pve-access-control/PVE/API2/AccessControl.pm
Wolfgang Bumiller 18f8ba1803 u2f authentication
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
2019-04-03 08:04:00 +02:00

589 lines
16 KiB
Perl

package PVE::API2::AccessControl;
use strict;
use warnings;
use JSON;
use MIME::Base64;
use PVE::Exception qw(raise raise_perm_exc);
use PVE::SafeSyslog;
use PVE::RPCEnvironment;
use PVE::Cluster qw(cfs_read_file);
use PVE::Corosync;
use PVE::RESTHandler;
use PVE::AccessControl;
use PVE::JSONSchema qw(get_standard_option);
use PVE::API2::Domains;
use PVE::API2::User;
use PVE::API2::Group;
use PVE::API2::Role;
use PVE::API2::ACL;
my $u2f_available = 0;
eval {
require PVE::U2F;
$u2f_available = 1;
};
use base qw(PVE::RESTHandler);
__PACKAGE__->register_method ({
subclass => "PVE::API2::User",
path => 'users',
});
__PACKAGE__->register_method ({
subclass => "PVE::API2::Group",
path => 'groups',
});
__PACKAGE__->register_method ({
subclass => "PVE::API2::Role",
path => 'roles',
});
__PACKAGE__->register_method ({
subclass => "PVE::API2::ACL",
path => 'acl',
});
__PACKAGE__->register_method ({
subclass => "PVE::API2::Domains",
path => 'domains',
});
__PACKAGE__->register_method ({
name => 'index',
path => '',
method => 'GET',
description => "Directory index.",
permissions => {
user => 'all',
},
parameters => {
additionalProperties => 0,
properties => {},
},
returns => {
type => 'array',
items => {
type => "object",
properties => {
subdir => { type => 'string' },
},
},
links => [ { rel => 'child', href => "{subdir}" } ],
},
code => sub {
my ($param) = @_;
my $res = [];
my $ma = __PACKAGE__->method_attributes();
foreach my $info (@$ma) {
next if !$info->{subclass};
my $subpath = $info->{match_re}->[0];
push @$res, { subdir => $subpath };
}
push @$res, { subdir => 'ticket' };
push @$res, { subdir => 'password' };
return $res;
}});
my $verify_auth = sub {
my ($rpcenv, $username, $pw_or_ticket, $otp, $path, $privs) = @_;
my $normpath = PVE::AccessControl::normalize_path($path);
my $ticketuser;
if (($ticketuser = PVE::AccessControl::verify_ticket($pw_or_ticket, 1)) &&
($ticketuser eq $username)) {
# valid ticket
} elsif (PVE::AccessControl::verify_vnc_ticket($pw_or_ticket, $username, $normpath, 1)) {
# valid vnc ticket
} else {
$username = PVE::AccessControl::authenticate_user($username, $pw_or_ticket, $otp);
}
my $privlist = [ PVE::Tools::split_list($privs) ];
if (!($normpath && scalar(@$privlist) && $rpcenv->check($username, $normpath, $privlist))) {
die "no permission ($path, $privs)\n";
}
return { username => $username };
};
my $create_ticket = sub {
my ($rpcenv, $username, $pw_or_ticket, $otp) = @_;
my ($ticketuser, $u2fdata);
if (($ticketuser = PVE::AccessControl::verify_ticket($pw_or_ticket, 1)) &&
($ticketuser eq 'root@pam' || $ticketuser eq $username)) {
# valid ticket. Note: root@pam can create tickets for other users
} else {
($username, $u2fdata) = PVE::AccessControl::authenticate_user($username, $pw_or_ticket, $otp);
}
my %extra;
my $ticket_data = $username;
if (defined($u2fdata)) {
my $u2f = get_u2f_instance($rpcenv, $u2fdata->@{qw(publicKey keyHandle)});
my $challenge = $u2f->auth_challenge()
or die "failed to get u2f challenge\n";
$challenge = decode_json($challenge);
$extra{U2FChallenge} = $challenge;
$ticket_data = "u2f!$username!$challenge->{challenge}";
}
my $ticket = PVE::AccessControl::assemble_ticket($ticket_data);
my $csrftoken = PVE::AccessControl::assemble_csrf_prevention_token($username);
return {
ticket => $ticket,
username => $username,
CSRFPreventionToken => $csrftoken,
%extra,
};
};
my $compute_api_permission = sub {
my ($rpcenv, $authuser) = @_;
my $usercfg = $rpcenv->{user_cfg};
my $res = {};
my $priv_re_map = {
vms => qr/VM\.|Permissions\.Modify/,
access => qr/(User|Group)\.|Permissions\.Modify/,
storage => qr/Datastore\.|Permissions\.Modify/,
nodes => qr/Sys\.|Permissions\.Modify/,
dc => qr/Sys\.Audit/,
};
map { $res->{$_} = {} } keys %$priv_re_map;
my $required_paths = ['/', '/nodes', '/access/groups', '/vms', '/storage'];
my $checked_paths = {};
