/mandos/release : revision 237.14.1

9

* "browse_callback", and parts of "main".

10

*

11

* Everything else is

12

13

14

*

15

* This file is part of Mandos.

16

*

17

* Mandos is free software: you can redistribute it and/or modify it

18

* under the terms of the GNU General Public License as published by

19

* the Free Software Foundation, either version 3 of the License, or

20

* (at your option) any later version.

21

*

22

* Mandos is distributed in the hope that it will be useful, but

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

17

* published by the Free Software Foundation, either version 3 of the

18

* License, or (at your option) any later version.

19

*

20

* This program is distributed in the hope that it will be useful, but

23

21

* WITHOUT ANY WARRANTY; without even the implied warranty of

24

22

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

25

23

* General Public License for more details.

26

24

*

27

25

* You should have received a copy of the GNU General Public License

28

* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

26

* along with this program. If not, see

27

* <http://www.gnu.org/licenses/>.

29

28

*

30

29

* Contact the authors at <mandos@recompile.se>.

31

30

*/

33

32

/* Needed by GPGME, specifically gpgme_data_seek() */

34

33

#ifndef _LARGEFILE_SOURCE

35

34

#define _LARGEFILE_SOURCE

36

#endif /* not _LARGEFILE_SOURCE */

35

#endif

37

36

#ifndef _FILE_OFFSET_BITS

38

37

#define _FILE_OFFSET_BITS 64

39

#endif /* not _FILE_OFFSET_BITS */

40

41

#define _GNU_SOURCE /* program_invocation_short_name,

42

TEMP_FAILURE_RETRY(), O_CLOEXEC,

43

scandirat(), asprintf() */

38

#endif

39

40

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */

41

42

#include <stdio.h> /* fprintf(), stderr, fwrite(),

43

stdout, ferror(), remove() */

44

#include <stdint.h> /* uint16_t, uint32_t */

45

#include <stddef.h> /* NULL, size_t, ssize_t */

46

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

47

strtof(), abort() */

44

48

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

45

#include <argp.h> /* argp_program_version,

46

argp_program_bug_address,

47

struct argp_option,

48

struct argp_state, argp_error(),

49

argp_state_help,

50

ARGP_HELP_STD_HELP,

51

ARGP_HELP_EXIT_ERR,

52

ARGP_HELP_EXIT_OK, ARGP_HELP_USAGE,

53

argp_err_exit_status,

54

ARGP_ERR_UNKNOWN, struct argp,

55

argp_parse(), ARGP_IN_ORDER,

56

ARGP_NO_HELP */

57

#include <stddef.h> /* NULL, size_t */

58

#include <sys/types.h> /* uid_t, gid_t, sig_atomic_t,

59

seteuid(), setuid(), pid_t,

60

setgid(), getuid(), getgid() */

61

#include <unistd.h> /* uid_t, gid_t, TEMP_FAILURE_RETRY(),

62

seteuid(), setuid(), close(),

63

ssize_t, read(), fork(), setgid(),

64

_exit(), dup2(), STDIN_FILENO,

65

STDERR_FILENO, STDOUT_FILENO,

66

fexecve(), write(), getuid(),

67

getgid(), fchown(), symlink(),

68

sleep(), unlinkat(), pause() */

69

#include <netinet/in.h> /* in_port_t, struct sockaddr_in6,

70

sa_family_t, struct sockaddr_in,

71

htons(), IN6_IS_ADDR_LINKLOCAL,

72

INET_ADDRSTRLEN, INET6_ADDRSTRLEN,

73

ntohl(), IPPROTO_IP */

74

#include <time.h> /* struct timespec, clock_gettime(),

75

CLOCK_MONOTONIC, time_t, struct tm,

76

gmtime_r(), clock_settime(),

77

CLOCK_REALTIME, nanosleep() */

78

#include <errno.h> /* errno,

79

program_invocation_short_name,

80

EINTR, EINVAL, ENETUNREACH,

81

EHOSTUNREACH, ECONNREFUSED, EPROTO,

82

EIO, ENOENT, ENXIO, error_t,

83

ENOMEM, EISDIR, ENOTEMPTY */

84

#include <stdio.h> /* fprintf(), stderr, perror(), FILE,

85

vfprintf(), off_t, SEEK_SET,

86

stdout, fwrite(), ferror(),

87

fflush(), asprintf() */

88

#include <stdarg.h> /* va_list, va_start(), vfprintf() */

89

#include <stdlib.h> /* realloc(), free(), malloc(),

90

getenv(), EXIT_FAILURE, setenv(),

91

EXIT_SUCCESS, strtof(), strtod(),

92

srand(), mkdtemp(), abort() */

93

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

94

strerror(), strncpy(), strspn(),

95

memcpy(), strrchr(), strchr(),

96

strsignal() */

97

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

98

O_PATH, O_CLOEXEC, openat(),

99

O_NOFOLLOW, AT_REMOVEDIR */

100

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

101

#include <sys/stat.h> /* struct stat, fstat(), fstatat(),

102

S_ISREG(), S_IXUSR, S_IXGRP,

103

S_IXOTH, lstat() */

104

#include <net/if.h> /* IF_NAMESIZE, if_indextoname(),

105

if_nametoindex(), SIOCGIFFLAGS,

106

IFF_LOOPBACK, IFF_POINTOPOINT,

107

IFF_BROADCAST, IFF_NOARP, IFF_UP,

108

IFF_RUNNING, SIOCSIFFLAGS */

109

#include <sysexits.h> /* EX_NOPERM, EX_OSERR,

110

EX_UNAVAILABLE, EX_USAGE */

111

#include <grp.h> /* setgroups() */

112

#include <sys/wait.h> /* waitpid(), WIFEXITED(),

113

WEXITSTATUS(), WIFSIGNALED(),

114

WTERMSIG() */

115

#include <signal.h> /* kill(), SIGTERM, struct sigaction,

116

SIG_DFL, sigemptyset(),

117

sigaddset(), SIGINT, SIGHUP,

118

SIG_IGN, raise() */

119

#include <sys/socket.h> /* struct sockaddr_storage, AF_INET6,

120

PF_INET6, AF_INET, PF_INET,

121

socket(), SOCK_STREAM,

122

SOCK_CLOEXEC, struct sockaddr,

123

connect(), SOCK_DGRAM */

124

#include <argz.h> /* argz_next(), argz_add_sep(),

125

argz_delete(), argz_stringify(),

126

argz_add(), argz_count() */

127

#include <inttypes.h> /* PRIuMAX, uintmax_t, uint32_t,

128

PRIdMAX, PRIu16, intmax_t,

49

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

50

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

51

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

52

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

53

sockaddr_in6, PF_INET6,

54

SOCK_STREAM, uid_t, gid_t, open(),

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect() */

59

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

60

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

61

*/

62

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

129

63

strtoimax() */

130

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

131

#include <stdint.h> /* uint32_t, intptr_t, uint16_t */

132

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

133

EAI_SYSTEM, gai_strerror() */

134

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

135

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

136

alphasort(), scandir() */

137

#include <limits.h> /* INT_MAX */

64

#include <assert.h> /* assert() */

65

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

66

program_invocation_short_name */

67

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

68

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

69

SIOCSIFFLAGS, if_indextoname(),

70

if_nametoindex(), IF_NAMESIZE */

71

#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,

72

INET_ADDRSTRLEN, INET6_ADDRSTRLEN

73

*/

74

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

75

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

76

setgid(), pause() */

77

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

78

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

79

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

80

argp_state, struct argp,

81

argp_parse(), ARGP_KEY_ARG,

82

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

83

#include <signal.h> /* sigemptyset(), sigaddset(),

84

sigaction(), SIGTERM, sig_atomic_t,

85

raise() */

86

#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

138

88

139

89

#ifdef __linux__

140

90

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

153

103

154

104

/* GnuTLS */

155

105

#include <gnutls/gnutls.h> /* All GnuTLS types, constants and

156

functions: gnutls_*, GNUTLS_* */

157

#if GNUTLS_VERSION_NUMBER < 0x030600

106

functions:

107

gnutls_*

108

init_gnutls_session(),

109

GNUTLS_* */

158

110

#include <gnutls/openpgp.h>

159

/* gnutls_certificate_set_openpgp_key_file(),

160

GNUTLS_OPENPGP_FMT_BASE64 */

161

#elif GNUTLS_VERSION_NUMBER >= 0x030606

162

#include <gnutls/x509.h> /* GNUTLS_PKCS_PLAIN,

163

GNUTLS_PKCS_NULL_PASSWORD */

164

#endif

111

/* gnutls_certificate_set_openpgp_key_file(),

112

GNUTLS_OPENPGP_FMT_BASE64 */

165

113

166

114

/* GPGME */

167

115

#include <gpgme.h> /* All GPGME types, constants and

168

116

functions:

169

gpgme_*, GPG_ERR_NO_*,

170

GPGME_IMPORT_*

171

GPGME_PROTOCOL_OpenPGP */

117

gpgme_*

118

GPGME_PROTOCOL_OpenPGP,

119

GPG_ERR_NO_* */

172

120

173

121

#define BUFFER_SIZE 256

174

122

175

123

#define PATHDIR "/conf/conf.d/mandos"

176

124

#define SECKEY "seckey.txt"

177

125

#define PUBKEY "pubkey.txt"

178

#define TLS_PRIVKEY "tls-privkey.pem"

179

#define TLS_PUBKEY "tls-pubkey.pem"

180

#define HOOKDIR "/lib/mandos/network-hooks.d"

181

126

182

127

bool debug = false;

183

128

static const char mandos_protocol_version[] = "1";

185

130

const char *argp_program_bug_address = "<mandos@recompile.se>";

186

131

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

187

132

char *connect_to = NULL;

188

const char *hookdir = HOOKDIR;

189

int hookdir_fd = -1;

190

uid_t uid = 65534;

191

gid_t gid = 65534;

192

133

193

134

/* Doubly linked list that need to be circularly linked when used */

194

135

typedef struct server{

195

136

const char *ip;

196

in_port_t port;

137

uint16_t port;

197

138

AvahiIfIndex if_index;

198

139

int af;

199

140

struct timespec last_seen;

203

144

204

145

/* Used for passing in values through the Avahi callback functions */

205

146

typedef struct {

147

AvahiSimplePoll *simple_poll;

206

148

AvahiServer *server;

207

149

gnutls_certificate_credentials_t cred;

208

150

unsigned int dh_bits;

210

152

const char *priority;

211

153

gpgme_ctx_t ctx;

212

154

server *current_server;

213

char *interfaces;

214

size_t interfaces_size;

215

155

} mandos_context;

216

156

217

/* global so signal handler can reach it*/

218

AvahiSimplePoll *simple_poll;

157

/* global context so signal handler can reach it*/

158

mandos_context mc = { .simple_poll = NULL, .server = NULL,

159

.dh_bits = 1024, .priority = "SECURE256"

160

":!CTYPE-X.509:+CTYPE-OPENPGP",

161

.current_server = NULL };

219

162

220

163

sig_atomic_t quit_now = 0;

221

164

int signal_received = 0;

222

165

223

166

/* Function to use when printing errors */

224

167

void perror_plus(const char *print_text){

225

int e = errno;

226

168

fprintf(stderr, "Mandos plugin %s: ",

227

169

program_invocation_short_name);

228

errno = e;

229

170

perror(print_text);

230

171

}

231

172

232

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

233

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

234

va_list ap;

235

va_start (ap, format);

236

237

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

238

program_invocation_short_name));

239

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

240

}

241

242

173

/*

243

174

* Make additional room in "buffer" for at least BUFFER_SIZE more

244

175

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

245

176

* "buffer_length" is how much is already used.

