linux-stable/drivers/net/amt.c
Taehee Yoo bec161add3 amt: do not use overwrapped cb area
amt driver uses skb->cb for storing tunnel information.
This job is worked before TC layer and then amt driver load tunnel info
from skb->cb after TC layer.
So, its cb area should not be overwrapped with CB area used by TC.
In order to not use cb area used by TC, it skips the biggest cb
structure used by TC, which was qdisc_skb_cb.
But it's not anymore.
Currently, biggest structure of TC's CB is tc_skb_cb.
So, it should skip size of tc_skb_cb instead of qdisc_skb_cb.

Fixes: ec624fe740 ("net/sched: Extend qdisc control block with tc control block")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20240107144241.4169520-1-ap420073@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-11 16:55:17 -08:00

3454 lines
89 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* Copyright (c) 2021 Taehee Yoo <ap420073@gmail.com> */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/udp.h>
#include <linux/jhash.h>
#include <linux/if_tunnel.h>
#include <linux/net.h>
#include <linux/igmp.h>
#include <linux/workqueue.h>
#include <net/pkt_sched.h>
#include <net/net_namespace.h>
#include <net/ip.h>
#include <net/udp.h>
#include <net/udp_tunnel.h>
#include <net/icmp.h>
#include <net/mld.h>
#include <net/amt.h>
#include <uapi/linux/amt.h>
#include <linux/security.h>
#include <net/gro_cells.h>
#include <net/ipv6.h>
#include <net/if_inet6.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include <net/inet_common.h>
#include <net/ip6_checksum.h>
static struct workqueue_struct *amt_wq;
static HLIST_HEAD(source_gc_list);
/* Lock for source_gc_list */
static spinlock_t source_gc_lock;
static struct delayed_work source_gc_wq;
static char *status_str[] = {
"AMT_STATUS_INIT",
"AMT_STATUS_SENT_DISCOVERY",
"AMT_STATUS_RECEIVED_DISCOVERY",
"AMT_STATUS_SENT_ADVERTISEMENT",
"AMT_STATUS_RECEIVED_ADVERTISEMENT",
"AMT_STATUS_SENT_REQUEST",
"AMT_STATUS_RECEIVED_REQUEST",
"AMT_STATUS_SENT_QUERY",
"AMT_STATUS_RECEIVED_QUERY",
"AMT_STATUS_SENT_UPDATE",
"AMT_STATUS_RECEIVED_UPDATE",
};
static char *type_str[] = {
"", /* Type 0 is not defined */
"AMT_MSG_DISCOVERY",
"AMT_MSG_ADVERTISEMENT",
"AMT_MSG_REQUEST",
"AMT_MSG_MEMBERSHIP_QUERY",
"AMT_MSG_MEMBERSHIP_UPDATE",
"AMT_MSG_MULTICAST_DATA",
"AMT_MSG_TEARDOWN",
};
static char *action_str[] = {
"AMT_ACT_GMI",
"AMT_ACT_GMI_ZERO",
"AMT_ACT_GT",
"AMT_ACT_STATUS_FWD_NEW",
"AMT_ACT_STATUS_D_FWD_NEW",
"AMT_ACT_STATUS_NONE_NEW",
};
static struct igmpv3_grec igmpv3_zero_grec;
#if IS_ENABLED(CONFIG_IPV6)
#define MLD2_ALL_NODE_INIT { { { 0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01 } } }
static struct in6_addr mld2_all_node = MLD2_ALL_NODE_INIT;
static struct mld2_grec mldv2_zero_grec;
#endif
static struct amt_skb_cb *amt_skb_cb(struct sk_buff *skb)
{
BUILD_BUG_ON(sizeof(struct amt_skb_cb) + sizeof(struct tc_skb_cb) >
sizeof_field(struct sk_buff, cb));
return (struct amt_skb_cb *)((void *)skb->cb +
sizeof(struct tc_skb_cb));
}
static void __amt_source_gc_work(void)
{
struct amt_source_node *snode;
struct hlist_head gc_list;
struct hlist_node *t;
spin_lock_bh(&source_gc_lock);
hlist_move_list(&source_gc_list, &gc_list);
spin_unlock_bh(&source_gc_lock);
hlist_for_each_entry_safe(snode, t, &gc_list, node) {
hlist_del_rcu(&snode->node);
kfree_rcu(snode, rcu);
}
}
static void amt_source_gc_work(struct work_struct *work)
{
__amt_source_gc_work();
spin_lock_bh(&source_gc_lock);
mod_delayed_work(amt_wq, &source_gc_wq,
msecs_to_jiffies(AMT_GC_INTERVAL));
spin_unlock_bh(&source_gc_lock);
}
static bool amt_addr_equal(union amt_addr *a, union amt_addr *b)
{
return !memcmp(a, b, sizeof(union amt_addr));
}
static u32 amt_source_hash(struct amt_tunnel_list *tunnel, union amt_addr *src)
{
u32 hash = jhash(src, sizeof(*src), tunnel->amt->hash_seed);
return reciprocal_scale(hash, tunnel->amt->hash_buckets);
}
static bool amt_status_filter(struct amt_source_node *snode,
enum amt_filter filter)
{
bool rc = false;
switch (filter) {
case AMT_FILTER_FWD:
if (snode->status == AMT_SOURCE_STATUS_FWD &&
snode->flags == AMT_SOURCE_OLD)
rc = true;
break;
case AMT_FILTER_D_FWD:
if (snode->status == AMT_SOURCE_STATUS_D_FWD &&
snode->flags == AMT_SOURCE_OLD)
rc = true;
break;
case AMT_FILTER_FWD_NEW:
if (snode->status == AMT_SOURCE_STATUS_FWD &&
snode->flags == AMT_SOURCE_NEW)
rc = true;
break;
case AMT_FILTER_D_FWD_NEW:
if (snode->status == AMT_SOURCE_STATUS_D_FWD &&
snode->flags == AMT_SOURCE_NEW)
rc = true;
break;
case AMT_FILTER_ALL:
rc = true;
break;
case AMT_FILTER_NONE_NEW:
if (snode->status == AMT_SOURCE_STATUS_NONE &&
snode->flags == AMT_SOURCE_NEW)
rc = true;
break;
case AMT_FILTER_BOTH:
if ((snode->status == AMT_SOURCE_STATUS_D_FWD ||
snode->status == AMT_SOURCE_STATUS_FWD) &&
snode->flags == AMT_SOURCE_OLD)
rc = true;
break;
case AMT_FILTER_BOTH_NEW:
if ((snode->status == AMT_SOURCE_STATUS_D_FWD ||
snode->status == AMT_SOURCE_STATUS_FWD) &&
snode->flags == AMT_SOURCE_NEW)
rc = true;
break;
default:
WARN_ON_ONCE(1);
break;
}
return rc;
}
static struct amt_source_node *amt_lookup_src(struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
enum amt_filter filter,
union amt_addr *src)
{
u32 hash = amt_source_hash(tunnel, src);
struct amt_source_node *snode;
hlist_for_each_entry_rcu(snode, &gnode->sources[hash], node)
if (amt_status_filter(snode, filter) &&
amt_addr_equal(&snode->source_addr, src))
return snode;
return NULL;
}
static u32 amt_group_hash(struct amt_tunnel_list *tunnel, union amt_addr *group)
{
u32 hash = jhash(group, sizeof(*group), tunnel->amt->hash_seed);
return reciprocal_scale(hash, tunnel->amt->hash_buckets);
}
static struct amt_group_node *amt_lookup_group(struct amt_tunnel_list *tunnel,
union amt_addr *group,
union amt_addr *host,
bool v6)
{
u32 hash = amt_group_hash(tunnel, group);
struct amt_group_node *gnode;
hlist_for_each_entry_rcu(gnode, &tunnel->groups[hash], node) {
if (amt_addr_equal(&gnode->group_addr, group) &&
amt_addr_equal(&gnode->host_addr, host) &&
gnode->v6 == v6)
return gnode;
}
return NULL;
}
static void amt_destroy_source(struct amt_source_node *snode)
{
struct amt_group_node *gnode = snode->gnode;
struct amt_tunnel_list *tunnel;
tunnel = gnode->tunnel_list;
if (!gnode->v6) {
netdev_dbg(snode->gnode->amt->dev,
"Delete source %pI4 from %pI4\n",
&snode->source_addr.ip4,
&gnode->group_addr.ip4);
#if IS_ENABLED(CONFIG_IPV6)
} else {
netdev_dbg(snode->gnode->amt->dev,
"Delete source %pI6 from %pI6\n",
&snode->source_addr.ip6,
&gnode->group_addr.ip6);
#endif
}
cancel_delayed_work(&snode->source_timer);
hlist_del_init_rcu(&snode->node);
tunnel->nr_sources--;
gnode->nr_sources--;
spin_lock_bh(&source_gc_lock);
hlist_add_head_rcu(&snode->node, &source_gc_list);
spin_unlock_bh(&source_gc_lock);
}
static void amt_del_group(struct amt_dev *amt, struct amt_group_node *gnode)
{
struct amt_source_node *snode;
struct hlist_node *t;
int i;
if (cancel_delayed_work(&gnode->group_timer))
dev_put(amt->dev);
hlist_del_rcu(&gnode->node);
gnode->tunnel_list->nr_groups--;
if (!gnode->v6)
netdev_dbg(amt->dev, "Leave group %pI4\n",
&gnode->group_addr.ip4);
#if IS_ENABLED(CONFIG_IPV6)
else
netdev_dbg(amt->dev, "Leave group %pI6\n",
&gnode->group_addr.ip6);
#endif
for (i = 0; i < amt->hash_buckets; i++)
hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node)
amt_destroy_source(snode);
/* tunnel->lock was acquired outside of amt_del_group()
* But rcu_read_lock() was acquired too so It's safe.
*/
kfree_rcu(gnode, rcu);
}
/* If a source timer expires with a router filter-mode for the group of
* INCLUDE, the router concludes that traffic from this particular
* source is no longer desired on the attached network, and deletes the
* associated source record.
*/
static void amt_source_work(struct work_struct *work)
{
struct amt_source_node *snode = container_of(to_delayed_work(work),
struct amt_source_node,
source_timer);
struct amt_group_node *gnode = snode->gnode;
struct amt_dev *amt = gnode->amt;
struct amt_tunnel_list *tunnel;
tunnel = gnode->tunnel_list;
spin_lock_bh(&tunnel->lock);
rcu_read_lock();
if (gnode->filter_mode == MCAST_INCLUDE) {
amt_destroy_source(snode);
if (!gnode->nr_sources)
amt_del_group(amt, gnode);
} else {
/* When a router filter-mode for a group is EXCLUDE,
* source records are only deleted when the group timer expires
*/
snode->status = AMT_SOURCE_STATUS_D_FWD;
}
rcu_read_unlock();
spin_unlock_bh(&tunnel->lock);
}
static void amt_act_src(struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
struct amt_source_node *snode,
enum amt_act act)
{
struct amt_dev *amt = tunnel->amt;
switch (act) {
case AMT_ACT_GMI:
mod_delayed_work(amt_wq, &snode->source_timer,
msecs_to_jiffies(amt_gmi(amt)));
break;
case AMT_ACT_GMI_ZERO:
cancel_delayed_work(&snode->source_timer);
break;
case AMT_ACT_GT:
mod_delayed_work(amt_wq, &snode->source_timer,
gnode->group_timer.timer.expires);
break;
case AMT_ACT_STATUS_FWD_NEW:
snode->status = AMT_SOURCE_STATUS_FWD;
snode->flags = AMT_SOURCE_NEW;
break;
case AMT_ACT_STATUS_D_FWD_NEW:
snode->status = AMT_SOURCE_STATUS_D_FWD;
snode->flags = AMT_SOURCE_NEW;
break;
case AMT_ACT_STATUS_NONE_NEW:
cancel_delayed_work(&snode->source_timer);
snode->status = AMT_SOURCE_STATUS_NONE;
snode->flags = AMT_SOURCE_NEW;
break;
default:
WARN_ON_ONCE(1);
return;
}
if (!gnode->v6)
netdev_dbg(amt->dev, "Source %pI4 from %pI4 Acted %s\n",
&snode->source_addr.ip4,
&gnode->group_addr.ip4,
action_str[act]);
#if IS_ENABLED(CONFIG_IPV6)
else
netdev_dbg(amt->dev, "Source %pI6 from %pI6 Acted %s\n",
&snode->source_addr.ip6,
&gnode->group_addr.ip6,
action_str[act]);
#endif
}
static struct amt_source_node *amt_alloc_snode(struct amt_group_node *gnode,
union amt_addr *src)
{
struct amt_source_node *snode;
snode = kzalloc(sizeof(*snode), GFP_ATOMIC);
if (!snode)
return NULL;
memcpy(&snode->source_addr, src, sizeof(union amt_addr));
snode->gnode = gnode;
snode->status = AMT_SOURCE_STATUS_NONE;
snode->flags = AMT_SOURCE_NEW;
INIT_HLIST_NODE(&snode->node);
INIT_DELAYED_WORK(&snode->source_timer, amt_source_work);
return snode;
}
/* RFC 3810 - 7.2.2. Definition of Filter Timers
*
* Router Mode Filter Timer Actions/Comments
* ----------- ----------------- ----------------
*
* INCLUDE Not Used All listeners in
* INCLUDE mode.
