/mandos/trunk : revision 738.1.4

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(),

55

opendir(), DIR */

56

#include <sys/stat.h> /* open(), S_ISREG */

57

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

58

inet_pton(), connect() */

59

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

60

61

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

61

62

*/

62

63

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

72

73

*/

73

74

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

74

75

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

75

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

76

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

76

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

77

unlinkat() */

78

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

77

79

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

78

80

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

79

81

argp_state, struct argp,

91

93

argz_delete(), argz_append(),

92

94

argz_stringify(), argz_add(),

93

95

argz_count() */

96

#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,

97

EAI_SYSTEM, gai_strerror() */

94

98

95

99

#ifdef __linux__

96

100

#include <sys/klog.h> /* klogctl() */

138

142

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

139

143

char *connect_to = NULL;

140

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

141

146

uid_t uid = 65534;

142

147

gid_t gid = 65534;

143

148

180

185

perror(print_text);

181

186

}

182

187

183

__attribute__((format (gnu_printf, 2, 3)))

188

__attribute__((format (gnu_printf, 2, 3), nonnull))

184

189

int fprintf_plus(FILE *stream, const char *format, ...){

185

190

va_list ap;

186

191

va_start (ap, format);

187

192

188

193

TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",

189

194

program_invocation_short_name));

190

return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

195

return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

191

196

}

192

197

193

198

/*

195

200

* bytes. "buffer_capacity" is how much is currently allocated,

196

201

* "buffer_length" is how much is already used.

197

202

*/

203

__attribute__((nonnull, warn_unused_result))

198

204

size_t incbuffer(char **buffer, size_t buffer_length,

199

205

size_t buffer_capacity){

200

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

201

*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

202

if(buffer == NULL){

207

char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

203

213

return 0;

204

214

}

215

*buffer = new_buf;

205

216

buffer_capacity += BUFFER_SIZE;

206

217

}

207

218

return buffer_capacity;

208

219

}

209

220

210

221

/* Add server to set of servers to retry periodically */

222

__attribute__((nonnull, warn_unused_result))

211

223

bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,

212

224

int af, server **current_server){

213

225

int ret;

222

234

.af = af };

223

235

if(new_server->ip == NULL){

224

236

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

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);

225

252

return false;

226

253

}

227

254

/* Special case of first server */

229

256

new_server->next = new_server;

230

257

new_server->prev = new_server;

231

258

*current_server = new_server;

232

/* Place the new server last in the list */

233

259

} else {

260

/* Place the new server last in the list */

234

261

new_server->next = *current_server;

235

262

new_server->prev = (*current_server)->prev;

236

263

new_server->prev->next = new_server;

237

264

(*current_server)->prev = new_server;

238

265

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

266

return true;

245

267

}

246

268

247

269

/*

248

270

* Initialize GPGME.

249

271

*/

250

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

251

const char *tempdir, mandos_context *mc){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

252

277

gpgme_error_t rc;

253

278

gpgme_engine_info_t engine_info;

254

279

255

280

/*

256

281

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

257

282

*/

258

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

259

284

int ret;

260

285

int fd;

261

286

gpgme_data_t pgp_data;

342

367

* Decrypt OpenPGP data.

343

368

* Returns -1 on error

344

369

*/

370

__attribute__((nonnull, warn_unused_result))

345

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

346

372

size_t crypto_size,

347

373

char **plaintext,

467

493

return plaintext_length;

468

494

}

469

495

470

static const char * safer_gnutls_strerror(int value){

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

471

498

const char *ret = gnutls_strerror(value);

472

499

if(ret == NULL)

473

500

ret = "(unknown)";

475

502

}

476

503

477

504

/* GnuTLS log function callback */

505

__attribute__((nonnull))

478

506

static void debuggnutls(__attribute__((unused)) int level,

479

507

const char* string){

480

508

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

481

509

}

482

510

511

__attribute__((nonnull, warn_unused_result))

483

512

static int init_gnutls_global(const char *pubkeyfilename,

484

513

const char *seckeyfilename,

485

514

mandos_context *mc){

559

588

return -1;

560

589

}

561

590

591

__attribute__((nonnull, warn_unused_result))

562

592

static int init_gnutls_session(gnutls_session_t *session,

563

593

mandos_context *mc){

564

594

int ret;

620

650

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

621

651

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

622

652

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char delete_arg[] = "delete";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

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

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

if(helperdir_fd == -1){

779

perror_plus("open");

780

_exit(EX_UNAVAILABLE);

781

}

782

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

783

helper, O_RDONLY));

784

if(helper_fd == -1){

785

perror_plus("openat");

786

_exit(EX_UNAVAILABLE);

787

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

789

#ifdef __GNUC__

790

#pragma GCC diagnostic push

791

#pragma GCC diagnostic ignored "-Wcast-qual"

792

#endif

793

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

794

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

795

interface, NULL }, environ) == -1){

796

#ifdef __GNUC__

797

#pragma GCC diagnostic pop

798

#endif

799

perror_plus("fexecve");

800

_exit(EXIT_FAILURE);

801

}

802

}

803

if(pid == -1){

804

perror_plus("fork");

805

return false;

806

}

807

int status;

808

pid_t pret = -1;

809

errno = 0;

810

do {

811

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

812

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

813

int errno_raising = 0;

814

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

815

errno_raising = errno;

816

perror_plus("Failed to raise privileges in order to"

817

" kill helper program");

818

}

819

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

820

perror_plus("kill");

821

}

822

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

823

perror_plus("Failed to lower privileges after killing"

824

" helper program");

825

}

826

return false;

827

}

828

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

829

if(pret == -1){

830

perror_plus("waitpid");

