658 lines
14 KiB
C
658 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/jhash.h>
|
|
#include <linux/netfilter.h>
|
|
#include <linux/rcupdate.h>
|
|
#include <linux/rhashtable.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <net/genetlink.h>
|
|
#include <net/ila.h>
|
|
#include <net/netns/generic.h>
|
|
#include <uapi/linux/genetlink.h>
|
|
#include "ila.h"
|
|
|
|
struct ila_xlat_params {
|
|
struct ila_params ip;
|
|
int ifindex;
|
|
};
|
|
|
|
struct ila_map {
|
|
struct ila_xlat_params xp;
|
|
struct rhash_head node;
|
|
struct ila_map __rcu *next;
|
|
struct rcu_head rcu;
|
|
};
|
|
|
|
#define MAX_LOCKS 1024
|
|
#define LOCKS_PER_CPU 10
|
|
|
|
static int alloc_ila_locks(struct ila_net *ilan)
|
|
{
|
|
return alloc_bucket_spinlocks(&ilan->xlat.locks, &ilan->xlat.locks_mask,
|
|
MAX_LOCKS, LOCKS_PER_CPU,
|
|
GFP_KERNEL);
|
|
}
|
|
|
|
static u32 hashrnd __read_mostly;
|
|
static __always_inline void __ila_hash_secret_init(void)
|
|
{
|
|
net_get_random_once(&hashrnd, sizeof(hashrnd));
|
|
}
|
|
|
|
static inline u32 ila_locator_hash(struct ila_locator loc)
|
|
{
|
|
u32 *v = (u32 *)loc.v32;
|
|
|
|
__ila_hash_secret_init();
|
|
return jhash_2words(v[0], v[1], hashrnd);
|
|
}
|
|
|
|
static inline spinlock_t *ila_get_lock(struct ila_net *ilan,
|
|
struct ila_locator loc)
|
|
{
|
|
return &ilan->xlat.locks[ila_locator_hash(loc) & ilan->xlat.locks_mask];
|
|
}
|
|
|
|
static inline int ila_cmp_wildcards(struct ila_map *ila,
|
|
struct ila_addr *iaddr, int ifindex)
|
|
{
|
|
return (ila->xp.ifindex && ila->xp.ifindex != ifindex);
|
|
}
|
|
|
|
static inline int ila_cmp_params(struct ila_map *ila,
|
|
struct ila_xlat_params *xp)
|
|
{
|
|
return (ila->xp.ifindex != xp->ifindex);
|
|
}
|
|
|
|
static int ila_cmpfn(struct rhashtable_compare_arg *arg,
|
|
const void *obj)
|
|
{
|
|
const struct ila_map *ila = obj;
|
|
|
|
return (ila->xp.ip.locator_match.v64 != *(__be64 *)arg->key);
|
|
}
|
|
|
|
static inline int ila_order(struct ila_map *ila)
|
|
{
|
|
int score = 0;
|
|
|
|
if (ila->xp.ifindex)
|
|
score += 1 << 1;
|
|
|
|
return score;
|
|
}
|
|
|
|
static const struct rhashtable_params rht_params = {
|
|
.nelem_hint = 1024,
|
|
.head_offset = offsetof(struct ila_map, node),
|
|
.key_offset = offsetof(struct ila_map, xp.ip.locator_match),
|
|
.key_len = sizeof(u64), /* identifier */
|
|
.max_size = 1048576,
|
|
.min_size = 256,
|
|
.automatic_shrinking = true,
|
|
.obj_cmpfn = ila_cmpfn,
|
|
};
|
|
|
|
static int parse_nl_config(struct genl_info *info,
|
|
struct ila_xlat_params *xp)
|
|
{
|
|
memset(xp, 0, sizeof(*xp));
|
|
|
|
if (info->attrs[ILA_ATTR_LOCATOR])
|
|
xp->ip.locator.v64 = (__force __be64)nla_get_u64(
|
|
info->attrs[ILA_ATTR_LOCATOR]);
|
|
|
|
if (info->attrs[ILA_ATTR_LOCATOR_MATCH])
|
|
