Re: [PATCH iproute2 v2] xfrm: enable to manage default policies

diff --git a/include/uapi/linux/xfrm.h b/include/uapi/linux/xfrm.h
index ecd06396eb16..378b4092f26a 100644
--- a/include/uapi/linux/xfrm.h
+++ b/include/uapi/linux/xfrm.h

@@ -213,13 +213,13 @@ enum {
 	XFRM_MSG_GETSPDINFO,
 #define XFRM_MSG_GETSPDINFO XFRM_MSG_GETSPDINFO
 
+	XFRM_MSG_MAPPING,
+#define XFRM_MSG_MAPPING XFRM_MSG_MAPPING
+
 	XFRM_MSG_SETDEFAULT,
 #define XFRM_MSG_SETDEFAULT XFRM_MSG_SETDEFAULT
 	XFRM_MSG_GETDEFAULT,
 #define XFRM_MSG_GETDEFAULT XFRM_MSG_GETDEFAULT
-
-	XFRM_MSG_MAPPING,
-#define XFRM_MSG_MAPPING XFRM_MSG_MAPPING
 	__XFRM_MSG_MAX
 };
 #define XFRM_MSG_MAX (__XFRM_MSG_MAX - 1)

@@ -514,9 +514,12 @@ struct xfrm_user_offload {
 #define XFRM_OFFLOAD_INBOUND	2
 
 struct xfrm_userpolicy_default {
-#define XFRM_USERPOLICY_DIRMASK_MAX	(sizeof(__u8) * 8)
-	__u8				dirmask;
-	__u8				action;
+#define XFRM_USERPOLICY_UNSPEC	0
+#define XFRM_USERPOLICY_BLOCK	1
+#define XFRM_USERPOLICY_ACCEPT	2
+	__u8				in;
+	__u8				fwd;
+	__u8				out;
 };
 
 /* backwards compatibility for userspace */

diff --git a/ip/xfrm_policy.c b/ip/xfrm_policy.c
index 7cc00e7c2f5b..744f331ff564 100644
--- a/ip/xfrm_policy.c
+++ b/ip/xfrm_policy.c

@@ -1124,6 +1126,121 @@ static int xfrm_spd_getinfo(int argc, char **argv)
 	return 0;
 }
 
+static int xfrm_spd_setdefault(int argc, char **argv)
+{
+	struct rtnl_handle rth;
+	struct {
+		struct nlmsghdr			n;
+		struct xfrm_userpolicy_default  up;
+	} req = {
+		.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct xfrm_userpolicy_default)),
+		.n.nlmsg_flags = NLM_F_REQUEST,
+		.n.nlmsg_type = XFRM_MSG_SETDEFAULT,
+	};
+
+	while (argc > 0) {
+		if (strcmp(*argv, "in") == 0) {
+			if (req.up.in)
+				duparg("in", *argv);
+
+			NEXT_ARG();
+			if (strcmp(*argv, "block") == 0)
+				req.up.in = XFRM_USERPOLICY_BLOCK;
+			else if (strcmp(*argv, "accept") == 0)
+				req.up.in = XFRM_USERPOLICY_ACCEPT;
+			else
+				invarg("in policy value is invalid", *argv);
+		} else if (strcmp(*argv, "fwd") == 0) {
+			if (req.up.fwd)
+				duparg("fwd", *argv);
+
+			NEXT_ARG();
+			if (strcmp(*argv, "block") == 0)
+				req.up.fwd = XFRM_USERPOLICY_BLOCK;
+			else if (strcmp(*argv, "accept") == 0)
+				req.up.fwd = XFRM_USERPOLICY_ACCEPT;
+			else
+				invarg("fwd policy value is invalid", *argv);
+		} else if (strcmp(*argv, "out") == 0) {
+			if (req.up.out)
+				duparg("out", *argv);
+
+			NEXT_ARG();
+			if (strcmp(*argv, "block") == 0)
+				req.up.out = XFRM_USERPOLICY_BLOCK;
+			else if (strcmp(*argv, "accept") == 0)
+				req.up.out = XFRM_USERPOLICY_ACCEPT;
+			else
+				invarg("out policy value is invalid", *argv);
+		} else {
+			invarg("unknown direction", *argv);
+		}
+
+		argc--; argv++;
+	}
+
+	if (rtnl_open_byproto(&rth, 0, NETLINK_XFRM) < 0)
+		exit(1);
+
+	if (rtnl_talk(&rth, &req.n, NULL) < 0)
+		exit(2);
+
+	rtnl_close(&rth);
+
+	return 0;
+}
+
+int xfrm_policy_default_print(struct nlmsghdr *n, FILE *fp)
+{
+	struct xfrm_userpolicy_default *up = NLMSG_DATA(n);
+	int len = n->nlmsg_len - NLMSG_SPACE(sizeof(*up));
+
+	if (len < 0) {
+		fprintf(stderr,
+			"BUG: short nlmsg len %u (expect %lu) for XFRM_MSG_GETDEFAULT\n",
+			n->nlmsg_len, NLMSG_SPACE(sizeof(*up)));
+		return -1;
+	}
+
+	fprintf(fp, "Default policies:\n");
+	fprintf(fp, " in:  %s\n",
+		up->in == XFRM_USERPOLICY_BLOCK ? "block" : "accept");
+	fprintf(fp, " fwd: %s\n",
+		up->fwd == XFRM_USERPOLICY_BLOCK ? "block" : "accept");
+	fprintf(fp, " out: %s\n",
+		up->out == XFRM_USERPOLICY_BLOCK ? "block" : "accept");
+	fflush(fp);
+
+	return 0;
+}
+