Feat(Rules): Allow message validation expression #165 (#1377)

Rnwood.Smtp4dev/ApiModel/Server.cs

@@ -32,6 +32,7 @@ public class Server
         public string CredentialsValidationExpression { get; set; }
         public bool SecureConnectionRequired { get; set; }
         public string RecipientValidationExpression { get; set; }
+        public string MessageValidationExpression { get; set; }
     }
 
 }

Rnwood.Smtp4dev/ApiModel/Session.cs

@@ -12,13 +12,15 @@ public Session(DbModel.Session dbSession)
         {
             this.Id = dbSession.Id;
             this.Error = dbSession.SessionError;
-            this.ErrorType = dbSession.SessionErrorType.ToString();
+            this.ErrorType = dbSession.SessionErrorType?.ToString();
+            this.StartDate = dbSession.StartDate;
         }
 
 
         public Guid Id { get; private set; }
 
         public string ErrorType { get; private set; }
+        public DateTime StartDate { get; }
         public string Error { get; private set; }
 
 

Rnwood.Smtp4dev/ClientApp/src/ApiClient/Server.ts

@@ -5,7 +5,7 @@ export default class Server {
 
     constructor(isRunning: boolean, exception: string, portNumber: number, hostName: string, allowRemoteConnections: boolean, numberOfMessagesToKeep: number, numberOfSessionsToKeep: number, relayOptions: ServerRelayOptions, imapPortNumber: number, settingsAreEditable: boolean, disableMessageSanitisation: boolean, automaticRelayExpression: string, tlsMode: string,     credentialsValidationExpression: string,
     authenticationRequired: boolean,
-    secureConnectionRequired: boolean, recipientValidationExpression: string) {
+    secureConnectionRequired: boolean, recipientValidationExpression: string, messageValidationExpression : string) {
 
         this.isRunning = isRunning; 
         this.exception = exception; 
@@ -24,6 +24,7 @@ export default class Server {
         this.authenticationRequired = authenticationRequired;
         this.secureConnectionRequired = secureConnectionRequired;
         this.recipientValidationExpression = recipientValidationExpression;
+        this.messageValidationExpression = messageValidationExpression;
     }
 
 
@@ -44,4 +45,5 @@ export default class Server {
     authenticationRequired: boolean;
     secureConnectionRequired: boolean;
     recipientValidationExpression: string;
+    messageValidationExpression: string;
 }

Rnwood.Smtp4dev/ClientApp/src/components/settingsdialog.vue

@@ -43,6 +43,10 @@
                       <el-form-item label="Recipient validation expression (see comments in appsettings.json)" prop="server.recipientValidationExpression">
                         <el-input v-model="server.recipientValidationExpression" />
                       </el-form-item>
+
+                      <el-form-item label="Message validation expression (see comments in appsettings.json)" prop="server.messageValidationExpression">
+                        <el-input v-model="server.messageValidationExpression" />
+                      </el-form-item>
                     </el-tab-pane>
 
 

Rnwood.Smtp4dev/Controllers/ServerController.cs

@@ -68,7 +68,8 @@ public ApiModel.Server GetServer()
                 AuthenticationRequired = serverOptions.CurrentValue.AuthenticationRequired,
                 SecureConnectionRequired = serverOptions.CurrentValue.SecureConnectionRequired,
                 CredentialsValidationExpression = serverOptions.CurrentValue.CredentialsValidationExpression,
-                RecipientValidationExpression = serverOptions.CurrentValue.RecipientValidationExpression
+                RecipientValidationExpression = serverOptions.CurrentValue.RecipientValidationExpression,
+                MessageValidationExpression = serverOptions.CurrentValue.MessageValidationExpression
             };
         }
 
@@ -101,6 +102,7 @@ public ActionResult UpdateServer(ApiModel.Server serverUpdate)
             newSettings.SecureConnectionRequired = serverUpdate.SecureConnectionRequired;
             newSettings.CredentialsValidationExpression = serverUpdate.CredentialsValidationExpression;
             newSettings.RecipientValidationExpression = serverUpdate.RecipientValidationExpression;
+            newSettings.MessageValidationExpression = serverUpdate.MessageValidationExpression;
 
             newRelaySettings.SmtpServer = serverUpdate.RelayOptions.SmtpServer;
             newRelaySettings.SmtpPort = serverUpdate.RelayOptions.SmtpPort;

