[PATCH mptcp-next v2 0/4] BPF 'force to MPTCP'

[PATCH mptcp-next v2 0/4] BPF 'force to MPTCP'

[Geliang Tang]

v2:
 - Address issue #79 "allow 'force to MPTCP' mode: BPF".
 - Define the prog in patch 3 in SEC "cgroup/sock_create" instead of
  "sockops".
 - Update other patches correspondingly.

v1:

This series depends on the two netns patches, should be inserted before
the BPF scheduler series:
  selftests/bpf: use random netns name for mptcp
  selftests/bpf: add two mptcp netns helpers
  bpf: Add bpf_mptcpify helper
  selftests/bpf: Test bpf_mptcpify helper
  selftests/bpf: Add mptcpify selftest
  mptcp: refactor push_pending logic

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/79

Geliang Tang (4):
  Squash to "selftests/bpf: add two mptcp netns helpers"
  bpf: Add bpf_mptcpify helper
  selftests/bpf: Test bpf_mptcpify helper
  selftests/bpf: Add mptcpify selftest

 include/linux/bpf.h                           |   1 +
 include/uapi/linux/bpf.h                      |   7 +
 kernel/bpf/cgroup.c                           |   2 +
 net/core/filter.c                             |  18 +++
 scripts/bpf_doc.py                            |   1 +
 tools/include/uapi/linux/bpf.h                |   7 +
 tools/testing/selftests/bpf/bpf_tcp_helpers.h |   1 +
 .../testing/selftests/bpf/prog_tests/mptcp.c  | 127 +++++++++++++++---
 tools/testing/selftests/bpf/progs/mptcpify.c  |  26 ++++
 9 files changed, 170 insertions(+), 20 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/progs/mptcpify.c

-- 
2.35.3

[PATCH mptcp-next v2 1/4] Squash to "selftests/bpf: add two mptcp netns helpers"

[Geliang Tang]

Move the helpers to the beginning.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/bpf/prog_tests/mptcp.c  | 40 +++++++++----------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
index a968641cc94a..e430bebebcf0 100644
--- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
@@ -26,6 +26,26 @@ struct mptcp_storage {
 	char ca_name[TCP_CA_NAME_MAX];
 };
 
+static struct nstoken *create_netns(void)
+{
+	srand(time(NULL));
+	snprintf(NS_TEST, sizeof(NS_TEST), "mptcp_ns_%d", rand());
+	SYS(fail, "ip netns add %s", NS_TEST);
+	SYS(fail, "ip -net %s link set dev lo up", NS_TEST);
+
+	return open_netns(NS_TEST);
+fail:
+	return NULL;
+}
+
+static void cleanup_netns(struct nstoken *nstoken)
+{
+	if (nstoken)
+		close_netns(nstoken);
+
+	SYS_NOFAIL("ip netns del %s &> /dev/null", NS_TEST);
+}
+
 static int verify_tsk(int map_fd, int client_fd)
 {
 	int err, cfd = client_fd;
@@ -142,26 +162,6 @@ static int run_test(int cgroup_fd, int server_fd, bool is_mptcp)
 	return err;
 }
 
-static struct nstoken *create_netns(void)
-{
-	srand(time(NULL));
-	snprintf(NS_TEST, sizeof(NS_TEST), "mptcp_ns_%d", rand());
-	SYS(fail, "ip netns add %s", NS_TEST);
-	SYS(fail, "ip -net %s link set dev lo up", NS_TEST);
-
-	return open_netns(NS_TEST);
-fail:
-	return NULL;
-}
-
-static void cleanup_netns(struct nstoken *nstoken)
-{
-	if (nstoken)
-		close_netns(nstoken);
-
-	SYS_NOFAIL("ip netns del %s &> /dev/null", NS_TEST);
-}
-
 static void test_base(void)
 {
 	struct nstoken *nstoken = NULL;
-- 
2.35.3

[PATCH mptcp-next v2 2/4] bpf: Add bpf_mptcpify helper

[Geliang Tang]

This patch implements a new struct bpf_func_proto bpf_mptcpify_proto. And
define a new helper bpf_mptcpify() to mptcpify a TCP socket dynamically as
an MPTCP one.

