Commit 4c507d28 authored by Jiri Benc's avatar Jiri Benc Committed by David S. Miller
Browse files

net: implement IP_RECVTOS for IP_PKTOPTIONS 

Currently, it is not easily possible to get TOS/DSCP value of packets from
an incoming TCP stream. The mechanism is there, IP_PKTOPTIONS getsockopt
with IP_RECVTOS set, the same way as incoming TTL can be queried. This is
not actually implemented for TOS, though.

This patch adds this functionality, both for IPv4 (IP_PKTOPTIONS) and IPv6
(IPV6_2292PKTOPTIONS). For IPv4, like in the IP_RECVTTL case, the value of
the TOS field is stored from the other party's ACK.

This is needed for proxies which require DSCP transparency. One such example
is at http://zph.bratcheda.org/

.

Signed-off-by: default avatarJiri Benc <jbenc@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 7a3198a8

include/linux/ipv6.h

+1 −1
Original line number Diff line number Diff line
@@ -366,7 +366,7 @@ struct ipv6_pinfo { 
				dontfrag:1;

	__u8			min_hopcount;

	__u8			tclass;

	__u8			padding;

	__u8			rcv_tclass;



	__u32			dst_cookie;

include/net/inet_sock.h

+1 −0
Original line number Diff line number Diff line
@@ -168,6 +168,7 @@ struct inet_sock { 
				transparent:1,

				mc_all:1,

				nodefrag:1;

	__u8			rcv_tos;

	int			uc_index;

	int			mc_index;

	__be32			mc_addr;

net/ipv4/af_inet.c

+1 −0
Original line number Diff line number Diff line
@@ -381,6 +381,7 @@ lookup_protocol: 
	inet->mc_all	= 1;

	inet->mc_index	= 0;

	inet->mc_list	= NULL;

	inet->rcv_tos	= 0;



	sk_refcnt_debug_inc(sk);

net/ipv4/ip_sockglue.c

+4 −0
Original line number Diff line number Diff line
@@ -1289,6 +1289,10 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, 
			int hlim = inet->mc_ttl;

			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);

		}

		if (inet->cmsg_flags & IP_CMSG_TOS) {

			int tos = inet->rcv_tos;

			put_cmsg(&msg, SOL_IP, IP_TOS, sizeof(tos), &tos);

		}

		len -= msg.msg_controllen;

		return put_user(len, optlen);

	}

net/ipv4/tcp_ipv4.c

+1 −0
Original line number Diff line number Diff line
@@ -1463,6 +1463,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, 
	ireq->opt	      = NULL;

	newinet->mc_index     = inet_iif(skb);

	newinet->mc_ttl	      = ip_hdr(skb)->ttl;

	newinet->rcv_tos      = ip_hdr(skb)->tos;

	inet_csk(newsk)->icsk_ext_hdr_len = 0;

	if (inet_opt)

		inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;

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