/*
* Query the kernel to find network interfaces that are multicast-capable
* and install them in the uvifs array.
*/
void config_vifs_from_kernel(void)
{
struct ifreq *ifrp, *ifend;
struct uvif *v;
vifi_t vifi;
uint32_t n;
uint32_t addr, mask, subnet;
short flags;
int num_ifreq = 64;
struct ifconf ifc;
char *newbuf;
total_interfaces = 0; /* The total number of physical interfaces */
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = calloc(ifc.ifc_len, sizeof(char));
while (ifc.ifc_buf) {
if (ioctl(udp_socket, SIOCGIFCONF, (char *)&ifc) < 0)
logit(LOG_ERR, errno, "Failed querying kernel network interfaces");
/*
* If the buffer was large enough to hold all the addresses
* then break out, otherwise increase the buffer size and
* try again.
*
* The only way to know that we definitely had enough space
* is to know that there was enough space for at least one
* more struct ifreq. ???
*/
if ((num_ifreq * sizeof(struct ifreq)) >= ifc.ifc_len + sizeof(struct ifreq))
break;
num_ifreq *= 2;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
newbuf = realloc(ifc.ifc_buf, ifc.ifc_len);
if (newbuf == NULL)
free(ifc.ifc_buf);
ifc.ifc_buf = newbuf;
}
if (ifc.ifc_buf == NULL)
logit(LOG_ERR, 0, "config_vifs_from_kernel() ran out of memory");
ifrp = (struct ifreq *)ifc.ifc_buf;
ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len);
/*
* Loop through all of the interfaces.
*/
for (; ifrp < ifend; ifrp = (struct ifreq *)((char *)ifrp + n)) {
struct ifreq ifr;
memset (&ifr, 0, sizeof (ifr));
#ifdef HAVE_SA_LEN
n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
if (n < sizeof(*ifrp))
n = sizeof(*ifrp);
#else
n = sizeof(*ifrp);
#endif /* HAVE_SA_LEN */
/*
* Ignore any interface for an address family other than IP.
*/
if (ifrp->ifr_addr.sa_family != AF_INET) {
total_interfaces++; /* Eventually may have IP address later */
continue;
}
addr = ((struct sockaddr_in *)&ifrp->ifr_addr)->sin_addr.s_addr;
/*
* Need a template to preserve address info that is
* used below to locate the next entry. (Otherwise,
* SIOCGIFFLAGS stomps over it because the requests
* are returned in a union.)
*/
memcpy(ifr.ifr_name, ifrp->ifr_name, sizeof(ifr.ifr_name));
/*
* Ignore loopback interfaces and interfaces that do not
* support multicast.
*/
if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ifr) < 0)
logit(LOG_ERR, errno, "Failed reading interface flags for phyint %s", ifr.ifr_name);
flags = ifr.ifr_flags;
if ((flags & (IFF_LOOPBACK | IFF_MULTICAST)) != IFF_MULTICAST)
continue;
/*
* Everyone below is a potential vif interface.
* We don't care if it has wrong configuration or not configured
* at all.
*/
total_interfaces++;
/*
* Ignore any interface whose address and mask do not define a
* valid subnet number, or whose address is of the form
* {subnet,0} or {subnet,-1}.
*/
if (ioctl(udp_socket, SIOCGIFNETMASK, (char *)&ifr) < 0) {
if (!(flags & IFF_POINTOPOINT))
logit(LOG_ERR, errno, "Failed reading interface netmask for phyint %s", ifr.ifr_name);
mask = 0xffffffff;
} else {
mask = ((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr.s_addr;
}
subnet = addr & mask;
if ((!inet_valid_subnet(subnet, mask)) || (addr == subnet) || addr == (subnet | ~mask)) {
if (!(inet_valid_host(addr) && ((mask == htonl(0xfffffffe)) || (flags & IFF_POINTOPOINT)))) {
logit(LOG_WARNING, 0, "Ignoring %s, has invalid address %s and/or netmask %s",
ifr.ifr_name, inet_fmt(addr, s1, sizeof(s1)), inet_fmt(mask, s2, sizeof(s2)));
continue;
}
}
/*
* Ignore any interface that is connected to the same subnet as
* one already installed in the uvifs array.
*/
/*
* TODO: XXX: bug or "feature" is to allow only one interface per
* subnet?
*/
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (strcmp(v->uv_name, ifr.ifr_name) == 0) {
logit(LOG_DEBUG, 0, "Ignoring %s (%s on subnet %s) (alias for vif#%u?)",
v->uv_name, inet_fmt(addr, s1, sizeof(s1)), netname(subnet, mask), vifi);
break;
}
/* we don't care about point-to-point links in same subnet */
if (flags & IFF_POINTOPOINT)
continue;
if (v->uv_flags & VIFF_POINT_TO_POINT)
continue;
#if 0
/*
* TODO: to allow different interfaces belong to
* overlapping subnet addresses, use this version instead
*/
if (((addr & mask ) == v->uv_subnet) && (v->uv_subnetmask == mask)) {
logit(LOG_WARNING, 0, "Ignoring %s, same subnet as %s", ifr.ifr_name, v->uv_name);
break;
}
#else
if ((addr & v->uv_subnetmask) == v->uv_subnet || (v->uv_subnet & mask) == subnet) {
logit(LOG_WARNING, 0, "Ignoring %s, same subnet as %s", ifr.ifr_name, v->uv_name);
break;
}
#endif /* 0 */
}
if (vifi != numvifs)
continue;
/*
* If there is room in the uvifs array, install this interface.