xp->ip.locator_match.v64 = (__force __be64)nla_get_u64(
|
|
info->attrs[ILA_ATTR_LOCATOR_MATCH]);
|
|
|
|
if (info->attrs[ILA_ATTR_CSUM_MODE])
|
|
xp->ip.csum_mode = nla_get_u8(info->attrs[ILA_ATTR_CSUM_MODE]);
|
|
else
|
|
xp->ip.csum_mode = ILA_CSUM_NO_ACTION;
|
|
|
|
if (info->attrs[ILA_ATTR_IDENT_TYPE])
|
|
xp->ip.ident_type = nla_get_u8(
|
|
info->attrs[ILA_ATTR_IDENT_TYPE]);
|
|
else
|
|
xp->ip.ident_type = ILA_ATYPE_USE_FORMAT;
|
|
|
|
if (info->attrs[ILA_ATTR_IFINDEX])
|
|
xp->ifindex = nla_get_s32(info->attrs[ILA_ATTR_IFINDEX]);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Must be called with rcu readlock */
|
|
static inline struct ila_map *ila_lookup_wildcards(struct ila_addr *iaddr,
|
|
int ifindex,
|
|
struct ila_net *ilan)
|
|
{
|
|
struct ila_map *ila;
|
|
|
|
ila = rhashtable_lookup_fast(&ilan->xlat.rhash_table, &iaddr->loc,
|
|
rht_params);
|
|
while (ila) {
|
|
if (!ila_cmp_wildcards(ila, iaddr, ifindex))
|
|
return ila;
|
|
ila = rcu_access_pointer(ila->next);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/* Must be called with rcu readlock */
|
|
static inline struct ila_map *ila_lookup_by_params(struct ila_xlat_params *xp,
|
|
struct ila_net *ilan)
|
|
{
|
|
struct ila_map *ila;
|
|
|
|
ila = rhashtable_lookup_fast(&ilan->xlat.rhash_table,
|
|
&xp->ip.locator_match,
|
|
rht_params);
|
|
while (ila) {
|
|
if (!ila_cmp_params(ila, xp))
|
|
return ila;
|
|
ila = rcu_access_pointer(ila->next);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static inline void ila_release(struct ila_map *ila)
|
|
{
|
|
kfree_rcu(ila, rcu);
|
|
}
|
|
|
|
static void ila_free_node(struct ila_map *ila)
|
|
{
|
|
struct ila_map *next;
|
|
|
|
/* Assume rcu_readlock held */
|
|
while (ila) {
|
|
next = rcu_access_pointer(ila->next);
|
|
ila_release(ila);
|
|
ila = next;
|
|
}
|
|
}
|
|
|
|
static void ila_free_cb(void *ptr, void *arg)
|
|
{
|
|
ila_free_node((struct ila_map *)ptr);
|
|
}
|
|
|
|
static int ila_xlat_addr(struct sk_buff *skb, bool sir2ila);
|
|
|
|
static unsigned int
|
|
ila_nf_input(void *priv,
|
|
struct sk_buff *skb,
|
|
const struct nf_hook_state *state)
|
|
{
|
|
ila_xlat_addr(skb, false);
|
|
return NF_ACCEPT;
|
|
}
|
|
|
|
static const struct nf_hook_ops ila_nf_hook_ops[] = {
|
|
{
|
|
.hook = ila_nf_input,
|
|
.pf = NFPROTO_IPV6,
|
|
.hooknum = NF_INET_PRE_ROUTING,
|
|
.priority = -1,
|
|
},
|
|
};
|
|
|
|
static int ila_add_mapping(struct net *net, struct ila_xlat_params *xp)
|
|
{
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
struct ila_map *ila, *head;
|
|
spinlock_t *lock = ila_get_lock(ilan, xp->ip.locator_match);
|
|
int err = 0, order;
|
|
|
|
if (!ilan->xlat.hooks_registered) {
|
|
/* We defer registering net hooks in the namespace until the
|
|
* first mapping is added.
