/**********************************************************************
*%FUNCTION: openInterface
*%ARGUMENTS:
* ifname -- name of interface
* type -- Ethernet frame type (0 for any frame type)
* hwaddr -- if non-NULL, set to the hardware address
*%RETURNS:
* A file descriptor for talking with the Ethernet card. Exits on error.
* Note that the Linux version of this routine returns a socket instead.
*%DESCRIPTION:
* Opens a BPF on an interface for all PPPoE traffic (discovery and
* session). If 'type' is 0, uses promiscuous mode to watch any PPPoE
* traffic on this network.
***********************************************************************/
int
openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr)
{
static int fd = -1;
char bpfName[32];
u_int optval;
struct bpf_version bpf_ver;
struct ifreq ifr;
int sock;
int i;
/* BSD only opens one socket for both Discovery and Session packets */
if (fd >= 0) {
return fd;
}
/* Find a free BPF device */
for (i = 0; i < 256; i++) {
sprintf(bpfName, "/dev/bpf%d", i);
if (((fd = open(bpfName, O_RDWR, 0)) >= 0) ||
(errno != EBUSY)) {
break;
}
}
if (fd < 0) {
switch (errno) {
case EACCES: /* permission denied */
{
char buffer[256];
sprintf(buffer, "Cannot open %.32s -- pppoe must be run as root.", bpfName);
rp_fatal(buffer);
}
break;
case EBUSY:
case ENOENT: /* no such file */
if (i == 0) {
rp_fatal("No /dev/bpf* devices (check your kernel configuration for BPF support)");
} else {
rp_fatal("All /dev/bpf* devices are in use");
}
break;
}
fatalSys(bpfName);
}
if ((sock = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0) {
fatalSys("socket");
}
/* Check that the interface is up */
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sock, SIOCGIFFLAGS, &ifr) < 0) {
fatalSys("ioctl(SIOCGIFFLAGS)");
}
if ((ifr.ifr_flags & IFF_UP) == 0) {
char buffer[256];
sprintf(buffer, "Interface %.16s is not up\n", ifname);
rp_fatal(buffer);
}
/* Fill in hardware address and initialize the packet filter rules */
if (hwaddr == NULL) {
rp_fatal("openInterface: no hwaddr arg.");
}
getHWaddr(sock, ifname, hwaddr);
initFilter(fd, type, hwaddr);
/* Sanity check on MTU -- apparently does not work on OpenBSD */
#if !defined(__OpenBSD__)
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sock, SIOCGIFMTU, &ifr) < 0) {
fatalSys("ioctl(SIOCGIFMTU)");
}
if (ifr.ifr_mtu < ETH_DATA_LEN) {
char buffer[256];
sprintf(buffer, "Interface %.16s has MTU of %d -- should be %d. You may have serious connection problems.",
ifname, ifr.ifr_mtu, ETH_DATA_LEN);
printErr(buffer);
}
#endif
/* done with the socket */
if (close(sock) < 0) {
fatalSys("close");
}
/* Check the BPF version number */
if (ioctl(fd, BIOCVERSION, &bpf_ver) < 0) {
fatalSys("ioctl(BIOCVERSION)");
}
if ((bpf_ver.bv_major != BPF_MAJOR_VERSION) ||
(bpf_ver.bv_minor < BPF_MINOR_VERSION)) {
char buffer[256];
sprintf(buffer, "Unsupported BPF version: %d.%d (kernel: %d.%d)",
BPF_MAJOR_VERSION, BPF_MINOR_VERSION,
bpf_ver.bv_major, bpf_ver.bv_minor);
rp_fatal(buffer);
}
/* allocate a receive packet buffer */
if (ioctl(fd, BIOCGBLEN, &bpfLength) < 0) {
fatalSys("ioctl(BIOCGBLEN)");
}
if (!(bpfBuffer = (unsigned char *) malloc(bpfLength))) {
rp_fatal("malloc");
}
