From 518d8a2e9bad83c6040eccebc3d1f7388fc034e7 Mon Sep 17 00:00:00 2001 From: Or Gerlitz Date: Thu, 1 Jun 2017 21:37:37 +0300 Subject: [PATCH] net/flow_dissector: add support for dissection of misc ip header fields Add support for dissection of ip tos and ttl and ipv6 traffic-class and hoplimit. Both are dissected into the same struct. Uses similar call to ip dissection function as with tcp, arp and others. Signed-off-by: Or Gerlitz Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/flow_dissector.h | 11 +++++++++++ net/core/flow_dissector.c | 40 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+) diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h index efe34eec..e2663e9 100644 --- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -165,6 +165,16 @@ struct flow_dissector_key_tcp { __be16 flags; }; +/** + * struct flow_dissector_key_ip: + * @tos: tos + * @ttl: ttl + */ +struct flow_dissector_key_ip { + __u8 tos; + __u8 ttl; +}; + enum flow_dissector_key_id { FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */ FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */ @@ -186,6 +196,7 @@ enum flow_dissector_key_id { FLOW_DISSECTOR_KEY_ENC_PORTS, /* struct flow_dissector_key_ports */ FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */ FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */ + FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */ FLOW_DISSECTOR_KEY_MAX, }; diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 5a45943..fc5fc45 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -367,6 +367,40 @@ __skb_flow_dissect_tcp(const struct sk_buff *skb, key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF)); } +static void +__skb_flow_dissect_ipv4(const struct sk_buff *skb, + struct flow_dissector *flow_dissector, + void *target_container, void *data, const struct iphdr *iph) +{ + struct flow_dissector_key_ip *key_ip; + + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP)) + return; + + key_ip = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_IP, + target_container); + key_ip->tos = iph->tos; + key_ip->ttl = iph->ttl; +} + +static void +__skb_flow_dissect_ipv6(const struct sk_buff *skb, + struct flow_dissector *flow_dissector, + void *target_container, void *data, const struct ipv6hdr *iph) +{ + struct flow_dissector_key_ip *key_ip; + + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP)) + return; + + key_ip = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_IP, + target_container); + key_ip->tos = ipv6_get_dsfield(iph); + key_ip->ttl = iph->hop_limit; +} + /** * __skb_flow_dissect - extract the flow_keys struct and return it * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified @@ -469,6 +503,9 @@ ip: } } + __skb_flow_dissect_ipv4(skb, flow_dissector, + target_container, data, iph); + if (flags & FLOW_DISSECTOR_F_STOP_AT_L3) goto out_good; @@ -514,6 +551,9 @@ ipv6: goto out_good; } + __skb_flow_dissect_ipv6(skb, flow_dissector, + target_container, data, iph); + if (flags & FLOW_DISSECTOR_F_STOP_AT_L3) goto out_good; -- 2.7.4