Bump version to 2.2.11

* add tests to demonstrate issue

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

more

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

docs

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

settings tests

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

tests for OIDC handlers, consolidating test helpers

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

consolidate

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

consolidate

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

docs

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

* fix log message

Signed-off-by: Michael Crenshaw <michael@crenshaw.dev>

VERSION

@@ -1 +1 @@
-2.2.10
+2.2.11

docs/operator-manual/argocd-cm.yaml

@@ -242,3 +242,9 @@ data:
   # published to the repository. Reconciliation by timeout is disabled if timeout is set to 0. Three minutes by default.
   # > Note: argocd-repo-server deployment must be manually restarted after changing the setting.
   timeout.reconciliation: 180s
+
+  # oidc.tls.insecure.skip.verify determines whether certificate verification is skipped when verifying tokens with the
+  # configured OIDC provider (either external or the bundled Dex instance). Setting this to "true" will cause JWT
+  # token verification to pass despite the OIDC provider having an invalid certificate. Only set to "true" if you
+  # understand the risks.
+  oidc.tls.insecure.skip.verify: "false"

docs/operator-manual/user-management/index.md

@@ -373,6 +373,21 @@ You are not required to specify a logoutRedirectURL as this is automatically gen
 !!! note
    The post logout redirect URI may need to be whitelisted against your OIDC provider's client settings for ArgoCD.
 
+### Configuring a custom root CA certificate for communicating with the OIDC provider
+
+If your OIDC provider is setup with a certificate which is not signed by one of the well known certificate authorities
+you can provide a custom certificate which will be used in verifying the OIDC provider's TLS certificate when
+communicating with it.  
+Add a `rootCA` to your `oidc.config` which contains the PEM encoded root certificate:
+
+```yaml
+  oidc.config: |
+    ...
+    rootCA: |
+      -----BEGIN CERTIFICATE-----
+      ... encoded certificate data here ...
+      -----END CERTIFICATE-----
+```
 
