// SPDX-License-Identifier: GPL-2.0-only
/*
* xfrm_policy.c
*
* Changes:
* Mitsuru KANDA @USAGI
* Kazunori MIYAZAWA @USAGI
* Kunihiro Ishiguro <[email protected]>
* IPv6 support
* Kazunori MIYAZAWA @USAGI
* YOSHIFUJI Hideaki
* Split up af-specific portion
* Derek Atkins <[email protected]> Add the post_input processor
*
*/
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/notifier.h>
#include <linux/netdevice.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/cache.h>
#include <linux/cpu.h>
#include <linux/audit.h>
#include <linux/rhashtable.h>
#include <linux/if_tunnel.h>
#include <linux/icmp.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/inet_ecn.h>
#include <net/xfrm.h>
#include <net/ip.h>
#include <net/gre.h>
#if IS_ENABLED(CONFIG_IPV6_MIP6)
#include <net/mip6.h>
#endif
#ifdef CONFIG_XFRM_STATISTICS
#include <net/snmp.h>
#endif
#ifdef CONFIG_XFRM_ESPINTCP
#include <net/espintcp.h>
#endif
#include <net/inet_dscp.h>
#include "xfrm_hash.h"
#define XFRM_QUEUE_TMO_MIN ((unsigned)(HZ/10))
#define XFRM_QUEUE_TMO_MAX ((unsigned)(60*HZ))
#define XFRM_MAX_QUEUE_LEN 100
struct xfrm_flo {
struct dst_entry *dst_orig;
u8 flags;
};
/* prefixes smaller than this are stored in lists, not trees. */
#define INEXACT_PREFIXLEN_IPV4 16
#define INEXACT_PREFIXLEN_IPV6 48
struct xfrm_pol_inexact_node {
struct rb_node node;
union {
xfrm_address_t addr;
struct rcu_head rcu;
};
u8 prefixlen;
struct rb_root root;
/* the policies matching this node, can be empty list */
struct hlist_head hhead;
};
/* xfrm inexact policy search tree:
* xfrm_pol_inexact_bin = hash(dir,type,family,if_id);
* |
* +---- root_d: sorted by daddr:prefix
* | |
* | xfrm_pol_inexact_node
* | |
* | +- root: sorted by saddr/prefix
* | | |
* | | xfrm_pol_inexact_node
* | | |
* | | + root: unused
* | | |
* | | + hhead: saddr:daddr policies
* | |
* | +- coarse policies and all any:daddr policies
* |
* +---- root_s: sorted by saddr:prefix
* | |
* | xfrm_pol_inexact_node
* | |
* | + root: unused
* | |
* | + hhead: saddr:any policies
* |
* +---- coarse policies and all any:any policies
*
* Lookups return four candidate lists:
* 1. any:any list from top-level xfrm_pol_inexact_bin
* 2. any:daddr list from daddr tree
* 3. saddr:daddr list from 2nd level daddr tree
* 4. saddr:any list from saddr tree
*
* This result set then needs to be searched for the policy with
* the lowest priority. If two candidates have the same priority, the
* struct xfrm_policy pos member with the lower number is used.
*
* This replicates previous single-list-search algorithm which would
* return first matching policy in the (ordered-by-priority) list.
*/
struct xfrm_pol_inexact_key {
possible_net_t net;
u32 if_id;
u16 family;
u8 dir, type;
};
struct xfrm_pol_inexact_bin {
struct xfrm_pol_inexact_key k;
struct rhash_head head;
/* list containing '*:*' policies */
struct hlist_head hhead;
seqcount_spinlock_t count;
/* tree sorted by daddr/prefix */
struct rb_root root_d;
/* tree sorted by saddr/prefix */
struct rb_root root_s;
/* slow path below */
struct list_head inexact_bins;
struct rcu_head rcu;
};
enum xfrm_pol_inexact_candidate_type {
XFRM_POL_CAND_BOTH,
XFRM_POL_CAND_SADDR,
XFRM_POL_CAND_DADDR,
XFRM_POL_CAND_ANY,
XFRM_POL_CAND_MAX,
};
struct xfrm_pol_inexact_candidates {
struct hlist_head *res[XFRM_POL_CAND_MAX];
};
struct xfrm_flow_keys {
struct flow_dissector_key_basic basic;
struct flow_dissector_key_control control;
union {
struct flow_dissector_key_ipv4_addrs ipv4;
struct flow_dissector_key_ipv6_addrs ipv6;
} addrs;
struct flow_dissector_key_ip ip;
struct flow_dissector_key_icmp icmp;
struct flow_dissector_key_ports ports;
struct flow_dissector_key_keyid gre;
};
static struct flow_dissector xfrm_session_dissector __ro_after_init;
static DEFINE_SPINLOCK(xfrm_if_cb_lock);
static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly;
static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
__read_mostly;
static struct kmem_cache *xfrm_dst_cache __ro_after_init;
static struct rhashtable xfrm_policy_inexact_table;
static const struct rhashtable_params xfrm_pol_inexact_params;
static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr);
static int stale_bundle(struct dst_entry *dst);
static int xfrm_bundle_ok(struct xfrm_dst *xdst);
static void xfrm_policy_queue_process(struct timer_list *t);
static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
int dir);
static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir,
u32 if_id);
static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_lookup_rcu(struct net *net,
u8 type, u16 family, u8 dir, u32 if_id);
static struct xfrm_policy *
xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy,
bool excl);
static bool
xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
struct xfrm_pol_inexact_bin *b,
const xfrm_address_t *saddr,
const xfrm_address_t *daddr);
static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
{
return refcount_inc_not_zero(&policy->refcnt);
}
static inline bool
__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
{
const struct flowi4 *fl4 = &fl->u.ip4;
return addr4_match(fl4->daddr, sel->daddr.a4, sel->prefixlen_d) &&
addr4_match(fl4->saddr, sel->saddr.a4, sel->prefixlen_s) &&
!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
(fl4->flowi4_proto == sel->proto || !sel->proto) &&
(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
}
static inline bool
__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
{
const struct flowi6 *fl6 = &fl->u.ip6;
return addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
(fl6->flowi6_proto == sel->proto || !sel->proto) &&
(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
}
bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
unsigned short family)
{
switch (family) {
case AF_INET:
return __xfrm4_selector_match(sel, fl);
case AF_INET6:
return __xfrm6_selector_match(sel, fl);
}
return false;
}
static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
{
const struct xfrm_policy_afinfo *afinfo;
if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
return NULL;
rcu_read_lock();
afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
if (unlikely(!afinfo))
rcu_read_unlock();
return afinfo;
}
/* Called with rcu_read_lock(). */
static const struct xfrm_if_cb *xfrm_if_get_cb(void)
{
return rcu_dereference(xfrm_if_cb);
}
struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos, int oif,
const xfrm_address_t *saddr,
const xfrm_address_t *daddr,
int family, u32 mark)
{
const struct xfrm_policy_afinfo *afinfo;
struct dst_entry *dst;
afinfo = xfrm_policy_get_afinfo(family);
if (unlikely(afinfo == NULL))
return ERR_PTR(-EAFNOSUPPORT);
dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr, mark);
rcu_read_unlock();
return dst;
}
EXPORT_SYMBOL(__xfrm_dst_lookup);
static inline struct dst_entry *xfrm_dst_lookup(struct xfrm_state *x,
int tos, int oif,
xfrm_address_t *prev_saddr,
xfrm_address_t *prev_daddr,
int family, u32 mark)
{
struct net *net = xs_net(x);
xfrm_address_t *saddr = &x->props.saddr;
xfrm_address_t *daddr = &x->id.daddr;
struct dst_entry *dst;
if (x->type->flags & XFRM_TYPE_LOCAL_COADDR) {
saddr = x->coaddr;
daddr = prev_daddr;
}
if (x->type->flags & XFRM_TYPE_REMOTE_COADDR) {
saddr = prev_saddr;
daddr = x->coaddr;
}
dst = __xfrm_dst_lookup(net, tos, oif, saddr, daddr, family, mark);
if (!IS_ERR(dst)) {
if (prev_saddr != saddr)
memcpy(prev_saddr, saddr, sizeof(*prev_saddr));
if (prev_daddr != daddr)
memcpy(prev_daddr, daddr, sizeof(*prev_daddr));
}
return dst;
}
static inline unsigned long make_jiffies(long secs)
{
if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
return MAX_SCHEDULE_TIMEOUT-1;
else
return secs*HZ;
}
static void xfrm_policy_timer(struct timer_list *t)
{
struct xfrm_policy *xp = from_timer(xp, t, timer);
time64_t now = ktime_get_real_seconds();
time64_t next = TIME64_MAX;
int warn = 0;
int dir;
read_lock(&xp->lock);
if (unlikely(xp->walk.dead))
goto out;
dir = xfrm_policy_id2dir(xp->index);
if (xp->lft.hard_add_expires_seconds) {
time64_t tmo = xp->lft.hard_add_expires_seconds +
xp->curlft.add_time - now;
if (tmo <= 0)
goto expired;
if (tmo < next)
next = tmo;
}
if (xp->lft.hard_use_expires_seconds) {
time64_t tmo = xp->lft.hard_use_expires_seconds +
(READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
if (tmo <= 0)
goto expired;
if (tmo < next)
next = tmo;
}
if (xp->lft.soft_add_expires_seconds) {
time64_t tmo = xp->lft.soft_add_expires_seconds +
xp->curlft.add_time - now;
if (tmo <= 0) {
warn = 1;
tmo = XFRM_KM_TIMEOUT;
}
if (tmo < next)
next = tmo;
}
if (xp->lft.soft_use_expires_seconds) {
time64_t tmo = xp->lft.soft_use_expires_seconds +
(READ_ONCE(xp->curlft.use_time) ? : xp->curlft.add_time) - now;
if (tmo <= 0) {
warn = 1;
tmo = XFRM_KM_TIMEOUT;
}
if (tmo < next)
next = tmo;
}
if (warn)
km_policy_expired(xp, dir, 0, 0);
if (next != TIME64_MAX &&
!mod_timer(&xp->timer, jiffies + make_jiffies(next)))
xfrm_pol_hold(xp);
out:
read_unlock(&xp->lock);
xfrm_pol_put(xp);
return;
expired:
read_unlock(&xp->lock);
if (!xfrm_policy_delete(xp, dir))
km_policy_expired(xp, dir, 1, 0);
xfrm_pol_put(xp);
}
/* Allocate xfrm_policy. Not used here, it is supposed to be used by pfkeyv2
* SPD calls.
*/
struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
{
struct xfrm_policy *policy;
policy = kzalloc(sizeof(struct xfrm_policy), gfp);
if (policy) {
write_pnet(&policy->xp_net, net);
INIT_LIST_HEAD(&policy->walk.all);
INIT_HLIST_NODE(&policy->bydst);
INIT_HLIST_NODE(&policy->byidx);
rwlock_init(&policy->lock);
refcount_set(&policy->refcnt, 1);
skb_queue_head_init(&policy->polq.hold_queue);
timer_setup(&policy->timer, xfrm_policy_timer, 0);
timer_setup(&policy->polq.hold_timer,
xfrm_policy_queue_process, 0);
}
return policy;
}
EXPORT_SYMBOL(xfrm_policy_alloc);
static void xfrm_policy_destroy_rcu(struct rcu_head *head)
{
struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
security_xfrm_policy_free(policy->security);
kfree(policy);
}
/* Destroy xfrm_policy: descendant resources must be released to this moment. */
void xfrm_policy_destroy(struct xfrm_policy *policy)
{
BUG_ON(!policy->walk.dead);
if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
BUG();
xfrm_dev_policy_free(policy);
call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
}
EXPORT_SYMBOL(xfrm_policy_destroy);
/* Rule must be locked. Release descendant resources, announce
* entry dead. The rule must be unlinked from lists to the moment.
