/mandos/release : revision 237.7.441

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){

1064

1517

timed out */

1065

1518

1066

1519

if(quit_now){

1520

avahi_s_service_resolver_free(r);

1067

1521

return;

1068

1522

}

1069

1523

1183

1637

__attribute__((nonnull, warn_unused_result))

1184

1638

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

1185

1639

int ret;

1186

error_t ret_errno;

1640

int old_errno;

1187

1641

1188

1642

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

1189

1643

if(s < 0){

1190

ret_errno = errno;

1644

old_errno = errno;

1191

1645

perror_plus("socket");

1192

errno = ret_errno;

1646

errno = old_errno;

1193

1647

return false;

1194

1648

}

1195

strcpy(ifr->ifr_name, ifname);

1649

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

1650

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

1196

1651

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1197

1652

if(ret == -1){

1198

1653

if(debug){

1199

ret_errno = errno;

1654

old_errno = errno;

1200

1655

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1656

errno = old_errno;

1202

1657

}

1203

1658

return false;

1204

1659

}

1335

1790

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

1336

1791

"abcdefghijklmnopqrstuvwxyz"

1337

1792

"0123456789"

1338

"_-");

1793

"_.-");

1339

1794

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

1340

1795

/* Contains non-allowed characters */

1341

1796

if(debug){

1345

1800

return 0;

1346

1801

}

1347

1802

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);

1803

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

1356

1804

if(ret == -1){

1357

1805

if(debug){

1358

1806

perror_plus("Could not stat hook");

1456

1904

}

1457

1905

}

1458

1906

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

1907

__attribute__((nonnull))

1516

1908

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

1517

1909

const float delay){

1518

struct dirent **direntries;

1519

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

1520

alphasort);

1910

struct dirent **direntries = NULL;

1911

if(hookdir_fd == -1){

1912

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1913

| O_CLOEXEC);

1914

if(hookdir_fd == -1){

1915

if(errno == ENOENT){

1916

if(debug){

1917

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

1918

" found\n", hookdir);

1919

}

1920

} else {

1921

perror_plus("open");

1922

}

1923

return;

1924

}

1925

}

1926

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

1927

runnable_hook, alphasort);

1521

1928

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");

1929

perror_plus("scandir");

1930

return;

1931

}

1932

struct dirent *direntry;

1933

int ret;

1934

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

1935

if(devnull == -1){

1936

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

1937

return;

1938

}

1939

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

1940

direntry = direntries[i];

1941

if(debug){

1942

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

1943

direntry->d_name);

1529

1944

}

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){

1945

pid_t hook_pid = fork();

1946

if(hook_pid == 0){

1947

/* Child */

1948

/* Raise privileges */

1949

errno = raise_privileges_permanently();

1950

if(errno != 0){

1951

perror_plus("Failed to raise privileges");

1952

_exit(EX_NOPERM);

1953

}

1954

/* Set group */

1955

errno = 0;

1956

ret = setgid(0);

1957

if(ret == -1){

1958

perror_plus("setgid");

1959

_exit(EX_NOPERM);

1960

}

1961

/* Reset supplementary groups */

1962

errno = 0;

1963

ret = setgroups(0, NULL);

1964

if(ret == -1){

1965

perror_plus("setgroups");

1966

_exit(EX_NOPERM);

1967

}

1968

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

1969

if(ret == -1){

1970

perror_plus("setenv");

1971

_exit(EX_OSERR);

1972

}

1973

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

1974

if(ret == -1){

1975

perror_plus("setenv");

1976

_exit(EX_OSERR);

1977

}

1978

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

1979

if(ret == -1){

1980

perror_plus("setenv");

1981

_exit(EX_OSERR);

1982

}

1983

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

1984

if(ret == -1){

1985

perror_plus("setenv");

1986

_exit(EX_OSERR);

1987

}

1988

char *delaystring;

1989

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

1990

if(ret == -1){

1539

1991

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

}

1992

_exit(EX_OSERR);

1993

}

1994

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

1995

if(ret == -1){

1615

1996

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

}

1997

perror_plus("setenv");

1998

_exit(EX_OSERR);

1999

}

2000

free(delaystring);

2001

if(connect_to != NULL){

2002

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

2003

if(ret == -1){

2004

perror_plus("setenv");

2005

_exit(EX_OSERR);

2006

}

2007

}

2008

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

2009

direntry->d_name,

2010

O_RDONLY));

2011

if(hook_fd == -1){

2012

perror_plus("openat");

2013

_exit(EXIT_FAILURE);

2014

}

2015

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

2016

perror_plus("close");

2017

_exit(EXIT_FAILURE);

2018

}

2019

ret = dup2(devnull, STDIN_FILENO);

2020

if(ret == -1){

2021

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

2022

_exit(EX_OSERR);

