/mandos/trunk : revision 738.1.6

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);

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 delete_local_route() */

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_delete_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 debug_flag[] = "--debug";

715

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

716

if(pluginhelperdir == NULL){

717

if(debug){

718

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

719

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

720

}

721

return false;

722

}

723

724

char interface[IF_NAMESIZE];

725

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

726

perror_plus("if_indextoname");

727

return false;

728

}

729

730

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

731

if(devnull == -1){

732

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

733

return false;

734

}

735

pid_t pid = fork();

736

if(pid == 0){

737

/* Child */

738

/* Raise privileges */

739

errno = raise_privileges_permanently();

740

if(errno != 0){

741

perror_plus("Failed to raise privileges");

742

/* _exit(EX_NOPERM); */

743

} else {

744

/* Set group */

745

errno = 0;

746

ret = setgid(0);

747

if(ret == -1){

748

perror_plus("setgid");

749

_exit(EX_NOPERM);

750

}

751

/* Reset supplementary groups */

752

errno = 0;

753

ret = setgroups(0, NULL);

754

if(ret == -1){

755

perror_plus("setgroups");

756

_exit(EX_NOPERM);

757

}

758

}

759

ret = dup2(devnull, STDIN_FILENO);

760

if(ret == -1){

761

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

762

_exit(EX_OSERR);

763

}

764

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

765

if(ret == -1){

766

perror_plus("close");

767

_exit(EX_OSERR);

768

}

769

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

770

if(ret == -1){

771

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

772

_exit(EX_OSERR);

773

}

774

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

775

O_RDONLY

776

| O_DIRECTORY

777

| O_PATH

778

| O_CLOEXEC));

779

if(helperdir_fd == -1){

780

perror_plus("open");

781

_exit(EX_UNAVAILABLE);

782

}

783

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

784

helper, O_RDONLY));

785

if(helper_fd == -1){

786

perror_plus("openat");

787

_exit(EX_UNAVAILABLE);

788

}

789

TEMP_FAILURE_RETRY(close(helperdir_fd));

790

#ifdef __GNUC__

791

#pragma GCC diagnostic push

792

#pragma GCC diagnostic ignored "-Wcast-qual"

793

#endif

794

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

795

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

796

interface, debug ? debug_flag : NULL, NULL },

797

environ) == -1){

798

#ifdef __GNUC__

799

#pragma GCC diagnostic pop

800

#endif

801

perror_plus("fexecve");

802

_exit(EXIT_FAILURE);

803

}

804

}

805

if(pid == -1){

806

perror_plus("fork");

807

return false;

808

}

809

int status;

810

pid_t pret = -1;

811

errno = 0;

812

do {

813

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

814

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

815

int errno_raising = 0;

816

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

817

errno_raising = errno;

818

perror_plus("Failed to raise privileges in order to"

819

" kill helper program");

820

}

821

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

822

perror_plus("kill");

823

}

824

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

825

perror_plus("Failed to lower privileges after killing"

826

" helper program");

827

}

828

return false;

829

}

830

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

831

if(pret == -1){

832

perror_plus("waitpid");

833

return false;

834

}

835

if(WIFEXITED(status)){

836

if(WEXITSTATUS(status) != 0){

837

fprintf_plus(stderr, "Error: iprouteadddel exited"

838

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

839

return false;

840

}

841

return true;

842

}

843

if(WIFSIGNALED(status)){

844

fprintf_plus(stderr, "Error: iprouteadddel died by"

845

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

846

return false;

847

}

848

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

849

return false;

850

}

851

852

__attribute__((nonnull, warn_unused_result))

853

static bool add_local_route(const char *address,

854

AvahiIfIndex if_index){

855

if(debug){

856

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

857

}

858

return add_delete_local_route(true, address, if_index);

859

}

860

861

__attribute__((nonnull, warn_unused_result))

862

static bool delete_local_route(const char *address,

863

AvahiIfIndex if_index){

864

if(debug){

865

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

866

}

867

return add_delete_local_route(false, address, if_index);

868

}

869

623

870

/* Called when a Mandos server is found */

871

__attribute__((nonnull, warn_unused_result))

624

872

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

625

873

AvahiIfIndex if_index,

626

874

int af, mandos_context *mc){

627

875

int ret, tcp_sd = -1;

628

876

ssize_t sret;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

877

struct sockaddr_storage to;

633

878

char *buffer = NULL;

634

879

char *decrypted_buffer = NULL;

635

880

size_t buffer_length = 0;

