/mandos/release : revision 237.7.486

9

* "browse_callback", and parts of "main".

10

*

11

* Everything else is

12

13

14

*

15

* This program is free software: you can redistribute it and/or

16

* modify it under the terms of the GNU General Public License as

17

* published by the Free Software Foundation, either version 3 of the

18

* License, or (at your option) any later version.

19

*

20

* This program is distributed in the hope that it will be useful, but

12

13

14

*

15

* This file is part of Mandos.

16

*

17

* Mandos is free software: you can redistribute it and/or modify it

18

* under the terms of the GNU General Public License as published by

19

* the Free Software Foundation, either version 3 of the License, or

20

* (at your option) any later version.

21

*

22

* Mandos is distributed in the hope that it will be useful, but

21

23

* WITHOUT ANY WARRANTY; without even the implied warranty of

22

24

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

23

25

* General Public License for more details.

24

26

*

25

27

* You should have received a copy of the GNU General Public License

26

* along with this program. If not, see

27

* <http://www.gnu.org/licenses/>.

28

* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

28

29

*

29

30

* Contact the authors at <mandos@recompile.se>.

30

31

*/

46

47

#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),

47

48

strtof(), abort() */

48

49

#include <stdbool.h> /* bool, false, true */

49

#include <string.h> /* memset(), strcmp(), strlen(),

50

strerror(), asprintf(), strcpy() */

50

#include <string.h> /* strcmp(), strlen(), strerror(),

51

asprintf(), strncpy(), strsignal()

52

*/

51

53

#include <sys/ioctl.h> /* ioctl */

52

54

#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

53

55

sockaddr_in6, PF_INET6,

57

59

#include <sys/socket.h> /* socket(), struct sockaddr_in6,

58

60

inet_pton(), connect(),

59

61

getnameinfo() */

60

#include <fcntl.h> /* open(), unlinkat() */

62

#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */

61

63

#include <dirent.h> /* opendir(), struct dirent, readdir()

62

64

*/

63

65

#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,

64

66

strtoimax() */

65

#include <errno.h> /* perror(), errno,

67

#include <errno.h> /* perror(), errno, EINTR, EINVAL,

68

EAI_SYSTEM, ENETUNREACH,

69

EHOSTUNREACH, ECONNREFUSED, EPROTO,

70

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

71

ENOTEMPTY,

66

72

program_invocation_short_name */

67

73

#include <time.h> /* nanosleep(), time(), sleep() */

68

74

#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,

305

311

return false;

306

312

}

307

313

308

ret = (int)TEMP_FAILURE_RETRY(close(fd));

314

ret = close(fd);

309

315

if(ret == -1){

310

316

perror_plus("close");

311

317

}

493

499

return plaintext_length;

494

500

}

495

501

502

__attribute__((warn_unused_result, const))

503

static const char *safe_string(const char *str){

504

if(str == NULL)

505

return "(unknown)";

506

return str;

507

}

508

496

509

__attribute__((warn_unused_result))

497

510

static const char *safer_gnutls_strerror(int value){

498

511

const char *ret = gnutls_strerror(value);

499

if(ret == NULL)

500

ret = "(unknown)";

501

return ret;

512

return safe_string(ret);

502

513

}

503

514

504

515

/* GnuTLS log function callback */

508

519

fprintf_plus(stderr, "GnuTLS: %s", string);

509

520

}

510

521

511

__attribute__((nonnull, warn_unused_result))

522

__attribute__((nonnull(1, 2, 4), warn_unused_result))

512

523

static int init_gnutls_global(const char *pubkeyfilename,

513

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

514

526

mandos_context *mc){

515

527

int ret;

528

unsigned int uret;

516

529

517

530

if(debug){

518

531

fprintf_plus(stderr, "Initializing GnuTLS\n");

519

532

}

520

533

521

ret = gnutls_global_init();

522

if(ret != GNUTLS_E_SUCCESS){

523

fprintf_plus(stderr, "GnuTLS global_init: %s\n",

524

safer_gnutls_strerror(ret));

525

return -1;

526

}

527

528

534

if(debug){

529

535

/* "Use a log level over 10 to enable all debugging options."

