From 7ea3a353848489fa817cc3076781d2c25a11d684 Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Fri, 16 Sep 2011 15:13:22 +0800
Subject: [PATCH] tcp: Allow per-tcpcb keepidle

- Add t_keepidle to tcpcb, it is initialized to tcp_keepidle
- The accepted socket's t_keepidle is inherited from the listen socket
- Add IPPROTO_TCP/TCP_KEEPIDLE socket option to get and set t_keepidle.
  The unit is milliseconds, which is as same as the unit of the sysctl
  node net.inet.tcp.keepidle
---
 sys/netinet/tcp.h          |  1 +
 sys/netinet/tcp_subr.c     |  1 +
 sys/netinet/tcp_syncache.c |  1 +
 sys/netinet/tcp_timer2.h   |  2 +-
 sys/netinet/tcp_usrreq.c   | 11 +++++++++++
 sys/netinet/tcp_var.h      |  2 ++
 6 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/sys/netinet/tcp.h b/sys/netinet/tcp.h
index a158a8ba61..08bd7450e8 100644
--- a/sys/netinet/tcp.h
+++ b/sys/netinet/tcp.h
@@ -163,5 +163,6 @@ struct tcphdr {
 #define TCP_KEEPINIT	0x20
 /* 0x40 unused */
 #define TCP_FASTKEEP	0x80
+#define TCP_KEEPIDLE	0x100
 
 #endif
diff --git a/sys/netinet/tcp_subr.c b/sys/netinet/tcp_subr.c
index 38335c8916..112536299c 100644
--- a/sys/netinet/tcp_subr.c
+++ b/sys/netinet/tcp_subr.c
@@ -695,6 +695,7 @@ tcp_newtcpcb(struct inpcb *inp)
 	bzero(tp->tt_msg, sizeof(*tp->tt_msg));
 
 	tp->t_keepinit = tcp_keepinit;
+	tp->t_keepidle = tcp_keepidle;
 
 	if (tcp_do_rfc1323)
 		tp->t_flags = (TF_REQ_SCALE | TF_REQ_TSTMP);
diff --git a/sys/netinet/tcp_syncache.c b/sys/netinet/tcp_syncache.c
index 25d38c1a6f..f6f44a65fc 100644
--- a/sys/netinet/tcp_syncache.c
+++ b/sys/netinet/tcp_syncache.c
@@ -864,6 +864,7 @@ syncache_socket(struct syncache *sc, struct socket *lso, struct mbuf *m)
 	 */
 	ltp = intotcpcb(linp);
 	tp->t_keepinit = ltp->t_keepinit;
+	tp->t_keepidle = ltp->t_keepidle;
 
 	tcp_create_timermsg(tp, port);
 	tcp_callout_reset(tp, tp->tt_keep, tp->t_keepinit, tcp_timer_keep);
diff --git a/sys/netinet/tcp_timer2.h b/sys/netinet/tcp_timer2.h
index 2ac650108b..29bbd534ef 100644
--- a/sys/netinet/tcp_timer2.h
+++ b/sys/netinet/tcp_timer2.h
@@ -74,7 +74,7 @@ tcp_getkeepidle(struct tcpcb *_tp)
 	if (_tp->t_flags & TF_FASTKEEP)
 		return (tcp_keepintvl);
 	else
-		return (tcp_keepidle);
+		return (_tp->t_keepidle);
 }
 
 static __inline void
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
index 0f0e5c273b..5f930f44c0 100644
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -1429,6 +1429,14 @@ tcp_ctloutput(netmsg_t msg)
 				error = EINVAL;
 			break;
 
+		case TCP_KEEPIDLE:
+			opthz = ((int64_t)optval * hz) / 1000;
+			if (opthz >= 1)
+				tp->t_keepidle = opthz;
+			else
+				error = EINVAL;
+			break;
+
 		default:
 			error = ENOPROTOOPT;
 			break;
@@ -1457,6 +1465,9 @@ tcp_ctloutput(netmsg_t msg)
 		case TCP_KEEPINIT:
 			optval = ((int64_t)tp->t_keepinit * 1000) / hz;
 			break;
+		case TCP_KEEPIDLE:
+			optval = ((int64_t)tp->t_keepidle * 1000) / hz;
+			break;
 		default:
 			error = ENOPROTOOPT;
 			break;
diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h
index e2031a5b57..e271d29ced 100644
--- a/sys/netinet/tcp_var.h
+++ b/sys/netinet/tcp_var.h
@@ -271,6 +271,8 @@ struct tcpcb {
 	int	rfbuf_cnt;		/* recv buffer autoscaling byte count */
 
 	int	t_keepinit;
+
+	int	t_keepidle;
 };
 
 #define	IN_FASTRECOVERY(tp)	(tp->t_flags & TF_FASTRECOVERY)
-- 
2.41.0