831

return false;

832

}

833

if(WIFEXITED(status)){

834

if(WEXITSTATUS(status) != 0){

835

fprintf_plus(stderr, "Error: iprouteadddel exited"

836

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

837

return false;

838

}

839

return true;

840

}

841

if(WIFSIGNALED(status)){

842

fprintf_plus(stderr, "Error: iprouteadddel died by"

843

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

844

return false;

845

}

846

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

847

return false;

848

}

849

850

__attribute__((nonnull, warn_unused_result))

851

static bool add_local_route(const char *address,

852

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

854

}

855

856

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

858

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

860

}

861

623

862

/* Called when a Mandos server is found */

863

__attribute__((nonnull, warn_unused_result))

624

864

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

625

865

AvahiIfIndex if_index,

626

866

int af, mandos_context *mc){

627

867

int ret, tcp_sd = -1;

628

868

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

869

struct sockaddr_storage to;

633

870

char *buffer = NULL;

634

871

char *decrypted_buffer = NULL;

635

872

size_t buffer_length = 0;

638

875

int retval = -1;

639

876

gnutls_session_t session;

640

877

int pf; /* Protocol family */

878

bool route_added = false;

641

879

642

880

errno = 0;

643

881

659

897

return -1;

660

898

}

661

899

900

/* If the interface is specified and we have a list of interfaces */

901

if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){

902

/* Check if the interface is one of the interfaces we are using */

903

bool match = false;

904

{

905

char *interface = NULL;

906

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

907

interface))){

908

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

909

match = true;

910

break;

911

}

912

}

913

}

914

if(not match){

915

/* This interface does not match any in the list, so we don't

916

connect to the server */

917

if(debug){

918

char interface[IF_NAMESIZE];

919

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

920

perror_plus("if_indextoname");

921

} else {

922

fprintf_plus(stderr, "Skipping server on non-used interface"

923

" \"%s\"\n",

924

if_indextoname((unsigned int)if_index,

925

interface));

926

}

927

}

928

return -1;

929

}

930

}

931

662

932

ret = init_gnutls_session(&session, mc);

663

933

if(ret != 0){

664

934

return -1;

669

939

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

670

940

}

671

941

672

tcp_sd = socket(pf, SOCK_STREAM, 0);

942

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

673

943

if(tcp_sd < 0){

674

944

int e = errno;

675

945

perror_plus("socket");

684

954

685

955

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

686

956

if(af == AF_INET6){

687

to.in6.sin6_family = (sa_family_t)af;

688

ret = inet_pton(af, ip, &to.in6.sin6_addr);

957

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

958

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

689

959

} else { /* IPv4 */

690

to.in.sin_family = (sa_family_t)af;

691

ret = inet_pton(af, ip, &to.in.sin_addr);

960

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

961

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

692

962

}

693

963

if(ret < 0 ){

694

964

int e = errno;

703

973

goto mandos_end;

704

974

}

705

975

if(af == AF_INET6){

706

to.in6.sin6_port = htons(port);

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

708

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and

709

-Wunreachable-code*/

976

((struct sockaddr_in6 *)&to)->sin6_port = htons(port);

977

if(IN6_IS_ADDR_LINKLOCAL

978

(&((struct sockaddr_in6 *)&to)->sin6_addr)){

710

979

if(if_index == AVAHI_IF_UNSPEC){

711

980

fprintf_plus(stderr, "An IPv6 link-local address is"

712

981

" incomplete without a network interface\n");

714

983

goto mandos_end;

715

984

}

716

985

/* Set the network interface number as scope */

717

to.in6.sin6_scope_id = (uint32_t)if_index;

986

((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;

718

987

}

719

988

} else {

720

to.in.sin_port = htons(port); /* Spurious warnings from

721

-Wconversion and

722

-Wunreachable-code */

989

((struct sockaddr_in *)&to)->sin_port = htons(port);

723

990

}

724

991

725

992

if(quit_now){

742

1009

}

743

1010

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

744

1011

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

745

const char *pcret;

746

if(af == AF_INET6){

747

pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,

748

sizeof(addrstr));

749

} else {

750

pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,

751

sizeof(addrstr));

752

}

753

if(pcret == NULL){

754

perror_plus("inet_ntop");

755

} else {

756

if(strcmp(addrstr, ip) != 0){

757

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

758

}

759

}

760

}

761

762

if(quit_now){

763

errno = EINTR;

764

goto mandos_end;

765

}

766

767

if(af == AF_INET6){

768

ret = connect(tcp_sd, &to.in6, sizeof(to));

769

} else {

770

ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */

771

}

772

if(ret < 0){

773

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

774

int e = errno;

775

perror_plus("connect");

776

errno = e;

777

}

778

goto mandos_end;

779

}

780

781

if(quit_now){

782

errno = EINTR;

783

goto mandos_end;

1012

if(af == AF_INET6){

1013

ret = getnameinfo((struct sockaddr *)&to,

1014

sizeof(struct sockaddr_in6),

1015

addrstr, sizeof(addrstr), NULL, 0,

1016

NI_NUMERICHOST);

1017

} else {

1018

ret = getnameinfo((struct sockaddr *)&to,

1019

sizeof(struct sockaddr_in),

1020

addrstr, sizeof(addrstr), NULL, 0,

1021

NI_NUMERICHOST);

1022

}

1023

if(ret == EAI_SYSTEM){

1024

perror_plus("getnameinfo");

1025

} else if(ret != 0) {

1026

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

1027

} else if(strcmp(addrstr, ip) != 0){

1028

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

1029

}

1030

}

1031

1032

if(quit_now){

1033

errno = EINTR;

