
- * Please note that some of this code was copied from Libnet 1.1.3
- */
- #include "config.h"
- #include "defines.h"
- #include "common.h"
- #include "sendpacket.h"
- /* Allow users to force the injection method */
- #ifdef FORCE_INJECT_LIBNET
- #undef HAVE_PCAP_INJECT
- #undef HAVE_PCAP_SENDPACKET
- #undef HAVE_BPF
- #elif defined FORCE_INJECT_BPF
- #undef HAVE_LIBNET
- #undef HAVE_PCAP_INJECT
- #undef HAVE_PCAP_SENDPACKET
- #elif defined FORCE_INJECT_PCAP_INJECT
- #undef HAVE_LIBNET
- #undef HAVE_PCAP_SENDPACKET
- #undef HAVE_BPF
- #elif defined FORCE_INJECT_PCAP_SENDPACKET
- #undef HAVE_LIBNET
- #undef HAVE_PCAP_INJECT
- #undef HAVE_BPF
- #endif
- #if (defined HAVE_WINPCAP && defined HAVE_PCAP_INJECT)
- #undef HAVE_PCAP_INJECT /* configure returns true for some odd reason */
- #endif
- #if !defined HAVE_PCAP_INJECT && !defined HAVE_PCAP_SENDPACKET && !defined HAVE_LIBNET && !defined HAVE_PF_PACKET && !defined HAVE_BPF
- #error You need pcap_inject() or pcap_sendpacket() from libpcap, libnet 1.1.3+, Linux's PF_PACKET or *BSD's BPF
- #endif
- #include <string.h>
- #include <errno.h>
- #include <stdarg.h>
- #include <stdio.h>
- #include <sys/types.h>
- #include <sys/time.h>
- #include <sys/ioctl.h>
- #include <sys/file.h>
- #include <sys/socket.h>
- #ifdef HAVE_SYS_PARAM_H
- #include <sys/param.h>
- #endif
- #ifdef HAVE_SYS_SYSCTL_H
- #include <sys/sysctl.h>
- #endif
- #ifdef HAVE_NET_ROUTE_H
- #include <net/route.h>
- #endif
- #include <stdlib.h>
- #include <unistd.h>
- #ifdef HAVE_PF_PACKET
- #include <fcntl.h>
- #include <sys/utsname.h>
- #include <net/if.h>
- #include <netinet/in.h>
- #include <linux/if_ether.h>
- #include <net/if_arp.h>
- #include <netpacket/packet.h>
- #ifndef __GLIBC__
- typedef int socklen_t;
- #endif
- static sendpacket_t *sendpacket_open_pf(const char *, char *);
- static struct tcpr_ether_addr *sendpacket_get_hwaddr_pf(sendpacket_t *);
- static int get_iface_index(int fd, const int8_t *device, char *);
- #endif /* HAVE_PF_PACKET */
- #ifdef HAVE_BPF
- #include <net/bpf.h>
- #include <sys/socket.h>
- #include <net/if.h>
- #include <sys/uio.h>
- #include <net/if_dl.h> // used for get_hwaddr_bpf()
- static sendpacket_t *sendpacket_open_bpf(const char *, char *) _U_;
- static struct tcpr_ether_addr *sendpacket_get_hwaddr_bpf(sendpacket_t *) _U_;
- #endif /* HAVE_BPF */
- #ifdef HAVE_LIBNET
- static sendpacket_t *sendpacket_open_libnet(const char *, char *) _U_;
- static struct tcpr_ether_addr *sendpacket_get_hwaddr_libnet(sendpacket_t *) _U_;
- #endif /* HAVE_LIBNET */
- #if (defined HAVE_PCAP_INJECT || defined HAVE_PCAP_SENDPACKET)
- static sendpacket_t *sendpacket_open_pcap(const char *, char *) _U_;
- static struct tcpr_ether_addr *sendpacket_get_hwaddr_pcap(sendpacket_t *) _U_;
- #endif /* HAVE_PCAP_INJECT || HAVE_PACKET_SENDPACKET */
- static void sendpacket_seterr(sendpacket_t *sp, const char *fmt, ...);
- /* You need to define didsig in your main .c file. Set to 1 if CTRL-C was pressed */
- extern volatile int didsig;
- /**
- * returns number of bytes sent on success or -1 on error
- * Note: it is theoretically possible to get a return code >0 and < len
- * which for most people would be considered an error (the packet wasn't fully sent)
- * so you may want to test for recode != len too.
