/mandos/trunk : revision 905

9

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

10

*

11

* Everything else is

12

13

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

41

42

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

43

stdout, ferror(), remove() */

43

stdout, ferror() */

44

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

45

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

46

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

47

strtof(), abort() */

48

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

49

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

50

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

49

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

50

asprintf(), strncpy(), strsignal()

51

*/

51

52

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

52

53

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

53

54

sockaddr_in6, PF_INET6,

57

58

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

58

59

inet_pton(), connect(),

59

60

getnameinfo() */

60

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

61

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

61

62

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

62

63

*/

63

64

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

64

65

strtoimax() */

65

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

66

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

67

EAI_SYSTEM, ENETUNREACH,

68

EHOSTUNREACH, ECONNREFUSED, EPROTO,

69

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

70

ENOTEMPTY,

66

71

program_invocation_short_name */

67

72

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

68

73

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

73

78

*/

74

79

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

75

80

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

76

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

81

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

82

unlinkat() */

77

83

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

78

84

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

79

85

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

136

142

137

143

bool debug = false;

138

144

static const char mandos_protocol_version[] = "1";

139

const char * argp_program_version = "mandos-client " VERSION;

140

const char * argp_program_bug_address = "<mandos@recompile.se>";

145

const char *argp_program_version = "mandos-client " VERSION;

146

const char *argp_program_bug_address = "<mandos@recompile.se>";

141

147

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

142

148

char *connect_to = NULL;

143

149

const char *hookdir = HOOKDIR;

150

int hookdir_fd = -1;

144

151

uid_t uid = 65534;

145

152

gid_t gid = 65534;

146

153

232

239

.af = af };

233

240

if(new_server->ip == NULL){

234

241

perror_plus("strdup");

242

free(new_server);

235

243

return false;

236

244

}

237

245

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

238

246

if(ret == -1){

239

247

perror_plus("clock_gettime");

248

#ifdef __GNUC__

249

#pragma GCC diagnostic push

250

#pragma GCC diagnostic ignored "-Wcast-qual"

251

#endif

252

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

253

#ifdef __GNUC__

254

#pragma GCC diagnostic pop

255

#endif

256

free(new_server);

240

257

return false;

241

258

}

242

259

/* Special case of first server */

293

310

return false;

294

311

}

295

312

296

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

313

ret = close(fd);

297

314

if(ret == -1){

298

315

perror_plus("close");

299

316

}

481

498

return plaintext_length;

482

499

}

483

500

501

__attribute__((warn_unused_result, const))

502

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

503

if(str == NULL)

504

return "(unknown)";

505

return str;

506

}

507

484

508

__attribute__((warn_unused_result))

485

509

static const char *safer_gnutls_strerror(int value){

486

510

const char *ret = gnutls_strerror(value);

487

if(ret == NULL)

488

ret = "(unknown)";

489

return ret;

511

return safe_string(ret);

490

512

}

491

513

492

514

/* GnuTLS log function callback */

496

518

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

497

519

}

498

520

499

__attribute__((nonnull, warn_unused_result))

521

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

500

522

static int init_gnutls_global(const char *pubkeyfilename,

501

523

const char *seckeyfilename,

524

const char *dhparamsfilename,

502

525

mandos_context *mc){

503

526

int ret;

527

unsigned int uret;

504

528

505

529

if(debug){

506

530

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

507

531

}

508

532

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

533

if(debug){

517

534

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

518

535

* - GnuTLS manual

526

543

if(ret != GNUTLS_E_SUCCESS){

527

544

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

528

545

safer_gnutls_strerror(ret));

529

gnutls_global_deinit();

530

546

return -1;

531

547

}

532

548

557

573

safer_gnutls_strerror(ret));

558

574

goto globalfail;

559

575

}

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

576

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

577

if(dhparamsfilename != NULL){

578

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

579

do {

580

int dhpfile = open(dhparamsfilename, O_RDONLY);

581

if(dhpfile == -1){

582

perror_plus("open");

583

dhparamsfilename = NULL;

584

break;

585

}

586

size_t params_capacity = 0;

587

while(true){

588

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

589

(size_t)params.size,

590

(size_t)params_capacity);

591

if(params_capacity == 0){

592

perror_plus("incbuffer");

593

free(params.data);

594

params.data = NULL;

595

dhparamsfilename = NULL;

596

break;

597

}

598

ssize_t bytes_read = read(dhpfile,

599

params.data + params.size,

600

BUFFER_SIZE);

601

/* EOF */

602

if(bytes_read == 0){

603

break;

604

}

605

/* check bytes_read for failure */

606

if(bytes_read < 0){

607

perror_plus("read");

608

free(params.data);

609

params.data = NULL;

610

dhparamsfilename = NULL;

611

break;

612

}

613

params.size += (unsigned int)bytes_read;

614

}

615

if(params.data == NULL){

616

dhparamsfilename = NULL;

