Allow any protocol for cors origins (#11153)

Co-authored-by: Ricardo Katz <rikatz@users.noreply.github.com>

docs/user-guide/nginx-configuration/annotations.md

@@ -387,13 +387,13 @@ CORS can be controlled with the following annotations:
 
 * `nginx.ingress.kubernetes.io/cors-allow-origin`: Controls what's the accepted Origin for CORS.
 
-    This is a multi-valued field, separated by ','. It must follow this format: `http(s)://origin-site.com` or `http(s)://origin-site.com:port`
+    This is a multi-valued field, separated by ','. It must follow this format: `protocol://origin-site.com` or `protocol://origin-site.com:port`
 
     - Default: `*`
-    - Example: `nginx.ingress.kubernetes.io/cors-allow-origin: "https://origin-site.com:4443, http://origin-site.com, https://example.org:1199"`
+    - Example: `nginx.ingress.kubernetes.io/cors-allow-origin: "https://origin-site.com:4443, http://origin-site.com, myprotocol://example.org:1199"`
 
-    It also supports single level wildcard subdomains and follows this format: `http(s)://*.foo.bar`, `http(s)://*.bar.foo:8080` or `http(s)://*.abc.bar.foo:9000`
+    It also supports single level wildcard subdomains and follows this format: `protocol://*.foo.bar`, `protocol://*.bar.foo:8080` or `protocol://*.abc.bar.foo:9000`
-    - Example: `nginx.ingress.kubernetes.io/cors-allow-origin: "https://*.origin-site.com:4443, http://*.origin-site.com, https://example.org:1199"`
+    - Example: `nginx.ingress.kubernetes.io/cors-allow-origin: "https://*.origin-site.com:4443, http://*.origin-site.com, myprotocol://example.org:1199"`
 
 * `nginx.ingress.kubernetes.io/cors-allow-credentials`: Controls if credentials can be passed during CORS operations.
 

internal/ingress/annotations/cors/main.go

@@ -43,9 +43,9 @@ var (
 	// * Sets a group that can be (https?://)?*?.something.com:port?
 	// * Allows this to be repeated as much as possible, and separated by comma
 	// Otherwise it should be '*'
-	corsOriginRegexValidator = regexp.MustCompile(`^((((https?://)?(\*\.)?[A-Za-z0-9\-.]*(:\d+)?,?)+)|\*)?$`)
+	corsOriginRegexValidator = regexp.MustCompile(`^(((([a-z]+://)?(\*\.)?[A-Za-z0-9\-.]*(:\d+)?,?)+)|\*)?$`)
 	// corsOriginRegex defines the regex for validation inside Parse
-	corsOriginRegex = regexp.MustCompile(`^(https?://(\*\.)?[A-Za-z0-9\-.]*(:\d+)?|\*)?$`)
+	corsOriginRegex = regexp.MustCompile(`^([a-z]+://(\*\.)?[A-Za-z0-9\-.]*(:\d+)?|\*)?$`)
 	// Method must contain valid methods list (PUT, GET, POST, BLA)
 	// May contain or not spaces between each verb
 	corsMethodsRegex = regexp.MustCompile(`^([A-Za-z]+,?\s?)+$`)
@@ -78,8 +78,9 @@ var corsAnnotation = parser.Annotation{
 			Scope:     parser.AnnotationScopeIngress,
 			Risk:      parser.AnnotationRiskMedium,
 			Documentation: `This annotation controls what's the accepted Origin for CORS.
-			This is a multi-valued field, separated by ','. It must follow this format: http(s)://origin-site.com or http(s)://origin-site.com:port
+			This is a multi-valued field, separated by ','. It must follow this format: protocol://origin-site.com or protocol://origin-site.com:port
-			It also supports single level wildcard subdomains and follows this format: http(s)://*.foo.bar, http(s)://*.bar.foo:8080 or http(s)://*.abc.bar.foo:9000`,
+			It also supports single level wildcard subdomains and follows this format: https://*.foo.bar, http://*.bar.foo:8080 or myprotocol://*.abc.bar.foo:9000
+			Protocol can be any lowercase string, like http, https, or mycustomprotocol.`,
 		},
 		corsAllowHeadersAnnotation: {
 			Validator: parser.ValidateRegex(parser.HeadersVariable, true),

internal/ingress/annotations/cors/main_test.go

@@ -27,6 +27,8 @@ import (
 	"k8s.io/ingress-nginx/internal/ingress/resolver"
 )
 