foreach my $path (@$required_paths, keys %{$usercfg->{acl}}) {
next if $checked_paths->{$path};
$checked_paths->{$path} = 1;
my $path_perm = $rpcenv->permissions($authuser, $path);
my $toplevel = ($path =~ /^\/(\w+)/) ? $1 : 'dc';
if ($toplevel eq 'pool') {
foreach my $priv (keys %$path_perm) {
if ($priv =~ m/^VM\./) {
$res->{vms}->{$priv} = 1;
} elsif ($priv =~ m/^Datastore\./) {
$res->{storage}->{$priv} = 1;
} elsif ($priv eq 'Permissions.Modify') {
$res->{storage}->{$priv} = 1;
$res->{vms}->{$priv} = 1;
}
}
} else {
my $priv_regex = $priv_re_map->{$toplevel} // next;
foreach my $priv (keys %$path_perm) {
next if $priv !~ m/^($priv_regex)/;
$res->{$toplevel}->{$priv} = 1;
}
}
}
return $res;
};
__PACKAGE__->register_method ({
name => 'get_ticket',
path => 'ticket',
method => 'GET',
permissions => { user => 'world' },
description => "Dummy. Useful for formatters which want to provide a login page.",
parameters => {
additionalProperties => 0,
},
returns => { type => "null" },
code => sub { return undef; }});
__PACKAGE__->register_method ({
name => 'create_ticket',
path => 'ticket',
method => 'POST',
permissions => {
description => "You need to pass valid credientials.",
user => 'world'
},
protected => 1, # else we can't access shadow files
description => "Create or verify authentication ticket.",
parameters => {
additionalProperties => 0,
properties => {
username => {
description => "User name",
type => 'string',
maxLength => 64,
completion => \&PVE::AccessControl::complete_username,
},
realm => get_standard_option('realm', {
description => "You can optionally pass the realm using this parameter. Normally the realm is simply added to the username <username>\@<relam>.",
optional => 1,
completion => \&PVE::AccessControl::complete_realm,
}),
password => {
description => "The secret password. This can also be a valid ticket.",
type => 'string',
},
otp => {
description => "One-time password for Two-factor authentication.",
type => 'string',
optional => 1,
},
path => {
description => "Verify ticket, and check if user have access 'privs' on 'path'",
type => 'string',
requires => 'privs',
optional => 1,
maxLength => 64,
},
privs => {
description => "Verify ticket, and check if user have access 'privs' on 'path'",
type => 'string' , format => 'pve-priv-list',
requires => 'path',
optional => 1,
maxLength => 64,
},
}
},
returns => {
type => "object",
properties => {
username => { type => 'string' },
ticket => { type => 'string', optional => 1},
CSRFPreventionToken => { type => 'string', optional => 1 },
clustername => { type => 'string', optional => 1 },
# cap => computed api permissions, unless there's a u2f challenge
}
},
code => sub {
my ($param) = @_;
my $username = $param->{username};
$username .= "\@$param->{realm}" if $param->{realm};
my $rpcenv = PVE::RPCEnvironment::get();
my $res;
eval {
# test if user exists and is enabled
$rpcenv->check_user_enabled($username);
if ($param->{path} && $param->{privs}) {
$res = &$verify_auth($rpcenv, $username, $param->{password}, $param->{otp},
$param->{path}, $param->{privs});
} else {
$res = &$create_ticket($rpcenv, $username, $param->{password}, $param->{otp});
}
};
if (my $err = $@) {
my $clientip = $rpcenv->get_client_ip() || '';
syslog('err', "authentication failure; rhost=$clientip user=$username msg=$err");
# do not return any info to prevent user enumeration attacks
die PVE::Exception->new("authentication failure\n", code => 401);
}
$res->{cap} = &$compute_api_permission($rpcenv, $username)
if !defined($res->{U2FChallenge});
if (PVE::Corosync::check_conf_exists(1)) {
if ($rpcenv->check($username, '/', ['Sys.Audit'], 1)) {
eval {
my $conf = cfs_read_file('corosync.conf');
my $totem = PVE::Corosync::totem_config($conf);
if ($totem->{cluster_name}) {
$res->{clustername} = $totem->{cluster_name};
}
};
warn "$@\n" if $@;
}
}
PVE::Cluster::log_msg('info', 'root@pam', "successful auth for user '$username'");
return $res;
}});
__PACKAGE__->register_method ({
name => 'change_password',
path => 'password',
method => 'PUT',