*
* EXCLUDE Timer > 0 At least one listener
* in EXCLUDE mode.
*
* EXCLUDE Timer == 0 No more listeners in
* EXCLUDE mode for the
* multicast address.
* If the Requested List
* is empty, delete
* Multicast Address
* Record. If not, switch
* to INCLUDE filter mode;
* the sources in the
* Requested List are
* moved to the Include
* List, and the Exclude
* List is deleted.
*/
static void amt_group_work(struct work_struct *work)
{
struct amt_group_node *gnode = container_of(to_delayed_work(work),
struct amt_group_node,
group_timer);
struct amt_tunnel_list *tunnel = gnode->tunnel_list;
struct amt_dev *amt = gnode->amt;
struct amt_source_node *snode;
bool delete_group = true;
struct hlist_node *t;
int i, buckets;
buckets = amt->hash_buckets;
spin_lock_bh(&tunnel->lock);
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Not Used */
spin_unlock_bh(&tunnel->lock);
goto out;
}
rcu_read_lock();
for (i = 0; i < buckets; i++) {
hlist_for_each_entry_safe(snode, t,
&gnode->sources[i], node) {
if (!delayed_work_pending(&snode->source_timer) ||
snode->status == AMT_SOURCE_STATUS_D_FWD) {
amt_destroy_source(snode);
} else {
delete_group = false;
snode->status = AMT_SOURCE_STATUS_FWD;
}
}
}
if (delete_group)
amt_del_group(amt, gnode);
else
gnode->filter_mode = MCAST_INCLUDE;
rcu_read_unlock();
spin_unlock_bh(&tunnel->lock);
out:
dev_put(amt->dev);
}
/* Non-existent group is created as INCLUDE {empty}:
*
* RFC 3376 - 5.1. Action on Change of Interface State
*
* If no interface state existed for that multicast address before
* the change (i.e., the change consisted of creating a new
* per-interface record), or if no state exists after the change
* (i.e., the change consisted of deleting a per-interface record),
* then the "non-existent" state is considered to have a filter mode
* of INCLUDE and an empty source list.
*/
static struct amt_group_node *amt_add_group(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
union amt_addr *group,
union amt_addr *host,
bool v6)
{
struct amt_group_node *gnode;
u32 hash;
int i;
if (tunnel->nr_groups >= amt->max_groups)
return ERR_PTR(-ENOSPC);
gnode = kzalloc(sizeof(*gnode) +
(sizeof(struct hlist_head) * amt->hash_buckets),
GFP_ATOMIC);
if (unlikely(!gnode))
return ERR_PTR(-ENOMEM);
gnode->amt = amt;
gnode->group_addr = *group;
gnode->host_addr = *host;
gnode->v6 = v6;
gnode->tunnel_list = tunnel;
gnode->filter_mode = MCAST_INCLUDE;
INIT_HLIST_NODE(&gnode->node);
INIT_DELAYED_WORK(&gnode->group_timer, amt_group_work);
for (i = 0; i < amt->hash_buckets; i++)
INIT_HLIST_HEAD(&gnode->sources[i]);
hash = amt_group_hash(tunnel, group);
hlist_add_head_rcu(&gnode->node, &tunnel->groups[hash]);
tunnel->nr_groups++;
if (!gnode->v6)
netdev_dbg(amt->dev, "Join group %pI4\n",
&gnode->group_addr.ip4);
#if IS_ENABLED(CONFIG_IPV6)
else
netdev_dbg(amt->dev, "Join group %pI6\n",
&gnode->group_addr.ip6);
#endif
return gnode;
}
static struct sk_buff *amt_build_igmp_gq(struct amt_dev *amt)
{
u8 ra[AMT_IPHDR_OPTS] = { IPOPT_RA, 4, 0, 0 };
int hlen = LL_RESERVED_SPACE(amt->dev);
int tlen = amt->dev->needed_tailroom;
struct igmpv3_query *ihv3;
void *csum_start = NULL;
__sum16 *csum = NULL;
struct sk_buff *skb;
struct ethhdr *eth;
struct iphdr *iph;
unsigned int len;
int offset;
len = hlen + tlen + sizeof(*iph) + AMT_IPHDR_OPTS + sizeof(*ihv3);
skb = netdev_alloc_skb_ip_align(amt->dev, len);
if (!skb)
return NULL;
skb_reserve(skb, hlen);
skb_push(skb, sizeof(*eth));
skb->protocol = htons(ETH_P_IP);
skb_reset_mac_header(skb);
skb->priority = TC_PRIO_CONTROL;
skb_put(skb, sizeof(*iph));
skb_put_data(skb, ra, sizeof(ra));
skb_put(skb, sizeof(*ihv3));
skb_pull(skb, sizeof(*eth));
skb_reset_network_header(skb);
iph = ip_hdr(skb);
iph->version = 4;
iph->ihl = (sizeof(struct iphdr) + AMT_IPHDR_OPTS) >> 2;
iph->tos = AMT_TOS;
iph->tot_len = htons(sizeof(*iph) + AMT_IPHDR_OPTS + sizeof(*ihv3));
iph->frag_off = htons(IP_DF);
iph->ttl = 1;
iph->id = 0;
iph->protocol = IPPROTO_IGMP;
iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
iph->saddr = htonl(INADDR_ANY);
ip_send_check(iph);
eth = eth_hdr(skb);
ether_addr_copy(eth->h_source, amt->dev->dev_addr);
ip_eth_mc_map(htonl(INADDR_ALLHOSTS_GROUP), eth->h_dest);
eth->h_proto = htons(ETH_P_IP);
ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
skb_reset_transport_header(skb);
ihv3->type = IGMP_HOST_MEMBERSHIP_QUERY;
ihv3->code = 1;
ihv3->group = 0;
ihv3->qqic = amt->qi;
ihv3->nsrcs = 0;
ihv3->resv = 0;
ihv3->suppress = false;
ihv3->qrv = READ_ONCE(amt->net->ipv4.sysctl_igmp_qrv);
ihv3->csum = 0;
csum = &ihv3->csum;
csum_start = (void *)ihv3;
*csum = ip_compute_csum(csum_start, sizeof(*ihv3));
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
skb->ip_summed = CHECKSUM_NONE;
skb_push(skb, sizeof(*eth) + sizeof(*iph) + AMT_IPHDR_OPTS);
return skb;
}
static void amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
bool validate)
{
if (validate && amt->status >= status)
return;
netdev_dbg(amt->dev, "Update GW status %s -> %s",
status_str[amt->status], status_str[status]);
WRITE_ONCE(amt->status, status);
}
static void __amt_update_relay_status(struct amt_tunnel_list *tunnel,
enum amt_status status,
bool validate)
{
if (validate && tunnel->status >= status)
return;
netdev_dbg(tunnel->amt->dev,
"Update Tunnel(IP = %pI4, PORT = %u) status %s -> %s",
&tunnel->ip4, ntohs(tunnel->source_port),
status_str[tunnel->status], status_str[status]);
tunnel->status = status;
}
static void amt_update_relay_status(struct amt_tunnel_list *tunnel,
enum amt_status status, bool validate)
{
spin_lock_bh(&tunnel->lock);
__amt_update_relay_status(tunnel, status, validate);
spin_unlock_bh(&tunnel->lock);
}
static void amt_send_discovery(struct amt_dev *amt)
{
struct amt_header_discovery *amtd;
int hlen, tlen, offset;
struct socket *sock;
struct udphdr *udph;
struct sk_buff *skb;
struct iphdr *iph;
struct rtable *rt;
struct flowi4 fl4;
u32 len;
int err;
rcu_read_lock();
sock = rcu_dereference(amt->sock);
if (!sock)
goto out;
if (!netif_running(amt->stream_dev) || !netif_running(amt->dev))
goto out;
rt = ip_route_output_ports(amt->net, &fl4, sock->sk,
amt->discovery_ip, amt->local_ip,
amt->gw_port, amt->relay_port,
IPPROTO_UDP, 0,
amt->stream_dev->ifindex);
if (IS_ERR(rt)) {
amt->dev->stats.tx_errors++;
goto out;
}
hlen = LL_RESERVED_SPACE(amt->dev);
tlen = amt->dev->needed_tailroom;
len = hlen + tlen + sizeof(*iph) + sizeof(*udph) + sizeof(*amtd);
skb = netdev_alloc_skb_ip_align(amt->dev, len);
if (!skb) {
ip_rt_put(rt);
amt->dev->stats.tx_errors++;
goto out;
}
skb->priority = TC_PRIO_CONTROL;
skb_dst_set(skb, &rt->dst);
len = sizeof(*iph) + sizeof(*udph) + sizeof(*amtd);
skb_reset_network_header(skb);
skb_put(skb, len);
amtd = skb_pull(skb, sizeof(*iph) + sizeof(*udph));
amtd->version = 0;
amtd->type = AMT_MSG_DISCOVERY;
amtd->reserved = 0;
amtd->nonce = amt->nonce;
skb_push(skb, sizeof(*udph));
skb_reset_transport_header(skb);
udph = udp_hdr(skb);
udph->source = amt->gw_port;
udph->dest = amt->relay_port;
udph->len = htons(sizeof(*udph) + sizeof(*amtd));
udph->check = 0;
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
udph->check = csum_tcpudp_magic(amt->local_ip, amt->discovery_ip,
sizeof(*udph) + sizeof(*amtd),
IPPROTO_UDP, skb->csum);
skb_push(skb, sizeof(*iph));
iph = ip_hdr(skb);
iph->version = 4;
iph->ihl = (sizeof(struct iphdr)) >> 2;
iph->tos = AMT_TOS;
iph->frag_off = 0;
iph->ttl = ip4_dst_hoplimit(&rt->dst);
iph->daddr = amt->discovery_ip;
iph->saddr = amt->local_ip;
iph->protocol = IPPROTO_UDP;
iph->tot_len = htons(len);
skb->ip_summed = CHECKSUM_NONE;
ip_select_ident(amt->net, skb, NULL);
ip_send_check(iph);
err = ip_local_out(amt->net, sock->sk, skb);
if (unlikely(net_xmit_eval(err)))
amt->dev->stats.tx_errors++;
amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true);
out:
rcu_read_unlock();
}
static void amt_send_request(struct amt_dev *amt, bool v6)
{
struct amt_header_request *amtrh;
int hlen, tlen, offset;
struct socket *sock;
struct udphdr *udph;
struct sk_buff *skb;
struct iphdr *iph;
struct rtable *rt;
struct flowi4 fl4;
u32 len;
int err;
rcu_read_lock();
sock = rcu_dereference(amt->sock);
if (!sock)
goto out;
if (!netif_running(amt->stream_dev) || !netif_running(amt->dev))
goto out;
rt = ip_route_output_ports(amt->net, &fl4, sock->sk,
amt->remote_ip, amt->local_ip,
amt->gw_port, amt->relay_port,
IPPROTO_UDP, 0,
amt->stream_dev->ifindex);
if (IS_ERR(rt)) {
amt->dev->stats.tx_errors++;
goto out;
}
hlen = LL_RESERVED_SPACE(amt->dev);
tlen = amt->dev->needed_tailroom;
len = hlen + tlen + sizeof(*iph) + sizeof(*udph) + sizeof(*amtrh);
skb = netdev_alloc_skb_ip_align(amt->dev, len);
if (!skb) {
ip_rt_put(rt);
amt->dev->stats.tx_errors++;
goto out;
}
skb->priority = TC_PRIO_CONTROL;
skb_dst_set(skb, &rt->dst);
len = sizeof(*iph) + sizeof(*udph) + sizeof(*amtrh);
skb_reset_network_header(skb);
skb_put(skb, len);
amtrh = skb_pull(skb, sizeof(*iph) + sizeof(*udph));
amtrh->version = 0;
amtrh->type = AMT_MSG_REQUEST;
amtrh->reserved1 = 0;
amtrh->p = v6;
amtrh->reserved2 = 0;
amtrh->nonce = amt->nonce;
skb_push(skb, sizeof(*udph));
skb_reset_transport_header(skb);
udph = udp_hdr(skb);
udph->source = amt->gw_port;
udph->dest = amt->relay_port;
udph->len = htons(sizeof(*amtrh) + sizeof(*udph));
udph->check = 0;
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
udph->check = csum_tcpudp_magic(amt->local_ip, amt->remote_ip,
sizeof(*udph) + sizeof(*amtrh),
IPPROTO_UDP, skb->csum);
skb_push(skb, sizeof(*iph));
iph = ip_hdr(skb);
iph->version = 4;
iph->ihl = (sizeof(struct iphdr)) >> 2;
iph->tos = AMT_TOS;
iph->frag_off = 0;
iph->ttl = ip4_dst_hoplimit(&rt->dst);
iph->daddr = amt->remote_ip;
iph->saddr = amt->local_ip;
iph->protocol = IPPROTO_UDP;
iph->tot_len = htons(len);
skb->ip_summed = CHECKSUM_NONE;
ip_select_ident(amt->net, skb, NULL);
ip_send_check(iph);
err = ip_local_out(amt->net, sock->sk, skb);
if (unlikely(net_xmit_eval(err)))
amt->dev->stats.tx_errors++;
out:
rcu_read_unlock();
}
static void amt_send_igmp_gq(struct amt_dev *amt,
struct amt_tunnel_list *tunnel)
{
struct sk_buff *skb;
skb = amt_build_igmp_gq(amt);
if (!skb)
return;
amt_skb_cb(skb)->tunnel = tunnel;
dev_queue_xmit(skb);
}
#if IS_ENABLED(CONFIG_IPV6)
static struct sk_buff *amt_build_mld_gq(struct amt_dev *amt)
{
u8 ra[AMT_IP6HDR_OPTS] = { IPPROTO_ICMPV6, 0, IPV6_TLV_ROUTERALERT,