246

177

*/

247

__attribute__((nonnull, warn_unused_result))

248

178

size_t incbuffer(char **buffer, size_t buffer_length,

249

size_t buffer_capacity){

179

size_t buffer_capacity){

250

180

if(buffer_length + BUFFER_SIZE > buffer_capacity){

251

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

252

if(new_buf == NULL){

253

int old_errno = errno;

254

free(*buffer);

255

errno = old_errno;

256

*buffer = NULL;

181

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

182

if(buffer == NULL){

257

183

return 0;

258

184

}

259

*buffer = new_buf;

260

185

buffer_capacity += BUFFER_SIZE;

261

186

}

262

187

return buffer_capacity;

263

188

}

264

189

265

190

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

266

__attribute__((nonnull, warn_unused_result))

267

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

268

int af, server **current_server){

191

int add_server(const char *ip, uint16_t port,

192

AvahiIfIndex if_index,

193

int af){

269

194

int ret;

270

195

server *new_server = malloc(sizeof(server));

271

196

if(new_server == NULL){

272

197

perror_plus("malloc");

273

return false;

198

return -1;

274

199

}

275

200

*new_server = (server){ .ip = strdup(ip),

276

.port = port,

277

.if_index = if_index,

278

.af = af };

201

.port = port,

202

.if_index = if_index,

203

.af = af };

279

204

if(new_server->ip == NULL){

280

205

perror_plus("strdup");

281

free(new_server);

282

return false;

283

}

284

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

285

if(ret == -1){

286

perror_plus("clock_gettime");

287

#ifdef __GNUC__

288

#pragma GCC diagnostic push

289

#pragma GCC diagnostic ignored "-Wcast-qual"

290

#endif

291

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

292

#ifdef __GNUC__

293

#pragma GCC diagnostic pop

294

#endif

295

free(new_server);

296

return false;

206

return -1;

297

207

}

298

208

/* Special case of first server */

299

if(*current_server == NULL){

209

if (mc.current_server == NULL){

300

210

new_server->next = new_server;

301

211

new_server->prev = new_server;

302

*current_server = new_server;

212

mc.current_server = new_server;

213

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

303

214

} else {

304

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

305

new_server->next = *current_server;

306

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

215

new_server->next = mc.current_server;

216

new_server->prev = mc.current_server->prev;

307

217

new_server->prev->next = new_server;

308

(*current_server)->prev = new_server;

309

}

310

return true;

311

}

312

313

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

314

__attribute__((warn_unused_result))

315

int raise_privileges(void){

316

int old_errno = errno;

317

int ret = 0;

318

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

319

ret = errno;

320

}

321

errno = old_errno;

322

return ret;

323

}

324

325

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

326

__attribute__((warn_unused_result))

327

int raise_privileges_permanently(void){

328

int old_errno = errno;

329

int ret = raise_privileges();

330

if(ret != 0){

331

errno = old_errno;

332

return ret;

333

}

334

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

335

ret = errno;

336

}

337

errno = old_errno;

338

return ret;

339

}

340

341

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

342

__attribute__((warn_unused_result))

343

int lower_privileges(void){

344

int old_errno = errno;

345

int ret = 0;

346

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

347

ret = errno;

348

}

349

errno = old_errno;

350

return ret;

351

}

352

353

/* Lower privileges permanently */

354

__attribute__((warn_unused_result))

355

int lower_privileges_permanently(void){

356

int old_errno = errno;

357

int ret = 0;

358

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

359

ret = errno;

360

}

361

errno = old_errno;

362

return ret;

218

mc.current_server->prev = new_server;

219

}

220

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

221

if(ret == -1){

222

perror_plus("clock_gettime");

223

return -1;

224

}

225

return 0;

363

226

}

364

227

365

228

/*

366

229

* Initialize GPGME.

367

230

*/

368

__attribute__((nonnull, warn_unused_result))

369

static bool init_gpgme(const char * const seckey,

370

const char * const pubkey,

371

const char * const tempdir,

372

mandos_context *mc){

231

static bool init_gpgme(const char *seckey,

232

const char *pubkey, const char *tempdir){

373

233

gpgme_error_t rc;

374

234

gpgme_engine_info_t engine_info;

375

235

236

376

237

/*

377

238

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

378

239

*/

379

bool import_key(const char * const filename){

240

bool import_key(const char *filename){

380

241

int ret;

381

242

int fd;

382

243

gpgme_data_t pgp_data;

387

248

return false;

388

249

}

389

250

390

/* Workaround for systems without a real-time clock; see also

391

Debian bug #894495: <https://bugs.debian.org/894495> */

392

do {

393

{

394

time_t currtime = time(NULL);

395

if(currtime != (time_t)-1){

396

struct tm tm;

397

if(gmtime_r(&currtime, &tm) == NULL) {

398

perror_plus("gmtime_r");

399

break;

400

}

401

if(tm.tm_year != 70 or tm.tm_mon != 0){

402

break;

403

}

404

if(debug){

405

fprintf_plus(stderr, "System clock is January 1970");

406

}

407

} else {

408

if(debug){

409

fprintf_plus(stderr, "System clock is invalid");

410

}

411

}

412

}

413

struct stat keystat;

414

ret = fstat(fd, &keystat);

415

if(ret != 0){

416

perror_plus("fstat");

417

break;

418

}

419

ret = raise_privileges();

420

if(ret != 0){

421

errno = ret;

422

perror_plus("Failed to raise privileges");

423

break;

424

}

425

if(debug){

426

fprintf_plus(stderr,

427

"Setting system clock to key file mtime");

428

}

429

if(clock_settime(CLOCK_REALTIME, &keystat.st_mtim) != 0){

430

perror_plus("clock_settime");

431

}

432

ret = lower_privileges();

433

if(ret != 0){

434

errno = ret;

435

perror_plus("Failed to lower privileges");

436

}

437

} while(false);

438

439

251

rc = gpgme_data_new_from_fd(&pgp_data, fd);

440

252

if(rc != GPG_ERR_NO_ERROR){

441

fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",

442

gpgme_strsource(rc), gpgme_strerror(rc));

253

fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",

254

gpgme_strsource(rc), gpgme_strerror(rc));

443

255

return false;

444

256

}

445

257

446

rc = gpgme_op_import(mc->ctx, pgp_data);

258

rc = gpgme_op_import(mc.ctx, pgp_data);

447

259

if(rc != GPG_ERR_NO_ERROR){

448

fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",

449

gpgme_strsource(rc), gpgme_strerror(rc));

260

fprintf(stderr, "bad gpgme_op_import: %s: %s\n",

261

gpgme_strsource(rc), gpgme_strerror(rc));

450

262

return false;

451

263

}

452

{

453

gpgme_import_result_t import_result

454

= gpgme_op_import_result(mc->ctx);

455

if((import_result->imported < 1

456

or import_result->not_imported > 0)

457

and import_result->unchanged == 0){

458

fprintf_plus(stderr, "bad gpgme_op_import_results:\n");

459

fprintf_plus(stderr,

460

"The total number of considered keys: %d\n",

461

import_result->considered);

462

fprintf_plus(stderr,

463

"The number of keys without user ID: %d\n",

464

import_result->no_user_id);

465

fprintf_plus(stderr,

466

"The total number of imported keys: %d\n",

467

import_result->imported);

468

fprintf_plus(stderr, "The number of imported RSA keys: %d\n",

469

import_result->imported_rsa);

470

fprintf_plus(stderr, "The number of unchanged keys: %d\n",

471

import_result->unchanged);

472

fprintf_plus(stderr, "The number of new user IDs: %d\n",

473

import_result->new_user_ids);

474

fprintf_plus(stderr, "The number of new sub keys: %d\n",

475

import_result->new_sub_keys);

476

fprintf_plus(stderr, "The number of new signatures: %d\n",

477

import_result->new_signatures);

478

fprintf_plus(stderr, "The number of new revocations: %d\n",

479

import_result->new_revocations);

480

fprintf_plus(stderr,

481

"The total number of secret keys read: %d\n",

482

import_result->secret_read);

483

fprintf_plus(stderr,

484

"The number of imported secret keys: %d\n",

485

import_result->secret_imported);

486

fprintf_plus(stderr,

487

"The number of unchanged secret keys: %d\n",

488

import_result->secret_unchanged);

489

fprintf_plus(stderr, "The number of keys not imported: %d\n",

490

import_result->not_imported);

491

for(gpgme_import_status_t import_status

492

= import_result->imports;

493

import_status != NULL;

494

import_status = import_status->next){

495

fprintf_plus(stderr, "Import status for key: %s\n",

496

import_status->fpr);

497

if(import_status->result != GPG_ERR_NO_ERROR){

498

fprintf_plus(stderr, "Import result: %s: %s\n",

499

gpgme_strsource(import_status->result),

500

gpgme_strerror(import_status->result));

501

}

502

fprintf_plus(stderr, "Key status:\n");

503

fprintf_plus(stderr,

504

import_status->status & GPGME_IMPORT_NEW

505

? "The key was new.\n"

506

: "The key was not new.\n");

507

fprintf_plus(stderr,

508

import_status->status & GPGME_IMPORT_UID

509

? "The key contained new user IDs.\n"

510

: "The key did not contain new user IDs.\n");

511

fprintf_plus(stderr,

512

import_status->status & GPGME_IMPORT_SIG

513

? "The key contained new signatures.\n"

514

: "The key did not contain new signatures.\n");

515

fprintf_plus(stderr,

516

import_status->status & GPGME_IMPORT_SUBKEY

517

? "The key contained new sub keys.\n"

518

: "The key did not contain new sub keys.\n");

519

fprintf_plus(stderr,

520

import_status->status & GPGME_IMPORT_SECRET

521

? "The key contained a secret key.\n"

522

: "The key did not contain a secret key.\n");

523

}

524

return false;

525

}

526

}

527

264

528

ret = close(fd);

265

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

529

266

if(ret == -1){

530

267

perror_plus("close");

531

268

}

534

271

}

535

272

536

273

if(debug){

537

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

274

fprintf(stderr, "Initializing GPGME\n");

538

275

}

539

276

540

277

/* Init GPGME */

541

278

gpgme_check_version(NULL);

542

279

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

543

280

if(rc != GPG_ERR_NO_ERROR){

544

fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",

545

gpgme_strsource(rc), gpgme_strerror(rc));

281

fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",

282

gpgme_strsource(rc), gpgme_strerror(rc));

546

283

return false;

547

284

}

548

285

549

286

/* Set GPGME home directory for the OpenPGP engine only */

550

287

rc = gpgme_get_engine_info(&engine_info);

551

288

if(rc != GPG_ERR_NO_ERROR){

552

fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",

553

gpgme_strsource(rc), gpgme_strerror(rc));

289

fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",

290

gpgme_strsource(rc), gpgme_strerror(rc));

554

291

return false;

555

292

}

556

293

while(engine_info != NULL){

562

299

engine_info = engine_info->next;

563

300

}

564

301

if(engine_info == NULL){

565

fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",

566

tempdir);

302

fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);

567

303

return false;

568

304

}

569

305

570

306

/* Create new GPGME "context" */

571

rc = gpgme_new(&(mc->ctx));

307

rc = gpgme_new(&(mc.ctx));

572

308

if(rc != GPG_ERR_NO_ERROR){

573

fprintf_plus(stderr, "bad gpgme_new: %s: %s\n",

574

gpgme_strsource(rc), gpgme_strerror(rc));

309

fprintf(stderr, "bad gpgme_new: %s: %s\n",

310

gpgme_strsource(rc), gpgme_strerror(rc));

575

311

return false;

576

312

}

577

313

586

322

* Decrypt OpenPGP data.

587

323

* Returns -1 on error

588

324

*/

589

__attribute__((nonnull, warn_unused_result))

590

325

static ssize_t pgp_packet_decrypt(const char *cryptotext,

591

326

size_t crypto_size,

592

char **plaintext,

593

mandos_context *mc){

327

char **plaintext){

594

328

gpgme_data_t dh_crypto, dh_plain;

595

329

gpgme_error_t rc;

596

330

ssize_t ret;

598

332

ssize_t plaintext_length = 0;

599

333

600

334

if(debug){

601

fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");

335

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

602

336

}

603

337

604

338

/* Create new GPGME data buffer from memory cryptotext */

605

339

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

606

340

0);

607

341

if(rc != GPG_ERR_NO_ERROR){

608

fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",

609

gpgme_strsource(rc), gpgme_strerror(rc));

342

fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",

343

gpgme_strsource(rc), gpgme_strerror(rc));

610

344

return -1;

611

345

}

612

346

613

347

/* Create new empty GPGME data buffer for the plaintext */

614

348

rc = gpgme_data_new(&dh_plain);

615

349

if(rc != GPG_ERR_NO_ERROR){

616

fprintf_plus(stderr, "bad gpgme_data_new: %s: %s\n",

617

gpgme_strsource(rc), gpgme_strerror(rc));

350

fprintf(stderr, "bad gpgme_data_new: %s: %s\n",

351

gpgme_strsource(rc), gpgme_strerror(rc));

618

352

gpgme_data_release(dh_crypto);

619

353

return -1;

620

354

}

621

355

622

356

/* Decrypt data from the cryptotext data buffer to the plaintext

623

357

data buffer */

624

rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);

358

rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);

625

359

if(rc != GPG_ERR_NO_ERROR){

626

fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",

627

gpgme_strsource(rc), gpgme_strerror(rc));

360

fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",

361

gpgme_strsource(rc), gpgme_strerror(rc));

628

362

plaintext_length = -1;

629

363

if(debug){

630

364

gpgme_decrypt_result_t result;

