Nexthops for MPLS routes have a via address field sized for the
largest via address that is expected, which is 32 bytes. This means
that in the most common case of having ipv4 via addresses, 28 bytes of
memory more than required are used per nexthop. In the other common
case of an ipv6 nexthop then 16 bytes more than required are
used. With large numbers of MPLS routes this extra memory usage could
start to become significant.
To avoid allocating memory for a maximum length via address when not
all of it is required and to allow for ease of iterating over
nexthops, then the via addresses are changed to be stored in the same
memory block as the route and nexthops, but in an array after the end
of the array of nexthops. New accessors are provided to retrieve a
pointer to the via address.
To allow for O(1) access without having to store a pointer or offset
per nh, the via address for each nexthop is sized according to the
maximum via address for any nexthop in the route, which is stored in a
new route field, rt_max_alen, but this is in an existing hole in
struct mpls_route so it doesn't increase the size of the
structure. Each via address is ensured to be aligned to VIA_ALEN_ALIGN
to account for architectures that don't allow unaligned accesses.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fill in the via address length for the predefined IPv4 and IPv6
explicit-null label routes.
Fixes: f8efb73c97 ("mpls: multipath route support")
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the selection of a multipath route to use a flow-based
hash. This more suitable for traffic sensitive to reordering within a
flow (e.g. TCP, L2VPN) and whilst still allowing a good distribution
of traffic given enough flows.
Selection of the path for a multipath route is done using a hash of:
1. Label stack up to MAX_MP_SELECT_LABELS labels or up to and
including entropy label, whichever is first.
2. 3-tuple of (L3 src, L3 dst, proto) from IPv4/IPv6 header in MPLS
payload, if present.
Naturally, a 5-tuple hash using L4 information in addition would be
possible and be better in some scenarios, but there is a tradeoff
between looking deeper into the packet to achieve good distribution,
and packet forwarding performance, and I have erred on the side of the
latter as the default.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for MPLS multipath routes.
Includes following changes to support multipath:
- splits struct mpls_route into 'struct mpls_route + struct mpls_nh'
- 'struct mpls_nh' represents a mpls nexthop label forwarding entry
- moves mpls route and nexthop structures into internal.h
- A mpls_route can point to multiple mpls_nh structs
- the nexthops are maintained as a array (similar to ipv4 fib)
- In the process of restructuring, this patch also consistently changes
all labels to u8
- Adds support to parse/fill RTA_MULTIPATH netlink attribute for
multipath routes similar to ipv4/v6 fib
- In this patch, the multipath route nexthop selection algorithm
simply returns the first nexthop. It is replaced by a
hash based algorithm from Robert Shearman in the next patch
- mpls_route_update cleanup: remove 'dev' handling in mpls_route_update.
mpls_route_update though implemented to update based on dev, it was
never used that way. And the dev handling gets tricky with multiple
nexthops. Cannot match against any single nexthops dev. So, this patch
removes the unused 'dev' handling in mpls_route_update.
- dead route/path handling will be implemented in a subsequent patch
Example:
$ip -f mpls route add 100 nexthop as 200 via inet 10.1.1.2 dev swp1 \
nexthop as 700 via inet 10.1.1.6 dev swp2 \
nexthop as 800 via inet 40.1.1.2 dev swp3
$ip -f mpls route show
100
nexthop as to 200 via inet 10.1.1.2 dev swp1
nexthop as to 700 via inet 10.1.1.6 dev swp2
nexthop as to 800 via inet 40.1.1.2 dev swp3
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The network namespace is already passed into dst_output pass it into
dst->output lwt->output and friends.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a memory leak in the mpls netns init function in case of failure. If
register_net_sysctl fails then we need to free the ctl_table.
Fixes: 7720c01f3f ("mpls: Add a sysctl to control the size of the mpls label table")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add cfg and family arguments to lwt build state functions. cfg is a void
pointer and will either be a pointer to a fib_config or fib6_config
structure. The family parameter indicates which one (either AF_INET
or AF_INET6).
LWT encpasulation implementation may use the fib configuration to build
the LWT state.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the lwtunnel state resides in per-protocol data. This is
a problem if we encapsulate ipv6 traffic in an ipv4 tunnel (or vice versa).
The xmit function of the tunnel does not know whether the packet has been
routed to it by ipv4 or ipv6, yet it needs the lwtstate data. Moving the
lwtstate data to dst_entry makes such inter-protocol tunneling possible.
As a bonus, this brings a nice diffstat.
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC 4182 s2 states that if an IPv4 Explicit NULL label is the only
label on the stack, then after popping the resulting packet must be
treated as a IPv4 packet and forwarded based on the IPv4 header. The
same is true for IPv6 Explicit NULL with an IPv6 packet following.
Therefore, when installing the IPv4/IPv6 Explicit NULL label routes,
add an attribute that specifies the expected payload type for use at
forwarding time for determining the type of the encapsulated packet
instead of inspecting the first nibble of the packet.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds null dev check for the 'cfg->rc_via_table ==
NEIGH_LINK_TABLE or dev_get_by_index() failed' case
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We recently changed this code from returning NULL to returning ERR_PTR.
