diff --git a/tools/git/git.go b/tools/git/git.go
new file mode 100644
index 00000000..964ed43a
--- /dev/null
+++ b/tools/git/git.go
@@ -0,0 +1,58 @@
+package git
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+const (
+	VersionUndefined = "undefined"
+)
+
+func getRepoRoot() string {
+	GOPATH := os.Getenv("GOPATH")
+	return filepath.Join(GOPATH, "src", "github.com", "v2ray", "v2ray-core")
+}
+
+func RevParse(args ...string) (string, error) {
+	args = append([]string{"rev-parse"}, args...)
+	cmd := exec.Command("git", args...)
+	cmd.Dir = getRepoRoot()
+	output, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(output)), nil
+}
+
+func NameRev(args ...string) (string, error) {
+	args = append([]string{"name-rev"}, args...)
+	cmd := exec.Command("git", args...)
+	cmd.Dir = getRepoRoot()
+	output, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(output)), nil
+}
+
+func RepoVersion(rev string) (string, error) {
+	rev, err := RevParse(rev)
+	if err != nil {
+		return "", err
+	}
+	version, err := NameRev("name-rev", "--tags", "--name-only", rev)
+	if err != nil {
+		return "", err
+	}
+	if strings.HasSuffix(version, "^0") {
+		version = version[:len(version)-2]
+	}
+	return version, nil
+}
+
+func RepoVersionHead() (string, error) {
+	return RepoVersion("HEAD")
+}
diff --git a/tools/git/git_test.go b/tools/git/git_test.go
new file mode 100644
index 00000000..d7a17307
--- /dev/null
+++ b/tools/git/git_test.go
@@ -0,0 +1,31 @@
+package git
+
+import (
+	"testing"
+
+	"github.com/v2ray/v2ray-core/testing/unit"
+)
+
+func TestRevParse(t *testing.T) {
+	assert := unit.Assert(t)
+
+	rev, err := RevParse("HEAD")
+	assert.Error(err).IsNil()
+	assert.Int(len(rev)).GreaterThan(0)
+
+	rev, err = RevParse("v0.8")
+	assert.Error(err).IsNil()
+	assert.String(rev).Equals("de7a1d30c3e6bda6a1297b5815369fcfa0e74f0e")
+}
+
+func TestRepoVersion(t *testing.T) {
+	assert := unit.Assert(t)
+
+	version, err := RepoVersionHead()
+	assert.Error(err).IsNil()
+	assert.Int(len(version)).GreaterThan(0)
+
+	version, err = RepoVersion("de7a1d30c3e6bda6a1297b5815369fcfa0e74f0e")
+	assert.Error(err).IsNil()
+	assert.String(version).Equals("v0.8")
+}