| /* |
| * xfrm_policy.c |
| * |
| * Changes: |
| * Mitsuru KANDA @USAGI |
| * Kazunori MIYAZAWA @USAGI |
| * Kunihiro Ishiguro <kunihiro@ipinfusion.com> |
| * IPv6 support |
| * Kazunori MIYAZAWA @USAGI |
| * YOSHIFUJI Hideaki |
| * Split up af-specific portion |
| * Derek Atkins <derek@ihtfp.com> Add the post_input processor |
| * |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/slab.h> |
| #include <linux/kmod.h> |
| #include <linux/list.h> |
| #include <linux/spinlock.h> |
| #include <linux/workqueue.h> |
| #include <linux/notifier.h> |
| #include <linux/netdevice.h> |
| #include <linux/netfilter.h> |
| #include <linux/module.h> |
| #include <net/xfrm.h> |
| #include <net/ip.h> |
| |
| DECLARE_MUTEX(xfrm_cfg_sem); |
| EXPORT_SYMBOL(xfrm_cfg_sem); |
| |
| static DEFINE_RWLOCK(xfrm_policy_lock); |
| |
| struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2]; |
| EXPORT_SYMBOL(xfrm_policy_list); |
| |
| static DEFINE_RWLOCK(xfrm_policy_afinfo_lock); |
| static struct xfrm_policy_afinfo *xfrm_policy_afinfo[NPROTO]; |
| |
| static kmem_cache_t *xfrm_dst_cache __read_mostly; |
| |
| static struct work_struct xfrm_policy_gc_work; |
| static struct list_head xfrm_policy_gc_list = |
| LIST_HEAD_INIT(xfrm_policy_gc_list); |
| static DEFINE_SPINLOCK(xfrm_policy_gc_lock); |
| |
| static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family); |
| static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo); |
| |
| int xfrm_register_type(struct xfrm_type *type, unsigned short family) |
| { |
| struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| struct xfrm_type_map *typemap; |
| int err = 0; |
| |
| if (unlikely(afinfo == NULL)) |
| return -EAFNOSUPPORT; |
| typemap = afinfo->type_map; |
| |
| write_lock(&typemap->lock); |
| if (likely(typemap->map[type->proto] == NULL)) |
| typemap->map[type->proto] = type; |
| else |
| err = -EEXIST; |
| write_unlock(&typemap->lock); |
| xfrm_policy_put_afinfo(afinfo); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_register_type); |
| |
| int xfrm_unregister_type(struct xfrm_type *type, unsigned short family) |
| { |
| struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| struct xfrm_type_map *typemap; |
| int err = 0; |
| |
| if (unlikely(afinfo == NULL)) |
| return -EAFNOSUPPORT; |
| typemap = afinfo->type_map; |
| |
| write_lock(&typemap->lock); |
| if (unlikely(typemap->map[type->proto] != type)) |
| err = -ENOENT; |
| else |
| typemap->map[type->proto] = NULL; |
| write_unlock(&typemap->lock); |
| xfrm_policy_put_afinfo(afinfo); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_unregister_type); |
| |
| struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family) |
| { |
| struct xfrm_policy_afinfo *afinfo; |
| struct xfrm_type_map *typemap; |
| struct xfrm_type *type; |
| int modload_attempted = 0; |
| |
| retry: |
| afinfo = xfrm_policy_get_afinfo(family); |
| if (unlikely(afinfo == NULL)) |
| return NULL; |
| typemap = afinfo->type_map; |
| |
| read_lock(&typemap->lock); |
| type = typemap->map[proto]; |
| if (unlikely(type && !try_module_get(type->owner))) |
| type = NULL; |
| read_unlock(&typemap->lock); |
| if (!type && !modload_attempted) { |
| xfrm_policy_put_afinfo(afinfo); |
| request_module("xfrm-type-%d-%d", |
| (int) family, (int) proto); |
| modload_attempted = 1; |
| goto retry; |
| } |
| |
| xfrm_policy_put_afinfo(afinfo); |
| return type; |
| } |
| |
| int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, |
| unsigned short family) |
| { |
| struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| int err = 0; |
| |
| if (unlikely(afinfo == NULL)) |
| return -EAFNOSUPPORT; |
| |
| if (likely(afinfo->dst_lookup != NULL)) |
| err = afinfo->dst_lookup(dst, fl); |
| else |
| err = -EINVAL; |
| xfrm_policy_put_afinfo(afinfo); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_dst_lookup); |
| |