permissions => {
description => "Each user is allowed to change his own password. A user can change the password of another user if he has 'Realm.AllocateUser' (on the realm of user <userid>) and 'User.Modify' permission on /access/groups/<group> on a group where user <userid> is member of.",
check => [ 'or',
['userid-param', 'self'],
[ 'and',
[ 'userid-param', 'Realm.AllocateUser'],
[ 'userid-group', ['User.Modify']]
]
],
},
protected => 1, # else we can't access shadow files
description => "Change user password.",
parameters => {
additionalProperties => 0,
properties => {
userid => get_standard_option('userid-completed'),
password => {
description => "The new password.",
type => 'string',
minLength => 5,
maxLength => 64,
},
}
},
returns => { type => "null" },
code => sub {
my ($param) = @_;
my $rpcenv = PVE::RPCEnvironment::get();
my $authuser = $rpcenv->get_user();
my ($userid, $ruid, $realm) = PVE::AccessControl::verify_username($param->{userid});
$rpcenv->check_user_exist($userid);
if ($authuser eq 'root@pam') {
# OK - root can change anything
} else {
if ($authuser eq $userid) {
$rpcenv->check_user_enabled($userid);
# OK - each user can change its own password
} else {
# only root may change root password
raise_perm_exc() if $userid eq 'root@pam';
# do not allow to change system user passwords
raise_perm_exc() if $realm eq 'pam';
}
}
PVE::AccessControl::domain_set_password($realm, $ruid, $param->{password});
PVE::Cluster::log_msg('info', 'root@pam', "changed password for user '$userid'");
return undef;
}});
sub get_u2f_config() {
die "u2f support not available\n" if !$u2f_available;
my $dc = cfs_read_file('datacenter.cfg');
my $u2f = $dc->{u2f};
die "u2f not configured in datacenter.cfg\n" if !$u2f;
$u2f = PVE::JSONSchema::parse_property_string($PVE::Cluster::u2f_format, $u2f);
return $u2f;
}
sub get_u2f_instance {
my ($rpcenv, $publicKey, $keyHandle) = @_;
# We store the public key base64 encoded (as the api provides it in binary)
$publicKey = decode_base64($publicKey) if defined($publicKey);
my $u2fconfig = get_u2f_config();
my $u2f = PVE::U2F->new();
# via the 'Host' header (in case a node has multiple hosts available).
my $origin = $u2fconfig->{origin};
if (!defined($origin)) {
$origin = $rpcenv->get_request_host(1);
if ($origin) {
$origin = "https://$origin";
} else {
die "failed to figure out u2f origin\n";
}
}
my $appid = $u2fconfig->{appid} // $origin;
$u2f->set_appid($appid);
$u2f->set_origin($origin);
$u2f->set_publicKey($publicKey) if defined($publicKey);
$u2f->set_keyHandle($keyHandle) if defined($keyHandle);
return $u2f;
}
__PACKAGE__->register_method ({
name => 'change_tfa',
path => 'tfa',
method => 'PUT',
permissions => {
description => 'A user can change their own u2f token.',
check => [ 'or',
['userid-param', 'self'],
[ 'and',
[ 'userid-param', 'Realm.AllocateUser'],
[ 'userid-group', ['User.Modify']]
]
],
},
protected => 1, # else we can't access shadow files
description => "Change user u2f authentication.",
parameters => {
additionalProperties => 0,
properties => {
userid => get_standard_option('userid', {
completion => \&PVE::AccessControl::complete_username,
}),
password => {
optional => 1, # Only required if not root@pam
description => "The current password.",
type => 'string',
minLength => 5,
maxLength => 64,
},
action => {
description => 'The action to perform',
type => 'string',
enum => [qw(delete new confirm)],
},
response => {
optional => 1,
description => 'The response to the current registration challenge.',
type => 'string',
},
}
},
returns => { type => 'object' },
code => sub {
my ($param) = @_;
my $rpcenv = PVE::RPCEnvironment::get();
my $authuser = $rpcenv->get_user();
my $action = delete $param->{action};
my $response = delete $param->{response};
my $password = delete($param->{password}) // '';
my ($userid, $ruid, $realm) = PVE::AccessControl::verify_username($param->{userid});
$rpcenv->check_user_exist($userid);
# Only root may modify root
raise_perm_exc() if $userid eq 'root@pam' && $authuser ne 'root@pam';
