From ceaa1fef65a7c2e017b260b879b310dd24888083 Mon Sep 17 00:00:00 2001 From: Andrey Vagin Date: Mon, 11 Feb 2013 05:50:17 +0000 Subject: tcp: adding a per-socket timestamp offset This functionality is used for restoring tcp sockets. A tcp timestamp depends on how long a system has been running, so it's differ for each host. The solution is to set a per-socket offset. A per-socket offset for a TIME_WAIT socket is inherited from a proper tcp socket. tcp_request_sock doesn't have a timestamp offset, because the repair mode for them are not implemented. Cc: "David S. Miller" Cc: Alexey Kuznetsov Cc: James Morris Cc: Hideaki YOSHIFUJI Cc: Patrick McHardy Cc: Eric Dumazet Cc: Pavel Emelyanov Signed-off-by: Andrey Vagin Signed-off-by: David S. Miller --- include/linux/tcp.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 6d0d46138ae8..f28408c07dc2 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -162,6 +162,8 @@ struct tcp_sock { u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ + u32 tsoffset; /* timestamp offset */ + struct list_head tsq_node; /* anchor in tsq_tasklet.head list */ unsigned long tsq_flags; @@ -353,6 +355,7 @@ struct tcp_timewait_sock { u32 tw_rcv_nxt; u32 tw_snd_nxt; u32 tw_rcv_wnd; + u32 tw_ts_offset; u32 tw_ts_recent; long tw_ts_recent_stamp; #ifdef CONFIG_TCP_MD5SIG -- cgit v1.3-14-g43fede From 93be6ce0e91b6a94783e012b1857a347a5e6e9f2 Mon Sep 17 00:00:00 2001 From: Andrey Vagin Date: Mon, 11 Feb 2013 05:50:18 +0000 Subject: tcp: set and get per-socket timestamp A timestamp can be set, only if a socket is in the repair mode. This patch adds a new socket option TCP_TIMESTAMP, which allows to get and set current tcp times stamp. Cc: "David S. Miller" Cc: Alexey Kuznetsov Cc: James Morris Cc: Hideaki YOSHIFUJI Cc: Patrick McHardy Cc: Eric Dumazet Cc: Pavel Emelyanov Signed-off-by: Andrey Vagin Signed-off-by: David S. Miller --- include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 9 +++++++++ 2 files changed, 10 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index e962faa5ab0d..6b1ead0b0c9d 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -111,6 +111,7 @@ enum { #define TCP_QUEUE_SEQ 21 #define TCP_REPAIR_OPTIONS 22 #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ +#define TCP_TIMESTAMP 24 struct tcp_repair_opt { __u32 opt_code; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 8a90bda96038..801b07b796f0 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2714,6 +2714,12 @@ static int do_tcp_setsockopt(struct sock *sk, int level, else err = -EINVAL; break; + case TCP_TIMESTAMP: + if (!tp->repair) + err = -EPERM; + else + tp->tsoffset = val - tcp_time_stamp; + break; default: err = -ENOPROTOOPT; break; @@ -2962,6 +2968,9 @@ static int do_tcp_getsockopt(struct sock *sk, int level, case TCP_USER_TIMEOUT: val = jiffies_to_msecs(icsk->icsk_user_timeout); break; + case TCP_TIMESTAMP: + val = tcp_time_stamp + tp->tsoffset; + break; default: return -ENOPROTOOPT; } -- cgit v1.3-14-g43fede