From b2aa5e9d43a38dcdfa0878ed750cf32f98460278 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 13 Nov 2007 21:44:55 -0800 Subject: [PATCH] [IPSEC]: Store xfrm states in security path directly As it is xfrm_input first collects a list of xfrm states on the stack before storing them in the packet's security path just before it returns. For async crypto, this construction presents an obstacle since we may need to leave the loop after each transform. In fact, it's much easier to just skip the stack completely and always store to the security path. This is proven by the fact that this patch actually shrinks the code. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/xfrm/xfrm_input.c | 42 +++++++++++++++--------------------------- 1 file changed, 15 insertions(+), 27 deletions(-) diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c index b980095be935..587f3474ed3d 100644 --- a/net/xfrm/xfrm_input.c +++ b/net/xfrm/xfrm_input.c @@ -100,19 +100,29 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) { int err; __be32 seq; - struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH]; struct xfrm_state *x; - int xfrm_nr = 0; int decaps = 0; unsigned int nhoff = XFRM_SPI_SKB_CB(skb)->nhoff; unsigned int daddroff = XFRM_SPI_SKB_CB(skb)->daddroff; + /* Allocate new secpath or COW existing one. */ + if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { + struct sec_path *sp; + + sp = secpath_dup(skb->sp); + if (!sp) + goto drop; + if (skb->sp) + secpath_put(skb->sp); + skb->sp = sp; + } + seq = 0; if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) goto drop; do { - if (xfrm_nr == XFRM_MAX_DEPTH) + if (skb->sp->len == XFRM_MAX_DEPTH) goto drop; x = xfrm_state_lookup((xfrm_address_t *) @@ -121,6 +131,8 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) if (x == NULL) goto drop; + skb->sp->xvec[skb->sp->len++] = x; + spin_lock(&x->lock); if (unlikely(x->km.state != XFRM_STATE_VALID)) goto drop_unlock; @@ -151,8 +163,6 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) spin_unlock(&x->lock); - xfrm_vec[xfrm_nr++] = x; - if (x->inner_mode->input(x, skb)) goto drop; @@ -166,24 +176,6 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) goto drop; } while (!err); - /* Allocate new secpath or COW existing one. */ - - if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { - struct sec_path *sp; - sp = secpath_dup(skb->sp); - if (!sp) - goto drop; - if (skb->sp) - secpath_put(skb->sp); - skb->sp = sp; - } - if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH) - goto drop; - - memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec, - xfrm_nr * sizeof(xfrm_vec[0])); - skb->sp->len += xfrm_nr; - nf_reset(skb); if (decaps) { @@ -197,11 +189,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) drop_unlock: spin_unlock(&x->lock); - xfrm_state_put(x); drop: - while (--xfrm_nr >= 0) - xfrm_state_put(xfrm_vec[xfrm_nr]); - kfree_skb(skb); return 0; } -- 2.20.1