Fixes

nomadnet/Conversation.py

@@ -1,4 +1,5 @@
 import os
+import re
 import RNS
 import LXMF
 import shutil
@@ -459,22 +460,25 @@ class ConversationMessage:
                     if found_in_fields:
                         names = []
                         file_atts = fields.get(LXMF.FIELD_FILE_ATTACHMENTS, [])
-                        for att in file_atts:
+                        for idx, att in enumerate(file_atts):
                             if isinstance(att, list) and len(att) >= 2:
                                 size = len(att[1]) if isinstance(att[1], bytes) else 0
-                                names.append(("file", str(att[0]), size))
+                                safe = ConversationMessage.safe_attachment_name(att[0], fallback="attachment_"+str(idx))
+                                names.append(("file", safe, size))
                         if LXMF.FIELD_IMAGE in fields:
                             fmt, data = ConversationMessage._unpack_media_field(fields[LXMF.FIELD_IMAGE])
                             if data:
                                 size = len(data)
                                 ext = ConversationMessage._ext_from_media_format(fmt, data)
-                                names.append(("file", "image"+ext, size))
+                                safe = ConversationMessage.safe_attachment_name("image"+ext, fallback="image")
+                                names.append(("file", safe, size))
                         if LXMF.FIELD_AUDIO in fields:
                             fmt, data = ConversationMessage._unpack_media_field(fields[LXMF.FIELD_AUDIO])
                             if data:
                                 size = len(data)
                                 ext = ConversationMessage._ext_from_media_format(fmt, data, is_audio=True)
-                                names.append(("file", "audio"+ext, size))
+                                safe = ConversationMessage.safe_attachment_name("audio"+ext, fallback="audio")
+                                names.append(("file", safe, size))
                         self._cached_has_attachments = True
                         self._cached_attachment_names = names
 
@@ -674,11 +678,18 @@ class ConversationMessage:
             try:
                 with open(manifest_path, "rb") as f:
                     manifest = msgpack.unpackb(f.read(), raw=False)
-                    for f in manifest["files"]:
-                        f["name"] = os.path.basename(f["name"]).encode("utf-8").decode("utf-8")
-
+                    safe_files = []
+                    for idx, entry in enumerate(manifest.get("files", [])):
+                        if not isinstance(entry, dict):
+                            continue
+                        entry["name"] = ConversationMessage.safe_attachment_name(entry.get("name"), fallback="attachment_"+str(idx))
+                        stored = entry.get("stored_name")
+                        if not isinstance(stored, str) or not re.fullmatch(r"file_\d+", stored):
+                            continue
+                        safe_files.append(entry)
+                    manifest["files"] = safe_files
                     return manifest
-            
+
             except Exception as e:
                 RNS.log(f"Error loading attachment manifest: {e}")
                 return None
@@ -714,12 +725,12 @@ class ConversationMessage:
             for idx, att in enumerate(file_attachments):
                 try:
                     if isinstance(att, list) and len(att) >= 2:
-                        filename = os.path.basename(str(att[0])).encode("utf-8").decode("utf-8")
+                        filename = ConversationMessage.safe_attachment_name(att[0], fallback="attachment_"+str(idx))
                         data = att[1] if isinstance(att[1], bytes) else b""
                         stored_name = "file_"+str(idx)
                         with open(os.path.join(att_dir, stored_name), "wb") as f: f.write(data)
                         manifest["files"].append({"name": filename, "stored_name": stored_name, "size": len(data)})
-                
+
                 except Exception as e:
                     RNS.log(f"Error decoding file attachment: {e}", RNS.LOG_ERROR)
                     continue
@@ -728,7 +739,7 @@ class ConversationMessage:
             fmt, data = ConversationMessage._unpack_media_field(fields[LXMF.FIELD_IMAGE])
             if data:
                 ext = ConversationMessage._ext_from_media_format(fmt, data)
-                filename = "image" + ext
+                filename = ConversationMessage.safe_attachment_name("image" + ext, fallback="image")
                 stored_name = "file_"+str(len(manifest["files"]))
                 with open(os.path.join(att_dir, stored_name), "wb") as f:
                     f.write(data)
@@ -738,7 +749,7 @@ class ConversationMessage:
             fmt, data = ConversationMessage._unpack_media_field(fields[LXMF.FIELD_AUDIO])
             if data:
                 ext = ConversationMessage._ext_from_media_format(fmt, data, is_audio=True)
-                filename = "audio" + ext
+                filename = ConversationMessage.safe_attachment_name("audio" + ext, fallback="audio")
                 stored_name = "file_"+str(len(manifest["files"]))
                 with open(os.path.join(att_dir, stored_name), "wb") as f:
                     f.write(data)
@@ -747,6 +758,29 @@ class ConversationMessage:
         with open(os.path.join(att_dir, "manifest"), "wb") as f:
             f.write(msgpack.packb(manifest))
 
