/mandos/release : revision 237.7.488

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

*/

32

33

/* Needed by GPGME, specifically gpgme_data_seek() */

33

34

#ifndef _LARGEFILE_SOURCE

34

35

#define _LARGEFILE_SOURCE

35

#endif

36

#endif /* not _LARGEFILE_SOURCE */

36

37

#ifndef _FILE_OFFSET_BITS

37

38

#define _FILE_OFFSET_BITS 64

38

#endif

39

#endif /* not _FILE_OFFSET_BITS */

39

40

41

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */

41

42

43

#include <stdio.h> /* fprintf(), stderr, fwrite(),

43

stdout, ferror(), remove() */

44

stdout, ferror() */

44

45

#include <stdint.h> /* uint16_t, uint32_t, intptr_t */

45

46

#include <stddef.h> /* NULL, size_t, ssize_t */

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() */

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,

73

79

*/

74

80

#include <unistd.h> /* close(), SEEK_SET, off_t, write(),

75

81

getuid(), getgid(), seteuid(),

76

setgid(), pause(), _exit() */

82

setgid(), pause(), _exit(),

83

unlinkat() */

77

84

#include <arpa/inet.h> /* inet_pton(), htons() */

78

85

#include <iso646.h> /* not, or, and */

79

86

#include <argp.h> /* struct argp_option, error_t, struct

141

148

static const char sys_class_net[] = "/sys/class/net";

142

149

char *connect_to = NULL;

143

150

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

144

152

uid_t uid = 65534;

145

153

gid_t gid = 65534;

146

154

232

240

.af = af };

233

241

if(new_server->ip == NULL){

234

242

perror_plus("strdup");

243

free(new_server);

235

244

return false;

236

245

}

237

246

ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));

238

247

if(ret == -1){

239

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

free((char *)(new_server->ip));

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

240

258

return false;

241

259

}

242

260

/* Special case of first server */

293

311

return false;

294

312

}

295

313

296

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

314

ret = close(fd);

297

315

if(ret == -1){

298

316

perror_plus("close");

299

317

}

481

499

return plaintext_length;

482

500

}

483

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

484

509

__attribute__((warn_unused_result))

485

510

static const char *safer_gnutls_strerror(int value){

486

511

const char *ret = gnutls_strerror(value);

487

if(ret == NULL)

488

ret = "(unknown)";

489

return ret;

512

return safe_string(ret);

490

513

}

491

514

492

515

/* GnuTLS log function callback */

496

519

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

497

520

}

498

521

499

__attribute__((nonnull, warn_unused_result))

522

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

500

523

static int init_gnutls_global(const char *pubkeyfilename,

501

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

502

526

mandos_context *mc){

503

527

int ret;

528

unsigned int uret;

504

529

505

530

if(debug){

506

531

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

507

532

}

508

533

509

ret = gnutls_global_init();

510

if(ret != GNUTLS_E_SUCCESS){

511

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

512

safer_gnutls_strerror(ret));

513

return -1;

514

}

515

516

534

if(debug){

517

535

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

518

536

* - GnuTLS manual

526

544

if(ret != GNUTLS_E_SUCCESS){

527

545

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

528

546

safer_gnutls_strerror(ret));

529

gnutls_global_deinit();

530

547

return -1;

531

548

}

532

549

557

574

safer_gnutls_strerror(ret));

558

575

goto globalfail;

559

576

}

560

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

561

if(ret != GNUTLS_E_SUCCESS){

562

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

563

safer_gnutls_strerror(ret));

564

goto globalfail;

565

}

566

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

close(dhpfile);

617

if(params.data == NULL){

618

dhparamsfilename = NULL;

619

}

620

if(dhparamsfilename == NULL){

621

break;

622

}

623

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

624

GNUTLS_X509_FMT_PEM);

625

if(ret != GNUTLS_E_SUCCESS){

626

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

627

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

628

safer_gnutls_strerror(ret));

629

dhparamsfilename = NULL;

630

}

631

free(params.data);

632

} while(false);

633

}

634

if(dhparamsfilename == NULL){

635

if(mc->dh_bits == 0){

636

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

637

/* Try to read the private key file */

638

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

639

do {

640

int secfile = open(seckeyfilename, O_RDONLY);

641

if(secfile == -1){

642

perror_plus("open");

643

break;

644

}

645

size_t buffer_capacity = 0;

646

while(true){

647

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

648

(size_t)buffer.size,

649

(size_t)buffer_capacity);

650

if(buffer_capacity == 0){

651

perror_plus("incbuffer");

652

free(buffer.data);

653

buffer.data = NULL;

654

break;

655

}

656

ssize_t bytes_read = read(secfile,

657

buffer.data + buffer.size,

658

BUFFER_SIZE);

659

/* EOF */

660

if(bytes_read == 0){

661

break;

662

}

663

/* check bytes_read for failure */

664

if(bytes_read < 0){

665

perror_plus("read");

666

free(buffer.data);

667

buffer.data = NULL;

668

break;

669

}

670

buffer.size += (unsigned int)bytes_read;

671

}

672

close(secfile);

673

} while(false);

674

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

675

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

676

if(buffer.data != NULL){

677

{

678

gnutls_openpgp_privkey_t privkey = NULL;

679

ret = gnutls_openpgp_privkey_init(&privkey);

680

if(ret != GNUTLS_E_SUCCESS){

681

fprintf_plus(stderr, "Error initializing OpenPGP key"

682

" structure: %s",

683

safer_gnutls_strerror(ret));

684

free(buffer.data);

685

buffer.data = NULL;