617

}

618

if(dhparamsfilename == NULL){

619

break;

620

}

621

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

622

GNUTLS_X509_FMT_PEM);

623

if(ret != GNUTLS_E_SUCCESS){

624

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

625

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

626

safer_gnutls_strerror(ret));

627

dhparamsfilename = NULL;

628

}

629

free(params.data);

630

} while(false);

631

}

632

if(dhparamsfilename == NULL){

633

if(mc->dh_bits == 0){

634

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

635

/* Try to read the private key file */

636

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

637

do {

638

int secfile = open(seckeyfilename, O_RDONLY);

639

if(secfile == -1){

640

perror_plus("open");

641

break;

642

}

643

size_t buffer_capacity = 0;

644

while(true){

645

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

646

(size_t)buffer.size,

647

(size_t)buffer_capacity);

648

if(buffer_capacity == 0){

649

perror_plus("incbuffer");

650

free(buffer.data);

651

buffer.data = NULL;

652

break;

653

}

654

ssize_t bytes_read = read(secfile,

655

buffer.data + buffer.size,

656

BUFFER_SIZE);

657

/* EOF */

658

if(bytes_read == 0){

659

break;

660

}

661

/* check bytes_read for failure */

662

if(bytes_read < 0){

663

perror_plus("read");

664

free(buffer.data);

665

buffer.data = NULL;

666

break;

667

}

668

buffer.size += (unsigned int)bytes_read;

669

}

670

close(secfile);

671

} while(false);

672

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

673

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

674

if(buffer.data != NULL){

675

{

676

gnutls_openpgp_privkey_t privkey = NULL;

677

ret = gnutls_openpgp_privkey_init(&privkey);

678

if(ret != GNUTLS_E_SUCCESS){

679

fprintf_plus(stderr, "Error initializing OpenPGP key"

680

" structure: %s",

681

safer_gnutls_strerror(ret));

682

free(buffer.data);

683

buffer.data = NULL;

684

} else {

685

ret = gnutls_openpgp_privkey_import

686

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

687

if(ret != GNUTLS_E_SUCCESS){

688

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

689

safer_gnutls_strerror(ret));

690

privkey = NULL;

691

}

692

free(buffer.data);

693

buffer.data = NULL;

694

if(privkey != NULL){

695

/* Use private key to suggest an appropriate

696

sec_param */

697

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

698

gnutls_openpgp_privkey_deinit(privkey);

699

if(debug){

700

fprintf_plus(stderr, "This OpenPGP key implies using"

701

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

702

safe_string(gnutls_sec_param_get_name

703

(sec_param)));

704

}

705

}

706

}

707

}

708

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

709

/* Err on the side of caution */

710

sec_param = GNUTLS_SEC_PARAM_ULTRA;

711

if(debug){

712

fprintf_plus(stderr, "Falling back to security parameter"

713

" \"%s\"\n",

714

safe_string(gnutls_sec_param_get_name

715

(sec_param)));

716

}

717

}

718

}

719

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

720

if(uret != 0){

721

mc->dh_bits = uret;

722

if(debug){

723

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

724

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

725

safe_string(gnutls_sec_param_get_name

726

(sec_param)),

727

mc->dh_bits);

728

}

729

} else {

730

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

731

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

732

safe_string(gnutls_sec_param_get_name

733

(sec_param)),

734

safer_gnutls_strerror(ret));

735

goto globalfail;

736

}

737

} else if(debug){

738

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

739

mc->dh_bits);

740

}

741

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

742

if(ret != GNUTLS_E_SUCCESS){

743

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

744

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

745

safer_gnutls_strerror(ret));

746

goto globalfail;

747

}

748

}

567

749

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

568

750

569

751

return 0;

571

753

globalfail:

572

754

573

755

gnutls_certificate_free_credentials(mc->cred);

574

gnutls_global_deinit();

575

756

gnutls_dh_params_deinit(mc->dh_params);

576

757

return -1;

577

758

}

629

810

/* ignore client certificate if any. */

630

811

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

631

812

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

633

634

813

return 0;

635

814

}

636

815

638

817

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

639

818

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

640

819

820

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

821

__attribute__((warn_unused_result))

822

int raise_privileges(void){

823

int old_errno = errno;

824

int ret = 0;

825

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

826

ret = errno;

827

}

828

errno = old_errno;

829

return ret;

830

}

831

832

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

833

__attribute__((warn_unused_result))

834

int raise_privileges_permanently(void){

835

int old_errno = errno;

836

int ret = raise_privileges();

837

if(ret != 0){

838

errno = old_errno;

839

return ret;

840

}

841

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

842

ret = errno;

843

}

844

errno = old_errno;

845

return ret;

846

}

847

848

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

849

__attribute__((warn_unused_result))

850

int lower_privileges(void){

851

int old_errno = errno;

