// SPDX-License-Identifier: GPL-2.0-only /* * xfrm_policy.c * * Changes: * Mitsuru KANDA @USAGI * Kazunori MIYAZAWA @USAGI * Kunihiro Ishiguro * IPv6 support * Kazunori MIYAZAWA @USAGI * YOSHIFUJI Hideaki * Split up af-specific portion * Derek Atkins Add the post_input processor * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #if IS_ENABLED(CONFIG_IPV6_MIP6) #include #endif #ifdef CONFIG_XFRM_STATISTICS #include #endif #ifdef CONFIG_XFRM_ESPINTCP #include #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]; }; struct xfrm_flow_keys { struct flow_dissector_key_basic basic; struct flow_dissector_key_control control; union { struct flow_dissector_key_ipv4_addrs ipv4; struct flow_dissector_key_ipv6_addrs ipv6; } addrs; struct flow_dissector_key_ip ip; struct flow_dissector_key_icmp icmp; struct flow_dissector_key_ports ports; struct flow_dissector_key_keyid gre; }; static struct flow_dissector xfrm_session_dissector __ro_after_init; static DEFINE_SPINLOCK(xfrm_if_cb_lock); static struct xfrm_if_cb const __rcu *xfrm_if_cb __read_mostly; static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock); static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] __read_mostly; static struct kmem_cache *xfrm_dst_cache __ro_after_init; static struct rhashtable xfrm_policy_inexact_table; static const struct rhashtable_params xfrm_pol_inexact_params; static void xfrm_init_pmtu(struct xfrm_dst **bundle, int nr); static int stale_bundle(struct dst_entry *dst); static int xfrm_bundle_ok(struct xfrm_dst *xdst); static void xfrm_policy_queue_process(struct timer_list *t); static void __xfrm_policy_link(struct xfrm_policy *pol, int dir); static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, int dir); static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, u32 if_id); static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, u8 dir, u32 if_id); static struct xfrm_policy * xfrm_policy_insert_list(struct hlist_head *chain, struct xfrm_policy *policy, bool excl); static 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(); xfrm_dev_policy_free(policy); call_rcu(&policy->rcu, xfrm_policy_destroy_rcu); } EXPORT_SYMBOL(xfrm_policy_destroy); /* Rule must be locked. Release descendant resources, announce * entry dead. The rule must be unlinked from lists to the moment. */ static void xfrm_policy_kill(struct xfrm_policy *policy) { write_lock_bh(&policy->lock); policy->walk.dead = 1; write_unlock_bh(&policy->lock); atomic_inc(&policy->genid); if (del_timer(&policy->polq.hold_timer)) xfrm_pol_put(policy); skb_queue_purge(&policy->polq.hold_queue); if (del_timer(&policy->timer)) xfrm_pol_put(policy); xfrm_pol_put(policy); } static unsigned int xfrm_policy_hashmax __read_mostly = 1 * 1024 * 1024; static inline unsigned int idx_hash(struct net *net, u32 index) { return __idx_hash(index, net->xfrm.policy_idx_hmask); } /* calculate policy hash thresholds */ static void __get_hash_thresh(struct net *net, unsigned short family, int dir, u8 *dbits, u8 *sbits) { switch (family) { case AF_INET: *dbits = net->xfrm.policy_bydst[dir].dbits4; *sbits = net->xfrm.policy_bydst[dir].sbits4; break; case AF_INET6: *dbits = net->xfrm.policy_bydst[dir].dbits6; *sbits = net->xfrm.policy_bydst[dir].sbits6; break; default: *dbits = 0; *sbits = 0; } } static struct hlist_head *policy_hash_bysel(struct net *net, const struct xfrm_selector *sel, unsigned short family, int dir) { unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; unsigned int hash; u8 dbits; u8 sbits; __get_hash_thresh(net, family, dir, &dbits, &sbits); hash = __sel_hash(sel, family, hmask, dbits, sbits); if (hash == hmask + 1) return NULL; return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; } static struct hlist_head *policy_hash_direct(struct net *net, const xfrm_address_t *daddr, const xfrm_address_t *saddr, unsigned short family, int dir) { unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; unsigned int hash; u8 dbits; u8 sbits; __get_hash_thresh(net, family, dir, &dbits, &sbits); hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits); return rcu_dereference_check(net->xfrm.policy_bydst[dir].table, lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash; } static void xfrm_dst_hash_transfer(struct net *net, struct hlist_head *list, struct hlist_head *ndsttable, unsigned int nhashmask, int dir) { struct hlist_node *tmp, *entry0 = NULL; struct xfrm_policy *pol; unsigned int h0 = 0; u8 dbits; u8 sbits; redo: hlist_for_each_entry_safe(pol, tmp, list, bydst) { unsigned int h; __get_hash_thresh(net, pol->family, dir, &dbits, &sbits); h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr, pol->family, nhashmask, dbits, sbits); if (!entry0 || pol->xdo.type == XFRM_DEV_OFFLOAD_PACKET) { hlist_del_rcu(&pol->bydst); hlist_add_head_rcu(&pol->bydst, ndsttable + h); h0 = h; } else { if (h != h0) continue; hlist_del_rcu(&pol->bydst); hlist_add_behind_rcu(&pol->bydst, entry0); } entry0 = &pol->bydst; } if (!hlist_empty(list)) { entry0 = NULL; goto redo; } } static void xfrm_idx_hash_transfer(struct hlist_head *list, struct hlist_head *nidxtable, unsigned int nhashmask) { struct hlist_node *tmp; struct xfrm_policy *pol; hlist_for_each_entry_safe(pol, tmp, list, byidx) { unsigned int h; h = __idx_hash(pol->index, nhashmask); hlist_add_head(&pol->byidx, nidxtable+h); } } static unsigned long xfrm_new_hash_mask(unsigned int old_hmask) { return ((old_hmask + 1) << 1) - 1; } static void xfrm_bydst_resize(struct net *net, int dir) { unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; unsigned int nhashmask = xfrm_new_hash_mask(hmask); unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); struct hlist_head *ndst = xfrm_hash_alloc(nsize); struct hlist_head *odst; int i; if (!ndst) return; spin_lock_bh(&net->xfrm.xfrm_policy_lock); write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, lockdep_is_held(&net->xfrm.xfrm_policy_lock)); for (i = hmask; i >= 0; i--) xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir); rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); net->xfrm.policy_bydst[dir].hmask = nhashmask; write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); synchronize_rcu(); xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head)); } static void xfrm_byidx_resize(struct net *net) { unsigned int hmask = net->xfrm.policy_idx_hmask; unsigned int nhashmask = xfrm_new_hash_mask(hmask); unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head); struct hlist_head *oidx = net->xfrm.policy_byidx; struct hlist_head *nidx = xfrm_hash_alloc(nsize); int i; if (!nidx) return; spin_lock_bh(&net->xfrm.xfrm_policy_lock); for (i = hmask; i >= 0; i--) xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask); net->xfrm.policy_byidx = nidx; net->xfrm.policy_idx_hmask = nhashmask; spin_unlock_bh(&net->xfrm.xfrm_policy_lock); xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head)); } static inline int xfrm_bydst_should_resize(struct net *net, int dir, int *total) { unsigned int cnt = net->xfrm.policy_count[dir]; unsigned int hmask = net->xfrm.policy_bydst[dir].hmask; if (total) *total += cnt; if ((hmask + 1) < xfrm_policy_hashmax && cnt > hmask) return 1; return 0; } static inline int xfrm_byidx_should_resize(struct net *net, int total) { unsigned int hmask = net->xfrm.policy_idx_hmask; if ((hmask + 1) < xfrm_policy_hashmax && total > hmask) return 1; return 0; } void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si) { si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN]; si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT]; si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD]; si->inscnt = net->xfrm.policy_count[XFRM_POLICY_IN+XFRM_POLICY_MAX]; si->outscnt = net->xfrm.policy_count[XFRM_POLICY_OUT+XFRM_POLICY_MAX]; si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX]; si->spdhcnt = net->xfrm.policy_idx_hmask; si->spdhmcnt = xfrm_policy_hashmax; } EXPORT_SYMBOL(xfrm_spd_getinfo); static DEFINE_MUTEX(hash_resize_mutex); static void xfrm_hash_resize(struct work_struct *work) { struct net *net = container_of(work, struct net, xfrm.policy_hash_work); int dir, total; mutex_lock(&hash_resize_mutex); total = 0; for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { if (xfrm_bydst_should_resize(net, dir, &total)) xfrm_bydst_resize(net, dir); } if (xfrm_byidx_should_resize(net, total)) xfrm_byidx_resize(net); mutex_unlock(&hash_resize_mutex); } /* Make sure *pol can be inserted into fastbin. * Useful to check that later insert requests will be successful * (provided xfrm_policy_lock is held throughout). */ static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) { struct xfrm_pol_inexact_bin *bin, *prev; struct xfrm_pol_inexact_key k = { .family = pol->family, .type = pol->type, .dir = dir, .if_id = pol->if_id, }; struct net *net = xp_net(pol); lockdep_assert_held(&net->xfrm.xfrm_policy_lock); write_pnet(&k.net, net); bin = rhashtable_lookup_fast(&xfrm_policy_inexact_table, &k, xfrm_pol_inexact_params); if (bin) return bin; bin = kzalloc(sizeof(*bin), GFP_ATOMIC); if (!bin) return NULL; bin->k = k; INIT_HLIST_HEAD(&bin->hhead); bin->root_d = RB_ROOT; bin->root_s = RB_ROOT; seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, &bin->k, &bin->head, xfrm_pol_inexact_params); if (!prev) { list_add(&bin->inexact_bins, &net->xfrm.inexact_bins); return bin; } kfree(bin); return IS_ERR(prev) ? NULL : prev; } static bool xfrm_pol_inexact_addr_use_any_list(const xfrm_address_t *addr, int family, u8 prefixlen) { if (xfrm_addr_any(addr, family)) return true; if (family == AF_INET6 && prefixlen < INEXACT_PREFIXLEN_IPV6) return true; if (family == AF_INET && prefixlen < INEXACT_PREFIXLEN_IPV4) return true; return false; } static bool xfrm_policy_inexact_insert_use_any_list(const struct xfrm_policy *policy) { const xfrm_address_t *addr; bool saddr_any, daddr_any; u8 prefixlen; addr = &policy->selector.saddr; prefixlen = policy->selector.prefixlen_s; saddr_any = xfrm_pol_inexact_addr_use_any_list(addr, policy->family, prefixlen); addr = &policy->selector.daddr; prefixlen = policy->selector.prefixlen_d; daddr_any = xfrm_pol_inexact_addr_use_any_list(addr, policy->family, prefixlen); return saddr_any && daddr_any; } static void xfrm_pol_inexact_node_init(struct xfrm_pol_inexact_node *node, const xfrm_address_t *addr, u8 prefixlen) { node->addr = *addr; node->prefixlen = prefixlen; } static struct xfrm_pol_inexact_node * xfrm_pol_inexact_node_alloc(const xfrm_address_t *addr, u8 prefixlen) { struct xfrm_pol_inexact_node *node; node = kzalloc(sizeof(*node), GFP_ATOMIC); if (node) xfrm_pol_inexact_node_init(node, addr, prefixlen); return node; } static int xfrm_policy_addr_delta(const xfrm_address_t *a, const xfrm_address_t *b, u8 prefixlen, u16 family) { u32 ma, mb, mask; unsigned int pdw, pbi; int delta = 0; switch (family) { case AF_INET: if (prefixlen == 0) return 0; mask = ~0U << (32 - prefixlen); ma = ntohl(a->a4) & mask; mb = ntohl(b->a4) & mask; if (ma < mb) delta = -1; else if (ma > mb) delta = 1; break; case AF_INET6: pdw = prefixlen >> 5; pbi = prefixlen & 0x1f; if (pdw) { delta = memcmp(a->a6, b->a6, pdw << 2); if (delta) return delta; } if (pbi) { mask = ~0U << (32 - pbi); ma = ntohl(a->a6[pdw]) & mask; mb = ntohl(b->a6[pdw]) & mask; if (ma < mb) delta = -1; else if (ma > mb) delta = 1; } break; default: break; } return delta; } static void xfrm_policy_inexact_list_reinsert(struct net *net, struct xfrm_pol_inexact_node *n, u16 family) { unsigned int matched_s, matched_d; struct xfrm_policy *policy, *p; matched_s = 0; matched_d = 0; list_for_each_entry_reverse(policy, &net->xfrm.policy_all, walk.all) { struct hlist_node *newpos = NULL; bool matches_s, matches_d; if (policy->walk.dead || !policy->bydst_reinsert) continue; WARN_ON_ONCE(policy->family != family); policy->bydst_reinsert = false; hlist_for_each_entry(p, &n->hhead, bydst) { if (policy->priority > p->priority) newpos = &p->bydst; else if (policy->priority == p->priority && policy->pos > p->pos) newpos = &p->bydst; else break; } if (newpos && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) hlist_add_behind_rcu(&policy->bydst, newpos); else hlist_add_head_rcu(&policy->bydst, &n->hhead); /* paranoia checks follow. * Check that the reinserted policy matches at least * saddr or daddr for current node prefix. * * Matching both is fine, matching saddr in one policy * (but not daddr) and then matching only daddr in another * is a bug. */ matches_s = xfrm_policy_addr_delta(&policy->selector.saddr, &n->addr, n->prefixlen, family) == 0; matches_d = xfrm_policy_addr_delta(&policy->selector.daddr, &n->addr, n->prefixlen, family) == 0; if (matches_s && matches_d) continue; WARN_ON_ONCE(!matches_s && !matches_d); if (matches_s) matched_s++; if (matches_d) matched_d++; WARN_ON_ONCE(matched_s && matched_d); } } static void xfrm_policy_inexact_node_reinsert(struct net *net, struct xfrm_pol_inexact_node *n, struct rb_root *new, u16 family) { struct xfrm_pol_inexact_node *node; struct rb_node **p, *parent; /* we should not have another subtree here */ WARN_ON_ONCE(!RB_EMPTY_ROOT(&n->root)); restart: parent = NULL; p = &new->rb_node; while (*p) { u8 prefixlen; int delta; parent = *p; node = rb_entry(*p, struct xfrm_pol_inexact_node, node); prefixlen = min(node->prefixlen, n->prefixlen); delta = xfrm_policy_addr_delta(&n->addr, &node->addr, prefixlen, family); if (delta < 0) { p = &parent->rb_left; } else if (delta > 0) { p = &parent->rb_right; } else { bool same_prefixlen = node->prefixlen == n->prefixlen; struct xfrm_policy *tmp; hlist_for_each_entry(tmp, &n->hhead, bydst) { tmp->bydst_reinsert = true; hlist_del_rcu(&tmp->bydst); } node->prefixlen = prefixlen; xfrm_policy_inexact_list_reinsert(net, node, family); if (same_prefixlen) { kfree_rcu(n, rcu); return; } rb_erase(*p, new); kfree_rcu(n, rcu); n = node; goto restart; } } rb_link_node_rcu(&n->node, parent, p); rb_insert_color(&n->node, new); } /* merge nodes v and n */ static void xfrm_policy_inexact_node_merge(struct net *net, struct xfrm_pol_inexact_node *v, struct xfrm_pol_inexact_node *n, u16 family) { struct xfrm_pol_inexact_node *node; struct xfrm_policy *tmp; struct rb_node *rnode; /* To-be-merged node v has a subtree. * * Dismantle it and insert its nodes to n->root. */ while ((rnode = rb_first(&v->root)) != NULL) { node = rb_entry(rnode, struct xfrm_pol_inexact_node, node); rb_erase(&node->node, &v->root); xfrm_policy_inexact_node_reinsert(net, node, &n->root, family); } hlist_for_each_entry(tmp, &v->hhead, bydst) { tmp->bydst_reinsert = true; hlist_del_rcu(&tmp->bydst); } xfrm_policy_inexact_list_reinsert(net, n, family); } static struct xfrm_pol_inexact_node * xfrm_policy_inexact_insert_node(struct net *net, struct rb_root *root, xfrm_address_t *addr, u16 family, u8 prefixlen, u8 dir) { struct xfrm_pol_inexact_node *cached = NULL; struct rb_node **p, *parent = NULL; struct xfrm_pol_inexact_node *node; p = &root->rb_node; while (*p) { int delta; parent = *p; node = rb_entry(*p, struct xfrm_pol_inexact_node, node); delta = xfrm_policy_addr_delta(addr, &node->addr, node->prefixlen, family); if (delta == 0 && prefixlen >= node->prefixlen) { WARN_ON_ONCE(cached); /* ipsec policies got lost */ return node; } if (delta < 0) p = &parent->rb_left; else p = &parent->rb_right; if (prefixlen < node->prefixlen) { delta = xfrm_policy_addr_delta(addr, &node->addr, prefixlen, family); if (delta) continue; /* This node is a subnet of the new prefix. It needs * to be removed and