686

} else {

687

ret = gnutls_openpgp_privkey_import

688

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

689

if(ret != GNUTLS_E_SUCCESS){

690

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

691

safer_gnutls_strerror(ret));

692

privkey = NULL;

693

}

694

free(buffer.data);

695

buffer.data = NULL;

696

if(privkey != NULL){

697

/* Use private key to suggest an appropriate

698

sec_param */

699

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

700

gnutls_openpgp_privkey_deinit(privkey);

701

if(debug){

702

fprintf_plus(stderr, "This OpenPGP key implies using"

703

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

704

safe_string(gnutls_sec_param_get_name

705

(sec_param)));

706

}

707

}

708

}

709

}

710

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

711

/* Err on the side of caution */

712

sec_param = GNUTLS_SEC_PARAM_ULTRA;

713

if(debug){

714

fprintf_plus(stderr, "Falling back to security parameter"

715

" \"%s\"\n",

716

safe_string(gnutls_sec_param_get_name

717

(sec_param)));

718

}

719

}

720

}

721

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

722

if(uret != 0){

723

mc->dh_bits = uret;

724

if(debug){

725

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

726

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

727

safe_string(gnutls_sec_param_get_name

728

(sec_param)),

729

mc->dh_bits);

730

}

731

} else {

732

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

733

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

734

safe_string(gnutls_sec_param_get_name

735

(sec_param)),

736

safer_gnutls_strerror(ret));

737

goto globalfail;

738

}

739

} else if(debug){

740

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

741

mc->dh_bits);

742

}

743

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

744

if(ret != GNUTLS_E_SUCCESS){

745

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

746

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

747

safer_gnutls_strerror(ret));

748

goto globalfail;

749

}

750

}

567

751

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

568

752

569

753

return 0;

571

755

globalfail:

572

756

573

757

gnutls_certificate_free_credentials(mc->cred);

574

gnutls_global_deinit();

575

758

gnutls_dh_params_deinit(mc->dh_params);

576

759

return -1;

577

760

}

629

812

/* ignore client certificate if any. */

630

813

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

631

814

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

633

634

815

return 0;

635

816

}

636

817

638

819

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

639

820

__attribute__((unused)) const char *txt){}

640

821

822

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

823

__attribute__((warn_unused_result))

824

int raise_privileges(void){

825

int old_errno = errno;

826

int ret = 0;

827

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

828

ret = errno;

829

}

830

errno = old_errno;

831

return ret;

832

}

833

834

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

835

__attribute__((warn_unused_result))

836

int raise_privileges_permanently(void){

837

int old_errno = errno;

838

int ret = raise_privileges();

839

if(ret != 0){

840

errno = old_errno;

841

return ret;

842

}

843

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

844

ret = errno;

845

}

846

errno = old_errno;

847

return ret;

848

}

849

850

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

851

__attribute__((warn_unused_result))

852

int lower_privileges(void){

853

int old_errno = errno;

854

int ret = 0;

855

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

856

ret = errno;

857

}

858

errno = old_errno;

859

return ret;

860

}

861

862

/* Lower privileges permanently */

863

__attribute__((warn_unused_result))

864

int lower_privileges_permanently(void){

865

int old_errno = errno;

866

int ret = 0;

867

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

868

ret = errno;

869

}

870

errno = old_errno;

871

return ret;

872

}

873

874

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

875

__attribute__((nonnull, warn_unused_result))

876

static bool add_delete_local_route(const bool add,

877

const char *address,

878

AvahiIfIndex if_index){

879

int ret;

880

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

881

char add_arg[] = "add";

882

char delete_arg[] = "delete";

883

char debug_flag[] = "--debug";

884

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

885

if(pluginhelperdir == NULL){

886

if(debug){

887

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

888

" variable not set; cannot run helper\n");

889

}

890

return false;

891

}

892

893

char interface[IF_NAMESIZE];

894

if(if_indextoname((unsigned int)if_index, interface) == NULL){

895

perror_plus("if_indextoname");

896

return false;

897

}

898

899

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

900

if(devnull == -1){

901

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

902

return false;

903

}

904

pid_t pid = fork();

905

if(pid == 0){

906

/* Child */

907

/* Raise privileges */

908

errno = raise_privileges_permanently();

909

if(errno != 0){

910

perror_plus("Failed to raise privileges");

911

/* _exit(EX_NOPERM); */

912

} else {

913

/* Set group */

914

errno = 0;

915

ret = setgid(0);

916

if(ret == -1){

917

perror_plus("setgid");

918

_exit(EX_NOPERM);

919

}

920

/* Reset supplementary groups */

921

errno = 0;

922

ret = setgroups(0, NULL);

923

if(ret == -1){

924

perror_plus("setgroups");

925

_exit(EX_NOPERM);

926

}

927

}

928

ret = dup2(devnull, STDIN_FILENO);

929

if(ret == -1){

930

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

931

_exit(EX_OSERR);

932

}

933

ret = close(devnull);

934

if(ret == -1){

935

perror_plus("close");

936

_exit(EX_OSERR);

937

}

938

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

939

if(ret == -1){

940

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

941

_exit(EX_OSERR);

942

}

943

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

944

O_RDONLY

945

| O_DIRECTORY

946

| O_PATH

947

| O_CLOEXEC));

948

if(helperdir_fd == -1){

949

perror_plus("open");

950

_exit(EX_UNAVAILABLE);

951

}

952

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

953

helper, O_RDONLY));

954

if(helper_fd == -1){

955

perror_plus("openat");

956

close(helperdir_fd);

957

_exit(EX_UNAVAILABLE);

958

}

959

close(helperdir_fd);