- */
- int
- sendpacket(sendpacket_t *sp, const u_char *data, size_t len)
- {
- int retcode;
- assert(sp);
- assert(data);
-
- if (len <= 0)
- return -1;
-
- TRY_SEND_AGAIN:
- sp->attempt ++;
- #if defined HAVE_PF_PACKET
- retcode = (int)send(sp->handle.fd, (void *)data, len, 0);
-
- /* out of buffers, silently retry */
- if (retcode < 0 && errno == ENOBUFS && !didsig) {
- sp->retry ++;
- goto TRY_SEND_AGAIN;
- }
- /* some other kind of error */
- else if (retcode < 0) {
- sendpacket_seterr(sp, "Error with pf send(): %s (errno = %d)",
- strerror(errno), errno);
- }
- #elif defined HAVE_BPF
- retcode = write(sp->handle.fd, (void *)data, len);
- if (retcode < 0 && errno == ENOBUFS && !didsig) {
- sp->retry ++;
- goto TRY_SEND_AGAIN;
- } else if (retcode < 0) {
- sendpacket_seterr(sp, "Error with bpf write(): %s (errno = %d)",
- strerror(errno), errno);
- }
- #elif defined HAVE_LIBNET
- retcode = libnet_adv_write_link(sp->handle.lnet, (u_int8_t*)data, (u_int32_t)len);
- if (retcode < 0 && errno == ENOBUFS && !didsig) {
- sp->retry ++;
- goto TRY_SEND_AGAIN;
- } else if (retcode < 0) {
- sendpacket_seterr(sp, "Error with libnet write: %s (errno = %d)",
- libnet_geterror(sp->handle.lnet), errno);
- }
- #elif defined HAVE_PCAP_INJECT
- /*
- * pcap methods don't seem to support ENOBUFS, so we just straight fail
- * is there a better way???
- */
- retcode = pcap_inject(sp->handle.pcap, (void*)data, len);
- if (retcode < 0 && errno == ENOBUFS && !didsig) {
- sp->retry ++;
- goto TRY_SEND_AGAIN;
- } else if (retcode < 0) {
- sendpacket_seterr(sp, "Error with pcap_inject(packet #"
- COUNTER_SPEC "): %s (errno = %d)",
- sp->sent + 1, pcap_geterr(sp->handle.pcap), errno);
- }
- #elif defined HAVE_PCAP_SENDPACKET
- retcode = pcap_sendpacket(sp->handle.pcap, data, (int)len);
- if (retcode < 0 && errno == ENOBUFS && !didsig) {
- sp->retry ++;
- goto TRY_SEND_AGAIN;
- } else if (retcode < 0) {
- sendpacket_seterr(sp, "Error with pcap_sendpacket(packet #"
- COUNTER_SPEC "): %s (errno = %d)",
- sp->sent + 1, pcap_geterr(sp->handle.pcap), errno);
- } else {
- /*
- * pcap_sendpacket returns 0 on success, not the packet length!
