/mandos/trunk : revision 237.4.98

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

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*

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* Everything else is

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*

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* This program is free software: you can redistribute it and/or

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* modify it under the terms of the GNU General Public License as

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

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

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*

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

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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25

* General Public License for more details.

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26

*

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

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* along with this program. If not, see

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

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

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*

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

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31

*/

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33

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

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34

#ifndef _LARGEFILE_SOURCE

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35

#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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37

#ifndef _FILE_OFFSET_BITS

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38

#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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40

41

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

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42

43

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

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stdout, ferror(), remove() */

44

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

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stdout, ferror() */

45

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

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46

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

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47

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

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strtof(), abort() */

48

49

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

49

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

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

50

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

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asprintf(), strncpy(), strsignal()

52

*/

51

53

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

52

54

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

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55

sockaddr_in6, PF_INET6,

55

57

opendir(), DIR */

56

58

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

57

59

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

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inet_pton(), connect() */

59

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

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

60

63

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

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64

*/

62

65

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

63

66

strtoimax() */

64

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

65

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

67

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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72

program_invocation_short_name */

67

73

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

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74

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

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79

*/

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80

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

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81

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

76

setgid(), pause() */

77

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

82

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

83

unlinkat() */

84

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

78

85

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

79

86

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

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87

argp_state, struct argp,

87

94

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

95

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

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96

WEXITSTATUS(), WTERMSIG() */

97

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

98

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

99

argz_delete(), argz_append(),

100

argz_stringify(), argz_add(),

101

argz_count() */

102

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

103

EAI_SYSTEM, gai_strerror() */

90

104

91

105

#ifdef __linux__

92

106

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

134

148

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

135

149

char *connect_to = NULL;

136

150

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

152

uid_t uid = 65534;

153

gid_t gid = 65534;

137

154

138

155

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

139

156

typedef struct server{

140

157

const char *ip;

141

uint16_t port;

158

in_port_t port;

142

159

AvahiIfIndex if_index;

143

160

int af;

144

161

struct timespec last_seen;

148

165

149

166

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

150

167

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

168

AvahiServer *server;

153

169

gnutls_certificate_credentials_t cred;

154

170

unsigned int dh_bits;

156

172

const char *priority;

157

173

gpgme_ctx_t ctx;

158

174

server *current_server;

175

char *interfaces;

176

size_t interfaces_size;

159

177

} mandos_context;

160

178

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

179

/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

166

181

167

182

sig_atomic_t quit_now = 0;

168

183

int signal_received = 0;

169

184

170

185

/* Function to use when printing errors */

171

186

void perror_plus(const char *print_text){

187

int e = errno;

172

188

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

173

189

program_invocation_short_name);

190

errno = e;

174

191

perror(print_text);

175

192

}

176

193

194

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

177

195

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

178

196

va_list ap;

179

197

va_start (ap, format);

180

198

181

199

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

182

200

program_invocation_short_name));

183

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

201

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

184

202

}

185

203

186

204

/*

188

206

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

189

207

* "buffer_length" is how much is already used.

190

208

*/

209

__attribute__((nonnull, warn_unused_result))

191

210

size_t incbuffer(char **buffer, size_t buffer_length,

192

211

size_t buffer_capacity){

193

212

if(buffer_length + BUFFER_SIZE > buffer_capacity){

194

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

195

if(buffer == NULL){

213

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

214

if(new_buf == NULL){

215

int old_errno = errno;

216

free(*buffer);

217

errno = old_errno;

218

*buffer = NULL;

196

219

return 0;

197

220

}

221

*buffer = new_buf;

198

222

buffer_capacity += BUFFER_SIZE;

199

223

}

200

224

return buffer_capacity;

201

225

}

202

226

203

227

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

204

int add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,

205

int af){

228

__attribute__((nonnull, warn_unused_result))

229

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

230

int af, server **current_server){

206

231

int ret;

207

232

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

208

233

if(new_server == NULL){

209

234

perror_plus("malloc");

210

return -1;

235

return false;

211

236

}

212

237

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

213

238

.port = port,

215

240

.af = af };

216

241

if(new_server->ip == NULL){

217

242

perror_plus("strdup");

218

return -1;

243

free(new_server);

244

return false;

245

}

246

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

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

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

return false;

219

259

}

220

260

/* Special case of first server */

221

if (mc.current_server == NULL){

261

if(*current_server == NULL){

222

262

new_server->next = new_server;

223

263

new_server->prev = new_server;

224

mc.current_server = new_server;

225

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

264

*current_server = new_server;

226

265

} else {

227

new_server->next = mc.current_server;

228

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

266

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

267

new_server->next = *current_server;

268

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

229

269

new_server->prev->next = new_server;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

270

(*current_server)->prev = new_server;

271

}

272

return true;

238

273

}

239

274

240

275

/*

241

276

* Initialize GPGME.

242

277

*/

243

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

244

const char *tempdir){

278

__attribute__((nonnull, warn_unused_result))

279

static bool init_gpgme(const char * const seckey,

280

const char * const pubkey,

281

const char * const tempdir,

282

mandos_context *mc){

245

283

gpgme_error_t rc;

246

284

gpgme_engine_info_t engine_info;

247

285

248

249

286

/*

250

287

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

251

288

*/

252

bool import_key(const char *filename){

289

bool import_key(const char * const filename){

253

290

int ret;

254

291

int fd;

255

292

gpgme_data_t pgp_data;

267

304

return false;

268

305

}

269

306

270

rc = gpgme_op_import(mc.ctx, pgp_data);

307

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

271

308

if(rc != GPG_ERR_NO_ERROR){

272

309

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

273

310

gpgme_strsource(rc), gpgme_strerror(rc));

274

311

return false;

275

312

}

276

313

277

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

314

ret = close(fd);

278

315

if(ret == -1){

279

316

perror_plus("close");

280

317

}

317

354

}

318

355

319

356

/* Create new GPGME "context" */

320

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

357

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

321

358

if(rc != GPG_ERR_NO_ERROR){

322

359

fprintf_plus(stderr, "Mandos plugin mandos-client: "

323

360

"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),

336

373

* Decrypt OpenPGP data.

