On Mon, 30 May 2005, Todd Kulesza wrote:

> I'm the author of a journal client (Drivel) that uses libcurl for network
> transactions.

Then you may enjoy the curl-library list more in the future...

> I recently received a bug report from a user with an IPv6 proxy server.
> When he tries to connect to IPv4 sites (namely www.livejournal.com) through
> the proxy server, Drivel is unable to complete the connection. A strace run
> reveals that connect is called with an invalid address:
>
> connect(16, {sa_family=AF_INET, sin_port=htons(470),
> sin_addr=inet_addr("0.0.7.209")}, 16) = -1 EINVAL (Invalid argument)

But what does a command line trace reveal?

  curl --trace-ascii [dump] URL

> I tried the Curl command-line client, and received an "invalid argument"
> error when specifying an IPv6 proxy server there as well.

Like how?

I tried this just now:

$ curl -x "ip6-localhost" localhost -v
* About to connect() to ip6-localhost port 1080
* Trying ::1... * Connection refused
* couldn't connect to host
* Closing connection #0
curl: (7) couldn't connect to host

Looks right to me. (And no, I don't have any IPv6 network setup either, only
local IPv6 enabled.)

Or are you setting a proxy using ipv6-style numeric address?

> We've been able to replicate this issue using Curl 7.12.3 and 7.14.0. Have
> we uncovered a bug, or are IPv6 proxy servers unsupported by Curl?

If they are unsupported, that is a bug!

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