Rnwood.Smtp4dev/Rnwood.Smtp4dev.csproj

@@ -32,6 +32,8 @@
     <PackageReference Include="Jint" Version="3.0.1" />
     <PackageReference Include="MailKit" Version="4.4.0" />
     <PackageReference Include="Microsoft.AspNetCore.Hosting.WindowsServices" Version="8.0.4" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Common" Version="4.9.2" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.9.2" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Analyzers" Version="8.0.4" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="8.0.4">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
@@ -44,6 +46,7 @@
     <PackageReference Include="Mono.Options" Version="6.12.0.148" />
     <PackageReference Include="NSwag.AspNetCore" Version="14.0.7" />
     <PackageReference Include="Rnwood.LumiSoft.Net" Version="1.0.0" />
+    <PackageReference Include="Rnwood.SmtpServer" Version="3.1.0-ci0868" />
 
 
     <PackageReference Include="Serilog" Version="3.1.1" />
@@ -54,15 +57,10 @@
     <PackageReference Include="System.Linq.Dynamic.Core" Version="1.3.10" />
     <PackageReference Include="System.Reactive" Version="6.0.0" />
     <PackageReference Include="VueCliMiddleware" Version="6.0.0" />
-  </ItemGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Rnwood.SmtpServer" Version="3.1.0-ci0843" />
-  </ItemGroup>
+    </ItemGroup>
 
   <ItemGroup>
-    <DotNetCliToolReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Tools"
-      Version="2.1.0-preview1-final" />
+    <DotNetCliToolReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Tools" Version="2.1.0-preview1-final" />
   </ItemGroup>
 
   <ItemGroup>
@@ -143,11 +141,9 @@
     <NpmInputs Include="ClientApp\package.json" />
   </ItemGroup>
 
-  <Target Name="NpmInstall" AfterTargets="Build" Inputs="@(NpmInputs)"
-    Outputs="ClientApp\node_modules\.installedtimestamp" Condition="'$(SkipClientApp)'!='true'">
+  <Target Name="NpmInstall" AfterTargets="Build" Inputs="@(NpmInputs)" Outputs="ClientApp\node_modules\.installedtimestamp" Condition="'$(SkipClientApp)'!='true'">
     <Message Importance="high" Text="Performing npm install..." />
-    <Exec Command="npm install --no-progress" WorkingDirectory="ClientApp"
-      CustomErrorRegularExpression="^npm ERR!.*" />
+    <Exec Command="npm install --no-progress" WorkingDirectory="ClientApp" CustomErrorRegularExpression="^npm ERR!.*" />
     <Touch Files="ClientApp\node_modules\.installedtimestamp" AlwaysCreate="true" />
   </Target>
 
@@ -184,22 +180,18 @@
     <TypeScriptCompile Include="ClientApp\src\ApiClient\ServerRelayOptions.ts" />
   </ItemGroup>
 
-  <Target Name="DebugRunNpm" AfterTargets="Build" Inputs="@(ClientApp)"
-    Outputs="wwwroot\.buildtimestamp" Condition="'$(SkipClientApp)'!='true'">
+  <Target Name="DebugRunNpm" AfterTargets="Build" Inputs="@(ClientApp)" Outputs="wwwroot\.buildtimestamp" Condition="'$(SkipClientApp)'!='true'">
 
     <!-- Ensure Node.js is installed -->
     <Exec Command="node --version" ContinueOnError="true">
       <Output TaskParameter="ExitCode" PropertyName="ErrorCode" />
     </Exec>
-    <Error Condition="'$(ErrorCode)' != '0'"
-      Text="Node.js is required to build and run this project. To continue, please install Node.js from https://nodejs.org/, and then restart your command prompt or IDE." />
+    <Error Condition="'$(ErrorCode)' != '0'" Text="Node.js is required to build and run this project. To continue, please install Node.js from https://nodejs.org/, and then restart your command prompt or IDE." />
 
