/mandos/release : revision 237.7.416

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() */

51

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

52

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

53

sockaddr_in6, PF_INET6,

57

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

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

61

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

62

*/

63

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

64

strtoimax() */

65

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

65

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

66

EAI_SYSTEM, ENETUNREACH,

67

EHOSTUNREACH, ECONNREFUSED, EPROTO,

68

EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

69

ENOTEMPTY,

66

70

program_invocation_short_name */

67

71

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

68

72

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

73

77

*/

74

78

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

75

79

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

76

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

80

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

81

unlinkat() */

77

82

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

78

83

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

79

84

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

141

146

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

142

147

char *connect_to = NULL;

143

148

const char *hookdir = HOOKDIR;

149

int hookdir_fd = -1;

144

150

uid_t uid = 65534;

145

151

gid_t gid = 65534;

146

152

232

238

.af = af };

233

239

if(new_server->ip == NULL){

234

240

perror_plus("strdup");

241

free(new_server);

235

242

return false;

236

243

}

237

244

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

238

245

if(ret == -1){

239

246

perror_plus("clock_gettime");

247

#ifdef __GNUC__

248

#pragma GCC diagnostic push

249

#pragma GCC diagnostic ignored "-Wcast-qual"

250

#endif

251

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

252

#ifdef __GNUC__

253

#pragma GCC diagnostic pop

254

#endif

255

free(new_server);

240

256

return false;

241

257

}

242

258

/* Special case of first server */

258

274

* Initialize GPGME.

259

275

*/

260

276

__attribute__((nonnull, warn_unused_result))

261

static bool init_gpgme(const char *seckey, const char *pubkey,

262

const char *tempdir, mandos_context *mc){

277

static bool init_gpgme(const char * const seckey,

278

const char * const pubkey,

279

const char * const tempdir,

280

mandos_context *mc){

263

281

gpgme_error_t rc;

264

282

gpgme_engine_info_t engine_info;

265

283

266

284

/*

267

285

* Helper function to insert pub and seckey to the engine keyring.

268

286

*/

269

bool import_key(const char *filename){

287

bool import_key(const char * const filename){

270

288

int ret;

271

289

int fd;

272

290

gpgme_data_t pgp_data;

291

309

return false;

292

310

}

293

311

294

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

312

ret = close(fd);

295

313

if(ret == -1){

296

314

perror_plus("close");

297

315

}

479

497

return plaintext_length;

480

498

}

481

499

500

__attribute__((warn_unused_result, const))

501

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

502

if(str == NULL)

503

return "(unknown)";

504

return str;

505

}

506

482

507

__attribute__((warn_unused_result))

483

508

static const char *safer_gnutls_strerror(int value){

484

509

const char *ret = gnutls_strerror(value);

485

if(ret == NULL)

486

ret = "(unknown)";

487

return ret;

510

return safe_string(ret);

488

511

}

489

512

490

513

/* GnuTLS log function callback */

494

517

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

495

518

}

496

519

497

__attribute__((nonnull, warn_unused_result))

520

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

498

521

static int init_gnutls_global(const char *pubkeyfilename,

499

522

const char *seckeyfilename,

523

const char *dhparamsfilename,

500

524

mandos_context *mc){

501

525

int ret;

526

unsigned int uret;

502

527

503

528

if(debug){

504

529

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

505

530

}

506

531

507

ret = gnutls_global_init();

508

if(ret != GNUTLS_E_SUCCESS){

509

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

510

safer_gnutls_strerror(ret));

511

return -1;

512

}

513

514

532

if(debug){

515

533

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

516

534

* - GnuTLS manual

524

542

if(ret != GNUTLS_E_SUCCESS){

525

543

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

526

544

safer_gnutls_strerror(ret));

527

gnutls_global_deinit();

528

545

return -1;

529

546

}

530

547

555

572

safer_gnutls_strerror(ret));

556

573

goto globalfail;

557

574

}

558

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

559

if(ret != GNUTLS_E_SUCCESS){

560

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

561

safer_gnutls_strerror(ret));

562

goto globalfail;

563

}

564

575

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

576

if(dhparamsfilename != NULL){

577

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

578

do {

579

int dhpfile = open(dhparamsfilename, O_RDONLY);

580

if(dhpfile == -1){

581

perror_plus("open");

582

dhparamsfilename = NULL;

583

break;

584

}

585

size_t params_capacity = 0;

586

while(true){

587

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

588

(size_t)params.size,

589

(size_t)params_capacity);

590

if(params_capacity == 0){

591

perror_plus("incbuffer");

592

free(params.data);

593

params.data = NULL;

594

dhparamsfilename = NULL;

595

break;

596

}

597

ssize_t bytes_read = read(dhpfile,

598

params.data + params.size,

599

BUFFER_SIZE);

600

/* EOF */

601

if(bytes_read == 0){

602

break;

603

}

604

/* check bytes_read for failure */

605

if(bytes_read < 0){

606

perror_plus("read");

607

free(params.data);

608

params.data = NULL;

609

dhparamsfilename = NULL;

610

break;

611

}

612

params.size += (unsigned int)bytes_read;

613

}

614

if(params.data == NULL){

615

dhparamsfilename = NULL;

616

}

617

if(dhparamsfilename == NULL){

618

break;

619

}

620

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

621

GNUTLS_X509_FMT_PEM);

622

if(ret != GNUTLS_E_SUCCESS){

623

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

624

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

625

safer_gnutls_strerror(ret));

626

dhparamsfilename = NULL;

627

}

628

} while(false);

629

}

630

if(dhparamsfilename == NULL){

631

if(mc->dh_bits == 0){

632

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

633

/* Try to read the private key file */

634

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

635

do {

636

int secfile = open(seckeyfilename, O_RDONLY);