 
 ## SSO Further Reading
@@ -477,3 +492,20 @@ data:
     clientSecret: $another-secret:oidc.auth0.clientSecret  # Mind the ':'
   ...
 ```
+
+### Skipping certificate verification on OIDC provider connections
+
+By default, all connections made by the API server to OIDC providers (either external providers or the bundled Dex
+instance) must pass certificate validation. These connections occur when getting the OIDC provider's well-known
+configuration, when getting the OIDC provider's keys, and  when exchanging an authorization code or verifying an ID 
+token as part of an OIDC login flow.
+
+Disabling certificate verification might make sense if:
+* You are using the bundled Dex instance **and** your Argo CD instance has TLS configured with a self-signed certificate
+  **and** you understand and accept the risks of skipping OIDC provider cert verification.
+* You are using an external OIDC provider **and** that provider uses an invalid certificate **and** you cannot solve
+  the problem by setting `oidcConfig.rootCA` **and** you understand and accept the risks of skipping OIDC provider cert 
+  verification.
+
+If either of those two applies, then you can disable OIDC provider certificate verification by setting
+`oidc.tls.insecure.skip.verify` to `"true"` in the `argocd-cm` ConfigMap.

manifests/base/kustomization.yaml

@@ -5,7 +5,7 @@ kind: Kustomization
 images:
 - name: quay.io/argoproj/argocd
   newName: quay.io/argoproj/argocd
-  newTag: v2.2.10
+  newTag: v2.2.11
 resources:
 - ./application-controller
 - ./dex

manifests/core-install.yaml

@@ -3024,7 +3024,7 @@ spec:
           value: /helm-working-dir
         - name: HELM_DATA_HOME
           value: /helm-working-dir
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           failureThreshold: 3
@@ -3073,7 +3073,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /var/run/argocd/argocd-cmp-server
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         name: copyutil
         volumeMounts:
         - mountPath: /var/run/argocd
@@ -3238,7 +3238,7 @@ spec:
               key: controller.default.cache.expiration
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:

manifests/core-install/kustomization.yaml

@@ -11,4 +11,4 @@ resources:
 images:
 - name: quay.io/argoproj/argocd
   newName: quay.io/argoproj/argocd
-  newTag: v2.2.10
+  newTag: v2.2.11

manifests/ha/base/kustomization.yaml

@@ -11,7 +11,7 @@ patchesStrategicMerge:
 images:
 - name: quay.io/argoproj/argocd
   newName: quay.io/argoproj/argocd
-  newTag: v2.2.10
+  newTag: v2.2.11
 resources:
 - ../../base/application-controller
 - ../../base/dex

manifests/ha/install.yaml

@@ -3709,7 +3709,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /shared/argocd-dex
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         name: copyutil
         volumeMounts:
@@ -3932,7 +3932,7 @@ spec:
           value: /helm-working-dir
         - name: HELM_DATA_HOME
           value: /helm-working-dir
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           failureThreshold: 3
@@ -3981,7 +3981,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /var/run/argocd/argocd-cmp-server
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         name: copyutil
         volumeMounts:
         - mountPath: /var/run/argocd
@@ -4208,7 +4208,7 @@ spec:
               key: server.http.cookie.maxnumber
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:
@@ -4404,7 +4404,7 @@ spec:
               key: controller.default.cache.expiration
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:

manifests/ha/namespace-install.yaml

@@ -1068,7 +1068,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /shared/argocd-dex
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         name: copyutil
         volumeMounts:
@@ -1291,7 +1291,7 @@ spec:
           value: /helm-working-dir
         - name: HELM_DATA_HOME
           value: /helm-working-dir
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           failureThreshold: 3
@@ -1340,7 +1340,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /var/run/argocd/argocd-cmp-server
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         name: copyutil
         volumeMounts:
         - mountPath: /var/run/argocd
@@ -1567,7 +1567,7 @@ spec:
               key: server.http.cookie.maxnumber
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:
@@ -1763,7 +1763,7 @@ spec:
               key: controller.default.cache.expiration
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:

manifests/install.yaml

