New submission from Bryce Drennan <pyt...@accounts.brycedrennan.com>:
Since Python 3.6.4 folding of unstructured headers uses the encoded words syntax even if there are no special characters. This makes DKIM-Signature headers that are unreadable to google's gmail servers. It may be that encoded-words are not valid in this header. I don't see them mentioned here: https://tools.ietf.org/html/rfc6376#page-8 Here is the smallest test case I could create to demonstrate the issue. One solution would be to add DKIM-Signature to the HeaderRegistry but I'm not yet expert enough to execute this. I went down that path for a few hours. Didn't see a straight-forward way to disable encoded words. Setting EmailPolicy(max_line_length=None) does output without encoded words but I worry that will cause different incompatibility issues. from email.headerregistry import HeaderRegistry from email.policy import SMTP def test_unstructured_encoded_word_folding(): header = HeaderRegistry()('DKIM-Signature', 'a' * 85) folded = header.fold(policy=SMTP.clone(refold_source=None)) print(f'\nDKIM-Signature: {header}') print(folded) assert '=?utf-8?q?' not in folded Output: DKIM-Signature: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa DKIM-Signature: =?utf-8?q?aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa?= =?utf-8?q?aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa?= AssertionError()! ---------- components: email messages: 326943 nosy: barry, bryced, r.david.murray priority: normal severity: normal status: open title: unnecessary encoded-words usage breaks DKIM signatures versions: Python 3.6, Python 3.7 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue34881> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
