Re: [tcpdump-workers] Requesting DLT_* values for Ethernet switches proprietary tagging protocol

2019-01-18 Thread Florian Fainelli
On 1/18/19 6:13 AM, Michael Richardson wrote: > > Guy Harris wrote: > >> OK, then requesting 10 DLT values, one per-tag is reasonable? > > > Yes. > > This is totally how it should be done. > > Guy, do we want to allocate 16 or 32 values, aligned, so that the > it be can DLT_TAG_BASE +

Re: [tcpdump-workers] Requesting DLT_* values for Ethernet switches proprietary tagging protocol

2019-01-18 Thread Florian Fainelli
On 1/17/19 9:55 PM, Guy Harris wrote: > On Jan 17, 2019, at 9:16 PM, Florian Fainelli wrote: > >> On 1/17/2019 8:12 PM, Guy Harris wrote: >> >>> But if /sys/class/net/{device}/dsa doesn't exist in pre-4.19 kernels, how >>> can you determine, from userland, whether a device is a DSA management-po

Re: [tcpdump-workers] Requesting DLT_* values for Ethernet switches proprietary tagging protocol

2019-01-18 Thread Guy Harris
On Jan 18, 2019, at 6:13 AM, Michael Richardson wrote: > Guy, do we want to allocate 16 or 32 values, aligned, so that the > it be can DLT_TAG_BASE + DSA_TAG_xx maps? "Aligned" would mean you want to support DLT_TAG_BASE | DSA_TAG_xx; alignment is necessary to support ORing in the tag type, but

Re: [tcpdump-workers] Requesting DLT_* values for Ethernet switches proprietary tagging protocol

2019-01-18 Thread Guy Harris
On Jan 18, 2019, at 10:24 AM, Florian Fainelli wrote: > In pre-4.19 kernels there was really no way you could reliably tell a > DSA management interface apart from a regular Ethernet device in the > system, even by scanning the network device's relationship through > ifindex etc. ... >