     <Message Importance="high" Text="Performing NPM build..." />
 
-    <Exec Condition=" '$(Configuration)' != 'Release' "
-      Command="npm --prefix ClientApp run-script build:dev" CustomErrorRegularExpression="^ERROR in" />
-    <Exec Condition=" '$(Configuration)' == 'Release' "
-      Command="npm --prefix ClientApp run-script build" CustomErrorRegularExpression="^ERROR in" />
+    <Exec Condition=" '$(Configuration)' != 'Release' " Command="npm --prefix ClientApp run-script build:dev" CustomErrorRegularExpression="^ERROR in" />
+    <Exec Condition=" '$(Configuration)' == 'Release' " Command="npm --prefix ClientApp run-script build" CustomErrorRegularExpression="^ERROR in" />
 
     <Touch Files="wwwroot\.buildtimestamp" AlwaysCreate="true" />
   </Target>
@@ -208,8 +200,7 @@
     <!-- Include the newly-built files in the publish output -->
     <ItemGroup>
       <DistFiles Include="wwwroot\**" />
-      <ResolvedFileToPublish Include="@(DistFiles->'%(FullPath)')"
-        Exclude="@(ResolvedFileToPublish)">
+      <ResolvedFileToPublish Include="@(DistFiles->'%(FullPath)')" Exclude="@(ResolvedFileToPublish)">
         <RelativePath>%(DistFiles.Identity)</RelativePath>
         <CopyToPublishDirectory>PreserveNewest</CopyToPublishDirectory>
       </ResolvedFileToPublish>

Rnwood.Smtp4dev/Server/ScriptingHost.cs

@@ -7,6 +7,7 @@
 using Jint;
 using Jint.Native;
 using Jint.Runtime;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
 using Microsoft.Extensions.Options;
 using Rnwood.Smtp4dev.DbModel;
 using Rnwood.SmtpServer;
@@ -19,7 +20,7 @@ internal class ScriptingHost
 {
     private readonly ILogger log = Log.ForContext<ScriptingHost>();
 
-    
+
 
     private IOptionsMonitor<RelayOptions> relayOptions;
     private IOptionsMonitor<ServerOptions> serverOptions;
@@ -61,6 +62,8 @@ private void ParseScripts(RelayOptions relayOptionsCurrentValue, ServerOptions s
             ref credValidationSource);
         ParseScript("RecipientValidationExpression", serverOptionsCurrentValue.RecipientValidationExpression, ref recipValidationScript,
             ref recipValidationSource);
+        ParseScript("MessageValidationExpression", serverOptionsCurrentValue.MessageValidationExpression, ref messageValidationScript,
+            ref messageValidationSource);
     }
 
     private string shouldRelaySource;
@@ -69,17 +72,21 @@ private void ParseScripts(RelayOptions relayOptionsCurrentValue, ServerOptions s
     private Script credValidationScript;
     private string recipValidationSource;
     private Script recipValidationScript;
-
-
+
+    private string messageValidationSource;
+    private Script messageValidationScript;
+
+    public bool HasValidateMessageExpression { get => this.messageValidationScript != null; }
+
     public IReadOnlyCollection<string> GetAutoRelayRecipients(ApiModel.Message message, string recipient, ApiModel.Session session)
     {
         if (shouldRelayScript == null)
         {
             return Array.Empty<string>();
         }
-        
+
         Engine jsEngine = new Engine();
-        
+
         jsEngine.SetValue("recipient", recipient);
         jsEngine.SetValue("message", message);
         jsEngine.SetValue("session", session);
@@ -91,7 +98,7 @@ public IReadOnlyCollection<string> GetAutoRelayRecipients(ApiModel.Message messa
             List<string> recpients = new List<string>();
             if (result.IsNull())
             {
-                
+
             }
             else if (result.IsString())
             {
@@ -128,15 +135,15 @@ public IReadOnlyCollection<string> GetAutoRelayRecipients(ApiModel.Message messa
 
     }
 
-    public AuthenticationResult ValidateCredentials(Session session, IAuthenticationCredentials credentials)
+    public AuthenticationResult ValidateCredentials(ApiModel.Session session, IAuthenticationCredentials credentials)
     {
         if (credValidationScript == null)
         {
             return AuthenticationResult.Success;
         }
-        
+
         Engine jsEngine = new Engine();
-        
+
         jsEngine.SetValue("credentials", credentials);
         jsEngine.SetValue("session", session);
 