631

result = gpgme_op_decrypt_result(mc->ctx);

365

result = gpgme_op_decrypt_result(mc.ctx);

632

366

if(result == NULL){

633

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

367

fprintf(stderr, "gpgme_op_decrypt_result failed\n");

634

368

} else {

635

if(result->unsupported_algorithm != NULL) {

636

fprintf_plus(stderr, "Unsupported algorithm: %s\n",

637

result->unsupported_algorithm);

638

}

639

fprintf_plus(stderr, "Wrong key usage: %s\n",

640

result->wrong_key_usage ? "Yes" : "No");

369

fprintf(stderr, "Unsupported algorithm: %s\n",

370

result->unsupported_algorithm);

371

fprintf(stderr, "Wrong key usage: %u\n",

372

result->wrong_key_usage);

641

373

if(result->file_name != NULL){

642

fprintf_plus(stderr, "File name: %s\n", result->file_name);

374

fprintf(stderr, "File name: %s\n", result->file_name);

643

375

}

644

645

for(gpgme_recipient_t r = result->recipients; r != NULL;

646

r = r->next){

647

fprintf_plus(stderr, "Public key algorithm: %s\n",

648

gpgme_pubkey_algo_name(r->pubkey_algo));

649

fprintf_plus(stderr, "Key ID: %s\n", r->keyid);

650

fprintf_plus(stderr, "Secret key available: %s\n",

651

r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");

376

gpgme_recipient_t recipient;

377

recipient = result->recipients;

378

while(recipient != NULL){

379

fprintf(stderr, "Public key algorithm: %s\n",

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

382

fprintf(stderr, "Secret key available: %s\n",

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

385

recipient = recipient->next;

652

386

}

653

387

}

654

388

}

656

390

}

657

391

658

392

if(debug){

659

fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");

393

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

660

394

}

661

395

662

396

/* Seek back to the beginning of the GPGME plaintext data buffer */

669

403

*plaintext = NULL;

670

404

while(true){

671

405

plaintext_capacity = incbuffer(plaintext,

672

(size_t)plaintext_length,

673

plaintext_capacity);

406

(size_t)plaintext_length,

407

plaintext_capacity);

674

408

if(plaintext_capacity == 0){

675

perror_plus("incbuffer");

676

plaintext_length = -1;

677

goto decrypt_end;

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

678

412

}

679

413

680

414

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

693

427

}

694

428

695

429

if(debug){

696

fprintf_plus(stderr, "Decrypted password is: ");

430

fprintf(stderr, "Decrypted password is: ");

697

431

for(ssize_t i = 0; i < plaintext_length; i++){

698

432

fprintf(stderr, "%02hhX ", (*plaintext)[i]);

699

433

}

710

444

return plaintext_length;

711

445

}

712

446

713

__attribute__((warn_unused_result, const))

714

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

715

if(str == NULL)

716

return "(unknown)";

717

return str;

718

}

719

720

__attribute__((warn_unused_result))

721

static const char *safer_gnutls_strerror(int value){

722

const char *ret = gnutls_strerror(value);

723

return safe_string(ret);

447

static const char * safer_gnutls_strerror(int value){

448

const char *ret = gnutls_strerror(value); /* Spurious warning from

449

-Wunreachable-code */

450

if(ret == NULL)

451

ret = "(unknown)";

452

return ret;

724

453

}

725

454

726

455

/* GnuTLS log function callback */

727

__attribute__((nonnull))

728

456

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

729

457

const char* string){

730

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

458

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

731

459

}

732

460

733

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

734

461

static int init_gnutls_global(const char *pubkeyfilename,

735

const char *seckeyfilename,

736

const char *dhparamsfilename,

737

mandos_context *mc){

462

const char *seckeyfilename){

738

463

int ret;

739

464

740

465

if(debug){

741

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

466

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

467

}

468

469

ret = gnutls_global_init();

470

if(ret != GNUTLS_E_SUCCESS){

471

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

472

safer_gnutls_strerror(ret));

473

return -1;

742

474

}

743

475

744

476

if(debug){

750

482

}

751

483

752

484

/* OpenPGP credentials */

753

ret = gnutls_certificate_allocate_credentials(&mc->cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

754

486

if(ret != GNUTLS_E_SUCCESS){

755

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

756

safer_gnutls_strerror(ret));

487

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

488

safer_gnutls_strerror(ret));

489

gnutls_global_deinit();

757

490

return -1;

758

491

}

759

492

760

493

if(debug){

761

fprintf_plus(stderr, "Attempting to use public key %s and"

762

" private key %s as GnuTLS credentials\n",

763

pubkeyfilename,

764

seckeyfilename);

494

fprintf(stderr, "Attempting to use OpenPGP public key %s and"

495

" secret key %s as GnuTLS credentials\n", pubkeyfilename,

496

seckeyfilename);

765

497

}

766

498

767

#if GNUTLS_VERSION_NUMBER >= 0x030606

768

ret = gnutls_certificate_set_rawpk_key_file

769

(mc->cred, pubkeyfilename, seckeyfilename,

770

GNUTLS_X509_FMT_PEM, /* format */

771

NULL, /* pass */

772

/* key_usage */

773

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

774

NULL, /* names */

775

0, /* names_length */

776

/* privkey_flags */

777

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

778

0); /* pkcs11_flags */

779

#elif GNUTLS_VERSION_NUMBER < 0x030600

780

499

ret = gnutls_certificate_set_openpgp_key_file

781

(mc->cred, pubkeyfilename, seckeyfilename,

500

(mc.cred, pubkeyfilename, seckeyfilename,

782

501

GNUTLS_OPENPGP_FMT_BASE64);

783

#else

784

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

785

#endif

786

502

if(ret != GNUTLS_E_SUCCESS){

787

fprintf_plus(stderr,

788

"Error[%d] while reading the key pair ('%s',"

789

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

790

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

791

safer_gnutls_strerror(ret));

503

fprintf(stderr,

504

"Error[%d] while reading the OpenPGP key pair ('%s',"

505

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

506

fprintf(stderr, "The GnuTLS error is: %s\n",

507

safer_gnutls_strerror(ret));

792

508

goto globalfail;

793

509

}

794

510

795

511

/* GnuTLS server initialization */

796

ret = gnutls_dh_params_init(&mc->dh_params);

797

if(ret != GNUTLS_E_SUCCESS){

798

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

799

" initialization: %s\n",

800

safer_gnutls_strerror(ret));

801

goto globalfail;

802

}

803

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

804

if(dhparamsfilename != NULL){

805

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

806

do {

807

int dhpfile = open(dhparamsfilename, O_RDONLY);

808

if(dhpfile == -1){

809

perror_plus("open");

810

dhparamsfilename = NULL;

811

break;

812

}

813

size_t params_capacity = 0;

814

while(true){

815

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

816

(size_t)params.size,

817

(size_t)params_capacity);

818

if(params_capacity == 0){

819

perror_plus("incbuffer");

820

free(params.data);

821

params.data = NULL;

822

dhparamsfilename = NULL;

823

break;

824

}

825

ssize_t bytes_read = read(dhpfile,

826

params.data + params.size,

827

BUFFER_SIZE);

828

/* EOF */

829

if(bytes_read == 0){

830

break;

831

}

832

/* check bytes_read for failure */

833

if(bytes_read < 0){

834

perror_plus("read");

835

free(params.data);

836

params.data = NULL;

837

dhparamsfilename = NULL;

838

break;

839

}

840

params.size += (unsigned int)bytes_read;

841

}

842

ret = close(dhpfile);

843

if(ret == -1){

844

perror_plus("close");

845

}

846

if(params.data == NULL){

847

dhparamsfilename = NULL;

848

}

849

if(dhparamsfilename == NULL){

850

break;

851

}

852

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

853

GNUTLS_X509_FMT_PEM);

854

if(ret != GNUTLS_E_SUCCESS){

855

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

856

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

857

safer_gnutls_strerror(ret));

858

dhparamsfilename = NULL;

859

}

860

free(params.data);

861

} while(false);

862

}

863

if(dhparamsfilename == NULL){

864

if(mc->dh_bits == 0){

865

#if GNUTLS_VERSION_NUMBER < 0x030600

866

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

867

/* Try to read the private key file */

868

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

869

do {

870

int secfile = open(seckeyfilename, O_RDONLY);

871

if(secfile == -1){

872

perror_plus("open");

873

break;

874

}

875

size_t buffer_capacity = 0;

876

while(true){

877

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

878

(size_t)buffer.size,

879

(size_t)buffer_capacity);

880

if(buffer_capacity == 0){

881

perror_plus("incbuffer");

882

free(buffer.data);

883

buffer.data = NULL;

884

break;

885

}

886

ssize_t bytes_read = read(secfile,

887

buffer.data + buffer.size,

888

BUFFER_SIZE);

889

/* EOF */

890

if(bytes_read == 0){

891

break;

892

}

893

/* check bytes_read for failure */

894

if(bytes_read < 0){

895

perror_plus("read");

896

free(buffer.data);

897

buffer.data = NULL;

898

break;

899

}

900

buffer.size += (unsigned int)bytes_read;

901

}

902

close(secfile);

903

} while(false);

904

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

905

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

906

if(buffer.data != NULL){

907

{

908

gnutls_openpgp_privkey_t privkey = NULL;

909

ret = gnutls_openpgp_privkey_init(&privkey);

910

if(ret != GNUTLS_E_SUCCESS){

911

fprintf_plus(stderr, "Error initializing OpenPGP key"

912

" structure: %s",

913

safer_gnutls_strerror(ret));

914

free(buffer.data);

915

buffer.data = NULL;

916

} else {

917

ret = gnutls_openpgp_privkey_import

918

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

919

if(ret != GNUTLS_E_SUCCESS){

920

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

921

safer_gnutls_strerror(ret));

922

privkey = NULL;

923

}

924

free(buffer.data);

925

buffer.data = NULL;

926

if(privkey != NULL){

927

/* Use private key to suggest an appropriate

928

sec_param */

929

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

930

gnutls_openpgp_privkey_deinit(privkey);

931

if(debug){

932

fprintf_plus(stderr, "This OpenPGP key implies using"

933

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

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)));

936

}

937

}

938

}

939

}

940

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

941

/* Err on the side of caution */

942

sec_param = GNUTLS_SEC_PARAM_ULTRA;

943

if(debug){

944

fprintf_plus(stderr, "Falling back to security parameter"

945

" \"%s\"\n",

946

safe_string(gnutls_sec_param_get_name

947

(sec_param)));

948

}

949

}

950

}

951

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

952

if(uret != 0){

953

mc->dh_bits = uret;

954

if(debug){

955

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

956

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

957

safe_string(gnutls_sec_param_get_name

958

(sec_param)),

959

mc->dh_bits);

960

}

961

} else {

962

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

963

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

964

safe_string(gnutls_sec_param_get_name

965

(sec_param)),

966

safer_gnutls_strerror(ret));

967

goto globalfail;

968

}

969

#endif

970

} else { /* dh_bits != 0 */

971

if(debug){

972

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

973

mc->dh_bits);

974

}

975

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

976

if(ret != GNUTLS_E_SUCCESS){

977

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

978

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

979

safer_gnutls_strerror(ret));

980

goto globalfail;

981

}

982

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

983

}

984

}

512

ret = gnutls_dh_params_init(&mc.dh_params);

513

if(ret != GNUTLS_E_SUCCESS){

514

fprintf(stderr, "Error in GnuTLS DH parameter initialization:"

515

" %s\n", safer_gnutls_strerror(ret));

516

goto globalfail;

517

}

518

ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);

519

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

522

goto globalfail;

523

}

524

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

985

526

986

527

return 0;

987

528

988

529

globalfail:

989

530

990

gnutls_certificate_free_credentials(mc->cred);

991

gnutls_dh_params_deinit(mc->dh_params);

531

gnutls_certificate_free_credentials(mc.cred);

532

gnutls_global_deinit();

533

gnutls_dh_params_deinit(mc.dh_params);

992

534

return -1;

993

535

}

994

536

995

__attribute__((nonnull, warn_unused_result))

996

static int init_gnutls_session(gnutls_session_t *session,

997

mandos_context *mc){

537

static int init_gnutls_session(gnutls_session_t *session){

998

538

int ret;

999

539

/* GnuTLS session creation */

1000

540

do {

1001

ret = gnutls_init(session, (GNUTLS_SERVER

1002

#if GNUTLS_VERSION_NUMBER >= 0x030506

1003

| GNUTLS_NO_TICKETS

1004

#endif

1005

#if GNUTLS_VERSION_NUMBER >= 0x030606

1006

| GNUTLS_ENABLE_RAWPK

1007

#endif

1008

));

