Commit 81e5d41d authored by Jesse Gross's avatar Jesse Gross
Browse files

openvswitch: Fix checksum update for actions on UDP packets. 



When modifying IP addresses or ports on a UDP packet we don't
correctly follow the rules for unchecksummed packets.  This meant
that packets without a checksum can be given a incorrect new checksum
and packets with a checksum can become marked as being unchecksummed.
This fixes it to handle those requirements.

Signed-off-by: default avatarJesse Gross <jesse@nicira.com>
parent 651a68ea

net/openvswitch/actions.c

+32 −12
Original line number Diff line number Diff line 
/*

 * Copyright (c) 2007-2011 Nicira Networks.

 * Copyright (c) 2007-2012 Nicira Networks.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of version 2 of the GNU General Public
@@ -145,9 +145,16 @@ static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, 
			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,

						 *addr, new_addr, 1);

	} else if (nh->protocol == IPPROTO_UDP) {

		if (likely(transport_len >= sizeof(struct udphdr)))

			inet_proto_csum_replace4(&udp_hdr(skb)->check, skb,

		if (likely(transport_len >= sizeof(struct udphdr))) {

			struct udphdr *uh = udp_hdr(skb);



			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {

				inet_proto_csum_replace4(&uh->check, skb,

							 *addr, new_addr, 1);

				if (!uh->check)

					uh->check = CSUM_MANGLED_0;

			}

		}

	}



	csum_replace4(&nh->check, *addr, new_addr);
@@ -197,8 +204,22 @@ static void set_tp_port(struct sk_buff *skb, __be16 *port, 
	skb->rxhash = 0;

}



static int set_udp_port(struct sk_buff *skb,

			const struct ovs_key_udp *udp_port_key)

static void set_udp_port(struct sk_buff *skb, __be16 *port, __be16 new_port)

{

	struct udphdr *uh = udp_hdr(skb);



	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {

		set_tp_port(skb, port, new_port, &uh->check);



		if (!uh->check)

			uh->check = CSUM_MANGLED_0;

	} else {

		*port = new_port;

		skb->rxhash = 0;

	}

}



static int set_udp(struct sk_buff *skb, const struct ovs_key_udp *udp_port_key)

{

	struct udphdr *uh;

	int err;
@@ -210,16 +231,15 @@ static int set_udp_port(struct sk_buff *skb, 


	uh = udp_hdr(skb);

	if (udp_port_key->udp_src != uh->source)

		set_tp_port(skb, &uh->source, udp_port_key->udp_src, &uh->check);

		set_udp_port(skb, &uh->source, udp_port_key->udp_src);



	if (udp_port_key->udp_dst != uh->dest)

		set_tp_port(skb, &uh->dest, udp_port_key->udp_dst, &uh->check);

		set_udp_port(skb, &uh->dest, udp_port_key->udp_dst);



	return 0;

}



static int set_tcp_port(struct sk_buff *skb,

			const struct ovs_key_tcp *tcp_port_key)

static int set_tcp(struct sk_buff *skb, const struct ovs_key_tcp *tcp_port_key)

{

	struct tcphdr *th;

	int err;
@@ -328,11 +348,11 @@ static int execute_set_action(struct sk_buff *skb, 
		break;



	case OVS_KEY_ATTR_TCP:

		err = set_tcp_port(skb, nla_data(nested_attr));

		err = set_tcp(skb, nla_data(nested_attr));

		break;



	case OVS_KEY_ATTR_UDP:

		err = set_udp_port(skb, nla_data(nested_attr));

		err = set_udp(skb, nla_data(nested_attr));

		break;

	}

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