[PATCH net-next 0/2] net/ipv6: Handle onlink flag with multipath routes

[PATCH net-next 0/2] net/ipv6: Handle onlink flag with multipath routes

[David Ahern]

ONLINK flag is per nexthop. For multipath routes it is specified in rtnh_flags
in struct rtnexthop versus rtm_flags for single path routes. Update
ip6_route_multipath_add to look at rtnh_flags before the call to
ip6_route_info_create.

Add multipath test cases as well.

David Ahern (2):
  net/ipv6: Handle onlink flag with multipath routes
  selftests: Add multipath tests for onlink flag

 net/ipv6/route.c                                |  1 +
 tools/testing/selftests/net/fib-onlink-tests.sh | 92 ++++++++++++++++++++++++-
 2 files changed, 90 insertions(+), 3 deletions(-)

-- 
2.11.0

[PATCH net-next 1/2] net/ipv6: Handle onlink flag with multipath routes

[David Ahern]

For multipath routes the ONLINK flag is specified per nexthop in rtnh_flags
(as opposed to rtm_flags for unicast routes). Update ip6_route_multipath_add
to set fc_flags based on rtnh_flags.

Fixes: fc1e64e1092f ("net/ipv6: Add support for onlink flag")
Signed-off-by: David Ahern <dsahern@gmail.com>
---
 net/ipv6/route.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index f0ae58424c45..b223dffa8521 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -4166,6 +4166,7 @@ static int ip6_route_multipath_add(struct fib6_config *cfg,
 				r_cfg.fc_encap_type = nla_get_u16(nla);
 		}
 
+		r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
 		rt = ip6_route_info_create(&r_cfg, extack);
 		if (IS_ERR(rt)) {
 			err = PTR_ERR(rt);
-- 
2.11.0

[PATCH net-next 2/2] selftests: Add multipath tests for onlink flag

[David Ahern]

Add multipath tests for onlink flag: one test with onlink added to
both nexthops, then tests with onlink added to only 1 nexthop.

Signed-off-by: David Ahern <dsahern@gmail.com>
---
 tools/testing/selftests/net/fib-onlink-tests.sh | 92 ++++++++++++++++++++++++-
 1 file changed, 89 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/net/fib-onlink-tests.sh b/tools/testing/selftests/net/fib-onlink-tests.sh
index 06b1d7cc12cc..fcf0b589e652 100755
--- a/tools/testing/selftests/net/fib-onlink-tests.sh
+++ b/tools/testing/selftests/net/fib-onlink-tests.sh
@@ -56,7 +56,8 @@ TEST_NET6[2]=2001:db8:102
 
 # connected gateway
 CONGW[1]=169.254.1.254
-CONGW[2]=169.254.5.254
+CONGW[2]=169.254.3.254
+CONGW[3]=169.254.5.254
 
 # recursive gateway
 RECGW4[1]=169.254.11.254
@@ -232,6 +233,23 @@ run_ip()
 	log_test $? ${exp_rc} "${desc}"
 }
 
+run_ip_mpath()
+{
+	local table="$1"
+	local prefix="$2"
+	local nh1="$3"
+	local nh2="$4"
+	local exp_rc="$5"
+	local desc="$6"
+
+	# dev arg may be empty
+	[ -n "${dev}" ] && dev="dev ${dev}"
+
+	run_cmd ip ro add table "${table}" "${prefix}"/32 \
+		nexthop via ${nh1} nexthop via ${nh2}
+	log_test $? ${exp_rc} "${desc}"
+}
+
 valid_onlink_ipv4()
 {
 	# - unicast connected, unicast recursive
@@ -243,13 +261,37 @@ valid_onlink_ipv4()
 
 	log_subsection "VRF ${VRF}"
 
-	run_ip ${VRF_TABLE} ${TEST_NET4[2]}.1 ${CONGW[2]} ${NETIFS[p5]} 0 "unicast connected"
+	run_ip ${VRF_TABLE} ${TEST_NET4[2]}.1 ${CONGW[3]} ${NETIFS[p5]} 0 "unicast connected"
 	run_ip ${VRF_TABLE} ${TEST_NET4[2]}.2 ${RECGW4[2]} ${NETIFS[p5]} 0 "unicast recursive"
 
 	log_subsection "VRF device, PBR table"
 
