Update docx, pptx, and xlsx skills (#1447)

Add support for template formats (.dotx, .potx, .xltx) across validation and the helper scripts. Consolidate the shared office helpers into a single module, replacing the pack/unpack pipeline with explicit zip/unzip steps. Extraction now rejects symlink and path-traversal archive entries. Move run merging to a standalone docx script, since it only ever applied to Word documents. Fix the redlining validator so it compares against the original even when a document has no tracked changes, which is when an untracked edit would otherwise go unreported. Provision a LibreOffice user profile per invocation so conversions work in sandboxed environments. Trim the skill docs to the guidance that earns its place.
2026-08-02 13:05:28 +08:00 · 2026-07-16 19:47:37 -07:00
parent 9d2f1ae187
commit fa0fa64bdc
53 changed files with 4147 additions and 4442 deletions
@@ -0,0 +1,111 @@
+import os
+import posixpath
+import re
+import stat
+import tempfile
+import urllib.parse
+import zipfile
+from pathlib import Path
+
+OOXML_FAMILY = {
+    ".docx": "docx",
+    ".dotx": "docx",
+    ".pptx": "pptx",
+    ".potx": "pptx",
+    ".xlsx": "xlsx",
+    ".xltx": "xlsx",
+}
+
+_SCHEME_RE = re.compile(r"^[A-Za-z][A-Za-z0-9+.\-]*:")
+
+SLIDE_REL_TYPE = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/slide"
+
+
+def opc_target(target: str, source_part: str, target_mode: str = "") -> str | None:
+    if not target:
+        return None
+    if target_mode.lower() == "external":
+        return None
+    if _SCHEME_RE.match(target):
+        return None
+
+    target = urllib.parse.unquote(target)
+
+    if "\\" in target:
+        raise ValueError(f"relationship target is not a POSIX part name: {target!r}")
+
+    if target.startswith("/"):
+        joined = target.lstrip("/")
+    else:
+        joined = posixpath.join(posixpath.dirname(source_part), target)
+
+    parts: list[str] = []
+    for segment in posixpath.normpath(joined).split("/"):
+        if segment in ("", "."):
+            continue
+        if segment == "..":
+            if not parts:
+                raise ValueError(f"relationship target escapes the package: {target!r}")
+            parts.pop()
+        else:
+            parts.append(segment)
+
+    if not parts:
+        raise ValueError(f"relationship target resolves to nothing: {target!r}")
+    return "/".join(parts)
+
+
+def rels_source_part(rels_file: Path, unpacked_dir: Path) -> str:
+    owner_dir = rels_file.parent.parent.relative_to(unpacked_dir)
+    return posixpath.join(owner_dir.as_posix(), rels_file.name[: -len(".rels")]).lstrip("./")
+
+
+def part_text(data: bytes) -> str:
+    return data.decode("utf-8", "surrogateescape")
+
+
+XML_SPACE = " \t\r\n"
+
+
+def rendered_text(text: str, preserve: bool) -> str:
+    return text if preserve else text.strip(XML_SPACE)
+
+
+def safe_extract(zf: zipfile.ZipFile, dest: Path) -> None:
+    dest = dest.resolve()
+    for m in zf.infolist():
+        if stat.S_ISLNK(m.external_attr >> 16):
+            raise ValueError(f"symlink archive entry not allowed: {m.filename!r}")
+        target = (dest / m.filename).resolve()
+        if not target.is_relative_to(dest):
+            raise ValueError(f"unsafe archive entry: {m.filename!r}")
+        zf.extract(m, dest)
+
+
+def rezip(src_dir: Path, out_path: Path) -> None:
+    files = sorted(p for p in src_dir.rglob("*") if p.is_file())
+    ct = src_dir / "[Content_Types].xml"
+    fd, tmp_name = tempfile.mkstemp(
+        prefix=out_path.name + ".", suffix=".tmp", dir=out_path.parent
+    )
+    tmp_out = Path(tmp_name)
+    try:
+        with os.fdopen(fd, "wb") as fh:
+            with zipfile.ZipFile(fh, "w", zipfile.ZIP_DEFLATED) as zf:
+                if ct.exists():
+                    zf.write(ct, ct.relative_to(src_dir), compress_type=zipfile.ZIP_STORED)
+                for f in files:
+                    if f == ct:
+                        continue
+                    zf.write(f, f.relative_to(src_dir))
+        if out_path.exists():
+            mode = out_path.stat().st_mode & 0o777
+        else:
+            umask = os.umask(0)
+            os.umask(umask)
+            mode = 0o666 & ~umask
+        os.chmod(tmp_out, mode)
+        os.replace(tmp_out, out_path)
+    finally:
+        if tmp_out.exists():
+            tmp_out.unlink()