Fixed race condition with digidoc initialize/terminate

src/WebEid.AspNetCore.Example/Controllers/Api/AuthController.cs

@@ -47,6 +47,10 @@ await HttpContext.SignInAsync(
                 CookieAuthenticationDefaults.AuthenticationScheme,
                 new ClaimsPrincipal(claimsIdentity),
                 authProperties);
+
+            // Assign a unique ID within the session to enable the use of a unique temporary container name across successive requests.
+            // A unique temporary container name is required to facilitate simultaneous signing from multiple browsers.
+            SetUniqueIdInSession();
         }
 
         [HttpGet]

src/WebEid.AspNetCore.Example/Controllers/Api/BaseController.cs

@@ -1,21 +1,31 @@
 namespace WebEid.AspNetCore.Example.Controllers.Api
 {
-    using System.Security;
-    using System.Security.Claims;
+    using System;
+    using Microsoft.AspNetCore.Http;
     using Microsoft.AspNetCore.Mvc;
 
     public abstract class BaseController : ControllerBase
     {
+        const string uniqueIdKey = "UniqueId";
+
         protected void RemoveUserContainerFile()
         {
             System.IO.File.Delete(GetUserContainerName());
         }
 
+        protected void SetUniqueIdInSession() 
+        {
+            HttpContext.Session.SetString(uniqueIdKey, Guid.NewGuid().ToString());
+        }
+
+        private string GetUniqueIdFromSession() 
+        {
+            return HttpContext.Session.GetString(uniqueIdKey);
+        }
+
         protected string GetUserContainerName()
         {
-            var identity = (ClaimsIdentity)this.HttpContext.User?.Identity ??
-                           throw new SecurityException("User is not logged in");
-            return identity.GetIdCode();
+            return $"container_{GetUniqueIdFromSession()}";
         }
     }
 }

src/WebEid.AspNetCore.Example/Controllers/Api/SignController.cs

@@ -3,7 +3,6 @@
     using System;
     using System.Security.Claims;
     using System.Threading.Tasks;
-    using Microsoft.AspNetCore.Authorization;
     using Microsoft.AspNetCore.Mvc;
     using Microsoft.Extensions.Logging;
     using Services;

src/WebEid.AspNetCore.Example/Signing/SigningService.cs

@@ -11,16 +11,23 @@
     using Microsoft.Extensions.Logging;
     using WebEid.Security.Util;
 
-    public class SigningService
+    public class SigningService : IDisposable
     {
         private static readonly string FileToSign = Path.Combine("wwwroot", "files", "example-for-signing.txt");
         private readonly DigiDocConfiguration configuration;
         private readonly ILogger logger;
+        private bool _disposedValue;
 
         public SigningService(DigiDocConfiguration configuration, ILogger logger)
         {
             this.configuration = configuration;
             this.logger = logger;
+
+            // The current implementation of the static DigiDoc library assumes that SigningService is used as a singleton.
+            // In the ASP.NET Core application, we initialize it using the AddSingleton method in Startup.cs.
+            // The DigiDoc library is initialized in the constructor and terminated in Dispose.
+            configuration.Initialize();
+            digidoc.initialize("WebEidExample");
         }
 
         public DigestDto PrepareContainer(CertificateDto data, ClaimsIdentity identity, string tempContainerName)
@@ -32,48 +39,29 @@ public DigestDto PrepareContainer(CertificateDto data, ClaimsIdentity identity,
                     "Authenticated subject ID code differs from signing certificate subject ID code");
             }
 
-            configuration.Initialize();
-            digidoc.initialize("WebEidExample");
-            try
-            {
-                this.logger?.LogDebug("Creating container file: '{0}'", tempContainerName);
-                Container container = Container.create(tempContainerName);
-                container.addDataFile(FileToSign, "application/octet-stream");
-                logger?.LogInformation("Preparing container for signing for file '{0}'", tempContainerName);
-                var signature =
-                    container.prepareWebSignature(certificate.Export(X509ContentType.Cert), "time-stamp");
-                var hashFunction = GetSupportedHashAlgorithm(data.SupportedSignatureAlgorithms, signature.signatureMethod());
-                container.save();
-                return new DigestDto
-                {
-                    Hash = Convert.ToBase64String(signature.dataToSign()),
-                    HashFunction = hashFunction
-                };
-            }
-            finally
+            this.logger?.LogDebug("Creating container file: '{0}'", tempContainerName);
+            Container container = Container.create(tempContainerName);
+            container.addDataFile(FileToSign, "application/octet-stream");
+            logger?.LogInformation("Preparing container for signing for file '{0}'", tempContainerName);
+            var signature =
+                container.prepareWebSignature(certificate.Export(X509ContentType.Cert), "time-stamp");
+            var hashFunction = GetSupportedHashAlgorithm(data.SupportedSignatureAlgorithms, signature.signatureMethod());
+            container.save();
+            return new DigestDto
             {
-                digidoc.terminate();
-            }
+                Hash = Convert.ToBase64String(signature.dataToSign()),
+                HashFunction = hashFunction
+            };
         }
 
