Nikolay Aleksandrov
2022-Mar-10 15:57 UTC
[Bridge] [PATCH net-next 1/3] net: bridge: add fdb flag to extent locked port feature
On 10/03/2022 17:38, Hans Schultz wrote:> On tor, mar 10, 2022 at 16:42, Nikolay Aleksandrov <razor at blackwall.org> wrote: >> On 10/03/2022 16:23, Hans Schultz wrote: >>> Add an intermediate state for clients behind a locked port to allow for >>> possible opening of the port for said clients. This feature corresponds >>> to the Mac-Auth and MAC Authentication Bypass (MAB) named features. The >>> latter defined by Cisco. >>> >>> Signed-off-by: Hans Schultz <schultz.hans+netdev at gmail.com> >>> --- >>> include/uapi/linux/neighbour.h | 1 + >>> net/bridge/br_fdb.c | 6 ++++++ >>> net/bridge/br_input.c | 11 ++++++++++- >>> net/bridge/br_private.h | 3 ++- >>> 4 files changed, 19 insertions(+), 2 deletions(-) >>> >>> diff --git a/include/uapi/linux/neighbour.h b/include/uapi/linux/neighbour.h >>> index db05fb55055e..83115a592d58 100644 >>> --- a/include/uapi/linux/neighbour.h >>> +++ b/include/uapi/linux/neighbour.h >>> @@ -208,6 +208,7 @@ enum { >>> NFEA_UNSPEC, >>> NFEA_ACTIVITY_NOTIFY, >>> NFEA_DONT_REFRESH, >>> + NFEA_LOCKED, >>> __NFEA_MAX >>> }; >> >> Hmm, can you use NDA_FLAGS_EXT instead ? >> That should simplify things and reduce the nl size. >> > > I am using NDA_FDB_EXT_ATTRS. NFEA_LOCKED is just the > flag as the other flags section is full wrt the normal flags, but maybe it > doesn't fit in that section? >Actually wait a second, this is completely wrong use of NDA_FDB_EXT_ATTRS. That is a nested attribute, so the code below is wrong. More below..> I will just note that iproute2 support for parsing nested attributes > does not work, thus the BR_FDB_NOTIFY section (lines 150-165) are > obsolete with respect to iproute2 as it is now. I cannot rule out that > someone has some other tool that can handle this BR_FDB_NOTIFY, but I > could not make iproute2 as it stands handle nested attributes. And of > course there is no handling of NDA_FDB_EXT_ATTRS in iproute2 now. > >>> #define NFEA_MAX (__NFEA_MAX - 1) >>> diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c >>> index 6ccda68bd473..396dcf3084cf 100644 >>> --- a/net/bridge/br_fdb.c >>> +++ b/net/bridge/br_fdb.c >>> @@ -105,6 +105,7 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, >>> struct nda_cacheinfo ci; >>> struct nlmsghdr *nlh; >>> struct ndmsg *ndm; >>> + u8 ext_flags = 0; >>> >>> nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags); >>> if (nlh == NULL) >>> @@ -125,11 +126,16 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, >>> ndm->ndm_flags |= NTF_EXT_LEARNED; >>> if (test_bit(BR_FDB_STICKY, &fdb->flags)) >>> ndm->ndm_flags |= NTF_STICKY; >>> + if (test_bit(BR_FDB_ENTRY_LOCKED, &fdb->flags)) >>> + ext_flags |= 1 << NFEA_LOCKED; >>> >>> if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr)) >>> goto nla_put_failure; >>> if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex)) >>> goto nla_put_failure; >>> + if (nla_put_u8(skb, NDA_FDB_EXT_ATTRS, ext_flags)) >>> + goto nla_put_failure; >>> +This is wrong. NDA_FDB_EXT_ATTRS is a nested attribute, you can't use it as a u8. You need to have this structure: [ NDA_FDB_EXT_ATTRS ] ` [ NFEA_LOCKED ] But that's why I asked if you could use the NDA_FLAGS_EXT attribute. You can see the logic from the neigh code. Also note that you need to account for the new attribute's size in fdb_nlmsg_size().