install_psad

install_psad(){
clear
f_banner
echo -e "\e[34m---------------------------------------------------------------------------------------------------------\e[00m"
echo -e "\e[93m[+]\e[00m Install PSAD"
echo -e "\e[34m---------------------------------------------------------------------------------------------------------\e[00m"
echo " PSAD is a piece of Software that actively monitors you Firewall Logs to Determine if a scan
       or attack event is in Progress. It can alert and Take action to deter the Threat

       NOTE:
       IF YOU ARE ONLY RUNNING THIS FUNCTION, YOU MUST ENABLE LOGGING FOR iptables

       iptables -A INPUT -j LOG
       iptables -A FORWARD -j LOG

       "
echo ""
echo "Do you want to install PSAD (Recommended)? y/n " ; read psad_answer
if [ "$psad_answer" == "y" ]; then
     echo "Type an Email Address to Receive PSAD Alerts: " ; read inbox1
     apt-get install psad
     sed s/INBOX/$inbox1/g templates/psad.conf
     sed s/hostname/$host_name.$domain_name/g templates/psad.conf > /etc/psad/psad.conf
     psad --sig-update
     service psad restart
     echo "Installation and Configuration Complete"
     echo "Run service psad status, for detected events"
     echo ""
     say_done
else
     echo "OK"
     say_done
fi
}

La Función install_psad instala la herramienta PSAD. PSAD es una herramienta que monitorea activamente los logs del firewall de Linux para determinar si hay en progreso un escaneo o un ataque. Puede alertar o tomar acción para mitigar el ataque. Se hace una configuración haciendo uso de la plantilla que se encuentra en templates/psad.conf.

#
##############################################################################
#
#  This is the configuration file for psad (the Port Scan Attack Detector).
#  Normally this file gets installed at /etc/psad/psad.conf, but can be put
#  anywhere in the filesystem and then the path can be specified on the
#  command line argument "-c <file>" to psad.  All three psad daemons (psad,
#  kmsgsd, and psadwatchd) reference this config file.
#
#  Each line has the form  "<variable name>    <value>;".  Note the semi-
#  colon after the <value>.  All characters after the semicolon will be
#  ignored to provide space for comments.
#
##############################################################################
#

### Supports multiple email addresses (as a comma separated
### list).
EMAIL_ADDRESSES             INBOX;

### Machine hostname
HOSTNAME                    hostname;

### Specify the home and external networks.  Note that by default the
### ENABLE_INTF_LOCAL_NETS is enabled, so psad automatically detects
### all of the directly connected subnets and uses this information as
### the HOME_NET variable.
HOME_NET                    any;
EXTERNAL_NET                any;

### The FW_SEARCH_ALL variable controls how psad will parse iptables
### messages.  If it is set to "Y" then psad will parse all iptables
### messages for evidence of scan activity.  If it is set to "N" then
### psad will only parse those iptables messages that contain logging
### prefixes specified by the FW_MSG_SEARCH variable below.  Logging
### prefixes are set with the --log-prefix command line option to iptables.
### Setting FW_SEARCH_ALL to "N" is useful for having psad only analyze
### iptables messages that are logged out of a specific iptables chain
### (multiple strings can be searched for, see the comment above the
### FW_MSG_SEARCH variable below) or a specific logging rule for example.
### FW_SEARCH_ALL is set to "Y" by default since usually people want psad
### to parse all iptables messages.
FW_SEARCH_ALL               Y;

### The FW_MSG_SEARCH variable can be modified to look for logging messages
### that are specific to your firewall configuration (specified by the
### "--log-prefix" option.  For example, if your firewall uses the
### string "Audit" for packets that have been blocked, then you could
### set FW_MSG_SEARCH to "Audit";  The default string to search for is
### "DROP".  Both psad and kmsgsd reference this file.  NOTE: You can
### specify this variable multiple times to have psad search for multiple
### strings.  For example to have psad search for the strings "Audit" and
### "Reject", you would use the following two lines:
#FW_MSG_SEARCH               Audit;
#FW_MSG_SEARCH               REJECT;
FW_MSG_SEARCH               DROP;

### Set the type of syslog daemon that is used.  The SYSLOG_DAEMON
### variable accepts four possible values: syslogd, syslog-ng, ulogd,
### or metalog.  Note: this variable is only used if ENABLE_SYSLOG_FILE is
### disabled, and this in turn will mean that the legacy kmsgsd daemon will
### collect firewall logs from syslog via the old named pipe mechanism.
SYSLOG_DAEMON               syslogd;