530

536

* - GnuTLS manual

538

544

if(ret != GNUTLS_E_SUCCESS){

539

545

fprintf_plus(stderr, "GnuTLS memory error: %s\n",

540

546

safer_gnutls_strerror(ret));

541

gnutls_global_deinit();

542

547

return -1;

543

548

}

544

549

569

574

safer_gnutls_strerror(ret));

570

575

goto globalfail;

571

576

}

572

ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);

573

if(ret != GNUTLS_E_SUCCESS){

574

fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",

575

safer_gnutls_strerror(ret));

576

goto globalfail;

577

}

578

577

/* If a Diffie-Hellman parameters file was given, try to use it */

578

if(dhparamsfilename != NULL){

579

gnutls_datum_t params = { .data = NULL, .size = 0 };

580

do {

581

int dhpfile = open(dhparamsfilename, O_RDONLY);

582

if(dhpfile == -1){

583

perror_plus("open");

584

dhparamsfilename = NULL;

585

break;

586

}

587

size_t params_capacity = 0;

588

while(true){

589

params_capacity = incbuffer((char **)&params.data,

590

(size_t)params.size,

591

(size_t)params_capacity);

592

if(params_capacity == 0){

593

perror_plus("incbuffer");

594

free(params.data);

595

params.data = NULL;

596

dhparamsfilename = NULL;

597

break;

598

}

599

ssize_t bytes_read = read(dhpfile,

600

params.data + params.size,

601

BUFFER_SIZE);

602

/* EOF */

603

if(bytes_read == 0){

604

break;

605

}

606

/* check bytes_read for failure */

607

if(bytes_read < 0){

608

perror_plus("read");

609

free(params.data);

610

params.data = NULL;

611

dhparamsfilename = NULL;

612

break;

613

}

614

params.size += (unsigned int)bytes_read;

615

}

616

if(params.data == NULL){

617

dhparamsfilename = NULL;

618

}

619

if(dhparamsfilename == NULL){

620

break;

621

}

622

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

623

GNUTLS_X509_FMT_PEM);

624

if(ret != GNUTLS_E_SUCCESS){

625

fprintf_plus(stderr, "Failed to parse DH parameters in file"

626

" \"%s\": %s\n", dhparamsfilename,

627

safer_gnutls_strerror(ret));

628

dhparamsfilename = NULL;

629

}

630

free(params.data);

631

} while(false);

632

}

633

if(dhparamsfilename == NULL){

634

if(mc->dh_bits == 0){

635

/* Find out the optimal number of DH bits */

636

/* Try to read the private key file */

637

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

638

do {

639

int secfile = open(seckeyfilename, O_RDONLY);

640

if(secfile == -1){

641

perror_plus("open");

642

break;

643

}

644

size_t buffer_capacity = 0;

645

while(true){

646

buffer_capacity = incbuffer((char **)&buffer.data,

647

(size_t)buffer.size,

648

(size_t)buffer_capacity);

649

if(buffer_capacity == 0){

650

perror_plus("incbuffer");

651

free(buffer.data);

652

buffer.data = NULL;

653

break;

654

}

655

ssize_t bytes_read = read(secfile,

656

buffer.data + buffer.size,

657

BUFFER_SIZE);

658

/* EOF */

659

if(bytes_read == 0){

660

break;

661

}

662

/* check bytes_read for failure */

663

if(bytes_read < 0){

664

perror_plus("read");

665

free(buffer.data);

666

buffer.data = NULL;

667

break;

668

}

669

buffer.size += (unsigned int)bytes_read;

670

}

671

close(secfile);

672

} while(false);

673

/* If successful, use buffer to parse private key */

674

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

675

if(buffer.data != NULL){

676

{

677

gnutls_openpgp_privkey_t privkey = NULL;

678

ret = gnutls_openpgp_privkey_init(&privkey);

679

if(ret != GNUTLS_E_SUCCESS){

680

fprintf_plus(stderr, "Error initializing OpenPGP key"

681

" structure: %s",

682

safer_gnutls_strerror(ret));

683

free(buffer.data);

684

buffer.data = NULL;

685

} else {

686

ret = gnutls_openpgp_privkey_import

687

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

688

if(ret != GNUTLS_E_SUCCESS){

689

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

690

safer_gnutls_strerror(ret));

