dhcpv4: Move BindToInterface to interfaces package

This moves the implementations of the BindToInterface to the interfaces/
package, since they aren't ipv4-specific.
The BindToInterface function remains in dhcpv4 (simply wraps the one in
interfaces) to keep backwards-compatibility

Additionally, fold bindtodevice_darwin into bindtodevice_bsd: darwin is
mostly a BSD, and happens to support IP_RECVIF, so use that instead of
IP_BOUND_IF, which only affects sends, not receives according to the
code comments in bsd/netinet/ip_output.c as well as being v4-only

Signed-off-by: Anatole Denis <natolumin@unverle.fr>

4 files changed, 10 insertions, 46 deletions

diff --git a/dhcpv4/bindtodevice_bsd.go b/dhcpv4/bindtodevice_bsd.go
deleted file mode 100644
index 0f1b581..0000000
--- a/dhcpv4/bindtodevice_bsd.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// +build freebsd openbsd netbsd
-
-package dhcpv4
-
-import (
-	"net"
-	"syscall"
-)
-
-// BindToInterface emulates linux's SO_BINDTODEVICE option for a socket by using
-// IP_RECVIF.
-func BindToInterface(fd int, ifname string) error {
-	iface, err := net.InterfaceByName(ifname)
-	if err != nil {
-		return err
-	}
-	return syscall.SetsockoptInt(fd, syscall.IPPROTO_IP, syscall.IP_RECVIF, iface.Index)
-}
diff --git a/dhcpv4/bindtodevice_darwin.go b/dhcpv4/bindtodevice_darwin.go
deleted file mode 100644
index 3a1406b..0000000
--- a/dhcpv4/bindtodevice_darwin.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// +build darwin
-
-package dhcpv4
-
-import (
-	"net"
-
-	"golang.org/x/sys/unix"
-)
-
-// BindToInterface emulates linux's SO_BINDTODEVICE option for a socket by using
-// SO_IP_BOUND_IF.
-func BindToInterface(fd int, ifname string) error {
-	iface, err := net.InterfaceByName(ifname)
-	if err != nil {
-		return err
-	}
-	return unix.SetsockoptInt(fd, unix.IPPROTO_IP, unix.IP_BOUND_IF, iface.Index)
-}
diff --git a/dhcpv4/bindtodevice_linux.go b/dhcpv4/bindtodevice_linux.go
deleted file mode 100644
index c1ae025..0000000
--- a/dhcpv4/bindtodevice_linux.go
+++ /dev/null
@@ -1,9 +0,0 @@
-// +build linux
-
-package dhcpv4
-
-import "golang.org/x/sys/unix"
-
-func BindToInterface(fd int, ifname string) error {
-	return unix.BindToDevice(fd, ifname)
-}
diff --git a/dhcpv4/bindtointerface.go b/dhcpv4/bindtointerface.go
new file mode 100644
index 0000000..dbe8fbc
--- /dev/null
+++ b/dhcpv4/bindtointerface.go
@@ -0,0 +1,10 @@
+package dhcpv4
+
+import (
+	"github.com/insomniacslk/dhcp/interfaces"
+)
+
+// BindToInterface (deprecated) redirects to interfaces.BindToInterface
+func BindToInterface(fd int, ifname string) error {
+	return interfaces.BindToInterface(fd, ifname)
+}