638

883

int retval = -1;

639

884

gnutls_session_t session;

640

885

int pf; /* Protocol family */

886

bool route_added = false;

641

887

642

888

errno = 0;

643

889

701

947

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

702

948

}

703

949

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

950

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

705

951

if(tcp_sd < 0){

706

952

int e = errno;

707

953

perror_plus("socket");

716

962

717

963

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

718

964

if(af == AF_INET6){

719

to.in6.sin6_family = (sa_family_t)af;

720

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

965

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

966

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

721

967

} else { /* IPv4 */

722

to.in.sin_family = (sa_family_t)af;

723

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

968

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

969

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

724

970

}

725

971

if(ret < 0 ){

726

972

int e = errno;

735

981

goto mandos_end;

736

982

}

737

983

if(af == AF_INET6){

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

743

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

744

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

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

984

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

985

if(IN6_IS_ADDR_LINKLOCAL

986

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

748

987

if(if_index == AVAHI_IF_UNSPEC){

749

988

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

750

989

" incomplete without a network interface\n");

752

991

goto mandos_end;

753

992

}

754

993

/* Set the network interface number as scope */

755

to.in6.sin6_scope_id = (uint32_t)if_index;

994

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

756

995

}

757

996

} else {

758

to.in.sin_port = htons(port);

997

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

759

998

}

760

999

761

1000

if(quit_now){

778

1017

}

779

1018

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

780

1019

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

781

const char *pcret;

782

if(af == AF_INET6){

783

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

784

sizeof(addrstr));

785

} else {

786

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

787

sizeof(addrstr));

788

}

789

if(pcret == NULL){

790

perror_plus("inet_ntop");

791

} else {

792

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

793

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

794

}

795

}

796

}

797

798

if(quit_now){

799

errno = EINTR;

800

goto mandos_end;

801

}

802

803

if(af == AF_INET6){

804

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

805

} else {

806

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

807

}

808

if(ret < 0){

809

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

810

int e = errno;

811

perror_plus("connect");

812

errno = e;

813

}

814

goto mandos_end;

815

}

816

817

if(quit_now){

818

errno = EINTR;

819

goto mandos_end;

1020

if(af == AF_INET6){

1021

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

1022

sizeof(struct sockaddr_in6),

1023

addrstr, sizeof(addrstr), NULL, 0,

1024

NI_NUMERICHOST);

1025

} else {

1026

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

1027

sizeof(struct sockaddr_in),

1028

addrstr, sizeof(addrstr), NULL, 0,

1029

NI_NUMERICHOST);

1030

}

1031

if(ret == EAI_SYSTEM){

1032

perror_plus("getnameinfo");

1033

} else if(ret != 0) {

1034

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

1035

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

1036

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

1037

}

1038

}

1039

1040

if(quit_now){

1041

errno = EINTR;

1042

goto mandos_end;

1043

}

1044

1045

while(true){

1046

if(af == AF_INET6){

1047

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

1048

sizeof(struct sockaddr_in6));

1049

} else {

1050

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

1051

sizeof(struct sockaddr_in));

1052

}

1053

if(ret < 0){

1054

if(errno == ENETUNREACH

1055

and if_index != AVAHI_IF_UNSPEC

1056

and connect_to == NULL

1057

and not route_added and

1058

((af == AF_INET6 and not

1059

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1060

&to)->sin6_addr)))

1061

or (af == AF_INET and

1062

/* Not a a IPv4LL address */

1063

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

1064

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

1065

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

1066

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

1067

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

1068

connect to a Mandos server announced by Avahi on a server

1069

host with a global address. Work around this by retrying

1070

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

1071

1072

Avahi bug reference:

1073

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

1074

https://bugs.debian.org/587961

1075

*/

1076

if(debug){

1077

fprintf_plus(stderr, "Mandos server unreachable, trying"

1078

" direct route\n");

1079

}

1080

int e = errno;

1081

route_added = add_local_route(ip, if_index);

1082

if(route_added){

1083

continue;

1084

}

1085

errno = e;

1086

}

1087

if(errno != ECONNREFUSED or debug){

1088

int e = errno;

1089

perror_plus("connect");

1090

errno = e;

1091

}

1092

goto mandos_end;

1093

}

1094

1095

if(quit_now){

1096

errno = EINTR;

1097

goto mandos_end;

1098

}

1099

break;

820

1100

}

821

1101

822

1102

const char *out = mandos_protocol_version;

