Coverity: 'Constant' variable guards dead code

1. Remove the default password from the wolfSSH client app main
   function. It isn't set to anything. (It was originally an example
   client option.)
2. Remove handling the default password from the wolfSSH client app's
   user authentication callback.
3. Set the password size directly.
4. Changed a void typecast to WOLFSSH_UNUSED.

Fixes CID: 572898

Author: ejohnstown

apps/wolfssh/common.c

@@ -499,6 +499,8 @@ int ClientUserAuth(byte authType,
 {
     int ret = WOLFSSH_USERAUTH_SUCCESS;
 
+    WOLFSSH_UNUSED(ctx);
+
 #ifdef DEBUG_WOLFSSH
     /* inspect supported types from server */
     printf("Server supports:\n");
@@ -538,37 +540,28 @@ int ClientUserAuth(byte authType,
         ret = WOLFSSH_USERAUTH_SUCCESS;
     }
     else if (authType == WOLFSSH_USERAUTH_PASSWORD) {
-        const char* defaultPassword = (const char*)ctx;
-        word32 passwordSz = 0;
-
-        if (defaultPassword != NULL) {
-            passwordSz = (word32)strlen(defaultPassword);
-            WMEMCPY(userPassword, defaultPassword, passwordSz);
+        printf("Password: ");
+        fflush(stdout);
+        ClientSetEcho(0);
+        if (fgets((char*)userPassword, sizeof(userPassword), stdin) == NULL) {
+            fprintf(stderr, "Getting password failed.\n");
+            ret = WOLFSSH_USERAUTH_FAILURE;
         }
         else {
-            printf("Password: ");
-            fflush(stdout);
-            ClientSetEcho(0);
-            if (fgets((char*)userPassword, sizeof(userPassword), stdin) == NULL) {
-                fprintf(stderr, "Getting password failed.\n");
-                ret = WOLFSSH_USERAUTH_FAILURE;
-            }
-            else {
-                char* c = strpbrk((char*)userPassword, "\r\n");
-                if (c != NULL)
-                    *c = '\0';
-            }
-            passwordSz = (word32)strlen((const char*)userPassword);
-            ClientSetEcho(1);
-            #ifdef USE_WINDOWS_API
-                printf("\r\n");
-            #endif
-            fflush(stdout);
+            char* c = strpbrk((char*)userPassword, "\r\n");
+            if (c != NULL)
+                *c = '\0';
         }
+        ClientSetEcho(1);
+        #ifdef USE_WINDOWS_API
+            printf("\r\n");
+        #endif
+        fflush(stdout);
 
         if (ret == WOLFSSH_USERAUTH_SUCCESS) {
             authData->sf.password.password = userPassword;
-            authData->sf.password.passwordSz = passwordSz;
+            authData->sf.password.passwordSz =
+                (word32)strlen((const char*)userPassword);
         }
     }
 
@@ -743,7 +736,7 @@ int ClientLoadCA(WOLFSSH_CTX* ctx, const char* caCert)
             WFREE(der, NULL, 0);
         }
     #else
-        (void)ctx;
+        WOLFSSH_UNUSED(ctx);
         fprintf(stderr, "Support for certificates not compiled in.");
         ret = WS_NOT_COMPILED;
     #endif

apps/wolfssh/wolfssh.c

@@ -900,7 +900,6 @@ static THREAD_RETURN WOLFSSH_THREAD wolfSSH_Client(void* args)
     SOCKADDR_IN_T clientAddr;
     socklen_t clientAddrSz = sizeof(clientAddr);
     int ret = 0;
-    const char* password = NULL;
     byte keepOpen = 1;
 #ifdef USE_WINDOWS_API
     byte rawMode = 0;
@@ -976,9 +975,6 @@ static THREAD_RETURN WOLFSSH_THREAD wolfSSH_Client(void* args)
     wolfSSH_SetGlobalReqCtx(ssh, &ssh); /* dummy ctx */
 #endif
 
-    if (password != NULL)
-        wolfSSH_SetUserAuthCtx(ssh, (void*)password);
-
 #ifdef WOLFSSH_AGENT
     if (useAgent) {
         WMEMSET(&agentCbCtx, 0, sizeof(agentCbCtx));