aboutsummaryrefslogtreecommitdiff
path: root/net/xfrm/xfrm_state.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/xfrm/xfrm_state.c')
-rw-r--r--net/xfrm/xfrm_state.c1037
1 files changed, 1037 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
new file mode 100644
index 00000000000..1db59f11f37
--- /dev/null
+++ b/net/xfrm/xfrm_state.c
@@ -0,0 +1,1037 @@
+/*
+ * xfrm_state.c
+ *
+ * Changes:
+ * Mitsuru KANDA @USAGI
+ * Kazunori MIYAZAWA @USAGI
+ * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
+ * IPv6 support
+ * YOSHIFUJI Hideaki @USAGI
+ * Split up af-specific functions
+ * Derek Atkins <derek@ihtfp.com>
+ * Add UDP Encapsulation
+ *
+ */
+
+#include <linux/workqueue.h>
+#include <net/xfrm.h>
+#include <linux/pfkeyv2.h>
+#include <linux/ipsec.h>
+#include <linux/module.h>
+#include <asm/uaccess.h>
+
+/* Each xfrm_state may be linked to two tables:
+
+ 1. Hash table by (spi,daddr,ah/esp) to find SA by SPI. (input,ctl)
+ 2. Hash table by daddr to find what SAs exist for given
+ destination/tunnel endpoint. (output)
+ */
+
+static DEFINE_SPINLOCK(xfrm_state_lock);
+
+/* Hash table to find appropriate SA towards given target (endpoint
+ * of tunnel or destination of transport mode) allowed by selector.
+ *
+ * Main use is finding SA after policy selected tunnel or transport mode.
+ * Also, it can be used by ah/esp icmp error handler to find offending SA.
+ */
+static struct list_head xfrm_state_bydst[XFRM_DST_HSIZE];
+static struct list_head xfrm_state_byspi[XFRM_DST_HSIZE];
+
+DECLARE_WAIT_QUEUE_HEAD(km_waitq);
+EXPORT_SYMBOL(km_waitq);
+
+static DEFINE_RWLOCK(xfrm_state_afinfo_lock);
+static struct xfrm_state_afinfo *xfrm_state_afinfo[NPROTO];
+
+static struct work_struct xfrm_state_gc_work;
+static struct list_head xfrm_state_gc_list = LIST_HEAD_INIT(xfrm_state_gc_list);
+static DEFINE_SPINLOCK(xfrm_state_gc_lock);
+
+static int xfrm_state_gc_flush_bundles;
+
+static void __xfrm_state_delete(struct xfrm_state *x);
+
+static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family);
+static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo);
+
+static int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol);
+static void km_state_expired(struct xfrm_state *x, int hard);
+
+static void xfrm_state_gc_destroy(struct xfrm_state *x)
+{
+ if (del_timer(&x->timer))
+ BUG();
+ if (x->aalg)
+ kfree(x->aalg);
+ if (x->ealg)
+ kfree(x->ealg);
+ if (x->calg)
+ kfree(x->calg);
+ if (x->encap)
+ kfree(x->encap);
+ if (x->type) {
+ x->type->destructor(x);
+ xfrm_put_type(x->type);
+ }
+ kfree(x);
+}
+
+static void xfrm_state_gc_task(void *data)
+{
+ struct xfrm_state *x;
+ struct list_head *entry, *tmp;
+ struct list_head gc_list = LIST_HEAD_INIT(gc_list);
+
+ if (xfrm_state_gc_flush_bundles) {
+ xfrm_state_gc_flush_bundles = 0;
+ xfrm_flush_bundles();
+ }
+
+ spin_lock_bh(&xfrm_state_gc_lock);
+ list_splice_init(&xfrm_state_gc_list, &gc_list);
+ spin_unlock_bh(&xfrm_state_gc_lock);
+
+ list_for_each_safe(entry, tmp, &gc_list) {
+ x = list_entry(entry, struct xfrm_state, bydst);
+ xfrm_state_gc_destroy(x);
+ }
+ wake_up(&km_waitq);
+}
+