337

374

* Returns -1 on error

338

375

*/

376

__attribute__((nonnull, warn_unused_result))

339

377

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

378

size_t crypto_size,

341

char **plaintext){

379

char **plaintext,

380

mandos_context *mc){

342

381

gpgme_data_t dh_crypto, dh_plain;

343

382

gpgme_error_t rc;

344

383

ssize_t ret;

370

409

371

410

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

372

411

data buffer */

373

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

412

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

374

413

if(rc != GPG_ERR_NO_ERROR){

375

414

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

376

415

gpgme_strsource(rc), gpgme_strerror(rc));

377

416

plaintext_length = -1;

378

417

if(debug){

379

418

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

419

result = gpgme_op_decrypt_result(mc->ctx);

381

420

if(result == NULL){

382

421

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

383

422

} else {

460

499

return plaintext_length;

461

500

}

462

501

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

466

if(ret == NULL)

467

ret = "(unknown)";

468

return ret;

502

__attribute__((warn_unused_result, const))

503

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

504

if(str == NULL)

505

return "(unknown)";

506

return str;

507

}

508

509

__attribute__((warn_unused_result))

510

static const char *safer_gnutls_strerror(int value){

511

const char *ret = gnutls_strerror(value);

512

return safe_string(ret);

469

513

}

470

514

471

515

/* GnuTLS log function callback */

516

__attribute__((nonnull))

472

517

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

473

518

const char* string){

474

519

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

475

520

}

476

521

522

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

477

523

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

526

mandos_context *mc){

479

527

int ret;

528

unsigned int uret;

480

529

481

530

if(debug){

482

531

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

483

532

}

484

533

485

ret = gnutls_global_init();

486

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

489

return -1;

490

}

491

492

534

if(debug){

493

535

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

494

536

* - GnuTLS manual

498

540

}

499

541

500

542

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

544

if(ret != GNUTLS_E_SUCCESS){

503

545

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

504

546

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

506

547

return -1;

507

548

}

508

549

514

555

}

515

556

516

557

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

558

(mc->cred, pubkeyfilename, seckeyfilename,

518

559

GNUTLS_OPENPGP_FMT_BASE64);

519

560

if(ret != GNUTLS_E_SUCCESS){

520

561

fprintf_plus(stderr,

526

567

}

527

568

528

569

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

570

ret = gnutls_dh_params_init(&mc->dh_params);

530

571

if(ret != GNUTLS_E_SUCCESS){

531

572

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

573

" initialization: %s\n",

533

574

safer_gnutls_strerror(ret));

534

575

goto globalfail;

535

576

}

536

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

537

if(ret != GNUTLS_E_SUCCESS){

538

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

539

safer_gnutls_strerror(ret));

540

goto globalfail;

541

}

542

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

577

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

578

if(dhparamsfilename != NULL){

579

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

580

do {

581

int dhpfile = open(dhparamsfilename, O_RDONLY);

582

if(dhpfile == -1){

583

perror_plus("open");

584

dhparamsfilename = NULL;

585

break;

586

}

587

size_t params_capacity = 0;

588

while(true){

589

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

590

(size_t)params.size,

591

(size_t)params_capacity);

592

if(params_capacity == 0){

593

perror_plus("incbuffer");

594

free(params.data);

595

params.data = NULL;

596

dhparamsfilename = NULL;

597

break;

598

}

599

ssize_t bytes_read = read(dhpfile,

600

params.data + params.size,

601

BUFFER_SIZE);

602

/* EOF */

603

if(bytes_read == 0){

604

break;

605

}

606

/* check bytes_read for failure */

607

if(bytes_read < 0){

608

perror_plus("read");

609

free(params.data);

610

params.data = NULL;

611

dhparamsfilename = NULL;

612

break;

613

}

614

params.size += (unsigned int)bytes_read;

615

}

616

ret = close(dhpfile);

617

if(ret == -1){

618

perror_plus("close");

619

}

620

if(params.data == NULL){

621

dhparamsfilename = NULL;

622

}

623

if(dhparamsfilename == NULL){

624

break;

625

}

626

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

627

GNUTLS_X509_FMT_PEM);

628

if(ret != GNUTLS_E_SUCCESS){

629

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

630

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

631

safer_gnutls_strerror(ret));

632

dhparamsfilename = NULL;

633

}

634

free(params.data);

635

} while(false);

636

}

637

if(dhparamsfilename == NULL){

638

if(mc->dh_bits == 0){

639

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

640

/* Try to read the private key file */

641

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

642

do {

643

int secfile = open(seckeyfilename, O_RDONLY);

644

if(secfile == -1){

645

perror_plus("open");

646

break;

647

}

648

size_t buffer_capacity = 0;

649

while(true){

650

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

651

(size_t)buffer.size,

652

(size_t)buffer_capacity);

653

if(buffer_capacity == 0){

654

perror_plus("incbuffer");

655

free(buffer.data);

656

buffer.data = NULL;

657

break;

658

}

659

ssize_t bytes_read = read(secfile,

660

buffer.data + buffer.size,

661

BUFFER_SIZE);

662

/* EOF */

663

if(bytes_read == 0){

664

break;

665

}

666

/* check bytes_read for failure */

667

if(bytes_read < 0){

668

perror_plus("read");

