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ip6mr.c
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/*
* Linux IPv6 multicast routing support for BSD pim6sd
* Based on net/ipv4/ipmr.c.
*
* (c) 2004 Mickael Hoerdt, <[email protected]>
* LSIIT Laboratory, Strasbourg, France
* (c) 2004 Jean-Philippe Andriot, <[email protected]>
* 6WIND, Paris, France
* Copyright (C)2007,2008 USAGI/WIDE Project
* YOSHIFUJI Hideaki <[email protected]>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <asm/system.h>
#include <asm/uaccess.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/socket.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/raw.h>
#include <linux/notifier.h>
#include <linux/if_arp.h>
#include <net/checksum.h>
#include <net/netlink.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <linux/mroute6.h>
#include <linux/pim.h>
#include <net/addrconf.h>
#include <linux/netfilter_ipv6.h>
struct sock *mroute6_socket;
/* Big lock, protecting vif table, mrt cache and mroute socket state.
Note that the changes are semaphored via rtnl_lock.
*/
static DEFINE_RWLOCK(mrt_lock);
/*
* Multicast router control variables
*/
static struct mif_device vif6_table[MAXMIFS]; /* Devices */
static int maxvif;
#define MIF_EXISTS(idx) (vif6_table[idx].dev != NULL)
static int mroute_do_assert; /* Set in PIM assert */
#ifdef CONFIG_IPV6_PIMSM_V2
static int mroute_do_pim;
#else
#define mroute_do_pim 0
#endif
static struct mfc6_cache *mfc6_cache_array[MFC6_LINES]; /* Forwarding cache */
static struct mfc6_cache *mfc_unres_queue; /* Queue of unresolved entries */
static atomic_t cache_resolve_queue_len; /* Size of unresolved */
/* Special spinlock for queue of unresolved entries */
static DEFINE_SPINLOCK(mfc_unres_lock);
/* We return to original Alan's scheme. Hash table of resolved
entries is changed only in process context and protected
with weak lock mrt_lock. Queue of unresolved entries is protected
with strong spinlock mfc_unres_lock.
In this case data path is free of exclusive locks at all.
*/
static struct kmem_cache *mrt_cachep __read_mostly;
static int ip6_mr_forward(struct sk_buff *skb, struct mfc6_cache *cache);
static int ip6mr_cache_report(struct sk_buff *pkt, mifi_t mifi, int assert);
static int ip6mr_fill_mroute(struct sk_buff *skb, struct mfc6_cache *c, struct rtmsg *rtm);
#ifdef CONFIG_IPV6_PIMSM_V2
static struct inet6_protocol pim6_protocol;
#endif
static struct timer_list ipmr_expire_timer;
#ifdef CONFIG_PROC_FS
struct ipmr_mfc_iter {
struct mfc6_cache **cache;
int ct;
};
static struct mfc6_cache *ipmr_mfc_seq_idx(struct ipmr_mfc_iter *it, loff_t pos)
{
struct mfc6_cache *mfc;
it->cache = mfc6_cache_array;
read_lock(&mrt_lock);
for (it->ct = 0; it->ct < ARRAY_SIZE(mfc6_cache_array); it->ct++)
for (mfc = mfc6_cache_array[it->ct]; mfc; mfc = mfc->next)
if (pos-- == 0)
return mfc;
read_unlock(&mrt_lock);
it->cache = &mfc_unres_queue;
spin_lock_bh(&mfc_unres_lock);
for (mfc = mfc_unres_queue; mfc; mfc = mfc->next)
if (pos-- == 0)
return mfc;
spin_unlock_bh(&mfc_unres_lock);
it->cache = NULL;
return NULL;
}
/*