re-inserted with the smaller * prefix and all nodes that are now also covered * by the reduced prefixlen. */ rb_erase(&node->node, root); if (!cached) { xfrm_pol_inexact_node_init(node, addr, prefixlen); cached = node; } else { /* This node also falls within the new * prefixlen. Merge the to-be-reinserted * node and this one. */ xfrm_policy_inexact_node_merge(net, node, cached, family); kfree_rcu(node, rcu); } /* restart */ p = &root->rb_node; parent = NULL; } } node = cached; if (!node) { node = xfrm_pol_inexact_node_alloc(addr, prefixlen); if (!node) return NULL; } rb_link_node_rcu(&node->node, parent, p); rb_insert_color(&node->node, root); return node; } static void xfrm_policy_inexact_gc_tree(struct rb_root *r, bool rm) { struct xfrm_pol_inexact_node *node; struct rb_node *rn = rb_first(r); while (rn) { node = rb_entry(rn, struct xfrm_pol_inexact_node, node); xfrm_policy_inexact_gc_tree(&node->root, rm); rn = rb_next(rn); if (!hlist_empty(&node->hhead) || !RB_EMPTY_ROOT(&node->root)) { WARN_ON_ONCE(rm); continue; } rb_erase(&node->node, r); kfree_rcu(node, rcu); } } static void __xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b, bool net_exit) { write_seqcount_begin(&b->count); xfrm_policy_inexact_gc_tree(&b->root_d, net_exit); xfrm_policy_inexact_gc_tree(&b->root_s, net_exit); write_seqcount_end(&b->count); if (!RB_EMPTY_ROOT(&b->root_d) || !RB_EMPTY_ROOT(&b->root_s) || !hlist_empty(&b->hhead)) { WARN_ON_ONCE(net_exit); return; } if (rhashtable_remove_fast(&xfrm_policy_inexact_table, &b->head, xfrm_pol_inexact_params) == 0) { list_del(&b->inexact_bins); kfree_rcu(b, rcu); } } static void xfrm_policy_inexact_prune_bin(struct xfrm_pol_inexact_bin *b) { struct net *net = read_pnet(&b->k.net); spin_lock_bh(&net->xfrm.xfrm_policy_lock); __xfrm_policy_inexact_prune_bin(b, false); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); } static void __xfrm_policy_inexact_flush(struct net *net) { struct xfrm_pol_inexact_bin *bin, *t; lockdep_assert_held(&net->xfrm.xfrm_policy_lock); list_for_each_entry_safe(bin, t, &net->xfrm.inexact_bins, inexact_bins) __xfrm_policy_inexact_prune_bin(bin, false); } static struct hlist_head * xfrm_policy_inexact_alloc_chain(struct xfrm_pol_inexact_bin *bin, struct xfrm_policy *policy, u8 dir) { struct xfrm_pol_inexact_node *n; struct net *net; net = xp_net(policy); lockdep_assert_held(&net->xfrm.xfrm_policy_lock); if (xfrm_policy_inexact_insert_use_any_list(policy)) return &bin->hhead; if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.daddr, policy->family, policy->selector.prefixlen_d)) { write_seqcount_begin(&bin->count); n = xfrm_policy_inexact_insert_node(net, &bin->root_s, &policy->selector.saddr, policy->family, policy->selector.prefixlen_s, dir); write_seqcount_end(&bin->count); if (!n) return NULL; return &n->hhead; } /* daddr is fixed */ write_seqcount_begin(&bin->count); n = xfrm_policy_inexact_insert_node(net, &bin->root_d, &policy->selector.daddr, policy->family, policy->selector.prefixlen_d, dir); write_seqcount_end(&bin->count); if (!n) return NULL; /* saddr is wildcard */ if (xfrm_pol_inexact_addr_use_any_list(&policy->selector.saddr, policy->family, policy->selector.prefixlen_s)) return &n->hhead; write_seqcount_begin(&bin->count); n = xfrm_policy_inexact_insert_node(net, &n->root, &policy->selector.saddr, policy->family, policy->selector.prefixlen_s, dir); write_seqcount_end(&bin->count); if (!n) return NULL; return &n->hhead; } static struct xfrm_policy * xfrm_policy_inexact_insert(struct xfrm_policy *policy, u8 dir, int excl) { struct xfrm_pol_inexact_bin *bin; struct xfrm_policy *delpol; struct hlist_head *chain; struct net *net; bin = xfrm_policy_inexact_alloc_bin(policy, dir); if (!bin) return ERR_PTR(-ENOMEM); net = xp_net(policy); lockdep_assert_held(&net->xfrm.xfrm_policy_lock); chain = xfrm_policy_inexact_alloc_chain(bin, policy, dir); if (!chain) { __xfrm_policy_inexact_prune_bin(bin, false); return ERR_PTR(-ENOMEM); } delpol = xfrm_policy_insert_list(chain, policy, excl); if (delpol && excl) { __xfrm_policy_inexact_prune_bin(bin, false); return ERR_PTR(-EEXIST); } 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 && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) hlist_add_behind_rcu(&policy->bydst, newpos); else hlist_add_head_rcu(&policy->bydst, chain); } out_unlock: __xfrm_policy_inexact_flush(net); write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); mutex_unlock(&hash_resize_mutex); } void xfrm_policy_hash_rebuild(struct net *net) { schedule_work(&net->xfrm.policy_hthresh.work); } EXPORT_SYMBOL(xfrm_policy_hash_rebuild); /* Generate new index... KAME seems to generate them ordered by cost * of an absolute inpredictability of ordering of rules. This will not pass. */ static u32 xfrm_gen_index(struct net *net, int dir, u32 index) { for (;;) { struct hlist_head *list; struct xfrm_policy *p; u32 idx; int found; if (!index) { idx = (net->xfrm.idx_generator | dir); net->xfrm.idx_generator += 8; } else { idx = index; index = 0; } if (idx == 0) idx = 8; list = net->xfrm.policy_byidx + idx_hash(net, idx); found = 0; hlist_for_each_entry(p, list, byidx) { if (p->index == idx) { found = 1; break; } } if (!found) return idx; } } static inline int selector_cmp(struct xfrm_selector *s1, struct xfrm_selector *s2) { u32 *p1 = (u32 *) s1; u32 *p2 = (u32 *) s2; int len = sizeof(struct xfrm_selector) / sizeof(u32); int i; for (i = 0; i < len; i++) { if (p1[i] != p2[i]) return 1; } return 0; } static void xfrm_policy_requeue(struct xfrm_policy *old, struct xfrm_policy *new) { struct xfrm_policy_queue *pq = &old->polq; struct sk_buff_head list; if (skb_queue_empty(&pq->hold_queue)) return; __skb_queue_head_init(&list); spin_lock_bh(&pq->hold_queue.lock); skb_queue_splice_init(&pq->hold_queue, &list); if (del_timer(&pq->hold_timer)) xfrm_pol_put(old); spin_unlock_bh(&pq->hold_queue.lock); pq = &new->polq; spin_lock_bh(&pq->hold_queue.lock); skb_queue_splice(&list, &pq->hold_queue); pq->timeout = XFRM_QUEUE_TMO_MIN; if (!mod_timer(&pq->hold_timer, jiffies)) xfrm_pol_hold(new); spin_unlock_bh(&pq->hold_queue.lock); } static inline bool xfrm_policy_mark_match(const struct xfrm_mark *mark, struct xfrm_policy *pol) { return mark->v == pol->mark.v && mark->m == pol->mark.m; } static u32 xfrm_pol_bin_key(const void *data, u32 len, u32 seed) { const struct xfrm_pol_inexact_key *k = data; u32 a = k->type << 24 | k->dir << 16 | k->family; return jhash_3words(a, k->if_id, net_hash_mix(read_pnet(&k->net)), seed); } static u32 xfrm_pol_bin_obj(const void *data, u32 len, u32 seed) { const struct xfrm_pol_inexact_bin *b = data; return xfrm_pol_bin_key(&b->k, 0, seed); } static int xfrm_pol_bin_cmp(struct rhashtable_compare_arg *arg, const void *ptr) { const struct xfrm_pol_inexact_key *key = arg->key; const struct xfrm_pol_inexact_bin *b = ptr; int ret; if (!net_eq(read_pnet(&b->k.net), read_pnet(&key->net))) return -1; ret = b->k.dir ^ key->dir; if (ret) return ret; ret = b->k.type ^ key->type; if (ret) return ret; ret = b->k.family ^ key->family; if (ret) return ret; return b->k.if_id ^ key->if_id; } static const struct rhashtable_params xfrm_pol_inexact_params = { .head_offset = offsetof(struct xfrm_pol_inexact_bin, head), .hashfn = xfrm_pol_bin_key, .obj_hashfn = xfrm_pol_bin_obj, .obj_cmpfn = xfrm_pol_bin_cmp, .automatic_shrinking = true, }; static 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 && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) 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 && policy->xdo.type != XFRM_DEV_OFFLOAD_PACKET) hlist_add_behind_rcu(&policy->bydst, &newpos->bydst); else /* Packet offload policies enter to the head * to speed-up lookups. */ hlist_add_head_rcu(&policy->bydst, chain); return