|
|
*/
|
|
err = nf_register_net_hooks(net, ila_nf_hook_ops,
|
|
ARRAY_SIZE(ila_nf_hook_ops));
|
|
if (err)
|
|
return err;
|
|
|
|
ilan->xlat.hooks_registered = true;
|
|
}
|
|
|
|
ila = kzalloc(sizeof(*ila), GFP_KERNEL);
|
|
if (!ila)
|
|
return -ENOMEM;
|
|
|
|
ila_init_saved_csum(&xp->ip);
|
|
|
|
ila->xp = *xp;
|
|
|
|
order = ila_order(ila);
|
|
|
|
spin_lock(lock);
|
|
|
|
head = rhashtable_lookup_fast(&ilan->xlat.rhash_table,
|
|
&xp->ip.locator_match,
|
|
rht_params);
|
|
if (!head) {
|
|
/* New entry for the rhash_table */
|
|
err = rhashtable_lookup_insert_fast(&ilan->xlat.rhash_table,
|
|
&ila->node, rht_params);
|
|
} else {
|
|
struct ila_map *tila = head, *prev = NULL;
|
|
|
|
do {
|
|
if (!ila_cmp_params(tila, xp)) {
|
|
err = -EEXIST;
|
|
goto out;
|
|
}
|
|
|
|
if (order > ila_order(tila))
|
|
break;
|
|
|
|
prev = tila;
|
|
tila = rcu_dereference_protected(tila->next,
|
|
lockdep_is_held(lock));
|
|
} while (tila);
|
|
|
|
if (prev) {
|
|
/* Insert in sub list of head */
|
|
RCU_INIT_POINTER(ila->next, tila);
|
|
rcu_assign_pointer(prev->next, ila);
|
|
} else {
|
|
/* Make this ila new head */
|
|
RCU_INIT_POINTER(ila->next, head);
|
|
err = rhashtable_replace_fast(&ilan->xlat.rhash_table,
|
|
&head->node,
|
|
&ila->node, rht_params);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
out:
|
|
spin_unlock(lock);
|
|
|
|
if (err)
|
|
kfree(ila);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int ila_del_mapping(struct net *net, struct ila_xlat_params *xp)
|
|
{
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
struct ila_map *ila, *head, *prev;
|
|
spinlock_t *lock = ila_get_lock(ilan, xp->ip.locator_match);
|
|
int err = -ENOENT;
|
|
|
|
spin_lock(lock);
|
|
|
|
head = rhashtable_lookup_fast(&ilan->xlat.rhash_table,
|
|
&xp->ip.locator_match, rht_params);
|
|
ila = head;
|
|
|
|
prev = NULL;
|
|
|
|
while (ila) {
|
|
if (ila_cmp_params(ila, xp)) {
|
|
prev = ila;
|
|
ila = rcu_dereference_protected(ila->next,
|
|
lockdep_is_held(lock));
|
|
continue;
|
|
}
|
|
|
|
err = 0;
|
|
|
|
if (prev) {
|
|
/* Not head, just delete from list */
|
|
rcu_assign_pointer(prev->next, ila->next);
|
|
} else {
|
|
/* It is the head. If there is something in the
|
|
* sublist we need to make a new head.
|
|
*/
|
|
head = rcu_dereference_protected(ila->next,
|
|
lockdep_is_held(lock));
|
|
if (head) {
|
|
/* Put first entry in the sublist into the
|
|
* table
|
|
*/
|
|
err = rhashtable_replace_fast(
|
|
&ilan->xlat.rhash_table, &ila->node,
|
|
&head->node, rht_params);
|
|
if (err)
|
|
goto out;
|
|
} else {
|
|
/* Entry no longer used */
|
|
err = rhashtable_remove_fast(
|
|
&ilan->xlat.rhash_table,
|
|
&ila->node, rht_params);
|
|
}
|
|
}
|
|
|
|
ila_release(ila);
|
|
|
|
break;
|
|
}
|
|
|
|
out:
|
|
spin_unlock(lock);
|
|
|
|
return err;
|
|
}
|
|
|
|
int ila_xlat_nl_cmd_add_mapping(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net *net = genl_info_net(info);
|
|
struct ila_xlat_params p;
|
|
int err;
|
|
|
|
err = parse_nl_config(info, &p);
|
|
if (err)
|
|
return err;
|
|
|
|
return ila_add_mapping(net, &p);
|
|
}
|
|
|
|
int ila_xlat_nl_cmd_del_mapping(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net *net = genl_info_net(info);
|
|
struct ila_xlat_params xp;
|
|
int err;
|
|
|
|
err = parse_nl_config(info, &xp);
|
|
if (err)
|
|
return err;
|
|
|
|
ila_del_mapping(net, &xp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline spinlock_t *lock_from_ila_map(struct ila_net *ilan,
|
|
struct ila_map *ila)
|
|
{
|
|
return ila_get_lock(ilan, ila->xp.ip.locator_match);
|
|
}
|
|
|
|
int ila_xlat_nl_cmd_flush(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net *net = genl_info_net(info);
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
struct rhashtable_iter iter;
|
|
struct ila_map *ila;
|
|
spinlock_t *lock;
