| Match on IPv4 header options like source routing, record route, |
| timestamp and router-alert. |
| .TP |
| .B "--ssrr" |
| To match packets with the flag strict source routing. |
| .TP |
| .B "--lsrr" |
| To match packets with the flag loose source routing. |
| .TP |
| .B "--no-srr" |
| To match packets with no flag for source routing. |
| .TP |
| .B "\fR[\fB!\fR]\fB --rr" |
| To match packets with the RR flag. |
| .TP |
| .B "\fR[\fB!\fR]\fB --ts" |
| To match packets with the TS flag. |
| .TP |
| .B "\fR[\fB!\fR]\fB --ra" |
| To match packets with the router-alert option. |
| .TP |
| .B "\fR[\fB!\fR]\fB --any-opt" |
| To match a packet with at least one IP option, or no IP option |
| at all if ! is chosen. |
| .TP |
| Examples: |
| .TP |
| $ iptables -A input -m ipv4options --rr -j DROP |
| will drop packets with the record-route flag. |
| .TP |
| $ iptables -A input -m ipv4options --ts -j DROP |
| will drop packets with the timestamp flag. |