In bpf_mptcpify(), if the protocol ID of sk is IPPROTO_TCP, set it to
IPPROTO_MPTCP.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 include/linux/bpf.h            |  1 +
 include/uapi/linux/bpf.h       |  7 +++++++
 kernel/bpf/cgroup.c            |  2 ++
 net/core/filter.c              | 18 ++++++++++++++++++
 scripts/bpf_doc.py             |  1 +
 tools/include/uapi/linux/bpf.h |  7 +++++++
 6 files changed, 36 insertions(+)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index f58895830ada..424056fd5335 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2883,6 +2883,7 @@ extern const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto;
 extern const struct bpf_func_proto bpf_skc_to_udp6_sock_proto;
 extern const struct bpf_func_proto bpf_skc_to_unix_sock_proto;
 extern const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto;
+extern const struct bpf_func_proto bpf_mptcpify_proto;
 extern const struct bpf_func_proto bpf_copy_from_user_proto;
 extern const struct bpf_func_proto bpf_snprintf_btf_proto;
 extern const struct bpf_func_proto bpf_snprintf_proto;
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 60a9d59beeab..fa8a80024b67 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -5573,6 +5573,12 @@ union bpf_attr {
  *		0 on success.
  *
  *		**-ENOENT** if the bpf_local_storage cannot be found.
+ *
+ * struct sock *bpf_mptcpify(void *sk)
+ *	Description
+ *		Dynamically mptcpify a TCP socket *sk* pointer as an MPTCP one.
+ *	Return
+ *		*sk* if it's valid, or **NULL** otherwise.
  */
 #define ___BPF_FUNC_MAPPER(FN, ctx...)			\
 	FN(unspec, 0, ##ctx)				\
@@ -5787,6 +5793,7 @@ union bpf_attr {
 	FN(user_ringbuf_drain, 209, ##ctx)		\
 	FN(cgrp_storage_get, 210, ##ctx)		\
 	FN(cgrp_storage_delete, 211, ##ctx)		\
+	FN(mptcpify, 212, ##ctx)			\
 	/* */
 
 /* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index 5b2741aa0d9b..6b56de24e1a2 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -2542,6 +2542,8 @@ cgroup_common_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		default:
 			return &bpf_set_retval_proto;
 		}
+	case BPF_FUNC_mptcpify:
+		return &bpf_mptcpify_proto;
 	default:
 		return NULL;
 	}
diff --git a/net/core/filter.c b/net/core/filter.c
index 06ba0e56e369..e43b2c42c094 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -11678,6 +11678,24 @@ const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto = {
 	.ret_btf_id	= &btf_sock_ids[BTF_SOCK_TYPE_MPTCP],
 };
 
+BPF_CALL_1(bpf_mptcpify, struct sock *, sk)
+{
+	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP) {
+		sk->sk_protocol = IPPROTO_MPTCP;
+		return (unsigned long)sk;
+	}
+
+	return (unsigned long)NULL;
+}
+
+const struct bpf_func_proto bpf_mptcpify_proto = {
+	.func		= bpf_mptcpify,
+	.gpl_only	= false,
+	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
+	.ret_btf_id	= &btf_sock_ids[BTF_SOCK_TYPE_SOCK],
+	.arg1_type	= ARG_PTR_TO_CTX,
+};
+
 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
 {
 	return (unsigned long)sock_from_file(file);
diff --git a/scripts/bpf_doc.py b/scripts/bpf_doc.py
index eaae2ce78381..7a20ab9c6513 100755
--- a/scripts/bpf_doc.py
+++ b/scripts/bpf_doc.py
@@ -751,6 +751,7 @@ class PrinterHelpers(Printer):
             'struct file',
             'struct bpf_timer',
             'struct mptcp_sock',
+            'struct sock',
             'struct bpf_dynptr',
             'const struct bpf_dynptr',
             'struct iphdr',
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 60a9d59beeab..fa8a80024b67 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -5573,6 +5573,12 @@ union bpf_attr {
  *		0 on success.
  *
  *		**-ENOENT** if the bpf_local_storage cannot be found.
+ *
+ * struct sock *bpf_mptcpify(void *sk)
+ *	Description
+ *		Dynamically mptcpify a TCP socket *sk* pointer as an MPTCP one.
+ *	Return
+ *		*sk* if it's valid, or **NULL** otherwise.
  */
 #define ___BPF_FUNC_MAPPER(FN, ctx...)			\
 	FN(unspec, 0, ##ctx)				\
@@ -5787,6 +5793,7 @@ union bpf_attr {
 	FN(user_ringbuf_drain, 209, ##ctx)		\
 	FN(cgrp_storage_get, 210, ##ctx)		\
 	FN(cgrp_storage_delete, 211, ##ctx)		\
+	FN(mptcpify, 212, ##ctx)			\
 	/* */
 