1005

1285

1006

1286

mandos_end:

1007

1287

{

1288

if(route_added){

1289

if(not delete_local_route(ip, if_index)){

1290

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

1291

" interface %d", ip, if_index);

1292

}

1293

}

1008

1294

int e = errno;

1009

1295

free(decrypted_buffer);

1010

1296

free(buffer);

1027

1313

return retval;

1028

1314

}

1029

1315

1316

__attribute__((nonnull))

1030

1317

static void resolve_callback(AvahiSServiceResolver *r,

1031

1318

AvahiIfIndex interface,

1032

1319

AvahiProtocol proto,

1040

1327

AVAHI_GCC_UNUSED AvahiStringList *txt,

1041

1328

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1042

1329

flags,

1043

void* mc){

1330

void *mc){

1044

1331

if(r == NULL){

1045

1332

return;

1046

1333

}

1049

1336

timed out */

1050

1337

1051

1338

if(quit_now){

1339

avahi_s_service_resolver_free(r);

1052

1340

return;

1053

1341

}

1054

1342

1099

1387

const char *domain,

1100

1388

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1101

1389

flags,

1102

void* mc){

1390

void *mc){

1103

1391

if(b == NULL){

1104

1392

return;

1105

1393

}

1165

1453

errno = old_errno;

1166

1454

}

1167

1455

1456

__attribute__((nonnull, warn_unused_result))

1168

1457

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

1169

1458

int ret;

1170

1459

error_t ret_errno;

1189

1478

return true;

1190

1479

}

1191

1480

1481

__attribute__((nonnull, warn_unused_result))

1192

1482

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

1193

1483

1194

1484

/* Reject the loopback device */

1236

1526

* corresponds to an acceptable network device.

1237

1527

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

1238

1528

*/

1529

__attribute__((nonnull, warn_unused_result))

1239

1530

int good_interface(const struct dirent *if_entry){

1240

1531

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

1241

1532

return 0;

1259

1550

/*

1260

1551

* This function determines if a network interface is up.

1261

1552

*/

1553

__attribute__((nonnull, warn_unused_result))

1262

1554

bool interface_is_up(const char *interface){

1263

1555

struct ifreq ifr;

1264

1556

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

1275

1567

/*

1276

1568

* This function determines if a network interface is running

1277

1569

*/

1570

__attribute__((nonnull, warn_unused_result))

1278

1571

bool interface_is_running(const char *interface){

1279

1572

struct ifreq ifr;

1280

1573

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

1288

1581

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

1289

1582

}

1290

1583

1584

__attribute__((nonnull, pure, warn_unused_result))

1291

1585

int notdotentries(const struct dirent *direntry){

1292

1586

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

1293

1587

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

1300

1594

}

1301

1595

1302

1596

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

1597

__attribute__((nonnull, warn_unused_result))

1303

1598

int runnable_hook(const struct dirent *direntry){

1304

1599

int ret;

1305

1600

size_t sret;

1313

1608

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

1314

1609

"abcdefghijklmnopqrstuvwxyz"

1315

1610

"0123456789"

1316

"_-");

1611

"_.-");

1317

1612

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

1318

1613

/* Contains non-allowed characters */

1319

1614

if(debug){

1323

1618

return 0;

1324

1619

}

1325

1620

1326

char *fullname = NULL;

1327

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

1328

if(ret < 0){

1329

perror_plus("asprintf");

1330

return 0;

1331

}

1332

1333

ret = stat(fullname, &st);

1621

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

1334

1622

if(ret == -1){

1335

1623

if(debug){

1336

1624

perror_plus("Could not stat hook");

1360

1648

return 1;

1361

1649

}

1362

1650

1651

__attribute__((nonnull, warn_unused_result))

1363

1652

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

1653

mandos_context *mc){

1365

1654

int ret;

1369

1658

1370

1659

while(true){

1371

1660

if(mc->current_server == NULL){

1372

if (debug){

1661

if(debug){

1373

1662

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

1374

1663

" No timeout!\n");

1375

1664

}

1376

1665

ret = avahi_simple_poll_iterate(s, -1);

1377

1666

} else {

1378

if (debug){

1667

if(debug){

1379

1668

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

1380

1669

" it, or wait\n");

1381

1670

}

1398

1687

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

1399

1688

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

1400

1689

1401

if (debug){

1690

if(debug){

1402

1691

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

1403

1692

block_time);