960

#ifdef __GNUC__

961

#pragma GCC diagnostic push

962

#pragma GCC diagnostic ignored "-Wcast-qual"

963

#endif

964

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

965

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

966

interface, debug ? debug_flag : NULL, NULL },

967

environ) == -1){

968

#ifdef __GNUC__

969

#pragma GCC diagnostic pop

970

#endif

971

perror_plus("fexecve");

972

_exit(EXIT_FAILURE);

973

}

974

}

975

if(pid == -1){

976

perror_plus("fork");

977

return false;

978

}

979

int status;

980

pid_t pret = -1;

981

errno = 0;

982

do {

983

pret = waitpid(pid, &status, 0);

984

if(pret == -1 and errno == EINTR and quit_now){

985

int errno_raising = 0;

986

if((errno = raise_privileges()) != 0){

987

errno_raising = errno;

988

perror_plus("Failed to raise privileges in order to"

989

" kill helper program");

990

}

991

if(kill(pid, SIGTERM) == -1){

992

perror_plus("kill");

993

}

994

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

995

perror_plus("Failed to lower privileges after killing"

996

" helper program");

997

}

998

return false;

999

}

1000

} while(pret == -1 and errno == EINTR);

1001

if(pret == -1){

1002

perror_plus("waitpid");

1003

return false;

1004

}

1005

if(WIFEXITED(status)){

1006

if(WEXITSTATUS(status) != 0){

1007

fprintf_plus(stderr, "Error: iprouteadddel exited"

1008

" with status %d\n", WEXITSTATUS(status));

1009

return false;

1010

}

1011

return true;

1012

}

1013

if(WIFSIGNALED(status)){

1014

fprintf_plus(stderr, "Error: iprouteadddel died by"

1015

" signal %d\n", WTERMSIG(status));

1016

return false;

1017

}

1018

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

1019

return false;

1020

}

1021

1022

__attribute__((nonnull, warn_unused_result))

1023

static bool add_local_route(const char *address,

1024

AvahiIfIndex if_index){

1025

if(debug){

1026

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

1027

}

1028

return add_delete_local_route(true, address, if_index);

1029

}

1030

1031

__attribute__((nonnull, warn_unused_result))

1032

static bool delete_local_route(const char *address,

1033

AvahiIfIndex if_index){

1034

if(debug){

1035

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

1036

}

1037

return add_delete_local_route(false, address, if_index);

1038

}

1039

641

1040

/* Called when a Mandos server is found */

642

1041

__attribute__((nonnull, warn_unused_result))

643

1042

static int start_mandos_communication(const char *ip, in_port_t port,

654

1053

int retval = -1;

655

1054

gnutls_session_t session;

656

1055

int pf; /* Protocol family */

1056

bool route_added = false;

657

1057

658

1058

errno = 0;

659

1059

681

1081

bool match = false;

682

1082

{

683

1083

char *interface = NULL;

684

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

685

interface))){

1084

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

1085

mc->interfaces_size,

1086

interface))){

686

1087

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

687

1088

match = true;

688

1089

break;

717

1118

PRIuMAX "\n", ip, (uintmax_t)port);

718

1119

}

719

1120

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

1121

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

721

1122

if(tcp_sd < 0){

722

1123

int e = errno;

723

1124

perror_plus("socket");

730

1131

goto mandos_end;

731

1132

}

732

1133

733

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

734

1134

if(af == AF_INET6){

735

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

736

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

1135

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

1136

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

1137

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

737

1138

} else { /* IPv4 */

738

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

739

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

1139

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

1140

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

1141

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

740

1142

}

741

1143

if(ret < 0 ){

742

1144

int e = errno;

812

1214

goto mandos_end;

813

1215

}

814

1216

815

if(af == AF_INET6){

816

ret = connect(tcp_sd, (struct sockaddr *)&to,

817

sizeof(struct sockaddr_in6));

818

} else {

819

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

820

sizeof(struct sockaddr_in));

821

}

822

if(ret < 0){

823

if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){

824

int e = errno;

825

perror_plus("connect");

826

errno = e;

827

}

828

goto mandos_end;

829

}

830

831

if(quit_now){

832

errno = EINTR;

833

goto mandos_end;

1217

while(true){

1218

if(af == AF_INET6){

1219

ret = connect(tcp_sd, (struct sockaddr *)&to,

1220

sizeof(struct sockaddr_in6));

1221

} else {

1222

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

1223

sizeof(struct sockaddr_in));

1224

}

1225

if(ret < 0){

1226

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

1227

and if_index != AVAHI_IF_UNSPEC

1228

and connect_to == NULL

1229

and not route_added and

1230

((af == AF_INET6 and not

1231

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1232

&to)->sin6_addr)))

1233

or (af == AF_INET and

1234

/* Not a a IPv4LL address */

1235

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1236

& 0xFFFF0000L) != 0xA9FE0000L))){

1237

/* Work around Avahi bug - Avahi does not announce link-local

1238

addresses if it has a global address, so local hosts with

1239

*only* a link-local address (e.g. Mandos clients) cannot

1240

connect to a Mandos server announced by Avahi on a server

1241

host with a global address. Work around this by retrying

1242

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

1243

1244

Avahi bug reference:

1245

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

1246

https://bugs.debian.org/587961

1247

*/

1248

if(debug){

1249

fprintf_plus(stderr, "Mandos server unreachable, trying"

1250

" direct route\n");

1251

}

1252

int e = errno;

1253

route_added = add_local_route(ip, if_index);

1254

if(route_added){

1255

continue;

1256

}

1257

errno = e;