 /* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't
-- 
2.35.3

Re: [PATCH mptcp-next v2 2/4] bpf: Add bpf_mptcpify helper

[kernel test robot]

Hi Geliang,

kernel test robot noticed the following build errors:

[auto build test ERROR on mptcp/export]
[also build test ERROR on mptcp/export-net linus/master v6.4 next-20230630]
[cannot apply to bpf-next/master bpf/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Geliang-Tang/Squash-to-selftests-bpf-add-two-mptcp-netns-helpers/20230701-205922
base:   https://github.com/multipath-tcp/mptcp_net-next.git export
patch link:    https://lore.kernel.org/r/daf3d1e26f19ee83b427ef9e17183cd09fc26de6.1688215769.git.geliang.tang%40suse.com
patch subject: [PATCH mptcp-next v2 2/4] bpf: Add bpf_mptcpify helper
config: x86_64-buildonly-randconfig-r001-20230701 (https://download.01.org/0day-ci/archive/20230701/202307012313.1sND4cvO-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230701/202307012313.1sND4cvO-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202307012313.1sND4cvO-lkp@intel.com/

All errors (new ones prefixed by >>):

   ld: kernel/bpf/cgroup.o: in function `cgroup_common_func_proto':
>> kernel/bpf/cgroup.c:2512: undefined reference to `bpf_mptcpify_proto'


vim +2512 kernel/bpf/cgroup.c

dea6a4e1701338 Stanislav Fomichev 2022-08-23  2507  
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2508  /* Common helpers for cgroup hooks. */
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2509  const struct bpf_func_proto *
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2510  cgroup_common_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2511  {
dea6a4e1701338 Stanislav Fomichev 2022-08-23 @2512  	switch (func_id) {
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2513  	case BPF_FUNC_get_local_storage:
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2514  		return &bpf_get_local_storage_proto;
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2515  	case BPF_FUNC_get_retval:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2516  		switch (prog->expected_attach_type) {
bed89185af0de0 Stanislav Fomichev 2022-08-23  2517  		case BPF_CGROUP_INET_INGRESS:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2518  		case BPF_CGROUP_INET_EGRESS:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2519  		case BPF_CGROUP_SOCK_OPS:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2520  		case BPF_CGROUP_UDP4_RECVMSG:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2521  		case BPF_CGROUP_UDP6_RECVMSG:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2522  		case BPF_CGROUP_INET4_GETPEERNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2523  		case BPF_CGROUP_INET6_GETPEERNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2524  		case BPF_CGROUP_INET4_GETSOCKNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2525  		case BPF_CGROUP_INET6_GETSOCKNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2526  			return NULL;
bed89185af0de0 Stanislav Fomichev 2022-08-23  2527  		default:
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2528  			return &bpf_get_retval_proto;
bed89185af0de0 Stanislav Fomichev 2022-08-23  2529  		}
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2530  	case BPF_FUNC_set_retval:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2531  		switch (prog->expected_attach_type) {
bed89185af0de0 Stanislav Fomichev 2022-08-23  2532  		case BPF_CGROUP_INET_INGRESS:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2533  		case BPF_CGROUP_INET_EGRESS:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2534  		case BPF_CGROUP_SOCK_OPS:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2535  		case BPF_CGROUP_UDP4_RECVMSG:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2536  		case BPF_CGROUP_UDP6_RECVMSG:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2537  		case BPF_CGROUP_INET4_GETPEERNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2538  		case BPF_CGROUP_INET6_GETPEERNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2539  		case BPF_CGROUP_INET4_GETSOCKNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2540  		case BPF_CGROUP_INET6_GETSOCKNAME:
bed89185af0de0 Stanislav Fomichev 2022-08-23  2541  			return NULL;
bed89185af0de0 Stanislav Fomichev 2022-08-23  2542  		default:
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2543  			return &bpf_set_retval_proto;
bed89185af0de0 Stanislav Fomichev 2022-08-23  2544  		}
96703c9170f3b5 Geliang Tang       2023-07-01  2545  	case BPF_FUNC_mptcpify:
96703c9170f3b5 Geliang Tang       2023-07-01  2546  		return &bpf_mptcpify_proto;
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2547  	default:
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2548  		return NULL;
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2549  	}
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2550  }
dea6a4e1701338 Stanislav Fomichev 2022-08-23  2551  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH mptcp-next v2 2/4] bpf: Add bpf_mptcpify helper

