Cors features improvements

docs/annotations.md

@@ -52,12 +52,20 @@ Key:
 | `base-url-scheme` | Specify the scheme of the `<base>` tags. | | nginx
 | `preserve-host` | Whether to pass the client request host (`true`) or the origin hostname (`false`) in the HTTP Host field. | | trafficserver
 
+## CORS Related
+| Name | Meaning | Default | Controller
+| --- | --- | --- | --- |
+| `enable-cors` | Enable CORS headers in response. | false | nginx, voyager
+| `cors-allow-origin` | Specifies the Origin allowed in CORS (Access-Control-Allow-Origin) | * | nginx
+| `cors-allow-headers` | Specifies the Headers allowed in CORS (Access-Control-Allow-Headers) | DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization | nginx
+| `cors-allow-methods` | Specifies the Methods allowed in CORS (Access-Control-Allow-Methods) | GET, PUT, POST, DELETE, PATCH, OPTIONS | nginx
+| `cors-allow-credentials` | Specifies the Access-Control-Allow-Credentials | true | nginx
+
 ## Miscellaneous
 
 | Name | Meaning | Default | Controller
 | --- | --- | --- | --- |
 | `configuration-snippet` | Arbitrary text to put in the generated configuration file. | | nginx
-| `enable-cors` | Enable CORS headers in response. | | nginx, voyager
 | `limit-connections` | Limit concurrent connections per IP address[1]. | | nginx, voyager
 | `limit-rps` | Limit requests per second per IP address[1]. | | nginx, voyager
 | `limit-rpm` | Limit requests per minute per IP address. | | nginx, voyager

docs/user-guide/annotations.md

@@ -20,6 +20,10 @@ The following annotations are supported:
 |[ingress.kubernetes.io/configuration-snippet](#configuration-snippet)|string|
 |[ingress.kubernetes.io/default-backend](#default-backend)|string|
 |[ingress.kubernetes.io/enable-cors](#enable-cors)|true or false|
+|[ingress.kubernetes.io/cors-allow-origin](#enable-cors)|string|
+|[ingress.kubernetes.io/cors-allow-methods](#enable-cors)|string|
+|[ingress.kubernetes.io/cors-allow-headers](#enable-cors)|string|
+|[ingress.kubernetes.io/cors-allow-credentials](#enable-cors)|true or false|
 |[ingress.kubernetes.io/force-ssl-redirect](#server-side-https-enforcement-through-redirect)|true or false|
 |[ingress.kubernetes.io/from-to-www-redirect](#redirect-from-to-www)|true or false|
 |[ingress.kubernetes.io/limit-connections](#rate-limiting)|number|
@@ -162,6 +166,26 @@ This is a global configuration for the ingress controller. In some cases could b
 ### Enable CORS
 
 To enable Cross-Origin Resource Sharing (CORS) in an Ingress rule add the annotation `ingress.kubernetes.io/enable-cors: "true"`. This will add a section in the server location enabling this functionality.
+
+CORS can be controlled with the following annotations:
+
+* `ingress.kubernetes.io/cors-allow-methods` controls which methods are accepted. This is a multi-valued field, separated by ',' and accepts only letters (upper and lower case).
+
+Example: `ingress.kubernetes.io/cors-allow-methods: "PUT, GET, POST, OPTIONS"`
+
+* `ingress.kubernetes.io/cors-allow-headers` controls which headers are accepted. This is a multi-valued field, separated by ',' and accepts letters, numbers, _ and -.
+
+Example: `ingress.kubernetes.io/cors-allow-methods: "X-Forwarded-For, X-app123-XPTO"`
+
+* `ingress.kubernetes.io/cors-allow-origin` controls what's the accepted Origin for CORS and defaults to '*'. This is a single field value, with the following format: http(s)://origin-site.com or http(s)://origin-site.com:port
+
+Example: `ingress.kubernetes.io/cors-allow-origin: "https://origin-site.com:4443"`
+
+* `ingress.kubernetes.io/cors-allow-credentials` controls if credentials can be passed during CORS operations.
+
+Example: `ingress.kubernetes.io/cors-allow-credentials: "true"`
+
+
 For more information please check https://enable-cors.org/server_nginx.html
 
