tools/mptcpify: mask socket type before matching SOCK_STREAM

The hook receives the raw type with SOCK_NONBLOCK/SOCK_CLOEXEC still
ORed in, so callers like curl that pass SOCK_STREAM|SOCK_NONBLOCK never
match "type == SOCK_STREAM" and aren't converted to MPTCP. Use
(type & SOCK_TYPE_MASK) == SOCK_STREAM instead.

Suggested-by: Guillaume @layus Maudoux <layus.on@gmail.com>
Signed-off-by: Gang Yan <yangang@kylinos.cn>

Author: Dwyane-Yan

tools/mptcpify.py

@@ -48,6 +48,10 @@ class app_name(ct.Structure):
 #include <uapi/linux/in.h>
 #include <linux/string.h>
 
+#ifndef SOCK_TYPE_MASK
+#define SOCK_TYPE_MASK 0xf
+#endif
+
 struct app_name {
     char name[TASK_COMM_LEN];
 };
@@ -63,7 +67,7 @@ class app_name(ct.Structure):
     bpf_get_current_comm(&target.name, TASK_COMM_LEN);
 
     if ((family == AF_INET || family == AF_INET6) &&
-        type == SOCK_STREAM &&
+        (type & SOCK_TYPE_MASK) == SOCK_STREAM &&
         (!protocol || protocol == IPPROTO_TCP) &&
         (mode && *mode == 0 || support_apps.lookup(&target)))
         return IPPROTO_MPTCP;