From: domingo@... (Domingo Alvarez Duarte)
Date: 2002-04-27T05:19:22+09:00
Subject: mod_ruby with mod_ssl segfault the problem and the soluction

Recently I've installed mod_ssl in my apache webserver that is runing
mod_ruby, before that it was working but after that I've starting
geting segfault constantly.
Looking in the web I could see that this problem occurs as well with
mod_perl and php, I did the modifications that the mod_ssl FAQ
indicates but the problem remain there.

Reading about how to use the GDB to debug apache and using it I got
the origin of the sigfault, it was in libcrypto.so that was called
from digest/md5 from ruby.

Looking at the source code I realized that the digest/md5 contains all
code that it needs to perform the encripted hash generation and should
not call libcrypto.so.

Looking in the code of openssl that is used by mod_ssl I saw the
problem:
openssl define the following functions : MD5_Init, MD5_Update,
MD5_Final
and digest/md5 define then as well and when apache is linked with
mod_ssl for some reason digest/md5 is linked against the openssl
functions instead of digest/MD5 functions.

My soluction:
I've edited md5.c, md5.h, md5init.c in digest/md5 and added "rb_" to
all functions that start with MD5 so MD5_Init now is rb_MD5_Init and
so on.

The "rb_" can be any prefix to prevent the name clash with openssl
functions.

Probably with mod_perl and PHP something like that is the problem as
well.

Now my apache webserver works fine.

I hope that this information can be helpfull to someone trying using
mod_ruby and mod_ssl together.

The man is condemned to be free (Jean Paul Sartre).