From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nikolay Aleksandrov Subject: [PATCH net-next v5 1/3] flow_dissector: factor out the ports extraction in skb_flow_get_ports Date: Wed, 2 Oct 2013 13:39:24 +0200 Message-ID: <1380713966-3891-2-git-send-email-nikolay@redhat.com> References: <1380713966-3891-1-git-send-email-nikolay@redhat.com> Cc: davem@davemloft.net, andy@greyhouse.net, fubar@us.ibm.com, eric.dumazet@gmail.com, vfalico@redhat.com To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:41255 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753458Ab3JBLnC (ORCPT ); Wed, 2 Oct 2013 07:43:02 -0400 In-Reply-To: <1380713966-3891-1-git-send-email-nikolay@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: Factor out the code that extracts the ports from skb_flow_dissect and add a new function skb_flow_get_ports which can be re-used. Suggested-by: Veaceslav Falico Signed-off-by: Nikolay Aleksandrov --- v2: new patch v3: fix a bug in skb_flow_dissect where thoff didn't have poff added by modifying thoff directly in skb_flow_get_ports as it's done anyway. Also add the necessary export symbol for skb_flow_get_ports. v4: integrate the thoff fix in skb_flow_get_ports v5: disintegrate the thoff fix, and re-base on Eric's fix This seems like a good idea because there're other users that can re-use it later as well. include/net/flow_keys.h | 1 + net/core/flow_dissector.c | 39 ++++++++++++++++++++++++++++----------- 2 files changed, 29 insertions(+), 11 deletions(-) diff --git a/include/net/flow_keys.h b/include/net/flow_keys.h index ac2439d..7e64bd8 100644 --- a/include/net/flow_keys.h +++ b/include/net/flow_keys.h @@ -14,4 +14,5 @@ struct flow_keys { }; bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow); +__be32 skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto); #endif diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 8d7d0dd..f8e25ac 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -25,9 +25,35 @@ static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *i memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst)); } +/** + * skb_flow_get_ports - extract the upper layer ports and return them + * @skb: buffer to extract the ports from + * @thoff: transport header offset + * @ip_proto: protocol for which to get port offset + * + * The function will try to retrieve the ports at offset thoff + poff where poff + * is the protocol port offset returned from proto_ports_offset + */ +__be32 skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto) +{ + int poff = proto_ports_offset(ip_proto); + + if (poff >= 0) { + __be32 *ports, _ports; + + ports = skb_header_pointer(skb, thoff + poff, + sizeof(_ports), &_ports); + if (ports) + return *ports; + } + + return 0; +} +EXPORT_SYMBOL(skb_flow_get_ports); + bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow) { - int poff, nhoff = skb_network_offset(skb); + int nhoff = skb_network_offset(skb); u8 ip_proto; __be16 proto = skb->protocol; @@ -150,16 +176,7 @@ ipv6: } flow->ip_proto = ip_proto; - poff = proto_ports_offset(ip_proto); - if (poff >= 0) { - __be32 *ports, _ports; - - ports = skb_header_pointer(skb, nhoff + poff, - sizeof(_ports), &_ports); - if (ports) - flow->ports = *ports; - } - + flow->ports = skb_flow_get_ports(skb, nhoff, ip_proto); flow->thoff = (u16) nhoff; return true; -- 1.8.1.4