PVE/API2/AccessControl.pm

   1 package PVE::API2::AccessControl;
   2
   3 use strict;
   4 use warnings;
   5
   6 use JSON;
   7 use MIME::Base64;
   8
   9 use PVE::Exception qw(raise raise_perm_exc);
  10 use PVE::SafeSyslog;
  11 use PVE::RPCEnvironment;
  12 use PVE::Cluster qw(cfs_read_file);
  13 use PVE::Corosync;
  14 use PVE::RESTHandler;
  15 use PVE::AccessControl;
  16 use PVE::JSONSchema qw(get_standard_option);
  17 use PVE::API2::Domains;
  18 use PVE::API2::User;
  19 use PVE::API2::Group;
  20 use PVE::API2::Role;
  21 use PVE::API2::ACL;
  22
  23 my $u2f_available = 0;
  24 eval {
  25     require PVE::U2F;
  26     $u2f_available = 1;
  27 };
  28
  29 use base qw(PVE::RESTHandler);
  30
  31 __PACKAGE__->register_method ({
  32     subclass => "PVE::API2::User",
  33     path => 'users',
  34 });
  35
  36 __PACKAGE__->register_method ({
  37     subclass => "PVE::API2::Group",
  38     path => 'groups',
  39 });
  40
  41 __PACKAGE__->register_method ({
  42     subclass => "PVE::API2::Role",
  43     path => 'roles',
  44 });
  45
  46 __PACKAGE__->register_method ({
  47     subclass => "PVE::API2::ACL",
  48     path => 'acl',
  49 });
  50
  51 __PACKAGE__->register_method ({
  52     subclass => "PVE::API2::Domains",
  53     path => 'domains',
  54 });
  55
  56 __PACKAGE__->register_method ({
  57     name => 'index',
  58     path => '',
  59     method => 'GET',
  60     description => "Directory index.",
  61     permissions => {
  62         user => 'all',
  63     },
  64     parameters => {
  65         additionalProperties => 0,
  66         properties => {},
  67     },
  68     returns => {
  69         type => 'array',
  70         items => {
  71             type => "object",
  72             properties => {
  73                 subdir => { type => 'string' },
  74             },
  75         },
  76         links => [ { rel => 'child', href => "{subdir}" } ],
  77     },
  78     code => sub {
  79         my ($param) = @_;
  80
  81         my $res = [];
  82
  83         my $ma = __PACKAGE__->method_attributes();
  84
  85         foreach my $info (@$ma) {
  86             next if !$info->{subclass};
  87
  88             my $subpath = $info->{match_re}->[0];
  89
  90             push @$res, { subdir => $subpath };
  91         }
  92
  93         push @$res, { subdir => 'ticket' };
  94         push @$res, { subdir => 'password' };
  95
  96         return $res;
  97     }});
  98
  99
 100 my $verify_auth = sub {
 101     my ($rpcenv, $username, $pw_or_ticket, $otp, $path, $privs) = @_;
 102
 103     my $normpath = PVE::AccessControl::normalize_path($path);
 104
 105     my $ticketuser;
 106     if (($ticketuser = PVE::AccessControl::verify_ticket($pw_or_ticket, 1)) &&
 107         ($ticketuser eq $username)) {
 108         # valid ticket
 109     } elsif (PVE::AccessControl::verify_vnc_ticket($pw_or_ticket, $username, $normpath, 1)) {
 110         # valid vnc ticket
 111     } else {
 112         $username = PVE::AccessControl::authenticate_user($username, $pw_or_ticket, $otp);
 113     }
 114
 115     my $privlist = [ PVE::Tools::split_list($privs) ];
 116     if (!($normpath && scalar(@$privlist) && $rpcenv->check($username, $normpath, $privlist))) {
 117         die "no permission ($path, $privs)\n";
 118     }
 119
 120     return { username => $username };
 121 };
 122
 123 my $create_ticket = sub {
 124     my ($rpcenv, $username, $pw_or_ticket, $otp) = @_;
 125
 126     my ($ticketuser, $u2fdata);
 127     if (($ticketuser = PVE::AccessControl::verify_ticket($pw_or_ticket, 1)) &&
 128         ($ticketuser eq 'root@pam' || $ticketuser eq $username)) {
 129         # valid ticket. Note: root@pam can create tickets for other users
 130     } else {
 131         ($username, $u2fdata) = PVE::AccessControl::authenticate_user($username, $pw_or_ticket, $otp);
 132     }
 133
 134     my %extra;
 135     my $ticket_data = $username;
 136     if (defined($u2fdata)) {
 137         my $u2f = get_u2f_instance($rpcenv, $u2fdata->@{qw(publicKey keyHandle)});
 138         my $challenge = $u2f->auth_challenge()
 139             or die "failed to get u2f challenge\n";
 140         $challenge = decode_json($challenge);
 141         $extra{U2FChallenge} = $challenge;
 142         $ticket_data = "u2f!$username!$challenge->{challenge}";
 143     }
 144
 145     my $ticket = PVE::AccessControl::assemble_ticket($ticket_data);