1258

}

1259

if(errno != ECONNREFUSED or debug){

1260

int e = errno;

1261

perror_plus("connect");

1262

errno = e;

1263

}

1264

goto mandos_end;

1265

}

1266

1267

if(quit_now){

1268

errno = EINTR;

1269

goto mandos_end;

1270

}

1271

break;

834

1272

}

835

1273

836

1274

const char *out = mandos_protocol_version;

990

1428

&decrypted_buffer, mc);

991

1429

if(decrypted_buffer_size >= 0){

992

1430

1431

clearerr(stdout);

993

1432

written = 0;

994

1433

while(written < (size_t) decrypted_buffer_size){

995

1434

if(quit_now){

1011

1450

}

1012

1451

written += (size_t)ret;

1013

1452

}

1453

ret = fflush(stdout);

1454

if(ret != 0){

1455

int e = errno;

1456

if(debug){

1457

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

1458

strerror(errno));

1459

}

1460

errno = e;

1461

goto mandos_end;

1462

}

1014

1463

retval = 0;

1015

1464

}

1016

1465

}

1019

1468

1020

1469

mandos_end:

1021

1470

{

1471

if(route_added){

1472

if(not delete_local_route(ip, if_index)){

1473

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

1474

" interface %d", ip, if_index);

1475

}

1476

}

1022

1477

int e = errno;

1023

1478

free(decrypted_buffer);

1024

1479

free(buffer);

1025

1480

if(tcp_sd >= 0){

1026

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

1481

ret = close(tcp_sd);

1027

1482

}

1028

1483

if(ret == -1){

1029

1484

if(e == 0){

1041

1496

return retval;

1042

1497

}

1043

1498

1044

__attribute__((nonnull))

1045

1499

static void resolve_callback(AvahiSServiceResolver *r,

1046

1500

AvahiIfIndex interface,

1047

1501

AvahiProtocol proto,

1064

1518

timed out */

1065

1519

1066

1520

if(quit_now){

1521

avahi_s_service_resolver_free(r);

1067

1522

return;

1068

1523

}

1069

1524

1183

1638

__attribute__((nonnull, warn_unused_result))

1184

1639

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

1185

1640

int ret;

1186

error_t ret_errno;

1641

int old_errno;

1187

1642

1188

1643

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

1189

1644

if(s < 0){

1190

ret_errno = errno;

1645

old_errno = errno;

1191

1646

perror_plus("socket");

1192

errno = ret_errno;

1647

errno = old_errno;

1193

1648

return false;

1194

1649

}

1195

strcpy(ifr->ifr_name, ifname);

1650

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

1651

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

1196

1652

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1197

1653

if(ret == -1){

1198

1654

if(debug){

1199

ret_errno = errno;

1655

old_errno = errno;

1200

1656

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1657

errno = old_errno;

1202

1658

}

1659

close(s);

1203

1660

return false;

1204

1661

}

1662

close(s);

1205

1663

return true;

1206

1664

}

1207

1665

1335

1793

sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

1336

1794

"abcdefghijklmnopqrstuvwxyz"

1337

1795

"0123456789"

1338

"_-");

1796

"_.-");

1339

1797

if((direntry->d_name)[sret] != '\0'){

1340

1798

/* Contains non-allowed characters */

1341

1799

if(debug){

1345

1803

return 0;

1346

1804

}

1347

1805

1348

char *fullname = NULL;

1349

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1350

if(ret < 0){

1351

perror_plus("asprintf");

1352

return 0;

1353

}

1354

1355

ret = stat(fullname, &st);

1806

ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);

1356

1807

if(ret == -1){

1357

1808

if(debug){

1358

1809

perror_plus("Could not stat hook");

1456

1907

}

1457

1908

}

1458

1909

1459

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

1460

__attribute__((warn_unused_result))

1461

error_t raise_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

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

1473

__attribute__((warn_unused_result))

1474

error_t raise_privileges_permanently(void){

1475

error_t old_errno = errno;

1476

error_t ret_errno = raise_privileges();

1477

if(ret_errno != 0){

1478

errno = old_errno;

1479

return ret_errno;

1480

}

1481

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

1482

ret_errno = errno;

1483

perror_plus("seteuid");

1484

}

1485

errno = old_errno;

1486

return ret_errno;

1487

}

1488

1489

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

1490

__attribute__((warn_unused_result))

1491

error_t lower_privileges(void){

1492

error_t old_errno = errno;

1493

error_t ret_errno = 0;

1494

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

1495

ret_errno = errno;

1496

perror_plus("seteuid");

1497

}

1498

errno = old_errno;

1499

return ret_errno;

1500

}

1501

1502

/* Lower privileges permanently */

1503

__attribute__((warn_unused_result))

1504

error_t lower_privileges_permanently(void){

1505

error_t old_errno = errno;

1506

error_t ret_errno = 0;

1507

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

1508

ret_errno = errno;

1509

perror_plus("setuid");

1510

}

1511

errno = old_errno;

1512

return ret_errno;

1513

}

1514

1515

1910

__attribute__((nonnull))

1516

1911

void run_network_hooks(const char *mode, const char *interface,

1517

1912

const float delay){

1518

struct dirent **direntries;

1519

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

1520

alphasort);

1913

struct dirent **direntries = NULL;

1914

if(hookdir_fd == -1){

1915

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1916

| O_CLOEXEC);

1917

if(hookdir_fd == -1){

1918

if(errno == ENOENT){

1919

if(debug){

1920

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1921

" found\n", hookdir);

1922

}

1923

} else {

1924

perror_plus("open");

1925

}

1926

return;