-	run_ip ${PBR_TABLE} ${TEST_NET4[2]}.3 ${CONGW[2]} ${NETIFS[p5]} 0 "unicast connected"
+	run_ip ${PBR_TABLE} ${TEST_NET4[2]}.3 ${CONGW[3]} ${NETIFS[p5]} 0 "unicast connected"
 	run_ip ${PBR_TABLE} ${TEST_NET4[2]}.4 ${RECGW4[2]} ${NETIFS[p5]} 0 "unicast recursive"
+
+	# multipath version
+	#
+	log_subsection "default VRF - main table - multipath"
+
+	run_ip_mpath 254 ${TEST_NET4[1]}.5 \
+		"${CONGW[1]} dev ${NETIFS[p1]} onlink" \
+		"${CONGW[2]} dev ${NETIFS[p3]} onlink" \
+		0 "unicast connected - multipath"
+
+	run_ip_mpath 254 ${TEST_NET4[1]}.6 \
+		"${RECGW4[1]} dev ${NETIFS[p1]} onlink" \
+		"${RECGW4[2]} dev ${NETIFS[p3]} onlink" \
+		0 "unicast recursive - multipath"
+
+	run_ip_mpath 254 ${TEST_NET4[1]}.7 \
+		"${CONGW[1]} dev ${NETIFS[p1]}"        \
+		"${CONGW[2]} dev ${NETIFS[p3]} onlink" \
+		0 "unicast connected - multipath onlink first only"
+
+	run_ip_mpath 254 ${TEST_NET4[1]}.8 \
+		"${CONGW[1]} dev ${NETIFS[p1]} onlink" \
+		"${CONGW[2]} dev ${NETIFS[p3]}"        \
+		0 "unicast connected - multipath onlink second only"
 }
 
 invalid_onlink_ipv4()
@@ -289,6 +331,20 @@ run_ip6()
 	log_test $? ${exp_rc} "${desc}"
 }
 
+run_ip6_mpath()
+{
+	local table="$1"
+	local prefix="$2"
+	local nh1="$3"
+	local nh2="$4"
+	local exp_rc="$5"
+	local desc="$6"
+
+	run_cmd ip -6 ro add table "${table}" "${prefix}"/128 \
+		nexthop via ${nh1} nexthop via ${nh2}
+	log_test $? ${exp_rc} "${desc}"
+}
+
 valid_onlink_ipv6()
 {
 	# - unicast connected, unicast recursive, v4-mapped
@@ -310,6 +366,35 @@ valid_onlink_ipv6()
 	run_ip6 ${PBR_TABLE} ${TEST_NET6[2]}::4 ${V6ADDRS[p5]/::*}::64 ${NETIFS[p5]} 0 "unicast connected"
 	run_ip6 ${PBR_TABLE} ${TEST_NET6[2]}::5 ${RECGW6[2]} ${NETIFS[p5]} 0 "unicast recursive"
 	run_ip6 ${PBR_TABLE} ${TEST_NET6[2]}::6 ::ffff:${TEST_NET4IN6[2]} ${NETIFS[p5]} 0 "v4-mapped"
+
+	# multipath version
+	#
+	log_subsection "default VRF - main table - multipath"
+
+	run_ip6_mpath 254 ${TEST_NET6[1]}::4 \
+		"${V6ADDRS[p1]/::*}::64 dev ${NETIFS[p1]} onlink" \
+		"${V6ADDRS[p3]/::*}::64 dev ${NETIFS[p3]} onlink" \
+		0 "unicast connected - multipath onlink"
+
+	run_ip6_mpath 254 ${TEST_NET6[1]}::5 \
+		"${RECGW6[1]} dev ${NETIFS[p1]} onlink" \
+		"${RECGW6[2]} dev ${NETIFS[p3]} onlink" \
+		0 "unicast recursive - multipath onlink"
+
+	run_ip6_mpath 254 ${TEST_NET6[1]}::6 \
+		"::ffff:${TEST_NET4IN6[1]} dev ${NETIFS[p1]} onlink" \
+		"::ffff:${TEST_NET4IN6[2]} dev ${NETIFS[p3]} onlink" \
+		0 "v4-mapped - multipath onlink"
+
+	run_ip6_mpath 254 ${TEST_NET6[1]}::7 \
+		"${V6ADDRS[p1]/::*}::64 dev ${NETIFS[p1]} onlink" \
+		"${V6ADDRS[p3]/::*}::64 dev ${NETIFS[p3]}" \
+		0 "unicast connected - multipath onlink first only"
+
+	run_ip6_mpath 254 ${TEST_NET6[1]}::8 \
+		"${V6ADDRS[p1]/::*}::64 dev ${NETIFS[p1]}"        \
+		"${V6ADDRS[p3]/::*}::64 dev ${NETIFS[p3]} onlink" \
+		0 "unicast connected - multipath onlink second only"
 }
 
