DPAPIProtectedConfigurationProvider.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Configuration / System / Configuration / DPAPIProtectedConfigurationProvider.cs / 1560018 / DPAPIProtectedConfigurationProvider.cs

                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Configuration 
{ 
    using System.Collections.Specialized;
    using System.Runtime.Serialization; 
    using System.Configuration.Provider;
    using System.Xml;
    using System.Text;
    using  System.Runtime.InteropServices; 
    using Microsoft.Win32;
    using System.Security.Permissions; 
    using Microsoft.Win32.SafeHandles; 
    using System.Runtime.CompilerServices;
 
    [PermissionSet(SecurityAction.Demand, Name = "FullTrust")]
    public sealed class DpapiProtectedConfigurationProvider : ProtectedConfigurationProvider
    {
        public override XmlNode Decrypt(XmlNode encryptedNode) 
        {
            if (encryptedNode.NodeType != XmlNodeType.Element || 
                encryptedNode.Name != "EncryptedData") { 
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data));
            } 

            XmlNode cipherNode = TraverseToChild(encryptedNode, "CipherData", false);
            if (cipherNode == null)
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data)); 

            XmlNode cipherValue = TraverseToChild(cipherNode, "CipherValue", true); 
            if (cipherValue == null) 
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data));
 
            string encText = cipherValue.InnerText;
            if (encText == null)
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data));
 
            string decText = DecryptText(encText);
            XmlDocument xmlDocument = new XmlDocument(); 
            xmlDocument.PreserveWhitespace = true; 
            xmlDocument.LoadXml(decText);
            return xmlDocument.DocumentElement; 
        }

        public override XmlNode Encrypt(XmlNode node)
        { 
            string text = node.OuterXml;
            string encText = EncryptText(text); 
            string pre = @""; 
            string post = @"";
            string xmlText = pre + encText + post; 

            XmlDocument xmlDocument = new XmlDocument();
            xmlDocument.PreserveWhitespace = true;
            xmlDocument.LoadXml(xmlText); 
            return xmlDocument.DocumentElement;
        } 
 

        ////////////////////////////////////////////////////////////////////// 
        //////////////////////////////////////////////////////////////////////
        //////////////////////////////////////////////////////////////////////
        private string EncryptText(string clearText)
        { 
            if (clearText == null || clearText.Length < 1)
                return clearText; 
 
            DATA_BLOB inputData, entData, outputData;
            SafeNativeMemoryHandle safeInputDataHandle = new SafeNativeMemoryHandle(); 
            SafeNativeMemoryHandle safeOutputDataHandle = new SafeNativeMemoryHandle(true);
            SafeNativeMemoryHandle safeEntDataHandle = new SafeNativeMemoryHandle();

            inputData.pbData = entData.pbData = outputData.pbData = IntPtr.Zero; 
            inputData.cbData = entData.cbData = outputData.cbData = 0;
            try { 
 
                RuntimeHelpers.PrepareConstrainedRegions();
                try { 
                }
                finally {
                    inputData = PrepareDataBlob(clearText);
                    safeInputDataHandle.SetDataHandle(inputData.pbData); 

                    entData = PrepareDataBlob(_KeyEntropy); 
                    safeEntDataHandle.SetDataHandle(entData.pbData); 
                }
 
                CRYPTPROTECT_PROMPTSTRUCT   prompt      = PreparePromptStructure();
                UInt32                      dwFlags     = CRYPTPROTECT_UI_FORBIDDEN;
                if (UseMachineProtection)
                    dwFlags |= CRYPTPROTECT_LOCAL_MACHINE; 
                bool success = false;
 
                RuntimeHelpers.PrepareConstrainedRegions(); 
                try {
                } 
                finally {
                    success = UnsafeNativeMethods.CryptProtectData(ref inputData, "", ref entData,
                                                                    IntPtr.Zero, ref prompt,
                                                                    dwFlags, ref outputData); 
                    safeOutputDataHandle.SetDataHandle(outputData.pbData);
                } 
                if (!success || outputData.pbData == IntPtr.Zero) { 
                    outputData.pbData = IntPtr.Zero;
                    Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error()); 
                }
                byte[] buf = new byte[outputData.cbData];
                Marshal.Copy(outputData.pbData, buf, 0, buf.Length);
                return Convert.ToBase64String(buf); 
            } finally {
                if (!(safeOutputDataHandle == null || safeOutputDataHandle.IsInvalid)) { 
                    safeOutputDataHandle.Dispose(); 
                    outputData.pbData = IntPtr.Zero;
                } 
                if (!(safeEntDataHandle == null || safeEntDataHandle.IsInvalid)) {
                    safeEntDataHandle.Dispose();
                    entData.pbData = IntPtr.Zero;
                } 
                if (!(safeInputDataHandle == null || safeInputDataHandle.IsInvalid)) {
                    safeInputDataHandle.Dispose(); 
                    inputData.pbData = IntPtr.Zero; 
                }
            } 
        }