| void xfrm_put_type(struct xfrm_type *type) |
| { |
| module_put(type->owner); |
| } |
| |
| 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(unsigned long data) |
| { |
| struct xfrm_policy *xp = (struct xfrm_policy*)data; |
| unsigned long now = (unsigned long)xtime.tv_sec; |
| long next = LONG_MAX; |
| int warn = 0; |
| int dir; |
| |
| read_lock(&xp->lock); |
| |
| if (xp->dead) |
| goto out; |
| |
| dir = xfrm_policy_id2dir(xp->index); |
| |
| if (xp->lft.hard_add_expires_seconds) { |
| long 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) { |
| long tmo = xp->lft.hard_use_expires_seconds + |
| (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) { |
| long 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) { |
| long tmo = xp->lft.soft_use_expires_seconds + |
| (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 != LONG_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(gfp_t gfp) |
| { |
| struct xfrm_policy *policy; |
| |
| policy = kmalloc(sizeof(struct xfrm_policy), gfp); |
| |
| if (policy) { |
| memset(policy, 0, sizeof(struct xfrm_policy)); |
| atomic_set(&policy->refcnt, 1); |
| rwlock_init(&policy->lock); |
| init_timer(&policy->timer); |
| policy->timer.data = (unsigned long)policy; |
| policy->timer.function = xfrm_policy_timer; |
| } |
| return policy; |
| } |
| EXPORT_SYMBOL(xfrm_policy_alloc); |
| |
| /* Destroy xfrm_policy: descendant resources must be released to this moment. */ |
| |
| void __xfrm_policy_destroy(struct xfrm_policy *policy) |
| { |
| BUG_ON(!policy->dead); |
| |
| BUG_ON(policy->bundles); |
| |
| if (del_timer(&policy->timer)) |
| BUG(); |
| |
| security_xfrm_policy_free(policy); |
| kfree(policy); |
| } |
| EXPORT_SYMBOL(__xfrm_policy_destroy); |
| |
| static void xfrm_policy_gc_kill(struct xfrm_policy *policy) |
| { |
| struct dst_entry *dst; |
| |
| while ((dst = policy->bundles) != NULL) { |
| policy->bundles = dst->next; |
| dst_free(dst); |
| } |
| |
| if (del_timer(&policy->timer)) |
| atomic_dec(&policy->refcnt); |
| |
| if (atomic_read(&policy->refcnt) > 1) |
| flow_cache_flush(); |
| |
| xfrm_pol_put(policy); |
| } |
| |
| static void xfrm_policy_gc_task(void *data) |
| { |
| struct xfrm_policy *policy; |
| struct list_head *entry, *tmp; |
| struct list_head gc_list = LIST_HEAD_INIT(gc_list); |
| |
| spin_lock_bh(&xfrm_policy_gc_lock); |
| list_splice_init(&xfrm_policy_gc_list, &gc_list); |
| spin_unlock_bh(&xfrm_policy_gc_lock); |
| |
| list_for_each_safe(entry, tmp, &gc_list) { |
| policy = list_entry(entry, struct xfrm_policy, list); |
| xfrm_policy_gc_kill(policy); |
| } |
| } |
| |
| /* Rule must be locked. Release descentant resources, announce |
| * entry dead. The rule must be unlinked from lists to the moment. |
| */ |
| |
| static void xfrm_policy_kill(struct xfrm_policy *policy) |
| { |
| int dead; |
| |
| write_lock_bh(&policy->lock); |
| dead = policy->dead; |
| policy->dead = 1; |
| write_unlock_bh(&policy->lock); |
| |
| if (unlikely(dead)) { |
| WARN_ON(1); |
| return; |
| } |
| |
| spin_lock(&xfrm_policy_gc_lock); |
| list_add(&policy->list, &xfrm_policy_gc_list); |
| spin_unlock(&xfrm_policy_gc_lock); |
| |
| schedule_work(&xfrm_policy_gc_work); |
| } |
| |
| /* 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(int dir) |
| { |
| u32 idx; |
| struct xfrm_policy *p; |
| static u32 idx_generator; |
| |
| for (;;) { |
| idx = (idx_generator | dir); |
| idx_generator += 8; |
| if (idx == 0) |
| idx = 8; |
| for (p = xfrm_policy_list[dir]; p; p = p->next) { |
| if (p->index == idx) |
| break; |
| } |
| if (!p) |
| return idx; |
| } |
| } |
| |
| int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl) |
| { |
| struct xfrm_policy *pol, **p; |
| struct xfrm_policy *delpol = NULL; |
| struct xfrm_policy **newpos = NULL; |
| struct dst_entry *gc_list; |
| |
| write_lock_bh(&xfrm_policy_lock); |
