- Platform specific function to correctly set the path for the certificates;

- Updated all the examples with it;

wrapper/CSharp/wolfSSL-DTLS-PSK-Server/wolfSSL-DTLS-PSK-Server.cs

@@ -78,9 +78,14 @@ public class wolfSSL_DTLS_PSK_Server
         IntPtr ssl;
 
         /* These paths should be changed according to use */
-        string fileCert = @"server-cert.pem";
+        string fileCert = wolfssl.setPath("server-cert.pem");
-        string fileKey = @"server-key.pem";
+        string fileKey = wolfssl.setPath("server-key.pem");
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (fileCert == "" || fileKey == "" || dhparam.Length == 0) {
+            Console.WriteLine("Platform not supported");
+            return;
+        }
 
         wolfssl.psk_delegate psk_cb = new wolfssl.psk_delegate(my_psk_server_cb);
 
@@ -106,6 +111,12 @@ public class wolfSSL_DTLS_PSK_Server
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
 
         if (wolfssl.CTX_use_certificate_file(ctx, fileCert, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
         {

wrapper/CSharp/wolfSSL-DTLS-Server/wolfSSL-DTLS-Server.cs

@@ -58,9 +58,14 @@ public class wolfSSL_DTLS_Server
         IntPtr ssl;
 
         /* These paths should be changed for use */
-        string fileCert = @"server-cert.pem";
+        string fileCert = wolfssl.setPath("server-cert.pem");
-        string fileKey = @"server-key.pem";
+        string fileKey = wolfssl.setPath(@"server-key.pem");
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (fileCert == "" || fileKey == "" || dhparam.Length == 0) {
+            Console.WriteLine("Platform not supported");
+            return;
+        }
 
         StringBuilder buff = new StringBuilder(1024);
         StringBuilder reply = new StringBuilder("Hello, this is the wolfSSL C# wrapper");
@@ -87,6 +92,12 @@ public class wolfSSL_DTLS_Server
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
 
         if (wolfssl.CTX_use_certificate_file(ctx, fileCert, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
         {

wrapper/CSharp/wolfSSL-Example-IOCallbacks/wolfSSL-Example-IOCallbacks.cs

@@ -214,12 +214,17 @@ class wolfSSL_Example_IOCallbacks
         IntPtr ssl;
         Socket fd;
 
-        wolfssl.psk_delegate psk_cb = new wolfssl.psk_delegate(my_psk_server_cb);
         wolfssl.CallbackVerify_delegate verify_cb = new wolfssl.CallbackVerify_delegate(my_verify_cb);
 
         /* These paths should be changed according to use */
-        string fileCert = @"server-cert.pem";
+        string fileCert = wolfssl.setPath("server-cert.pem");
-        string fileKey = @"server-key.pem";
+        string fileKey = wolfssl.setPath("server-key.pem");
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (fileCert == "" || fileKey == "" || dhparam.Length == 0) {
+            Console.WriteLine("Platform not supported");
+            return;
+        }
 
         StringBuilder buff = new StringBuilder(1024);
         StringBuilder reply = new StringBuilder("Hello, this is the wolfSSL C# wrapper");
@@ -242,6 +247,12 @@ class wolfSSL_Example_IOCallbacks
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
         if (wolfssl.CTX_use_certificate_file(ctx, fileCert, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
         {
             Console.WriteLine("Error in setting cert file");

wrapper/CSharp/wolfSSL-TLS-Client/wolfSSL-TLS-Client.cs

@@ -77,19 +77,6 @@ public class wolfSSL_TLS_Client
         return -1;
     }
 
-    public static string setPath() {
-        if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
-        {
-            return @"../../certs/ca-cert.pem";
-        } else if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) 
-        {
-            return @"../../../../certs/ca-cert.pem";
-        } else 
-        {
-            return "";
-        }
-    }
-
     public static void Main(string[] args)
     {
         IntPtr ctx;
@@ -98,14 +85,14 @@ public class wolfSSL_TLS_Client
         IntPtr sniHostName;
 
         /* These paths should be changed for use */
-        string caCert = setPath();
+        string caCert = wolfssl.setPath("ca-cert.pem");
-        if (caCert == "") {
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (caCert == "" || dhparam.Length == 0) {
             Console.WriteLine("Platform not supported.");
             return; 
         }
 
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
-
         StringBuilder buff = new StringBuilder(1024);
         StringBuilder reply = new StringBuilder("Hello, this is the wolfSSL C# wrapper");
 
@@ -131,6 +118,12 @@ public class wolfSSL_TLS_Client
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
         if (wolfssl.CTX_load_verify_locations(ctx, caCert, null)
             != wolfssl.SUCCESS)
         {

wrapper/CSharp/wolfSSL-TLS-PSK-Client/wolfSSL-TLS-PSK-Client.cs

@@ -82,7 +82,11 @@ public class wolfSSL_TLS_PSK_Client
 
         wolfssl.psk_client_delegate psk_cb = new wolfssl.psk_client_delegate(my_psk_client_cb);
 
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+        if (dhparam.Length == 0) {
+            Console.WriteLine("Platform not supported");
+            return;
+        }
 
         StringBuilder buff = new StringBuilder(1024);
         StringBuilder reply = new StringBuilder("Hello, this is the wolfSSL C# client psk wrapper");
@@ -157,6 +161,12 @@ public class wolfSSL_TLS_PSK_Client
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
         wolfssl.SetTmpDH_file(ssl, dhparam, wolfssl.SSL_FILETYPE_PEM);
 
         if (wolfssl.connect(ssl) != wolfssl.SUCCESS)

wrapper/CSharp/wolfSSL-TLS-PSK-Server/wolfSSL-TLS-PSK-Server.cs

@@ -80,9 +80,14 @@ public class wolfSSL_TLS_PSK_Server
         wolfssl.psk_delegate psk_cb = new wolfssl.psk_delegate(my_psk_server_cb);
 