@@ -3079,7 +3079,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /shared/argocd-dex
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         name: copyutil
         volumeMounts:
@@ -3266,7 +3266,7 @@ spec:
           value: /helm-working-dir
         - name: HELM_DATA_HOME
           value: /helm-working-dir
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           failureThreshold: 3
@@ -3315,7 +3315,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /var/run/argocd/argocd-cmp-server
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         name: copyutil
         volumeMounts:
         - mountPath: /var/run/argocd
@@ -3538,7 +3538,7 @@ spec:
               key: server.http.cookie.maxnumber
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:
@@ -3728,7 +3728,7 @@ spec:
               key: controller.default.cache.expiration
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:

manifests/namespace-install.yaml

@@ -438,7 +438,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /shared/argocd-dex
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         name: copyutil
         volumeMounts:
@@ -625,7 +625,7 @@ spec:
           value: /helm-working-dir
         - name: HELM_DATA_HOME
           value: /helm-working-dir
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           failureThreshold: 3
@@ -674,7 +674,7 @@ spec:
         - -n
         - /usr/local/bin/argocd
         - /var/run/argocd/argocd-cmp-server
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         name: copyutil
         volumeMounts:
         - mountPath: /var/run/argocd
@@ -897,7 +897,7 @@ spec:
               key: server.http.cookie.maxnumber
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:
@@ -1087,7 +1087,7 @@ spec:
               key: controller.default.cache.expiration
               name: argocd-cmd-params-cm
               optional: true
-        image: quay.io/argoproj/argocd:v2.2.10
+        image: quay.io/argoproj/argocd:v2.2.11
         imagePullPolicy: Always
         livenessProbe:
           httpGet:

util/oidc/oidc.go

@@ -107,10 +107,7 @@ func NewClientApp(settings *settings.ArgoCDSettings, cache OIDCStateStorage, dex
 	if err != nil {
 		return nil, fmt.Errorf("parse redirect-uri: %v", err)
 	}
-	tlsConfig := settings.TLSConfig()
-	if tlsConfig != nil {
-		tlsConfig.InsecureSkipVerify = true
-	}
+	tlsConfig := settings.OIDCTLSConfig()
 	a.client = &http.Client{
 		Transport: &http.Transport{
 			TLSClientConfig: tlsConfig,

util/oidc/oidc_test.go

@@ -1,7 +1,9 @@
 package oidc
 
 import (
+	"crypto/tls"
 	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"net/http/httptest"
 	"net/url"
@@ -9,9 +11,12 @@ import (
 
 	gooidc "github.com/coreos/go-oidc"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"golang.org/x/oauth2"
 
 	"github.com/argoproj/argo-cd/v2/server/settings/oidc"
+	"github.com/argoproj/argo-cd/v2/util/settings"
+	"github.com/argoproj/argo-cd/v2/util/test"
 )
 
 func TestInferGrantType(t *testing.T) {
@@ -97,6 +102,176 @@ func TestHandleCallback(t *testing.T) {
 	assert.Equal(t, "login-failed: <script>alert('hello')</script>\n", w.Body.String())
 }
 
+type mockOIDCStateStorage struct {}
+
+func (m mockOIDCStateStorage) GetOIDCState(key string) (*OIDCState, error) {
+	return nil, nil
+}
+
+func (m mockOIDCStateStorage) SetOIDCState(key string, state *OIDCState) error {
+	return nil
+}
+
+func getTestCache() OIDCStateStorage {
+	return mockOIDCStateStorage{}
+}
+
+func TestClientApp_HandleLogin(t *testing.T) {
+	oidcTestServer := test.GetOIDCTestServer(t)
+	t.Cleanup(oidcTestServer.Close)
+
+	dexTestServer := test.GetDexTestServer(t)
+	t.Cleanup(dexTestServer.Close)
+
+	t.Run("oidc certificate checking during login should toggle on config", func(t *testing.T) {
+		cdSettings := &settings.ArgoCDSettings{
+			URL: "https://argocd.example.com",
+			OIDCConfigRAW: fmt.Sprintf(`
+name: Test
+issuer: %s
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]`, oidcTestServer.URL),
+		}
+		app, err := NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		req := httptest.NewRequest("GET", "https://argocd.example.com/auth/login", nil)
+
+		w := httptest.NewRecorder()
+
+		app.HandleLogin(w, req)
+
+		assert.Contains(t, w.Body.String(), "certificate is not trusted")
+
+		cdSettings.OIDCTLSInsecureSkipVerify = true
+
+		app, err = NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		w = httptest.NewRecorder()
+
+		app.HandleLogin(w, req)
+
+		assert.NotContains(t, w.Body.String(), "certificate is not trusted")
+	})
+
+	t.Run("dex certificate checking during login should toggle on config", func(t *testing.T) {