delpol; } int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) { struct net *net = xp_net(policy); struct xfrm_policy *delpol; struct hlist_head *chain; spin_lock_bh(&net->xfrm.xfrm_policy_lock); chain = policy_hash_bysel(net, &policy->selector, policy->family, dir); if (chain) delpol = xfrm_policy_insert_list(chain, policy, excl); else delpol = xfrm_policy_inexact_insert(policy, dir, excl); if (IS_ERR(delpol)) { spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return PTR_ERR(delpol); } __xfrm_policy_link(policy, dir); /* After previous checking, family can either be AF_INET or AF_INET6 */ if (policy->family == AF_INET) rt_genid_bump_ipv4(net); else rt_genid_bump_ipv6(net); if (delpol) { xfrm_policy_requeue(delpol, policy); __xfrm_policy_unlink(delpol, dir); } policy->index = delpol ? delpol->index : xfrm_gen_index(net, dir, policy->index); hlist_add_head(&policy->byidx, net->xfrm.policy_byidx+idx_hash(net, policy->index)); policy->curlft.add_time = ktime_get_real_seconds(); policy->curlft.use_time = 0; if (!mod_timer(&policy->timer, jiffies + HZ)) xfrm_pol_hold(policy); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); if (delpol) xfrm_policy_kill(delpol); else if (xfrm_bydst_should_resize(net, dir, NULL)) schedule_work(&net->xfrm.policy_hash_work); return 0; } EXPORT_SYMBOL(xfrm_policy_insert); static struct xfrm_policy * __xfrm_policy_bysel_ctx(struct hlist_head *chain, const struct xfrm_mark *mark, u32 if_id, u8 type, int dir, struct xfrm_selector *sel, struct xfrm_sec_ctx *ctx) { struct xfrm_policy *pol; if (!chain) return NULL; hlist_for_each_entry(pol, chain, bydst) { if (pol->type == type && pol->if_id == if_id && xfrm_policy_mark_match(mark, pol) && !selector_cmp(sel, &pol->selector) && xfrm_sec_ctx_match(ctx, pol->security)) return pol; } return NULL; } struct xfrm_policy * xfrm_policy_bysel_ctx(struct net *net, const struct xfrm_mark *mark, u32 if_id, u8 type, int dir, struct xfrm_selector *sel, struct xfrm_sec_ctx *ctx, int delete, int *err) { struct xfrm_pol_inexact_bin *bin = NULL; struct xfrm_policy *pol, *ret = NULL; struct hlist_head *chain; *err = 0; spin_lock_bh(&net->xfrm.xfrm_policy_lock); chain = policy_hash_bysel(net, sel, sel->family, dir); if (!chain) { struct xfrm_pol_inexact_candidates cand; int i; bin = xfrm_policy_inexact_lookup(net, type, sel->family, dir, if_id); if (!bin) { spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return NULL; } if (!xfrm_policy_find_inexact_candidates(&cand, bin, &sel->saddr, &sel->daddr)) { spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return NULL; } pol = NULL; for (i = 0; i < ARRAY_SIZE(cand.res); i++) { struct xfrm_policy *tmp; tmp = __xfrm_policy_bysel_ctx(cand.res[i], mark, if_id, type, dir, sel, ctx); if (!tmp) continue; if (!pol || tmp->pos < pol->pos) pol = tmp; } } else { pol = __xfrm_policy_bysel_ctx(chain, mark, if_id, type, dir, sel, ctx); } if (pol) { xfrm_pol_hold(pol); if (delete) { *err = security_xfrm_policy_delete(pol->security); if (*err) { spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return pol; } __xfrm_policy_unlink(pol, dir); } ret = pol; } spin_unlock_bh(&net->xfrm.xfrm_policy_lock); if (ret && delete) xfrm_policy_kill(ret); if (bin && delete) xfrm_policy_inexact_prune_bin(bin); return ret; } EXPORT_SYMBOL(xfrm_policy_bysel_ctx); struct xfrm_policy * xfrm_policy_byid(struct net *net, const struct xfrm_mark *mark, u32 if_id, u8 type, int dir, u32 id, int delete, int *err) { struct xfrm_policy *pol, *ret; struct hlist_head *chain; *err = -ENOENT; if (xfrm_policy_id2dir(id) != dir) return NULL; *err = 0; spin_lock_bh(&net->xfrm.xfrm_policy_lock); chain = net->xfrm.policy_byidx + idx_hash(net, id); ret = NULL; hlist_for_each_entry(pol, chain, byidx) { if (pol->type == type && pol->index == id && pol->if_id == if_id && xfrm_policy_mark_match(mark, pol)) { xfrm_pol_hold(pol); if (delete) { *err = security_xfrm_policy_delete( pol->security); if (*err) { spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return pol; } __xfrm_policy_unlink(pol, dir); } ret = pol; break; } } spin_unlock_bh(&net->xfrm.xfrm_policy_lock); if (ret && delete) xfrm_policy_kill(ret); return ret; } EXPORT_SYMBOL(xfrm_policy_byid); #ifdef CONFIG_SECURITY_NETWORK_XFRM static inline int xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) { struct xfrm_policy *pol; int err = 0; list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { if (pol->walk.dead || xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || pol->type != type) continue; err = security_xfrm_policy_delete(pol->security); if (err) { xfrm_audit_policy_delete(pol, 0, task_valid); return err; } } return err; } static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, struct net_device *dev, bool task_valid) { struct xfrm_policy *pol; int err = 0; list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { if (pol->walk.dead || xfrm_policy_id2dir(pol->index) >= XFRM_POLICY_MAX || pol->xdo.dev != dev) continue; err = security_xfrm_policy_delete(pol->security); if (err) { xfrm_audit_policy_delete(pol, 0, task_valid); return err; } } return err; } #else static inline int xfrm_policy_flush_secctx_check(struct net *net, u8 type, bool task_valid) { return 0; } static inline int xfrm_dev_policy_flush_secctx_check(struct net *net, struct net_device *dev, bool task_valid) { return 0; } #endif int xfrm_policy_flush(struct net *net, u8 type, bool task_valid) { int dir, err = 0, cnt = 0; struct xfrm_policy *pol; spin_lock_bh(&net->xfrm.xfrm_policy_lock); err = xfrm_policy_flush_secctx_check(net, type, task_valid); if (err) goto out; again: list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { if (pol->walk.dead) continue; dir = xfrm_policy_id2dir(pol->index); if (dir >= XFRM_POLICY_MAX || pol->type != type) continue; __xfrm_policy_unlink(pol, dir); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); xfrm_dev_policy_delete(pol); cnt++; xfrm_audit_policy_delete(pol, 1, task_valid); xfrm_policy_kill(pol); spin_lock_bh(&net->xfrm.xfrm_policy_lock); goto again; } if (cnt) __xfrm_policy_inexact_flush(net); else err = -ESRCH; out: spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return err; } EXPORT_SYMBOL(xfrm_policy_flush); int xfrm_dev_policy_flush(struct net *net, struct net_device *dev, bool task_valid) { int dir, err = 0, cnt = 0; struct xfrm_policy *pol; spin_lock_bh(&net->xfrm.xfrm_policy_lock); err = xfrm_dev_policy_flush_secctx_check(net, dev, task_valid); if (err) goto out; again: list_for_each_entry(pol, &net->xfrm.policy_all, walk.all) { if (pol->walk.dead) continue; dir = xfrm_policy_id2dir(pol->index); if (dir >= XFRM_POLICY_MAX || pol->xdo.dev != dev) continue; __xfrm_policy_unlink(pol, dir); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); xfrm_dev_policy_delete(pol); cnt++; xfrm_audit_policy_delete(pol, 1, task_valid); xfrm_policy_kill(pol); spin_lock_bh(&net->xfrm.xfrm_policy_lock); goto again; } if (cnt) __xfrm_policy_inexact_flush(net); else err = -ESRCH; out: spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return err; } EXPORT_SYMBOL(xfrm_dev_policy_flush); int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk, int (*func)(struct xfrm_policy *, int, int, void*), void *data) { struct xfrm_policy *pol; struct xfrm_policy_walk_entry *x; int error = 0; if (walk->type >= XFRM_POLICY_TYPE_MAX && walk->type != XFRM_POLICY_TYPE_ANY) return -EINVAL; if (list_empty(&walk->walk.all) && walk->seq != 0) return 0; spin_lock_bh(&net->xfrm.xfrm_policy_lock); if (list_empty(&walk->walk.all)) x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all); else x = list_first_entry(&walk->walk.all, struct xfrm_policy_walk_entry, all); list_for_each_entry_from(x, &net->xfrm.policy_all, all) { if (x->dead) continue; pol = container_of(x, struct xfrm_policy, walk); if (walk->type != XFRM_POLICY_TYPE_ANY && walk->type != pol->type) continue; error = func(pol, xfrm_policy_id2dir(pol->index), walk->seq, data); if (error) { list_move_tail(&walk->walk.all, &x->all); goto out; } walk->seq++; } if (walk->seq == 0) { error = -ENOENT; goto out; } list_del_init(&walk->walk.all); out: spin_unlock_bh(&net->xfrm.xfrm_policy_lock); return error; } EXPORT_SYMBOL(xfrm_policy_walk); void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type) { INIT_LIST_HEAD(&walk->walk.all); walk->walk.dead = 1; walk->type = type; walk->seq = 0; } EXPORT_SYMBOL(xfrm_policy_walk_init); void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net) { if (list_empty(&walk->walk.all)) return; spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */ list_del(&walk->walk.all); spin_unlock_bh(&net->xfrm.xfrm_policy_lock); } EXPORT_SYMBOL(xfrm_policy_walk_done); /* * Find policy to apply to this flow. * * Returns 0 if policy found, else an -errno. */ static int xfrm_policy_match(const struct xfrm_policy *pol, const struct flowi *fl, u8 type, u16 family, u32 if_id) { const struct xfrm_selector *sel = &pol->selector; int ret = -ESRCH; bool match; if (pol->family != family || pol->if_id != if_id || (fl->flowi_mark & pol->mark.m) != pol->mark.v || pol->type != type) return ret; match = xfrm_selector_match(sel, fl, family); if (match) ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid); return ret; } static struct xfrm_pol_inexact_node * xfrm_policy_lookup_inexact_addr(const struct rb_root *r, seqcount_spinlock_t *count, const xfrm_address_t *addr, u16 family) { const struct rb_node *parent; int seq; again: seq = read_seqcount_begin(count); parent = rcu_dereference_raw(r->rb_node); while (parent) { struct xfrm_pol_inexact_node *node; int delta; node = rb_entry(parent, struct xfrm_pol_inexact_node, node); delta = xfrm_policy_addr_delta(addr, &node->addr, node->prefixlen, family); if (delta < 0) { parent = rcu_dereference_raw(parent->rb_left); continue; } else if (delta > 0) { parent = rcu_dereference_raw(parent->rb_right); continue; } return node; } if (read_seqcount_retry(count, seq)) goto again; return NULL; } static bool xfrm_policy_find_inexact_candidates(struct xfrm_pol_inexact_candidates *cand, struct xfrm_pol_inexact_bin *b, const xfrm_address_t *saddr, const xfrm_address_t *daddr) { struct xfrm_pol_inexact_node *n; u16 family; if (!b) return false; family = b->k.family; memset(cand, 0, sizeof(*cand)); cand->res[XFRM_POL_CAND_ANY] = &b->hhead; n = xfrm_policy_lookup_inexact_addr(&b->root_d, &b->count, daddr, family); if (n) { cand->res[XFRM_POL_CAND_DADDR] = &n->hhead; n = xfrm_policy_lookup_inexact_addr(&n->root, &b->count, saddr, family); if (n) cand->res[XFRM_POL_CAND_BOTH] = &n->hhead; } n = xfrm_policy_lookup_inexact_addr(&b->root_s, &b->count, saddr, family); if (n) cand->res[XFRM_POL_CAND_SADDR] = &n->hhead; return true; } static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_lookup_rcu(struct net *net, u8 type, u16 family, u8 dir, u32 if_id) { struct xfrm_pol_inexact_key k = { .family = family, .type = type, .dir = dir, .if_id = if_id, }; write_pnet(&k.net, net); return rhashtable_lookup(&xfrm_policy_inexact_table, &k, xfrm_pol_inexact_params); } static struct xfrm_pol_inexact_bin * xfrm_policy_inexact_lookup(struct net *net, u8 type, u16 family, u8 dir, u32 if_id) { struct xfrm_pol_inexact_bin *bin; lockdep_assert_held(&net->xfrm.xfrm_policy_lock); rcu_read_lock(); bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); rcu_read_unlock(); return bin; } static struct xfrm_policy * __xfrm_policy_eval_candidates(struct hlist_head *chain, struct xfrm_policy *prefer, const struct flowi *fl, u8 type, u16 family, u32 if_id) { u32 priority = prefer ? prefer->priority : ~0u; struct xfrm_policy *pol; if (!chain) return NULL; hlist_for_each_entry_rcu(pol, chain, bydst) { int err; if (pol->priority > priority) break; err = xfrm_policy_match(pol, fl, type, family, if_id); if (err) { if (err != -ESRCH) return ERR_PTR(err); continue; } if (prefer) { /* matches. Is it older than *prefer? */ if (pol->priority == priority && prefer->pos < pol->pos) return prefer; } return pol; } return NULL; } static struct xfrm_policy * xfrm_policy_eval_candidates(struct xfrm_pol_inexact_candidates *cand, struct xfrm_policy *prefer, const struct flowi *fl, u8 type, u16 family, u32 if_id) { struct xfrm_policy *tmp; int i; for (i = 0; i < ARRAY_SIZE(cand->res); i++) { tmp = __xfrm_policy_eval_candidates(cand->res[i], prefer, fl, type, family, if_id); if (!tmp) continue; if (IS_ERR(tmp)) return tmp; prefer = tmp; } return prefer; } static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type, const struct flowi *fl, u16 family, u8 dir, u32 if_id) { struct xfrm_pol_inexact_candidates cand; const xfrm_address_t *daddr, *saddr; struct xfrm_pol_inexact_bin *bin; struct xfrm_policy *pol, *ret; struct hlist_head *chain; unsigned int sequence; int err; daddr = xfrm_flowi_daddr(fl, family); saddr = xfrm_flowi_saddr(fl, family); if (unlikely(!daddr || !saddr)) return NULL; rcu_read_lock(); retry: do { sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); chain = policy_hash_direct(net, daddr, saddr, family, dir); } while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)); ret = NULL; hlist_for_each_entry_rcu(pol, chain, bydst) { err = xfrm_policy_match(pol, fl, type, family, if_id); if (err) { if (err == -ESRCH) continue; else { ret = ERR_PTR(err); goto fail; } } else { ret = pol; break; } } if (ret && ret->xdo.type == XFRM_DEV_OFFLOAD_PACKET) goto skip_inexact; bin = xfrm_policy_inexact_lookup_rcu(net, type, family, dir, if_id); if (!bin || !xfrm_policy_find_inexact_candidates(&cand, bin, saddr, daddr)) goto skip_inexact; pol = xfrm_policy_eval_candidates(&cand, ret, fl, type, family, if_id); if (pol) { ret = pol; if (IS_ERR(pol)) goto fail; } skip_inexact: if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)) goto retry; if (ret && !xfrm_pol_hold_rcu(ret)) goto retry; fail: rcu_read_unlock(); return ret; } static struct xfrm_policy *xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, u32 if_id) { #ifdef CONFIG_XFRM_SUB_POLICY struct xfrm_policy *pol; pol = xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_SUB, fl, family, dir, if_id); if (pol != NULL) return pol; #endif return xfrm_policy_lookup_bytype(net, XFRM_POLICY_TYPE_MAIN, fl, family, dir, if_id); } static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, const struct flowi *fl, u16 family, u32 if_id) { struct xfrm_policy *pol; rcu_read_lock(); again: pol = rcu_dereference(sk->sk_policy[dir]); if (pol != NULL) { bool match; int err = 0; if (pol->family != family) { pol = NULL; goto out; } match = xfrm_selector_match(&pol->selector, fl, family); if (match) { if ((READ_ONCE(sk->sk_mark) & pol->mark.m) != pol->mark.v || pol->if_id != if_id) { pol = NULL; goto out; } err = security_xfrm_policy_lookup(pol->security, fl->flowi_secid); if (!err) { if (!xfrm_pol_hold_rcu(pol)) goto again; } else if (err == -ESRCH) { pol = NULL; } else { pol = ERR_PTR(err); } } else pol = NULL; } out: rcu_read_unlock(); return pol; } static 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_dev_policy_delete(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, 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]); if (xfrm[i]->xso.type != XFRM_DEV_OFFLOAD_PACKET) family = xfrm[i]->props.family; oif = fl->flowi_oif ? : fl->flowi_l3mdev; dst = xfrm_dst_lookup(xfrm[i], tos, oif, &saddr, &daddr, family, mark); err = PTR_ERR(dst); if (IS_ERR(dst)) goto put_states; } else dst_hold(dst); dst1->xfrm = xfrm[i]; xdst->xfrm_genid = xfrm[i]->genid; dst1->obsolete = DST_OBSOLETE_FORCE_CHK; dst1->lastuse = now; dst1->input = dst_discard; rcu_read_lock(); afinfo = xfrm_state_afinfo_get_rcu(inner_mode->family); if (likely(afinfo)) dst1->output = afinfo->output; else dst1->output = dst_discard_out; rcu_read_unlock(); xdst_prev = xdst; header_len += xfrm[i]->props.header_len; if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT) nfheader_len += xfrm[i]->props.header_len; trailer_len += xfrm[i]->props.trailer_len; } xfrm_dst_set_child(xdst_prev, dst); xdst0->path = dst; err = -ENODEV; dev = dst->dev; if (!dev) goto free_dst; xfrm_init_path(xdst0, dst, nfheader_len); xfrm_init_pmtu(bundle, nx); for (xdst_prev = xdst0; xdst_prev != (struct xfrm_dst *)dst; xdst_prev = (struct xfrm_dst *) xfrm_dst_child(&xdst_prev->u.dst)) { err = xfrm_fill_dst(xdst_prev, dev, fl); if (err) goto free_dst; xdst_prev->u.dst.header_len = header_len; xdst_prev->u.dst.trailer_len = trailer_len; header_len -= xdst_prev->u.dst.xfrm->props.header_len; trailer_len -= xdst_prev->u.dst.xfrm->props.trailer_len; } return &xdst0->u.dst; put_states: for (; i < nx; i++) xfrm_state_put(xfrm[i]); free_dst: if (xdst0) dst_release_immediate(&xdst0->u.dst); return ERR_PTR(err); } static int xfrm_expand_policies(const struct flowi *fl, u16 family, struct xfrm_policy **pols, int *num_pols, int *num_xfrms) { int i; if (*num_pols == 0 || !pols[0]) { *num_pols = 0; *num_xfrms = 0; return 0; } if (IS_ERR(pols[0])) { *num_pols = 0; return PTR_ERR(pols[0]); } *num_xfrms = pols[0]->xfrm_nr; #ifdef CONFIG_XFRM_SUB_POLICY if (pols[0]->action == XFRM_POLICY_ALLOW && pols[0]->type != XFRM_POLICY_TYPE_MAIN) { pols[1] = xfrm_policy_lookup_bytype(xp_net(pols[0]), XFRM_POLICY_TYPE_MAIN, fl, family, XFRM_POLICY_OUT, pols[0]->if_id); if (pols[1]) { if (IS_ERR(pols[1])) { xfrm_pols_put(pols, *num_pols); *num_pols = 0; return PTR_ERR(pols[1]); } (*num_pols)++; (*num_xfrms) += pols[1]->xfrm_nr; } } #endif for (i = 0; i < *num_pols; i++) { if (pols[i]->action != XFRM_POLICY_ALLOW) { *num_xfrms = -1; break; } } return 0; } static struct xfrm_dst * xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols, const struct flowi *fl, u16 family, struct dst_entry *dst_orig) { struct net *net = xp_net(pols[0]); struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; struct xfrm_dst *bundle[XFRM_MAX_DEPTH]; struct xfrm_dst *xdst; struct dst_entry *dst; int err; /* Try to instantiate a bundle */ err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family); if (err <= 0) { if (err == 0) return NULL; if (err != -EAGAIN) XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); return ERR_PTR(err); } dst = xfrm_bundle_create(pols[0], xfrm, bundle, err, fl, dst_orig); if (IS_ERR(dst)) { XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTBUNDLEGENERROR); return ERR_CAST(dst); } xdst = (struct xfrm_dst *)dst; xdst->num_xfrms = err; xdst->num_pols = num_pols; memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); xdst->policy_genid = atomic_read(&pols[0]->genid); return xdst; } static void xfrm_policy_queue_process(struct timer_list *t) { struct sk_buff *skb; struct sock *sk; struct dst_entry *dst; struct xfrm_policy *pol = from_timer(pol, t, polq.hold_timer); struct net *net = xp_net(pol); struct xfrm_policy_queue *pq = &pol->polq; struct flowi fl; struct sk_buff_head list; __u32 skb_mark; spin_lock(&pq->hold_queue.lock); skb = skb_peek(&pq->hold_queue); if (!skb) { spin_unlock(&pq->hold_queue.lock); goto out; } dst = skb_dst(skb); sk = skb->sk; /* Fixup the mark to support VTI. */ skb_mark = skb->mark; skb->mark = pol->mark.v; xfrm_decode_session(net, skb, &fl, dst->ops->family); skb->mark = skb_mark; spin_unlock(&pq->hold_queue.lock); dst_hold(xfrm_dst_path(dst)); dst = xfrm_lookup(net, xfrm_dst_path(dst), &fl, sk, XFRM_LOOKUP_QUEUE); if (IS_ERR(dst)) goto purge_queue; if (dst->flags & DST_XFRM_QUEUE) { dst_release(dst); if (pq->timeout >= XFRM_QUEUE_TMO_MAX) goto purge_queue; pq->timeout = pq->timeout << 1; if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) xfrm_pol_hold(pol); goto out; } dst_release(dst); __skb_queue_head_init(&list); spin_lock(&pq->hold_queue.lock); pq->timeout = 0; skb_queue_splice_init(&pq->hold_queue, &list); spin_unlock(&pq->hold_queue.lock); while (!skb_queue_empty(&list)) { skb = __skb_dequeue(&list); /* Fixup the mark to support VTI. */ skb_mark = skb->mark; skb->mark = pol->mark.v; xfrm_decode_session(net, skb, &fl, skb_dst(skb)->ops->family); skb->mark = skb_mark; dst_hold(xfrm_dst_path(skb_dst(skb))); dst = xfrm_lookup(net, xfrm_dst_path(skb_dst(skb)), &fl, skb->sk, 0); if (IS_ERR(dst)) { kfree_skb(skb); continue; } nf_reset_ct(skb); skb_dst_drop(skb); skb_dst_set(skb, dst); dst_output(net, skb->sk, skb); } out: xfrm_pol_put(pol); return; purge_queue: pq->timeout = 0; skb_queue_purge(&pq->hold_queue); xfrm_pol_put(pol); } static int xdst_queue_output(struct net *net, struct sock *sk, struct sk_buff *skb) { unsigned long sched_next; struct dst_entry *dst = skb_dst(skb); struct xfrm_dst *xdst = (struct xfrm_dst *) dst; struct xfrm_policy *pol = xdst->pols[0]; struct xfrm_policy_queue *pq = &pol->polq; if (unlikely(skb_fclone_busy(sk, skb))) { kfree_skb(skb); return 0; } if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { kfree_skb(skb); return -EAGAIN; } skb_dst_force(skb); spin_lock_bh(&pq->hold_queue.lock); if (!pq->timeout) pq->timeout = XFRM_QUEUE_TMO_MIN; sched_next = jiffies + pq->timeout; if (del_timer(&pq->hold_timer)) { if (time_before(pq->hold_timer.expires, sched_next)) sched_next = pq->hold_timer.expires; xfrm_pol_put(pol); } __skb_queue_tail(&pq->hold_queue, skb); if (!mod_timer(&pq->hold_timer, sched_next)) xfrm_pol_hold(pol); spin_unlock_bh(&pq->hold_queue.lock); return 0; } static struct xfrm_dst *xfrm_create_dummy_bundle(struct net *net, struct xfrm_flo *xflo, const struct flowi *fl, int num_xfrms, u16 family) { int err; struct net_device *dev; struct dst_entry *dst; struct dst_entry *dst1; struct xfrm_dst *xdst; xdst = xfrm_alloc_dst(net, family); if (IS_ERR(xdst)) return xdst; if (!(xflo->flags & XFRM_LOOKUP_QUEUE) || net->xfrm.sysctl_larval_drop || num_xfrms <= 0) return xdst; dst = xflo->dst_orig; dst1 = &xdst->u.dst; dst_hold(dst); xdst->route = dst; dst_copy_metrics(dst1, dst); dst1->obsolete = DST_OBSOLETE_FORCE_CHK; dst1->flags |= DST_XFRM_QUEUE; dst1->lastuse = jiffies; dst1->input = dst_discard; dst1->output = xdst_queue_output; dst_hold(dst); xfrm_dst_set_child(xdst, dst); xdst->path = dst; xfrm_init_path((struct xfrm_dst *)dst1, dst, 0); err = -ENODEV; dev = dst->dev; if (!dev) goto free_dst; err = xfrm_fill_dst(xdst, dev, fl); if (err) goto free_dst; out: return xdst; free_dst: dst_release(dst1); xdst = ERR_PTR(err); goto out; } static struct xfrm_dst *xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir, struct xfrm_flo *xflo, u32 if_id) { struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; int num_pols = 0, num_xfrms = 0, err; struct xfrm_dst *xdst; /* Resolve policies to use if we couldn't get them from * previous cache entry */ num_pols = 1; pols[0] = xfrm_policy_lookup(net, fl, family, dir, if_id); err = xfrm_expand_policies(fl, family, pols, &num_pols, &num_xfrms); if (err < 0) goto inc_error; if (num_pols == 0) return NULL; if (num_xfrms <= 0) goto make_dummy_bundle; xdst = xfrm_resolve_and_create_bundle(pols, num_pols, fl, family, xflo->dst_orig); if (IS_ERR(xdst)) { err = PTR_ERR(xdst); if (err == -EREMOTE) { xfrm_pols_put(pols, num_pols); return NULL; } if (err != -EAGAIN) goto error; goto make_dummy_bundle; } else if (xdst == NULL) { num_xfrms = 0; goto make_dummy_bundle; } return xdst; make_dummy_bundle: /* We found policies, but there's no bundles to instantiate: * either because the policy blocks, has no transformations or * we could not build template (no xfrm_states).