2, 0, 0, IPV6_TLV_PAD1, IPV6_TLV_PAD1 };
int hlen = LL_RESERVED_SPACE(amt->dev);
int tlen = amt->dev->needed_tailroom;
struct mld2_query *mld2q;
void *csum_start = NULL;
struct ipv6hdr *ip6h;
struct sk_buff *skb;
struct ethhdr *eth;
u32 len;
len = hlen + tlen + sizeof(*ip6h) + sizeof(ra) + sizeof(*mld2q);
skb = netdev_alloc_skb_ip_align(amt->dev, len);
if (!skb)
return NULL;
skb_reserve(skb, hlen);
skb_push(skb, sizeof(*eth));
skb_reset_mac_header(skb);
eth = eth_hdr(skb);
skb->priority = TC_PRIO_CONTROL;
skb->protocol = htons(ETH_P_IPV6);
skb_put_zero(skb, sizeof(*ip6h));
skb_put_data(skb, ra, sizeof(ra));
skb_put_zero(skb, sizeof(*mld2q));
skb_pull(skb, sizeof(*eth));
skb_reset_network_header(skb);
ip6h = ipv6_hdr(skb);
ip6h->payload_len = htons(sizeof(ra) + sizeof(*mld2q));
ip6h->nexthdr = NEXTHDR_HOP;
ip6h->hop_limit = 1;
ip6h->daddr = mld2_all_node;
ip6_flow_hdr(ip6h, 0, 0);
if (ipv6_dev_get_saddr(amt->net, amt->dev, &ip6h->daddr, 0,
&ip6h->saddr)) {
amt->dev->stats.tx_errors++;
kfree_skb(skb);
return NULL;
}
eth->h_proto = htons(ETH_P_IPV6);
ether_addr_copy(eth->h_source, amt->dev->dev_addr);
ipv6_eth_mc_map(&mld2_all_node, eth->h_dest);
skb_pull(skb, sizeof(*ip6h) + sizeof(ra));
skb_reset_transport_header(skb);
mld2q = (struct mld2_query *)icmp6_hdr(skb);
mld2q->mld2q_mrc = htons(1);
mld2q->mld2q_type = ICMPV6_MGM_QUERY;
mld2q->mld2q_code = 0;
mld2q->mld2q_cksum = 0;
mld2q->mld2q_resv1 = 0;
mld2q->mld2q_resv2 = 0;
mld2q->mld2q_suppress = 0;
mld2q->mld2q_qrv = amt->qrv;
mld2q->mld2q_nsrcs = 0;
mld2q->mld2q_qqic = amt->qi;
csum_start = (void *)mld2q;
mld2q->mld2q_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
sizeof(*mld2q),
IPPROTO_ICMPV6,
csum_partial(csum_start,
sizeof(*mld2q), 0));
skb->ip_summed = CHECKSUM_NONE;
skb_push(skb, sizeof(*eth) + sizeof(*ip6h) + sizeof(ra));
return skb;
}
static void amt_send_mld_gq(struct amt_dev *amt, struct amt_tunnel_list *tunnel)
{
struct sk_buff *skb;
skb = amt_build_mld_gq(amt);
if (!skb)
return;
amt_skb_cb(skb)->tunnel = tunnel;
dev_queue_xmit(skb);
}
#else
static void amt_send_mld_gq(struct amt_dev *amt, struct amt_tunnel_list *tunnel)
{
}
#endif
static bool amt_queue_event(struct amt_dev *amt, enum amt_event event,
struct sk_buff *skb)
{
int index;
spin_lock_bh(&amt->lock);
if (amt->nr_events >= AMT_MAX_EVENTS) {
spin_unlock_bh(&amt->lock);
return 1;
}
index = (amt->event_idx + amt->nr_events) % AMT_MAX_EVENTS;
amt->events[index].event = event;
amt->events[index].skb = skb;
amt->nr_events++;
amt->event_idx %= AMT_MAX_EVENTS;
queue_work(amt_wq, &amt->event_wq);
spin_unlock_bh(&amt->lock);
return 0;
}
static void amt_secret_work(struct work_struct *work)
{
struct amt_dev *amt = container_of(to_delayed_work(work),
struct amt_dev,
secret_wq);
spin_lock_bh(&amt->lock);
get_random_bytes(&amt->key, sizeof(siphash_key_t));
spin_unlock_bh(&amt->lock);
mod_delayed_work(amt_wq, &amt->secret_wq,
msecs_to_jiffies(AMT_SECRET_TIMEOUT));
}
static void amt_event_send_discovery(struct amt_dev *amt)
{
if (amt->status > AMT_STATUS_SENT_DISCOVERY)
goto out;
get_random_bytes(&amt->nonce, sizeof(__be32));
amt_send_discovery(amt);
out:
mod_delayed_work(amt_wq, &amt->discovery_wq,
msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT));
}
static void amt_discovery_work(struct work_struct *work)
{
struct amt_dev *amt = container_of(to_delayed_work(work),
struct amt_dev,
discovery_wq);
if (amt_queue_event(amt, AMT_EVENT_SEND_DISCOVERY, NULL))
mod_delayed_work(amt_wq, &amt->discovery_wq,
msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT));
}
static void amt_event_send_request(struct amt_dev *amt)
{
u32 exp;
if (amt->status < AMT_STATUS_RECEIVED_ADVERTISEMENT)
goto out;
if (amt->req_cnt > AMT_MAX_REQ_COUNT) {
netdev_dbg(amt->dev, "Gateway is not ready");
amt->qi = AMT_INIT_REQ_TIMEOUT;
WRITE_ONCE(amt->ready4, false);
WRITE_ONCE(amt->ready6, false);
amt->remote_ip = 0;
amt_update_gw_status(amt, AMT_STATUS_INIT, false);
amt->req_cnt = 0;
amt->nonce = 0;
goto out;
}
if (!amt->req_cnt) {
WRITE_ONCE(amt->ready4, false);
WRITE_ONCE(amt->ready6, false);
get_random_bytes(&amt->nonce, sizeof(__be32));
}
amt_send_request(amt, false);
amt_send_request(amt, true);
amt_update_gw_status(amt, AMT_STATUS_SENT_REQUEST, true);
amt->req_cnt++;
out:
exp = min_t(u32, (1 * (1 << amt->req_cnt)), AMT_MAX_REQ_TIMEOUT);
mod_delayed_work(amt_wq, &amt->req_wq, msecs_to_jiffies(exp * 1000));
}
static void amt_req_work(struct work_struct *work)
{
struct amt_dev *amt = container_of(to_delayed_work(work),
struct amt_dev,
req_wq);
if (amt_queue_event(amt, AMT_EVENT_SEND_REQUEST, NULL))
mod_delayed_work(amt_wq, &amt->req_wq,
msecs_to_jiffies(100));
}
static bool amt_send_membership_update(struct amt_dev *amt,
struct sk_buff *skb,
bool v6)
{
struct amt_header_membership_update *amtmu;
struct socket *sock;
struct iphdr *iph;
struct flowi4 fl4;
struct rtable *rt;
int err;
sock = rcu_dereference_bh(amt->sock);
if (!sock)
return true;
err = skb_cow_head(skb, LL_RESERVED_SPACE(amt->dev) + sizeof(*amtmu) +
sizeof(*iph) + sizeof(struct udphdr));
if (err)
return true;
skb_reset_inner_headers(skb);
memset(&fl4, 0, sizeof(struct flowi4));
fl4.flowi4_oif = amt->stream_dev->ifindex;
fl4.daddr = amt->remote_ip;
fl4.saddr = amt->local_ip;
fl4.flowi4_tos = AMT_TOS;
fl4.flowi4_proto = IPPROTO_UDP;
rt = ip_route_output_key(amt->net, &fl4);
if (IS_ERR(rt)) {
netdev_dbg(amt->dev, "no route to %pI4\n", &amt->remote_ip);
return true;
}
amtmu = skb_push(skb, sizeof(*amtmu));
amtmu->version = 0;
amtmu->type = AMT_MSG_MEMBERSHIP_UPDATE;
amtmu->reserved = 0;
amtmu->nonce = amt->nonce;
amtmu->response_mac = amt->mac;
if (!v6)
skb_set_inner_protocol(skb, htons(ETH_P_IP));
else
skb_set_inner_protocol(skb, htons(ETH_P_IPV6));
udp_tunnel_xmit_skb(rt, sock->sk, skb,
fl4.saddr,
fl4.daddr,
AMT_TOS,
ip4_dst_hoplimit(&rt->dst),
0,
amt->gw_port,
amt->relay_port,
false,
false);
amt_update_gw_status(amt, AMT_STATUS_SENT_UPDATE, true);
return false;
}
static void amt_send_multicast_data(struct amt_dev *amt,
const struct sk_buff *oskb,
struct amt_tunnel_list *tunnel,
bool v6)
{
struct amt_header_mcast_data *amtmd;
struct socket *sock;
struct sk_buff *skb;
struct iphdr *iph;
struct flowi4 fl4;
struct rtable *rt;
sock = rcu_dereference_bh(amt->sock);
if (!sock)
return;
skb = skb_copy_expand(oskb, sizeof(*amtmd) + sizeof(*iph) +
sizeof(struct udphdr), 0, GFP_ATOMIC);
if (!skb)
return;
skb_reset_inner_headers(skb);
memset(&fl4, 0, sizeof(struct flowi4));
fl4.flowi4_oif = amt->stream_dev->ifindex;
fl4.daddr = tunnel->ip4;
fl4.saddr = amt->local_ip;
fl4.flowi4_proto = IPPROTO_UDP;
rt = ip_route_output_key(amt->net, &fl4);
if (IS_ERR(rt)) {
netdev_dbg(amt->dev, "no route to %pI4\n", &tunnel->ip4);
kfree_skb(skb);
return;
}
amtmd = skb_push(skb, sizeof(*amtmd));
amtmd->version = 0;
amtmd->reserved = 0;
amtmd->type = AMT_MSG_MULTICAST_DATA;
if (!v6)
skb_set_inner_protocol(skb, htons(ETH_P_IP));
else
skb_set_inner_protocol(skb, htons(ETH_P_IPV6));
udp_tunnel_xmit_skb(rt, sock->sk, skb,
fl4.saddr,
fl4.daddr,
AMT_TOS,
ip4_dst_hoplimit(&rt->dst),
0,
amt->relay_port,
tunnel->source_port,
false,
false);
}
static bool amt_send_membership_query(struct amt_dev *amt,
struct sk_buff *skb,
struct amt_tunnel_list *tunnel,
bool v6)
{
struct amt_header_membership_query *amtmq;
struct socket *sock;
struct rtable *rt;
struct flowi4 fl4;
int err;
sock = rcu_dereference_bh(amt->sock);
if (!sock)
return true;
err = skb_cow_head(skb, LL_RESERVED_SPACE(amt->dev) + sizeof(*amtmq) +
sizeof(struct iphdr) + sizeof(struct udphdr));
if (err)
return true;
skb_reset_inner_headers(skb);
memset(&fl4, 0, sizeof(struct flowi4));
fl4.flowi4_oif = amt->stream_dev->ifindex;
fl4.daddr = tunnel->ip4;
fl4.saddr = amt->local_ip;
fl4.flowi4_tos = AMT_TOS;
fl4.flowi4_proto = IPPROTO_UDP;
rt = ip_route_output_key(amt->net, &fl4);
if (IS_ERR(rt)) {
netdev_dbg(amt->dev, "no route to %pI4\n", &tunnel->ip4);
return true;
}
amtmq = skb_push(skb, sizeof(*amtmq));
amtmq->version = 0;
amtmq->type = AMT_MSG_MEMBERSHIP_QUERY;
amtmq->reserved = 0;
amtmq->l = 0;
amtmq->g = 0;
amtmq->nonce = tunnel->nonce;
amtmq->response_mac = tunnel->mac;
if (!v6)
skb_set_inner_protocol(skb, htons(ETH_P_IP));
else
skb_set_inner_protocol(skb, htons(ETH_P_IPV6));
udp_tunnel_xmit_skb(rt, sock->sk, skb,
fl4.saddr,
fl4.daddr,
AMT_TOS,
ip4_dst_hoplimit(&rt->dst),
0,
amt->relay_port,
tunnel->source_port,
false,
false);
amt_update_relay_status(tunnel, AMT_STATUS_SENT_QUERY, true);
return false;
}
static netdev_tx_t amt_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct amt_dev *amt = netdev_priv(dev);
struct amt_tunnel_list *tunnel;
struct amt_group_node *gnode;
union amt_addr group = {0,};
#if IS_ENABLED(CONFIG_IPV6)
struct ipv6hdr *ip6h;
struct mld_msg *mld;
#endif
bool report = false;
struct igmphdr *ih;
bool query = false;
struct iphdr *iph;
bool data = false;
bool v6 = false;
u32 hash;
iph = ip_hdr(skb);
if (iph->version == 4) {
if (!ipv4_is_multicast(iph->daddr))
goto free;
if (!ip_mc_check_igmp(skb)) {
ih = igmp_hdr(skb);
switch (ih->type) {
case IGMPV3_HOST_MEMBERSHIP_REPORT:
case IGMP_HOST_MEMBERSHIP_REPORT:
report = true;
break;
case IGMP_HOST_MEMBERSHIP_QUERY:
query = true;
break;
default:
goto free;
}
} else {
data = true;
}
v6 = false;
group.ip4 = iph->daddr;
#if IS_ENABLED(CONFIG_IPV6)
} else if (iph->version == 6) {
ip6h = ipv6_hdr(skb);
if (!ipv6_addr_is_multicast(&ip6h->daddr))
goto free;
if (!ipv6_mc_check_mld(skb)) {
mld = (struct mld_msg *)skb_transport_header(skb);
switch (mld->mld_type) {
case ICMPV6_MGM_REPORT:
case ICMPV6_MLD2_REPORT:
report = true;
break;
case ICMPV6_MGM_QUERY:
query = true;
break;
default:
goto free;
}
} else {
data = true;
}
v6 = true;
group.ip6 = ip6h->daddr;
#endif
} else {
dev->stats.tx_errors++;
goto free;
}
if (!pskb_may_pull(skb, sizeof(struct ethhdr)))
goto free;
skb_pull(skb, sizeof(struct ethhdr));
if (amt->mode == AMT_MODE_GATEWAY) {
/* Gateway only passes IGMP/MLD packets */
if (!report)
goto free;
if ((!v6 && !READ_ONCE(amt->ready4)) ||
(v6 && !READ_ONCE(amt->ready6)))
goto free;
if (amt_send_membership_update(amt, skb, v6))
goto free;
goto unlock;
} else if (amt->mode == AMT_MODE_RELAY) {
if (query) {
tunnel = amt_skb_cb(skb)->tunnel;
if (!tunnel) {
WARN_ON(1);
goto free;
}
/* Do not forward unexpected query */
if (amt_send_membership_query(amt, skb, tunnel, v6))
