/mandos/trunk : revision 702

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

46

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

47

strtof(), abort() */

48

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

49

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

50

asprintf(), strcpy() */

49

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

50

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

51

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

52

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

53

sockaddr_in6, PF_INET6,

234

.af = af };

235

if(new_server->ip == NULL){

236

perror_plus("strdup");

237

free(new_server);

238

237

return false;

239

238

}

240

239

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

241

240

if(ret == -1){

242

241

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

242

return false;

253

243

}

254

244

/* Special case of first server */

305

295

return false;

306

296

}

307

297

308

ret = close(fd);

298

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

309

299

if(ret == -1){

310

300

perror_plus("close");

311

301

}

493

483

return plaintext_length;

494

484

}

495

485

496

__attribute__((warn_unused_result, const))

497

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

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

486

__attribute__((warn_unused_result))

504

487

static const char *safer_gnutls_strerror(int value){

505

488

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

489

if(ret == NULL)

490

ret = "(unknown)";

491

return ret;

507

492

}

508

493

509

494

/* GnuTLS log function callback */

516

501

__attribute__((nonnull, warn_unused_result))

517

502

static int init_gnutls_global(const char *pubkeyfilename,

518

503

const char *seckeyfilename,

519

const char *dhparamsfilename,

520

504

mandos_context *mc){

521

505

int ret;

522

unsigned int uret;

523

506

524

507

if(debug){

525

508

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

576

559

safer_gnutls_strerror(ret));

577

560

goto globalfail;

578

561

}

579

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

580

if(dhparamsfilename != NULL){

581

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

582

do {

583

int dhpfile = open(dhparamsfilename, O_RDONLY);

584

if(dhpfile == -1){

585

perror_plus("open");

586

dhparamsfilename = NULL;

587

break;

588

}

589

size_t params_capacity = 0;

590

while(true){

591

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

592

(size_t)params.size,

593

(size_t)params_capacity);

594

if(params_capacity == 0){

595

perror_plus("incbuffer");

596

free(params.data);

597

params.data = NULL;

598

dhparamsfilename = NULL;

599

break;

600

}

601

ssize_t bytes_read = read(dhpfile,

602

params.data + params.size,

603

BUFFER_SIZE);

604

/* EOF */

605

if(bytes_read == 0){

606

break;

607

}

608

/* check bytes_read for failure */

609

if(bytes_read < 0){

610

perror_plus("read");

611

free(params.data);

612

params.data = NULL;

613

dhparamsfilename = NULL;

614

break;

615

}

616

params.size += (unsigned int)bytes_read;

617

}

618

if(params.data == NULL){

619

dhparamsfilename = NULL;

620

}

621

if(dhparamsfilename == NULL){

622

break;

623

}

624

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

625

GNUTLS_X509_FMT_PEM);

626

if(ret != GNUTLS_E_SUCCESS){

627

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

628

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

629

safer_gnutls_strerror(ret));

630

dhparamsfilename = NULL;

631

}

632

} while(false);

633

}

634

if(dhparamsfilename == NULL){

635

if(mc->dh_bits == 0){

636

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

637

/* Try to read the private key file */

638

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

639

do {

640

int secfile = open(seckeyfilename, O_RDONLY);

641

if(secfile == -1){

642

perror_plus("open");

643

break;

644

}

645

size_t buffer_capacity = 0;

646

while(true){

647

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

648

(size_t)buffer.size,

649

(size_t)buffer_capacity);

650

if(buffer_capacity == 0){

651

perror_plus("incbuffer");

652

free(buffer.data);

653

buffer.data = NULL;

654

break;

655

}

656

ssize_t bytes_read = read(secfile,

657

buffer.data + buffer.size,

658

BUFFER_SIZE);

659

/* EOF */

660

if(bytes_read == 0){

661

break;

662

}

663

/* check bytes_read for failure */

664

if(bytes_read < 0){

665

perror_plus("read");

666

free(buffer.data);

