mono/mcs/class/referencesource/System.ServiceModel/System/ServiceModel/Configuration/ConfigurationHelpers.cs

//------------------------------------------------------------------------------
// Copyright (c) Microsoft Corporation.  All rights reserved.
//------------------------------------------------------------------------------
namespace System.ServiceModel.Configuration
{
    using System;
    using System.Collections.Generic;
    using System.Configuration;
    using System.Diagnostics;
    using System.Reflection;
    using System.Runtime;
    using System.Runtime.Diagnostics;
    using System.Security;
    using System.Security.Permissions;
    using System.ServiceModel;
    using System.ServiceModel.Activation;
    using System.ServiceModel.Diagnostics;

    static class ConfigurationHelpers
    {
        /// Be sure to update UnsafeGetAssociatedBindingCollectionElement if you modify this method
        internal static BindingCollectionElement GetAssociatedBindingCollectionElement(ContextInformation evaluationContext, string bindingCollectionName)
        {
            BindingCollectionElement retVal = null;
            BindingsSection bindingsSection = (BindingsSection)ConfigurationHelpers.GetAssociatedSection(evaluationContext, ConfigurationStrings.BindingsSectionGroupPath);

            if (null != bindingsSection)
            {
                bindingsSection.UpdateBindingSections(evaluationContext);
                try
                {
                    retVal = bindingsSection[bindingCollectionName];
                }
                catch (KeyNotFoundException)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigBindingExtensionNotFound,
                        ConfigurationHelpers.GetBindingsSectionPath(bindingCollectionName))));
                }
                catch (NullReferenceException) // System.Configuration.ConfigurationElement bug
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigBindingExtensionNotFound,
                        ConfigurationHelpers.GetBindingsSectionPath(bindingCollectionName))));
                }
            }

            return retVal;
        }

        // Be sure to update GetAssociatedBindingCollectionElement if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical method UnsafeGetAssociatedSection which elevates.")]
        [SecurityCritical]
        internal static BindingCollectionElement UnsafeGetAssociatedBindingCollectionElement(ContextInformation evaluationContext, string bindingCollectionName)
        {
            BindingCollectionElement retVal = null;
            BindingsSection bindingsSection = (BindingsSection)ConfigurationHelpers.UnsafeGetAssociatedSection(evaluationContext, ConfigurationStrings.BindingsSectionGroupPath);

            if (null != bindingsSection)
            {
                bindingsSection.UpdateBindingSections(evaluationContext);
                try
                {
                    retVal = bindingsSection[bindingCollectionName];
                }
                catch (KeyNotFoundException)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigBindingExtensionNotFound,
                        ConfigurationHelpers.GetBindingsSectionPath(bindingCollectionName))));
                }
                catch (NullReferenceException) // System.Configuration.ConfigurationElement bug
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigBindingExtensionNotFound,
                        ConfigurationHelpers.GetBindingsSectionPath(bindingCollectionName))));
                }
            }

            return retVal;
        }

        /// Be sure to update UnsafeGetAssociatedEndpointCollectionElement if you modify this method
        internal static EndpointCollectionElement GetAssociatedEndpointCollectionElement(ContextInformation evaluationContext, string endpointCollectionName)
        {
            EndpointCollectionElement retVal = null;
            StandardEndpointsSection endpointsSection = (StandardEndpointsSection)ConfigurationHelpers.GetAssociatedSection(evaluationContext, ConfigurationStrings.StandardEndpointsSectionPath);

            if (null != endpointsSection)
            {
                endpointsSection.UpdateEndpointSections(evaluationContext);
                try
                {
                    retVal = (EndpointCollectionElement)endpointsSection[endpointCollectionName];
                }
                catch (KeyNotFoundException)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigEndpointExtensionNotFound,
                        ConfigurationHelpers.GetEndpointsSectionPath(endpointCollectionName))));
                }
                catch (NullReferenceException) // System.Configuration.ConfigurationElement bug
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigEndpointExtensionNotFound,
                        ConfigurationHelpers.GetEndpointsSectionPath(endpointCollectionName))));
                }
            }

            return retVal;
        }

        // Be sure to update GetAssociatedEndpointCollectionElement if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical method UnsafeGetAssociatedSection which elevates.")]
        [SecurityCritical]
        internal static EndpointCollectionElement UnsafeGetAssociatedEndpointCollectionElement(ContextInformation evaluationContext, string endpointCollectionName)
        {
            EndpointCollectionElement retVal = null;
            StandardEndpointsSection endpointsSection = (StandardEndpointsSection)ConfigurationHelpers.UnsafeGetAssociatedSection(evaluationContext, ConfigurationStrings.StandardEndpointsSectionPath);

            if (null != endpointsSection)
            {
                endpointsSection.UpdateEndpointSections(evaluationContext);
                try
                {
                    retVal = (EndpointCollectionElement)endpointsSection[endpointCollectionName];
                }
                catch (KeyNotFoundException)
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigEndpointExtensionNotFound,
                        ConfigurationHelpers.GetEndpointsSectionPath(endpointCollectionName))));
                }
                catch (NullReferenceException) // System.Configuration.ConfigurationElement bug
                {
                    throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                        new ConfigurationErrorsException(SR.GetString(SR.ConfigEndpointExtensionNotFound,
                        ConfigurationHelpers.GetEndpointsSectionPath(endpointCollectionName))));
                }
            }

            return retVal;
        }

        /// Be sure to update UnsafeGetAssociatedSection if you modify this method
        internal static object GetAssociatedSection(ContextInformation evalContext, string sectionPath)
        {
            object retval = null;
            if (evalContext != null)
            {
                retval = evalContext.GetSection(sectionPath);
            }
            else
            {
                retval = AspNetEnvironment.Current.GetConfigurationSection(sectionPath);