637

if(secfile == -1){

638

perror_plus("open");

639

break;

640

}

641

size_t buffer_capacity = 0;

642

while(true){

643

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

644

(size_t)buffer.size,

645

(size_t)buffer_capacity);

646

if(buffer_capacity == 0){

647

perror_plus("incbuffer");

648

free(buffer.data);

649

buffer.data = NULL;

650

break;

651

}

652

ssize_t bytes_read = read(secfile,

653

buffer.data + buffer.size,

654

BUFFER_SIZE);

655

/* EOF */

656

if(bytes_read == 0){

657

break;

658

}

659

/* check bytes_read for failure */

660

if(bytes_read < 0){

661

perror_plus("read");

662

free(buffer.data);

663

buffer.data = NULL;

664

break;

665

}

666

buffer.size += (unsigned int)bytes_read;

667

}

668

close(secfile);

669

} while(false);

670

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

671

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

672

if(buffer.data != NULL){

673

{

674

gnutls_openpgp_privkey_t privkey = NULL;

675

ret = gnutls_openpgp_privkey_init(&privkey);

676

if(ret != GNUTLS_E_SUCCESS){

677

fprintf_plus(stderr, "Error initializing OpenPGP key"

678

" structure: %s",

679

safer_gnutls_strerror(ret));

680

free(buffer.data);

681

buffer.data = NULL;

682

} else {

683

ret = gnutls_openpgp_privkey_import

684

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

685

if(ret != GNUTLS_E_SUCCESS){

686

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

687

safer_gnutls_strerror(ret));

688

privkey = NULL;

689

}

690

free(buffer.data);

691

buffer.data = NULL;

692

if(privkey != NULL){

693

/* Use private key to suggest an appropriate

694

sec_param */

695

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

696

gnutls_openpgp_privkey_deinit(privkey);

697

if(debug){

698

fprintf_plus(stderr, "This OpenPGP key implies using"

699

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

700

safe_string(gnutls_sec_param_get_name

701

(sec_param)));

702

}

703

}

704

}

705

}

706

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

707

/* Err on the side of caution */

708

sec_param = GNUTLS_SEC_PARAM_ULTRA;

709

if(debug){

710

fprintf_plus(stderr, "Falling back to security parameter"

711

" \"%s\"\n",

712

safe_string(gnutls_sec_param_get_name

713

(sec_param)));

714

}

715

}

716

}

717

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

718

if(uret != 0){

719

mc->dh_bits = uret;

720

if(debug){

721

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

722

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

723

safe_string(gnutls_sec_param_get_name

724

(sec_param)),

725

mc->dh_bits);

726

}

727

} else {

728

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

729

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

730

safe_string(gnutls_sec_param_get_name

731

(sec_param)),

732

safer_gnutls_strerror(ret));

733

goto globalfail;

734

}

735

} else if(debug){

736

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

737

mc->dh_bits);

738

}

739

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

740

if(ret != GNUTLS_E_SUCCESS){

741

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

742

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

743

safer_gnutls_strerror(ret));

744

goto globalfail;

745

}

746

}

565

747

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

566

748

567

749

return 0;

569

751

globalfail:

570

752

571

753

gnutls_certificate_free_credentials(mc->cred);

572

gnutls_global_deinit();

573

754

gnutls_dh_params_deinit(mc->dh_params);

574

755

return -1;

575

756

}

627

808

/* ignore client certificate if any. */

628

809

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

629

810

630

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

631

632

811

return 0;

633

812

}

634

813

636

815

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

637

816

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

638

817

818

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

819

__attribute__((warn_unused_result))

820

int raise_privileges(void){

821

int old_errno = errno;

822

int ret = 0;

823

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

824

ret = errno;

825

}

826

errno = old_errno;

827

return ret;

828

}

829

830

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

831

__attribute__((warn_unused_result))

832

int raise_privileges_permanently(void){

833

int old_errno = errno;

834

int ret = raise_privileges();

835

if(ret != 0){

836

errno = old_errno;

837

return ret;

838

}

839

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

840

ret = errno;

841

}

842

errno = old_errno;

843

return ret;

844

}

845

846

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

847

__attribute__((warn_unused_result))

848

int lower_privileges(void){

849

int old_errno = errno;

850

int ret = 0;

851

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

852

ret = errno;

853

}

854

errno = old_errno;

855

return ret;

856

}

857

858

/* Lower privileges permanently */

859

__attribute__((warn_unused_result))

860

int lower_privileges_permanently(void){

861

int old_errno = errno;

862

int ret = 0;

863

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

864

ret = errno;

865

}

866

errno = old_errno;

867

return ret;

868

}

869

870

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

871

__attribute__((nonnull, warn_unused_result))

872

static bool add_delete_local_route(const bool add,

873

const char *address,

874

AvahiIfIndex if_index){

875

int ret;

876

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

877

char add_arg[] = "add";

878

char delete_arg[] = "delete";

879

char debug_flag[] = "--debug";

880

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

881

if(pluginhelperdir == NULL){

882

if(debug){

883

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

884

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

885

}

886

return false;

887

}

888

889

char interface[IF_NAMESIZE];

890

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

891

perror_plus("if_indextoname");

892

return false;

893

}

894

895

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

896

if(devnull == -1){

897

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

898

return false;

899

}

900

pid_t pid = fork();

901

if(pid == 0){

902

/* Child */

903

/* Raise privileges */

904

errno = raise_privileges_permanently();

905

if(errno != 0){

906

perror_plus("Failed to raise privileges");