541

ret = gnutls_init(session, GNUTLS_SERVER);

1009

542

if(quit_now){

1010

543

return -1;

1011

544

}

1012

545

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

1013

546

if(ret != GNUTLS_E_SUCCESS){

1014

fprintf_plus(stderr,

1015

"Error in GnuTLS session initialization: %s\n",

1016

safer_gnutls_strerror(ret));

547

fprintf(stderr, "Error in GnuTLS session initialization: %s\n",

548

safer_gnutls_strerror(ret));

1017

549

}

1018

550

1019

551

{

1020

552

const char *err;

1021

553

do {

1022

ret = gnutls_priority_set_direct(*session, mc->priority, &err);

554

ret = gnutls_priority_set_direct(*session, mc.priority, &err);

1023

555

if(quit_now){

1024

556

gnutls_deinit(*session);

1025

557

return -1;

1026

558

}

1027

559

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

1028

560

if(ret != GNUTLS_E_SUCCESS){

1029

fprintf_plus(stderr, "Syntax error at: %s\n", err);

1030

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

1031

safer_gnutls_strerror(ret));

561

fprintf(stderr, "Syntax error at: %s\n", err);

562

fprintf(stderr, "GnuTLS error: %s\n",

563

safer_gnutls_strerror(ret));

1032

564

gnutls_deinit(*session);

1033

565

return -1;

1034

566

}

1036

568

1037

569

do {

1038

570

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1039

mc->cred);

571

mc.cred);

1040

572

if(quit_now){

1041

573

gnutls_deinit(*session);

1042

574

return -1;

1043

575

}

1044

576

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

1045

577

if(ret != GNUTLS_E_SUCCESS){

1046

fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",

1047

safer_gnutls_strerror(ret));

578

fprintf(stderr, "Error setting GnuTLS credentials: %s\n",

579

safer_gnutls_strerror(ret));

1048

580

gnutls_deinit(*session);

1049

581

return -1;

1050

582

}

1052

584

/* ignore client certificate if any. */

1053

585

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1054

586

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

588

1055

589

return 0;

1056

590

}

1057

591

1059

593

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

1060

594

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

1061

595

1062

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

1063

__attribute__((nonnull, warn_unused_result))

1064

static bool add_delete_local_route(const bool add,

1065

const char *address,

1066

AvahiIfIndex if_index){

1067

int ret;

1068

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

1069

char add_arg[] = "add";

1070

char delete_arg[] = "delete";

1071

char debug_flag[] = "--debug";

1072

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1073

if(pluginhelperdir == NULL){

1074

if(debug){

1075

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1076

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

1077

}

1078

return false;

1079

}

1080

1081

char interface[IF_NAMESIZE];

1082

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

1083

perror_plus("if_indextoname");

1084

return false;

1085

}

1086

1087

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

1088

if(devnull == -1){

1089

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

1090

return false;

1091

}

1092

pid_t pid = fork();

1093

if(pid == 0){

1094

/* Child */

1095

/* Raise privileges */

1096

errno = raise_privileges_permanently();

1097

if(errno != 0){

1098

perror_plus("Failed to raise privileges");

1099

/* _exit(EX_NOPERM); */

1100

} else {

1101

/* Set group */

1102

errno = 0;

1103

ret = setgid(0);

1104

if(ret == -1){

1105

perror_plus("setgid");

1106

close(devnull);

1107

_exit(EX_NOPERM);

1108

}

1109

/* Reset supplementary groups */

1110

errno = 0;

1111

ret = setgroups(0, NULL);

1112

if(ret == -1){

1113

perror_plus("setgroups");

1114

close(devnull);

1115

_exit(EX_NOPERM);

1116

}

1117

}

1118

ret = dup2(devnull, STDIN_FILENO);

1119

if(ret == -1){

1120

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

1121

close(devnull);

1122

_exit(EX_OSERR);

1123

}

1124

ret = close(devnull);

1125

if(ret == -1){

1126

perror_plus("close");

1127

}

1128

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1129

if(ret == -1){

1130

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

1131

_exit(EX_OSERR);

1132

}

1133

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

1134

O_RDONLY

1135

| O_DIRECTORY

1136

| O_PATH

1137

| O_CLOEXEC));

1138

if(helperdir_fd == -1){

1139

perror_plus("open");

1140

_exit(EX_UNAVAILABLE);

1141

}

1142

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

1143

helper, O_RDONLY));

1144

if(helper_fd == -1){

1145

perror_plus("openat");

1146

close(helperdir_fd);

1147

_exit(EX_UNAVAILABLE);

1148

}

1149

close(helperdir_fd);

1150

#ifdef __GNUC__

1151

#pragma GCC diagnostic push

1152

#pragma GCC diagnostic ignored "-Wcast-qual"

1153

#endif

1154

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

1155

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

1156

interface, debug ? debug_flag : NULL, NULL },

1157

environ) == -1){

1158

#ifdef __GNUC__

1159

#pragma GCC diagnostic pop

1160

#endif

1161

perror_plus("fexecve");

1162

_exit(EXIT_FAILURE);

1163

}

1164

}

1165

if(pid == -1){

1166

perror_plus("fork");

1167

close(devnull);

1168

return false;

1169

}

1170

ret = close(devnull);

1171

if(ret == -1){

1172

perror_plus("close");

1173

}

1174

int status;

1175

pid_t pret = -1;

1176

errno = 0;

1177

do {

1178

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

1179

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

1180

int errno_raising = 0;

1181

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

1182

errno_raising = errno;

1183

perror_plus("Failed to raise privileges in order to"

1184

" kill helper program");

1185

}

1186

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

1187

perror_plus("kill");

1188

}

1189

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

1190

perror_plus("Failed to lower privileges after killing"

1191

" helper program");

1192

}

1193

return false;

1194

}

1195

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

1196

if(pret == -1){

1197

perror_plus("waitpid");

1198

return false;

1199

}

1200

if(WIFEXITED(status)){

1201

if(WEXITSTATUS(status) != 0){

1202

fprintf_plus(stderr, "Error: iprouteadddel exited"

1203

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

1204

return false;

1205

}

1206

return true;

1207

}

1208

if(WIFSIGNALED(status)){

1209

fprintf_plus(stderr, "Error: iprouteadddel died by"

1210

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

1211

return false;

1212

}

1213

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

1214

return false;

1215

}

1216

1217

__attribute__((nonnull, warn_unused_result))

1218

static bool add_local_route(const char *address,

1219

AvahiIfIndex if_index){

1220

if(debug){

1221

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

1222

}

1223

return add_delete_local_route(true, address, if_index);

1224

}

1225

1226

__attribute__((nonnull, warn_unused_result))

1227

static bool delete_local_route(const char *address,

1228

AvahiIfIndex if_index){

1229

if(debug){

1230

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

1231

}

1232

return add_delete_local_route(false, address, if_index);

1233

}

1234

1235

596

/* Called when a Mandos server is found */

1236

__attribute__((nonnull, warn_unused_result))

1237

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

597

static int start_mandos_communication(const char *ip, uint16_t port,

1238

598

AvahiIfIndex if_index,

1239

int af, mandos_context *mc){

599

int af){

1240

600

int ret, tcp_sd = -1;

1241

601

ssize_t sret;

1242

struct sockaddr_storage to;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

1243

606

char *buffer = NULL;

1244

607

char *decrypted_buffer = NULL;

1245

608

size_t buffer_length = 0;

1248

611

int retval = -1;

1249

612

gnutls_session_t session;

1250

613

int pf; /* Protocol family */

1251

bool route_added = false;

1252

614

1253

615

errno = 0;

1254

616

1265

627

pf = PF_INET;

1266

628

break;

1267

629

default:

1268

fprintf_plus(stderr, "Bad address family: %d\n", af);

630

fprintf(stderr, "Bad address family: %d\n", af);

1269

631

errno = EINVAL;

1270

632

return -1;

1271

633

}

1272

634

1273

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

1274

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

1275

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

1276

bool match = false;

1277

{

1278

char *interface = NULL;

1279

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

1280

mc->interfaces_size,

1281

interface))){

1282

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

1283

match = true;

1284

break;

1285

}

1286

}

1287

}

1288

if(not match){

1289

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

1290

connect to the server */

1291

if(debug){

1292

char interface[IF_NAMESIZE];

1293

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

1294

perror_plus("if_indextoname");

1295

} else {

1296

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

1297

" \"%s\"\n",

1298

if_indextoname((unsigned int)if_index,

1299

interface));

1300

}

1301

}

1302

return -1;

1303

}

1304

}

1305

1306

ret = init_gnutls_session(&session, mc);

635

ret = init_gnutls_session(&session);

1307

636

if(ret != 0){

1308

637

return -1;

1309

638

}

1310

639

1311

640

if(debug){

1312

fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"

1313

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

641

fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16

642

"\n", ip, port);

1314

643

}

1315

644

1316

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

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

1317

646

if(tcp_sd < 0){

1318

647

int e = errno;

1319

648

perror_plus("socket");

1326

655

goto mandos_end;

1327

656

}

1328

657

658

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

1329

659

if(af == AF_INET6){

1330

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

1331

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

1332

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

660

to.in6.sin6_family = (sa_family_t)af;

661

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

1333

662

} else { /* IPv4 */

1334

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

1335

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

1336

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

663

to.in.sin_family = (sa_family_t)af;

664

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

1337

665

}

1338

666

if(ret < 0 ){

1339

667

int e = errno;

1343

671

}

1344

672

if(ret == 0){

1345

673

int e = errno;

1346

fprintf_plus(stderr, "Bad address: %s\n", ip);

674

fprintf(stderr, "Bad address: %s\n", ip);

1347

675

errno = e;

1348

676

goto mandos_end;

1349

677

}

1350

678

if(af == AF_INET6){

1351

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

1352

if(IN6_IS_ADDR_LINKLOCAL

1353

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

679

to.in6.sin6_port = htons(port); /* Spurious warnings from

680

-Wconversion and

681

-Wunreachable-code */

682

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

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

685

-Wunreachable-code*/

1354

686

if(if_index == AVAHI_IF_UNSPEC){

1355

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

1356

" incomplete without a network interface\n");

687

fprintf(stderr, "An IPv6 link-local address is incomplete"

688

" without a network interface\n");

1357

689

errno = EINVAL;

1358

690

goto mandos_end;

1359

691

}

1360

692

/* Set the network interface number as scope */

1361

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

693

to.in6.sin6_scope_id = (uint32_t)if_index;

1362

694

}

1363

695

} else {

1364

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

696

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

697

-Wconversion and

698

-Wunreachable-code */

1365

699

}

1366

700

1367

701

if(quit_now){

1375

709

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

1376

710

perror_plus("if_indextoname");

1377

711

} else {

1378

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX

1379

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

712

fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",

713

ip, interface, port);

1380

714

}

1381

715

} else {

1382

fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",

1383

ip, (uintmax_t)port);

716

fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,

717

port);

1384

718

}

1385

719

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1386

720

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1387

if(af == AF_INET6){

1388

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

1389

sizeof(struct sockaddr_in6),

1390

addrstr, sizeof(addrstr), NULL, 0,

1391

NI_NUMERICHOST);

1392

} else {

1393

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

1394

sizeof(struct sockaddr_in),

1395

addrstr, sizeof(addrstr), NULL, 0,

1396

NI_NUMERICHOST);

1397

}

1398

if(ret == EAI_SYSTEM){

1399

perror_plus("getnameinfo");

1400

} else if(ret != 0) {

1401

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

1402

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

1403

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

1404

}

1405

}

1406

1407

if(quit_now){

1408

errno = EINTR;

1409

goto mandos_end;

1410

}

1411

1412

while(true){

1413

if(af == AF_INET6){

1414

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

1415

sizeof(struct sockaddr_in6));

1416

} else {

1417

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

1418

sizeof(struct sockaddr_in));

1419

}

1420

if(ret < 0){

1421

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

1422

and if_index != AVAHI_IF_UNSPEC

1423

and connect_to == NULL

1424

and not route_added and

1425

((af == AF_INET6 and not

1426

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1427

&to)->sin6_addr)))

1428

or (af == AF_INET and

1429

/* Not a a IPv4LL address */

1430

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

1431

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

1432

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

1433

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

1434

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

1435

connect to a Mandos server announced by Avahi on a server

1436

host with a global address. Work around this by retrying

1437

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

1438

1439

Avahi bug reference:

1440

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

1441

https://bugs.debian.org/587961

1442

*/

1443

if(debug){

1444

fprintf_plus(stderr, "Mandos server unreachable, trying"

