bring in description for KAME IPv6 changes.

XXX it looks that sysctl.3 lacks most of PF_INET items.
Reviewed by:	shin
Obtained from:	KAME (netbsd-current)

lib/libc/gen/sysctl.3

@@ -453,7 +453,8 @@ privilege may change the value.
 .Bl -column "Second level nameXXXXXX" "routing messagesXXX" -offset indent
 .It Sy Pa Second level name	Type	Changeable
 .It PF\_ROUTE	routing messages	no
-.It PF\_INET	internet values	yes
+.It PF\_INET	IPv4 values	yes
+.It PF\_INET6	IPv6 values	yes
 .El
 .Pp
 .Bl -tag -width "123456"
@@ -475,7 +476,8 @@ The fifth and sixth level names are as follows:
 .It NET\_RT\_IFLIST	None
 .El
 .It Li PF_INET
-Get or set various global information about the internet protocols.
+Get or set various global information about the IPv4
+.Pq Internet Protocol version 4 .
 The third level name is the protocol.
 The fourth level name is the variable name.
 The currently defined protocols and names are:
@@ -511,6 +513,154 @@ This value applies to normal transport protocols, not to ICMP.
 .It Li udp.checksum
 Returns 1 when UDP checksums are being computed and checked.
 Disabling UDP checksums is strongly discouraged.
+.Pp
+For variables net.*.ipsec, please refer to
+.Xr ipsec 4 .
+.El
+.It Li PF_INET6
+Get or set various global information about the IPv6
+.Pq Internet Protocol version 6 .
+The third level name is the protocol.
+The fourth level name is the variable name.
+The currently defined protocols and names are:
+.Bl -column ProtocolXX nd6_useloopbackXX TypeXX ChangeableXX
+.It Pa Protocol	Variable	Type	Changeable
+.It ip6	forwarding	integer	yes
+.It ip6	redirect	integer	yes
+.It ip6	hlim	integer	yes
+.It ip6	maxfragpackets	integer	yes
+.It ip6	accept_rtadv	integer	yes
+.It ip6	keepfaith	integer	yes
+.It ip6	log_interval	integer	yes
+.It ip6	hdrnestlimit	integer	yes
+.It ip6	dad_count	integer	yes
+.It ip6	auto_flowlabel	integer	yes
+.It ip6	defmcasthlim	integer	yes
+.It ip6	gif_hlim	integer	yes
+.It ip6	kame_version	string	no
+.It ip6	use_deprecated	integer	yes
+.It ip6	rr_prune	integer	yes
+.It ip6	mapped_addr	integer	yes
+.It icmp6	rediraccept	integer	yes
+.It icmp6	redirtimeout	integer	yes
+.It icmp6	errratelimit	integer	yes
+.It icmp6	nd6_prune	integer	yes
+.It icmp6	nd6_delay	integer	yes
+.It icmp6	nd6_umaxtries	integer	yes
+.It icmp6	nd6_mmaxtries	integer	yes
+.It icmp6	nd6_useloopback	integer	yes
+.It icmp6	nd6_proxyall	integer	yes
+.El
+.Pp
+The variables are as follows:
+.Bl -tag -width "123456"
+.It Li ip6.forwarding
+Returns 1 when IPv6 forwarding is enabled for the node,
+meaning that the node is acting as a router.
+.It Li ip6.redirect
+Returns 1 when ICMPv6 redirects may be sent by the node.
+This option is ignored unless the node is routing IP packets,
+and should normally be enabled on all systems.
+.It Li ip6.hlim
+The default hop limit value for an IPv6 unicast packet sourced by the node.
+This value applies to all the transport protocols on top of IPv6.
+There are APIs to override the value.
+.\", as documented in
+.\".Xr ip6 4 .
+.It Li ip6.maxfragpackets
+The maximum number of fragmented packets the node will accept.
+0 means that the node will not accept any fragmented packets.
+-1 means that the node will accept as many fragmented packets as it receives.
+The flag is provided basically for avoiding possible DoS attacks.
+.It Li ip6.accept_rtadv
+If set to non-zero, the node will accept ICMPv6 router advertisement packets
+and autoconfigures address prefixes and default routers.
+The node must be a host
+.Pq not a router
+for the option to be meaningful.
+.It Li ip6.keepfaith
+If set to non-zero, it enables
+.Dq FAITH
+TCP relay IPv6-to-IPv4 translator code in the kernel.
+Refer
+.Xr faith 4
+and