 ### Server Alias

pkg/ingress/annotations/cors/main.go

@@ -17,25 +17,112 @@ limitations under the License.
 package cors
 
 import (
+	"regexp"
+
 	extensions "k8s.io/api/extensions/v1beta1"
 
 	"k8s.io/ingress-nginx/pkg/ingress/annotations/parser"
 )
 
 const (
-	annotation = "ingress.kubernetes.io/enable-cors"
+	annotationCorsEnabled          = "ingress.kubernetes.io/enable-cors"
+	annotationCorsAllowOrigin      = "ingress.kubernetes.io/cors-allow-origin"
+	annotationCorsAllowMethods     = "ingress.kubernetes.io/cors-allow-methods"
+	annotationCorsAllowHeaders     = "ingress.kubernetes.io/cors-allow-headers"
+	annotationCorsAllowCredentials = "ingress.kubernetes.io/cors-allow-credentials"
+	// Default values
+	defaultCorsMethods = "GET, PUT, POST, DELETE, PATCH, OPTIONS"
+	defaultCorsHeaders = "DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization"
+)
+
+var (
+	// Regex are defined here to prevent information leak, if user tries to set anything not valid
+	// that could cause the Response to contain some internal value/variable (like returning $pid, $upstream_addr, etc)
+	// Origin must contain a http/s Origin (including or not the port) or the value '*'
+	corsOriginRegex = regexp.MustCompile(`^(https?://[A-Za-z0-9\-\.]*(:[0-9]+)?|\*)?$`)
+	// 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?)+$`)
+	// Headers must contain valid values only (X-HEADER12, X-ABC)
+	// May contain or not spaces between each Header
+	corsHeadersRegex = regexp.MustCompile(`^([A-Za-z0-9\-\_]+,?\s?)+$`)
 )
 
 type cors struct {
 }
 
+// CorsConfig contains the Cors configuration to be used in the Ingress
+type CorsConfig struct {
+	CorsEnabled          bool   `json:"corsEnabled"`
+	CorsAllowOrigin      string `json:"corsAllowOrigin"`
+	CorsAllowMethods     string `json:"corsAllowMethods"`
+	CorsAllowHeaders     string `json:"corsAllowHeaders"`
+	CorsAllowCredentials bool   `json:"corsAllowCredentials"`
+}
+
 // NewParser creates a new CORS annotation parser
 func NewParser() parser.IngressAnnotation {
 	return cors{}
 }
 
+// Equal tests for equality between two External types
+func (c1 *CorsConfig) Equal(c2 *CorsConfig) bool {
+	if c1 == c2 {
+		return true
+	}
+	if c1 == nil || c2 == nil {
+		return false
+	}
+	if c1.CorsAllowCredentials != c2.CorsAllowCredentials {
+		return false
+	}
+	if c1.CorsAllowHeaders != c2.CorsAllowHeaders {
+		return false
+	}
+	if c1.CorsAllowOrigin != c2.CorsAllowOrigin {
+		return false
+	}
+	if c1.CorsEnabled != c2.CorsEnabled {
+		return false
+	}
+
+	return true
+}
+
 // Parse parses the annotations contained in the ingress
 // rule used to indicate if the location/s should allows CORS
 func (a cors) Parse(ing *extensions.Ingress) (interface{}, error) {
-	return parser.GetBoolAnnotation(annotation, ing)
+	corsenabled, err := parser.GetBoolAnnotation(annotationCorsEnabled, ing)
+	if err != nil {
+		corsenabled = false
+	}
+
+	corsalloworigin, err := parser.GetStringAnnotation(annotationCorsAllowOrigin, ing)
+	if err != nil || corsalloworigin == "" || !corsOriginRegex.MatchString(corsalloworigin) {
+		corsalloworigin = "*"
+	}
+
+	corsallowheaders, err := parser.GetStringAnnotation(annotationCorsAllowHeaders, ing)
+	if err != nil || corsallowheaders == "" || !corsHeadersRegex.MatchString(corsallowheaders) {
+		corsallowheaders = defaultCorsHeaders
+	}
+
+	corsallowmethods, err := parser.GetStringAnnotation(annotationCorsAllowMethods, ing)
+	if err != nil || corsallowmethods == "" || !corsMethodsRegex.MatchString(corsallowmethods) {
+		corsallowmethods = defaultCorsMethods
+	}
+
+	corsallowcredentials, err := parser.GetBoolAnnotation(annotationCorsAllowCredentials, ing)
+	if err != nil {
+		corsallowcredentials = true
+	}
+
+	return &CorsConfig{
+		CorsEnabled:          corsenabled,
+		CorsAllowOrigin:      corsalloworigin,
+		CorsAllowHeaders:     corsallowheaders,
+		CorsAllowMethods:     corsallowmethods,
+		CorsAllowCredentials: corsallowcredentials,
+	}, nil
+
 }

