[ntp:questions] Failure modes on Windows Server 2008 R2 64-bit

Martin Burnicki martin.burnicki at meinberg.de
Fri Aug 16 12:10:28 UTC 2013

David Taylor wrote:
> On 14/08/2013 04:01, Danny Mayer wrote:
> []
>> NTP doesn't own the OpenSSL sources so we don't distribute it. People
>> can get their own if they want it.

OpenSSL is also not easy to compile from scratch, i.e. you need at least 
some perl interpreter, and assembler if you want fast code.

NTP's VS project files for windows use some environment settings to 
locate the OpenSSL headers and import libs, so you can install a 
precompiled OpenSSL SDK (headers and import libs), set up the 
environment accordingly, and build NTP to use the specified OpenSSL version.

> .. and this what the Meinberg installer does. However, some earlier
> installs have the SSL DLLs in the Windows\System32 directory, which
> means that you may not know whether other software is using them and,
> should they be in use, they can't be replaced with a simple file copy.

Correct, and to my knowledge most problems are if you e.g. built NTP 
against OpenSSL 0.9.8 but have installed 1.0.0 DLLs, or vice versa.

In 2011 I had some email exchange with Harlan and Dave Hart where I 
proposed to link NTP statically against OpenSSL.

Since the libeay32.dll shipped with the installer is installed to the 
NTP directory only this DLL is anyway not shared with some other app, so 
the original idea for a DLL does not apply here.

Also the DLL is always loaded completely into memory, even if only a 
very small number of the exported functions is used.

My proposal was rejected IIRC due ITAR concerns. If these are no 
problems anymore then linking statically would very much avoid DLL 
version problems.

Martin Burnicki

Meinberg Funkuhren
Bad Pyrmont

More information about the questions mailing list