[PATCH v8 net-next 2/2] net: dsa: mv88e6xxx: mac-auth/MAB implementation

Hans J. Schultz
2022-11-12T20:38:57Z

This implementation for the Marvell mv88e6xxx chip series, is based on
handling ATU miss violations occurring when packets ingress on a port
that is locked with learning on. This will trigger a
SWITCHDEV_FDB_ADD_TO_BRIDGE event, that wil incurr the bridge module,
to add a locked FDB entry. This bridge FDB entry will not age out as
it has the extern_learn flag set.

Userspace daemons can listen to these events and either accept or deny
access for the host, by either replacing the locked FDB entry with a
simple entry or leave the locked entry.

If the host MAC address is already present on another port, a ATU
member violation will occur, but to no real effect. Statistics on these
violations can be shown with the command and example output of interest:

NIC statistics:
...
atu_member_violation: 36
atu_miss_violation: 23
...

Where ethX is the interface of the MAB enabled port.

Signed-off-by: Hans J. Schultz <netdev@kapio-technology.com>
---
drivers/net/dsa/mv88e6xxx/Makefile | 1 +
drivers/net/dsa/mv88e6xxx/chip.c | 19 ++++--
drivers/net/dsa/mv88e6xxx/chip.h | 10 ++++
drivers/net/dsa/mv88e6xxx/global1_atu.c | 10 +++-
drivers/net/dsa/mv88e6xxx/port.h | 6 ++
drivers/net/dsa/mv88e6xxx/switchdev.c | 77 +++++++++++++++++++++++++
drivers/net/dsa/mv88e6xxx/switchdev.h | 19 ++++++
7 files changed, 135 insertions(+), 7 deletions(-)
create mode 100644 drivers/net/dsa/mv88e6xxx/switchdev.c
create mode 100644 drivers/net/dsa/mv88e6xxx/switchdev.h

diff --git a/drivers/net/dsa/mv88e6xxx/Makefile b/drivers/net/dsa/mv88e6xxx/Makefile
index c8eca2b6f959..be903a983780 100644
--- a/drivers/net/dsa/mv88e6xxx/Makefile
+++ b/drivers/net/dsa/mv88e6xxx/Makefile
@@ -15,3 +15,4 @@ mv88e6xxx-objs += port_hidden.o
mv88e6xxx-$(CONFIG_NET_DSA_MV88E6XXX_PTP) += ptp.o
mv88e6xxx-objs += serdes.o
mv88e6xxx-objs += smi.o
+mv88e6xxx-objs += switchdev.o
diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index ccfa4751d3b7..efc0085a5616 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -1726,11 +1726,11 @@ static int mv88e6xxx_vtu_get(struct mv88e6xxx_chip *chip, u16 vid,
return err;
}

-static int mv88e6xxx_vtu_walk(struct mv88e6xxx_chip *chip,
- int (*cb)(struct mv88e6xxx_chip *chip,
- const struct mv88e6xxx_vtu_entry *entry,
- void *priv),
- void *priv)
+int mv88e6xxx_vtu_walk(struct mv88e6xxx_chip *chip,
+ int (*cb)(struct mv88e6xxx_chip *chip,
+ const struct mv88e6xxx_vtu_entry *entry,
+ void *priv),
+ void *priv)
{
struct mv88e6xxx_vtu_entry entry = {
.vid = mv88e6xxx_max_vid(chip),
@@ -6524,7 +6524,7 @@ static int mv88e6xxx_port_pre_bridge_flags(struct dsa_switch *ds, int port,
const struct mv88e6xxx_ops *ops;

if (flags.mask & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD |
- BR_BCAST_FLOOD | BR_PORT_LOCKED))
+ BR_BCAST_FLOOD | BR_PORT_LOCKED | BR_PORT_MAB))
return -EINVAL;

ops = chip->info->ops;
@@ -6582,12 +6582,19 @@ static int mv88e6xxx_port_bridge_flags(struct dsa_switch *ds, int port,
goto out;
}