1445

" direct route\n");

1446

}

1447

int e = errno;

1448

route_added = add_local_route(ip, if_index);

1449

if(route_added){

1450

continue;

1451

}

1452

errno = e;

1453

}

1454

if(errno != ECONNREFUSED or debug){

1455

int e = errno;

1456

perror_plus("connect");

1457

errno = e;

1458

}

1459

goto mandos_end;

1460

}

1461

1462

if(quit_now){

1463

errno = EINTR;

1464

goto mandos_end;

1465

}

1466

break;

721

const char *pcret;

722

if(af == AF_INET6){

723

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

724

sizeof(addrstr));

725

} else {

726

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

727

sizeof(addrstr));

728

}

729

if(pcret == NULL){

730

perror_plus("inet_ntop");

731

} else {

732

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

733

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

734

}

735

}

736

}

737

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

743

if(af == AF_INET6){

744

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

745

} else {

746

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

747

}

748

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

754

goto mandos_end;

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

1467

760

}

1468

761

1469

762

const char *out = mandos_protocol_version;

1471

764

while(true){

1472

765

size_t out_size = strlen(out);

1473

766

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

1474

out_size - written));

767

out_size - written));

1475

768

if(ret == -1){

1476

769

int e = errno;

1477

770

perror_plus("write");

1497

790

}

1498

791

1499

792

if(debug){

1500

fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);

793

fprintf(stderr, "Establishing TLS session with %s\n", ip);

1501

794

}

1502

795

1503

796

if(quit_now){

1505

798

goto mandos_end;

1506

799

}

1507

800

1508

/* This casting via intptr_t is to eliminate warning about casting

1509

an int to a pointer type. This is exactly how the GnuTLS Guile

1510

function "set-session-transport-fd!" does it. */

1511

gnutls_transport_set_ptr(session,

1512

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

801

/* Spurious warning from -Wint-to-pointer-cast */

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1513

803

1514

804

if(quit_now){

1515

805

errno = EINTR;

1526

816

1527

817

if(ret != GNUTLS_E_SUCCESS){

1528

818

if(debug){

1529

fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");

819

fprintf(stderr, "*** GnuTLS Handshake failed ***\n");

1530

820

gnutls_perror(ret);

1531

821

}

1532

822

errno = EPROTO;

1536

826

/* Read OpenPGP packet that contains the wanted password */

1537

827

1538

828

if(debug){

1539

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1540

" %s\n", ip);

829

fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",

830

ip);

1541

831

}

1542

832

1543

833

while(true){

1548

838

}

1549

839

1550

840

buffer_capacity = incbuffer(&buffer, buffer_length,

1551

buffer_capacity);

841

buffer_capacity);

1552

842

if(buffer_capacity == 0){

1553

843

int e = errno;

1554

844

perror_plus("incbuffer");

1581

871

}

1582

872

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

1583

873

if(ret < 0){

1584

fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "

1585

"***\n");

874

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

1586

875

gnutls_perror(ret);

1587

876

errno = EPROTO;

1588

877

goto mandos_end;

1589

878

}

1590

879

break;

1591

880

default:

1592

fprintf_plus(stderr, "Unknown error while reading data from"

1593

" encrypted session with Mandos server\n");

881

fprintf(stderr, "Unknown error while reading data from"

882

" encrypted session with Mandos server\n");

1594

883

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1595

884

errno = EIO;

1596

885

goto mandos_end;

1601

890

}

1602

891

1603

892

if(debug){

1604

fprintf_plus(stderr, "Closing TLS session\n");

893

fprintf(stderr, "Closing TLS session\n");

1605

894

}

1606

895

1607

896

if(quit_now){

1619

908

1620

909

if(buffer_length > 0){

1621

910

ssize_t decrypted_buffer_size;

1622

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1623

&decrypted_buffer, mc);

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

1624

914

if(decrypted_buffer_size >= 0){

1625

915

1626

clearerr(stdout);

1627

916

written = 0;

1628

917

while(written < (size_t) decrypted_buffer_size){

1629

918

if(quit_now){

1637

926

if(ret == 0 and ferror(stdout)){

1638

927

int e = errno;

1639

928

if(debug){

1640

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

1641

strerror(errno));

929

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

930

strerror(errno));

1642

931

}

1643

932

errno = e;

1644

933

goto mandos_end;

1645

934

}

1646

935

written += (size_t)ret;

1647

936

}

1648

ret = fflush(stdout);

1649

if(ret != 0){

1650

int e = errno;

1651

if(debug){

1652

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

1653

strerror(errno));

1654

}

1655

errno = e;

1656

goto mandos_end;

1657

}

1658

937

retval = 0;

1659

938

}

1660

939

}

1663

942

1664

943

mandos_end:

1665

944

{

1666

if(route_added){

1667

if(not delete_local_route(ip, if_index)){

1668

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

1669

" interface %d", ip, if_index);

1670

}

1671

}

1672

945

int e = errno;

1673

946

free(decrypted_buffer);

1674

947

free(buffer);

1675

948

if(tcp_sd >= 0){

1676

ret = close(tcp_sd);

949

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

1677

950

}

1678

951

if(ret == -1){

1679

952

if(e == 0){

1704

977

AVAHI_GCC_UNUSED AvahiStringList *txt,

1705

978

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1706

979

flags,

1707

void *mc){

1708

if(r == NULL){

1709

return;

1710

}

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1711

982

1712

983

/* Called whenever a service has been resolved successfully or

1713

984

timed out */

1714

985

1715

986

if(quit_now){

1716

avahi_s_service_resolver_free(r);

1717

987

return;

1718

988

}

1719

989

1720

990

switch(event){

1721

991

default:

1722

992

case AVAHI_RESOLVER_FAILURE:

1723

fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "

1724

"'%s' of type '%s' in domain '%s': %s\n", name, type,

1725

domain,

1726

avahi_strerror(avahi_server_errno

1727

(((mandos_context*)mc)->server)));

993

fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"

994

" of type '%s' in domain '%s': %s\n", name, type, domain,

995

avahi_strerror(avahi_server_errno(mc.server)));

1728

996

break;

1729

997

1730

998

case AVAHI_RESOLVER_FOUND:

1732

1000

char ip[AVAHI_ADDRESS_STR_MAX];

1733

1001

avahi_address_snprint(ip, sizeof(ip), address);

1734

1002

if(debug){

1735

fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"

1736

PRIdMAX ") on port %" PRIu16 "\n", name,

1737

host_name, ip, (intmax_t)interface, port);

1003

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"

1004

PRIdMAX ") on port %" PRIu16 "\n", name, host_name,

1005

ip, (intmax_t)interface, port);

1738

1006

}

1739

int ret = start_mandos_communication(ip, (in_port_t)port,

1740

interface,

1741

avahi_proto_to_af(proto),

1742

mc);

1007

int ret = start_mandos_communication(ip, port, interface,

1008

avahi_proto_to_af(proto));

1743

1009

if(ret == 0){

1744

avahi_simple_poll_quit(simple_poll);

1010

avahi_simple_poll_quit(mc.simple_poll);

1745

1011

} else {

1746

if(not add_server(ip, (in_port_t)port, interface,

1747

avahi_proto_to_af(proto),

1748

&((mandos_context*)mc)->current_server)){

1749

fprintf_plus(stderr, "Failed to add server \"%s\" to server"

1750

" list\n", name);

1751

}

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1752

1014

}

1753

1015

}

1754

1016

}

1764

1026

const char *domain,

1765

1027

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1766

1028

flags,

1767

void *mc){

1768

if(b == NULL){

1769

return;

1770

}

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1771

1031

1772

1032

/* Called whenever a new services becomes available on the LAN or

1773

1033

is removed from the LAN */

1780

1040

default:

1781

1041

case AVAHI_BROWSER_FAILURE:

1782

1042

1783

fprintf_plus(stderr, "(Avahi browser) %s\n",

1784

avahi_strerror(avahi_server_errno

1785

(((mandos_context*)mc)->server)));

1786

avahi_simple_poll_quit(simple_poll);

1043

fprintf(stderr, "(Avahi browser) %s\n",

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1787

1046

return;

1788

1047

1789

1048

case AVAHI_BROWSER_NEW:

1792

1051

the callback function is called the Avahi server will free the

1793

1052

resolver for us. */

1794

1053

1795

if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,

1796

interface, protocol, name, type,

1797

domain, protocol, 0,

1798

resolve_callback, mc) == NULL)

1799

fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"

1800

" %s\n", name,

1801

avahi_strerror(avahi_server_errno

1802

(((mandos_context*)mc)->server)));

1054

if(avahi_s_service_resolver_new(mc.server, interface, protocol,

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",

1058

name, avahi_strerror(avahi_server_errno(mc.server)));

1803

1059

break;

1804

1060

1805

1061

case AVAHI_BROWSER_REMOVE:

1808

1064

case AVAHI_BROWSER_ALL_FOR_NOW:

1809

1065

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1810

1066

if(debug){

1811

fprintf_plus(stderr, "No Mandos server found, still"

1812

" searching...\n");

1067

fprintf(stderr, "No Mandos server found, still searching...\n");

1813

1068

}

1814

1069

break;

1815

1070

}

1824

1079

signal_received = sig;

1825

1080

int old_errno = errno;

1826

1081

/* set main loop to exit */

1827

if(simple_poll != NULL){

1828

avahi_simple_poll_quit(simple_poll);

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1829

1084

}

1830

1085

errno = old_errno;

1831

1086

}

1832

1087

1833

__attribute__((nonnull, warn_unused_result))

1834

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

1835

int ret;

1836

int old_errno;

1837

1838

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

1839

if(s < 0){

1840

old_errno = errno;

1841

perror_plus("socket");

1842

errno = old_errno;

1843

return false;

1844

}

1845

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

1846

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

1847

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1848

if(ret == -1){

1088

/*

1089

* This function determines if a directory entry in /sys/class/net

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1116

flagstring[(size_t)to_read] = '\0';

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

tmpmax = strtoimax(flagstring, &tmp, 0);

1141

if(errno != 0 or tmp == flagstring or (*tmp != '\0'

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1849

1144

if(debug){

1850

old_errno = errno;

1851

perror_plus("ioctl SIOCGIFFLAGS");

1852

errno = old_errno;

1853

}

1854

if((close(s) == -1) and debug){

1855

old_errno = errno;

1856

perror_plus("close");

1857

errno = old_errno;

1858

}

1859

return false;

1860

}

1861

if((close(s) == -1) and debug){

1862

old_errno = errno;

1863

perror_plus("close");

1864

errno = old_errno;

1865

}

1866

return true;

1867

}

1868

1869

__attribute__((nonnull, warn_unused_result))

1870

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

1871

1145

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1872

1153

/* Reject the loopback device */

1873

if(ifr->ifr_flags & IFF_LOOPBACK){

1154

if(flags & IFF_LOOPBACK){

1874

1155

if(debug){

1875

fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",

1876

ifname);

1156

fprintf(stderr, "Rejecting loopback interface \"%s\"\n",

1157

if_entry->d_name);

1877

1158

}

1878

return false;

1159

return 0;

1879

1160

}

1880

1161

/* Accept point-to-point devices only if connect_to is specified */

1881

if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){

1162

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1882

1163

if(debug){

1883

fprintf_plus(stderr, "Accepting point-to-point interface"

1884

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

1164

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1165

if_entry->d_name);

1885

1166

}

1886

return true;

1167

return 1;

1887

1168

}

1888

1169

/* Otherwise, reject non-broadcast-capable devices */

1889

if(not (ifr->ifr_flags & IFF_BROADCAST)){

1170

if(not (flags & IFF_BROADCAST)){

1890

1171

if(debug){

1891

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1892

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

1172

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1173

if_entry->d_name);

1893

1174

}

1894

return false;

1175

return 0;

1895

1176

}

1896

1177

/* Reject non-ARP interfaces (including dummy interfaces) */

1897

if(ifr->ifr_flags & IFF_NOARP){

1178

if(flags & IFF_NOARP){

1898

1179

if(debug){

1899

fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",

1900

ifname);

1180

fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",

1181

if_entry->d_name);

1901

1182

}

1902

return false;

1183

return 0;

1903

1184

}

1904

1905

1185

/* Accept this device */

1906

1186

if(debug){

1907

fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);

1908

}

1909

return true;

1910

}

1911

1912

/*

1913

* This function determines if a directory entry in /sys/class/net

1914

* corresponds to an acceptable network device.