-
         public void SignContainer(SignatureDto signatureDto, string tempContainerName)
         {
-            configuration.Initialize();
-            digidoc.initialize("WebEidExample");
-            try
-            {
-                var container = Container.open(tempContainerName);
-                var signatureBytes = Convert.FromBase64String(signatureDto.Signature);
-                var signature = container.signatures().First(); // Container must have one signature as it was added in PrepareContainer
-                signature.setSignatureValue(signatureBytes);
-                signature.extendSignatureProfile("BES/time-stamp");
-                container.save();
-            }
-            finally
-            {
-                digidoc.terminate();
-            }
+            var container = Container.open(tempContainerName);
+            var signatureBytes = Convert.FromBase64String(signatureDto.Signature);
+            var signature = container.signatures().First(); // Container must have one signature as it was added in PrepareContainer
+            signature.setSignatureValue(signatureBytes);
+            signature.extendSignatureProfile("BES/time-stamp");
+            container.save();
         }
 
         private static string GetSupportedHashAlgorithm(IList<SignatureAlgorithmDto> supportedSignatureAlgorithms, string signatureMethod)
@@ -86,22 +74,44 @@ private static string GetSupportedHashAlgorithm(IList<SignatureAlgorithmDto> sup
             throw new ArgumentException("Supported signature algorithm not found");
         }
 
-        private static bool FragmentEquals(string framgent, SignatureAlgorithmDto signatureAlgorithm) =>
+        private static bool FragmentEquals(string fragment, SignatureAlgorithmDto signatureAlgorithm) =>
             signatureAlgorithm switch
             {
-                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-224" } => framgent == "#ecdsa-sha224",
-                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-256" } => framgent == "#ecdsa-sha256",
-                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-384" } => framgent == "#ecdsa-sha384",
-                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-512" } => framgent == "#ecdsa-sha512",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-224" } => framgent == "#rsa-sha224",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-256" } => framgent == "#rsa-sha256",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-384" } => framgent == "#rsa-sha384",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-512" } => framgent == "#rsa-sha512",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-224" } => framgent == "#sha224-rsa-MGF1",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-256" } => framgent == "#sha256-rsa-MGF1",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-384" } => framgent == "#sha384-rsa-MGF1",
-                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-512" } => framgent == "#sha512-rsa-MGF1",
+                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-224" } => fragment == "#ecdsa-sha224",
+                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-256" } => fragment == "#ecdsa-sha256",
+                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-384" } => fragment == "#ecdsa-sha384",
+                { CryptoAlgorithm: "ECC", PaddingScheme: "NONE", HashFunction: "SHA-512" } => fragment == "#ecdsa-sha512",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-224" } => fragment == "#rsa-sha224",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-256" } => fragment == "#rsa-sha256",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-384" } => fragment == "#rsa-sha384",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PKCS1.5", HashFunction: "SHA-512" } => fragment == "#rsa-sha512",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-224" } => fragment == "#sha224-rsa-MGF1",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-256" } => fragment == "#sha256-rsa-MGF1",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-384" } => fragment == "#sha384-rsa-MGF1",
+                { CryptoAlgorithm: "RSA", PaddingScheme: "PSS", HashFunction: "SHA-512" } => fragment == "#sha512-rsa-MGF1",
                 _ => false
             };
+
+        ~SigningService() => Dispose(false);
+
+        public void Dispose()
+        {
+            Dispose(true);
+            GC.SuppressFinalize(this);
+        }
+
+        private void Dispose(bool disposing)
+        {
+            if (!_disposedValue)
+            {
+                if (disposing)
+                {
+                    // You can release managed resources here if needed.
+                }
+
+                digidoc.terminate();
+                _disposedValue = true;
+            }
+        }
     }
 }