internal/freebsd: add initial version of FreeBSD support

Signed-off-by: Steffen Vogel <post@steffenvogel.de>
WireGuard · stv0g · Oct 9, 2022 · Oct 9, 2022 · Oct 10, 2022 · Oct 16, 2022
commit b76f2e2af4b609f72072dab5d16dcc90f214c149
diff --git a/internal/wgfreebsd/client_freebsd.go b/internal/wgfreebsd/client_freebsd.go
diff --git a/internal/wgfreebsd/doc.go b/internal/wgfreebsd/doc.go
@@ -0,0 +1,6 @@
+// Package wgfreebsd provides internal access to FreeBSD's WireGuard
+// ioctl interface.
+//
+// This package is internal-only and not meant for end users to consume.
+// Please use package wgctrl (an abstraction over this package) instead.
+package wgfreebsd
diff --git a/internal/wgfreebsd/internal/nv/decode.go b/internal/wgfreebsd/internal/nv/decode.go
@@ -0,0 +1,71 @@
+//go:build freebsd
+// +build freebsd
+
+package nv
+
+// #cgo LDFLAGS: -lnv
+// #include <sys/nv.h>
+import "C"
+
+import (
+	"unsafe"
+)
+
+// Unmarshal decodes a FreeBSD name-value list (nv(9)) to a Go map
+func Unmarshal(d []byte, out List) error {
+	sz := C.ulong(len(d))
+	dp := unsafe.Pointer(&d[0])
+	nvl := C.nvlist_unpack(dp, sz, 0)
+
+	return unmarshal(nvl, out)
+}
+
+func unmarshal(nvl *C.struct_nvlist, out List) error {
+	// For debugging
+	// C.nvlist_dump(nvl, C.int(os.Stdout.Fd()))
+
+	var cookie unsafe.Pointer
+	for {
+		var typ C.int
+		ckey := C.nvlist_next(nvl, &typ, &cookie)
+		if ckey == nil {
+			break
+		}
+
+		var sz C.size_t
+		var value interface{}
+		switch typ {
+		case C.NV_TYPE_BINARY:
+			v := C.nvlist_get_binary(nvl, ckey, &sz)
+			value = C.GoBytes(v, C.int(sz))
+
+		case C.NV_TYPE_BOOL:
+			value = C.nvlist_get_bool(nvl, ckey)
+
+		case C.NV_TYPE_NUMBER:
+			v := C.nvlist_get_number(nvl, ckey)
+			value = uint64(v)
+
+		case C.NV_TYPE_NVLIST_ARRAY:
+			items := []List{}
+
+			nvlSubListsBuf := C.nvlist_get_nvlist_array(nvl, ckey, &sz)
+			nvlSubLists := unsafe.Slice(nvlSubListsBuf, sz)
+			for _, nvlSubList := range nvlSubLists {
+				item := map[string]interface{}{}
+				if err := unmarshal(nvlSubList, item); err != nil {
+					return err
+				}
+
+				items = append(items, item)
+			}
+
+			value = items
+		}
+
+		name := C.GoString(ckey)
+		out[name] = value
+	}
+
+	return nil
+}
diff --git a/internal/wgfreebsd/internal/nv/doc.go b/internal/wgfreebsd/internal/nv/doc.go
@@ -0,0 +1,3 @@
+// Package nv marshals and unmarshals Go maps to/from FreeBSDs nv(9) name/value lists
+// See: https://www.freebsd.org/cgi/man.cgi?query=nv&sektion=9
+package nv
diff --git a/internal/wgfreebsd/internal/nv/encode.go b/internal/wgfreebsd/internal/nv/encode.go
@@ -0,0 +1,75 @@
+//go:build freebsd
+// +build freebsd
+
+package nv
+
+/*
+#cgo LDFLAGS: -lnv
+#include <stdlib.h>
+#include <sys/nv.h>
+
+// For sizeof(*struct nvlist)
+typedef struct nvlist *nvlist_ptr;
+*/
+import "C"
+
+import (
+	"unsafe"
+)
+
+// Marshal encodes a Go map to a FreeBSD name-value list (nv(9))
+func Marshal(m List) (*byte, int, error) {
+	nvl, err := marshal(m)
+	if err != nil {
+		return nil, -1, err
+	}
+
+	// For debugging
+	// C.nvlist_dump(nvl, C.int(os.Stdout.Fd()))
+
+	var sz C.size_t
+	buf := C.nvlist_pack(nvl, &sz)
+
+	return (*byte)(buf), int(sz), nil
+}
+
+func marshal(m List) (nvl *C.struct_nvlist, err error) {
+	nvl = C.nvlist_create(0)
+
+	for key, value := range m {
+		ckey := C.CString(key)
+
+		switch value := value.(type) {
+		case bool:
+			C.nvlist_add_bool(nvl, ckey, C.bool(value))
+
+		case uint64:
+			C.nvlist_add_number(nvl, ckey, C.ulong(value))
+
+		case []byte:
+			sz := len(value)
+			ptr := C.CBytes(value)