669

free(buffer.data);

670

buffer.data = NULL;

671

break;

672

}

673

buffer.size += (unsigned int)bytes_read;

674

}

675

close(secfile);

676

} while(false);

677

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

678

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

679

if(buffer.data != NULL){

680

{

681

gnutls_openpgp_privkey_t privkey = NULL;

682

ret = gnutls_openpgp_privkey_init(&privkey);

683

if(ret != GNUTLS_E_SUCCESS){

684

fprintf_plus(stderr, "Error initializing OpenPGP key"

685

" structure: %s",

686

safer_gnutls_strerror(ret));

687

free(buffer.data);

688

buffer.data = NULL;

689

} else {

690

ret = gnutls_openpgp_privkey_import

691

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

692

if(ret != GNUTLS_E_SUCCESS){

693

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

694

safer_gnutls_strerror(ret));

695

privkey = NULL;

696

}

697

free(buffer.data);

698

buffer.data = NULL;

699

if(privkey != NULL){

700

/* Use private key to suggest an appropriate

701

sec_param */

702

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

703

gnutls_openpgp_privkey_deinit(privkey);

704

if(debug){

705

fprintf_plus(stderr, "This OpenPGP key implies using"

706

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

707

safe_string(gnutls_sec_param_get_name

708

(sec_param)));

709

}

710

}

711

}

712

}

713

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

714

/* Err on the side of caution */

715

sec_param = GNUTLS_SEC_PARAM_ULTRA;

716

if(debug){

717

fprintf_plus(stderr, "Falling back to security parameter"

718

" \"%s\"\n",

719

safe_string(gnutls_sec_param_get_name

720

(sec_param)));

721

}

722

}

723

}

724

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

725

if(uret != 0){

726

mc->dh_bits = uret;

727

if(debug){

728

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

729

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

730

safe_string(gnutls_sec_param_get_name

731

(sec_param)),

732

mc->dh_bits);

733

}

734

} else {

735

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

736

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

737

safe_string(gnutls_sec_param_get_name

738

(sec_param)),

739

safer_gnutls_strerror(ret));

740

goto globalfail;

741

}

742

} else if(debug){

743

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

744

mc->dh_bits);

745

}

746

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

747

if(ret != GNUTLS_E_SUCCESS){

748

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

749

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

750

safer_gnutls_strerror(ret));

751

goto globalfail;

752

}

753

}

754

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

544

755

545

756

return 0;

546

757

547

758

globalfail:

548

759

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

760

gnutls_certificate_free_credentials(mc->cred);

761

gnutls_dh_params_deinit(mc->dh_params);

552

762

return -1;

553

763

}

554

764

555

static int init_gnutls_session(gnutls_session_t *session){

765

__attribute__((nonnull, warn_unused_result))

766

static int init_gnutls_session(gnutls_session_t *session,

767

mandos_context *mc){

556

768

int ret;

557

769

/* GnuTLS session creation */

558

770

do {

570

782

{

571

783

const char *err;

572

784

do {

573

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

785

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

574

786

if(quit_now){

575

787

gnutls_deinit(*session);

576

788

return -1;

587

799

588

800

do {

589

801

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

802

mc->cred);

591

803

if(quit_now){

592

804

gnutls_deinit(*session);

593

805

return -1;

603

815

/* ignore client certificate if any. */

604

816

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

817

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

818

return 0;

609

819

}

610

820

612

822

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

613

823

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

614

824

825

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

826

__attribute__((warn_unused_result))

827

int raise_privileges(void){

828

int old_errno = errno;

829

int ret = 0;

830

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

831

ret = errno;

832

}

833

errno = old_errno;

834

return ret;

835

}

836

837

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

838

__attribute__((warn_unused_result))

839

int raise_privileges_permanently(void){

840

int old_errno = errno;

841

int ret = raise_privileges();

842

if(ret != 0){

843

errno = old_errno;

844

return ret;

845

}

846

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

847

ret = errno;

848

}

849

errno = old_errno;

850

return ret;

851

}

852

853

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

854

__attribute__((warn_unused_result))

855

int lower_privileges(void){

856

int old_errno = errno;

857

int ret = 0;

858

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

859

ret = errno;

860

}

861

errno = old_errno;

862

return ret;

863

}

864

865

/* Lower privileges permanently */

866

__attribute__((warn_unused_result))

867

int lower_privileges_permanently(void){

868

int old_errno = errno;

869

int ret = 0;

870

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

871

ret = errno;

872

}

873

errno = old_errno;

874

return ret;

875

}

876

877

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

878

__attribute__((nonnull, warn_unused_result))

879

static bool add_delete_local_route(const bool add,

880

const char *address,

881

AvahiIfIndex if_index){

882

int ret;

883

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

884

char add_arg[] = "add";

885

char delete_arg[] = "delete";

886

char debug_flag[] = "--debug";

887

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

888

if(pluginhelperdir == NULL){

889

if(debug){

890

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

891

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

892

}

893

return false;

894

}

895

896

char interface[IF_NAMESIZE];

897

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

898

perror_plus("if_indextoname");

899

return false;

900

}

901

902

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

903

if(devnull == -1){

904

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

905

return false;

906

}

907

pid_t pid = fork();

908

if(pid == 0){

909

/* Child */

910

/* Raise privileges */

911

errno = raise_privileges_permanently();

912

if(errno != 0){

913

perror_plus("Failed to raise privileges");

914

/* _exit(EX_NOPERM); */

915

} else {

916

/* Set group */

917

errno = 0;

918

ret = setgid(0);

919

if(ret == -1){

920

perror_plus("setgid");

921

_exit(EX_NOPERM);

922

}

923

/* Reset supplementary groups */

924

errno = 0;

