diff options
Diffstat (limited to '')
| -rw-r--r-- | net/xfrm/xfrm_policy.c | 4490 |
1 files changed, 4490 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c new file mode 100644 index 000000000..e47c670c7 --- /dev/null +++ b/net/xfrm/xfrm_policy.c @@ -0,0 +1,4490 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * xfrm_policy.c + * + * Changes: + * Mitsuru KANDA @USAGI + * Kazunori MIYAZAWA @USAGI + * Kunihiro Ishiguro <kunihiro@ipinfusion.com> + * IPv6 support + * Kazunori MIYAZAWA @USAGI + * YOSHIFUJI Hideaki + * Split up af-specific portion + * Derek Atkins <derek@ihtfp.com> 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 <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 "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 results have same prio, youngest one wins. + */ + +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]; +}; + +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 void xfrm_policy_insert_inexact_list(struct hlist_head *chain, + struct xfrm_policy *policy); + +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_inexact_list); + 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(); + + 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) +{ + 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) { + 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, int total) +{ + 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, total); + + 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) + 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); + } + + chain = &net->xfrm.policy_inexact[dir]; + xfrm_policy_insert_inexact_list(chain, policy); + + if (delpol) + __xfrm_policy_inexact_prune_bin(bin, false); + + return delpol; +} + +static void xfrm_hash_rebuild(struct work_struct *work) +{ + struct net *net = container_of(work, struct net, + xfrm.policy_hthresh.work); + unsigned int hmask; + struct xfrm_policy *pol; + struct xfrm_policy *policy; + struct hlist_head *chain; + struct hlist_head *odst; + struct hlist_node *newpos; + int i; + 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 (policy->walk.dead) + continue; + + dir = xfrm_policy_id2dir(policy->index); + if (dir >= XFRM_POLICY_MAX) + continue; + + 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; + } + + /* reset the bydst and inexact table in all directions */ + for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { + struct hlist_node *n; + + hlist_for_each_entry_safe(policy, n, + &net->xfrm.policy_inexact[dir], + bydst_inexact_list) { + hlist_del_rcu(&policy->bydst); + hlist_del_init(&policy->bydst_inexact_list); + } + + hmask = net->xfrm.policy_bydst[dir].hmask; + odst = net->xfrm.policy_bydst[dir].table; + for (i = hmask; i >= 0; i--) { + hlist_for_each_entry_safe(policy, n, odst + i, bydst) + hlist_del_rcu(&policy->bydst); + } + 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 (policy->walk.dead) + continue; + dir = xfrm_policy_id2dir(policy->index); + if (dir >= XFRM_POLICY_MAX) { + /* skip socket policies */ + continue; + } + newpos = NULL; + 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) + 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 void xfrm_policy_insert_inexact_list(struct hlist_head *chain, + struct xfrm_policy *policy) +{ + struct xfrm_policy *pol, *delpol = NULL; + struct hlist_node *newpos = NULL; + int i = 0; + + hlist_for_each_entry(pol, chain, bydst_inexact_list) { + 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)) { + delpol = pol; + if (policy->priority > pol->priority) + continue; + } else if (policy->priority >= pol->priority) { + newpos = &pol->bydst_inexact_list; + continue; + } + if (delpol) + break; + } + + if (newpos) + hlist_add_behind_rcu(&policy->bydst_inexact_list, newpos); + else + hlist_add_head_rcu(&policy->bydst_inexact_list, chain); + + hlist_for_each_entry(pol, chain, bydst_inexact_list) { + pol->pos = i; + i++; + } +} + +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) + hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); + else + 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; +} +#else +static inline int +xfrm_policy_flush_secctx_check(struct net *net, u8 type, 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_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; + } + } + 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 void __xfrm_policy_link(struct xfrm_policy *pol, int dir) +{ + struct net *net = xp_net(pol); + + 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_init(&pol->bydst_inexact_list); + 