Do Not Install the TFTP Client

# 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("1.3.6.1.4.1.25623.1.0.130447");
  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 11:45:56 +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("Do Not Install the TFTP Client");

  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_eulerosvirtual_openeuler");

  script_xref(name:"Policy", value:"EulerOS Baseline: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.2 Do Not Install the TFTP Client (Requirement)");
  script_xref(name:"Policy", value:"EulerOS Virtual: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.2 Do Not Install the TFTP Client (Requirement)");
  script_xref(name:"Policy", value:"openEuler Baseline: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.2 Do Not Install the TFTP Client (Requirement)");

  script_tag(name:"summary", value:"Trivial File Transfer Protocol (TFTP) is used for file transfer
between a Linux server and other servers, desktop systems, as well as terminal devices. TFTP does
not support authentication and encryption mechanisms. Data tends to be forged, tampered with, or
stolen by attackers during communication. Therefore, do not install the TFTP service and TFTP
clients. Devices without a TFTP client and service cannot provide TFTP service or use the TFTP
client to communicate with external devices. If files need to be transferred, SFTP can be used
instead.");

  exit(0);
}

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

title = "Do Not Install the TFTP Client";

solution = "If the TFTP software has been installed, run the yum or dnf command to uninstall it.

# yum remove tftp tftp-server

Or

# dnf remove tftp tftp-server";

check_type = "SSH_Cmd";

action = 'Run the command in the terminal:
# rpm -q "tftp"';

expected_value = 'The output should be equal to "package tftp is not installed"';

# ------------------------------------------------------------------
# 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 : Check if the tftp package installed
# ------------------------------------------------------------------

step_cmd = 'rpm -q "tftp"';
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 == 'package tftp is not installed'){
  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);