There are some left over NULL assignments which we can remove. We can
preserve the error code from ip_route_output() instead of always
returning -ENODEV. Also these functions use a mix of gotos and direct
returns. There is no cleanup necessary so I changed the gotos to
direct returns.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In multiple locations there are checks for whether the label in hand
is a reserved label or not using the arbritray value of 16. Factor
this out into a #define for better maintainability and for
documentation.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Undefined reference to ip6_route_output and ip_route_output
was reported with CONFIG_INET=n and CONFIG_IPV6=n.
This patch uses ipv6_stub_impl.ipv6_dst_lookup instead of
ip6_route_output. And wraps affected code under
IS_ENABLED(CONFIG_INET) and IS_ENABLED(CONFIG_IPV6).
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fix for:
net/mpls/mpls_iptunnel.c:73:19: sparse: incompatible types in comparison
expression (different address spaces)
remove incorrect rcu_dereference possibly left over from
earlier revisions of the code.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If user did not specify an oif, try and get it from the via address.
If failed to get device, return with -ENODEV.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This implementation uses lwtunnel infrastructure to register
hooks for mpls tunnel encaps.
It picks cues from iptunnel_encaps infrastructure and previous
mpls iptunnel RFC patches from Eric W. Biederman and Robert Shearman
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If a device is renamed and the original name is subsequently reused
for a new device, the following warning is generated:
sysctl duplicate entry: /net/mpls/conf/veth0//input
CPU: 3 PID: 1379 Comm: ip Not tainted 4.1.0-rc4+ #20
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
0000000000000000 0000000000000000 ffffffff81566aaf 0000000000000000
ffffffff81236279 ffff88002f7d7f00 0000000000000000 ffff88000db336d8
ffff88000db33698 0000000000000005 ffff88002e046000 ffff8800168c9280
Call Trace:
[<ffffffff81566aaf>] ? dump_stack+0x40/0x50
[<ffffffff81236279>] ? __register_sysctl_table+0x289/0x5a0
[<ffffffffa051a24f>] ? mpls_dev_notify+0x1ff/0x300 [mpls_router]
[<ffffffff8108db7f>] ? notifier_call_chain+0x4f/0x70
[<ffffffff81470e72>] ? register_netdevice+0x2b2/0x480
[<ffffffffa0524748>] ? veth_newlink+0x178/0x2d3 [veth]
[<ffffffff8147f84c>] ? rtnl_newlink+0x73c/0x8e0
[<ffffffff8147f27a>] ? rtnl_newlink+0x16a/0x8e0
[<ffffffff81459ff2>] ? __kmalloc_reserve.isra.30+0x32/0x90
[<ffffffff8147ccfd>] ? rtnetlink_rcv_msg+0x8d/0x250
[<ffffffff8145b027>] ? __alloc_skb+0x47/0x1f0
[<ffffffff8149badb>] ? __netlink_lookup+0xab/0xe0
[<ffffffff8147cc70>] ? rtnetlink_rcv+0x30/0x30
[<ffffffff8149e7a0>] ? netlink_rcv_skb+0xb0/0xd0
[<ffffffff8147cc64>] ? rtnetlink_rcv+0x24/0x30
[<ffffffff8149df17>] ? netlink_unicast+0x107/0x1a0
[<ffffffff8149e4be>] ? netlink_sendmsg+0x50e/0x630
[<ffffffff8145209c>] ? sock_sendmsg+0x3c/0x50
[<ffffffff81452beb>] ? ___sys_sendmsg+0x27b/0x290
[<ffffffff811bd258>] ? mem_cgroup_try_charge+0x88/0x110
[<ffffffff811bd5b6>] ? mem_cgroup_commit_charge+0x56/0xa0
[<ffffffff811d7700>] ? do_filp_open+0x30/0xa0
[<ffffffff8145336e>] ? __sys_sendmsg+0x3e/0x80
[<ffffffff8156c3f2>] ? system_call_fastpath+0x16/0x75
Fix this by unregistering the previous sysctl table (registered for
the path containing the original device name) and re-registering the
table for the path containing the new device name.
Fixes: 37bde79979 ("mpls: Per-device enabling of packet input")
Reported-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The mpls device is used in an RCU read context without a lock being
held. As the memory is freed without waiting for the RCU grace period
to elapse, the freed memory could still be in use.
Address this by using kfree_rcu to free the memory for the mpls device
after the RCU grace period has elapsed.
Fixes: 03c57747a7 ("mpls: Per-device MPLS state")
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we scan a packet for GRO processing, we want to see the most
common packet types in the front of the offload_base list.
So add a priority field so we can handle this properly.
IPv4/IPv6 get the highest priority with the implicit zero priority
field.
Next comes ethernet with a priority of 10, and then we have the MPLS
types with a priority of 15.
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Suggested-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since these are now visible to userspace it is nice to be consistent
with BSD (sys/netmpls/mpls.h in netBSD).
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move to include/uapi/linux/mpls.h to be externally visibile.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The reserved implicit-NULL label isn't allowed to appear in the label
stack for packets, so make it an error for the control plane to
specify it as an outgoing label.
Suggested-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Robert Shearman
Roopa Prabhu
Eric W. Biederman
Nikolay Aleksandrov
Tom Herbert
Jiri Benc
Dan Carpenter
David S. Miller