852

int ret = 0;

853

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

854

ret = errno;

855

}

856

errno = old_errno;

857

return ret;

858

}

859

860

/* Lower privileges permanently */

861

__attribute__((warn_unused_result))

862

int lower_privileges_permanently(void){

863

int old_errno = errno;

864

int ret = 0;

865

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

866

ret = errno;

867

}

868

errno = old_errno;

869

return ret;

870

}

871

872

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

873

__attribute__((nonnull, warn_unused_result))

874

static bool add_delete_local_route(const bool add,

875

const char *address,

876

AvahiIfIndex if_index){

877

int ret;

878

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

879

char add_arg[] = "add";

880

char delete_arg[] = "delete";

881

char debug_flag[] = "--debug";

882

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

883

if(pluginhelperdir == NULL){

884

if(debug){

885

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

886

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

887

}

888

return false;

889

}

890

891

char interface[IF_NAMESIZE];

892

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

893

perror_plus("if_indextoname");

894

return false;

895

}

896

897

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

898

if(devnull == -1){

899

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

900

return false;

901

}

902

pid_t pid = fork();

903

if(pid == 0){

904

/* Child */

905

/* Raise privileges */

906

errno = raise_privileges_permanently();

907

if(errno != 0){

908

perror_plus("Failed to raise privileges");

909

/* _exit(EX_NOPERM); */

910

} else {

911

/* Set group */

912

errno = 0;

913

ret = setgid(0);

914

if(ret == -1){

915

perror_plus("setgid");

916

_exit(EX_NOPERM);

917

}

918

/* Reset supplementary groups */

919

errno = 0;

920

ret = setgroups(0, NULL);

921

if(ret == -1){

922

perror_plus("setgroups");

923

_exit(EX_NOPERM);

924

}

925

}

926

ret = dup2(devnull, STDIN_FILENO);

927

if(ret == -1){

928

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

929

_exit(EX_OSERR);

930

}

931

ret = close(devnull);

932

if(ret == -1){

933

perror_plus("close");

934

_exit(EX_OSERR);

935

}

936

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

937

if(ret == -1){

938

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

939

_exit(EX_OSERR);

940

}

941

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

942

O_RDONLY

943

| O_DIRECTORY

944

| O_PATH

945

| O_CLOEXEC));

946

if(helperdir_fd == -1){

947

perror_plus("open");

948

_exit(EX_UNAVAILABLE);

949

}

950

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

951

helper, O_RDONLY));

952

if(helper_fd == -1){

953

perror_plus("openat");

954

close(helperdir_fd);

955

_exit(EX_UNAVAILABLE);

956

}

957

close(helperdir_fd);

958

#ifdef __GNUC__

959

#pragma GCC diagnostic push

960

#pragma GCC diagnostic ignored "-Wcast-qual"

961

#endif

962

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

963

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

964

interface, debug ? debug_flag : NULL, NULL },

965

environ) == -1){

966

#ifdef __GNUC__

967

#pragma GCC diagnostic pop

968

#endif

969

perror_plus("fexecve");

970

_exit(EXIT_FAILURE);

971

}

972

}

973

if(pid == -1){

974

perror_plus("fork");

975

return false;

976

}

977

int status;

978

pid_t pret = -1;

979

errno = 0;

980

do {

981

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

982

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

983

int errno_raising = 0;

984

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

985

errno_raising = errno;

986

perror_plus("Failed to raise privileges in order to"

987

" kill helper program");

988

}

989

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

990

perror_plus("kill");

991

}

992

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

993

perror_plus("Failed to lower privileges after killing"

994

" helper program");

995

}

996

return false;

997

}

998

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

999

if(pret == -1){

1000

perror_plus("waitpid");

1001

return false;

1002

}

1003

if(WIFEXITED(status)){

1004

if(WEXITSTATUS(status) != 0){

1005

fprintf_plus(stderr, "Error: iprouteadddel exited"

1006

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

1007

return false;

1008

}

1009

return true;

1010

}

1011

if(WIFSIGNALED(status)){

1012

fprintf_plus(stderr, "Error: iprouteadddel died by"

1013

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

1014

return false;

1015

}

1016

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

1017

return false;

1018

}

1019

1020

__attribute__((nonnull, warn_unused_result))

1021

static bool add_local_route(const char *address,

1022

AvahiIfIndex if_index){

1023

if(debug){

1024

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

1025

}

1026

return add_delete_local_route(true, address, if_index);

1027

}

1028

1029

__attribute__((nonnull, warn_unused_result))

1030

static bool delete_local_route(const char *address,

1031

AvahiIfIndex if_index){

1032

if(debug){

1033

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

1034

}

1035

return add_delete_local_route(false, address, if_index);

1036

}

1037

641

1038

/* Called when a Mandos server is found */

642

1039

__attribute__((nonnull, warn_unused_result))

643

1040

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

654

1051

int retval = -1;