+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_timer_handler(unsigned long data)
+{
+ struct xfrm_state *x = (struct xfrm_state*)data;
+ unsigned long now = (unsigned long)xtime.tv_sec;
+ long next = LONG_MAX;
+ int warn = 0;
+
+ spin_lock(&x->lock);
+ if (x->km.state == XFRM_STATE_DEAD)
+ goto out;
+ if (x->km.state == XFRM_STATE_EXPIRED)
+ goto expired;
+ if (x->lft.hard_add_expires_seconds) {
+ long tmo = x->lft.hard_add_expires_seconds +
+ x->curlft.add_time - now;
+ if (tmo <= 0)
+ goto expired;
+ if (tmo < next)
+ next = tmo;
+ }
+ if (x->lft.hard_use_expires_seconds) {
+ long tmo = x->lft.hard_use_expires_seconds +
+ (x->curlft.use_time ? : now) - now;
+ if (tmo <= 0)
+ goto expired;
+ if (tmo < next)
+ next = tmo;
+ }
+ if (x->km.dying)
+ goto resched;
+ if (x->lft.soft_add_expires_seconds) {
+ long tmo = x->lft.soft_add_expires_seconds +
+ x->curlft.add_time - now;
+ if (tmo <= 0)
+ warn = 1;
+ else if (tmo < next)
+ next = tmo;
+ }
+ if (x->lft.soft_use_expires_seconds) {
+ long tmo = x->lft.soft_use_expires_seconds +
+ (x->curlft.use_time ? : now) - now;
+ if (tmo <= 0)
+ warn = 1;
+ else if (tmo < next)
+ next = tmo;
+ }
+
+ if (warn)
+ km_state_expired(x, 0);
+resched:
+ if (next != LONG_MAX &&
+ !mod_timer(&x->timer, jiffies + make_jiffies(next)))
+ xfrm_state_hold(x);
+ goto out;
+
+expired:
+ if (x->km.state == XFRM_STATE_ACQ && x->id.spi == 0) {
+ x->km.state = XFRM_STATE_EXPIRED;
+ wake_up(&km_waitq);
+ next = 2;
+ goto resched;
+ }
+ if (x->id.spi != 0)
+ km_state_expired(x, 1);
+ __xfrm_state_delete(x);
+
+out:
+ spin_unlock(&x->lock);
+ xfrm_state_put(x);
+}
+
+struct xfrm_state *xfrm_state_alloc(void)
+{
+ struct xfrm_state *x;
+
+ x = kmalloc(sizeof(struct xfrm_state), GFP_ATOMIC);
+
+ if (x) {
+ memset(x, 0, sizeof(struct xfrm_state));
+ atomic_set(&x->refcnt, 1);
+ atomic_set(&x->tunnel_users, 0);
+ INIT_LIST_HEAD(&x->bydst);
+ INIT_LIST_HEAD(&x->byspi);
+ init_timer(&x->timer);
+ x->timer.function = xfrm_timer_handler;
+ x->timer.data = (unsigned long)x;
+ x->curlft.add_time = (unsigned long)xtime.tv_sec;
+ x->lft.soft_byte_limit = XFRM_INF;
+ x->lft.soft_packet_limit = XFRM_INF;
+ x->lft.hard_byte_limit = XFRM_INF;
+ x->lft.hard_packet_limit = XFRM_INF;
+ spin_lock_init(&x->lock);
+ }
+ return x;
+}
+EXPORT_SYMBOL(xfrm_state_alloc);
+
+void __xfrm_state_destroy(struct xfrm_state *x)
+{
+ BUG_TRAP(x->km.state == XFRM_STATE_DEAD);
+
+ spin_lock_bh(&xfrm_state_gc_lock);
+ list_add(&x->bydst, &xfrm_state_gc_list);
+ spin_unlock_bh(&xfrm_state_gc_lock);
+ schedule_work(&xfrm_state_gc_work);
+}
+EXPORT_SYMBOL(__xfrm_state_destroy);
+
+static void __xfrm_state_delete(struct xfrm_state *x)
+{
+ if (x->km.state != XFRM_STATE_DEAD) {
+ x->km.state = XFRM_STATE_DEAD;
+ spin_lock(&xfrm_state_lock);
+ list_del(&x->bydst);
+ atomic_dec(&x->refcnt);
+ if (x->id.spi) {
+ list_del(&x->byspi);
+ atomic_dec(&x->refcnt);
+ }
+ spin_unlock(&xfrm_state_lock);
+ if (del_timer(&x->timer))
+ atomic_dec(&x->refcnt);
+
+ /* The number two in this test is the reference
+ * mentioned in the comment below plus the reference
+ * our caller holds. A larger value means that
+ * there are DSTs attached to this xfrm_state.