*/
static void xfrm_policy_kill(struct xfrm_policy *policy)
{
xfrm_dev_policy_delete(policy);
write_lock_bh(&policy->lock);
policy->walk.dead = 1;
write_unlock_bh(&policy->lock);
atomic_inc(&policy->genid);
if (del_timer(&policy->polq.hold_timer))
xfrm_pol_put(policy);
skb_queue_purge(&policy->polq.hold_queue);
if (del_timer(&policy->timer))
xfrm_pol_put(policy);
xfrm_pol_put(policy);
}
static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024;
static inline unsigned int idx_hash(struct net *net, u32 index)
{
return __idx_hash(index, net->xfrm.policy_idx_hmask);
}
/* calculate policy hash thresholds */
static void __get_hash_thresh(struct net *net,
unsigned short family, int dir,
u8 *dbits, u8 *sbits)
{
switch (family) {
case AF_INET:
*dbits = net->xfrm.policy_bydst[dir].dbits4;
*sbits = net->xfrm.policy_bydst[dir].sbits4;
break;
case AF_INET6:
*dbits = net->xfrm.policy_bydst[dir].dbits6;
*sbits = net->xfrm.policy_bydst[dir].sbits6;
break;
default:
*dbits = 0;
*sbits = 0;
}
}
static struct hlist_head *policy_hash_bysel(struct net *net,
const struct xfrm_selector *sel,
unsigned short family, int dir)
{
unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
unsigned int hash;
u8 dbits;
u8 sbits;
__get_hash_thresh(net, family, dir, &dbits, &sbits);
hash = __sel_hash(sel, family, hmask, dbits, sbits);
if (hash == hmask + 1)
return NULL;
return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
}
static struct hlist_head *policy_hash_direct(struct net *net,
const xfrm_address_t *daddr,
const xfrm_address_t *saddr,
unsigned short family, int dir)
{
unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
unsigned int hash;
u8 dbits;
u8 sbits;
__get_hash_thresh(net, family, dir, &dbits, &sbits);
hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
}
static void xfrm_dst_hash_transfer(struct net *net,
struct hlist_head *list,
struct hlist_head *ndsttable,
unsigned int nhashmask,
int dir)
{
struct hlist_node *tmp, *entry0 = NULL;
struct xfrm_policy *pol;
unsigned int h0 = 0;
u8 dbits;
u8 sbits;
redo:
hlist_for_each_entry_safe(pol, tmp, list, bydst) {
unsigned int h;
__get_hash_thresh(net, pol->family, dir, &dbits, &sbits);
h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
pol->family, nhashmask, dbits, sbits);
if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) {
hlist_del_rcu(&pol->bydst);
hlist_add_head_rcu(&pol->bydst, ndsttable + h);
h0 = h;
} else {
if (h != h0)
continue;
hlist_del_rcu(&pol->bydst);
hlist_add_behind_rcu(&pol->bydst, entry0);
}
entry0 = &pol->bydst;
}
if (!hlist_empty(list)) {
entry0 = NULL;
goto redo;
}
}
static void xfrm_idx_hash_transfer(struct hlist_head *list,
struct hlist_head *nidxtable,
unsigned int nhashmask)
{
struct hlist_node *tmp;
struct xfrm_policy *pol;
hlist_for_each_entry_safe(pol, tmp, list, byidx) {
unsigned int h;
h = __idx_hash(pol->index, nhashmask);
hlist_add_head(&pol->byidx, nidxtable+h);
}
}
static unsigned long xfrm_new_hash_mask(unsigned int old_hmask)
{
return ((old_hmask + 1) << 1) - 1;
}
static void xfrm_bydst_resize(struct net *net, int dir)
{
unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
unsigned int nhashmask = xfrm_new_hash_mask(hmask);
unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
struct hlist_head *ndst = xfrm_hash_alloc(nsize);
struct hlist_head *odst;
int i;
if (!ndst)
return;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
lockdep_is_held(&net->xfrm.xfrm_policy_lock));
for (i = hmask; i >= 0; i--)
xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
net->xfrm.policy_bydst[dir].hmask = nhashmask;
write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
synchronize_rcu();
xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
}
static void xfrm_byidx_resize(struct net *net)
{
unsigned int hmask = net->xfrm.policy_idx_hmask;
unsigned int nhashmask = xfrm_new_hash_mask(hmask);
unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
struct hlist_head *oidx = net->xfrm.policy_byidx;
struct hlist_head *nidx = xfrm_hash_alloc(nsize);
int i;
if (!nidx)
return;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
for (i = hmask; i >= 0; i--)
xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
net->xfrm.policy_byidx = nidx;
net->xfrm.policy_idx_hmask = nhashmask;
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
}
static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total)
{
unsigned int cnt = net->xfrm.policy_count[dir];
unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
if (total)
*total += cnt;
if ((hmask + 1) < xfrm_policy_hashmax &&
cnt > hmask)
return 1;
return 0;
}
static inline int xfrm_byidx_should_resize(struct net *net, int total)
{
unsigned int hmask = net->xfrm.policy_idx_hmask;
if ((hmask + 1) < xfrm_policy_hashmax &&
total > hmask)
return 1;
return 0;
}
void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
{
si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX];
si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX];
si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
si->spdhcnt = net->xfrm.policy_idx_hmask;
si->spdhmcnt = xfrm_policy_hashmax;
}
EXPORT_SYMBOL(xfrm_spd_getinfo);
static DEFINE_MUTEX(hash_resize_mutex);
static void xfrm_hash_resize(struct work_struct *work)
{
struct net *net = container_of(work, struct net, xfrm.policy_hash_work);
int dir, total;
mutex_lock(&hash_resize_mutex);
total = 0;
for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
if (xfrm_bydst_should_resize(net, dir, &total))
xfrm_bydst_resize(net, dir);
}
if (xfrm_byidx_should_resize(net, total))
xfrm_byidx_resize(net);
mutex_unlock(&hash_resize_mutex);
}
/* Make sure *pol can be inserted into fastbin.
* Useful to check that later insert requests will be successful
* (provided xfrm_policy_lock is held throughout).
*/
static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir)
{
struct xfrm_pol_inexact_bin *bin, *prev;
struct xfrm_pol_inexact_key k = {
.family = pol->family,
.type = pol->type,
.dir = dir,
.if_id = pol->if_id,
};
struct net *net = xp_net(pol);
lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
write_pnet(&k.net, net);
bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k,
xfrm_pol_inexact_params);
if (bin)
return bin;
bin = kzalloc(sizeof(*bin), GFP_ATOMIC);
if (!bin)
return NULL;
bin->k = k;
INIT_HLIST_HEAD(&bin->hhead);
bin->root_d = RB_ROOT;
bin->root_s = RB_ROOT;
seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock);
prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table,
&bin->k, &bin->head,
xfrm_pol_inexact_params);
if (!prev) {
list_add(&bin->inexact_bins, &net->xfrm.inexact_bins);
return bin;
}
kfree(bin);
return IS_ERR(prev) ? NULL : prev;
}
static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr,
int family, u8 prefixlen)
{
if (xfrm_addr_any(addr, family))
return true;
if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6)
return true;
if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4)
return true;
return false;
}
static bool
xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy)
{
const xfrm_address_t *addr;
bool saddr_any, daddr_any;
u8 prefixlen;
addr = &policy->selector.saddr;
prefixlen = policy->selector.prefixlen_s;
saddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
policy->family,
prefixlen);
addr = &policy->selector.daddr;
prefixlen = policy->selector.prefixlen_d;
daddr_any = xfrm_pol_inexact_addr_use_any_list(addr,
policy->family,
prefixlen);
return saddr_any && daddr_any;
}
static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node,
const xfrm_address_t *addr, u8 prefixlen)
{
node->addr = *addr;
node->prefixlen = prefixlen;
}
static struct xfrm_pol_inexact_node *
xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen)
{
struct xfrm_pol_inexact_node *node;
node = kzalloc(sizeof(*node), GFP_ATOMIC);
if (node)
xfrm_pol_inexact_node_init(node, addr, prefixlen);
return node;
}
static int xfrm_policy_addr_delta(const xfrm_address_t *a,
const xfrm_address_t *b,
u8 prefixlen, u16 family)
{
u32 ma, mb, mask;
unsigned int pdw, pbi;
int delta = 0;
switch (family) {
case AF_INET:
if (prefixlen == 0)
return 0;
mask = ~0U << (32 - prefixlen);
ma = ntohl(a->a4) & mask;
mb = ntohl(b->a4) & mask;
if (ma < mb)
delta = -1;
else if (ma > mb)
delta = 1;
break;
case AF_INET6:
pdw = prefixlen >> 5;
pbi = prefixlen & 0x1f;
if (pdw) {
delta = memcmp(a->a6, b->a6, pdw << 2);
if (delta)
return delta;
}
if (pbi) {
mask = ~0U << (32 - pbi);
ma = ntohl(a->a6[pdw]) & mask;
mb = ntohl(b->a6[pdw]) & mask;
if (ma < mb)
delta = -1;
else if (ma > mb)
delta = 1;
}
break;
default:
break;
}
return delta;
}
static void xfrm_policy_inexact_list_reinsert(struct net *net,
struct xfrm_pol_inexact_node *n,
u16 family)
{
unsigned int matched_s, matched_d;
struct xfrm_policy *policy, *p;
matched_s = 0;
matched_d = 0;
list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
struct hlist_node *newpos = NULL;
bool matches_s, matches_d;
if (policy->walk.dead || !policy->bydst_reinsert)
continue;
WARN_ON_ONCE(policy->family != family);
policy->bydst_reinsert = false;
hlist_for_each_entry(p, &n->hhead, bydst) {
if (policy->priority > p->priority)
newpos = &p->bydst;
else if (policy->priority == p->priority &&
policy->pos > p->pos)
newpos = &p->bydst;
else
break;
}
if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
hlist_add_behind_rcu(&policy->bydst, newpos);
else
hlist_add_head_rcu(&policy->bydst, &n->hhead);
/* paranoia checks follow.
* Check that the reinserted policy matches at least
* saddr or daddr for current node prefix.
*
* Matching both is fine, matching saddr in one policy
* (but not daddr) and then matching only daddr in another
* is a bug.
*/
matches_s = xfrm_policy_addr_delta(&policy->selector.saddr,
&n->addr,
n->prefixlen,
family) == 0;
matches_d = xfrm_policy_addr_delta(&policy->selector.daddr,
&n->addr,
n->prefixlen,
family) == 0;
if (matches_s && matches_d)
continue;
WARN_ON_ONCE(!matches_s && !matches_d);
if (matches_s)
matched_s++;
if (matches_d)
matched_d++;
WARN_ON_ONCE(matched_s && matched_d);
}
}
static void xfrm_policy_inexact_node_reinsert(struct net *net,
struct xfrm_pol_inexact_node *n,
struct rb_root *new,
u16 family)
{
struct xfrm_pol_inexact_node *node;
struct rb_node **p, *parent;
/* we should not have another subtree here */
WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root));
restart:
parent = NULL;
p = &new->rb_node;
while (*p) {
u8 prefixlen;
int delta;
parent = *p;
node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
prefixlen = min(node->prefixlen, n->prefixlen);
delta = xfrm_policy_addr_delta(&n->addr, &node->addr,
prefixlen, family);
if (delta < 0) {
p = &parent->rb_left;
} else if (delta > 0) {
p = &parent->rb_right;
} else {
bool same_prefixlen = node->prefixlen == n->prefixlen;
struct xfrm_policy *tmp;
hlist_for_each_entry(tmp, &n->hhead, bydst) {
tmp->bydst_reinsert = true;
hlist_del_rcu(&tmp->bydst);
}
node->prefixlen = prefixlen;
xfrm_policy_inexact_list_reinsert(net, node, family);
if (same_prefixlen) {
kfree_rcu(n, rcu);
return;
}
rb_erase(*p, new);
kfree_rcu(n, rcu);
n = node;
goto restart;
}
}
rb_link_node_rcu(&n->node, parent, p);
rb_insert_color(&n->node, new);
}
/* merge nodes v and n */
static void xfrm_policy_inexact_node_merge(struct net *net,
struct xfrm_pol_inexact_node *v,
struct xfrm_pol_inexact_node *n,
u16 family)
{
struct xfrm_pol_inexact_node *node;
struct xfrm_policy *tmp;
struct rb_node *rnode;
/* To-be-merged node v has a subtree.
*
* Dismantle it and insert its nodes to n->root.
*/
while ((rnode = rb_first(&v->root)) != NULL) {
node = rb_entry(rnode, struct xfrm_pol_inexact_node, node);
rb_erase(&node->node, &v->root);
xfrm_policy_inexact_node_reinsert(net, node, &n->root,
family);
}
hlist_for_each_entry(tmp, &v->hhead, bydst) {
tmp->bydst_reinsert = true;
hlist_del_rcu(&tmp->bydst);
}
xfrm_policy_inexact_list_reinsert(net, n, family);
}
static struct xfrm_pol_inexact_node *
xfrm_policy_inexact_insert_node(struct net *net,
struct rb_root *root,
xfrm_address_t *addr,
u16 family, u8 prefixlen, u8 dir)
{
struct xfrm_pol_inexact_node *cached = NULL;
struct rb_node **p, *parent = NULL;
struct xfrm_pol_inexact_node *node;
p = &root->rb_node;
while (*p) {
int delta;
parent = *p;
node = rb_entry(*p, struct xfrm_pol_inexact_node, node);
delta = xfrm_policy_addr_delta(addr, &node->addr,
node->prefixlen,
family);
if (delta == 0 && prefixlen >= node->prefixlen) {
WARN_ON_ONCE(cached); /* ipsec policies got lost */
return node;
}
if (delta < 0)
p = &parent->rb_left;
else
p = &parent->rb_right;
if (prefixlen < node->prefixlen) {
delta = xfrm_policy_addr_delta(addr, &node->addr,
prefixlen,
family);
if (delta)
continue;
/* This node is a subnet of the new prefix. It needs
* to be removed and re-inserted with the smaller
* prefix and all nodes that are now also covered
* by the reduced prefixlen.
*/
rb_erase(&node->node, root);
if (!cached) {
xfrm_pol_inexact_node_init(node, addr,
prefixlen);
cached = node;
} else {
/* This node also falls within the new
* prefixlen. Merge the to-be-reinserted
* node and this one.
*/
xfrm_policy_inexact_node_merge(net, node,
cached, family);
kfree_rcu(node, rcu);
}
/* restart */
p = &root->rb_node;
parent = NULL;
}
}
node = cached;
if (!node) {
node = xfrm_pol_inexact_node_alloc(addr, prefixlen);
if (!node)
return NULL;
}
rb_link_node_rcu(&node->node, parent, p);
rb_insert_color(&node->node, root);
return node;
}
static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm)
{
struct xfrm_pol_inexact_node *node;
struct rb_node *rn = rb_first(r);
while (rn) {
node = rb_entry(rn, struct xfrm_pol_inexact_node, node);
xfrm_policy_inexact_gc_tree(&node->root, rm);
rn = rb_next(rn);
if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) {
WARN_ON_ONCE(rm);
continue;
}
rb_erase(&node->node, r);
kfree_rcu(node, rcu);
}
}
static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit)
{
write_seqcount_begin(&b->count);
xfrm_policy_inexact_gc_tree(&b->root_d, net_exit);
xfrm_policy_inexact_gc_tree(&b->root_s, net_exit);
write_seqcount_end(&b->count);
if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) ||
!hlist_empty(&b->hhead)) {
WARN_ON_ONCE(net_exit);
return;
}
if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head,
xfrm_pol_inexact_params) == 0) {
list_del(&b->inexact_bins);
kfree_rcu(b, rcu);
}
}
static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b)
{
struct net *net = read_pnet(&b->k.net);
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
__xfrm_policy_inexact_prune_bin(b, false);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
}
static void __xfrm_policy_inexact_flush(struct net *net)
{
struct xfrm_pol_inexact_bin *bin, *t;
lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins)
__xfrm_policy_inexact_prune_bin(bin, false);
}
static struct hlist_head *
xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin,
struct xfrm_policy *policy, u8 dir)
{
struct xfrm_pol_inexact_node *n;
struct net *net;
net = xp_net(policy);
lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
if (xfrm_policy_inexact_insert_use_any_list(policy))
return &bin->hhead;
if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr,
policy->family,
policy->selector.prefixlen_d)) {
write_seqcount_begin(&bin->count);
n = xfrm_policy_inexact_insert_node(net,
&bin->root_s,
&policy->selector.saddr,
policy->family,
policy->selector.prefixlen_s,
dir);
write_seqcount_end(&bin->count);
if (!n)
return NULL;
return &n->hhead;
}
/* daddr is fixed */
write_seqcount_begin(&bin->count);
n = xfrm_policy_inexact_insert_node(net,
&bin->root_d,
&policy->selector.daddr,
policy->family,
policy->selector.prefixlen_d, dir);
write_seqcount_end(&bin->count);
if (!n)
return NULL;
/* saddr is wildcard */
if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr,
policy->family,
policy->selector.prefixlen_s))
return &n->hhead;
write_seqcount_begin(&bin->count);
n = xfrm_policy_inexact_insert_node(net,
&n->root,
&policy->selector.saddr,
policy->family,
policy->selector.prefixlen_s, dir);
write_seqcount_end(&bin->count);
if (!n)
return NULL;
return &n->hhead;
}
static struct xfrm_policy *
xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl)
{
struct xfrm_pol_inexact_bin *bin;
struct xfrm_policy *delpol;
struct hlist_head *chain;
struct net *net;
bin = xfrm_policy_inexact_alloc_bin(policy, dir);
if (!bin)
return ERR_PTR(-ENOMEM);
net = xp_net(policy);
lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir);
if (!chain) {
__xfrm_policy_inexact_prune_bin(bin, false);
return ERR_PTR(-ENOMEM);
}
delpol = xfrm_policy_insert_list(chain, policy, excl);
if (delpol && excl) {
__xfrm_policy_inexact_prune_bin(bin, false);
return ERR_PTR(-EEXIST);
}
if (delpol)
__xfrm_policy_inexact_prune_bin(bin, false);
return delpol;
}
static bool xfrm_policy_is_dead_or_sk(const struct xfrm_policy *policy)
{
int dir;
if (policy->walk.dead)
return true;
dir = xfrm_policy_id2dir(policy->index);
return dir >= XFRM_POLICY_MAX;
}
static void xfrm_hash_rebuild(struct work_struct *work)
{
struct net *net = container_of(work, struct net,
xfrm.policy_hthresh.work);
struct xfrm_policy *pol;
struct xfrm_policy *policy;
struct hlist_head *chain;
struct hlist_node *newpos;
int dir;
unsigned seq;
u8 lbits4, rbits4, lbits6, rbits6;
mutex_lock(&hash_resize_mutex);
/* read selector prefixlen thresholds */
do {
seq = read_seqbegin(&net->xfrm.policy_hthresh.lock);
lbits4 = net->xfrm.policy_hthresh.lbits4;
rbits4 = net->xfrm.policy_hthresh.rbits4;
lbits6 = net->xfrm.policy_hthresh.lbits6;
rbits6 = net->xfrm.policy_hthresh.rbits6;
} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
/* make sure that we can insert the indirect policies again before
* we start with destructive action.