1404

1693

}

1426

1715

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

1427

1716

}

1428

1717

if(ret != 0){

1429

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

1718

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

1430

1719

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

1431

1720

}

1432

1721

}

1433

1722

}

1434

1723

}

1435

1724

1436

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

1437

error_t raise_privileges(void){

1438

error_t old_errno = errno;

1439

error_t ret_errno = 0;

1440

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

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1443

}

1444

errno = old_errno;

1445

return ret_errno;

1446

}

1447

1448

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

1449

error_t raise_privileges_permanently(void){

1450

error_t old_errno = errno;

1451

error_t ret_errno = raise_privileges();

1452

if(ret_errno != 0){

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

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

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1459

}

1460

errno = old_errno;

1461

return ret_errno;

1462

}

1463

1464

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

1465

error_t lower_privileges(void){

1466

error_t old_errno = errno;

1467

error_t ret_errno = 0;

1468

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

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1471

}

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

1476

/* Lower privileges permanently */

1477

error_t lower_privileges_permanently(void){

1478

error_t old_errno = errno;

1479

error_t ret_errno = 0;

1480

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

1481

ret_errno = errno;

1482

perror_plus("setuid");

1483

}

1484

errno = old_errno;

1485

return ret_errno;

1486

}

1487

1488

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

1725

__attribute__((nonnull))

1726

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

1489

1727

const float delay){

1490

struct dirent **direntries;

1728

struct dirent **direntries = NULL;

1729

if(hookdir_fd == -1){

1730

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1731

| O_CLOEXEC);

1732

if(hookdir_fd == -1){

1733

if(errno == ENOENT){

1734

if(debug){

1735

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

1736

" found\n", hookdir);

1737

}

1738

} else {

1739

perror_plus("open");

1740

}

1741

return;

1742

}

1743

}

1744

#ifdef __GLIBC__

1745

#if __GLIBC_PREREQ(2, 15)

1746

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

1747

runnable_hook, alphasort);

1748

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

1749

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

1750

alphasort);

1751

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

1752

#else /* not __GLIBC__ */

1753

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

1754

alphasort);

1755

#endif /* not __GLIBC__ */

1756

if(numhooks == -1){

1757

perror_plus("scandir");

1758

return;

1759

}

1491

1760

struct dirent *direntry;

1492

1761

int ret;

1493

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

1494

alphasort);

1495

if(numhooks == -1){

1496

if(errno == ENOENT){

1497

if(debug){

1498

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

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

1762

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

1763

if(devnull == -1){

1764

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

1765

return;

1766

}

1767

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

1768

direntry = direntries[i];

1769

if(debug){

1770

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

1771

direntry->d_name);

1503

1772

}

1504

} else {

1505

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

1506

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

1507

direntry = direntries[i];

1508

char *fullname = NULL;

1509

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

1510

if(ret < 0){

1773

pid_t hook_pid = fork();

1774

if(hook_pid == 0){

1775

/* Child */

1776

/* Raise privileges */

1777

errno = raise_privileges_permanently();

1778

if(errno != 0){

1779

perror_plus("Failed to raise privileges");

1780

_exit(EX_NOPERM);

1781

}

1782

/* Set group */

1783

errno = 0;

1784

ret = setgid(0);

1785

if(ret == -1){

1786

perror_plus("setgid");

1787

_exit(EX_NOPERM);

1788

}

1789

/* Reset supplementary groups */

1790

errno = 0;

1791

ret = setgroups(0, NULL);

1792

if(ret == -1){

1793

perror_plus("setgroups");

1794

_exit(EX_NOPERM);

1795

}

1796

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

1797

if(ret == -1){

1798

perror_plus("setenv");

1799

_exit(EX_OSERR);

1800

}

1801

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

1802

if(ret == -1){

1803

perror_plus("setenv");

1804

_exit(EX_OSERR);

1805

}

1806

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

1807

if(ret == -1){

1808

perror_plus("setenv");

1809

_exit(EX_OSERR);

1810

}

1811

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

1812

if(ret == -1){

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

char *delaystring;

1817

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

1818

if(ret == -1){

1511

1819

perror_plus("asprintf");

1512

continue;

1513

}

1514

if(debug){

1515

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

1516

direntry->d_name);

1517

}

1518

pid_t hook_pid = fork();

1519

if(hook_pid == 0){

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1535

dup2(devnull, STDIN_FILENO);

1536

close(devnull);

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1538

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

1539

if(ret == -1){

1540

perror_plus("setenv");

1541

_exit(EX_OSERR);