+			C.nvlist_add_binary(nvl, ckey, ptr, C.size_t(sz))
+			C.free(ptr)
+
+		case []List:
+			sz := len(value)
+			buf := C.malloc(C.size_t(C.sizeof_nvlist_ptr * sz))
+			items := (*[1<<30 - 1]*C.struct_nvlist)(buf)
+
+			for i, val := range value {
+				if items[i], err = marshal(val); err != nil {
+					C.free(unsafe.Pointer(ckey))
+					return nil, err
+				}
+			}
+
+			C.nvlist_add_nvlist_array(nvl, ckey, (**C.struct_nvlist)(buf), C.size_t(sz))
+			C.free(buf)
+		}
+
+		C.free(unsafe.Pointer(ckey))
+	}
+
+	return
+}
diff --git a/internal/wgfreebsd/internal/nv/nvlist_test.go b/internal/wgfreebsd/internal/nv/nvlist_test.go
@@ -0,0 +1,45 @@
+//go:build freebsd
+// +build freebsd
+
+package nv_test
+
+import (
+	"fmt"
+	"testing"
+	"unsafe"
+
+	"golang.zx2c4.com/wireguard/wgctrl/internal/wgfreebsd/internal/nv"
+)
+
+func TestMarshaling(t *testing.T) {
+	m1 := nv.List{
+		"number":  uint64(0x1234),
+		"boolean": true,
+		"binary":  []byte{0xA, 0xB, 0xC, 0xD},
+		"array_of_nvlists": []nv.List{
+			{
+				"a": uint64(1),
+			},
+			{
+				"b": uint64(2),
+			},
+		},
+	}
+
+	buf, sz, err := nv.Marshal(m1)
+	if err != nil {
+		t.Fatalf("Failed to marshal: %s", err)
+	}
+
+	m2 := nv.List{}
+	buf2 := unsafe.Slice(buf, sz)
+
+	err = nv.Unmarshal(buf2, m2)
+	if err != nil {
+		t.Fatalf("Failed to marshal: %s", err)
+	}
+
+	if fmt.Sprint(m1) != fmt.Sprint(m2) {
+		t.Fatalf("unequal: %+#v != %+#v", m1, m2)
+	}
+}
diff --git a/internal/wgfreebsd/internal/nv/types.go b/internal/wgfreebsd/internal/nv/types.go
@@ -0,0 +1,6 @@
+//go:build freebsd
+// +build freebsd
+
+package nv
+
+type List map[string]interface{}
diff --git a/internal/wgfreebsd/internal/wgh/defs.go b/internal/wgfreebsd/internal/wgh/defs.go
@@ -0,0 +1,51 @@
+//go:build ignore
+// +build ignore
+
+// TODO(mdlayher): attempt to integrate into x/sys/unix infrastructure.
+
+package wgh
+
+/*
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <sys/sockio.h>
+#include <time.h>
+#include <net/if.h>
+
+struct wg_data_io {
+	char wgd_name[IFNAMSIZ];
+	void *wgd_data;
+	size_t wgd_size;
+};
+
+// This is a copy of ifgroupreq but the union's *ifg_req variant is broken out
+// into an explicit field, and the other variant is omitted and replaced with
+// struct padding to the expected size.
+#undef ifgr_groups
+struct go_ifgroupreq {
+	char	ifgr_name[IFNAMSIZ];
+	u_int	ifgr_len;
+	char    ifgr_pad1[-1 * (4 - sizeof(void*))];
+	struct	ifg_req *ifgr_groups;
+	char    ifgr_pad2[16 - sizeof(void*)];
+};
+
+#define SIOCSWG _IOWR('i', 210, struct wg_data_io)
+#define SIOCGWG _IOWR('i', 211, struct wg_data_io)
+*/
+import "C"
+
+// Interface group types and constants.
+
+const (
+	SizeofIfgreq = C.sizeof_struct_ifg_req
+
+	SIOCGWG = C.SIOCGWG
+	SIOCSWG = C.SIOCSWG
+)
+
+type Ifgroupreq C.struct_go_ifgroupreq
+
+type Ifgreq C.struct_ifg_req
+
+type WGDataIO C.struct_wg_data_io
diff --git a/internal/wgfreebsd/internal/wgh/defs_freebsd_386.go b/internal/wgfreebsd/internal/wgh/defs_freebsd_386.go
diff --git a/internal/wgfreebsd/internal/wgh/defs_freebsd_amd64.go b/internal/wgfreebsd/internal/wgh/defs_freebsd_amd64.go
diff --git a/internal/wgfreebsd/internal/wgh/defs_freebsd_arm.go b/internal/wgfreebsd/internal/wgh/defs_freebsd_arm.go
diff --git a/internal/wgfreebsd/internal/wgh/defs_freebsd_arm64.go b/internal/wgfreebsd/internal/wgh/defs_freebsd_arm64.go
diff --git a/internal/wgfreebsd/internal/wgh/doc.go b/internal/wgfreebsd/internal/wgh/doc.go
@@ -0,0 +1,3 @@
+// Package wgh is an auto-generated package which contains constants and
+// types used to access WireGuard information using ioctl calls.
+package wgh