[kernel test robot]

Hi Geliang,

kernel test robot noticed the following build errors:

[auto build test ERROR on mptcp/export]
[also build test ERROR on mptcp/export-net linus/master v6.4 next-20230630]
[cannot apply to bpf-next/master bpf/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Geliang-Tang/Squash-to-selftests-bpf-add-two-mptcp-netns-helpers/20230701-205922
base:   https://github.com/multipath-tcp/mptcp_net-next.git export
patch link:    https://lore.kernel.org/r/daf3d1e26f19ee83b427ef9e17183cd09fc26de6.1688215769.git.geliang.tang%40suse.com
patch subject: [PATCH mptcp-next v2 2/4] bpf: Add bpf_mptcpify helper
config: nios2-randconfig-r021-20230701 (https://download.01.org/0day-ci/archive/20230702/202307020056.CI5KNYyK-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230702/202307020056.CI5KNYyK-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202307020056.CI5KNYyK-lkp@intel.com/

All errors (new ones prefixed by >>):

   nios2-linux-ld: kernel/bpf/cgroup.o: in function `cgroup_dev_func_proto':
   kernel/bpf/cgroup.c:1607: undefined reference to `bpf_mptcpify_proto'
>> nios2-linux-ld: kernel/bpf/cgroup.c:1607: undefined reference to `bpf_mptcpify_proto'
   nios2-linux-ld: kernel/bpf/cgroup.o: in function `cg_sockopt_func_proto':
   kernel/bpf/cgroup.c:2297: undefined reference to `bpf_mptcpify_proto'
   nios2-linux-ld: kernel/bpf/cgroup.c:2297: undefined reference to `bpf_mptcpify_proto'
   nios2-linux-ld: kernel/bpf/cgroup.o: in function `sysctl_func_proto':
   kernel/bpf/cgroup.c:2155: undefined reference to `bpf_mptcpify_proto'
   nios2-linux-ld: kernel/bpf/cgroup.o:kernel/bpf/cgroup.c:2155: more undefined references to `bpf_mptcpify_proto' follow

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

[PATCH mptcp-next v2 3/4] selftests/bpf: Test bpf_mptcpify helper

[Geliang Tang]

This patch tests the new helper bpf_mptcpify(). Store the new protocol
value after invoking the helper to a local BSS variable.

This is defined in a 'sock_create' SEC, so it will be invoked in
BPF_CGROUP_RUN_PROG_INET_SOCK() in inet_create().

