the-bastion/bin/helper/osh-accountPIV
Stéphane Lesimple 1676979913 feat: add PIV keys support and policy enforcement
A new global option 'ingressRequirePIV' was added, to enable or disable a
bastion-wide policy forcing everybody to use only PIV keys.
2021-01-12 12:05:06 +01:00

208 lines
7.4 KiB
Perl
Executable file

#! /usr/bin/perl -T
# vim: set filetype=perl ts=4 sw=4 sts=4 et:
# NEEDGROUP osh-accountPIV
# SUDOERS # modify PIV policy of an account
# SUDOERS %osh-accountPIV ALL=(allowkeeper) NOPASSWD:/usr/bin/env perl -T /opt/bastion/bin/helper/osh-accountPIV --step 1 --account *
# SUDOERS %osh-accountPIV ALL=(%bastion-users) NOPASSWD:/usr/bin/env perl -T /opt/bastion/bin/helper/osh-accountPIV --step 2 --account *
# FILEMODE 0755
# FILEOWN 0 0
#>HEADER
use common::sense;
use Getopt::Long;
use File::Basename;
use lib dirname(__FILE__) . '/../../lib/perl';
use OVH::Bastion;
use OVH::Result;
local $| = 1;
#
# Globals
#
$ENV{'PATH'} = '/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin:/usr/pkg/bin';
my ($self) = $ENV{'SUDO_USER'} =~ m{^([a-zA-Z0-9._-]+)$};
if (not defined $self) {
if ($< == 0) {
$self = 'root';
}
else {
HEXIT('ERR_SUDO_NEEDED', msg => 'This command must be run under sudo');
}
}
# Fetch command options
Getopt::Long::Configure("no_auto_abbrev");
my $fnret;
my ($result, @optwarns);
my ($account, $policy, $ttl, $step);
eval {
local $SIG{__WARN__} = sub { push @optwarns, shift };
$result = GetOptions(
"account=s" => sub { $account //= $_[1] },
"policy=s" => sub { $policy //= $_[1] },
"step=i" => sub { $step //= $_[1] },
"ttl=i" => sub { $ttl //= $_[1] },
);
};
if ($@) { die $@ }
if (!$result) {
local $" = ", ";
HEXIT('ERR_BAD_OPTIONS', msg => "Error parsing options: @optwarns");
}
if (!$account || !$policy || !$step) {
HEXIT('ERR_MISSING_PARAMETER', msg => "Missing argument 'account' or 'modify' or 'step'");
}
#<HEADER
#>PARAMS:ACCOUNT
$fnret = OVH::Bastion::is_bastion_account_valid_and_existing(account => $account, localOnly => 1);
$fnret or HEXIT($fnret);
# get returned untainted value
$account = $fnret->value->{'account'};
#<PARAMS:ACCOUNT
#>PARAMS:POLICY
if (not grep { $policy eq $_ } qw{ default enforce grace never }) {
HEXIT('ERR_INVALID_PARAMETER', "Expected either 'default,' enforce', 'grace' or 'never' as a parameter to --policy");
}
#<PARAMS:POLICY
#>PARAMS:TTL
if ($policy eq 'grace' && !defined $ttl) {
HEXIT('ERR_MISSING_PARAMETER', "The use of 'grace' requires to specify the --ttl parameter as well");
}
#<PARAMS:TTL
#>PARAMS:STEP
if ($step ne '1' && $step ne '2') {
HEXIT('ERR_INVALID_PARAMETER', "Only 1 or 2 are allowed for --step");
}
#<PARAMS:STEP
#>RIGHTSCHECK
if ($self eq 'root') {
osh_debug "Real root, skipping checks of permissions";
}
$fnret = OVH::Bastion::is_user_in_group(user => $self, group => "osh-accountPIV");
if (!$fnret) {
HEXIT('ERR_SECURITY_VIOLATION', msg => "You're not allowed to run this, dear $self");
}
if (OVH::Bastion::is_admin(account => $account, sudo => 1) && !OVH::Bastion::is_admin(account => $self, sudo => 1)) {
HEXIT('ERR_SECURITY_VIOLATION', msg => "You can't modify the account of an admin without being admin yourself");
}
#<RIGHTSCHECK
#>CODE
$fnret = OVH::Bastion::account_config(account => $account, key => OVH::Bastion::OPT_ACCOUNT_INGRESS_PIV_POLICY, public => 1);
# no file means the policy is 'default' (we can also have a file with a written policy of 'default', it's the same)
my $currentPolicy = $fnret ? $fnret->value : 'default';
# 'yes' is an old synonym of 'enforce'
$currentPolicy = 'enforce' if $currentPolicy eq 'yes';
$fnret = OVH::Bastion::account_config(account => $account, key => OVH::Bastion::OPT_ACCOUNT_INGRESS_PIV_GRACE, public => 1);
my $currentGrace = $fnret ? $fnret->value : 0;
