routine backup

1 files changed, 113 insertions, 0 deletions

diff --git a/profanity-aesgcm-handler b/profanity-aesgcm-handler
new file mode 100755
index 0000000..0ea5e19
--- /dev/null
+++ b/profanity-aesgcm-handler
@@ -0,0 +1,113 @@
+#!/usr/bin/env python3
+
+import os
+import re
+import sys
+import urllib.parse
+from pathlib import Path
+
+import requests
+from cryptography.hazmat.primitives.ciphers.aead import AESGCM
+
+
+home = Path.home()
+if (home / "downloads").exists():
+    DOWNLOAD_DIR = home / "downloads" / "xmpp"
+    DOWNLOAD_DIR.mkdir(parents=True, exist_ok=True)
+else:
+    DOWNLOAD_DIR = home / "Downloads" / "xmpp"
+    DOWNLOAD_DIR.mkdir(parents=True, exist_ok=True)
+
+def log(msg: str) -> None:
+    log_file = Path.home() / ".local" / "share" / "profanity-aesgcm" / "handler.log"
+    log_file.parent.mkdir(parents=True, exist_ok=True)
+    with log_file.open("a", encoding="utf-8") as f:
+        f.write(msg + "\n")
+
+
+def extract_uri(message: str) -> str | None:
+    m = re.search(r'(aesgcm://\S+)', message)
+    return m.group(1) if m else None
+
+
+def parse_aesgcm_uri(uri: str):
+    parsed = urllib.parse.urlparse(uri)
+
+    if parsed.scheme != "aesgcm":
+        raise ValueError("Unsupported scheme")
+
+    fragment = parsed.fragment.strip()
+    frag_hex = "".join(fragment.split())  # remove accidental spaces/newlines
+
+    # XEP-0454 style: 12-byte IV (24 hex chars) + 32-byte key (64 hex chars)
+    if len(frag_hex) < 88:
+        raise ValueError(f"Fragment too short: {len(frag_hex)} hex chars")
+
+    iv_hex = frag_hex[:24]
+    key_hex = frag_hex[24:88]
+
+    iv = bytes.fromhex(iv_hex)
+    key = bytes.fromhex(key_hex)
+
+    https_url = urllib.parse.urlunparse(("https", parsed.netloc, parsed.path, "", "", ""))
+    filename = os.path.basename(parsed.path) or "download.bin"
+
+    return https_url, filename, key, iv
+
+
+def download_file(url: str) -> bytes:
+    r = requests.get(url, timeout=60)
+    r.raise_for_status()
+    return r.content
+
+
+def decrypt_xmpp_aesgcm(data: bytes, key: bytes, iv: bytes) -> bytes:
+    # AESGCM.decrypt expects ciphertext || tag
+    aesgcm = AESGCM(key)
+    return aesgcm.decrypt(iv, data, None)
+
+
+def unique_path(path: Path) -> Path:
+    if not path.exists():
+        return path
+
+    stem = path.stem
+    suffix = path.suffix
+
+    for i in range(1, 1000):
+        candidate = path.with_name(f"{stem}-{i}{suffix}")
+        if not candidate.exists():
+            return candidate
+
+    raise RuntimeError("Could not create unique filename")
+
+def main():
+    if len(sys.argv) < 2:
+        sys.exit(0)
+
+    message = sys.argv[1]
+    uri = extract_uri(message)
+    if not uri:
+        sys.exit(0)
+
+    try:
+        https_url, filename, key, iv = parse_aesgcm_uri(uri)
+        enc = download_file(https_url)
+        plain = decrypt_xmpp_aesgcm(enc, key, iv)
+
+        out_path = unique_path(DOWNLOAD_DIR / filename)
+        out_path.write_bytes(plain)
+
+        log(f"OK saved: {out_path}")
+        print(str(out_path))
+
+        # Optional: uncomment if you want auto-open on desktop
+        # os.system(f'xdg-open "{out_path}" >/dev/null 2>&1 &')
+
+    except Exception as e:
+        log(f"ERROR: {e}")
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()