+		cdSettings := &settings.ArgoCDSettings{
+			URL: "https://argocd.example.com",
+			DexConfig: `connectors:
+- type: github
+  name: GitHub
+  config:
+    clientID: aabbccddeeff00112233
+    clientSecret: aabbccddeeff00112233`,
+		}
+		cert, err := tls.X509KeyPair(test.Cert, test.PrivateKey)
+		require.NoError(t, err)
+		cdSettings.Certificate = &cert
+
+		app, err := NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		req := httptest.NewRequest("GET", "https://argocd.example.com/auth/login", nil)
+
+		w := httptest.NewRecorder()
+
+		app.HandleLogin(w, req)
+
+		assert.Contains(t, w.Body.String(), "certificate signed by unknown authority")
+
+		cdSettings.OIDCTLSInsecureSkipVerify = true
+
+		app, err = NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		w = httptest.NewRecorder()
+
+		app.HandleLogin(w, req)
+
+		assert.NotContains(t, w.Body.String(), "certificate signed by unknown authority")
+	})
+}
+
+func TestClientApp_HandleCallback(t *testing.T) {
+	oidcTestServer := test.GetOIDCTestServer(t)
+	t.Cleanup(oidcTestServer.Close)
+
+	dexTestServer := test.GetDexTestServer(t)
+	t.Cleanup(dexTestServer.Close)
+
+	t.Run("oidc certificate checking during oidc callback should toggle on config", func(t *testing.T) {
+		cdSettings := &settings.ArgoCDSettings{
+			URL: "https://argocd.example.com",
+			OIDCConfigRAW: fmt.Sprintf(`
+name: Test
+issuer: %s
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]`, oidcTestServer.URL),
+		}
+		app, err := NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		req := httptest.NewRequest("GET", "https://argocd.example.com/auth/callback", nil)
+
+		w := httptest.NewRecorder()
+
+		app.HandleCallback(w, req)
+
+		assert.Contains(t, w.Body.String(), "certificate is not trusted")
+
+		cdSettings.OIDCTLSInsecureSkipVerify = true
+
+		app, err = NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		w = httptest.NewRecorder()
+
+		app.HandleCallback(w, req)
+
+		assert.NotContains(t, w.Body.String(), "certificate is not trusted")
+	})
+
+	t.Run("dex certificate checking during oidc callback should toggle on config", func(t *testing.T) {
+		cdSettings := &settings.ArgoCDSettings{
+			URL: "https://argocd.example.com",
+			DexConfig: `connectors:
+- type: github
+  name: GitHub
+  config:
+    clientID: aabbccddeeff00112233
+    clientSecret: aabbccddeeff00112233`,
+		}
+		cert, err := tls.X509KeyPair(test.Cert, test.PrivateKey)
+		require.NoError(t, err)
+		cdSettings.Certificate = &cert
+
+		app, err := NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		req := httptest.NewRequest("GET", "https://argocd.example.com/auth/callback", nil)
+
+		w := httptest.NewRecorder()
+
+		app.HandleCallback(w, req)
+
+		assert.Contains(t, w.Body.String(), "certificate signed by unknown authority")
+
+		cdSettings.OIDCTLSInsecureSkipVerify = true
+
+		app, err = NewClientApp(cdSettings, getTestCache(), dexTestServer.URL, "https://argocd.example.com")
+		require.NoError(t, err)
+
+		w = httptest.NewRecorder()
+
+		app.HandleCallback(w, req)
+
+		assert.NotContains(t, w.Body.String(), "certificate signed by unknown authority")
+	})
+}
+
 func TestIsValidRedirect(t *testing.T) {
 	var tests = []struct {
 		name        string

util/session/sessionmanager.go

@@ -124,10 +124,7 @@ func NewSessionManager(settingsMgr *settings.SettingsManager, projectsLister v1a
 	if err != nil {
 		panic(err)
 	}
-	tlsConfig := settings.TLSConfig()
-	if tlsConfig != nil {
-		tlsConfig.InsecureSkipVerify = true
-	}
+	tlsConfig := settings.OIDCTLSConfig()
 	s.client = &http.Client{
 		Transport: &http.Transport{
 			TLSClientConfig: tlsConfig,

util/session/sessionmanager_test.go

@@ -2,6 +2,7 @@ package session
 
 import (
 	"context"
+	"encoding/pem"
 	"fmt"
 	"math"
 	"os"
@@ -28,6 +29,7 @@ import (
 	"github.com/argoproj/argo-cd/v2/util/errors"
 	"github.com/argoproj/argo-cd/v2/util/password"
 	"github.com/argoproj/argo-cd/v2/util/settings"
+	utiltest "github.com/argoproj/argo-cd/v2/util/test"
 )
 
 func getProjLister(objects ...runtime.Object) v1alpha1.AppProjectNamespaceLister {
@@ -456,3 +458,239 @@ func TestFailedAttemptsExpiry(t *testing.T) {
 
 	os.Setenv(envLoginFailureWindowSeconds, "")
 }
+
+func getKubeClientWithConfig(config map[string]string, secretConfig map[string][]byte) *fake.Clientset {
+	mergedSecretConfig := map[string][]byte{
+		"server.secretkey": []byte("Hello, world!"),
+	}
+	for key, value := range secretConfig {
+		mergedSecretConfig[key] = value
+	}
+
+	return fake.NewSimpleClientset(&corev1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "argocd-cm",