*/
list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
struct xfrm_pol_inexact_bin *bin;
u8 dbits, sbits;
if (xfrm_policy_is_dead_or_sk(policy))
continue;
dir = xfrm_policy_id2dir(policy->index);
if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
if (policy->family == AF_INET) {
dbits = rbits4;
sbits = lbits4;
} else {
dbits = rbits6;
sbits = lbits6;
}
} else {
if (policy->family == AF_INET) {
dbits = lbits4;
sbits = rbits4;
} else {
dbits = lbits6;
sbits = rbits6;
}
}
if (policy->selector.prefixlen_d < dbits ||
policy->selector.prefixlen_s < sbits)
continue;
bin = xfrm_policy_inexact_alloc_bin(policy, dir);
if (!bin)
goto out_unlock;
if (!xfrm_policy_inexact_alloc_chain(bin, policy, dir))
goto out_unlock;
}
for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
if ((dir & XFRM_POLICY_MASK) == XFRM_POLICY_OUT) {
/* dir out => dst = remote, src = local */
net->xfrm.policy_bydst[dir].dbits4 = rbits4;
net->xfrm.policy_bydst[dir].sbits4 = lbits4;
net->xfrm.policy_bydst[dir].dbits6 = rbits6;
net->xfrm.policy_bydst[dir].sbits6 = lbits6;
} else {
/* dir in/fwd => dst = local, src = remote */
net->xfrm.policy_bydst[dir].dbits4 = lbits4;
net->xfrm.policy_bydst[dir].sbits4 = rbits4;
net->xfrm.policy_bydst[dir].dbits6 = lbits6;
net->xfrm.policy_bydst[dir].sbits6 = rbits6;
}
}
/* re-insert all policies by order of creation */
list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
if (xfrm_policy_is_dead_or_sk(policy))
continue;
hlist_del_rcu(&policy->bydst);
newpos = NULL;
dir = xfrm_policy_id2dir(policy->index);
chain = policy_hash_bysel(net, &policy->selector,
policy->family, dir);
if (!chain) {
void *p = xfrm_policy_inexact_insert(policy, dir, 0);
WARN_ONCE(IS_ERR(p), "reinsert: %ld\n", PTR_ERR(p));
continue;
}
hlist_for_each_entry(pol, chain, bydst) {
if (policy->priority >= pol->priority)
newpos = &pol->bydst;
else
break;
}
if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
hlist_add_behind_rcu(&policy->bydst, newpos);
else
hlist_add_head_rcu(&policy->bydst, chain);
}
out_unlock:
__xfrm_policy_inexact_flush(net);
write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
mutex_unlock(&hash_resize_mutex);
}
void xfrm_policy_hash_rebuild(struct net *net)
{
schedule_work(&net->xfrm.policy_hthresh.work);
}
EXPORT_SYMBOL(xfrm_policy_hash_rebuild);
/* Generate new index... KAME seems to generate them ordered by cost
* of an absolute inpredictability of ordering of rules. This will not pass. */
static u32 xfrm_gen_index(struct net *net, int dir, u32 index)
{
for (;;) {
struct hlist_head *list;
struct xfrm_policy *p;
u32 idx;
int found;
if (!index) {
idx = (net->xfrm.idx_generator | dir);
net->xfrm.idx_generator += 8;
} else {
idx = index;
index = 0;
}
if (idx == 0)
idx = 8;
list = net->xfrm.policy_byidx + idx_hash(net, idx);
found = 0;
hlist_for_each_entry(p, list, byidx) {
if (p->index == idx) {
found = 1;
break;
}
}
if (!found)
return idx;
}
}
static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2)
{
u32 *p1 = (u32 *) s1;
u32 *p2 = (u32 *) s2;
int len = sizeof(struct xfrm_selector) / sizeof(u32);
int i;
for (i = 0; i < len; i++) {
if (p1[i] != p2[i])
return 1;
}
return 0;
}
static void xfrm_policy_requeue(struct xfrm_policy *old,
struct xfrm_policy *new)
{
struct xfrm_policy_queue *pq = &old->polq;
struct sk_buff_head list;
if (skb_queue_empty(&pq->hold_queue))
return;
__skb_queue_head_init(&list);
spin_lock_bh(&pq->hold_queue.lock);
skb_queue_splice_init(&pq->hold_queue, &list);
if (del_timer(&pq->hold_timer))
xfrm_pol_put(old);
spin_unlock_bh(&pq->hold_queue.lock);
pq = &new->polq;
spin_lock_bh(&pq->hold_queue.lock);
skb_queue_splice(&list, &pq->hold_queue);
pq->timeout = XFRM_QUEUE_TMO_MIN;
if (!mod_timer(&pq->hold_timer, jiffies))
xfrm_pol_hold(new);
spin_unlock_bh(&pq->hold_queue.lock);
}
static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark,
struct xfrm_policy *pol)
{
return mark->v == pol->mark.v && mark->m == pol->mark.m;
}
static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed)
{
const struct xfrm_pol_inexact_key *k = data;
u32 a = k->type << 24 | k->dir << 16 | k->family;
return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)),
seed);
}
static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed)
{
const struct xfrm_pol_inexact_bin *b = data;
return xfrm_pol_bin_key(&b->k, 0, seed);
}
static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg,
const void *ptr)
{
const struct xfrm_pol_inexact_key *key = arg->key;
const struct xfrm_pol_inexact_bin *b = ptr;
int ret;
if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net)))
return -1;
ret = b->k.dir ^ key->dir;
if (ret)
return ret;
ret = b->k.type ^ key->type;
if (ret)
return ret;
ret = b->k.family ^ key->family;
if (ret)
return ret;
return b->k.if_id ^ key->if_id;
}
static const struct rhashtable_params xfrm_pol_inexact_params = {
.head_offset = offsetof(struct xfrm_pol_inexact_bin, head),
.hashfn = xfrm_pol_bin_key,
.obj_hashfn = xfrm_pol_bin_obj,
.obj_cmpfn = xfrm_pol_bin_cmp,
.automatic_shrinking = true,
};
static struct xfrm_policy *xfrm_policy_insert_list(struct hlist_head *chain,
struct xfrm_policy *policy,
bool excl)
{
struct xfrm_policy *pol, *newpos = NULL, *delpol = NULL;
hlist_for_each_entry(pol, chain, bydst) {
if (pol->type == policy->type &&
pol->if_id == policy->if_id &&
!selector_cmp(&pol->selector, &policy->selector) &&
xfrm_policy_mark_match(&policy->mark, pol) &&
xfrm_sec_ctx_match(pol->security, policy->security) &&
!WARN_ON(delpol)) {
if (excl)
return ERR_PTR(-EEXIST);
delpol = pol;
if (policy->priority > pol->priority)
continue;
} else if (policy->priority >= pol->priority) {
newpos = pol;
continue;
}
if (delpol)
break;
}
if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET)
hlist_add_behind_rcu(&policy->bydst, &newpos->bydst);
else
/* Packet offload policies enter to the head
* to speed-up lookups.
*/
hlist_add_head_rcu(&policy->bydst, chain);
return delpol;
}
int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
{
struct net *net = xp_net(policy);
struct xfrm_policy *delpol;
struct hlist_head *chain;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
if (chain)
delpol = xfrm_policy_insert_list(chain, policy, excl);
else
delpol = xfrm_policy_inexact_insert(policy, dir, excl);
if (IS_ERR(delpol)) {
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return PTR_ERR(delpol);
}
__xfrm_policy_link(policy, dir);
/* After previous checking, family can either be AF_INET or AF_INET6 */
if (policy->family == AF_INET)
rt_genid_bump_ipv4(net);
else
rt_genid_bump_ipv6(net);
if (delpol) {
xfrm_policy_requeue(delpol, policy);
__xfrm_policy_unlink(delpol, dir);
}
policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index);
hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index));
policy->curlft.add_time = ktime_get_real_seconds();
policy->curlft.use_time = 0;
if (!mod_timer(&policy->timer, jiffies + HZ))
xfrm_pol_hold(policy);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (delpol)
xfrm_policy_kill(delpol);
else if (xfrm_bydst_should_resize(net, dir, NULL))
schedule_work(&net->xfrm.policy_hash_work);
return 0;
}
EXPORT_SYMBOL(xfrm_policy_insert);
static struct xfrm_policy *
__xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark,
u32 if_id, u8 type, int dir, struct xfrm_selector *sel,
struct xfrm_sec_ctx *ctx)
{
struct xfrm_policy *pol;
if (!chain)
return NULL;
hlist_for_each_entry(pol, chain, bydst) {
if (pol->type == type &&
pol->if_id == if_id &&
xfrm_policy_mark_match(mark, pol) &&
!selector_cmp(sel, &pol->selector) &&
xfrm_sec_ctx_match(ctx, pol->security))
return pol;
}
return NULL;
}
struct xfrm_policy *
xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id,
u8 type, int dir, struct xfrm_selector *sel,
struct xfrm_sec_ctx *ctx, int delete, int *err)
{
struct xfrm_pol_inexact_bin *bin = NULL;
struct xfrm_policy *pol, *ret = NULL;
struct hlist_head *chain;
*err = 0;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = policy_hash_bysel(net, sel, sel->family, dir);
if (!chain) {
struct xfrm_pol_inexact_candidates cand;
int i;
bin = xfrm_policy_inexact_lookup(net, type,
sel->family, dir, if_id);
if (!bin) {
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return NULL;
}
if (!xfrm_policy_find_inexact_candidates(&cand, bin,
&sel->saddr,
&sel->daddr)) {
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return NULL;
}
pol = NULL;
for (i = 0; i < ARRAY_SIZE(cand.res); i++) {
struct xfrm_policy *tmp;
tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark,
if_id, type, dir,
sel, ctx);
if (!tmp)
continue;
if (!pol || tmp->pos < pol->pos)
pol = tmp;
}
} else {
pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir,
sel, ctx);
}
if (pol) {
xfrm_pol_hold(pol);
if (delete) {
*err = security_xfrm_policy_delete(pol->security);
if (*err) {
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return pol;
}
__xfrm_policy_unlink(pol, dir);
}
ret = pol;
}
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (ret && delete)
xfrm_policy_kill(ret);
if (bin && delete)
xfrm_policy_inexact_prune_bin(bin);
return ret;
}
EXPORT_SYMBOL(xfrm_policy_bysel_ctx);
struct xfrm_policy *
xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id,
u8 type, int dir, u32 id, int delete, int *err)
{
struct xfrm_policy *pol, *ret;
struct hlist_head *chain;
*err = -ENOENT;
if (xfrm_policy_id2dir(id) != dir)
return NULL;
*err = 0;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = net->xfrm.policy_byidx + idx_hash(net, id);
ret = NULL;
hlist_for_each_entry(pol, chain, byidx) {
if (pol->type == type && pol->index == id &&
pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) {
xfrm_pol_hold(pol);
if (delete) {
*err = security_xfrm_policy_delete(
pol->security);
if (*err) {
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return pol;
}
__xfrm_policy_unlink(pol, dir);
}
ret = pol;
break;
}
}
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (ret && delete)
xfrm_policy_kill(ret);
return ret;
}
EXPORT_SYMBOL(xfrm_policy_byid);
#ifdef CONFIG_SECURITY_NETWORK_XFRM
static inline int
xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
{
struct xfrm_policy *pol;
int err = 0;
list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
if (pol->walk.dead ||
xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
pol->type != type)
continue;
err = security_xfrm_policy_delete(pol->security);
if (err) {
xfrm_audit_policy_delete(pol, 0, task_valid);
return err;
}
}
return err;
}
static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
struct net_device *dev,
bool task_valid)
{
struct xfrm_policy *pol;
int err = 0;
list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
if (pol->walk.dead ||
xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX ||
pol->xdo.dev != dev)
continue;
err = security_xfrm_policy_delete(pol->security);
if (err) {
xfrm_audit_policy_delete(pol, 0, task_valid);
return err;
}
}
return err;
}
#else
static inline int
xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid)
{
return 0;
}
static inline int xfrm_dev_policy_flush_secctx_check(struct net *net,
struct net_device *dev,
bool task_valid)
{
return 0;
}
#endif
int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
{
int dir, err = 0, cnt = 0;
struct xfrm_policy *pol;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
err = xfrm_policy_flush_secctx_check(net, type, task_valid);
if (err)
goto out;
again:
list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
if (pol->walk.dead)
continue;
dir = xfrm_policy_id2dir(pol->index);
if (dir >= XFRM_POLICY_MAX ||
pol->type != type)
continue;
__xfrm_policy_unlink(pol, dir);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
cnt++;
xfrm_audit_policy_delete(pol, 1, task_valid);
xfrm_policy_kill(pol);
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
goto again;
}
if (cnt)
__xfrm_policy_inexact_flush(net);
else
err = -ESRCH;
out:
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return err;
}
EXPORT_SYMBOL(xfrm_policy_flush);
int xfrm_dev_policy_flush(struct net *net, struct net_device *dev,
bool task_valid)
{
int dir, err = 0, cnt = 0;
struct xfrm_policy *pol;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid);
if (err)
goto out;
again:
list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) {
if (pol->walk.dead)
continue;
dir = xfrm_policy_id2dir(pol->index);
if (dir >= XFRM_POLICY_MAX ||
pol->xdo.dev != dev)
continue;
__xfrm_policy_unlink(pol, dir);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
cnt++;
xfrm_audit_policy_delete(pol, 1, task_valid);
xfrm_policy_kill(pol);
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
goto again;
}
if (cnt)
__xfrm_policy_inexact_flush(net);
else
err = -ESRCH;
out:
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return err;
}
EXPORT_SYMBOL(xfrm_dev_policy_flush);
int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
int (*func)(struct xfrm_policy *, int, int, void*),
void *data)
{
struct xfrm_policy *pol;
struct xfrm_policy_walk_entry *x;
int error = 0;
if (walk->type >= XFRM_POLICY_TYPE_MAX &&
walk->type != XFRM_POLICY_TYPE_ANY)
return -EINVAL;
if (list_empty(&walk->walk.all) && walk->seq != 0)
return 0;
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
if (list_empty(&walk->walk.all))
x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
else
x = list_first_entry(&walk->walk.all,
struct xfrm_policy_walk_entry, all);
list_for_each_entry_from(x, &net->xfrm.policy_all, all) {
if (x->dead)
continue;
pol = container_of(x, struct xfrm_policy, walk);
if (walk->type != XFRM_POLICY_TYPE_ANY &&
walk->type != pol->type)
continue;
error = func(pol, xfrm_policy_id2dir(pol->index),
walk->seq, data);
if (error) {
list_move_tail(&walk->walk.all, &x->all);
goto out;
}
walk->seq++;
}
if (walk->seq == 0) {
error = -ENOENT;
goto out;
}
list_del_init(&walk->walk.all);
out:
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return error;
}
EXPORT_SYMBOL(xfrm_policy_walk);
void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type)
{
INIT_LIST_HEAD(&walk->walk.all);
walk->walk.dead = 1;
walk->type = type;
walk->seq = 0;
}
EXPORT_SYMBOL(xfrm_policy_walk_init);
void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
{
if (list_empty(&walk->walk.all))
return;
spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
list_del(&walk->walk.all);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
}
EXPORT_SYMBOL(xfrm_policy_walk_done);
/*
* Find policy to apply to this flow.