                // Trace after call to underlying configuration system to
                // insure that configuration system is initialized
                if (DiagnosticUtility.ShouldTraceVerbose)
                {
                    TraceUtility.TraceEvent(TraceEventType.Verbose, TraceCode.GetConfigurationSection,
                        SR.GetString(SR.TraceCodeGetConfigurationSection),
                        new StringTraceRecord("ConfigurationSection", sectionPath), null, null);
                }
            }
            if (retval == null)
            {
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                    new ConfigurationErrorsException(SR.GetString(SR.ConfigSectionNotFound,
                    sectionPath)));
            }
            return retval;
        }

        // Be sure to update GetAssociatedSection if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical methods which elevate.")]
        [SecurityCritical]
        internal static object UnsafeGetAssociatedSection(ContextInformation evalContext, string sectionPath)
        {
            object retval = null;
            if (evalContext != null)
            {
                retval = UnsafeGetSectionFromContext(evalContext, sectionPath);
            }
            else
            {
                retval = AspNetEnvironment.Current.UnsafeGetConfigurationSection(sectionPath);

                // Trace after call to underlying configuration system to
                // insure that configuration system is initialized
                if (DiagnosticUtility.ShouldTraceVerbose)
                {
                    TraceUtility.TraceEvent(TraceEventType.Verbose, TraceCode.GetConfigurationSection,
                        SR.GetString(SR.TraceCodeGetConfigurationSection),
                        new StringTraceRecord("ConfigurationSection", sectionPath), null, null);
                }
            }
            if (retval == null)
            {
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                    new ConfigurationErrorsException(SR.GetString(SR.ConfigSectionNotFound,
                    sectionPath)));
            }

            return retval;
        }

        /// Be sure to update UnsafeGetBindingCollectionElement if you modify this method
        internal static BindingCollectionElement GetBindingCollectionElement(string bindingCollectionName)
        {
            return GetAssociatedBindingCollectionElement(null, bindingCollectionName);
        }

        // Be sure to update GetBindingCollectionElement if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical method UnsafeGetAssociatedBindingCollectionElement which elevates.")]
        [SecurityCritical]
        internal static BindingCollectionElement UnsafeGetBindingCollectionElement(string bindingCollectionName)
        {
            return UnsafeGetAssociatedBindingCollectionElement(null, bindingCollectionName);
        }

        internal static string GetBindingsSectionPath(string sectionName)
        {
            return string.Concat(ConfigurationStrings.BindingsSectionGroupPath, "/", sectionName);
        }

        internal static string GetEndpointsSectionPath(string sectionName)
        {
            return string.Concat(ConfigurationStrings.StandardEndpointsSectionName, "/", sectionName);
        }

        /// Be sure to update UnsafeGetEndpointCollectionElement if you modify this method
        internal static EndpointCollectionElement GetEndpointCollectionElement(string endpointCollectionName)
        {
            return GetAssociatedEndpointCollectionElement(null, endpointCollectionName);
        }

        // Be sure to update GetEndpointCollectionElement if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical method UnsafeGetAssociatedEndpointCollectionElement which elevates.")]
        [SecurityCritical]
        internal static EndpointCollectionElement UnsafeGetEndpointCollectionElement(string endpointCollectionName)
        {
            return UnsafeGetAssociatedEndpointCollectionElement(null, endpointCollectionName);
        }

        /// Be sure to update UnsafeGetSection if you modify this method
        internal static object GetSection(string sectionPath)
        {
            return GetAssociatedSection(null, sectionPath);
        }

        // Be sure to update GetSection if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical method UnsafeGetAssociatedSection which elevates.")]
        [SecurityCritical]
        internal static object UnsafeGetSection(string sectionPath)
        {
            return UnsafeGetAssociatedSection(null, sectionPath);
        }

        // Be sure to update UnsafeGetSection if you modify this method
        [Fx.Tag.SecurityNote(Critical = "Uses SecurityCritical method UnsafeGetAssociatedSection which elevates.")]
        [SecurityCritical]
        internal static object UnsafeGetSectionNoTrace(string sectionPath)
        {
            object retval = AspNetEnvironment.Current.UnsafeGetConfigurationSection(sectionPath);

            if (retval == null)
            {
                throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
                    new ConfigurationErrorsException(SR.GetString(SR.ConfigSectionNotFound,
                    sectionPath)));
            }

            return retval;
        }

        [Fx.Tag.SecurityNote(Critical = "Asserts ConfigurationPermission in order to fetch config from ContextInformation,"
            + "caller must guard return value.")]
        [SecurityCritical]
        [ConfigurationPermission(SecurityAction.Assert, Unrestricted = true)]
        internal static object UnsafeGetSectionFromContext(ContextInformation evalContext, string sectionPath)
        {
            return evalContext.GetSection(sectionPath);
        }

        internal static string GetSectionPath(string sectionName)
        {
            return string.Concat(ConfigurationStrings.SectionGroupName, "/", sectionName);
        }