+ */
+ if (atomic_read(&x->refcnt) > 2) {
+ xfrm_state_gc_flush_bundles = 1;
+ schedule_work(&xfrm_state_gc_work);
+ }
+
+ /* All xfrm_state objects are created by xfrm_state_alloc.
+ * The xfrm_state_alloc call gives a reference, and that
+ * is what we are dropping here.
+ */
+ atomic_dec(&x->refcnt);
+ }
+}
+
+void xfrm_state_delete(struct xfrm_state *x)
+{
+ spin_lock_bh(&x->lock);
+ __xfrm_state_delete(x);
+ spin_unlock_bh(&x->lock);
+}
+EXPORT_SYMBOL(xfrm_state_delete);
+
+void xfrm_state_flush(u8 proto)
+{
+ int i;
+ struct xfrm_state *x;
+
+ spin_lock_bh(&xfrm_state_lock);
+ for (i = 0; i < XFRM_DST_HSIZE; i++) {
+restart:
+ list_for_each_entry(x, xfrm_state_bydst+i, bydst) {
+ if (!xfrm_state_kern(x) &&
+ (proto == IPSEC_PROTO_ANY || x->id.proto == proto)) {
+ xfrm_state_hold(x);
+ spin_unlock_bh(&xfrm_state_lock);
+
+ xfrm_state_delete(x);
+ xfrm_state_put(x);
+
+ spin_lock_bh(&xfrm_state_lock);
+ goto restart;
+ }
+ }
+ }
+ spin_unlock_bh(&xfrm_state_lock);
+ wake_up(&km_waitq);
+}
+EXPORT_SYMBOL(xfrm_state_flush);
+
+static int
+xfrm_init_tempsel(struct xfrm_state *x, struct flowi *fl,
+ struct xfrm_tmpl *tmpl,
+ xfrm_address_t *daddr, xfrm_address_t *saddr,
+ unsigned short family)
+{
+ struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family);
+ if (!afinfo)
+ return -1;
+ afinfo->init_tempsel(x, fl, tmpl, daddr, saddr);
+ xfrm_state_put_afinfo(afinfo);
+ return 0;
+}
+
+struct xfrm_state *
+xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
+ struct flowi *fl, struct xfrm_tmpl *tmpl,
+ struct xfrm_policy *pol, int *err,
+ unsigned short family)
+{
+ unsigned h = xfrm_dst_hash(daddr, family);
+ struct xfrm_state *x, *x0;
+ int acquire_in_progress = 0;
+ int error = 0;
+ struct xfrm_state *best = NULL;
+ struct xfrm_state_afinfo *afinfo;
+
+ afinfo = xfrm_state_get_afinfo(family);
+ if (afinfo == NULL) {
+ *err = -EAFNOSUPPORT;
+ return NULL;
+ }
+
+ spin_lock_bh(&xfrm_state_lock);
+ list_for_each_entry(x, xfrm_state_bydst+h, bydst) {
+ if (x->props.family == family &&
+ x->props.reqid == tmpl->reqid &&
+ xfrm_state_addr_check(x, daddr, saddr, family) &&
+ tmpl->mode == x->props.mode &&
+ tmpl->id.proto == x->id.proto &&
+ (tmpl->id.spi == x->id.spi || !tmpl->id.spi)) {
+ /* Resolution logic:
+ 1. There is a valid state with matching selector.
+ Done.
+ 2. Valid state with inappropriate selector. Skip.
+
+ Entering area of "sysdeps".
+
+ 3. If state is not valid, selector is temporary,
+ it selects only session which triggered
+ previous resolution. Key manager will do
+ something to install a state with proper
+ selector.