### What type of interface configuration do you use?  Set this variable to
### "iproute2" if you want to use the iproute2 type configuration.
### iproute2 does not use aliases for multi-homed interfaces and
### ifconfig does not show secondary addresses for multi-homed interfaces.
#IFCFGTYPE  iproute2;
IFCFGTYPE                   ifconfig;

### Danger levels.  These represent the total number of
### packets required for a scan to reach each danger level.
### A scan may also reach a danger level if the scan trips
### a signature or if the scanning ip is listed in
### auto_ips so a danger level is automatically
### assigned.
DANGER_LEVEL1               5;    ### Number of packets.
DANGER_LEVEL2               15;
DANGER_LEVEL3               150;
DANGER_LEVEL4               1500;
DANGER_LEVEL5               10000;

### Set the interval (in seconds) psad will use to sleep before
### checking for new iptables log messages
CHECK_INTERVAL              5;

### Search for snort "sid" values generated by fwsnort
### or snort2iptables
SNORT_SID_STR               SID;

### Set the minimum range of ports that must be scanned before
### psad will send an alert.  The default is 1 so that at
### least two port must be scanned (p2-p1 >= 1).  This can be set
### to 0 if you want psad to be extra paranoid, or 30000 if not.
PORT_RANGE_SCAN_THRESHOLD   1;

### For IP protocol scan detection (nmap -sO).  While it may be relatively
### common for a host to trigger on tcp, udp, and icmp, it is more unusual if
### a host triggers on, say, five different IP protocols
PROTOCOL_SCAN_THRESHOLD     5;

### If "Y", means that scans will never timeout.  This is useful
### for catching scans that take place over long periods of time
### where the attacker is trying to slip beneath the IDS thresholds.
ENABLE_PERSISTENCE          Y;

### This is used only if ENABLE_PERSISTENCE = "N";
SCAN_TIMEOUT                3600;  ### seconds

### Specify how often to timeout old scan data relative to CHECK_INTERVAL
### iterations.  This feature is only used if ENABLE_PERSISTENCE is disabled.
### Note that for psad processes that have tracked a lot of scans, it is
### advisable to leave this threshold at the default value of 5 or greater
### because the scan tracking hash may be quite large.
PERSISTENCE_CTR_THRESHOLD   5;

### Limit the number of src->dst IP pairs that psad will track.  The default
### is zero (i.e. unlimited), but if psad is running on a system with limited
### memory, this can be handy to restrict psad's memory usage.  It is best to
### combine this option with disabling ENABLE_PERSISTENCE so that older scans
### are deleted and therefore newer scans will on average continue to be
### tracked.  A good non-zero value is, say, 50000, but this will vary
### depending on available system memory.
MAX_SCAN_IP_PAIRS           0;

### If "Y", means all signatures will be shown since
### the scan started instead of just the current ones.
SHOW_ALL_SIGNATURES         N;

### Allow reporting methods to be enabled/restricted.  This keyword can
### accept values of "nosyslog" (don't write any messages to syslog),
### "noemail" (don't send any email messages), or "ALL" (to generate both
### syslog and email messages).  "ALL" is the default.  Both "nosyslog"
### and "noemail" can be combined with a comma to disable all logging
### and alerting.
ALERTING_METHODS            ALL;

### By default, psad acquires iptables log data from the /var/log/messages
### file which the local syslog daemon (usually) writes iptables log messages
### to.  If the ENABLE_SYSLOG_FILE variable below is set to "N", then psad
### reconfigures syslog to write iptables log data to the
### /var/lib/psad/psadfifo fifo file where the messages are picked up by kmsgsd
### written to the file /var/log/psad/fwdata for analysis by psad.  On some
### systems, having syslog communicate log data to kmsgsd can be problematic
### (syslog configs and external factors such as Apparmor and SELinux can play
### a role here), so leaving the ENABLE_SYSLOG_FILE variable set to "Y" is
### usually recommended.
ENABLE_SYSLOG_FILE          Y;
IPT_WRITE_FWDATA            Y;
IPT_SYSLOG_FILE             /var/log/syslog;