        [Fx.Tag.SecurityNote(Critical = "Calls SetIsPresentWithAssert which elevates in order to set a property."
            + "Caller must guard ConfigurationElement parameter, ie only pass 'this'.")]
        [SecurityCritical]
        internal static void SetIsPresent(ConfigurationElement element)
        {
            // Work around for VSW 578830: ConfigurationElements that override DeserializeElement cannot set ElementInformation.IsPresent
            PropertyInfo elementPresent = element.GetType().GetProperty("ElementPresent", BindingFlags.Instance | BindingFlags.NonPublic);
            SetIsPresentWithAssert(elementPresent, element, true);
        }

        [Fx.Tag.SecurityNote(Critical = "Asserts full trust in order to set a private member in the ConfigurationElement."
            + "Caller must guard parameters.")]
        [SecurityCritical]
        [PermissionSet(SecurityAction.Assert, Unrestricted = true)]
        static void SetIsPresentWithAssert(PropertyInfo elementPresent, ConfigurationElement element, bool value)
        {
            elementPresent.SetValue(element, value, null);
        }

        internal static ContextInformation GetEvaluationContext(IConfigurationContextProviderInternal provider)
        {
            if (provider != null)
            {
                try
                {
                    return provider.GetEvaluationContext();
                }
                catch (ConfigurationErrorsException)
                {
                }
            }
            return null;
        }

        [Fx.Tag.SecurityNote(Miscellaneous = "RequiresReview - The return value will be used for a security decision. if in doubt about the return value, "
            + "it is safe to return null (caller will assume the worst case from a security perspective).")]
        internal static ContextInformation GetOriginalEvaluationContext(IConfigurationContextProviderInternal provider)
        {
            if (provider != null)
            {
                // provider may not need this try/catch, but it doesn't hurt to do it
                try
                {
                    return provider.GetOriginalEvaluationContext();
                }
                catch (ConfigurationErrorsException)
                {
                }
            }
            return null;
        }

        internal static void TraceExtensionTypeNotFound(ExtensionElement extensionElement)
        {
            if (DiagnosticUtility.ShouldTraceWarning)
            {
                Dictionary<string, string> values = new Dictionary<string, string>(2);
                values.Add("ExtensionName", extensionElement.Name);
                values.Add("ExtensionType", extensionElement.Type);

                DictionaryTraceRecord traceRecord = new DictionaryTraceRecord(values);
                TraceUtility.TraceEvent(TraceEventType.Warning,
                    TraceCode.ExtensionTypeNotFound,
                    SR.GetString(SR.TraceCodeExtensionTypeNotFound),
                    traceRecord,
                    null,
                    (Exception)null);
            }
        }
    }

    interface IConfigurationContextProviderInternal
    {
        /// <summary>
        /// return the current ContextInformation (the protected property ConfigurationElement.EvaluationContext)
        /// this may throw ConfigurationErrorsException, caller should guard (see ConfigurationHelpers.GetEvaluationContext)
        /// </summary>
        /// <returns>result of ConfigurationElement.EvaluationContext</returns>
        ContextInformation GetEvaluationContext();

        /// <summary>
        /// return the ContextInformation that was present when the ConfigurationElement was first deserialized.
        /// if Reset was called, this will be the value of parent.GetOriginalEvaluationContext()
        /// if Reset was not called, this will be the value of this.GetEvaluationContext()
        /// </summary>
        /// <returns>result of parent's ConfigurationElement.EvaluationContext</returns>
        [Fx.Tag.SecurityNote(Miscellaneous =
            "RequiresReview - the return value will be used for a security decision. if in doubt about the return value, it "
            + "is safe (from a security perspective)  to return null (caller will assume the worst case).")]
        ContextInformation GetOriginalEvaluationContext();
    }

    [Fx.Tag.SecurityNote(Critical = "Stores information used in a security decision.")]
#pragma warning disable 618 // have not moved to the v4 security model yet
    [SecurityCritical(SecurityCriticalScope.Everything)]
#pragma warning restore 618
    struct EvaluationContextHelper
    {
        bool reset;
        ContextInformation inheritedContext;

        internal void OnReset(ConfigurationElement parent)
        {
            this.reset = true;
            this.inheritedContext = ConfigurationHelpers.GetOriginalEvaluationContext(parent as IConfigurationContextProviderInternal);
        }

        internal ContextInformation GetOriginalContext(IConfigurationContextProviderInternal owner)
        {
            if (this.reset)
            {
                // if reset, inherited context is authoritative, even if null
                return this.inheritedContext;
            }
            else
            {
                // otherwise use current
                return ConfigurationHelpers.GetEvaluationContext(owner);
            }
        }
    }
}