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 {
Nikolay Aleksandrov
2022-Mar-10 16:14 UTC
[Bridge] [PATCH net-next 1/3] net: bridge: add fdb flag to extent locked port feature
On 10/03/2022 18:11, Hans Schultz wrote:> 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. ;-) >It hasn't been broken, I'm guessing you're having issues with the nested bit being set. Check NLA_F_NESTED and NLA_TYPE_MASK.>> >> 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 {