925

ret = setgroups(0, NULL);

926

if(ret == -1){

927

perror_plus("setgroups");

928

_exit(EX_NOPERM);

929

}

930

}

931

ret = dup2(devnull, STDIN_FILENO);

932

if(ret == -1){

933

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

934

_exit(EX_OSERR);

935

}

936

ret = close(devnull);

937

if(ret == -1){

938

perror_plus("close");

939

_exit(EX_OSERR);

940

}

941

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

942

if(ret == -1){

943

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

944

_exit(EX_OSERR);

945

}

946

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

947

O_RDONLY

948

| O_DIRECTORY

949

| O_PATH

950

| O_CLOEXEC));

951

if(helperdir_fd == -1){

952

perror_plus("open");

953

_exit(EX_UNAVAILABLE);

954

}

955

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

956

helper, O_RDONLY));

957

if(helper_fd == -1){

958

perror_plus("openat");

959

close(helperdir_fd);

960

_exit(EX_UNAVAILABLE);

961

}

962

close(helperdir_fd);

963

#ifdef __GNUC__

964

#pragma GCC diagnostic push

965

#pragma GCC diagnostic ignored "-Wcast-qual"

966

#endif

967

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

968

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

969

interface, debug ? debug_flag : NULL, NULL },

970

environ) == -1){

971

#ifdef __GNUC__

972

#pragma GCC diagnostic pop

973

#endif

974

perror_plus("fexecve");

975

_exit(EXIT_FAILURE);

976

}

977

}

978

if(pid == -1){

979

perror_plus("fork");

980

return false;

981

}

982

int status;

983

pid_t pret = -1;

984

errno = 0;

985

do {

986

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

987

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

988

int errno_raising = 0;

989

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

990

errno_raising = errno;

991

perror_plus("Failed to raise privileges in order to"

992

" kill helper program");

993

}

994

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

995

perror_plus("kill");

996

}

997

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

998

perror_plus("Failed to lower privileges after killing"

999

" helper program");

1000

}

1001

return false;

1002

}

1003

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

1004

if(pret == -1){

1005

perror_plus("waitpid");

1006

return false;

1007

}

1008

if(WIFEXITED(status)){

1009

if(WEXITSTATUS(status) != 0){

1010

fprintf_plus(stderr, "Error: iprouteadddel exited"

1011

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

1012

return false;

1013

}

1014

return true;

1015

}

1016

if(WIFSIGNALED(status)){

1017

fprintf_plus(stderr, "Error: iprouteadddel died by"

1018

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

1019

return false;

1020

}

1021

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

1022

return false;

1023

}

1024

1025

__attribute__((nonnull, warn_unused_result))

1026

static bool add_local_route(const char *address,

1027

AvahiIfIndex if_index){

1028

if(debug){

1029

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

1030

}

1031

return add_delete_local_route(true, address, if_index);

1032

}

1033

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool delete_local_route(const char *address,

1036

AvahiIfIndex if_index){

1037

if(debug){

1038

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

1039

}

1040

return add_delete_local_route(false, address, if_index);

1041

}

1042

615

1043

/* Called when a Mandos server is found */

616

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

1044

__attribute__((nonnull, warn_unused_result))

1045

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

617

1046

AvahiIfIndex if_index,

618

int af){

1047

int af, mandos_context *mc){

619

1048

int ret, tcp_sd = -1;

620

1049

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1050

struct sockaddr_storage to;

625

1051

char *buffer = NULL;

626

1052

char *decrypted_buffer = NULL;

627

1053

size_t buffer_length = 0;

630

1056

int retval = -1;

631

1057

gnutls_session_t session;

632

1058

int pf; /* Protocol family */

1059

bool route_added = false;

633

1060

634

1061

errno = 0;

635

1062

651

1078

return -1;

652

1079

}

653

1080

654

ret = init_gnutls_session(&session);

1081

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

1082

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

1083

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

1084

bool match = false;

1085

{

1086

char *interface = NULL;

1087

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

1088

mc->interfaces_size,

1089

interface))){

1090

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

1091

match = true;

1092

break;

1093

}

1094

}

1095

}

1096

if(not match){

1097

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

1098

connect to the server */

1099

if(debug){

1100

char interface[IF_NAMESIZE];

1101

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

1102

perror_plus("if_indextoname");

1103

} else {

1104

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

1105

" \"%s\"\n",

1106

if_indextoname((unsigned int)if_index,

1107

interface));

1108

}

1109

}

1110

return -1;

1111

}

1112

}

1113

1114

ret = init_gnutls_session(&session, mc);

655

1115

if(ret != 0){

656

1116

return -1;

657

1117

}

658

1118

659

1119

if(debug){

660

1120

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

661

PRIu16 "\n", ip, port);

1121

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

662

1122

}

663

1123

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1124

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

665

1125

if(tcp_sd < 0){

666

1126

int e = errno;

667

1127

perror_plus("socket");

674

1134

goto mandos_end;

675

1135

}

676

1136

677

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

678

1137

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1138

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

1139

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

1140

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

681

1141

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

1142

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

1143

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

1144

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

684

1145

}

685

1146

if(ret < 0 ){

686

1147

int e = errno;

695

1156

goto mandos_end;

696

1157

}

697

1158

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

1159

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

1160

if(IN6_IS_ADDR_LINKLOCAL

1161

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

705

1162

if(if_index == AVAHI_IF_UNSPEC){

706

1163

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

707

1164

" incomplete without a network interface\n");

709

1166

goto mandos_end;

710

1167

}

711

1168

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1169

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

713

1170

}

714

1171

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1172

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

718

1173

}

719

1174

720

1175

if(quit_now){

728

1183

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

729

1184

perror_plus("if_indextoname");