1034

goto mandos_end;

1035

}

1036

1037

while(true){

1038

if(af == AF_INET6){

1039

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

1040

sizeof(struct sockaddr_in6));

1041

} else {

1042

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

1043

sizeof(struct sockaddr_in));

1044

}

1045

if(ret < 0){

1046

if(errno == ENETUNREACH

1047

and if_index != AVAHI_IF_UNSPEC

1048

and connect_to == NULL

1049

and not route_added and

1050

((af == AF_INET6 and not

1051

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1052

&to)->sin6_addr)))

1053

or (af == AF_INET and

1054

/* Not a a IPv4LL address */

1055

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

1056

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

1057

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

1058

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

1059

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

1060

connect to a Mandos server announced by Avahi on a server

1061

host with a global address. Work around this by retrying

1062

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

1063

1064

Avahi bug reference:

1065

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

1066

https://bugs.debian.org/587961

1067

*/

1068

int e = errno;

1069

route_added = add_local_route(ip, if_index);

1070

if(route_added){

1071

continue;

1072

}

1073

errno = e;

1074

}

1075

if(errno != ECONNREFUSED or debug){

1076

int e = errno;

1077

perror_plus("connect");

1078

errno = e;

1079

}

1080

goto mandos_end;

1081

}

1082

1083

if(quit_now){

1084

errno = EINTR;

1085

goto mandos_end;

1086

}

1087

break;

784

1088

}

785

1089

786

1090

const char *out = mandos_protocol_version;

969

1273

970

1274

mandos_end:

971

1275

{

1276

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

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

1279

" interface %d", ip, if_index);

1280

}

1281

}

972

1282

int e = errno;

973

1283

free(decrypted_buffer);

974

1284

free(buffer);

991

1301

return retval;

992

1302

}

993

1303

1304

__attribute__((nonnull))

994

1305

static void resolve_callback(AvahiSServiceResolver *r,

995

1306

AvahiIfIndex interface,

996

1307

AvahiProtocol proto,

1004

1315

AVAHI_GCC_UNUSED AvahiStringList *txt,

1005

1316

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1006

1317

flags,

1007

void* mc){

1318

void *mc){

1008

1319

if(r == NULL){

1009

1320

return;

1010

1321

}

1013

1324

timed out */

1014

1325

1015

1326

if(quit_now){

1327

avahi_s_service_resolver_free(r);

1016

1328

return;

1017

1329

}

1018

1330

1063

1375

const char *domain,

1064

1376

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1065

1377

flags,

1066

void* mc){

1378

void *mc){

1067

1379

if(b == NULL){

1068

1380

return;

1069

1381

}

1129

1441

errno = old_errno;

1130

1442

}

1131

1443

1444

__attribute__((nonnull, warn_unused_result))

1132

1445

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

1133

1446

int ret;

1134

1447

error_t ret_errno;

1153

1466

return true;

1154

1467

}

1155

1468

1469

__attribute__((nonnull, warn_unused_result))

1156

1470

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

1157

1471

1158

1472

/* Reject the loopback device */

1200

1514

* corresponds to an acceptable network device.

1201

1515

* (This function is passed to scandir(3) as a filter function.)

1202

1516

*/

1517

__attribute__((nonnull, warn_unused_result))

1203

1518

int good_interface(const struct dirent *if_entry){

1204

1519

if(if_entry->d_name[0] == '.'){

1205

1520

return 0;

1223

1538

/*

1224

1539

* This function determines if a network interface is up.

1225

1540

*/

1541

__attribute__((nonnull, warn_unused_result))

1226

1542

bool interface_is_up(const char *interface){

1227

1543

struct ifreq ifr;

1228

1544

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

1239

1555

/*

1240

1556

* This function determines if a network interface is running

1241

1557

*/

1558

__attribute__((nonnull, warn_unused_result))

1242

1559

bool interface_is_running(const char *interface){

1243

1560

struct ifreq ifr;

1244

1561

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

1252

1569

return (bool)(ifr.ifr_flags & IFF_RUNNING);

1253

1570

}

1254

1571

1572

__attribute__((nonnull, pure, warn_unused_result))

1255

1573

int notdotentries(const struct dirent *direntry){

1256

1574

/* Skip "." and ".." */

1257

1575

if(direntry->d_name[0] == '.'

1264

1582

}

1265

1583

1266

1584

/* Is this directory entry a runnable program? */

1585

__attribute__((nonnull, warn_unused_result))

1267

1586

int runnable_hook(const struct dirent *direntry){

1268

1587

int ret;

1269

1588

size_t sret;

1277

1596

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

1278

1597

"abcdefghijklmnopqrstuvwxyz"

1279

1598

"0123456789"

1280

"_-");

1599

"_.-");

1281

1600

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

1282

1601

/* Contains non-allowed characters */

1283

1602

if(debug){

1287

1606

return 0;

1288

1607

}

1289

1608

1290

char *fullname = NULL;

1291

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

1292

if(ret < 0){

1293

perror_plus("asprintf");

1294

return 0;

1295

}

1296

1297

ret = stat(fullname, &st);

1609

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

1298

1610

if(ret == -1){

1299

1611

if(debug){

1300

1612

perror_plus("Could not stat hook");

1324

1636

return 1;

1325

1637

}

1326

1638

1639

__attribute__((nonnull, warn_unused_result))

1327

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1328

1641

mandos_context *mc){

1329

1642

int ret;

1333

1646

1334

1647

while(true){

1335

1648

if(mc->current_server == NULL){

1336

if (debug){

1649

if(debug){

1337

1650

fprintf_plus(stderr, "Wait until first server is found."