907

/* _exit(EX_NOPERM); */

908

} else {

909

/* Set group */

910

errno = 0;

911

ret = setgid(0);

912

if(ret == -1){

913

perror_plus("setgid");

914

_exit(EX_NOPERM);

915

}

916

/* Reset supplementary groups */

917

errno = 0;

918

ret = setgroups(0, NULL);

919

if(ret == -1){

920

perror_plus("setgroups");

921

_exit(EX_NOPERM);

922

}

923

}

924

ret = dup2(devnull, STDIN_FILENO);

925

if(ret == -1){

926

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

927

_exit(EX_OSERR);

928

}

929

ret = close(devnull);

930

if(ret == -1){

931

perror_plus("close");

932

_exit(EX_OSERR);

933

}

934

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

935

if(ret == -1){

936

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

937

_exit(EX_OSERR);

938

}

939

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

940

O_RDONLY

941

| O_DIRECTORY

942

| O_PATH

943

| O_CLOEXEC));

944

if(helperdir_fd == -1){

945

perror_plus("open");

946

_exit(EX_UNAVAILABLE);

947

}

948

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

949

helper, O_RDONLY));

950

if(helper_fd == -1){

951

perror_plus("openat");

952

close(helperdir_fd);

953

_exit(EX_UNAVAILABLE);

954

}

955

close(helperdir_fd);

956

#ifdef __GNUC__

957

#pragma GCC diagnostic push

958

#pragma GCC diagnostic ignored "-Wcast-qual"

959

#endif

960

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

961

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

962

interface, debug ? debug_flag : NULL, NULL },

963

environ) == -1){

964

#ifdef __GNUC__

965

#pragma GCC diagnostic pop

966

#endif

967

perror_plus("fexecve");

968

_exit(EXIT_FAILURE);

969

}

970

}

971

if(pid == -1){

972

perror_plus("fork");

973

return false;

974

}

975

int status;

976

pid_t pret = -1;

977

errno = 0;

978

do {

979

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

980

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

981

int errno_raising = 0;

982

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

983

errno_raising = errno;

984

perror_plus("Failed to raise privileges in order to"

985

" kill helper program");

986

}

987

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

988

perror_plus("kill");

989

}

990

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

991

perror_plus("Failed to lower privileges after killing"

992

" helper program");

993

}

994

return false;

995

}

996

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

997

if(pret == -1){

998

perror_plus("waitpid");

999

return false;

1000

}

1001

if(WIFEXITED(status)){

1002

if(WEXITSTATUS(status) != 0){

1003

fprintf_plus(stderr, "Error: iprouteadddel exited"

1004

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

1005

return false;

1006

}

1007

return true;

1008

}

1009

if(WIFSIGNALED(status)){

1010

fprintf_plus(stderr, "Error: iprouteadddel died by"

1011

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

1012

return false;

1013

}

1014

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

1015

return false;

1016

}

1017

1018

__attribute__((nonnull, warn_unused_result))

1019

static bool add_local_route(const char *address,

1020

AvahiIfIndex if_index){

1021

if(debug){

1022

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

1023

}

1024

return add_delete_local_route(true, address, if_index);

1025

}

1026

1027

__attribute__((nonnull, warn_unused_result))

1028

static bool delete_local_route(const char *address,

1029

AvahiIfIndex if_index){

1030

if(debug){

1031

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

1032

}

1033

return add_delete_local_route(false, address, if_index);

1034

}

1035

639

1036

/* Called when a Mandos server is found */

640

1037

__attribute__((nonnull, warn_unused_result))

641

1038

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

652

1049

int retval = -1;

653

1050

gnutls_session_t session;

654

1051

int pf; /* Protocol family */

1052

bool route_added = false;

655

1053

656

1054

errno = 0;

657

1055

715

1113

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

716

1114

}

717

1115

718

tcp_sd = socket(pf, SOCK_STREAM, 0);

1116

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

719

1117

if(tcp_sd < 0){

720

1118

int e = errno;

721

1119

perror_plus("socket");

728

1126

goto mandos_end;

729

1127

}

730

1128

731

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

732

1129

if(af == AF_INET6){

733

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

734

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

1130

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

1131

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

1132

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

735

1133

} else { /* IPv4 */

736

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

737

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

1134

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

1135

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

1136

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

738

1137

}

739

1138

if(ret < 0 ){

740

1139

int e = errno;

810

1209

goto mandos_end;

811

1210

}

812

1211

813

if(af == AF_INET6){

814

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

815

sizeof(struct sockaddr_in6));

816

} else {

817

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

818

sizeof(struct sockaddr_in));

819

}

820

if(ret < 0){

821

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

822

int e = errno;

823

perror_plus("connect");

824

errno = e;

825

}

826

goto mandos_end;

827

}

828

829

if(quit_now){

830

errno = EINTR;

831

goto mandos_end;

1212

while(true){

1213

if(af == AF_INET6){

1214

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

1215

sizeof(struct sockaddr_in6));

1216

} else {

1217

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

1218

sizeof(struct sockaddr_in));

1219

}

1220

if(ret < 0){

1221

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

1222

and if_index != AVAHI_IF_UNSPEC

1223

and connect_to == NULL

1224

and not route_added and

1225

((af == AF_INET6 and not

1226

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1227

&to)->sin6_addr)))

1228

or (af == AF_INET and

1229

/* Not a a IPv4LL address */

1230

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

1231

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

1232

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

1233

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

1234

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

1235

connect to a Mandos server announced by Avahi on a server

1236

host with a global address. Work around this by retrying

1237

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

1238

1239

Avahi bug reference:

1240

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

1241

https://bugs.debian.org/587961

1242

*/

1243

if(debug){

1244

fprintf_plus(stderr, "Mandos server unreachable, trying"

