oscap-ssh man page

oscap-ssh — Tool for running oscap over SSH and collecting results.

Description

oscap-ssh runs oscap tool on a remote system through SSH connection. The input files are transfered to the target system and after the scan finishes result files are transfered back. No temporary data remains on the remote machine.

The tool requires bash, ssh, scp and mktemp to perform OVAL and XCCDF evaluation of remote machines. The remote machine also has to have oscap installed and in $PATH. This can be accomplished by installing openscap-scanner.

Usage of the tool mimics usage and options of oscap(8) tool.

Usage

Evaluation of XCCDF content

$ oscap-ssh user@host 22 xccdf eval [options] INPUT_CONTENT

Only source datastreams are supported as INPUT_CONTENT!

Supported options are:
 --profile
 --tailoring-file
 --tailoring-id
 --cpe
 --results
 --results-arf
 --report
 --skip-valid
 --fetch-remote-resources
 --progress
 --datastream-id
 --xccdf-id
 --benchmark-id
 --remediate

Evaluation of OVAL content

$ oscap-ssh user@host 22 oval eval [options] INPUT_CONTENT

Supported options are:
 --id
 --variables
 --directives
 --results
 --report
 --skip-valid
 --datastream-id
 --oval-id

Collection of OVAL System Characteristic

$ oscap-ssh user@host 22 oval collect [options] INPUT_CONTENT

Supported options are:
 --id
 --syschar
 --variables
 --skip-valid

Specific option for oscap-ssh (must be first argument):
 --sudo

Environment variables

oscap-ssh checks out the SSH_ADDITIONAL_OPTIONS environment variable, and pastes its contents into the command-line of ssh to the location where options are expected. Supply the variable in form of a string that corresponds to a section of the ssh command-line and that consists of options you want to pass.

Example Usage

Simple XCCDF evaluation

The following command evaluates a remote Fedora machine as root. HTML report is written out as report.html on the local machine. Can be executed from any machine that has ssh, scp and bash. The local machine does not need to have openscap installed. It also uses the SSH_ADDITIONAL_OPTIONS variable to configure ssh in such way that contents of the known_hosts file are ignored.

$ export SSH_ADDITIONAL_OPTIONS="-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null" $ oscap-ssh root@192.168.1.13 22 xccdf eval --profile xccdf_org.ssgproject.content_profile_common --report report.html /usr/share/xml/scap/ssg/content/ssg-fedora-ds.xml

XCCDF Evaluation with tailoring file

The following command uses a tailoring file and also copies back ARF and XCCDF results. The tailoring file is automatically copied from local machine to remote.

$ oscap-ssh --sudo oscap-user@192.168.1.13 22 xccdf eval --profile xccdf_org.ssgproject.content_profile_common --report report.html --results results.xml --results-arf arf.xml --tailoring-file ssg-fedora-ds-tailoring.xml /usr/share/xml/scap/ssg/content/ssg-fedora-ds.xml

Running remotely as root

Note that the openscap scanner is best run by the 'root' user as in the first example above. To do this, the "PermitRootLogin" directive must be enabled in /etc/ssh/sshd_config, which is itself a security violation. A safer approach is to enable a non-privileged user ('oscap-user' in the second example above) to run only the oscap binary as root (with the '--sudo' flag) by updating the remote machine's 'sudoers' file or adding a file like /etc/sudoers.d/99-oscap-user:
 # allow oscap-user to run openscap scanner
 Defaults!/usr/bin/oscap !requiretty
 oscap-user ALL=(root) NOPASSWD: /usr/bin/oscap

Reporting Bugs

Please report bugs using https://github.com/OpenSCAP/openscap/issues

Authors

Martin Preisler <mpreisle@redhat.com>
Šimon Lukašík <slukasik@redhat.com>

Info

January 2016 Red Hat, Inc. System Administration Utilities