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Wireshark-dev: [Wireshark-dev] Restrictions on dots ('.') in filter names

From: Peter Wu <peter@xxxxxxxxxxxxx>
Date: Mon, 16 Apr 2018 16:12:09 +0200
Hi,

Filter names were so far limited to alphanumeric, underscore ('_'),
hyphen ('-') and period ('.') characters. I intend to introduce
additional restrictions:

- Forbid ".foo" (leading dots)
- Forbid "foo..bar" (double "..")
- Forbid "foo." (trailing dots)

The second restriction is needed to support "f in {x..y}" in a cleaner
way for https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=14180

The other changes seem to make sense to me. There was no dissector that
uses ".foo" and all users of "foo." clearly did not intend to use it as
such (typos, truncated field names).

Note that there are fields with leading "_" ("_ws.malformed"), but those
are special cases. As such I only limited this restriction to just ".".

If there is any compelling reason to support these, please speak up now.

Proposed patch is at https://code.wireshark.org/review/26967
and I plan to backport it to 2.6 (unreleased) for future proofing
(unless there are objections).
-- 
Kind regards,
Peter Wu
https://lekensteyn.nl