From 27cf76fe60ec6fbe2ba8844261b90a6aecbc42f0 Mon Sep 17 00:00:00 2001 From: Petr Machata Date: Tue, 27 Feb 2018 14:53:48 +0100 Subject: [PATCH] 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: Petr Machata Reviewed-by: Ido Schimmel Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- 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 * * 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 +#include +#include #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 +#include + +#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; -- 2.11.0