# @summary
#   Installs and configures `mod_security`.
# 
# @param version
#   Manage mod_security or mod_security2
#
# @param logroot
#   Configures the location of audit and debug logs.
# 
# @param crs_package
#   Name of package that installs CRS rules.
# 
# @param activated_rules
#   An array of rules from the modsec_crs_path or absolute to activate via symlinks.
# 
# @param modsec_dir
#   Defines the path where Puppet installs the modsec configuration and activated rules links.
# 
# @param modsec_secruleengine
#   Configures the rules engine.
# 
# @param audit_log_relevant_status
#   Configures which response status code is to be considered relevant for the purpose of audit logging.
# 
# @param audit_log_parts
#   Defines which parts of each transaction are going to be recorded in the audit log. Each part is assigned a single letter; when a
#   letter appears in the list then the equivalent part will be recorded.
# 
# @param secpcrematchlimit
#   Sets the match limit in the PCRE library.
# 
# @param secpcrematchlimitrecursion
#   Sets the match limit recursion in the PCRE library.
# 
# @param allowed_methods
#   A space-separated list of allowed HTTP methods.
# 
# @param content_types
#   A list of one or more allowed MIME types.
# 
# @param restricted_extensions
#   A space-sparated list of prohibited file extensions.
# 
# @param restricted_headers
#   A list of restricted headers separated by slashes and spaces.
# 
# @param secdefaultaction
#   Defines the default list of actions, which will be inherited by the rules in the same configuration context.
# 
# @param anomaly_score_blocking
#   Activates or deactivates the Collaborative Detection Blocking of the OWASP ModSecurity Core Rule Set.
# 
# @param inbound_anomaly_threshold
#   Sets the scoring threshold level of the inbound blocking rules for the Collaborative Detection Mode in the OWASP ModSecurity Core Rule Set.
# 
# @param outbound_anomaly_threshold
#   Sets the scoring threshold level of the outbound blocking rules for the Collaborative Detection Mode in the OWASP ModSecurity Core Rule Set.
# 
# @param critical_anomaly_score
#   Sets the Anomaly Score for rules assigned with a critical severity.
# 
# @param error_anomaly_score
#   Sets the Anomaly Score for rules assigned with a error severity.
# 
# @param warning_anomaly_score
#   Sets the Anomaly Score for rules assigned with a warning severity.
# 
# @param notice_anomaly_score
#   Sets the Anomaly Score for rules assigned with a notice severity.
# 
# @param secrequestmaxnumargs
#   Sets the maximum number of arguments in the request.
# 
# @param secrequestbodylimit
#   Sets the maximum request body size ModSecurity will accept for buffering.
# 
# @param secrequestbodynofileslimit
#   Configures the maximum request body size ModSecurity will accept for buffering, excluding the size of any files being transported 
#   in the request.
# 
# @param secrequestbodyinmemorylimit
#   Configures the maximum request body size that ModSecurity will store in memory.
# 
# @param manage_security_crs
#   Toggles whether to manage ModSecurity Core Rule Set 
#
# @see https://github.com/SpiderLabs/ModSecurity/wiki for additional documentation.
#
class apache::mod::security (
  $logroot                    = $::apache::params::logroot,
  $version                     = $::apache::params::modsec_version,
  $crs_package                 = $::apache::params::modsec_crs_package,
  $activated_rules             = $::apache::params::modsec_default_rules,
  $modsec_dir                  = $::apache::params::modsec_dir,
  $modsec_secruleengine        = $::apache::params::modsec_secruleengine,
  $audit_log_relevant_status   = '^(?:5|4(?!04))',
  $audit_log_parts             = $::apache::params::modsec_audit_log_parts,
  $secpcrematchlimit           = $::apache::params::secpcrematchlimit,
  $secpcrematchlimitrecursion  = $::apache::params::secpcrematchlimitrecursion,
  $allowed_methods             = 'GET HEAD POST OPTIONS',
  $content_types               = 'application/x-www-form-urlencoded|multipart/form-data|text/xml|application/xml|application/x-amf',
  $restricted_extensions       = '.asa/ .asax/ .ascx/ .axd/ .backup/ .bak/ .bat/ .cdx/ .cer/ .cfg/ .cmd/ .com/ .config/ .conf/ .cs/ .csproj/ .csr/ .dat/ .db/ .dbf/ .dll/ .dos/ .htr/ .htw/ .ida/ .idc/ .idq/ .inc/ .ini/ .key/ .licx/ .lnk/ .log/ .mdb/ .old/ .pass/ .pdb/ .pol/ .printer/ .pwd/ .resources/ .resx/ .sql/ .sys/ .vb/ .vbs/ .vbproj/ .vsdisco/ .webinfo/ .xsd/ .xsx/',
  $restricted_headers          = '/Proxy-Connection/ /Lock-Token/ /Content-Range/ /Translate/ /via/ /if/',
  $secdefaultaction            = 'deny',
  $anomaly_score_blocking      = 'off',
  $inbound_anomaly_threshold   = '5',
  $outbound_anomaly_threshold  = '4',
  $critical_anomaly_score      = '5',
  $error_anomaly_score         = '4',
  $warning_anomaly_score       = '3',
  $notice_anomaly_score        = '2',
  $secrequestmaxnumargs        = '255',
  $secrequestbodylimit         = '13107200',
  $secrequestbodynofileslimit  = '131072',
  $secrequestbodyinmemorylimit = '131072',
  $manage_security_crs         = true,
) inherits ::apache::params {
  include ::apache