* The /proc interfaces to multicast routing /proc/ip6_mr_cache /proc/ip6_mr_vif
*/
struct ipmr_vif_iter {
int ct;
};
static struct mif_device *ip6mr_vif_seq_idx(struct ipmr_vif_iter *iter,
loff_t pos)
{
for (iter->ct = 0; iter->ct < maxvif; ++iter->ct) {
if (!MIF_EXISTS(iter->ct))
continue;
if (pos-- == 0)
return &vif6_table[iter->ct];
}
return NULL;
}
static void *ip6mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(mrt_lock)
{
read_lock(&mrt_lock);
return (*pos ? ip6mr_vif_seq_idx(seq->private, *pos - 1)
: SEQ_START_TOKEN);
}
static void *ip6mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct ipmr_vif_iter *iter = seq->private;
++*pos;
if (v == SEQ_START_TOKEN)
return ip6mr_vif_seq_idx(iter, 0);
while (++iter->ct < maxvif) {
if (!MIF_EXISTS(iter->ct))
continue;
return &vif6_table[iter->ct];
}
return NULL;
}
static void ip6mr_vif_seq_stop(struct seq_file *seq, void *v)
__releases(mrt_lock)
{
read_unlock(&mrt_lock);
}
static int ip6mr_vif_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN) {
seq_puts(seq,
"Interface BytesIn PktsIn BytesOut PktsOut Flags\n");
} else {
const struct mif_device *vif = v;
const char *name = vif->dev ? vif->dev->name : "none";
seq_printf(seq,
"%2td %-10s %8ld %7ld %8ld %7ld %05X\n",
vif - vif6_table,
name, vif->bytes_in, vif->pkt_in,
vif->bytes_out, vif->pkt_out,
vif->flags);
}
return 0;
}
static struct seq_operations ip6mr_vif_seq_ops = {
.start = ip6mr_vif_seq_start,
.next = ip6mr_vif_seq_next,
.stop = ip6mr_vif_seq_stop,
.show = ip6mr_vif_seq_show,
};
static int ip6mr_vif_open(struct inode *inode, struct file *file)
{
return seq_open_private(file, &ip6mr_vif_seq_ops,
sizeof(struct ipmr_vif_iter));
}
static struct file_operations ip6mr_vif_fops = {
.owner = THIS_MODULE,
.open = ip6mr_vif_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static void *ipmr_mfc_seq_start(struct seq_file *seq, loff_t *pos)
{
return (*pos ? ipmr_mfc_seq_idx(seq->private, *pos - 1)
: SEQ_START_TOKEN);
}
static void *ipmr_mfc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct mfc6_cache *mfc = v;
struct ipmr_mfc_iter *it = seq->private;
++*pos;
if (v == SEQ_START_TOKEN)
return ipmr_mfc_seq_idx(seq->private, 0);
if (mfc->next)
return mfc->next;
if (it->cache == &mfc_unres_queue)
goto end_of_list;
BUG_ON(it->cache != mfc6_cache_array);
while (++it->ct < ARRAY_SIZE(mfc6_cache_array)) {
mfc = mfc6_cache_array[it->ct];
if (mfc)
return mfc;
}
/* exhausted cache_array, show unresolved */
read_unlock(&mrt_lock);
it->cache = &mfc_unres_queue;
it->ct = 0;
spin_lock_bh(&mfc_unres_lock);
mfc = mfc_unres_queue;
if (mfc)
return mfc;
end_of_list:
spin_unlock_bh(&mfc_unres_lock);
it->cache = NULL;
return NULL;
}
static void ipmr_mfc_seq_stop(struct seq_file *seq, void *v)
{
struct ipmr_mfc_iter *it = seq->private;
if (it->cache == &mfc_unres_queue)
spin_unlock_bh(&mfc_unres_lock);
else if (it->cache == mfc6_cache_array)
read_unlock(&mrt_lock);
}
static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
{
int n;
if (v == SEQ_START_TOKEN) {
seq_puts(seq,
"Group "
"Origin "
"Iif Pkts Bytes Wrong Oifs\n");
} else {
