net: mscc: ocelot: deal with problematic MAC_ETYPE VCAP IS2 rules

By default, the VCAP IS2 will produce a single match for each frame, on
the most specific classification.

Example: a ping packet (ICMP over IPv4 over Ethernet) sent from an IP
address of 10.0.0.1 and a MAC address of 96:18:82:00:04:01 will match
this rule:

tc filter add dev swp0 ingress protocol ipv4 \
	flower skip_sw src_ip 10.0.0.1 action drop

but not this one:

tc filter add dev swp0 ingress \
	flower skip_sw src_mac 96:18:82:00:04:01 action drop

Currently the driver does not really warn the user in any way about
this, and the behavior is rather strange anyway.

The current patch is a workaround to force matches on MAC_ETYPE keys
(DMAC and SMAC) for all packets irrespective of higher layer protocol.
The setting is made at the port level.

Of course this breaks all other non-src_mac and non-dst_mac matches, so
rule exclusivity checks have been added to the driver, in order to never
have rules of both types on any ingress port.

The bits that discard higher-level protocol information are set only
once a MAC_ETYPE rule is added to a filter block, and only for the ports
that are bound to that filter block. Then all further non-MAC_ETYPE
rules added to that filter block should be denied by the ports bound to
it.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mscc/ocelot_ace.c b/drivers/net/ethernet/mscc/ocelot_ace.c
index 3bd28604448043a73c54928e6907501ccd4d0b71..8a2f7d13ef6da6db1262e3365d0e35cf3cd88769 100644 (file)
--- a/drivers/net/ethernet/mscc/ocelot_ace.c
+++ b/drivers/net/ethernet/mscc/ocelot_ace.c
@@ -706,13 +706,114 @@ ocelot_ace_rule_get_rule_index(struct ocelot_acl_block *block, int index)
        return NULL;
 }
 
+/* If @on=false, then SNAP, ARP, IP and OAM frames will not match on keys based
+ * on destination and source MAC addresses, but only on higher-level protocol
+ * information. The only frame types to match on keys containing MAC addresses
+ * in this case are non-SNAP, non-ARP, non-IP and non-OAM frames.
+ *
+ * If @on=true, then the above frame types (SNAP, ARP, IP and OAM) will match
+ * on MAC_ETYPE keys such as destination and source MAC on this ingress port.
+ * However the setting has the side effect of making these frames not matching
+ * on any _other_ keys than MAC_ETYPE ones.
+ */
+static void ocelot_match_all_as_mac_etype(struct ocelot *ocelot, int port,
+                                         bool on)
+{
+       u32 val = 0;
+
+       if (on)
+               val = ANA_PORT_VCAP_S2_CFG_S2_SNAP_DIS(3) |
+                     ANA_PORT_VCAP_S2_CFG_S2_ARP_DIS(3) |
+                     ANA_PORT_VCAP_S2_CFG_S2_IP_TCPUDP_DIS(3) |
+                     ANA_PORT_VCAP_S2_CFG_S2_IP_OTHER_DIS(3) |
+                     ANA_PORT_VCAP_S2_CFG_S2_OAM_DIS(3);
+
+       ocelot_rmw_gix(ocelot, val,
+                      ANA_PORT_VCAP_S2_CFG_S2_SNAP_DIS_M |
+                      ANA_PORT_VCAP_S2_CFG_S2_ARP_DIS_M |
+                      ANA_PORT_VCAP_S2_CFG_S2_IP_TCPUDP_DIS_M |
+                      ANA_PORT_VCAP_S2_CFG_S2_IP_OTHER_DIS_M |
+                      ANA_PORT_VCAP_S2_CFG_S2_OAM_DIS_M,
+                      ANA_PORT_VCAP_S2_CFG, port);
+}
+
+static bool ocelot_ace_is_problematic_mac_etype(struct ocelot_ace_rule *ace)
+{
+       if (ace->type != OCELOT_ACE_TYPE_ETYPE)
+               return false;
+       if (ether_addr_to_u64(ace->frame.etype.dmac.value) &
+           ether_addr_to_u64(ace->frame.etype.dmac.mask))
+               return true;
+       if (ether_addr_to_u64(ace->frame.etype.smac.value) &
+           ether_addr_to_u64(ace->frame.etype.smac.mask))
+               return true;
+       return false;
+}
+
+static bool ocelot_ace_is_problematic_non_mac_etype(struct ocelot_ace_rule *ace)
+{
+       if (ace->type == OCELOT_ACE_TYPE_SNAP)
+               return true;
+       if (ace->type == OCELOT_ACE_TYPE_ARP)
+               return true;
+       if (ace->type == OCELOT_ACE_TYPE_IPV4)
+               return true;
+       if (ace->type == OCELOT_ACE_TYPE_IPV6)
+               return true;
+       return false;
+}
+
+static bool ocelot_exclusive_mac_etype_ace_rules(struct ocelot *ocelot,
+                                                struct ocelot_ace_rule *ace)
+{
+       struct ocelot_acl_block *block = &ocelot->acl_block;
+       struct ocelot_ace_rule *tmp;
+       unsigned long port;
+       int i;
+
+       if (ocelot_ace_is_problematic_mac_etype(ace)) {
+               /* Search for any non-MAC_ETYPE rules on the port */
+               for (i = 0; i < block->count; i++) {
+                       tmp = ocelot_ace_rule_get_rule_index(block, i);
+                       if (tmp->ingress_port_mask & ace->ingress_port_mask &&
+                           ocelot_ace_is_problematic_non_mac_etype(tmp))
+                               return false;
+               }
+
+               for_each_set_bit(port, &ace->ingress_port_mask,
+                                ocelot->num_phys_ports)
+                       ocelot_match_all_as_mac_etype(ocelot, port, true);
+       } else if (ocelot_ace_is_problematic_non_mac_etype(ace)) {
+               /* Search for any MAC_ETYPE rules on the port */
+               for (i = 0; i < block->count; i++) {
+                       tmp = ocelot_ace_rule_get_rule_index(block, i);
+                       if (tmp->ingress_port_mask & ace->ingress_port_mask &&
+                           ocelot_ace_is_problematic_mac_etype(tmp))
+                               return false;
+               }
+
+               for_each_set_bit(port, &ace->ingress_port_mask,
+                                ocelot->num_phys_ports)
+                       ocelot_match_all_as_mac_etype(ocelot, port, false);
+       }
+
+       return true;
+}
+
 int ocelot_ace_rule_offload_add(struct ocelot *ocelot,
-                               struct ocelot_ace_rule *rule)
+                               struct ocelot_ace_rule *rule,
+                               struct netlink_ext_ack *extack)
 {
        struct ocelot_acl_block *block = &ocelot->acl_block;
        struct ocelot_ace_rule *ace;
        int i, index;
 