  $_secdefaultaction = $secdefaultaction ? {
    /log/   => $secdefaultaction, # it has log or nolog,auditlog or log,noauditlog
    default => "${secdefaultaction},log",
  }

  if $::osfamily == 'FreeBSD' {
    fail('FreeBSD is not currently supported')
  }

  if ($::osfamily == 'Suse' and $::operatingsystemrelease < '11') {
    fail('SLES 10 is not currently supported.')
  }

  case $version {
    1: {
      $mod_name = 'security'
      $mod_conf_name = 'security.conf'
    }
    2: {
      $mod_name = 'security2'
      $mod_conf_name = 'security2.conf'
    }
    default: {
      fail('Unsuported version for mod security')
    }
  }
  ::apache::mod { $mod_name:
    id  => 'security2_module',
    lib => 'mod_security2.so',
  }


  ::apache::mod { 'unique_id_module':
    id  => 'unique_id_module',
    lib => 'mod_unique_id.so',
  }

  if $crs_package  {
    package { $crs_package:
      ensure => 'installed',
      before => [
        File[$::apache::confd_dir],
        File[$modsec_dir],
      ],
    }
  }

  # Template uses:
  # - logroot
  # - $modsec_dir
  # - $audit_log_parts
  # - secpcrematchlimit
  # - secpcrematchlimitrecursion
  # - secrequestbodylimit
  # - secrequestbodynofileslimit
  # - secrequestbodyinmemorylimit
  file { 'security.conf':
    ensure  => file,
    content => template('apache/mod/security.conf.erb'),
    mode    => $::apache::file_mode,
    path    => "${::apache::mod_dir}/${mod_conf_name}",
    owner   => $::apache::params::user,
    group   => $::apache::params::group,
    require => Exec["mkdir ${::apache::mod_dir}"],
    before  => File[$::apache::mod_dir],
    notify  => Class['apache::service'],
  }

  file { $modsec_dir:
    ensure  => directory,
    owner   => 'root',
    group   => 'root',
    mode    => '0755',
    purge   => true,
    force   => true,
    recurse => true,
    require => Package['httpd'],
  }

  file { "${modsec_dir}/activated_rules":
    ensure  => directory,
    owner   => $::apache::params::user,
    group   => $::apache::params::group,
    mode    => '0555',
    purge   => true,
    force   => true,
    recurse => true,
    notify  => Class['apache::service'],
  }

  if $manage_security_crs {
    # Template uses:
    # - $_secdefaultaction
    # - $critical_anomaly_score
    # - $error_anomaly_score
    # - $warning_anomaly_score
    # - $notice_anomaly_score
    # - $inbound_anomaly_threshold
    # - $outbound_anomaly_threshold
    # - $anomaly_score_blocking
    # - $allowed_methods
    # - $content_types
    # - $restricted_extensions
    # - $restricted_headers
    # - $secrequestmaxnumargs
    file { "${modsec_dir}/security_crs.conf":
      ensure  => file,
      content => template('apache/mod/security_crs.conf.erb'),
      require => File[$modsec_dir],
      notify  => Class['apache::service'],
    }

    # Debian 9 has a different rule setup
    unless $::operatingsystem == 'SLES' or ($::operatingsystem == 'Debian' and versioncmp($::operatingsystemrelease, '9') >= 0) or ($::operatingsystem == 'Ubuntu' and versioncmp($::operatingsystemrelease, '18.04') >= 0) {
      apache::security::rule_link { $activated_rules: }
    }
  }
}