const struct mfc6_cache *mfc = v;
const struct ipmr_mfc_iter *it = seq->private;
seq_printf(seq,
NIP6_FMT " " NIP6_FMT " %-3d %8ld %8ld %8ld",
NIP6(mfc->mf6c_mcastgrp), NIP6(mfc->mf6c_origin),
mfc->mf6c_parent,
mfc->mfc_un.res.pkt,
mfc->mfc_un.res.bytes,
mfc->mfc_un.res.wrong_if);
if (it->cache != &mfc_unres_queue) {
for (n = mfc->mfc_un.res.minvif;
n < mfc->mfc_un.res.maxvif; n++) {
if (MIF_EXISTS(n) &&
mfc->mfc_un.res.ttls[n] < 255)
seq_printf(seq,
" %2d:%-3d",
n, mfc->mfc_un.res.ttls[n]);
}
}
seq_putc(seq, '\n');
}
return 0;
}
static struct seq_operations ipmr_mfc_seq_ops = {
.start = ipmr_mfc_seq_start,
.next = ipmr_mfc_seq_next,
.stop = ipmr_mfc_seq_stop,
.show = ipmr_mfc_seq_show,
};
static int ipmr_mfc_open(struct inode *inode, struct file *file)
{
return seq_open_private(file, &ipmr_mfc_seq_ops,
sizeof(struct ipmr_mfc_iter));
}
static struct file_operations ip6mr_mfc_fops = {
.owner = THIS_MODULE,
.open = ipmr_mfc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#endif
#ifdef CONFIG_IPV6_PIMSM_V2
static int reg_vif_num = -1;
static int pim6_rcv(struct sk_buff *skb)
{
struct pimreghdr *pim;
struct ipv6hdr *encap;
struct net_device *reg_dev = NULL;
if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
goto drop;
pim = (struct pimreghdr *)skb_transport_header(skb);
if (pim->type != ((PIM_VERSION << 4) | PIM_REGISTER) ||
(pim->flags & PIM_NULL_REGISTER) ||
(ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
csum_fold(skb_checksum(skb, 0, skb->len, 0))))
goto drop;
/* check if the inner packet is destined to mcast group */
encap = (struct ipv6hdr *)(skb_transport_header(skb) +
sizeof(*pim));
if (!ipv6_addr_is_multicast(&encap->daddr) ||
encap->payload_len == 0 ||
ntohs(encap->payload_len) + sizeof(*pim) > skb->len)
goto drop;
read_lock(&mrt_lock);
if (reg_vif_num >= 0)
reg_dev = vif6_table[reg_vif_num].dev;
if (reg_dev)
dev_hold(reg_dev);
read_unlock(&mrt_lock);
if (reg_dev == NULL)
goto drop;
skb->mac_header = skb->network_header;
skb_pull(skb, (u8 *)encap - skb->data);
skb_reset_network_header(skb);
skb->dev = reg_dev;
skb->protocol = htons(ETH_P_IP);
skb->ip_summed = 0;
skb->pkt_type = PACKET_HOST;
dst_release(skb->dst);
reg_dev->stats.rx_bytes += skb->len;
reg_dev->stats.rx_packets++;
skb->dst = NULL;
nf_reset(skb);
netif_rx(skb);
dev_put(reg_dev);
return 0;
drop:
kfree_skb(skb);
return 0;
}
static struct inet6_protocol pim6_protocol = {
.handler = pim6_rcv,
};
/* Service routines creating virtual interfaces: PIMREG */
static int reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
{
read_lock(&mrt_lock);
dev->stats.tx_bytes += skb->len;
dev->stats.tx_packets++;
ip6mr_cache_report(skb, reg_vif_num, MRT6MSG_WHOLEPKT);
read_unlock(&mrt_lock);
kfree_skb(skb);
return 0;
}
static void reg_vif_setup(struct net_device *dev)
{
dev->type = ARPHRD_PIMREG;
dev->mtu = 1500 - sizeof(struct ipv6hdr) - 8;
dev->flags = IFF_NOARP;
dev->hard_start_xmit = reg_vif_xmit;
dev->destructor = free_netdev;
}
static struct net_device *ip6mr_reg_vif(void)
{
struct net_device *dev;
dev = alloc_netdev(0, "pim6reg", reg_vif_setup);