        //////////////////////////////////////////////////////////////////////
        ////////////////////////////////////////////////////////////////////// 
        //////////////////////////////////////////////////////////////////////
        private string DecryptText(string encText) 
        { 
            if (encText == null || encText.Length < 1)
                return encText; 

            DATA_BLOB inputData, entData, outputData;
            SafeNativeMemoryHandle safeInputDataHandle = new SafeNativeMemoryHandle();
            SafeNativeMemoryHandle safeOutputDataHandle = new SafeNativeMemoryHandle(true); 
            SafeNativeMemoryHandle safeEntDataHandle = new SafeNativeMemoryHandle();
 
            inputData.pbData = entData.pbData = outputData.pbData = IntPtr.Zero; 
            inputData.cbData = entData.cbData = outputData.cbData = 0;
 
            try {
                RuntimeHelpers.PrepareConstrainedRegions();
                try {
                } 
                finally {
                    inputData = PrepareDataBlob(Convert.FromBase64String(encText)); 
                    safeInputDataHandle.SetDataHandle(inputData.pbData); 

                    entData = PrepareDataBlob(_KeyEntropy); 
                    safeEntDataHandle.SetDataHandle(entData.pbData);
                }

                CRYPTPROTECT_PROMPTSTRUCT   prompt      = PreparePromptStructure(); 
                UInt32                      dwFlags     = CRYPTPROTECT_UI_FORBIDDEN;
 
                if (UseMachineProtection) 
                    dwFlags |= CRYPTPROTECT_LOCAL_MACHINE;
                bool success = false; 
                RuntimeHelpers.PrepareConstrainedRegions();
                try {
                }
                finally { 
                    success = UnsafeNativeMethods.CryptUnprotectData(ref inputData, IntPtr.Zero,
                                                                      ref entData, IntPtr.Zero, 
                                                                      ref prompt, dwFlags, ref outputData); 
                    safeOutputDataHandle.SetDataHandle(outputData.pbData);
                } 

                if (!success || outputData.pbData == IntPtr.Zero) {
                    outputData.pbData = IntPtr.Zero;
                    Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error()); 
                }
                byte[] buf = new byte[outputData.cbData]; 
                Marshal.Copy(outputData.pbData, buf, 0, buf.Length); 
                return Encoding.Unicode.GetString(buf);
            } finally { 
                if (!(safeOutputDataHandle == null || safeOutputDataHandle.IsInvalid)) {
                    safeOutputDataHandle.Dispose();
                    outputData.pbData = IntPtr.Zero;
                } 
                if (!(safeEntDataHandle == null || safeEntDataHandle.IsInvalid)) {
                    safeEntDataHandle.Dispose(); 
                    entData.pbData = IntPtr.Zero; 
                }
                if (!(safeInputDataHandle == null || safeInputDataHandle.IsInvalid)) { 
                    safeInputDataHandle.Dispose();
                    inputData.pbData = IntPtr.Zero;
                }
            } 
        }
 
        public bool     UseMachineProtection   { get { return _UseMachineProtection; }} 
        //private virtual string   KeyEntropy    { get { return _KeyEntropy; } }
 
        public override void Initialize(string name, NameValueCollection configurationValues)
        {
            base.Initialize(name, configurationValues);
            _UseMachineProtection = GetBooleanValue(configurationValues, "useMachineProtection", true); 
            _KeyEntropy = configurationValues["keyEntropy"];
            configurationValues.Remove("keyEntropy"); 
            if (configurationValues.Count > 0) 
                throw new ConfigurationErrorsException(SR.GetString(SR.Unrecognized_initialization_value, configurationValues.GetKey(0)));
        } 

        private const int CRYPTPROTECT_UI_FORBIDDEN = 0x1;
        private const int CRYPTPROTECT_LOCAL_MACHINE = 0x4;
        private bool   _UseMachineProtection = true; 
        private string  _KeyEntropy;
 
        private static XmlNode TraverseToChild(XmlNode node, string name, bool onlyChild) 
        {
            foreach (XmlNode child in node.ChildNodes) 
            {
                if (child.NodeType != XmlNodeType.Element)
                    continue;
 
                if (child.Name == name)
                    return child; // found it! 
 