### When enabled, this instructs psad to write the "msg" field
### associated with Snort rule matches to syslog.
ENABLE_SIG_MSG_SYSLOG       Y;
SIG_MSG_SYSLOG_THRESHOLD    10;
SIG_SID_SYSLOG_THRESHOLD    10;

### TTL values are decremented depending on the number of hops
### the packet has taken before it hits the firewall.  We will
### assume packets will not jump through more than 20 hops on
### average.
MAX_HOPS                    20;

### Do not include any timestamp included within kernel logging
### messages (Ubuntu systems commonly have this)
IGNORE_KERNEL_TIMESTAMP     Y;

### FIXME: try to mitigate the affects of the iptables connection
### tracking bug by ignoring tcp packets that have the ack bit set.
### Read the "BUGS" section of the psad man page.  Note that
### if a packet matches a snort SID generated by fwsnort (see
### http://www.cipherdyne.org/fwsnort/)
### then psad will see it even if the ack bit is set.  See the
### SNORT_SID_STR variable.
IGNORE_CONNTRACK_BUG_PKTS   Y;

### define a set of ports to ignore (this is useful particularly
### for port knocking applications since the knock sequence will
### look to psad like a scan).  This variable may be defined as
### a comma-separated list of port numbers or port ranges and
### corresponding protocol,  For example, to have psad ignore all
### tcp in the range 61000-61356 and udp ports 53 and 5000, use:
### IGNORE_PORTS        tcp/61000-61356, udp/53, udp/5000;
IGNORE_PORTS                NONE;

### allow entire protocols to be ignored.  This keyword can accept
### a comma separated list of protocols.  Each protocol must match
### the protocol that is specified in an iptables log message (case
### insensitively, so both "TCP" or "tcp" is ok).
### IGNORE_PROTOCOL             tcp,udp;
IGNORE_PROTOCOLS            NONE;

### allow packets to be ignored based on interface (this is the
### "IN" interface in iptables logging messages).
IGNORE_INTERFACES           NONE;

### Ignore these specific logging prefixes
IGNORE_LOG_PREFIXES         NONE;

### Minimum danger level a scan must reach before any logging or
### alerting is done.  The EMAIL_ALERT_DANGER_LEVEL variable below
### only refers to email alerts; the MIN_DANGER_LEVEL variable
### applies to everything from email alerts to whether or not the
### IP directory is created within /var/log/psad/.  Hence
### MIN_DANGER_LEVEL should be set less than or equal to the value
### assigned to the EMAIL_ALERT_DANGER_LEVEL variable.
MIN_DANGER_LEVEL            1;

### Only send email alert if danger level >= to this value.
EMAIL_ALERT_DANGER_LEVEL    1;

### Enable detection of malicious activity that is delivered via IPv6.  If
### ip6tables is not logging any traffic, then psad won't know anything
### about IPv6, or this variable can be set to "N" (this would be slightly
### faster if ip6tables isn't logging anything).
ENABLE_IPV6_DETECTION       Y;

### Treat all subnets on local interfaces as part of HOME_NET (this
### means that these networks do not have to be manually defined)
ENABLE_INTF_LOCAL_NETS      Y;

### Include MAC addresses in email alert
ENABLE_MAC_ADDR_REPORTING   N;

### Look for the iptables logging rule (fwcheck_psad is executed)
ENABLE_FW_LOGGING_CHECK     Y;

### Send no more than this number of emails for a single
### scanning source IP.  Note that enabling this feature may cause
### alerts for real attacks to not be generated if an attack is sent
### after the email threshold has been reached for an IP address.
### This is why the default is set to "0".
EMAIL_LIMIT                 0;

### By default, psad maintains a counter for each scanning source address,
### but by enabling this variable psad will maintain email counters for
### each victim address that is scanned as well.
ENABLE_EMAIL_LIMIT_PER_DST  N;

### If "Y", send a status email message when an IP has reached the
### EMAIL_LIMIT threshold.
EMAIL_LIMIT_STATUS_MSG      Y;

### This variable is used to have psad throttle the email alerts it sends,
### and implemented as a per-IP threshold.  That is, if EMAIL_THROTTLE
### is set to "10", then psad will only send 1/10th as many emails for each
### scanning IP as it would have normally.  All other variables also apply,
### so this throttle value is taken into account after everything else.  The
### default of zero means to not apply any throttling.
EMAIL_THROTTLE              0;