+ */
+ if (x->km.state == XFRM_STATE_VALID) {
+ if (!xfrm_selector_match(&x->sel, fl, family))
+ continue;
+ if (!best ||
+ best->km.dying > x->km.dying ||
+ (best->km.dying == x->km.dying &&
+ best->curlft.add_time < x->curlft.add_time))
+ best = x;
+ } else if (x->km.state == XFRM_STATE_ACQ) {
+ acquire_in_progress = 1;
+ } else if (x->km.state == XFRM_STATE_ERROR ||
+ x->km.state == XFRM_STATE_EXPIRED) {
+ if (xfrm_selector_match(&x->sel, fl, family))
+ error = -ESRCH;
+ }
+ }
+ }
+
+ x = best;
+ if (!x && !error && !acquire_in_progress) {
+ x0 = afinfo->state_lookup(&tmpl->id.daddr, tmpl->id.spi, tmpl->id.proto);
+ if (x0 != NULL) {
+ xfrm_state_put(x0);
+ error = -EEXIST;
+ goto out;
+ }
+ x = xfrm_state_alloc();
+ if (x == NULL) {
+ error = -ENOMEM;
+ goto out;
+ }
+ /* Initialize temporary selector matching only
+ * to current session. */
+ xfrm_init_tempsel(x, fl, tmpl, daddr, saddr, family);
+
+ if (km_query(x, tmpl, pol) == 0) {
+ x->km.state = XFRM_STATE_ACQ;
+ list_add_tail(&x->bydst, xfrm_state_bydst+h);
+ xfrm_state_hold(x);
+ if (x->id.spi) {
+ h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, family);
+ list_add(&x->byspi, xfrm_state_byspi+h);
+ xfrm_state_hold(x);
+ }
+ x->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES;
+ xfrm_state_hold(x);
+ x->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ;
+ add_timer(&x->timer);
+ } else {
+ x->km.state = XFRM_STATE_DEAD;
+ xfrm_state_put(x);
+ x = NULL;
+ error = -ESRCH;
+ }
+ }
+out:
+ if (x)
+ xfrm_state_hold(x);
+ else
+ *err = acquire_in_progress ? -EAGAIN : error;
+ spin_unlock_bh(&xfrm_state_lock);
+ xfrm_state_put_afinfo(afinfo);
+ return x;
+}
+
+static void __xfrm_state_insert(struct xfrm_state *x)
+{
+ unsigned h = xfrm_dst_hash(&x->id.daddr, x->props.family);
+
+ list_add(&x->bydst, xfrm_state_bydst+h);
+ xfrm_state_hold(x);
+
+ h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, x->props.family);
+
+ list_add(&x->byspi, xfrm_state_byspi+h);
+ xfrm_state_hold(x);
+
+ if (!mod_timer(&x->timer, jiffies + HZ))
+ xfrm_state_hold(x);
+
+ wake_up(&km_waitq);
+}
+
+void xfrm_state_insert(struct xfrm_state *x)
+{
+ spin_lock_bh(&xfrm_state_lock);
+ __xfrm_state_insert(x);
+ spin_unlock_bh(&xfrm_state_lock);
+}
+EXPORT_SYMBOL(xfrm_state_insert);
+
+static struct xfrm_state *__xfrm_find_acq_byseq(u32 seq);
+
+int xfrm_state_add(struct xfrm_state *x)
+{
+ struct xfrm_state_afinfo *afinfo;
+ struct xfrm_state *x1;
+ int family;
+ int err;
+
+ family = x->props.family;
+ afinfo = xfrm_state_get_afinfo(family);
+ if (unlikely(afinfo == NULL))
+ return -EAFNOSUPPORT;
+
+ spin_lock_bh(&xfrm_state_lock);
+
+ x1 = afinfo->state_lookup(&x->id.daddr, x->id.spi, x->id.proto);
+ if (x1) {
+ xfrm_state_put(x1);
+ x1 = NULL;
+ err = -EEXIST;
+ goto out;
+ }
+
+ if (x->km.seq) {
+ x1 = __xfrm_find_acq_byseq(x->km.seq);
+ if (x1 && xfrm_addr_cmp(&x1->id.daddr, &x->id.daddr, family)) {
+ xfrm_state_put(x1);
+ x1 = NULL;
+ }
+ }
+
+ if (!x1)
+ x1 = afinfo->find_acq(
+ x->props.mode, x->props.reqid, x->id.proto,
+ &x->id.daddr, &x->props.saddr, 0);
+
