selftests/net: convert fib_rule_tests.sh to run it in unique namespace

Here is the test result after conversion.

]# ./fib_rule_tests.sh

TEST: rule6 check: oif redirect to table [ OK ]

...

TEST: rule4 dsfield tcp connect (dsfield 0x07) [ OK ]

Tests passed: 66
Tests failed: 0

Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20231213060856.4030084-12-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: fib_rule_tests: Test UDP and TCP connections with DSCP rules.

Add the fib_rule6_send and fib_rule4_send tests to verify that DSCP
values are properly taken into account when UDP or TCP sockets try to
connect().

Tests are done with nettest, which needs a new option to specify
the DS Field value of the socket being tested. This new option is
named '-Q', in reference to the similar option used by ping.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: net: fib_rule_tests: fix support for running individual tests

parsing and usage of -t got missed in the previous patch.
this patch fixes it

Fixes: 816cda9ae531 ("selftests: net: fib_rule_tests: add support to select a test to run")
Signed-off-by: Alaa Mohamed <eng.alaamohamedsoliman.am@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: fib_rule_tests: add support to select a test to run

Add boilerplate test loop in test to run all tests
in fib_rule_tests.sh

Signed-off-by: Alaa Mohamed <eng.alaamohamedsoliman.am@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipv4: Stop taking ECN bits into account in fib4-rules

Use the new dscp_t type to replace the tos field of struct fib4_rule,
so that fib4-rules consistently ignore ECN bits.

Before this patch, fib4-rules did accept rules with the high order ECN
bit set (but not the low order one). Also, it relied on its callers
masking the ECN bits of ->flowi4_tos to prevent those from influencing
the result. This was brittle and a few call paths still do the lookup
without masking the ECN bits first.

After this patch fib4-rules only compare the DSCP bits. ECN can't
influence the result anymore, even if the caller didn't mask these
bits. Also, fib4-rules now must have both ECN bits cleared or they will
be rejected.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ipv6: Define dscp_t and stop taking ECN bits into account in fib6-rules

Define a dscp_t type and its appropriate helpers that ensure ECN bits
are not taken into account when handling DSCP.

Use this new type to replace the tclass field of struct fib6_rule, so
that fib6-rules don't get influenced by ECN bits anymore.

Before this patch, fib6-rules didn't make any distinction between the
DSCP and ECN bits. Therefore, rules specifying a DSCP (tos or dsfield
options in iproute2) stopped working as soon a packets had at least one
of its ECN bits set (as a work around one could create four rules for
each DSCP value to match, one for each possible ECN value).

After this patch fib6-rules only compare the DSCP bits. ECN doesn't
influence the result anymore. Also, fib6-rules now must have the ECN
bits cleared or they will be rejected.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Acked-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: fib rule: Don't echo modified sysctls

Run sysctl in quiet mode. Echoing the modified sysctl doesn't bring any
useful information.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib rule: Log test description

All callers of fib_rule6_test_match_n_redirect() and
fib_rule4_test_match_n_redirect() pass a third argument containing a
description of the test being run. Instead of ignoring this argument,
let's use it for logging instead of printing a truncated version of the
command.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib rule: Drop erroneous TABLE variable

The fib_rule6_del_by_pref() and fib_rule4_del_by_pref() functions use
an uninitialised $TABLE variable. They should use $RTABLE instead.
This doesn't alter the result of the test, as it just makes the grep
command less specific (but since the script always uses the same table
number, that doesn't really matter).

Let's fix it anyway and, while there, specify the filtering parameters
directly in 'ip -X rule show' to avoid the extra grep command entirely.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib rule: Make 'getmatch' and 'match' local variables

Let's restrict the scope of these variables to avoid possible
interferences.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests/net: Use kselftest skip code for skipped tests

There are several test cases in the net directory are still using
exit 0 or exit 1 when they need to be skipped. Use kselftest
framework skip code instead so it can help us to distinguish the
return status.

Criterion to filter out what should be fixed in net directory:
grep -r "exit [01]" -B1 | grep -i skip

This change might cause some false-positives if people are running
these test scripts directly and only checking their return codes,
which will change from 0 to 4. However I think the impact should be
small as most of our scripts here are already using this skip code.
And there will be no such issue if running them with the kselftest
framework.

Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/r/20210823085854.40216-1-po-hsu.lin@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: fib_rule_tests: use pre-defined DEV_ADDR

DEV_ADDR is defined but not used. Use it in address setting.
Do the same with IPv6 for consistency.

Reported-by: David Ahern <dsahern@gmail.com>
Fixes: fc82d93e57e3 ("selftests: fib_rule_tests: fix local IPv4 address typo")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib_rule_tests: enable forwarding before ipv4 from/iif test

As all the testing addresses are in the same subnet and egress device ==
ingress device. We need enable forwarding to get the route entry.

Also disable rp_filer separately as some distributions enable it in
startup scripts.

Fixes: 65b2b4939a64 ("selftests: net: initial fib rule tests")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib_rule_tests: fix local IPv4 address typo

The IPv4 testing address are all in 192.51.100.0 subnet. It doesn't make
sense to set a 198.51.100.1 local address. Should be a typo.

Fixes: 65b2b4939a64 ("selftests: net: initial fib rule tests")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib_rule_tests: print the result and return 1 if any tests failed

Fixes: 65b2b4939a64 ("selftests: net: initial fib rule tests")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: fib_rule_tests: Fix icmp proto with ipv6

A recent commit returns an error if icmp is used as the ip-proto for
IPv6 fib rules. Update fib_rule_tests to send ipv6-icmp instead of icmp.

Fixes: 5e1a99eae8499 ("ipv4: Add ICMPv6 support when parse route ipproto")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: initial fib rule tests

This adds a first set of tests for fib rule match/action for
ipv4 and ipv6. Initial tests only cover action lookup table.
can be extended to cover other actions in the future.
Uses ip route get to validate the rule lookup.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>