+    @staticmethod
+    def safe_attachment_name(name, fallback="attachment"):
+        try:
+            if isinstance(name, bytes):
+                name = name.decode("utf-8", errors="replace")
+            elif not isinstance(name, str):
+                name = str(name) if name is not None else ""
+        except Exception:
+            name = ""
+        name = re.sub(r"[\x00-\x1f\x7f]", "", name)
+        parts = re.split(r"[/\\]", name)
+        name = parts[-1] if parts else ""
+        if ":" in name:
+            name = name.split(":")[-1]
+        name = name.lstrip(".")
+        if not name or name in (".", ".."):
+            return fallback
+        if len(name) > 200:
+            base, ext = os.path.splitext(name)
+            ext = ext[:16]
+            name = base[:200 - len(ext)] + ext
+        return name
+
     @staticmethod
     def _unpack_media_field(field_data):
         """Normalize FIELD_IMAGE/FIELD_AUDIO which can be raw bytes or [format, bytes].
@@ -789,10 +823,10 @@ class ConversationMessage:
 
     @staticmethod
     def _ext_from_media_format(fmt, data, is_audio=False):
-        """Derive file extension from format identifier and data.
-        fmt can be a string ('webp'), an integer (LXMF audio mode), or None."""
         if isinstance(fmt, str) and len(fmt) > 0:
-            return "." + fmt.lower().strip(".")
+            safe = re.sub(r"[^A-Za-z0-9]", "", fmt).lower()[:8]
+            if safe:
+                return "." + safe
         if isinstance(fmt, int) and is_audio:
             if fmt >= 16 and fmt <= 25:
                 return ".ogg"

nomadnet/ui/textui/Channels.py

@@ -372,6 +372,7 @@ class RoomWidget(urwid.WidgetWrap):
         editor = RoomMessageEdit(caption="", edit_text="", multiline=True)
         editor.delegate = self
         self.editor = editor
+        urwid.connect_signal(editor, "postchange", self._on_editor_change)
         editor_attr = urwid.AttrMap(editor, "msg_editor")
 
         self.link_delegate = _ChatLinkDelegate(self.display, self.hub)
@@ -474,6 +475,10 @@ class RoomWidget(urwid.WidgetWrap):
 
         self.messagelist = IndicativeListBox(widgets, position=len(widgets)-1)
         self.messagelist.name = "messagelist"
+        try:
+            self.messagelist._listbox.set_focus_valign("bottom")
+        except Exception:
+            pass
         if replace and hasattr(self, "frame"):
             self.frame.contents["body"] = (self.messagelist, None)
         if hasattr(self, "users_pile"):
@@ -495,6 +500,7 @@ class RoomWidget(urwid.WidgetWrap):
                 del body[0]
             try:
                 self.messagelist._listbox.set_focus(len(body)-1)
+                self.messagelist._listbox.set_focus_valign("bottom")
             except Exception:
                 pass
         except Exception as e:
@@ -503,6 +509,17 @@ class RoomWidget(urwid.WidgetWrap):
         if hasattr(self, "users_pile"):
             self._refresh_users_pane()
 
+    def _on_editor_change(self, editor, old_text):
+        if self.messagelist is None:
+            return
+        try:
+            body = self.messagelist._listbox.body
+            if len(body) > 0:
+                self.messagelist._listbox.set_focus(len(body)-1)
+                self.messagelist._listbox.set_focus_valign("bottom")
+        except Exception:
+            pass
+
     def send_message(self):
         text = self.editor.get_edit_text()
         if not text.strip():

nomadnet/ui/textui/Conversations.py

@@ -1798,32 +1798,34 @@ class ClickableAttachment(urwid.Text):
             self.set_text("  "+g["cross"]+" Save failed: "+str(e))
 
 
-def _copy_attachment_to_dest(filename, src_path):
+def _resolve_attachment_save_path(filename):
     app = nomadnet.NomadNetworkApp.get_shared_instance()
     save_dir = app.attachment_save_path if app.attachment_save_path else app.downloads_path
     if not os.path.isdir(save_dir):
         os.makedirs(save_dir)
-    save_path = os.path.join(save_dir, filename)
+    safe_name = ConversationMessage.safe_attachment_name(filename)
+    base_dir = os.path.realpath(save_dir) + os.sep
+    candidate = os.path.realpath(os.path.join(save_dir, safe_name))
+    if not (candidate + os.sep).startswith(base_dir):
+        raise OSError(13, os.strerror(13))
     counter = 0
-    base, ext = os.path.splitext(filename)
-    while os.path.isfile(save_path):
+    base, ext = os.path.splitext(safe_name)
+    while os.path.isfile(candidate):
         counter += 1
-        save_path = os.path.join(save_dir, base+"_"+str(counter)+ext)
+        candidate = os.path.realpath(os.path.join(save_dir, base+"_"+str(counter)+ext))
+        if not (candidate + os.sep).startswith(base_dir):
+            raise OSError(13, os.strerror(13))
+    return candidate
+
+
+def _copy_attachment_to_dest(filename, src_path):
+    save_path = _resolve_attachment_save_path(filename)
     shutil.copy2(src_path, save_path)
     return save_path
 
 
 def _save_attachment_to_disk(filename, data):
-    app = nomadnet.NomadNetworkApp.get_shared_instance()
-    save_dir = app.attachment_save_path if app.attachment_save_path else app.downloads_path
-    if not os.path.isdir(save_dir):
-        os.makedirs(save_dir)
-    save_path = os.path.join(save_dir, filename)
-    counter = 0
-    base, ext = os.path.splitext(filename)
-    while os.path.isfile(save_path):
-        counter += 1
-        save_path = os.path.join(save_dir, base+"_"+str(counter)+ext)
+    save_path = _resolve_attachment_save_path(filename)
     with open(save_path, "wb") as f:
         f.write(data)
     return save_path