*
* Returns 0 if policy found, else an -errno.
*/
static int xfrm_policy_match(const struct xfrm_policy *pol,
const struct flowi *fl,
u8 type, u16 family, u32 if_id)
{
const struct xfrm_selector *sel = &pol->selector;
int ret = -ESRCH;
bool match;
if (pol->family != family ||
pol->if_id != if_id ||
(fl->flowi_mark & pol->mark.m) != pol->mark.v ||
pol->type != type)
return ret;
match = xfrm_selector_match(sel, fl, family);
if (match)
ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid);
return ret;
}
static struct xfrm_pol_inexact_node *
xfrm_policy_lookup_inexact_addr(const struct rb_root *r,
seqcount_spinlock_t *count,
const xfrm_address_t *addr, u16 family)
{
const struct rb_node *parent;
int seq;
again:
seq = read_seqcount_begin(count);
parent = rcu_dereference_raw(r->rb_node);
while (parent) {
struct xfrm_pol_inexact_node *node;
int delta;
node = rb_entry(parent, struct xfrm_pol_inexact_node, node);
delta = xfrm_policy_addr_delta(addr, &node->addr,
node->prefixlen, family);
if (delta < 0) {
parent = rcu_dereference_raw(parent->rb_left);
continue;
} else if (delta > 0) {
parent = rcu_dereference_raw(parent->rb_right);
continue;
}
return node;
}
if (read_seqcount_retry(count, seq))
goto again;
return NULL;
}
static bool
xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand,
struct xfrm_pol_inexact_bin *b,
const xfrm_address_t *saddr,
const xfrm_address_t *daddr)
{
struct xfrm_pol_inexact_node *n;
u16 family;
if (!b)
return false;
family = b->k.family;
memset(cand, 0, sizeof(*cand));
cand->res[XFRM_POL_CAND_ANY] = &b->hhead;
n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr,
family);
if (n) {
cand->res[XFRM_POL_CAND_DADDR] = &n->hhead;
n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr,
family);
if (n)
cand->res[XFRM_POL_CAND_BOTH] = &n->hhead;
}
n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr,
family);
if (n)
cand->res[XFRM_POL_CAND_SADDR] = &n->hhead;
return true;
}
static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family,
u8 dir, u32 if_id)
{
struct xfrm_pol_inexact_key k = {
.family = family,
.type = type,
.dir = dir,
.if_id = if_id,
};
write_pnet(&k.net, net);
return rhashtable_lookup(&xfrm_policy_inexact_table, &k,
xfrm_pol_inexact_params);
}
static struct xfrm_pol_inexact_bin *
xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family,
u8 dir, u32 if_id)
{
struct xfrm_pol_inexact_bin *bin;
lockdep_assert_held(&net->xfrm.xfrm_policy_lock);
rcu_read_lock();
bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
rcu_read_unlock();
return bin;
}
static struct xfrm_policy *
__xfrm_policy_eval_candidates(struct hlist_head *chain,
struct xfrm_policy *prefer,
const struct flowi *fl,
u8 type, u16 family, u32 if_id)
{
u32 priority = prefer ? prefer->priority : ~0u;
struct xfrm_policy *pol;
if (!chain)
return NULL;
hlist_for_each_entry_rcu(pol, chain, bydst) {
int err;
if (pol->priority > priority)
break;
err = xfrm_policy_match(pol, fl, type, family, if_id);
if (err) {
if (err != -ESRCH)
return ERR_PTR(err);
continue;
}
if (prefer) {
/* matches. Is it older than *prefer? */
if (pol->priority == priority &&
prefer->pos < pol->pos)
return prefer;
}
return pol;
}
return NULL;
}
static struct xfrm_policy *
xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand,
struct xfrm_policy *prefer,
const struct flowi *fl,
u8 type, u16 family, u32 if_id)
{
struct xfrm_policy *tmp;
int i;
for (i = 0; i < ARRAY_SIZE(cand->res); i++) {
tmp = __xfrm_policy_eval_candidates(cand->res[i],
prefer,
fl, type, family, if_id);
if (!tmp)
continue;
if (IS_ERR(tmp))
return tmp;
prefer = tmp;
}
return prefer;
}
static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
const struct flowi *fl,
u16 family, u8 dir,
u32 if_id)
{
struct xfrm_pol_inexact_candidates cand;
const xfrm_address_t *daddr, *saddr;
struct xfrm_pol_inexact_bin *bin;
struct xfrm_policy *pol, *ret;
struct hlist_head *chain;
unsigned int sequence;
int err;
daddr = xfrm_flowi_daddr(fl, family);
saddr = xfrm_flowi_saddr(fl, family);
if (unlikely(!daddr || !saddr))
return NULL;
rcu_read_lock();
retry:
do {
sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation);
chain = policy_hash_direct(net, daddr, saddr, family, dir);
} while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence));
ret = NULL;
hlist_for_each_entry_rcu(pol, chain, bydst) {
err = xfrm_policy_match(pol, fl, type, family, if_id);
if (err) {
if (err == -ESRCH)
continue;
else {
ret = ERR_PTR(err);
goto fail;
}
} else {
ret = pol;
break;
}
}
if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET)
goto skip_inexact;
bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id);
if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr,
daddr))
goto skip_inexact;
pol = xfrm_policy_eval_candidates(&cand, ret, fl, type,
family, if_id);
if (pol) {
ret = pol;
if (IS_ERR(pol))
goto fail;
}
skip_inexact:
if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence))
goto retry;
if (ret && !xfrm_pol_hold_rcu(ret))
goto retry;
fail:
rcu_read_unlock();
return ret;
}
static struct xfrm_policy *xfrm_policy_lookup(struct net *net,
const struct flowi *fl,
u16 family, u8 dir, u32 if_id)
{
#ifdef CONFIG_XFRM_SUB_POLICY
struct xfrm_policy *pol;
pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family,
dir, if_id);
if (pol != NULL)
return pol;
#endif
return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family,
dir, if_id);
}
static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
const struct flowi *fl,
u16 family, u32 if_id)
{
struct xfrm_policy *pol;
rcu_read_lock();
again:
pol = rcu_dereference(sk->sk_policy[dir]);
if (pol != NULL) {
bool match;
int err = 0;
if (pol->family != family) {
pol = NULL;
goto out;
}
match = xfrm_selector_match(&pol->selector, fl, family);
if (match) {
if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v ||
pol->if_id != if_id) {
pol = NULL;
goto out;
}
err = security_xfrm_policy_lookup(pol->security,
fl->flowi_secid);
if (!err) {
if (!xfrm_pol_hold_rcu(pol))
goto again;
} else if (err == -ESRCH) {
pol = NULL;
} else {
pol = ERR_PTR(err);
}
} else
pol = NULL;
}
out:
rcu_read_unlock();
return pol;
}
static u32 xfrm_gen_pos_slow(struct net *net)
{
struct xfrm_policy *policy;
u32 i = 0;
/* oldest entry is last in list */
list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) {
if (!xfrm_policy_is_dead_or_sk(policy))
policy->pos = ++i;
}
return i;
}
static u32 xfrm_gen_pos(struct net *net)
{
const struct xfrm_policy *policy;
u32 i = 0;
/* most recently added policy is at the head of the list */
list_for_each_entry(policy, &net->xfrm.policy_all, walk.all) {
if (xfrm_policy_is_dead_or_sk(policy))
continue;
if (policy->pos == UINT_MAX)
return xfrm_gen_pos_slow(net);
i = policy->pos + 1;
break;
}
return i;
}
static void __xfrm_policy_link(struct xfrm_policy *pol, int dir)
{
struct net *net = xp_net(pol);
switch (dir) {
case XFRM_POLICY_IN:
case XFRM_POLICY_FWD:
case XFRM_POLICY_OUT:
pol->pos = xfrm_gen_pos(net);
break;
}
list_add(&pol->walk.all, &net->xfrm.policy_all);
net->xfrm.policy_count[dir]++;
xfrm_pol_hold(pol);
}
static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
int dir)
{
struct net *net = xp_net(pol);
if (list_empty(&pol->walk.all))
return NULL;
/* Socket policies are not hashed. */
if (!hlist_unhashed(&pol->bydst)) {
hlist_del_rcu(&pol->bydst);
hlist_del(&pol->byidx);
}
list_del_init(&pol->walk.all);
net->xfrm.policy_count[dir]--;
return pol;
}
static void xfrm_sk_policy_link(struct xfrm_policy *pol, int dir)
{
__xfrm_policy_link(pol, XFRM_POLICY_MAX + dir);
}
static void xfrm_sk_policy_unlink(struct xfrm_policy *pol, int dir)
{
__xfrm_policy_unlink(pol, XFRM_POLICY_MAX + dir);
}
int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
{
struct net *net = xp_net(pol);
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
pol = __xfrm_policy_unlink(pol, dir);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (pol) {
xfrm_policy_kill(pol);
return 0;
}
return -ENOENT;
}
EXPORT_SYMBOL(xfrm_policy_delete);
int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
{
struct net *net = sock_net(sk);
struct xfrm_policy *old_pol;
#ifdef CONFIG_XFRM_SUB_POLICY
if (pol && pol->type != XFRM_POLICY_TYPE_MAIN)
return -EINVAL;
#endif
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
old_pol = rcu_dereference_protected(sk->sk_policy[dir],
lockdep_is_held(&net->xfrm.xfrm_policy_lock));
if (pol) {
pol->curlft.add_time = ktime_get_real_seconds();
pol->index = xfrm_gen_index(net, XFRM_POLICY_MAX+dir, 0);
xfrm_sk_policy_link(pol, dir);
}
rcu_assign_pointer(sk->sk_policy[dir], pol);
if (old_pol) {
if (pol)
xfrm_policy_requeue(old_pol, pol);
/* Unlinking succeeds always. This is the only function
* allowed to delete or replace socket policy.
*/
xfrm_sk_policy_unlink(old_pol, dir);
}
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (old_pol) {
xfrm_policy_kill(old_pol);
}
return 0;
}
static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
{
struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
struct net *net = xp_net(old);
if (newp) {
newp->selector = old->selector;
if (security_xfrm_policy_clone(old->security,
&newp->security)) {
kfree(newp);
return NULL; /* ENOMEM */
}
newp->lft = old->lft;
newp->curlft = old->curlft;
newp->mark = old->mark;
newp->if_id = old->if_id;
newp->action = old->action;
newp->flags = old->flags;
newp->xfrm_nr = old->xfrm_nr;
newp->index = old->index;
newp->type = old->type;
newp->family = old->family;
memcpy(newp->xfrm_vec, old->xfrm_vec,
newp->xfrm_nr*sizeof(struct xfrm_tmpl));
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
xfrm_sk_policy_link(newp, dir);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
xfrm_pol_put(newp);
}
return newp;
}
int __xfrm_sk_clone_policy(struct sock *sk, const struct sock *osk)
{
const struct xfrm_policy *p;
struct xfrm_policy *np;
int i, ret = 0;
rcu_read_lock();
for (i = 0; i < 2; i++) {
p = rcu_dereference(osk->sk_policy[i]);
if (p) {
np = clone_policy(p, i);
if (unlikely(!np)) {
ret = -ENOMEM;
break;
}
rcu_assign_pointer(sk->sk_policy[i], np);
}
}
rcu_read_unlock();
return ret;
}
static int
xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
xfrm_address_t *remote, unsigned short family, u32 mark)
{
int err;
const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
if (unlikely(afinfo == NULL))
return -EINVAL;
err = afinfo->get_saddr(net, oif, local, remote, mark);
rcu_read_unlock();
return err;
}
/* Resolve list of templates for the flow, given policy. */
static int
xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
struct xfrm_state **xfrm, unsigned short family)
{
struct net *net = xp_net(policy);
int nx;
int i, error;
xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family);
xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family);
xfrm_address_t tmp;
for (nx = 0, i = 0; i < policy->xfrm_nr; i++) {
struct xfrm_state *x;
xfrm_address_t *remote = daddr;
xfrm_address_t *local = saddr;
struct xfrm_tmpl *tmpl = &policy->xfrm_vec[i];
if (tmpl->mode == XFRM_MODE_TUNNEL ||
tmpl->mode == XFRM_MODE_BEET) {
remote = &tmpl->id.daddr;
local = &tmpl->saddr;
if (xfrm_addr_any(local, tmpl->encap_family)) {
error = xfrm_get_saddr(net, fl->flowi_oif,
&tmp, remote,
tmpl->encap_family, 0);
if (error)
goto fail;
local = &tmp;
}
}
x = xfrm_state_find(remote, local, fl, tmpl, policy, &error,
family, policy->if_id);
if (x && x->dir && x->dir != XFRM_SA_DIR_OUT) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTSTATEDIRERROR);
xfrm_state_put(x);
error = -EINVAL;
goto fail;
}
if (x && x->km.state == XFRM_STATE_VALID) {
xfrm[nx++] = x;
daddr = remote;
saddr = local;
continue;
}
if (x) {
error = (x->km.state == XFRM_STATE_ERROR ?
