2 ms·
That's what Postel thought. He was wrong. Allowing everything creates a brittle system because the system has to accept all the undocumented behaviour that othe
by immibis 1y ago
That's what Postel thought. He was wrong. Allowing everything creates a brittle system because the system has to accept all the undocumented behaviour that other broken systems emit. If broken files were rejected quickly, nobody would generate them.
There's a difference between unknown extensions following a known format, and data that's simply broken (e.g. offset pointer past end of data).
- emmelaich 1y agoYou're not accounting for the incorrectly rejected file / protocols. And incomplete protocol specifications. And generally I think critics of Postel are lacking the context in which they were made. You and probably others would actually make similar decisions than Postel for many particular issues.
- SAI_Peregrinus 1y agoI disagree that I'd make similar decisions. Postel's Law is a big part of the reason Bleichenbacher attacks (adaptive chosen-ciphertext attacks)[1] stayed so common for so long. As an engineer responsible for the security I absolutely reject malformed inputs. https://en.wikipedia.org/wiki/Adaptive_chosen-ciphertext_attack https://en.wikipedia.org/wiki/Adaptive_chosen-ciphertext_att...
- emmelaich 1y agoBut that's what I'm saying; Postel may well have ALSO rejected malformed inputs in this particular case.