| for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL;) { |
| if (!delpol && memcmp(&policy->selector, &pol->selector, sizeof(pol->selector)) == 0 && |
| xfrm_sec_ctx_match(pol->security, policy->security)) { |
| if (excl) { |
| write_unlock_bh(&xfrm_policy_lock); |
| return -EEXIST; |
| } |
| *p = pol->next; |
| delpol = pol; |
| if (policy->priority > pol->priority) |
| continue; |
| } else if (policy->priority >= pol->priority) { |
| p = &pol->next; |
| continue; |
| } |
| if (!newpos) |
| newpos = p; |
| if (delpol) |
| break; |
| p = &pol->next; |
| } |
| if (newpos) |
| p = newpos; |
| xfrm_pol_hold(policy); |
| policy->next = *p; |
| *p = policy; |
| atomic_inc(&flow_cache_genid); |
| policy->index = delpol ? delpol->index : xfrm_gen_index(dir); |
| policy->curlft.add_time = (unsigned long)xtime.tv_sec; |
| policy->curlft.use_time = 0; |
| if (!mod_timer(&policy->timer, jiffies + HZ)) |
| xfrm_pol_hold(policy); |
| write_unlock_bh(&xfrm_policy_lock); |
| |
| if (delpol) |
| xfrm_policy_kill(delpol); |
| |
| read_lock_bh(&xfrm_policy_lock); |
| gc_list = NULL; |
| for (policy = policy->next; policy; policy = policy->next) { |
| struct dst_entry *dst; |
| |
| write_lock(&policy->lock); |
| dst = policy->bundles; |
| if (dst) { |
| struct dst_entry *tail = dst; |
| while (tail->next) |
| tail = tail->next; |
| tail->next = gc_list; |
| gc_list = dst; |
| |
| policy->bundles = NULL; |
| } |
| write_unlock(&policy->lock); |
| } |
| read_unlock_bh(&xfrm_policy_lock); |
| |
| while (gc_list) { |
| struct dst_entry *dst = gc_list; |
| |
| gc_list = dst->next; |
| dst_free(dst); |
| } |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(xfrm_policy_insert); |
| |
| struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel, |
| struct xfrm_sec_ctx *ctx, int delete) |
| { |
| struct xfrm_policy *pol, **p; |
| |
| write_lock_bh(&xfrm_policy_lock); |
| for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) { |
| if ((memcmp(sel, &pol->selector, sizeof(*sel)) == 0) && |
| (xfrm_sec_ctx_match(ctx, pol->security))) { |
| xfrm_pol_hold(pol); |
| if (delete) |
| *p = pol->next; |
| break; |
| } |
| } |
| write_unlock_bh(&xfrm_policy_lock); |
| |
| if (pol && delete) { |
| atomic_inc(&flow_cache_genid); |
| xfrm_policy_kill(pol); |
| } |
| return pol; |
| } |
| EXPORT_SYMBOL(xfrm_policy_bysel_ctx); |
| |
| struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete) |
| { |
| struct xfrm_policy *pol, **p; |
| |
| write_lock_bh(&xfrm_policy_lock); |
| for (p = &xfrm_policy_list[dir]; (pol=*p)!=NULL; p = &pol->next) { |
| if (pol->index == id) { |
| xfrm_pol_hold(pol); |
| if (delete) |
| *p = pol->next; |
| break; |
| } |
| } |
| write_unlock_bh(&xfrm_policy_lock); |
| |
| if (pol && delete) { |
| atomic_inc(&flow_cache_genid); |
| xfrm_policy_kill(pol); |
| } |
| return pol; |
| } |
| EXPORT_SYMBOL(xfrm_policy_byid); |
| |
| void xfrm_policy_flush(void) |
| { |
| struct xfrm_policy *xp; |
| int dir; |
| |
| write_lock_bh(&xfrm_policy_lock); |
| for (dir = 0; dir < XFRM_POLICY_MAX; dir++) { |
| while ((xp = xfrm_policy_list[dir]) != NULL) { |
| xfrm_policy_list[dir] = xp->next; |
| write_unlock_bh(&xfrm_policy_lock); |
| |
| xfrm_policy_kill(xp); |
| |
| write_lock_bh(&xfrm_policy_lock); |
| } |
| } |
| atomic_inc(&flow_cache_genid); |
| write_unlock_bh(&xfrm_policy_lock); |
| } |
| EXPORT_SYMBOL(xfrm_policy_flush); |
| |
| int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), |
| void *data) |
| { |
| struct xfrm_policy *xp; |
| int dir; |
| int count = 0; |
| int error = 0; |
| |
| read_lock_bh(&xfrm_policy_lock); |
| for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) { |
| for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) |
| count++; |
| } |
| |
| if (count == 0) { |
| error = -ENOENT; |
| goto out; |
| } |
| |
| for (dir = 0; dir < 2*XFRM_POLICY_MAX; dir++) { |
