diff options
| author | Tom Herbert | 2015-07-31 16:52:12 -0700 |
|---|---|---|
| committer | David S. Miller | 2015-07-31 17:07:11 -0700 |
| commit | 42240901f7c438636715b9cb6ed93f4441ffc091 (patch) | |
| tree | 44dfaaed66aa97ef93dc5921bedfac3808058210 /include | |
| parent | 67800f9b1f4eb5bbefc32e3f5044097354bc85b3 (diff) | |
ipv6: Implement different admin modes for automatic flow labels
Change the meaning of net.ipv6.auto_flowlabels to provide a mode for
automatic flow labels generation. There are four modes:
0: flow labels are disabled
1: flow labels are enabled, sockets can opt-out
2: flow labels are allowed, sockets can opt-in
3: flow labels are enabled and enforced, no opt-out for sockets
np->autoflowlabel is initialized according to the sysctl value.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/ipv6.h | 59 |
1 files changed, 46 insertions, 13 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 3e334b33ef3a..c02c1c03363a 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -707,36 +707,69 @@ static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow, } #if IS_ENABLED(CONFIG_IPV6) + +/* Sysctl settings for net ipv6.auto_flowlabels */ +#define IP6_AUTO_FLOW_LABEL_OFF 0 +#define IP6_AUTO_FLOW_LABEL_OPTOUT 1 +#define IP6_AUTO_FLOW_LABEL_OPTIN 2 +#define IP6_AUTO_FLOW_LABEL_FORCED 3 + +#define IP6_AUTO_FLOW_LABEL_MAX IP6_AUTO_FLOW_LABEL_FORCED + +#define IP6_DEFAULT_AUTO_FLOW_LABELS IP6_AUTO_FLOW_LABEL_OFF + static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, __be32 flowlabel, bool autolabel, struct flowi6 *fl6) { - if (!flowlabel && (autolabel || net->ipv6.sysctl.auto_flowlabels)) { - u32 hash; + u32 hash; - hash = skb_get_hash_flowi6(skb, fl6); + if (flowlabel || + net->ipv6.sysctl.auto_flowlabels == IP6_AUTO_FLOW_LABEL_OFF || + (!autolabel && + net->ipv6.sysctl.auto_flowlabels != IP6_AUTO_FLOW_LABEL_FORCED)) + return flowlabel; - /* 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; + hash = skb_get_hash_flowi6(skb, fl6); - flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK; + /* 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. + */ + rol32(hash, 16); - if (net->ipv6.sysctl.flowlabel_state_ranges) - flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG; - } + flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK; + + if (net->ipv6.sysctl.flowlabel_state_ranges) + flowlabel |= IPV6_FLOWLABEL_STATELESS_FLAG; return flowlabel; } + +static inline int ip6_default_np_autolabel(struct net *net) +{ + switch (net->ipv6.sysctl.auto_flowlabels) { + case IP6_AUTO_FLOW_LABEL_OFF: + case IP6_AUTO_FLOW_LABEL_OPTIN: + default: + return 0; + case IP6_AUTO_FLOW_LABEL_OPTOUT: + case IP6_AUTO_FLOW_LABEL_FORCED: + return 1; + } +} #else static inline void ip6_set_txhash(struct sock *sk) { } static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb, - __be32 flowlabel, bool autolabel) + __be32 flowlabel, bool autolabel, + struct flowi6 *fl6) { return flowlabel; } +static inline int ip6_default_np_autolabel(struct net *net) +{ + return 0; +} #endif |