# Regular users need to confirm their password to change u2f settings.
if ($authuser ne 'root@pam') {
raise_param_exc('password' => 'password is required to modify u2f data')
if !defined($password);
my $domain_cfg = cfs_read_file('domains.cfg');
my $cfg = $domain_cfg->{ids}->{$realm};
die "auth domain '$realm' does not exists\n" if !$cfg;
my $plugin = PVE::Auth::Plugin->lookup($cfg->{type});
$plugin->authenticate_user($cfg, $realm, $ruid, $password);
}
if ($action eq 'delete') {
PVE::AccessControl::user_set_tfa($userid, $realm, undef, undef);
PVE::Cluster::log_msg('info', $authuser, "deleted u2f data for user '$userid'");
} elsif ($action eq 'new') {
my $u2f = get_u2f_instance($rpcenv);
my $challenge = $u2f->registration_challenge()
or raise("failed to get u2f challenge");
$challenge = decode_json($challenge);
PVE::AccessControl::user_set_tfa($userid, $realm, 'u2f', $challenge);
return $challenge;
} elsif ($action eq 'confirm') {
raise_param_exc('response' => "confirm action requires the 'response' parameter to be set")
if !defined($response);
my ($type, $u2fdata) = PVE::AccessControl::user_get_tfa($userid, $realm);
raise("no u2f data available")
if (!defined($type) || $type ne 'u2f');
my $challenge = $u2fdata->{challenge}
or raise("no active challenge");
my $u2f = get_u2f_instance($rpcenv);
$u2f->set_challenge($challenge);
my ($keyHandle, $publicKey) = $u2f->registration_verify($response);
PVE::AccessControl::user_set_tfa($userid, $realm, 'u2f', {
keyHandle => $keyHandle,
publicKey => encode_base64($publicKey, ''),
});
} else {
die "invalid action: $action\n";
}
return {};
}});
__PACKAGE__->register_method({
name => 'verify_tfa',
path => 'tfa',
method => 'POST',
permissions => { user => 'all' },
protected => 1, # else we can't access shadow files
description => 'Finish a u2f challenge.',
parameters => {
additionalProperties => 0,
properties => {
response => {
type => 'string',
description => 'The response to the current authentication challenge.',
},
}
},
returns => {
type => 'object',
properties => {
ticket => { type => 'string' },
# cap
}
},
code => sub {
my ($param) = @_;
my $rpcenv = PVE::RPCEnvironment::get();
my $challenge = $rpcenv->get_u2f_challenge()
or raise('no active challenge');
my $authuser = $rpcenv->get_user();
my ($username, undef, $realm) = PVE::AccessControl::verify_username($authuser);
my ($tfa_type, $u2fdata) = PVE::AccessControl::user_get_tfa($username, $realm);
if (!defined($tfa_type) || $tfa_type ne 'u2f') {
raise('no u2f data available');
}
my $keyHandle = $u2fdata->{keyHandle};
my $publicKey = $u2fdata->{publicKey};
raise("incomplete u2f setup")
if !defined($keyHandle) || !defined($publicKey);
my $u2f = get_u2f_instance($rpcenv, $publicKey, $keyHandle);
$u2f->set_challenge($challenge);
eval {
my ($counter, $present) = $u2f->auth_verify($param->{response});
# Do we want to do anything with these?
};
if (my $err = $@) {
my $clientip = $rpcenv->get_client_ip() || '';
syslog('err', "authentication verification failure; rhost=$clientip user=$authuser msg=$err");
die PVE::Exception->new("authentication failure\n", code => 401);
}
# create a new ticket for the user:
my $ticket_data = "u2f!$authuser!verified";
return {
ticket => PVE::AccessControl::assemble_ticket($ticket_data),
cap => &$compute_api_permission($rpcenv, $authuser),
}
}});
1;