diff --git a/man/systemd.netdev.xml b/man/systemd.netdev.xml
index 449b23d5ac..ff0bdee51f 100644
--- a/man/systemd.netdev.xml
+++ b/man/systemd.netdev.xml
@@ -1994,7 +1994,7 @@
InterfaceId=
Sets the ID/key of the xfrm interface which needs to be associated with a SA/policy.
- Can be decimal or hexadecimal, valid range is 0-0xffffffff, defaults to 0.
+ Can be decimal or hexadecimal, valid range is 1-0xffffffff. This is mandatory.
diff --git a/src/network/netdev/xfrm.c b/src/network/netdev/xfrm.c
index 05844b8321..a961d8fef2 100644
--- a/src/network/netdev/xfrm.c
+++ b/src/network/netdev/xfrm.c
@@ -14,6 +14,7 @@ static int xfrm_fill_message_create(NetDev *netdev, Link *link, sd_netlink_messa
x = XFRM(netdev);
+ assert(x);
assert(link || x->independent);
r = sd_netlink_message_append_u32(message, IFLA_XFRM_LINK, link ? link->ifindex : LOOPBACK_IFINDEX);
@@ -27,10 +28,28 @@ static int xfrm_fill_message_create(NetDev *netdev, Link *link, sd_netlink_messa
return 0;
}
+static int xfrm_verify(NetDev *netdev, const char *filename) {
+ Xfrm *x;
+
+ assert(netdev);
+ assert(filename);
+
+ x = XFRM(netdev);
+
+ assert(x);
+
+ if (x->if_id == 0)
+ return log_netdev_warning_errno(netdev, SYNTHETIC_ERRNO(EINVAL),
+ "%s: Xfrm interface ID cannot be zero.", filename);
+
+ return 0;
+}
+
const NetDevVTable xfrm_vtable = {
.object_size = sizeof(Xfrm),
.sections = NETDEV_COMMON_SECTIONS "Xfrm\0",
.fill_message_create = xfrm_fill_message_create,
+ .config_verify = xfrm_verify,
.create_type = NETDEV_CREATE_STACKED,
.iftype = ARPHRD_NONE,
};