+const enableAnnotation = "true"
+
 func buildIngress() *networking.Ingress {
 	defaultBackend := networking.IngressBackend{
 		Service: &networking.IngressServiceBackend{
@@ -76,7 +78,7 @@ func TestIngressCorsConfigValid(t *testing.T) {
 	data := map[string]string{}
 
 	// Valid
-	data[parser.GetAnnotationWithPrefix(corsEnableAnnotation)] = "true"
+	data[parser.GetAnnotationWithPrefix(corsEnableAnnotation)] = enableAnnotation
 	data[parser.GetAnnotationWithPrefix(corsAllowHeadersAnnotation)] = "DNT,X-CustomHeader, Keep-Alive,User-Agent"
 	data[parser.GetAnnotationWithPrefix(corsAllowCredentialsAnnotation)] = "false"
 	data[parser.GetAnnotationWithPrefix(corsAllowMethodsAnnotation)] = "GET, PATCH"
@@ -178,7 +180,7 @@ func TestIngresCorsConfigAllowOriginWithTrailingComma(t *testing.T) {
 	ing := buildIngress()
 
 	data := map[string]string{}
-	data[parser.GetAnnotationWithPrefix(corsEnableAnnotation)] = "true"
+	data[parser.GetAnnotationWithPrefix(corsEnableAnnotation)] = enableAnnotation
 
 	// Include a trailing comma and an empty value between the commas.
 	data[parser.GetAnnotationWithPrefix(corsAllowOriginAnnotation)] = "https://origin123.test.com:4443,    ,https://origin321.test.com:4443,"
@@ -203,3 +205,33 @@ func TestIngresCorsConfigAllowOriginWithTrailingComma(t *testing.T) {
 		t.Errorf("expected %v but returned %v", expectedCorsAllowOrigins, nginxCors.CorsAllowOrigin)
 	}
 }
+
+func TestIngressCorsConfigAllowOriginWithNonHttpProtocol(t *testing.T) {
+	ing := buildIngress()
+
+	data := map[string]string{}
+	data[parser.GetAnnotationWithPrefix(corsEnableAnnotation)] = enableAnnotation
+
+	// Include a trailing comma and an empty value between the commas.
+	data[parser.GetAnnotationWithPrefix(corsAllowOriginAnnotation)] = "test://localhost"
+	ing.SetAnnotations(data)
+
+	corst, err := NewParser(&resolver.Mock{}).Parse(ing)
+	if err != nil {
+		t.Errorf("error parsing annotations: %v", err)
+	}
+
+	nginxCors, ok := corst.(*Config)
+	if !ok {
+		t.Errorf("expected a Config type but returned %t", corst)
+	}
+
+	if !nginxCors.CorsEnabled {
+		t.Errorf("expected %v but returned %v", data[parser.GetAnnotationWithPrefix(corsEnableAnnotation)], nginxCors.CorsEnabled)
+	}
+
+	expectedCorsAllowOrigins := []string{"test://localhost"}
+	if !reflect.DeepEqual(nginxCors.CorsAllowOrigin, expectedCorsAllowOrigins) {
+		t.Errorf("expected %v but returned %v", expectedCorsAllowOrigins, nginxCors.CorsAllowOrigin)
+	}
+}

test/e2e/annotations/cors.go

@@ -669,4 +669,33 @@ var _ = framework.DescribeAnnotation("cors-*", func() {
 			Headers().
 			NotContainsKey("Access-Control-Allow-Origin")
 	})
+
+	ginkgo.It("should allow - origins with non-http[s] protocols", func() {
+		host := corsHost
+		origin := "test://localhost"
+		origin2 := "tauri://localhost:3000"
+		annotations := map[string]string{
+			"nginx.ingress.kubernetes.io/enable-cors":       "true",
+			"nginx.ingress.kubernetes.io/cors-allow-origin": "test://localhost, tauri://localhost:3000",
+		}
+
+		ing := framework.NewSingleIngress(host, "/", host, f.Namespace, framework.EchoService, 80, annotations)
+		f.EnsureIngress(ing)
+
+		f.HTTPTestClient().
+			GET("/").
+			WithHeader("Host", host).
+			WithHeader("Origin", origin).
+			Expect().
+			Status(http.StatusOK).Headers().
+			ValueEqual("Access-Control-Allow-Origin", []string{"test://localhost"})
+
+		f.HTTPTestClient().
+			GET("/").
+			WithHeader("Host", host).
+			WithHeader("Origin", origin2).
+			Expect().
+			Status(http.StatusOK).Headers().
+			ValueEqual("Access-Control-Allow-Origin", []string{"tauri://localhost:3000"})
+	})
 })