Add support for ignoring invalid cert options in the x509 clients used for instance principal

Currently the option to ignore server cert errors is only applied to clients that Terraform has explicitly created.
However, this misses clients that are implicitly created by the OCI SDK to handle requests to auth services.

Author: alexng-canuck

oci/provider.go

@@ -837,6 +837,7 @@ func getConfigProviders(d *schema.ResourceData, auth string) ([]oci_common.Confi
 
 	switch auth {
 	case strings.ToLower(authAPIKeySetting):
+		// No additional config providers needed
 	case strings.ToLower(authInstancePrincipalSetting):
 		apiKeyConfigVariablesToUnset, ok := checkIncompatibleAttrsForApiKeyAuth(d)
 		if !ok {
@@ -847,7 +848,21 @@ func getConfigProviders(d *schema.ResourceData, auth string) ([]oci_common.Confi
 		if !ok {
 			return nil, fmt.Errorf("can not get %s from Terraform configuration (InstancePrincipal)", regionAttrName)
 		}
-		cfg, err := oci_common_auth.InstancePrincipalConfigurationProviderForRegion(oci_common.StringToRegion(region.(string)))
+
+		// Used to modify InstancePrincipal auth clients so that `accept_local_certs` is honored for auth clients as well
+		// These clients are created implicitly by SDK, and are not modified by the buildConfigureClientFn that usually does this for the other SDK clients
+		instancePrincipalAuthClientModifier := func(client oci_common.HTTPRequestDispatcher) (oci_common.HTTPRequestDispatcher, error) {
+			if acceptLocalCerts := getEnvSettingWithBlankDefault(acceptLocalCerts); acceptLocalCerts != "" {
+				if bool, err := strconv.ParseBool(acceptLocalCerts); err == nil {
+					modifiedClient := buildHttpClient()
+					modifiedClient.Transport.(*http.Transport).TLSClientConfig.InsecureSkipVerify = bool
+					return modifiedClient, nil
+				}
+			}
+			return client, nil
+		}
+
+		cfg, err := oci_common_auth.InstancePrincipalConfigurationForRegionWithCustomClient(oci_common.StringToRegion(region.(string)), instancePrincipalAuthClientModifier)
 		if err != nil {
 			return nil, err
 		}