An entry in data-types.txt offers space for a name-value table. Even if
one would refer to ARPHRD_*, some names are not derived from the
respective macro name and thus not intuitive.
Signed-off-by: Phil Sutter <phil@nwl.cc>
filter input iifname "(eth0)"
----------------------------
+INTERFACE TYPE TYPE
+~~~~~~~~~~~~~~~~~~~
+[options="header"]
+|==================
+|Name | Keyword | Size | Base type
+|Interface type |
+iface_type|
+16 bit |
+integer
+|===================
+
+The interface type type is used with *meta iiftype/oiftype* expression. Its values correspond with respective ARPHRD_* defines in <linux/if_arp.h>.
+
+.The following keywords will automatically resolve into an interface type type with given value
+
+[options="header"]
+|==================
+|Keyword | Value
+| ether | 1
+| ppp | 512
+| ipip | 768
+| ipip6 | 769
+| loopback | 772
+| sit | 776
+| ipgre | 778
+|===================
+
LINK LAYER ADDRESS TYPE
~~~~~~~~~~~~~~~~~~~~~~~
[options="header"]
Interface index (32 bit number). Can be specified numerically or as name of an existing interface.
|ifname|
Interface name (16 byte string). Does not have to exist.
-|iface_type|
-Interface type (16 bit number).
|uid|
User ID (32 bit number). Can be specified numerically or as user name.
|gid|