667

buffer.data = NULL;

668

break;

669

}

670

buffer.size += (unsigned int)bytes_read;

671

}

672

close(secfile);

673

} while(false);

674

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

675

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

676

if(buffer.data != NULL){

677

{

678

gnutls_openpgp_privkey_t privkey = NULL;

679

ret = gnutls_openpgp_privkey_init(&privkey);

680

if(ret != GNUTLS_E_SUCCESS){

681

fprintf_plus(stderr, "Error initializing OpenPGP key"

682

" structure: %s",

683

safer_gnutls_strerror(ret));

684

free(buffer.data);

685

buffer.data = NULL;

686

} else {

687

ret = gnutls_openpgp_privkey_import

688

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

689

if(ret != GNUTLS_E_SUCCESS){

690

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

691

safer_gnutls_strerror(ret));

692

privkey = NULL;

693

}

694

free(buffer.data);

695

buffer.data = NULL;

696

if(privkey != NULL){

697

/* Use private key to suggest an appropriate

698

sec_param */

699

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

700

gnutls_openpgp_privkey_deinit(privkey);

701

if(debug){

702

fprintf_plus(stderr, "This OpenPGP key implies using"

703

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

704

safe_string(gnutls_sec_param_get_name

705

(sec_param)));

706

}

707

}

708

}

709

}

710

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

711

/* Err on the side of caution */

712

sec_param = GNUTLS_SEC_PARAM_ULTRA;

713

if(debug){

714

fprintf_plus(stderr, "Falling back to security parameter"

715

" \"%s\"\n",

716

safe_string(gnutls_sec_param_get_name

717

(sec_param)));

718

}

719

}

720

}

721

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

722

if(uret != 0){

723

mc->dh_bits = uret;

724

if(debug){

725

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

726

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

727

safe_string(gnutls_sec_param_get_name

728

(sec_param)),

729

mc->dh_bits);

730

}

731

} else {

732

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

733

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

734

safe_string(gnutls_sec_param_get_name

735

(sec_param)),

736

safer_gnutls_strerror(ret));

737

goto globalfail;

738

}

739

} else if(debug){

740

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

741

mc->dh_bits);

742

}

743

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

744

if(ret != GNUTLS_E_SUCCESS){

745

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

746

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

747

safer_gnutls_strerror(ret));

748

goto globalfail;

749

}

750

}

562

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

563

if(ret != GNUTLS_E_SUCCESS){

564

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

565

safer_gnutls_strerror(ret));

566

goto globalfail;

567

}

568

751

569

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

752

570

753

571

return 0;

813

631

/* ignore client certificate if any. */

814

632

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

815

633

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

635

816

636

return 0;

817

637

}

818

638

820

640

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

821

641

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

822

642

823

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

824

__attribute__((warn_unused_result))

825

error_t raise_privileges(void){

826

error_t old_errno = errno;

827

error_t ret_errno = 0;

828

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

829

ret_errno = errno;

830

}

831

errno = old_errno;

832

return ret_errno;

833

}

834

835

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

836

__attribute__((warn_unused_result))

837

error_t raise_privileges_permanently(void){

838

error_t old_errno = errno;

839

error_t ret_errno = raise_privileges();

840

if(ret_errno != 0){

841

errno = old_errno;

842

return ret_errno;

843

}

844

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

845

ret_errno = errno;

846

}

847

errno = old_errno;

848

return ret_errno;

849

}

850

851

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

852

__attribute__((warn_unused_result))

853

error_t lower_privileges(void){

854

error_t old_errno = errno;

855

error_t ret_errno = 0;

856

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

857

ret_errno = errno;

858

}

859

errno = old_errno;

860

return ret_errno;

861

}

862

863

/* Lower privileges permanently */

864

__attribute__((warn_unused_result))

865

error_t lower_privileges_permanently(void){

866

error_t old_errno = errno;

867

error_t ret_errno = 0;

868

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

869

ret_errno = errno;

870

}

871

errno = old_errno;

