feat: dialer refactor to support modular dialing/checking/proxying

This commit is contained in:
James Houlahan
2020-04-23 14:41:59 +02:00
committed by Michal Horejsek
parent 8c2f88fe70
commit 0fd5ca3a24
12 changed files with 651 additions and 449 deletions

View File

@ -18,6 +18,7 @@
package pmapi
import (
"crypto/tls"
"net/http"
"net/http/httptest"
"testing"
@ -32,12 +33,114 @@ const (
TestGoogleProvider = "https://dns.google/dns-query"
)
// getTrustedServer returns a server and sets its public key as one of the pinned ones.
func getTrustedServer() *httptest.Server {
proxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
pin := certFingerprint(proxy.Certificate())
TrustedAPIPins = append(TrustedAPIPins, pin)
return proxy
}
// server.crt
const servercrt = `
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
`
const serverkey = `
-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----
`
// getUntrustedServer returns a server but it doesn't add its public key to the list of pinned ones.
func getUntrustedServer() *httptest.Server {
server := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
cert, err := tls.X509KeyPair([]byte(servercrt), []byte(serverkey))
if err != nil {
panic(err)
}
server.TLS = &tls.Config{Certificates: []tls.Certificate{cert}}
server.StartTLS()
return server
}
// closeServer closes the given server. If it is a trusted server, its cert is removed from the trusted public keys.
func closeServer(server *httptest.Server) {
pin := certFingerprint(server.Certificate())
for i := range TrustedAPIPins {
if TrustedAPIPins[i] == pin {
TrustedAPIPins = append(TrustedAPIPins[:i], TrustedAPIPins[i:]...)
break
}
}
server.Close()
}
func TestProxyProvider_FindProxy(t *testing.T) {
blockAPI()
defer unblockAPI()
proxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy.Close()
proxy := getTrustedServer()
defer closeServer(proxy)
p := newProxyProvider([]string{"not used"}, "not used")
p.dohLookup = func(q, p string) ([]string, error) { return []string{proxy.URL}, nil }
@ -51,34 +154,72 @@ func TestProxyProvider_FindProxy_ChooseReachableProxy(t *testing.T) {
blockAPI()
defer unblockAPI()
badProxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
goodProxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
reachableProxy := getTrustedServer()
defer closeServer(reachableProxy)
// Close the bad proxy first so it isn't reachable; we should then choose the good proxy.
badProxy.Close()
defer goodProxy.Close()
// We actually close the unreachable proxy straight away rather than deferring the closure.
unreachableProxy := getTrustedServer()
closeServer(unreachableProxy)
p := newProxyProvider([]string{"not used"}, "not used")
p.dohLookup = func(q, p string) ([]string, error) { return []string{badProxy.URL, goodProxy.URL}, nil }
p.dohLookup = func(q, p string) ([]string, error) { return []string{reachableProxy.URL, unreachableProxy.URL}, nil }
url, err := p.findReachableServer()
require.NoError(t, err)
require.Equal(t, goodProxy.URL, url)
require.Equal(t, reachableProxy.URL, url)
}
func TestProxyProvider_FindProxy_ChooseTrustedProxy(t *testing.T) {
blockAPI()
defer unblockAPI()
trustedProxy := getTrustedServer()
defer closeServer(trustedProxy)
untrustedProxy := getUntrustedServer()
defer closeServer(untrustedProxy)
p := newProxyProvider([]string{"not used"}, "not used")
p.dohLookup = func(q, p string) ([]string, error) { return []string{untrustedProxy.URL, trustedProxy.URL}, nil }
url, err := p.findReachableServer()
require.NoError(t, err)
require.Equal(t, trustedProxy.URL, url)
}
func TestProxyProvider_FindProxy_FailIfNoneReachable(t *testing.T) {
blockAPI()
defer unblockAPI()
badProxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
anotherBadProxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
unreachableProxy1 := getTrustedServer()
closeServer(unreachableProxy1)
// Close the proxies to simulate them not being reachable.
badProxy.Close()
anotherBadProxy.Close()
unreachableProxy2 := getTrustedServer()
closeServer(unreachableProxy2)
p := newProxyProvider([]string{"not used"}, "not used")
p.dohLookup = func(q, p string) ([]string, error) { return []string{badProxy.URL, anotherBadProxy.URL}, nil }
p.dohLookup = func(q, p string) ([]string, error) {
return []string{unreachableProxy1.URL, unreachableProxy2.URL}, nil
}
_, err := p.findReachableServer()
require.Error(t, err)
}
func TestProxyProvider_FindProxy_FailIfNoneTrusted(t *testing.T) {
blockAPI()
defer unblockAPI()
untrustedProxy1 := getUntrustedServer()
defer closeServer(untrustedProxy1)
untrustedProxy2 := getUntrustedServer()
defer closeServer(untrustedProxy2)
p := newProxyProvider([]string{"not used"}, "not used")