1245

" direct route\n");

1246

}

1247

int e = errno;

1248

route_added = add_local_route(ip, if_index);

1249

if(route_added){

1250

continue;

1251

}

1252

errno = e;

1253

}

1254

if(errno != ECONNREFUSED or debug){

1255

int e = errno;

1256

perror_plus("connect");

1257

errno = e;

1258

}

1259

goto mandos_end;

1260

}

1261

1262

if(quit_now){

1263

errno = EINTR;

1264

goto mandos_end;

1265

}

1266

break;

832

1267

}

833

1268

834

1269

const char *out = mandos_protocol_version;

988

1423

&decrypted_buffer, mc);

989

1424

if(decrypted_buffer_size >= 0){

990

1425

1426

clearerr(stdout);

991

1427

written = 0;

992

1428

while(written < (size_t) decrypted_buffer_size){

993

1429

if(quit_now){

1009

1445

}

1010

1446

written += (size_t)ret;

1011

1447

}

1448

ret = fflush(stdout);

1449

if(ret != 0){

1450

int e = errno;

1451

if(debug){

1452

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

1453

strerror(errno));

1454

}

1455

errno = e;

1456

goto mandos_end;

1457

}

1012

1458

retval = 0;

1013

1459

}

1014

1460

}

1017

1463

1018

1464

mandos_end:

1019

1465

{

1466

if(route_added){

1467

if(not delete_local_route(ip, if_index)){

1468

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

1469

" interface %d", ip, if_index);

1470

}

1471

}

1020

1472

int e = errno;

1021

1473

free(decrypted_buffer);

1022

1474

free(buffer);

1023

1475

if(tcp_sd >= 0){

1024

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

1476

ret = close(tcp_sd);

1025

1477

}

1026

1478

if(ret == -1){

1027

1479

if(e == 0){

1062

1514

timed out */

1063

1515

1064

1516

if(quit_now){

1517

avahi_s_service_resolver_free(r);

1065

1518

return;

1066

1519

}

1067

1520

1181

1634

__attribute__((nonnull, warn_unused_result))

1182

1635

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

1183

1636

int ret;

1184

error_t ret_errno;

1637

int old_errno;

1185

1638

1186

1639

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

1187

1640

if(s < 0){

1188

ret_errno = errno;

1641

old_errno = errno;

1189

1642

perror_plus("socket");

1190

errno = ret_errno;

1643

errno = old_errno;

1191

1644

return false;

1192

1645

}

1193

strcpy(ifr->ifr_name, ifname);

1646

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

1647

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

1194

1648

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1195

1649

if(ret == -1){

1196

1650

if(debug){

1197

ret_errno = errno;

1651

old_errno = errno;

1198

1652

perror_plus("ioctl SIOCGIFFLAGS");

1199

errno = ret_errno;

1653

errno = old_errno;

1200

1654

}

1201

1655

return false;

1202

1656

}

1333

1787

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

1334

1788

"abcdefghijklmnopqrstuvwxyz"

1335

1789

"0123456789"

1336

"_-");

1790

"_.-");

1337

1791

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

1338

1792

/* Contains non-allowed characters */

1339

1793

if(debug){

1343

1797

return 0;

1344

1798

}

1345

1799

1346

char *fullname = NULL;

1347

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

1348

if(ret < 0){

1349

perror_plus("asprintf");

1350

return 0;

1351

}

1352

1353

ret = stat(fullname, &st);

1800

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

1354

1801

if(ret == -1){

1355

1802

if(debug){

1356

1803

perror_plus("Could not stat hook");

1454

1901

}

1455

1902

}

1456

1903

1457

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

1458

__attribute__((warn_unused_result))

1459

error_t raise_privileges(void){

1460

error_t old_errno = errno;

1461

error_t ret_errno = 0;

1462

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

1463

ret_errno = errno;

1464

perror_plus("seteuid");

1465

}

1466

errno = old_errno;

1467

return ret_errno;

1468

}

1469

1470

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

1471

__attribute__((warn_unused_result))

1472

error_t raise_privileges_permanently(void){

1473

error_t old_errno = errno;

1474

error_t ret_errno = raise_privileges();

1475

if(ret_errno != 0){

1476

errno = old_errno;

1477

return ret_errno;

1478

}

1479

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

1480

ret_errno = errno;

1481

perror_plus("seteuid");

1482

}

1483

errno = old_errno;

1484

return ret_errno;

1485

}

1486

1487

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

1488

__attribute__((warn_unused_result))

1489

error_t lower_privileges(void){

1490

error_t old_errno = errno;

1491

error_t ret_errno = 0;

1492

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

1493

ret_errno = errno;

1494

perror_plus("seteuid");

1495

}

1496

errno = old_errno;

1497

return ret_errno;

1498

}

1499

1500

/* Lower privileges permanently */

1501

__attribute__((warn_unused_result))

1502

error_t lower_privileges_permanently(void){

1503

error_t old_errno = errno;

1504

error_t ret_errno = 0;

1505

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

1506

ret_errno = errno;

1507

perror_plus("setuid");

1508

}

1509

errno = old_errno;

1510

return ret_errno;

1511

}

1512

1513

1904

__attribute__((nonnull))

1514

1905

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

1515

1906

const float delay){

1516

struct dirent **direntries;

1517

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

1518

alphasort);

1907

struct dirent **direntries = NULL;

1908

if(hookdir_fd == -1){

1909

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1910

| O_CLOEXEC);

1911

if(hookdir_fd == -1){

1912

if(errno == ENOENT){

1913

if(debug){

1914

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

1915

" found\n", hookdir);