### If "Y", send email for all newly logged packets from the same
### source ip instead of just when a danger level increases.
ALERT_ALL                   Y;

### If "Y", then psad will import old scan source ip directories
### as current scans instead of moving the directories into the
### archive directory.
IMPORT_OLD_SCANS            N;

### syslog facility and priority (the defaults are usually ok)
### The SYSLOG_FACILITY variable can be set to one of LOG_LOCAL{0-7}, and
### SYSLOG_PRIORITY can be set to one of LOG_INFO, LOG_DEBUG, LOG_NOTICE,
### LOG_WARNING, LOG_ERR, LOG_CRIT, LOG_ALERT, or LOG_EMERG
SYSLOG_IDENTITY             psad;
SYSLOG_FACILITY             LOG_LOCAL7;
SYSLOG_PRIORITY             LOG_INFO;

### Port thresholds for logging and -S and -A output.
TOP_PORTS_LOG_THRESHOLD     500;
STATUS_PORTS_THRESHOLD      20;

### Signature thresholds for logging and -S and -A output.
TOP_SIGS_LOG_THRESHOLD      500;
STATUS_SIGS_THRESHOLD       50;

### Attackers thresholds for logging and -S and -A output.
TOP_IP_LOG_THRESHOLD        500;
STATUS_IP_THRESHOLD         25;

### Specify how often to log the TOP_* information (i.e. how many
### CHECK_INTERVAL iterations before the data is logged again).
TOP_SCANS_CTR_THRESHOLD     1;

### Send scan logs to dshield.org.  This is disabled by default,
### but is a good idea to enable it (subject to your site security
### policy) since the DShield service helps to track the bad guys.
### For more information visit http://www.dshield.org
ENABLE_DSHIELD_ALERTS       N;

### dshield.org alert email address; this should not be changed
### unless the guys at DShield have changed it.
DSHIELD_ALERT_EMAIL         [email protected];

### Time interval (hours) to send email alerts to dshield.org.
### The default is 6 hours, and cannot be less than 1 hour or
### more than 24 hours.
DSHIELD_ALERT_INTERVAL      6;  ### hours

### If you have a DShield user id you can set it here.  The
### default is "0".
DSHIELD_USER_ID             0;

### If you want the outbound DShield email to appear as though it
### is coming from a particular user address then set it here.
DSHIELD_USER_EMAIL          NONE;

### Threshold danger level for DShield data; a scan must reach this
### danger level before associated packets will be included in an
### alert to DShield.  Note that zero is the default since this
### will allow DShield to apply its own logic to determine what
### constitutes a scan (_all_ iptables log messages will be included
### in DShield email alerts).
DSHIELD_DL_THRESHOLD        0;

### List of servers.  Fwsnort supports the same variable resolution as
#### Snort.
HTTP_SERVERS                $HOME_NET;
SMTP_SERVERS                $HOME_NET;
DNS_SERVERS                 $HOME_NET;
SQL_SERVERS                 $HOME_NET;
TELNET_SERVERS              $HOME_NET;

#### AOL AIM server nets
AIM_SERVERS                 [64.12.24.0/24, 64.12.25.0/24, 64.12.26.14/24, 64.12.28.0/24, 64.12.29.0/24, 64.12.161.0/24, 64.12.163.0/24, 205.188.5.0/24, 205.188.9.0/24];

### Configurable port numbers
HTTP_PORTS                  80;
SHELLCODE_PORTS             !80;
ORACLE_PORTS                1521;

### If this is enabled, then psad will die if a rule in the
### /etc/psad/signatures file contains an unsupported option (otherwise
### a syslog warning will be generated).
ENABLE_SNORT_SIG_STRICT     Y;

### If "Y", enable automated IDS response (auto manages
### firewall rulesets).
ENABLE_AUTO_IDS             N;

### Block all traffic from offending IP if danger
### level >= to this value
AUTO_IDS_DANGER_LEVEL       5;

### Set the auto-blocked timeout in seconds (the default
### is one hour).
AUTO_BLOCK_TIMEOUT          3600;

### Set the auto-blocked timeout in seconds for each danger
### level - zero means to block permanently.  Each of these
### can be set independently
AUTO_BLOCK_DL1_TIMEOUT      $AUTO_BLOCK_TIMEOUT;
AUTO_BLOCK_DL2_TIMEOUT      $AUTO_BLOCK_TIMEOUT;
AUTO_BLOCK_DL3_TIMEOUT      $AUTO_BLOCK_TIMEOUT;
AUTO_BLOCK_DL4_TIMEOUT      $AUTO_BLOCK_TIMEOUT;
AUTO_BLOCK_DL5_TIMEOUT      0;   ### permanent

