Re: [Valgrind-users] SSL problems

[Crispin F. <cr...@th...>]

On Fri, 2003-05-23 at 15:22, Steve G wrote:
> Hello,
> 
> I've been doing some testing of daemon's using valgrind.
> I've run across a problem with valgrind and have created a
> simple test program. I've tried several different versions
> of valgrind including cvs.
> 
> I've attached a program that can be compiled as:
> 
> gcc -o ssltest ssltest.c -lcrypto

This is a known problem in openssl. It uses uninitialzed data to
generate random numbers. The dodgy code is in md_rand.c (search for
PURIFY). See:

http://www.mail-archive.com/ope...@op.../msg15497.html

(just for reference, your test program can be shortened as follows
(making use of the very useful VALGRIND_* macros)

#include <openssl/rand.h>
#include <openssl/err.h>
#include <valgrind/memcheck.h>

int main(void)
{
   unsigned char rand_buf[20]; 
                                                                    
   if (!RAND_bytes(rand_buf, sizeof(rand_buf)))
      printf("Couldn't obtain random bytes" );

   VALGRIND_CHECK_READABLE( rand_buf, sizeof( rand_buf ) );
   return 0;
}


Crispin