+			Namespace: "argocd",
+			Labels: map[string]string{
+				"app.kubernetes.io/part-of": "argocd",
+			},
+		},
+		Data: config,
+	}, &corev1.Secret{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "argocd-secret",
+			Namespace: "argocd",
+		},
+		Data: mergedSecretConfig,
+	})
+}
+
+func TestSessionManager_VerifyToken(t *testing.T) {
+	oidcTestServer := utiltest.GetOIDCTestServer(t)
+	t.Cleanup(oidcTestServer.Close)
+
+	dexTestServer := utiltest.GetDexTestServer(t)
+	t.Cleanup(dexTestServer.Close)
+
+	t.Run("oidcConfig.rootCA is respected", func(t *testing.T) {
+		cert := pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: oidcTestServer.TLS.Certificates[0].Certificate[0]})
+
+		dexConfig := map[string]string{
+			"url": "",
+			"oidc.config": fmt.Sprintf(`
+name: Test
+issuer: %s
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]
+rootCA: |
+  %s
+`, oidcTestServer.URL, strings.Replace(string(cert), "\n", "\n  ", -1)),
+		}
+
+		settingsMgr := settings.NewSettingsManager(context.Background(), getKubeClientWithConfig(dexConfig, nil), "argocd")
+		mgr := NewSessionManager(settingsMgr, getProjLister(), "", NewUserStateStorage(nil))
+		mgr.verificationDelayNoiseEnabled = false
+
+		claims := jwt.StandardClaims{Audience: jwt.ClaimStrings{"test-client"}, Subject: "admin", ExpiresAt: jwt.At(time.Now().Add(time.Hour * 24))}
+		claims.Issuer = oidcTestServer.URL
+		token := jwt.NewWithClaims(jwt.SigningMethodRS256, claims)
+		key, err := jwt.ParseRSAPrivateKeyFromPEM(utiltest.PrivateKey)
+		require.NoError(t, err)
+		tokenString, err := token.SignedString(key)
+		require.NoError(t, err)
+
+		_, _, err = mgr.VerifyToken(tokenString)
+		// If the root CA is being respected, we won't get this error.
+		assert.NotContains(t, err.Error(), "certificate is not trusted")
+	})
+
+	t.Run("OIDC provider is Dex, TLS is configured", func(t *testing.T) {
+		dexConfig := map[string]string{
+			"url": dexTestServer.URL,
+			"dex.config": `connectors:
+- type: github
+  name: GitHub
+  config:
+    clientID: aabbccddeeff00112233
+    clientSecret: aabbccddeeff00112233`,
+		}
+
+		// This is not actually used in the test. The test only calls the OIDC test server. But a valid cert/key pair
+		// must be set to test VerifyToken's behavior when Argo CD is configured with TLS enabled.
+		secretConfig := map[string][]byte{
+			"tls.crt": utiltest.Cert,
+			"tls.key": utiltest.PrivateKey,
+		}
+
+		settingsMgr := settings.NewSettingsManager(context.Background(), getKubeClientWithConfig(dexConfig, secretConfig), "argocd")
+		mgr := NewSessionManager(settingsMgr, getProjLister(), dexTestServer.URL, NewUserStateStorage(nil))
+		mgr.verificationDelayNoiseEnabled = false
+
+		claims := jwt.StandardClaims{Audience: jwt.ClaimStrings{"test-client"}, Subject: "admin", ExpiresAt: jwt.At(time.Now().Add(time.Hour * 24))}
+		claims.Issuer = fmt.Sprintf("%s/api/dex", dexTestServer.URL)
+		token := jwt.NewWithClaims(jwt.SigningMethodRS256, claims)
+		key, err := jwt.ParseRSAPrivateKeyFromPEM(utiltest.PrivateKey)
+		require.NoError(t, err)
+		tokenString, err := token.SignedString(key)
+		require.NoError(t, err)
+
+		_, _, err = mgr.VerifyToken(tokenString)
+		assert.Error(t, err)
+		assert.Contains(t, err.Error(), "certificate signed by unknown authority")
+	})
+
+	t.Run("OIDC provider is external, TLS is configured", func(t *testing.T) {
+		dexConfig := map[string]string{
+			"url": "",
+			"oidc.config": fmt.Sprintf(`
+name: Test
+issuer: %s
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]`, oidcTestServer.URL),
+		}
+
+		// This is not actually used in the test. The test only calls the OIDC test server. But a valid cert/key pair
+		// must be set to test VerifyToken's behavior when Argo CD is configured with TLS enabled.
+		secretConfig := map[string][]byte{
+			"tls.crt": utiltest.Cert,
+			"tls.key": utiltest.PrivateKey,
+		}
+
+		settingsMgr := settings.NewSettingsManager(context.Background(), getKubeClientWithConfig(dexConfig, secretConfig), "argocd")
+		mgr := NewSessionManager(settingsMgr, getProjLister(), "", NewUserStateStorage(nil))
+		mgr.verificationDelayNoiseEnabled = false
+
+		claims := jwt.StandardClaims{Audience: jwt.ClaimStrings{"test-client"}, Subject: "admin", ExpiresAt: jwt.At(time.Now().Add(time.Hour * 24))}
+		claims.Issuer = oidcTestServer.URL
+		token := jwt.NewWithClaims(jwt.SigningMethodRS256, claims)
+		key, err := jwt.ParseRSAPrivateKeyFromPEM(utiltest.PrivateKey)
+		require.NoError(t, err)
+		tokenString, err := token.SignedString(key)