pkg/ingress/annotations/cors/main_test.go

@@ -22,42 +22,75 @@ import (
 	api "k8s.io/api/core/v1"
 	extensions "k8s.io/api/extensions/v1beta1"
 	meta_v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/intstr"
 )
 
-const (
-	notCorsAnnotation = "ingress.kubernetes.io/enable-not-cors"
-)
-
-func TestParse(t *testing.T) {
-	ap := NewParser()
-	if ap == nil {
-		t.Fatalf("expected a parser.IngressAnnotation but returned nil")
+func buildIngress() *extensions.Ingress {
+	defaultBackend := extensions.IngressBackend{
+		ServiceName: "default-backend",
+		ServicePort: intstr.FromInt(80),
 	}
 
-	testCases := []struct {
-		annotations map[string]string
-		expected    bool
-	}{
-		{map[string]string{annotation: "true"}, true},
-		{map[string]string{annotation: "false"}, false},
-		{map[string]string{notCorsAnnotation: "true"}, false},
-		{map[string]string{}, false},
-		{nil, false},
-	}
-
-	ing := &extensions.Ingress{
+	return &extensions.Ingress{
 		ObjectMeta: meta_v1.ObjectMeta{
 			Name:      "foo",
 			Namespace: api.NamespaceDefault,
 		},
-		Spec: extensions.IngressSpec{},
+		Spec: extensions.IngressSpec{
+			Backend: &extensions.IngressBackend{
+				ServiceName: "default-backend",
+				ServicePort: intstr.FromInt(80),
+			},
+			Rules: []extensions.IngressRule{
+				{
+					Host: "foo.bar.com",
+					IngressRuleValue: extensions.IngressRuleValue{
+						HTTP: &extensions.HTTPIngressRuleValue{
+							Paths: []extensions.HTTPIngressPath{
+								{
+									Path:    "/foo",
+									Backend: defaultBackend,
+								},
+							},
+						},
+					},
+				},
+			},
+		},
 	}
+}
+
+func TestIngressCorsConfig(t *testing.T) {
+	ing := buildIngress()
 