+       if (!ocelot_exclusive_mac_etype_ace_rules(ocelot, rule)) {
+               NL_SET_ERR_MSG_MOD(extack,
+                                  "Cannot mix MAC_ETYPE with non-MAC_ETYPE rules");
+               return -EBUSY;
+       }
+
        /* Add rule to the linked list */
        ocelot_ace_rule_add(ocelot, block, rule);
 

diff --git a/drivers/net/ethernet/mscc/ocelot_ace.h b/drivers/net/ethernet/mscc/ocelot_ace.h
index 29d22c5667865bc664afa1471c5e040d8de7af1c..099e177f26173129cd5153ebcd291ee97644c966 100644 (file)
--- a/drivers/net/ethernet/mscc/ocelot_ace.h
+++ b/drivers/net/ethernet/mscc/ocelot_ace.h
@@ -194,7 +194,7 @@ struct ocelot_ace_rule {
 
        enum ocelot_ace_action action;
        struct ocelot_ace_stats stats;
-       u16 ingress_port_mask;
+       unsigned long ingress_port_mask;
 
        enum ocelot_vcap_bit dmac_mc;
        enum ocelot_vcap_bit dmac_bc;
@@ -215,7 +215,8 @@ struct ocelot_ace_rule {
 };
 
 int ocelot_ace_rule_offload_add(struct ocelot *ocelot,
-                               struct ocelot_ace_rule *rule);
+                               struct ocelot_ace_rule *rule,
+                               struct netlink_ext_ack *extack);
 int ocelot_ace_rule_offload_del(struct ocelot *ocelot,
                                struct ocelot_ace_rule *rule);
 int ocelot_ace_rule_stats_update(struct ocelot *ocelot,

diff --git a/drivers/net/ethernet/mscc/ocelot_flower.c b/drivers/net/ethernet/mscc/ocelot_flower.c
index 341923311fec3ad783efa929cdd0cabe481d85aa..954cb67eeaa2ddf28f8fa4756c624e49ab36a2f4 100644 (file)
--- a/drivers/net/ethernet/mscc/ocelot_flower.c
+++ b/drivers/net/ethernet/mscc/ocelot_flower.c
@@ -205,7 +205,7 @@ int ocelot_cls_flower_replace(struct ocelot *ocelot, int port,
                return ret;
        }
 
-       return ocelot_ace_rule_offload_add(ocelot, ace);
+       return ocelot_ace_rule_offload_add(ocelot, ace, f->common.extack);
 }
 EXPORT_SYMBOL_GPL(ocelot_cls_flower_replace);