 146     my $csrftoken = PVE::AccessControl::assemble_csrf_prevention_token($username);
 147
 148     return {
 149         ticket => $ticket,
 150         username => $username,
 151         CSRFPreventionToken => $csrftoken,
 152         %extra,
 153     };
 154 };
 155
 156 my $compute_api_permission = sub {
 157     my ($rpcenv, $authuser) = @_;
 158
 159     my $usercfg = $rpcenv->{user_cfg};
 160
 161     my $res = {};
 162     my $priv_re_map = {
 163         vms => qr/VM\.|Permissions\.Modify/,
 164         access => qr/(User|Group)\.|Permissions\.Modify/,
 165         storage => qr/Datastore\.|Permissions\.Modify/,
 166         nodes => qr/Sys\.|Permissions\.Modify/,
 167         dc => qr/Sys\.Audit/,
 168     };
 169     map { $res->{$_} = {} } keys %$priv_re_map;
 170
 171     my $required_paths = ['/', '/nodes', '/access/groups', '/vms', '/storage'];
 172
 173     my $checked_paths = {};
 174     foreach my $path (@$required_paths, keys %{$usercfg->{acl}}) {
 175         next if $checked_paths->{$path};
 176         $checked_paths->{$path} = 1;
 177
 178         my $path_perm = $rpcenv->permissions($authuser, $path);
 179
 180         my $toplevel = ($path =~ /^\/(\w+)/) ? $1 : 'dc';
 181         if ($toplevel eq 'pool') {
 182             foreach my $priv (keys %$path_perm) {
 183                 if ($priv =~ m/^VM\./) {
 184                     $res->{vms}->{$priv} = 1;
 185                 } elsif ($priv =~ m/^Datastore\./) {
 186                     $res->{storage}->{$priv} = 1;
 187                 } elsif ($priv eq 'Permissions.Modify') {
 188                     $res->{storage}->{$priv} = 1;
 189                     $res->{vms}->{$priv} = 1;
 190                 }
 191             }
 192         } else {
 193             my $priv_regex = $priv_re_map->{$toplevel} // next;
 194             foreach my $priv (keys %$path_perm) {
 195                 next if $priv !~ m/^($priv_regex)/;
 196                 $res->{$toplevel}->{$priv} = 1;
 197             }
 198         }
 199     }
 200
 201     return $res;
 202 };
 203
 204 __PACKAGE__->register_method ({
 205     name => 'get_ticket',
 206     path => 'ticket',
 207     method => 'GET',
 208     permissions => { user => 'world' },
 209     description => "Dummy. Useful for formatters which want to provide a login page.",
 210     parameters => {
 211         additionalProperties => 0,
 212     },
 213     returns => { type => "null" },
 214     code => sub { return undef; }});
 215
 216 __PACKAGE__->register_method ({
 217     name => 'create_ticket',
 218     path => 'ticket',
 219     method => 'POST',
 220     permissions => {
 221         description => "You need to pass valid credientials.",
 222         user => 'world'
 223     },
 224     protected => 1, # else we can't access shadow files
 225     description => "Create or verify authentication ticket.",
 226     parameters => {
 227         additionalProperties => 0,
 228         properties => {
 229             username => {
 230                 description => "User name",
 231                 type => 'string',
 232                 maxLength => 64,
 233                 completion => \&PVE::AccessControl::complete_username,
 234             },
 235             realm =>  get_standard_option('realm', {
 236                 description => "You can optionally pass the realm using this parameter. Normally the realm is simply added to the username <username>\@<relam>.",
 237                 optional => 1,
 238                 completion => \&PVE::AccessControl::complete_realm,
 239             }),
 240             password => {
 241                 description => "The secret password. This can also be a valid ticket.",
 242                 type => 'string',
 243             },
 244             otp => {
 245                 description => "One-time password for Two-factor authentication.",
 246                 type => 'string',
 247                 optional => 1,
 248             },
 249             path => {
 250                 description => "Verify ticket, and check if user have access 'privs' on 'path'",
 251                 type => 'string',
 252                 requires => 'privs',
 253                 optional => 1,
 254                 maxLength => 64,
 255             },
 256             privs => {
 257                 description => "Verify ticket, and check if user have access 'privs' on 'path'",