-	for _, testCase := range testCases {
-		ing.SetAnnotations(testCase.annotations)
-		result, _ := ap.Parse(ing)
-		if result != testCase.expected {
-			t.Errorf("expected %t but returned %t, annotations: %s", testCase.expected, result, testCase.annotations)
-		}
+	data := map[string]string{}
+	data[annotationCorsEnabled] = "true"
+	data[annotationCorsAllowHeaders] = "DNT,X-CustomHeader, Keep-Alive,User-Agent"
+	data[annotationCorsAllowCredentials] = "false"
+	data[annotationCorsAllowMethods] = "PUT, GET,OPTIONS, PATCH, $nginx_version"
+	data[annotationCorsAllowOrigin] = "https://origin123.test.com:4443"
+	ing.SetAnnotations(data)
+
+	corst, _ := NewParser().Parse(ing)
+	nginxCors, ok := corst.(*CorsConfig)
+	if !ok {
+		t.Errorf("expected a Config type")
 	}
+
+	if nginxCors.CorsEnabled != true {
+		t.Errorf("expected cors enabled but returned %v", nginxCors.CorsEnabled)
+	}
+
+	if nginxCors.CorsAllowHeaders != "DNT,X-CustomHeader, Keep-Alive,User-Agent" {
+		t.Errorf("expected headers not found. Found %v", nginxCors.CorsAllowHeaders)
+	}
+
+	if nginxCors.CorsAllowMethods != "GET, PUT, POST, DELETE, PATCH, OPTIONS" {
+		t.Errorf("expected default methods, but got  %v", nginxCors.CorsAllowMethods)
+	}
+
+	if nginxCors.CorsAllowOrigin != "https://origin123.test.com:4443" {
+		t.Errorf("expected origin https://origin123.test.com:4443, but got  %v", nginxCors.CorsAllowOrigin)
+	}
+
 }

pkg/ingress/controller/annotations.go

@@ -67,7 +67,7 @@ func newAnnotationExtractor(cfg extractorConfig) annotationExtractor {
 			"BasicDigestAuth":      auth.NewParser(auth.AuthDirectory, cfg),
 			"ExternalAuth":         authreq.NewParser(),
 			"CertificateAuth":      authtls.NewParser(cfg),
-			"EnableCORS":           cors.NewParser(),
+			"CorsConfig":           cors.NewParser(),
 			"HealthCheck":          healthcheck.NewParser(cfg),
 			"Whitelist":            ipwhitelist.NewParser(cfg),
 			"UsePortInRedirects":   portinredirect.NewParser(cfg),
@@ -130,6 +130,7 @@ const (
 	sessionAffinity      = "SessionAffinity"
 	serviceUpstream      = "ServiceUpstream"
 	serverAlias          = "Alias"
+	enableCors           = "EnableCORS"
 	clientBodyBufferSize = "ClientBodyBufferSize"
 	certificateAuth      = "CertificateAuth"
 	serverSnippet        = "ServerSnippet"
@@ -175,6 +176,11 @@ func (e *annotationExtractor) SessionAffinity(ing *extensions.Ingress) *sessiona
 	return val.(*sessionaffinity.AffinityConfig)
 }
 
+func (e *annotationExtractor) Cors(ing *extensions.Ingress) *cors.CorsConfig {
+	val, _ := e.annotations[enableCors].Parse(ing)
+	return val.(*cors.CorsConfig)
+}
+
 func (e *annotationExtractor) CertificateAuth(ing *extensions.Ingress) *authtls.AuthSSLConfig {
 	val, err := e.annotations[certificateAuth].Parse(ing)
 	if errors.IsMissingAnnotations(err) {

pkg/ingress/controller/annotations_test.go

@@ -29,15 +29,22 @@ import (
 )
 