872

return ret_errno;

873

}

874

875

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

876

__attribute__((nonnull, warn_unused_result))

877

static bool add_delete_local_route(const bool add,

878

const char *address,

879

AvahiIfIndex if_index){

880

int ret;

881

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

882

char add_arg[] = "add";

883

char delete_arg[] = "delete";

884

char debug_flag[] = "--debug";

885

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

886

if(pluginhelperdir == NULL){

887

if(debug){

888

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

889

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

890

}

891

return false;

892

}

893

894

char interface[IF_NAMESIZE];

895

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

896

perror_plus("if_indextoname");

897

return false;

898

}

899

900

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

901

if(devnull == -1){

902

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

903

return false;

904

}

905

pid_t pid = fork();

906

if(pid == 0){

907

/* Child */

908

/* Raise privileges */

909

errno = raise_privileges_permanently();

910

if(errno != 0){

911

perror_plus("Failed to raise privileges");

912

/* _exit(EX_NOPERM); */

913

} else {

914

/* Set group */

915

errno = 0;

916

ret = setgid(0);

917

if(ret == -1){

918

perror_plus("setgid");

919

_exit(EX_NOPERM);

920

}

921

/* Reset supplementary groups */

922

errno = 0;

923

ret = setgroups(0, NULL);

924

if(ret == -1){

925

perror_plus("setgroups");

926

_exit(EX_NOPERM);

927

}

928

}

929

ret = dup2(devnull, STDIN_FILENO);

930

if(ret == -1){

931

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

932

_exit(EX_OSERR);

933

}

934

ret = close(devnull);

935

if(ret == -1){

936

perror_plus("close");

937

_exit(EX_OSERR);

938

}

939

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

940

if(ret == -1){

941

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

942

_exit(EX_OSERR);

943

}

944

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

945

O_RDONLY

946

| O_DIRECTORY

947

| O_PATH

948

| O_CLOEXEC));

949

if(helperdir_fd == -1){

950

perror_plus("open");

951

_exit(EX_UNAVAILABLE);

952

}

953

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

954

helper, O_RDONLY));

955

if(helper_fd == -1){

956

perror_plus("openat");

957

_exit(EX_UNAVAILABLE);

958

}

959

close(helperdir_fd);

960

#ifdef __GNUC__

961

#pragma GCC diagnostic push

962

#pragma GCC diagnostic ignored "-Wcast-qual"

963

#endif

964

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

965

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

966

interface, debug ? debug_flag : NULL, NULL },

967

environ) == -1){

968

#ifdef __GNUC__

969

#pragma GCC diagnostic pop

970

#endif

971

perror_plus("fexecve");

972

_exit(EXIT_FAILURE);

973

}

974

}

975

if(pid == -1){

976

perror_plus("fork");

977

return false;

978

}

979

int status;

980

pid_t pret = -1;

981

errno = 0;

982

do {

983

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

984

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

985

int errno_raising = 0;

986

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

987

errno_raising = errno;

988

perror_plus("Failed to raise privileges in order to"

989

" kill helper program");

990

}

991

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

992

perror_plus("kill");

993

}

994

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

995

perror_plus("Failed to lower privileges after killing"

996

" helper program");

997

}

998

return false;

999

}

1000

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

1001

if(pret == -1){

1002

perror_plus("waitpid");

1003

return false;

1004

}

1005

if(WIFEXITED(status)){

1006

if(WEXITSTATUS(status) != 0){

1007

fprintf_plus(stderr, "Error: iprouteadddel exited"

1008

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

1009

return false;

1010

}

1011

return true;

1012

}

1013

if(WIFSIGNALED(status)){

1014

fprintf_plus(stderr, "Error: iprouteadddel died by"

1015

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

1016

return false;

1017

}

1018

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

1019

return false;

1020

}

1021

1022

__attribute__((nonnull, warn_unused_result))

1023

static bool add_local_route(const char *address,

1024

AvahiIfIndex if_index){

1025

if(debug){

1026

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

1027

}

1028

return add_delete_local_route(true, address, if_index);