1338

1651

" No timeout!\n");

1339

1652

}

1340

1653

ret = avahi_simple_poll_iterate(s, -1);

1341

1654

} else {

1342

if (debug){

1655

if(debug){

1343

1656

fprintf_plus(stderr, "Check current_server if we should run"

1344

1657

" it, or wait\n");

1345

1658

}

1362

1675

- ((intmax_t)waited_time.tv_sec * 1000))

1363

1676

- ((intmax_t)waited_time.tv_nsec / 1000000));

1364

1677

1365

if (debug){

1678

if(debug){

1366

1679

fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",

1367

1680

block_time);

1368

1681

}

1390

1703

ret = avahi_simple_poll_iterate(s, (int)block_time);

1391

1704

}

1392

1705

if(ret != 0){

1393

if (ret > 0 or errno != EINTR){

1706

if(ret > 0 or errno != EINTR){

1394

1707

return (ret != 1) ? ret : 0;

1395

1708

}

1396

1709

}

1397

1710

}

1398

1711

}

1399

1712

1400

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

1401

error_t raise_privileges(void){

1402

error_t old_errno = errno;

1403

error_t ret_errno = 0;

1404

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

1405

ret_errno = errno;

1406

perror_plus("seteuid");

1407

}

1408

errno = old_errno;

1409

return ret_errno;

1410

}

1411

1412

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

1413

error_t raise_privileges_permanently(void){

1414

error_t old_errno = errno;

1415

error_t ret_errno = raise_privileges();

1416

if(ret_errno != 0){

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

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

1421

ret_errno = errno;

1422

perror_plus("seteuid");

1423

}

1424

errno = old_errno;

1425

return ret_errno;

1426

}

1427

1428

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

1429

error_t lower_privileges(void){

1430

error_t old_errno = errno;

1431

error_t ret_errno = 0;

1432

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

1433

ret_errno = errno;

1434

perror_plus("seteuid");

1435

}

1436

errno = old_errno;

1437

return ret_errno;

1438

}

1439

1440

/* Lower privileges permanently */

1441

error_t lower_privileges_permanently(void){

1442

error_t old_errno = errno;

1443

error_t ret_errno = 0;

1444

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

1445

ret_errno = errno;

1446

perror_plus("setuid");

1447

}

1448

errno = old_errno;

1449

return ret_errno;

1450

}

1451

1452

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

1713

__attribute__((nonnull))

1714

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

1453

1715

const float delay){

1454

struct dirent **direntries;

1716

struct dirent **direntries = NULL;

1717

if(hookdir_fd == -1){

1718

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1719

| O_CLOEXEC);

1720

if(hookdir_fd == -1){

1721

if(errno == ENOENT){

1722

if(debug){

1723

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

1724

" found\n", hookdir);

1725

}

1726

} else {

1727

perror_plus("open");

1728

}

1729

return;

1730

}

1731

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1734

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

1735

runnable_hook, alphasort);

1736

#else /* not __GLIBC_PREREQ(2, 15) */

1737

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

1738

alphasort);

1739

#endif /* not __GLIBC_PREREQ(2, 15) */

1740

#else /* not __GLIBC__ */

1741

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

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1744

if(numhooks == -1){

1745

perror_plus("scandir");

1746

return;

1747

}

1455

1748

struct dirent *direntry;

1456

1749

int ret;

1457

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

1458

alphasort);

1459

if(numhooks == -1){

1460

if(errno == ENOENT){

1461

if(debug){

1462

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

1463

" found\n", hookdir);

1464

}

1465

} else {

1466

perror_plus("scandir");

1750

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

1751

if(devnull == -1){

1752

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

1753

return;

1754

}

1755

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

1756

direntry = direntries[i];

1757

if(debug){

1758

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

1759

direntry->d_name);

1467

1760

}

1468

} else {

1469

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

1470

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

1471

direntry = direntries[i];

1472

char *fullname = NULL;

1473

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

1474

if(ret < 0){

1761

pid_t hook_pid = fork();

1762

if(hook_pid == 0){

1763

/* Child */

1764

/* Raise privileges */

1765

errno = raise_privileges_permanently();

1766

if(errno != 0){

1767

perror_plus("Failed to raise privileges");

1768

_exit(EX_NOPERM);

1769

}

1770

/* Set group */

1771

errno = 0;

1772

ret = setgid(0);

1773

if(ret == -1){

1774

perror_plus("setgid");

1775

_exit(EX_NOPERM);

1776

}

1777

/* Reset supplementary groups */

1778

errno = 0;

1779

ret = setgroups(0, NULL);

1780

if(ret == -1){

1781

perror_plus("setgroups");

1782

_exit(EX_NOPERM);

1783

}

1784

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

1785

if(ret == -1){

1786

perror_plus("setenv");

1787

_exit(EX_OSERR);

1788

}

1789

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

1790

if(ret == -1){

1791

perror_plus("setenv");

1792

_exit(EX_OSERR);

1793

}

1794

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

1795

if(ret == -1){

1796

perror_plus("setenv");

1797

_exit(EX_OSERR);

1798

}

1799

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

1800

if(ret == -1){

1801

perror_plus("setenv");

1802

_exit(EX_OSERR);

1803

}

1804

char *delaystring;

1805

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

1806

if(ret == -1){

1475

1807

perror_plus("asprintf");

1476

continue;

1477

}

1478

if(debug){

1479

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

1480

direntry->d_name);

1481

}

1482

pid_t hook_pid = fork();

1483

if(hook_pid == 0){

1484

/* Child */

1485

/* Raise privileges */

1486

raise_privileges_permanently();