+ if (flags.mask & BR_PORT_MAB) {
+ chip->ports[port].mab = !!(flags.val & BR_PORT_MAB);
+ err = 0;
+ }
+
if (flags.mask & BR_PORT_LOCKED) {
bool locked = !!(flags.val & BR_PORT_LOCKED);

err = mv88e6xxx_port_set_lock(chip, port, locked);
if (err)
goto out;
+
+ chip->ports[port].locked = locked;
}
out:
mv88e6xxx_reg_unlock(chip);
diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h
index e693154cf803..3b951cd0e6f8 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.h
+++ b/drivers/net/dsa/mv88e6xxx/chip.h
@@ -280,6 +280,10 @@ struct mv88e6xxx_port {
unsigned int serdes_irq;
char serdes_irq_name[64];
struct devlink_region *region;
+
+ /* Locked port and MacAuth control flags */
+ bool locked;
+ bool mab;
};

enum mv88e6xxx_region_id {
@@ -802,6 +806,12 @@ static inline void mv88e6xxx_reg_unlock(struct mv88e6xxx_chip *chip)
mutex_unlock(&chip->reg_lock);
}

+int mv88e6xxx_vtu_walk(struct mv88e6xxx_chip *chip,
+ int (*cb)(struct mv88e6xxx_chip *chip,
+ const struct mv88e6xxx_vtu_entry *entry,
+ void *priv),
+ void *priv);
+
int mv88e6xxx_fid_map(struct mv88e6xxx_chip *chip, unsigned long *bitmap);

#endif /* _MV88E6XXX_CHIP_H */
diff --git a/drivers/net/dsa/mv88e6xxx/global1_atu.c b/drivers/net/dsa/mv88e6xxx/global1_atu.c
index 8a874b6fc8e1..0a57f4e7dd46 100644
--- a/drivers/net/dsa/mv88e6xxx/global1_atu.c
+++ b/drivers/net/dsa/mv88e6xxx/global1_atu.c
@@ -12,6 +12,7 @@

#include "chip.h"
#include "global1.h"
+#include "switchdev.h"

/* Offset 0x01: ATU FID Register */

@@ -426,6 +427,8 @@ static irqreturn_t mv88e6xxx_g1_atu_prob_irq_thread_fn(int irq, void *dev_id)
if (err)
goto out;

+ mv88e6xxx_reg_unlock(chip);
+
spid = entry.state;

if (val & MV88E6XXX_G1_ATU_OP_AGE_OUT_VIOLATION) {
@@ -446,6 +449,12 @@ static irqreturn_t mv88e6xxx_g1_atu_prob_irq_thread_fn(int irq, void *dev_id)
"ATU miss violation for %pM portvec %x spid %d\n",
entry.mac, entry.portvec, spid);
chip->ports[spid].atu_miss_violation++;
+
+ if (fid && chip->ports[spid].mab)
+ err = mv88e6xxx_handle_violation(chip, spid, &entry,
+ fid, MV88E6XXX_G1_ATU_OP_MISS_VIOLATION);
+ if (err)
+ goto out;
}

if (val & MV88E6XXX_G1_ATU_OP_FULL_VIOLATION) {
@@ -454,7 +463,6 @@ static irqreturn_t mv88e6xxx_g1_atu_prob_irq_thread_fn(int irq, void *dev_id)
entry.mac, entry.portvec, spid);
chip->ports[spid].atu_full_violation++;
}
- mv88e6xxx_reg_unlock(chip);

return IRQ_HANDLED;

diff --git a/drivers/net/dsa/mv88e6xxx/port.h b/drivers/net/dsa/mv88e6xxx/port.h
index aec9d4fd20e3..bd90a02865a0 100644
--- a/drivers/net/dsa/mv88e6xxx/port.h
+++ b/drivers/net/dsa/mv88e6xxx/port.h
@@ -377,6 +377,12 @@ int mv88e6xxx_port_set_pvid(struct mv88e6xxx_chip *chip, int port, u16 pvid);
int mv88e6xxx_port_set_lock(struct mv88e6xxx_chip *chip, int port,
bool locked);

