On 6/28/18 7:08 AM, Jiri Pirko wrote: > Create dummy device with clsact first: > # ip link add type dummy > # tc qdisc add dev dummy0 clsact > > There is no template assigned by default: > # tc chaintemplate show dev dummy0 ingress > > Add a template of type flower allowing to insert rules matching on last > 2 bytes of destination mac address: > # tc chaintemplate add dev dummy0 ingress proto ip flower dst_mac > 00:00:00:00:00:00/00:00:00:00:FF:FF > > The template is now showed in the list: > # tc chaintemplate show dev dummy0 ingress > chaintemplate flower chain 0 > dst_mac 00:00:00:00:00:00/00:00:00:00:ff:ff > eth_type ipv4 > > Add another template, this time for chain number 22: > # tc chaintemplate add dev dummy0 ingress proto ip chain 22 flower dst_ip > 0.0.0.0/16 > # tc chaintemplate show dev dummy0 ingress > chaintemplate flower chain 0 > dst_mac 00:00:00:00:00:00/00:00:00:00:ff:ff > eth_type ipv4 > chaintemplate flower chain 22 > eth_type ipv4 > dst_ip 0.0.0.0/16 > > Add a filter that fits the template: > # tc filter add dev dummy0 ingress proto ip flower dst_mac > aa:bb:cc:dd:ee:ff/00:00:00:00:00:0F action drop > > Addition of filters that does not fit the template would fail: > # tc filter add dev dummy0 ingress proto ip flower dst_mac > aa:11:22:33:44:55/00:00:00:FF:00:00 action drop > Error: Mask does not fit the template. > We have an error talking to the kernel, -1 > # tc filter add dev dummy0 ingress proto ip flower dst_ip 10.0.0.1 action drop > Error: Mask does not fit the template. > We have an error talking to the kernel, -1 > > Additions of filters to chain 22: > # tc filter add dev dummy0 ingress proto ip chain 22 flower dst_ip 10.0.0.1/8 > action drop > # tc filter add dev dummy0 ingress proto ip chain 22 flower dst_ip 10.0.0.1 > action drop > Error: Mask does not fit the template. > We have an error talking to the kernel, -1 > # tc filter add dev dummy0 ingress proto ip chain 22 flower dst_ip > 10.0.0.1/24 action drop > Error: Mask does not fit the template. > We have an error talking to the kernel, -1 > > Removal of a template from non-empty chain would fail: > # tc chaintemplate del dev dummy0 ingress > Error: The chain is not empty, unable to delete template. > We have an error talking to the kernel, -1
Why this restriction? It's a template, so why can't it be removed regardless of whether there are filters? > > Once the chain is flushed, the template could be removed: > # tc filter del dev dummy0 ingress > # tc chaintemplate del dev dummy0 ingress >