From: Petr Machata <pe...@mellanox.com>
When a user requests mirror from a mlxsw physical port (possibly based
on an ACL match) to a gretap netdevice, the driver needs to resolve the
request to a particular physical port that the mirrored packets will
egress through, and a suite of configuration keys (importantly, IP and
MAC addresses). That means calling into routing and neighbor kernel code
to simulate the decisions made by the system for packets passing through
a gretap netdevice.
Add a new instance of mlxsw_sp_span_entry_ops to support this.
Signed-off-by: Petr Machata <pe...@mellanox.com>
Reviewed-by: Ido Schimmel <ido...@mellanox.com>
Signed-off-by: Jiri Pirko <j...@mellanox.com>
---
drivers/net/ethernet/mellanox/mlxsw/Kconfig | 2 +
.../net/ethernet/mellanox/mlxsw/spectrum_span.c | 167 ++++++++++++++++++++-
.../net/ethernet/mellanox/mlxsw/spectrum_span.h | 8 +
3 files changed, 175 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/Kconfig
b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
index d56eea310509..830c3e28505e 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
@@ -78,6 +78,8 @@ config MLXSW_SPECTRUM
depends on IPV6 || IPV6=n
select PARMAN
select MLXFW
+ depends on NET_IPGRE
+ depends on !(MLXSW_CORE=y && NET_IPGRE=m)
default m
---help---
This driver supports Mellanox Technologies Spectrum Ethernet
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
index 57df57c7a405..d5fda4f13c31 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.c
@@ -1,6 +1,7 @@
/*
* drivers/net/ethernet/mellanox/mlxsw/mlxsw_span.c
* Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2018 Petr Machata <pe...@mellanox.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -32,9 +33,12 @@
*/
#include <linux/list.h>
+#include <net/arp.h>
+#include <net/gre.h>
#include "spectrum.h"
#include "spectrum_span.h"
+#include "spectrum_ipip.h"
int mlxsw_sp_span_init(struct mlxsw_sp *mlxsw_sp)
{
@@ -127,17 +131,176 @@ struct mlxsw_sp_span_entry_ops
mlxsw_sp_span_entry_ops_phys = {
.deconfigure = mlxsw_sp_span_entry_phys_deconfigure,
};
+static struct net_device *
+mlxsw_sp_span_gretap4_route(const struct net_device *to_dev,
+ __be32 *saddrp, __be32 *daddrp)
+{
+ struct ip_tunnel *tun = netdev_priv(to_dev);
+ struct net_device *dev = NULL;
+ struct ip_tunnel_parm parms;
+ struct rtable *rt = NULL;
+ struct flowi4 fl4;
+
+ /* We assume "dev" stays valid after rt is put. */
+ ASSERT_RTNL();
+
+ parms = mlxsw_sp_ipip_netdev_parms4(to_dev);
+ ip_tunnel_init_flow(&fl4, parms.iph.protocol, *daddrp, *saddrp,
+ 0, 0, parms.link, tun->fwmark);
+
+ rt = ip_route_output_key(tun->net, &fl4);
+ if (IS_ERR(rt))
+ return NULL;
+
+ if (rt->rt_type != RTN_UNICAST)
+ goto out;
+
+ dev = rt->dst.dev;
+ *saddrp = fl4.saddr;
+ *daddrp = rt->rt_gateway;
+
+out:
+ ip_rt_put(rt);
+ return dev;
+}
+
+static int mlxsw_sp_span_dmac(struct neigh_table *tbl,
+ const void *pkey,
+ struct net_device *l3edev,
+ unsigned char dmac[ETH_ALEN])
+{
+ struct neighbour *neigh = neigh_lookup(tbl, pkey, l3edev);
+ int err = 0;
+
+ if (!neigh) {
+ neigh = neigh_create(tbl, pkey, l3edev);
+ if (IS_ERR(neigh))
+ return PTR_ERR(neigh);
+ }
+
+ neigh_event_send(neigh, NULL);
+
+ read_lock_bh(&neigh->lock);
+ if ((neigh->nud_state & NUD_VALID) && !neigh->dead)
+ memcpy(dmac, neigh->ha, ETH_ALEN);
+ else
+ err = -ENOENT;
+ read_unlock_bh(&neigh->lock);
+
+ neigh_release(neigh);
+ return err;
+}
+
+static int
+mlxsw_sp_span_entry_unoffloadable(struct mlxsw_sp_span_parms *sparmsp)
+{
+ sparmsp->dest_port = NULL;
+ return 0;
+}
+
+static int
+mlxsw_sp_span_entry_tunnel_parms_common(struct net_device *l3edev,
+ union mlxsw_sp_l3addr saddr,
+ union mlxsw_sp_l3addr daddr,
+ union mlxsw_sp_l3addr gw,
+ __u8 ttl,
+ struct neigh_table *tbl,
+ struct mlxsw_sp_span_parms *sparmsp)
+{
+ unsigned char dmac[ETH_ALEN];
