1.727

W/tools/fixup_email.py

@@ -0,0 +1,107 @@
+#!/usr/bin/python
+
+NUKE_HDRS = [
+    # (hdr, max_lines, max_items, max_bytes). (-1 => unlimited).
+    ("References", 485, 485, 40000),
+]
+MAX_LINE_LENGTH = 996
+NUKE_8BIT = True
+FORCE_REWRITE = False
+
+import sys
+from email.parser import Parser
+from email.generator import Generator
+from email import utils
+from cStringIO import StringIO
+
+# NB: utils._qencode() replaces ALL ' ' with '=20', as required by QP
+# header strings. We only need to encode trailing whitespace in message
+# body. quopri.encodestring (used by utils._qencode()) does this already.
+from quopri import encodestring as qp_encode
+
+fp            = open(sys.argv[1], "rb") if len(sys.argv) > 1 else sys.stdin
+msg_text_crnl = fp.read(); fp.close()
+msg_text_nl   = msg_text_crnl.replace("\r\n", "\n")
+
+# We want to preserve CRLF and any leading "From" from source message
+CRLF          = "\r\n" if (len(msg_text_nl) < len(msg_text_crnl)) else "\n"
+UNIXFROM      = msg_text_nl.startswith("From ")
+
+def rewrite(part):
+    need_rewrite = False
+
+    for hdr in part.values():
+        if max([len(i) for i in hdr.split('\n')]) > MAX_LINE_LENGTH:
+            need_rewrite = True # Force MIME rewrite if we have long headers
+            sys.stderr.write("FIXUP NEXT: Rewrite forced by long header line\n")
+
+    for hdr, max_lines, max_items, max_bytes in NUKE_HDRS:
+        (hdr, val) = (hdr.lower(), msg.get(hdr))
+        if (val and ((max_lines >= 0 and len(val.split('\n')) > max_lines) or
+                     (max_items >= 0 and len(val.split()) > max_items) or
+                     (max_bytes >= 0 and len(val) > max_bytes))):
+            del msg[hdr]
+            sys.stderr.write("FIXUP NEXT: Removed long header line: "+hdr+"\n")
+            need_rewrite = True
+
+    if part.is_multipart():
+        for subpart in part.get_payload():
+            if rewrite(subpart):
+                need_rewrite = True
+        return need_rewrite
+
+    payload = part.get_payload()
+    max_line_length = max([ len(i) for i in payload.split('\n') ])
+
+    cte     = part.get('content-transfer-encoding', '').lower().strip()
+    if cte in ['8bit', '7bit', 'binary', '']:
+        # Encode unencoded forms which contain 8bit characters or long lines
+        update_cte = part.replace_header if (cte != '') else part.add_header
+        nonascii_count = [(ord(c) >= 128) for c in payload].count(True)
+        if ((NUKE_8BIT and nonascii_count > 0) or
+            max_line_length > MAX_LINE_LENGTH):
+            if nonascii_count < 100: 
+                part.set_payload(qp_encode(payload))
+                update_cte('Content-Transfer-Encoding', "quoted-printable")
+            else:
+                part.set_payload(utils._bencode(payload))
+                update_cte('Content-Transfer-Encoding', "base64")
+            need_rewrite = True
+    elif cte in ['quoted-printable', 'base64']:
+        # Recode quoted-printable or base64 with long lines
+        if max_line_length > MAX_LINE_LENGTH:
+            if cte == 'quoted-printable':
+                raw=utils._qdecode(payload)
+                part.set_payload(qp_encode(raw))
+                need_rewrite = True
+            elif cte == 'base64':
+                try:
+                    raw=utils._bdecode(payload)
+                    part.set_payload(utils._bencode(raw))
+                    need_rewrite = True
+                except binascii.Error:
+                    pass
+
+    newcte =  part.get('content-transfer-encoding', '').lower().strip()
+    if (newcte != cte):
+        part.add_header('X-Mime-Autoconverted',
+                        "from " + (cte or "none") + " to " + newcte)
+        sys.stderr.write("FIXUP NEXT: Attachment converted " +
+                         "from " + (cte or "none") + " to " + newcte + "\n")
+    return need_rewrite
+
+msg=Parser().parsestr(msg_text_nl)
+
+if not rewrite(msg) and not FORCE_REWRITE:
+    sys.stdout.write(msg_text_crnl)
+    sys.exit(0)
+
+buffer = StringIO()
+gen=Generator(buffer, mangle_from_=False, maxheaderlen=MAX_LINE_LENGTH)
+gen.flatten(msg, unixfrom=UNIXFROM)
+
+buffer.seek(0)
+for line in buffer.readlines():
+    sys.stdout.write(line.rstrip('\n')); sys.stdout.write(CRLF)
+buffer.close()
+sys.exit(0)