 const (
-	annotationSecureUpstream     = "ingress.kubernetes.io/secure-backends"
-	annotationSecureVerifyCACert = "ingress.kubernetes.io/secure-verify-ca-secret"
-	annotationUpsMaxFails        = "ingress.kubernetes.io/upstream-max-fails"
-	annotationUpsFailTimeout     = "ingress.kubernetes.io/upstream-fail-timeout"
-	annotationPassthrough        = "ingress.kubernetes.io/ssl-passthrough"
-	annotationAffinityType       = "ingress.kubernetes.io/affinity"
-	annotationAffinityCookieName = "ingress.kubernetes.io/session-cookie-name"
-	annotationAffinityCookieHash = "ingress.kubernetes.io/session-cookie-hash"
-	annotationUpstreamHashBy     = "ingress.kubernetes.io/upstream-hash-by"
+	annotationSecureUpstream       = "ingress.kubernetes.io/secure-backends"
+	annotationSecureVerifyCACert   = "ingress.kubernetes.io/secure-verify-ca-secret"
+	annotationUpsMaxFails          = "ingress.kubernetes.io/upstream-max-fails"
+	annotationUpsFailTimeout       = "ingress.kubernetes.io/upstream-fail-timeout"
+	annotationPassthrough          = "ingress.kubernetes.io/ssl-passthrough"
+	annotationAffinityType         = "ingress.kubernetes.io/affinity"
+	annotationCorsEnabled          = "ingress.kubernetes.io/enable-cors"
+	annotationCorsAllowOrigin      = "ingress.kubernetes.io/cors-allow-origin"
+	annotationCorsAllowMethods     = "ingress.kubernetes.io/cors-allow-methods"
+	annotationCorsAllowHeaders     = "ingress.kubernetes.io/cors-allow-headers"
+	annotationCorsAllowCredentials = "ingress.kubernetes.io/cors-allow-credentials"
+	defaultCorsMethods             = "GET, PUT, POST, DELETE, PATCH, OPTIONS"
+	defaultCorsHeaders             = "DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Authorization"
+	annotationAffinityCookieName   = "ingress.kubernetes.io/session-cookie-name"
+	annotationAffinityCookieHash   = "ingress.kubernetes.io/session-cookie-hash"
+	annotationUpstreamHashBy       = "ingress.kubernetes.io/upstream-hash-by"
 )
 
 type mockCfg struct {
@@ -293,3 +300,54 @@ func TestAffinitySession(t *testing.T) {
 		}
 	}
 }
+
+func TestCors(t *testing.T) {
+	ec := newAnnotationExtractor(mockCfg{})
+	ing := buildIngress()
+
+	fooAnns := []struct {
+		annotations map[string]string
+		corsenabled bool
+		methods     string
+		headers     string
+		origin      string
+		credentials bool
+	}{
+		{map[string]string{annotationCorsEnabled: "true"}, true, defaultCorsMethods, defaultCorsHeaders, "*", true},
+		{map[string]string{annotationCorsEnabled: "true", annotationCorsAllowMethods: "POST, GET, OPTIONS", annotationCorsAllowHeaders: "$nginx_version", annotationCorsAllowCredentials: "false"}, true, "POST, GET, OPTIONS", defaultCorsHeaders, "*", false},
+		{map[string]string{annotationCorsEnabled: "true", annotationCorsAllowCredentials: "false"}, true, defaultCorsMethods, defaultCorsHeaders, "*", false},
+		{map[string]string{}, false, defaultCorsMethods, defaultCorsHeaders, "*", true},
+		{nil, false, defaultCorsMethods, defaultCorsHeaders, "*", true},
+	}
+
+	for _, foo := range fooAnns {
+		ing.SetAnnotations(foo.annotations)
+		r := ec.Cors(ing)
+		t.Logf("Testing pass %v %v %v %v %v", foo.corsenabled, foo.methods, foo.headers, foo.origin, foo.credentials)
+		if r == nil {
+			t.Errorf("Returned nil but expected a Cors.CorsConfig")
+			continue
+		}
+
+		if r.CorsEnabled != foo.corsenabled {
+			t.Errorf("Returned %v but expected %v for Cors Enabled", r.CorsEnabled, foo.corsenabled)
+		}
+
+		if r.CorsAllowHeaders != foo.headers {
+			t.Errorf("Returned %v but expected %v for Cors Headers", r.CorsAllowHeaders, foo.headers)
+		}
+
+		if r.CorsAllowMethods != foo.methods {
+			t.Errorf("Returned %v but expected %v for Cors Methods", r.CorsAllowMethods, foo.methods)
+		}
+
+		if r.CorsAllowOrigin != foo.origin {
+			t.Errorf("Returned %v but expected %v for Cors Methods", r.CorsAllowOrigin, foo.origin)
+		}
+
+		if r.CorsAllowCredentials != foo.credentials {
+			t.Errorf("Returned %v but expected %v for Cors Methods", r.CorsAllowCredentials, foo.credentials)
+		}
+
+	}
+}