|
|
int ret = 0;
|
|
|
|
rhashtable_walk_enter(&ilan->xlat.rhash_table, &iter);
|
|
rhashtable_walk_start(&iter);
|
|
|
|
for (;;) {
|
|
ila = rhashtable_walk_next(&iter);
|
|
|
|
if (IS_ERR(ila)) {
|
|
if (PTR_ERR(ila) == -EAGAIN)
|
|
continue;
|
|
ret = PTR_ERR(ila);
|
|
goto done;
|
|
} else if (!ila) {
|
|
break;
|
|
}
|
|
|
|
lock = lock_from_ila_map(ilan, ila);
|
|
|
|
spin_lock(lock);
|
|
|
|
ret = rhashtable_remove_fast(&ilan->xlat.rhash_table,
|
|
&ila->node, rht_params);
|
|
if (!ret)
|
|
ila_free_node(ila);
|
|
|
|
spin_unlock(lock);
|
|
|
|
if (ret)
|
|
break;
|
|
}
|
|
|
|
done:
|
|
rhashtable_walk_stop(&iter);
|
|
rhashtable_walk_exit(&iter);
|
|
return ret;
|
|
}
|
|
|
|
static int ila_fill_info(struct ila_map *ila, struct sk_buff *msg)
|
|
{
|
|
if (nla_put_u64_64bit(msg, ILA_ATTR_LOCATOR,
|
|
(__force u64)ila->xp.ip.locator.v64,
|
|
ILA_ATTR_PAD) ||
|
|
nla_put_u64_64bit(msg, ILA_ATTR_LOCATOR_MATCH,
|
|
(__force u64)ila->xp.ip.locator_match.v64,
|
|
ILA_ATTR_PAD) ||
|
|
nla_put_s32(msg, ILA_ATTR_IFINDEX, ila->xp.ifindex) ||
|
|
nla_put_u8(msg, ILA_ATTR_CSUM_MODE, ila->xp.ip.csum_mode) ||
|
|
nla_put_u8(msg, ILA_ATTR_IDENT_TYPE, ila->xp.ip.ident_type))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ila_dump_info(struct ila_map *ila,
|
|
u32 portid, u32 seq, u32 flags,
|
|
struct sk_buff *skb, u8 cmd)
|
|
{
|
|
void *hdr;
|
|
|
|
hdr = genlmsg_put(skb, portid, seq, &ila_nl_family, flags, cmd);
|
|
if (!hdr)
|
|
return -ENOMEM;
|
|
|
|
if (ila_fill_info(ila, skb) < 0)
|
|
goto nla_put_failure;
|
|
|
|
genlmsg_end(skb, hdr);
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
genlmsg_cancel(skb, hdr);
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
int ila_xlat_nl_cmd_get_mapping(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net *net = genl_info_net(info);
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
struct sk_buff *msg;
|
|
struct ila_xlat_params xp;
|
|
struct ila_map *ila;
|
|
int ret;
|
|
|
|
ret = parse_nl_config(info, &xp);
|
|
if (ret)
|
|
return ret;
|
|
|
|
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
|
|
if (!msg)
|
|
return -ENOMEM;
|
|
|
|
rcu_read_lock();
|
|
|
|
ila = ila_lookup_by_params(&xp, ilan);
|
|
if (ila) {
|
|
ret = ila_dump_info(ila,
|
|
info->snd_portid,
|
|
info->snd_seq, 0, msg,
|
|
info->genlhdr->cmd);
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
|
|
if (ret < 0)
|
|
goto out_free;
|
|
|
|
return genlmsg_reply(msg, info);
|
|
|
|
out_free:
|
|
nlmsg_free(msg);
|
|
return ret;
|
|
}
|
|
|
|
struct ila_dump_iter {
|
|
struct rhashtable_iter rhiter;
|
|
int skip;
|
|
};
|
|
|
|
int ila_xlat_nl_dump_start(struct netlink_callback *cb)
|
|
{
|
|
struct net *net = sock_net(cb->skb->sk);
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
struct ila_dump_iter *iter;
|
|
|
|
iter = kmalloc(sizeof(*iter), GFP_KERNEL);
|
|
if (!iter)
|
|
return -ENOMEM;
|
|
|
|
rhashtable_walk_enter(&ilan->xlat.rhash_table, &iter->rhiter);
|
|
|
|
iter->skip = 0;
|
|
cb->args[0] = (long)iter;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int ila_xlat_nl_dump_done(struct netlink_callback *cb)
|
|
{
|
|
struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args[0];
|
|
|
|
rhashtable_walk_exit(&iter->rhiter);
|
|
|
|
kfree(iter);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int ila_xlat_nl_dump(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args[0];
|
|
struct rhashtable_iter *rhiter = &iter->rhiter;
|
|
int skip = iter->skip;
|
|
struct ila_map *ila;
|
|
int ret;
|
|
|
|
rhashtable_walk_start(rhiter);
|
|
|
|
/* Get first entry */
|
|
ila = rhashtable_walk_peek(rhiter);
|
|
|
|
if (ila && !IS_ERR(ila) && skip) {
|
|
/* Skip over visited entries */
|
|
|
|
while (ila && skip) {
|
|
/* Skip over any ila entries in this list that we
|
|
* have already dumped.
