From: Geliang Tang <tanggeliang@kylinos.cn>

This patch adds a subtest named test_subflow to load and verify the newly
added mptcp subflow example in test_mptcp. Add a helper endpoint_init()
to add a new subflow endpoint. Add another helper ss_search() to verify the
fwmark and congestion values set by mptcp_subflow prog using setsockopts.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/76
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 tools/testing/selftests/bpf/prog_tests/mptcp.c | 109 +++++++++++++++++++++++++
 1 file changed, 109 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
index 274d2e033e39..6039b0ff3801 100644
--- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
@@ -9,8 +9,12 @@
 #include "network_helpers.h"
 #include "mptcp_sock.skel.h"
 #include "mptcpify.skel.h"
+#include "mptcp_subflow.skel.h"
 
 #define NS_TEST "mptcp_ns"
+#define ADDR_1	"10.0.1.1"
+#define ADDR_2	"10.0.1.2"
+#define PORT_1	10001
 
 #ifndef IPPROTO_MPTCP
 #define IPPROTO_MPTCP 262
@@ -340,10 +344,115 @@ static void test_mptcpify(void)
 	close(cgroup_fd);
 }
 
+static int endpoint_init(char *flags)
+{
+	SYS(fail, "ip -net %s link add veth1 type veth peer name veth2", NS_TEST);
+	SYS(fail, "ip -net %s addr add %s/24 dev veth1", NS_TEST, ADDR_1);
+	SYS(fail, "ip -net %s link set dev veth1 up", NS_TEST);
+	SYS(fail, "ip -net %s addr add %s/24 dev veth2", NS_TEST, ADDR_2);
+	SYS(fail, "ip -net %s link set dev veth2 up", NS_TEST);
+	SYS(fail, "ip -net %s mptcp endpoint add %s %s", NS_TEST, ADDR_2, flags);
+
+	return 0;
+fail:
+	return -1;
+}
+
+static int _ss_search(char *src, char *dst, char *port, char *keyword)
+{
+	char cmd[128];
+	int n;
+
+	n = snprintf(cmd, sizeof(cmd),
+		     "ip netns exec %s ss -Menita src %s dst %s %s %d | grep -q '%s'",
+		     NS_TEST, src, dst, port, PORT_1, keyword);
+	if (n < 0 || n >= sizeof(cmd))
+		return -1;
+
+	return system(cmd);
+}
+
+static int ss_search(char *src, char *keyword)
+{
+	return _ss_search(src, ADDR_1, "dport", keyword);
+}
+
+static void run_subflow(char *new)
+{
+	int server_fd, client_fd, err;
+	char cc[TCP_CA_NAME_MAX];
+	socklen_t len = sizeof(cc);
+
+	server_fd = start_mptcp_server(AF_INET, ADDR_1, PORT_1, 0);
+	if (!ASSERT_GE(server_fd, 0, "start_mptcp_server"))
+		return;
+
+	client_fd = connect_to_fd(server_fd, 0);
+	if (!ASSERT_GE(client_fd, 0, "connect to fd"))
+		goto fail;
+
+	err = getsockopt(server_fd, SOL_TCP, TCP_CONGESTION, cc, &len);
+	if (!ASSERT_OK(err, "getsockopt(srv_fd, TCP_CONGESTION)"))
+		goto fail;
+
+	send_byte(client_fd);
+
+	ASSERT_OK(ss_search(ADDR_1, "fwmark:0x1"), "ss_search fwmark:0x1");
+	ASSERT_OK(ss_search(ADDR_2, "fwmark:0x2"), "ss_search fwmark:0x2");
+	ASSERT_OK(ss_search(ADDR_1, new), "ss_search new cc");
+	ASSERT_OK(ss_search(ADDR_2, cc), "ss_search default cc");
+
+	close(client_fd);
+fail:
+	close(server_fd);
+}
+
+static void test_subflow(void)
+{
+	int cgroup_fd, prog_fd, err;
+	struct mptcp_subflow *skel;
+	struct nstoken *nstoken;
+
+	cgroup_fd = test__join_cgroup("/mptcp_subflow");
+	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup: mptcp_subflow"))
+		return;
+
+	skel = mptcp_subflow__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "skel_open_load: mptcp_subflow"))
+		goto close_cgroup;
+
+	err = mptcp_subflow__attach(skel);
+	if (!ASSERT_OK(err, "skel_attach: mptcp_subflow"))
+		goto skel_destroy;
+
+	prog_fd = bpf_program__fd(skel->progs.mptcp_subflow);
+	err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0);
+	if (!ASSERT_OK(err, "prog_attach"))
+		goto skel_destroy;
+
+	nstoken = create_netns();
+	if (!ASSERT_OK_PTR(nstoken, "create_netns: mptcp_subflow"))
+		goto skel_destroy;
+
+	if (!ASSERT_OK(endpoint_init("subflow"), "endpoint_init"))
+		goto close_netns;
+
+	run_subflow(skel->data->cc);
+
+close_netns:
+	cleanup_netns(nstoken);
+skel_destroy:
+	mptcp_subflow__destroy(skel);
+close_cgroup:
+	close(cgroup_fd);
+}
+
 void test_mptcp(void)
 {
 	if (test__start_subtest("base"))
 		test_base();
 	if (test__start_subtest("mptcpify"))
 		test_mptcpify();
+	if (test__start_subtest("subflow"))
+		test_subflow();
 }