- * hence, we have to fix retcode to be more standard on success
- */
- retcode = len;
- }
- #endif
- if (retcode < 0) {
- sp->failed ++;
- } else if (retcode != (int)len) {
- sendpacket_seterr(sp, "Only able to write %d bytes out of %u bytes total",
- retcode, len);
- } else {
- sp->bytes_sent += len;
- sp->sent ++;
- }
- return retcode;
- }
- /**
- * Open the given network device name and returns a sendpacket_t struct
- * pass the error buffer (in case there's a problem) and the direction
- * that this interface represents
- */
- sendpacket_t *
- sendpacket_open(const char *device, char *errbuf, tcpr_dir_t direction)
- {
- sendpacket_t *sp;
- assert(device);
- assert(errbuf);
- #if defined HAVE_PF_PACKET
- sp = sendpacket_open_pf(device, errbuf);
- #elif defined HAVE_BPF
- sp = sendpacket_open_bpf(device, errbuf);
- #elif defined HAVE_LIBNET
- sp = sendpacket_open_libnet(device, errbuf);
- #elif (defined HAVE_PCAP_INJECT || defined HAVE_PCAP_SENDPACKET)
- sp = sendpacket_open_pcap(device, errbuf);
- #endif
- if (sp != NULL) {
- sp->open = 1;
- sp->cache_dir = direction;
- }
- return sp;
- }
- /**
- * Get packet stats for the given sendpacket_t
- */
- char *
- sendpacket_getstat(sendpacket_t *sp)
- {
- static char buf[1024];
-
- assert(sp);
-
- memset(buf, 0, sizeof(buf));
- sprintf(buf, "Statistics for network device: %s\n"
- "\tAttempted packets: " COUNTER_SPEC "\n"
- "\tSuccessful packets: " COUNTER_SPEC "\n"
- "\tFailed packets: " COUNTER_SPEC "\n"
- "\tRetried packets: " COUNTER_SPEC "\n",
- sp->device, sp->attempt, sp->sent, sp->failed, sp->retry);
- return(buf);
- }
- /**
- * close the given sendpacket
- */
- int
- sendpacket_close(sendpacket_t *sp)
- {
- assert(sp);
- safe_free(sp);
- return 0;
- }
- /**
- * returns the Layer 2 address of the interface current
- * open. on error, return NULL
- */
- struct tcpr_ether_addr *
- sendpacket_get_hwaddr(sendpacket_t *sp)
- {
- struct tcpr_ether_addr *addr;
- assert(sp);
-
- /* if we already have our MAC address stored, just return it */
- if (memcmp(&sp->ether, "\x00\x00\x00\x00\x00\x00", ETHER_ADDR_LEN) != 0)
- return &sp->ether;
-
- #if defined HAVE_PF_PACKET
- addr = sendpacket_get_hwaddr_pf(sp);
- #elif defined HAVE_BPF
- addr = sendpacket_get_hwaddr_bpf(sp);
- #elif defined HAVE_LIBNET
- addr = sendpacket_get_hwaddr_libnet(sp);
- #elif (defined HAVE_PCAP_INJECT || defined HAVE_PCAP_SENDPACKET)
- addr = sendpacket_get_hwaddr_pcap(sp);
- #endif
- return addr;
- }
- /**
- * returns the error string
- */
- char *
- sendpacket_geterr(sendpacket_t *sp)
- {
- assert(sp);
- return sp->errbuf;
- }
- /**
- * Set's the error string
- */
- static void
- sendpacket_seterr(sendpacket_t *sp, const char *fmt, ...)
- {
- va_list ap;
-
- assert(sp);
-
- va_start(ap, fmt);
- if (fmt != NULL)
- (void)vsnprintf(sp->errbuf, SENDPACKET_ERRBUF_SIZE, fmt, ap);
- va_end(ap);
-
- sp->errbuf[(SENDPACKET_ERRBUF_SIZE-1)] = '\0'; // be safe
- }
- #if defined HAVE_PCAP_INJECT || defined HAVE_PCAP_SENDPACKET
- /**
- * Inner sendpacket_open() method for using libpcap
- */
- static sendpacket_t *
- sendpacket_open_pcap(const char *device, char *errbuf)
- {
- pcap_t *pcap;
- sendpacket_t *sp;
- /*
- u_int spoof_eth_src = 1;
- int fd;
- */
- assert(device);
- assert(errbuf);
- dbg(1, "sendpacket: using Libpcap");
-
- /* open_pcap_live automatically fills out our errbuf for us */
- if ((pcap = pcap_open_live(device, 0, 0, 0, errbuf)) == NULL)
- return NULL;
-
- sp = (sendpacket_t *)safe_malloc(sizeof(sendpacket_t));
- strlcpy(sp->device, device, sizeof(sp->device));
- sp->handle.pcap = pcap;
- /*
- fd = pcap_get_selectable_fd(pcap);
- if (ioctl(fd, BIOCSHDRCMPLT, &spoof_eth_src) == -1) {
- errx(1, "Unable to enable source MAC spoof support: %s", strerror(errno));