730

1185

} else {

731

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16

732

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

1186

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

1187

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

733

1188

}

734

1189

} else {

735

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

736

ip, port);

1190

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

1191

ip, (uintmax_t)port);

737

1192

}

738

1193

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1194

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

741

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

744

} else {

745

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

746

sizeof(addrstr));

747

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

754

}

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

760

}

761

762

if(af == AF_INET6){

763

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

764

} else {

765

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

766

}

767

if(ret < 0){

768

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

769

int e = errno;

770

perror_plus("connect");

771

errno = e;

772

}

773

goto mandos_end;

774

}

775

776

if(quit_now){

777

errno = EINTR;

778

goto mandos_end;

1195

if(af == AF_INET6){

1196

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

1197

sizeof(struct sockaddr_in6),

1198

addrstr, sizeof(addrstr), NULL, 0,

1199

NI_NUMERICHOST);

1200

} else {

1201

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

1202

sizeof(struct sockaddr_in),

1203

addrstr, sizeof(addrstr), NULL, 0,

1204

NI_NUMERICHOST);

1205

}

1206

if(ret == EAI_SYSTEM){

1207

perror_plus("getnameinfo");

1208

} else if(ret != 0) {

1209

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

1210

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

1211

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

1212

}

1213

}

1214

1215

if(quit_now){

1216

errno = EINTR;

1217

goto mandos_end;

1218

}

1219

1220

while(true){

1221

if(af == AF_INET6){

1222

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

1223

sizeof(struct sockaddr_in6));

1224

} else {

1225

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

1226

sizeof(struct sockaddr_in));

1227

}

1228

if(ret < 0){

1229

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

1230

and if_index != AVAHI_IF_UNSPEC

1231

and connect_to == NULL

1232

and not route_added and

1233

((af == AF_INET6 and not

1234

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1235

&to)->sin6_addr)))

1236

or (af == AF_INET and

1237

/* Not a a IPv4LL address */

1238

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

1239

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

1240

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

1241

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

1242

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

1243

connect to a Mandos server announced by Avahi on a server

1244

host with a global address. Work around this by retrying

1245

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

1246

1247

Avahi bug reference:

1248

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

1249

https://bugs.debian.org/587961

1250

*/

1251

if(debug){

1252

fprintf_plus(stderr, "Mandos server unreachable, trying"

1253

" direct route\n");

1254

}

1255

int e = errno;

1256

route_added = add_local_route(ip, if_index);

1257

if(route_added){

1258

continue;

1259

}

1260

errno = e;

1261

}

1262

if(errno != ECONNREFUSED or debug){

1263

int e = errno;

1264

perror_plus("connect");

1265

errno = e;

1266

}

1267

goto mandos_end;

1268

}

1269

1270

if(quit_now){

1271

errno = EINTR;

1272

goto mandos_end;

1273

}

1274

break;

779

1275

}

780

1276

781

1277

const char *out = mandos_protocol_version;

817

1313

goto mandos_end;

818

1314

}

819

1315

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1316

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

1317

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

1318

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

1319

gnutls_transport_set_ptr(session,

1320

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

1321

823

1322

if(quit_now){

824

1323

errno = EINTR;

929

1428

if(buffer_length > 0){

930

1429

ssize_t decrypted_buffer_size;

931

1430

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1431

&decrypted_buffer, mc);

933

1432

if(decrypted_buffer_size >= 0){

934

1433

1434

clearerr(stdout);

935

1435

written = 0;

936

1436

while(written < (size_t) decrypted_buffer_size){

937

1437

if(quit_now){

953

1453

}

954

1454

written += (size_t)ret;

955

1455

}

1456

ret = fflush(stdout);

1457

if(ret != 0){

1458

int e = errno;

1459

if(debug){

1460

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

1461

strerror(errno));

1462

}

1463

errno = e;

1464

goto mandos_end;

1465

}

956

1466

retval = 0;

957

1467

}

958

1468

}

961

1471

962

1472

mandos_end:

963

1473

{

1474

if(route_added){

1475

if(not delete_local_route(ip, if_index)){

1476

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

1477

" interface %d", ip, if_index);

1478

}

1479

}

964

1480

int e = errno;

965

1481

free(decrypted_buffer);

966

1482

free(buffer);

967

1483

if(tcp_sd >= 0){

968

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

1484

ret = close(tcp_sd);

969

1485

}

970

1486

if(ret == -1){

971

1487

if(e == 0){

996

1512

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1513

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1514

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1515

void *mc){

1516

if(r == NULL){

1517

return;

1518

}

1001

1519

1002

1520

/* Called whenever a service has been resolved successfully or

1003

1521

timed out */

1004

1522

1005

1523

if(quit_now){

1524

avahi_s_service_resolver_free(r);

1006

1525

return;

1007

1526

}

1008

1527

1012

1531

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

1013

1532

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

1014

1533

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1534

avahi_strerror(avahi_server_errno

1535

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

1016

1536

break;

1017

1537

1018

1538

case AVAHI_RESOLVER_FOUND:

1024

1544

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

1025

1545

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

1026

1546

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1547

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

1548

interface,

1549

avahi_proto_to_af(proto),

1550

mc);

1029

1551

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1552

avahi_simple_poll_quit(simple_poll);

1031

1553

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1554

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

1555

avahi_proto_to_af(proto),

1556

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

1557

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

1558

" list\n", name);

1559

}

1034

1560

}

1035

1561

}

1036

1562

}

1046

1572

const char *domain,

1047

1573

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1574

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1575

void *mc){

1576

if(b == NULL){

1577

return;

1578

}

1051

1579

1052

1580

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

1053

1581

is removed from the LAN */

1061

1589

case AVAHI_BROWSER_FAILURE:

1062

1590

1063

1591

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1592

avahi_strerror(avahi_server_errno

1593

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

1594

avahi_simple_poll_quit(simple_poll);

1066

1595

return;

1067

1596

1068

1597

case AVAHI_BROWSER_NEW:

1071

1600

the callback function is called the Avahi server will free the

1072

1601

resolver for us. */

1073

1602

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1603

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

1604

interface, protocol, name, type,

1605

domain, protocol, 0,

1606

resolve_callback, mc) == NULL)

1077

1607

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

1078

1608

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1609

avahi_strerror(avahi_server_errno

1610

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

1080

1611

break;

1081

1612

1082

1613

case AVAHI_BROWSER_REMOVE:

1101

1632

signal_received = sig;

1102

1633

int old_errno = errno;

1103

1634

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1635

if(simple_poll != NULL){

1636

avahi_simple_poll_quit(simple_poll);

1106

1637

}

1107

1638

errno = old_errno;

1108

1639

}

1109

1640

1641

__attribute__((nonnull, warn_unused_result))

1110

1642

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

1111

1643

int ret;

1644

int old_errno;

1112

1645

1113

1646

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

1114

1647

if(s < 0){

1648

old_errno = errno;

1115

1649

perror_plus("socket");

1650

errno = old_errno;

1116

1651

return false;

1117

1652

}

1118

strcpy(ifr->ifr_name, ifname);

1653

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

1654

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

1119

1655

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1656

if(ret == -1){

1121

1657

if(debug){

1658

old_errno = errno;

1122

1659

perror_plus("ioctl SIOCGIFFLAGS");

1660

errno = old_errno;

1661

}

1662

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

1663

old_errno = errno;

1664

perror_plus("close");

1665

errno = old_errno;

1123

1666

}

1124

1667

return false;

1125

1668

}

1669

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

1670

old_errno = errno;

1671

perror_plus("close");

1672

errno = old_errno;

1673

}

1126

1674

return true;

1127

1675

}

1128

1676

1677

__attribute__((nonnull, warn_unused_result))

1129

1678

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

1130

1679

1131

1680

/* Reject the loopback device */

1173

1722

* corresponds to an acceptable network device.

1174

1723

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

1175

1724

*/

1725

__attribute__((nonnull, warn_unused_result))

1176

1726

int good_interface(const struct dirent *if_entry){

1177

1727

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

1178

1728

return 0;

1194

1744

}

1195

1745

1196

1746

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

if(not (ifr.ifr_flags & IFF_UP)){

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

if(not (ifr.ifr_flags & IFF_RUNNING)){

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1747

* This function determines if a network interface is up.

1748

*/

1749

__attribute__((nonnull, warn_unused_result))

1750

bool interface_is_up(const char *interface){

1751

struct ifreq ifr;

1752

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

1753

if(debug){

1754

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

1755

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

1756

}

1757

return false;

1758

}

1759

1760

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

1761

}

1762

1763

/*

1764

* This function determines if a network interface is running

1765

*/

1766

__attribute__((nonnull, warn_unused_result))

1767

bool interface_is_running(const char *interface){

1768

struct ifreq ifr;

1769

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

1770

if(debug){

1771

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

1772

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

1773

}

1774

return false;

1775

}

1776

1777

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

1778

}

1779

1780

__attribute__((nonnull, pure, warn_unused_result))

1239

1781

int notdotentries(const struct dirent *direntry){

1240

1782

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

1241

1783

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

1248

1790

}

1249

1791

1250

1792

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

1793

__attribute__((nonnull, warn_unused_result))

1251

1794

int runnable_hook(const struct dirent *direntry){

1252

1795

int ret;

1253

1796

size_t sret;

1261

1804

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

1262

1805

"abcdefghijklmnopqrstuvwxyz"

1263

1806

"0123456789"

1264

"_-");

1807

"_.-");

1265

1808

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

1266

1809

/* Contains non-allowed characters */

1267

1810

if(debug){

1271

1814

return 0;

1272

1815

}

1273

1816

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1817

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

1282

1818

if(ret == -1){

1283

1819

if(debug){

1284

1820

perror_plus("Could not stat hook");

1308

1844

return 1;

1309

1845

}

1310

1846

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1847

__attribute__((nonnull, warn_unused_result))

1848

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1849

mandos_context *mc){

1312

1850

int ret;

1313

1851

struct timespec now;

1314

1852

struct timespec waited_time;

1315

1853

intmax_t block_time;

1316

1854

1317

1855

while(true){

1318

if(mc.current_server == NULL){

1319

if (debug){

1856

if(mc->current_server == NULL){

1857

if(debug){

1320

1858

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

1321

1859

" No timeout!\n");

1322

1860

}

1323

1861

ret = avahi_simple_poll_iterate(s, -1);

1324

1862

} else {

1325

if (debug){

1863

if(debug){

1326

1864

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

1327

1865

" it, or wait\n");

1328

1866

}

1335

1873

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

1336

1874

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

1337

1875

waited_time.tv_sec = (now.tv_sec

1338

- mc.current_server->last_seen.tv_sec);

1876

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

1339

1877

waited_time.tv_nsec = (now.tv_nsec

1340

- mc.current_server->last_seen.tv_nsec);

1878

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

1341

1879

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

1342

1880

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

1343

1881

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

1345

1883

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

1346

1884

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

1347

1885

1348

if (debug){

1886

if(debug){

1349

1887

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

1350

1888

block_time);

1351

1889

}

1352

1890

1353

1891

if(block_time <= 0){

1354

ret = start_mandos_communication(mc.current_server->ip,

1355

mc.current_server->port,

1356

mc.current_server->if_index,

1357

mc.current_server->af);