goto free;
goto unlock;
}
if (!data)
goto free;
list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list) {
hash = amt_group_hash(tunnel, &group);
hlist_for_each_entry_rcu(gnode, &tunnel->groups[hash],
node) {
if (!v6) {
if (gnode->group_addr.ip4 == iph->daddr)
goto found;
#if IS_ENABLED(CONFIG_IPV6)
} else {
if (ipv6_addr_equal(&gnode->group_addr.ip6,
&ip6h->daddr))
goto found;
#endif
}
}
continue;
found:
amt_send_multicast_data(amt, skb, tunnel, v6);
}
}
dev_kfree_skb(skb);
return NETDEV_TX_OK;
free:
dev_kfree_skb(skb);
unlock:
dev->stats.tx_dropped++;
return NETDEV_TX_OK;
}
static int amt_parse_type(struct sk_buff *skb)
{
struct amt_header *amth;
if (!pskb_may_pull(skb, sizeof(struct udphdr) +
sizeof(struct amt_header)))
return -1;
amth = (struct amt_header *)(udp_hdr(skb) + 1);
if (amth->version != 0)
return -1;
if (amth->type >= __AMT_MSG_MAX || !amth->type)
return -1;
return amth->type;
}
static void amt_clear_groups(struct amt_tunnel_list *tunnel)
{
struct amt_dev *amt = tunnel->amt;
struct amt_group_node *gnode;
struct hlist_node *t;
int i;
spin_lock_bh(&tunnel->lock);
rcu_read_lock();
for (i = 0; i < amt->hash_buckets; i++)
hlist_for_each_entry_safe(gnode, t, &tunnel->groups[i], node)
amt_del_group(amt, gnode);
rcu_read_unlock();
spin_unlock_bh(&tunnel->lock);
}
static void amt_tunnel_expire(struct work_struct *work)
{
struct amt_tunnel_list *tunnel = container_of(to_delayed_work(work),
struct amt_tunnel_list,
gc_wq);
struct amt_dev *amt = tunnel->amt;
spin_lock_bh(&amt->lock);
rcu_read_lock();
list_del_rcu(&tunnel->list);
amt->nr_tunnels--;
amt_clear_groups(tunnel);
rcu_read_unlock();
spin_unlock_bh(&amt->lock);
kfree_rcu(tunnel, rcu);
}
static void amt_cleanup_srcs(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode)
{
struct amt_source_node *snode;
struct hlist_node *t;
int i;
/* Delete old sources */
for (i = 0; i < amt->hash_buckets; i++) {
hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node) {
if (snode->flags == AMT_SOURCE_OLD)
amt_destroy_source(snode);
}
}
/* switch from new to old */
for (i = 0; i < amt->hash_buckets; i++) {
hlist_for_each_entry_rcu(snode, &gnode->sources[i], node) {
snode->flags = AMT_SOURCE_OLD;
if (!gnode->v6)
netdev_dbg(snode->gnode->amt->dev,
"Add source as OLD %pI4 from %pI4\n",
&snode->source_addr.ip4,
&gnode->group_addr.ip4);
#if IS_ENABLED(CONFIG_IPV6)
else
netdev_dbg(snode->gnode->amt->dev,
"Add source as OLD %pI6 from %pI6\n",
&snode->source_addr.ip6,
&gnode->group_addr.ip6);
#endif
}
}
}
static void amt_add_srcs(struct amt_dev *amt, struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode, void *grec,
bool v6)
{
struct igmpv3_grec *igmp_grec;
struct amt_source_node *snode;
#if IS_ENABLED(CONFIG_IPV6)
struct mld2_grec *mld_grec;
#endif
union amt_addr src = {0,};
u16 nsrcs;
u32 hash;
int i;
if (!v6) {
igmp_grec = grec;
nsrcs = ntohs(igmp_grec->grec_nsrcs);
} else {
#if IS_ENABLED(CONFIG_IPV6)
mld_grec = grec;
nsrcs = ntohs(mld_grec->grec_nsrcs);
#else
return;
#endif
}
for (i = 0; i < nsrcs; i++) {
if (tunnel->nr_sources >= amt->max_sources)
return;
if (!v6)
src.ip4 = igmp_grec->grec_src[i];
#if IS_ENABLED(CONFIG_IPV6)
else
memcpy(&src.ip6, &mld_grec->grec_src[i],
sizeof(struct in6_addr));
#endif
if (amt_lookup_src(tunnel, gnode, AMT_FILTER_ALL, &src))
continue;
snode = amt_alloc_snode(gnode, &src);
if (snode) {
hash = amt_source_hash(tunnel, &snode->source_addr);
hlist_add_head_rcu(&snode->node, &gnode->sources[hash]);
tunnel->nr_sources++;
gnode->nr_sources++;
if (!gnode->v6)
netdev_dbg(snode->gnode->amt->dev,
"Add source as NEW %pI4 from %pI4\n",
&snode->source_addr.ip4,
&gnode->group_addr.ip4);
#if IS_ENABLED(CONFIG_IPV6)
else
netdev_dbg(snode->gnode->amt->dev,
"Add source as NEW %pI6 from %pI6\n",
&snode->source_addr.ip6,
&gnode->group_addr.ip6);
#endif
}
}
}
/* Router State Report Rec'd New Router State
* ------------ ------------ ----------------
* EXCLUDE (X,Y) IS_IN (A) EXCLUDE (X+A,Y-A)
*
* -----------+-----------+-----------+
* | OLD | NEW |
* -----------+-----------+-----------+
* FWD | X | X+A |
* -----------+-----------+-----------+
* D_FWD | Y | Y-A |
* -----------+-----------+-----------+
* NONE | | A |
* -----------+-----------+-----------+
*
* a) Received sources are NONE/NEW
* b) All NONE will be deleted by amt_cleanup_srcs().
* c) All OLD will be deleted by amt_cleanup_srcs().
* d) After delete, NEW source will be switched to OLD.
*/
static void amt_lookup_act_srcs(struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec,
enum amt_ops ops,
enum amt_filter filter,
enum amt_act act,
bool v6)
{
struct amt_dev *amt = tunnel->amt;
struct amt_source_node *snode;
struct igmpv3_grec *igmp_grec;
#if IS_ENABLED(CONFIG_IPV6)
struct mld2_grec *mld_grec;
#endif
union amt_addr src = {0,};
struct hlist_node *t;
u16 nsrcs;
int i, j;
if (!v6) {
igmp_grec = grec;
nsrcs = ntohs(igmp_grec->grec_nsrcs);
} else {
#if IS_ENABLED(CONFIG_IPV6)
mld_grec = grec;
nsrcs = ntohs(mld_grec->grec_nsrcs);
#else
return;
#endif
}
memset(&src, 0, sizeof(union amt_addr));
switch (ops) {
case AMT_OPS_INT:
/* A*B */
for (i = 0; i < nsrcs; i++) {
if (!v6)
src.ip4 = igmp_grec->grec_src[i];
#if IS_ENABLED(CONFIG_IPV6)
else
memcpy(&src.ip6, &mld_grec->grec_src[i],
sizeof(struct in6_addr));
#endif
snode = amt_lookup_src(tunnel, gnode, filter, &src);
if (!snode)
continue;
amt_act_src(tunnel, gnode, snode, act);
}
break;
case AMT_OPS_UNI:
/* A+B */
for (i = 0; i < amt->hash_buckets; i++) {
hlist_for_each_entry_safe(snode, t, &gnode->sources[i],
node) {
if (amt_status_filter(snode, filter))
amt_act_src(tunnel, gnode, snode, act);
}
}
for (i = 0; i < nsrcs; i++) {
if (!v6)
src.ip4 = igmp_grec->grec_src[i];
#if IS_ENABLED(CONFIG_IPV6)
else
memcpy(&src.ip6, &mld_grec->grec_src[i],
sizeof(struct in6_addr));
#endif
snode = amt_lookup_src(tunnel, gnode, filter, &src);
if (!snode)
continue;
amt_act_src(tunnel, gnode, snode, act);
}
break;
case AMT_OPS_SUB:
/* A-B */
for (i = 0; i < amt->hash_buckets; i++) {
hlist_for_each_entry_safe(snode, t, &gnode->sources[i],
node) {
if (!amt_status_filter(snode, filter))
continue;
for (j = 0; j < nsrcs; j++) {
if (!v6)
src.ip4 = igmp_grec->grec_src[j];
#if IS_ENABLED(CONFIG_IPV6)
else
memcpy(&src.ip6,
&mld_grec->grec_src[j],
sizeof(struct in6_addr));
#endif
if (amt_addr_equal(&snode->source_addr,
&src))
goto out_sub;
}
amt_act_src(tunnel, gnode, snode, act);
continue;
out_sub:;
}
}
break;
case AMT_OPS_SUB_REV:
/* B-A */
for (i = 0; i < nsrcs; i++) {
if (!v6)
src.ip4 = igmp_grec->grec_src[i];
#if IS_ENABLED(CONFIG_IPV6)
else
memcpy(&src.ip6, &mld_grec->grec_src[i],
sizeof(struct in6_addr));
#endif
snode = amt_lookup_src(tunnel, gnode, AMT_FILTER_ALL,
&src);
if (!snode) {
snode = amt_lookup_src(tunnel, gnode,
filter, &src);
if (snode)
amt_act_src(tunnel, gnode, snode, act);
}
}
break;
default:
netdev_dbg(amt->dev, "Invalid type\n");
return;
}
}
static void amt_mcast_is_in_handler(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec, void *zero_grec, bool v6)
{
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* INCLUDE (A) IS_IN (B) INCLUDE (A+B) (B)=GMI
*/
/* Update IS_IN (B) as FWD/NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_NONE_NEW,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* Update INCLUDE (A) as NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* (B)=GMI */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD_NEW,
AMT_ACT_GMI,
v6);
} else {
/* State Actions
* ------------ ------------ ---------------- -------
* EXCLUDE (X,Y) IS_IN (A) EXCLUDE (X+A,Y-A) (A)=GMI
*/
/* Update (A) in (X, Y) as NONE/NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_BOTH,
AMT_ACT_STATUS_NONE_NEW,
v6);
/* Update FWD/OLD as FWD/NEW */
amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* Update IS_IN (A) as FWD/NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_NONE_NEW,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* Update EXCLUDE (, Y-A) as D_FWD_NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
}
}
static void amt_mcast_is_ex_handler(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec, void *zero_grec, bool v6)
{
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* INCLUDE (A) IS_EX (B) EXCLUDE (A*B,B-A) (B-A)=0
* Delete (A-B)
* Group Timer=GMI
*/
/* EXCLUDE(A*B, ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE(, B-A) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
/* (B-A)=0 */
amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI,
AMT_FILTER_D_FWD_NEW,
AMT_ACT_GMI_ZERO,
v6);
/* Group Timer=GMI */
if (!mod_delayed_work(amt_wq, &gnode->group_timer,
msecs_to_jiffies(amt_gmi(amt))))
dev_hold(amt->dev);
gnode->filter_mode = MCAST_EXCLUDE;
/* Delete (A-B) will be worked by amt_cleanup_srcs(). */
} else {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* EXCLUDE (X,Y) IS_EX (A) EXCLUDE (A-Y,Y*A) (A-X-Y)=GMI
* Delete (X-A)
* Delete (Y-A)
* Group Timer=GMI
*/
/* EXCLUDE (A-Y, ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (, Y*A ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
/* (A-X-Y)=GMI */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_BOTH_NEW,
AMT_ACT_GMI,
v6);
/* Group Timer=GMI */
if (!mod_delayed_work(amt_wq, &gnode->group_timer,
msecs_to_jiffies(amt_gmi(amt))))
dev_hold(amt->dev);
/* Delete (X-A), (Y-A) will be worked by amt_cleanup_srcs(). */
}
}
static void amt_mcast_to_in_handler(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec, void *zero_grec, bool v6)
{
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* INCLUDE (A) TO_IN (B) INCLUDE (A+B) (B)=GMI
* Send Q(G,A-B)
*/
/* Update TO_IN (B) sources as FWD/NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_NONE_NEW,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* Update INCLUDE (A) sources as NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* (B)=GMI */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD_NEW,
AMT_ACT_GMI,
v6);
} else {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* EXCLUDE (X,Y) TO_IN (A) EXCLUDE (X+A,Y-A) (A)=GMI
* Send Q(G,X-A)
* Send Q(G)
*/
/* Update TO_IN (A) sources as FWD/NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_NONE_NEW,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* Update EXCLUDE(X,) sources as FWD/NEW */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (, Y-A)
* (A) are already switched to FWD_NEW.