1029

}

1030

1031

__attribute__((nonnull, warn_unused_result))

1032

static bool delete_local_route(const char *address,

1033

AvahiIfIndex if_index){

1034

if(debug){

1035

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

1036

}

1037

return add_delete_local_route(false, address, if_index);

1038

}

1039

1040

643

/* Called when a Mandos server is found */

1041

644

__attribute__((nonnull, warn_unused_result))

1042

645

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

1053

656

int retval = -1;

1054

657

gnutls_session_t session;

1055

658

int pf; /* Protocol family */

1056

bool route_added = false;

1057

659

1058

660

errno = 0;

1059

661

1117

719

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

1118

720

}

1119

721

1120

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

722

tcp_sd = socket(pf, SOCK_STREAM, 0);

1121

723

if(tcp_sd < 0){

1122

724

int e = errno;

1123

725

perror_plus("socket");

1130

732

goto mandos_end;

1131

733

}

1132

734

735

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

1133

736

if(af == AF_INET6){

1134

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

1135

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

1136

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

737

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

738

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

1137

739

} else { /* IPv4 */

1138

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

1139

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

1140

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

740

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

741

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

1141

742

}

1142

743

if(ret < 0 ){

1143

744

int e = errno;

1213

814

goto mandos_end;

1214

815

}

1215

816

1216

while(true){

1217

if(af == AF_INET6){

1218

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

1219

sizeof(struct sockaddr_in6));

1220

} else {

1221

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

1222

sizeof(struct sockaddr_in));

1223

}

1224

if(ret < 0){

1225

if(errno == ENETUNREACH

1226

and if_index != AVAHI_IF_UNSPEC

1227

and connect_to == NULL

1228

and not route_added and

1229

((af == AF_INET6 and not

1230

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1231

&to)->sin6_addr)))

1232

or (af == AF_INET and

1233

/* Not a a IPv4LL address */

1234

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

1235

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

1236

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

1237

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

1238

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

1239

connect to a Mandos server announced by Avahi on a server

1240

host with a global address. Work around this by retrying

1241

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

1242

1243

Avahi bug reference:

1244

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

1245

https://bugs.debian.org/587961

1246

*/

1247

if(debug){

1248

fprintf_plus(stderr, "Mandos server unreachable, trying"

1249

" direct route\n");

1250

}

1251

int e = errno;

1252

route_added = add_local_route(ip, if_index);

1253

if(route_added){

1254

continue;

1255

}

1256

errno = e;

1257

}

1258

if(errno != ECONNREFUSED or debug){

1259

int e = errno;

1260

perror_plus("connect");

1261

errno = e;

1262

}

1263

goto mandos_end;

1264

}

1265

1266

if(quit_now){

1267

errno = EINTR;

1268

goto mandos_end;

1269

}

1270

break;

817

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

820

} else {

821

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

822

sizeof(struct sockaddr_in));

823

}

824

if(ret < 0){

825

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

826

int e = errno;

827

perror_plus("connect");

828

errno = e;

829

}

830

goto mandos_end;

831

}

832

833

if(quit_now){

834

errno = EINTR;

835

goto mandos_end;

1271

836

}

1272

837

1273

838

const char *out = mandos_protocol_version;

1456

1021

1457

1022

mandos_end:

1458

1023

{

1459

if(route_added){

1460

if(not delete_local_route(ip, if_index)){

1461

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

1462

" interface %d", ip, if_index);

1463

}

1464

}

1465

1024

int e = errno;

1466

1025

free(decrypted_buffer);

1467

1026

free(buffer);

1468

1027

if(tcp_sd >= 0){

1469

ret = close(tcp_sd);

1028

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

1470

1029

}

1471

1030

if(ret == -1){

1472

1031

if(e == 0){

1507

1066

timed out */

1508

1067

1509

1068

if(quit_now){

1510

avahi_s_service_resolver_free(r);