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 tools/testing/selftests/bpf/bpf_tcp_helpers.h |  1 +
 tools/testing/selftests/bpf/progs/mptcpify.c  | 26 +++++++++++++++++++
 2 files changed, 27 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/progs/mptcpify.c

diff --git a/tools/testing/selftests/bpf/bpf_tcp_helpers.h b/tools/testing/selftests/bpf/bpf_tcp_helpers.h
index 72c618037386..f846d5d62529 100644
--- a/tools/testing/selftests/bpf/bpf_tcp_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_tcp_helpers.h
@@ -38,6 +38,7 @@ struct sock {
 #define sk_state		__sk_common.skc_state
 	unsigned long		sk_pacing_rate;
 	__u32			sk_pacing_status; /* see enum sk_pacing */
+	__u16			sk_protocol;
 } __attribute__((preserve_access_index));
 
 struct inet_sock {
diff --git a/tools/testing/selftests/bpf/progs/mptcpify.c b/tools/testing/selftests/bpf/progs/mptcpify.c
new file mode 100644
index 000000000000..f04b186b9c26
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/mptcpify.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2023, SUSE. */
+
+#include <sys/socket.h>
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_tcp_helpers.h"
+
+char _license[] SEC("license") = "GPL";
+__u16 protocol = 0;
+
+SEC("cgroup/sock_create")
+int sock(struct bpf_sock *ctx)
+{
+	struct sock *sk;
+
+	if (ctx->type != SOCK_STREAM)
+		return 1;
+
+	sk = bpf_mptcpify(ctx);
+	if (!sk)
+		return 1;
+
+	protocol = sk->sk_protocol;
+	return 1;
+}
-- 
2.35.3

[PATCH mptcp-next v2 4/4] selftests/bpf: Add mptcpify selftest

[Geliang Tang]

This patch extends the MPTCP test base, add a selftest test_mptcpify()
for the mptcpify case.

Open and load the mptcpify test prog to mptcpify the TCP sockets
dynamically, then use start_server() and connect_to_fd() to create a
TCP socket, but actually what's created is an MPTCP socket, which can
be verified through the stored local BSS variable.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/bpf/prog_tests/mptcp.c  | 87 +++++++++++++++++++
 1 file changed, 87 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
index e430bebebcf0..5f498bf5a677 100644
--- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
@@ -6,6 +6,7 @@
 #include "cgroup_helpers.h"
 #include "network_helpers.h"
 #include "mptcp_sock.skel.h"
+#include "mptcpify.skel.h"
 #include "mptcp_bpf_first.skel.h"
 #include "mptcp_bpf_bkup.skel.h"
 #include "mptcp_bpf_rr.skel.h"
@@ -13,6 +14,9 @@
 
 char NS_TEST[32];
 
+#ifndef IPPROTO_MPTCP
+#define IPPROTO_MPTCP 262
+#endif
 #ifndef TCP_CA_NAME_MAX
 #define TCP_CA_NAME_MAX	16
 #endif
@@ -200,6 +204,87 @@ static void test_base(void)
 	close(cgroup_fd);
 }
 