691

privkey = NULL;

692

}

693

free(buffer.data);

694

buffer.data = NULL;

695

if(privkey != NULL){

696

/* Use private key to suggest an appropriate

697

sec_param */

698

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

699

gnutls_openpgp_privkey_deinit(privkey);

700

if(debug){

701

fprintf_plus(stderr, "This OpenPGP key implies using"

702

" a GnuTLS security parameter \"%s\".\n",

703

safe_string(gnutls_sec_param_get_name

704

(sec_param)));

705

}

706

}

707

}

708

}

709

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

710

/* Err on the side of caution */

711

sec_param = GNUTLS_SEC_PARAM_ULTRA;

712

if(debug){

713

fprintf_plus(stderr, "Falling back to security parameter"

714

" \"%s\"\n",

715

safe_string(gnutls_sec_param_get_name

716

(sec_param)));

717

}

718

}

719

}

720

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

721

if(uret != 0){

722

mc->dh_bits = uret;

723

if(debug){

724

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

725

" implies %u DH bits; using that.\n",

726

safe_string(gnutls_sec_param_get_name

727

(sec_param)),

728

mc->dh_bits);

729

}

730

} else {

731

fprintf_plus(stderr, "Failed to get implied number of DH"

732

" bits for security parameter \"%s\"): %s\n",

733

safe_string(gnutls_sec_param_get_name

734

(sec_param)),

735

safer_gnutls_strerror(ret));

736

goto globalfail;

737

}

738

} else if(debug){

739

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

740

mc->dh_bits);

741

}

742

ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);

743

if(ret != GNUTLS_E_SUCCESS){

744

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"

745

" bits): %s\n", mc->dh_bits,

746

safer_gnutls_strerror(ret));

747

goto globalfail;

748

}

749

}

579

750

gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);

580

751

581

752

return 0;

583

754

globalfail:

584

755

585

756

gnutls_certificate_free_credentials(mc->cred);

586

gnutls_global_deinit();

587

757

gnutls_dh_params_deinit(mc->dh_params);

588

758

return -1;

589

759

}

641

811

/* ignore client certificate if any. */

642

812

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

813

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

645

646

814

return 0;

647

815

}

648

816

652

820

653

821

/* Set effective uid to 0, return errno */

654

822

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

823

int raise_privileges(void){

824

int old_errno = errno;

825

int ret = 0;

658

826

if(seteuid(0) == -1){

659

ret_errno = errno;

827

ret = errno;

660

828

}

661

829

errno = old_errno;

662

return ret_errno;

830

return ret;

663

831

}

664

832

665

833

/* Set effective and real user ID to 0. Return errno. */

666

834

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

835

int raise_privileges_permanently(void){

836

int old_errno = errno;

837

int ret = raise_privileges();

838

if(ret != 0){

671

839

errno = old_errno;

672

return ret_errno;

840

return ret;

673

841

}

674

842

if(setuid(0) == -1){

675

ret_errno = errno;

843

ret = errno;

676

844

}

677

845

errno = old_errno;

678

return ret_errno;

846

return ret;

679

847

}

680

848

681

849

/* Set effective user ID to unprivileged saved user ID */

682

850

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

851

int lower_privileges(void){

852

int old_errno = errno;

853

int ret = 0;

686

854

if(seteuid(uid) == -1){

687

ret_errno = errno;

855

ret = errno;

688

856

}

689

857

errno = old_errno;

690

return ret_errno;

858

return ret;

691

859

}

692

860

693

861

/* Lower privileges permanently */

694

862

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

863

int lower_privileges_permanently(void){

864

int old_errno = errno;

865

int ret = 0;

698

866

if(setuid(uid) == -1){

699

ret_errno = errno;

867

ret = errno;

700

868

}

701

869

errno = old_errno;

702

return ret_errno;

870

return ret;

703

871

}

704

872

705

/* Helper function to add_local_route() and remove_local_route() */

873

/* Helper function to add_local_route() and delete_local_route() */

706

874

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

875

static bool add_delete_local_route(const bool add,

708

876

const char *address,

709

877

AvahiIfIndex if_index){

710

878

int ret;

711

879

char helper[] = "mandos-client-iprouteadddel";