if ($step == 1) {
# step1: we're run under allowkeeper user, set the account config
if ($policy ne 'grace') {
# is the policy we're asked to apply already the current one?
if ($currentPolicy eq $policy) {
HEXIT('OK_NO_CHANGE', msg => "PIV policy was already set to '$policy' for this account, no change needed");
}
# no, ok: apply the requested policy
$fnret = OVH::Bastion::account_config(account => $account, key => OVH::Bastion::OPT_ACCOUNT_INGRESS_PIV_POLICY, public => 1, value => $policy);
if (!$fnret) {
warn_syslog("Couldn't apply the requested PIV policy '$policy' (current is '$currentPolicy'): " . $fnret->msg);
HEXIT($fnret);
}
else {
$fnret = OVH::Bastion::syslogFormatted(
severity => 'info',
type => 'account',
fields => [[action => 'modify'], [account => $account], [item => 'piv_policy'], [old => $currentPolicy], [new => $policy]]
);
}
# and delete any existing grace
if ($currentGrace) {
$fnret = OVH::Bastion::account_config(account => $account, key => OVH::Bastion::OPT_ACCOUNT_INGRESS_PIV_GRACE, public => 1, delete => 1);
if (!$fnret) {
warn_syslog("Couldn't remove the grace TTL PIV policy: " . $fnret->msg);
# attempt to continue nevertheless...
}
else {
my $human = OVH::Bastion::duration2human(seconds => ($currentGrace - time()))->value;
$fnret = OVH::Bastion::syslogFormatted(
severity => 'info',
type => 'account',
fields => [
[action => 'modify'],
[account => $account],
[item => 'piv_grace'],
[old => 'true'],
[new => 'false'],
[comment => "PIV grace up to " . $human->{'human'} . " has been removed"]
]
);
}
}
HEXIT('OK', msg => "PIV policy set to '$policy' for this account");
}
else {
# grace is not really a policy per se, it just sets a grace period for which the account will behave as it had the "never" policy set
$fnret = OVH::Bastion::account_config(account => $account, key => OVH::Bastion::OPT_ACCOUNT_INGRESS_PIV_GRACE, public => 1, value => (time() + $ttl));
if (!$fnret) {
warn_syslog("Couldn't apply the requested grace ttl PIV policy: " . $fnret->msg);
HEXIT($fnret);
}
my $human = OVH::Bastion::duration2human(seconds => $ttl)->value;
$fnret = OVH::Bastion::syslogFormatted(
severity => 'info',
type => 'account',
fields => [
[action => 'modify'],
[account => $account],
[item => 'piv_grace'],
[old => 'false'],
[new => 'true'],
[comment => "PIV grace up to " . $human->{'human'} . " has been set"]
]
);
HEXIT('OK', msg => "PIV grace up to " . $human->{'human'} . " has been set for this account");
}
}
elsif ($step == 2) {
# step2: now we're running under the own account's user, modify the authkeys file accordingly
my $pivAction = (OVH::Bastion::is_effective_piv_account_policy_enabled(account => $account)->is_ok) ? 'enable' : 'disable';
$fnret = OVH::Bastion::ssh_ingress_keys_piv_apply(action => $pivAction, account => $account);
$fnret or HEXIT($fnret);
if ($pivAction eq 'enable') {
HEXIT('OK', msg => "All non-PIV account's ingress keys have been disabled");
}
else {
HEXIT('OK', msg => "Non-PIV account's ingress keys, if any, have been restored");
}
}
# unreachable
HEXIT('ERR_INTERNAL', msg => "Unknown step specified");