-EINVAL : -EAGAIN);
xfrm_state_put(x);
} else if (error == -ESRCH) {
error = -EAGAIN;
}
if (!tmpl->optional)
goto fail;
}
return nx;
fail:
for (nx--; nx >= 0; nx--)
xfrm_state_put(xfrm[nx]);
return error;
}
static int
xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
struct xfrm_state **xfrm, unsigned short family)
{
struct xfrm_state *tp[XFRM_MAX_DEPTH];
struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
int cnx = 0;
int error;
int ret;
int i;
for (i = 0; i < npols; i++) {
if (cnx + pols[i]->xfrm_nr >= XFRM_MAX_DEPTH) {
error = -ENOBUFS;
goto fail;
}
ret = xfrm_tmpl_resolve_one(pols[i], fl, &tpp[cnx], family);
if (ret < 0) {
error = ret;
goto fail;
} else
cnx += ret;
}
/* found states are sorted for outbound processing */
if (npols > 1)
xfrm_state_sort(xfrm, tpp, cnx, family);
return cnx;
fail:
for (cnx--; cnx >= 0; cnx--)
xfrm_state_put(tpp[cnx]);
return error;
}
static int xfrm_get_tos(const struct flowi *fl, int family)
{
if (family == AF_INET)
return fl->u.ip4.flowi4_tos & INET_DSCP_MASK;
return 0;
}
static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
{
const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
struct dst_ops *dst_ops;
struct xfrm_dst *xdst;
if (!afinfo)
return ERR_PTR(-EINVAL);
switch (family) {
case AF_INET:
dst_ops = &net->xfrm.xfrm4_dst_ops;
break;
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
dst_ops = &net->xfrm.xfrm6_dst_ops;
break;
#endif
default:
BUG();
}
xdst = dst_alloc(dst_ops, NULL, DST_OBSOLETE_NONE, 0);
if (likely(xdst)) {
memset_after(xdst, 0, u.dst);
} else
xdst = ERR_PTR(-ENOBUFS);
rcu_read_unlock();
return xdst;
}
static void xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
int nfheader_len)
{
if (dst->ops->family == AF_INET6) {
path->path_cookie = rt6_get_cookie(dst_rt6_info(dst));
path->u.rt6.rt6i_nfheader_len = nfheader_len;
}
}
static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
const struct flowi *fl)
{
const struct xfrm_policy_afinfo *afinfo =
xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
int err;
if (!afinfo)
return -EINVAL;
err = afinfo->fill_dst(xdst, dev, fl);
rcu_read_unlock();
return err;
}
/* Allocate chain of dst_entry's, attach known xfrm's, calculate
* all the metrics... Shortly, bundle a bundle.
*/
static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
struct xfrm_state **xfrm,
struct xfrm_dst **bundle,
int nx,
const struct flowi *fl,
struct dst_entry *dst)
{
const struct xfrm_state_afinfo *afinfo;
const struct xfrm_mode *inner_mode;
struct net *net = xp_net(policy);
unsigned long now = jiffies;
struct net_device *dev;
struct xfrm_dst *xdst_prev = NULL;
struct xfrm_dst *xdst0 = NULL;
int i = 0;
int err;
int header_len = 0;
int nfheader_len = 0;
int trailer_len = 0;
int tos;
int family = policy->selector.family;
xfrm_address_t saddr, daddr;
xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
tos = xfrm_get_tos(fl, family);
dst_hold(dst);
for (; i < nx; i++) {
struct xfrm_dst *xdst = xfrm_alloc_dst(net, family);
struct dst_entry *dst1 = &xdst->u.dst;
err = PTR_ERR(xdst);
if (IS_ERR(xdst)) {
dst_release(dst);
goto put_states;
}
bundle[i] = xdst;
if (!xdst_prev)
xdst0 = xdst;
else
/* Ref count is taken during xfrm_alloc_dst()
* No need to do dst_clone() on dst1
*/
xfrm_dst_set_child(xdst_prev, &xdst->u.dst);
if (xfrm[i]->sel.family == AF_UNSPEC) {
inner_mode = xfrm_ip2inner_mode(xfrm[i],
xfrm_af2proto(family));
if (!inner_mode) {
err = -EAFNOSUPPORT;
dst_release(dst);
goto put_states;
}
} else
inner_mode = &xfrm[i]->inner_mode;
xdst->route = dst;
dst_copy_metrics(dst1, dst);
if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
__u32 mark = 0;
int oif;
if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m)
mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]);
if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET)
family = xfrm[i]->props.family;
oif = fl->flowi_oif ? : fl->flowi_l3mdev;
dst = xfrm_dst_lookup(xfrm[i], tos, oif,
&saddr, &daddr, family, mark);
err = PTR_ERR(dst);
if (IS_ERR(dst))
goto put_states;
} else
dst_hold(dst);
dst1->xfrm = xfrm[i];
xdst->xfrm_genid = xfrm[i]->genid;
dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
dst1->lastuse = now;
dst1->input = dst_discard;
rcu_read_lock();
afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family);
if (likely(afinfo))
dst1->output = afinfo->output;
else
dst1->output = dst_discard_out;
rcu_read_unlock();
xdst_prev = xdst;
header_len += xfrm[i]->props.header_len;
if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
nfheader_len += xfrm[i]->props.header_len;
trailer_len += xfrm[i]->props.trailer_len;
}
xfrm_dst_set_child(xdst_prev, dst);
xdst0->path = dst;
err = -ENODEV;
dev = dst->dev;
if (!dev)
goto free_dst;
xfrm_init_path(xdst0, dst, nfheader_len);
xfrm_init_pmtu(bundle, nx);
for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst;
xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) {
err = xfrm_fill_dst(xdst_prev, dev, fl);
if (err)
goto free_dst;
xdst_prev->u.dst.header_len = header_len;
xdst_prev->u.dst.trailer_len = trailer_len;
header_len -= xdst_prev->u.dst.xfrm->props.header_len;
trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len;
}
return &xdst0->u.dst;
put_states:
for (; i < nx; i++)
xfrm_state_put(xfrm[i]);
free_dst:
if (xdst0)
dst_release_immediate(&xdst0->u.dst);
return ERR_PTR(err);
}
static int xfrm_expand_policies(const struct flowi *fl, u16 family,
struct xfrm_policy **pols,
int *num_pols, int *num_xfrms)
{
int i;
if (*num_pols == 0 || !pols[0]) {
*num_pols = 0;
*num_xfrms = 0;
return 0;
}
if (IS_ERR(pols[0])) {
*num_pols = 0;
return PTR_ERR(pols[0]);
}
*num_xfrms = pols[0]->xfrm_nr;
#ifdef CONFIG_XFRM_SUB_POLICY
if (pols[0]->action == XFRM_POLICY_ALLOW &&
pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]),
XFRM_POLICY_TYPE_MAIN,
fl, family,
XFRM_POLICY_OUT,
pols[0]->if_id);
if (pols[1]) {
if (IS_ERR(pols[1])) {
xfrm_pols_put(pols, *num_pols);
*num_pols = 0;
return PTR_ERR(pols[1]);
}
(*num_pols)++;
(*num_xfrms) += pols[1]->xfrm_nr;
}
}
#endif
for (i = 0; i < *num_pols; i++) {
if (pols[i]->action != XFRM_POLICY_ALLOW) {
*num_xfrms = -1;
break;
}
}
return 0;
}
static struct xfrm_dst *
xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
const struct flowi *fl, u16 family,
struct dst_entry *dst_orig)
{
struct net *net = xp_net(pols[0]);
struct xfrm_state *xfrm[XFRM_MAX_DEPTH];
struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
struct xfrm_dst *xdst;
struct dst_entry *dst;
int err;
/* Try to instantiate a bundle */
err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
if (err <= 0) {
if (err == 0)
return NULL;
if (err != -EAGAIN)
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
return ERR_PTR(err);
}
dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig);
if (IS_ERR(dst)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR);
return ERR_CAST(dst);
}
xdst = (struct xfrm_dst *)dst;
xdst->num_xfrms = err;
xdst->num_pols = num_pols;
memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
xdst->policy_genid = atomic_read(&pols[0]->genid);
return xdst;
}
static void xfrm_policy_queue_process(struct timer_list *t)
{
struct sk_buff *skb;
struct sock *sk;
struct dst_entry *dst;
struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer);
struct net *net = xp_net(pol);
struct xfrm_policy_queue *pq = &pol->polq;
struct flowi fl;
struct sk_buff_head list;
__u32 skb_mark;
spin_lock(&pq->hold_queue.lock);
skb = skb_peek(&pq->hold_queue);
if (!skb) {
spin_unlock(&pq->hold_queue.lock);
goto out;
}
dst = skb_dst(skb);
sk = skb->sk;
/* Fixup the mark to support VTI. */
skb_mark = skb->mark;
skb->mark = pol->mark.v;
xfrm_decode_session(net, skb, &fl, dst->ops->family);
skb->mark = skb_mark;
spin_unlock(&pq->hold_queue.lock);
dst_hold(xfrm_dst_path(dst));
dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE);
if (IS_ERR(dst))
goto purge_queue;
if (dst->flags & DST_XFRM_QUEUE) {
dst_release(dst);
if (pq->timeout >= XFRM_QUEUE_TMO_MAX)
goto purge_queue;
pq->timeout = pq->timeout << 1;
if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout))
xfrm_pol_hold(pol);
goto out;
}
dst_release(dst);
__skb_queue_head_init(&list);
spin_lock(&pq->hold_queue.lock);
pq->timeout = 0;
skb_queue_splice_init(&pq->hold_queue, &list);
spin_unlock(&pq->hold_queue.lock);
while (!skb_queue_empty(&list)) {
skb = __skb_dequeue(&list);
/* Fixup the mark to support VTI. */
skb_mark = skb->mark;
skb->mark = pol->mark.v;
xfrm_decode_session(net, skb, &fl, skb_dst(skb)->ops->family);
skb->mark = skb_mark;
dst_hold(xfrm_dst_path(skb_dst(skb)));
dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0);
if (IS_ERR(dst)) {
kfree_skb(skb);
continue;
}
nf_reset_ct(skb);
skb_dst_drop(skb);
skb_dst_set(skb, dst);
dst_output(net, skb->sk, skb);
}
out:
xfrm_pol_put(pol);
return;
purge_queue:
pq->timeout = 0;
skb_queue_purge(&pq->hold_queue);
xfrm_pol_put(pol);
}
static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
unsigned long sched_next;
struct dst_entry *dst = skb_dst(skb);
struct xfrm_dst *xdst = (struct xfrm_dst *) dst;
struct xfrm_policy *pol = xdst->pols[0];
struct xfrm_policy_queue *pq = &pol->polq;
if (unlikely(skb_fclone_busy(sk, skb))) {
kfree_skb(skb);
return 0;
}
if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) {
kfree_skb(skb);
return -EAGAIN;
}
skb_dst_force(skb);
spin_lock_bh(&pq->hold_queue.lock);
if (!pq->timeout)
pq->timeout = XFRM_QUEUE_TMO_MIN;
sched_next = jiffies + pq->timeout;
if (del_timer(&pq->hold_timer)) {
if (time_before(pq->hold_timer.expires, sched_next))
sched_next = pq->hold_timer.expires;
xfrm_pol_put(pol);
}
__skb_queue_tail(&pq->hold_queue, skb);
if (!mod_timer(&pq->hold_timer, sched_next))
xfrm_pol_hold(pol);
spin_unlock_bh(&pq->hold_queue.lock);
return 0;
}
static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net,
struct xfrm_flo *xflo,
const struct flowi *fl,
int num_xfrms,
u16 family)
{
int err;
struct net_device *dev;
struct dst_entry *dst;
struct dst_entry *dst1;
struct xfrm_dst *xdst;
xdst = xfrm_alloc_dst(net, family);
if (IS_ERR(xdst))
return xdst;
if (!(xflo->flags & XFRM_LOOKUP_QUEUE) ||
net->xfrm.sysctl_larval_drop ||
num_xfrms <= 0)
return xdst;
dst = xflo->dst_orig;
dst1 = &xdst->u.dst;
dst_hold(dst);
xdst->route = dst;
dst_copy_metrics(dst1, dst);
dst1->obsolete = DST_OBSOLETE_FORCE_CHK;
dst1->flags |= DST_XFRM_QUEUE;
dst1->lastuse = jiffies;
dst1->input = dst_discard;
dst1->output = xdst_queue_output;
dst_hold(dst);
xfrm_dst_set_child(xdst, dst);
xdst->path = dst;
xfrm_init_path((struct xfrm_dst *)dst1, dst, 0);
err = -ENODEV;
dev = dst->dev;
if (!dev)
goto free_dst;
err = xfrm_fill_dst(xdst, dev, fl);
if (err)
goto free_dst;
out:
return xdst;
free_dst:
dst_release(dst1);
xdst = ERR_PTR(err);
goto out;
}
static struct xfrm_dst *xfrm_bundle_lookup(struct net *net,
const struct flowi *fl,
u16 family, u8 dir,
struct xfrm_flo *xflo, u32 if_id)
{
struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
int num_pols = 0, num_xfrms = 0, err;
struct xfrm_dst *xdst;
/* Resolve policies to use if we couldn't get them from
* previous cache entry */
num_pols = 1;
pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id);
err = xfrm_expand_policies(fl, family, pols,
&num_pols, &num_xfrms);
if (err < 0)
goto inc_error;
if (num_pols == 0)
return NULL;
if (num_xfrms <= 0)
goto make_dummy_bundle;
xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family,
xflo->dst_orig);
if (IS_ERR(xdst)) {
err = PTR_ERR(xdst);
if (err == -EREMOTE) {
xfrm_pols_put(pols, num_pols);
return NULL;
}
if (err != -EAGAIN)
goto error;
goto make_dummy_bundle;
} else if (xdst == NULL) {
num_xfrms = 0;
goto make_dummy_bundle;
}
return xdst;
make_dummy_bundle:
/* We found policies, but there's no bundles to instantiate:
* either because the policy blocks, has no transformations or
* we could not build template (no xfrm_states).*/
xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family);
if (IS_ERR(xdst)) {
xfrm_pols_put(pols, num_pols);
return ERR_CAST(xdst);
}
xdst->num_pols = num_pols;
xdst->num_xfrms = num_xfrms;
memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols);
return xdst;
inc_error:
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
error:
xfrm_pols_put(pols, num_pols);
return ERR_PTR(err);
}
static struct dst_entry *make_blackhole(struct net *net, u16 family,
struct dst_entry *dst_orig)
{
const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
struct dst_entry *ret;
if (!afinfo) {
dst_release(dst_orig);
return ERR_PTR(-EINVAL);
} else {
ret = afinfo->blackhole_route(net, dst_orig);
}
rcu_read_unlock();
return ret;
}
/* Finds/creates a bundle for given flow and if_id
*
* At the moment we eat a raw IP route. Mostly to speed up lookups
* on interfaces with disabled IPsec.