1916

}

1917

} else {

1918

perror_plus("open");

1919

}

1920

return;

1921

}

1922

}

1923

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

1924

runnable_hook, alphasort);

1519

1925

if(numhooks == -1){

1520

if(errno == ENOENT){

1521

if(debug){

1522

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

1523

" found\n", hookdir);

1524

}

1525

} else {

1526

perror_plus("scandir");

1926

perror_plus("scandir");

1927

return;

1928

}

1929

struct dirent *direntry;

1930

int ret;

1931

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

1932

if(devnull == -1){

1933

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

1934

return;

1935

}

1936

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

1937

direntry = direntries[i];

1938

if(debug){

1939

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

1940

direntry->d_name);

1527

1941

}

1528

} else {

1529

struct dirent *direntry;

1530

int ret;

1531

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

1532

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

1533

direntry = direntries[i];

1534

char *fullname = NULL;

1535

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

1536

if(ret < 0){

1942

pid_t hook_pid = fork();

1943

if(hook_pid == 0){

1944

/* Child */

1945

/* Raise privileges */

1946

errno = raise_privileges_permanently();

1947

if(errno != 0){

1948

perror_plus("Failed to raise privileges");

1949

_exit(EX_NOPERM);

1950

}

1951

/* Set group */

1952

errno = 0;

1953

ret = setgid(0);

1954

if(ret == -1){

1955

perror_plus("setgid");

1956

_exit(EX_NOPERM);

1957

}

1958

/* Reset supplementary groups */

1959

errno = 0;

1960

ret = setgroups(0, NULL);

1961

if(ret == -1){

1962

perror_plus("setgroups");

1963

_exit(EX_NOPERM);

1964

}

1965

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

1966

if(ret == -1){

1967

perror_plus("setenv");

1968

_exit(EX_OSERR);

1969

}

1970

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

1971

if(ret == -1){

1972

perror_plus("setenv");

1973

_exit(EX_OSERR);

1974

}

1975

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

1976

if(ret == -1){

1977

perror_plus("setenv");

1978

_exit(EX_OSERR);

1979

}

1980

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

1981

if(ret == -1){

1982

perror_plus("setenv");

1983

_exit(EX_OSERR);

1984

}

1985

char *delaystring;

1986

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

1987

if(ret == -1){

1537

1988

perror_plus("asprintf");

1538

continue;

1539

}

1540

if(debug){

1541

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

1542

direntry->d_name);

1543

}

1544

pid_t hook_pid = fork();

1545

if(hook_pid == 0){

1546

/* Child */

1547

/* Raise privileges */

1548

if(raise_privileges_permanently() != 0){

1549

perror_plus("Failed to raise privileges");

1550

_exit(EX_NOPERM);

1551

}

1552

/* Set group */

1553

errno = 0;

1554

ret = setgid(0);

1555

if(ret == -1){

1556

perror_plus("setgid");

1557

_exit(EX_NOPERM);

1558

}

1559

/* Reset supplementary groups */

1560

errno = 0;

1561

ret = setgroups(0, NULL);

1562

if(ret == -1){

1563

perror_plus("setgroups");

1564

_exit(EX_NOPERM);

1565

}

1566

ret = dup2(devnull, STDIN_FILENO);

1567

if(ret == -1){

1568

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

1569

_exit(EX_OSERR);

1570

}

1571

ret = close(devnull);

1572

if(ret == -1){

1573

perror_plus("close");

1574

_exit(EX_OSERR);

1575

}

1576

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1577

if(ret == -1){

1578

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

1579

_exit(EX_OSERR);

1580

}

1581

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

1582

if(ret == -1){

1583

perror_plus("setenv");

1584

_exit(EX_OSERR);

1585

}

1586

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

1587

if(ret == -1){

1588

perror_plus("setenv");

1589

_exit(EX_OSERR);

1590

}

1591

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

1592

if(ret == -1){

1593

perror_plus("setenv");

1594

_exit(EX_OSERR);

1595

}

1596

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

1597

if(ret == -1){

1598

perror_plus("setenv");

1599

_exit(EX_OSERR);

1600

}

1601

char *delaystring;

1602

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

1603

if(ret == -1){

1604

perror_plus("asprintf");

1605

_exit(EX_OSERR);

1606

}

1607

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

1608

if(ret == -1){

1609

free(delaystring);

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1989

_exit(EX_OSERR);

1990

}

1991

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

1992

if(ret == -1){

1613

1993

free(delaystring);

1614

if(connect_to != NULL){

1615

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

1616

if(ret == -1){

1617

perror_plus("setenv");

1618

_exit(EX_OSERR);

1619

}

1620

}

1621

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

1622

perror_plus("execl");

1623

_exit(EXIT_FAILURE);

1624

}

1994

perror_plus("setenv");

1995

_exit(EX_OSERR);

1996

}

1997

free(delaystring);

1998

if(connect_to != NULL){

1999

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

2000

if(ret == -1){

2001

perror_plus("setenv");

2002

_exit(EX_OSERR);

2003

}

2004

}

2005

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

2006

direntry->d_name,

2007

O_RDONLY));

2008

if(hook_fd == -1){

2009

perror_plus("openat");

2010

_exit(EXIT_FAILURE);

2011

}

2012

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

2013

perror_plus("close");

2014

_exit(EXIT_FAILURE);

2015

}

2016

ret = dup2(devnull, STDIN_FILENO);

2017

if(ret == -1){

2018

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

2019

_exit(EX_OSERR);

2020

}

2021

ret = close(devnull);

2022

if(ret == -1){

2023

perror_plus("close");

2024

_exit(EX_OSERR);