2023

}

2024

ret = close(devnull);

2025

if(ret == -1){

2026

perror_plus("close");

2027

_exit(EX_OSERR);

2028

}

2029

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2030

if(ret == -1){

2031

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

2032

_exit(EX_OSERR);

2033

}

2034

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

2035

environ) == -1){

2036

perror_plus("fexecve");

2037

_exit(EXIT_FAILURE);

2038

}

2039

} else {

2040

if(hook_pid == -1){

2041

perror_plus("fork");

2042

free(direntry);

2043

continue;

2044

}

2045

int status;

2046

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

2047

perror_plus("waitpid");

2048

free(direntry);

2049

continue;

2050

}

2051

if(WIFEXITED(status)){

2052

if(WEXITSTATUS(status) != 0){

2053

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

2054

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

2055

WEXITSTATUS(status));

2056

free(direntry);

2057

continue;

2058

}

2059

} else if(WIFSIGNALED(status)){

2060

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

2061

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

2062

WTERMSIG(status));

2063

free(direntry);

2064

continue;

1627

2065

} 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

}

2066

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

2067

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

2068

free(direntry);

2069

continue;

2070

}

2071

}

2072

if(debug){

2073

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

2074

direntry->d_name);

2075

}

2076

free(direntry);

2077

}

2078

free(direntries);

2079

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

2080

perror_plus("close");

2081

} else {

2082

hookdir_fd = -1;

2083

}

2084

close(devnull);

1663

2085

}

1664

2086

1665

2087

__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;

2088

int bring_up_interface(const char *const interface,

2089

const float delay){

2090

int old_errno = errno;

1669

2091

int ret;

1670

2092

struct ifreq network;

1671

2093

unsigned int if_index = if_nametoindex(interface);

1681

2103

}

1682

2104

1683

2105

if(not interface_is_up(interface)){

1684

error_t ret_errno = 0, ioctl_errno = 0;

2106

int ret_errno = 0;

2107

int ioctl_errno = 0;

1685

2108

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

1686

2109

ret_errno = errno;

1687

2110

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

1700

2123

}

1701

2124

1702

2125

if(quit_now){

1703

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

2126

ret = close(sd);

1704

2127

if(ret == -1){

1705

2128

perror_plus("close");

1706

2129

}

1715

2138

1716

2139

/* Raise privileges */

1717

2140

ret_errno = raise_privileges();

2141

if(ret_errno != 0){

2142

errno = ret_errno;

2143

perror_plus("Failed to raise privileges");

2144

}

2145

2146

#ifdef __linux__

2147

int ret_linux;

1718

2148

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

2149

if(ret_errno == 0){

1725

2150

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1726

2151

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

1754

2179

}

1755

2180

1756

2181

/* Close the socket */

1757

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

2182

ret = close(sd);

1758

2183

if(ret == -1){

1759

2184

perror_plus("close");

1760

2185

}

1772

2197

1773

2198

/* Sleep checking until interface is running.

1774

2199

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

1775

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

2200

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

1776

2201

if(interface_is_running(interface)){

1777

2202

break;

1778

2203

}

1788

2213

}

1789

2214

1790

2215

__attribute__((nonnull, warn_unused_result))

1791

error_t take_down_interface(const char *const interface){

1792

error_t old_errno = errno;

2216

int take_down_interface(const char *const interface){

2217

int old_errno = errno;

1793

2218

struct ifreq network;

1794

2219

unsigned int if_index = if_nametoindex(interface);

1795

2220

if(if_index == 0){

1798

2223

return ENXIO;

1799

2224

}

1800

2225

if(interface_is_up(interface)){

1801

error_t ret_errno = 0, ioctl_errno = 0;

2226

int ret_errno = 0;

2227

int ioctl_errno = 0;

1802

2228

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

1803

2229

ret_errno = errno;

1804

2230

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

1824

2250

/* Raise privileges */

1825

2251

ret_errno = raise_privileges();

1826

2252

if(ret_errno != 0){

2253

errno = ret_errno;

1827

2254

perror_plus("Failed to raise privileges");

1828

2255

}

2256

1829

2257

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

1830

2258

ioctl_errno = errno;

1831

2259

1840

2268

}

1841

2269

1842

2270

/* Close the socket */

1843

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

2271

int ret = close(sd);

1844

2272

if(ret == -1){

1845

2273

perror_plus("close");

1846

2274

}

1861

2289

}

1862

2290

1863

2291

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 };

2292

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

2293

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

2294

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

2295

.current_server = NULL, .interfaces = NULL,

2296

.interfaces_size = 0 };

1868

2297

AvahiSServiceBrowser *sb = NULL;

1869

2298

error_t ret_errno;

1870

2299

int ret;

1879

2308

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1880

2309

const char *seckey = PATHDIR "/" SECKEY;