655

1052

gnutls_session_t session;

656

1053

int pf; /* Protocol family */

1054

bool route_added = false;

657

1055

658

1056

errno = 0;

659

1057

681

1079

bool match = false;

682

1080

{

683

1081

char *interface = NULL;

684

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

685

interface))){

1082

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

1083

mc->interfaces_size,

1084

interface))){

686

1085

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

687

1086

match = true;

688

1087

break;

717

1116

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

718

1117

}

719

1118

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

1119

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

721

1120

if(tcp_sd < 0){

722

1121

int e = errno;

723

1122

perror_plus("socket");

730

1129

goto mandos_end;

731

1130

}

732

1131

733

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

734

1132

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);

1133

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

1134

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

1135

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

737

1136

} 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);

1137

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

1138

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

1139

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

740

1140

}

741

1141

if(ret < 0 ){

742

1142

int e = errno;

812

1212

goto mandos_end;

813

1213

}

814

1214

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;

1215

while(true){

1216

if(af == AF_INET6){

1217

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

1218

sizeof(struct sockaddr_in6));

1219

} else {

1220

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

1221

sizeof(struct sockaddr_in));

1222

}

1223

if(ret < 0){

1224

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

1225

and if_index != AVAHI_IF_UNSPEC

1226

and connect_to == NULL

1227

and not route_added and

1228

((af == AF_INET6 and not

1229

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1230

&to)->sin6_addr)))

1231

or (af == AF_INET and

1232

/* Not a a IPv4LL address */

1233

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

1234

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

1235

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

1236

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

1237

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

1238

connect to a Mandos server announced by Avahi on a server

1239

host with a global address. Work around this by retrying

1240

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

1241

1242

Avahi bug reference:

1243

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

1244

https://bugs.debian.org/587961

1245

*/

1246

if(debug){

1247

fprintf_plus(stderr, "Mandos server unreachable, trying"

1248

" direct route\n");

1249

}

1250

int e = errno;

1251

route_added = add_local_route(ip, if_index);

1252

if(route_added){

1253

continue;

1254

}

1255

errno = e;

1256

}

1257

if(errno != ECONNREFUSED or debug){

1258

int e = errno;

1259

perror_plus("connect");

1260

errno = e;

1261

}

1262

goto mandos_end;

1263

}

1264

1265

if(quit_now){

1266

errno = EINTR;

1267

goto mandos_end;

1268

}

1269

break;

834

1270

}

835

1271

836

1272

const char *out = mandos_protocol_version;

990

1426

&decrypted_buffer, mc);

991

1427

if(decrypted_buffer_size >= 0){

992

1428

1429

clearerr(stdout);

993

1430

written = 0;

994

1431

while(written < (size_t) decrypted_buffer_size){

995

1432

if(quit_now){

1011

1448

}

1012

1449

written += (size_t)ret;

1013

1450

}

1451

ret = fflush(stdout);

1452

if(ret != 0){

1453

int e = errno;

1454

if(debug){

1455

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

1456

strerror(errno));

1457

}

1458

errno = e;

1459

goto mandos_end;

1460

}

1014

1461

retval = 0;

1015

1462

}

1016

1463

}

1019

1466

1020

1467

mandos_end:

1021

1468

{

1469

if(route_added){

1470

if(not delete_local_route(ip, if_index)){

1471

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

1472

" interface %d", ip, if_index);

1473

}

1474

}

1022

1475

int e = errno;

1023

1476

free(decrypted_buffer);

1024

1477

free(buffer);

1025

1478

if(tcp_sd >= 0){

1026

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

1479

ret = close(tcp_sd);

1027

1480

}

1028

1481

if(ret == -1){

1029

1482

if(e == 0){

1041

1494

return retval;

1042

1495

}

1043

1496

1044

__attribute__((nonnull))

1045

1497

static void resolve_callback(AvahiSServiceResolver *r,

1046

1498

AvahiIfIndex interface,

1047

1499

AvahiProtocol proto,

1064

1516

timed out */

1065

1517

1066

1518

if(quit_now){

1519

avahi_s_service_resolver_free(r);

1067

1520

return;

1068

1521

}

1069

1522

1183

1636

__attribute__((nonnull, warn_unused_result))

1184

1637

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

1185

1638

int ret;

1186

error_t ret_errno;

1639

int old_errno;

1187

1640

1188

1641

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

1189

1642

if(s < 0){

1190

ret_errno = errno;

1643

old_errno = errno;

1191

1644

perror_plus("socket");

1192

errno = ret_errno;

1645

errno = old_errno;

1193

1646

return false;

1194

1647

}

1195

strcpy(ifr->ifr_name, ifname);

1648

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

1649

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

1196

1650

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1197

1651

if(ret == -1){

1198

1652

if(debug){

1199

ret_errno = errno;

1653

old_errno = errno;

