From 4c507d2897bd9be810b3403ade73b04cf6fdfd4a Mon Sep 17 00:00:00 2001 From: Jiri Benc Date: Thu, 9 Feb 2012 09:35:49 +0000 Subject: [PATCH] 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: Jiri Benc Signed-off-by: David S. Miller --- include/linux/ipv6.h | 2 +- include/net/inet_sock.h | 1 + net/ipv4/af_inet.c | 1 + net/ipv4/ip_sockglue.c | 4 ++++ net/ipv4/tcp_ipv4.c | 1 + net/ipv6/af_inet6.c | 1 + net/ipv6/ipv6_sockglue.c | 4 ++++ net/ipv6/tcp_ipv6.c | 4 ++++ 8 files changed, 17 insertions(+), 1 deletion(-) diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index 4847a64d3c0a..8260ef779762 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -366,7 +366,7 @@ struct ipv6_pinfo { dontfrag:1; __u8 min_hopcount; __u8 tclass; - __u8 padding; + __u8 rcv_tclass; __u32 dst_cookie; diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 022f772c0ebe..ae17e1352d7e 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -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; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index f7b5670744f0..e588a34e85c2 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -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); diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 9125529dab95..ca50d9f9f8c1 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -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); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 4d6f81c818dc..94abee8cf563 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -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; diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 273f48d1df2e..5605f9dca87e 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -214,6 +214,7 @@ lookup_protocol: inet->mc_ttl = 1; inet->mc_index = 0; inet->mc_list = NULL; + inet->rcv_tos = 0; if (ipv4_config.no_pmtu_disc) inet->pmtudisc = IP_PMTUDISC_DONT; diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 6d6b65fdaa1a..63dd1f89ed7d 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -1017,6 +1017,10 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname, int hlim = np->mcast_hops; put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); } + if (np->rxopt.bits.rxtclass) { + int tclass = np->rcv_tclass; + put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); + } if (np->rxopt.bits.rxoinfo) { struct in6_pktinfo src_info; src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif : diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index d16414cb3421..12c6ece67f39 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1282,6 +1282,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newnp->opt = NULL; newnp->mcast_oif = inet6_iif(skb); newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; + newnp->rcv_tclass = ipv6_tclass(ipv6_hdr(skb)); /* * No need to charge this sock to the relevant IPv6 refcnt debug socks count @@ -1360,6 +1361,7 @@ static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, newnp->opt = NULL; newnp->mcast_oif = inet6_iif(skb); newnp->mcast_hops = ipv6_hdr(skb)->hop_limit; + newnp->rcv_tclass = ipv6_tclass(ipv6_hdr(skb)); /* Clone native IPv6 options from listening socket (if any) @@ -1562,6 +1564,8 @@ ipv6_pktoptions: np->mcast_oif = inet6_iif(opt_skb); if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit; + if (np->rxopt.bits.rxtclass) + np->rcv_tclass = ipv6_tclass(ipv6_hdr(skb)); if (ipv6_opt_accepted(sk, opt_skb)) { skb_set_owner_r(opt_skb, sk); opt_skb = xchg(&np->pktoptions, opt_skb); -- 2.39.2