| for (xp = xfrm_policy_list[dir]; xp; xp = xp->next) { |
| error = func(xp, dir%XFRM_POLICY_MAX, --count, data); |
| if (error) |
| goto out; |
| } |
| } |
| |
| out: |
| read_unlock_bh(&xfrm_policy_lock); |
| return error; |
| } |
| EXPORT_SYMBOL(xfrm_policy_walk); |
| |
| /* Find policy to apply to this flow. */ |
| |
| static void xfrm_policy_lookup(struct flowi *fl, u32 sk_sid, u16 family, u8 dir, |
| void **objp, atomic_t **obj_refp) |
| { |
| struct xfrm_policy *pol; |
| |
| read_lock_bh(&xfrm_policy_lock); |
| for (pol = xfrm_policy_list[dir]; pol; pol = pol->next) { |
| struct xfrm_selector *sel = &pol->selector; |
| int match; |
| |
| if (pol->family != family) |
| continue; |
| |
| match = xfrm_selector_match(sel, fl, family); |
| |
| if (match) { |
| if (!security_xfrm_policy_lookup(pol, sk_sid, dir)) { |
| xfrm_pol_hold(pol); |
| break; |
| } |
| } |
| } |
| read_unlock_bh(&xfrm_policy_lock); |
| if ((*objp = (void *) pol) != NULL) |
| *obj_refp = &pol->refcnt; |
| } |
| |
| static inline int policy_to_flow_dir(int dir) |
| { |
| if (XFRM_POLICY_IN == FLOW_DIR_IN && |
| XFRM_POLICY_OUT == FLOW_DIR_OUT && |
| XFRM_POLICY_FWD == FLOW_DIR_FWD) |
| return dir; |
| switch (dir) { |
| default: |
| case XFRM_POLICY_IN: |
| return FLOW_DIR_IN; |
| case XFRM_POLICY_OUT: |
| return FLOW_DIR_OUT; |
| case XFRM_POLICY_FWD: |
| return FLOW_DIR_FWD; |
| }; |
| } |
| |
| static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl, u32 sk_sid) |
| { |
| struct xfrm_policy *pol; |
| |
| read_lock_bh(&xfrm_policy_lock); |
| if ((pol = sk->sk_policy[dir]) != NULL) { |
| int match = xfrm_selector_match(&pol->selector, fl, |
| sk->sk_family); |
| int err = 0; |
| |
| if (match) |
| err = security_xfrm_policy_lookup(pol, sk_sid, policy_to_flow_dir(dir)); |
| |
| if (match && !err) |
| xfrm_pol_hold(pol); |
| else |
| pol = NULL; |
| } |
| read_unlock_bh(&xfrm_policy_lock); |
| return pol; |
| } |
| |
| static void __xfrm_policy_link(struct xfrm_policy *pol, int dir) |
| { |
| pol->next = xfrm_policy_list[dir]; |
| xfrm_policy_list[dir] = pol; |
| xfrm_pol_hold(pol); |
| } |
| |
| static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol, |
| int dir) |
| { |
| struct xfrm_policy **polp; |
| |
| for (polp = &xfrm_policy_list[dir]; |
| *polp != NULL; polp = &(*polp)->next) { |
| if (*polp == pol) { |
| *polp = pol->next; |
| return pol; |
| } |
| } |
| return NULL; |
| } |
| |
| int xfrm_policy_delete(struct xfrm_policy *pol, int dir) |
| { |
| write_lock_bh(&xfrm_policy_lock); |
| pol = __xfrm_policy_unlink(pol, dir); |
| write_unlock_bh(&xfrm_policy_lock); |
| if (pol) { |
| if (dir < XFRM_POLICY_MAX) |
| atomic_inc(&flow_cache_genid); |
| 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 xfrm_policy *old_pol; |
| |
| write_lock_bh(&xfrm_policy_lock); |
| old_pol = sk->sk_policy[dir]; |
| sk->sk_policy[dir] = pol; |
| if (pol) { |
| pol->curlft.add_time = (unsigned long)xtime.tv_sec; |
| pol->index = xfrm_gen_index(XFRM_POLICY_MAX+dir); |
| __xfrm_policy_link(pol, XFRM_POLICY_MAX+dir); |
| } |
| if (old_pol) |
| __xfrm_policy_unlink(old_pol, XFRM_POLICY_MAX+dir); |
| write_unlock_bh(&xfrm_policy_lock); |
| |
| if (old_pol) { |
| xfrm_policy_kill(old_pol); |
| } |
| return 0; |
| } |
| |
| static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir) |
| { |
| struct xfrm_policy *newp = xfrm_policy_alloc(GFP_ATOMIC); |
| |
| if (newp) { |
| newp->selector = old->selector; |
| if (security_xfrm_policy_clone(old, newp)) { |
| kfree(newp); |
| return NULL; /* ENOMEM */ |
| } |
| newp->lft = old->lft; |
| newp->curlft = old->curlft; |
| newp->action = old->action; |
| newp->flags = old->flags; |
| newp->xfrm_nr = old->xfrm_nr; |
| newp->index = old->index; |
| memcpy(newp->xfrm_vec, old->xfrm_vec, |
| newp->xfrm_nr*sizeof(struct xfrm_tmpl)); |
| write_lock_bh(&xfrm_policy_lock); |
| __xfrm_policy_link(newp, XFRM_POLICY_MAX+dir); |
