[PATCH iproute2-next v3 2/3] mptcp: add fullmesh support for setting flags

[Geliang Tang <geliang.tang@suse.com>]

A pair of new flags, fullmesh and nofullmesh, had been added in the
setting flags of MPTCP PM netlink in kernel space recently by the commit
73c762c1f07d ("mptcp: set fullmesh flag in pm_netlink").

This patch added the corresponding logic to pass these two flags to the
netlink in user space.

These new flags can be used like this:

 ip mptcp endpoint change id 1 fullmesh
 ip mptcp endpoint change id 1 nofullmesh
 ip mptcp endpoint change id 1 backup fullmesh
 ip mptcp endpoint change id 1 nobackup nofullmesh

Here's an example of setting fullmesh flags:

 > sudo ip mptcp endpoint add 10.0.2.1 subflow
 > sudo ip mptcp endpoint show
 10.0.2.1 id 1 subflow
 > sudo ip mptcp endpoint change id 1 fullmesh
 > sudo ip mptcp endpoint show
 10.0.2.1 id 1 subflow fullmesh
 > sudo ip mptcp endpoint change id 1 nofullmesh
 > sudo ip mptcp endpoint show
 10.0.2.1 id 1 subflow

It can be seen that 'ip mptcp endpoint show' already supports showing
the fullmesh flag.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 ip/ipmptcp.c        | 20 ++++++++++++--------
 man/man8/ip-mptcp.8 |  8 ++++++--
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/ip/ipmptcp.c b/ip/ipmptcp.c
index 5682c7df..c7b63761 100644
--- a/ip/ipmptcp.c
+++ b/ip/ipmptcp.c
@@ -25,14 +25,15 @@ static void usage(void)
 		"Usage:	ip mptcp endpoint add ADDRESS [ dev NAME ] [ id ID ]\n"
 		"				      [ port NR ] [ FLAG-LIST ]\n"
 		"	ip mptcp endpoint delete id ID [ ADDRESS ]\n"
-		"	ip mptcp endpoint change id ID [ backup | nobackup ]\n"
+		"	ip mptcp endpoint change id ID CHANGE-OPT\n"
 		"	ip mptcp endpoint show [ id ID ]\n"
 		"	ip mptcp endpoint flush\n"
 		"	ip mptcp limits set [ subflows NR ] [ add_addr_accepted NR ]\n"
 		"	ip mptcp limits show\n"
 		"	ip mptcp monitor\n"
 		"FLAG-LIST := [ FLAG-LIST ] FLAG\n"
-		"FLAG  := [ signal | subflow | backup | fullmesh ]\n");
+		"FLAG  := [ signal | subflow | backup | fullmesh ]\n"
+		"CHANGE-OPT := [ backup | nobackup | fullmesh | nofullmesh ]\n");
 
 	exit(-1);
 }
@@ -46,7 +47,7 @@ static int genl_family = -1;
 	GENL_REQUEST(_req, MPTCP_BUFLEN, genl_family, 0,	\
 		     MPTCP_PM_VER, _cmd, _flags)
 
-#define MPTCP_PM_ADDR_FLAG_NOBACKUP 0x0
+#define MPTCP_PM_ADDR_FLAG_NONE 0x0
 
 /* Mapping from argument to address flag mask */
 static const struct {
@@ -57,7 +58,8 @@ static const struct {
 	{ "subflow",		MPTCP_PM_ADDR_FLAG_SUBFLOW },
 	{ "backup",		MPTCP_PM_ADDR_FLAG_BACKUP },
 	{ "fullmesh",		MPTCP_PM_ADDR_FLAG_FULLMESH },
-	{ "nobackup",		MPTCP_PM_ADDR_FLAG_NOBACKUP }
+	{ "nobackup",		MPTCP_PM_ADDR_FLAG_NONE },
+	{ "nofullmesh",		MPTCP_PM_ADDR_FLAG_NONE }
 };
 
 static void print_mptcp_addr_flags(unsigned int flags)
@@ -102,6 +104,7 @@ static int get_flags(const char *arg, __u32 *flags)
 
 static int mptcp_parse_opt(int argc, char **argv, struct nlmsghdr *n, int cmd)
 {
+	bool setting = cmd == MPTCP_PM_CMD_SET_FLAGS;
 	bool adding = cmd == MPTCP_PM_CMD_ADD_ADDR;
 	bool deling = cmd == MPTCP_PM_CMD_DEL_ADDR;
 	struct rtattr *attr_addr;
@@ -121,10 +124,11 @@ static int mptcp_parse_opt(int argc, char **argv, struct nlmsghdr *n, int cmd)
 			    (flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
 				invarg("flags mustn't have both signal and fullmesh", *argv);
 
-			/* allow changing the 'backup' flag only */
-			if (cmd == MPTCP_PM_CMD_SET_FLAGS &&
-			    (flags & ~MPTCP_PM_ADDR_FLAG_BACKUP))
-				invarg("invalid flags\n", *argv);
+			/* allow changing the 'backup' and 'fullmesh' flags only */
+			if (setting &&
+			    (flags & ~(MPTCP_PM_ADDR_FLAG_BACKUP |
+				       MPTCP_PM_ADDR_FLAG_FULLMESH)))
+				invarg("invalid flags, backup and fullmesh only", *argv);
 
 		} else if (matches(*argv, "id") == 0) {
 			NEXT_ARG();
diff --git a/man/man8/ip-mptcp.8 b/man/man8/ip-mptcp.8
index 0e789225..bddbff3c 100644
--- a/man/man8/ip-mptcp.8
+++ b/man/man8/ip-mptcp.8
@@ -41,7 +41,7 @@ ip-mptcp \- MPTCP path manager configuration
 .BR "ip mptcp endpoint change id "
 .I ID
 .RB "[ "
-.I BACKUP-OPT
+.I CHANGE-OPT
 .RB "] "
 
 .ti -8
@@ -68,10 +68,14 @@ ip-mptcp \- MPTCP path manager configuration
 .RB  "]"
 
 .ti -8
-.IR BACKUP-OPT " := ["
+.IR CHANGE-OPT " := ["
 .B backup
 .RB "|"
 .B nobackup
+.RB "|"
+.B fullmesh
+.RB "|"
+.B nofullmesh
 .RB  "]"
 
 .ti -8
-- 
2.34.1