1511

1069

return;

1512

1070

}

1513

1071

1893

1451

}

1894

1452

}

1895

1453

1454

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

1455

__attribute__((warn_unused_result))

1456

error_t raise_privileges(void){

1457

error_t old_errno = errno;

1458

error_t ret_errno = 0;

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

__attribute__((warn_unused_result))

1469

error_t raise_privileges_permanently(void){

1470

error_t old_errno = errno;

1471

error_t ret_errno = raise_privileges();

1472

if(ret_errno != 0){

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

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

1477

ret_errno = errno;

1478

perror_plus("seteuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

__attribute__((warn_unused_result))

1486

error_t lower_privileges(void){

1487

error_t old_errno = errno;

1488

error_t ret_errno = 0;

1489

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

1490

ret_errno = errno;

1491

perror_plus("seteuid");

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

error_t lower_privileges_permanently(void){

1500

error_t old_errno = errno;

1501

error_t ret_errno = 0;

1502

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

1503

ret_errno = errno;

1504

perror_plus("setuid");

1505

}

1506

errno = old_errno;

1507

return ret_errno;

1508

}

1509

1896

1510

__attribute__((nonnull))

1897

1511

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

1898

1512

const float delay){

1899

struct dirent **direntries = NULL;

1513

struct dirent **direntries;

1900

1514

if(hookdir_fd == -1){

1901

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1902

| O_CLOEXEC);

1515

hookdir_fd = open(hookdir, O_RDONLY);

1903

1516

if(hookdir_fd == -1){

1904

1517

if(errno == ENOENT){

1905

1518

if(debug){

1930

1543

}

1931

1544

struct dirent *direntry;

1932

1545

int ret;

1933

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

1934

if(devnull == -1){

1935

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

1936

return;

1937

}

1546

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

1938

1547

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

1939

1548

direntry = direntries[i];

1940

1549

if(debug){

1945

1554

if(hook_pid == 0){

1946

1555

/* Child */

1947

1556

/* Raise privileges */

1948

errno = raise_privileges_permanently();

1949

if(errno != 0){

1557

if(raise_privileges_permanently() != 0){

1950

1558

perror_plus("Failed to raise privileges");

1951

1559

_exit(EX_NOPERM);

1952

1560

}

1964

1572

perror_plus("setgroups");

1965

1573

_exit(EX_NOPERM);

1966

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1967

1590

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

1968

1591

if(ret == -1){

1969

1592

perror_plus("setenv");

2004

1627

_exit(EX_OSERR);

2005

1628

}

2006

1629

}

2007

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

2008

direntry->d_name,

2009

O_RDONLY));

1630

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

2010

1631

if(hook_fd == -1){

2011

1632

perror_plus("openat");

2012

1633

_exit(EXIT_FAILURE);

2013

1634

}

2014

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

1635

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

2015

1636

perror_plus("close");

2016

1637

_exit(EXIT_FAILURE);

2017

1638

}

2018

ret = dup2(devnull, STDIN_FILENO);

2019

if(ret == -1){

2020

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

2021

_exit(EX_OSERR);

2022

}

2023

ret = close(devnull);

2024

if(ret == -1){

2025

perror_plus("close");

2026

_exit(EX_OSERR);

2027

}

2028

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2029

if(ret == -1){

2030

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

2031

_exit(EX_OSERR);

2032

}

2033

1639

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

2034

1640

environ) == -1){

2035

1641

perror_plus("fexecve");

2036

1642

_exit(EXIT_FAILURE);

2037

1643

}

2038

1644

} else {

2039

if(hook_pid == -1){

2040

perror_plus("fork");

2041

free(direntry);

2042

continue;

2043

}

2044

1645

int status;

2045

1646

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

2046

1647

perror_plus("waitpid");

2047

free(direntry);

2048

1648

continue;

2049

1649

}

2050

1650

if(WIFEXITED(status)){

2052

1652

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

2053

1653

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

2054

1654

WEXITSTATUS(status));