| write_unlock_bh(&xfrm_policy_lock); |
| xfrm_pol_put(newp); |
| } |
| return newp; |
| } |
| |
| int __xfrm_sk_clone_policy(struct sock *sk) |
| { |
| struct xfrm_policy *p0 = sk->sk_policy[0], |
| *p1 = sk->sk_policy[1]; |
| |
| sk->sk_policy[0] = sk->sk_policy[1] = NULL; |
| if (p0 && (sk->sk_policy[0] = clone_policy(p0, 0)) == NULL) |
| return -ENOMEM; |
| if (p1 && (sk->sk_policy[1] = clone_policy(p1, 1)) == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| /* Resolve list of templates for the flow, given policy. */ |
| |
| static int |
| xfrm_tmpl_resolve(struct xfrm_policy *policy, struct flowi *fl, |
| struct xfrm_state **xfrm, |
| unsigned short family) |
| { |
| int nx; |
| int i, error; |
| xfrm_address_t *daddr = xfrm_flowi_daddr(fl, family); |
| xfrm_address_t *saddr = xfrm_flowi_saddr(fl, family); |
| |
| 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) { |
| remote = &tmpl->id.daddr; |
| local = &tmpl->saddr; |
| } |
| |
| x = xfrm_state_find(remote, local, fl, tmpl, policy, &error, family); |
| |
| 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); |
| } |
| |
| if (!tmpl->optional) |
| goto fail; |
| } |
| return nx; |
| |
| fail: |
| for (nx--; nx>=0; nx--) |
| xfrm_state_put(xfrm[nx]); |
| return error; |
| } |
| |
| /* Check that the bundle accepts the flow and its components are |
| * still valid. |
| */ |
| |
| static struct dst_entry * |
| xfrm_find_bundle(struct flowi *fl, struct xfrm_policy *policy, unsigned short family) |
| { |
| struct dst_entry *x; |
| struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| if (unlikely(afinfo == NULL)) |
| return ERR_PTR(-EINVAL); |
| x = afinfo->find_bundle(fl, policy); |
| xfrm_policy_put_afinfo(afinfo); |
| return x; |
| } |
| |
| /* Allocate chain of dst_entry's, attach known xfrm's, calculate |
| * all the metrics... Shortly, bundle a bundle. |
| */ |
| |
| static int |
| xfrm_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx, |
| struct flowi *fl, struct dst_entry **dst_p, |
| unsigned short family) |
| { |
| int err; |
| struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| if (unlikely(afinfo == NULL)) |
| return -EINVAL; |
| err = afinfo->bundle_create(policy, xfrm, nx, fl, dst_p); |
| xfrm_policy_put_afinfo(afinfo); |
| return err; |
| } |
| |
| |
| static int stale_bundle(struct dst_entry *dst); |
| |
| /* 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. |
| */ |
| int xfrm_lookup(struct dst_entry **dst_p, struct flowi *fl, |
| struct sock *sk, int flags) |
| { |
| struct xfrm_policy *policy; |
| struct xfrm_state *xfrm[XFRM_MAX_DEPTH]; |
| struct dst_entry *dst, *dst_orig = *dst_p; |
| int nx = 0; |
| int err; |
| u32 genid; |
| u16 family; |
| u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT); |
| u32 sk_sid = security_sk_sid(sk, fl, dir); |
| restart: |
| genid = atomic_read(&flow_cache_genid); |
| policy = NULL; |
| if (sk && sk->sk_policy[1]) |
| policy = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, sk_sid); |
| |
| if (!policy) { |
| /* To accelerate a bit... */ |
| if ((dst_orig->flags & DST_NOXFRM) || !xfrm_policy_list[XFRM_POLICY_OUT]) |
| return 0; |
| |
| policy = flow_cache_lookup(fl, sk_sid, dst_orig->ops->family, |
| dir, xfrm_policy_lookup); |
| } |
| |
| if (!policy) |
| return 0; |
| |
| family = dst_orig->ops->family; |
| policy->curlft.use_time = (unsigned long)xtime.tv_sec; |
| |
| switch (policy->action) { |
| case XFRM_POLICY_BLOCK: |
| /* Prohibit the flow */ |
| err = -EPERM; |
| goto error; |
| |
| case XFRM_POLICY_ALLOW: |
| if (policy->xfrm_nr == 0) { |
| /* Flow passes not transformed. */ |
| xfrm_pol_put(policy); |
| return 0; |
| } |
| |
| /* Try to find matching bundle. |
| * |
| * LATER: help from flow cache. It is optional, this |
| * is required only for output policy. |
| */ |
| dst = xfrm_find_bundle(fl, policy, family); |
