Post Mortem: A single whitespace character
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Post Mortem: A single whitespace character
1–10 of 209 posts
Re: Post Mortem: A single whitespace character
#2I experienced a similar problem with a POP3 utility that I had written years ago. I had been appending an extra space to the end of each text line (before the CRLF ).
There were a few people using this utility with no problems until one day a particular POP3 server no longer tolerated my utility's malformed requests.
Re: Post Mortem: A single whitespace character
#3Cowboy is quite a well respected we server of the Erlang flavor. I'd guess heroku rejiggered something in their stack, perhaps adding cowboy as a reverse proxy or load balancer in front of their junk.
Cowboy apparently shot yor no-good dirty sidewinding web requests in the face.
Re: Post Mortem: A single whitespace character
#4[deleted]
Re: Post Mortem: A single whitespace character
#5It's technically correct, according to the HTTP spec there must be a single "SP" character between the elements in the Request-Line:
Request-Line = Method SP Request-URI SP HTTP-Version CRLF
Source: http://www.w3.org/Protocols/rfc2616/rfc2616-sec5.html#sec5.1
Re: Post Mortem: A single whitespace character
#6The Server: cowboy tag is from an Erlang web server:
https://github.com/ninenines/cowboy/blob/master/src/cowboy_p...
I'm guessing around here would be interesting to add a test case to handle.
As far as whose server this is? I'd guess Heroku or AWS, though it's plenty possible T-Mobile could have devised some proxy to inspect traffic, but seems unlikely they would do so with Cowboy?
Re: Post Mortem: A single whitespace character
#7This very example -- requests were technically illegal all the time without devs realizing, but something in the stack changed to start rejecting them -- demonstrates the fallacy of the "be liberal in what you accept, strict in what you issue" principal. If all the web servers involved had been strict in rejecting the illegal request from the start, they would have noticed the bug in development before deploying to firmware in the field.
Re: Post Mortem: A single whitespace character
#8What's the deal with all the scrollbars on this page?
Re: Post Mortem: A single whitespace character
#9The Server: cowboy tag is from an Erlang web server: https://github.com/ninenines/cowboy/blob/master/src/cowboy_p... I'm guessing around here would be interesting to add a test case to handle. As far as whose server this is? I'd guess Heroku or AWS, though it's plenty possible T-Mobile could have devised some proxy to inspect traffic, but seems unlikely they would do so with Cowboy?
T-mobile is known to have, in the past at least, used Erlang. And Cowboy is one of the most popular web servers within that community at this point.
Re: Post Mortem: A single whitespace character
#10It scares me to think all of these requests run over unencrypted HTTP.