On 6/28/18 8:29 AM, Jiri Pirko wrote: > Thu, Jun 28, 2018 at 04:18:47PM CEST, dsah...@gmail.com wrote: >> 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? > > That means you could start to insert filters that does not match the > original template. I wanted to avoid it. The chain is utilized in hw for > the original template, the filter insertion would have to be sanitized > in driver. With this restriction, drivers can depend on filters always > be fitting. >
Then the hardware driver should have that restriction not the core tc code.