712

880

char add_arg[] = "add";

713

881

char delete_arg[] = "delete";

882

char debug_flag[] = "--debug";

714

883

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

884

if(pluginhelperdir == NULL){

716

885

if(debug){

760

929

perror_plus("dup2(devnull, STDIN_FILENO)");

761

930

_exit(EX_OSERR);

762

931

}

763

ret = (int)TEMP_FAILURE_RETRY(close(devnull));

932

ret = close(devnull);

764

933

if(ret == -1){

765

934

perror_plus("close");

766

935

_exit(EX_OSERR);

783

952

helper, O_RDONLY));

784

953

if(helper_fd == -1){

785

954

perror_plus("openat");

955

close(helperdir_fd);

786

956

_exit(EX_UNAVAILABLE);

787

957

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

958

close(helperdir_fd);

789

959

#ifdef __GNUC__

790

960

#pragma GCC diagnostic push

791

961

#pragma GCC diagnostic ignored "-Wcast-qual"

792

962

#endif

793

963

if(fexecve(helper_fd, (char *const [])

794

964

{ helper, add ? add_arg : delete_arg, (char *)address,

795

interface, NULL }, environ) == -1){

965

interface, debug ? debug_flag : NULL, NULL },

966

environ) == -1){

796

967

#ifdef __GNUC__

797

968

#pragma GCC diagnostic pop

798

969

#endif

850

1021

__attribute__((nonnull, warn_unused_result))

851

1022

static bool add_local_route(const char *address,

852

1023

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

1024

if(debug){

1025

fprintf_plus(stderr, "Adding route to %s\n", address);

1026

}

1027

return add_delete_local_route(true, address, if_index);

854

1028

}

855

1029

856

1030

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

1031

static bool delete_local_route(const char *address,

858

1032

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

1033

if(debug){

1034

fprintf_plus(stderr, "Removing route to %s\n", address);

1035

}

1036

return add_delete_local_route(false, address, if_index);

860

1037

}

861

1038

862

1039

/* Called when a Mandos server is found */

903

1080

bool match = false;

904

1081

{

905

1082

char *interface = NULL;

906

while((interface=argz_next(mc->interfaces, mc->interfaces_size,

907

interface))){

1083

while((interface = argz_next(mc->interfaces,

1084

mc->interfaces_size,

1085

interface))){

908

1086

if(if_nametoindex(interface) == (unsigned int)if_index){

909

1087

match = true;

910

1088

break;

952

1130

goto mandos_end;

953

1131

}

954

1132

955

memset(&to, 0, sizeof(to));

956

1133

if(af == AF_INET6){

957

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

958

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

1134

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1135

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1136

ret = inet_pton(af, ip, &to6->sin6_addr);

959

1137

} else { /* IPv4 */

960

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

961

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

1138

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1139

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1140

ret = inet_pton(af, ip, &to4->sin_addr);

962

1141

}

963

1142

if(ret < 0 ){

964

1143

int e = errno;

1043

1222

sizeof(struct sockaddr_in));

1044

1223

}

1045

1224

if(ret < 0){

1046

if(errno == ENETUNREACH

1225

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1047

1226

and if_index != AVAHI_IF_UNSPEC

1048

1227

and connect_to == NULL

1049

1228

and not route_added and

1062

1241

with an explicit route added with the server's address.

1063

1242

1064

1243

Avahi bug reference:

1065

http://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1244

https://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1066

1245

https://bugs.debian.org/587961

1067

1246

*/

1247

if(debug){

1248

fprintf_plus(stderr, "Mandos server unreachable, trying"

1249

" direct route\n");

1250

}

1068

1251

int e = errno;

1069

1252

route_added = add_local_route(ip, if_index);

1070

1253

if(route_added){

1244

1427

&decrypted_buffer, mc);

1245

1428

if(decrypted_buffer_size >= 0){

1246

1429

1430

clearerr(stdout);

1247

1431

written = 0;

1248

1432

while(written < (size_t) decrypted_buffer_size){

1249

1433

if(quit_now){

1265

1449

}

1266

1450

written += (size_t)ret;

1267

1451

}

1452

ret = fflush(stdout);

1453

if(ret != 0){

1454

int e = errno;