1915

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

1916

*/

1917

__attribute__((nonnull, warn_unused_result))

1918

int good_interface(const struct dirent *if_entry){

1919

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

1920

return 0;

1921

}

1922

1923

struct ifreq ifr;

1924

if(not get_flags(if_entry->d_name, &ifr)){

1925

if(debug){

1926

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

1927

"\"%s\"\n", if_entry->d_name);

1928

}

1929

return 0;

1930

}

1931

1932

if(not good_flags(if_entry->d_name, &ifr)){

1933

return 0;

1187

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1188

if_entry->d_name);

1934

1189

}

1935

1190

return 1;

1936

1191

}

1937

1192

1938

/*

1939

* This function determines if a network interface is up.

1940

*/

1941

__attribute__((nonnull, warn_unused_result))

1942

bool interface_is_up(const char *interface){

1943

struct ifreq ifr;

1944

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

1945

if(debug){

1946

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

1947

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

1948

}

1949

return false;

1950

}

1951

1952

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

1953

}

1954

1955

/*

1956

* This function determines if a network interface is running

1957

*/

1958

__attribute__((nonnull, warn_unused_result))

1959

bool interface_is_running(const char *interface){

1960

struct ifreq ifr;

1961

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

1962

if(debug){

1963

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

1964

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

1965

}

1966

return false;

1967

}

1968

1969

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

1970

}

1971

1972

__attribute__((nonnull, pure, warn_unused_result))

1973

1193

int notdotentries(const struct dirent *direntry){

1974

1194

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

1975

1195

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

1981

1201

return 1;

1982

1202

}

1983

1203

1984

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

1985

__attribute__((nonnull, warn_unused_result))

1986

int runnable_hook(const struct dirent *direntry){

1987

int ret;

1988

size_t sret;

1989

struct stat st;

1990

1991

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

1992

/* Empty name? */

1993

return 0;

1994

}

1995

1996

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

1997

"abcdefghijklmnopqrstuvwxyz"

1998

"0123456789"

1999

"_.-");

2000

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

2001

/* Contains non-allowed characters */

2002

if(debug){

2003

fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",

2004

direntry->d_name);

2005

}

2006

return 0;

2007

}

2008

2009

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

2010

if(ret == -1){

2011

if(debug){

2012

perror_plus("Could not stat hook");

2013

}

2014

return 0;

2015

}

2016

if(not (S_ISREG(st.st_mode))){

2017

/* Not a regular file */

2018

if(debug){

2019

fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",

2020

direntry->d_name);

2021

}

2022

return 0;

2023

}

2024

if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){

2025

/* Not executable */

2026

if(debug){

2027

fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",

2028

direntry->d_name);

2029

}

2030

return 0;

2031

}

2032

if(debug){

2033

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

2034

direntry->d_name);

2035

}

2036

return 1;

2037

}

2038

2039

__attribute__((nonnull, warn_unused_result))

2040

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2041

mandos_context *mc){

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2042

1205

int ret;

2043

1206

struct timespec now;

2044

1207

struct timespec waited_time;

2045

1208

intmax_t block_time;

2046

1209

2047

1210

while(true){

2048

if(mc->current_server == NULL){

2049

if(debug){

2050

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

2051

" No timeout!\n");

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

"Wait until first server is found. No timeout!\n");

2052

1215

}

2053

1216

ret = avahi_simple_poll_iterate(s, -1);

2054

1217

} else {

2055

if(debug){

2056

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

2057

" it, or wait\n");

1218

if (debug){

1219

fprintf(stderr, "Check current_server if we should run it,"

1220

" or wait\n");

2058

1221

}

2059

1222

/* the current time */

2060

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

2065

1228

/* Calculating in ms how long time between now and server

2066

1229

who we visted longest time ago. Now - last seen. */

2067

1230

waited_time.tv_sec = (now.tv_sec

2068

- mc->current_server->last_seen.tv_sec);

1231

- mc.current_server->last_seen.tv_sec);

2069

1232

waited_time.tv_nsec = (now.tv_nsec

2070

- mc->current_server->last_seen.tv_nsec);

1233

- mc.current_server->last_seen.tv_nsec);

2071

1234

/* total time is 10s/10,000ms.

2072

1235

Converting to s from ms by dividing by 1,000,

2073

1236

and ns to ms by dividing by 1,000,000. */

2075

1238

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

2076

1239

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

2077

1240

2078

if(debug){

2079

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

2080

block_time);

1241

if (debug){

1242

fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);

2081

1243

}

2082

1244

2083

1245

if(block_time <= 0){

2084

ret = start_mandos_communication(mc->current_server->ip,

2085

mc->current_server->port,

2086

mc->current_server->if_index,

2087

mc->current_server->af, mc);

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

2088

1250

if(ret == 0){

2089

avahi_simple_poll_quit(s);

1251

avahi_simple_poll_quit(mc.simple_poll);

2090

1252

return 0;

2091

1253

}

2092

1254

ret = clock_gettime(CLOCK_MONOTONIC,

2093

&mc->current_server->last_seen);

1255

&mc.current_server->last_seen);

2094

1256

if(ret == -1){

2095

1257

perror_plus("clock_gettime");

2096

1258

return -1;

2097

1259

}

2098

mc->current_server = mc->current_server->next;

1260

mc.current_server = mc.current_server->next;

2099

1261

block_time = 0; /* Call avahi to find new Mandos

2100

1262

servers, but don't block */

2101

1263

}

2103

1265

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

2104

1266

}

2105

1267

if(ret != 0){

2106

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

1268

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

2107

1269

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

2108

1270

}

2109

1271

}

2110

1272

}

2111

1273

}

2112

1274

2113

__attribute__((nonnull))

2114

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

2115

const float delay){

2116

struct dirent **direntries = NULL;

2117

if(hookdir_fd == -1){

2118

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2119

| O_CLOEXEC);

2120

if(hookdir_fd == -1){

2121

if(errno == ENOENT){

2122

if(debug){

2123

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

2124

" found\n", hookdir);

2125

}

2126

} else {

2127

perror_plus("open");

2128

}

2129

return;

2130

}

2131

}

2132

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

2133

if(devnull == -1){

2134

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

2135

return;

2136

}

2137

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

2138

runnable_hook, alphasort);

2139

if(numhooks == -1){

2140

perror_plus("scandir");

2141

close(devnull);

2142

return;

2143

}

2144

struct dirent *direntry;

2145

int ret;

2146

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

2147

direntry = direntries[i];

2148

if(debug){

2149

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

2150

direntry->d_name);

2151

}

2152

pid_t hook_pid = fork();

2153

if(hook_pid == 0){

2154

/* Child */

2155

/* Raise privileges */

2156

errno = raise_privileges_permanently();

2157

if(errno != 0){

2158

perror_plus("Failed to raise privileges");

2159

_exit(EX_NOPERM);

2160

}

2161

/* Set group */

2162

errno = 0;

2163

ret = setgid(0);

2164

if(ret == -1){

2165

perror_plus("setgid");

2166

_exit(EX_NOPERM);

2167

}

2168

/* Reset supplementary groups */

2169

errno = 0;

2170

ret = setgroups(0, NULL);

2171

if(ret == -1){

2172

perror_plus("setgroups");

2173

_exit(EX_NOPERM);

2174

}

2175

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

2176

if(ret == -1){

2177

perror_plus("setenv");

2178

_exit(EX_OSERR);

2179

}

2180

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

2181

if(ret == -1){

2182

perror_plus("setenv");

2183

_exit(EX_OSERR);

2184

}

2185

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

2186

if(ret == -1){

2187

perror_plus("setenv");

2188

_exit(EX_OSERR);

2189

}

2190

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

2191

if(ret == -1){

2192

perror_plus("setenv");

2193

_exit(EX_OSERR);

2194

}

2195

char *delaystring;

2196

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

2197

if(ret == -1){

2198

perror_plus("asprintf");

2199

_exit(EX_OSERR);

2200

}

2201

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

2202

if(ret == -1){

2203

free(delaystring);

2204

perror_plus("setenv");

2205

_exit(EX_OSERR);

2206

}

2207

free(delaystring);

2208

if(connect_to != NULL){

2209

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

2210

if(ret == -1){

2211

perror_plus("setenv");

2212

_exit(EX_OSERR);

2213

}

2214

}

2215

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

2216

direntry->d_name,

2217

O_RDONLY));

2218

if(hook_fd == -1){

2219

perror_plus("openat");

2220

_exit(EXIT_FAILURE);

2221

}

2222

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

2223

perror_plus("close");

2224

_exit(EXIT_FAILURE);

2225

}

2226

ret = dup2(devnull, STDIN_FILENO);

2227

if(ret == -1){

2228

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

2229

_exit(EX_OSERR);

2230

}

2231

ret = close(devnull);

2232

if(ret == -1){

2233

perror_plus("close");

2234

_exit(EX_OSERR);

2235

}

2236

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2237

if(ret == -1){

2238

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

2239

_exit(EX_OSERR);

2240

}

2241

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

2242

environ) == -1){

2243

perror_plus("fexecve");

2244

_exit(EXIT_FAILURE);

2245

}

2246

} else {

2247

if(hook_pid == -1){

2248

perror_plus("fork");

2249

free(direntry);

2250

continue;

2251

}

2252

int status;

2253

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

2254

perror_plus("waitpid");

2255

free(direntry);

2256

continue;

2257

}

2258

if(WIFEXITED(status)){

2259

if(WEXITSTATUS(status) != 0){

2260

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

2261

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

2262

WEXITSTATUS(status));

2263

free(direntry);

2264

continue;

2265

}

2266

} else if(WIFSIGNALED(status)){

2267

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

2268

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

2269

WTERMSIG(status));

2270

free(direntry);

2271

continue;

2272

} else {

2273

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

2274

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

2275

free(direntry);

2276

continue;

2277

}

2278

}

2279

if(debug){

2280

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

2281

direntry->d_name);

2282

}

2283

free(direntry);

2284

}

2285

free(direntries);

2286

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

2287

perror_plus("close");

2288

} else {

2289

hookdir_fd = -1;

2290

}

2291

close(devnull);

2292

}

2293

2294

__attribute__((nonnull, warn_unused_result))

2295

int bring_up_interface(const char *const interface,

2296

const float delay){

2297

int old_errno = errno;

2298

int ret;

2299

struct ifreq network;

2300

unsigned int if_index = if_nametoindex(interface);

2301

if(if_index == 0){

2302

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

2303

errno = old_errno;

2304

return ENXIO;

2305

}

2306

2307

if(quit_now){

2308

errno = old_errno;

2309

return EINTR;

2310

}

2311

2312

if(not interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

2316

ret_errno = errno;

2317

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

2318

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

2319

errno = old_errno;

2320

return ret_errno;

2321

}

2322

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

2323

2324

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

2325

if(sd == -1){

2326

ret_errno = errno;

2327

perror_plus("socket");

2328

errno = old_errno;

2329

return ret_errno;

2330

}

2331

2332

if(quit_now){

2333

ret = close(sd);

2334

if(ret == -1){

2335

perror_plus("close");

2336

}

2337

errno = old_errno;

2338

return EINTR;

2339

}

2340

2341

if(debug){

2342

fprintf_plus(stderr, "Bringing up interface \"%s\"\n",

2343

interface);

2344

}

2345

2346

/* Raise privileges */

2347

ret_errno = raise_privileges();

2348

if(ret_errno != 0){

2349

errno = ret_errno;

2350

perror_plus("Failed to raise privileges");

2351

}

2352

2353

#ifdef __linux__

2354

int ret_linux;

2355

bool restore_loglevel = false;

2356

if(ret_errno == 0){

2357

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2358

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

2359

ret_linux = klogctl(8, NULL, 5);

2360

if(ret_linux == -1){

2361

perror_plus("klogctl");

2362

} else {

2363

restore_loglevel = true;

2364

}

2365

}

2366

#endif /* __linux__ */

2367

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

2368

ioctl_errno = errno;

2369

#ifdef __linux__

2370

if(restore_loglevel){

2371

ret_linux = klogctl(7, NULL, 0);

2372

if(ret_linux == -1){

2373

perror_plus("klogctl");

2374

}

2375

}

2376

#endif /* __linux__ */

2377

2378

/* If raise_privileges() succeeded above */

2379

if(ret_errno == 0){

2380

/* Lower privileges */

2381

ret_errno = lower_privileges();

2382

if(ret_errno != 0){

2383

errno = ret_errno;

2384

perror_plus("Failed to lower privileges");

2385

}

2386

}

2387

2388

/* Close the socket */

2389

ret = close(sd);

2390

if(ret == -1){

2391

perror_plus("close");

2392

}

2393

2394

if(ret_setflags == -1){

2395

errno = ioctl_errno;

2396

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2397

errno = old_errno;

2398

return ioctl_errno;

2399

}

2400

} else if(debug){

2401

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

2402

interface);

2403

}

2404

2405

/* Sleep checking until interface is running.