+static void send_byte(int fd)
+{
+	char b = 0x55;
+
+	ASSERT_EQ(write(fd, &b, sizeof(b)), 1, "send single byte");
+}
+
+static int verify_mptcpify(int protocol)
+{
+	char cmd[128];
+	int err = 0;
+
+	if (!ASSERT_EQ(protocol, IPPROTO_MPTCP, "unexpected protocol"))
+		err++;
+
+	snprintf(cmd, sizeof(cmd),
+		 "ip netns exec %s ss -tOni | grep -q tcp-ulp-mptcp",
+		 NS_TEST);
+	ASSERT_OK(system(cmd), "No tcp-ulp-mptcp found!");
+
+	return err;
+}
+
+static int run_mptcpify(int cgroup_fd)
+{
+	int server_fd, client_fd, err = 0;
+	struct mptcpify *mptcpify_skel;
+
+	mptcpify_skel = mptcpify__open_and_load();
+	if (!ASSERT_OK_PTR(mptcpify_skel, "skel_open_load"))
+		return -EIO;
+
+	mptcpify_skel->links.sock =
+		bpf_program__attach_cgroup(mptcpify_skel->progs.sock, cgroup_fd);
+	if (!ASSERT_OK_PTR(mptcpify_skel->links.sock, "cg_attach_sock"))
+		goto out;
+
+	/* without MPTCP */
+	server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);
+	if (!ASSERT_GE(server_fd, 0, "start_server")) {
+		err = -EIO;
+		goto out;
+	}
+
+	client_fd = connect_to_fd(server_fd, 0);
+	if (!ASSERT_GE(client_fd, 0, "connect to fd")) {
+		err = -EIO;
+		goto close_server;
+	}
+
+	send_byte(client_fd);
+	err += verify_mptcpify(mptcpify_skel->bss->protocol);
+
+	close(client_fd);
+close_server:
+	close(server_fd);
+out:
+	mptcpify__destroy(mptcpify_skel);
+	return err;
+}
+
+static void test_mptcpify(void)
+{
+	struct nstoken *nstoken = NULL;
+	int cgroup_fd;
+
+	cgroup_fd = test__join_cgroup("/mptcpify");
+	if (!ASSERT_GE(cgroup_fd, 0, "test__join_cgroup"))
+		return;
+
+	nstoken = create_netns();
+	if (!ASSERT_OK_PTR(nstoken, "create_netns"))
+		goto fail;
+
+	ASSERT_OK(run_mptcpify(cgroup_fd), "run_mptcpify");
+
+fail:
+	cleanup_netns(nstoken);
+	close(cgroup_fd);
+}
+
 static const unsigned int total_bytes = 10 * 1024 * 1024;
 static int stop, duration;
 
@@ -459,6 +544,8 @@ void test_mptcp(void)
 {
 	if (test__start_subtest("base"))
 		test_base();
+	if (test__start_subtest("mptcpify"))
+		test_mptcpify();
 	if (test__start_subtest("first"))
 		test_first();
 	if (test__start_subtest("bkup"))
-- 
2.35.3

Re: selftests/bpf: Add mptcpify selftest: Tests Results

[MPTCP CI]

Hi Geliang,

Thank you for your modifications, that's great!

Our CI did some validations and here is its report:

- KVM Validation: normal (except selftest_mptcp_join):
  - Success! ✅:
  - Task: https://cirrus-ci.com/task/6011347134054400
  - Summary: https://api.cirrus-ci.com/v1/artifact/task/6011347134054400/summary/summary.txt

- KVM Validation: debug (except selftest_mptcp_join):
  - Success! ✅:
  - Task: https://cirrus-ci.com/task/6574297087475712
  - Summary: https://api.cirrus-ci.com/v1/artifact/task/6574297087475712/summary/summary.txt

- KVM Validation: debug (only selftest_mptcp_join):
  - Success! ✅:
  - Task: https://cirrus-ci.com/task/4744709738856448
  - Summary: https://api.cirrus-ci.com/v1/artifact/task/4744709738856448/summary/summary.txt

- KVM Validation: normal (only selftest_mptcp_join):
  - Unstable: 1 failed test(s): selftest_mptcp_join 🔴:
  - Task: https://cirrus-ci.com/task/5448397180633088
  - Summary: https://api.cirrus-ci.com/v1/artifact/task/5448397180633088/summary/summary.txt

Initiator: Patchew Applier
Commits: https://github.com/multipath-tcp/mptcp_net-next/commits/c3be2bbd7a11


If there are some issues, you can reproduce them using the same environment as
the one used by the CI thanks to a docker image, e.g.:

    $ cd [kernel source code]
    $ docker run -v "${PWD}:${PWD}:rw" -w "${PWD}" --privileged --rm -it \
        --pull always mptcp/mptcp-upstream-virtme-docker:latest \
        auto-debug

For more details:

    https://github.com/multipath-tcp/mptcp-upstream-virtme-docker


Please note that despite all the efforts that have been already done to have a
stable tests suite when executed on a public CI like here, it is possible some
reported issues are not due to your modifications. Still, do not hesitate to
help us improve that ;-)

Cheers,
MPTCP GH Action bot
Bot operated by Matthieu Baerts (Tessares)