2025

}

2026

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2027

if(ret == -1){

2028

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

2029

_exit(EX_OSERR);

2030

}

2031

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

2032

environ) == -1){

2033

perror_plus("fexecve");

2034

_exit(EXIT_FAILURE);

2035

}

2036

} else {

2037

if(hook_pid == -1){

2038

perror_plus("fork");

2039

free(direntry);

2040

continue;

2041

}

2042

int status;

2043

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

2044

perror_plus("waitpid");

2045

free(direntry);

2046

continue;

2047

}

2048

if(WIFEXITED(status)){

2049

if(WEXITSTATUS(status) != 0){

2050

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

2051

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

2052

WEXITSTATUS(status));

2053

free(direntry);

2054

continue;

2055

}

2056

} else if(WIFSIGNALED(status)){

2057

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

2058

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

2059

WTERMSIG(status));

2060

free(direntry);

2061

continue;

1625

2062

} else {

1626

int status;

1627

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

1628

perror_plus("waitpid");

1629

free(fullname);

1630

continue;

1631

}

1632

if(WIFEXITED(status)){

1633

if(WEXITSTATUS(status) != 0){

1634

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

1635

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

1636

WEXITSTATUS(status));

1637

free(fullname);

1638

continue;

1639

}

1640

} else if(WIFSIGNALED(status)){

1641

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

1642

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

1643

WTERMSIG(status));

1644

free(fullname);

1645

continue;

1646

} else {

1647

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

1648

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

1649

free(fullname);

1650

continue;

1651

}

1652

}

1653

free(fullname);

1654

if(debug){

1655

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

1656

direntry->d_name);

1657

}

1658

}

1659

close(devnull);

1660

}

2063

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

2064

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

2065

free(direntry);

2066

continue;

2067

}

2068

}

2069

if(debug){

2070

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

2071

direntry->d_name);

2072

}

2073

free(direntry);

2074

}

2075

free(direntries);

2076

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

2077

perror_plus("close");

2078

} else {

2079

hookdir_fd = -1;

2080

}

2081

close(devnull);

1661

2082

}

1662

2083

1663

2084

__attribute__((nonnull, warn_unused_result))

1664

error_t bring_up_interface(const char *const interface,

1665

const float delay){

1666

error_t old_errno = errno;

2085

int bring_up_interface(const char *const interface,

2086

const float delay){

2087

int old_errno = errno;

1667

2088

int ret;

1668

2089

struct ifreq network;

1669

2090

unsigned int if_index = if_nametoindex(interface);

1679

2100

}

1680

2101

1681

2102

if(not interface_is_up(interface)){

1682

error_t ret_errno = 0, ioctl_errno = 0;

2103

int ret_errno = 0;

2104

int ioctl_errno = 0;

1683

2105

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

1684

2106

ret_errno = errno;

1685

2107

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

1698

2120

}

1699

2121

1700

2122

if(quit_now){

1701

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

2123

ret = close(sd);

1702

2124

if(ret == -1){

1703

2125

perror_plus("close");

1704

2126

}

1713

2135

1714

2136

/* Raise privileges */

1715

2137

ret_errno = raise_privileges();

2138

if(ret_errno != 0){

2139

errno = ret_errno;

2140

perror_plus("Failed to raise privileges");

2141

}

2142

2143

#ifdef __linux__

2144

int ret_linux;

1716

2145

bool restore_loglevel = false;

1717

if(ret_errno != 0){

1718

perror_plus("Failed to raise privileges");

1719

}

1720

#ifdef __linux__

1721

int ret_linux;

1722

2146

if(ret_errno == 0){

1723

2147

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1724

2148

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

1752

2176

}

1753

2177

1754

2178

/* Close the socket */

1755

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

2179

ret = close(sd);

1756

2180

if(ret == -1){

1757

2181

perror_plus("close");

1758

2182

}

1786

2210

}

1787

2211

1788

2212

__attribute__((nonnull, warn_unused_result))

1789

error_t take_down_interface(const char *const interface){

1790

error_t old_errno = errno;

2213

int take_down_interface(const char *const interface){

2214

int old_errno = errno;

1791

2215

struct ifreq network;

1792

2216

unsigned int if_index = if_nametoindex(interface);

1793

2217

if(if_index == 0){

1796

2220

return ENXIO;

1797

2221

}

1798

2222

if(interface_is_up(interface)){

1799

error_t ret_errno = 0, ioctl_errno = 0;

2223

int ret_errno = 0;

2224

int ioctl_errno = 0;

1800

2225

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

1801

2226

ret_errno = errno;

1802

2227

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

1822

2247

/* Raise privileges */

1823

2248

ret_errno = raise_privileges();

1824

2249

if(ret_errno != 0){

2250

errno = ret_errno;

1825

2251

perror_plus("Failed to raise privileges");

1826

2252

}

2253

1827

2254

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

1828

2255

ioctl_errno = errno;

1829

2256

1838

2265

}

1839

2266

1840

2267

/* Close the socket */

1841

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

2268

int ret = close(sd);

1842

2269

if(ret == -1){

1843

2270

perror_plus("close");

1844

2271

}

1859

2286

}

1860

2287

1861

2288

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

1862

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

1863

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

1864

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

1865

.interfaces = NULL, .interfaces_size = 0 };

2289

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

2290

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

2291

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

2292

.current_server = NULL, .interfaces = NULL,

2293

.interfaces_size = 0 };

1866

2294

AvahiSServiceBrowser *sb = NULL;

1867

2295

error_t ret_errno;

1868

2296

int ret;

1871

2299

int exitcode = EXIT_SUCCESS;

1872

2300

char *interfaces_to_take_down = NULL;