+ __xfrm_state_insert(x);
+ err = 0;
+
+out:
+ spin_unlock_bh(&xfrm_state_lock);
+ xfrm_state_put_afinfo(afinfo);
+
+ if (x1) {
+ xfrm_state_delete(x1);
+ xfrm_state_put(x1);
+ }
+
+ return err;
+}
+EXPORT_SYMBOL(xfrm_state_add);
+
+int xfrm_state_update(struct xfrm_state *x)
+{
+ struct xfrm_state_afinfo *afinfo;
+ struct xfrm_state *x1;
+ int err;
+
+ afinfo = xfrm_state_get_afinfo(x->props.family);
+ if (unlikely(afinfo == NULL))
+ return -EAFNOSUPPORT;
+
+ spin_lock_bh(&xfrm_state_lock);
+ x1 = afinfo->state_lookup(&x->id.daddr, x->id.spi, x->id.proto);
+
+ err = -ESRCH;
+ if (!x1)
+ goto out;
+
+ if (xfrm_state_kern(x1)) {
+ xfrm_state_put(x1);
+ err = -EEXIST;
+ goto out;
+ }
+
+ if (x1->km.state == XFRM_STATE_ACQ) {
+ __xfrm_state_insert(x);
+ x = NULL;
+ }
+ err = 0;
+
+out:
+ spin_unlock_bh(&xfrm_state_lock);
+ xfrm_state_put_afinfo(afinfo);
+
+ if (err)
+ return err;
+
+ if (!x) {
+ xfrm_state_delete(x1);
+ xfrm_state_put(x1);
+ return 0;
+ }
+
+ err = -EINVAL;
+ spin_lock_bh(&x1->lock);
+ if (likely(x1->km.state == XFRM_STATE_VALID)) {
+ if (x->encap && x1->encap)
+ memcpy(x1->encap, x->encap, sizeof(*x1->encap));
+ memcpy(&x1->lft, &x->lft, sizeof(x1->lft));
+ x1->km.dying = 0;
+
+ if (!mod_timer(&x1->timer, jiffies + HZ))
+ xfrm_state_hold(x1);
+ if (x1->curlft.use_time)
+ xfrm_state_check_expire(x1);
+
+ err = 0;
+ }
+ spin_unlock_bh(&x1->lock);
+
+ xfrm_state_put(x1);
+
+ return err;
+}
+EXPORT_SYMBOL(xfrm_state_update);
+
+int xfrm_state_check_expire(struct xfrm_state *x)
+{
+ if (!x->curlft.use_time)
+ x->curlft.use_time = (unsigned long)xtime.tv_sec;
+
+ if (x->km.state != XFRM_STATE_VALID)
+ return -EINVAL;
+
+ if (x->curlft.bytes >= x->lft.hard_byte_limit ||
+ x->curlft.packets >= x->lft.hard_packet_limit) {
+ km_state_expired(x, 1);
+ if (!mod_timer(&x->timer, jiffies + XFRM_ACQ_EXPIRES*HZ))
+ xfrm_state_hold(x);
+ return -EINVAL;
+ }
+
+ if (!x->km.dying &&
+ (x->curlft.bytes >= x->lft.soft_byte_limit ||
+ x->curlft.packets >= x->lft.soft_packet_limit))
+ km_state_expired(x, 0);
+ return 0;
+}
+EXPORT_SYMBOL(xfrm_state_check_expire);
+
+static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb)
+{
+ int nhead = x->props.header_len + LL_RESERVED_SPACE(skb->dst->dev)
+ - skb_headroom(skb);
+
+ if (nhead > 0)
+ return pskb_expand_head(skb, nhead, 0, GFP_ATOMIC);
+
+ /* Check tail too... */
+ return 0;
+}
+
+int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb)
+{
+ int err = xfrm_state_check_expire(x);
+ if (err < 0)
+ goto err;
+ err = xfrm_state_check_space(x, skb);
+err:
+ return err;
+}
+EXPORT_SYMBOL(xfrm_state_check);
+
+struct xfrm_state *
+xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto,
+ unsigned short family)
+{
+ struct xfrm_state *x;
+ struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family);
+ if (!afinfo)
+ return NULL;
+
+ spin_lock_bh(&xfrm_state_lock);
+ x = afinfo->state_lookup(daddr, spi, proto);
+ spin_unlock_bh(&xfrm_state_lock);
+ xfrm_state_put_afinfo(afinfo);
+ return x;
+}
+EXPORT_SYMBOL(xfrm_state_lookup);
+
+struct xfrm_state *
+xfrm_find_acq(u8 mode, u32 reqid, u8 proto,