 258                 type => 'string' , format => 'pve-priv-list',
 259                 requires => 'path',
 260                 optional => 1,
 261                 maxLength => 64,
 262             },
 263         }
 264     },
 265     returns => {
 266         type => "object",
 267         properties => {
 268             username => { type => 'string' },
 269             ticket => { type => 'string', optional => 1},
 270             CSRFPreventionToken => { type => 'string', optional => 1 },
 271             clustername => { type => 'string', optional => 1 },
 272             # cap => computed api permissions, unless there's a u2f challenge
 273         }
 274     },
 275     code => sub {
 276         my ($param) = @_;
 277
 278         my $username = $param->{username};
 279         $username .= "\@$param->{realm}" if $param->{realm};
 280
 281         my $rpcenv = PVE::RPCEnvironment::get();
 282
 283         my $res;
 284         eval {
 285             # test if user exists and is enabled
 286             $rpcenv->check_user_enabled($username);
 287
 288             if ($param->{path} && $param->{privs}) {
 289                 $res = &$verify_auth($rpcenv, $username, $param->{password}, $param->{otp},
 290                                      $param->{path}, $param->{privs});
 291             } else {
 292                 $res = &$create_ticket($rpcenv, $username, $param->{password}, $param->{otp});
 293             }
 294         };
 295         if (my $err = $@) {
 296             my $clientip = $rpcenv->get_client_ip() || '';
 297             syslog('err', "authentication failure; rhost=$clientip user=$username msg=$err");
 298             # do not return any info to prevent user enumeration attacks
 299             die PVE::Exception->new("authentication failure\n", code => 401);
 300         }
 301
 302         $res->{cap} = &$compute_api_permission($rpcenv, $username)
 303             if !defined($res->{U2FChallenge});
 304
 305         if (PVE::Corosync::check_conf_exists(1)) {
 306             if ($rpcenv->check($username, '/', ['Sys.Audit'], 1)) {
 307                 eval {
 308                     my $conf = cfs_read_file('corosync.conf');
 309                     my $totem = PVE::Corosync::totem_config($conf);
 310                     if ($totem->{cluster_name}) {
 311                         $res->{clustername} = $totem->{cluster_name};
 312                     }
 313                 };
 314                 warn "$@\n" if $@;
 315             }
 316         }
 317
 318         PVE::Cluster::log_msg('info', 'root@pam', "successful auth for user '$username'");
 319
 320         return $res;
 321     }});
 322
 323 __PACKAGE__->register_method ({
 324     name => 'change_password',
 325     path => 'password',
 326     method => 'PUT',
 327     permissions => {
 328         description => "Each user is allowed to change his own password. A user can change the password of another user if he has 'Realm.AllocateUser' (on the realm of user <userid>) and 'User.Modify' permission on /access/groups/<group> on a group where user <userid> is member of.",
 329         check => [ 'or',
 330                    ['userid-param', 'self'],
 331                    [ 'and',
 332                      [ 'userid-param', 'Realm.AllocateUser'],
 333                      [ 'userid-group', ['User.Modify']]
 334                    ]
 335             ],
 336     },
 337     protected => 1, # else we can't access shadow files
 338     description => "Change user password.",
 339     parameters => {
 340         additionalProperties => 0,
 341         properties => {
 342             userid => get_standard_option('userid-completed'),
 343             password => {
 344                 description => "The new password.",
 345                 type => 'string',
 346                 minLength => 5,
 347                 maxLength => 64,
 348             },
 349         }
 350     },
 351     returns => { type => "null" },
 352     code => sub {
 353         my ($param) = @_;
 354
 355         my $rpcenv = PVE::RPCEnvironment::get();
 356         my $authuser = $rpcenv->get_user();
 357
 358         my ($userid, $ruid, $realm) = PVE::AccessControl::verify_username($param->{userid});
 359
 360         $rpcenv->check_user_exist($userid);
 361
 362         if ($authuser eq 'root@pam') {
 363             # OK - root can change anything
 364         } else {
 365             if ($authuser eq $userid) {