* So, D_FWD/OLD -> D_FWD/NEW is okay.
*/
amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
/* (A)=GMI
* Only FWD_NEW will have (A) sources.
*/
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD_NEW,
AMT_ACT_GMI,
v6);
}
}
static void amt_mcast_to_ex_handler(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec, void *zero_grec, bool v6)
{
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* INCLUDE (A) TO_EX (B) EXCLUDE (A*B,B-A) (B-A)=0
* Delete (A-B)
* Send Q(G,A*B)
* Group Timer=GMI
*/
/* EXCLUDE (A*B, ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (, B-A) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
/* (B-A)=0 */
amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI,
AMT_FILTER_D_FWD_NEW,
AMT_ACT_GMI_ZERO,
v6);
/* Group Timer=GMI */
if (!mod_delayed_work(amt_wq, &gnode->group_timer,
msecs_to_jiffies(amt_gmi(amt))))
dev_hold(amt->dev);
gnode->filter_mode = MCAST_EXCLUDE;
/* Delete (A-B) will be worked by amt_cleanup_srcs(). */
} else {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* EXCLUDE (X,Y) TO_EX (A) EXCLUDE (A-Y,Y*A) (A-X-Y)=Group Timer
* Delete (X-A)
* Delete (Y-A)
* Send Q(G,A-Y)
* Group Timer=GMI
*/
/* Update (A-X-Y) as NONE/OLD */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_BOTH,
AMT_ACT_GT,
v6);
/* EXCLUDE (A-Y, ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (, Y*A) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
/* Group Timer=GMI */
if (!mod_delayed_work(amt_wq, &gnode->group_timer,
msecs_to_jiffies(amt_gmi(amt))))
dev_hold(amt->dev);
/* Delete (X-A), (Y-A) will be worked by amt_cleanup_srcs(). */
}
}
static void amt_mcast_allow_handler(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec, void *zero_grec, bool v6)
{
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* INCLUDE (A) ALLOW (B) INCLUDE (A+B) (B)=GMI
*/
/* INCLUDE (A+B) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* (B)=GMI */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD_NEW,
AMT_ACT_GMI,
v6);
} else {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* EXCLUDE (X,Y) ALLOW (A) EXCLUDE (X+A,Y-A) (A)=GMI
*/
/* EXCLUDE (X+A, ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (, Y-A) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
/* (A)=GMI
* All (A) source are now FWD/NEW status.
*/
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT,
AMT_FILTER_FWD_NEW,
AMT_ACT_GMI,
v6);
}
}
static void amt_mcast_block_handler(struct amt_dev *amt,
struct amt_tunnel_list *tunnel,
struct amt_group_node *gnode,
void *grec, void *zero_grec, bool v6)
{
if (gnode->filter_mode == MCAST_INCLUDE) {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* INCLUDE (A) BLOCK (B) INCLUDE (A) Send Q(G,A*B)
*/
/* INCLUDE (A) */
amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
} else {
/* Router State Report Rec'd New Router State Actions
* ------------ ------------ ---------------- -------
* EXCLUDE (X,Y) BLOCK (A) EXCLUDE (X+(A-Y),Y) (A-X-Y)=Group Timer
* Send Q(G,A-Y)
*/
/* (A-X-Y)=Group Timer */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_BOTH,
AMT_ACT_GT,
v6);
/* EXCLUDE (X, ) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (X+(A-Y) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_FWD_NEW,
v6);
/* EXCLUDE (, Y) */
amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI,
AMT_FILTER_D_FWD,
AMT_ACT_STATUS_D_FWD_NEW,
v6);
}
}
/* RFC 3376
* 7.3.2. In the Presence of Older Version Group Members
*
* When Group Compatibility Mode is IGMPv2, a router internally
* translates the following IGMPv2 messages for that group to their
* IGMPv3 equivalents:
*
* IGMPv2 Message IGMPv3 Equivalent
* -------------- -----------------
* Report IS_EX( {} )
* Leave TO_IN( {} )
*/
static void amt_igmpv2_report_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct igmphdr *ih = igmp_hdr(skb);
struct iphdr *iph = ip_hdr(skb);
struct amt_group_node *gnode;
union amt_addr group, host;
memset(&group, 0, sizeof(union amt_addr));
group.ip4 = ih->group;
memset(&host, 0, sizeof(union amt_addr));
host.ip4 = iph->saddr;
gnode = amt_lookup_group(tunnel, &group, &host, false);
if (!gnode) {
gnode = amt_add_group(amt, tunnel, &group, &host, false);
if (!IS_ERR(gnode)) {
gnode->filter_mode = MCAST_EXCLUDE;
if (!mod_delayed_work(amt_wq, &gnode->group_timer,
msecs_to_jiffies(amt_gmi(amt))))
dev_hold(amt->dev);
}
}
}
/* RFC 3376
* 7.3.2. In the Presence of Older Version Group Members
*
* When Group Compatibility Mode is IGMPv2, a router internally
* translates the following IGMPv2 messages for that group to their
* IGMPv3 equivalents:
*
* IGMPv2 Message IGMPv3 Equivalent
* -------------- -----------------
* Report IS_EX( {} )
* Leave TO_IN( {} )
*/
static void amt_igmpv2_leave_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct igmphdr *ih = igmp_hdr(skb);
struct iphdr *iph = ip_hdr(skb);
struct amt_group_node *gnode;
union amt_addr group, host;
memset(&group, 0, sizeof(union amt_addr));
group.ip4 = ih->group;
memset(&host, 0, sizeof(union amt_addr));
host.ip4 = iph->saddr;
gnode = amt_lookup_group(tunnel, &group, &host, false);
if (gnode)
amt_del_group(amt, gnode);
}
static void amt_igmpv3_report_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct igmpv3_report *ihrv3 = igmpv3_report_hdr(skb);
int len = skb_transport_offset(skb) + sizeof(*ihrv3);
void *zero_grec = (void *)&igmpv3_zero_grec;
struct iphdr *iph = ip_hdr(skb);
struct amt_group_node *gnode;
union amt_addr group, host;
struct igmpv3_grec *grec;
u16 nsrcs;
int i;
for (i = 0; i < ntohs(ihrv3->ngrec); i++) {
len += sizeof(*grec);
if (!ip_mc_may_pull(skb, len))
break;
grec = (void *)(skb->data + len - sizeof(*grec));
nsrcs = ntohs(grec->grec_nsrcs);
len += nsrcs * sizeof(__be32);
if (!ip_mc_may_pull(skb, len))
break;
memset(&group, 0, sizeof(union amt_addr));
group.ip4 = grec->grec_mca;
memset(&host, 0, sizeof(union amt_addr));
host.ip4 = iph->saddr;
gnode = amt_lookup_group(tunnel, &group, &host, false);
if (!gnode) {
gnode = amt_add_group(amt, tunnel, &group, &host,
false);
if (IS_ERR(gnode))
continue;
}
amt_add_srcs(amt, tunnel, gnode, grec, false);
switch (grec->grec_type) {
case IGMPV3_MODE_IS_INCLUDE:
amt_mcast_is_in_handler(amt, tunnel, gnode, grec,
zero_grec, false);
break;
case IGMPV3_MODE_IS_EXCLUDE:
amt_mcast_is_ex_handler(amt, tunnel, gnode, grec,
zero_grec, false);
break;
case IGMPV3_CHANGE_TO_INCLUDE:
amt_mcast_to_in_handler(amt, tunnel, gnode, grec,
zero_grec, false);
break;
case IGMPV3_CHANGE_TO_EXCLUDE:
amt_mcast_to_ex_handler(amt, tunnel, gnode, grec,
zero_grec, false);
break;
case IGMPV3_ALLOW_NEW_SOURCES:
amt_mcast_allow_handler(amt, tunnel, gnode, grec,
zero_grec, false);
break;
case IGMPV3_BLOCK_OLD_SOURCES:
amt_mcast_block_handler(amt, tunnel, gnode, grec,
zero_grec, false);
break;
default:
break;
}
amt_cleanup_srcs(amt, tunnel, gnode);
}
}
/* caller held tunnel->lock */
static void amt_igmp_report_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct igmphdr *ih = igmp_hdr(skb);
switch (ih->type) {
case IGMPV3_HOST_MEMBERSHIP_REPORT:
amt_igmpv3_report_handler(amt, skb, tunnel);
break;
case IGMPV2_HOST_MEMBERSHIP_REPORT:
amt_igmpv2_report_handler(amt, skb, tunnel);
break;
case IGMP_HOST_LEAVE_MESSAGE:
amt_igmpv2_leave_handler(amt, skb, tunnel);
break;
default:
break;
}
}
#if IS_ENABLED(CONFIG_IPV6)
/* RFC 3810
* 8.3.2. In the Presence of MLDv1 Multicast Address Listeners
*
* When Multicast Address Compatibility Mode is MLDv2, a router acts
* using the MLDv2 protocol for that multicast address. When Multicast
* Address Compatibility Mode is MLDv1, a router internally translates
* the following MLDv1 messages for that multicast address to their
* MLDv2 equivalents:
*
* MLDv1 Message MLDv2 Equivalent
* -------------- -----------------
* Report IS_EX( {} )
* Done TO_IN( {} )
*/
static void amt_mldv1_report_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct mld_msg *mld = (struct mld_msg *)icmp6_hdr(skb);
struct ipv6hdr *ip6h = ipv6_hdr(skb);
struct amt_group_node *gnode;
union amt_addr group, host;
memcpy(&group.ip6, &mld->mld_mca, sizeof(struct in6_addr));
memcpy(&host.ip6, &ip6h->saddr, sizeof(struct in6_addr));
gnode = amt_lookup_group(tunnel, &group, &host, true);
if (!gnode) {
gnode = amt_add_group(amt, tunnel, &group, &host, true);
if (!IS_ERR(gnode)) {
gnode->filter_mode = MCAST_EXCLUDE;
if (!mod_delayed_work(amt_wq, &gnode->group_timer,
msecs_to_jiffies(amt_gmi(amt))))
dev_hold(amt->dev);
}
}
}
/* RFC 3810
* 8.3.2. In the Presence of MLDv1 Multicast Address Listeners
*
* When Multicast Address Compatibility Mode is MLDv2, a router acts
* using the MLDv2 protocol for that multicast address. When Multicast
* Address Compatibility Mode is MLDv1, a router internally translates
* the following MLDv1 messages for that multicast address to their
* MLDv2 equivalents:
*
* MLDv1 Message MLDv2 Equivalent
* -------------- -----------------
* Report IS_EX( {} )
* Done TO_IN( {} )
*/
static void amt_mldv1_leave_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct mld_msg *mld = (struct mld_msg *)icmp6_hdr(skb);
struct iphdr *iph = ip_hdr(skb);
struct amt_group_node *gnode;
union amt_addr group, host;
memcpy(&group.ip6, &mld->mld_mca, sizeof(struct in6_addr));
memset(&host, 0, sizeof(union amt_addr));
host.ip4 = iph->saddr;
gnode = amt_lookup_group(tunnel, &group, &host, true);
if (gnode) {
amt_del_group(amt, gnode);
return;
}
}
static void amt_mldv2_report_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct mld2_report *mld2r = (struct mld2_report *)icmp6_hdr(skb);
int len = skb_transport_offset(skb) + sizeof(*mld2r);
void *zero_grec = (void *)&mldv2_zero_grec;
struct ipv6hdr *ip6h = ipv6_hdr(skb);
struct amt_group_node *gnode;
union amt_addr group, host;
struct mld2_grec *grec;
u16 nsrcs;
int i;
for (i = 0; i < ntohs(mld2r->mld2r_ngrec); i++) {
len += sizeof(*grec);
if (!ipv6_mc_may_pull(skb, len))
break;
grec = (void *)(skb->data + len - sizeof(*grec));