1200

1654

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1655

errno = old_errno;

1202

1656

}

1203

1657

return false;

1204

1658

}

1335

1789

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

1336

1790

"abcdefghijklmnopqrstuvwxyz"

1337

1791

"0123456789"

1338

"_-");

1792

"_.-");

1339

1793

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

1340

1794

/* Contains non-allowed characters */

1341

1795

if(debug){

1345

1799

return 0;

1346

1800

}

1347

1801

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);

1802

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

1356

1803

if(ret == -1){

1357

1804

if(debug){

1358

1805

perror_plus("Could not stat hook");

1456

1903

}

1457

1904

}

1458

1905

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

1906

__attribute__((nonnull))

1516

1907

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

1517

1908

const float delay){

1518

struct dirent **direntries;

1519

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

1520

alphasort);

1909

struct dirent **direntries = NULL;

1910

if(hookdir_fd == -1){

1911

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1912

| O_CLOEXEC);

1913

if(hookdir_fd == -1){

1914

if(errno == ENOENT){

1915

if(debug){

1916

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

1917

" found\n", hookdir);

1918

}

1919

} else {

1920

perror_plus("open");

1921

}

1922

return;

1923

}

1924

}

1925

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

1926

runnable_hook, alphasort);

1521

1927

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");

1928

perror_plus("scandir");

1929

return;

1930

}

1931

struct dirent *direntry;

1932

int ret;

1933

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

1934

if(devnull == -1){

1935

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

1936

return;

1937

}

1938

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

1939

direntry = direntries[i];

1940

if(debug){

1941

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

1942

direntry->d_name);

1529

1943

}

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){

1944

pid_t hook_pid = fork();

1945

if(hook_pid == 0){

1946

/* Child */

1947

/* Raise privileges */

1948

errno = raise_privileges_permanently();

1949

if(errno != 0){

1950

perror_plus("Failed to raise privileges");

1951

_exit(EX_NOPERM);

1952

}

1953

/* Set group */

1954

errno = 0;

1955

ret = setgid(0);

1956

if(ret == -1){

1957

perror_plus("setgid");

1958

_exit(EX_NOPERM);

1959

}

1960

/* Reset supplementary groups */

1961

errno = 0;

1962

ret = setgroups(0, NULL);

1963

if(ret == -1){

1964

perror_plus("setgroups");

1965

_exit(EX_NOPERM);

1966

}

1967

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

1968

if(ret == -1){

1969

perror_plus("setenv");

1970

_exit(EX_OSERR);

1971

}

1972

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

1973

if(ret == -1){

1974

perror_plus("setenv");

1975

_exit(EX_OSERR);

1976

}

1977

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

1978

if(ret == -1){

1979

perror_plus("setenv");

1980

_exit(EX_OSERR);

1981

}

1982

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

1983

if(ret == -1){

1984

perror_plus("setenv");

1985

_exit(EX_OSERR);

1986

}

1987

char *delaystring;

1988

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

1989

if(ret == -1){

1539

1990

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

}

1991

_exit(EX_OSERR);

1992

}

1993

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

1994

if(ret == -1){

1615

1995

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

}

1996

perror_plus("setenv");

1997

_exit(EX_OSERR);

1998

}

1999

free(delaystring);

2000

if(connect_to != NULL){

2001

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

2002

if(ret == -1){

2003

perror_plus("setenv");

2004

_exit(EX_OSERR);

2005

}

2006

}

2007

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

2008

direntry->d_name,

2009

O_RDONLY));

2010

if(hook_fd == -1){

2011

perror_plus("openat");

2012

_exit(EXIT_FAILURE);

2013

}

2014

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

2015

perror_plus("close");

2016

_exit(EXIT_FAILURE);

2017

}

2018

ret = dup2(devnull, STDIN_FILENO);

2019

if(ret == -1){

2020

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

2021

_exit(EX_OSERR);

2022

}

2023

ret = close(devnull);

2024

if(ret == -1){

2025

perror_plus("close");

2026

_exit(EX_OSERR);

2027

}

2028

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2029

if(ret == -1){

2030

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

2031

_exit(EX_OSERR);

2032

}

2033

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

2034

environ) == -1){

2035

perror_plus("fexecve");

2036

_exit(EXIT_FAILURE);

2037

}

2038

} else {

2039

if(hook_pid == -1){

2040

perror_plus("fork");

2041

free(direntry);

2042

continue;

2043

}

2044

int status;

2045

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

2046

perror_plus("waitpid");

2047

free(direntry);

2048

continue;

2049

}

2050

if(WIFEXITED(status)){

2051

if(WEXITSTATUS(status) != 0){

2052

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

2053

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

2054

WEXITSTATUS(status));

2055

free(direntry);

2056

continue;

2057

}

2058

} else if(WIFSIGNALED(status)){

2059

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

2060

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

2061

WTERMSIG(status));

