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Timeout for TLS (using WinSSL)

From: Marcus Ilgner <>
Date: Fri, 4 Apr 2014 10:56:35 +0200

Hello list,

using libcurl 7.36 on Windows, compiled with WinSSL, I get a timeout
when connecting to a HTTPS URL. Looking at the Wireshark dump, I can

TLSv1 Client Key Exchange, Change Cipher Spec, Encrypted Handshake Message
TLSv1 New Session Ticket, Change Cipher Spec, Encrypted Handshake Message

followed by the TCP ACK from my client. But in my application, no
callbacks are invoked and the connection finally times out.
I have tried disabling VERIFYPEER and VERIFYHOST even though the
certificate is correct but it didn't make any difference.
Now I'm wondering whether there's anything I may have forgotten or
what I can do to debug this on my application level. Since there's no
SSL_CTX_FUNCTION with WinSSL, I'm not sure what I can do at this
For completeness: my browser always negotiates TLS 1.0 with this
server and does not go higher. Chrome does 256bit AES CBC while
Firefox goes to AES 128 CBC but both of these are basic enough that it
should work.
As things work fine when using unsecured connections against a local
fake server, I'll check whether I can get it to work with another
libcurl built against OpenSSL. But I'd prefer if I didn't have this
additional dependency when running on Windows, so any insight you
could provide is greatly appreciated.

All the best
List admin:
Received on 2014-04-04