1487

/* Set group */

1488

errno = 0;

1489

ret = setgid(0);

1490

if(ret == -1){

1491

perror_plus("setgid");

1492

}

1493

/* Reset supplementary groups */

1494

errno = 0;

1495

ret = setgroups(0, NULL);

1496

if(ret == -1){

1497

perror_plus("setgroups");

1498

}

1499

dup2(devnull, STDIN_FILENO);

1500

close(devnull);

1501

dup2(STDERR_FILENO, STDOUT_FILENO);

1502

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

1503

if(ret == -1){

1504

perror_plus("setenv");

1505

_exit(EX_OSERR);

1506

}

1507

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

1508

if(ret == -1){

1509

perror_plus("setenv");

1510

_exit(EX_OSERR);

1511

}

1512

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

1513

if(ret == -1){

1514

perror_plus("setenv");

1515

_exit(EX_OSERR);

1516

}

1517

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

1518

if(ret == -1){

1519

perror_plus("setenv");

1520

_exit(EX_OSERR);

1521

}

1522

char *delaystring;

1523

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

1524

if(ret == -1){

1525

perror_plus("asprintf");

1526

_exit(EX_OSERR);

1527

}

1528

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

1529

if(ret == -1){

1530

free(delaystring);

1531

perror_plus("setenv");

1532

_exit(EX_OSERR);

1533

}

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

1534

1812

free(delaystring);

1535

if(connect_to != NULL){

1536

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

1537

if(ret == -1){

1538

perror_plus("setenv");

1539

_exit(EX_OSERR);

1540

}

1541

}

1542

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

1543

perror_plus("execl");

1544

_exit(EXIT_FAILURE);

1545

}

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

free(delaystring);

1817

if(connect_to != NULL){

1818

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

1819

if(ret == -1){

1820

perror_plus("setenv");

1821

_exit(EX_OSERR);

1822

}

1823

}

1824

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

1825

direntry->d_name,

1826

O_RDONLY));

1827

if(hook_fd == -1){

1828

perror_plus("openat");

1829

_exit(EXIT_FAILURE);

1830

}

1831

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

1832

perror_plus("close");

1833

_exit(EXIT_FAILURE);

1834

}

1835

ret = dup2(devnull, STDIN_FILENO);

1836

if(ret == -1){

1837

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

1838

_exit(EX_OSERR);

1839

}

1840

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

1841

if(ret == -1){

1842

perror_plus("close");

1843

_exit(EX_OSERR);

1844

}

1845

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1846

if(ret == -1){

1847

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

1848

_exit(EX_OSERR);

1849

}

1850

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

1851

environ) == -1){

1852

perror_plus("fexecve");

1853

_exit(EXIT_FAILURE);

1854

}

1855

} else {

1856

if(hook_pid == -1){

1857

perror_plus("fork");

1858

free(direntry);

1859

continue;

1860

}

1861

int status;

1862

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

1863

perror_plus("waitpid");

1864

free(direntry);

1865

continue;

1866

}

1867

if(WIFEXITED(status)){

1868

if(WEXITSTATUS(status) != 0){

1869

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

1870

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

1871

WEXITSTATUS(status));

1872

free(direntry);

1873

continue;

1874

}

1875

} else if(WIFSIGNALED(status)){

1876

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

1877

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

1878

WTERMSIG(status));

1879

free(direntry);

1880

continue;

1546

1881

} else {

1547

int status;

1548

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

1549

perror_plus("waitpid");

1550

free(fullname);

1551

continue;

1552

}

1553

if(WIFEXITED(status)){

1554

if(WEXITSTATUS(status) != 0){

1555

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

1556

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

1557

WEXITSTATUS(status));

1558

free(fullname);

1559

continue;

1560

}

1561

} else if(WIFSIGNALED(status)){

1562

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

1563

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

1564

WTERMSIG(status));

1565

free(fullname);

1566

continue;

1567

} else {

1568

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

1569

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

1570

free(fullname);

1571

continue;

1572

}

1573

}

1574

free(fullname);

1575

if(debug){

1576

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

1577

direntry->d_name);

1578

}

1579

}

1580

close(devnull);

1581

}

1582

return true;

1882

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

1883

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

1884

free(direntry);

1885

continue;

1886

}

1887

}

1888

if(debug){

1889

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

1890

direntry->d_name);

1891

}

1892

free(direntry);

1893

}

1894

free(direntries);

1895

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

1896

perror_plus("close");

1897

} else {

1898

hookdir_fd = -1;

1899

}

1900

close(devnull);

1583

1901

}

1584

1902

1903

__attribute__((nonnull, warn_unused_result))

1585

1904

error_t bring_up_interface(const char *const interface,

1586

1905

const float delay){

1587

int sd = -1;

1588

1906

error_t old_errno = errno;

1589

error_t ret_errno = 0;

1590

int ret, ret_setflags;

1907

int ret;

1591

1908

struct ifreq network;

1592

1909

unsigned int if_index = if_nametoindex(interface);

1593

1910

if(if_index == 0){

1602

1919

}

1603

1920

1604

1921

if(not interface_is_up(interface)){

1605

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

1922

error_t ret_errno = 0, ioctl_errno = 0;

1923

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

1606

1924

ret_errno = errno;

1607

1925

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

1608

1926

"\"%s\"\n", interface);

1927

errno = old_errno;

1609

1928

return ret_errno;

1610

1929

}

1611

network.ifr_flags |= IFF_UP;

1930

network.ifr_flags |= IFF_UP; /* set flag */

1612

1931

1613

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1614

if(sd < 0){

1932

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

1933

if(sd == -1){

1615

1934

ret_errno = errno;