1881

2310

const char *pubkey = PATHDIR "/" PUBKEY;

2311

const char *dh_params_file = NULL;

1882

2312

char *interfaces_hooks = NULL;

1883

2313

1884

2314

bool gnutls_initialized = false;

1937

2367

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

1938

2368

" Diffie-Hellman key exchange",

1939

2369

.group = 2 },

2370

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

2371

.arg = "FILE",

2372

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

2373

" for the Diffie-Hellman key exchange",

2374

.group = 2 },

1940

2375

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

1941

2376

.arg = "STRING",

1942

2377

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

1997

2432

}

1998

2433

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

1999

2434

break;

2435

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

2436

dh_params_file = arg;

2437

break;

2000

2438

case 130: /* --priority */

2001

2439

mc.priority = arg;

2002

2440

break;

2042

2480

.args_doc = "",

2043

2481

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

2044

2482

" passwords from a Mandos server" };

2045

ret = argp_parse(&argp, argc, argv,

2046

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2047

switch(ret){

2483

ret_errno = argp_parse(&argp, argc, argv,

2484

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2485

switch(ret_errno){

2048

2486

case 0:

2049

2487

break;

2050

2488

case ENOMEM:

2051

2489

default:

2052

errno = ret;

2490

errno = ret_errno;

2053

2491

perror_plus("argp_parse");

2054

2492

exitcode = EX_OSERR;

2055

2493

goto end;

2058

2496

goto end;

2059

2497

}

2060

2498

}

2061

2499

2062

2500

{

2063

2501

/* Work around Debian bug #633582:

2064

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

2502

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

2065

2503

2066

2504

/* Re-raise privileges */

2067

ret_errno = raise_privileges();

2068

if(ret_errno != 0){

2069

errno = ret_errno;

2505

ret = raise_privileges();

2506

if(ret != 0){

2507

errno = ret;

2070

2508

perror_plus("Failed to raise privileges");

2071

2509

} else {

2072

2510

struct stat st;

2088

2526

}

2089

2527

}

2090

2528

}

2091

TEMP_FAILURE_RETRY(close(seckey_fd));

2529

close(seckey_fd);

2092

2530

}

2093

2531

}

2094

2532

2095

2533

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

2096

2534

int pubkey_fd = open(pubkey, O_RDONLY);

2097

2535

if(pubkey_fd == -1){

2109

2547

}

2110

2548

}

2111

2549

}

2112

TEMP_FAILURE_RETRY(close(pubkey_fd));

2113

}

2114

}

2115

2550

close(pubkey_fd);

2551

}

2552

}

2553

2554

if(dh_params_file != NULL

2555

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

2556

int dhparams_fd = open(dh_params_file, O_RDONLY);

2557

if(dhparams_fd == -1){

2558

perror_plus("open");

2559

} else {

2560

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

2561

if(ret == -1){

2562

perror_plus("fstat");

2563

} else {

2564

if(S_ISREG(st.st_mode)

2565

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

2566

ret = fchown(dhparams_fd, uid, gid);

2567

if(ret == -1){

2568

perror_plus("fchown");

2569

}

2570

}

2571

}

2572

close(dhparams_fd);

2573

}

2574

}

2575

2116

2576

/* Lower privileges */

2117

ret_errno = lower_privileges();

2118

if(ret_errno != 0){

2119

errno = ret_errno;

2577

ret = lower_privileges();

2578

if(ret != 0){

2579

errno = ret;

2120

2580

perror_plus("Failed to lower privileges");

2121

2581

}

2122

2582

}

2235

2695

2236

2696

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

2237

2697

if(mc.interfaces == NULL){

2238

struct dirent **direntries;

2698

struct dirent **direntries = NULL;

2239

2699

/* Look for any good interfaces */

2240

2700

ret = scandir(sys_class_net, &direntries, good_interface,

2241

2701

alphasort);

2247

2707

if(ret_errno != 0){

2248

2708

errno = ret_errno;

2249

2709

perror_plus("argz_add");

2710

free(direntries[i]);

2250

2711

continue;

2251

2712

}

2252

2713

if(debug){

2253

2714

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

2254

2715

direntries[i]->d_name);

2255

2716

}

2717

free(direntries[i]);

2256

2718

}

2257

2719

free(direntries);

2258

2720

} else {

2259

free(direntries);

2721

if(ret == 0){

2722

free(direntries);

2723

}

2260

2724

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

2261

2725

exitcode = EXIT_FAILURE;

2262

2726

goto end;

2288

2752

errno = bring_up_interface(interface, delay);

2289

2753

if(not interface_was_up){

2290

2754

if(errno != 0){

2291

perror_plus("Failed to bring up interface");