1927

}

1928

}

1929

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

1930

if(devnull == -1){

1931

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

1932

return;

1933

}

1934

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

1935

runnable_hook, alphasort);

1521

1936

if(numhooks == -1){

1522

if(errno == ENOENT){

1523

if(debug){

1524

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1525

" found\n", hookdir);

1526

}

1527

} else {

1528

perror_plus("scandir");

1937

perror_plus("scandir");

1938

close(devnull);

1939

return;

1940

}

1941

struct dirent *direntry;

1942

int ret;

1943

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

1944

direntry = direntries[i];

1945

if(debug){

1946

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1947

direntry->d_name);

1529

1948

}

1530

} else {

1531

struct dirent *direntry;

1532

int ret;

1533

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

1534

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

1535

direntry = direntries[i];

1536

char *fullname = NULL;

1537

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1538

if(ret < 0){

1949

pid_t hook_pid = fork();

1950

if(hook_pid == 0){

1951

/* Child */

1952

/* Raise privileges */

1953

errno = raise_privileges_permanently();

1954

if(errno != 0){

1955

perror_plus("Failed to raise privileges");

1956

_exit(EX_NOPERM);

1957

}

1958

/* Set group */

1959

errno = 0;

1960

ret = setgid(0);

1961

if(ret == -1){

1962

perror_plus("setgid");

1963

_exit(EX_NOPERM);

1964

}

1965

/* Reset supplementary groups */

1966

errno = 0;

1967

ret = setgroups(0, NULL);

1968

if(ret == -1){

1969

perror_plus("setgroups");

1970

_exit(EX_NOPERM);

1971

}

1972

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1973

if(ret == -1){

1974

perror_plus("setenv");

1975

_exit(EX_OSERR);

1976

}

1977

ret = setenv("DEVICE", interface, 1);

1978

if(ret == -1){

1979

perror_plus("setenv");

1980

_exit(EX_OSERR);

1981

}

1982

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1983

if(ret == -1){

1984

perror_plus("setenv");

1985

_exit(EX_OSERR);

1986

}

1987

ret = setenv("MODE", mode, 1);

1988

if(ret == -1){

1989

perror_plus("setenv");

1990

_exit(EX_OSERR);

1991

}

1992

char *delaystring;

1993

ret = asprintf(&delaystring, "%f", (double)delay);

1994

if(ret == -1){

1539

1995

perror_plus("asprintf");

1540

continue;

1541

}

1542

if(debug){

1543

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1544

direntry->d_name);

1545

}

1546

pid_t hook_pid = fork();

1547

if(hook_pid == 0){

1548

/* Child */

1549

/* Raise privileges */

1550

if(raise_privileges_permanently() != 0){

1551

perror_plus("Failed to raise privileges");

1552

_exit(EX_NOPERM);

1553

}

1554

/* Set group */

1555

errno = 0;

1556

ret = setgid(0);

1557

if(ret == -1){

1558

perror_plus("setgid");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Reset supplementary groups */

1562

errno = 0;

1563

ret = setgroups(0, NULL);

1564

if(ret == -1){

1565

perror_plus("setgroups");

1566

_exit(EX_NOPERM);

1567

}

1568

ret = dup2(devnull, STDIN_FILENO);

1569

if(ret == -1){

1570

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

1571

_exit(EX_OSERR);

1572

}

1573

ret = close(devnull);

1574

if(ret == -1){

1575

perror_plus("close");

1576

_exit(EX_OSERR);

1577

}

1578

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1579

if(ret == -1){

1580

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

1581

_exit(EX_OSERR);

1582

}

1583

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1584

if(ret == -1){

1585

perror_plus("setenv");

1586

_exit(EX_OSERR);

1587

}

1588

ret = setenv("DEVICE", interface, 1);

1589

if(ret == -1){

1590

perror_plus("setenv");

1591

_exit(EX_OSERR);

1592

}

1593

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1594

if(ret == -1){

1595

perror_plus("setenv");

1596

_exit(EX_OSERR);

1597

}

1598

ret = setenv("MODE", mode, 1);

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

char *delaystring;

1604

ret = asprintf(&delaystring, "%f", (double)delay);

1605

if(ret == -1){

1606

perror_plus("asprintf");

1607

_exit(EX_OSERR);

1608

}

1609

ret = setenv("DELAY", delaystring, 1);

1610

if(ret == -1){

1611

free(delaystring);

1612

perror_plus("setenv");

1613

_exit(EX_OSERR);

1614

}

1996

_exit(EX_OSERR);

1997

}

1998

ret = setenv("DELAY", delaystring, 1);

1999

if(ret == -1){

1615

2000

free(delaystring);

1616

if(connect_to != NULL){

1617

ret = setenv("CONNECT", connect_to, 1);

1618

if(ret == -1){

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

}

1623

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1624

perror_plus("execl");

1625

_exit(EXIT_FAILURE);

1626

}

2001

perror_plus("setenv");

2002

_exit(EX_OSERR);

2003

}

2004

free(delaystring);

2005

if(connect_to != NULL){

2006

ret = setenv("CONNECT", connect_to, 1);

2007

if(ret == -1){

2008

perror_plus("setenv");

2009

_exit(EX_OSERR);

2010

}

2011

}

2012

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

2013

direntry->d_name,

2014

O_RDONLY));

2015

if(hook_fd == -1){

2016

perror_plus("openat");

2017

_exit(EXIT_FAILURE);

2018

}

2019

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

2020

perror_plus("close");

2021

_exit(EXIT_FAILURE);

2022

}

2023

ret = dup2(devnull, STDIN_FILENO);