1616

1935

perror_plus("socket");

1617

1936

errno = old_errno;

1618

1937

return ret_errno;

1619

1938

}

1620

1939

1621

1940

if(quit_now){

1622

close(sd);

1941

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

1942

if(ret == -1){

1943

perror_plus("close");

1944

}

1623

1945

errno = old_errno;

1624

1946

return EINTR;

1625

1947

}

1629

1951

interface);

1630

1952

}

1631

1953

1632

/* Raise priviliges */

1633

raise_privileges();

1954

/* Raise privileges */

1955

ret_errno = raise_privileges();

1956

if(ret_errno != 0){

1957

errno = ret_errno;

1958

perror_plus("Failed to raise privileges");

1959

}

1634

1960

1635

1961

#ifdef __linux__

1636

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1637

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

1638

int ret_linux = klogctl(8, NULL, 5);

1639

bool restore_loglevel = true;

1640

if(ret_linux == -1){

1641

restore_loglevel = false;

1642

perror_plus("klogctl");

1962

int ret_linux;

1963

bool restore_loglevel = false;

1964

if(ret_errno == 0){

1965

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1966

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

1967

ret_linux = klogctl(8, NULL, 5);

1968

if(ret_linux == -1){

1969

perror_plus("klogctl");

1970

} else {

1971

restore_loglevel = true;

1972

}

1643

1973

}

1644

1974

#endif /* __linux__ */

1645

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

1646

ret_errno = errno;

1975

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

1976

ioctl_errno = errno;

1647

1977

#ifdef __linux__

1648

1978

if(restore_loglevel){

1649

1979

ret_linux = klogctl(7, NULL, 0);

1653

1983

}

1654

1984

#endif /* __linux__ */

1655

1985

1656

/* Lower privileges */

1657

lower_privileges();

1986

/* If raise_privileges() succeeded above */

1987

if(ret_errno == 0){

1988

/* Lower privileges */

1989

ret_errno = lower_privileges();

1990

if(ret_errno != 0){

1991

errno = ret_errno;

1992

perror_plus("Failed to lower privileges");

1993

}

1994

}

1658

1995

1659

1996

/* Close the socket */

1660

1997

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

1663

2000

}

1664

2001

1665

2002

if(ret_setflags == -1){

1666

errno = ret_errno;

2003

errno = ioctl_errno;

1667

2004

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1668

2005

errno = old_errno;

1669

return ret_errno;

2006

return ioctl_errno;

1670

2007

}

1671

2008

} else if(debug){

1672

2009

fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",

1690

2027

return 0;

1691

2028

}

1692

2029

2030

__attribute__((nonnull, warn_unused_result))

1693

2031

error_t take_down_interface(const char *const interface){

1694

int sd = -1;

1695

2032

error_t old_errno = errno;

1696

error_t ret_errno = 0;

1697

int ret, ret_setflags;

1698

2033

struct ifreq network;

1699

2034

unsigned int if_index = if_nametoindex(interface);

1700

2035

if(if_index == 0){

1703

2038

return ENXIO;

1704

2039

}

1705

2040

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

1706

2042

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

1707

2043

ret_errno = errno;

1708

2044

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

1709

2045

"\"%s\"\n", interface);

2046

errno = old_errno;

1710

2047

return ret_errno;

1711

2048

}

1712

2049

network.ifr_flags &= ~(short)IFF_UP; /* clear flag */

1713

2050

1714

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1715

if(sd < 0){

2051

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

2052

if(sd == -1){

1716

2053

ret_errno = errno;

1717

2054

perror_plus("socket");

1718

2055

errno = old_errno;

1724

2061

interface);

1725

2062

}

1726

2063

1727

/* Raise priviliges */

1728

raise_privileges();

1729

1730

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

1731

ret_errno = errno;

1732

1733

/* Lower privileges */

1734

lower_privileges();

2064

/* Raise privileges */

2065

ret_errno = raise_privileges();

2066

if(ret_errno != 0){

2067

errno = ret_errno;

2068

perror_plus("Failed to raise privileges");

2069

}

2070

2071

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

2072

ioctl_errno = errno;

2073

2074

/* If raise_privileges() succeeded above */

2075

if(ret_errno == 0){

2076

/* Lower privileges */

2077

ret_errno = lower_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to lower privileges");

2081

}

2082

}

1735

2083

1736

2084

/* Close the socket */

1737

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

2085

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

1738

2086

if(ret == -1){

1739

2087

perror_plus("close");

1740

2088

}

1741

2089

1742

2090

if(ret_setflags == -1){

1743

errno = ret_errno;

2091

errno = ioctl_errno;

1744

2092

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1745

2093

errno = old_errno;

1746

return ret_errno;

2094

return ioctl_errno;

1747

2095

}

1748

2096

} else if(debug){

1749

2097

fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",

1757

2105

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

1758

2106

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

1759

2107

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

1760

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

2108

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

1761

2109

.interfaces = NULL, .interfaces_size = 0 };

1762

2110

AvahiSServiceBrowser *sb = NULL;

1763

2111

error_t ret_errno;

1767

2115

int exitcode = EXIT_SUCCESS;

1768

2116

char *interfaces_to_take_down = NULL;

1769

2117

size_t interfaces_to_take_down_size = 0;

1770

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

1771

bool tempdir_created = false;

2118

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

2119

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

2120

char *tempdir = NULL;

1772

2121

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1773

2122

const char *seckey = PATHDIR "/" SECKEY;

1774

2123

const char *pubkey = PATHDIR "/" PUBKEY;

1775

2124

char *interfaces_hooks = NULL;