1455

if(debug){

1456

fprintf_plus(stderr, "Error writing encrypted data: %s\n",

1457

strerror(errno));

1458

}

1459

errno = e;

1460

goto mandos_end;

1461

}

1268

1462

retval = 0;

1269

1463

}

1270

1464

}

1274

1468

mandos_end:

1275

1469

{

1276

1470

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

fprintf_plus(stderr, "Failed to remove local route to %s on"

1471

if(not delete_local_route(ip, if_index)){

1472

fprintf_plus(stderr, "Failed to delete local route to %s on"

1279

1473

" interface %d", ip, if_index);

1280

1474

}

1281

1475

}

1283

1477

free(decrypted_buffer);

1284

1478

free(buffer);

1285

1479

if(tcp_sd >= 0){

1286

ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));

1480

ret = close(tcp_sd);

1287

1481

}

1288

1482

if(ret == -1){

1289

1483

if(e == 0){

1301

1495

return retval;

1302

1496

}

1303

1497

1304

__attribute__((nonnull))

1305

1498

static void resolve_callback(AvahiSServiceResolver *r,

1306

1499

AvahiIfIndex interface,

1307

1500

AvahiProtocol proto,

1444

1637

__attribute__((nonnull, warn_unused_result))

1445

1638

bool get_flags(const char *ifname, struct ifreq *ifr){

1446

1639

int ret;

1447

error_t ret_errno;

1640

int old_errno;

1448

1641

1449

1642

int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1450

1643

if(s < 0){

1451

ret_errno = errno;

1644

old_errno = errno;

1452

1645

perror_plus("socket");

1453

errno = ret_errno;

1646

errno = old_errno;

1454

1647

return false;

1455

1648

}

1456

strcpy(ifr->ifr_name, ifname);

1649

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1650

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1457

1651

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

1652

if(ret == -1){

1459

1653

if(debug){

1460

ret_errno = errno;

1654

old_errno = errno;

1461

1655

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1656

errno = old_errno;

1463

1657

}

1464

1658

return false;

1465

1659

}

1729

1923

return;

1730

1924

}

1731

1925

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1926

int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));

1927

if(devnull == -1){

1928

perror_plus("open(\"/dev/null\", O_RDONLY)");

1929

return;

1930

}

1734

1931

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1735

1932

runnable_hook, alphasort);

1736

#else /* not __GLIBC_PREREQ(2, 15) */

1737

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1738

alphasort);

1739

#endif /* not __GLIBC_PREREQ(2, 15) */

1740

#else /* not __GLIBC__ */

1741

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1744

1933

if(numhooks == -1){

1745

1934

perror_plus("scandir");

1935

close(devnull);

1746

1936

return;

1747

1937

}

1748

1938

struct dirent *direntry;

1749

1939

int ret;

1750

int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));

1751

if(devnull == -1){

1752

perror_plus("open(\"/dev/null\", O_RDONLY)");

1753

return;

1754

}

1755

1940

for(int i = 0; i < numhooks; i++){

1756

1941

direntry = direntries[i];

1757

1942

if(debug){

1828

2013

perror_plus("openat");

1829

2014

_exit(EXIT_FAILURE);

1830

2015

}

1831

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

2016

if(close(hookdir_fd) == -1){

1832

2017

perror_plus("close");

1833

2018

_exit(EXIT_FAILURE);

1834

2019

}

1837

2022

perror_plus("dup2(devnull, STDIN_FILENO)");

1838

2023

_exit(EX_OSERR);

1839

2024

}

1840

ret = (int)TEMP_FAILURE_RETRY(close(devnull));

2025

ret = close(devnull);

1841

2026

if(ret == -1){

1842

2027

perror_plus("close");

1843

2028

_exit(EX_OSERR);

1892

2077

free(direntry);

1893

2078

}

1894

2079

free(direntries);

1895

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

2080

if(close(hookdir_fd) == -1){

1896

2081

perror_plus("close");

1897

2082

} else {

1898

2083

hookdir_fd = -1;

1901

2086

}

1902

2087

1903

2088

__attribute__((nonnull, warn_unused_result))

1904

error_t bring_up_interface(const char *const interface,

1905

const float delay){

1906

error_t old_errno = errno;