@@ -145,7 +152,7 @@ public AuthenticationResult ValidateCredentials(Session session, IAuthentication
             JsValue result = jsEngine.Evaluate(credValidationScript);
 
             bool success = result.AsBoolean();
-            
+
             log.Information("CredentialValidationExpression: (credentials: {credentials}, session: {session.Id}) => {result} => {success}", credentials,
                 session.Id, result, success);
 
@@ -163,16 +170,16 @@ public AuthenticationResult ValidateCredentials(Session session, IAuthentication
             return AuthenticationResult.TemporaryFailure;
         }
     }
-    
-    public bool ValidateRecipient(Session session, string recipient)
+
+    public bool ValidateRecipient(ApiModel.Session session, string recipient)
     {
         if (recipValidationScript == null)
         {
             return true;
         }
-        
+
         Engine jsEngine = new Engine();
-        
+
         jsEngine.SetValue("recipient", recipient);
         jsEngine.SetValue("session", session);
 
@@ -181,7 +188,7 @@ public bool ValidateRecipient(Session session, string recipient)
             JsValue result = jsEngine.Evaluate(recipValidationScript);
 
             bool success = result.AsBoolean();
-            
+
             log.Information("RecipientValidationExpression: (recipient: {recipient}, session: {session.Id}) => {result} => {success}", recipient,
                 session.Id, result, success);
 
@@ -199,4 +206,60 @@ public bool ValidateRecipient(Session session, string recipient)
             return false;
         }
     }
+
+    internal SmtpResponse ValidateMessage(ApiModel.Message message, ApiModel.Session session)
+    {
+        if (messageValidationScript == null)
+        {
+            return null;
+        }
+
+        Engine jsEngine = new Engine();
+
+        jsEngine.SetValue("message", message);
+        jsEngine.SetValue("session", session);
+        jsEngine.SetValue("error", (Action<int?, string>)((code, message) => throw new SmtpServerException(new SmtpResponse(code ?? (int)StandardSmtpResponseCode.TransactionFailed, message ?? ""))));
+
+        try
+        {
+            JsValue result = jsEngine.Evaluate(messageValidationScript);
+
+            SmtpResponse response;
+
+            if (result.IsNull() || result.IsUndefined())
+            {
+                response = null;
+            }
+            else if (result.IsNumber())
+            {
+                response = new SmtpResponse((int)result.AsNumber(), "Message rejected by MessageValidationExpression");
+            } else if (result.IsString()) {
+                response = new SmtpResponse(StandardSmtpResponseCode.TransactionFailed, result.AsString());
+            }
+            else
+            {
+                response = result.AsBoolean() ? null : new SmtpResponse(StandardSmtpResponseCode.TransactionFailed, "Message rejected by MessageValidationExpression");
+            }
+
+            log.Information("MessageValidationExpression: (message: {message}, session: {session.Id}) => {result} => {success}", message,
+                session.Id, result, response?.Code.ToString() ?? "Success");
+
+            return response;
+
+        }
+        catch (SmtpServerException ex)
+        {
+            return ex.SmtpResponse;
+        }
+        catch (JavaScriptException ex)
+        {
+            log.Error("Error executing MessageValidationExpression : {error}", ex.Error);
+            return new SmtpResponse(StandardSmtpResponseCode.TransactionFailed, "MessageValidationExpression failed");
+        }
+        catch (Exception ex)
+        {
+            log.Error("Error executing MessageValidationExpression : {error}", ex.ToString());
+            return new SmtpResponse(StandardSmtpResponseCode.TransactionFailed, "MessageValidationExpression failed");
+        }
+    }
 }

Rnwood.Smtp4dev/Server/ServerOptions.cs

@@ -35,5 +35,7 @@ public class ServerOptions
         public bool AuthenticationRequired { get; set; } = false;
         public bool SecureConnectionRequired { get; set; } = false;
         public string RecipientValidationExpression { get; set; }
+
+        public string MessageValidationExpression { get; set; }
     }
 }