2024

if(ret == -1){

2025

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

2026

_exit(EX_OSERR);

2027

}

2028

ret = close(devnull);

2029

if(ret == -1){

2030

perror_plus("close");

2031

_exit(EX_OSERR);

2032

}

2033

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2034

if(ret == -1){

2035

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

2036

_exit(EX_OSERR);

2037

}

2038

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

2039

environ) == -1){

2040

perror_plus("fexecve");

2041

_exit(EXIT_FAILURE);

2042

}

2043

} else {

2044

if(hook_pid == -1){

2045

perror_plus("fork");

2046

free(direntry);

2047

continue;

2048

}

2049

int status;

2050

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

2051

perror_plus("waitpid");

2052

free(direntry);

2053

continue;

2054

}

2055

if(WIFEXITED(status)){

2056

if(WEXITSTATUS(status) != 0){

2057

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

2058

" with status %d\n", direntry->d_name,

2059

WEXITSTATUS(status));

2060

free(direntry);

2061

continue;

2062

}

2063

} else if(WIFSIGNALED(status)){

2064

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

2065

" signal %d\n", direntry->d_name,

2066

WTERMSIG(status));

2067

free(direntry);

2068

continue;

1627

2069

} else {

1628

int status;

1629

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1630

perror_plus("waitpid");

1631

free(fullname);

1632

continue;

1633

}

1634

if(WIFEXITED(status)){

1635

if(WEXITSTATUS(status) != 0){

1636

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1637

" with status %d\n", direntry->d_name,

1638

WEXITSTATUS(status));

1639

free(fullname);

1640

continue;

1641

}

1642

} else if(WIFSIGNALED(status)){

1643

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1644

" signal %d\n", direntry->d_name,

1645

WTERMSIG(status));

1646

free(fullname);

1647

continue;

1648

} else {

1649

fprintf_plus(stderr, "Warning: network hook \"%s\""

1650

" crashed\n", direntry->d_name);

1651

free(fullname);

1652

continue;

1653

}

1654

}

1655

free(fullname);

1656

if(debug){

1657

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1658

direntry->d_name);

1659

}

1660

}

1661

close(devnull);

1662

}

2070

fprintf_plus(stderr, "Warning: network hook \"%s\""

2071

" crashed\n", direntry->d_name);

2072

free(direntry);

2073

continue;

2074

}

2075

}

2076

if(debug){

2077

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

2078

direntry->d_name);

2079

}

2080

free(direntry);

2081

}

2082

free(direntries);

2083

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

2084

perror_plus("close");

2085

} else {

2086

hookdir_fd = -1;

2087

}

2088

close(devnull);

1663

2089

}

1664

2090

1665

2091

__attribute__((nonnull, warn_unused_result))

1666

error_t bring_up_interface(const char *const interface,

1667

const float delay){

1668

error_t old_errno = errno;

2092

int bring_up_interface(const char *const interface,

2093

const float delay){

2094

int old_errno = errno;

1669

2095

int ret;

1670

2096

struct ifreq network;

1671

2097

unsigned int if_index = if_nametoindex(interface);

1681

2107

}

1682

2108

1683

2109

if(not interface_is_up(interface)){

1684

error_t ret_errno = 0, ioctl_errno = 0;

2110

int ret_errno = 0;

2111

int ioctl_errno = 0;

1685

2112

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

1686

2113

ret_errno = errno;

1687

2114

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

1700

2127

}

1701

2128

1702

2129

if(quit_now){

1703

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

2130

ret = close(sd);

1704

2131

if(ret == -1){

1705

2132

perror_plus("close");

1706

2133

}

1716

2143

/* Raise privileges */

1717

2144

ret_errno = raise_privileges();

1718

2145

if(ret_errno != 0){

2146

errno = ret_errno;

1719

2147

perror_plus("Failed to raise privileges");

1720

2148

}

1721

2149

1755

2183

}

1756

2184

1757

2185

/* Close the socket */

1758

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

2186

ret = close(sd);

1759

2187

if(ret == -1){

1760

2188

perror_plus("close");

1761

2189

}

1773

2201

1774

2202

/* Sleep checking until interface is running.

1775

2203

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

1776

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

2204

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

1777

2205

if(interface_is_running(interface)){

1778

2206

break;

1779

2207

}

1789

2217

}

1790

2218

1791

2219

__attribute__((nonnull, warn_unused_result))

1792

error_t take_down_interface(const char *const interface){

1793

error_t old_errno = errno;

2220

int take_down_interface(const char *const interface){

2221

int old_errno = errno;

1794

2222

struct ifreq network;

1795

2223

unsigned int if_index = if_nametoindex(interface);

1796

2224

if(if_index == 0){

1799

2227

return ENXIO;

1800

2228

}

1801

2229

if(interface_is_up(interface)){

1802

error_t ret_errno = 0, ioctl_errno = 0;

2230

int ret_errno = 0;

2231

int ioctl_errno = 0;

1803

2232

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

1804

2233

ret_errno = errno;

1805

2234

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

1825

2254

/* Raise privileges */

1826

2255

ret_errno = raise_privileges();

1827

2256

if(ret_errno != 0){

2257

errno = ret_errno;

1828

2258

perror_plus("Failed to raise privileges");

1829

2259

}

1830

2260

1842

2272

}

1843

2273

1844

2274

/* Close the socket */

1845

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

2275

int ret = close(sd);

1846

2276

if(ret == -1){

1847

2277

perror_plus("close");

1848

2278

}

1863

2293

}

1864

2294

1865

2295

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

1866

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

1867

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

1868

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

1869

.interfaces = NULL, .interfaces_size = 0 };