1892

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

1893

mc->current_server->port,

1894

mc->current_server->if_index,

1895

mc->current_server->af, mc);

1358

1896

if(ret == 0){

1359

avahi_simple_poll_quit(mc.simple_poll);

1897

avahi_simple_poll_quit(s);

1360

1898

return 0;

1361

1899

}

1362

1900

ret = clock_gettime(CLOCK_MONOTONIC,

1363

&mc.current_server->last_seen);

1901

&mc->current_server->last_seen);

1364

1902

if(ret == -1){

1365

1903

perror_plus("clock_gettime");

1366

1904

return -1;

1367

1905

}

1368

mc.current_server = mc.current_server->next;

1906

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

1369

1907

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

1370

1908

servers, but don't block */

1371

1909

}

1373

1911

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

1374

1912

}

1375

1913

if(ret != 0){

1376

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

1914

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

1377

1915

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

1378

1916

}

1379

1917

}

1380

1918

}

1381

1919

}

1382

1920

1383

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

1921

__attribute__((nonnull))

1922

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

1384

1923

const float delay){

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1924

struct dirent **direntries = NULL;

1925

if(hookdir_fd == -1){

1926

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1927

| O_CLOEXEC);

1928

if(hookdir_fd == -1){

1929

if(errno == ENOENT){

1930

if(debug){

1931

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

1932

" found\n", hookdir);

1933

}

1934

} else {

1935

perror_plus("open");

1936

}

1937

return;

1938

}

1939

}

1940

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

1941

if(devnull == -1){

1942

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

1943

return;

1944

}

1945

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

1946

runnable_hook, alphasort);

1390

1947

if(numhooks == -1){

1391

1948

perror_plus("scandir");

1392

} else {

1393

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

1394

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

1395

direntry = direntries[i];

1396

char *fullname = NULL;

1397

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

1398

if(ret < 0){

1949

close(devnull);

1950

return;

1951

}

1952

struct dirent *direntry;

1953

int ret;

1954

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

1955

direntry = direntries[i];

1956

if(debug){

1957

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

1958

direntry->d_name);

1959

}

1960

pid_t hook_pid = fork();

1961

if(hook_pid == 0){

1962

/* Child */

1963

/* Raise privileges */

1964

errno = raise_privileges_permanently();

1965

if(errno != 0){

1966

perror_plus("Failed to raise privileges");

1967

_exit(EX_NOPERM);

1968

}

1969

/* Set group */

1970

errno = 0;

1971

ret = setgid(0);

1972

if(ret == -1){

1973

perror_plus("setgid");

1974

_exit(EX_NOPERM);

1975

}

1976

/* Reset supplementary groups */

1977

errno = 0;

1978

ret = setgroups(0, NULL);

1979

if(ret == -1){

1980

perror_plus("setgroups");

1981

_exit(EX_NOPERM);

1982

}

1983

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

1984

if(ret == -1){

1985

perror_plus("setenv");

1986

_exit(EX_OSERR);

1987

}

1988

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

1989

if(ret == -1){

1990

perror_plus("setenv");

1991

_exit(EX_OSERR);

1992

}

1993

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

1994

if(ret == -1){

1995

perror_plus("setenv");

1996

_exit(EX_OSERR);

1997

}

1998

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

1999

if(ret == -1){

2000

perror_plus("setenv");

2001

_exit(EX_OSERR);

2002

}

2003

char *delaystring;

2004

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

2005

if(ret == -1){

1399

2006

perror_plus("asprintf");

1400

continue;

1401

}

1402

if(debug){

1403

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

1404

direntry->d_name);

1405

}

1406

pid_t hook_pid = fork();

1407

if(hook_pid == 0){

1408

/* Child */

1409

dup2(devnull, STDIN_FILENO);

1410

close(devnull);

1411

dup2(STDERR_FILENO, STDOUT_FILENO);

1412

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

1413

if(ret == -1){

1414

perror_plus("setenv");

1415

return false;

1416

}

1417

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

1418

if(ret == -1){

1419

perror_plus("setenv");

1420

return false;

1421

}

1422

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

1423

if(ret == -1){

1424

perror_plus("setenv");

1425

return false;

1426

}

1427

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

1428

if(ret == -1){

1429

perror_plus("setenv");

1430

return false;

1431

}

1432

char *delaystring;

1433

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

1434

if(ret == -1){

1435

perror_plus("asprintf");

1436

return false;

1437

}

1438

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

1439

if(ret == -1){

1440

free(delaystring);

1441

perror_plus("setenv");

1442

return false;

1443

}

2007

_exit(EX_OSERR);

2008

}

2009

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

2010

if(ret == -1){

1444

2011

free(delaystring);

1445

ret = execl(fullname, direntry->d_name, mode, NULL);

1446

perror_plus("execl");

1447

} else {

1448

int status;

1449

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

1450

perror_plus("waitpid");

1451

free(fullname);

1452

continue;

1453

}

1454

if(WIFEXITED(status)){

1455

if(WEXITSTATUS(status) != 0){

1456

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

1457

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

1458

WEXITSTATUS(status));

1459

free(fullname);

1460

continue;

1461

}

1462

} else if(WIFSIGNALED(status)){

1463

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

1464

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

1465

WTERMSIG(status));

1466

free(fullname);

1467

continue;

1468

} else {

1469

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

1470

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

1471

free(fullname);

1472

continue;

1473

}

1474

}

1475

free(fullname);

1476

if(debug){

1477

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

1478

direntry->d_name);

1479

}

1480

}

1481

close(devnull);

1482

}

1483

return true;

2012

perror_plus("setenv");

2013

_exit(EX_OSERR);

2014

}

2015

free(delaystring);