1542

}

1543

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

1544

if(ret == -1){

1545

perror_plus("setenv");

1546

_exit(EX_OSERR);

1547

}

1548

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

1549

if(ret == -1){

1550

perror_plus("setenv");

1551

_exit(EX_OSERR);

1552

}

1553

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

1554

if(ret == -1){

1555

perror_plus("setenv");

1556

_exit(EX_OSERR);

1557

}

1558

char *delaystring;

1559

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

1560

if(ret == -1){

1561

perror_plus("asprintf");

1562

_exit(EX_OSERR);

1563

}

1564

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

1565

if(ret == -1){

1566

free(delaystring);

1567

perror_plus("setenv");

1568

_exit(EX_OSERR);

1569

}

1820

_exit(EX_OSERR);

1821

}

1822

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

1823

if(ret == -1){

1570

1824

free(delaystring);

1571

if(connect_to != NULL){

1572

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

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

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

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

1825

perror_plus("setenv");

1826

_exit(EX_OSERR);

1827

}

1828

free(delaystring);

1829

if(connect_to != NULL){

1830

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

1831

if(ret == -1){

1832

perror_plus("setenv");

1833

_exit(EX_OSERR);

1834

}

1835

}

1836

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

1837

direntry->d_name,

1838

O_RDONLY));

1839

if(hook_fd == -1){

1840

perror_plus("openat");

1841

_exit(EXIT_FAILURE);

1842

}

1843

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

1844

perror_plus("close");

1845

_exit(EXIT_FAILURE);

1846

}

1847

ret = dup2(devnull, STDIN_FILENO);

1848

if(ret == -1){

1849

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

1850

_exit(EX_OSERR);

1851

}

1852

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

1853

if(ret == -1){

1854

perror_plus("close");

1855

_exit(EX_OSERR);

1856

}

1857

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1858

if(ret == -1){

1859

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

1860

_exit(EX_OSERR);

1861

}

1862

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

1863

environ) == -1){

1864

perror_plus("fexecve");

1865

_exit(EXIT_FAILURE);

1866

}

1867

} else {

1868

if(hook_pid == -1){

1869

perror_plus("fork");

1870

free(direntry);

1871

continue;

1872

}

1873

int status;

1874

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

1875

perror_plus("waitpid");

1876

free(direntry);

1877

continue;

1878

}

1879

if(WIFEXITED(status)){

1880

if(WEXITSTATUS(status) != 0){

1881

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

1882

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

1883

WEXITSTATUS(status));

1884

free(direntry);

1885

continue;

1886

}

1887

} else if(WIFSIGNALED(status)){

1888

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

1889

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

1890

WTERMSIG(status));

1891

free(direntry);

1892

continue;

1582

1893

} else {

1583

int status;

1584

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

1585

perror_plus("waitpid");

1586

free(fullname);

1587

continue;

1588

}

1589

if(WIFEXITED(status)){

1590

if(WEXITSTATUS(status) != 0){

1591

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

1592

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

1593

WEXITSTATUS(status));

1594

free(fullname);

1595

continue;

1596

}

1597

} else if(WIFSIGNALED(status)){

1598

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

1599

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

1600

WTERMSIG(status));

1601

free(fullname);

1602

continue;

1603

} else {

1604

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

1605

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

1606

free(fullname);

1607

continue;

1608

}

1609

}

1610

free(fullname);

1611

if(debug){

1612

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

1613

direntry->d_name);

1614

}

1615

}

1616

close(devnull);

1617

}

1618

return true;

1894

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

1895

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

1896

free(direntry);

1897

continue;

1898

}

1899

}

1900

if(debug){

1901

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

1902

direntry->d_name);

1903

}

1904

free(direntry);

1905

}

1906

free(direntries);

1907

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

1908

perror_plus("close");

1909

} else {

1910

hookdir_fd = -1;

1911

}

1912

close(devnull);

1619

1913

}

1620

1914

1915

__attribute__((nonnull, warn_unused_result))

1621

1916

error_t bring_up_interface(const char *const interface,

1622

1917

const float delay){

1623

int sd = -1;

1624

1918

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1919

int ret;

1627

1920

struct ifreq network;

1628

1921

unsigned int if_index = if_nametoindex(interface);

1629

1922

if(if_index == 0){

1638

1931

}

1639

1932

1640

1933

if(not interface_is_up(interface)){

1641

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

1934

error_t ret_errno = 0, ioctl_errno = 0;

1935

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

1642

1936

ret_errno = errno;