nsrcs = ntohs(grec->grec_nsrcs);
len += nsrcs * sizeof(struct in6_addr);
if (!ipv6_mc_may_pull(skb, len))
break;
memset(&group, 0, sizeof(union amt_addr));
group.ip6 = grec->grec_mca;
memset(&host, 0, sizeof(union amt_addr));
host.ip6 = ip6h->saddr;
gnode = amt_lookup_group(tunnel, &group, &host, true);
if (!gnode) {
gnode = amt_add_group(amt, tunnel, &group, &host,
ETH_P_IPV6);
if (IS_ERR(gnode))
continue;
}
amt_add_srcs(amt, tunnel, gnode, grec, true);
switch (grec->grec_type) {
case MLD2_MODE_IS_INCLUDE:
amt_mcast_is_in_handler(amt, tunnel, gnode, grec,
zero_grec, true);
break;
case MLD2_MODE_IS_EXCLUDE:
amt_mcast_is_ex_handler(amt, tunnel, gnode, grec,
zero_grec, true);
break;
case MLD2_CHANGE_TO_INCLUDE:
amt_mcast_to_in_handler(amt, tunnel, gnode, grec,
zero_grec, true);
break;
case MLD2_CHANGE_TO_EXCLUDE:
amt_mcast_to_ex_handler(amt, tunnel, gnode, grec,
zero_grec, true);
break;
case MLD2_ALLOW_NEW_SOURCES:
amt_mcast_allow_handler(amt, tunnel, gnode, grec,
zero_grec, true);
break;
case MLD2_BLOCK_OLD_SOURCES:
amt_mcast_block_handler(amt, tunnel, gnode, grec,
zero_grec, true);
break;
default:
break;
}
amt_cleanup_srcs(amt, tunnel, gnode);
}
}
/* caller held tunnel->lock */
static void amt_mld_report_handler(struct amt_dev *amt, struct sk_buff *skb,
struct amt_tunnel_list *tunnel)
{
struct mld_msg *mld = (struct mld_msg *)icmp6_hdr(skb);
switch (mld->mld_type) {
case ICMPV6_MGM_REPORT:
amt_mldv1_report_handler(amt, skb, tunnel);
break;
case ICMPV6_MLD2_REPORT:
amt_mldv2_report_handler(amt, skb, tunnel);
break;
case ICMPV6_MGM_REDUCTION:
amt_mldv1_leave_handler(amt, skb, tunnel);
break;
default:
break;
}
}
#endif
static bool amt_advertisement_handler(struct amt_dev *amt, struct sk_buff *skb)
{
struct amt_header_advertisement *amta;
int hdr_size;
hdr_size = sizeof(*amta) + sizeof(struct udphdr);
if (!pskb_may_pull(skb, hdr_size))
return true;
amta = (struct amt_header_advertisement *)(udp_hdr(skb) + 1);
if (!amta->ip4)
return true;
if (amta->reserved || amta->version)
return true;
if (ipv4_is_loopback(amta->ip4) || ipv4_is_multicast(amta->ip4) ||
ipv4_is_zeronet(amta->ip4))
return true;
if (amt->status != AMT_STATUS_SENT_DISCOVERY ||
amt->nonce != amta->nonce)
return true;
amt->remote_ip = amta->ip4;
netdev_dbg(amt->dev, "advertised remote ip = %pI4\n", &amt->remote_ip);
mod_delayed_work(amt_wq, &amt->req_wq, 0);
amt_update_gw_status(amt, AMT_STATUS_RECEIVED_ADVERTISEMENT, true);
return false;
}
static bool amt_multicast_data_handler(struct amt_dev *amt, struct sk_buff *skb)
{
struct amt_header_mcast_data *amtmd;
int hdr_size, len, err;
struct ethhdr *eth;
struct iphdr *iph;
if (READ_ONCE(amt->status) != AMT_STATUS_SENT_UPDATE)
return true;
hdr_size = sizeof(*amtmd) + sizeof(struct udphdr);
if (!pskb_may_pull(skb, hdr_size))
return true;
amtmd = (struct amt_header_mcast_data *)(udp_hdr(skb) + 1);
if (amtmd->reserved || amtmd->version)
return true;
if (iptunnel_pull_header(skb, hdr_size, htons(ETH_P_IP), false))
return true;
skb_reset_network_header(skb);
skb_push(skb, sizeof(*eth));
skb_reset_mac_header(skb);
skb_pull(skb, sizeof(*eth));
eth = eth_hdr(skb);
if (!pskb_may_pull(skb, sizeof(*iph)))
return true;
iph = ip_hdr(skb);
if (iph->version == 4) {
if (!ipv4_is_multicast(iph->daddr))
return true;
skb->protocol = htons(ETH_P_IP);
eth->h_proto = htons(ETH_P_IP);
ip_eth_mc_map(iph->daddr, eth->h_dest);
#if IS_ENABLED(CONFIG_IPV6)
} else if (iph->version == 6) {
struct ipv6hdr *ip6h;
if (!pskb_may_pull(skb, sizeof(*ip6h)))
return true;
ip6h = ipv6_hdr(skb);
if (!ipv6_addr_is_multicast(&ip6h->daddr))
return true;
skb->protocol = htons(ETH_P_IPV6);
eth->h_proto = htons(ETH_P_IPV6);
ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
#endif
} else {
return true;
}
skb->pkt_type = PACKET_MULTICAST;
skb->ip_summed = CHECKSUM_NONE;
len = skb->len;
err = gro_cells_receive(&amt->gro_cells, skb);
if (likely(err == NET_RX_SUCCESS))
dev_sw_netstats_rx_add(amt->dev, len);
else
amt->dev->stats.rx_dropped++;
return false;
}
static bool amt_membership_query_handler(struct amt_dev *amt,
struct sk_buff *skb)
{
struct amt_header_membership_query *amtmq;
struct igmpv3_query *ihv3;
struct ethhdr *eth, *oeth;
struct iphdr *iph;
int hdr_size, len;
hdr_size = sizeof(*amtmq) + sizeof(struct udphdr);
if (!pskb_may_pull(skb, hdr_size))
return true;
amtmq = (struct amt_header_membership_query *)(udp_hdr(skb) + 1);
if (amtmq->reserved || amtmq->version)
return true;
if (amtmq->nonce != amt->nonce)
return true;
hdr_size -= sizeof(*eth);
if (iptunnel_pull_header(skb, hdr_size, htons(ETH_P_TEB), false))
return true;
oeth = eth_hdr(skb);
skb_reset_mac_header(skb);
skb_pull(skb, sizeof(*eth));
skb_reset_network_header(skb);
eth = eth_hdr(skb);
if (!pskb_may_pull(skb, sizeof(*iph)))
return true;
iph = ip_hdr(skb);
if (iph->version == 4) {
if (READ_ONCE(amt->ready4))
return true;
if (!pskb_may_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS +
sizeof(*ihv3)))
return true;
if (!ipv4_is_multicast(iph->daddr))
return true;
ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
skb_reset_transport_header(skb);
skb_push(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
WRITE_ONCE(amt->ready4, true);
amt->mac = amtmq->response_mac;
amt->req_cnt = 0;
amt->qi = ihv3->qqic;
skb->protocol = htons(ETH_P_IP);
eth->h_proto = htons(ETH_P_IP);
ip_eth_mc_map(iph->daddr, eth->h_dest);
#if IS_ENABLED(CONFIG_IPV6)
} else if (iph->version == 6) {
struct mld2_query *mld2q;
struct ipv6hdr *ip6h;
if (READ_ONCE(amt->ready6))
return true;
if (!pskb_may_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS +
sizeof(*mld2q)))
return true;
ip6h = ipv6_hdr(skb);
if (!ipv6_addr_is_multicast(&ip6h->daddr))
return true;
mld2q = skb_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS);
skb_reset_transport_header(skb);
skb_push(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS);
WRITE_ONCE(amt->ready6, true);
amt->mac = amtmq->response_mac;
amt->req_cnt = 0;
amt->qi = mld2q->mld2q_qqic;
skb->protocol = htons(ETH_P_IPV6);
eth->h_proto = htons(ETH_P_IPV6);
ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
#endif
} else {
return true;
}
ether_addr_copy(eth->h_source, oeth->h_source);
skb->pkt_type = PACKET_MULTICAST;
skb->ip_summed = CHECKSUM_NONE;
len = skb->len;
local_bh_disable();
if (__netif_rx(skb) == NET_RX_SUCCESS) {
amt_update_gw_status(amt, AMT_STATUS_RECEIVED_QUERY, true);
dev_sw_netstats_rx_add(amt->dev, len);
} else {
amt->dev->stats.rx_dropped++;
}
local_bh_enable();
return false;
}
static bool amt_update_handler(struct amt_dev *amt, struct sk_buff *skb)
{
struct amt_header_membership_update *amtmu;
struct amt_tunnel_list *tunnel;
struct ethhdr *eth;
struct iphdr *iph;
int len, hdr_size;
iph = ip_hdr(skb);
hdr_size = sizeof(*amtmu) + sizeof(struct udphdr);
if (!pskb_may_pull(skb, hdr_size))
return true;
amtmu = (struct amt_header_membership_update *)(udp_hdr(skb) + 1);
if (amtmu->reserved || amtmu->version)
return true;
if (iptunnel_pull_header(skb, hdr_size, skb->protocol, false))
return true;
skb_reset_network_header(skb);
list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list) {
if (tunnel->ip4 == iph->saddr) {
if ((amtmu->nonce == tunnel->nonce &&
amtmu->response_mac == tunnel->mac)) {
mod_delayed_work(amt_wq, &tunnel->gc_wq,
msecs_to_jiffies(amt_gmi(amt))
* 3);
goto report;
} else {
netdev_dbg(amt->dev, "Invalid MAC\n");
return true;
}
}
}
return true;
report:
if (!pskb_may_pull(skb, sizeof(*iph)))
return true;
iph = ip_hdr(skb);
if (iph->version == 4) {
if (ip_mc_check_igmp(skb)) {
netdev_dbg(amt->dev, "Invalid IGMP\n");
return true;
}
spin_lock_bh(&tunnel->lock);
amt_igmp_report_handler(amt, skb, tunnel);
spin_unlock_bh(&tunnel->lock);
skb_push(skb, sizeof(struct ethhdr));
skb_reset_mac_header(skb);
eth = eth_hdr(skb);
skb->protocol = htons(ETH_P_IP);
eth->h_proto = htons(ETH_P_IP);
ip_eth_mc_map(iph->daddr, eth->h_dest);
#if IS_ENABLED(CONFIG_IPV6)
} else if (iph->version == 6) {
struct ipv6hdr *ip6h = ipv6_hdr(skb);
if (ipv6_mc_check_mld(skb)) {
netdev_dbg(amt->dev, "Invalid MLD\n");
return true;
}
spin_lock_bh(&tunnel->lock);
amt_mld_report_handler(amt, skb, tunnel);
spin_unlock_bh(&tunnel->lock);
skb_push(skb, sizeof(struct ethhdr));
skb_reset_mac_header(skb);
eth = eth_hdr(skb);
skb->protocol = htons(ETH_P_IPV6);
eth->h_proto = htons(ETH_P_IPV6);
ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
#endif
} else {
netdev_dbg(amt->dev, "Unsupported Protocol\n");
return true;
}
skb_pull(skb, sizeof(struct ethhdr));
skb->pkt_type = PACKET_MULTICAST;
skb->ip_summed = CHECKSUM_NONE;
len = skb->len;
if (__netif_rx(skb) == NET_RX_SUCCESS) {
amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_UPDATE,
true);
dev_sw_netstats_rx_add(amt->dev, len);
} else {
amt->dev->stats.rx_dropped++;
}
return false;
}
static void amt_send_advertisement(struct amt_dev *amt, __be32 nonce,
__be32 daddr, __be16 dport)
{
struct amt_header_advertisement *amta;
int hlen, tlen, offset;
struct socket *sock;
struct udphdr *udph;
struct sk_buff *skb;
struct iphdr *iph;
struct rtable *rt;
struct flowi4 fl4;
u32 len;
int err;
rcu_read_lock();
sock = rcu_dereference(amt->sock);
if (!sock)
goto out;
if (!netif_running(amt->stream_dev) || !netif_running(amt->dev))
goto out;
rt = ip_route_output_ports(amt->net, &fl4, sock->sk,
daddr, amt->local_ip,
dport, amt->relay_port,
IPPROTO_UDP, 0,
amt->stream_dev->ifindex);
if (IS_ERR(rt)) {
amt->dev->stats.tx_errors++;
goto out;
}
hlen = LL_RESERVED_SPACE(amt->dev);
tlen = amt->dev->needed_tailroom;
len = hlen + tlen + sizeof(*iph) + sizeof(*udph) + sizeof(*amta);
skb = netdev_alloc_skb_ip_align(amt->dev, len);
if (!skb) {
ip_rt_put(rt);
amt->dev->stats.tx_errors++;
goto out;
}
skb->priority = TC_PRIO_CONTROL;
skb_dst_set(skb, &rt->dst);
len = sizeof(*iph) + sizeof(*udph) + sizeof(*amta);
skb_reset_network_header(skb);
skb_put(skb, len);
amta = skb_pull(skb, sizeof(*iph) + sizeof(*udph));