2062

free(direntry);

2063

continue;

1627

2064

} 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

}

2065

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

2066

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

2067

free(direntry);

2068

continue;

2069

}

2070

}

2071

if(debug){

2072

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

2073

direntry->d_name);

2074

}

2075

free(direntry);

2076

}

2077

free(direntries);

2078

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

2079

perror_plus("close");

2080

} else {

2081

hookdir_fd = -1;

2082

}

2083

close(devnull);

1663

2084

}

1664

2085

1665

2086

__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;

2087

int bring_up_interface(const char *const interface,

2088

const float delay){

2089

int old_errno = errno;

1669

2090

int ret;

1670

2091

struct ifreq network;

1671

2092

unsigned int if_index = if_nametoindex(interface);

1681

2102

}

1682

2103

1683

2104

if(not interface_is_up(interface)){

1684

error_t ret_errno = 0, ioctl_errno = 0;

2105

int ret_errno = 0;

2106

int ioctl_errno = 0;

1685

2107

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

1686

2108

ret_errno = errno;

1687

2109

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

1700

2122

}

1701

2123

1702

2124

if(quit_now){

1703

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

2125

ret = close(sd);

1704

2126

if(ret == -1){

1705

2127

perror_plus("close");

1706

2128

}

1715

2137

1716

2138

/* Raise privileges */

1717

2139

ret_errno = raise_privileges();

2140

if(ret_errno != 0){

2141

errno = ret_errno;

2142

perror_plus("Failed to raise privileges");

2143

}

2144

2145

#ifdef __linux__

2146

int ret_linux;

1718

2147

bool restore_loglevel = false;

1719

if(ret_errno != 0){

1720

perror_plus("Failed to raise privileges");

1721

}

1722

#ifdef __linux__

1723

int ret_linux;

1724

2148

if(ret_errno == 0){

1725

2149

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1726

2150

messages about the network interface to mess up the prompt */

1754

2178

}

1755

2179

1756

2180

/* Close the socket */

1757

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

2181

ret = close(sd);

1758

2182

if(ret == -1){

1759

2183

perror_plus("close");

1760

2184

}

1772

2196

1773

2197

/* Sleep checking until interface is running.

1774

2198

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

1775

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

2199

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

1776

2200

if(interface_is_running(interface)){

1777

2201

break;

1778

2202

}

1788

2212

}

1789

2213

1790

2214

__attribute__((nonnull, warn_unused_result))

1791

error_t take_down_interface(const char *const interface){

1792

error_t old_errno = errno;

2215

int take_down_interface(const char *const interface){

2216

int old_errno = errno;

1793

2217

struct ifreq network;

1794

2218

unsigned int if_index = if_nametoindex(interface);

1795

2219

if(if_index == 0){

1798

2222

return ENXIO;

1799

2223

}

1800

2224

if(interface_is_up(interface)){

1801

error_t ret_errno = 0, ioctl_errno = 0;

2225

int ret_errno = 0;

2226

int ioctl_errno = 0;

1802

2227

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

1803

2228

ret_errno = errno;

1804

2229

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

1824

2249

/* Raise privileges */

1825

2250

ret_errno = raise_privileges();

1826

2251

if(ret_errno != 0){

2252

errno = ret_errno;

1827

2253

perror_plus("Failed to raise privileges");

1828

2254

}

2255

1829

2256

int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);

1830

2257

ioctl_errno = errno;

1831

2258

1840

2267

}

1841

2268

1842

2269

/* Close the socket */

1843

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

2270

int ret = close(sd);

1844

2271

if(ret == -1){

1845

2272

perror_plus("close");

1846

2273

}

1861

2288

}

1862

2289

1863

2290

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

1864

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

1865

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

1866

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

1867

.interfaces = NULL, .interfaces_size = 0 };

2291

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

2292

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

2293

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

2294

.current_server = NULL, .interfaces = NULL,

2295

.interfaces_size = 0 };

1868

2296

AvahiSServiceBrowser *sb = NULL;

1869

2297

error_t ret_errno;

1870

2298

int ret;

1879

2307

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1880

2308

const char *seckey = PATHDIR "/" SECKEY;

1881

2309

const char *pubkey = PATHDIR "/" PUBKEY;

2310

const char *dh_params_file = NULL;

1882

2311

char *interfaces_hooks = NULL;

1883

2312

1884

2313

bool gnutls_initialized = false;

1937

2366

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

1938

2367

" Diffie-Hellman key exchange",

1939

2368

.group = 2 },

2369

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

2370

.arg = "FILE",

2371

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

2372

" for the Diffie-Hellman key exchange",

2373

.group = 2 },

1940

2374

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

1941

2375

.arg = "STRING",

1942

2376

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

1997

2431

}

1998

2432

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

1999

2433

break;

2434

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

2435

dh_params_file = arg;

2436

break;