### Enable regex checking on log prefixes for active response
ENABLE_AUTO_IDS_REGEX       N;

### Only block if the iptables log message matches the following regex
AUTO_BLOCK_REGEX            ESTAB;  ### from fwsnort logging prefixes

### Control whether "renew" auto-block emails get sent.  This is disabled
### by default because lots of IPs could have been blocked, and psad
### should not generate a renew email for each of them.
ENABLE_RENEW_BLOCK_EMAILS   N;

### By setting this variable to N, all auto-blocking emails can be
### suppressed.
ENABLE_AUTO_IDS_EMAILS      Y;

### Enable iptables blocking (only gets enabled if
### ENABLE_AUTO_IDS is also set)
IPTABLES_BLOCK_METHOD       Y;

### Specify chain names to which iptables blocking rules will be
### added with the IPT_AUTO_CHAIN{n} keyword.  There is no limit on the
### number of IPT_AUTO_CHAIN{n} keywords; just increment the {n} number
### to add an additional IPT_AUTO_CHAIN requirement. The format for this
### variable is: <Target>,<Direction>,<Table>,<From_chain>,<Jump_rule_position>, \
###              <To_chain>,<Rule_position>.
### "Target": Can be any legitimate iptables target, but should usually
###           just be "DROP".
### "Direction": Can be "src", "dst", or "both", which correspond to the
###              INPUT, OUTPUT, and FORWARD chains.
### "Table": Can be any iptables table, but the default is "filter".
### "From_chain": Is the chain from which packets will be jumped.
### "Jump_rule_position": Defines the position within the From_chain where
###                       the jump rule is added.
### "To_chain": Is the chain to which packets will be jumped. This is the
###             main chain where psad rules are added.
### "Rule_position": Defines the position where rule are added within the
###                  To_chain.
###
### The following defaults make sense for most installations, but note
### it is possible to include blocking rules in, say, the "nat" table
### using this functionality as well.  The following three lines provide
### usage examples:
#IPT_AUTO_CHAIN1              DROP, src, filter, INPUT, 1, PSAD_BLOCK_INPUT, 1;
#IPT_AUTO_CHAIN2              DROP, dst, filter, OUTPUT, 1, PSAD_BLOCK_OUTPUT, 1;
#IPT_AUTO_CHAIN3              DROP, both, filter, FORWARD, 1, PSAD_BLOCK_FORWARD, 1;
IPT_AUTO_CHAIN1             DROP, src, filter, INPUT, 1, PSAD_BLOCK_INPUT, 1;
IPT_AUTO_CHAIN2             DROP, dst, filter, OUTPUT, 1, PSAD_BLOCK_OUTPUT, 1;
IPT_AUTO_CHAIN3             DROP, both, filter, FORWARD, 1, PSAD_BLOCK_FORWARD, 1;

### Flush all existing rules in the psad chains at psad start time.
FLUSH_IPT_AT_INIT           Y;

### Prerequisite check for existence of psad chains and jump rules
IPTABLES_PREREQ_CHECK       1;

### Enable tcp wrappers blocking (only gets enabled if
### ENABLE_AUTO_IDS is also set)
TCPWRAPPERS_BLOCK_METHOD    N;

### Set the whois timeout
WHOIS_TIMEOUT               60;  ### seconds

### Set the number of times an ip can be seen before another whois
### lookup is issued.
WHOIS_LOOKUP_THRESHOLD      20;

### Use this option to force all whois information to contain ascii-only data.
### Sometime whois information for IP addresses in China and other countries
### can contain non-ascii data.  If this option is enabled, then any non-
### ascii characters will be replaced with "NA".
ENABLE_WHOIS_FORCE_ASCII    N;

### This variable forces all whois lookups to be done against the source IP
### even when they are associated with a directly connected local network.  IT
### is usually a good idea to leave this setting as the default of 'N'.
ENABLE_WHOIS_FORCE_SRC_IP   N;