*/ xdst = xfrm_create_dummy_bundle(net, xflo, fl, num_xfrms, family); if (IS_ERR(xdst)) { xfrm_pols_put(pols, num_pols); return ERR_CAST(xdst); } xdst->num_pols = num_pols; xdst->num_xfrms = num_xfrms; memcpy(xdst->pols, pols, sizeof(struct xfrm_policy *) * num_pols); return xdst; inc_error: XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR); error: xfrm_pols_put(pols, num_pols); return ERR_PTR(err); } static struct dst_entry *make_blackhole(struct net *net, u16 family, struct dst_entry *dst_orig) { const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); struct dst_entry *ret; if (!afinfo) { dst_release(dst_orig); return ERR_PTR(-EINVAL); } else { ret = afinfo->blackhole_route(net, dst_orig); } rcu_read_unlock(); return ret; } /* Finds/creates a bundle for given flow and if_id * * At the moment we eat a raw IP route. Mostly to speed up lookups * on interfaces with disabled IPsec. * * xfrm_lookup uses an if_id of 0 by default, and is provided for * compatibility */ struct dst_entry *xfrm_lookup_with_ifid(struct net *net, struct dst_entry *dst_orig, const struct flowi *fl, const struct sock *sk, int flags, u32 if_id) { struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; struct xfrm_dst *xdst; struct dst_entry *dst, *route; u16 family = dst_orig->ops->family; u8 dir = XFRM_POLICY_OUT; int i, err, num_pols, num_xfrms = 0, drop_pols = 0; dst = NULL; xdst = NULL; route = NULL; sk = sk_const_to_full_sk(sk); if (sk && sk->sk_policy[XFRM_POLICY_OUT]) { num_pols = 1; pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family, if_id); err = xfrm_expand_policies(fl, family, pols, &num_pols, &num_xfrms); if (err < 0) goto dropdst; if (num_pols) { if (num_xfrms <= 0) { drop_pols = num_pols; goto no_transform; } xdst = xfrm_resolve_and_create_bundle( pols, num_pols, fl, family, dst_orig); if (IS_ERR(xdst)) { xfrm_pols_put(pols, num_pols); err = PTR_ERR(xdst); if (err == -EREMOTE) goto nopol; goto dropdst; } else if (xdst == NULL) { num_xfrms = 0; drop_pols = num_pols; goto no_transform; } route = xdst->route; } } if (xdst == NULL) { struct xfrm_flo xflo; xflo.dst_orig = dst_orig; xflo.flags = flags; /* To accelerate a bit... */ if (!if_id && ((dst_orig->flags & DST_NOXFRM) || !net->xfrm.policy_count[XFRM_POLICY_OUT])) goto nopol; xdst = xfrm_bundle_lookup(net, fl, family, dir, &xflo, if_id); if (xdst == NULL) goto nopol; if (IS_ERR(xdst)) { err = PTR_ERR(xdst); goto dropdst; } num_pols = xdst->num_pols; num_xfrms = xdst->num_xfrms; memcpy(pols, xdst->pols, sizeof(struct xfrm_policy *) * num_pols); route = xdst->route; } dst = &xdst->u.dst; if (route == NULL && num_xfrms > 0) { /* The only case when xfrm_bundle_lookup() returns a * bundle with null route, is when the template could * not be resolved. It means policies are there, but * bundle could not be created, since we don't yet * have the xfrm_state's. We need to wait for KM to * negotiate new SA's or bail out with error.*/ if (net->xfrm.sysctl_larval_drop) { XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); err = -EREMOTE; goto error; } err = -EAGAIN; XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES); goto error; } no_transform: if (num_pols == 0) goto nopol; if ((flags & XFRM_LOOKUP_ICMP) && !(pols[0]->flags & XFRM_POLICY_ICMP)) { err = -ENOENT; goto error; } for (i = 0; i < num_pols; i++) WRITE_ONCE(pols[i]->curlft.use_time, ktime_get_real_seconds()); if (num_xfrms < 0) { /* Prohibit the flow */ XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLBLOCK); err = -EPERM; goto error; } else if (num_xfrms > 0) { /* Flow transformed */ dst_release(dst_orig); } else { /* Flow passes untransformed */ dst_release(dst); dst = dst_orig; } ok: xfrm_pols_put(pols, drop_pols); if (dst && dst->xfrm && dst->xfrm->props.mode == XFRM_MODE_TUNNEL) dst->flags |= DST_XFRM_TUNNEL; return dst; nopol: if ((!dst_orig->dev || !(dst_orig->dev->flags & IFF_LOOPBACK)) && net->xfrm.policy_default[dir] == XFRM_USERPOLICY_BLOCK) { err = -EPERM; goto error; } if (!(flags & XFRM_LOOKUP_ICMP)) { dst = dst_orig; goto ok; } err = -ENOENT; error: dst_release(dst); dropdst: if (!(flags & XFRM_LOOKUP_KEEP_DST_REF)) dst_release(dst_orig); xfrm_pols_put(pols, drop_pols); return ERR_PTR(err); } EXPORT_SYMBOL(xfrm_lookup_with_ifid); /* Main function: finds/creates a bundle for given flow. * * At the moment we eat a raw IP route. Mostly to speed up lookups * on interfaces with disabled IPsec. */ struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig, const struct flowi *fl, const struct sock *sk, int flags) { return xfrm_lookup_with_ifid(net, dst_orig, fl, sk, flags, 0); } EXPORT_SYMBOL(xfrm_lookup); /* Callers of xfrm_lookup_route() must ensure a call to dst_output(). * Otherwise we may send out blackholed packets. */ struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig, const struct flowi *fl, const struct sock *sk, int flags) { struct dst_entry *dst = xfrm_lookup(net, dst_orig, fl, sk, flags | XFRM_LOOKUP_QUEUE | XFRM_LOOKUP_KEEP_DST_REF); if (PTR_ERR(dst) == -EREMOTE) return make_blackhole(net, dst_orig->ops->family, dst_orig); if (IS_ERR(dst)) dst_release(dst_orig); return dst; } EXPORT_SYMBOL(xfrm_lookup_route); static inline int xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl) { struct sec_path *sp = skb_sec_path(skb); struct xfrm_state *x; if (!sp || idx < 0 || idx >= sp->len) return 0; x = sp->xvec[idx]; if (!x->type->reject) return 0; return x->type->reject(x, skb, fl); } /* When skb is transformed back to its "native" form, we have to * check policy restrictions. At the moment we make this in maximally * stupid way. Shame on me. :-) Of course, connected sockets must * have policy cached at them. */ static inline int xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, unsigned short family, u32 if_id) { if (xfrm_state_kern(x)) return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, tmpl->encap_family); return x->id.proto == tmpl->id.proto && (x->id.spi == tmpl->id.spi || !tmpl->id.spi) && (x->props.reqid == tmpl->reqid || !tmpl->reqid) && x->props.mode == tmpl->mode && (tmpl->allalgs || (tmpl->aalgos & (1<props.aalgo)) || !(xfrm_id_proto_match(tmpl->id.proto, IPSEC_PROTO_ANY))) && !(x->props.mode != XFRM_MODE_TRANSPORT && xfrm_state_addr_cmp(tmpl, x, family)) && (if_id == 0 || if_id == x->if_id); } /* * 0 or more than 0 is returned when validation is succeeded (either bypass * because of optional transport mode, or next index of the matched secpath * state with the template. * -1 is returned when no matching template is found. * Otherwise "-2 - errored_index" is returned. */ static inline int xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start, unsigned short family, u32 if_id) { int idx = start; if (tmpl->optional) { if (tmpl->mode == XFRM_MODE_TRANSPORT) return start; } else start = -1; for (; idx < sp->len; idx++) { if (xfrm_state_ok(tmpl, sp->xvec[idx], family, if_id)) return ++idx; if (sp->xvec[idx]->props.mode != XFRM_MODE_TRANSPORT) { if (idx < sp->verified_cnt) { /* Secpath entry previously verified, consider optional and * continue searching */ continue; } if (start == -1) start = -2-idx; break; } } return start; } static void decode_session4(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse) { struct flowi4 *fl4 = &fl->u.ip4; memset(fl4, 0, sizeof(struct flowi4)); if (reverse) { fl4->saddr = flkeys->addrs.ipv4.dst; fl4->daddr = flkeys->addrs.ipv4.src; fl4->fl4_sport = flkeys->ports.dst; fl4->fl4_dport = flkeys->ports.src; } else { fl4->saddr = flkeys->addrs.ipv4.src; fl4->daddr = flkeys->addrs.ipv4.dst; fl4->fl4_sport = flkeys->ports.src; fl4->fl4_dport = flkeys->ports.dst; } switch (flkeys->basic.ip_proto) { case IPPROTO_GRE: fl4->fl4_gre_key = flkeys->gre.keyid; break; case