 invalid_onlink_ipv6()
@@ -355,6 +440,7 @@ run_onlink_tests()
 	log_section "IPv6 onlink"
 	log_subsection "Valid onlink commands"
 	valid_onlink_ipv6
+	log_subsection "Invalid onlink commands"
 	invalid_onlink_ipv6
 }
 
-- 
2.11.0

Re: [PATCH net-next 1/2] net/ipv6: Handle onlink flag with multipath routes

[David Miller]

From: David Ahern <dsahern@gmail.com>
Date: Tue, 13 Mar 2018 08:40:09 -0700

> For multipath routes the ONLINK flag is specified per nexthop in rtnh_flags
> (as opposed to rtm_flags for unicast routes). Update ip6_route_multipath_add
> to set fc_flags based on rtnh_flags.
> 
> Fixes: fc1e64e1092f ("net/ipv6: Add support for onlink flag")
> Signed-off-by: David Ahern <dsahern@gmail.com>
> ---
>  net/ipv6/route.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/net/ipv6/route.c b/net/ipv6/route.c
> index f0ae58424c45..b223dffa8521 100644
> --- a/net/ipv6/route.c
> +++ b/net/ipv6/route.c
> @@ -4166,6 +4166,7 @@ static int ip6_route_multipath_add(struct fib6_config *cfg,
>  				r_cfg.fc_encap_type = nla_get_u16(nla);
>  		}
>  
> +		r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
>  		rt = ip6_route_info_create(&r_cfg, extack);
>  		if (IS_ERR(rt)) {
>  			err = PTR_ERR(rt);

Hmmm, this actually "accumulates" the flag rather than sets it.

Have you thought about what should happen if the cfg has RTNH_F_ONLINK
set?

I think you should either change this logic to a true 'set', or adjust
your commit message to address this aspect of the new behavior.

Thank you.

Re: [PATCH net-next 1/2] net/ipv6: Handle onlink flag with multipath routes

[David Ahern]

On 3/16/18 8:40 AM, David Miller wrote:
> From: David Ahern <dsahern@gmail.com>
> Date: Tue, 13 Mar 2018 08:40:09 -0700
> 
>> For multipath routes the ONLINK flag is specified per nexthop in rtnh_flags
>> (as opposed to rtm_flags for unicast routes). Update ip6_route_multipath_add
>> to set fc_flags based on rtnh_flags.
>>
>> Fixes: fc1e64e1092f ("net/ipv6: Add support for onlink flag")
>> Signed-off-by: David Ahern <dsahern@gmail.com>
>> ---
>>  net/ipv6/route.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/net/ipv6/route.c b/net/ipv6/route.c
>> index f0ae58424c45..b223dffa8521 100644
>> --- a/net/ipv6/route.c
>> +++ b/net/ipv6/route.c
>> @@ -4166,6 +4166,7 @@ static int ip6_route_multipath_add(struct fib6_config *cfg,
>>  				r_cfg.fc_encap_type = nla_get_u16(nla);
>>  		}
>>  
>> +		r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
>>  		rt = ip6_route_info_create(&r_cfg, extack);
>>  		if (IS_ERR(rt)) {
>>  			err = PTR_ERR(rt);
> 
> Hmmm, this actually "accumulates" the flag rather than sets it.
> 
> Have you thought about what should happen if the cfg has RTNH_F_ONLINK
> set?