*
* xfrm_lookup uses an if_id of 0 by default, and is provided for
* compatibility
*/
struct dst_entry *xfrm_lookup_with_ifid(struct net *net,
struct dst_entry *dst_orig,
const struct flowi *fl,
const struct sock *sk,
int flags, u32 if_id)
{
struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
struct xfrm_dst *xdst;
struct dst_entry *dst, *route;
u16 family = dst_orig->ops->family;
u8 dir = XFRM_POLICY_OUT;
int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
dst = NULL;
xdst = NULL;
route = NULL;
sk = sk_const_to_full_sk(sk);
if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
num_pols = 1;
pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family,
if_id);
err = xfrm_expand_policies(fl, family, pols,
&num_pols, &num_xfrms);
if (err < 0)
goto dropdst;
if (num_pols) {
if (num_xfrms <= 0) {
drop_pols = num_pols;
goto no_transform;
}
xdst = xfrm_resolve_and_create_bundle(
pols, num_pols, fl,
family, dst_orig);
if (IS_ERR(xdst)) {
xfrm_pols_put(pols, num_pols);
err = PTR_ERR(xdst);
if (err == -EREMOTE)
goto nopol;
goto dropdst;
} else if (xdst == NULL) {
num_xfrms = 0;
drop_pols = num_pols;
goto no_transform;
}
route = xdst->route;
}
}
if (xdst == NULL) {
struct xfrm_flo xflo;
xflo.dst_orig = dst_orig;
xflo.flags = flags;
/* To accelerate a bit... */
if (!if_id && ((dst_orig->flags & DST_NOXFRM) ||
!net->xfrm.policy_count[XFRM_POLICY_OUT]))
goto nopol;
xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id);
if (xdst == NULL)
goto nopol;
if (IS_ERR(xdst)) {
err = PTR_ERR(xdst);
goto dropdst;
}
num_pols = xdst->num_pols;
num_xfrms = xdst->num_xfrms;
memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols);
route = xdst->route;
}
dst = &xdst->u.dst;
if (route == NULL && num_xfrms > 0) {
/* The only case when xfrm_bundle_lookup() returns a
* bundle with null route, is when the template could
* not be resolved. It means policies are there, but
* bundle could not be created, since we don't yet
* have the xfrm_state's. We need to wait for KM to
* negotiate new SA's or bail out with error.*/
if (net->xfrm.sysctl_larval_drop) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
err = -EREMOTE;
goto error;
}
err = -EAGAIN;
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
goto error;
}
no_transform:
if (num_pols == 0)
goto nopol;
if ((flags & XFRM_LOOKUP_ICMP) &&
!(pols[0]->flags & XFRM_POLICY_ICMP)) {
err = -ENOENT;
goto error;
}
for (i = 0; i < num_pols; i++)
WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds());
if (num_xfrms < 0) {
/* Prohibit the flow */
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK);
err = -EPERM;
goto error;
} else if (num_xfrms > 0) {
/* Flow transformed */
dst_release(dst_orig);
} else {
/* Flow passes untransformed */
dst_release(dst);
dst = dst_orig;
}
ok:
xfrm_pols_put(pols, drop_pols);
if (dst && dst->xfrm &&
dst->xfrm->props.mode == XFRM_MODE_TUNNEL)
dst->flags |= DST_XFRM_TUNNEL;
return dst;
nopol:
if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) &&
net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
err = -EPERM;
goto error;
}
if (!(flags & XFRM_LOOKUP_ICMP)) {
dst = dst_orig;
goto ok;
}
err = -ENOENT;
error:
dst_release(dst);
dropdst:
if (!(flags & XFRM_LOOKUP_KEEP_DST_REF))
dst_release(dst_orig);
xfrm_pols_put(pols, drop_pols);
return ERR_PTR(err);
}
EXPORT_SYMBOL(xfrm_lookup_with_ifid);
/* Main function: finds/creates a bundle for given flow.
*
* At the moment we eat a raw IP route. Mostly to speed up lookups
* on interfaces with disabled IPsec.
*/
struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
const struct flowi *fl, const struct sock *sk,
int flags)
{
return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0);
}
EXPORT_SYMBOL(xfrm_lookup);
/* Callers of xfrm_lookup_route() must ensure a call to dst_output().
* Otherwise we may send out blackholed packets.
*/
struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
const struct flowi *fl,
const struct sock *sk, int flags)
{
struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk,
flags | XFRM_LOOKUP_QUEUE |
XFRM_LOOKUP_KEEP_DST_REF);
if (PTR_ERR(dst) == -EREMOTE)
return make_blackhole(net, dst_orig->ops->family, dst_orig);
if (IS_ERR(dst))
dst_release(dst_orig);
return dst;
}
EXPORT_SYMBOL(xfrm_lookup_route);
static inline int
xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
{
struct sec_path *sp = skb_sec_path(skb);
struct xfrm_state *x;
if (!sp || idx < 0 || idx >= sp->len)
return 0;
x = sp->xvec[idx];
if (!x->type->reject)
return 0;
return x->type->reject(x, skb, fl);
}
/* When skb is transformed back to its "native" form, we have to
* check policy restrictions. At the moment we make this in maximally
* stupid way. Shame on me. :-) Of course, connected sockets must
* have policy cached at them.
*/
static inline int
xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
unsigned short family, u32 if_id)
{
if (xfrm_state_kern(x))
return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family);
return x->id.proto == tmpl->id.proto &&
(x->id.spi == tmpl->id.spi || !tmpl->id.spi) &&
(x->props.reqid == tmpl->reqid || !tmpl->reqid) &&
x->props.mode == tmpl->mode &&
(tmpl->allalgs || (tmpl->aalgos & (1<<x->props.aalgo)) ||
!(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) &&
!(x->props.mode != XFRM_MODE_TRANSPORT &&
xfrm_state_addr_cmp(tmpl, x, family)) &&
(if_id == 0 || if_id == x->if_id);
}
/*
* 0 or more than 0 is returned when validation is succeeded (either bypass
* because of optional transport mode, or next index of the matched secpath
* state with the template.
* -1 is returned when no matching template is found.
* Otherwise "-2 - errored_index" is returned.
*/
static inline int
xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
unsigned short family, u32 if_id)
{
int idx = start;
if (tmpl->optional) {
if (tmpl->mode == XFRM_MODE_TRANSPORT)
return start;
} else
start = -1;
for (; idx < sp->len; idx++) {
if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id))
return ++idx;
if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) {
if (idx < sp->verified_cnt) {
/* Secpath entry previously verified, consider optional and
* continue searching
*/
continue;
}
if (start == -1)
start = -2-idx;
break;
}
}
return start;
}
static void
decode_session4(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
{
struct flowi4 *fl4 = &fl->u.ip4;
memset(fl4, 0, sizeof(struct flowi4));
if (reverse) {
fl4->saddr = flkeys->addrs.ipv4.dst;
fl4->daddr = flkeys->addrs.ipv4.src;
fl4->fl4_sport = flkeys->ports.dst;
fl4->fl4_dport = flkeys->ports.src;
} else {
fl4->saddr = flkeys->addrs.ipv4.src;
fl4->daddr = flkeys->addrs.ipv4.dst;
fl4->fl4_sport = flkeys->ports.src;
fl4->fl4_dport = flkeys->ports.dst;
}
switch (flkeys->basic.ip_proto) {
case IPPROTO_GRE:
fl4->fl4_gre_key = flkeys->gre.keyid;
break;
case IPPROTO_ICMP:
fl4->fl4_icmp_type = flkeys->icmp.type;
fl4->fl4_icmp_code = flkeys->icmp.code;
break;
}
fl4->flowi4_proto = flkeys->basic.ip_proto;
fl4->flowi4_tos = flkeys->ip.tos & ~INET_ECN_MASK;
}
#if IS_ENABLED(CONFIG_IPV6)
static void
decode_session6(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse)
{
struct flowi6 *fl6 = &fl->u.ip6;
memset(fl6, 0, sizeof(struct flowi6));
if (reverse) {
fl6->saddr = flkeys->addrs.ipv6.dst;
fl6->daddr = flkeys->addrs.ipv6.src;
fl6->fl6_sport = flkeys->ports.dst;
fl6->fl6_dport = flkeys->ports.src;
} else {
fl6->saddr = flkeys->addrs.ipv6.src;
fl6->daddr = flkeys->addrs.ipv6.dst;
fl6->fl6_sport = flkeys->ports.src;
fl6->fl6_dport = flkeys->ports.dst;
}
switch (flkeys->basic.ip_proto) {
case IPPROTO_GRE:
fl6->fl6_gre_key = flkeys->gre.keyid;
break;
case IPPROTO_ICMPV6:
fl6->fl6_icmp_type = flkeys->icmp.type;
fl6->fl6_icmp_code = flkeys->icmp.code;
break;
}
fl6->flowi6_proto = flkeys->basic.ip_proto;
}
#endif
int __xfrm_decode_session(struct net *net, struct sk_buff *skb, struct flowi *fl,
unsigned int family, int reverse)
{
struct xfrm_flow_keys flkeys;
memset(&flkeys, 0, sizeof(flkeys));
__skb_flow_dissect(net, skb, &xfrm_session_dissector, &flkeys,
NULL, 0, 0, 0, FLOW_DISSECTOR_F_STOP_AT_ENCAP);
switch (family) {
case AF_INET:
decode_session4(&flkeys, fl, reverse);
break;
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
decode_session6(&flkeys, fl, reverse);
break;
#endif
default:
return -EAFNOSUPPORT;
}
fl->flowi_mark = skb->mark;
if (reverse) {
fl->flowi_oif = skb->skb_iif;
} else {
int oif = 0;
if (skb_dst(skb) && skb_dst(skb)->dev)
oif = skb_dst(skb)->dev->ifindex;
fl->flowi_oif = oif;
}
return security_xfrm_decode_session(skb, &fl->flowi_secid);
}
EXPORT_SYMBOL(__xfrm_decode_session);
static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
{
for (; k < sp->len; k++) {
if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
*idxp = k;
return 1;
}
}
return 0;
}
static bool icmp_err_packet(const struct flowi *fl, unsigned short family)
{
const struct flowi4 *fl4 = &fl->u.ip4;
if (family == AF_INET &&
fl4->flowi4_proto == IPPROTO_ICMP &&
(fl4->fl4_icmp_type == ICMP_DEST_UNREACH ||
fl4->fl4_icmp_type == ICMP_TIME_EXCEEDED))
return true;
#if IS_ENABLED(CONFIG_IPV6)
if (family == AF_INET6) {
const struct flowi6 *fl6 = &fl->u.ip6;
if (fl6->flowi6_proto == IPPROTO_ICMPV6 &&
(fl6->fl6_icmp_type == ICMPV6_DEST_UNREACH ||
fl6->fl6_icmp_type == ICMPV6_PKT_TOOBIG ||
fl6->fl6_icmp_type == ICMPV6_TIME_EXCEED))
return true;
}
#endif
return false;
}
static bool xfrm_icmp_flow_decode(struct sk_buff *skb, unsigned short family,
const struct flowi *fl, struct flowi *fl1)
{
bool ret = true;
struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
int hl = family == AF_INET ? (sizeof(struct iphdr) + sizeof(struct icmphdr)) :
(sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr));
if (!newskb)
return true;
if (!pskb_pull(newskb, hl))
goto out;
skb_reset_network_header(newskb);
if (xfrm_decode_session_reverse(dev_net(skb->dev), newskb, fl1, family) < 0)
goto out;
fl1->flowi_oif = fl->flowi_oif;
fl1->flowi_mark = fl->flowi_mark;
fl1->flowi_tos = fl->flowi_tos;
nf_nat_decode_session(newskb, fl1, family);
ret = false;
out:
consume_skb(newskb);
return ret;
}
static bool xfrm_selector_inner_icmp_match(struct sk_buff *skb, unsigned short family,
const struct xfrm_selector *sel,
const struct flowi *fl)
{
bool ret = false;
if (icmp_err_packet(fl, family)) {
struct flowi fl1;
if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
return ret;
ret = xfrm_selector_match(sel, &fl1, family);
}
return ret;
}
static inline struct
xfrm_policy *xfrm_in_fwd_icmp(struct sk_buff *skb,
const struct flowi *fl, unsigned short family,
u32 if_id)
{
struct xfrm_policy *pol = NULL;
if (icmp_err_packet(fl, family)) {
struct flowi fl1;
struct net *net = dev_net(skb->dev);
if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
return pol;
pol = xfrm_policy_lookup(net, &fl1, family, XFRM_POLICY_FWD, if_id);
if (IS_ERR(pol))
pol = NULL;
}
return pol;
}
static inline struct
dst_entry *xfrm_out_fwd_icmp(struct sk_buff *skb, struct flowi *fl,
unsigned short family, struct dst_entry *dst)
{
if (icmp_err_packet(fl, family)) {
struct net *net = dev_net(skb->dev);
struct dst_entry *dst2;
struct flowi fl1;
if (xfrm_icmp_flow_decode(skb, family, fl, &fl1))
return dst;
dst_hold(dst);
dst2 = xfrm_lookup(net, dst, &fl1, NULL, (XFRM_LOOKUP_QUEUE | XFRM_LOOKUP_ICMP));
if (IS_ERR(dst2))
return dst;
if (dst2->xfrm) {
dst_release(dst);
dst = dst2;
} else {
dst_release(dst2);
}
}
return dst;
}
int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb,
unsigned short family)
{
struct net *net = dev_net(skb->dev);
struct xfrm_policy *pol;
struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
int npols = 0;
int xfrm_nr;
int pi;
int reverse;
struct flowi fl;
int xerr_idx = -1;
const struct xfrm_if_cb *ifcb;
struct sec_path *sp;
u32 if_id = 0;
rcu_read_lock();
ifcb = xfrm_if_get_cb();
if (ifcb) {
struct xfrm_if_decode_session_result r;
if (ifcb->decode_session(skb, family, &r)) {
if_id = r.if_id;
net = r.net;
}
}
rcu_read_unlock();
reverse = dir & ~XFRM_POLICY_MASK;
dir &= XFRM_POLICY_MASK;
if (__xfrm_decode_session(net, skb, &fl, family, reverse) < 0) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
return 0;
}
nf_nat_decode_session(skb, &fl, family);
/* First, check used SA against their selectors. */
sp = skb_sec_path(skb);
if (sp) {
int i;
for (i = sp->len - 1; i >= 0; i--) {
struct xfrm_state *x = sp->xvec[i];
int ret = 0;
if (!xfrm_selector_match(&x->sel, &fl, family)) {
ret = 1;
if (x->props.flags & XFRM_STATE_ICMP &&
xfrm_selector_inner_icmp_match(skb, family, &x->sel, &fl))
ret = 0;
if (ret) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
return 0;
}
}
}
}
pol = NULL;
sk = sk_to_full_sk(sk);
if (sk && sk->sk_policy[dir]) {
pol = xfrm_sk_policy_lookup(sk, dir, &fl, family, if_id);
if (IS_ERR(pol)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
return 0;
}
}
if (!pol)
pol = xfrm_policy_lookup(net, &fl, family, dir, if_id);
if (IS_ERR(pol)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
return 0;
}
if (!pol && dir == XFRM_POLICY_FWD)
pol = xfrm_in_fwd_icmp(skb, &fl, family, if_id);
if (!pol) {
const bool is_crypto_offload = sp &&
(xfrm_input_state(skb)->xso.type == XFRM_DEV_OFFLOAD_CRYPTO);
if (net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
return 0;
}
if (sp && secpath_has_nontransport(sp, 0, &xerr_idx) && !is_crypto_offload) {
xfrm_secpath_reject(xerr_idx, skb, &fl);
XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOPOLS);
return 0;
}
return 1;
}
/* This lockless write can happen from different cpus. */
WRITE_ONCE(pol->curlft.use_time, ktime_get_real_seconds());
pols[0] = pol;
npols++;
#ifdef CONFIG_XFRM_SUB_POLICY
if (pols[0]->type != XFRM_POLICY_TYPE_MAIN) {
pols[1] = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN,
&fl, family,
XFRM_POLICY_IN, if_id);
if (pols[1]) {
if (IS_ERR(pols[1])) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
xfrm_pol_put(pols[0]);
return 0;
}
/* This write can happen from different cpus. */
WRITE_ONCE(pols[1]->curlft.use_time,
ktime_get_real_seconds());
npols++;
}
}
#endif
if (pol->action == XFRM_POLICY_ALLOW) {
static struct sec_path dummy;
struct xfrm_tmpl *tp[XFRM_MAX_DEPTH];
struct xfrm_tmpl *stp[XFRM_MAX_DEPTH];
struct xfrm_tmpl **tpp = tp;
int ti = 0;
int i, k;
sp = skb_sec_path(skb);
if (!sp)
sp = &dummy;
for (pi = 0; pi < npols; pi++) {
if (pols[pi] != pol &&
pols[pi]->action != XFRM_POLICY_ALLOW) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
goto reject;
}
if (ti + pols[pi]->xfrm_nr >= XFRM_MAX_DEPTH) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
goto reject_error;
}
for (i = 0; i < pols[pi]->xfrm_nr; i++)
tpp[ti++] = &pols[pi]->xfrm_vec[i];
}
xfrm_nr = ti;
if (npols > 1) {
xfrm_tmpl_sort(stp, tpp, xfrm_nr, family);
tpp = stp;
}
/* For each tunnel xfrm, find the first matching tmpl.