| if (IS_ERR(dst)) { |
| err = PTR_ERR(dst); |
| goto error; |
| } |
| |
| if (dst) |
| break; |
| |
| nx = xfrm_tmpl_resolve(policy, fl, xfrm, family); |
| |
| if (unlikely(nx<0)) { |
| err = nx; |
| if (err == -EAGAIN && flags) { |
| DECLARE_WAITQUEUE(wait, current); |
| |
| add_wait_queue(&km_waitq, &wait); |
| set_current_state(TASK_INTERRUPTIBLE); |
| schedule(); |
| set_current_state(TASK_RUNNING); |
| remove_wait_queue(&km_waitq, &wait); |
| |
| nx = xfrm_tmpl_resolve(policy, fl, xfrm, family); |
| |
| if (nx == -EAGAIN && signal_pending(current)) { |
| err = -ERESTART; |
| goto error; |
| } |
| if (nx == -EAGAIN || |
| genid != atomic_read(&flow_cache_genid)) { |
| xfrm_pol_put(policy); |
| goto restart; |
| } |
| err = nx; |
| } |
| if (err < 0) |
| goto error; |
| } |
| if (nx == 0) { |
| /* Flow passes not transformed. */ |
| xfrm_pol_put(policy); |
| return 0; |
| } |
| |
| dst = dst_orig; |
| err = xfrm_bundle_create(policy, xfrm, nx, fl, &dst, family); |
| |
| if (unlikely(err)) { |
| int i; |
| for (i=0; i<nx; i++) |
| xfrm_state_put(xfrm[i]); |
| goto error; |
| } |
| |
| write_lock_bh(&policy->lock); |
| if (unlikely(policy->dead || stale_bundle(dst))) { |
| /* Wow! While we worked on resolving, this |
| * policy has gone. Retry. It is not paranoia, |
| * we just cannot enlist new bundle to dead object. |
| * We can't enlist stable bundles either. |
| */ |
| write_unlock_bh(&policy->lock); |
| if (dst) |
| dst_free(dst); |
| |
| err = -EHOSTUNREACH; |
| goto error; |
| } |
| dst->next = policy->bundles; |
| policy->bundles = dst; |
| dst_hold(dst); |
| write_unlock_bh(&policy->lock); |
| } |
| *dst_p = dst; |
| dst_release(dst_orig); |
| xfrm_pol_put(policy); |
| return 0; |
| |
| error: |
| dst_release(dst_orig); |
| xfrm_pol_put(policy); |
| *dst_p = NULL; |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_lookup); |
| |
| /* 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(struct xfrm_tmpl *tmpl, struct xfrm_state *x, |
| unsigned short family) |
| { |
| if (xfrm_state_kern(x)) |
| return tmpl->optional && !xfrm_state_addr_cmp(tmpl, x, 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->aalgos & (1<<x->props.aalgo)) && |
| !(x->props.mode && xfrm_state_addr_cmp(tmpl, x, family)); |
| } |
| |
| static inline int |
| xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start, |
| unsigned short family) |
| { |
| int idx = start; |
| |
| if (tmpl->optional) { |
| if (!tmpl->mode) |
| return start; |
| } else |
| start = -1; |
| for (; idx < sp->len; idx++) { |
| if (xfrm_state_ok(tmpl, sp->x[idx].xvec, family)) |
| return ++idx; |
| if (sp->x[idx].xvec->props.mode) |
| break; |
| } |
| return start; |
| } |
| |
| int |
| xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family) |
| { |
| struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family); |
| |
| if (unlikely(afinfo == NULL)) |
| return -EAFNOSUPPORT; |
| |
| afinfo->decode_session(skb, fl); |
| xfrm_policy_put_afinfo(afinfo); |
| return 0; |
| } |
| EXPORT_SYMBOL(xfrm_decode_session); |
| |
| static inline int secpath_has_tunnel(struct sec_path *sp, int k) |
| { |
| for (; k < sp->len; k++) { |
| if (sp->x[k].xvec->props.mode) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| int __xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, |
| unsigned short family) |
| { |
| struct xfrm_policy *pol; |
| struct flowi fl; |
| u8 fl_dir = policy_to_flow_dir(dir); |
| u32 sk_sid; |
| |
| if (xfrm_decode_session(skb, &fl, family) < 0) |
| return 0; |
| nf_nat_decode_session(skb, &fl, family); |
| |
| sk_sid = security_sk_sid(sk, &fl, fl_dir); |
| |
| /* First, check used SA against their selectors. */ |
| if (skb->sp) { |
| int i; |
| |
| for (i=skb->sp->len-1; i>=0; i--) { |
| struct sec_decap_state *xvec = &(skb->sp->x[i]); |
| if (!xfrm_selector_match(&xvec->xvec->sel, &fl, family)) |
