xfrm: Move IPsec replay detection functions to a separate file

To support multiple versions of replay detection, we move the replay
detection functions to a separate file and make them accessible
via function pointers contained in the struct xfrm_replay.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 108 deletions

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index cd6be49f2ae..23779d19fe0 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -42,13 +42,6 @@ static unsigned int xfrm_state_hashmax __read_mostly = 1 * 1024 * 1024;
 static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned int family);
 static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo);
 
-#ifdef CONFIG_AUDITSYSCALL
-static void xfrm_audit_state_replay(struct xfrm_state *x,
-				    struct sk_buff *skb, __be32 net_seq);
-#else
-#define xfrm_audit_state_replay(x, s, sq)	do { ; } while (0)
-#endif /* CONFIG_AUDITSYSCALL */
-
 static inline unsigned int xfrm_dst_hash(struct net *net,
 					 const xfrm_address_t *daddr,
 					 const xfrm_address_t *saddr,
@@ -1619,54 +1612,6 @@ void xfrm_state_walk_done(struct xfrm_state_walk *walk)
 }
 EXPORT_SYMBOL(xfrm_state_walk_done);
 
-
-void xfrm_replay_notify(struct xfrm_state *x, int event)
-{
-	struct km_event c;
-	/* we send notify messages in case
-	 *  1. we updated on of the sequence numbers, and the seqno difference
-	 *     is at least x->replay_maxdiff, in this case we also update the
-	 *     timeout of our timer function
-	 *  2. if x->replay_maxage has elapsed since last update,
-	 *     and there were changes
-	 *
-	 *  The state structure must be locked!
-	 */
-
-	switch (event) {
-	case XFRM_REPLAY_UPDATE:
-		if (x->replay_maxdiff &&
-		    (x->replay.seq - x->preplay.seq < x->replay_maxdiff) &&
-		    (x->replay.oseq - x->preplay.oseq < x->replay_maxdiff)) {
-			if (x->xflags & XFRM_TIME_DEFER)
-				event = XFRM_REPLAY_TIMEOUT;
-			else
-				return;
-		}
-
-		break;
-
-	case XFRM_REPLAY_TIMEOUT:
-		if ((x->replay.seq == x->preplay.seq) &&
-		    (x->replay.bitmap == x->preplay.bitmap) &&
-		    (x->replay.oseq == x->preplay.oseq)) {
-			x->xflags |= XFRM_TIME_DEFER;
-			return;
-		}
-
-		break;
-	}
-
-	memcpy(&x->preplay, &x->replay, sizeof(struct xfrm_replay_state));
-	c.event = XFRM_MSG_NEWAE;
-	c.data.aevent = event;
-	km_state_notify(x, &c);
-
-	if (x->replay_maxage &&
-	    !mod_timer(&x->rtimer, jiffies + x->replay_maxage))
-		x->xflags &= ~XFRM_TIME_DEFER;
-}
-
 static void xfrm_replay_timer_handler(unsigned long data)
 {
 	struct xfrm_state *x = (struct xfrm_state*)data;
@@ -1675,7 +1620,7 @@ static void xfrm_replay_timer_handler(unsigned long data)
 
 	if (x->km.state == XFRM_STATE_VALID) {
 		if (xfrm_aevent_is_on(xs_net(x)))
-			xfrm_replay_notify(x, XFRM_REPLAY_TIMEOUT);
+			x->repl->notify(x, XFRM_REPLAY_TIMEOUT);
 		else
 			x->xflags |= XFRM_TIME_DEFER;
 	}
@@ -1683,57 +1628,6 @@ static void xfrm_replay_timer_handler(unsigned long data)
 	spin_unlock(&x->lock);
 }
 
-int xfrm_replay_check(struct xfrm_state *x,
-		      struct sk_buff *skb, __be32 net_seq)
-{
-	u32 diff;
-	u32 seq = ntohl(net_seq);
-
-	if (unlikely(seq == 0))
-		goto err;
-
-	if (likely(seq > x->replay.seq))
-		return 0;
-
-	diff = x->replay.seq - seq;
-	if (diff >= min_t(unsigned int, x->props.replay_window,
-			  sizeof(x->replay.bitmap) * 8)) {
-		x->stats.replay_window++;
-		goto err;
-	}
-
-	if (x->replay.bitmap & (1U << diff)) {
-		x->stats.replay++;
-		goto err;
-	}
-	return 0;
-
-err:
-	xfrm_audit_state_replay(x, skb, net_seq);
-	return -EINVAL;
-}
-
-void xfrm_replay_advance(struct xfrm_state *x, __be32 net_seq)
-{
-	u32 diff;
-	u32 seq = ntohl(net_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);
-	}
-
-	if (xfrm_aevent_is_on(xs_net(x)))
-		xfrm_replay_notify(x, XFRM_REPLAY_UPDATE);
-}
-
 static LIST_HEAD(xfrm_km_list);
 static DEFINE_RWLOCK(xfrm_km_lock);
 
@@ -2246,7 +2140,7 @@ void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 }
 EXPORT_SYMBOL_GPL(xfrm_audit_state_replay_overflow);
 
-static void xfrm_audit_state_replay(struct xfrm_state *x,
+void xfrm_audit_state_replay(struct xfrm_state *x,
 			     struct sk_buff *skb, __be32 net_seq)
 {
 	struct audit_buffer *audit_buf;
@@ -2261,6 +2155,7 @@ static void xfrm_audit_state_replay(struct xfrm_state *x,
 			 spi, spi, ntohl(net_seq));
 	audit_log_end(audit_buf);
 }
+EXPORT_SYMBOL_GPL(xfrm_audit_state_replay);
 
 void xfrm_audit_state_notfound_simple(struct sk_buff *skb, u16 family)
 {