GUACAMOLE-474: Implement logic to disable file transfers in each protocol.

src/common-ssh/common-ssh/sftp.h

@@ -70,6 +70,16 @@ typedef struct guac_common_ssh_sftp_filesystem {
      */
     char upload_path[GUAC_COMMON_SSH_SFTP_MAX_PATH];
     
+    /**
+     * If downloads from SFTP to the local browser should be disabled.
+     */
+    int disable_download;
+    
+    /**
+     * If uploads from the local browser to SFTP should be disabled.
+     */
+    int disable_upload;
+
 } guac_common_ssh_sftp_filesystem;
 
 /**
@@ -123,12 +133,19 @@ typedef struct guac_common_ssh_sftp_ls_state {
  *     to a user, or NULL to automatically generate a name from the provided
  *     root_path.
  * 
+ * @param disable_download
+ *     Whether downloads from the SFTP share to the local browser should be
+ *     disabled.
+ * 
+ * @param disable_upload
+ *     Whether uploads from the local browser to SFTP should be disabled.
+ *
  * @return
  *     A new SFTP filesystem object, not yet exposed to users.
  */
 guac_common_ssh_sftp_filesystem* guac_common_ssh_create_sftp_filesystem(
         guac_common_ssh_session* session, const char* root_path,
-        const char* name);
+        const char* name, int disable_download, int disable_upload);
 
 /**
  * Destroys the given filesystem object, disconnecting from SFTP and freeing

src/common-ssh/sftp.c

@@ -429,7 +429,7 @@ int guac_common_ssh_sftp_handle_file_stream(
 
 /**
  * Handler for ack messages which continue an outbound SFTP data transfer
- * (download), signalling the current status and requesting additional data.
+ * (download), signaling the current status and requesting additional data.
  * The data associated with the given stream is expected to be a pointer to an
  * open LIBSSH2_SFTP_HANDLE for the file from which the data is to be read.
  *
@@ -787,6 +787,13 @@ static int guac_common_ssh_sftp_get_handler(guac_user* user,
     /* Otherwise, send file contents */
     else {
 
+        /* If downloads are disabled, log and return. */
+        if (filesystem->disable_download) {
+            guac_user_log(user, GUAC_LOG_INFO,
+                    "File downloads have been disabled.");
+            return 0;
+        }
+        
         /* Open as normal file */
         LIBSSH2_SFTP_HANDLE* file = libssh2_sftp_open(sftp, fullpath,
             LIBSSH2_FXF_READ, 0);
@@ -903,7 +910,11 @@ guac_object* guac_common_ssh_alloc_sftp_filesystem_object(
     /* Init filesystem */
     guac_object* fs_object = guac_user_alloc_object(user);
     fs_object->get_handler = guac_common_ssh_sftp_get_handler;
+    
+    /* Only handle uploads if not disabled. */
+    if (!filesystem->disable_upload)
         fs_object->put_handler = guac_common_ssh_sftp_put_handler;
+    
     fs_object->data = filesystem;
 
     /* Send filesystem to user */
@@ -916,7 +927,7 @@ guac_object* guac_common_ssh_alloc_sftp_filesystem_object(
 
 guac_common_ssh_sftp_filesystem* guac_common_ssh_create_sftp_filesystem(
         guac_common_ssh_session* session, const char* root_path,
-        const char* name) {
+        const char* name, int disable_download, int disable_upload) {
 
     /* Request SFTP */
     LIBSSH2_SFTP* sftp_session = libssh2_sftp_init(session->session);
@@ -931,6 +942,10 @@ guac_common_ssh_sftp_filesystem* guac_common_ssh_create_sftp_filesystem(
     filesystem->ssh_session = session;
     filesystem->sftp_session = sftp_session;
     
+    /* Copy over disable flags */
+    filesystem->disable_download = disable_download;
+    filesystem->disable_upload = disable_upload;
+
     /* Normalize and store the provided root path */
     if (!guac_common_ssh_sftp_normalize_path(filesystem->root_path,
                 root_path)) {

src/protocols/rdp/channels/rdpdr/rdpdr-fs-messages.c

@@ -221,8 +221,9 @@ void guac_rdpdr_fs_process_close(guac_rdp_common_svc* svc,
         return;
 