                if (onlyChild)
                    return null; 
            }

            return null;
        } 

        private static DATA_BLOB PrepareDataBlob(byte[] buf) 
        { 
            if (buf == null)
                buf = new byte[0]; 
            DATA_BLOB db = new DATA_BLOB();
            db.cbData = buf.Length;
            db.pbData = Marshal.AllocHGlobal(db.cbData);
            Marshal.Copy(buf, 0, db.pbData, db.cbData); 
            return db;
        } 
        private static DATA_BLOB PrepareDataBlob(string s) 
        {
            return PrepareDataBlob((s != null) ? Encoding.Unicode.GetBytes(s) : new byte[0]); 
        }
        private static CRYPTPROTECT_PROMPTSTRUCT PreparePromptStructure()
        {
            CRYPTPROTECT_PROMPTSTRUCT cps = new CRYPTPROTECT_PROMPTSTRUCT(); 
            cps.cbSize = Marshal.SizeOf(typeof(CRYPTPROTECT_PROMPTSTRUCT));
            cps.dwPromptFlags = 0; 
            cps.hwndApp = IntPtr.Zero; 
            cps.szPrompt = null;
            return cps; 
        }
        private static bool GetBooleanValue(NameValueCollection configurationValues, string valueName, bool defaultValue) {
            string s = configurationValues[valueName];
            if (s == null) 
                return defaultValue;
            configurationValues.Remove(valueName); 
            if (s == "true") 
                return true;
            if (s == "false") 
                return false;
            throw new ConfigurationErrorsException(SR.GetString(SR.Config_invalid_boolean_attribute, valueName));
        }
    } 

} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Configuration 
{ 
    using System.Collections.Specialized;
    using System.Runtime.Serialization; 
    using System.Configuration.Provider;
    using System.Xml;
    using System.Text;
    using  System.Runtime.InteropServices; 
    using Microsoft.Win32;
    using System.Security.Permissions; 
    using Microsoft.Win32.SafeHandles; 
    using System.Runtime.CompilerServices;
 
    [PermissionSet(SecurityAction.Demand, Name = "FullTrust")]
    public sealed class DpapiProtectedConfigurationProvider : ProtectedConfigurationProvider
    {
        public override XmlNode Decrypt(XmlNode encryptedNode) 
        {
            if (encryptedNode.NodeType != XmlNodeType.Element || 
                encryptedNode.Name != "EncryptedData") { 
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data));
            } 

            XmlNode cipherNode = TraverseToChild(encryptedNode, "CipherData", false);
            if (cipherNode == null)
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data)); 

            XmlNode cipherValue = TraverseToChild(cipherNode, "CipherValue", true); 
            if (cipherValue == null) 
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data));
 
            string encText = cipherValue.InnerText;
            if (encText == null)
                throw new ConfigurationErrorsException(SR.GetString(SR.DPAPI_bad_data));
 
            string decText = DecryptText(encText);
            XmlDocument xmlDocument = new XmlDocument(); 
            xmlDocument.PreserveWhitespace = true; 
            xmlDocument.LoadXml(decText);
            return xmlDocument.DocumentElement; 
        }

        public override XmlNode Encrypt(XmlNode node)
        { 
            string text = node.OuterXml;
            string encText = EncryptText(text); 
            string pre = @""; 
            string post = @"";
            string xmlText = pre + encText + post; 

            XmlDocument xmlDocument = new XmlDocument();
            xmlDocument.PreserveWhitespace = true;
            xmlDocument.LoadXml(xmlText); 
            return xmlDocument.DocumentElement;
        } 
 

        ////////////////////////////////////////////////////////////////////// 
        //////////////////////////////////////////////////////////////////////
        //////////////////////////////////////////////////////////////////////
        private string EncryptText(string clearText)
        { 
            if (clearText == null || clearText.Length < 1)
                return clearText; 
 