2000

2437

case 130: /* --priority */

2001

2438

mc.priority = arg;

2002

2439

break;

2042

2479

.args_doc = "",

2043

2480

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

2044

2481

" passwords from a Mandos server" };

2045

ret = argp_parse(&argp, argc, argv,

2046

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2047

switch(ret){

2482

ret_errno = argp_parse(&argp, argc, argv,

2483

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2484

switch(ret_errno){

2048

2485

case 0:

2049

2486

break;

2050

2487

case ENOMEM:

2051

2488

default:

2052

errno = ret;

2489

errno = ret_errno;

2053

2490

perror_plus("argp_parse");

2054

2491

exitcode = EX_OSERR;

2055

2492

goto end;

2058

2495

goto end;

2059

2496

}

2060

2497

}

2061

2498

2062

2499

{

2063

2500

/* Work around Debian bug #633582:

2064

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

2501

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

2065

2502

2066

2503

/* Re-raise privileges */

2067

ret_errno = raise_privileges();

2068

if(ret_errno != 0){

2069

errno = ret_errno;

2504

ret = raise_privileges();

2505

if(ret != 0){

2506

errno = ret;

2070

2507

perror_plus("Failed to raise privileges");

2071

2508

} else {

2072

2509

struct stat st;

2088

2525

}

2089

2526

}

2090

2527

}

2091

TEMP_FAILURE_RETRY(close(seckey_fd));

2528

close(seckey_fd);

2092

2529

}

2093

2530

}

2094

2531

2095

2532

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

2096

2533

int pubkey_fd = open(pubkey, O_RDONLY);

2097

2534

if(pubkey_fd == -1){

2109

2546

}

2110

2547

}

2111

2548

}

2112

TEMP_FAILURE_RETRY(close(pubkey_fd));

2113

}

2114

}

2115

2549

close(pubkey_fd);

2550

}

2551

}

2552

2553

if(dh_params_file != NULL

2554

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

2555

int dhparams_fd = open(dh_params_file, O_RDONLY);

2556

if(dhparams_fd == -1){

2557

perror_plus("open");

2558

} else {

2559

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

2560

if(ret == -1){

2561

perror_plus("fstat");

2562

} else {

2563

if(S_ISREG(st.st_mode)

2564

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

2565

ret = fchown(dhparams_fd, uid, gid);

2566

if(ret == -1){

2567

perror_plus("fchown");

2568

}

2569

}

2570

}

2571

close(dhparams_fd);

2572

}

2573

}

2574

2116

2575

/* Lower privileges */

2117

ret_errno = lower_privileges();

2118

if(ret_errno != 0){

2119

errno = ret_errno;

2576

ret = lower_privileges();

2577

if(ret != 0){

2578

errno = ret;

2120

2579

perror_plus("Failed to lower privileges");

2121

2580

}

2122

2581

}

2235

2694

2236

2695

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

2237

2696

if(mc.interfaces == NULL){

2238

struct dirent **direntries;

2697

struct dirent **direntries = NULL;

2239

2698

/* Look for any good interfaces */

2240

2699

ret = scandir(sys_class_net, &direntries, good_interface,

2241

2700

alphasort);

2247

2706

if(ret_errno != 0){

2248

2707

errno = ret_errno;

2249

2708

perror_plus("argz_add");

2709

free(direntries[i]);

2250

2710

continue;

2251

2711

}

2252

2712

if(debug){

2253

2713

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

2254

2714

direntries[i]->d_name);

2255

2715

}

2716

free(direntries[i]);

2256

2717

}

2257

2718

free(direntries);

2258

2719

} else {

2259

free(direntries);

2720

if(ret == 0){

2721

free(direntries);

2722

}

2260

2723

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

2261

2724

exitcode = EXIT_FAILURE;

2262

2725

goto end;

2288

2751

errno = bring_up_interface(interface, delay);

2289

2752

if(not interface_was_up){

2290

2753

if(errno != 0){

2291

perror_plus("Failed to bring up interface");

2754

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

2755

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

2292

2756

} else {

2293

2757

errno = argz_add(&interfaces_to_take_down,

2294

2758

&interfaces_to_take_down_size,

2317

2781

goto end;

2318

2782

}

2319

2783

2320

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

2784

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

2321

2785

if(ret == -1){

2322

2786

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

2323

2787

exitcode = EX_UNAVAILABLE;

2445

2909

2446

2910

/* Allocate a new server */

2447

2911

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2448

&config, NULL, NULL, &ret_errno);

2912

&config, NULL, NULL, &ret);

2449

2913

2450

2914

/* Free the Avahi configuration data */

2451

2915

avahi_server_config_free(&config);

2454

2918

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

2455

2919

if(mc.server == NULL){

2456

2920

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

2457

avahi_strerror(ret_errno));

2921

avahi_strerror(ret));

2458

2922

exitcode = EX_UNAVAILABLE;

