Re: RAND_bytes() causes 50% CPU load program crash when using CAPI engine
On 7/25/2012 3:01 PM, Florian Rüchel wrote: Hi, I have a tool which calls RAND_bytes() for a length of 16 bytes while using the CAPI engine and having set it to be used for all purposes. If I run it in my Visual Studio Debugger in executes perfectly, but if run from within a command shell, it hangs on this statement (I localized it with printf statements). Now I am wondering what might be causing this problem. Here is my system: Windows 7 x64 Enterprise cl: Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 16.00.30319.01 for 80x86 link: Microsoft (R) Incremental Linker Version 10.00.30319.01 OpenSSL was compiled with this toolset and so is this program. I cannot reproduce this problem, i.e. creating a small sample program works perfectly. And since I cannot even debug it, I can't limit or search for the problem. Any ideas why this might be caused and how I can track it down? Try putting printf() statements inside RAND_bytes() to narrow it further (I assume you compile OpenSSL yourself). Enjoy Jakob -- Jakob Bohm, CIO, Partner, WiseMo A/S. http://www.wisemo.com Transformervej 29, 2730 Herlev, Denmark. Direct +45 31 13 16 10 This public discussion message is non-binding and may contain errors. WiseMo - Remote Service Management for PCs, Phones and Embedded __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Re: RAND_bytes() causes 50% CPU load program crash when using CAPI engine
On Wed 25/07/12 2:16 PM , Jakob Bohm jb-open...@wisemo.com sent: On 7/25/2012 3:01 PM, Florian Rüchel wrote: Hi, I have a tool which calls RAND_bytes() for a length of 16 bytes while using the CAPI engine and having set it to be used for all purposes. If I run it in my Visual Studio Debugger in executes perfectly, but if run from within a command shell, it hangs on this statement (I localized it with printf statements). Now I am wondering what might be causing this problem. I cannot reproduce this problem, i.e. creating a small sample program works perfectly. And since I cannot even debug it, I can't limit or search for the problem. Any ideas why this might be caused and how I can track it down? Try putting printf() statements inside RAND_bytes() to narrow it further (I assume you compile OpenSSL yourself). Further to Jakob's response - I believe that one of the things RAND_bytes may do is traverse heaps to gather additional entropy. I would ensure that you have no heap corruption too - use gflags and/or other tools to validate your process too. That could possibly explain why the sample program will not reproduce the issue. Carl __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Re: RAND_bytes() causes 50% CPU load program crash when using CAPI engine
Hi, thanks for your responses. It seems this may actually be a heap corruption after all, as the following function causes the crash: `heap_first(hentry,hlist.th32ProcessID,hlist.th32HeapID)` on line 521 with version 1.0.1 I will investigate this further tomorrow and hopefully come up with some explanation. Regards, Florian On 25.07.2012 16:41, carlyo...@keycomm.co.uk wrote: On Wed 25/07/12 2:16 PM , Jakob Bohm jb-open...@wisemo.com sent: On 7/25/2012 3:01 PM, Florian Rüchel wrote: Hi, I have a tool which calls RAND_bytes() for a length of 16 bytes while using the CAPI engine and having set it to be used for all purposes. If I run it in my Visual Studio Debugger in executes perfectly, but if run from within a command shell, it hangs on this statement (I localized it with printf statements). Now I am wondering what might be causing this problem. I cannot reproduce this problem, i.e. creating a small sample program works perfectly. And since I cannot even debug it, I can't limit or search for the problem. Any ideas why this might be caused and how I can track it down? Try putting printf() statements inside RAND_bytes() to narrow it further (I assume you compile OpenSSL yourself). Further to Jakob's response - I believe that one of the things RAND_bytes may do is traverse heaps to gather additional entropy. I would ensure that you have no heap corruption too - use gflags and/or other tools to validate your process too. That could possibly explain why the sample program will not reproduce the issue. Carl __ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