+		require.NoError(t, err)
+
+		_, _, err = mgr.VerifyToken(tokenString)
+		assert.Error(t, err)
+		assert.Contains(t, err.Error(), "certificate is not trusted")
+	})
+
+	t.Run("OIDC provider is Dex, TLS is configured", func(t *testing.T) {
+		dexConfig := map[string]string{
+			"url": dexTestServer.URL,
+			"dex.config": `connectors:
+- type: github
+  name: GitHub
+  config:
+    clientID: aabbccddeeff00112233
+    clientSecret: aabbccddeeff00112233`,
+		}
+
+		// This is not actually used in the test. The test only calls the OIDC test server. But a valid cert/key pair
+		// must be set to test VerifyToken's behavior when Argo CD is configured with TLS enabled.
+		secretConfig := map[string][]byte{
+			"tls.crt": utiltest.Cert,
+			"tls.key": utiltest.PrivateKey,
+		}
+
+		settingsMgr := settings.NewSettingsManager(context.Background(), getKubeClientWithConfig(dexConfig, secretConfig), "argocd")
+		mgr := NewSessionManager(settingsMgr, getProjLister(), dexTestServer.URL, NewUserStateStorage(nil))
+		mgr.verificationDelayNoiseEnabled = false
+
+		claims := jwt.StandardClaims{Audience: jwt.ClaimStrings{"test-client"}, Subject: "admin", ExpiresAt: jwt.At(time.Now().Add(time.Hour * 24))}
+		claims.Issuer = fmt.Sprintf("%s/api/dex", dexTestServer.URL)
+		token := jwt.NewWithClaims(jwt.SigningMethodRS256, claims)
+		key, err := jwt.ParseRSAPrivateKeyFromPEM(utiltest.PrivateKey)
+		require.NoError(t, err)
+		tokenString, err := token.SignedString(key)
+		require.NoError(t, err)
+
+		_, _, err = mgr.VerifyToken(tokenString)
+		assert.Error(t, err)
+		assert.Contains(t, err.Error(), "certificate signed by unknown authority")
+	})
+
+	t.Run("OIDC provider is external, TLS is configured, OIDCTLSInsecureSkipVerify is true", func(t *testing.T) {
+		dexConfig := map[string]string{
+			"url": "",
+			"oidc.config": fmt.Sprintf(`
+name: Test
+issuer: %s
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]`, oidcTestServer.URL),
+			"oidc.tls.insecure.skip.verify": "true",
+		}
+
+		// This is not actually used in the test. The test only calls the OIDC test server. But a valid cert/key pair
+		// must be set to test VerifyToken's behavior when Argo CD is configured with TLS enabled.
+		secretConfig := map[string][]byte{
+			"tls.crt": utiltest.Cert,
+			"tls.key": utiltest.PrivateKey,
+		}
+
+		settingsMgr := settings.NewSettingsManager(context.Background(), getKubeClientWithConfig(dexConfig, secretConfig), "argocd")
+		mgr := NewSessionManager(settingsMgr, getProjLister(), "", NewUserStateStorage(nil))
+		mgr.verificationDelayNoiseEnabled = false
+
+		claims := jwt.StandardClaims{Audience: jwt.ClaimStrings{"test-client"}, Subject: "admin", ExpiresAt: jwt.At(time.Now().Add(time.Hour * 24))}
+		claims.Issuer = oidcTestServer.URL
+		token := jwt.NewWithClaims(jwt.SigningMethodRS256, claims)
+		key, err := jwt.ParseRSAPrivateKeyFromPEM(utiltest.PrivateKey)
+		require.NoError(t, err)
+		tokenString, err := token.SignedString(key)
+		require.NoError(t, err)
+
+		_, _, err = mgr.VerifyToken(tokenString)
+		assert.NotContains(t, err.Error(), "certificate signed by unknown authority")
+	})
+
+	t.Run("OIDC provider is external, TLS is not configured, OIDCTLSInsecureSkipVerify is true", func(t *testing.T) {
+		dexConfig := map[string]string{
+			"url": "",
+			"oidc.config": fmt.Sprintf(`
+name: Test
+issuer: %s
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]`, oidcTestServer.URL),
+			"oidc.tls.insecure.skip.verify": "true",
+		}
+
+		settingsMgr := settings.NewSettingsManager(context.Background(), getKubeClientWithConfig(dexConfig, nil), "argocd")
+		mgr := NewSessionManager(settingsMgr, getProjLister(), "", NewUserStateStorage(nil))
+		mgr.verificationDelayNoiseEnabled = false
+
+		claims := jwt.StandardClaims{Audience: jwt.ClaimStrings{"test-client"}, Subject: "admin", ExpiresAt: jwt.At(time.Now().Add(time.Hour * 24))}
+		claims.Issuer = oidcTestServer.URL
+		token := jwt.NewWithClaims(jwt.SigningMethodRS256, claims)
+		key, err := jwt.ParseRSAPrivateKeyFromPEM(utiltest.PrivateKey)
+		require.NoError(t, err)
+		tokenString, err := token.SignedString(key)
+		require.NoError(t, err)
+
+		_, _, err = mgr.VerifyToken(tokenString)
+		// This is the error thrown when the test server's certificate _is_ being verified.
+		assert.NotContains(t, err.Error(), "certificate is not trusted")
+	})
+}

util/settings/settings.go

@@ -88,6 +88,11 @@ type ArgoCDSettings struct {
 	UiBannerPosition string `json:"uiBannerPosition,omitempty"`
 	// PasswordPattern for password regular expression
