Prompt for passphrase if needed.

src/protocols/ssh/client.c

@@ -150,26 +150,10 @@ int guac_client_init(guac_client* client, int argc, char** argv) {
     strcpy(client_data->password,  argv[IDX_PASSWORD]);
 
 #ifdef ENABLE_SSH_PUBLIC_KEY
-
+    /* Init public key auth information */
     client_data->key = NULL;
-
+    strcpy(client_data->key_base64,     argv[IDX_PRIVATE_KEY]);
-    /* Read private key, if given */
+    strcpy(client_data->key_passphrase, argv[IDX_PASSPHRASE]);
-    if (argv[IDX_PRIVATE_KEY][0] != 0) {
-
-        /* Pull parameters */
-        const char* private_key = argv[IDX_PRIVATE_KEY];
-        const char* passphrase = argv[IDX_PASSPHRASE];
-        if (passphrase[0] == 0)
-            passphrase = NULL;
-
-        /* Read key */
-        if (ssh_pki_import_privkey_base64(private_key, passphrase,
-                NULL, NULL, &client_data->key) == SSH_OK)
-            guac_client_log_info(client, "Auth key successfully imported.");
-        else
-            guac_client_log_error(client, "Auth key import failed.");
-
-    }
 #endif
 
     /* Read font name */

src/protocols/ssh/client.h

@@ -73,6 +73,16 @@ typedef struct ssh_guac_client_data {
     char password[1024];
 
 #ifdef ENABLE_SSH_PUBLIC_KEY
+    /**
+     * The private key, encoded as base64.
+     */
+    char key_base64[4096];
+
+    /**
+     * The password to use to decrypt the given private key.
+     */
+    char key_passphrase[1024];
+
     /**
      * The private key to use for authentication, if any.
      */

src/protocols/ssh/ssh_client.c

@@ -153,15 +153,31 @@ static ssh_session __guac_ssh_create_session(guac_client* client) {
         return NULL;
     }
 
-    /* Authenticate */
+#ifdef ENABLE_SSH_PUBLIC_KEY
-    if (ssh_userauth_password(session, NULL, client_data->password)
+    /* Authenticate with key if available */
-            != SSH_AUTH_SUCCESS) {
+    if (client_data->key != NULL) {
-        guac_client_log_error(client, "Authentication failed: %s",
+        if (ssh_userauth_publickey(session, NULL, client_data->key)
+                == SSH_AUTH_SUCCESS)
+            return session;
+        else {
+            guac_client_log_error(client,
+                    "Public key authentication failed: %s",
                     ssh_get_error(session));
             return NULL;
         }
+    }
+#endif
 
+    /* Authenticate with password */
+    if (ssh_userauth_password(session, NULL, client_data->password)
+            == SSH_AUTH_SUCCESS)
         return session;
+    else {
+        guac_client_log_error(client,
+                "Password authentication failed: %s",
+                ssh_get_error(session));
+        return NULL;
+    }
 
 }
 
@@ -189,11 +205,48 @@ void* ssh_client_thread(void* data) {
     snprintf(name, sizeof(name)-1, "%s@%s", client_data->username, client_data->hostname);
     guac_protocol_send_name(socket, name);
 
-    /* Get password */
+#ifdef ENABLE_SSH_PUBLIC_KEY
-    if (client_data->password[0] == 0 &&
+    /* If key specified, import */
-            prompt(client, "Password: ", client_data->password, sizeof(client_data->password), false) == NULL)
+    if (client_data->key_base64[0] != 0) {
-        return NULL;
 
+        /* Attempt to read key without passphrase */
+        if (ssh_pki_import_privkey_base64(client_data->key_base64, NULL,
+                NULL, NULL, &client_data->key) == SSH_OK)
+            guac_client_log_info(client, "Auth key successfully imported.");
+
+        /* On failure, attempt with passphrase */
+        else {
+
+            /* Prompt for passphrase if missing */
+            if (client_data->key_passphrase[0] == 0) {
+                if (prompt(client, "Key passphrase: ",
+                            client_data->key_passphrase,
+                            sizeof(client_data->key_passphrase), false) == NULL)
+                    return NULL;
+            }
+
+            /* Import key with passphrase */
+            if (ssh_pki_import_privkey_base64(client_data->key_base64,
+                    client_data->key_passphrase,
+                    NULL, NULL, &client_data->key) != SSH_OK) {
+                guac_client_log_error(client, "Auth key import failed.");
+                return NULL;
+            }
+
+        } /* end decrypt key with passphrase */
+
+    } /* end if key given */
+
+    /* Otherwise, get password if not provided */
+    else if (client_data->password[0] == 0) {
+#else
+    /* Get password if not provided */
+    if (client_data->password[0] == 0) {
+#endif
+        if (prompt(client, "Password: ", client_data->password,
+                sizeof(client_data->password), false) == NULL)
+            return NULL;
+    }
 
     /* Clear screen */
     guac_terminal_write_all(stdout_fd, "\x1B[H\x1B[J", 6);