1776

size_t interfaces_hooks_size = 0;

1777

2125

1778

2126

bool gnutls_initialized = false;

1779

2127

bool gpgme_initialized = false;

1952

2300

goto end;

1953

2301

}

1954

2302

}

1955

2303

1956

2304

{

1957

2305

/* Work around Debian bug #633582:

1958

2306

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

1959

2307

1960

/* Re-raise priviliges */

1961

if(raise_privileges() == 0){

2308

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2312

perror_plus("Failed to raise privileges");

2313

} else {

1962

2314

struct stat st;

1963

2315

1964

2316

if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){

1981

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

1982

2334

}

1983

2335

}

1984

2336

1985

2337

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

1986

2338

int pubkey_fd = open(pubkey, O_RDONLY);

1987

2339

if(pubkey_fd == -1){

2002

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2003

2355

}

2004

2356

}

2005

2357

2006

2358

/* Lower privileges */

2007

errno = 0;

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2362

perror_plus("Failed to lower privileges");

2011

2363

}

2012

2364

}

2013

2365

}

2014

2366

2015

/* Remove empty interface names */

2367

/* Remove invalid interface names (except "none") */

2016

2368

{

2017

2369

char *interface = NULL;

2018

2370

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2019

2371

interface))){

2020

if(if_nametoindex(interface) == 0){

2021

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2372

if(strcmp(interface, "none") != 0

2373

and if_nametoindex(interface) == 0){

2374

if(interface[0] != '\0'){

2022

2375

fprintf_plus(stderr, "Not using nonexisting interface"

2023

2376

" \"%s\"\n", interface);

2024

2377

}

2030

2383

2031

2384

/* Run network hooks */

2032

2385

{

2033

2034

2386

if(mc.interfaces != NULL){

2035

2387

interfaces_hooks = malloc(mc.interfaces_size);

2036

2388

if(interfaces_hooks == NULL){

2038

2390

goto end;

2039

2391

}

2040

2392

memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);

2041

interfaces_hooks_size = mc.interfaces_size;

2042

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2043

(int)',');

2044

}

2045

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2046

interfaces_hooks : "", delay)){

2047

goto end;

2048

}

2393

argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');

2394

}

2395

run_network_hooks("start", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

2049

2397

}

2050

2398

2051

2399

if(not debug){

2129

2477

2130

2478

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

2131

2479

if(mc.interfaces == NULL){

2132

struct dirent **direntries;

2480

struct dirent **direntries = NULL;

2133

2481

/* Look for any good interfaces */

2134

2482

ret = scandir(sys_class_net, &direntries, good_interface,

2135

2483

alphasort);

2139

2487

ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,

2140

2488

direntries[i]->d_name);

2141

2489

if(ret_errno != 0){

2490

errno = ret_errno;

2142

2491

perror_plus("argz_add");

2492

free(direntries[i]);

2143

2493

continue;

2144

2494

}

2145

2495

if(debug){

2146

2496

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

2147

2497

direntries[i]->d_name);

2148

2498

}

2499

free(direntries[i]);

2149

2500

}

2150

2501

free(direntries);

2151

2502

} else {

2152

free(direntries);

2503

if(ret == 0){

2504

free(direntries);

2505

}

2153

2506

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

2154

2507

exitcode = EXIT_FAILURE;

2155

2508

goto end;

2156

2509

}

2157

2510

}

2158

2511

2512

/* Bring up interfaces which are down, and remove any "none"s */

2513

{

2514

char *interface = NULL;

2515

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2516

interface))){

2517

/* If interface name is "none", stop bringing up interfaces.

2518

Also remove all instances of "none" from the list */

2519

if(strcmp(interface, "none") == 0){

2520

argz_delete(&mc.interfaces, &mc.interfaces_size,

2521

interface);

2522

interface = NULL;

2523

while((interface = argz_next(mc.interfaces,

2524

mc.interfaces_size, interface))){

2525

if(strcmp(interface, "none") == 0){

2526

argz_delete(&mc.interfaces, &mc.interfaces_size,

2527

interface);

2528

interface = NULL;

2529

}

2530

}

2531

break;

2532

}

2533

bool interface_was_up = interface_is_up(interface);

2534

errno = bring_up_interface(interface, delay);

2535

if(not interface_was_up){

2536

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2538

} else {

2539

errno = argz_add(&interfaces_to_take_down,

2540

&interfaces_to_take_down_size,

2541

interface);

2542

if(errno != 0){

2543

perror_plus("argz_add");

2544

}

2545

}

2546

}

2547

}

2548

if(debug and (interfaces_to_take_down == NULL)){

2549

fprintf_plus(stderr, "No interfaces were brought up\n");

2550

}

2551

}

2552

2159

2553

/* If we only got one interface, explicitly use only that one */

2160

2554

if(argz_count(mc.interfaces, mc.interfaces_size) == 1){

2161

2555

if(debug){

2165

2559

if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);

2166

2560

}

2167

2561

2168

/* Bring up interfaces which are down */

2169

if(not (argz_count(mc.interfaces, mc.interfaces_size) == 1

2170

and strcmp(mc.interfaces, "none") == 0)){

2171

char *interface = NULL;

2172

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2173

interface))){

2174

bool interface_was_up = interface_is_up(interface);

2175

ret = bring_up_interface(interface, delay);

2176

if(not interface_was_up){

2177

if(ret != 0){

2178

errno = ret;

2179

perror_plus("Failed to bring up interface");

2180

} else {

2181

ret_errno = argz_add(&interfaces_to_take_down,

2182

&interfaces_to_take_down_size,

2183

interface);

2184

}

2185

}

2186

}

2187

free(mc.interfaces);

