Troubleshooting guide

Appendix A: State Tables for VPN-1/FireWall-1 4.0 The basic structure of a connection in a table entry
Advanced Technical Reference Guide 4.1 • June 2000 142
Table Attributes
A table may have the following attributes:
Attribute Description
expcall <function> Call function when an entry is deleted or expires from this table. Can also appear as “free
function”.
expires <time> The amount of time the connection is allowed to stay in the table.
hashsize <size> In the connections table, the size of the connection table hash. This value should be the
power of 2 closest to the size of the table.
implies
<table_name>
When an entry goes out from this table it will go out from the specified table.
kbuf <x> The xth argument in the value section is a pointer to an internal data structure (mostly used
in encryption).
keep Keep the entries after a reinstallation of the policy.
limit <x> Maximum number of entries that are allowed in the table.
refresh Reset the expiry timer whenever an entry in the table is accessed.
sync Synchronize this table if using FireWall-1 Synchronization.
The basic structure of a connection in a table entry
Many tables store entries that represent connections. In those tables, the first five fields follow a common
standard. An example of these five fields is shown below along with the meaning of each field..
Other connections in other tables will, in most cases, contain the same five key fields but will store different
field values. These first five fields are known as the “key” part of the table entry.
<c7cb4764, 0000008a, c7cb47ff, 00000050, 00000006 … >
Field Example value Description
1 c7cb4764 Source IP address
2 0000008a Source port
3 c7cb47ff Destination IP address
4 00000050 Destination port
5 00000006 IP protocol number, as defined in RFC 1700 (11 – UDP, 6 – TCP 1 – ICMP…)
Note: FireWall-1 is able to search on the “key” entries of the table.