linux-stable.git/net/mpls, branch linux-5.0.y

mpls: Return error for RTA_GATEWAY attribute

2019-02-26T21:23:17+00:00

MPLS does not support nexthops with an MPLS address family.
Specifically, it does not handle RTA_GATEWAY attribute. Make it
clear by returning an error.

Fixes: 03c0566542f4c ("mpls: Netlink commands to add, remove, and dump routes")
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net/mpls: Handle kernel side filtering of route dumps

2018-10-16T07:14:07+00:00

Update the dump request parsing in MPLS for the non-INET case to
enable kernel side filtering. If INET is disabled the only filters
that make sense for MPLS are protocol and nexthop device.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: Enable kernel side filtering of route dumps

2018-10-16T07:14:07+00:00

Update parsing of route dump request to enable kernel side filtering.
Allow filtering results by protocol (e.g., which routing daemon installed
the route), route type (e.g., unicast), table id and nexthop device. These
amount to the low hanging fruit, yet a huge improvement, for dumping
routes.

ip_valid_fib_dump_req is called with RTNL held, so __dev_get_by_index can
be used to look up the device index without taking a reference. From
there filter->dev is only used during dump loops with the lock still held.

Set NLM_F_DUMP_FILTERED in the answer_flags so the user knows the results
have been filtered should no entries be returned.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net/mpls: Plumb support for filtering route dumps

2018-10-16T07:13:12+00:00

Implement kernel side filtering of routes by egress device index and
protocol. MPLS uses only a single table and route type.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: Add struct for fib dump filter

2018-10-16T07:13:12+00:00

Add struct fib_dump_filter for options on limiting which routes are
returned in a dump request. The current list is table id, protocol,
route type, rtm_flags and nexthop device index. struct net is needed
to lookup the net_device from the index.

Declare the filter for each route dump handler and plumb the new
arguments from dump handlers to ip_valid_fib_dump_req.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net/mpls: Implement handler for strict data checking on dumps

2018-10-11T05:46:17+00:00

Without CONFIG_INET enabled compiles fail with:

net/mpls/af_mpls.o: In function `mpls_dump_routes':
af_mpls.c:(.text+0xed0): undefined reference to `ip_valid_fib_dump_req'

The preference is for MPLS to use the same handler as ipv4 and ipv6
to allow consistency when doing a dump for AF_UNSPEC which walks
all address families invoking the route dump handler. If INET is
disabled then fallback to an MPLS version which can be tighter on
the data checks.

Fixes: e8ba330ac0c5 ("rtnetlink: Update fib dumps for strict data checking")
Reported-by: Randy Dunlap 
Reported-by: Arnd Bergmann 
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: Update netconf dump handlers for strict data checking

2018-10-08T17:39:05+00:00

Update inet_netconf_dump_devconf, inet6_netconf_dump_devconf, and
mpls_netconf_dump_devconf for strict data checking. If the flag is set,
the dump request is expected to have an netconfmsg struct as the header.
The struct only has the family member and no attributes can be appended.

Signed-off-by: David Ahern 
Acked-by: Christian Brauner 
Signed-off-by: David S. Miller

rtnetlink: Update fib dumps for strict data checking

2018-10-08T17:39:05+00:00

Add helper to check netlink message for route dumps. If the strict flag
is set the dump request is expected to have an rtmsg struct as the header.
All elements of the struct are expected to be 0 with the exception of
rtm_flags (which is used by both ipv4 and ipv6 dumps) and no attributes
can be appended. rtm_flags can only have RTM_F_CLONED and RTM_F_PREFIX
set.

Update inet_dump_fib, inet6_dump_fib, mpls_dump_routes, ipmr_rtm_dumproute,
and ip6mr_rtm_dumproute to call this helper if strict data checking is
enabled.

Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

net: Add extack to nlmsg_parse

2018-10-08T17:39:04+00:00

Make sure extack is passed to nlmsg_parse where easy to do so.
Most of these are dump handlers and leveraging the extack in
the netlink_callback.

Signed-off-by: David Ahern 
Acked-by: Christian Brauner 
Signed-off-by: David S. Miller

mpls: allow routes on ip6gre devices

2018-09-24T19:19:27+00:00

Summary:

This appears to be necessary and sufficient change to enable `MPLS` on
`ip6gre` tunnels (RFC4023).

This diff allows IP6GRE devices to be recognized by MPLS kernel module
and hence user can configure interface to accept packets with mpls
headers as well setup mpls routes on them.

Test Plan:

Test plan consists of multiple containers connected via GRE-V6 tunnel.
Then carrying out testing steps as below.

- Carry out necessary sysctl settings on all containers

```
sysctl -w net.mpls.platform_labels=65536
sysctl -w net.mpls.ip_ttl_propagate=1
sysctl -w net.mpls.conf.lo.input=1
```

- Establish IP6GRE tunnels

```
ip -6 tunnel add name if_1_2_1 mode ip6gre \
  local 2401:db00:21:6048:feed:0::1 \
  remote 2401:db00:21:6048:feed:0::2 key 1
ip link set dev if_1_2_1 up
sysctl -w net.mpls.conf.if_1_2_1.input=1
ip -4 addr add 169.254.0.2/31 dev if_1_2_1 scope link

ip -6 tunnel add name if_1_3_1 mode ip6gre \
  local 2401:db00:21:6048:feed:0::1 \
  remote 2401:db00:21:6048:feed:0::3 key 1
ip link set dev if_1_3_1 up
sysctl -w net.mpls.conf.if_1_3_1.input=1
ip -4 addr add 169.254.0.4/31 dev if_1_3_1 scope link
```

- Install MPLS encap rules on node-1 towards node-2

```
ip route add 192.168.0.11/32 nexthop encap mpls 32/64 \
  via inet 169.254.0.3 dev if_1_2_1
```

- Install MPLS forwarding rules on node-2 and node-3
```
// node2
ip -f mpls route add 32 via inet 169.254.0.7 dev if_2_4_1

// node3
ip -f mpls route add 64 via inet 169.254.0.12 dev if_4_3_1
```

- Ping 192.168.0.11 (node4) from 192.168.0.1 (node1) (where routing
  towards 192.168.0.1 is via IP route directly towards node1 from node4)
```
ping 192.168.0.11
```

- tcpdump on interface to capture ping packets wrapped within MPLS
  header which inturn wrapped within IP6GRE header

```
16:43:41.121073 IP6
  2401:db00:21:6048:feed::1 > 2401:db00:21:6048:feed::2:
  DSTOPT GREv0, key=0x1, length 100:
  MPLS (label 32, exp 0, ttl 255) (label 64, exp 0, [S], ttl 255)
  IP 192.168.0.1 > 192.168.0.11:
  ICMP echo request, id 1208, seq 45, length 64

0x0000:  6000 2cdb 006c 3c3f 2401 db00 0021 6048  `.,..l
Signed-off-by: David S. Miller