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Re: Curl won't download file from server that only supports TLS v1.0?

From: Petr Pisar via curl-users <>
Date: Wed, 10 Jun 2020 20:10:08 +0200

On Wed, Jun 10, 2020 at 01:37:35PM -0400, John Klimek via curl-users wrote:
> Here is the result of [openssl s_client -connect]
> CONNECTED(00000003)
> 140544376776000:error:1425F102:SSL
> routines:ssl_choose_client_version:unsupported
> protocol:../ssl/statem/statem_lib.c:1941:
> ---
> no peer certificate available
> ---
> No client certificate CA names sent
> ---
> SSL handshake has read 62 bytes and written 316 bytes
> Verification: OK
> ---
> New, (NONE), Cipher is (NONE)
> Secure Renegotiation IS NOT supported
> Compression: NONE
> Expansion: NONE
> No ALPN negotiated
> Early data was not sent
> Verify return code: 0 (ok)
> ---
And the client exists with a non-zero exit code. This is how it behaves when
the protocol is disabled.

> Also, here is [openssl list -disabled]:
> Disabled algorithms:
> MD2
> MDC2
> RC5
> SSL3
If I compile OpenSSL 1.1.1g without TLSv1 support, the output is:

Disabled algorithms:

Just for a comparison, a working connection looks like:

No client certificate CA names sent
Peer signing digest: MD5-SHA1
Peer signature type: RSA
Server Temp Key: DH, 1024 bits

SSL handshake has read 5525 bytes and written 517 bytes
Verification: OK
New, SSLv3, Cipher is DHE-RSA-AES256-SHA
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
    Protocol  : TLSv1
    Cipher    : DHE-RSA-AES256-SHA
I think you have the protocol disabled by a run-time configuration. Where did
you get the OpenSSL? Try consult your vendor's documentation.
-- Petr


Received on 2020-06-10