From 7f708e48c2c69c7e18ebe88c8dbb6f7a0a1d3577 Mon Sep 17 00:00:00 2001
From: Simon Thulbourn <simon+github@thulbourn.com>
Date: Fri, 23 Jan 2015 22:28:49 +0000
Subject: [PATCH] Valid hostname check

Signed-off-by: Simon Thulbourn <simon+github@thulbourn.com>
---
 host.go      | 11 +++++++++--
 host_test.go | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 2 deletions(-)
 create mode 100644 host_test.go

diff --git a/host.go b/host.go
index 61f4145c9c..2475cabca0 100644
--- a/host.go
+++ b/host.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"net"
@@ -16,8 +17,9 @@ import (
 )
 
 var (
-	validHostNameChars   = `[a-zA-Z0-9_]`
+	validHostNameChars   = `[a-zA-Z0-9\-\.]`
 	validHostNamePattern = regexp.MustCompile(`^` + validHostNameChars + `+$`)
+	ErrInvalidHostname   = errors.New("Invalid hostname specified")
 )
 
 type Host struct {
@@ -78,7 +80,7 @@ func LoadHost(name string, storePath string) (*Host, error) {
 
 func ValidateHostName(name string) (string, error) {
 	if !validHostNamePattern.MatchString(name) {
-		return name, fmt.Errorf("Invalid host name %q, it must match %s", name, validHostNamePattern)
+		return name, ErrInvalidHostname
 	}
 	return name, nil
 }
@@ -262,6 +264,11 @@ DOCKER_TLS=no`, opts, machineCaCertPath, machineServerCertPath, machineServerKey
 }
 
 func (h *Host) Create(name string) error {
+	name, err := ValidateHostName(name)
+	if err != nil {
+		return err
+	}
+
 	if err := h.Driver.Create(); err != nil {
 		return err
 	}
diff --git a/host_test.go b/host_test.go
new file mode 100644
index 0000000000..c08d24c2e0
--- /dev/null
+++ b/host_test.go
@@ -0,0 +1,39 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestValidateHostnameValid(t *testing.T) {
+	hosts := []string{
+		"zomg",
+		"test-ing",
+		"some.h0st",
+	}
+
+	for _, v := range hosts {
+		h, err := ValidateHostName(v)
+		if err != nil {
+			t.Fatal("Invalid hostname")
+		}
+
+		if h != v {
+			t.Fatal("Hostname doesn't match")
+		}
+	}
+}
+
+func TestValidateHostnameInvalid(t *testing.T) {
+	hosts := []string{
+		"zom_g",
+		"test$ing",
+		"some😄host",
+	}
+
+	for _, v := range hosts {
+		_, err := ValidateHostName(v)
+		if err == nil {
+			t.Fatal("No error returned")
+		}
+	}
+}