yes, that's why the test script adds cases with the ONLINK flag set for
both nexthops, then one with it on the first nexthop only, and one with
the flag only on the second nexthop.

If you look at the full loop 'cfg' is the variable with the user data,
and r_cfg is the 'local loop version' so r_cfg.fc_flags gets reset for
each nexthop:

        while (rtnh_ok(rtnh, remaining)) {
                memcpy(&r_cfg, cfg, sizeof(*cfg));
		...
		r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
		rt = ip6_route_info_create(&r_cfg, extack);


> 
> I think you should either change this logic to a true 'set', or adjust
> your commit message to address this aspect of the new behavior.

I can update the commit message.

Re: [PATCH net-next 1/2] net/ipv6: Handle onlink flag with multipath routes

[David Miller]

From: David Ahern <dsahern@gmail.com>
Date: Fri, 16 Mar 2018 08:45:10 -0700

> On 3/16/18 8:40 AM, David Miller wrote:
>> Hmmm, this actually "accumulates" the flag rather than sets it.
>> 
>> Have you thought about what should happen if the cfg has RTNH_F_ONLINK
>> set?
> 
> yes, that's why the test script adds cases with the ONLINK flag set for
> both nexthops, then one with it on the first nexthop only, and one with
> the flag only on the second nexthop.
> 
> If you look at the full loop 'cfg' is the variable with the user data,
> and r_cfg is the 'local loop version' so r_cfg.fc_flags gets reset for
> each nexthop:
> 
>         while (rtnh_ok(rtnh, remaining)) {
>                 memcpy(&r_cfg, cfg, sizeof(*cfg));
> 		...
> 		r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
> 		rt = ip6_route_info_create(&r_cfg, extack);

Right.

>> I think you should either change this logic to a true 'set', or adjust
>> your commit message to address this aspect of the new behavior.
> 
> I can update the commit message.

Please do, thanks David.

Re: [PATCH net-next 1/2] net/ipv6: Handle onlink flag with multipath routes

[David Ahern]

On 3/16/18 9:38 AM, David Miller wrote:
> From: David Ahern <dsahern@gmail.com>
> Date: Fri, 16 Mar 2018 08:45:10 -0700
> 
>> On 3/16/18 8:40 AM, David Miller wrote:
>>> Hmmm, this actually "accumulates" the flag rather than sets it.
>>>
>>> Have you thought about what should happen if the cfg has RTNH_F_ONLINK
>>> set?
>>
>> yes, that's why the test script adds cases with the ONLINK flag set for
>> both nexthops, then one with it on the first nexthop only, and one with
>> the flag only on the second nexthop.
>>
>> If you look at the full loop 'cfg' is the variable with the user data,
>> and r_cfg is the 'local loop version' so r_cfg.fc_flags gets reset for
>> each nexthop:
>>
>>         while (rtnh_ok(rtnh, remaining)) {
>>                 memcpy(&r_cfg, cfg, sizeof(*cfg));
>> 		...
>> 		r_cfg.fc_flags |= (rtnh->rtnh_flags & RTNH_F_ONLINK);
>> 		rt = ip6_route_info_create(&r_cfg, extack);
> 
> Right.
> 
>>> I think you should either change this logic to a true 'set', or adjust
>>> your commit message to address this aspect of the new behavior.
>>
>> I can update the commit message.
> 
> Please do, thanks David.
> 

And it looks like patch 1 needs to be in 'net'; did not realize the ipv6
ONLINK support is already in 4.16. I will send the patch adding tests
separately for net-next.