*/
if (numvifs == MAXVIFS) {
logit(LOG_WARNING, 0, "Too many vifs, ignoring %s", ifr.ifr_name);
continue;
}
v = &uvifs[numvifs];
zero_vif(v, FALSE);
v->uv_lcl_addr = addr;
v->uv_subnet = subnet;
v->uv_subnetmask = mask;
if (mask != htonl(0xfffffffe))
v->uv_subnetbcast = subnet | ~mask;
else
v->uv_subnetbcast = 0xffffffff;
strlcpy(v->uv_name, ifr.ifr_name, IFNAMSIZ);
/*
* Figure out MTU of interface, needed as a seed value when
* fragmenting PIM register messages. We should really do
* a PMTU check on initial PIM register send to a new RP...
*/
if (ioctl(udp_socket, SIOCGIFMTU, &ifr) < 0)
v->uv_mtu = 1500;
else
v->uv_mtu = ifr.ifr_mtu;
if (flags & IFF_POINTOPOINT) {
v->uv_flags |= (VIFF_REXMIT_PRUNES | VIFF_POINT_TO_POINT);
if (ioctl(udp_socket, SIOCGIFDSTADDR, (char *)&ifr) < 0)
logit(LOG_ERR, errno, "Failed reading point-to-point address for %s", v->uv_name);
else
v->uv_rmt_addr = ((struct sockaddr_in *)(&ifr.ifr_dstaddr))->sin_addr.s_addr;
} else if (mask == htonl(0xfffffffe)) {
/*
* Handle RFC 3021 /31 netmasks as point-to-point links
*/
v->uv_flags |= (VIFF_REXMIT_PRUNES | VIFF_POINT_TO_POINT);
if (addr == subnet)
v->uv_rmt_addr = addr + htonl(1);
else
v->uv_rmt_addr = subnet;
}
#ifdef __linux__
{
struct ifreq ifridx;
memset(&ifridx, 0, sizeof(ifridx));
strlcpy(ifridx.ifr_name,v->uv_name, IFNAMSIZ);
if (ioctl(udp_socket, SIOGIFINDEX, (char *) &ifridx) < 0)
logit(LOG_ERR, errno, "Failed reading interface index for %s", ifridx.ifr_name);
v->uv_ifindex = ifridx.ifr_ifindex;
}
if (v->uv_flags & VIFF_POINT_TO_POINT) {
logit(LOG_INFO, 0, "Installing %s (%s -> %s) as vif #%u-%d - rate %d",
v->uv_name, inet_fmt(addr, s1, sizeof(s1)), inet_fmt(v->uv_rmt_addr, s2, sizeof(s2)),
numvifs, v->uv_ifindex, v->uv_rate_limit);
} else {
logit(LOG_INFO, 0, "Installing %s (%s on subnet %s) as vif #%u-%d - rate %d",
v->uv_name, inet_fmt(addr, s1, sizeof(s1)), netname(subnet, mask),
numvifs, v->uv_ifindex, v->uv_rate_limit);
}
#else /* !__linux__ */
if (v->uv_flags & VIFF_POINT_TO_POINT) {
logit(LOG_INFO, 0, "Installing %s (%s -> %s) as vif #%u - rate=%d",
v->uv_name, inet_fmt(addr, s1, sizeof(s1)), inet_fmt(v->uv_rmt_addr, s2, sizeof(s2)),
numvifs, v->uv_rate_limit);
} else {
logit(LOG_INFO, 0, "Installing %s (%s on subnet %s) as vif #%u - rate %d",
v->uv_name, inet_fmt(addr, s1, sizeof(s1)), netname(subnet, mask),
numvifs, v->uv_rate_limit);
}
#endif /* __linux__ */
++numvifs;
/*
* If the interface is not yet up, set the vifs_down flag to
* remind us to check again later.
*/
if (!(flags & IFF_UP)) {
v->uv_flags |= VIFF_DOWN;
vifs_down = TRUE;
}
}
}
/*
* Query the kernel to find network interfaces that are multicast-capable
* and install them in the uvifs array.
*/
void
config_vifs_from_kernel(void)
{
struct ifreq *ifrp, *ifend;
struct uvif *v;
vifi_t vifi;
int n;
u_int32 addr, mask, subnet;
short flags;
int num_ifreq = 32;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = malloc(ifc.ifc_len);
while (ifc.ifc_buf) {
if (ioctl(udp_socket, SIOCGIFCONF, (char *)&ifc) < 0)
dolog(LOG_ERR, errno, "ioctl SIOCGIFCONF");
/*
* If the buffer was large enough to hold all the addresses
* then break out, otherwise increase the buffer size and
* try again.