1873

2301

size_t interfaces_to_take_down_size = 0;

1874

char tempdir[] = "/tmp/mandosXXXXXX";

1875

bool tempdir_created = false;

2302

char run_tempdir[] = "/run/tmp/mandosXXXXXX";

2303

char old_tempdir[] = "/tmp/mandosXXXXXX";

2304

char *tempdir = NULL;

1876

2305

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1877

2306

const char *seckey = PATHDIR "/" SECKEY;

1878

2307

const char *pubkey = PATHDIR "/" PUBKEY;

2308

const char *dh_params_file = NULL;

1879

2309

char *interfaces_hooks = NULL;

1880

2310

1881

2311

bool gnutls_initialized = false;

1934

2364

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

1935

2365

" Diffie-Hellman key exchange",

1936

2366

.group = 2 },

2367

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

2368

.arg = "FILE",

2369

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

2370

" for the Diffie-Hellman key exchange",

2371

.group = 2 },

1937

2372

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

1938

2373

.arg = "STRING",

1939

2374

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

1994

2429

}

1995

2430

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

1996

2431

break;

2432

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

2433

dh_params_file = arg;

2434

break;

1997

2435

case 130: /* --priority */

1998

2436

mc.priority = arg;

1999

2437

break;

2039

2477

.args_doc = "",

2040

2478

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

2041

2479

" passwords from a Mandos server" };

2042

ret = argp_parse(&argp, argc, argv,

2043

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2044

switch(ret){

2480

ret_errno = argp_parse(&argp, argc, argv,

2481

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2482

switch(ret_errno){

2045

2483

case 0:

2046

2484

break;

2047

2485

case ENOMEM:

2048

2486

default:

2049

errno = ret;

2487

errno = ret_errno;

2050

2488

perror_plus("argp_parse");

2051

2489

exitcode = EX_OSERR;

2052

2490

goto end;

2055

2493

goto end;

2056

2494

}

2057

2495

}

2058

2496

2059

2497

{

2060

2498

/* Work around Debian bug #633582:

2061

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

2499

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

2062

2500

2063

2501

/* Re-raise privileges */

2064

ret_errno = raise_privileges();

2065

if(ret_errno != 0){

2066

errno = ret_errno;

2502

ret = raise_privileges();

2503

if(ret != 0){

2504

errno = ret;

2067

2505

perror_plus("Failed to raise privileges");

2068

2506

} else {

2069

2507

struct stat st;

2085

2523

}

2086

2524

}

2087

2525

}

2088

TEMP_FAILURE_RETRY(close(seckey_fd));

2526

close(seckey_fd);

2089

2527

}

2090

2528

}

2091

2529

2092

2530

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

2093

2531

int pubkey_fd = open(pubkey, O_RDONLY);

2094

2532

if(pubkey_fd == -1){

2106

2544

}

2107

2545

}

2108

2546

}

2109

TEMP_FAILURE_RETRY(close(pubkey_fd));

2110

}

2111

}

2112

2547

close(pubkey_fd);

2548

}

2549

}

2550

2551

if(dh_params_file != NULL

2552

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

2553

int dhparams_fd = open(dh_params_file, O_RDONLY);

2554

if(dhparams_fd == -1){

2555

perror_plus("open");

2556

} else {

2557

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

2558

if(ret == -1){

2559

perror_plus("fstat");

2560

} else {

2561

if(S_ISREG(st.st_mode)

2562

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

2563

ret = fchown(dhparams_fd, uid, gid);

2564

if(ret == -1){

2565

perror_plus("fchown");

2566

}

2567

}

2568

}

2569

close(dhparams_fd);

2570

}

2571

}

2572

2113

2573

/* Lower privileges */

2114

ret_errno = lower_privileges();

2115

if(ret_errno != 0){

2116

errno = ret_errno;

2574

ret = lower_privileges();

2575

if(ret != 0){

2576

errno = ret;

2117

2577

perror_plus("Failed to lower privileges");

2118

2578

}

2119

2579

}

2232

2692

2233

2693

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

2234

2694

if(mc.interfaces == NULL){

2235

struct dirent **direntries;

2695

struct dirent **direntries = NULL;

2236

2696

/* Look for any good interfaces */

2237

2697

ret = scandir(sys_class_net, &direntries, good_interface,

2238

2698

alphasort);

2244

2704

if(ret_errno != 0){

2245

2705

errno = ret_errno;

2246

2706

perror_plus("argz_add");

2707

free(direntries[i]);

2247

2708

continue;

2248

2709

}

2249

2710

if(debug){

2250

2711

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

2251

2712

direntries[i]->d_name);

2252

2713

}

2714

free(direntries[i]);

2253

2715

}

2254

2716

free(direntries);

2255

2717

} else {

2256

free(direntries);

2718

if(ret == 0){

2719

free(direntries);

2720

}

2257

2721

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

2258

2722

exitcode = EXIT_FAILURE;

2259

2723

goto end;

2285

2749

errno = bring_up_interface(interface, delay);

2286

2750

if(not interface_was_up){

2287

2751

if(errno != 0){

2288

perror_plus("Failed to bring up interface");

2752

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

2753

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

2289

2754

} else {

2290

2755

errno = argz_add(&interfaces_to_take_down,

2291

2756

&interfaces_to_take_down_size,

2314

2779

goto end;

2315

2780

}

2316

2781

2317

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

2782

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

2318

2783

if(ret == -1){

2319

2784

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

2320

2785

exitcode = EX_UNAVAILABLE;

2327

2792

goto end;

2328

2793

}

2329

2794

2330

if(mkdtemp(tempdir) == NULL){

2795

/* Try /run/tmp before /tmp */

2796

tempdir = mkdtemp(run_tempdir);

