Wednesday, 29 January 2014

AIDE Installation and Configuration on Centos

AIDE stands for Advance Intrustion Detection Environment. AIDE  is a file and directory integrity checker.

AIDE Installation

I installed aide using yum command

[root@mail-server ~]# yum install aide

Loaded plugins: fastestmirror, security
Loading mirror speeds from cached hostfile
epel/metalink                                            | 5.4 kB     00:00    
 * base:
 * epel:
 * extras:
 * updates:
base                                                                                                                                             | 3.7 kB     00:00    
extras                                                                                                                                           | 3.4 kB     00:00    
updates                                                                                                                                          | 3.4 kB     00:00    
updates/primary_db                                                                                                                               | 1.4 MB     00:07    
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package aide.x86_64 0:0.14-3.el6_2.2 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

 Package                              Arch                                   Version                                         Repository                            Size
 aide                                 x86_64                                 0.14-3.el6_2.2                                  base                                 123 k

Transaction Summary
Install       1 Package(s)

Total download size: 123 k
Installed size: 297 k
Is this ok [y/N]: y
Downloading Packages:aide-0.14-3.el6_2.2.x86_64.rpm                                                                                                                   | 123 kB     00:01    
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : aide-0.14-3.el6_2.2.x86_64                                                                                                                           1/1
  Verifying  : aide-0.14-3.el6_2.2.x86_64                                                                                                                           1/1

  aide.x86_64 0:0.14-3.el6_2.2                                                                                                                                         

[root@mail-server ~]#

Otherwise you can download and Install from this link


I copped aide.conf for testing purpose from main configuration file /etc/aide.conf

[root@mail-server ~]# cp /etc/aide.conf /root/

[root@mail-server ~]# cat /root/aide.conf

# Example configuration file for AIDE.

@@define DBDIR /var/lib/aide   ---->  This is the Database directory (you can change the directory path )
@@define LOGDIR /var/log/aide 

---->  This is the Log directory (you can change the log path )
# The location of the database to be read.

# The location of the database to be written. #database_out=sql:host:port:database:login_name:passwd:table

# Whether to gzip the output to database

# Default.

#NOT IMPLEMENTED report_url=syslog:LOG_AUTH

# These are the default rules.
#p:      permissions
#i:      inode:
#n:      number of links
#u:      user
#g:      group
#s:      size
#b:      block count
#m:      mtime
#a:      atime
#c:      ctime
#S:      check for growing size
#acl:           Access Control Lists
#selinux        SELinux security context
#xattrs:        Extended file attributes
#md5:    md5 checksum
#sha1:   sha1 checksum
#sha256:        sha256 checksum
#sha512:        sha512 checksum
#rmd160: rmd160 checksum
#tiger:  tiger checksum

#haval:  haval checksum (MHASH only)
#gost:   gost checksum (MHASH only)
#crc32:  crc32 checksum (MHASH only)
#whirlpool:     whirlpool checksum (MHASH only)

#R:             p+i+n+u+g+s+m+c+acl+selinux+xattrs+md5
#L:             p+i+n+u+g+acl+selinux+xattrs
#E:             Empty group
#>:             Growing logfile p+u+g+i+n+S+acl+selinux+xattrs

# You can create custom rules like this.
# With MHASH...
# ALLXTRAHASHES = sha1+rmd160+sha256+sha512+whirlpool+tiger+haval+gost+crc32
ALLXTRAHASHES = sha1+rmd160+sha256+sha512+tiger
# Everything but access time (Ie. all changes)

# Sane, with multiple hashes
# NORMAL = R+rmd160+sha256+whirlpool
NORMAL = R+rmd160+sha256

# For directories, don't bother doing hashes
DIR = p+i+n+u+g+acl+selinux+xattrs

# Access control only
PERMS = p+i+u+g+acl+selinux

# Logfile are special, in that they often change
LOG = >

# Just do md5 and sha256 hashes
LSPP = R+sha256

# Some files get updated automatically, so the inode/ctime/mtime change
# but we want to know when the data inside them changes
DATAONLY =  p+n+u+g+s+acl+selinux+xattrs+md5+sha256+rmd160+tiger

# Next decide what directories/files you want in the database.
# I removed all the below rules. I added only /etc directory
/etc    NORMAL    

I initialized the AIDE database using below command

[root@mail-server ~]# aide --init --config=/root/aide.conf

AIDE, version 0.14

### AIDE database at /var/lib/aide/ initialized.

[root@mail-server ~]#

Then copy the first time initialized database because next time aide to be read this database.

[root@mail-server ~]# cp /var/lib/aide/ /var/lib/aide/aide.db.gz

/var/lib/aide/  ---> AIDE to be written
/var/lib/aide/aide.db.gz          ---> AIDE to be read

First time AIDE checking
 [root@mail-server ~]# aide -c /root/aide.conf --check

AIDE, version 0.14

### All files match AIDE database. Looks okay!

[root@mail-server ~]#

Now i created one file inside /etc directory for testing

[root@mail-server ~]# touch /etc/test.txt
I checked AIDE next time.It gave the created file details.It is like below

[root@mail-server ~]# aide -c /root/aide.conf --check

AIDE found differences between database and filesystem!!
Start timestamp: 2014-01-29 23:08:25

  Total number of files:    2079
  Added files:            0
  Removed files:        0
  Changed files:        1
Changed files:
changed: /etc/test.txt

Detailed information about changes:

File: /etc/test.txt
  Mtime    : 2014-01-29 22:32:36              , 2014-01-29 23:08:20
  Ctime    : 2014-01-29 22:32:36              , 2014-01-29 23:08:20
[root@mail-server ~]#

Thursday, 23 January 2014

Another MySQL daemon already running with the same unix socket. mysqld failed

Today i restarted mysql service in my machine. It stopped but not starting

[root@backup-server ~]# service mysqld stop
Stopping mysqld:                                           [  OK  ]

[root@backup-server ~]# service mysqld start
Another MySQL daemon already running with the same unix socket.
Starting mysqld:                                           [FAILED]

Just I rename the mysql.sock file after that it is working fine.

[root@backup-server ~]# mv /var/lib/mysql/mysql.sock /var/lib/mysq /mysql.sock.bak

[root@backup-server ~]# service mysqld start
Starting mysqld:                                           [  OK  ]

My issue resolved...

Sunday, 12 January 2014

Ignore a specific alert for specific IP address in Snort

If we want to ignore a specific snort rule for specific IP or network, we can use "suppression" in threshold.conf file under /etc/snort.

[root@snort rules]# vim /etc/snort/threshold.conf