+ xfrm_address_t *daddr, xfrm_address_t *saddr,
+ int create, unsigned short family)
+{
+ struct xfrm_state *x;
+ struct xfrm_state_afinfo *afinfo = xfrm_state_get_afinfo(family);
+ if (!afinfo)
+ return NULL;
+
+ spin_lock_bh(&xfrm_state_lock);
+ x = afinfo->find_acq(mode, reqid, proto, daddr, saddr, create);
+ spin_unlock_bh(&xfrm_state_lock);
+ xfrm_state_put_afinfo(afinfo);
+ return x;
+}
+EXPORT_SYMBOL(xfrm_find_acq);
+
+/* Silly enough, but I'm lazy to build resolution list */
+
+static struct xfrm_state *__xfrm_find_acq_byseq(u32 seq)
+{
+ int i;
+ struct xfrm_state *x;
+
+ for (i = 0; i < XFRM_DST_HSIZE; i++) {
+ list_for_each_entry(x, xfrm_state_bydst+i, bydst) {
+ if (x->km.seq == seq && x->km.state == XFRM_STATE_ACQ) {
+ xfrm_state_hold(x);
+ return x;
+ }
+ }
+ }
+ return NULL;
+}
+
+struct xfrm_state *xfrm_find_acq_byseq(u32 seq)
+{
+ struct xfrm_state *x;
+
+ spin_lock_bh(&xfrm_state_lock);
+ x = __xfrm_find_acq_byseq(seq);
+ spin_unlock_bh(&xfrm_state_lock);
+ return x;
+}
+EXPORT_SYMBOL(xfrm_find_acq_byseq);
+
+u32 xfrm_get_acqseq(void)
+{
+ u32 res;
+ static u32 acqseq;
+ static DEFINE_SPINLOCK(acqseq_lock);
+
+ spin_lock_bh(&acqseq_lock);
+ res = (++acqseq ? : ++acqseq);
+ spin_unlock_bh(&acqseq_lock);
+ return res;
+}
+EXPORT_SYMBOL(xfrm_get_acqseq);
+
+void
+xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi)
+{
+ u32 h;
+ struct xfrm_state *x0;
+
+ if (x->id.spi)
+ return;
+
+ if (minspi == maxspi) {
+ x0 = xfrm_state_lookup(&x->id.daddr, minspi, x->id.proto, x->props.family);
+ if (x0) {
+ xfrm_state_put(x0);
+ return;
+ }
+ x->id.spi = minspi;
+ } else {
+ u32 spi = 0;
+ minspi = ntohl(minspi);
+ maxspi = ntohl(maxspi);
+ for (h=0; h<maxspi-minspi+1; h++) {
+ spi = minspi + net_random()%(maxspi-minspi+1);
+ x0 = xfrm_state_lookup(&x->id.daddr, htonl(spi), x->id.proto, x->props.family);
+ if (x0 == NULL) {
+ x->id.spi = htonl(spi);
+ break;
+ }
+ xfrm_state_put(x0);
+ }
+ }
+ if (x->id.spi) {
+ spin_lock_bh(&xfrm_state_lock);
+ h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, x->props.family);
+ list_add(&x->byspi, xfrm_state_byspi+h);
+ xfrm_state_hold(x);
+ spin_unlock_bh(&xfrm_state_lock);
+ wake_up(&km_waitq);
+ }
+}
+EXPORT_SYMBOL(xfrm_alloc_spi);
+
+int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*),
+ void *data)
+{
+ int i;
+ struct xfrm_state *x;
+ int count = 0;
+ int err = 0;
+
+ spin_lock_bh(&xfrm_state_lock);
+ for (i = 0; i < XFRM_DST_HSIZE; i++) {
+ list_for_each_entry(x, xfrm_state_bydst+i, bydst) {
+ if (proto == IPSEC_PROTO_ANY || x->id.proto == proto)
+ count++;
+ }
+ }
+ if (count == 0) {
+ err = -ENOENT;
+ goto out;
+ }
+
+ for (i = 0; i < XFRM_DST_HSIZE; i++) {
+ list_for_each_entry(x, xfrm_state_bydst+i, bydst) {
+ if (proto != IPSEC_PROTO_ANY && x->id.proto != proto)
+ continue;
+ err = func(x, --count, data);
+ if (err)
+ goto out;
+ }
+ }
+out:
+ spin_unlock_bh(&xfrm_state_lock);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_state_walk);
+
+int xfrm_replay_check(struct xfrm_state *x, u32 seq)
+{
+ u32 diff;
+
+ seq = ntohl(seq);