if (dev == NULL)
return NULL;
if (register_netdevice(dev)) {
free_netdev(dev);
return NULL;
}
dev->iflink = 0;
if (dev_open(dev))
goto failure;
dev_hold(dev);
return dev;
failure:
/* allow the register to be completed before unregistering. */
rtnl_unlock();
rtnl_lock();
unregister_netdevice(dev);
return NULL;
}
#endif
/*
* Delete a VIF entry
*/
static int mif6_delete(int vifi)
{
struct mif_device *v;
struct net_device *dev;
if (vifi < 0 || vifi >= maxvif)
return -EADDRNOTAVAIL;
v = &vif6_table[vifi];
write_lock_bh(&mrt_lock);
dev = v->dev;
v->dev = NULL;
if (!dev) {
write_unlock_bh(&mrt_lock);
return -EADDRNOTAVAIL;
}
#ifdef CONFIG_IPV6_PIMSM_V2
if (vifi == reg_vif_num)
reg_vif_num = -1;
#endif
if (vifi + 1 == maxvif) {
int tmp;
for (tmp = vifi - 1; tmp >= 0; tmp--) {
if (MIF_EXISTS(tmp))
break;
}
maxvif = tmp + 1;
}
write_unlock_bh(&mrt_lock);
dev_set_allmulti(dev, -1);
if (v->flags & MIFF_REGISTER)
unregister_netdevice(dev);
dev_put(dev);
return 0;
}
/* Destroy an unresolved cache entry, killing queued skbs
and reporting error to netlink readers.
*/
static void ip6mr_destroy_unres(struct mfc6_cache *c)
{
struct sk_buff *skb;
atomic_dec(&cache_resolve_queue_len);
while((skb = skb_dequeue(&c->mfc_un.unres.unresolved)) != NULL) {
if (ipv6_hdr(skb)->version == 0) {
struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct ipv6hdr));
nlh->nlmsg_type = NLMSG_ERROR;
nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
skb_trim(skb, nlh->nlmsg_len);
((struct nlmsgerr *)NLMSG_DATA(nlh))->error = -ETIMEDOUT;
rtnl_unicast(skb, &init_net, NETLINK_CB(skb).pid);
} else
kfree_skb(skb);
}
kmem_cache_free(mrt_cachep, c);
}
/* Single timer process for all the unresolved queue. */
static void ipmr_do_expire_process(unsigned long dummy)
{
unsigned long now = jiffies;
unsigned long expires = 10 * HZ;
struct mfc6_cache *c, **cp;
cp = &mfc_unres_queue;
while ((c = *cp) != NULL) {
if (time_after(c->mfc_un.unres.expires, now)) {
/* not yet... */
unsigned long interval = c->mfc_un.unres.expires - now;
if (interval < expires)
expires = interval;
cp = &c->next;
continue;
}
*cp = c->next;
ip6mr_destroy_unres(c);
}
if (atomic_read(&cache_resolve_queue_len))
mod_timer(&ipmr_expire_timer, jiffies + expires);
}
static void ipmr_expire_process(unsigned long dummy)
{
if (!spin_trylock(&mfc_unres_lock)) {
mod_timer(&ipmr_expire_timer, jiffies + 1);
return;
}
if (atomic_read(&cache_resolve_queue_len))
ipmr_do_expire_process(dummy);
spin_unlock(&mfc_unres_lock);
}
/* Fill oifs list. It is called under write locked mrt_lock. */
static void ip6mr_update_thresholds(struct mfc6_cache *cache, unsigned char *ttls)
{
int vifi;
cache->mfc_un.res.minvif = MAXMIFS;
cache->mfc_un.res.maxvif = 0;
memset(cache->mfc_un.res.ttls, 255, MAXMIFS);
for (vifi = 0; vifi < maxvif; vifi++) {
if (MIF_EXISTS(vifi) && ttls[vifi] && ttls[vifi] < 255) {
cache->mfc_un.res.ttls[vifi] = ttls[vifi];
if (cache->mfc_un.res.minvif > vifi)
cache->mfc_un.res.minvif = vifi;
if (cache->mfc_un.res.maxvif <= vifi)
cache->mfc_un.res.maxvif = vifi + 1;
}
}
}
static int mif6_add(struct mif6ctl *vifc, int mrtsock)