2089

int bring_up_interface(const char *const interface,

2090

const float delay){

2091

int old_errno = errno;

1907

2092

int ret;

1908

2093

struct ifreq network;

1909

2094

unsigned int if_index = if_nametoindex(interface);

1919

2104

}

1920

2105

1921

2106

if(not interface_is_up(interface)){

1922

error_t ret_errno = 0, ioctl_errno = 0;

2107

int ret_errno = 0;

2108

int ioctl_errno = 0;

1923

2109

if(not get_flags(interface, &network)){

1924

2110

ret_errno = errno;

1925

2111

fprintf_plus(stderr, "Failed to get flags for interface "

1938

2124

}

1939

2125

1940

2126

if(quit_now){

1941

ret = (int)TEMP_FAILURE_RETRY(close(sd));

2127

ret = close(sd);

1942

2128

if(ret == -1){

1943

2129

perror_plus("close");

1944

2130

}

1994

2180

}

1995

2181

1996

2182

/* Close the socket */

1997

ret = (int)TEMP_FAILURE_RETRY(close(sd));

2183

ret = close(sd);

1998

2184

if(ret == -1){

1999

2185

perror_plus("close");

2000

2186

}

2012

2198

2013

2199

/* Sleep checking until interface is running.

2014

2200

Check every 0.25s, up to total time of delay */

2015

for(int i=0; i < delay * 4; i++){

2201

for(int i = 0; i < delay * 4; i++){

2016

2202

if(interface_is_running(interface)){

2017

2203

break;

2018

2204

}

2028

2214

}

2029

2215

2030

2216

__attribute__((nonnull, warn_unused_result))

2031

error_t take_down_interface(const char *const interface){

2032

error_t old_errno = errno;

2217

int take_down_interface(const char *const interface){

2218

int old_errno = errno;

2033

2219

struct ifreq network;

2034

2220

unsigned int if_index = if_nametoindex(interface);

2035

2221

if(if_index == 0){

2038

2224

return ENXIO;

2039

2225

}

2040

2226

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2227

int ret_errno = 0;

2228

int ioctl_errno = 0;

2042

2229

if(not get_flags(interface, &network) and debug){

2043

2230

ret_errno = errno;

2044

2231

fprintf_plus(stderr, "Failed to get flags for interface "

2082

2269

}

2083

2270

2084

2271

/* Close the socket */

2085

int ret = (int)TEMP_FAILURE_RETRY(close(sd));

2272

int ret = close(sd);

2086

2273

if(ret == -1){

2087

2274

perror_plus("close");

2088

2275

}

2103

2290

}

2104

2291

2105

2292

int main(int argc, char *argv[]){

2106

mandos_context mc = { .server = NULL, .dh_bits = 1024,

2107

.priority = "SECURE256:!CTYPE-X.509:"

2108

"+CTYPE-OPENPGP", .current_server = NULL,

2109

.interfaces = NULL, .interfaces_size = 0 };

2293

mandos_context mc = { .server = NULL, .dh_bits = 0,

2294

.priority = "SECURE256:!CTYPE-X.509"

2295

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2296

.current_server = NULL, .interfaces = NULL,

2297

.interfaces_size = 0 };

2110

2298

AvahiSServiceBrowser *sb = NULL;

2111

2299

error_t ret_errno;

2112

2300

int ret;

2121

2309

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2122

2310

const char *seckey = PATHDIR "/" SECKEY;

2123

2311

const char *pubkey = PATHDIR "/" PUBKEY;

2312

const char *dh_params_file = NULL;

2124

2313

char *interfaces_hooks = NULL;

2125

2314

2126

2315

bool gnutls_initialized = false;

2179

2368

.doc = "Bit length of the prime number used in the"

2180

2369

" Diffie-Hellman key exchange",

2181

2370

.group = 2 },

2371

{ .name = "dh-params", .key = 134,

2372

.arg = "FILE",

2373

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2374

" for the Diffie-Hellman key exchange",

2375

.group = 2 },

2182

2376

{ .name = "priority", .key = 130,

2183

2377

.arg = "STRING",

2184

2378

.doc = "GnuTLS priority string for the TLS handshake",

2239

2433

}

2240

2434

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

2241

2435

break;

