From 707a2ca4870fcf6b5480cdfad563b940f56f0844 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Tue, 7 Jun 2016 16:09:44 -0700 Subject: [PATCH] ila: Perform only one translation in forwarding path When setting up ILA in a router we noticed that the the encapsulation is invoked twice: once in the route input path and again upon route output. To resolve this we add a flag set_csum_neutral for the ila_update_ipv6_locator. If this flag is set and the checksum neutral bit is also set we assume that checksum-neutral translation has already been performed and take no further action. The flag is set only in ila_output path. The flag is not set for ila_input and ila_xlat. Tested: Used 3 netns to set to emulate a router and two hosts. The router translates SIR addresses between the two destinations in other two netns. Verified ping and netperf are functional. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- net/ipv6/ila/ila.h | 3 ++- net/ipv6/ila/ila_common.c | 6 ++++-- net/ipv6/ila/ila_lwt.c | 4 ++-- net/ipv6/ila/ila_xlat.c | 8 ++++---- 4 files changed, 12 insertions(+), 9 deletions(-) diff --git a/net/ipv6/ila/ila.h b/net/ipv6/ila/ila.h index d08fd2d48a78..e0170f62bc39 100644 --- a/net/ipv6/ila/ila.h +++ b/net/ipv6/ila/ila.h @@ -109,7 +109,8 @@ static inline bool ila_csum_neutral_set(struct ila_identifier ident) return !!(ident.csum_neutral); } -void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p); +void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p, + bool set_csum_neutral); void ila_init_saved_csum(struct ila_params *p); diff --git a/net/ipv6/ila/ila_common.c b/net/ipv6/ila/ila_common.c index 0e94042d1289..b3d00be484d4 100644 --- a/net/ipv6/ila/ila_common.c +++ b/net/ipv6/ila/ila_common.c @@ -103,7 +103,8 @@ static void ila_csum_adjust_transport(struct sk_buff *skb, iaddr->loc = p->locator; } -void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p) +void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p, + bool set_csum_neutral) { struct ipv6hdr *ip6h = ipv6_hdr(skb); struct ila_addr *iaddr = ila_a2i(&ip6h->daddr); @@ -114,7 +115,8 @@ void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p) * is a locator being translated to a SIR address. * Perform (receiver) checksum-neutral translation. */ - ila_csum_do_neutral(iaddr, p); + if (!set_csum_neutral) + ila_csum_do_neutral(iaddr, p); } else { switch (p->csum_mode) { case ILA_CSUM_ADJUST_TRANSPORT: diff --git a/net/ipv6/ila/ila_lwt.c b/net/ipv6/ila/ila_lwt.c index 1dfb64166d7d..c8314c6b6154 100644 --- a/net/ipv6/ila/ila_lwt.c +++ b/net/ipv6/ila/ila_lwt.c @@ -26,7 +26,7 @@ static int ila_output(struct net *net, struct sock *sk, struct sk_buff *skb) if (skb->protocol != htons(ETH_P_IPV6)) goto drop; - ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate)); + ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate), true); return dst->lwtstate->orig_output(net, sk, skb); @@ -42,7 +42,7 @@ static int ila_input(struct sk_buff *skb) if (skb->protocol != htons(ETH_P_IPV6)) goto drop; - ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate)); + ila_update_ipv6_locator(skb, ila_params_lwtunnel(dst->lwtstate), false); return dst->lwtstate->orig_input(skb); diff --git a/net/ipv6/ila/ila_xlat.c b/net/ipv6/ila/ila_xlat.c index a90e57229c6c..e6eca5fdf4c9 100644 --- a/net/ipv6/ila/ila_xlat.c +++ b/net/ipv6/ila/ila_xlat.c @@ -210,14 +210,14 @@ static void ila_free_cb(void *ptr, void *arg) } } -static int ila_xlat_addr(struct sk_buff *skb); +static int ila_xlat_addr(struct sk_buff *skb, bool set_csum_neutral); static unsigned int ila_nf_input(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) { - ila_xlat_addr(skb); + ila_xlat_addr(skb, false); return NF_ACCEPT; } @@ -597,7 +597,7 @@ static struct pernet_operations ila_net_ops = { .size = sizeof(struct ila_net), }; -static int ila_xlat_addr(struct sk_buff *skb) +static int ila_xlat_addr(struct sk_buff *skb, bool set_csum_neutral) { struct ila_map *ila; struct ipv6hdr *ip6h = ipv6_hdr(skb); @@ -616,7 +616,7 @@ static int ila_xlat_addr(struct sk_buff *skb) ila = ila_lookup_wildcards(iaddr, skb->dev->ifindex, ilan); if (ila) - ila_update_ipv6_locator(skb, &ila->xp.ip); + ila_update_ipv6_locator(skb, &ila->xp.ip, set_csum_neutral); rcu_read_unlock(); -- 2.39.2