- }
- */
-
- return sp;
- }
- /**
- * Get the hardware MAC address for the given interface using libpcap
- */
- static struct tcpr_ether_addr *
- sendpacket_get_hwaddr_pcap(sendpacket_t *sp)
- {
- assert(sp);
- sendpacket_seterr(sp, "Error: sendpacket_get_hwaddr() not yet supported for pcap injection");
- return NULL;
- }
- #endif /* HAVE_PCAP_INJECT || HAVE_PCAP_SENDPACKET */
- #if defined HAVE_LIBNET
- /**
- * Inner sendpacket_open() method for using libnet
- */
- static sendpacket_t *
- sendpacket_open_libnet(const char *device, char *errbuf)
- {
- libnet_t *lnet;
- sendpacket_t *sp;
-
- assert(device);
- assert(errbuf);
-
- dbg(1, "sendpacket: using Libnet");
-
- if ((lnet = libnet_init(LIBNET_LINK_ADV, device, errbuf)) == NULL)
- return NULL;
- sp = (sendpacket_t *)safe_malloc(sizeof(sendpacket_t));
- strlcpy(sp->device, device, sizeof(sp->device));
- sp->handle.lnet = lnet;
- return sp;
- }
- /**
- * Get the hardware MAC address for the given interface using libnet
- */
- static struct tcpr_ether_addr *
- sendpacket_get_hwaddr_libnet(sendpacket_t *sp)
- {
- struct tcpr_ether_addr *addr;
- assert(sp);
-
- addr = (struct tcpr_ether_addr *)libnet_get_hwaddr(sp->handle.lnet);
-
- if (addr == NULL) {
- sendpacket_seterr(sp, "Error getting hwaddr via libnet: %s", libnet_geterror(sp->handle.lnet));
- return NULL;
- }
-
- memcpy(&sp->ether, addr, sizeof(struct tcpr_ether_addr));
- return(&sp->ether);
- }
- #endif /* HAVE_LIBNET */
- #if defined HAVE_PF_PACKET
- /**
- * Inner sendpacket_open() method for using Linux's PF_PACKET
- */
- static sendpacket_t *
- sendpacket_open_pf(const char *device, char *errbuf)
- {
- int mysocket;
- sendpacket_t *sp;
- struct ifreq ifr;
- struct sockaddr_ll sa;
- int n = 1, err;
- socklen_t errlen = sizeof(err);
- assert(device);
- assert(errbuf);
-
- dbg(1, "sendpacket: using PF_PACKET");
- /* open our socket */
- if ((mysocket = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL))) < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "socket: %s", strerror(errno));
- return NULL;
- }
-
- /* get the interface id for the device */
- if ((sa.sll_ifindex = get_iface_index(mysocket, device, errbuf)) < 0) {
- close(mysocket);
- return NULL;
- }
- /* bind socket to our interface id */
- sa.sll_family = AF_PACKET;
- sa.sll_protocol = htons(ETH_P_ALL);
- if (bind(mysocket, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "bind error: %s", strerror(errno));
- close(mysocket);
- return NULL;
- }
-
- /* check for errors, network down, etc... */
- if (getsockopt(mysocket, SOL_SOCKET, SO_ERROR, &err, &errlen) < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "error opening %s: %s", device,
- strerror(errno));
- close(mysocket);
- return NULL;
- }
-
- if (err > 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "error opening %s: %s", device,
- strerror(err));
- close(mysocket);
- return NULL;
- }
- /* get hardware type for our interface */
- memset(&ifr, 0, sizeof(ifr));
- strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
-
- if (ioctl(mysocket, SIOCGIFHWADDR, &ifr) < 0) {
- close(mysocket);
- sendpacket_seterr(sp, "Error getting hardware type: %s", strerror(errno));
- return NULL;
- }
- /* make sure it's ethernet */
- switch (ifr.ifr_hwaddr.sa_family) {
- case ARPHRD_ETHER:
- break;
- default:
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE,
- "unsupported pysical layer type 0x%x", ifr.ifr_hwaddr.sa_family);
- close(mysocket);
- return NULL;
- }
-
- #ifdef SO_BROADCAST
- /*
- * man 7 socket
- *
- * Set or get the broadcast flag. When enabled, datagram sockets
- * receive packets sent to a broadcast address and they are allowed
- * to send packets to a broadcast address. This option has no
- * effect on stream-oriented sockets.