{
int vifi = vifc->mif6c_mifi;
struct mif_device *v = &vif6_table[vifi];
struct net_device *dev;
int err;
/* Is vif busy ? */
if (MIF_EXISTS(vifi))
return -EADDRINUSE;
switch (vifc->mif6c_flags) {
#ifdef CONFIG_IPV6_PIMSM_V2
case MIFF_REGISTER:
/*
* Special Purpose VIF in PIM
* All the packets will be sent to the daemon
*/
if (reg_vif_num >= 0)
return -EADDRINUSE;
dev = ip6mr_reg_vif();
if (!dev)
return -ENOBUFS;
err = dev_set_allmulti(dev, 1);
if (err) {
unregister_netdevice(dev);
dev_put(dev);
return err;
}
break;
#endif
case 0:
dev = dev_get_by_index(&init_net, vifc->mif6c_pifi);
if (!dev)
return -EADDRNOTAVAIL;
err = dev_set_allmulti(dev, 1);
if (err) {
dev_put(dev);
return err;
}
break;
default:
return -EINVAL;
}
/*
* Fill in the VIF structures
*/
v->rate_limit = vifc->vifc_rate_limit;
v->flags = vifc->mif6c_flags;
if (!mrtsock)
v->flags |= VIFF_STATIC;
v->threshold = vifc->vifc_threshold;
v->bytes_in = 0;
v->bytes_out = 0;
v->pkt_in = 0;
v->pkt_out = 0;
v->link = dev->ifindex;
if (v->flags & MIFF_REGISTER)
v->link = dev->iflink;
/* And finish update writing critical data */
write_lock_bh(&mrt_lock);
v->dev = dev;
#ifdef CONFIG_IPV6_PIMSM_V2
if (v->flags & MIFF_REGISTER)
reg_vif_num = vifi;
#endif
if (vifi + 1 > maxvif)
maxvif = vifi + 1;
write_unlock_bh(&mrt_lock);
return 0;
}
static struct mfc6_cache *ip6mr_cache_find(struct in6_addr *origin, struct in6_addr *mcastgrp)
{
int line = MFC6_HASH(mcastgrp, origin);
struct mfc6_cache *c;
for (c = mfc6_cache_array[line]; c; c = c->next) {
if (ipv6_addr_equal(&c->mf6c_origin, origin) &&
ipv6_addr_equal(&c->mf6c_mcastgrp, mcastgrp))
break;
}
return c;
}
/*
* Allocate a multicast cache entry
*/
static struct mfc6_cache *ip6mr_cache_alloc(void)
{
struct mfc6_cache *c = kmem_cache_alloc(mrt_cachep, GFP_KERNEL);
if (c == NULL)
return NULL;
memset(c, 0, sizeof(*c));
c->mfc_un.res.minvif = MAXMIFS;
return c;
}
static struct mfc6_cache *ip6mr_cache_alloc_unres(void)
{
struct mfc6_cache *c = kmem_cache_alloc(mrt_cachep, GFP_ATOMIC);
if (c == NULL)
return NULL;
memset(c, 0, sizeof(*c));
skb_queue_head_init(&c->mfc_un.unres.unresolved);
c->mfc_un.unres.expires = jiffies + 10 * HZ;
return c;
}
/*
* A cache entry has gone into a resolved state from queued
*/
static void ip6mr_cache_resolve(struct mfc6_cache *uc, struct mfc6_cache *c)
{
struct sk_buff *skb;
/*
* Play the pending entries through our router
*/
while((skb = __skb_dequeue(&uc->mfc_un.unres.unresolved))) {
if (ipv6_hdr(skb)->version == 0) {
int err;
struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct ipv6hdr));
if (ip6mr_fill_mroute(skb, c, NLMSG_DATA(nlh)) > 0) {
nlh->nlmsg_len = skb_tail_pointer(skb) - (u8 *)nlh;
} else {
nlh->nlmsg_type = NLMSG_ERROR;
nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
skb_trim(skb, nlh->nlmsg_len);
((struct nlmsgerr *)NLMSG_DATA(nlh))->error = -EMSGSIZE;
}
err = rtnl_unicast(skb, &init_net, NETLINK_CB(skb).pid);
} else
ip6_mr_forward(skb, c);
}
}
/*
* Bounce a cache query up to pim6sd. We could use netlink for this but pim6sd
* expects the following bizarre scheme.