2296

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

2297

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

2298

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

2299

.current_server = NULL, .interfaces = NULL,

2300

.interfaces_size = 0 };

1870

2301

AvahiSServiceBrowser *sb = NULL;

1871

2302

error_t ret_errno;

1872

2303

int ret;

1881

2312

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1882

2313

const char *seckey = PATHDIR "/" SECKEY;

1883

2314

const char *pubkey = PATHDIR "/" PUBKEY;

2315

const char *dh_params_file = NULL;

1884

2316

char *interfaces_hooks = NULL;

1885

2317

1886

2318

bool gnutls_initialized = false;

1939

2371

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

1940

2372

" Diffie-Hellman key exchange",

1941

2373

.group = 2 },

2374

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

2375

.arg = "FILE",

2376

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

2377

" for the Diffie-Hellman key exchange",

2378

.group = 2 },

1942

2379

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

1943

2380

.arg = "STRING",

1944

2381

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

1999

2436

}

2000

2437

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

2001

2438

break;

2439

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

2440

dh_params_file = arg;

2441

break;

2002

2442

case 130: /* --priority */

2003

2443

mc.priority = arg;

2004

2444

break;

2044

2484

.args_doc = "",

2045

2485

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

2046

2486

" passwords from a Mandos server" };

2047

ret = argp_parse(&argp, argc, argv,

2048

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2049

switch(ret){

2487

ret_errno = argp_parse(&argp, argc, argv,

2488

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2489

switch(ret_errno){

2050

2490

case 0:

2051

2491

break;

2052

2492

case ENOMEM:

2053

2493

default:

2054

errno = ret;

2494

errno = ret_errno;

2055

2495

perror_plus("argp_parse");

2056

2496

exitcode = EX_OSERR;

2057

2497

goto end;

2060

2500

goto end;

2061

2501

}

2062

2502

}

2063

2503

2064

2504

{

2065

2505

/* Work around Debian bug #633582:

2066

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

2506

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

2067

2507

2068

2508

/* Re-raise privileges */

2069

ret_errno = raise_privileges();

2070

if(ret_errno != 0){

2071

errno = ret_errno;

2509

ret = raise_privileges();

2510

if(ret != 0){

2511

errno = ret;

2072

2512

perror_plus("Failed to raise privileges");

2073

2513

} else {

2074

2514

struct stat st;

2090

2530

}

2091

2531

}

2092

2532

}

2093

TEMP_FAILURE_RETRY(close(seckey_fd));

2533

close(seckey_fd);

2094

2534

}

2095

2535

}

2096

2536

2097

2537

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

2098

2538

int pubkey_fd = open(pubkey, O_RDONLY);

2099

2539

if(pubkey_fd == -1){

2111

2551

}

2112

2552

}

2113

2553

}

2114

TEMP_FAILURE_RETRY(close(pubkey_fd));

2115

}

2116

}

2117

2554

close(pubkey_fd);

2555

}

2556

}

2557

2558

if(dh_params_file != NULL

2559

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

2560

int dhparams_fd = open(dh_params_file, O_RDONLY);

2561

if(dhparams_fd == -1){

2562

perror_plus("open");

2563

} else {

2564

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

2565

if(ret == -1){

2566

perror_plus("fstat");

2567

} else {

2568

if(S_ISREG(st.st_mode)

2569

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

2570

ret = fchown(dhparams_fd, uid, gid);

2571

if(ret == -1){

2572

perror_plus("fchown");

2573

}

2574

}

2575

}

2576

close(dhparams_fd);

2577

}

2578

}

2579

2118

2580

/* Lower privileges */

2119

ret_errno = lower_privileges();

2120

if(ret_errno != 0){

2121

errno = ret_errno;

2581

ret = lower_privileges();

2582

if(ret != 0){

2583

errno = ret;

2122

2584

perror_plus("Failed to lower privileges");

2123

2585

}

2124

2586

}

2237

2699

2238

2700

/* If no interfaces were specified, make a list */

2239

2701

if(mc.interfaces == NULL){

2240

struct dirent **direntries;

2702

struct dirent **direntries = NULL;

2241

2703

/* Look for any good interfaces */

2242

2704

ret = scandir(sys_class_net, &direntries, good_interface,

2243

2705

alphasort);

2249

2711

if(ret_errno != 0){

2250

2712

errno = ret_errno;

2251

2713

perror_plus("argz_add");

2714

free(direntries[i]);

2252

2715

continue;

2253

2716

}

2254

2717

if(debug){

2255

2718

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2256

2719

direntries[i]->d_name);

2257

2720

}

2721

free(direntries[i]);

2258

2722

}

2259

2723

free(direntries);

2260

2724

} else {

2261

free(direntries);

2725

if(ret == 0){

2726

free(direntries);

2727

}

2262

2728

fprintf_plus(stderr, "Could not find a network interface\n");

2263

2729

exitcode = EXIT_FAILURE;

2264

2730

goto end;

2290

2756

errno = bring_up_interface(interface, delay);

2291

2757

if(not interface_was_up){

2292

2758

if(errno != 0){

2293

perror_plus("Failed to bring up interface");

2759

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

2760

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

2294

2761

} else {

2295

2762

errno = argz_add(&interfaces_to_take_down,

2296

2763

&interfaces_to_take_down_size,

2319

2786

goto end;

2320

2787

}

2321

2788

2322

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

2789

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

2323

2790

if(ret == -1){

2324

2791

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

2325

2792

exitcode = EX_UNAVAILABLE;

2447

2914

2448

2915

/* Allocate a new server */

2449

2916

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2450

&config, NULL, NULL, &ret_errno);

