Re: Bug: git behind proxy is broken in 2.34.1

[Jeff King <peff@peff.net>]

On Thu, Feb 16, 2023 at 06:55:42PM +0100, tm-uzr3z@entrap.de wrote:

> I just realized that git cloning behind a webproxy is broken in version
> 2.34.1 (Ubuntu 22.04).
> 
> The environment bash variables http_proxy, https_proxy, HTTP_PROXY and
> HTTPS_PROXY are all set with the value
> "http://myusername:mypassword@ourwebproxy:3128/".
> 
> git gives me the following error message on cloning:
> $git clone https://github.com/XXXX/YYYY
> fatal: unable to access 'https://github.com/XXXX/YYYY/': Received HTTP
> code 407 from proxy after CONNECT

Hmm. We do not have any test coverage for proxies at all. I took a stab
at adding some, and it was not too bad. But...it works!

However, I think there may be a number of possible configurations here.
In my tests, it is an http proxy over http, so it is issuing a GET with
a full URL in it, rather than using CONNECT.

So it may be that CONNECT is broken, but http-over-http proxying is not.
I couldn't get a working CONNECT set up at all (before even worrying
about the authentication step).

> On another very old machine with git 1.9.1 it requests the URL through the
> proxy, receives an http 407 authentication required, and repeats the
> request with credentials, which is allowed then.

That could be good news, as that would mean we might be able to bisect
between 1.9.1 and 2.34.1. However, since you said it was an older
machine, presumably other packages are old, too. I would not be
surprised if the difference is actually in libcurl, not Git.

Still, if you're able to build Git from source and bisect, that would be
worth trying.

-Peff