*
* Called under mrt_lock.
*/
static int ip6mr_cache_report(struct sk_buff *pkt, mifi_t mifi, int assert)
{
struct sk_buff *skb;
struct mrt6msg *msg;
int ret;
#ifdef CONFIG_IPV6_PIMSM_V2
if (assert == MRT6MSG_WHOLEPKT)
skb = skb_realloc_headroom(pkt, -skb_network_offset(pkt)
+sizeof(*msg));
else
#endif
skb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(*msg), GFP_ATOMIC);
if (!skb)
return -ENOBUFS;
/* I suppose that internal messages
* do not require checksums */
skb->ip_summed = CHECKSUM_UNNECESSARY;
#ifdef CONFIG_IPV6_PIMSM_V2
if (assert == MRT6MSG_WHOLEPKT) {
/* Ugly, but we have no choice with this interface.
Duplicate old header, fix length etc.
And all this only to mangle msg->im6_msgtype and
to set msg->im6_mbz to "mbz" :-)
*/
skb_push(skb, -skb_network_offset(pkt));
skb_push(skb, sizeof(*msg));
skb_reset_transport_header(skb);
msg = (struct mrt6msg *)skb_transport_header(skb);
msg->im6_mbz = 0;
msg->im6_msgtype = MRT6MSG_WHOLEPKT;
msg->im6_mif = reg_vif_num;
msg->im6_pad = 0;
ipv6_addr_copy(&msg->im6_src, &ipv6_hdr(pkt)->saddr);
ipv6_addr_copy(&msg->im6_dst, &ipv6_hdr(pkt)->daddr);
skb->ip_summed = CHECKSUM_UNNECESSARY;
} else
#endif
{
/*
* Copy the IP header
*/
skb_put(skb, sizeof(struct ipv6hdr));
skb_reset_network_header(skb);
skb_copy_to_linear_data(skb, ipv6_hdr(pkt), sizeof(struct ipv6hdr));
/*
* Add our header
*/
skb_put(skb, sizeof(*msg));
skb_reset_transport_header(skb);
msg = (struct mrt6msg *)skb_transport_header(skb);
msg->im6_mbz = 0;
msg->im6_msgtype = assert;
msg->im6_mif = mifi;
msg->im6_pad = 0;
ipv6_addr_copy(&msg->im6_src, &ipv6_hdr(pkt)->saddr);
ipv6_addr_copy(&msg->im6_dst, &ipv6_hdr(pkt)->daddr);
skb->dst = dst_clone(pkt->dst);
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb_pull(skb, sizeof(struct ipv6hdr));
}
if (mroute6_socket == NULL) {
kfree_skb(skb);
return -EINVAL;
}
/*
* Deliver to user space multicast routing algorithms
*/
if ((ret = sock_queue_rcv_skb(mroute6_socket, skb)) < 0) {
if (net_ratelimit())
printk(KERN_WARNING "mroute6: pending queue full, dropping entries.\n");
kfree_skb(skb);
}
return ret;
}
/*
* Queue a packet for resolution. It gets locked cache entry!