>>> ci.ndm_used = jiffies_to_clock_t(now - fdb->used); >>> ci.ndm_confirmed = 0; >>> ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated); >>> diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c >>> index e0c13fcc50ed..897908484b18 100644 >>> --- a/net/bridge/br_input.c >>> +++ b/net/bridge/br_input.c >>> @@ -75,6 +75,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb >>> struct net_bridge_mcast *brmctx; >>> struct net_bridge_vlan *vlan; >>> struct net_bridge *br; >>> + unsigned long flags = 0; >> >> Please move this below... >> >>> u16 vid = 0; >>> u8 state; >>> >>> @@ -94,8 +95,16 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb >>> br_fdb_find_rcu(br, eth_hdr(skb)->h_source, vid); >>> >>> if (!fdb_src || READ_ONCE(fdb_src->dst) != p || >>> - test_bit(BR_FDB_LOCAL, &fdb_src->flags)) >>> + test_bit(BR_FDB_LOCAL, &fdb_src->flags)) { >>> + if (!fdb_src) { >> >> ... here where it's only used. >> > > Forgot that one. Shall do! > >>> + set_bit(BR_FDB_ENTRY_LOCKED, &flags); >>> + br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, flags); >>> + } >>> goto drop; >>> + } else { >>> + if (test_bit(BR_FDB_ENTRY_LOCKED, &fdb_src->flags)) >>> + goto drop; >>> + } >>> } >>> >>> nbp_switchdev_frame_mark(p, skb); >>> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h >>> index 48bc61ebc211..f5a0b68c4857 100644 >>> --- a/net/bridge/br_private.h >>> +++ b/net/bridge/br_private.h >>> @@ -248,7 +248,8 @@ enum { >>> BR_FDB_ADDED_BY_EXT_LEARN, >>> BR_FDB_OFFLOADED, >>> BR_FDB_NOTIFY, >>> - BR_FDB_NOTIFY_INACTIVE >>> + BR_FDB_NOTIFY_INACTIVE, >>> + BR_FDB_ENTRY_LOCKED, >>> }; >>> >>> struct net_bridge_fdb_key {
Hans Schultz
2022-Mar-10 16:11 UTC
[Bridge] [PATCH net-next 1/3] net: bridge: add fdb flag to extent locked port feature
On tor, mar 10, 2022 at 17:57, Nikolay Aleksandrov <razor at blackwall.org> wrote:> On 10/03/2022 17:38, Hans Schultz wrote: >> On tor, mar 10, 2022 at 16:42, Nikolay Aleksandrov <razor at blackwall.org> wrote: >>> On 10/03/2022 16:23, Hans Schultz wrote: >>>> Add an intermediate state for clients behind a locked port to allow for >>>> possible opening of the port for said clients. This feature corresponds >>>> to the Mac-Auth and MAC Authentication Bypass (MAB) named features. The >>>> latter defined by Cisco. >>>> >>>> Signed-off-by: Hans Schultz <schultz.hans+netdev at gmail.com> >>>> --- >>>> include/uapi/linux/neighbour.h | 1 + >>>> net/bridge/br_fdb.c | 6 ++++++ >>>> net/bridge/br_input.c | 11 ++++++++++- >>>> net/bridge/br_private.h | 3 ++- >>>> 4 files changed, 19 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/include/uapi/linux/neighbour.h b/include/uapi/linux/neighbour.h >>>> index db05fb55055e..83115a592d58 100644 >>>> --- a/include/uapi/linux/neighbour.h >>>> +++ b/include/uapi/linux/neighbour.h >>>> @@ -208,6 +208,7 @@ enum { >>>> NFEA_UNSPEC, >>>> NFEA_ACTIVITY_NOTIFY, >>>> NFEA_DONT_REFRESH, >>>> + NFEA_LOCKED, >>>> __NFEA_MAX >>>> }; >>> >>> Hmm, can you use NDA_FLAGS_EXT instead ? >>> That should simplify things and reduce the nl size. >>> >> >> I am using NDA_FDB_EXT_ATTRS. NFEA_LOCKED is just the >> flag as the other flags section is full wrt the normal flags, but maybe it >> doesn't fit in that section? >> > > Actually wait a second, this is completely wrong use of NDA_FDB_EXT_ATTRS. > That is a nested attribute, so the code below is wrong. More below.. > >> I will just note that iproute2 support for parsing nested attributes >> does not work, thus the BR_FDB_NOTIFY section (lines 150-165) are >> obsolete with respect to iproute2 as it is now. I cannot rule out that >> someone has some