Split $ipv6_prefer into $ip6addrctl_policy and $ipv6_activate_all_interfaces.

The $ip6addrctl_policy is a variable to choose a pre-defined address
selection policy set by ip6addrctl(8).
The keyword "ipv4_prefer" sets IPv4-preferred one described in Section 10.3,
the keyword "ipv6_prefer" sets IPv6-preferred one in Section 2.1 in RFC 3484,
respectively.  When "AUTO" is specified, it attempts to read
/etc/ip6addrctl.conf first.  If it is found, it reads and installs it as
a policy table.  If not, either of the two pre-defined policy tables is
chosen automatically according to $ipv6_activate_all_interfaces.

When $ipv6_activate_all_interfaces=NO, interfaces which have no corresponding
$ifconfig_IF_ipv6 is marked as IFDISABLED for security reason.

The default values are ip6addrctl_policy=AUTO and
ipv6_activate_all_interfaces=NO.

Discussed with:	ume and bz

1 files changed, 64 insertions, 24 deletions

diff --git a/share/man/man5/rc.conf.5 b/share/man/man5/rc.conf.5
index 7ad0cab..a884bff 100644
--- a/share/man/man5/rc.conf.5
+++ b/share/man/man5/rc.conf.5
@@ -1269,41 +1269,49 @@ If the variable is
 is added to all of
 .Va ifconfig_ Ns Ao Ar interface Ac Ns _ipv6
 and the
-.Va ipv6_prefer
+.Va ipv6_activate_all_interfaces
 is defined as
 .Dq Li YES .
 .Pp
 This variable is deprecated.  Use
-.Va ipv6_prefer
+.Va ifconfig_ Ns Ao Ar interface Ac Ns _ipv6
 and
-.Va ifconfig_ Ns Ao Ar interface Ac Ns _ipv6 .
+.Va ipv6_activate_all_interfaces
+if necessary.
 .It Va ipv6_prefer
 .Pq Vt bool
-This variable does the following:
-.Pp
 If the variable is
 .Dq Li YES ,
-the default policy of the source address selection set by
+the default address selection policy table set by
 .Xr ip6addrctl 8
 will be IPv6-preferred.
 .Pp
 If the variable is
 .Dq Li NO ,
-the default policy of the source address selection set by
+the default address selection policy table set by
 .Xr ip6addrctl 8
-will be IPv4-preferred, and all of interfaces which does not have the
-corrsponding
+will be IPv4-preferred.
+.Pp
+This variable is deprecated.  Use
+.Va ip6addtctl_policy
+instead.
+.It Va ipv6_activate_all_interfaces
+If the variable is
+.Dq Li NO ,
+all of interfaces which do not have the corrsponding
 .Va ifconfig_ Ns Ao Ar interface Ac Ns _ipv6
 variable will be marked as
-.Dq Li IFDISABLED .
-This means only IPv6 functionality on that interface is completely
-disabled.  For more details of
+.Dq Li IFDISABLED
+for security reason.  This means only IPv6 functionality on that interface
+is completely disabled.  For more details of
 .Dq Li IFDISABLED
 flag and keywords
 .Dq Li inet6 ifdisabled ,
 see
 .Xr ifconfig 8 .
 .Pp
+Default is
+.Dq Li NO .
 .It Va ipv6_privacy
 .Pq Vt bool
 If the variable is
@@ -1316,6 +1324,8 @@ This is the IPv6 equivalent of
 .Va network_interfaces .
 Normally manual configuration of this variable is not needed.
 .Pp
+.It Va ifconfig_ Ns Ao Ar interface Ac Ns _ipv6
+.Pq Vt str
 IPv6 functionality on an interface should be configured by
 .Va ifconfig_ Ns Ao Ar interface Ac Ns _ipv6 ,
 instead of setting ifconfig parameters in
@@ -1354,22 +1364,52 @@ this is the default output interface for scoped addresses.
 This works only with ipv6_gateway_enable="NO".
 .It Va ip6addrctl_enable
 .Pq Vt bool
-If set to
-.Dq Li YES ,
-install default address selection policy table
+This variable is to enable configuring default address selection policy table
 .Pq RFC 3484 .
-If a file
+The table can be specified in another variable
+.Va ip6addrctl_policy .
+For
+.Va ip6addrctl_policy
+the following keywords can be specified:
+.Dq Li ipv4_prefer ,
+.Dq Li ipv6_prefer ,
+or
+.Dq Li AUTO .
+.Pp
+If
+.Dq Li ipv4_prefer
+or
+.Dq Li ipv6_prefer
+is specified,
+.Xr ip6addrctl 8
+installs a pre-defined policy table described in Section 2.1
+.Pq IPv6-preferred
+or 10.3
+.Pq IPv4-preferred
+of RFC 3484.
+.Pp
+If
+.Dq Li AUTO
+is specified, it attempts to read a file
 .Pa /etc/ip6addrctl.conf
-is found the
+first.  If this file is found,
 .Xr ip6addrctl 8
-reads and installs it.
-If not, a pre-defined policy table will be installed.
-There are two pre-defined ones; IPv4-preferred and IPv6-preferred.
-If set
-.Va ipv6_prefer
-variable to
+reads and installs it.  If not found, a policy is automatically set
+according to
+.Va ipv6_activate_all_interfaces
+variable; if the variable is set to
 .Dq Li YES
-the IPv6-preferred one is used. Default is IPv4-preferred.
+the IPv6-preferred one is used.  Otherwise IPv4-preferred.
+.Pp
+The default value of
+.Va ip6addrctl_enable
+and
+.Va ip6addrctl_policy
+are
+.Dq Li YES
+and
+.Dq Li AUTO ,
+respectively.
 .It Va cloned_interfaces
 .Pq Vt str
 Set to the list of clonable network interfaces to create on this host.