/* reads should return as soon as there is a packet available */
optval = 1;
if (ioctl(fd, BIOCIMMEDIATE, &optval) < 0) {
fatalSys("ioctl(BIOCIMMEDIATE)");
}
/* Bind the interface to the filter */
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(fd, BIOCSETIF, &ifr) < 0) {
char buffer[256];
sprintf(buffer, "ioctl(BIOCSETIF) can't select interface %.16s",
ifname);
rp_fatal(buffer);
}
syslog(LOG_INFO, "Interface=%.16s HWaddr=%02X:%02X:%02X:%02X:%02X:%02X Device=%.32s Buffer size=%d",
ifname,
hwaddr[0], hwaddr[1], hwaddr[2],
hwaddr[3], hwaddr[4], hwaddr[5],
bpfName, bpfLength);
return fd;
}
int
openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr)
{
static int fd = -1;
char bpfName[32];
u_int optval;
struct bpf_version bpf_ver;
struct ifreq ifr;
int sock;
int i;
if (fd >= 0) {
return fd;
}
for (i = 0; i < 256; i++) {
sprintf(bpfName, "/dev/bpf%d", i);
if (((fd = open(bpfName, O_RDWR, 0)) >= 0) ||
(errno != EBUSY)) {
break;
}
}
if (fd < 0) {
switch (errno) {
case EACCES:
{
char buffer[256];
sprintf(buffer, "Cannot open %.32s -- pppoe must be run as root.", bpfName);
rp_fatal(buffer);
}
break;
case EBUSY:
case ENOENT:
if (i == 0) {
rp_fatal("No /dev/bpf* devices (check your kernel configuration for BPF support)");
} else {
rp_fatal("All /dev/bpf* devices are in use");
}
break;
}
fatalSys(bpfName);
}
if ((sock = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0) {
fatalSys("socket");
}
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sock, SIOCGIFFLAGS, &ifr) < 0) {
fatalSys("ioctl(SIOCGIFFLAGS)");
}
if ((ifr.ifr_flags & IFF_UP) == 0) {
char buffer[256];
sprintf(buffer, "Interface %.16s is not up", ifname);
rp_fatal(buffer);
}
if (hwaddr == NULL) {
rp_fatal("openInterface: no hwaddr arg.");
}
getHWaddr(sock, ifname, hwaddr);
initFilter(fd, type, hwaddr);
#if !defined(__OpenBSD__)
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(sock, SIOCGIFMTU, &ifr) < 0) {
fatalSys("ioctl(SIOCGIFMTU)");
}
if (ifr.ifr_mtu < ETH_DATA_LEN) {
char buffer[256];
sprintf(buffer, "Interface %.16s has MTU of %d -- should be %d. You may have serious connection problems.",
ifname, ifr.ifr_mtu, ETH_DATA_LEN);
printErr(buffer);
}
#endif
if (close(sock) < 0) {
fatalSys("close");
}
if (ioctl(fd, BIOCVERSION, &bpf_ver) < 0) {
fatalSys("ioctl(BIOCVERSION)");
}
if ((bpf_ver.bv_major != BPF_MAJOR_VERSION) ||
(bpf_ver.bv_minor < BPF_MINOR_VERSION)) {
char buffer[256];
sprintf(buffer, "Unsupported BPF version: %d.%d (kernel: %d.%d)",
BPF_MAJOR_VERSION, BPF_MINOR_VERSION,
bpf_ver.bv_major, bpf_ver.bv_minor);
rp_fatal(buffer);
}
if (ioctl(fd, BIOCGBLEN, &bpfLength) < 0) {
fatalSys("ioctl(BIOCGBLEN)");
}
if (!(bpfBuffer = (unsigned char *) malloc(bpfLength))) {
rp_fatal("malloc");
}
optval = 1;
if (ioctl(fd, BIOCIMMEDIATE, &optval) < 0) {
fatalSys("ioctl(BIOCIMMEDIATE)");
}
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
if (ioctl(fd, BIOCSETIF, &ifr) < 0) {
char buffer[256];
sprintf(buffer, "ioctl(BIOCSETIF) can't select interface %.16s",
ifname);
rp_fatal(buffer);
}
syslog(LOG_INFO, "Interface=%.16s HWaddr=%02X:%02X:%02X:%02X:%02X:%02X Device=%.32s Buffer size=%d",
ifname,
hwaddr[0], hwaddr[1], hwaddr[2],
hwaddr[3], hwaddr[4], hwaddr[5],
bpfName, bpfLength);
return fd;
}