| return 0; |
| } |
| } |
| |
| pol = NULL; |
| if (sk && sk->sk_policy[dir]) |
| pol = xfrm_sk_policy_lookup(sk, dir, &fl, sk_sid); |
| |
| if (!pol) |
| pol = flow_cache_lookup(&fl, sk_sid, family, fl_dir, |
| xfrm_policy_lookup); |
| |
| if (!pol) |
| return !skb->sp || !secpath_has_tunnel(skb->sp, 0); |
| |
| pol->curlft.use_time = (unsigned long)xtime.tv_sec; |
| |
| if (pol->action == XFRM_POLICY_ALLOW) { |
| struct sec_path *sp; |
| static struct sec_path dummy; |
| int i, k; |
| |
| if ((sp = skb->sp) == NULL) |
| sp = &dummy; |
| |
| /* 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. |
| */ |
| for (i = pol->xfrm_nr-1, k = 0; i >= 0; i--) { |
| k = xfrm_policy_ok(pol->xfrm_vec+i, sp, k, family); |
| if (k < 0) |
| goto reject; |
| } |
| |
| if (secpath_has_tunnel(sp, k)) |
| goto reject; |
| |
| xfrm_pol_put(pol); |
| return 1; |
| } |
| |
| reject: |
| xfrm_pol_put(pol); |
| return 0; |
| } |
| EXPORT_SYMBOL(__xfrm_policy_check); |
| |
| int __xfrm_route_forward(struct sk_buff *skb, unsigned short family) |
| { |
| struct flowi fl; |
| |
| if (xfrm_decode_session(skb, &fl, family) < 0) |
| return 0; |
| |
| return xfrm_lookup(&skb->dst, &fl, NULL, 0) == 0; |
| } |
| EXPORT_SYMBOL(__xfrm_route_forward); |
| |
| static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie) |
| { |
| /* If it is marked obsolete, which is how we even get here, |
| * then we have purged it from the policy bundle list and we |
| * did that for a good reason. |
| */ |
| return NULL; |
| } |
| |
| static int stale_bundle(struct dst_entry *dst) |
| { |
| return !xfrm_bundle_ok((struct xfrm_dst *)dst, NULL, AF_UNSPEC); |
| } |
| |
| void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev) |
| { |
| while ((dst = dst->child) && dst->xfrm && dst->dev == dev) { |
| dst->dev = &loopback_dev; |
| dev_hold(&loopback_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. */ |
| return; |
| } |
| |
| 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_prune_bundles(int (*func)(struct dst_entry *)) |
| { |
| int i; |
| struct xfrm_policy *pol; |
| struct dst_entry *dst, **dstp, *gc_list = NULL; |
| |
| read_lock_bh(&xfrm_policy_lock); |
| for (i=0; i<2*XFRM_POLICY_MAX; i++) { |
| for (pol = xfrm_policy_list[i]; pol; pol = pol->next) { |
| write_lock(&pol->lock); |
| dstp = &pol->bundles; |
| while ((dst=*dstp) != NULL) { |
| if (func(dst)) { |
| *dstp = dst->next; |
| dst->next = gc_list; |
| gc_list = dst; |
| } else { |
| dstp = &dst->next; |
| } |
| } |
| write_unlock(&pol->lock); |
| } |
| } |
| read_unlock_bh(&xfrm_policy_lock); |
| |
| while (gc_list) { |
| dst = gc_list; |
| gc_list = dst->next; |
| dst_free(dst); |
| } |
| } |
| |
| static int unused_bundle(struct dst_entry *dst) |
| { |
| return !atomic_read(&dst->__refcnt); |
| } |
| |
| static void __xfrm_garbage_collect(void) |
| { |
| xfrm_prune_bundles(unused_bundle); |
| } |
| |
| int xfrm_flush_bundles(void) |
| { |
| xfrm_prune_bundles(stale_bundle); |
| return 0; |
| } |
| |
| static int always_true(struct dst_entry *dst) |
| { |
| return 1; |
| } |
| |
| void xfrm_flush_all_bundles(void) |
| { |
| xfrm_prune_bundles(always_true); |
| } |
| |
| void xfrm_init_pmtu(struct dst_entry *dst) |
| { |
| do { |
| struct xfrm_dst *xdst = (struct xfrm_dst *)dst; |
| u32 pmtu, route_mtu_cached; |
| |
| pmtu = dst_mtu(dst->child); |
| 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->metrics[RTAX_MTU-1] = pmtu; |
| } while ((dst = dst->next)); |
| } |
| |
| EXPORT_SYMBOL(xfrm_init_pmtu); |
| |
| /* Check that the bundle accepts the flow and its components are |
| * still valid. |
| */ |
| |
| int xfrm_bundle_ok(struct xfrm_dst *first, struct flowi *fl, int family) |
| { |
| struct dst_entry *dst = &first->u.dst; |
| struct xfrm_dst *last; |
| u32 mtu; |
| |
| if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) || |
| (dst->dev && !netif_running(dst->dev))) |