p.dohLookup = func(q, p string) ([]string, error) {
return []string{untrustedProxy1.URL, untrustedProxy2.URL}, nil
}
_, err := p.findReachableServer()
require.Error(t, err)
@ -88,9 +229,6 @@ func TestProxyProvider_FindProxy_LookupTimeout(t *testing.T) {
blockAPI()
defer unblockAPI()
proxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy.Close()
p := newProxyProvider([]string{"not used"}, "not used")
p.lookupTimeout = time.Second
p.dohLookup = func(q, p string) ([]string, error) { time.Sleep(2 * time.Second); return nil, nil }
@ -124,17 +262,17 @@ func TestProxyProvider_UseProxy(t *testing.T) {
cm := newTestClientManager(testClientConfig)
proxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy.Close()
trustedProxy := getTrustedServer()
defer closeServer(trustedProxy)
p := newProxyProvider([]string{"not used"}, "not used")
cm.proxyProvider = p
p.dohLookup = func(q, p string) ([]string, error) { return []string{proxy.URL}, nil }
p.dohLookup = func(q, p string) ([]string, error) { return []string{trustedProxy.URL}, nil }
url, err := cm.switchToReachableServer()
require.NoError(t, err)
require.Equal(t, proxy.URL, url)
require.Equal(t, proxy.URL, cm.getHost())
require.Equal(t, trustedProxy.URL, url)
require.Equal(t, trustedProxy.URL, cm.getHost())
}
func TestProxyProvider_UseProxy_MultipleTimes(t *testing.T) {
@ -143,12 +281,12 @@ func TestProxyProvider_UseProxy_MultipleTimes(t *testing.T) {
cm := newTestClientManager(testClientConfig)
proxy1 := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy1.Close()
proxy2 := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy2.Close()
proxy3 := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy3.Close()
proxy1 := getTrustedServer()
defer closeServer(proxy1)
proxy2 := getTrustedServer()
defer closeServer(proxy2)
proxy3 := getTrustedServer()
defer closeServer(proxy3)
p := newProxyProvider([]string{"not used"}, "not used")
cm.proxyProvider = p
@ -184,18 +322,18 @@ func TestProxyProvider_UseProxy_RevertAfterTime(t *testing.T) {
cm := newTestClientManager(testClientConfig)
proxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy.Close()
trustedProxy := getTrustedServer()
defer closeServer(trustedProxy)
p := newProxyProvider([]string{"not used"}, "not used")
cm.proxyProvider = p
cm.proxyUseDuration = time.Second
p.dohLookup = func(q, p string) ([]string, error) { return []string{proxy.URL}, nil }
p.dohLookup = func(q, p string) ([]string, error) { return []string{trustedProxy.URL}, nil }
url, err := cm.switchToReachableServer()
require.NoError(t, err)
require.Equal(t, proxy.URL, url)
require.Equal(t, proxy.URL, cm.getHost())
require.Equal(t, trustedProxy.URL, url)
require.Equal(t, trustedProxy.URL, cm.getHost())
time.Sleep(2 * time.Second)
require.Equal(t, rootURL, cm.getHost())
@ -207,26 +345,27 @@ func TestProxyProvider_UseProxy_RevertIfProxyStopsWorkingAndOriginalAPIIsReachab
cm := newTestClientManager(testClientConfig)
proxy := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy.Close()
trustedProxy := getTrustedServer()
p := newProxyProvider([]string{"not used"}, "not used")
cm.proxyProvider = p
p.dohLookup = func(q, p string) ([]string, error) { return []string{proxy.URL}, nil }
p.dohLookup = func(q, p string) ([]string, error) { return []string{trustedProxy.URL}, nil }
url, err := cm.switchToReachableServer()
require.NoError(t, err)
require.Equal(t, proxy.URL, url)
require.Equal(t, proxy.URL, cm.getHost())
require.Equal(t, trustedProxy.URL, url)
require.Equal(t, trustedProxy.URL, cm.getHost())
// Simulate that the proxy stops working and that the standard api is reachable again.
proxy.Close()
closeServer(trustedProxy)
unblockAPI()
time.Sleep(proxyLookupWait)
// We should now find the original API URL if it is working again.
// The error should be ErrAPINotReachable because the connection dropped intermittently but
// the original API is now reachable (see Alternative-Routing-v2 spec for details).
url, err = cm.switchToReachableServer()
require.NoError(t, err)
require.EqualError(t, err, ErrAPINotReachable.Error())
require.Equal(t, rootURL, url)
require.Equal(t, rootURL, cm.getHost())
}
@ -237,10 +376,11 @@ func TestProxyProvider_UseProxy_FindSecondAlternativeIfFirstFailsAndAPIIsStillBl
cm := newTestClientManager(testClientConfig)
proxy1 := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy1.Close()
proxy2 := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
defer proxy2.Close()
// proxy1 is closed later in this test so we don't defer it here.
proxy1 := getTrustedServer()
proxy2 := getTrustedServer()
defer closeServer(proxy2)
p := newProxyProvider([]string{"not used"}, "not used")
cm.proxyProvider = p