* For each tmpl before that, find corresponding xfrm.
* Order is _important_. Later we will implement
* some barriers, but at the moment barriers
* are implied between each two transformations.
* Upon success, marks secpath entries as having been
* verified to allow them to be skipped in future policy
* checks (e.g. nested tunnels).
*/
for (i = xfrm_nr-1, k = 0; i >= 0; i--) {
k = xfrm_policy_ok(tpp[i], sp, k, family, if_id);
if (k < 0) {
if (k < -1)
/* "-2 - errored_index" returned */
xerr_idx = -(2+k);
XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
goto reject;
}
}
if (secpath_has_nontransport(sp, k, &xerr_idx)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMINTMPLMISMATCH);
goto reject;
}
xfrm_pols_put(pols, npols);
sp->verified_cnt = k;
return 1;
}
XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLBLOCK);
reject:
xfrm_secpath_reject(xerr_idx, skb, &fl);
reject_error:
xfrm_pols_put(pols, npols);
return 0;
}
EXPORT_SYMBOL(__xfrm_policy_check);
int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
{
struct net *net = dev_net(skb->dev);
struct flowi fl;
struct dst_entry *dst;
int res = 1;
if (xfrm_decode_session(net, skb, &fl, family) < 0) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
return 0;
}
skb_dst_force(skb);
if (!skb_dst(skb)) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
return 0;
}
dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE);
if (IS_ERR(dst)) {
res = 0;
dst = NULL;
}
if (dst && !dst->xfrm)
dst = xfrm_out_fwd_icmp(skb, &fl, family, dst);
skb_dst_set(skb, dst);
return res;
}
EXPORT_SYMBOL(__xfrm_route_forward);
/* Optimize later using cookies and generation ids. */
static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
{
/* Code (such as __xfrm4_bundle_create()) sets dst->obsolete
* to DST_OBSOLETE_FORCE_CHK to force all XFRM destinations to
* get validated by dst_ops->check on every use. We do this
* because when a normal route referenced by an XFRM dst is
* obsoleted we do not go looking around for all parent
* referencing XFRM dsts so that we can invalidate them. It
* is just too much work. Instead we make the checks here on
* every use. For example:
*
* XFRM dst A --> IPv4 dst X
*
* X is the "xdst->route" of A (X is also the "dst->path" of A
* in this example). If X is marked obsolete, "A" will not
* notice. That's what we are validating here via the
* stale_bundle() check.
*
* When a dst is removed from the fib tree, DST_OBSOLETE_DEAD will
* be marked on it.
* This will force stale_bundle() to fail on any xdst bundle with
* this dst linked in it.
*/
if (dst->obsolete < 0 && !stale_bundle(dst))
return dst;
return NULL;
}
static int stale_bundle(struct dst_entry *dst)
{
return !xfrm_bundle_ok((struct xfrm_dst *)dst);
}
void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
{
while ((dst = xfrm_dst_child(dst)) && dst->xfrm && dst->dev == dev) {
dst->dev = blackhole_netdev;
dev_hold(dst->dev);
dev_put(dev);
}
}
EXPORT_SYMBOL(xfrm_dst_ifdown);
static void xfrm_link_failure(struct sk_buff *skb)
{
/* Impossible. Such dst must be popped before reaches point of failure. */
}
static void xfrm_negative_advice(struct sock *sk, struct dst_entry *dst)
{
if (dst->obsolete)
sk_dst_reset(sk);
}
static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr)
{
while (nr--) {
struct xfrm_dst *xdst = bundle[nr];
u32 pmtu, route_mtu_cached;
struct dst_entry *dst;
dst = &xdst->u.dst;
pmtu = dst_mtu(xfrm_dst_child(dst));
xdst->child_mtu_cached = pmtu;
pmtu = xfrm_state_mtu(dst->xfrm, pmtu);
route_mtu_cached = dst_mtu(xdst->route);
xdst->route_mtu_cached = route_mtu_cached;
if (pmtu > route_mtu_cached)
pmtu = route_mtu_cached;
dst_metric_set(dst, RTAX_MTU, pmtu);
}
}
/* Check that the bundle accepts the flow and its components are
* still valid.
*/
static int xfrm_bundle_ok(struct xfrm_dst *first)
{
struct xfrm_dst *bundle[XFRM_MAX_DEPTH];
struct dst_entry *dst = &first->u.dst;
struct xfrm_dst *xdst;
int start_from, nr;
u32 mtu;
if (!dst_check(xfrm_dst_path(dst), ((struct xfrm_dst *)dst)->path_cookie) ||
(dst->dev && !netif_running(dst->dev)))
return 0;
if (dst->flags & DST_XFRM_QUEUE)
return 1;
start_from = nr = 0;
do {
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
if (dst->xfrm->km.state != XFRM_STATE_VALID)
return 0;
if (xdst->xfrm_genid != dst->xfrm->genid)
return 0;
if (xdst->num_pols > 0 &&
xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
return 0;
bundle[nr++] = xdst;
mtu = dst_mtu(xfrm_dst_child(dst));
if (xdst->child_mtu_cached != mtu) {
start_from = nr;
xdst->child_mtu_cached = mtu;
}
if (!dst_check(xdst->route, xdst->route_cookie))
return 0;
mtu = dst_mtu(xdst->route);
if (xdst->route_mtu_cached != mtu) {
start_from = nr;
xdst->route_mtu_cached = mtu;
}
dst = xfrm_dst_child(dst);
} while (dst->xfrm);
if (likely(!start_from))
return 1;
xdst = bundle[start_from - 1];
mtu = xdst->child_mtu_cached;
while (start_from--) {
dst = &xdst->u.dst;
mtu = xfrm_state_mtu(dst->xfrm, mtu);
if (mtu > xdst->route_mtu_cached)
mtu = xdst->route_mtu_cached;
dst_metric_set(dst, RTAX_MTU, mtu);
if (!start_from)
break;
xdst = bundle[start_from - 1];
xdst->child_mtu_cached = mtu;
}
return 1;
}
static unsigned int xfrm_default_advmss(const struct dst_entry *dst)
{
return dst_metric_advmss(xfrm_dst_path(dst));
}
static unsigned int xfrm_mtu(const struct dst_entry *dst)
{
unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
return mtu ? : dst_mtu(xfrm_dst_path(dst));
}
static const void *xfrm_get_dst_nexthop(const struct dst_entry *dst,
const void *daddr)
{
while (dst->xfrm) {
const struct xfrm_state *xfrm = dst->xfrm;
dst = xfrm_dst_child(dst);
if (xfrm->props.mode == XFRM_MODE_TRANSPORT)
continue;
if (xfrm->type->flags & XFRM_TYPE_REMOTE_COADDR)
daddr = xfrm->coaddr;
else if (!(xfrm->type->flags & XFRM_TYPE_LOCAL_COADDR))
daddr = &xfrm->id.daddr;
}
return daddr;
}
static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
struct sk_buff *skb,
const void *daddr)
{
const struct dst_entry *path = xfrm_dst_path(dst);
if (!skb)
daddr = xfrm_get_dst_nexthop(dst, daddr);
return path->ops->neigh_lookup(path, skb, daddr);
}
static void xfrm_confirm_neigh(const struct dst_entry *dst, const void *daddr)
{
const struct dst_entry *path = xfrm_dst_path(dst);
daddr = xfrm_get_dst_nexthop(dst, daddr);
path->ops->confirm_neigh(path, daddr);
}
int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
{
int err = 0;
if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
return -EAFNOSUPPORT;
spin_lock(&xfrm_policy_afinfo_lock);
if (unlikely(xfrm_policy_afinfo[family] != NULL))
err = -EEXIST;
else {
struct dst_ops *dst_ops = afinfo->dst_ops;
if (likely(dst_ops->kmem_cachep == NULL))
dst_ops->kmem_cachep = xfrm_dst_cache;
if (likely(dst_ops->check == NULL))
dst_ops->check = xfrm_dst_check;
if (likely(dst_ops->default_advmss == NULL))
dst_ops->default_advmss = xfrm_default_advmss;
if (likely(dst_ops->mtu == NULL))
dst_ops->mtu = xfrm_mtu;
if (likely(dst_ops->negative_advice == NULL))
dst_ops->negative_advice = xfrm_negative_advice;
if (likely(dst_ops->link_failure == NULL))
dst_ops->link_failure = xfrm_link_failure;
if (likely(dst_ops->neigh_lookup == NULL))
dst_ops->neigh_lookup = xfrm_neigh_lookup;
if (likely(!dst_ops->confirm_neigh))
dst_ops->confirm_neigh = xfrm_confirm_neigh;
rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
}
spin_unlock(&xfrm_policy_afinfo_lock);
return err;
}
EXPORT_SYMBOL(xfrm_policy_register_afinfo);
void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
{
struct dst_ops *dst_ops = afinfo->dst_ops;
int i;
for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
if (xfrm_policy_afinfo[i] != afinfo)
continue;
RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
break;
}
synchronize_rcu();
dst_ops->kmem_cachep = NULL;
dst_ops->check = NULL;
dst_ops->negative_advice = NULL;
dst_ops->link_failure = NULL;
}
EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
void xfrm_if_register_cb(const struct xfrm_if_cb *ifcb)
{
spin_lock(&xfrm_if_cb_lock);
rcu_assign_pointer(xfrm_if_cb, ifcb);
spin_unlock(&xfrm_if_cb_lock);
}
EXPORT_SYMBOL(xfrm_if_register_cb);
void xfrm_if_unregister_cb(void)
{
RCU_INIT_POINTER(xfrm_if_cb, NULL);
synchronize_rcu();
}
EXPORT_SYMBOL(xfrm_if_unregister_cb);
#ifdef CONFIG_XFRM_STATISTICS
static int __net_init xfrm_statistics_init(struct net *net)
{
int rv;
net->mib.xfrm_statistics = alloc_percpu(struct linux_xfrm_mib);
if (!net->mib.xfrm_statistics)
return -ENOMEM;
rv = xfrm_proc_init(net);
if (rv < 0)
free_percpu(net->mib.xfrm_statistics);
return rv;
}
static void xfrm_statistics_fini(struct net *net)
{
xfrm_proc_fini(net);
free_percpu(net->mib.xfrm_statistics);
}
#else
static int __net_init xfrm_statistics_init(struct net *net)
{
return 0;
}
static void xfrm_statistics_fini(struct net *net)
{
}
#endif
static int __net_init xfrm_policy_init(struct net *net)
{
unsigned int hmask, sz;
int dir, err;
if (net_eq(net, &init_net)) {
xfrm_dst_cache = KMEM_CACHE(xfrm_dst, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
err = rhashtable_init(&xfrm_policy_inexact_table,
&xfrm_pol_inexact_params);
BUG_ON(err);
}
hmask = 8 - 1;
sz = (hmask+1) * sizeof(struct hlist_head);
net->xfrm.policy_byidx = xfrm_hash_alloc(sz);
if (!net->xfrm.policy_byidx)
goto out_byidx;
net->xfrm.policy_idx_hmask = hmask;
for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
struct xfrm_policy_hash *htab;
net->xfrm.policy_count[dir] = 0;
net->xfrm.policy_count[XFRM_POLICY_MAX + dir] = 0;
INIT_HLIST_HEAD(&net->xfrm.policy_inexact[dir]);
htab = &net->xfrm.policy_bydst[dir];
htab->table = xfrm_hash_alloc(sz);
if (!htab->table)
goto out_bydst;
htab->hmask = hmask;
htab->dbits4 = 32;
htab->sbits4 = 32;
htab->dbits6 = 128;
htab->sbits6 = 128;
}
net->xfrm.policy_hthresh.lbits4 = 32;
net->xfrm.policy_hthresh.rbits4 = 32;
net->xfrm.policy_hthresh.lbits6 = 128;
net->xfrm.policy_hthresh.rbits6 = 128;
seqlock_init(&net->xfrm.policy_hthresh.lock);
INIT_LIST_HEAD(&net->xfrm.policy_all);
INIT_LIST_HEAD(&net->xfrm.inexact_bins);
INIT_WORK(&net->xfrm.policy_hash_work, xfrm_hash_resize);
INIT_WORK(&net->xfrm.policy_hthresh.work, xfrm_hash_rebuild);
return 0;
out_bydst:
for (dir--; dir >= 0; dir--) {
struct xfrm_policy_hash *htab;
htab = &net->xfrm.policy_bydst[dir];
xfrm_hash_free(htab->table, sz);
}
xfrm_hash_free(net->xfrm.policy_byidx, sz);
out_byidx:
return -ENOMEM;
}
static void xfrm_policy_fini(struct net *net)
{
struct xfrm_pol_inexact_bin *b, *t;
unsigned int sz;
int dir;
flush_work(&net->xfrm.policy_hash_work);
