From a31ac06cb2c2f51e2a5e404f06032b702d8d1ebe Mon Sep 17 00:00:00 2001
From: Neil Alexander <neilalexander@users.noreply.github.com>
Date: Sat, 20 Jul 2019 10:59:45 +0100
Subject: [PATCH] Initial FreeBSD/OpenBSD/NetBSD support (doesn't have syscalls
 for interface config yet)

---
 params_bsd.go     | 20 ++++++++++++++++++++
 params_others.go  |  2 +-
 syscalls_bsd.go   | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 syscalls_other.go |  2 +-
 4 files changed, 69 insertions(+), 2 deletions(-)
 create mode 100644 params_bsd.go
 create mode 100644 syscalls_bsd.go

diff --git a/params_bsd.go b/params_bsd.go
new file mode 100644
index 0000000..aca5cee
--- /dev/null
+++ b/params_bsd.go
@@ -0,0 +1,20 @@
+// +build openbsd freebsd netbsd
+
+package water
+
+// PlatformSpecificParams defines parameters in Config that are specific to
+// Linux. A zero-value of such type is valid, yielding an interface
+// with OS defined name.
+type PlatformSpecificParams struct {
+	// Name is the name to be set for the interface to be created. This overrides
+	// the default name assigned by OS such as tap0 or tun0. A zero-value of this
+	// field, i.e. an empty string, indicates that the default name should be
+	// used.
+	Name string
+}
+
+func defaultPlatformSpecificParams() PlatformSpecificParams {
+	return PlatformSpecificParams{
+		Name: "/dev/tap0",
+	}
+}
diff --git a/params_others.go b/params_others.go
index c5c4f6e..574aeb2 100644
--- a/params_others.go
+++ b/params_others.go
@@ -1,4 +1,4 @@
-// +build !linux,!darwin,!windows
+// +build !linux,!darwin,!windows,!freebsd,!netbsd,!openbsd
 
 package water
 
diff --git a/syscalls_bsd.go b/syscalls_bsd.go
new file mode 100644
index 0000000..70af690
--- /dev/null
+++ b/syscalls_bsd.go
@@ -0,0 +1,47 @@
+// +build openbsd freebsd netbsd
+
+package water
+
+import (
+	"errors"
+	"os"
+)
+
+func openDev(config Config) (ifce *Interface, err error) {
+	switch config.Name[:8] {
+	case "/dev/tap":
+		return newTAP(config)
+	case "/dev/tun":
+		return newTUN(config)
+	default:
+		return nil, errors.New("unrecognized driver")
+	}
+}
+
+func newTAP(config Config) (ifce *Interface, err error) {
+	if config.Name[:8] != "/dev/tap" {
+		panic("TUN/TAP name must be in format /dev/tunX or /dev/tapX")
+	}
+
+	file, err := os.OpenFile(config.Name, os.O_RDWR, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	ifce = &Interface{isTAP: true, ReadWriteCloser: file, name: config.Name[5:]}
+	return
+}
+
+func newTUN(config Config) (ifce *Interface, err error) {
+	if config.Name[:8] != "/dev/tun" {
+		panic("TUN/TAP name must be in format /dev/tunX or /dev/tapX")
+	}
+
+	file, err := os.OpenFile(config.Name, os.O_RDWR, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	ifce = &Interface{isTAP: false, ReadWriteCloser: file, name: config.Name[5:]}
+	return
+}
diff --git a/syscalls_other.go b/syscalls_other.go
index c5ed1b3..536c388 100644
--- a/syscalls_other.go
+++ b/syscalls_other.go
@@ -1,4 +1,4 @@
-// +build !linux,!darwin,!windows
+// +build !linux,!darwin,!windows,!freebsd,!netbsd,!openbsd
 
 package water