1643

1937

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

1644

1938

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

1939

errno = old_errno;

1645

1940

return ret_errno;

1646

1941

}

1647

network.ifr_flags |= IFF_UP;

1942

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

1648

1943

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1944

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

1945

if(sd == -1){

1651

1946

ret_errno = errno;

1652

1947

perror_plus("socket");

1653

1948

errno = old_errno;

1654

1949

return ret_errno;

1655

1950

}

1656

1951

1657

1952

if(quit_now){

1658

close(sd);

1953

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

1954

if(ret == -1){

1955

perror_plus("close");

1956

}

1659

1957

errno = old_errno;

1660

1958

return EINTR;

1661

1959

}

1665

1963

interface);

1666

1964

}

1667

1965

1668

/* Raise priviliges */

1669

raise_privileges();

1966

/* Raise privileges */

1967

ret_errno = raise_privileges();

1968

if(ret_errno != 0){

1969

errno = ret_errno;

1970

perror_plus("Failed to raise privileges");

1971

}

1670

1972

1671

1973

#ifdef __linux__

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

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

1674

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

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

1974

int ret_linux;

1975

bool restore_loglevel = false;

1976

if(ret_errno == 0){

1977

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1978

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

1979

ret_linux = klogctl(8, NULL, 5);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

} else {

1983

restore_loglevel = true;

1984

}

1679

1985

}

1680

1986

#endif /* __linux__ */

1681

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

1682

ret_errno = errno;

1987

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

1988

ioctl_errno = errno;

1683

1989

#ifdef __linux__

1684

1990

if(restore_loglevel){

1685

1991

ret_linux = klogctl(7, NULL, 0);

1689

1995

}

1690

1996

#endif /* __linux__ */

1691

1997

1692

/* Lower privileges */

1693

lower_privileges();

1998

/* If raise_privileges() succeeded above */

1999

if(ret_errno == 0){

2000

/* Lower privileges */

2001

ret_errno = lower_privileges();

2002

if(ret_errno != 0){

2003

errno = ret_errno;

2004

perror_plus("Failed to lower privileges");

2005

}

2006

}

1694

2007

1695

2008

/* Close the socket */

1696

2009

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

1699

2012

}

1700

2013

1701

2014

if(ret_setflags == -1){

1702

errno = ret_errno;

2015

errno = ioctl_errno;

1703

2016

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

2017

errno = old_errno;

1705

return ret_errno;

2018

return ioctl_errno;

1706

2019

}

1707

2020

} else if(debug){

1708

2021

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

1726

2039

return 0;

1727

2040

}

1728

2041

2042

__attribute__((nonnull, warn_unused_result))

1729

2043

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

2044

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1734

2045

struct ifreq network;

1735

2046

unsigned int if_index = if_nametoindex(interface);

1736

2047

if(if_index == 0){

1739

2050

return ENXIO;

1740

2051

}

1741

2052

if(interface_is_up(interface)){

2053

error_t ret_errno = 0, ioctl_errno = 0;

1742

2054

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

1743

2055

ret_errno = errno;

1744

2056

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

1745

2057

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

2058

errno = old_errno;

1746

2059

return ret_errno;

1747

2060

}

1748

2061

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

1749

2062

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

2063

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

2064

if(sd == -1){

1752

2065

ret_errno = errno;

1753

2066

perror_plus("socket");

1754

2067

errno = old_errno;

1760

2073

interface);

1761

2074

}

1762

2075

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

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

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

2076

/* Raise privileges */

2077

ret_errno = raise_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to raise privileges");

2081

}

2082

2083

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

2084

ioctl_errno = errno;

2085

2086

/* If raise_privileges() succeeded above */

2087

if(ret_errno == 0){

2088

/* Lower privileges */

2089

ret_errno = lower_privileges();

2090

if(ret_errno != 0){

2091

errno = ret_errno;

2092

perror_plus("Failed to lower privileges");

2093

}

2094

}

1771

2095

1772

2096

/* Close the socket */

1773

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

2097

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

1774

2098

if(ret == -1){

1775

2099

perror_plus("close");

1776

2100

}

1777

2101

1778

2102

if(ret_setflags == -1){

1779

errno = ret_errno;

2103

errno = ioctl_errno;

1780

2104

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

2105

errno = old_errno;

1782

return ret_errno;

2106

return ioctl_errno;

1783

2107

}

1784

2108

} else if(debug){

1785

2109

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

1793

2117

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

1794

2118

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

1795

2119

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

1796

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

2120

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

1797

2121

.interfaces = NULL, .interfaces_size = 0 };

