Jakub Kicinski
2022-Feb-22 19:15 UTC
[Bridge] [PATCH net-next v4 0/5] Add support for locked bridge ports (for 802.1X)
On Tue, 22 Feb 2022 14:28:13 +0100 Hans Schultz wrote:> This series starts by adding support for SA filtering to the bridge, > which is then allowed to be offloaded to switchdev devices. Furthermore > an offloading implementation is supplied for the mv88e6xxx driver. > > Public Local Area Networks are often deployed such that there is a > risk of unauthorized or unattended clients getting access to the LAN. > To prevent such access we introduce SA filtering, such that ports > designated as secure ports are set in locked mode, so that only > authorized source MAC addresses are given access by adding them to > the bridges forwarding database. Incoming packets with source MAC > addresses that are not in the forwarding database of the bridge are > discarded. It is then the task of user space daemons to populate the > bridge's forwarding database with static entries of authorized entities. > > The most common approach is to use the IEEE 802.1X protocol to take > care of the authorization of allowed users to gain access by opening > for the source address of the authorized host. > > With the current use of the bridge parameter in hostapd, there is > a limitation in using this for IEEE 802.1X port authentication. It > depends on hostapd attaching the port on which it has a successful > authentication to the bridge, but that only allows for a single > authentication per port. This patch set allows for the use of > IEEE 802.1X port authentication in a more general network context with > multiple 802.1X aware hosts behind a single port as depicted, which is > a commonly used commercial use-case, as it is only the number of > available entries in the forwarding database that limits the number of > authenticated clients. > > +--------------------------------+ > | | > | Bridge/Authenticator | > | | > +-------------+------------------+ > 802.1X port | > | > | > +------+-------+ > | | > | Hub/Switch | > | | > +-+----------+-+ > | | > +--+--+ +--+--+ > | | | | > Hosts | a | | b | . . . > | | | | > +-----+ +-----+ > > The 802.1X standard involves three different components, a Supplicant > (Host), an Authenticator (Network Access Point) and an Authentication > Server which is typically a Radius server. This patch set thus enables > the bridge module together with an authenticator application to serve > as an Authenticator on designated ports. > > > For the bridge to become an IEEE 802.1X Authenticator, a solution using > hostapd with the bridge driver can be found at > https://github.com/westermo/hostapd/tree/bridge_driver . > > > The relevant components work transparently in relation to if it is the > bridge module or the offloaded switchcore case that is in use.You still haven't answer my question. Is the data plane clear text in the deployment you describe?
Hans Schultz
2022-Feb-23 08:40 UTC
[Bridge] [PATCH net-next v4 0/5] Add support for locked bridge ports (for 802.1X)
On tis, feb 22, 2022 at 11:15, Jakub Kicinski <kuba at kernel.org> wrote:> On Tue, 22 Feb 2022 14:28:13 +0100 Hans Schultz wrote: >> This series starts by adding support for SA filtering to the bridge, >> which is then allowed to be offloaded to switchdev devices. Furthermore >> an offloading implementation is supplied for the mv88e6xxx driver. >> >> Public Local Area Networks are often deployed such that there is a >> risk of unauthorized or unattended clients getting access to the LAN. >> To prevent such access we introduce SA filtering, such that ports >> designated as secure ports are set in locked mode, so that only >> authorized source MAC addresses are given access by adding them to >> the bridges forwarding database. Incoming packets with source MAC >> addresses that are not in the forwarding database of the bridge are >> discarded. It is then the task of user space daemons to populate the >> bridge's forwarding database with static entries of authorized entities. >> >> The most common approach is to use the IEEE 802.1X protocol to take >> care of the authorization of allowed users to gain access by opening >> for the source address of the authorized host. >> >> With the current use of the bridge parameter in hostapd, there is >> a limitation in using this for IEEE 802.1X port authentication. It >> depends on hostapd attaching the port on which it has a successful >> authentication to the bridge, but that only allows for a single >> authentication per port. This patch set allows for the use of >> IEEE 802.1X port authentication in a more general network context with >> multiple 802.1X aware hosts behind a single port as depicted, which is >> a commonly used commercial use-case, as it is only the number of >> available entries in the forwarding database that limits the number of >> authenticated clients. >> >> +--------------------------------+ >> | | >> | Bridge/Authenticator | >> | | >> +-------------+------------------+ >> 802.1X port | >> | >> | >> +------+-------+ >> | | >> | Hub/Switch | >> | | >> +-+----------+-+ >> | | >> +--+--+ +--+--+ >> | | | | >> Hosts | a | | b | . . . >> | | | | >> +-----+ +-----+ >> >> The 802.1X standard involves three different components, a Supplicant >> (Host), an Authenticator (Network Access Point) and an Authentication >> Server which is typically a Radius server. This patch set thus enables >> the bridge module together with an authenticator application to serve >> as an Authenticator on designated ports. >> >> >> For the bridge to become an IEEE 802.1X Authenticator, a solution using >> hostapd with the bridge driver can be found at >> https://github.com/westermo/hostapd/tree/bridge_driver . >> >> >> The relevant components work transparently in relation to if it is the >> bridge module or the offloaded switchcore case that is in use. > > You still haven't answer my question. Is the data plane clear text in > the deployment you describe?Sorry, I didn't understand your question in the first instance. So as 802.1X is only about authentication/authorization, the port when opened for a host is like any other switch port and thus communication is in the clear. I have not looked much into macsec (but know ipsec), and that is a crypto (key) based connection mechanism, but that is a totally different ballgame, and I think it would for most practical cases require hardware encryption.