Fortinet Network Device IPS User Manual

Page 29

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FortiGate IPS User Guide Version 3.0 MR7
01-30007-0080-20080916

29

Table 5: IP header keywords

Keyword and Value

Description

--dst_addr [!]<ipv4>;

The destination IP address.
To have the FortiGate search for a packet that does

not contain the specified address, add an

exclamation mark (!) before the IP address.
You can define up to 28 IP addresses or CIDR

blocks. Enclose the comma separated list in square

brackets.
Example:

dst_addr [172.20.0.0/16,10.1.0.0/16,
192.168.0.0/16]

--ip_id <field_int>;

Check the IP ID field for the specified value.

--ip_option {rr | eol | nop
| ts | sec | lsrr | ssrr |
satid | any};

Use the ip_option keyword to check various IP

option settings. The available options include:

rr: Check if IP RR (record route) option is
present.

eol: Check if IP EOL (end of list) option is
present.

nop: Check if IP NOP (no op) option is present.

ts: Check if IP TS (time stamp) option is
present.

sec: Check if IP SEC (IP security) option is
present.

lsrr: Check if IP LSRR (loose source routing)
option is present.

ssrr: Check if IP SSRR (strict source routing)
option is present.

satid: Check if IP SATID (stream identifier)
option is present.

any: Check if IP any option is present.

--ip_tos <field_int>;

Check the IP TOS field for the specified value.

--ip_ttl [< | >] <ttl_int>; Check the IP time-to-live value against the

specified value. Optionally, you can check for an IP

time-to-live greater-than (>) or less-than (<) the

specified value with the appropriate symbol.

--protocol
{<protocol_int> | tcp |
udp | icmp};

Check the IP protocol header.
Example:

--protocol tcp;

--src_addr [!]<ipv4>;

The source IP address.
To have the FortiGate search for a packet that does

not contain the specified address, add an

exclamation mark (!) before the IP address.
You can define up to 28 IP addresses or CIDR

blocks. Enclose the comma separated list in square

brackets.
Example:

src_addr 192.168.13.0/24

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