| return 0; |
| |
| last = NULL; |
| |
| do { |
| struct xfrm_dst *xdst = (struct xfrm_dst *)dst; |
| |
| if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family)) |
| return 0; |
| if (dst->xfrm->km.state != XFRM_STATE_VALID) |
| return 0; |
| |
| mtu = dst_mtu(dst->child); |
| if (xdst->child_mtu_cached != mtu) { |
| last = xdst; |
| 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) { |
| last = xdst; |
| xdst->route_mtu_cached = mtu; |
| } |
| |
| dst = dst->child; |
| } while (dst->xfrm); |
| |
| if (likely(!last)) |
| return 1; |
| |
| mtu = last->child_mtu_cached; |
| for (;;) { |
| dst = &last->u.dst; |
| |
| mtu = xfrm_state_mtu(dst->xfrm, mtu); |
| if (mtu > last->route_mtu_cached) |
| mtu = last->route_mtu_cached; |
| dst->metrics[RTAX_MTU-1] = mtu; |
| |
| if (last == first) |
| break; |
| |
| last = last->u.next; |
| last->child_mtu_cached = mtu; |
| } |
| |
| return 1; |
| } |
| |
| EXPORT_SYMBOL(xfrm_bundle_ok); |
| |
| int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo) |
| { |
| int err = 0; |
| if (unlikely(afinfo == NULL)) |
| return -EINVAL; |
| if (unlikely(afinfo->family >= NPROTO)) |
| return -EAFNOSUPPORT; |
| write_lock(&xfrm_policy_afinfo_lock); |
| if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL)) |
| err = -ENOBUFS; |
| 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->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(afinfo->garbage_collect == NULL)) |
| afinfo->garbage_collect = __xfrm_garbage_collect; |
| xfrm_policy_afinfo[afinfo->family] = afinfo; |
| } |
| write_unlock(&xfrm_policy_afinfo_lock); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_policy_register_afinfo); |
| |
| int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo) |
| { |
| int err = 0; |
| if (unlikely(afinfo == NULL)) |
| return -EINVAL; |
| if (unlikely(afinfo->family >= NPROTO)) |
| return -EAFNOSUPPORT; |
| write_lock(&xfrm_policy_afinfo_lock); |
| if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) { |
| if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo)) |
| err = -EINVAL; |
| else { |
| struct dst_ops *dst_ops = afinfo->dst_ops; |
| xfrm_policy_afinfo[afinfo->family] = NULL; |
| dst_ops->kmem_cachep = NULL; |
| dst_ops->check = NULL; |
| dst_ops->negative_advice = NULL; |
| dst_ops->link_failure = NULL; |
| afinfo->garbage_collect = NULL; |
| } |
| } |
| write_unlock(&xfrm_policy_afinfo_lock); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_policy_unregister_afinfo); |
| |
| static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family) |
| { |
| struct xfrm_policy_afinfo *afinfo; |
| if (unlikely(family >= NPROTO)) |
| return NULL; |
| read_lock(&xfrm_policy_afinfo_lock); |
| afinfo = xfrm_policy_afinfo[family]; |
| if (likely(afinfo != NULL)) |
| read_lock(&afinfo->lock); |
| read_unlock(&xfrm_policy_afinfo_lock); |
| return afinfo; |
| } |
| |
| static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo) |
| { |
| if (unlikely(afinfo == NULL)) |
| return; |
| read_unlock(&afinfo->lock); |
| } |
| |
| static int xfrm_dev_event(struct notifier_block *this, unsigned long event, void *ptr) |
| { |
| switch (event) { |
| case NETDEV_DOWN: |
| xfrm_flush_bundles(); |
| } |
| return NOTIFY_DONE; |
| } |
| |
| static struct notifier_block xfrm_dev_notifier = { |
| xfrm_dev_event, |
| NULL, |
| 0 |
| }; |
| |
| static void __init xfrm_policy_init(void) |
| { |
| xfrm_dst_cache = kmem_cache_create("xfrm_dst_cache", |
| sizeof(struct xfrm_dst), |
| 0, SLAB_HWCACHE_ALIGN, |
| NULL, NULL); |
| if (!xfrm_dst_cache) |
| panic("XFRM: failed to allocate xfrm_dst_cache\n"); |
| |
| INIT_WORK(&xfrm_policy_gc_work, xfrm_policy_gc_task, NULL); |
| register_netdevice_notifier(&xfrm_dev_notifier); |
| } |
| |
| void __init xfrm_init(void) |
| { |
| xfrm_state_init(); |
| xfrm_policy_init(); |
| xfrm_input_init(); |
| } |
| |