*/
static int
ip6mr_cache_unresolved(mifi_t mifi, struct sk_buff *skb)
{
int err;
struct mfc6_cache *c;
spin_lock_bh(&mfc_unres_lock);
for (c = mfc_unres_queue; c; c = c->next) {
if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&
ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr))
break;
}
if (c == NULL) {
/*
* Create a new entry if allowable
*/
if (atomic_read(&cache_resolve_queue_len) >= 10 ||
(c = ip6mr_cache_alloc_unres()) == NULL) {
spin_unlock_bh(&mfc_unres_lock);
kfree_skb(skb);
return -ENOBUFS;
}
/*
* Fill in the new cache entry
*/
c->mf6c_parent = -1;
c->mf6c_origin = ipv6_hdr(skb)->saddr;
c->mf6c_mcastgrp = ipv6_hdr(skb)->daddr;
/*
* Reflect first query at pim6sd
*/
if ((err = ip6mr_cache_report(skb, mifi, MRT6MSG_NOCACHE)) < 0) {
/* If the report failed throw the cache entry
out - Brad Parker
*/
spin_unlock_bh(&mfc_unres_lock);
kmem_cache_free(mrt_cachep, c);
kfree_skb(skb);
return err;
}
atomic_inc(&cache_resolve_queue_len);
c->next = mfc_unres_queue;
mfc_unres_queue = c;
ipmr_do_expire_process(1);
}
/*
* See if we can append the packet
*/
if (c->mfc_un.unres.unresolved.qlen > 3) {
kfree_skb(skb);
err = -ENOBUFS;
} else {
skb_queue_tail(&c->mfc_un.unres.unresolved, skb);
err = 0;
}
spin_unlock_bh(&mfc_unres_lock);
return err;
}
/*
* MFC6 cache manipulation by user space
*/
static int ip6mr_mfc_delete(struct mf6cctl *mfc)
{
int line;
struct mfc6_cache *c, **cp;
line = MFC6_HASH(&mfc->mf6cc_mcastgrp.sin6_addr, &mfc->mf6cc_origin.sin6_addr);
for (cp = &mfc6_cache_array[line]; (c = *cp) != NULL; cp = &c->next) {
if (ipv6_addr_equal(&c->mf6c_origin, &mfc->mf6cc_origin.sin6_addr) &&
ipv6_addr_equal(&c->mf6c_mcastgrp, &mfc->mf6cc_mcastgrp.sin6_addr)) {
write_lock_bh(&mrt_lock);
*cp = c->next;
write_unlock_bh(&mrt_lock);
kmem_cache_free(mrt_cachep, c);
return 0;
}
}
return -ENOENT;
}
static int ip6mr_device_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
struct net_device *dev = ptr;
struct mif_device *v;
int ct;
if (!net_eq(dev_net(dev), &init_net))
return NOTIFY_DONE;
if (event != NETDEV_UNREGISTER)
return NOTIFY_DONE;
v = &vif6_table[0];
for (ct = 0; ct < maxvif; ct++, v++) {
if (v->dev == dev)
mif6_delete(ct);
}
return NOTIFY_DONE;
}
static struct notifier_block ip6_mr_notifier = {
.notifier_call = ip6mr_device_event
};
/*
* Setup for IP multicast routing
*/
int __init ip6_mr_init(void)
{
int err;
mrt_cachep = kmem_cache_create("ip6_mrt_cache",
sizeof(struct mfc6_cache),
0, SLAB_HWCACHE_ALIGN,
NULL);
if (!mrt_cachep)
return -ENOMEM;
setup_timer(&ipmr_expire_timer, ipmr_expire_process, 0);
err = register_netdevice_notifier(&ip6_mr_notifier);
if (err)
goto reg_notif_fail;
#ifdef CONFIG_PROC_FS
err = -ENOMEM;
if (!proc_net_fops_create(&init_net, "ip6_mr_vif", 0, &ip6mr_vif_fops))
goto proc_vif_fail;
if (!proc_net_fops_create(&init_net, "ip6_mr_cache",
0, &ip6mr_mfc_fops))
goto proc_cache_fail;
#endif
return 0;
reg_notif_fail:
kmem_cache_destroy(mrt_cachep);
#ifdef CONFIG_PROC_FS
proc_vif_fail:
unregister_netdevice_notifier(&ip6_mr_notifier);
proc_cache_fail:
proc_net_remove(&init_net, "ip6_mr_vif");
#endif
return err;
}
void ip6_mr_cleanup(void)
{
#ifdef CONFIG_PROC_FS
proc_net_remove(&init_net, "ip6_mr_cache");
proc_net_remove(&init_net, "ip6_mr_vif");
#endif