2436

case 134: /* --dh-params */

2437

dh_params_file = arg;

2438

break;

2242

2439

case 130: /* --priority */

2243

2440

mc.priority = arg;

2244

2441

break;

2284

2481

.args_doc = "",

2285

2482

.doc = "Mandos client -- Get and decrypt"

2286

2483

" passwords from a Mandos server" };

2287

ret = argp_parse(&argp, argc, argv,

2288

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2289

switch(ret){

2484

ret_errno = argp_parse(&argp, argc, argv,

2485

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2486

switch(ret_errno){

2290

2487

case 0:

2291

2488

break;

2292

2489

case ENOMEM:

2293

2490

default:

2294

errno = ret;

2491

errno = ret_errno;

2295

2492

perror_plus("argp_parse");

2296

2493

exitcode = EX_OSERR;

2297

2494

goto end;

2303

2500

2304

2501

{

2305

2502

/* Work around Debian bug #633582:

2306

<http://bugs.debian.org/633582> */

2503

<https://bugs.debian.org/633582> */

2307

2504

2308

2505

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2506

ret = raise_privileges();

2507

if(ret != 0){

2508

errno = ret;

2312

2509

perror_plus("Failed to raise privileges");

2313

2510

} else {

2314

2511

struct stat st;

2330

2527

}

2331

2528

}

2332

2529

}

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

2530

close(seckey_fd);

2334

2531

}

2335

2532

}

2336

2533

2351

2548

}

2352

2549

}

2353

2550

}

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2551

close(pubkey_fd);

2552

}

2553

}

2554

2555

if(dh_params_file != NULL

2556

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2557

int dhparams_fd = open(dh_params_file, O_RDONLY);

2558

if(dhparams_fd == -1){

2559

perror_plus("open");

2560

} else {

2561

ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));

2562

if(ret == -1){

2563

perror_plus("fstat");

2564

} else {

2565

if(S_ISREG(st.st_mode)

2566

and st.st_uid == 0 and st.st_gid == 0){

2567

ret = fchown(dhparams_fd, uid, gid);

2568

if(ret == -1){

2569

perror_plus("fchown");

2570

}

2571

}

2572

}

2573

close(dhparams_fd);

2355

2574

}

2356

2575

}

2357

2576

2358

2577

/* Lower privileges */

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2578

ret = lower_privileges();

2579

if(ret != 0){

2580

errno = ret;

2362

2581

perror_plus("Failed to lower privileges");

2363

2582

}

2364

2583

}

2534

2753

errno = bring_up_interface(interface, delay);

2535

2754

if(not interface_was_up){

2536

2755

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2756

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2757

" %s\n", interface, strerror(errno));

2538

2758

} else {

2539

2759

errno = argz_add(&interfaces_to_take_down,

2540

2760

&interfaces_to_take_down_size,

2563

2783

goto end;

2564

2784

}

2565

2785

2566

ret = init_gnutls_global(pubkey, seckey, &mc);

2786

ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);

2567

2787

if(ret == -1){

2568

2788

fprintf_plus(stderr, "init_gnutls_global failed\n");

2569

2789

exitcode = EX_UNAVAILABLE;

2691

2911

2692

2912

/* Allocate a new server */

2693

2913

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

2914

&config, NULL, NULL, &ret);

2695

2915

2696

2916

/* Free the Avahi configuration data */

2697

2917

avahi_server_config_free(&config);

2700

2920

/* Check if creating the Avahi server object succeeded */

2701

2921

if(mc.server == NULL){

2702

2922

fprintf_plus(stderr, "Failed to create Avahi server: %s\n",

2703

avahi_strerror(ret_errno));

2923

avahi_strerror(ret));

2704

2924

exitcode = EX_UNAVAILABLE;

2705

2925

goto end;

2706

2926

}

2741

2961

end:

2742

2962

2743

2963

if(debug){

2744

fprintf_plus(stderr, "%s exiting\n", argv[0]);

2964

if(signal_received){

2965

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

2966

argv[0], signal_received,

2967

strsignal(signal_received));

2968

} else {

2969

fprintf_plus(stderr, "%s exiting\n", argv[0]);