2406

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

2407

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

2408

if(interface_is_running(interface)){

2409

break;

2410

}

2411

struct timespec sleeptime = { .tv_nsec = 250000000 };

2412

ret = nanosleep(&sleeptime, NULL);

2413

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

2414

perror_plus("nanosleep");

2415

}

2416

}

2417

2418

errno = old_errno;

2419

return 0;

2420

}

2421

2422

__attribute__((nonnull, warn_unused_result))

2423

int take_down_interface(const char *const interface){

2424

int old_errno = errno;

2425

struct ifreq network;

2426

unsigned int if_index = if_nametoindex(interface);

2427

if(if_index == 0){

2428

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

2429

errno = old_errno;

2430

return ENXIO;

2431

}

2432

if(interface_is_up(interface)){

2433

int ret_errno = 0;

2434

int ioctl_errno = 0;

2435

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

2436

ret_errno = errno;

2437

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

2438

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

2439

errno = old_errno;

2440

return ret_errno;

2441

}

2442

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

2443

2444

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

2445

if(sd == -1){

2446

ret_errno = errno;

2447

perror_plus("socket");

2448

errno = old_errno;

2449

return ret_errno;

2450

}

2451

2452

if(debug){

2453

fprintf_plus(stderr, "Taking down interface \"%s\"\n",

2454

interface);

2455

}

2456

2457

/* Raise privileges */

2458

ret_errno = raise_privileges();

2459

if(ret_errno != 0){

2460

errno = ret_errno;

2461

perror_plus("Failed to raise privileges");

2462

}

2463

2464

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

2465

ioctl_errno = errno;

2466

2467

/* If raise_privileges() succeeded above */

2468

if(ret_errno == 0){

2469

/* Lower privileges */

2470

ret_errno = lower_privileges();

2471

if(ret_errno != 0){

2472

errno = ret_errno;

2473

perror_plus("Failed to lower privileges");

2474

}

2475

}

2476

2477

/* Close the socket */

2478

int ret = close(sd);

2479

if(ret == -1){

2480

perror_plus("close");

2481

}

2482

2483

if(ret_setflags == -1){

2484

errno = ioctl_errno;

2485

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2486

errno = old_errno;

2487

return ioctl_errno;

2488

}

2489

} else if(debug){

2490

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

2491

interface);

2492

}

2493

2494

errno = old_errno;

2495

return 0;

2496

}

2497

2498

1275

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

2499

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

2500

#if GNUTLS_VERSION_NUMBER >= 0x030606

2501

.priority = "SECURE128:!CTYPE-X.509"

2502

":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"

2503

":%PROFILE_ULTRA",

2504

#elif GNUTLS_VERSION_NUMBER < 0x030600

2505

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

2506

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

2507

#else

2508

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

2509

#endif

2510

.current_server = NULL, .interfaces = NULL,

2511

.interfaces_size = 0 };

2512

1276

AvahiSServiceBrowser *sb = NULL;

2513

error_t ret_errno;

1277

int error;

2514

1278

int ret;

2515

1279

intmax_t tmpmax;

2516

1280

char *tmp;

2517

1281

int exitcode = EXIT_SUCCESS;

2518

char *interfaces_to_take_down = NULL;

2519

size_t interfaces_to_take_down_size = 0;

2520

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

2521

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

2522

char *tempdir = NULL;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1288

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

1289

bool tempdir_created = false;

2523

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2524

1291

const char *seckey = PATHDIR "/" SECKEY;

2525

1292

const char *pubkey = PATHDIR "/" PUBKEY;

2526

#if GNUTLS_VERSION_NUMBER >= 0x030606

2527

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2528

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2529

#endif

2530

const char *dh_params_file = NULL;

2531

char *interfaces_hooks = NULL;

2532

1293

2533

1294

bool gnutls_initialized = false;

2534

1295

bool gpgme_initialized = false;

2580

1341

{ .name = "pubkey", .key = 'p',

2581

1342

.arg = "FILE",

2582

1343

.doc = "OpenPGP public key file base name",

2583

.group = 1 },

2584

{ .name = "tls-privkey", .key = 't',

2585

.arg = "FILE",

2586

#if GNUTLS_VERSION_NUMBER >= 0x030606

2587

.doc = "TLS private key file base name",

2588

#else

2589

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2590

#endif

2591

.group = 1 },

2592

{ .name = "tls-pubkey", .key = 'T',

2593

.arg = "FILE",

2594

#if GNUTLS_VERSION_NUMBER >= 0x030606

2595

.doc = "TLS public key file base name",

2596

#else

2597

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2598

#endif

2599

.group = 1 },

1344

.group = 2 },

2600

1345

{ .name = "dh-bits", .key = 129,

2601

1346

.arg = "BITS",

2602

1347

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

2603

1348

" Diffie-Hellman key exchange",

2604

1349

.group = 2 },

2605

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

2606

.arg = "FILE",

2607

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

2608

" for the Diffie-Hellman key exchange",

2609

.group = 2 },

2610

1350

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

2611

1351

.arg = "STRING",

2612

1352

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

2617

1357

.group = 2 },

2618

1358

{ .name = "retry", .key = 132,

2619

1359

.arg = "SECONDS",

2620

.doc = "Retry interval used when denied by the Mandos server",

2621

.group = 2 },

2622

{ .name = "network-hook-dir", .key = 133,

2623

.arg = "DIR",

2624

.doc = "Directory where network hooks are located",

1360

.doc = "Retry interval used when denied by the mandos server",

2625

1361

.group = 2 },

2626

1362

/*

2627

1363

* These reproduce what we would get without ARGP_NO_HELP

2646

1382

connect_to = arg;

2647

1383

break;

2648

1384

case 'i': /* --interface */

2649

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

2650

arg, (int)',');

2651

if(ret_errno != 0){

2652

argp_error(state, "%s", strerror(ret_errno));

2653

}

1385

interface = arg;

2654

1386

break;

2655

1387

case 's': /* --seckey */

2656

1388

seckey = arg;

2658

1390

case 'p': /* --pubkey */

2659

1391

pubkey = arg;

2660

1392

break;

2661

case 't': /* --tls-privkey */

2662

#if GNUTLS_VERSION_NUMBER >= 0x030606

2663

tls_privkey = arg;

2664

#endif

2665

break;

2666

case 'T': /* --tls-pubkey */

2667

#if GNUTLS_VERSION_NUMBER >= 0x030606

2668

tls_pubkey = arg;

2669

#endif

2670

break;

2671

1393

case 129: /* --dh-bits */

2672

1394

errno = 0;

2673

1395

tmpmax = strtoimax(arg, &tmp, 10);

2677

1399

}

2678

1400

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

2679

1401

break;

2680

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

2681

dh_params_file = arg;

2682

break;

2683

1402

case 130: /* --priority */

2684

1403

mc.priority = arg;

2685

1404

break;

2698

1417

argp_error(state, "Bad retry interval");

2699

1418

}

2700

1419

break;

2701

case 133: /* --network-hook-dir */

2702

hookdir = arg;

2703

break;

2704

1420

/*

2705

1421

* These reproduce what we would get without ARGP_NO_HELP

2706

1422

*/

2708

1424

argp_state_help(state, state->out_stream,

2709

1425

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2710

1426

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2711

__builtin_unreachable();

2712

1427

case -3: /* --usage */

2713

1428

argp_state_help(state, state->out_stream,

2714

1429

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2715

__builtin_unreachable();

2716

1430

case 'V': /* --version */

2717

fprintf_plus(state->out_stream, "%s\n", argp_program_version);

1431

fprintf(state->out_stream, "%s\n", argp_program_version);

2718

1432

exit(argp_err_exit_status);

2719

1433

break;

2720

1434

default:

2727

1441

.args_doc = "",

2728

1442

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

2729

1443

" passwords from a Mandos server" };

2730

ret_errno = argp_parse(&argp, argc, argv,

2731

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2732

switch(ret_errno){

1444

ret = argp_parse(&argp, argc, argv,

1445

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1446

switch(ret){

2733

1447

case 0:

2734

1448

break;

2735

1449

case ENOMEM:

2736

1450

default:

2737

errno = ret_errno;

1451

errno = ret;

2738

1452

perror_plus("argp_parse");

2739

1453

exitcode = EX_OSERR;

2740

1454

goto end;

2743

1457

goto end;

2744

1458

}

2745

1459

}

2746

2747

{

2748

/* Re-raise privileges */

2749

ret = raise_privileges();

2750

if(ret != 0){

2751

errno = ret;

2752

perror_plus("Failed to raise privileges");

2753

} else {

2754

struct stat st;

2755

2756

/* Work around Debian bug #633582:

2757

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

2758

2759

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

2760

int seckey_fd = open(seckey, O_RDONLY);

2761

if(seckey_fd == -1){

2762

perror_plus("open");

2763

} else {

2764

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

2765

if(ret == -1){

2766

perror_plus("fstat");

2767

} else {

2768

if(S_ISREG(st.st_mode)

2769

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

2770

ret = fchown(seckey_fd, uid, gid);

2771

if(ret == -1){

2772

perror_plus("fchown");

2773

}

2774

}

2775

}

2776

close(seckey_fd);

2777

}

2778

}

2779

2780

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

2781

int pubkey_fd = open(pubkey, O_RDONLY);

2782

if(pubkey_fd == -1){

2783

perror_plus("open");

2784

} else {

2785

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

2786

if(ret == -1){

2787

perror_plus("fstat");

2788

} else {

2789

if(S_ISREG(st.st_mode)

2790

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

2791

ret = fchown(pubkey_fd, uid, gid);

2792

if(ret == -1){

2793

perror_plus("fchown");

2794

}

2795

}

2796

}

2797

close(pubkey_fd);

2798

}

2799

}

2800

2801

if(dh_params_file != NULL

2802

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

2803

int dhparams_fd = open(dh_params_file, O_RDONLY);

2804

if(dhparams_fd == -1){

2805

perror_plus("open");

2806

} else {

2807

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

2808

if(ret == -1){

2809

perror_plus("fstat");

2810

} else {

2811

if(S_ISREG(st.st_mode)

2812

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

2813

ret = fchown(dhparams_fd, uid, gid);

2814

if(ret == -1){

2815

perror_plus("fchown");

2816

}

2817

}

2818

}

2819

close(dhparams_fd);

2820

}

2821

}

2822

2823

/* Work around Debian bug #981302

2824

<https://bugs.debian.org/981302> */

2825

if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){

2826

ret = symlink("/proc/self/fd", "/dev/fd");

2827

if(ret == -1){

2828

perror_plus("Failed to create /dev/fd symlink");

2829

}

2830

}

2831

2832

/* Lower privileges */

2833

ret = lower_privileges();

2834

if(ret != 0){

2835

errno = ret;

2836

perror_plus("Failed to lower privileges");

2837

}

2838

}

2839

}

2840

2841

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

2842

{

2843

char *interface = NULL;

2844

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

2845

interface))){

2846

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

2847

and if_nametoindex(interface) == 0){

2848

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

2849

fprintf_plus(stderr, "Not using nonexisting interface"

2850

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

2851

}

2852

argz_delete(&mc.interfaces, &mc.interfaces_size, interface);

2853

interface = NULL;

2854

}

2855

}

2856

}

2857

2858

/* Run network hooks */

2859

{

2860

if(mc.interfaces != NULL){

2861

interfaces_hooks = malloc(mc.interfaces_size);

2862

if(interfaces_hooks == NULL){

2863

perror_plus("malloc");

2864

goto end;

2865

}

2866

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

2867

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

2868

}

2869

run_network_hooks("start", interfaces_hooks != NULL ?