amta->version = 0;
amta->type = AMT_MSG_ADVERTISEMENT;
amta->reserved = 0;
amta->nonce = nonce;
amta->ip4 = amt->local_ip;
skb_push(skb, sizeof(*udph));
skb_reset_transport_header(skb);
udph = udp_hdr(skb);
udph->source = amt->relay_port;
udph->dest = dport;
udph->len = htons(sizeof(*amta) + sizeof(*udph));
udph->check = 0;
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
udph->check = csum_tcpudp_magic(amt->local_ip, daddr,
sizeof(*udph) + sizeof(*amta),
IPPROTO_UDP, skb->csum);
skb_push(skb, sizeof(*iph));
iph = ip_hdr(skb);
iph->version = 4;
iph->ihl = (sizeof(struct iphdr)) >> 2;
iph->tos = AMT_TOS;
iph->frag_off = 0;
iph->ttl = ip4_dst_hoplimit(&rt->dst);
iph->daddr = daddr;
iph->saddr = amt->local_ip;
iph->protocol = IPPROTO_UDP;
iph->tot_len = htons(len);
skb->ip_summed = CHECKSUM_NONE;
ip_select_ident(amt->net, skb, NULL);
ip_send_check(iph);
err = ip_local_out(amt->net, sock->sk, skb);
if (unlikely(net_xmit_eval(err)))
amt->dev->stats.tx_errors++;
out:
rcu_read_unlock();
}
static bool amt_discovery_handler(struct amt_dev *amt, struct sk_buff *skb)
{
struct amt_header_discovery *amtd;
struct udphdr *udph;
struct iphdr *iph;
if (!pskb_may_pull(skb, sizeof(*udph) + sizeof(*amtd)))
return true;
iph = ip_hdr(skb);
udph = udp_hdr(skb);
amtd = (struct amt_header_discovery *)(udp_hdr(skb) + 1);
if (amtd->reserved || amtd->version)
return true;
amt_send_advertisement(amt, amtd->nonce, iph->saddr, udph->source);
return false;
}
static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb)
{
struct amt_header_request *amtrh;
struct amt_tunnel_list *tunnel;
unsigned long long key;
struct udphdr *udph;
struct iphdr *iph;
u64 mac;
int i;
if (!pskb_may_pull(skb, sizeof(*udph) + sizeof(*amtrh)))
return true;
iph = ip_hdr(skb);
udph = udp_hdr(skb);
amtrh = (struct amt_header_request *)(udp_hdr(skb) + 1);
if (amtrh->reserved1 || amtrh->reserved2 || amtrh->version)
return true;
list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list)
if (tunnel->ip4 == iph->saddr)
goto send;
spin_lock_bh(&amt->lock);
if (amt->nr_tunnels >= amt->max_tunnels) {
spin_unlock_bh(&amt->lock);
icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
return true;
}
tunnel = kzalloc(sizeof(*tunnel) +
(sizeof(struct hlist_head) * amt->hash_buckets),
GFP_ATOMIC);
if (!tunnel) {
spin_unlock_bh(&amt->lock);
return true;
}
tunnel->source_port = udph->source;
tunnel->ip4 = iph->saddr;
memcpy(&key, &tunnel->key, sizeof(unsigned long long));
tunnel->amt = amt;
spin_lock_init(&tunnel->lock);
for (i = 0; i < amt->hash_buckets; i++)
INIT_HLIST_HEAD(&tunnel->groups[i]);
INIT_DELAYED_WORK(&tunnel->gc_wq, amt_tunnel_expire);
list_add_tail_rcu(&tunnel->list, &amt->tunnel_list);
tunnel->key = amt->key;
__amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_REQUEST, true);
amt->nr_tunnels++;
mod_delayed_work(amt_wq, &tunnel->gc_wq,
msecs_to_jiffies(amt_gmi(amt)));
spin_unlock_bh(&amt->lock);
send:
tunnel->nonce = amtrh->nonce;
mac = siphash_3u32((__force u32)tunnel->ip4,
(__force u32)tunnel->source_port,
(__force u32)tunnel->nonce,
&tunnel->key);
tunnel->mac = mac >> 16;
if (!netif_running(amt->dev) || !netif_running(amt->stream_dev))
return true;
if (!amtrh->p)
amt_send_igmp_gq(amt, tunnel);
else
amt_send_mld_gq(amt, tunnel);
return false;
}
static void amt_gw_rcv(struct amt_dev *amt, struct sk_buff *skb)
{
int type = amt_parse_type(skb);
int err = 1;
if (type == -1)
goto drop;
if (amt->mode == AMT_MODE_GATEWAY) {
switch (type) {
case AMT_MSG_ADVERTISEMENT:
err = amt_advertisement_handler(amt, skb);
break;
case AMT_MSG_MEMBERSHIP_QUERY:
err = amt_membership_query_handler(amt, skb);
if (!err)
return;
break;
default:
netdev_dbg(amt->dev, "Invalid type of Gateway\n");
break;
}
}
drop:
if (err) {
amt->dev->stats.rx_dropped++;
kfree_skb(skb);
} else {
consume_skb(skb);
}
}
static int amt_rcv(struct sock *sk, struct sk_buff *skb)
{
struct amt_dev *amt;
struct iphdr *iph;
int type;
bool err;
rcu_read_lock_bh();
amt = rcu_dereference_sk_user_data(sk);
if (!amt) {
err = true;
kfree_skb(skb);
goto out;
}
skb->dev = amt->dev;
iph = ip_hdr(skb);
type = amt_parse_type(skb);
if (type == -1) {
err = true;
goto drop;
}
if (amt->mode == AMT_MODE_GATEWAY) {
switch (type) {
case AMT_MSG_ADVERTISEMENT:
if (iph->saddr != amt->discovery_ip) {
netdev_dbg(amt->dev, "Invalid Relay IP\n");
err = true;
goto drop;
}
if (amt_queue_event(amt, AMT_EVENT_RECEIVE, skb)) {
netdev_dbg(amt->dev, "AMT Event queue full\n");
err = true;
goto drop;
}
goto out;
case AMT_MSG_MULTICAST_DATA:
if (iph->saddr != amt->remote_ip) {
netdev_dbg(amt->dev, "Invalid Relay IP\n");
err = true;
goto drop;
}
err = amt_multicast_data_handler(amt, skb);
if (err)
goto drop;
else
goto out;
case AMT_MSG_MEMBERSHIP_QUERY:
if (iph->saddr != amt->remote_ip) {
netdev_dbg(amt->dev, "Invalid Relay IP\n");
err = true;
goto drop;
}
if (amt_queue_event(amt, AMT_EVENT_RECEIVE, skb)) {
netdev_dbg(amt->dev, "AMT Event queue full\n");
err = true;
goto drop;
}
goto out;
default:
err = true;
netdev_dbg(amt->dev, "Invalid type of Gateway\n");
break;
}
} else {
switch (type) {
case AMT_MSG_DISCOVERY:
err = amt_discovery_handler(amt, skb);
break;
case AMT_MSG_REQUEST:
err = amt_request_handler(amt, skb);
break;
case AMT_MSG_MEMBERSHIP_UPDATE:
err = amt_update_handler(amt, skb);
if (err)
goto drop;
else
goto out;
default:
err = true;
netdev_dbg(amt->dev, "Invalid type of relay\n");
break;
}
}
drop:
if (err) {
amt->dev->stats.rx_dropped++;
kfree_skb(skb);
} else {
consume_skb(skb);
}
out:
rcu_read_unlock_bh();
return 0;
}
static void amt_event_work(struct work_struct *work)
{
struct amt_dev *amt = container_of(work, struct amt_dev, event_wq);
struct sk_buff *skb;
u8 event;
int i;
for (i = 0; i < AMT_MAX_EVENTS; i++) {
spin_lock_bh(&amt->lock);
if (amt->nr_events == 0) {
spin_unlock_bh(&amt->lock);
return;
}
event = amt->events[amt->event_idx].event;
skb = amt->events[amt->event_idx].skb;
amt->events[amt->event_idx].event = AMT_EVENT_NONE;
amt->events[amt->event_idx].skb = NULL;
amt->nr_events--;
amt->event_idx++;
amt->event_idx %= AMT_MAX_EVENTS;
spin_unlock_bh(&amt->lock);
switch (event) {
case AMT_EVENT_RECEIVE:
amt_gw_rcv(amt, skb);
break;
case AMT_EVENT_SEND_DISCOVERY:
amt_event_send_discovery(amt);
break;
case AMT_EVENT_SEND_REQUEST:
amt_event_send_request(amt);
break;
default:
kfree_skb(skb);
break;
}
}
}
static int amt_err_lookup(struct sock *sk, struct sk_buff *skb)
{
struct amt_dev *amt;
int type;
rcu_read_lock_bh();
amt = rcu_dereference_sk_user_data(sk);
if (!amt)
goto out;
if (amt->mode != AMT_MODE_GATEWAY)
goto drop;
type = amt_parse_type(skb);
if (type == -1)
goto drop;
netdev_dbg(amt->dev, "Received IGMP Unreachable of %s\n",
type_str[type]);
switch (type) {
case AMT_MSG_DISCOVERY:
break;
case AMT_MSG_REQUEST:
case AMT_MSG_MEMBERSHIP_UPDATE:
if (READ_ONCE(amt->status) >= AMT_STATUS_RECEIVED_ADVERTISEMENT)
mod_delayed_work(amt_wq, &amt->req_wq, 0);
break;
default:
goto drop;
}
out:
rcu_read_unlock_bh();
return 0;
drop:
rcu_read_unlock_bh();
amt->dev->stats.rx_dropped++;
return 0;
}
static struct socket *amt_create_sock(struct net *net, __be16 port)
{
struct udp_port_cfg udp_conf;
struct socket *sock;
int err;
memset(&udp_conf, 0, sizeof(udp_conf));
udp_conf.family = AF_INET;
udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
udp_conf.local_udp_port = port;
err = udp_sock_create(net, &udp_conf, &sock);
if (err < 0)
return ERR_PTR(err);
return sock;
}
static int amt_socket_create(struct amt_dev *amt)
{
struct udp_tunnel_sock_cfg tunnel_cfg;
struct socket *sock;
sock = amt_create_sock(amt->net, amt->relay_port);
if (IS_ERR(sock))
return PTR_ERR(sock);
/* Mark socket as an encapsulation socket */
memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
tunnel_cfg.sk_user_data = amt;
tunnel_cfg.encap_type = 1;
tunnel_cfg.encap_rcv = amt_rcv;
tunnel_cfg.encap_err_lookup = amt_err_lookup;
tunnel_cfg.encap_destroy = NULL;
setup_udp_tunnel_sock(amt->net, sock, &tunnel_cfg);
rcu_assign_pointer(amt->sock, sock);
return 0;
}
static int amt_dev_open(struct net_device *dev)
{
struct amt_dev *amt = netdev_priv(dev);
int err;
amt->ready4 = false;
amt->ready6 = false;
amt->event_idx = 0;
amt->nr_events = 0;
err = amt_socket_create(amt);
if (err)
return err;
amt->req_cnt = 0;
amt->remote_ip = 0;
amt->nonce = 0;
get_random_bytes(&amt->key, sizeof(siphash_key_t));
amt->status = AMT_STATUS_INIT;
if (amt->mode == AMT_MODE_GATEWAY) {
mod_delayed_work(amt_wq, &amt->discovery_wq, 0);
mod_delayed_work(amt_wq, &amt->req_wq, 0);
} else if (amt->mode == AMT_MODE_RELAY) {
mod_delayed_work(amt_wq, &amt->secret_wq,
msecs_to_jiffies(AMT_SECRET_TIMEOUT));
}
return err;
}
static int amt_dev_stop(struct net_device *dev)
{
struct amt_dev *amt = netdev_priv(dev);
struct amt_tunnel_list *tunnel, *tmp;
struct socket *sock;
struct sk_buff *skb;
int i;
cancel_delayed_work_sync(&amt->req_wq);
cancel_delayed_work_sync(&amt->discovery_wq);
cancel_delayed_work_sync(&amt->secret_wq);
/* shutdown */
sock = rtnl_dereference(amt->sock);
RCU_INIT_POINTER(amt->sock, NULL);
synchronize_net();
if (sock)
udp_tunnel_sock_release(sock);
cancel_work_sync(&amt->event_wq);
for (i = 0; i < AMT_MAX_EVENTS; i++) {
skb = amt->events[i].skb;
kfree_skb(skb);
amt->events[i].event = AMT_EVENT_NONE;
amt->events[i].skb = NULL;
}
amt->ready4 = false;
amt->ready6 = false;
amt->req_cnt = 0;
amt->remote_ip = 0;
list_for_each_entry_safe(tunnel, tmp, &amt->tunnel_list, list) {
list_del_rcu(&tunnel->list);
amt->nr_tunnels--;
cancel_delayed_work_sync(&tunnel->gc_wq);
amt_clear_groups(tunnel);
kfree_rcu(tunnel, rcu);
}
return 0;
}
static const struct device_type amt_type = {
.name = "amt",
};
static int amt_dev_init(struct net_device *dev)
{
struct amt_dev *amt = netdev_priv(dev);
int err;
amt->dev = dev;
dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
if (!dev->tstats)
return -ENOMEM;
err = gro_cells_init(&amt->gro_cells, dev);
if (err) {