 366                 $rpcenv->check_user_enabled($userid);
 367                 # OK - each user can change its own password
 368             } else {
 369                 # only root may change root password
 370                 raise_perm_exc() if $userid eq 'root@pam';
 371                 # do not allow to change system user passwords
 372                 raise_perm_exc() if $realm eq 'pam';
 373             }
 374         }
 375
 376         PVE::AccessControl::domain_set_password($realm, $ruid, $param->{password});
 377
 378         PVE::Cluster::log_msg('info', 'root@pam', "changed password for user '$userid'");
 379
 380         return undef;
 381     }});
 382
 383 sub get_u2f_config() {
 384     die "u2f support not available\n" if !$u2f_available;
 385
 386     my $dc = cfs_read_file('datacenter.cfg');
 387     my $u2f = $dc->{u2f};
 388     die "u2f not configured in datacenter.cfg\n" if !$u2f;
 389     $u2f = PVE::JSONSchema::parse_property_string($PVE::Cluster::u2f_format, $u2f);
 390     return $u2f;
 391 }
 392
 393 sub get_u2f_instance {
 394     my ($rpcenv, $publicKey, $keyHandle) = @_;
 395
 396     # We store the public key base64 encoded (as the api provides it in binary)
 397     $publicKey = decode_base64($publicKey) if defined($publicKey);
 398
 399     my $u2fconfig = get_u2f_config();
 400     my $u2f = PVE::U2F->new();
 401
 402     # via the 'Host' header (in case a node has multiple hosts available).
 403     my $origin = $u2fconfig->{origin};
 404     if (!defined($origin)) {
 405         $origin = $rpcenv->get_request_host(1);
 406         if ($origin) {
 407             $origin = "https://$origin";
 408         } else {
 409             die "failed to figure out u2f origin\n";
 410         }
 411     }
 412
 413     my $appid = $u2fconfig->{appid} // $origin;
 414     $u2f->set_appid($appid);
 415     $u2f->set_origin($origin);
 416     $u2f->set_publicKey($publicKey) if defined($publicKey);
 417     $u2f->set_keyHandle($keyHandle) if defined($keyHandle);
 418     return $u2f;
 419 }
 420
 421 __PACKAGE__->register_method ({
 422     name => 'change_tfa',
 423     path => 'tfa',
 424     method => 'PUT',
 425     permissions => {
 426         description => 'A user can change their own u2f token.',
 427         check => [ 'or',
 428                    ['userid-param', 'self'],
 429                    [ 'and',
 430                      [ 'userid-param', 'Realm.AllocateUser'],
 431                      [ 'userid-group', ['User.Modify']]
 432                    ]
 433             ],
 434     },
 435     protected => 1, # else we can't access shadow files
 436     description => "Change user u2f authentication.",
 437     parameters => {
 438         additionalProperties => 0,
 439         properties => {
 440             userid => get_standard_option('userid', {
 441                 completion => \&PVE::AccessControl::complete_username,
 442             }),
 443             password => {
 444                 optional => 1, # Only required if not root@pam
 445                 description => "The current password.",
 446                 type => 'string',
 447                 minLength => 5,
 448                 maxLength => 64,
 449             },
 450             action => {
 451                 description => 'The action to perform',
 452                 type => 'string',
 453                 enum => [qw(delete new confirm)],
 454             },
 455             response => {
 456                 optional => 1,
 457                 description => 'The response to the current registration challenge.',
 458                 type => 'string',
 459             },
 460         }
 461     },
 462     returns => { type => 'object' },
 463     code => sub {
 464         my ($param) = @_;
 465
 466         my $rpcenv = PVE::RPCEnvironment::get();
 467         my $authuser = $rpcenv->get_user();
 468
 469         my $action = delete $param->{action};
 470         my $response = delete $param->{response};
 471         my $password = delete($param->{password}) // '';
 472
 473         my ($userid, $ruid, $realm) = PVE::AccessControl::verify_username($param->{userid});
 474         $rpcenv->check_user_exist($userid);
 475
 476         # Only root may modify root
 477         raise_perm_exc() if $userid eq 'root@pam' && $authuser ne 'root@pam';
 478
 479         # Regular users need to confirm their password to change u2f settings.