2970

}

2745

2971

}

2746

2972

2747

2973

/* Cleanup things */

2758

2984

2759

2985

if(gnutls_initialized){

2760

2986

gnutls_certificate_free_credentials(mc.cred);

2761

gnutls_global_deinit();

2762

2987

gnutls_dh_params_deinit(mc.dh_params);

2763

2988

}

2764

2989

2787

3012

2788

3013

/* Re-raise privileges */

2789

3014

{

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

3015

ret = raise_privileges();

3016

if(ret != 0){

3017

errno = ret;

2793

3018

perror_plus("Failed to raise privileges");

2794

3019

} else {

2795

3020

2800

3025

/* Take down the network interfaces which were brought up */

2801

3026

{

2802

3027

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

3028

while((interface = argz_next(interfaces_to_take_down,

3029

interfaces_to_take_down_size,

3030

interface))){

3031

ret = take_down_interface(interface);

3032

if(ret != 0){

3033

errno = ret;

2809

3034

perror_plus("Failed to take down interface");

2810

3035

}

2811

3036

}

2816

3041

}

2817

3042

}

2818

3043

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

3044

ret = lower_privileges_permanently();

3045

if(ret != 0){

3046

errno = ret;

2822

3047

perror_plus("Failed to lower privileges permanently");

2823

3048

}

2824

3049

}

2826

3051

free(interfaces_to_take_down);

2827

3052

free(interfaces_hooks);

2828

3053

3054

void clean_dir_at(int base, const char * const dirname,

3055

uintmax_t level){

3056

struct dirent **direntries = NULL;

3057

int dret;

3058

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3059

O_RDONLY

3060

| O_NOFOLLOW

3061

| O_DIRECTORY

3062

| O_PATH));

3063

if(dir_fd == -1){

3064

perror_plus("open");

3065

return;

3066

}

3067

int numentries = scandirat(dir_fd, ".", &direntries,

3068

notdotentries, alphasort);

3069

if(numentries >= 0){

3070

for(int i = 0; i < numentries; i++){

3071

if(debug){

3072

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3073

dirname, direntries[i]->d_name);

3074

}

3075

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3076

if(dret == -1){

3077

if(errno == EISDIR){

3078

dret = unlinkat(dir_fd, direntries[i]->d_name,

3079

AT_REMOVEDIR);

3080

}

3081

if((dret == -1) and (errno == ENOTEMPTY)

3082

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3083

== 0) and (level == 0)){

3084

/* Recurse only in this special case */

3085

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3086

dret = 0;

3087

}

3088

if((dret == -1) and (errno != ENOENT)){

3089

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3090

direntries[i]->d_name, strerror(errno));

3091

}

3092

}

3093

free(direntries[i]);

3094

}

3095

3096

/* need to clean even if 0 because man page doesn't specify */

3097

free(direntries);

3098

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3099

if(dret == -1 and errno != ENOENT){

3100

perror_plus("rmdir");

3101

}

3102

} else {

3103

perror_plus("scandirat");

3104

}

3105

close(dir_fd);

3106

}

3107

2829

3108

/* Removes the GPGME temp directory and all files inside */

2830

3109

if(tempdir != NULL){

2831

struct dirent **direntries = NULL;

2832

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

int numentries = scandirat(tempdir_fd, ".", &direntries,

2842

notdotentries, alphasort);

2843

#else /* not __GLIBC_PREREQ(2, 15) */

2844

int numentries = scandir(tempdir, &direntries, notdotentries,

2845

alphasort);

2846

#endif /* not __GLIBC_PREREQ(2, 15) */

2847

#else /* not __GLIBC__ */

2848

int numentries = scandir(tempdir, &direntries, notdotentries,

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

for(int i = 0; i < numentries; i++){

2853

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2854

if(ret == -1){

2855

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2856

" \"%s\", 0): %s\n", tempdir,

2857

direntries[i]->d_name, strerror(errno));

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

/* need to clean even if 0 because man page doesn't specify */

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

if(ret == -1 and errno != ENOENT){

2869

perror_plus("rmdir");

2870

}

2871

}

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

2873

}

3110

clean_dir_at(-1, tempdir, 0);

2874

3111

}

2875

3112

2876

3113

if(quit_now){