Commit 27cf76fe authored by Petr Machata's avatar Petr Machata Committed by David S. Miller

mlxsw: spectrum_span: Support mirror to gretap

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: default avatarPetr Machata <petrm@mellanox.com>
Reviewed-by: default avatarIdo Schimmel <idosch@mellanox.com>
Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 52a6444c
......@@ -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
......
/*
* drivers/net/ethernet/mellanox/mlxsw/mlxsw_span.c
* Copyright (c) 2018 Mellanox Technologies. All rights reserved.
* Copyright (c) 2018 Petr Machata <petrm@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
......
......@@ -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;
......
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