I know what I wrote,
what's your answer?

Thanks,
Walter

On 15/12/17 11:01:14, David Sommerseth <[email protected]> wrote:
On 15/12/17 11:07, Walter H. via Openvpn-users wrote:
 Hi folks,

 WinXP uses the latest package from here:
 https://openvpn.net/index.php/download/community-downloads.html
 ( OpenVPN 2.3.18 )

 and the Linux box is a CentOS 6 that uses the RPM package from EPEL
 ( OpenVPN 2.4.4 x86_64-redhat-linux-gnu [Fedora EPEL patched] [SSL
 (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKCS11] [MH/PKTINFO] [AEAD] built on
Sep
 26 2017 )

 the linux box is configured as a server

 every hour I get this in the logs on server side

 ... client/WINXP:2319 TLS: soft reset sec=0 bytes=19303/67108864
pkts=358/0
 ... client/WINXP:2319 VERIFY OK: depth=1, ###
 ... client/WINXP:2319 VERIFY OK: depth=0, ###
 ... client/WINXP:2319 peer info: IV_VER=2.3.18
 ... client/WINXP:2319 peer info: IV_PLAT=win
 ... client/WINXP:2319 peer info: IV_PROTO=2
 ... client/WINXP:2319 peer info: IV_GUI_VER=OpenVPN_GUI_10
 ... client/WINXP:2319 Outgoing Data Channel: Cipher 'DES-EDE3-CBC'
 initialized with 192 bit key
 ... client/WINXP:2319 WARNING: INSECURE cipher with block size less
than
 128 bit (64 bit). This allows attacks like SWEET32. Mitigate by using a
 --cipher with a larger block size (e.g. AES-256-CBC).
 ... client/WINXP:2319 Outgoing Data Channel: Using 160 bit message hash
 'SHA1' for HMAC authentication
 ... client/WINXP:2319 Incoming Data Channel: Cipher 'DES-EDE3-CBC'
 initialized with 192 bit key
 ... client/WINXP:2319 WARNING: INSECURE cipher with block size less
than
 128 bit (64 bit). This allows attacks like SWEET32. Mitigate by using a
 --cipher with a larger block size (e.g. AES-256-CBC).
 ... client/WINXP:2319 Incoming Data Channel: Using 160 bit message hash
 'SHA1' for HMAC authentication
 ... client/WINXP:2319 Control Channel: TLSv1.2, cipher TLSv1/SSLv3
 ECDHE-RSA-AES256-GCM-SHA384, 2048 bit RSA

 the tunnel works, and both have in its config 'cipher=DES-EDE3-CBC'

 but when I change this cipher= entry to 'cipher=AES-256-CBC' as
mentioned
 in the warning on both sides, it fails to get a connection, why?
 I tested with CAMELLIA, AES, ... ->  no connection;  this 3DES seems
to be
 the only cipher with a block size of more than 64(?) bit, that
works, why?





Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Openvpn-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/openvpn-users

Reply via email to