            DATA_BLOB inputData, entData, outputData;
            SafeNativeMemoryHandle safeInputDataHandle = new SafeNativeMemoryHandle(); 
            SafeNativeMemoryHandle safeOutputDataHandle = new SafeNativeMemoryHandle(true);
            SafeNativeMemoryHandle safeEntDataHandle = new SafeNativeMemoryHandle();

            inputData.pbData = entData.pbData = outputData.pbData = IntPtr.Zero; 
            inputData.cbData = entData.cbData = outputData.cbData = 0;
            try { 
 
                RuntimeHelpers.PrepareConstrainedRegions();
                try { 
                }
                finally {
                    inputData = PrepareDataBlob(clearText);
                    safeInputDataHandle.SetDataHandle(inputData.pbData); 

                    entData = PrepareDataBlob(_KeyEntropy); 
                    safeEntDataHandle.SetDataHandle(entData.pbData); 
                }
 
                CRYPTPROTECT_PROMPTSTRUCT   prompt      = PreparePromptStructure();
                UInt32                      dwFlags     = CRYPTPROTECT_UI_FORBIDDEN;
                if (UseMachineProtection)
                    dwFlags |= CRYPTPROTECT_LOCAL_MACHINE; 
                bool success = false;
 
                RuntimeHelpers.PrepareConstrainedRegions(); 
                try {
                } 
                finally {
                    success = UnsafeNativeMethods.CryptProtectData(ref inputData, "", ref entData,
                                                                    IntPtr.Zero, ref prompt,
                                                                    dwFlags, ref outputData); 
                    safeOutputDataHandle.SetDataHandle(outputData.pbData);
                } 
                if (!success || outputData.pbData == IntPtr.Zero) { 
                    outputData.pbData = IntPtr.Zero;
                    Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error()); 
                }
                byte[] buf = new byte[outputData.cbData];
                Marshal.Copy(outputData.pbData, buf, 0, buf.Length);
                return Convert.ToBase64String(buf); 
            } finally {
                if (!(safeOutputDataHandle == null || safeOutputDataHandle.IsInvalid)) { 
                    safeOutputDataHandle.Dispose(); 
                    outputData.pbData = IntPtr.Zero;
                } 
                if (!(safeEntDataHandle == null || safeEntDataHandle.IsInvalid)) {
                    safeEntDataHandle.Dispose();
                    entData.pbData = IntPtr.Zero;
                } 
                if (!(safeInputDataHandle == null || safeInputDataHandle.IsInvalid)) {
                    safeInputDataHandle.Dispose(); 
                    inputData.pbData = IntPtr.Zero; 
                }
            } 
        }

        //////////////////////////////////////////////////////////////////////
        ////////////////////////////////////////////////////////////////////// 
        //////////////////////////////////////////////////////////////////////
        private string DecryptText(string encText) 
        { 
            if (encText == null || encText.Length < 1)
                return encText; 

            DATA_BLOB inputData, entData, outputData;
            SafeNativeMemoryHandle safeInputDataHandle = new SafeNativeMemoryHandle();
            SafeNativeMemoryHandle safeOutputDataHandle = new SafeNativeMemoryHandle(true); 
            SafeNativeMemoryHandle safeEntDataHandle = new SafeNativeMemoryHandle();
 
            inputData.pbData = entData.pbData = outputData.pbData = IntPtr.Zero; 
            inputData.cbData = entData.cbData = outputData.cbData = 0;
 
            try {
                RuntimeHelpers.PrepareConstrainedRegions();
                try {
                } 
                finally {
                    inputData = PrepareDataBlob(Convert.FromBase64String(encText)); 
                    safeInputDataHandle.SetDataHandle(inputData.pbData); 

                    entData = PrepareDataBlob(_KeyEntropy); 
                    safeEntDataHandle.SetDataHandle(entData.pbData);
                }