 480         if ($authuser ne 'root@pam') {
 481             raise_param_exc('password' => 'password is required to modify u2f data')
 482                 if !defined($password);
 483             my $domain_cfg = cfs_read_file('domains.cfg');
 484             my $cfg = $domain_cfg->{ids}->{$realm};
 485             die "auth domain '$realm' does not exists\n" if !$cfg;
 486             my $plugin = PVE::Auth::Plugin->lookup($cfg->{type});
 487             $plugin->authenticate_user($cfg, $realm, $ruid, $password);
 488         }
 489
 490         if ($action eq 'delete') {
 491             PVE::AccessControl::user_set_tfa($userid, $realm, undef, undef);
 492             PVE::Cluster::log_msg('info', $authuser, "deleted u2f data for user '$userid'");
 493         } elsif ($action eq 'new') {
 494             my $u2f = get_u2f_instance($rpcenv);
 495             my $challenge = $u2f->registration_challenge()
 496                 or raise("failed to get u2f challenge");
 497             $challenge = decode_json($challenge);
 498             PVE::AccessControl::user_set_tfa($userid, $realm, 'u2f', $challenge);
 499             return $challenge;
 500         } elsif ($action eq 'confirm') {
 501             raise_param_exc('response' => "confirm action requires the 'response' parameter to be set")
 502                 if !defined($response);
 503
 504             my ($type, $u2fdata) = PVE::AccessControl::user_get_tfa($userid, $realm);
 505             raise("no u2f data available")
 506                 if (!defined($type) || $type ne 'u2f');
 507
 508             my $challenge = $u2fdata->{challenge}
 509                 or raise("no active challenge");
 510
 511             my $u2f = get_u2f_instance($rpcenv);
 512             $u2f->set_challenge($challenge);
 513             my ($keyHandle, $publicKey) = $u2f->registration_verify($response);
 514             PVE::AccessControl::user_set_tfa($userid, $realm, 'u2f', {
 515                 keyHandle => $keyHandle,
 516                 publicKey => encode_base64($publicKey, ''),
 517             });
 518         } else {
 519             die "invalid action: $action\n";
 520         }
 521
 522         return {};
 523     }});
 524
 525 __PACKAGE__->register_method({
 526     name => 'verify_tfa',
 527     path => 'tfa',
 528     method => 'POST',
 529     permissions => { user => 'all' },
 530     protected => 1, # else we can't access shadow files
 531     description => 'Finish a u2f challenge.',
 532     parameters => {
 533         additionalProperties => 0,
 534         properties => {
 535             response => {
 536                 type => 'string',
 537                 description => 'The response to the current authentication challenge.',
 538             },
 539         }
 540     },
 541     returns => {
 542         type => 'object',
 543         properties => {
 544             ticket => { type => 'string' },
 545             # cap
 546         }
 547     },
 548     code => sub {
 549         my ($param) = @_;
 550
 551         my $rpcenv = PVE::RPCEnvironment::get();
 552         my $challenge = $rpcenv->get_u2f_challenge()
 553            or raise('no active challenge');
 554         my $authuser = $rpcenv->get_user();
 555         my ($username, undef, $realm) = PVE::AccessControl::verify_username($authuser);
 556
 557         my ($tfa_type, $u2fdata) = PVE::AccessControl::user_get_tfa($username, $realm);
 558         if (!defined($tfa_type) || $tfa_type ne 'u2f') {
 559             raise('no u2f data available');
 560         }
 561
 562         my $keyHandle = $u2fdata->{keyHandle};
 563         my $publicKey = $u2fdata->{publicKey};
 564         raise("incomplete u2f setup")
 565             if !defined($keyHandle) || !defined($publicKey);
 566
 567         my $u2f = get_u2f_instance($rpcenv, $publicKey, $keyHandle);
 568         $u2f->set_challenge($challenge);
 569
 570         eval {
 571             my ($counter, $present) = $u2f->auth_verify($param->{response});
 572             # Do we want to do anything with these?
 573         };
 574         if (my $err = $@) {
 575             my $clientip = $rpcenv->get_client_ip() || '';
 576             syslog('err', "authentication verification failure; rhost=$clientip user=$authuser msg=$err");
 577             die PVE::Exception->new("authentication failure\n", code => 401);
 578         }
 579
 580         # create a new ticket for the user:
 581         my $ticket_data = "u2f!$authuser!verified";
 582         return {
 583             ticket => PVE::AccessControl::assemble_ticket($ticket_data),
 584             cap => &$compute_api_permission($rpcenv, $authuser),
 585         }
 586     }});
 587
 588 1;