2055

free(direntry);

2056

1655

continue;

2057

1656

}

2058

1657

} else if(WIFSIGNALED(status)){

2059

1658

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

2060

1659

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

2061

1660

WTERMSIG(status));

2062

free(direntry);

2063

1661

continue;

2064

1662

} else {

2065

1663

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

2066

1664

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

2067

free(direntry);

2068

1665

continue;

2069

1666

}

2070

1667

}

2072

1669

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

2073

1670

direntry->d_name);

2074

1671

}

2075

free(direntry);

2076

1672

}

2077

free(direntries);

2078

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

1673

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

2079

1674

perror_plus("close");

2080

1675

} else {

2081

1676

hookdir_fd = -1;

2121

1716

}

2122

1717

2123

1718

if(quit_now){

2124

ret = close(sd);

1719

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

2125

1720

if(ret == -1){

2126

1721

perror_plus("close");

2127

1722

}

2137

1732

/* Raise privileges */

2138

1733

ret_errno = raise_privileges();

2139

1734

if(ret_errno != 0){

2140

errno = ret_errno;

2141

1735

perror_plus("Failed to raise privileges");

2142

1736

}

2143

1737

2177

1771

}

2178

1772

2179

1773

/* Close the socket */

2180

ret = close(sd);

1774

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

2181

1775

if(ret == -1){

2182

1776

perror_plus("close");

2183

1777

}

2247

1841

/* Raise privileges */

2248

1842

ret_errno = raise_privileges();

2249

1843

if(ret_errno != 0){

2250

errno = ret_errno;

2251

1844

perror_plus("Failed to raise privileges");

2252

1845

}

2253

1846

2265

1858

}

2266

1859

2267

1860

/* Close the socket */

2268

int ret = close(sd);

1861

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

2269

1862

if(ret == -1){

2270

1863

perror_plus("close");

2271

1864

}

2286

1879

}

2287

1880

2288

1881

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

2289

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

1882

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

2290

1883

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

2291

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

1884

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

2292

1885

.interfaces = NULL, .interfaces_size = 0 };

2293

1886

AvahiSServiceBrowser *sb = NULL;

2294

1887

error_t ret_errno;

2304

1897

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2305

1898

const char *seckey = PATHDIR "/" SECKEY;

2306

1899

const char *pubkey = PATHDIR "/" PUBKEY;

2307

const char *dh_params_file = NULL;

2308

1900

char *interfaces_hooks = NULL;

2309

1901

2310

1902

bool gnutls_initialized = false;

2363

1955

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

2364

1956

" Diffie-Hellman key exchange",

2365

1957

.group = 2 },

2366

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

2367

.arg = "FILE",

2368

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

2369

" for the Diffie-Hellman key exchange",

2370

.group = 2 },

2371

1958

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

2372

1959

.arg = "STRING",

2373

1960

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

2428

2015

}

2429

2016

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

2430

2017

break;

2431

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

2432

dh_params_file = arg;

2433

break;

2434

2018

case 130: /* --priority */

2435

2019

mc.priority = arg;

2436

2020

break;

2492

2076

goto end;

2493

2077

}

2494

2078

}

2495

2079

2496

2080

{

2497

2081

/* Work around Debian bug #633582:

2498

2082

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

2522

2106

}

2523

2107

}

2524

2108

}

2525

close(seckey_fd);

2109

TEMP_FAILURE_RETRY(close(seckey_fd));

2526

2110

}

2527

2111

}

2528

2112

2529

2113

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

2530

2114

int pubkey_fd = open(pubkey, O_RDONLY);

2531

2115

if(pubkey_fd == -1){

2543

2127

}

2544

2128

}

2545

2129

}

2546

close(pubkey_fd);

2547

}

2548

}

2549

2550

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

2551

int dhparams_fd = open(dh_params_file, O_RDONLY);

2552

if(dhparams_fd == -1){

2553

perror_plus("open");

