Use spec.ip as default listen address for bosh-dns-windows

In 1.18 the default listen address was changed to 127.0.0.1 so the dns
server would only be available locally on each VM, to match the default
behaviour on linux. When two non-loopback non-tunnel network interfaces
are present bosh-dns-windows failed to start due to how the
implementation of `windows_manager.go` tries to identify the "primary"
adapter by matching the IP address.

[#171637356](https://www.pivotaltracker.com/story/show/171637356)

jobs/acceptance-tests-windows/templates/run.ps1

@@ -10,6 +10,7 @@ go.exe install bosh-dns/vendor/github.com/onsi/ginkgo/ginkgo
 
 Push-Location "${env:GOPATH}\src\bosh-dns\acceptance_tests\windows"
 
+$env:LOCAL_IP_ADDRESS = "<%= spec.ip %>"
 ginkgo -randomizeAllSpecs -randomizeSuites -race <%= p('suites') %>
 
 Pop-Location

jobs/bosh-dns-windows/monit

@@ -13,7 +13,7 @@ if p('override_nameserver')
     name: "bosh-dns-nameserverconfig-windows",
     executable: "/var/vcap/packages/bosh-dns-windows/bin/bosh-dns-nameserverconfig.exe",
 
-    args: ["--bindAddress", p('address') == "0.0.0.0" ? "127.0.0.1" : p('address')]
+    args: ["--bindAddress", p('address', spec.ip) == "0.0.0.0" ? "127.0.0.1" : p('address', spec.ip)]
   }
 end
 

jobs/bosh-dns-windows/spec

@@ -30,10 +30,8 @@ packages:
 properties:
   address:
     description: "Address in which the DNS server will bind"
-    default: 127.0.0.1
   aliased_address:
     description: "Address that will be added by default"
-    default: 127.0.0.1
   addresses_files_glob:
     description: "Glob for any files to look for extra addresses to listen on"
     default: C:\var\vcap\jobs\*\dns\addresses.json

jobs/bosh-dns-windows/templates/config.json.erb

@@ -1,6 +1,6 @@
 <%=
 {
-  address: p('address'),
+  address: p('address', spec.ip),
   port: p('port'),
   log_level: p('log_level'),
   recursors: p('recursors'),

src/bosh-dns/acceptance_tests/windows/windows_test.go

@@ -4,6 +4,7 @@ package windows_test
 
 import (
 	"fmt"
+	"os"
 	"os/exec"
 	"time"
 
@@ -14,6 +15,14 @@ import (
 )
 
 var _ = Describe("windows tests", func() {
+	var localIP string
+
+	BeforeEach(func() {
+		var present bool
+		localIP, present = os.LookupEnv("LOCAL_IP_ADDRESS")
+		Expect(present).To(BeTrue(), "LOCAL_IP_ADDRESS environment variable not set")
+		Expect(localIP).NotTo(BeEmpty(), "LOCAL_IP_ADDRESS environment variable not set")
+	})
 
 	It("should bind to tcp and udp", func() {
 		cmd := exec.Command("powershell.exe", "-Command", "netstat -na | findstr :53")
@@ -22,12 +31,12 @@ var _ = Describe("windows tests", func() {
 		Expect(err).NotTo(HaveOccurred())
 
 		Eventually(session, 10*time.Second).Should(gexec.Exit(0))
-		Expect(session.Out.Contents()).To(ContainSubstring(fmt.Sprintf("TCP    127.0.0.1:53")))
-		Expect(session.Out.Contents()).To(ContainSubstring(fmt.Sprintf("UDP    127.0.0.1:53")))
+		Expect(session.Out.Contents()).To(ContainSubstring(fmt.Sprintf("TCP    %s:53", localIP)))
+		Expect(session.Out.Contents()).To(ContainSubstring(fmt.Sprintf("UDP    %s:53", localIP)))
 	})
 
 	It("should respond to dns queries", func() {
-		cmd := exec.Command("powershell.exe", "-Command", fmt.Sprintf("Resolve-DnsName -DnsOnly -Name upcheck.bosh-dns. -Server 127.0.0.1 | Format-list"))
+		cmd := exec.Command("powershell.exe", "-Command", fmt.Sprintf("Resolve-DnsName -DnsOnly -Name upcheck.bosh-dns. -Server %s | Format-list", localIP))
 		session, err := gexec.Start(cmd, GinkgoWriter, GinkgoWriter)
 		Expect(err).NotTo(HaveOccurred())