1 files changed, 38 insertions, 0 deletions
diff --git a/src/libbcnm/bcnm_if_link_init.c b/src/libbcnm/bcnm_if_link_init.c
new file mode 100644
index 0000000..dad93fd
--- /dev/null
+++ b/src/libbcnm/bcnm_if_link_init.c
@@ -0,0 +1,38 @@
+/* ISC license. */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <unistd.h>
+#include <errno.h>
+#include <sys/socket.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#include <bcnm/if.h>
+
+int bcnm_if_link_init (unsigned int kbufsz)
+{
+  struct sockaddr_nl nl =
+  {
+    .nl_family = AF_NETLINK,
+    .nl_pad = 0,
+    .nl_groups = RTNLGRP_LINK,
+    .nl_pid = 0
+  } ;
+  int fd = socket(AF_NETLINK, SOCK_DGRAM | SOCK_NONBLOCK | SOCK_CLOEXEC, NETLINK_ROUTE) ;
+  if (fd < 0) return -1 ;
+  if (bind(fd, (struct sockaddr *)&nl, sizeof(struct sockaddr_nl)) < 0) goto err ;
+  if (setsockopt(fd, SOL_SOCKET, SO_RCVBUFFORCE, &kbufsz, sizeof(unsigned int)) < 0)
+  {
+    if (errno != EPERM
+     || setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &kbufsz, sizeof(unsigned int)) < 0) goto err ;
+  }
+  return fd ;
+
+ err:
+  close(fd) ;
+  return -1 ;
+}
+