IPPROTO_ICMP: fl4->fl4_icmp_type = flkeys->icmp.type; fl4->fl4_icmp_code = flkeys->icmp.code; break; } fl4->flowi4_proto = flkeys->basic.ip_proto; fl4->flowi4_tos = flkeys->ip.tos & ~INET_ECN_MASK; } #if IS_ENABLED(CONFIG_IPV6) static void decode_session6(const struct xfrm_flow_keys *flkeys, struct flowi *fl, bool reverse) { struct flowi6 *fl6 = &fl->u.ip6; memset(fl6, 0, sizeof(struct flowi6)); if (reverse) { fl6->saddr = flkeys->addrs.ipv6.dst; fl6->daddr = flkeys->addrs.ipv6.src; fl6->fl6_sport = flkeys->ports.dst; fl6->fl6_dport = flkeys->ports.src; } else { fl6->saddr = flkeys->addrs.ipv6.src; fl6->daddr = flkeys->addrs.ipv6.dst; fl6->fl6_sport = flkeys->ports.src; fl6->fl6_dport = flkeys->ports.dst; } switch (flkeys->basic.ip_proto) { case IPPROTO_GRE: fl6->fl6_gre_key = flkeys->gre.keyid; break; case IPPROTO_ICMPV6: fl6->fl6_icmp_type = flkeys->icmp.type; fl6->fl6_icmp_code = flkeys->icmp.code; break; } fl6->flowi6_proto = flkeys->basic.ip_proto; } #endif int __xfrm_decode_session(struct net *net, struct sk_buff *skb, struct flowi *fl, unsigned int family, int reverse) { struct xfrm_flow_keys flkeys; memset(&flkeys, 0, sizeof(flkeys)); __skb_flow_dissect(net, skb, &xfrm_session_dissector, &flkeys, NULL, 0, 0, 0, FLOW_DISSECTOR_F_STOP_AT_ENCAP); switch (family) { case AF_INET: decode_session4(&flkeys, fl, reverse); break; #if IS_ENABLED(CONFIG_IPV6) case AF_INET6: decode_session6(&flkeys, fl, reverse); break; #endif default: return -EAFNOSUPPORT; } fl->flowi_mark = skb->mark; if (reverse) { fl->flowi_oif = skb->skb_iif; } else { int oif = 0; if (skb_dst(skb) && skb_dst(skb)->dev) oif = skb_dst(skb)->dev->ifindex; fl->flowi_oif = oif; } return security_xfrm_decode_session(skb, &fl->flowi_secid); } EXPORT_SYMBOL(__xfrm_decode_session); static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp) { for (; k < sp->len; k++) { if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) { *idxp = k; return 1; } } return 0; } int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family) { struct net *net = dev_net(skb->dev); struct xfrm_policy *pol; struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX]; int npols = 0; int xfrm_nr; int pi; int reverse; struct flowi fl; int xerr_idx = -1; const struct xfrm_if_cb *ifcb; struct sec_path *sp; u32 if_id = 0; rcu_read_lock(); ifcb = xfrm_if_get_cb(); if (ifcb) { struct xfrm_if_decode_session_result r; if (ifcb->decode_session(skb, family, &r)) { if_id = r.if_id; net = r.net; } } rcu_read_unlock(); reverse = dir & ~XFRM_POLICY_MASK; dir &= XFRM_POLICY_MASK; if (__xfrm_decode_session(net, skb, &fl, family, reverse) < 0) { XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); return 0; } nf_nat_decode_session(skb, &fl, family); /* First, check used SA against their selectors. */ sp = skb_sec_path(skb); if (sp) { int i; for (i = sp->len - 1; i >= 0; i--) { struct xfrm_state *x = sp->xvec[i]; 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(net, skb, &fl, family) < 0) { XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); return 0; } skb_dst_force(skb); if (!skb_dst(skb)) { XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR); return 0; } dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, XFRM_LOOKUP_QUEUE); if (IS_ERR(dst)) { res = 0; dst = NULL; } 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, }; static const struct flow_dissector_key xfrm_flow_dissector_keys[] = { { .key_id = FLOW_DISSECTOR_KEY_CONTROL, .offset = offsetof(struct xfrm_flow_keys, control), }, { .key_id = FLOW_DISSECTOR_KEY_BASIC, .offset = offsetof(struct xfrm_flow_keys, basic), }, { .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS, .offset = offsetof(struct xfrm_flow_keys, addrs.ipv4), }, { .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS, .offset = offsetof(struct xfrm_flow_keys, addrs.ipv6), }, { .key_id = FLOW_DISSECTOR_KEY_PORTS, .offset = offsetof(struct xfrm_flow_keys, ports), }, { .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID, .offset = offsetof(struct xfrm_flow_keys, gre), }, { .key_id = FLOW_DISSECTOR_KEY_IP, .offset = offsetof(struct xfrm_flow_keys, ip), }, { .key_id = FLOW_DISSECTOR_KEY_ICMP, .offset = offsetof(struct xfrm_flow_keys, icmp), }, }; void __init xfrm_init(void) { skb_flow_dissector_init(&xfrm_session_dissector, xfrm_flow_dissector_keys, ARRAY_SIZE(xfrm_flow_dissector_keys)); register_pernet_subsys(&xfrm_net_ops); xfrm_dev_init(); xfrm_input_init(); #ifdef CONFIG_XFRM_ESPINTCP espintcp_init(); #endif } #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 netlink_ext_ack *extack) { struct xfrm_migrate *mp; int i, j, n = 0; write_lock_bh(&pol->lock); if (unlikely(pol->walk.dead)) { /* target policy has been deleted */ NL_SET_ERR_MSG(extack, "Target policy not found"); write_unlock_bh(&pol->lock); return -ENOENT; } for (i = 0; i < pol->xfrm_nr; i++) { for (j = 0, mp = m; j < num_migrate; j++, mp++) { if (!migrate_tmpl_match(mp, &pol->xfrm_vec[i])) continue; n++; if (pol->xfrm_vec[i].mode != XFRM_MODE_TUNNEL && pol->xfrm_vec[i].mode != XFRM_MODE_BEET) continue; /* update endpoints */ memcpy(&pol->xfrm_vec[i].id.daddr, &mp->new_daddr, sizeof(pol->xfrm_vec[i].id.daddr)); memcpy(&pol->xfrm_vec[i].saddr, &mp->new_saddr, sizeof(pol->xfrm_vec[i].saddr)); pol->xfrm_vec[i].encap_family = mp->new_family; /* flush bundles */ atomic_inc(&pol->genid); } } write_unlock_bh(&pol->lock); if (!n) return -ENODATA; return 0; } static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate, struct netlink_ext_ack *extack) { int i, j; if (num_migrate < 1 || num_migrate > XFRM_MAX_DEPTH) { NL_SET_ERR_MSG(extack, "Invalid number of SAs to migrate, must be 0 < num <= XFRM_MAX_DEPTH (6)"); return -EINVAL; } for (i = 0; i < num_migrate; i++) { if (xfrm_addr_any(&m[i].new_daddr, m[i].new_family) || xfrm_addr_any(&m[i].new_saddr, m[i].new_family)) { NL_SET_ERR_MSG(extack, "Addresses in the MIGRATE attribute's list cannot be null"); return -EINVAL; } /* check if there is any duplicated entry */ for (j = i + 1; j < num_migrate; j++) { if (!memcmp(&m[i].old_daddr, &m[j].old_daddr, sizeof(m[i].old_daddr)) && !memcmp(&m[i].old_saddr, &m[j].old_saddr, sizeof(m[i].old_saddr)) && m[i].proto == m[j].proto && m[i].mode == m[j].mode && m[i].reqid == m[j].reqid && m[i].old_family == m[j].old_family) { NL_SET_ERR_MSG(extack, "Entries in the MIGRATE attribute's list must be unique"); return -EINVAL; } } } return 0; } int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, struct xfrm_migrate *m, int num_migrate, struct xfrm_kmaddress *k, struct net *net, struct xfrm_encap_tmpl *encap, u32 if_id, struct netlink_ext_ack *extack) { int i, err, nx_cur = 0, nx_new = 0; struct xfrm_policy *pol = NULL; struct xfrm_state *x, *xc; struct xfrm_state *x_cur[XFRM_MAX_DEPTH]; struct xfrm_state *x_new[XFRM_MAX_DEPTH]; struct xfrm_migrate *mp; /* Stage 0 - sanity checks */ err = xfrm_migrate_check(m, num_migrate, extack); if (err < 0) goto out; if (dir >= XFRM_POLICY_MAX) { NL_SET_ERR_MSG(extack, "Invalid policy direction"); err = -EINVAL; goto out; } /* Stage 1 - find policy */ pol = xfrm_migrate_policy_find(sel, dir, type, net, if_id); if (!pol) { NL_SET_ERR_MSG(extack, "Target policy not found"); 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 */ err = xfrm_policy_migrate(pol, m, num_migrate, extack); if (err < 0) goto restore_state; /* Stage 4 - delete old state(s) */ if (nx_cur) { xfrm_states_put(x_cur, nx_cur); xfrm_states_delete(x_cur, nx_cur); } /* Stage 5 - announce */ km_migrate(sel, dir, type, m, num_migrate, k, encap); xfrm_pol_put(pol); return 0; out: return err; restore_state: if (pol) xfrm_pol_put(pol); if (nx_cur) xfrm_states_put(x_cur, nx_cur); if (nx_new) xfrm_states_delete(x_new, nx_new); return err; } EXPORT_SYMBOL(xfrm_migrate); #endif