Configure Login Audit Rules

# SPDX-FileCopyrightText: 2025 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

# ------------------------------------------------------------------
# METADATA
# ------------------------------------------------------------------

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.130296");
  script_version("2025-11-21T05:40:28+0000");
  script_tag(name:"last_modification", value:"2025-11-21 05:40:28 +0000 (Fri, 21 Nov 2025)");
  script_tag(name:"creation_date", value:"2025-05-07 11:44:17 +0000 (Wed, 07 May 2025)");
  script_tag(name:"cvss_base", value:"0.0");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:H/Au:S/C:N/I:N/A:N");
  script_tag(name:"qod", value:"97");

  script_name("Configure Login Audit Rules");

  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2025 Greenbone AG");
  script_family("Policy");
  script_dependencies("compliance_tests.nasl", "compliance_os_check.nasl");

  script_mandatory_keys("Compliance/Launch", "policy/ssh/login/euleros_openeuler");

  script_xref(name:"Policy", value:"EulerOS Baseline: openEuler Security Configuration Baseline (v1.0.0): 4. Log Audit: 4.1 Audit: 4.1.3 Configure Login Audit Rules (Recommendation)");
  script_xref(name:"Policy", value:"openEuler Baseline: openEuler Security Configuration Baseline (v1.0.0): 4. Log Audit: 4.1 Audit: 4.1.3 Configure Login Audit Rules (Recommendation)");

  script_tag(name:"summary", value:"The /var/log/lastlog file is updated when a user successfully
logs in to the system. Therefore, user login events can be recorded by auditing and monitoring the
file. If login audit is not configured, the administrator cannot trace login events from audit logs.

By default, login audit rules are not configured in openEuler. You are advised to configure rules
based on the actual service scenario.");

  exit(0);
}

include("ssh_func.inc");
include("host_details.inc");
include("policy_reporting_module.inc");

title = "Configure Login Audit Rules";

solution = "Create a rule file, for example, logins.rules, in the /etc/audit/rules.d/ directory
and add audit rules to the file.

# vim /etc/audit/rules.d/logins.rules
-w /var/log/lastlog -p wa -k

Restart the auditd service for the rules to take effect.

# service auditd restart
Stopping logging: [ OK ]
Redirecting start to /bin/systemctl start auditd.service";

check_type = "SSH_Cmd";

action = 'Run the command in the terminal:
# auditctl -l 2>/dev/null | grep -iE "lastlog"';

expected_value = 'The output should not be empty';

# ------------------------------------------------------------------
# CONNECTION CHECK
# ------------------------------------------------------------------

if(!get_kb_item("login/SSH/success") || !sock = ssh_login_or_reuse_connection()){

  report_ssh_error(title: title,
                   solution: solution,
                   action: action,
                   expected_value: expected_value,
                   check_type: check_type);
  exit(0);
}

# ------------------------------------------------------------------
# CHECK : Verify command `auditctl -l | grep -iE "lastlog"`
# ------------------------------------------------------------------

step_cmd = 'auditctl -l 2>/dev/null | grep -iE "lastlog"';
actual_value = ssh_cmd(socket:sock, cmd:step_cmd, return_errors:TRUE, return_linux_errors_only:TRUE);

if(eregmatch(string: actual_value, pattern:"(No such file or directory|Permission denied|Command not found|Segmentation fault|service not found|is not running|syntax error near unexpected token|syntax error: unexpected end of file)", icase: TRUE)){
  compliant = "incomplete";
  comment = "Something went wrong during the audit check. Please try again.";
}else if(actual_value){
  compliant = "yes";
  comment = "Check passed";
}else{
  compliant = "no";
  comment = "Check failed";
}

# ------------------------------------------------------------------
# REPORT
# ------------------------------------------------------------------

target = get_kb_item("policy/ssh/login/os-release");
comment = "Target: " + target + "\n" + comment;

report_audit(action: action,
             actual_value: actual_value,
             expected_value: expected_value,
             is_compliant: compliant,
             solution: solution,
             check_type: check_type,
             title: title,
             comment: comment);

exit(0);