### Set the number of times an ip can be seen before another dns
### lookup is issued.
DNS_LOOKUP_THRESHOLD        20;

### Enable psad to run an external script or program (use at your
### own risk!)
ENABLE_EXT_SCRIPT_EXEC      N;

### Define an external program to run after a scan is caught.
### Note that the scan source ip can be specified on the command
### line to the external program through the use of the "SRCIP"
### string (along with some appropriate switch for the program).
### Of course this is only useful if the external program knows
### what to do with this information.
### Example:  EXTERNAL_SCRIPT       /path/to/script --ip SRCIP -v;
EXTERNAL_SCRIPT             /bin/true;

### Control execution of EXTERNAL_SCRIPT (only once per IP, or
### every time a scan is detected for an ip).
EXEC_EXT_SCRIPT_PER_ALERT   N;

### Disk usage variables
DISK_CHECK_INTERVAL         300;  ### seconds

### This can be set to 0 to disable disk checking altogether
DISK_MAX_PERCENTAGE         95;

### This can be set to 0 to have psad not place any limit on the
### number of times it will attempt to remove data from
### /var/log/psad/.
DISK_MAX_RM_RETRIES         10;

### Enable archiving of old scan directories at psad startup.
ENABLE_SCAN_ARCHIVE         N;

### Truncate fwdata file at startup
TRUNCATE_FWDATA             Y;

### Only archive scanning IP directories that have reached a danger
### level greater than or equal to this value.  Archiving old
### scanning ip directories only takes place at psad startup.
MIN_ARCHIVE_DANGER_LEVEL    1;

### Email subject line config.  Change these prefixes if you want
### psad to generate email alerts that say something other than
### the following.
MAIL_ALERT_PREFIX           [psad-alert];
MAIL_STATUS_PREFIX          [psad-status];
MAIL_ERROR_PREFIX           [psad-error];
MAIL_FATAL_PREFIX           [psad-fatal];

### URL for getting the latest psad signatures
SIG_UPDATE_URL              http://www.cipherdyne.org/psad/signatures;

### These next two are psadwatchd vars
PSADWATCHD_CHECK_INTERVAL   5;  ### seconds
PSADWATCHD_MAX_RETRIES      10;

### Directories
INSTALL_ROOT                /;
PSAD_DIR                    $INSTALL_ROOT/var/log/psad;
PSAD_RUN_DIR                $INSTALL_ROOT/var/run/psad;
PSAD_FIFO_DIR               $INSTALL_ROOT/var/lib/psad;
PSAD_LIBS_DIR               $INSTALL_ROOT/usr/lib/psad;
PSAD_CONF_DIR               $INSTALL_ROOT/etc/psad;
PSAD_ERR_DIR                $PSAD_DIR/errs;
CONF_ARCHIVE_DIR            $PSAD_CONF_DIR/archive;
SCAN_DATA_ARCHIVE_DIR       $PSAD_DIR/scan_archive;
ANALYSIS_MODE_DIR           $PSAD_DIR/ipt_analysis;
SNORT_RULES_DIR             $PSAD_CONF_DIR/snort_rules;
FWSNORT_RULES_DIR           /etc/fwsnort/snort_rules;  ### may not exist

### Files
FW_DATA_FILE                $PSAD_DIR/fwdata;
ULOG_DATA_FILE              $PSAD_DIR/ulogd.log;
FW_CHECK_FILE               $PSAD_DIR/fw_check;
DSHIELD_EMAIL_FILE          $PSAD_DIR/dshield.email;
SIGS_FILE                   $PSAD_CONF_DIR/signatures;
PROTOCOLS_FILE              $PSAD_CONF_DIR/protocols;
ICMP_TYPES_FILE             $PSAD_CONF_DIR/icmp_types;
ICMP6_TYPES_FILE            $PSAD_CONF_DIR/icmp6_types;
AUTO_DL_FILE                $PSAD_CONF_DIR/auto_dl;
SNORT_RULE_DL_FILE          $PSAD_CONF_DIR/snort_rule_dl;
POSF_FILE                   $PSAD_CONF_DIR/posf;
P0F_FILE                    $PSAD_CONF_DIR/pf.os;
IP_OPTS_FILE                $PSAD_CONF_DIR/ip_options;
PSAD_FIFO_FILE              $PSAD_FIFO_DIR/psadfifo;
ETC_HOSTS_DENY_FILE         /etc/hosts.deny;
ETC_SYSLOG_CONF             /etc/syslog.conf;
ETC_RSYSLOG_CONF            /etc/rsyslog.conf;
ETC_SYSLOGNG_CONF           /etc/syslog-ng/syslog-ng.conf;
ETC_METALOG_CONF            /etc/metalog/metalog.conf;
STATUS_OUTPUT_FILE          $PSAD_DIR/status.out;
ANALYSIS_OUTPUT_FILE        $PSAD_DIR/analysis.out;
INSTALL_LOG_FILE            $PSAD_DIR/install.log;