2870

interfaces_hooks : "", delay);

1460

1461

{

1462

/* Work around Debian bug #633582:

1463

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

2871

1519

}

2872

1520

2873

1521

if(not debug){

2874

1522

avahi_set_log_function(empty_log);

2875

1523

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

interface = strdup(direntries[0]->d_name);

1532

if(debug){

1533

fprintf(stderr, "Using interface \"%s\"\n", interface);

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

2876

1549

2877

1550

/* Initialize Avahi early so avahi_simple_poll_quit() can be called

2878

1551

from the signal handler */

2879

1552

/* Initialize the pseudo-RNG for Avahi */

2880

1553

srand((unsigned int) time(NULL));

2881

simple_poll = avahi_simple_poll_new();

2882

if(simple_poll == NULL){

2883

fprintf_plus(stderr,

2884

"Avahi: Failed to create simple poll object.\n");

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

2885

1557

exitcode = EX_UNAVAILABLE;

2886

1558

goto end;

2887

1559

}

2949

1621

}

2950

1622

}

2951

1623

2952

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

2953

if(mc.interfaces == NULL){

2954

struct dirent **direntries = NULL;

2955

/* Look for any good interfaces */

2956

ret = scandir(sys_class_net, &direntries, good_interface,

2957

alphasort);

2958

if(ret >= 1){

2959

/* Add all found interfaces to interfaces list */

2960

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

2961

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

2962

direntries[i]->d_name);

2963

if(ret_errno != 0){

2964

errno = ret_errno;

2965

perror_plus("argz_add");

2966

free(direntries[i]);

2967

continue;

2968

}

2969

if(debug){

2970

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

2971

direntries[i]->d_name);

2972

}

2973

free(direntries[i]);

2974

}

2975

free(direntries);

1624

/* If the interface is down, bring it up */

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

fprintf(stderr, "No such interface: \"%s\"\n", interface);

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

if((network.ifr_flags & IFF_UP) == 0){

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

1709

}

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

break;

1729

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

/* We won't need the socket anymore */

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

2976

1760

} else {

2977

if(ret == 0){

2978

free(direntries);

2979

}

2980

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

2981

exitcode = EXIT_FAILURE;

2982

goto end;

2983

}

2984

}

2985

2986

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

2987

{

2988

char *interface = NULL;

2989

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

2990

interface))){

2991

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

2992

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

2993

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

2994

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

2995

interface);

2996

interface = NULL;

2997

while((interface = argz_next(mc.interfaces,

2998

mc.interfaces_size, interface))){

2999

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

3000

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

3001

interface);

3002

interface = NULL;

3003

}

3004

}

3005

break;

3006

}

3007

bool interface_was_up = interface_is_up(interface);

3008

errno = bring_up_interface(interface, delay);

3009

if(not interface_was_up){

3010

if(errno != 0){

3011

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

3012

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

3013

} else {

3014

errno = argz_add(&interfaces_to_take_down,

3015

&interfaces_to_take_down_size,

3016

interface);

3017

if(errno != 0){

3018

perror_plus("argz_add");

3019

}

3020

}

3021

}

3022

}

3023

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

3024

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

3025

}

3026

}

3027

3028

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

3029

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

3030

if(debug){

3031

fprintf_plus(stderr, "Using only interface \"%s\"\n",

3032

mc.interfaces);

3033

}

3034

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

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

3035

1767

}

3036

1768

3037

1769

if(quit_now){

3038

1770

goto end;

3039

1771

}

3040

1772

3041

#if GNUTLS_VERSION_NUMBER >= 0x030606

3042

ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);

3043

#elif GNUTLS_VERSION_NUMBER < 0x030600

3044

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

3045

#else

3046

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

3047

#endif

1773

ret = init_gnutls_global(pubkey, seckey);

3048

1774

if(ret == -1){

3049

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

1775

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

3050

1776

exitcode = EX_UNAVAILABLE;

3051

1777

goto end;

3052

1778

} else {

3057

1783

goto end;

3058

1784

}

3059

1785

3060

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

3061

tempdir = mkdtemp(run_tempdir);

3062

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

3063

if(debug){

3064

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

3065

run_tempdir, old_tempdir);

3066

}

3067

tempdir = mkdtemp(old_tempdir);

3068

}

3069

if(tempdir == NULL){

1786

if(mkdtemp(tempdir) == NULL){

3070

1787

perror_plus("mkdtemp");

3071

1788

goto end;

3072

1789

}

1790

tempdir_created = true;

3073

1791

3074

1792

if(quit_now){

3075

1793

goto end;

3076

1794

}

3077

1795

3078

if(not init_gpgme(pubkey, seckey, tempdir, &mc)){

3079

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

1796

if(not init_gpgme(pubkey, seckey, tempdir)){

1797

fprintf(stderr, "init_gpgme failed\n");

3080

1798

exitcode = EX_UNAVAILABLE;

3081

1799

goto end;

3082

1800

} else {

3091

1809

/* Connect directly, do not use Zeroconf */

3092

1810

/* (Mainly meant for debugging) */

3093

1811

char *address = strrchr(connect_to, ':');

3094

3095

1812

if(address == NULL){

3096

fprintf_plus(stderr, "No colon in address\n");

1813

fprintf(stderr, "No colon in address\n");

3097

1814

exitcode = EX_USAGE;

3098

1815

goto end;

3099

1816

}

3102

1819

goto end;

3103

1820

}

3104

1821

3105

in_port_t port;

1822

uint16_t port;

3106

1823

errno = 0;

3107

1824

tmpmax = strtoimax(address+1, &tmp, 10);

3108

1825

if(errno != 0 or tmp == address+1 or *tmp != '\0'

3109

or tmpmax != (in_port_t)tmpmax){

3110

fprintf_plus(stderr, "Bad port number\n");

1826

or tmpmax != (uint16_t)tmpmax){

1827

fprintf(stderr, "Bad port number\n");

3111

1828

exitcode = EX_USAGE;

3112

1829

goto end;

3113

1830

}

3114

1831

3115

1832

if(quit_now){

3116

1833

goto end;

3117

1834

}

3118

1835

3119

port = (in_port_t)tmpmax;

1836

port = (uint16_t)tmpmax;

3120

1837

*address = '\0';

3121

1838

/* Colon in address indicates IPv6 */

3122

1839

int af;

3138

1855

}

3139

1856

3140

1857

while(not quit_now){

3141

ret = start_mandos_communication(address, port, if_index, af,

3142

&mc);

1858

ret = start_mandos_communication(address, port, if_index, af);

3143

1859

if(quit_now or ret == 0){

3144

1860

break;

3145

1861

}

3146

1862

if(debug){

3147

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

3148

(int)retry_interval);

1863

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

1864

(int)retry_interval);

3149

1865

}

3150

sleep((unsigned int)retry_interval);

1866

sleep((int)retry_interval);

3151

1867

}

3152

1868

3153

if(not quit_now){

1869

if (not quit_now){

3154

1870

exitcode = EXIT_SUCCESS;

3155

1871

}

3156

1872

3157

1873

goto end;

3158

1874

}

3159

1875

3171

1887

config.publish_domain = 0;

3172

1888

3173

1889

/* Allocate a new server */

3174

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3175

&config, NULL, NULL, &ret);

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

3176

1893

3177

1894

/* Free the Avahi configuration data */

3178

1895

avahi_server_config_free(&config);

3180

1897

3181

1898

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

3182

1899

if(mc.server == NULL){

3183

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

3184

avahi_strerror(ret));

1900

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

1901

avahi_strerror(error));

3185

1902

exitcode = EX_UNAVAILABLE;

3186

1903

goto end;

3187

1904

}

3193

1910

/* Create the Avahi service browser */

3194

1911

sb = avahi_s_service_browser_new(mc.server, if_index,

3195

1912

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3196

NULL, 0, browse_callback,

3197

(void *)&mc);

1913

NULL, 0, browse_callback, NULL);

3198

1914

if(sb == NULL){

3199

fprintf_plus(stderr, "Failed to create service browser: %s\n",

3200

avahi_strerror(avahi_server_errno(mc.server)));

1915

fprintf(stderr, "Failed to create service browser: %s\n",

1916

avahi_strerror(avahi_server_errno(mc.server)));

3201

1917

exitcode = EX_UNAVAILABLE;

3202

1918

goto end;

3203

1919

}

3209

1925

/* Run the main loop */

3210

1926

3211

1927

if(debug){

3212

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

1928

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

3213

1929

}

3214

3215

ret = avahi_loop_with_timeout(simple_poll,

3216

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

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

3217

1933

if(debug){

3218

fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",

3219

(ret == 0) ? "successfully" : "with error");

1934

fprintf(stderr, "avahi_loop_with_timeout exited %s\n",

1935

(ret == 0) ? "successfully" : "with error");

3220

1936

}

3221

1937

3222

1938

end:

3223

1939

3224

1940

if(debug){

3225

if(signal_received){

3226

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

3227

argv[0], signal_received,

3228

strsignal(signal_received));

3229

} else {

3230

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

3231

}

1941

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

3232

1942

}

3233

1943

3234

1944

/* Cleanup things */

3235

free(mc.interfaces);

3236

3237

1945

if(sb != NULL)

3238

1946

avahi_s_service_browser_free(sb);

3239

1947

3240

1948

if(mc.server != NULL)

3241

1949

avahi_server_free(mc.server);

3242

1950

3243

if(simple_poll != NULL)

3244

avahi_simple_poll_free(simple_poll);

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

3245

1953

3246

1954

if(gnutls_initialized){

3247

1955

gnutls_certificate_free_credentials(mc.cred);

1956

gnutls_global_deinit();

3248

1957

gnutls_dh_params_deinit(mc.dh_params);

3249

1958

}

3250

1959

3251

1960

if(gpgme_initialized){

3252

1961

gpgme_release(mc.ctx);

3253

1962

}

3254

1963

3255

1964

/* Cleans up the circular linked list of Mandos servers the client

3256

1965

has seen */

3257

1966

if(mc.current_server != NULL){

3258

1967

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

3259

1968

while(mc.current_server != NULL){

3260

1969

server *next = mc.current_server->next;

3261

#ifdef __GNUC__

3262

#pragma GCC diagnostic push

3263

#pragma GCC diagnostic ignored "-Wcast-qual"

3264

#endif

3265

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

3266

#ifdef __GNUC__

3267

#pragma GCC diagnostic pop

3268

#endif

3269

1970

free(mc.current_server);

3270

1971

mc.current_server = next;

3271

1972

}

3272

1973

}

3273

1974

3274

/* Re-raise privileges */

3275

{

3276

ret = raise_privileges();

3277

if(ret != 0){

3278

errno = ret;

3279

perror_plus("Failed to raise privileges");

3280

} else {

3281

3282

/* Run network hooks */

3283

run_network_hooks("stop", interfaces_hooks != NULL ?

3284

interfaces_hooks : "", delay);

3285

3286

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

3287

{

3288

char *interface = NULL;

3289

while((interface = argz_next(interfaces_to_take_down,

3290

interfaces_to_take_down_size,

3291

interface))){

3292

ret = take_down_interface(interface);

3293

if(ret != 0){

3294

errno = ret;

3295

perror_plus("Failed to take down interface");

3296

}

3297

}

3298

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

3299

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

3300

" down\n");

3301

}

3302

}

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

3303

1982

}

3304

3305

ret = lower_privileges_permanently();

3306

if(ret != 0){

3307

errno = ret;

3308

perror_plus("Failed to lower privileges permanently");

1983

if(geteuid() == 0){

1984

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1992

}

1993

}

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

3309

2004

}

3310

2005

}

3311

2006

3312

free(interfaces_to_take_down);

3313

free(interfaces_hooks);

3314

3315

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

3316

uintmax_t level){

2007

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

2008

if(tempdir_created){

3317

2009

struct dirent **direntries = NULL;

3318

int dret;

3319

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

3320

O_RDONLY

3321

| O_NOFOLLOW

3322

| O_DIRECTORY

3323

| O_PATH));

3324

if(dir_fd == -1){

3325

perror_plus("open");

3326

return;

3327

}

3328

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

3329

notdotentries, alphasort);

3330

if(numentries >= 0){

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

3331

2014

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

3332

if(debug){

3333

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

3334

dirname, direntries[i]->d_name);

3335

}

3336

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

3337

if(dret == -1){

3338

if(errno == EISDIR){

3339

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

3340

AT_REMOVEDIR);

3341

}

3342

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

3343

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

3344

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

3345

/* Recurse only in this special case */

3346

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

3347

dret = 0;

3348

}

3349

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

3350

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

3351

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

3352

}

3353

}

3354

free(direntries[i]);

3355

}

3356

3357

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

3358

free(direntries);

3359

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3360

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

3361

perror_plus("rmdir");

3362

}

3363

} else {

3364

perror_plus("scandirat");

3365

}

3366

close(dir_fd);

3367

}

3368

3369

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

3370

if(tempdir != NULL){

3371

clean_dir_at(-1, tempdir, 0);

2015

direntry = direntries[i];

2016

char *fullname = NULL;

2017

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

2018

direntry->d_name);

2019

if(ret < 0){

2020

perror_plus("asprintf");

2021

continue;

2022

}

2023

ret = remove(fullname);

2024

if(ret == -1){

2025

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

2026

strerror(errno));

2027

}

2028

free(fullname);

2029

}

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

2036

}

2037

ret = rmdir(tempdir);

2038

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

2039

perror_plus("rmdir");

2040

}

3372

2041

}

3373

2042

3374

2043

if(quit_now){