|
|
*/
|
|
ila = rcu_access_pointer(ila->next);
|
|
skip--;
|
|
}
|
|
}
|
|
|
|
skip = 0;
|
|
|
|
for (;;) {
|
|
if (IS_ERR(ila)) {
|
|
ret = PTR_ERR(ila);
|
|
if (ret == -EAGAIN) {
|
|
/* Table has changed and iter has reset. Return
|
|
* -EAGAIN to the application even if we have
|
|
* written data to the skb. The application
|
|
* needs to deal with this.
|
|
*/
|
|
|
|
goto out_ret;
|
|
} else {
|
|
break;
|
|
}
|
|
} else if (!ila) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
|
|
while (ila) {
|
|
ret = ila_dump_info(ila, NETLINK_CB(cb->skb).portid,
|
|
cb->nlh->nlmsg_seq, NLM_F_MULTI,
|
|
skb, ILA_CMD_GET);
|
|
if (ret)
|
|
goto out;
|
|
|
|
skip++;
|
|
ila = rcu_access_pointer(ila->next);
|
|
}
|
|
|
|
skip = 0;
|
|
ila = rhashtable_walk_next(rhiter);
|
|
}
|
|
|
|
out:
|
|
iter->skip = skip;
|
|
ret = (skb->len ? : ret);
|
|
|
|
out_ret:
|
|
rhashtable_walk_stop(rhiter);
|
|
return ret;
|
|
}
|
|
|
|
#define ILA_HASH_TABLE_SIZE 1024
|
|
|
|
int ila_xlat_init_net(struct net *net)
|
|
{
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
int err;
|
|
|
|
err = alloc_ila_locks(ilan);
|
|
if (err)
|
|
return err;
|
|
|
|
rhashtable_init(&ilan->xlat.rhash_table, &rht_params);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void ila_xlat_exit_net(struct net *net)
|
|
{
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
|
|
rhashtable_free_and_destroy(&ilan->xlat.rhash_table, ila_free_cb, NULL);
|
|
|
|
free_bucket_spinlocks(ilan->xlat.locks);
|
|
|
|
if (ilan->xlat.hooks_registered)
|
|
nf_unregister_net_hooks(net, ila_nf_hook_ops,
|
|
ARRAY_SIZE(ila_nf_hook_ops));
|
|
}
|
|
|
|
static int ila_xlat_addr(struct sk_buff *skb, bool sir2ila)
|
|
{
|
|
struct ila_map *ila;
|
|
struct ipv6hdr *ip6h = ipv6_hdr(skb);
|
|
struct net *net = dev_net(skb->dev);
|
|
struct ila_net *ilan = net_generic(net, ila_net_id);
|
|
struct ila_addr *iaddr = ila_a2i(&ip6h->daddr);
|
|
|
|
/* Assumes skb contains a valid IPv6 header that is pulled */
|
|
|
|
/* No check here that ILA type in the mapping matches what is in the
|
|
* address. We assume that whatever sender gaves us can be translated.
|
|
* The checksum mode however is relevant.
|
|
*/
|
|
|
|
rcu_read_lock();
|
|
|
|
ila = ila_lookup_wildcards(iaddr, skb->dev->ifindex, ilan);
|
|
if (ila)
|
|
ila_update_ipv6_locator(skb, &ila->xp.ip, sir2ila);
|
|
|
|
rcu_read_unlock();
|
|
|
|
return 0;
|
|
}
|