+.Xr faithd 8
+for detail.
+.It Li ip6.log_interval
+The variable controls amount of logs generated by IPv6 packet
+forwarding engine, by seting interval between log output
+.Pq in seconds .
+.It Li ip6.hdrnestlimit
+The number of IPv6 extension headers permitted on incoming IPv6 packets.
+If set to 0, the node will accept as many extension headers as possible.
+.It Li ip6.dad_count
+The variable cofigures number of IPv6 DAD
+.Pq duplicated address detection
+probe packets.
+The packets will be generated when IPv6 interface addresses are configured.
+.It Li ip6.auto_flowlabel
+On connected transport protocol packets,
+fill IPv6 flowlabel field to help intermediate routers to identify packet flows.
+.It Li ip6.defmcasthlim
+The default hop limit value for an IPv6 multicast packet sourced by the node.
+This value applies to all the transport protocols on top of IPv6.
+There are APIs to override the value.
+.\", as documented in
+.\".Xr ip6 4 .
+.It Li ip6.gif_hlim
+The maximum hop limit value for an IPv6 packet generated by
+.Xr gif 4
+tunnel interface.
+.It Li ip6.kame_version
+The string identifies the version of KAME IPv6 stack implemented in the kernel.
+.It Li ip6.use_deprecated
+The variable controls use of deprecated address, specified in RFC2462 5.5.4.
+.It Li ip6.rr_prune
+The variable specifies interval between IPv6 router renumbering prefix
+babysitting, in seconds.
+.It Li ip6.mapped_addr
+The variable controls use of IPv4 mapped address on AF_INET6 sockets.
+.It Li icmp6.rediraccept
+If set to non-zero, the host will accept ICMPv6 redirect packets.
+Note that IPv6 routers will never accept ICMPv6 redirect packets,
+and the variable is meaningful on IPv6 hosts
+.Pq non-router
+only.
+.It Li icmp6.redirtimeout
+The variable specifies lifetime of routing entries generated by incoming
+ICMPv6 redirect.
+.It Li icmp6.errratelimit
+The variable specifies minimum interval between ICMPv6 error messages,
+in microseconds.
+.It Li icmp6.nd6_prune
+The variable specifies interval between IPv6 neighbor cache babysitting,
+in seconds.
+.It Li icmp6.nd6_delay
+The variable specifies
+.Dv DELAY_FIRST_PROBE_TIME
+timing constant in IPv6 neighbor discovery specification
+.Pq RFC2461 ,
+in seconds.
+.It Li icmp6.nd6_umaxtries
+The variable specifies
+.Dv MAX_UNICAST_SOLICIT
+constant in IPv6 neighbor discovery specification
+.Pq RFC2461 .
+.It Li icmp6.nd6_mmaxtries
+The variable specifies
+.Dv MAX_MULTICAST_SOLICIT
+constant in IPv6 neighbor discovery specification
+.Pq RFC2461 .
+.It Li icmp6.nd6_useloopback
+If set to non-zero, kernel IPv6 stack will use loopback interface for
+local traffic.
+.It Li icmp6.nd6_proxyall
+The variable enables proxy neighbor advertisements.
+.El
+.Pp
+For variables net.*.ipsec6, please refer to
+.Xr ipsec 4 .
 .El
 .Sh CTL_USER
 The string and integer information available for the CTL_USER level
@@ -729,10 +879,12 @@ definitions for third level profiling identifiers
 .It Pa <vm/vm_param.h>
 definitions for second level virtual memory identifiers
 .It Pa <netinet/in.h>
-definitions for third level Internet identifiers and
+definitions for third level IPv4/IPv6 identifiers and
-fourth level IP identifiers
+fourth level IPv4/v6 identifiers
 .It Pa <netinet/icmp_var.h>
 definitions for fourth level ICMP identifiers
+.It Pa <netinet/icmp6.h>
+definitions for fourth level ICMPv6 identifiers
 .It Pa <netinet/udp_var.h>
 definitions for fourth level UDP identifiers
 .El

share/man/man7/hier.7

@@ -187,6 +187,10 @@ see
 C include files for Internet standard protocols;
 see
 .Xr inet 4
+.It Li netinet6/
+C include files for Internet protocol version 6;
+see
+.Xr inet6 4
 .It Li netipx/
 IPX/SPX protocol stacks
 .It Li netkey/