other tool that can handle this BR_FDB_NOTIFY, but I >> could not make iproute2 as it stands handle nested attributes. And of >> course there is no handling of NDA_FDB_EXT_ATTRS in iproute2 now. >> >>> #define NFEA_MAX (__NFEA_MAX - 1) >>>> diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c >>>> index 6ccda68bd473..396dcf3084cf 100644 >>>> --- a/net/bridge/br_fdb.c >>>> +++ b/net/bridge/br_fdb.c >>>> @@ -105,6 +105,7 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, >>>> struct nda_cacheinfo ci; >>>> struct nlmsghdr *nlh; >>>> struct ndmsg *ndm; >>>> + u8 ext_flags = 0; >>>> >>>> nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags); >>>> if (nlh == NULL) >>>> @@ -125,11 +126,16 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, >>>> ndm->ndm_flags |= NTF_EXT_LEARNED; >>>> if (test_bit(BR_FDB_STICKY, &fdb->flags)) >>>> ndm->ndm_flags |= NTF_STICKY; >>>> + if (test_bit(BR_FDB_ENTRY_LOCKED, &fdb->flags)) >>>> + ext_flags |= 1 << NFEA_LOCKED; >>>> >>>> if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr)) >>>> goto nla_put_failure; >>>> if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex)) >>>> goto nla_put_failure; >>>> + if (nla_put_u8(skb, NDA_FDB_EXT_ATTRS, ext_flags)) >>>> + goto nla_put_failure; >>>> + > > This is wrong. NDA_FDB_EXT_ATTRS is a nested attribute, you can't use it as a u8. > You need to have this structure: > [ NDA_FDB_EXT_ATTRS ] > ` [ NFEA_LOCKED ] > > But that's why I asked if you could use the NDA_FLAGS_EXT attribute. You can see > the logic from the neigh code.Ahh yes, NDA_FLAGS_EXT was not there in the 5.15.x kernel I have originally being making the patches in. I hope that the handling of nested attributes has been fixed in iproute2. ;-)> > Also note that you need to account for the new attribute's size in fdb_nlmsg_size(). > > >>>> ci.ndm_used = jiffies_to_clock_t(now - fdb->used); >>>> ci.ndm_confirmed = 0; >>>> ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated); >>>> diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c >>>> index e0c13fcc50ed..897908484b18 100644 >>>> --- a/net/bridge/br_input.c >>>> +++ b/net/bridge/br_input.c >>>> @@ -75,6 +75,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb >>>> struct net_bridge_mcast *brmctx; >>>> struct net_bridge_vlan *vlan; >>>> struct net_bridge *br; >>>> + unsigned long flags = 0; >>> >>> Please move this below... >>> >>>> u16 vid = 0; >>>> u8 state; >>>> >>>> @@ -94,8 +95,16 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb >>>> br_fdb_find_rcu(br, eth_hdr(skb)->h_source, vid); >>>> >>>> if (!fdb_src || READ_ONCE(fdb_src->dst) != p || >>>> - test_bit(BR_FDB_LOCAL, &fdb_src->flags)) >>>> + test_bit(BR_FDB_LOCAL, &fdb_src->flags)) { >>>> + if (!fdb_src) { >>> >>> ... here where it's only used. >>> >> >> Forgot that one. Shall do! >> >>>> + set_bit(BR_FDB_ENTRY_LOCKED, &flags); >>>> + br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, flags); >>>> + } >>>> goto drop; >>>> + } else { >>>> + if (test_bit(BR_FDB_ENTRY_LOCKED, &fdb_src->flags)) >>>> + goto drop; >>>> + } >>>> } >>>> >>>> nbp_switchdev_frame_mark(p, skb); >>>> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h >>>> index 48bc61ebc211..f5a0b68c4857 100644 >>>> --- a/net/bridge/br_private.h >>>> +++ b/net/bridge/br_private.h >>>> @@ -248,7 +248,8 @@ enum { >>>> BR_FDB_ADDED_BY_EXT_LEARN, >>>> BR_FDB_OFFLOADED, >>>> BR_FDB_NOTIFY, >>>> - BR_FDB_NOTIFY_INACTIVE >>>> + BR_FDB_NOTIFY_INACTIVE, >>>> + BR_FDB_ENTRY_LOCKED, >>>> }; >>>> >>>> struct net_bridge_fdb_key {