1798

2122

AvahiSServiceBrowser *sb = NULL;

1799

2123

error_t ret_errno;

1803

2127

int exitcode = EXIT_SUCCESS;

1804

2128

char *interfaces_to_take_down = NULL;

1805

2129

size_t interfaces_to_take_down_size = 0;

1806

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

1807

bool tempdir_created = false;

2130

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

2131

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

2132

char *tempdir = NULL;

1808

2133

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1809

2134

const char *seckey = PATHDIR "/" SECKEY;

1810

2135

const char *pubkey = PATHDIR "/" PUBKEY;

1811

2136

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1813

2137

1814

2138

bool gnutls_initialized = false;

1815

2139

bool gpgme_initialized = false;

1988

2312

goto end;

1989

2313

}

1990

2314

}

1991

2315

1992

2316

{

1993

2317

/* Work around Debian bug #633582:

1994

2318

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

1995

2319

1996

/* Re-raise priviliges */

1997

if(raise_privileges() == 0){

2320

/* Re-raise privileges */

2321

ret_errno = raise_privileges();

2322

if(ret_errno != 0){

2323

errno = ret_errno;

2324

perror_plus("Failed to raise privileges");

2325

} else {

1998

2326

struct stat st;

1999

2327

2000

2328

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

2017

2345

TEMP_FAILURE_RETRY(close(seckey_fd));

2018

2346

}

2019

2347

}

2020

2348

2021

2349

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

2022

2350

int pubkey_fd = open(pubkey, O_RDONLY);

2023

2351

if(pubkey_fd == -1){

2038

2366

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

2367

}

2040

2368

}

2041

2369

2042

2370

/* Lower privileges */

2043

lower_privileges();

2371

ret_errno = lower_privileges();

2372

if(ret_errno != 0){

2373

errno = ret_errno;

2374

perror_plus("Failed to lower privileges");

2375

}

2044

2376

}

2045

2377

}

2046

2378

2070

2402

goto end;

2071

2403

}

2072

2404

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

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

2076

}

2077

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

2078

interfaces_hooks : "", delay)){

2079

goto end;

2080

}

2405

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

2406

}

2407

run_network_hooks("start", interfaces_hooks != NULL ?

2408

interfaces_hooks : "", delay);

2081

2409

}

2082

2410

2083

2411

if(not debug){

2161

2489

2162

2490

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

2163

2491

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2492

struct dirent **direntries = NULL;

2165

2493

/* Look for any good interfaces */

2166

2494

ret = scandir(sys_class_net, &direntries, good_interface,

2167

2495

alphasort);

2171

2499

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

2172

2500

direntries[i]->d_name);

2173

2501

if(ret_errno != 0){

2502

errno = ret_errno;

2174

2503

perror_plus("argz_add");

2504

free(direntries[i]);

2175

2505

continue;

2176

2506

}

2177

2507

if(debug){

2178

2508

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

2179

2509

direntries[i]->d_name);

2180

2510

}

2511

free(direntries[i]);

2181

2512

}

2182

2513

free(direntries);

2183

2514

} else {

2184

free(direntries);

2515

if(ret == 0){

2516

free(direntries);

2517

}

2185

2518

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

2186

2519

exitcode = EXIT_FAILURE;

2187

2520

goto end;

2210

2543

break;

2211

2544

}

2212

2545

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2546

errno = bring_up_interface(interface, delay);

2214

2547

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2548

if(errno != 0){

2217

2549

perror_plus("Failed to bring up interface");

2218

2550

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2551

errno = argz_add(&interfaces_to_take_down,

2552

&interfaces_to_take_down_size,

2553

interface);

2554

if(errno != 0){

2555

perror_plus("argz_add");

2556

}

2222

2557

}

2223

2558

}

2224

2559

}

2253

2588

goto end;

2254

2589

}

2255

2590

2256

if(mkdtemp(tempdir) == NULL){

2591

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

2592

tempdir = mkdtemp(run_tempdir);

2593

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

2594

if(debug){

2595

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

2596

run_tempdir, old_tempdir);

2597

}

2598

tempdir = mkdtemp(old_tempdir);

2599

}

2600

if(tempdir == NULL){

2257

2601

perror_plus("mkdtemp");

2258

2602

goto end;

2259

2603

}

2260

tempdir_created = true;

2261

2604

2262

2605

if(quit_now){

2263

2606

goto end;