2755

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

2756

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

2292

2757

} else {

2293

2758

errno = argz_add(&interfaces_to_take_down,

2294

2759

&interfaces_to_take_down_size,

2317

2782

goto end;

2318

2783

}

2319

2784

2320

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

2785

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

2321

2786

if(ret == -1){

2322

2787

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

2323

2788

exitcode = EX_UNAVAILABLE;

2445

2910

2446

2911

/* Allocate a new server */

2447

2912

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2448

&config, NULL, NULL, &ret_errno);

2913

&config, NULL, NULL, &ret);

2449

2914

2450

2915

/* Free the Avahi configuration data */

2451

2916

avahi_server_config_free(&config);

2454

2919

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

2455

2920

if(mc.server == NULL){

2456

2921

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

2457

avahi_strerror(ret_errno));

2922

avahi_strerror(ret));

2458

2923

exitcode = EX_UNAVAILABLE;

2459

2924

goto end;

2460

2925

}

2484

2949

if(debug){

2485

2950

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

2486

2951

}

2487

2952

2488

2953

ret = avahi_loop_with_timeout(simple_poll,

2489

2954

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

2490

2955

if(debug){

2495

2960

end:

2496

2961

2497

2962

if(debug){

2498

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

2963

if(signal_received){

2964

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

2965

argv[0], signal_received,

2966

strsignal(signal_received));

2967

} else {

2968

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

2969

}

2499

2970

}

2500

2971

2501

2972

/* Cleanup things */

2512

2983

2513

2984

if(gnutls_initialized){

2514

2985

gnutls_certificate_free_credentials(mc.cred);

2515

gnutls_global_deinit();

2516

2986

gnutls_dh_params_deinit(mc.dh_params);

2517

2987

}

2518

2988

2526

2996

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

2527

2997

while(mc.current_server != NULL){

2528

2998

server *next = mc.current_server->next;

2999

#ifdef __GNUC__

3000

#pragma GCC diagnostic push

3001

#pragma GCC diagnostic ignored "-Wcast-qual"

3002

#endif

3003

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

3004

#ifdef __GNUC__

3005

#pragma GCC diagnostic pop

3006

#endif

2529

3007

free(mc.current_server);

2530

3008

mc.current_server = next;

2531

3009

}

2533

3011

2534

3012

/* Re-raise privileges */

2535

3013

{

2536

ret_errno = raise_privileges();

2537

if(ret_errno != 0){

3014

ret = raise_privileges();

3015

if(ret != 0){

3016

errno = ret;

2538

3017

perror_plus("Failed to raise privileges");

2539

3018

} else {

2540

3019

2545

3024

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

2546

3025

{

2547

3026

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;

3027

while((interface = argz_next(interfaces_to_take_down,

3028

interfaces_to_take_down_size,

3029

interface))){

3030

ret = take_down_interface(interface);

3031

if(ret != 0){

3032

errno = ret;

2554

3033

perror_plus("Failed to take down interface");

2555

3034

}

2556

3035

}

2560

3039

}

2561

3040

}

2562

3041

}

2563

ret_errno = lower_privileges_permanently();

2564

if(ret_errno != 0){

3042

3043

ret = lower_privileges_permanently();

3044

if(ret != 0){

3045

errno = ret;

2565

3046

perror_plus("Failed to lower privileges permanently");

2566

3047

}

2567

3048

}

2569

3050

free(interfaces_to_take_down);

2570

3051

free(interfaces_hooks);

2571

3052

3053

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

3054

uintmax_t level){

3055

struct dirent **direntries = NULL;

3056

int dret;

3057

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

3058

O_RDONLY

3059

| O_NOFOLLOW

3060

| O_DIRECTORY

3061

| O_PATH));

3062

if(dir_fd == -1){

3063

perror_plus("open");

3064

}

3065

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

3066

notdotentries, alphasort);

3067

if(numentries >= 0){

3068

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

3069

if(debug){

3070

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

3071

dirname, direntries[i]->d_name);

3072

}

3073

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

3074

if(dret == -1){

3075

if(errno == EISDIR){

3076

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

3077

AT_REMOVEDIR);

3078

}

3079

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

3080

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

3081

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

3082

/* Recurse only in this special case */

3083

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

3084

dret = 0;

3085

}

3086

if(dret == -1){

3087

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

3088

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

3089

}

3090

}

3091

free(direntries[i]);

3092

}

3093

3094

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

3095

free(direntries);

3096

if(numentries == -1){

3097

perror_plus("scandirat");

3098

}

3099

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3100

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

3101

perror_plus("rmdir");

3102

}

3103

} else {

3104

perror_plus("scandirat");

3105

}

3106

close(dir_fd);

3107

}

3108

2572

3109

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

2573

3110

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

}

3111

clean_dir_at(-1, tempdir, 0);

2606

3112

}

2607

3113

2608

3114

if(quit_now){