-- 
2.43.0

Hello,

On 09/05/2024 17:49, Matthieu Baerts (NGI0) wrote:
> From: Geliang Tang <tanggeliang@kylinos.cn>
> 
> This patch adds a subtest named test_subflow to load and verify the newly
> added mptcp subflow example in test_mptcp. Add a helper endpoint_init()
> to add a new subflow endpoint. Add another helper ss_search() to verify the
> fwmark and congestion values set by mptcp_subflow prog using setsockopts.
> 
> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/76
> Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
> Reviewed-by: Mat Martineau <martineau@kernel.org>
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> ---
>  tools/testing/selftests/bpf/prog_tests/mptcp.c | 109 +++++++++++++++++++++++++
>  1 file changed, 109 insertions(+)
> 
> diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
> index 274d2e033e39..6039b0ff3801 100644
> --- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
> +++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c

(...)

> @@ -340,10 +344,115 @@ static void test_mptcpify(void)
>  	close(cgroup_fd);
>  }
>  
> +static int endpoint_init(char *flags)
> +{
> +	SYS(fail, "ip -net %s link add veth1 type veth peer name veth2", NS_TEST);
> +	SYS(fail, "ip -net %s addr add %s/24 dev veth1", NS_TEST, ADDR_1);
> +	SYS(fail, "ip -net %s link set dev veth1 up", NS_TEST);
> +	SYS(fail, "ip -net %s addr add %s/24 dev veth2", NS_TEST, ADDR_2);
> +	SYS(fail, "ip -net %s link set dev veth2 up", NS_TEST);
> +	SYS(fail, "ip -net %s mptcp endpoint add %s %s", NS_TEST, ADDR_2, flags);

I just noticed that this command is failing on the BPF CI:

  https://github.com/kernel-patches/bpf/actions/runs/9020020315?pr=7009

Is it possible that an old version of IPRoute2 is installed?
'ip mptcp' is supported since v5.8.0 (from 2020).

It looks like Ubuntu Focal 20.04 is being used, which has the v5.5.0. Do
we then need to find another way to set the MPTCP endpoints?

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.

On Thu, May 9, 2024 at 11:31 AM Matthieu Baerts <matttbe@kernel.org> wrote:
>
> Hello,
>
> On 09/05/2024 17:49, Matthieu Baerts (NGI0) wrote:
> > From: Geliang Tang <tanggeliang@kylinos.cn>
> >
> > This patch adds a subtest named test_subflow to load and verify the newly
> > added mptcp subflow example in test_mptcp. Add a helper endpoint_init()
> > to add a new subflow endpoint. Add another helper ss_search() to verify the
> > fwmark and congestion values set by mptcp_subflow prog using setsockopts.
> >
> > Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/76
> > Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
> > Reviewed-by: Mat Martineau <martineau@kernel.org>
> > Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> > ---
> >  tools/testing/selftests/bpf/prog_tests/mptcp.c | 109 +++++++++++++++++++++++++
> >  1 file changed, 109 insertions(+)
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
> > index 274d2e033e39..6039b0ff3801 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
>
> (...)
>
> > @@ -340,10 +344,115 @@ static void test_mptcpify(void)
> >       close(cgroup_fd);
> >  }
> >
> > +static int endpoint_init(char *flags)
> > +{
> > +     SYS(fail, "ip -net %s link add veth1 type veth peer name veth2", NS_TEST);
> > +     SYS(fail, "ip -net %s addr add %s/24 dev veth1", NS_TEST, ADDR_1);
> > +     SYS(fail, "ip -net %s link set dev veth1 up", NS_TEST);
> > +     SYS(fail, "ip -net %s addr add %s/24 dev veth2", NS_TEST, ADDR_2);
> > +     SYS(fail, "ip -net %s link set dev veth2 up", NS_TEST);
> > +     SYS(fail, "ip -net %s mptcp endpoint add %s %s", NS_TEST, ADDR_2, flags);
>
> I just noticed that this command is failing on the BPF CI:
>
>   https://github.com/kernel-patches/bpf/actions/runs/9020020315?pr=7009
>
> Is it possible that an old version of IPRoute2 is installed?
> 'ip mptcp' is supported since v5.8.0 (from 2020).
>
> It looks like Ubuntu Focal 20.04 is being used, which has the v5.5.0. Do
> we then need to find another way to set the MPTCP endpoints?


Manu, any idea?