Configuring security checks
You can enable various security checks for incoming TCP/UDP packets. The packet is dropped if it matches one of the security rules that have been enabled. Use the appropriate syntax for your FortiSwitch model:
- Syntax (for FS-108D-POE, FS-112D-POE, and FS-224D-POE)
- Syntax (for FS-1xxE and FS-1xxF)
- Syntax (for all other FortiSwitch models)
Syntax (for FS-108D-POE, FS-112D-POE, and FS-224D-POE)
config switch security-feature
set tcp-syn-data {enable | disable}
set tcp-udp-port-zero {enable | disable}
set tcp_flag_zero {enable | disable}
set tcp_flag_FUP {enable | disable}
set tcp_flag_SF {enable | disable}
set tcp_flag_SR {enable | disable}
set tcp_frag_ipv4_icmp {enable | disable}
set tcp_arp_mac_mismatch {enable | disable}
set allow-mcast-sa {enable | disable}
end
Variable |
Description |
Default |
tcp-syn-data |
TCP SYN packet contains additional data (possible DoS attack). |
disable |
tcp-udp-port-zero |
TCP or UDP packet has the source or destination port set to zero. |
disable |
tcp_flag_zero |
TCP packet with all flags set to zero. |
disable |
tcp_flag_FUP |
TCP packet with FIN, URG and PSH flags set. |
disable |
tcp_flag_SF |
TCP packet with SYN and FIN flags set. |
disable |
tcp_flag_SR |
TCP packet with SYN and RST flags set. |
disable |
tcp_frag_ipv4_icmp |
Fragmented ICMPv4 packet. |
disable |
tcp_arp_mac_mismatch |
ARP packet with MAC source address mismatch between the layer- 2 header and the ARP packet payload. |
disable |
allow-mcast-sa |
Ethernet packet whose source MAC address is multicast. |
disable |
Syntax (for FS-1xxE and FS-1xxF)
config switch security-feature
set tcp-flag-zero {enable | disable}
set tcp-flag-FUP {enable | disable}
set tcp-flag-SF {enable | disable}
set tcp-flag-SR {enable | disable}
set arp-mac-mismatch {enable | disable}
set macsa-eq-macda {enable | disable}
set sip-eq-dip {enable | disable}
set tcp-port-eq {enable | disable}
set udp-port-eq {enable | disable}
set ip-pod {enable | disable}
set icmp-frag {enable | disable}
set tcp-frag-off-min {enable | disable}
set tcp-syn-sp-less-1024 {enable | disable}
set invalid-ipv4-hdr-len {enable | disable}
set gratuitous-arp {enable | disable}
end
Variable |
Description |
Default |
tcp-flag-zero | TCP packet with all flags set to zero. | disable |
tcp-flag-FUP |
TCP packet with FIN, URG, and PSH flags set. |
disable |
tcp-flag-SF |
TCP packet with SYN and FIN flags set. |
disable |
tcp-flag-SR | TCP packet with SYN and RST flags set. | disable |
arp-mac-mismatch | ARP packet with MAC source address mismatch between the MAC header and the ARP packet payload. | disable |
macsa-eq-macda | Packet with source MAC address equal to the destination MAC address. | disable |
sip-eq-dip | TCP packet with source IP address equal to the destination IP address. | disable |
tcp-port-eq | TCP packet with the same source and destination TCP port. | disable |
udp-port-eq |
IP packet with the same source and destination UDP port. |
disable |
ip-pod |
The IPv4/IPv6 packet length is larger than 64 kB. |
disable |
icmp-frag |
Fragmented ICMP packet. |
disable |
tcp-frag-off-min |
TCP non-initial fragments carry the TCP header. |
disable |
tcp-syn-sp-less-1024 |
TCP SYN packet with a source port less than 1024. |
disable |
invalid-ipv4-hdr-len |
IPv4 packet with a header length greater than the total length. NOTE: This command is available only on the FS-124F, FS-124F-FPOE, FS-124F-POE, FS-148F, FS-148F-FPOE, and FS-148F-POE models. |
disable |
gratuitous-arp |
Gratuitous ARP packet. NOTE: This command available only on the FS-108E, FS-108E-FPOE, FS-108E-POE, FS-108F, FS-108F-FPOE, FS-108F-POE, FS-124E, FS-124E-FPOE, FS-124E-POE, FS-148E, and FS-148E-POE models. |
disable |
Syntax (for all other FortiSwitch models)
config switch security-feature
set sip-eq-dip {enable | disable}
set tcp-flag {enable | disable}
set tcp-port-eq {enable | disable}
set tcp-flag-FUP {enable | disable}
set tcp-flag-SF {enable | disable}
set v4-first-frag {enable | disable}
set udp-port-eq {enable | disable}
set tcp-hdr-partial {enable | disable}
set macsa-eq-macda {enable | disable}
set allow-mcast-sa {enable | disable}
set allow-sa-mac-all-zero {enable | disable}
end
Variable |
Description |
Default |
sip-eq-dip |
TCP packet with the same source IP address and destination IP address. |
disable |
tcp-flag |
DoS attack checking for TCP flags. |
disable |
tcp-port-eq |
TCP packet with the same source and destination TCP port. |
disable |
tcp-flag-FUP |
TCP packet with FIN, URG, and PSH flags set, and sequence number is zero. |
disable |
tcp-flag-SF |
TCP packet with SYN and FIN flags set. |
disable |
v4-first-frag |
DoS attack checking for IPv4 first fragment. |
disable |
udp-port-eq |
IP packet with the same source and destination UDP port. |
disable |
tcp-hdr-partial |
TCP packet with partial header. |
disable |
macsa-eq-macda |
Packet with the same source MAC address and destination MAC address. |
disable |
allow-mcast-sa |
Ethernet packet whose source MAC address is multicast. |
disable |
allow-sa-mac-all-zero |
Ethernet packet whose source MAC address is all zeros. |
disable |