On Thu, Sep 13, 2018 at 04:41:16PM -0300, Marcelo Ricardo Leitner wrote: > On Thu, Sep 13, 2018 at 02:16:06PM +0200, Johannes Berg wrote: > > On Thu, 2018-09-13 at 14:12 +0200, Michal Kubecek wrote: > > > On Thu, Sep 13, 2018 at 02:02:53PM +0200, Johannes Berg wrote: > > > > On Thu, 2018-09-13 at 13:58 +0200, Michal Kubecek wrote: > > > > > > > > > The code looks correct to me but I have some doubts. Having a special > > > > > policy for MAC addresses may lead to adding one for IPv4 address (maybe > > > > > not, we can use NLA_U32 for them), IPv6 addresses and other data types > > > > > with fixed length. Wouldn't it be more helpful to add a variant of > > > > > NLA_BINARY (NLA_BINARY_EXACT?) which would fail/warn if attribute length > > > > > isn't equal to .len? > > > > > > > > Yeah, I guess we could do that, and then > > > > > > > > #define NLA_ETH_ADDR .len = ETH_ALEN, .type = NLA_BINARY_EXACT > > > > #define NLA_IP6_ADDR .len = 16, .type = NLA_BINARY_EXACT > > > > > > > > or so? > > > > > > Maybe rather > > > > > > #define NLA_ETH_ADDR NLA_BINARY_EXACT, .len = ETH_ALEN > > > #define NLA_IP6_ADDR NLA_BINARY_EXACT, .len = sizeof(struct in6_addr) > > > > > > so that one could write > > > > > > { .type = NLA_ETH_ADDR } > > > > Yeah, that's possible. I considered it for a second, but it was slightly > > too magical for my taste :-) > > > > Better pick a different "namespace", perhaps NLA_POLICY_ETH_ADDR or so? > > What about > #define NLA_FIELD_ETH_ADDR { .type = NLA_BINARY_EXACT, .len = ETH_ALEN } > > Or even > #define NLA_FIELD_BINARY_EXACT(_len) { .type = NLA_BINARY_EXACT, .len = (_len) } > #define NLA_FIELD_ETH_ADDR NLA_FIELD_BINARY_EXACT(ETH_ALEN) > > So that one would just: > [MYADDR] = NLA_FIELD_ETH_ADDR, Yes, that's how I understoold Johannes' proposal above. Michal Kubecek