### PID files
PSAD_PID_FILE               $PSAD_RUN_DIR/psad.pid;
PSAD_CMDLINE_FILE           $PSAD_RUN_DIR/psad.cmd;
KMSGSD_PID_FILE             $PSAD_RUN_DIR/kmsgsd.pid;
PSADWATCHD_PID_FILE         $PSAD_RUN_DIR/psadwatchd.pid;

### List of ips that have been auto blocked by iptables
### or tcpwrappers (the auto blocking feature is disabled by
### default, see the psad man page and the ENABLE_AUTO_IDS
### variable).
AUTO_BLOCK_IPT_FILE         $PSAD_DIR/auto_blocked_iptables;
AUTO_BLOCK_TCPWR_FILE       $PSAD_DIR/auto_blocked_tcpwr;

### File used internally by psad to add iptables blocking
### rules to a running psad process
AUTO_IPT_SOCK               $PSAD_RUN_DIR/auto_ipt.sock;

FW_ERROR_LOG                $PSAD_ERR_DIR/fwerrorlog;
PRINT_SCAN_HASH             $PSAD_DIR/scan_hash;

### /proc interface for controlling ip forwarding
PROC_FORWARD_FILE           /proc/sys/net/ipv4/ip_forward;

### Packet counters for tcp, udp, and icmp protocols
PACKET_COUNTER_FILE         $PSAD_DIR/packet_ctr;

### Top scanned ports
TOP_SCANNED_PORTS_FILE      $PSAD_DIR/top_ports;

### Top signature matches
TOP_SIGS_FILE               $PSAD_DIR/top_sigs;

### Top attackers
TOP_ATTACKERS_FILE          $PSAD_DIR/top_attackers;

### Counter file for Dshield alerts
DSHIELD_COUNTER_FILE        $PSAD_DIR/dshield_ctr;

### Counter file for iptables prefixes
IPT_PREFIX_COUNTER_FILE     $PSAD_DIR/ipt_prefix_ctr;

### iptables command output and error collection files; these are
### used by IPTables::ChainMgr
IPT_OUTPUT_FILE             $PSAD_DIR/psad.iptout;
IPT_ERROR_FILE              $PSAD_DIR/psad.ipterr;

### system binaries
iptablesCmd      /sbin/iptables;
ip6tablesCmd     /sbin/ip6tables;
shCmd            /bin/sh;
wgetCmd          /usr/bin/wget;
gzipCmd          /bin/gzip;
mknodCmd         /bin/mknod;
psCmd            /bin/ps;
mailCmd          /bin/mail;
sendmailCmd      /usr/sbin/sendmail;
ifconfigCmd      /sbin/ifconfig;
ipCmd            /sbin/ip;
killallCmd       /usr/bin/killall;
netstatCmd       /bin/netstat;
unameCmd         /bin/uname;
whoisCmd         $INSTALL_ROOT/usr/bin/whois_psad;
dfCmd            /bin/df;
fwcheck_psadCmd  $INSTALL_ROOT/usr/sbin/fwcheck_psad;
psadwatchdCmd    $INSTALL_ROOT/usr/sbin/psadwatchd;
kmsgsdCmd        $INSTALL_ROOT/usr/sbin/kmsgsd;
psadCmd          $INSTALL_ROOT/usr/sbin/psad;

Para visualizar si PSAD a detectado algo, ejecutamos:

$ service psad status

Veremos algo así:

Status of Port Scan Attack Detector:
[+] psadwatchd (pid: 3219)  %CPU: 0.0  %MEM: 0.0
    Running since: Sun Dec 27 10:03:13 2015

[+] psad (pid: 3213)  %CPU: 2.6  %MEM: 4.9
    Running since: Sun Dec 27 10:03:13 2015
    Command line arguments: [none specified]
    Alert email address(es): [email protected]