2917

&config, NULL, NULL, &ret);

2451

2918

2452

2919

/* Free the Avahi configuration data */

2453

2920

avahi_server_config_free(&config);

2456

2923

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

2457

2924

if(mc.server == NULL){

2458

2925

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

2459

avahi_strerror(ret_errno));

2926

avahi_strerror(ret));

2460

2927

exitcode = EX_UNAVAILABLE;

2461

2928

goto end;

2462

2929

}

2486

2953

if(debug){

2487

2954

fprintf_plus(stderr, "Starting Avahi loop search\n");

2488

2955

}

2489

2956

2490

2957

ret = avahi_loop_with_timeout(simple_poll,

2491

2958

(int)(retry_interval * 1000), &mc);

2492

2959

if(debug){

2497

2964

end:

2498

2965

2499

2966

if(debug){

2500

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

2967

if(signal_received){

2968

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

2969

argv[0], signal_received,

2970

strsignal(signal_received));

2971

} else {

2972

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

2973

}

2501

2974

}

2502

2975

2503

2976

/* Cleanup things */

2514

2987

2515

2988

if(gnutls_initialized){

2516

2989

gnutls_certificate_free_credentials(mc.cred);

2517

gnutls_global_deinit();

2518

2990

gnutls_dh_params_deinit(mc.dh_params);

2519

2991

}

2520

2992

2528

3000

mc.current_server->prev->next = NULL;

2529

3001

while(mc.current_server != NULL){

2530

3002

server *next = mc.current_server->next;

3003

#ifdef __GNUC__

3004

#pragma GCC diagnostic push

3005

#pragma GCC diagnostic ignored "-Wcast-qual"

3006

#endif

3007

free((char *)(mc.current_server->ip));

3008

#ifdef __GNUC__

3009

#pragma GCC diagnostic pop

3010

#endif

2531

3011

free(mc.current_server);

2532

3012

mc.current_server = next;

2533

3013

}

2535

3015

2536

3016

/* Re-raise privileges */

2537

3017

{

2538

ret_errno = raise_privileges();

2539

if(ret_errno != 0){

3018

ret = raise_privileges();

3019

if(ret != 0){

3020

errno = ret;

2540

3021

perror_plus("Failed to raise privileges");

2541

3022

} else {

2542

3023

2547

3028

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

2548

3029

{

2549

3030

char *interface = NULL;

2550

while((interface=argz_next(interfaces_to_take_down,

2551

interfaces_to_take_down_size,

2552

interface))){

2553

ret_errno = take_down_interface(interface);

2554

if(ret_errno != 0){

2555

errno = ret_errno;

3031

while((interface = argz_next(interfaces_to_take_down,

3032

interfaces_to_take_down_size,

3033

interface))){

3034

ret = take_down_interface(interface);

3035

if(ret != 0){

3036

errno = ret;

2556

3037

perror_plus("Failed to take down interface");

2557

3038

}

2558

3039

}

2563

3044

}

2564

3045

}

2565

3046

2566

ret_errno = lower_privileges_permanently();

2567

if(ret_errno != 0){

3047

ret = lower_privileges_permanently();

3048

if(ret != 0){

3049

errno = ret;

2568

3050

perror_plus("Failed to lower privileges permanently");

2569

3051

}

2570

3052

}

2572

3054

free(interfaces_to_take_down);

2573

3055

free(interfaces_hooks);

2574

3056

3057

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

3058

uintmax_t level){

3059

struct dirent **direntries = NULL;

3060

int dret;

3061

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

3062

O_RDONLY

3063

| O_NOFOLLOW

3064

| O_DIRECTORY

3065

| O_PATH));

3066

if(dir_fd == -1){

3067

perror_plus("open");

3068

return;

3069

}

3070

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

3071

notdotentries, alphasort);

3072

if(numentries >= 0){

3073

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

3074

if(debug){

3075

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

3076

dirname, direntries[i]->d_name);

3077

}

3078

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

3079

if(dret == -1){

3080

if(errno == EISDIR){

3081

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

3082

AT_REMOVEDIR);

3083

}

3084

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

3085

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

3086

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

3087

/* Recurse only in this special case */

3088

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

3089

dret = 0;

3090

}

3091

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

3092

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

3093

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

3094

}

3095

}

3096

free(direntries[i]);

3097

}

3098

3099

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

3100

free(direntries);

3101

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3102

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

3103

perror_plus("rmdir");

3104

}

3105

} else {

3106

perror_plus("scandirat");

3107

}

3108

close(dir_fd);

3109

}

3110

2575

3111

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

2576

3112

if(tempdir != NULL){

2577

struct dirent **direntries = NULL;

2578

struct dirent *direntry = NULL;

2579

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

2580

alphasort);

2581

if(numentries > 0){

2582

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

2583

direntry = direntries[i];

2584

char *fullname = NULL;

2585

ret = asprintf(&fullname, "%s/%s", tempdir,

2586

direntry->d_name);

2587

if(ret < 0){

2588

perror_plus("asprintf");

2589

continue;

2590

}

2591

ret = remove(fullname);

2592

if(ret == -1){

2593

fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,

2594

strerror(errno));

2595

}

2596

free(fullname);

2597

}

2598

}

2599

2600

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

2601

free(direntries);

2602

if(numentries == -1){

2603

perror_plus("scandir");

2604

}

2605

ret = rmdir(tempdir);

2606

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

2607

perror_plus("rmdir");

2608

}

3113

clean_dir_at(-1, tempdir, 0);

2609

3114

}

2610

3115

2611

3116

if(quit_now){