+
+ if (unlikely(seq == 0))
+ return -EINVAL;
+
+ if (likely(seq > x->replay.seq))
+ return 0;
+
+ diff = x->replay.seq - seq;
+ if (diff >= x->props.replay_window) {
+ x->stats.replay_window++;
+ return -EINVAL;
+ }
+
+ if (x->replay.bitmap & (1U << diff)) {
+ x->stats.replay++;
+ return -EINVAL;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(xfrm_replay_check);
+
+void xfrm_replay_advance(struct xfrm_state *x, u32 seq)
+{
+ u32 diff;
+
+ seq = ntohl(seq);
+
+ if (seq > x->replay.seq) {
+ diff = seq - x->replay.seq;
+ if (diff < x->props.replay_window)
+ x->replay.bitmap = ((x->replay.bitmap) << diff) | 1;
+ else
+ x->replay.bitmap = 1;
+ x->replay.seq = seq;
+ } else {
+ diff = x->replay.seq - seq;
+ x->replay.bitmap |= (1U << diff);
+ }
+}
+EXPORT_SYMBOL(xfrm_replay_advance);
+
+static struct list_head xfrm_km_list = LIST_HEAD_INIT(xfrm_km_list);
+static DEFINE_RWLOCK(xfrm_km_lock);
+
+static void km_state_expired(struct xfrm_state *x, int hard)
+{
+ struct xfrm_mgr *km;
+
+ if (hard)
+ x->km.state = XFRM_STATE_EXPIRED;
+ else
+ x->km.dying = 1;
+
+ read_lock(&xfrm_km_lock);
+ list_for_each_entry(km, &xfrm_km_list, list)
+ km->notify(x, hard);
+ read_unlock(&xfrm_km_lock);
+
+ if (hard)
+ wake_up(&km_waitq);
+}
+
+static int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol)
+{
+ int err = -EINVAL;
+ struct xfrm_mgr *km;
+
+ read_lock(&xfrm_km_lock);
+ list_for_each_entry(km, &xfrm_km_list, list) {
+ err = km->acquire(x, t, pol, XFRM_POLICY_OUT);
+ if (!err)
+ break;
+ }
+ read_unlock(&xfrm_km_lock);
+ return err;
+}
+
+int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport)
+{
+ int err = -EINVAL;
+ struct xfrm_mgr *km;
+
+ read_lock(&xfrm_km_lock);
+ list_for_each_entry(km, &xfrm_km_list, list) {
+ if (km->new_mapping)
+ err = km->new_mapping(x, ipaddr, sport);
+ if (!err)
+ break;
+ }
+ read_unlock(&xfrm_km_lock);
+ return err;
+}
+EXPORT_SYMBOL(km_new_mapping);
+
+void km_policy_expired(struct xfrm_policy *pol, int dir, int hard)
+{
+ struct xfrm_mgr *km;
+
+ read_lock(&xfrm_km_lock);
+ list_for_each_entry(km, &xfrm_km_list, list)
+ if (km->notify_policy)
+ km->notify_policy(pol, dir, hard);
+ read_unlock(&xfrm_km_lock);
+
+ if (hard)
+ wake_up(&km_waitq);
+}
+
+int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
+{
+ int err;
+ u8 *data;
+ struct xfrm_mgr *km;
+ struct xfrm_policy *pol = NULL;
+
+ if (optlen <= 0 || optlen > PAGE_SIZE)
+ return -EMSGSIZE;
+
+ data = kmalloc(optlen, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ err = -EFAULT;
+ if (copy_from_user(data, optval, optlen))
+ goto out;
+
+ err = -EINVAL;
+ read_lock(&xfrm_km_lock);
+ list_for_each_entry(km, &xfrm_km_list, list) {
+ pol = km->compile_policy(sk->sk_family, optname, data,
+ optlen, &err);
+ if (err >= 0)
+ break;
+ }
+ read_unlock(&xfrm_km_lock);
+
+ if (err >= 0) {
+ xfrm_sk_policy_insert(sk, err, pol);
+ xfrm_pol_put(pol);
+ err = 0;
+ }
+
+out:
+ kfree(data);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_user_policy);
+
+int xfrm_register_km(struct xfrm_mgr *km)
+{
+ write_lock_bh(&xfrm_km_lock);