 	PasswordPattern string `json:"passwordPattern,omitempty"`
+	// OIDCTLSInsecureSkipVerify determines whether certificate verification is skipped when verifying tokens with the
+	// configured OIDC provider (either external or the bundled Dex instance). Setting this to `true` will cause JWT
+	// token verification to pass despite the OIDC provider having an invalid certificate. Only set to `true` if you
+	// understand the risks.
+	OIDCTLSInsecureSkipVerify bool `json:"oidcTLSInsecureSkipVerify"`
 }
 
 type GoogleAnalytics struct {
@@ -117,6 +122,7 @@ type OIDCConfig struct {
 	RequestedScopes        []string               `json:"requestedScopes,omitempty"`
 	RequestedIDTokenClaims map[string]*oidc.Claim `json:"requestedIDTokenClaims,omitempty"`
 	LogoutURL              string                 `json:"logoutURL,omitempty"`
+	RootCA                 string                 `json:"rootCA,omitempty"`
 }
 
 // DEPRECATED. Helm repository credentials are now managed using RepoCredentials
@@ -382,6 +388,8 @@ const (
 	settingsPasswordPatternKey = "passwordPattern"
 	// helmValuesFileSchemesKey is the key to configure the list of supported helm values file schemas
 	helmValuesFileSchemesKey = "helm.valuesFileSchemes"
+	// oidcTLSInsecureSkipVerifyKey is the key to configure whether TLS cert verification is skipped for OIDC connections
+	oidcTLSInsecureSkipVerifyKey = "oidc.tls.insecure.skip.verify"
 )
 
 // SettingsManager holds config info for a new manager with which to access Kubernetes ConfigMaps.
@@ -1187,6 +1195,7 @@ func updateSettingsFromConfigMap(settings *ArgoCDSettings, argoCDCM *apiv1.Confi
 	if settings.PasswordPattern == "" {
 		settings.PasswordPattern = common.PasswordPatten
 	}
+	settings.OIDCTLSInsecureSkipVerify = argoCDCM.Data[oidcTLSInsecureSkipVerifyKey] == "true"
 }
 
 // validateExternalURL ensures the external URL that is set on the configmap is valid
@@ -1551,6 +1560,33 @@ func (a *ArgoCDSettings) OAuth2ClientSecret() string {
 	return ""
 }
 
+// OIDCTLSConfig returns the TLS config for the OIDC provider. If an external provider is configured, returns a TLS
+// config using the root CAs (if any) specified in the OIDC config. If an external OIDC provider is not configured,
+// returns the API server TLS config, because the API server proxies requests to Dex.
+func (a *ArgoCDSettings) OIDCTLSConfig() *tls.Config {
+	var tlsConfig *tls.Config
+
+	oidcConfig := a.OIDCConfig()
+	if oidcConfig != nil {
+		tlsConfig = &tls.Config{}
+		if oidcConfig.RootCA != "" {
+			certPool := x509.NewCertPool()
+			ok := certPool.AppendCertsFromPEM([]byte(oidcConfig.RootCA))
+			if !ok {
+				log.Warn("failed to append certificates from PEM: proceeding without custom rootCA")
+			} else {
+				tlsConfig.RootCAs = certPool
+			}
+		}
+	} else {
+		tlsConfig = a.TLSConfig()
+	}
+	if tlsConfig != nil && a.OIDCTLSInsecureSkipVerify {
+		tlsConfig.InsecureSkipVerify = true
+	}
+	return tlsConfig
+}
+
 func appendURLPath(inputURL string, inputPath string) (string, error) {
 	u, err := url.Parse(inputURL)
 	if err != nil {

util/settings/settings_test.go

@@ -4,12 +4,17 @@ import (
 	"context"
 	"crypto/tls"
 	"crypto/x509"
+	"fmt"
 	"sort"
+	"strings"
 	"testing"
 
+	"github.com/stretchr/testify/require"
+
 	"github.com/argoproj/argo-cd/v2/common"
 	"github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
 	testutil "github.com/argoproj/argo-cd/v2/test"
+	"github.com/argoproj/argo-cd/v2/util/test"
 
 	"github.com/stretchr/testify/assert"
 	v1 "k8s.io/api/core/v1"
@@ -1016,3 +1021,68 @@ func TestGetHelmSettings(t *testing.T) {
 		})
 	}
 }
+func TestArgoCDSettings_OIDCTLSConfig_OIDCTLSInsecureSkipVerify(t *testing.T) {
+	certParsed, err := tls.X509KeyPair(test.Cert, test.PrivateKey)
+	require.NoError(t, err)
+
+	testCases := []struct{
+		name string
+		settings *ArgoCDSettings
+		expectNilTLSConfig bool
+	}{
+		{
+			name: "OIDC configured, no root CA",
+			settings: &ArgoCDSettings{OIDCConfigRAW: `name: Test
+issuer: aaa
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]`},
+		},
+		{
+			name: "OIDC configured, valid root CA",
+			settings: &ArgoCDSettings{OIDCConfigRAW: fmt.Sprintf(`
+name: Test
+issuer: aaa
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]
+rootCA: |
+  %s
+`, strings.Replace(string(test.Cert), "\n", "\n  ", -1))},
+		},
+		{
+			name: "OIDC configured, invalid root CA",
+			settings: &ArgoCDSettings{OIDCConfigRAW: `name: Test
+issuer: aaa
+clientID: xxx
+clientSecret: yyy
+requestedScopes: ["oidc"]
+rootCA: "invalid"`},
+		},
+		{
+			name: "OIDC not configured, no cert configured",