- */
- if (setsockopt(mysocket, SOL_SOCKET, SO_BROADCAST, &n, sizeof(n)) == -1) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE,
- "SO_BROADCAS: %s\n", strerror(errno));
- close(mysocket);
- return NULL;
- }
- #endif /* SO_BROADCAST */
-
-
- /* prep & return our sp handle */
- sp = (sendpacket_t *)safe_malloc(sizeof(sendpacket_t));
- strlcpy(sp->device, device, sizeof(sp->device));
- sp->handle.fd = mysocket;
-
- return sp;
- }
- /**
- * get the interface index (necessary for sending packets w/ PF_PACKET)
- */
- static int
- get_iface_index(int fd, const int8_t *device, char *errbuf) {
- struct ifreq ifr;
- memset(&ifr, 0, sizeof(ifr));
- strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
- if (ioctl(fd, SIOCGIFINDEX, &ifr) == -1) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "ioctl: %s", strerror(errno));
- return (-1);
- }
- return ifr.ifr_ifindex;
- }
- /**
- * get's the hardware address via Linux's PF packet interface
- */
- struct tcpr_ether_addr *
- sendpacket_get_hwaddr_pf(sendpacket_t *sp)
- {
- struct ifreq ifr;
- int fd;
-
- assert(sp);
-
- if (!sp->open) {
- sendpacket_seterr(sp, "Unable to get hardware address on un-opened sendpacket handle");
- return NULL;
- }
-
- /* create dummy socket for ioctl */
- if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
- sendpacket_seterr(sp, "Unable to open dummy socket for get_hwaddr: %s", strerror(errno));
- return NULL;
- }
- memset(&ifr, 0, sizeof(ifr));
- strlcpy(ifr.ifr_name, sp->device, sizeof(ifr.ifr_name));
-
- if (ioctl(fd, SIOCGIFHWADDR, (int8_t *)&ifr) < 0) {
- close(fd);
- sendpacket_seterr(sp, "Error getting hardware address: %s", strerror(errno));
- return NULL;
- }
-
- memcpy(&sp->ether, &ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
- close(fd);
- return(&sp->ether);
- }
- #endif /* HAVE_PF_PACKET */
- #if defined HAVE_BPF
- /**
- * Inner sendpacket_open() method for using BSD's BPF interface
- */
- static sendpacket_t *
- sendpacket_open_bpf(const char *device, char *errbuf)
- {
- sendpacket_t *sp;
- char bpf_dev[10];
- int dev, mysocket, link_offset, link_type;
- struct ifreq ifr;
- struct bpf_version bv;
- u_int v;
- #if defined(BIOCGHDRCMPLT) && defined(BIOCSHDRCMPLT) && !(__APPLE__)
- u_int spoof_eth_src = 1;
- #endif
-
- assert(device);
- assert(errbuf);
- memset(&ifr, '\0', sizeof(struct ifreq));
-
- dbg(1, "sendpacket: using BPF");
- /* open socket */
- mysocket = -1;
- for (dev = 0; dev <= 9; dev ++) {
- memset(bpf_dev, '\0', sizeof(bpf_dev));
- snprintf(bpf_dev, sizeof(bpf_dev), "/dev/bpf%d", dev);
- if ((mysocket = open(bpf_dev, O_RDWR, 0)) > 0) {
- break;
- }
- }
-
- /* error?? */
- if (mysocket < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE,
- "Unable to open /dev/bpfX: %s", strerror(errno));
- errbuf[SENDPACKET_ERRBUF_SIZE -1] = '\0';
- return NULL;
- }
-
- /* get BPF version */
- if (ioctl(mysocket, BIOCVERSION, (caddr_t)&bv) < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "Unable to get bpf version: %s", strerror(errno));
- return NULL;
- }
- if (bv.bv_major != BPF_MAJOR_VERSION || bv.bv_minor != BPF_MINOR_VERSION) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "Kernel's bpf version is out of date.");
- return NULL;
- }
- /* attach to device */
- strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
- if (ioctl(mysocket, BIOCSETIF, (caddr_t)&ifr) < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "Unable to bind %s to %s: %s",
- bpf_dev, device, strerror(errno));
- return NULL;
- }
-
- /* get datalink type */
- if (ioctl(mysocket, BIOCGDLT, (caddr_t)&v) < 0) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE, "Unable to get datalink type: %s",
- strerror(errno));
- return NULL;
- }
-
- /*
- * NetBSD and FreeBSD BPF have an ioctl for enabling/disabling
- * automatic filling of the link level source address.