     /* If file was written to, and it's in the \Download folder, start stream */
-    if (file->bytes_written > 0 &&
+    if (file->bytes_written > 0
-            strncmp(file->absolute_path, "\\Download\\", 10) == 0) {
+            && strncmp(file->absolute_path, "\\Download\\", 10) == 0
+			&& !((guac_rdp_fs*) device->data)->disable_download) {
         guac_client_for_owner(svc->client, guac_rdp_download_to_user, file->absolute_path);
         guac_rdp_fs_delete((guac_rdp_fs*) device->data, iorequest->file_id);
     }

src/protocols/rdp/fs.c

@@ -43,7 +43,7 @@
 #include <unistd.h>
 
 guac_rdp_fs* guac_rdp_fs_alloc(guac_client* client, const char* drive_path,
-        int create_drive_path) {
+        int create_drive_path, int disable_download, int disable_upload) {
 
     /* Create drive path if it does not exist */
     if (create_drive_path) {
@@ -65,6 +65,8 @@ guac_rdp_fs* guac_rdp_fs_alloc(guac_client* client, const char* drive_path,
     fs->drive_path = strdup(drive_path);
     fs->file_id_pool = guac_pool_alloc(0);
     fs->open_files = 0;
+    fs->disable_download = disable_download;
+    fs->disable_upload = disable_upload;
 
     return fs;
 
@@ -81,7 +83,11 @@ guac_object* guac_rdp_fs_alloc_object(guac_rdp_fs* fs, guac_user* user) {
     /* Init filesystem */
     guac_object* fs_object = guac_user_alloc_object(user);
     fs_object->get_handler = guac_rdp_download_get_handler;
+    
+    /* Assign handler only if uploads are not disabled. */
+    if(!fs->disable_upload)
         fs_object->put_handler = guac_rdp_upload_put_handler;
+    
     fs_object->data = fs;
 
     /* Send filesystem to user */

src/protocols/rdp/fs.h

@@ -220,6 +220,16 @@ typedef struct guac_rdp_fs {
      */
     guac_rdp_fs_file files[GUAC_RDP_FS_MAX_FILES];
     
+    /**
+     * If downloads from the remote server to the browser should be disabled.
+     */
+    int disable_download;
+    
+    /**
+     * If uploads from the browser to the remote server should be disabled.
+     */
+    int disable_upload;
+
 } guac_rdp_fs;
 
 /**
@@ -259,11 +269,19 @@ typedef struct guac_rdp_fs_info {
  *     Non-zero if the drive path specified should be automatically created if
  *     it does not yet exist, zero otherwise.
  * 
+ * @param disable_download
+ *     Non-zero if downloads from the remote server to the local browser should
+ *     be disabled.
+ * 
+ * @param disable_upload
+ *     Non-zero if uploads from the browser to the remote server should be
+ *     disabled.
+ *
  * @return
  *     The newly-allocated filesystem.
  */
 guac_rdp_fs* guac_rdp_fs_alloc(guac_client* client, const char* drive_path,
-        int create_drive_path);
+        int create_drive_path, int disable_download, int disable_upload);
 
 /**
  * Frees the given filesystem.

src/protocols/rdp/rdp.c

@@ -548,7 +548,8 @@ void* guac_rdp_client_thread(void* data) {
         /* Allocate actual emulated filesystem */
         rdp_client->filesystem =
             guac_rdp_fs_alloc(client, settings->drive_path,
-                    settings->create_drive_path);
+                    settings->create_drive_path, settings->disable_download,
+                    settings->disable_upload);
 
         /* Expose filesystem to owner */
         guac_client_for_owner(client, guac_rdp_fs_expose,
@@ -617,7 +618,9 @@ void* guac_rdp_client_thread(void* data) {
         /* Load and expose filesystem */
         rdp_client->sftp_filesystem =
             guac_common_ssh_create_sftp_filesystem(rdp_client->sftp_session,
-                    settings->sftp_root_directory, NULL);
+                    settings->sftp_root_directory, NULL,
+                    settings->sftp_disable_download,
+                    settings->sftp_disable_upload);
 
         /* Expose filesystem to connection owner */
         guac_client_for_owner(client,

src/protocols/rdp/user.c

@@ -131,16 +131,17 @@ int guac_rdp_user_file_handler(guac_user* user, guac_stream* stream,
 #ifdef ENABLE_COMMON_SSH
     guac_rdp_settings* settings = rdp_client->settings;
 