free_percpu(dev->tstats);
return err;
}
return 0;
}
static void amt_dev_uninit(struct net_device *dev)
{
struct amt_dev *amt = netdev_priv(dev);
gro_cells_destroy(&amt->gro_cells);
free_percpu(dev->tstats);
}
static const struct net_device_ops amt_netdev_ops = {
.ndo_init = amt_dev_init,
.ndo_uninit = amt_dev_uninit,
.ndo_open = amt_dev_open,
.ndo_stop = amt_dev_stop,
.ndo_start_xmit = amt_dev_xmit,
.ndo_get_stats64 = dev_get_tstats64,
};
static void amt_link_setup(struct net_device *dev)
{
dev->netdev_ops = &amt_netdev_ops;
dev->needs_free_netdev = true;
SET_NETDEV_DEVTYPE(dev, &amt_type);
dev->min_mtu = ETH_MIN_MTU;
dev->max_mtu = ETH_MAX_MTU;
dev->type = ARPHRD_NONE;
dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
dev->hard_header_len = 0;
dev->addr_len = 0;
dev->priv_flags |= IFF_NO_QUEUE;
dev->features |= NETIF_F_LLTX;
dev->features |= NETIF_F_GSO_SOFTWARE;
dev->features |= NETIF_F_NETNS_LOCAL;
dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM;
dev->hw_features |= NETIF_F_FRAGLIST | NETIF_F_RXCSUM;
dev->hw_features |= NETIF_F_GSO_SOFTWARE;
eth_hw_addr_random(dev);
eth_zero_addr(dev->broadcast);
ether_setup(dev);
}
static const struct nla_policy amt_policy[IFLA_AMT_MAX + 1] = {
[IFLA_AMT_MODE] = { .type = NLA_U32 },
[IFLA_AMT_RELAY_PORT] = { .type = NLA_U16 },
[IFLA_AMT_GATEWAY_PORT] = { .type = NLA_U16 },
[IFLA_AMT_LINK] = { .type = NLA_U32 },
[IFLA_AMT_LOCAL_IP] = { .len = sizeof_field(struct iphdr, daddr) },
[IFLA_AMT_REMOTE_IP] = { .len = sizeof_field(struct iphdr, daddr) },
[IFLA_AMT_DISCOVERY_IP] = { .len = sizeof_field(struct iphdr, daddr) },
[IFLA_AMT_MAX_TUNNELS] = { .type = NLA_U32 },
};
static int amt_validate(struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
if (!data)
return -EINVAL;
if (!data[IFLA_AMT_LINK]) {
NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_LINK],
"Link attribute is required");
return -EINVAL;
}
if (!data[IFLA_AMT_MODE]) {
NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_MODE],
"Mode attribute is required");
return -EINVAL;
}
if (nla_get_u32(data[IFLA_AMT_MODE]) > AMT_MODE_MAX) {
NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_MODE],
"Mode attribute is not valid");
return -EINVAL;
}
if (!data[IFLA_AMT_LOCAL_IP]) {
NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_DISCOVERY_IP],
"Local attribute is required");
return -EINVAL;
}
if (!data[IFLA_AMT_DISCOVERY_IP] &&
nla_get_u32(data[IFLA_AMT_MODE]) == AMT_MODE_GATEWAY) {
NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_LOCAL_IP],
"Discovery attribute is required");
return -EINVAL;
}
return 0;
}
static int amt_newlink(struct net *net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct amt_dev *amt = netdev_priv(dev);
int err = -EINVAL;
amt->net = net;
amt->mode = nla_get_u32(data[IFLA_AMT_MODE]);
if (data[IFLA_AMT_MAX_TUNNELS] &&
nla_get_u32(data[IFLA_AMT_MAX_TUNNELS]))
amt->max_tunnels = nla_get_u32(data[IFLA_AMT_MAX_TUNNELS]);
else
amt->max_tunnels = AMT_MAX_TUNNELS;
spin_lock_init(&amt->lock);
amt->max_groups = AMT_MAX_GROUP;
amt->max_sources = AMT_MAX_SOURCE;
amt->hash_buckets = AMT_HSIZE;
amt->nr_tunnels = 0;
get_random_bytes(&amt->hash_seed, sizeof(amt->hash_seed));
amt->stream_dev = dev_get_by_index(net,
nla_get_u32(data[IFLA_AMT_LINK]));
if (!amt->stream_dev) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LINK],
"Can't find stream device");
return -ENODEV;
}
if (amt->stream_dev->type != ARPHRD_ETHER) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LINK],
"Invalid stream device type");
goto err;
}
amt->local_ip = nla_get_in_addr(data[IFLA_AMT_LOCAL_IP]);
if (ipv4_is_loopback(amt->local_ip) ||
ipv4_is_zeronet(amt->local_ip) ||
ipv4_is_multicast(amt->local_ip)) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LOCAL_IP],
"Invalid Local address");
goto err;
}
if (data[IFLA_AMT_RELAY_PORT])
amt->relay_port = nla_get_be16(data[IFLA_AMT_RELAY_PORT]);
else
amt->relay_port = htons(IANA_AMT_UDP_PORT);
if (data[IFLA_AMT_GATEWAY_PORT])
amt->gw_port = nla_get_be16(data[IFLA_AMT_GATEWAY_PORT]);
else
amt->gw_port = htons(IANA_AMT_UDP_PORT);
if (!amt->relay_port) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP],
"relay port must not be 0");
goto err;
}
if (amt->mode == AMT_MODE_RELAY) {
amt->qrv = READ_ONCE(amt->net->ipv4.sysctl_igmp_qrv);
amt->qri = 10;
dev->needed_headroom = amt->stream_dev->needed_headroom +
AMT_RELAY_HLEN;
dev->mtu = amt->stream_dev->mtu - AMT_RELAY_HLEN;
dev->max_mtu = dev->mtu;
dev->min_mtu = ETH_MIN_MTU + AMT_RELAY_HLEN;
} else {
if (!data[IFLA_AMT_DISCOVERY_IP]) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP],
"discovery must be set in gateway mode");
goto err;
}
if (!amt->gw_port) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP],
"gateway port must not be 0");
goto err;
}
amt->remote_ip = 0;
amt->discovery_ip = nla_get_in_addr(data[IFLA_AMT_DISCOVERY_IP]);
if (ipv4_is_loopback(amt->discovery_ip) ||
ipv4_is_zeronet(amt->discovery_ip) ||
ipv4_is_multicast(amt->discovery_ip)) {
NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP],
"discovery must be unicast");
goto err;
}
dev->needed_headroom = amt->stream_dev->needed_headroom +
AMT_GW_HLEN;
dev->mtu = amt->stream_dev->mtu - AMT_GW_HLEN;
dev->max_mtu = dev->mtu;
dev->min_mtu = ETH_MIN_MTU + AMT_GW_HLEN;
}
amt->qi = AMT_INIT_QUERY_INTERVAL;
err = register_netdevice(dev);
if (err < 0) {
netdev_dbg(dev, "failed to register new netdev %d\n", err);
goto err;
}
err = netdev_upper_dev_link(amt->stream_dev, dev, extack);
if (err < 0) {
unregister_netdevice(dev);
goto err;
}
INIT_DELAYED_WORK(&amt->discovery_wq, amt_discovery_work);
INIT_DELAYED_WORK(&amt->req_wq, amt_req_work);
INIT_DELAYED_WORK(&amt->secret_wq, amt_secret_work);
INIT_WORK(&amt->event_wq, amt_event_work);
INIT_LIST_HEAD(&amt->tunnel_list);
return 0;
err:
dev_put(amt->stream_dev);
return err;
}
static void amt_dellink(struct net_device *dev, struct list_head *head)
{
struct amt_dev *amt = netdev_priv(dev);
unregister_netdevice_queue(dev, head);
netdev_upper_dev_unlink(amt->stream_dev, dev);
dev_put(amt->stream_dev);
}
static size_t amt_get_size(const struct net_device *dev)
{
return nla_total_size(sizeof(__u32)) + /* IFLA_AMT_MODE */
nla_total_size(sizeof(__u16)) + /* IFLA_AMT_RELAY_PORT */
nla_total_size(sizeof(__u16)) + /* IFLA_AMT_GATEWAY_PORT */
nla_total_size(sizeof(__u32)) + /* IFLA_AMT_LINK */
nla_total_size(sizeof(__u32)) + /* IFLA_MAX_TUNNELS */
nla_total_size(sizeof(struct iphdr)) + /* IFLA_AMT_DISCOVERY_IP */
nla_total_size(sizeof(struct iphdr)) + /* IFLA_AMT_REMOTE_IP */
nla_total_size(sizeof(struct iphdr)); /* IFLA_AMT_LOCAL_IP */
}
static int amt_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct amt_dev *amt = netdev_priv(dev);
if (nla_put_u32(skb, IFLA_AMT_MODE, amt->mode))
goto nla_put_failure;
if (nla_put_be16(skb, IFLA_AMT_RELAY_PORT, amt->relay_port))
goto nla_put_failure;
if (nla_put_be16(skb, IFLA_AMT_GATEWAY_PORT, amt->gw_port))
goto nla_put_failure;
if (nla_put_u32(skb, IFLA_AMT_LINK, amt->stream_dev->ifindex))
goto nla_put_failure;
if (nla_put_in_addr(skb, IFLA_AMT_LOCAL_IP, amt->local_ip))
goto nla_put_failure;
if (nla_put_in_addr(skb, IFLA_AMT_DISCOVERY_IP, amt->discovery_ip))
goto nla_put_failure;
if (amt->remote_ip)
if (nla_put_in_addr(skb, IFLA_AMT_REMOTE_IP, amt->remote_ip))
goto nla_put_failure;
if (nla_put_u32(skb, IFLA_AMT_MAX_TUNNELS, amt->max_tunnels))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
static struct rtnl_link_ops amt_link_ops __read_mostly = {
.kind = "amt",
.maxtype = IFLA_AMT_MAX,
.policy = amt_policy,
.priv_size = sizeof(struct amt_dev),
.setup = amt_link_setup,
.validate = amt_validate,
.newlink = amt_newlink,
.dellink = amt_dellink,
.get_size = amt_get_size,
.fill_info = amt_fill_info,
};
static struct net_device *amt_lookup_upper_dev(struct net_device *dev)
{
struct net_device *upper_dev;
struct amt_dev *amt;
for_each_netdev(dev_net(dev), upper_dev) {
if (netif_is_amt(upper_dev)) {
amt = netdev_priv(upper_dev);
if (amt->stream_dev == dev)
return upper_dev;
}
}
return NULL;
}
static int amt_device_event(struct notifier_block *unused,
unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct net_device *upper_dev;
struct amt_dev *amt;
LIST_HEAD(list);
int new_mtu;
upper_dev = amt_lookup_upper_dev(dev);
if (!upper_dev)
return NOTIFY_DONE;
amt = netdev_priv(upper_dev);
switch (event) {
case NETDEV_UNREGISTER:
amt_dellink(amt->dev, &list);
unregister_netdevice_many(&list);
break;
case NETDEV_CHANGEMTU:
if (amt->mode == AMT_MODE_RELAY)
new_mtu = dev->mtu - AMT_RELAY_HLEN;
else
new_mtu = dev->mtu - AMT_GW_HLEN;
dev_set_mtu(amt->dev, new_mtu);
break;
}
return NOTIFY_DONE;
}
static struct notifier_block amt_notifier_block __read_mostly = {
.notifier_call = amt_device_event,
};
static int __init amt_init(void)
{
int err;
err = register_netdevice_notifier(&amt_notifier_block);
if (err < 0)
goto err;
err = rtnl_link_register(&amt_link_ops);
if (err < 0)
goto unregister_notifier;
amt_wq = alloc_workqueue("amt", WQ_UNBOUND, 0);
if (!amt_wq) {
err = -ENOMEM;
goto rtnl_unregister;
}
spin_lock_init(&source_gc_lock);
spin_lock_bh(&source_gc_lock);
INIT_DELAYED_WORK(&source_gc_wq, amt_source_gc_work);
mod_delayed_work(amt_wq, &source_gc_wq,
msecs_to_jiffies(AMT_GC_INTERVAL));
spin_unlock_bh(&source_gc_lock);
return 0;
rtnl_unregister:
rtnl_link_unregister(&amt_link_ops);
unregister_notifier:
unregister_netdevice_notifier(&amt_notifier_block);
err:
pr_err("error loading AMT module loaded\n");
return err;
}
late_initcall(amt_init);
static void __exit amt_fini(void)
{
rtnl_link_unregister(&amt_link_ops);
unregister_netdevice_notifier(&amt_notifier_block);
cancel_delayed_work_sync(&source_gc_wq);
__amt_source_gc_work();
destroy_workqueue(amt_wq);
}
module_exit(amt_fini);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Driver for Automatic Multicast Tunneling (AMT)");
MODULE_AUTHOR("Taehee Yoo <ap420073@gmail.com>");
MODULE_ALIAS_RTNL_LINK("amt");