2188

mc.interfaces = NULL;

2189

mc.interfaces_size = 0;

2190

if(debug and (interfaces_to_take_down == NULL)){

2191

fprintf_plus(stderr, "No interfaces were brought up\n");

2192

}

2193

}

2194

2195

2562

if(quit_now){

2196

2563

goto end;

2197

2564

}

2209

2576

goto end;

2210

2577

}

2211

2578

2212

if(mkdtemp(tempdir) == NULL){

2579

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

2580

tempdir = mkdtemp(run_tempdir);

2581

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

2582

if(debug){

2583

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

2584

run_tempdir, old_tempdir);

2585

}

2586

tempdir = mkdtemp(old_tempdir);

2587

}

2588

if(tempdir == NULL){

2213

2589

perror_plus("mkdtemp");

2214

2590

goto end;

2215

2591

}

2216

tempdir_created = true;

2217

2592

2218

2593

if(quit_now){

2219

2594

goto end;

2255

2630

exitcode = EX_USAGE;

2256

2631

goto end;

2257

2632

}

2258

2633

2259

2634

if(quit_now){

2260

2635

goto end;

2261

2636

}

2291

2666

fprintf_plus(stderr, "Retrying in %d seconds\n",

2292

2667

(int)retry_interval);

2293

2668

}

2294

sleep((int)retry_interval);

2669

sleep((unsigned int)retry_interval);

2295

2670

}

2296

2671

2297

if (not quit_now){

2672

if(not quit_now){

2298

2673

exitcode = EXIT_SUCCESS;

2299

2674

}

2300

2675

2355

2730

if(debug){

2356

2731

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

2357

2732

}

2358

2733

2359

2734

ret = avahi_loop_with_timeout(simple_poll,

2360

2735

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

2361

2736

if(debug){

2370

2745

}

2371

2746

2372

2747

/* Cleanup things */

2748

free(mc.interfaces);

2749

2373

2750

if(sb != NULL)

2374

2751

avahi_s_service_browser_free(sb);

2375

2752

2395

2772

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

2396

2773

while(mc.current_server != NULL){

2397

2774

server *next = mc.current_server->next;

2775

#ifdef __GNUC__

2776

#pragma GCC diagnostic push

2777

#pragma GCC diagnostic ignored "-Wcast-qual"

2778

#endif

2779

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

2780

#ifdef __GNUC__

2781

#pragma GCC diagnostic pop

2782

#endif

2398

2783

free(mc.current_server);

2399

2784

mc.current_server = next;

2400

2785

}

2401

2786

}

2402

2787

2403

/* Re-raise priviliges */

2788

/* Re-raise privileges */

2404

2789

{

2405

raise_privileges();

2406

2407

/* Run network hooks */

2408

run_network_hooks("stop", interfaces_hooks != NULL ?

2409

interfaces_hooks : "", delay);

2410

2411

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

2412

{

2413

char *interface = NULL;

2414

while((interface=argz_next(interfaces_to_take_down,

2415

interfaces_to_take_down_size,

2416

interface))){

2417

ret_errno = take_down_interface(interface);

2418

if(ret_errno != 0){

2419

errno = ret_errno;

2420

perror_plus("Failed to take down interface");

2421

}

2422

}

2423

if(debug and (interfaces_to_take_down == NULL)){

2424

fprintf_plus(stderr, "No interfaces needed to be taken"

2425

" down\n");

2426

}

2427

}

2428

2429

lower_privileges_permanently();

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

2793

perror_plus("Failed to raise privileges");

2794

} else {

2795

2796

/* Run network hooks */

2797

run_network_hooks("stop", interfaces_hooks != NULL ?

2798

interfaces_hooks : "", delay);

2799

2800

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

2801

{

2802

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

2809

perror_plus("Failed to take down interface");

2810

}

2811

}

2812

if(debug and (interfaces_to_take_down == NULL)){

2813

fprintf_plus(stderr, "No interfaces needed to be taken"

2814

" down\n");

2815

}

2816

}

2817

}

2818

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

perror_plus("Failed to lower privileges permanently");

2823

}

2430

2824

}

2431

2825

2432

2826

free(interfaces_to_take_down);

2433

2827

free(interfaces_hooks);

2434

2828

2435

2829

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

2436

if(tempdir_created){

2830

if(tempdir != NULL){

2437

2831

struct dirent **direntries = NULL;

2438

struct dirent *direntry = NULL;

2439

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

2440

alphasort);

2441

if (numentries > 0){

2442

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

2443

direntry = direntries[i];

2444

char *fullname = NULL;

2445

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

2446

direntry->d_name);

2447

if(ret < 0){

2448

perror_plus("asprintf");

2449

continue;

2450

}

2451

ret = remove(fullname);

2452

if(ret == -1){

2453

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

2454

strerror(errno));

2455

}

2456

free(fullname);

2832

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

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

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

2842

notdotentries, alphasort);

2843

#else /* not __GLIBC_PREREQ(2, 15) */

2844

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

2845

alphasort);

2846

#endif /* not __GLIBC_PREREQ(2, 15) */

2847

#else /* not __GLIBC__ */

2848

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

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

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

2853

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

2854

if(ret == -1){

2855

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2856

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

2857

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

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

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

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

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

2869

perror_plus("rmdir");

2870

}

2457

2871

}

2458

}

2459

2460

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

2461

free(direntries);

2462

if (numentries == -1){

2463

perror_plus("scandir");

2464

}

2465

ret = rmdir(tempdir);

2466

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

2467

perror_plus("rmdir");

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

2468

2873

}

2469

2874

}

2470

2875