2797

if(tempdir == NULL and errno == ENOENT){

2798

if(debug){

2799

fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",

2800

run_tempdir, old_tempdir);

2801

}

2802

tempdir = mkdtemp(old_tempdir);

2803

}

2804

if(tempdir == NULL){

2331

2805

perror_plus("mkdtemp");

2332

2806

goto end;

2333

2807

}

2334

tempdir_created = true;

2335

2808

2336

2809

if(quit_now){

2337

2810

goto end;

2434

2907

2435

2908

/* Allocate a new server */

2436

2909

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2437

&config, NULL, NULL, &ret_errno);

2910

&config, NULL, NULL, &ret);

2438

2911

2439

2912

/* Free the Avahi configuration data */

2440

2913

avahi_server_config_free(&config);

2443

2916

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

2444

2917

if(mc.server == NULL){

2445

2918

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

2446

avahi_strerror(ret_errno));

2919

avahi_strerror(ret));

2447

2920

exitcode = EX_UNAVAILABLE;

2448

2921

goto end;

2449

2922

}

2473

2946

if(debug){

2474

2947

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

2475

2948

}

2476

2949

2477

2950

ret = avahi_loop_with_timeout(simple_poll,

2478

2951

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

2479

2952

if(debug){

2501

2974

2502

2975

if(gnutls_initialized){

2503

2976

gnutls_certificate_free_credentials(mc.cred);

2504

gnutls_global_deinit();

2505

2977

gnutls_dh_params_deinit(mc.dh_params);

2506

2978

}

2507

2979

2515

2987

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

2516

2988

while(mc.current_server != NULL){

2517

2989

server *next = mc.current_server->next;

2990

#ifdef __GNUC__

2991

#pragma GCC diagnostic push

2992

#pragma GCC diagnostic ignored "-Wcast-qual"

2993

#endif

2994

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

2995

#ifdef __GNUC__

2996

#pragma GCC diagnostic pop

2997

#endif

2518

2998

free(mc.current_server);

2519

2999

mc.current_server = next;

2520

3000

}

2522

3002

2523

3003

/* Re-raise privileges */

2524

3004

{

2525

ret_errno = raise_privileges();

2526

if(ret_errno != 0){

3005

ret = raise_privileges();

3006

if(ret != 0){

3007

errno = ret;

2527

3008

perror_plus("Failed to raise privileges");

2528

3009

} else {

2529

3010

2537

3018

while((interface=argz_next(interfaces_to_take_down,

2538

3019

interfaces_to_take_down_size,

2539

3020

interface))){

2540

ret_errno = take_down_interface(interface);

2541

if(ret_errno != 0){

2542

errno = ret_errno;

3021

ret = take_down_interface(interface);

3022

if(ret != 0){

3023

errno = ret;

2543

3024

perror_plus("Failed to take down interface");

2544

3025

}

2545

3026

}

2549

3030

}

2550

3031

}

2551

3032

}

2552

ret_errno = lower_privileges_permanently();

2553

if(ret_errno != 0){

3033

3034

ret = lower_privileges_permanently();

3035

if(ret != 0){

3036

errno = ret;

2554

3037

perror_plus("Failed to lower privileges permanently");

2555

3038

}

2556

3039

}

2558

3041

free(interfaces_to_take_down);

2559

3042

free(interfaces_hooks);

2560

3043

3044

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

3045

uintmax_t level){

3046

struct dirent **direntries = NULL;

3047

int dret;

3048

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

3049

O_RDONLY

3050

| O_NOFOLLOW

3051

| O_DIRECTORY

3052

| O_PATH));

3053

if(dir_fd == -1){

3054

perror_plus("open");

3055

}

3056

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

3057

notdotentries, alphasort);

3058

if(numentries >= 0){

3059

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

3060

if(debug){

3061

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

3062

dirname, direntries[i]->d_name);

3063

}

3064

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

3065

if(dret == -1){

3066

if(errno == EISDIR){

3067

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

3068

AT_REMOVEDIR);

3069

}

3070

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

3071

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

3072

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

3073

/* Recurse only in this special case */

3074

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

3075

dret = 0;

3076

}

3077

if(dret == -1){

3078

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

3079

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

3080

}

3081

}

3082

free(direntries[i]);

3083

}

3084

3085

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

3086

free(direntries);

3087

if(numentries == -1){

3088

perror_plus("scandirat");

3089

}

3090

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3091

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

3092

perror_plus("rmdir");

3093

}

3094

} else {

3095

perror_plus("scandirat");

3096

}

3097

close(dir_fd);

3098

}

3099

2561

3100

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

2562

if(tempdir_created){

2563

struct dirent **direntries = NULL;

2564

struct dirent *direntry = NULL;

2565

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

2566

alphasort);

2567

if(numentries > 0){

2568

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

2569

direntry = direntries[i];

2570

char *fullname = NULL;

2571

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

2572

direntry->d_name);

2573

if(ret < 0){

2574

perror_plus("asprintf");

2575

continue;

2576

}

2577

ret = remove(fullname);

2578

if(ret == -1){

2579

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

2580

strerror(errno));

2581

}

2582

free(fullname);

2583

}

2584

}

2585

2586

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

2587

free(direntries);

2588

if(numentries == -1){

2589

perror_plus("scandir");

2590

}

2591

ret = rmdir(tempdir);

2592

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

2593

perror_plus("rmdir");

2594

}

3101

if(tempdir != NULL){

3102

clean_dir_at(-1, tempdir, 0);

2595

3103

}

2596

3104

2597

3105

if(quit_now){