+ list_add_tail(&km->list, &xfrm_km_list);
+ write_unlock_bh(&xfrm_km_lock);
+ return 0;
+}
+EXPORT_SYMBOL(xfrm_register_km);
+
+int xfrm_unregister_km(struct xfrm_mgr *km)
+{
+ write_lock_bh(&xfrm_km_lock);
+ list_del(&km->list);
+ write_unlock_bh(&xfrm_km_lock);
+ return 0;
+}
+EXPORT_SYMBOL(xfrm_unregister_km);
+
+int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo)
+{
+ int err = 0;
+ if (unlikely(afinfo == NULL))
+ return -EINVAL;
+ if (unlikely(afinfo->family >= NPROTO))
+ return -EAFNOSUPPORT;
+ write_lock(&xfrm_state_afinfo_lock);
+ if (unlikely(xfrm_state_afinfo[afinfo->family] != NULL))
+ err = -ENOBUFS;
+ else {
+ afinfo->state_bydst = xfrm_state_bydst;
+ afinfo->state_byspi = xfrm_state_byspi;
+ xfrm_state_afinfo[afinfo->family] = afinfo;
+ }
+ write_unlock(&xfrm_state_afinfo_lock);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_state_register_afinfo);
+
+int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo)
+{
+ int err = 0;
+ if (unlikely(afinfo == NULL))
+ return -EINVAL;
+ if (unlikely(afinfo->family >= NPROTO))
+ return -EAFNOSUPPORT;
+ write_lock(&xfrm_state_afinfo_lock);
+ if (likely(xfrm_state_afinfo[afinfo->family] != NULL)) {
+ if (unlikely(xfrm_state_afinfo[afinfo->family] != afinfo))
+ err = -EINVAL;
+ else {
+ xfrm_state_afinfo[afinfo->family] = NULL;
+ afinfo->state_byspi = NULL;
+ afinfo->state_bydst = NULL;
+ }
+ }
+ write_unlock(&xfrm_state_afinfo_lock);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_state_unregister_afinfo);
+
+static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family)
+{
+ struct xfrm_state_afinfo *afinfo;
+ if (unlikely(family >= NPROTO))
+ return NULL;
+ read_lock(&xfrm_state_afinfo_lock);
+ afinfo = xfrm_state_afinfo[family];
+ if (likely(afinfo != NULL))
+ read_lock(&afinfo->lock);
+ read_unlock(&xfrm_state_afinfo_lock);
+ return afinfo;
+}
+
+static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo)
+{
+ if (unlikely(afinfo == NULL))
+ return;
+ read_unlock(&afinfo->lock);
+}
+
+/* Temporarily located here until net/xfrm/xfrm_tunnel.c is created */
+void xfrm_state_delete_tunnel(struct xfrm_state *x)
+{
+ if (x->tunnel) {
+ struct xfrm_state *t = x->tunnel;
+
+ if (atomic_read(&t->tunnel_users) == 2)
+ xfrm_state_delete(t);
+ atomic_dec(&t->tunnel_users);
+ xfrm_state_put(t);
+ x->tunnel = NULL;
+ }
+}
+EXPORT_SYMBOL(xfrm_state_delete_tunnel);
+
+int xfrm_state_mtu(struct xfrm_state *x, int mtu)
+{
+ int res = mtu;
+
+ res -= x->props.header_len;
+
+ for (;;) {
+ int m = res;
+
+ if (m < 68)
+ return 68;
+
+ spin_lock_bh(&x->lock);
+ if (x->km.state == XFRM_STATE_VALID &&
+ x->type && x->type->get_max_size)
+ m = x->type->get_max_size(x, m);
+ else
+ m += x->props.header_len;
+ spin_unlock_bh(&x->lock);
+
+ if (m <= mtu)
+ break;
+ res -= (m - mtu);
+ }
+
+ return res;
+}
+
+EXPORT_SYMBOL(xfrm_state_mtu);
+
+void __init xfrm_state_init(void)
+{
+ int i;
+
+ for (i=0; i<XFRM_DST_HSIZE; i++) {
+ INIT_LIST_HEAD(&xfrm_state_bydst[i]);
+ INIT_LIST_HEAD(&xfrm_state_byspi[i]);
+ }
+ INIT_WORK(&xfrm_state_gc_work, xfrm_state_gc_task, NULL);
+}
+