#ifdef CONFIG_XFRM_SUB_POLICY
xfrm_policy_flush(net, XFRM_POLICY_TYPE_SUB, false);
#endif
xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, false);
WARN_ON(!list_empty(&net->xfrm.policy_all));
for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
struct xfrm_policy_hash *htab;
WARN_ON(!hlist_empty(&net->xfrm.policy_inexact[dir]));
htab = &net->xfrm.policy_bydst[dir];
sz = (htab->hmask + 1) * sizeof(struct hlist_head);
WARN_ON(!hlist_empty(htab->table));
xfrm_hash_free(htab->table, sz);
}
sz = (net->xfrm.policy_idx_hmask + 1) * sizeof(struct hlist_head);
WARN_ON(!hlist_empty(net->xfrm.policy_byidx));
xfrm_hash_free(net->xfrm.policy_byidx, sz);
spin_lock_bh(&net->xfrm.xfrm_policy_lock);
list_for_each_entry_safe(b, t, &net->xfrm.inexact_bins, inexact_bins)
__xfrm_policy_inexact_prune_bin(b, true);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
}
static int __net_init xfrm_net_init(struct net *net)
{
int rv;
/* Initialize the per-net locks here */
spin_lock_init(&net->xfrm.xfrm_state_lock);
spin_lock_init(&net->xfrm.xfrm_policy_lock);
seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
mutex_init(&net->xfrm.xfrm_cfg_mutex);
net->xfrm.policy_default[XFRM_POLICY_IN] = XFRM_USERPOLICY_ACCEPT;
net->xfrm.policy_default[XFRM_POLICY_FWD] = XFRM_USERPOLICY_ACCEPT;
net->xfrm.policy_default[XFRM_POLICY_OUT] = XFRM_USERPOLICY_ACCEPT;
rv = xfrm_statistics_init(net);
if (rv < 0)
goto out_statistics;
rv = xfrm_state_init(net);
if (rv < 0)
goto out_state;
rv = xfrm_policy_init(net);
if (rv < 0)
goto out_policy;
rv = xfrm_sysctl_init(net);
if (rv < 0)
goto out_sysctl;
rv = xfrm_nat_keepalive_net_init(net);
if (rv < 0)
goto out_nat_keepalive;
return 0;
out_nat_keepalive:
xfrm_sysctl_fini(net);
out_sysctl:
xfrm_policy_fini(net);
out_policy:
xfrm_state_fini(net);
out_state:
xfrm_statistics_fini(net);
out_statistics:
return rv;
}
static void __net_exit xfrm_net_exit(struct net *net)
{
xfrm_nat_keepalive_net_fini(net);
xfrm_sysctl_fini(net);
xfrm_policy_fini(net);
xfrm_state_fini(net);
xfrm_statistics_fini(net);
}
static struct pernet_operations __net_initdata xfrm_net_ops = {
.init = xfrm_net_init,
.exit = xfrm_net_exit,
};
static const struct flow_dissector_key xfrm_flow_dissector_keys[] = {
{
.key_id = FLOW_DISSECTOR_KEY_CONTROL,
.offset = offsetof(struct xfrm_flow_keys, control),
},
{
.key_id = FLOW_DISSECTOR_KEY_BASIC,
.offset = offsetof(struct xfrm_flow_keys, basic),
},
{
.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
.offset = offsetof(struct xfrm_flow_keys, addrs.ipv4),
},
{
.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
.offset = offsetof(struct xfrm_flow_keys, addrs.ipv6),
},
{
.key_id = FLOW_DISSECTOR_KEY_PORTS,
.offset = offsetof(struct xfrm_flow_keys, ports),
},
{
.key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
.offset = offsetof(struct xfrm_flow_keys, gre),
},
{
.key_id = FLOW_DISSECTOR_KEY_IP,
.offset = offsetof(struct xfrm_flow_keys, ip),
},
{
.key_id = FLOW_DISSECTOR_KEY_ICMP,
.offset = offsetof(struct xfrm_flow_keys, icmp),
},
};
void __init xfrm_init(void)
{
skb_flow_dissector_init(&xfrm_session_dissector,
xfrm_flow_dissector_keys,
ARRAY_SIZE(xfrm_flow_dissector_keys));
register_pernet_subsys(&xfrm_net_ops);
xfrm_dev_init();
xfrm_input_init();
#ifdef CONFIG_XFRM_ESPINTCP
espintcp_init();
#endif
register_xfrm_state_bpf();
xfrm_nat_keepalive_init(AF_INET);
}
#ifdef CONFIG_AUDITSYSCALL
static void xfrm_audit_common_policyinfo(struct xfrm_policy *xp,
struct audit_buffer *audit_buf)
{
struct xfrm_sec_ctx *ctx = xp->security;
struct xfrm_selector *sel = &xp->selector;
if (ctx)
audit_log_format(audit_buf, " sec_alg=%u sec_doi=%u sec_obj=%s",
ctx->ctx_alg, ctx->ctx_doi, ctx->ctx_str);
switch (sel->family) {
case AF_INET:
audit_log_format(audit_buf, " src=%pI4", &sel->saddr.a4);
if (sel->prefixlen_s != 32)
audit_log_format(audit_buf, " src_prefixlen=%d",
sel->prefixlen_s);
audit_log_format(audit_buf, " dst=%pI4", &sel->daddr.a4);
if (sel->prefixlen_d != 32)
audit_log_format(audit_buf, " dst_prefixlen=%d",
sel->prefixlen_d);
break;
case AF_INET6:
audit_log_format(audit_buf, " src=%pI6", sel->saddr.a6);
if (sel->prefixlen_s != 128)
audit_log_format(audit_buf, " src_prefixlen=%d",
sel->prefixlen_s);
audit_log_format(audit_buf, " dst=%pI6", sel->daddr.a6);
if (sel->prefixlen_d != 128)
audit_log_format(audit_buf, " dst_prefixlen=%d",
sel->prefixlen_d);
break;
}
}
void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
{
struct audit_buffer *audit_buf;
audit_buf = xfrm_audit_start("SPD-add");
if (audit_buf == NULL)
return;
xfrm_audit_helper_usrinfo(task_valid, audit_buf);
audit_log_format(audit_buf, " res=%u", result);
xfrm_audit_common_policyinfo(xp, audit_buf);
audit_log_end(audit_buf);
}
EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
bool task_valid)
{
struct audit_buffer *audit_buf;
audit_buf = xfrm_audit_start("SPD-delete");
if (audit_buf == NULL)
return;
xfrm_audit_helper_usrinfo(task_valid, audit_buf);
audit_log_format(audit_buf, " res=%u", result);
xfrm_audit_common_policyinfo(xp, audit_buf);
audit_log_end(audit_buf);
}
EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
#endif
#ifdef CONFIG_XFRM_MIGRATE
static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *sel,
u8 dir, u8 type, struct net *net, u32 if_id)
{
struct xfrm_policy *pol;
struct flowi fl;
memset(&fl, 0, sizeof(fl));
fl.flowi_proto = sel->proto;
switch (sel->family) {
case AF_INET:
fl.u.ip4.saddr = sel->saddr.a4;
fl.u.ip4.daddr = sel->daddr.a4;
if (sel->proto == IPSEC_ULPROTO_ANY)
break;
fl.u.flowi4_oif = sel->ifindex;
fl.u.ip4.fl4_sport = sel->sport;
fl.u.ip4.fl4_dport = sel->dport;
break;
case AF_INET6:
fl.u.ip6.saddr = sel->saddr.in6;
fl.u.ip6.daddr = sel->daddr.in6;
if (sel->proto == IPSEC_ULPROTO_ANY)
break;
fl.u.flowi6_oif = sel->ifindex;
fl.u.ip6.fl4_sport = sel->sport;
fl.u.ip6.fl4_dport = sel->dport;
break;
default:
return ERR_PTR(-EAFNOSUPPORT);
}
rcu_read_lock();
pol = xfrm_policy_lookup_bytype(net, type, &fl, sel->family, dir, if_id);
if (IS_ERR_OR_NULL(pol))
goto out_unlock;
if (!xfrm_pol_hold_rcu(pol))
pol = NULL;
out_unlock:
rcu_read_unlock();
return pol;
}
static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
{
int match = 0;
if (t->mode == m->mode && t->id.proto == m->proto &&
(m->reqid == 0 || t->reqid == m->reqid)) {
switch (t->mode) {
case XFRM_MODE_TUNNEL:
case XFRM_MODE_BEET:
if (xfrm_addr_equal(&t->id.daddr, &m->old_daddr,
m->old_family) &&
xfrm_addr_equal(&t->saddr, &m->old_saddr,
m->old_family)) {
match = 1;
}
break;
case XFRM_MODE_TRANSPORT:
/* in case of transport mode, template does not store
any IP addresses, hence we just compare mode and
protocol */
match = 1;
break;
default:
break;
}
}
return match;
}
/* update endpoint address(es) of template(s) */
static int xfrm_policy_migrate(struct xfrm_policy *pol,
struct xfrm_migrate *m, int num_migrate,
struct netlink_ext_ack *extack)
{
struct xfrm_migrate *mp;
int i, j, n = 0;
write_lock_bh(&pol->lock);
if (unlikely(pol->walk.dead)) {
/* target policy has been deleted */
NL_SET_ERR_MSG(extack, "Target policy not found");
write_unlock_bh(&pol->lock);
return -ENOENT;
}
for (i = 0; i < pol->xfrm_nr; i++) {
for (j = 0, mp = m; j < num_migrate; j++, mp++) {
if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i]))
continue;
n++;
if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL &&
pol->xfrm_vec[i].mode != XFRM_MODE_BEET)
continue;
/* update endpoints */
memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr,
sizeof(pol->xfrm_vec[i].id.daddr));
memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr,
sizeof(pol->xfrm_vec[i].saddr));
pol->xfrm_vec[i].encap_family = mp->new_family;
/* flush bundles */
atomic_inc(&pol->genid);
}
}
write_unlock_bh(&pol->lock);
if (!n)
return -ENODATA;
return 0;
}
static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate,
struct netlink_ext_ack *extack)
{
int i, j;
if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) {
NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)");
return -EINVAL;
}
for (i = 0; i < num_migrate; i++) {
if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) ||
xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) {
NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null");
return -EINVAL;
}
/* check if there is any duplicated entry */
for (j = i + 1; j < num_migrate; j++) {
if (!memcmp(&m[i].old_daddr, &m[j].old_daddr,
sizeof(m[i].old_daddr)) &&
!memcmp(&m[i].old_saddr, &m[j].old_saddr,
sizeof(m[i].old_saddr)) &&
m[i].proto == m[j].proto &&
m[i].mode == m[j].mode &&
m[i].reqid == m[j].reqid &&
m[i].old_family == m[j].old_family) {
NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique");
return -EINVAL;
}
}
}
return 0;
}
int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
struct xfrm_migrate *m, int num_migrate,
struct xfrm_kmaddress *k, struct net *net,
struct xfrm_encap_tmpl *encap, u32 if_id,
struct netlink_ext_ack *extack)
{
int i, err, nx_cur = 0, nx_new = 0;
struct xfrm_policy *pol = NULL;
struct xfrm_state *x, *xc;
struct xfrm_state *x_cur[XFRM_MAX_DEPTH];
struct xfrm_state *x_new[XFRM_MAX_DEPTH];
struct xfrm_migrate *mp;
/* Stage 0 - sanity checks */
err = xfrm_migrate_check(m, num_migrate, extack);
if (err < 0)
goto out;
if (dir >= XFRM_POLICY_MAX) {
NL_SET_ERR_MSG(extack, "Invalid policy direction");
err = -EINVAL;
goto out;
}
/* Stage 1 - find policy */
pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id);
if (IS_ERR_OR_NULL(pol)) {
NL_SET_ERR_MSG(extack, "Target policy not found");
err = IS_ERR(pol) ? PTR_ERR(pol) : -ENOENT;
goto out;
}
/* Stage 2 - find and update state(s) */
for (i = 0, mp = m; i < num_migrate; i++, mp++) {
if ((x = xfrm_migrate_state_find(mp, net, if_id))) {
x_cur[nx_cur] = x;
nx_cur++;
xc = xfrm_state_migrate(x, mp, encap);
if (xc) {
x_new[nx_new] = xc;
nx_new++;
} else {
err = -ENODATA;
goto restore_state;
}
}
}
/* Stage 3 - update policy */
err = xfrm_policy_migrate(pol, m, num_migrate, extack);
if (err < 0)
goto restore_state;
/* Stage 4 - delete old state(s) */
if (nx_cur) {
xfrm_states_put(x_cur, nx_cur);
xfrm_states_delete(x_cur, nx_cur);
}
/* Stage 5 - announce */
km_migrate(sel, dir, type, m, num_migrate, k, encap);
xfrm_pol_put(pol);
return 0;
out:
return err;
restore_state:
if (pol)
xfrm_pol_put(pol);
if (nx_cur)
xfrm_states_put(x_cur, nx_cur);
if (nx_new)
xfrm_states_delete(x_new, nx_new);
return err;
}
EXPORT_SYMBOL(xfrm_migrate);
#endif
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