diff options
Diffstat (limited to 'include/net/ipv6.h')
| -rw-r--r-- | include/net/ipv6.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 2aa86e1135a1..4308f2ada8b3 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -699,6 +699,26 @@ static inline void ip6_set_txhash(struct sock *sk) sk->sk_txhash = flow_hash_from_keys(&keys); } +static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, + __be32 flowlabel, bool autolabel) +{ + if (!flowlabel && (autolabel || net->ipv6.sysctl.auto_flowlabels)) { + __be32 hash; + + hash = skb_get_hash(skb); + + /* Since this is being sent on the wire obfuscate hash a bit + * to minimize possbility that any useful information to an + * attacker is leaked. Only lower 20 bits are relevant. + */ + hash ^= hash >> 12; + + flowlabel = hash & IPV6_FLOWLABEL_MASK; + } + + return flowlabel; +} + /* * Header manipulation */ |