         /* These paths should be changed according to use */
-        string fileCert = @"server-cert.pem";
+        string fileCert = wolfssl.setPath("server-cert.pem");
-        string fileKey = @"server-key.pem";
+        string fileKey = wolfssl.setPath("server-key.pem");
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (fileCert == "" || fileKey == "" || dhparam.Length == 0) {
+            Console.WriteLine("Platform not supported");
+            return;
+        }
 
         StringBuilder buff = new StringBuilder(1024);
         StringBuilder reply = new StringBuilder("Hello, this is the wolfSSL C# wrapper");
@@ -105,6 +110,12 @@ public class wolfSSL_TLS_PSK_Server
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
         if (wolfssl.CTX_use_certificate_file(ctx, fileCert, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
         {
             Console.WriteLine("Error in setting cert file");

wrapper/CSharp/wolfSSL-TLS-Server/wolfSSL-TLS-Server.cs

@@ -80,19 +80,6 @@ public class wolfSSL_TLS_CSHarp
         return 0;
     }
 
-    public static string setPath(string file) {
-        if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
-        {
-            return @"../../certs/" + file;
-        } else if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
-        {
-            return @"../../../../certs/" + file;
-        } else
-        {
-            return "";
-        }
-    }
-
     public static void Main(string[] args)
     {
         IntPtr ctx;
@@ -101,15 +88,15 @@ public class wolfSSL_TLS_CSHarp
         IntPtr arg_sni;
 
         /* These paths should be changed for use */
-        string fileCert = setPath("server-cert.pem");
+        string fileCert = wolfssl.setPath("server-cert.pem");
-        string fileKey = setPath("server-key.pem");
+        string fileKey = wolfssl.setPath("server-key.pem");
-        if (fileCert == "" || fileKey == "") {
+        StringBuilder dh2048Pem = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (fileCert == "" || fileKey == "" || dh2048Pem.Length == 0) {
             Console.WriteLine("Platform not supported.");
             return;
         }
 
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
-
         StringBuilder buff = new StringBuilder(1024);
         StringBuilder reply = new StringBuilder("Hello, this is the wolfSSL C# wrapper");
 
@@ -134,6 +121,12 @@ public class wolfSSL_TLS_CSHarp
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
         if (wolfssl.CTX_use_certificate_file(ctx, fileCert, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
         {
             Console.WriteLine("Error in setting cert file");
@@ -197,7 +190,14 @@ public class wolfSSL_TLS_CSHarp
             return;
         }
 
-        wolfssl.SetTmpDH_file(ssl, dhparam, wolfssl.SSL_FILETYPE_PEM);
+        if (wolfssl.SetTmpDH_file(ssl, dh2048Pem, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
+        {
+            Console.WriteLine("Error in setting dh2048Pem");
+            Console.WriteLine(wolfssl.get_error(ssl));
+            tcp.Stop();
+            clean(ssl, ctx);
+            return;
+        }
 
         if (wolfssl.accept(ssl) != wolfssl.SUCCESS)
         {

wrapper/CSharp/wolfSSL-TLS-ServerThreaded/wolfSSL-TLS-ServerThreaded.cs

@@ -116,9 +116,14 @@ public class wolfSSL_TLS_ServerThreaded
         IntPtr ctx;
 
         /* These paths should be changed for use */
-        string fileCert = @"server-cert.pem";
+        string fileCert = wolfssl.setPath("server-cert.pem");
-        string fileKey = @"server-key.pem";
+        string fileKey = wolfssl.setPath("server-key.pem");
-        StringBuilder dhparam = new StringBuilder("dh2048.pem");
+        StringBuilder dhparam = new StringBuilder(wolfssl.setPath("dh2048.pem"));
+
+        if (fileCert == "" || fileKey == "" || dhparam.Length == 0) {
+            Console.WriteLine("Platform not supported");
+            return;
+        }
 
         /* example of function used for setting logging */
         wolfssl.SetLogging(standard_log);
@@ -140,6 +145,12 @@ public class wolfSSL_TLS_ServerThreaded
             return;
         }
 
+        if (!File.Exists(dhparam.ToString())) {
+            Console.WriteLine("Could not find dh file");
+            wolfssl.CTX_free(ctx);
+            return;
+        }
+
         if (wolfssl.CTX_use_certificate_file(ctx, fileCert, wolfssl.SSL_FILETYPE_PEM) != wolfssl.SUCCESS)
         {
             Console.WriteLine("Error in setting cert file");

wrapper/CSharp/wolfSSL_CSharp/wolfSSL.cs

@@ -485,6 +485,26 @@ namespace wolfSSL.CSharp {
             }
         }
 
+        /// <summary>
+        /// Utility function used to access the certificates
+        /// based on the platform.
+        /// <returns>return the platform specific path to the certificate</returns>
+        /// </summary>
+        public static string setPath(string file) {
+            if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
+            {
+                Console.WriteLine("Linux - " + file);
+                return @"../../certs/" + file;
+            } else if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+            {
+                Console.WriteLine("Windows - " + file);
+                return @"../../../../certs/" + file;
+            } else
+            {
+                return "";
+            }
+        }
+
 
         /// <summary>
         /// Call back to allow receiving TLS information