[+] Version: psad v2.2.1

[+] Top 50 signature matches:
      "ICMP Destination Unreachable Port Unreachable" (icmp),  Count: 298,  Unique sources: 292,  Sid: 402
      "ICMP PING" (icmp),  Count: 209,  Unique sources: 75,  Sid: 384
      "MISC MS Terminal Server communication attempt" (tcp),  Count: 177,  Unique sources: 95,  Sid: 100077
      "MISC Microsoft SQL Server communication attempt" (tcp),  Count: 161,  Unique sources: 71,  Sid: 100205
      "BACKDOOR DoomJuice file upload attempt" (tcp),  Count: 153,  Unique sources: 14,  Sid: 2375
      "ICMP Destination Unreachable Communication with Destination Host is Administratively Prohibited" (icmp),  Count: 151,  Unique sources: 9,  Sid: 486
      "BACKDOOR win-trin00 connection attempt" (udp),  Count: 62,  Unique sources: 3,  Sid: 1853
      "MISC Radmin Default install options attempt" (tcp),  Count: 62,  Unique sources: 26,  Sid: 100204
      "SCAN UPnP communication attempt" (udp),  Count: 40,  Unique sources: 29,  Sid: 100074
      "MISC VNC communication attempt" (tcp),  Count: 40,  Unique sources: 24,  Sid: 100202
      "ICMP Destination Unreachable Host Unreachable" (icmp),  Count: 37,  Unique sources: 27,  Sid: 399
      "ICMP PING Sun Solaris" (icmp),  Count: 31,  Unique sources: 6,  Sid: 381
      "MISC Microsoft PPTP communication attempt" (tcp),  Count: 24,  Unique sources: 3,  Sid: 100082
      "POLICY HP JetDirect LCD communication attempt" (tcp),  Count: 17,  Unique sources: 5,  Sid: 510
      "MISC PCAnywhere communication attempt" (tcp),  Count: 10,  Unique sources: 4,  Sid: 100073
      "ICMP Destination Unreachable Communication Administratively Prohibited" (icmp),  Count: 8,  Unique sources: 8,  Sid: 485
      "MISC Windows popup spam attempt" (udp),  Count: 8,  Unique sources: 2,  Sid: 100196
      "MISC HP Web JetAdmin communication attempt" (tcp),  Count: 8,  Unique sources: 8,  Sid: 100084
      "ICMP Destination Unreachable Network Unreachable" (icmp),  Count: 5,  Unique sources: 5,  Sid: 401
      "ICMP Destination Unreachable Fragmentation Needed and DF bit was set" (icmp),  Count: 5,  Unique sources: 2,  Sid: 396
      "ICMP redirect host" (icmp),  Count: 3,  Unique sources: 1,  Sid: 472
      "BACKDOOR netbus Connection Cttempt" (tcp),  Count: 2,  Unique sources: 2,  Sid: 100028
      "DOS DB2 dos communication attempt" (tcp),  Count: 2,  Unique sources: 2,  Sid: 1641
      "BACKDOOR Doly 2.0 Connection attempt" (tcp),  Count: 2,  Unique sources: 2,  Sid: 119
      "POLICY vncviewer Java applet communication attempt" (tcp),  Count: 2,  Unique sources: 2,  Sid: 1846
      "ICMP Echo Reply" (icmp),  Count: 2,  Unique sources: 2,  Sid: 408
      "BACKDOOR SatansBackdoor.2.0.Beta, or BackConstruction 2.1 Connection Attempt" (tcp),  Count: 1,  Unique sources: 1,  Sid: 100041
      "ICMP traceroute" (icmp),  Count: 1,  Unique sources: 1,  Sid: 385
      "BACKDOOR GateCrasher Connection attempt" (tcp),  Count: 1,  Unique sources: 1,  Sid: 147

SRC:  103.56.112.170, DL: 2, Dsts: 1, Pkts: 1, Total protocols: 1, Unique sigs: 1, Email alerts: 1

    DST: 23.92.*.*, Local IP
        Scanned ports: TCP 5900, Pkts: 1, Chain: INPUT, Intf: eth0
        Total scanned IP protocols: 1, Chain: INPUT, Intf: eth0
        Signature match: "MISC VNC communication attempt"
            TCP, Chain: INPUT, Count: 1, DP: 5900, SYN, Sid: 100202