2554

} else {

2555

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

2556

if(ret == -1){

2557

perror_plus("fstat");

2558

} else {

2559

if(S_ISREG(st.st_mode)

2560

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

2561

ret = fchown(dhparams_fd, uid, gid);

2562

if(ret == -1){

2563

perror_plus("fchown");

2564

}

2565

}

2566

}

2567

close(dhparams_fd);

2568

}

2569

}

2570

2130

TEMP_FAILURE_RETRY(close(pubkey_fd));

2131

}

2132

}

2133

2571

2134

/* Lower privileges */

2572

2135

ret_errno = lower_privileges();

2573

2136

if(ret_errno != 0){

2702

2265

if(ret_errno != 0){

2703

2266

errno = ret_errno;

2704

2267

perror_plus("argz_add");

2705

free(direntries[i]);

2706

2268

continue;

2707

2269

}

2708

2270

if(debug){

2709

2271

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

2710

2272

direntries[i]->d_name);

2711

2273

}

2712

free(direntries[i]);

2713

2274

}

2714

2275

free(direntries);

2715

2276

} else {

2716

if(ret == 0){

2717

free(direntries);

2718

}

2277

free(direntries);

2719

2278

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

2720

2279

exitcode = EXIT_FAILURE;

2721

2280

goto end;

2747

2306

errno = bring_up_interface(interface, delay);

2748

2307

if(not interface_was_up){

2749

2308

if(errno != 0){

2750

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

2751

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

2309

perror_plus("Failed to bring up interface");

2752

2310

} else {

2753

2311

errno = argz_add(&interfaces_to_take_down,

2754

2312

&interfaces_to_take_down_size,

2777

2335

goto end;

2778

2336

}

2779

2337

2780

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

2338

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

2781

2339

if(ret == -1){

2782

2340

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

2783

2341

exitcode = EX_UNAVAILABLE;

2986

2544

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

2987

2545

while(mc.current_server != NULL){

2988

2546

server *next = mc.current_server->next;

2989

#ifdef __GNUC__

2990

#pragma GCC diagnostic push

2991

#pragma GCC diagnostic ignored "-Wcast-qual"

2992

#endif

2993

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

2994

#ifdef __GNUC__

2995

#pragma GCC diagnostic pop

2996

#endif

2997

2547

free(mc.current_server);

2998

2548

mc.current_server = next;

2999

2549

}

3003

2553

{

3004

2554

ret_errno = raise_privileges();

3005

2555

if(ret_errno != 0){

3006

errno = ret_errno;

3007

2556

perror_plus("Failed to raise privileges");

3008

2557

} else {

3009

2558

3032

2581

3033

2582

ret_errno = lower_privileges_permanently();

3034

2583

if(ret_errno != 0){

3035

errno = ret_errno;

3036

2584

perror_plus("Failed to lower privileges permanently");

3037

2585

}

3038

2586

}

3043

2591

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

3044

2592

if(tempdir != NULL){

3045

2593

struct dirent **direntries = NULL;

3046

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

3047

| O_NOFOLLOW

3048

| O_DIRECTORY

3049

| O_PATH));

2594

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

2595

O_NOFOLLOW));

3050

2596

if(tempdir_fd == -1){

3051

2597

perror_plus("open");

3052

2598

} else {

3062

2608

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

3063

2609

alphasort);

3064

2610

#endif /* not __GLIBC__ */

3065

if(numentries >= 0){

2611

if(numentries > 0){

3066

2612

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

3067

2613

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

3068

2614

if(ret == -1){

3070

2616

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

3071

2617

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

3072

2618

}

3073

free(direntries[i]);

3074

2619

}

3075

2620

3076

2621

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

3083

2628

perror_plus("rmdir");

3084

2629

}

3085

2630

}

3086

close(tempdir_fd);

2631

TEMP_FAILURE_RETRY(close(tempdir_fd));

3087

2632

}

3088

2633

}

3089

2634