Technology Insights

JTR – John The Ripper Compile Error – sha.h:4:25: fatal error: openssl/sha.h: No such file or directory

Earlier while compiling JTR or John The Ripper password cracker on a new Ubuntu 12.04 LTS server I received a compile error. The error compiling JTR, which is noted in more detail below, pointed to the sha.h file not being found which likely means there is a missing package though I have seen other causes for file versions being incorrect. Below I explain the initial compile error in more detail, how to track down the package that provides the necessary file or files, and how to install the necessary package on Ubuntu.

Information Security

Check Linux Server For Rootkits, Check If CentOS Linux Server Is Compromised

Yesterday I wrote an article about securing your /tmp and /var/tmp directories on a Linux server because I had found some files uploaded to the /tmp directory via the apache user. After locking down those directories I wanted to verify that there were no other issues on the server so I installed Rootkit Hunter and Rootcheck which are two applications that will assist you with verifying the integrity of your Linux server. Below is information on installing Rootkit Hunter and Rootcheck as well as information on how to use each of them effectively.

Technology Insights

VSFTPD Error: GnuTLS error -9: A TLS packet with unexpected length was received.

I was tasked with configuring VSFTPD to allow SFTP or FTPES (FTP over explicit TLS/SSL) tonight for a client. The configuration already had regular FTP working which I verified using FileZilla as an FTP client. I was able to login and transfer files in both directions to and from the server. Next I verified that SFTP worked without issue and I was able to also transfer files in both directions using SFTP. For FTPES I had to make some changes and once I did make the changes I was still getting an error when attempting to do a directory listing using FileZilla. Below I describe the initial changes I made to vsftpd.conf, the errors I received attempting to connect with FTPES, and the way I resolved the problem.