2459

2923

goto end;

2460

2924

}

2484

2948

if(debug){

2485

2949

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

2486

2950

}

2487

2951

2488

2952

ret = avahi_loop_with_timeout(simple_poll,

2489

2953

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

2490

2954

if(debug){

2495

2959

end:

2496

2960

2497

2961

if(debug){

2498

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

2962

if(signal_received){

2963

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

2964

argv[0], signal_received,

2965

strsignal(signal_received));

2966

} else {

2967

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

2968

}

2499

2969

}

2500

2970

2501

2971

/* Cleanup things */

2512

2982

2513

2983

if(gnutls_initialized){

2514

2984

gnutls_certificate_free_credentials(mc.cred);

2515

gnutls_global_deinit();

2516

2985

gnutls_dh_params_deinit(mc.dh_params);

2517

2986

}

2518

2987

2526

2995

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

2527

2996

while(mc.current_server != NULL){

2528

2997

server *next = mc.current_server->next;

2998

#ifdef __GNUC__

2999

#pragma GCC diagnostic push

3000

#pragma GCC diagnostic ignored "-Wcast-qual"

3001

#endif

3002

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

3003

#ifdef __GNUC__

3004

#pragma GCC diagnostic pop

3005

#endif

2529

3006

free(mc.current_server);

2530

3007

mc.current_server = next;

2531

3008

}

2533

3010

2534

3011

/* Re-raise privileges */

2535

3012

{

2536

ret_errno = raise_privileges();

2537

if(ret_errno != 0){

3013

ret = raise_privileges();

3014

if(ret != 0){

3015

errno = ret;

2538

3016

perror_plus("Failed to raise privileges");

2539

3017

} else {

2540

3018

2545

3023

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

2546

3024

{

2547

3025

char *interface = NULL;

2548

while((interface=argz_next(interfaces_to_take_down,

2549

interfaces_to_take_down_size,

2550

interface))){

2551

ret_errno = take_down_interface(interface);

2552

if(ret_errno != 0){

2553

errno = ret_errno;

3026

while((interface = argz_next(interfaces_to_take_down,

3027

interfaces_to_take_down_size,

3028

interface))){

3029

ret = take_down_interface(interface);

3030

if(ret != 0){

3031

errno = ret;

2554

3032

perror_plus("Failed to take down interface");

2555

3033

}

2556

3034

}

2560

3038

}

2561

3039

}

2562

3040

}

2563

ret_errno = lower_privileges_permanently();

2564

if(ret_errno != 0){

3041

3042

ret = lower_privileges_permanently();

3043

if(ret != 0){

3044

errno = ret;

2565

3045

perror_plus("Failed to lower privileges permanently");

2566

3046

}

2567

3047

}

2569

3049

free(interfaces_to_take_down);

2570

3050

free(interfaces_hooks);

2571

3051

3052

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

3053

uintmax_t level){

3054

struct dirent **direntries = NULL;

3055

int dret;

3056

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

3057

O_RDONLY

3058

| O_NOFOLLOW

3059

| O_DIRECTORY

3060

| O_PATH));

3061

if(dir_fd == -1){

3062

perror_plus("open");

3063

}

3064

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

3065

notdotentries, alphasort);

3066

if(numentries >= 0){

3067

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

3068

if(debug){

3069

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

3070

dirname, direntries[i]->d_name);

3071

}

3072

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

3073

if(dret == -1){

3074

if(errno == EISDIR){

3075

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

3076

AT_REMOVEDIR);

3077

}

3078

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

3079

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

3080

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

3081

/* Recurse only in this special case */

3082

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

3083

dret = 0;

3084

}

3085

if(dret == -1){

3086

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

3087

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

3088

}

3089

}

3090

free(direntries[i]);

3091

}

3092

3093

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

3094

free(direntries);

3095

if(numentries == -1){

3096

perror_plus("scandirat");

3097

}

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

2572

3108

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

2573

3109

if(tempdir != NULL){

2574

struct dirent **direntries = NULL;

2575

struct dirent *direntry = NULL;

2576

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

2577

alphasort);

2578

if(numentries > 0){

2579

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

2580

direntry = direntries[i];

2581

char *fullname = NULL;

2582

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

2583

direntry->d_name);

2584

if(ret < 0){

2585

perror_plus("asprintf");

2586

continue;

2587

}

2588

ret = remove(fullname);

2589

if(ret == -1){

2590

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

2591

strerror(errno));

2592

}

2593

free(fullname);

2594

}

2595

}

2596

2597

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

2598

free(direntries);

2599

if(numentries == -1){

2600

perror_plus("scandir");

2601

}

2602

ret = rmdir(tempdir);

2603

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

2604

perror_plus("rmdir");

2605

}

3110

clean_dir_at(-1, tempdir, 0);

2606

3111

}

2607

3112

2608

3113

if(quit_now){