+			settings: &ArgoCDSettings{},
+			expectNilTLSConfig: true,
+		},
+		{
+			name: "OIDC not configured, cert configured",
+			settings: &ArgoCDSettings{Certificate: &certParsed},
+		},
+	}
+
+	for _, testCase := range testCases {
+		testCase := testCase
+
+		t.Run(testCase.name, func(t *testing.T) {
+			if testCase.expectNilTLSConfig {
+				assert.Nil(t, testCase.settings.OIDCTLSConfig())
+			} else {
+				assert.False(t, testCase.settings.OIDCTLSConfig().InsecureSkipVerify)
+
+				testCase.settings.OIDCTLSInsecureSkipVerify = true
+
+				assert.True(t, testCase.settings.OIDCTLSConfig().InsecureSkipVerify)
+			}
+		})
+	}
+}

util/test/testutil.go

@@ -0,0 +1,140 @@
+package test
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+// Cert is a certificate for tests. It was generated like this:
+// 		opts := tls.CertOptions{Hosts: []string{"localhost"}, Organization: "Acme"}
+//		certBytes, privKey, err := tls.generatePEM(opts)
+var Cert = []byte(`-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`)
+
+// PrivateKey is an RSA key used only for tests.
+var PrivateKey = []byte(`-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----`)
+
+func dexMockHandler(t *testing.T, url string) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch r.RequestURI {
+		case "/api/dex/.well-known/openid-configuration":
+			_, err := io.WriteString(w, fmt.Sprintf(`
+{
+  "issuer": "%[1]s/api/dex",
+  "authorization_endpoint": "%[1]s/api/dex/auth",
+  "token_endpoint": "%[1]s/api/dex/token",
+  "jwks_uri": "%[1]s/api/dex/keys",
+  "userinfo_endpoint": "%[1]s/api/dex/userinfo",
+  "device_authorization_endpoint": "%[1]s/api/dex/device/code",
+  "grant_types_supported": ["authorization_code"],
+  "response_types_supported": ["code"],
+  "subject_types_supported": ["public"],
+  "id_token_signing_alg_values_supported": ["RS512"],
+  "code_challenge_methods_supported": ["S256", "plain"],
+  "scopes_supported": ["openid"],
+  "token_endpoint_auth_methods_supported": ["client_secret_basic", "client_secret_post"],
+  "claims_supported": ["sub", "aud", "exp"]
+}`, url))
+			require.NoError(t, err)
+		default:
+			w.WriteHeader(404)
+		}
+	}
+}
+
+func GetDexTestServer(t *testing.T) *httptest.Server {
+	ts := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Start with a placeholder. We need the server URL before setting up the real handler.
+	}))
+	ts.Config.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		dexMockHandler(t, ts.URL)(w, r)
+	})
+	return ts
+}
+
+func oidcMockHandler(t *testing.T, url string) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		switch r.RequestURI {
+		case "/.well-known/openid-configuration":
+			_, err := io.WriteString(w, fmt.Sprintf(`
+{
+  "issuer": "%[1]s",
+  "authorization_endpoint": "%[1]s/auth",
+  "token_endpoint": "%[1]s/token",
+  "jwks_uri": "%[1]s/keys",
+  "userinfo_endpoint": "%[1]s/userinfo",
+  "device_authorization_endpoint": "%[1]s/device/code",
+  "grant_types_supported": ["authorization_code"],
+  "response_types_supported": ["code"],
+  "subject_types_supported": ["public"],
+  "id_token_signing_alg_values_supported": ["RS512"],
+  "code_challenge_methods_supported": ["S256", "plain"],
+  "scopes_supported": ["openid"],
+  "token_endpoint_auth_methods_supported": ["client_secret_basic", "client_secret_post"],
+  "claims_supported": ["sub", "aud", "exp"]
+}`, url))
+			require.NoError(t, err)
+		default:
+			w.WriteHeader(404)
+		}
+	}
+}
+
+func GetOIDCTestServer(t *testing.T) *httptest.Server {
+	ts := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Start with a placeholder. We need the server URL before setting up the real handler.
+	}))
+	ts.Config.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		oidcMockHandler(t, ts.URL)(w, r)
+	})
+	return ts
+}

util/webhook/webhook.go

@@ -270,7 +270,7 @@ func (a *ArgoCDWebhookHandler) storePreviouslyCachedManifests(app *v1alpha1.Appl
 		return err
 	}
 	var cachedManifests cache.CachedManifestResponse
-	if err := a.repoCache.GetManifests(change.shaBefore, &app.Spec.Source, &clusterInfo, app.Spec.Destination.Namespace, trackingMethod, appInstanceLabelKey, app.Name, &cachedManifests); err == nil {
+	if err := a.repoCache.GetManifests(change.shaBefore, &app.Spec.Source, &clusterInfo, app.Spec.Destination.Namespace, trackingMethod, appInstanceLabelKey, app.Name, &cachedManifests); err != nil {
 		return err
 	}
 	if err = a.repoCache.SetManifests(change.shaAfter, &app.Spec.Source, &clusterInfo, app.Spec.Destination.Namespace, trackingMethod, appInstanceLabelKey, app.Name, &cachedManifests); err != nil {