Hi, The example code that comes with openssl comes with a file 'selfsign.c' which I used to generate a key. I modified the line that calls X509_gmtime_adj to 100 years because I didn't care about key expiry (this is probably the wrong way to do it, but...).
This generated a large negative adjustment, which isn't trapped by the function until it gets to ASN1_GENERALIZEDTIME_set. There, the call to OPENSSL_gmtime fails and is initialised with random junk from the stack - the 'data' variable is passed into this function uninitialised, and if gmtime() fails it just returns it as the result without checking). This random junk is then sprintf()ed into a fixed length buffer of 20 bytes, but the resulting string on my machine is 47 bytes, causing failure of the app a few lines later. It seems that only the Win32 gmtime() returns NULL if its argument is negative... gcc seems to return valid data, however NULL is a valid return value and should be checked for & handled correctly. Tony -- "When I am working on a problem I never think about beauty. I only think about how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -- Buckminster Fuller ______________________________________________________________________ OpenSSL Project http://www.openssl.org Development Mailing List [EMAIL PROTECTED] Automated List Manager [EMAIL PROTECTED]