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->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 IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; + + 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, 1, 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) { + struct rt6_info *rt = (struct rt6_info *)dst; + path->path_cookie = rt6_get_cookie(rt); + 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]); + + 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(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(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(struct sk_buff *skb, struct flowi *fl, bool reverse) +{ + const struct iphdr *iph = ip_hdr(skb); + int ihl = iph->ihl; + u8 *xprth = skb_network_header(skb) + ihl * 4; + struct flowi4 *fl4 = &fl->u.ip4; + int oif = 0; + + if (skb_dst(skb) && skb_dst(skb)->dev) + oif = skb_dst(skb)->dev->ifindex; + + memset(fl4, 0, sizeof(struct flowi4)); + fl4->flowi4_mark = skb->mark; + fl4->flowi4_oif = reverse ? skb->skb_iif : oif; + + fl4->flowi4_proto = iph->protocol; + fl4->daddr = reverse ? iph->saddr : iph->daddr; + fl4->saddr = reverse ? iph->daddr : iph->saddr; + fl4->flowi4_tos = iph->tos & ~INET_ECN_MASK; + + if (!ip_is_fragment(iph)) { + switch (iph->protocol) { + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + case IPPROTO_TCP: + case IPPROTO_SCTP: + case IPPROTO_DCCP: + if (xprth + 4 < skb->data || + pskb_may_pull(skb, xprth + 4 - skb->data)) { + __be16 *ports; + + xprth = skb_network_header(skb) + ihl * 4; + ports = (__be16 *)xprth; + + fl4->fl4_sport = ports[!!reverse]; + fl4->fl4_dport = ports[!reverse]; + } + break; + case IPPROTO_ICMP: + if (xprth + 2 < skb->data || + pskb_may_pull(skb, xprth + 2 - skb->data)) { + u8 *icmp; + + xprth = skb_network_header(skb) + ihl * 4; + icmp = xprth; + + fl4->fl4_icmp_type = icmp[0]; + fl4->fl4_icmp_code = icmp[1]; + } + break; + case IPPROTO_GRE: + if (xprth + 12 < skb->data || + pskb_may_pull(skb, xprth + 12 - skb->data)) { + __be16 *greflags; + __be32 *gre_hdr; + + xprth = skb_network_header(skb) + ihl * 4; + greflags = (__be16 *)xprth; + gre_hdr = (__be32 *)xprth; + + if (greflags[0] & GRE_KEY) { + if (greflags[0] & GRE_CSUM) + gre_hdr++; + fl4->fl4_gre_key = gre_hdr[1]; + } + } + break; + default: + break; + } + } +} + +#if IS_ENABLED(CONFIG_IPV6) +static void +decode_session6(struct sk_buff *skb, struct flowi *fl, bool reverse) +{ + struct flowi6 *fl6 = &fl->u.ip6; + int onlyproto = 0; + const struct ipv6hdr *hdr = ipv6_hdr(skb); + u32 offset = sizeof(*hdr); + struct ipv6_opt_hdr *exthdr; + const unsigned char *nh = skb_network_header(skb); + u16 nhoff = IP6CB(skb)->nhoff; + int oif = 0; + u8 nexthdr; + + if (!nhoff) + nhoff = offsetof(struct ipv6hdr, nexthdr); + + nexthdr = nh[nhoff]; + + if (skb_dst(skb) && skb_dst(skb)->dev) + oif = skb_dst(skb)->dev->ifindex; + + memset(fl6, 0, sizeof(struct flowi6)); + fl6->flowi6_mark = skb->mark; + fl6->flowi6_oif = reverse ? skb->skb_iif : oif; + + fl6->daddr = reverse ? hdr->saddr : hdr->daddr; + fl6->saddr = reverse ? hdr->daddr : hdr->saddr; + + while (nh + offset + sizeof(*exthdr) < skb->data || + pskb_may_pull(skb, nh + offset + sizeof(*exthdr) - skb->data)) { + nh = skb_network_header(skb); + exthdr = (struct ipv6_opt_hdr *)(nh + offset); + + switch (nexthdr) { + case NEXTHDR_FRAGMENT: + onlyproto = 1; + fallthrough; + case NEXTHDR_ROUTING: + case NEXTHDR_HOP: + case NEXTHDR_DEST: + offset += ipv6_optlen(exthdr); + nexthdr = exthdr->nexthdr; + break; + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + case IPPROTO_TCP: + case IPPROTO_SCTP: + case IPPROTO_DCCP: + if (!onlyproto && (nh + offset + 4 < skb->data || + pskb_may_pull(skb, nh + offset + 4 - skb->data))) { + __be16 *ports; + + nh = skb_network_header(skb); + ports = (__be16 *)(nh + offset); + fl6->fl6_sport = ports[!!reverse]; + fl6->fl6_dport = ports[!reverse]; + } + fl6->flowi6_proto = nexthdr; + return; + case IPPROTO_ICMPV6: + if (!onlyproto && (nh + offset + 2 < skb->data || + pskb_may_pull(skb, nh + offset + 2 - skb->data))) { + u8 *icmp; + + nh = skb_network_header(skb); + icmp = (u8 *)(nh + offset); + fl6->fl6_icmp_type = icmp[0]; + fl6->fl6_icmp_code = icmp[1]; + } + fl6->flowi6_proto = nexthdr; + return; + case IPPROTO_GRE: + if (!onlyproto && + (nh + offset + 12 < skb->data || + pskb_may_pull(skb, nh + offset + 12 - skb->data))) { + struct gre_base_hdr *gre_hdr; + __be32 *gre_key; + + nh = skb_network_header(skb); + gre_hdr = (struct gre_base_hdr *)(nh + offset); + gre_key = (__be32 *)(gre_hdr + 1); + + if (gre_hdr->flags & GRE_KEY) { + if (gre_hdr->flags & GRE_CSUM) + gre_key++; + fl6->fl6_gre_key = *gre_key; + } + } + fl6->flowi6_proto = nexthdr; + return; + +#if IS_ENABLED(CONFIG_IPV6_MIP6) + case IPPROTO_MH: + offset += ipv6_optlen(exthdr); + if (!onlyproto && (nh + offset + 3 < skb->data || + pskb_may_pull(skb, nh + offset + 3 - skb->data))) { + struct ip6_mh *mh; + + nh = skb_network_header(skb); + mh = (struct ip6_mh *)(nh + offset); + fl6->fl6_mh_type = mh->ip6mh_type; + } + fl6->flowi6_proto = nexthdr; + return; +#endif + default: + fl6->flowi6_proto = nexthdr; + return; + } + } +} +#endif + +int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, + unsigned int family, int reverse) +{ + switch (family) { + case AF_INET: + decode_session4(skb, fl, reverse); + break; +#if IS_ENABLED(CONFIG_IPV6) + case AF_INET6: + decode_session6(skb, fl, reverse); + break; +#endif + default: + return -EAFNOSUPPORT; + } + + 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; +} + +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(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]; + if (!xfrm_selector_match(&x->sel, &fl, family)) { + 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) { + 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)) { + 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(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; + } + 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 struct dst_entry *xfrm_negative_advice(struct dst_entry *dst) +{ + if (dst) { + if (dst->obsolete) { + dst_release(dst); + dst = NULL; + } + } + return dst; +} + +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_create("xfrm_dst_cache", + sizeof(struct xfrm_dst), + 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, + NULL); + 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; + + return 0; + +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_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, +}; + +void __init xfrm_init(void) +{ + register_pernet_subsys(&xfrm_net_ops); + xfrm_dev_init(); + xfrm_input_init(); + +#ifdef CONFIG_XFRM_ESPINTCP + espintcp_init(); +#endif +} + +#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 bool xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp, + const struct xfrm_selector *sel_tgt) +{ + if (sel_cmp->proto == IPSEC_ULPROTO_ANY) { + if (sel_tgt->family == sel_cmp->family && + xfrm_addr_equal(&sel_tgt->daddr, &sel_cmp->daddr, + sel_cmp->family) && + xfrm_addr_equal(&sel_tgt->saddr, &sel_cmp->saddr, + sel_cmp->family) && + sel_tgt->prefixlen_d == sel_cmp->prefixlen_d && + sel_tgt->prefixlen_s == sel_cmp->prefixlen_s) { + return true; + } + } else { + if (memcmp(sel_tgt, sel_cmp, sizeof(*sel_tgt)) == 0) { + return true; + } + } + return false; +} + +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, *ret = NULL; + struct hlist_head *chain; + u32 priority = ~0U; + + spin_lock_bh(&net->xfrm.xfrm_policy_lock); + chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir); + hlist_for_each_entry(pol, chain, bydst) { + if ((if_id == 0 || pol->if_id == if_id) && + xfrm_migrate_selector_match(sel, &pol->selector) && + pol->type == type) { + ret = pol; + priority = ret->priority; + break; + } + } + chain = &net->xfrm.policy_inexact[dir]; + hlist_for_each_entry(pol, chain, bydst_inexact_list) { + if ((pol->priority >= priority) && ret) + break; + + if ((if_id == 0 || pol->if_id == if_id) && + xfrm_migrate_selector_match(sel, &pol->selector) && + pol->type == type) { + ret = pol; + break; + } + } + + xfrm_pol_hold(ret); + + spin_unlock_bh(&net->xfrm.xfrm_policy_lock); + + return ret; +} + +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 xfrm_migrate *mp; + int i, j, n = 0; + + write_lock_bh(&pol->lock); + if (unlikely(pol->walk.dead)) { + /* target policy has been deleted */ + 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) +{ + int i, j; + + if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) + 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)) + 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) + 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) +{ + 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 */ + if ((err = xfrm_migrate_check(m, num_migrate)) < 0) + goto out; + + if (dir >= XFRM_POLICY_MAX) { + err = -EINVAL; + goto out; + } + + /* Stage 1 - find policy */ + if ((pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id)) == NULL) { + err = -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 */ + if ((err = xfrm_policy_migrate(pol, m, num_migrate)) < 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 |