                CRYPTPROTECT_PROMPTSTRUCT   prompt      = PreparePromptStructure(); 
                UInt32                      dwFlags     = CRYPTPROTECT_UI_FORBIDDEN;
 
                if (UseMachineProtection) 
                    dwFlags |= CRYPTPROTECT_LOCAL_MACHINE;
                bool success = false; 
                RuntimeHelpers.PrepareConstrainedRegions();
                try {
                }
                finally { 
                    success = UnsafeNativeMethods.CryptUnprotectData(ref inputData, IntPtr.Zero,
                                                                      ref entData, IntPtr.Zero, 
                                                                      ref prompt, dwFlags, ref outputData); 
                    safeOutputDataHandle.SetDataHandle(outputData.pbData);
                } 

                if (!success || outputData.pbData == IntPtr.Zero) {
                    outputData.pbData = IntPtr.Zero;
                    Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error()); 
                }
                byte[] buf = new byte[outputData.cbData]; 
                Marshal.Copy(outputData.pbData, buf, 0, buf.Length); 
                return Encoding.Unicode.GetString(buf);
            } finally { 
                if (!(safeOutputDataHandle == null || safeOutputDataHandle.IsInvalid)) {
                    safeOutputDataHandle.Dispose();
                    outputData.pbData = IntPtr.Zero;
                } 
                if (!(safeEntDataHandle == null || safeEntDataHandle.IsInvalid)) {
                    safeEntDataHandle.Dispose(); 
                    entData.pbData = IntPtr.Zero; 
                }
                if (!(safeInputDataHandle == null || safeInputDataHandle.IsInvalid)) { 
                    safeInputDataHandle.Dispose();
                    inputData.pbData = IntPtr.Zero;
                }
            } 
        }
 
        public bool     UseMachineProtection   { get { return _UseMachineProtection; }} 
        //private virtual string   KeyEntropy    { get { return _KeyEntropy; } }
 
        public override void Initialize(string name, NameValueCollection configurationValues)
        {
            base.Initialize(name, configurationValues);
            _UseMachineProtection = GetBooleanValue(configurationValues, "useMachineProtection", true); 
            _KeyEntropy = configurationValues["keyEntropy"];
            configurationValues.Remove("keyEntropy"); 
            if (configurationValues.Count > 0) 
                throw new ConfigurationErrorsException(SR.GetString(SR.Unrecognized_initialization_value, configurationValues.GetKey(0)));
        } 

        private const int CRYPTPROTECT_UI_FORBIDDEN = 0x1;
        private const int CRYPTPROTECT_LOCAL_MACHINE = 0x4;
        private bool   _UseMachineProtection = true; 
        private string  _KeyEntropy;
 
        private static XmlNode TraverseToChild(XmlNode node, string name, bool onlyChild) 
        {
            foreach (XmlNode child in node.ChildNodes) 
            {
                if (child.NodeType != XmlNodeType.Element)
                    continue;
 
                if (child.Name == name)
                    return child; // found it! 
 
                if (onlyChild)
                    return null; 
            }

            return null;
        } 

        private static DATA_BLOB PrepareDataBlob(byte[] buf) 
        { 
            if (buf == null)
                buf = new byte[0]; 
            DATA_BLOB db = new DATA_BLOB();
            db.cbData = buf.Length;
            db.pbData = Marshal.AllocHGlobal(db.cbData);
            Marshal.Copy(buf, 0, db.pbData, db.cbData); 
            return db;
        } 
        private static DATA_BLOB PrepareDataBlob(string s) 
        {
            return PrepareDataBlob((s != null) ? Encoding.Unicode.GetBytes(s) : new byte[0]); 
        }
        private static CRYPTPROTECT_PROMPTSTRUCT PreparePromptStructure()
        {
            CRYPTPROTECT_PROMPTSTRUCT cps = new CRYPTPROTECT_PROMPTSTRUCT(); 
            cps.cbSize = Marshal.SizeOf(typeof(CRYPTPROTECT_PROMPTSTRUCT));
            cps.dwPromptFlags = 0; 
            cps.hwndApp = IntPtr.Zero; 
            cps.szPrompt = null;
            return cps; 
        }
        private static bool GetBooleanValue(NameValueCollection configurationValues, string valueName, bool defaultValue) {
            string s = configurationValues[valueName];
            if (s == null) 
                return defaultValue;
            configurationValues.Remove(valueName); 
            if (s == "true") 
                return true;
            if (s == "false") 
                return false;
            throw new ConfigurationErrorsException(SR.GetString(SR.Config_invalid_boolean_attribute, valueName));
        }
    } 

} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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