| Message ID | 20220222132818.1180786-1-schultz.hans+netdev@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Add support for locked bridge ports (for 802.1X) | expand |
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?
On tis, feb 22, 2022 at 11:15, Jakub Kicinski <kuba@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.
On Wed, 23 Feb 2022 09:40:59 +0100 Hans Schultz wrote: > > 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. Alright, thanks for clarifying! > 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.
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. Hans Schultz (5): net: bridge: Add support for bridge port in locked mode net: bridge: Add support for offloading of locked port flag net: dsa: Include BR_PORT_LOCKED in the list of synced brport flags net: dsa: mv88e6xxx: Add support for bridge port locked mode selftests: forwarding: tests of locked port feature drivers/net/dsa/mv88e6xxx/chip.c | 9 +- drivers/net/dsa/mv88e6xxx/port.c | 29 +++ drivers/net/dsa/mv88e6xxx/port.h | 9 +- include/linux/if_bridge.h | 1 + include/uapi/linux/if_link.h | 1 + net/bridge/br_input.c | 11 +- net/bridge/br_netlink.c | 6 +- net/bridge/br_switchdev.c | 2 +- net/dsa/port.c | 4 +- .../testing/selftests/net/forwarding/Makefile | 1 + .../net/forwarding/bridge_locked_port.sh | 180 ++++++++++++++++++ tools/testing/selftests/net/forwarding/lib.sh | 8 + 12 files changed, 254 insertions(+), 7 deletions(-) create mode 100755 tools/testing/selftests/net/forwarding/bridge_locked_port.sh