*
* The only way to know that we definitely had enough space
* is to know that there was enough space for at least one
* more struct ifreq. ???
*/
if ((num_ifreq * sizeof(struct ifreq)) >=
ifc.ifc_len + sizeof(struct ifreq))
break;
num_ifreq *= 2;
ifc.ifc_len = num_ifreq * sizeof(struct ifreq);
ifc.ifc_buf = realloc(ifc.ifc_buf, ifc.ifc_len);
}
if (ifc.ifc_buf == NULL)
dolog(LOG_ERR, 0, "config_vifs_from_kernel: ran out of memory");
ifrp = (struct ifreq *)ifc.ifc_buf;
ifend = (struct ifreq *)(ifc.ifc_buf + ifc.ifc_len);
/*
* Loop through all of the interfaces.
*/
for (; ifrp < ifend; ifrp = (struct ifreq *)((char *)ifrp + n)) {
struct ifreq ifr;
#ifdef HAVE_SA_LEN
n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
if (n < sizeof(*ifrp))
n = sizeof(*ifrp);
#else
n = sizeof(*ifrp);
#endif
/*
* Ignore any interface for an address family other than IP.
*/
if (ifrp->ifr_addr.sa_family != AF_INET)
continue;
addr = ((struct sockaddr_in *)&ifrp->ifr_addr)->sin_addr.s_addr;
/*
* Need a template to preserve address info that is
* used below to locate the next entry. (Otherwise,
* SIOCGIFFLAGS stomps over it because the requests
* are returned in a union.)
*/
bcopy(ifrp->ifr_name, ifr.ifr_name, sizeof(ifr.ifr_name));
/*
* Ignore loopback interfaces and interfaces that do not support
* multicast.
*/
if (ioctl(udp_socket, SIOCGIFFLAGS, (char *)&ifr) < 0)
dolog(LOG_ERR, errno, "ioctl SIOCGIFFLAGS for %s", ifr.ifr_name);
flags = ifr.ifr_flags;
if ((flags & (IFF_LOOPBACK|IFF_MULTICAST)) != IFF_MULTICAST) continue;
/*
* Ignore any interface whose address and mask do not define a
* valid subnet number, or whose address is of the form {subnet,0}
* or {subnet,-1}.
*/
if (ioctl(udp_socket, SIOCGIFNETMASK, (char *)&ifr) < 0)
dolog(LOG_ERR, errno, "ioctl SIOCGIFNETMASK for %s", ifr.ifr_name);
mask = ((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr.s_addr;
subnet = addr & mask;
if (!inet_valid_subnet(subnet, mask) ||
addr == subnet ||
addr == (subnet | ~mask)) {
dolog(LOG_WARNING, 0,
"ignoring %s, has invalid address (%s) and/or mask (%s)",
ifr.ifr_name, inet_fmt(addr, s1), inet_fmt(mask, s2));
continue;
}
/*
* Ignore any interface that is connected to the same subnet as
* one already installed in the uvifs array.
*/
for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
if (strcmp(v->uv_name, ifr.ifr_name) == 0) {
dolog(LOG_DEBUG, 0, "skipping %s (%s on subnet %s) (alias for vif#%u?)",
v->uv_name, inet_fmt(addr, s1),
inet_fmts(subnet, mask, s2), vifi);
break;
}
if ((addr & v->uv_subnetmask) == v->uv_subnet ||
(v->uv_subnet & mask) == subnet) {
dolog(LOG_WARNING, 0, "ignoring %s, same subnet as %s",
ifr.ifr_name, v->uv_name);
break;
}
}
if (vifi != numvifs) continue;
/*
* If there is room in the uvifs array, install this interface.
*/
if (numvifs == MAXVIFS) {
dolog(LOG_WARNING, 0, "too many vifs, ignoring %s", ifr.ifr_name);
continue;
}
v = &uvifs[numvifs];
zero_vif(v, 0);
v->uv_lcl_addr = addr;
v->uv_subnet = subnet;
v->uv_subnetmask = mask;
v->uv_subnetbcast = subnet | ~mask;
strncpy(v->uv_name, ifr.ifr_name, IFNAMSIZ);
v->uv_name[IFNAMSIZ-1] = '\0';
if (flags & IFF_POINTOPOINT)
v->uv_flags |= VIFF_REXMIT_PRUNES;
dolog(LOG_INFO,0,"installing %s (%s on subnet %s) as vif #%u - rate=%d",
v->uv_name, inet_fmt(addr, s1), inet_fmts(subnet, mask, s2),
numvifs, v->uv_rate_limit);
++numvifs;
/*
* If the interface is not yet up, set the vifs_down flag to
* remind us to check again later.
*/
if (!(flags & IFF_UP)) {
v->uv_flags |= VIFF_DOWN;
vifs_down = TRUE;
}
}
}