2338

2681

sleep((unsigned int)retry_interval);

2339

2682

}

2340

2683

2341

if (not quit_now){

2684

if(not quit_now){

2342

2685

exitcode = EXIT_SUCCESS;

2343

2686

}

2344

2687

2399

2742

if(debug){

2400

2743

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

2401

2744

}

2402

2745

2403

2746

ret = avahi_loop_with_timeout(simple_poll,

2404

2747

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

2405

2748

if(debug){

2441

2784

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

2442

2785

while(mc.current_server != NULL){

2443

2786

server *next = mc.current_server->next;

2787

#ifdef __GNUC__

2788

#pragma GCC diagnostic push

2789

#pragma GCC diagnostic ignored "-Wcast-qual"

2790

#endif

2791

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

2792

#ifdef __GNUC__

2793

#pragma GCC diagnostic pop

2794

#endif

2444

2795

free(mc.current_server);

2445

2796

mc.current_server = next;

2446

2797

}

2447

2798

}

2448

2799

2449

/* Re-raise priviliges */

2800

/* Re-raise privileges */

2450

2801

{

2451

raise_privileges();

2452

2453

/* Run network hooks */

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2456

2457

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

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

2467

}

2468

}

2469

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

2470

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

2471

" down\n");

2472

}

2473

}

2474

2475

lower_privileges_permanently();

2802

ret_errno = raise_privileges();

2803

if(ret_errno != 0){

2804

errno = ret_errno;

2805

perror_plus("Failed to raise privileges");

2806

} else {

2807

2808

/* Run network hooks */

2809

run_network_hooks("stop", interfaces_hooks != NULL ?

2810

interfaces_hooks : "", delay);

2811

2812

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

2813

{

2814

char *interface = NULL;

2815

while((interface=argz_next(interfaces_to_take_down,

2816

interfaces_to_take_down_size,

2817

interface))){

2818

ret_errno = take_down_interface(interface);

2819

if(ret_errno != 0){

2820

errno = ret_errno;

2821

perror_plus("Failed to take down interface");

2822

}

2823

}

2824

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

2825

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

2826

" down\n");

2827

}

2828

}

2829

}

2830

2831

ret_errno = lower_privileges_permanently();

2832

if(ret_errno != 0){

2833

errno = ret_errno;

2834

perror_plus("Failed to lower privileges permanently");

2835

}

2476

2836

}

2477

2837

2478

2838

free(interfaces_to_take_down);

2479

2839

free(interfaces_hooks);

2480

2840

2481

2841

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

2482

if(tempdir_created){

2842

if(tempdir != NULL){

2483

2843

struct dirent **direntries = NULL;

2484

struct dirent *direntry = NULL;

2485

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

2486

alphasort);

2487

if (numentries > 0){

2488

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

2489

direntry = direntries[i];

2490

char *fullname = NULL;

2491

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

2492

direntry->d_name);

2493

if(ret < 0){

2494

perror_plus("asprintf");

2495

continue;

2496

}

2497

ret = remove(fullname);

2498

if(ret == -1){

2499

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

2500

strerror(errno));

2501

}

2502

free(fullname);

2844

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

2845

| O_NOFOLLOW

2846

| O_DIRECTORY

2847

| O_PATH));

2848

if(tempdir_fd == -1){

2849

perror_plus("open");

2850

} else {

2851

#ifdef __GLIBC__

2852

#if __GLIBC_PREREQ(2, 15)

2853

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

2854

notdotentries, alphasort);

2855

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

2856

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

2857

alphasort);

2858

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

2859

#else /* not __GLIBC__ */

2860

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

2861

alphasort);

2862

#endif /* not __GLIBC__ */

2863

if(numentries >= 0){

2864

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

2865

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

2866

if(ret == -1){

2867

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

2868

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

2869

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

2870

}

2871

free(direntries[i]);

2872

}

2873

2874

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

2875

free(direntries);

2876

if(numentries == -1){

2877

perror_plus("scandir");

2878

}

2879

ret = rmdir(tempdir);

2880

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

2881

perror_plus("rmdir");

2882

}

2503

2883

}

2504

}

2505

2506

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

2507

free(direntries);

2508

if (numentries == -1){

2509

perror_plus("scandir");

2510

}

2511

ret = rmdir(tempdir);

2512

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

2513

perror_plus("rmdir");

2884

TEMP_FAILURE_RETRY(close(tempdir_fd));

2514

2885

}

2515

2886

}

2516

2887