+static inline bool mv88e6xxx_port_is_locked(struct mv88e6xxx_chip *chip,
+ int port)
+{
+ return chip->ports[port].locked;
+}
+
int mv88e6xxx_port_set_8021q_mode(struct mv88e6xxx_chip *chip, int port,
u16 mode);
int mv88e6095_port_tag_remap(struct mv88e6xxx_chip *chip, int port);
diff --git a/drivers/net/dsa/mv88e6xxx/switchdev.c b/drivers/net/dsa/mv88e6xxx/switchdev.c
new file mode 100644
index 000000000000..000778550532
--- /dev/null
+++ b/drivers/net/dsa/mv88e6xxx/switchdev.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * switchdev.c
+ *
+ * Authors:
+ * Hans J. Schultz <hans.schultz@westermo.com>
+ *
+ */
+
+#include <net/switchdev.h>
+#include "chip.h"
+#include "global1.h"
+
+struct mv88e6xxx_fid_search_ctx {
+ u16 fid_search;
+ u16 vid_found;
+};
+
+static int mv88e6xxx_find_vid(struct mv88e6xxx_chip *chip,
+ const struct mv88e6xxx_vtu_entry *entry,
+ void *priv)
+{
+ struct mv88e6xxx_fid_search_ctx *ctx = priv;
+
+ if (ctx->fid_search == entry->fid) {
+ ctx->vid_found = entry->vid;
+ return 1;
+ }
+
+ return 0;
+}
+
+int mv88e6xxx_handle_violation(struct mv88e6xxx_chip *chip, int port,
+ struct mv88e6xxx_atu_entry *entry,
+ u16 fid, u16 type)
+{
+ struct switchdev_notifier_fdb_info info = {
+ .addr = entry->mac,
+ .locked = true,
+ };
+ struct mv88e6xxx_fid_search_ctx ctx;
+ struct net_device *brport;
+ struct dsa_port *dp;
+ int err;
+
+ if (mv88e6xxx_is_invalid_port(chip, port))
+ return -ENODEV;
+
+ ctx.fid_search = fid;
+ mv88e6xxx_reg_lock(chip);
+ err = mv88e6xxx_vtu_walk(chip, mv88e6xxx_find_vid, &ctx);
+ mv88e6xxx_reg_unlock(chip);
+ if (err < 0)
+ return err;
+ if (err == 1)
+ info.vid = ctx.vid_found;
+ else
+ return -ENODATA;
+
+ switch (type) {
+ case MV88E6XXX_G1_ATU_OP_MISS_VIOLATION:
+ dp = dsa_to_port(chip->ds, port);
+
+ rtnl_lock();
+ brport = dsa_port_to_bridge_port(dp);
+ if (!brport) {
+ rtnl_unlock();
+ return -ENODEV;
+ }
+ err = call_switchdev_notifiers(SWITCHDEV_FDB_ADD_TO_BRIDGE,
+ brport, &info.info, NULL);
+ rtnl_unlock();
+ break;
+ }
+
+ return err;
+}
diff --git a/drivers/net/dsa/mv88e6xxx/switchdev.h b/drivers/net/dsa/mv88e6xxx/switchdev.h
new file mode 100644
index 000000000000..ccc10a9d4072
--- /dev/null
+++ b/drivers/net/dsa/mv88e6xxx/switchdev.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * switchdev.h
+ *
+ * Authors:
+ * Hans J. Schultz <hans.schultz@westermo.com>
+ *
+ */
+
+#ifndef DRIVERS_NET_DSA_MV88E6XXX_SWITCHDEV_H_
+#define DRIVERS_NET_DSA_MV88E6XXX_SWITCHDEV_H_
+
+#include "chip.h"
+
+int mv88e6xxx_handle_violation(struct mv88e6xxx_chip *chip, int port,
+ struct mv88e6xxx_atu_entry *entry,
+ u16 fid, u16 type);
+
+#endif /* DRIVERS_NET_DSA_MV88E6XXX_SWITCHDEV_H_ */
--
2.34.1