- */
- #if defined(BIOCGHDRCMPLT) && defined(BIOCSHDRCMPLT) && !(__APPLE__)
- if (ioctl(mysocket, BIOCSHDRCMPLT, &spoof_eth_src) == -1) {
- snprintf(errbuf, SENDPACKET_ERRBUF_SIZE,
- "Unable to enable spoofing src MAC: %s", strerror(errno));
- return NULL;
- }
- #endif
-
- /* assign link type and offset */
- switch (v) {
- case DLT_SLIP:
- link_offset = 0x10;
- break;
- case DLT_RAW:
- link_offset = 0x0;
- break;
- case DLT_PPP:
- link_offset = 0x04;
- break;
- case DLT_EN10MB:
- default: /* default to Ethernet */
- link_offset = 0xe;
- break;
- }
- #if _BSDI_VERSION - 0 > 199510
- switch (v) {
- case DLT_SLIP:
- v = DLT_SLIP_BSDOS;
- link_offset = 0x10;
- break;
- case DLT_PPP:
- v = DLT_PPP_BSDOS;
- link_offset = 0x04;
- break;
- }
- #endif
-
- link_type = v;
-
- /* allocate our sp handle, and return it */
- sp = (sendpacket_t *)safe_malloc(sizeof(sendpacket_t));
- strlcpy(sp->device, device, sizeof(sp->device));
- sp->handle.fd = mysocket;
- //sp->link_type = link_type;
- //sp->link_offset = link_offset;
-
- return sp;
- }
- /**
- * Get the interface hardware MAC address when using BPF
- */
- struct tcpr_ether_addr *
- sendpacket_get_hwaddr_bpf(sendpacket_t *sp)
- {
- int mib[6];
- size_t len;
- int8_t *buf, *next, *end;
- struct if_msghdr *ifm;
- struct sockaddr_dl *sdl;
- assert(sp);
- mib[0] = CTL_NET;
- mib[1] = AF_ROUTE;
- mib[2] = 0;
- mib[3] = AF_LINK;
- mib[4] = NET_RT_IFLIST;
- mib[5] = 0;
-
- if (sysctl(mib, 6, NULL, &len, NULL, 0) == -1) {
- sendpacket_seterr(sp, "%s(): sysctl(): %s", __func__, strerror(errno));
- return NULL;
- }
-
- buf = (int8_t *)safe_malloc(len);
- if (sysctl(mib, 6, buf, &len, NULL, 0) == -1) {
- sendpacket_seterr(sp, "%s(): sysctl(): %s", __func__, strerror(errno));
- safe_free(buf);
- return NULL;
- }
-
- end = buf + len;
- for (next = buf; next < end; next += ifm->ifm_msglen) {
- ifm = (struct if_msghdr *)next;
- if (ifm->ifm_type == RTM_IFINFO) {
- sdl = (struct sockaddr_dl *)(ifm + 1);
- if (strncmp(&sdl->sdl_data[0], sp->device, sdl->sdl_len) == 0) {
- memcpy(&sp->ether, LLADDR(sdl), ETHER_ADDR_LEN);
- break;
- }
- }
- }
- safe_free(buf);
- return(&sp->ether);
- }
- #endif /* HAVE_BPF */
- /**
- * Get the DLT type of the opened sendpacket
- * Return -1 if we can't figure it out, else return the DLT_ value
- */
- int
- sendpacket_get_dlt(sendpacket_t *sp)
- {
- int dlt;
- #if defined HAVE_BPF
- int rcode;
- if ((rcode = ioctl(sp->handle.fd, BIOCGDLT, &dlt)) < 0) {
- warnx("Unable to get DLT value for BPF device (%s): %s", sp->device, strerror(errno));
- return(-1);
- }
- #elif defined HAVE_PF_PACKET || defined HAVE_LIBNET
- /* use libpcap to get dlt */
- pcap_t *pcap;
- char errbuf[PCAP_ERRBUF_SIZE];
- if ((pcap = pcap_open_live(sp->device, 65535, 0, 0, errbuf)) == NULL) {
- warnx("Unable to get DLT value for %s: %s", sp->device, errbuf);
- return(-1);
- }
- dlt = pcap_datalink(pcap);
- pcap_close(pcap);
- #elif defined HAVE_PCAP_SENDPACKET || defined HAVE_PCAP_INJECT
- dlt = pcap_datalink(sp->handle.pcap);
- #endif
- return dlt;
- }
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