epriestley adc2002d28 Make it easier to parse "X-Forwarded-For" with one or more load balancers ... Summary: Fixes T13392. If you have 17 load balancers in sequence, Phabricator will receive requests with at least 17 "X-Forwarded-For" components in the header. We want to select the 17th-from-last element, since prior elements are not trustworthy. This currently isn't very easy/obvious, and you have to add a kind of sketchy piece of custom code to `preamble.php` to do any "X-Forwarded-For" parsing. Make handling this correctly easier. Test Plan: - Ran unit tests. - Configured my local `preamble.php` to call `preamble_trust_x_forwarded_for_header(4)`, then made `/debug/` dump the header and the final value of `REMOTE_ADDR`. ``` $ curl http://local.phacility.com/debug/ <pre> HTTP_X_FORWARDED_FOR = FINAL REMOTE_ADDR = 127.0.0.1 </pre> ``` ``` $ curl -H 'X-Forwarded-For: 1.1.1.1, 2.2.2.2, 3.3.3.3, 4.4.4.4, 5.5.5.5, 6.6.6.6' http://local.phacility.com/debug/ <pre> HTTP_X_FORWARDED_FOR = 1.1.1.1, 2.2.2.2, 3.3.3.3, 4.4.4.4, 5.5.5.5, 6.6.6.6 FINAL REMOTE_ADDR = 3.3.3.3 </pre> ``` ``` $ curl -H 'X-Forwarded-For: 5.5.5.5, 6.6.6.6' http://local.phacility.com/debug/ <pre> HTTP_X_FORWARDED_FOR = 5.5.5.5, 6.6.6.6 FINAL REMOTE_ADDR = 5.5.5.5 </pre> ``` Maniphest Tasks: T13392 Differential Revision: https://secure.phabricator.com/D20785		2019-09-05 04:30:13 -07:00
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PhabricatorClientConnectionLimit.php	Modularize rate/connection limits in Phabricator	2017-10-13 13:12:05 -07:00
PhabricatorClientLimit.php	Modularize rate/connection limits in Phabricator	2017-10-13 13:12:05 -07:00
PhabricatorClientRateLimit.php	Tweak rate limiting point counts for omnipotent users	2017-10-16 06:43:54 -07:00
PhabricatorStartup.php	Improve top-level fatal exception handling in PHP 7+	2019-02-11 15:05:15 -08:00
preamble-utils.php	Make it easier to parse "X-Forwarded-For" with one or more load balancers	2019-09-05 04:30:13 -07:00