+
+ if (mlxsw_sp_l3addr_is_zero(gw))
+ gw = daddr;
+
+ if (!l3edev || !mlxsw_sp_port_dev_check(l3edev) ||
+ mlxsw_sp_span_dmac(tbl, &gw, l3edev, dmac))
+ return mlxsw_sp_span_entry_unoffloadable(sparmsp);
+
+ sparmsp->dest_port = netdev_priv(l3edev);
+ sparmsp->ttl = ttl;
+ memcpy(sparmsp->dmac, dmac, ETH_ALEN);
+ memcpy(sparmsp->smac, l3edev->dev_addr, ETH_ALEN);
+ sparmsp->saddr = saddr;
+ sparmsp->daddr = daddr;
+ return 0;
+}
+
+static int
+mlxsw_sp_span_entry_gretap4_parms(const struct net_device *to_dev,
+ struct mlxsw_sp_span_parms *sparmsp)
+{
+ struct ip_tunnel_parm tparm = mlxsw_sp_ipip_netdev_parms4(to_dev);
+ union mlxsw_sp_l3addr saddr = { .addr4 = tparm.iph.saddr };
+ union mlxsw_sp_l3addr daddr = { .addr4 = tparm.iph.daddr };
+ bool inherit_tos = tparm.iph.tos & 0x1;
+ bool inherit_ttl = !tparm.iph.ttl;
+ union mlxsw_sp_l3addr gw = daddr;
+ struct net_device *l3edev;
+
+ if (!(to_dev->flags & IFF_UP) ||
+ /* Reject tunnels with GRE keys, checksums, etc. */
+ tparm.i_flags || tparm.o_flags ||
+ /* Require a fixed TTL and a TOS copied from the mirrored packet. */
+ inherit_ttl || !inherit_tos ||
+ /* A destination address may not be "any". */
+ mlxsw_sp_l3addr_is_zero(daddr))
+ return mlxsw_sp_span_entry_unoffloadable(sparmsp);
+
+ l3edev = mlxsw_sp_span_gretap4_route(to_dev, &saddr.addr4, &gw.addr4);
+ return mlxsw_sp_span_entry_tunnel_parms_common(l3edev, saddr, daddr, gw,
+ tparm.iph.ttl,
+ &arp_tbl, sparmsp);
+}
+
+static int
+mlxsw_sp_span_entry_gretap4_configure(struct mlxsw_sp_span_entry *span_entry,
+ struct mlxsw_sp_span_parms sparms)
+{
+ struct mlxsw_sp_port *dest_port = sparms.dest_port;
+ struct mlxsw_sp *mlxsw_sp = dest_port->mlxsw_sp;
+ u8 local_port = dest_port->local_port;
+ char mpat_pl[MLXSW_REG_MPAT_LEN];
+ int pa_id = span_entry->id;
+
+ /* Create a new port analayzer entry for local_port. */
+ mlxsw_reg_mpat_pack(mpat_pl, pa_id, local_port, true,
+ MLXSW_REG_MPAT_SPAN_TYPE_REMOTE_ETH_L3);
+ mlxsw_reg_mpat_eth_rspan_l2_pack(mpat_pl,
+ MLXSW_REG_MPAT_ETH_RSPAN_VERSION_NO_HEADER,
+ sparms.dmac, false);
+ mlxsw_reg_mpat_eth_rspan_l3_ipv4_pack(mpat_pl,
+ sparms.ttl, sparms.smac,
+ be32_to_cpu(sparms.saddr.addr4),
+ be32_to_cpu(sparms.daddr.addr4));
+
+ return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(mpat), mpat_pl);
+}
+
+static void
+mlxsw_sp_span_entry_gretap4_deconfigure(struct mlxsw_sp_span_entry *span_entry)
+{
+ mlxsw_sp_span_entry_deconfigure_common(span_entry,
+ MLXSW_REG_MPAT_SPAN_TYPE_REMOTE_ETH_L3);
+}
+
+static const struct mlxsw_sp_span_entry_ops mlxsw_sp_span_entry_ops_gretap4 = {
+ .can_handle = is_gretap_dev,
+ .parms = mlxsw_sp_span_entry_gretap4_parms,
+ .configure = mlxsw_sp_span_entry_gretap4_configure,
+ .deconfigure = mlxsw_sp_span_entry_gretap4_deconfigure,
+};
+
static const
struct mlxsw_sp_span_entry_ops *const mlxsw_sp_span_entry_types[] = {
&mlxsw_sp_span_entry_ops_phys,
+ &mlxsw_sp_span_entry_ops_gretap4,
};
static int
mlxsw_sp_span_entry_nop_parms(const struct net_device *to_dev,
struct mlxsw_sp_span_parms *sparmsp)
{
- sparmsp->dest_port = NULL;
- return 0;
+ return mlxsw_sp_span_entry_unoffloadable(sparmsp);
}
static int
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
index b6dcd7d7277c..948aceb512c5 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_span.h
@@ -35,6 +35,9 @@
#define _MLXSW_SPECTRUM_SPAN_H
#include <linux/types.h>
+#include <linux/if_ether.h>
+
+#include "spectrum_router.h"
struct mlxsw_sp;
struct mlxsw_sp_port;
@@ -52,6 +55,11 @@ struct mlxsw_sp_span_inspected_port {
struct mlxsw_sp_span_parms {
struct mlxsw_sp_port *dest_port; /* NULL for unoffloaded SPAN. */
+ unsigned int ttl;
+ unsigned char dmac[ETH_ALEN];
+ unsigned char smac[ETH_ALEN];
+ union mlxsw_sp_l3addr daddr;
+ union mlxsw_sp_l3addr saddr;
};
struct mlxsw_sp_span_entry_ops;
--
2.14.3