-    /* If SFTP is enabled, it should be used for default uploads only if RDPDR
+    /* If SFTP is enabled and SFTP uploads have not been disabled, it should be
-     * is not enabled or its upload directory has been set */
+     * used for default uploads only if RDPDR is not enabled or its upload
-    if (rdp_client->sftp_filesystem != NULL) {
+     * directory has been set */
+    if (rdp_client->sftp_filesystem != NULL && !settings->sftp_disable_upload) {
         if (!settings->drive_enabled || settings->sftp_directory != NULL)
             return guac_rdp_sftp_file_handler(user, stream, mimetype, filename);
     }
 #endif
 
     /* Default to using RDPDR uploads (if enabled) */
-    if (rdp_client->filesystem != NULL)
+    if (rdp_client->filesystem != NULL && !settings->disable_upload)
         return guac_rdp_upload_file_handler(user, stream, mimetype, filename);
 
     /* File transfer not enabled */

src/protocols/ssh/settings.c

@@ -368,7 +368,7 @@ guac_ssh_settings* guac_ssh_parse_args(guac_user* user,
     /* Disable file downloads. */
     settings->sftp_disable_download =
         guac_user_parse_args_boolean(user, GUAC_SSH_CLIENT_ARGS, argv,
-                IDX_SFTP_DISABLE_DOWNLAOD, false);
+                IDX_SFTP_DISABLE_DOWNLOAD, false);
     
     /* Disable file uploads. */
     settings->sftp_disable_upload =

src/protocols/ssh/settings.h

@@ -185,14 +185,14 @@ typedef struct guac_ssh_settings {
      * downloads will not be allowed over SFTP.  If not set or set to false, file
      * downloads will be allowed.
      */
-    bool disable_download;
+    bool sftp_disable_download;
     
     /**
      * Whether file uploads over SFTP should be disabled.  If set to true, file
      * uploads will not be allowed over SFTP.  If not set or set to false, file
      * uploads will be allowed.
      */
-    bool disable_upload;
+    bool sftp_disable_upload;
 
 #ifdef ENABLE_SSH_AGENT
     /**

src/protocols/ssh/ssh.c

@@ -320,7 +320,8 @@ void* ssh_client_thread(void* data) {
         /* Request SFTP */
         ssh_client->sftp_filesystem = guac_common_ssh_create_sftp_filesystem(
                     ssh_client->sftp_session, settings->sftp_root_directory,
-                    NULL);
+                    NULL, settings->sftp_disable_download,
+                    settings->sftp_disable_upload);
 
         /* Expose filesystem to connection owner */
         guac_client_for_owner(client,
@@ -328,7 +329,10 @@ void* ssh_client_thread(void* data) {
                 ssh_client->sftp_filesystem);
 
         /* Init handlers for Guacamole-specific console codes */
+        if (!settings->sftp_disable_upload)
             ssh_client->term->upload_path_handler = guac_sftp_set_upload_path;
+        
+        if (!settings->sftp_disable_download)
             ssh_client->term->file_download_handler = guac_sftp_download_file;
 
         guac_client_log(client, GUAC_LOG_DEBUG, "SFTP session initialized");

src/protocols/ssh/user.c

@@ -99,7 +99,7 @@ int guac_ssh_user_join_handler(guac_user* user, int argc, char** argv) {
         user->size_handler = guac_ssh_user_size_handler;
 
         /* Set generic (non-filesystem) file upload handler */
-        if (settings->enable_sftp)
+        if (settings->enable_sftp && !settings->sftp_disable_upload)
             user->file_handler = guac_sftp_file_handler;
 
     }

src/protocols/vnc/user.c

@@ -101,7 +101,7 @@ int guac_vnc_user_join_handler(guac_user* user, int argc, char** argv) {
 
 #ifdef ENABLE_COMMON_SSH
         /* Set generic (non-filesystem) file upload handler */
-        if (settings->enable_sftp)
+        if (settings->enable_sftp && !settings->sftp_disable_upload)
             user->file_handler = guac_vnc_sftp_file_handler;
 #endif
 

src/protocols/vnc/vnc.c

@@ -342,7 +342,9 @@ void* guac_vnc_client_thread(void* data) {
         /* Load filesystem */
         vnc_client->sftp_filesystem =
             guac_common_ssh_create_sftp_filesystem(vnc_client->sftp_session,
-                    settings->sftp_root_directory, NULL);
+                    settings->sftp_root_directory, NULL,
+                    settings->sftp_disable_download,
+                    settings->sftp_disable_upload);
 
         /* Expose filesystem to connection owner */
         guac_client_for_owner(client,