What is a valid TC (QoS) u32 filter handle id

Question

I'm trying to find a way of using some kind of naming convention to distribute unique id's among my app modules.
I want each up to have a range of id's it can use to create TC filters / classes etc..
As it this page states :

A u32 handle is actually 3 numbers, written like this: 800:0:3. They are all in hex.

Valid filter item handles range from 1 to ffe hex.

But when I try to set handle 1:1:1 it fails.

Here is the parsing of the u32 handle id from the iproute2-3.17.0 module : (it is not necessarily the version installed on the machine)

static int get_u32_handle(__u32 *handle, const char *str)
{
    __u32 htid=0, hash=0, nodeid=0;
    char *tmp = strchr(str, ':');

    if (tmp == NULL) {
        if (memcmp("0x", str, 2) == 0)
            return get_u32(handle, str, 16);
        return -1;
    }
    htid = strtoul(str, &tmp, 16);
    if (tmp == str && *str != ':' && *str != 0)
        return -1;
    if (htid>=0x1000)
        return -1;
    if (*tmp) {
        str = tmp+1;
        hash = strtoul(str, &tmp, 16);
        if (tmp == str && *str != ':' && *str != 0)
            return -1;
        if (hash>=0x100)
            return -1;
        if (*tmp) {
            str = tmp+1;
            nodeid = strtoul(str, &tmp, 16);
            if (tmp == str && *str != 0)
                return -1;
            if (nodeid>=0x1000)
                return -1;
        }
    }
    *handle = (htid<<20)|(hash<<12)|nodeid;
    return 0;
}

It looks like it should get any XXX:XXX:XXX as long as xxx < 0x1000, but it fails to do so. (I think the first part (which is the hash must be 800), any other value fails to be parsed.

Answer 1

I don't know the iproute2 library, but tc filter show dev eth0 shows them in '800::123' format. (LibNL's sample nl-cls-list shows same handle as '8000:123'.) Also, tc filter add accepts handle in the form of '0x123'.

Try setting the first field as 800, and second as 0 or empty. Does this help?