2016

if(connect_to != NULL){

2017

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

2018

if(ret == -1){

2019

perror_plus("setenv");

2020

_exit(EX_OSERR);

2021

}

2022

}

2023

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

2024

direntry->d_name,

2025

O_RDONLY));

2026

if(hook_fd == -1){

2027

perror_plus("openat");

2028

_exit(EXIT_FAILURE);

2029

}

2030

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

2031

perror_plus("close");

2032

_exit(EXIT_FAILURE);

2033

}

2034

ret = dup2(devnull, STDIN_FILENO);

2035

if(ret == -1){

2036

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

2037

_exit(EX_OSERR);

2038

}

2039

ret = close(devnull);

2040

if(ret == -1){

2041

perror_plus("close");

2042

_exit(EX_OSERR);

2043

}

2044

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2045

if(ret == -1){

2046

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

2047

_exit(EX_OSERR);

2048

}

2049

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

2050

environ) == -1){

2051

perror_plus("fexecve");

2052

_exit(EXIT_FAILURE);

2053

}

2054

} else {

2055

if(hook_pid == -1){

2056

perror_plus("fork");

2057

free(direntry);

2058

continue;

2059

}

2060

int status;

2061

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

2062

perror_plus("waitpid");

2063

free(direntry);

2064

continue;

2065

}

2066

if(WIFEXITED(status)){

2067

if(WEXITSTATUS(status) != 0){

2068

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

2069

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

2070

WEXITSTATUS(status));

2071

free(direntry);

2072

continue;

2073

}

2074

} else if(WIFSIGNALED(status)){

2075

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

2076

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

2077

WTERMSIG(status));

2078

free(direntry);

2079

continue;

2080

} else {

2081

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

2082

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

2083

free(direntry);

2084

continue;

2085

}

2086

}

2087

if(debug){

2088

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

2089

direntry->d_name);

2090

}

2091

free(direntry);

2092

}

2093

free(direntries);

2094

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

2095

perror_plus("close");

2096

} else {

2097

hookdir_fd = -1;

2098

}

2099

close(devnull);

2100

}

2101

2102

__attribute__((nonnull, warn_unused_result))

2103

int bring_up_interface(const char *const interface,

2104

const float delay){

2105

int old_errno = errno;

2106

int ret;

2107

struct ifreq network;

2108

unsigned int if_index = if_nametoindex(interface);

2109

if(if_index == 0){

2110

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

2111

errno = old_errno;

2112

return ENXIO;

2113

}

2114

2115

if(quit_now){

2116

errno = old_errno;

2117

return EINTR;

2118

}

2119

2120

if(not interface_is_up(interface)){

2121

int ret_errno = 0;

2122

int ioctl_errno = 0;

2123

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

2124

ret_errno = errno;

2125

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

2126

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

2127

errno = old_errno;

2128

return ret_errno;

2129

}

2130

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

2131

2132

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

2133

if(sd == -1){

2134

ret_errno = errno;

2135

perror_plus("socket");

2136

errno = old_errno;

2137

return ret_errno;

2138

}

2139

2140

if(quit_now){

2141

ret = close(sd);

2142

if(ret == -1){

2143

perror_plus("close");

2144

}

2145

errno = old_errno;

2146

return EINTR;

2147

}

2148

2149

if(debug){

2150

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

2151

interface);

2152

}

2153

2154

/* Raise privileges */

2155

ret_errno = raise_privileges();

2156

if(ret_errno != 0){

2157

errno = ret_errno;

2158

perror_plus("Failed to raise privileges");

2159

}

2160

2161

#ifdef __linux__

2162

int ret_linux;

2163

bool restore_loglevel = false;

2164

if(ret_errno == 0){

2165

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2166

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

2167

ret_linux = klogctl(8, NULL, 5);

2168

if(ret_linux == -1){

2169

perror_plus("klogctl");

2170

} else {

2171

restore_loglevel = true;

2172

}

2173

}

2174

#endif /* __linux__ */

2175

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

2176

ioctl_errno = errno;

2177

#ifdef __linux__

2178

if(restore_loglevel){

2179

ret_linux = klogctl(7, NULL, 0);

2180

if(ret_linux == -1){

2181

perror_plus("klogctl");

2182

}

2183

}

2184

#endif /* __linux__ */

2185

2186

/* If raise_privileges() succeeded above */

2187

if(ret_errno == 0){

2188

/* Lower privileges */

2189

ret_errno = lower_privileges();

2190

if(ret_errno != 0){

2191

errno = ret_errno;

2192

perror_plus("Failed to lower privileges");

2193

}

2194

}

2195

2196

/* Close the socket */

2197

ret = close(sd);

2198

if(ret == -1){

2199

perror_plus("close");

2200

}

2201

2202

if(ret_setflags == -1){

2203

errno = ioctl_errno;

2204

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2205

errno = old_errno;

2206

return ioctl_errno;

2207

}

2208

} else if(debug){

2209

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

2210

interface);

2211

}

2212

2213

/* Sleep checking until interface is running.

2214

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

2215

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

2216

if(interface_is_running(interface)){

2217

break;

2218

}

2219

struct timespec sleeptime = { .tv_nsec = 250000000 };

2220

ret = nanosleep(&sleeptime, NULL);

2221

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

2222

perror_plus("nanosleep");

2223

}

2224

}

2225

2226

errno = old_errno;

2227

return 0;

2228

}

2229

2230

__attribute__((nonnull, warn_unused_result))

2231

int take_down_interface(const char *const interface){

2232

int old_errno = errno;

2233

struct ifreq network;

2234

unsigned int if_index = if_nametoindex(interface);

2235

if(if_index == 0){

2236

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

2237

errno = old_errno;

2238

return ENXIO;

2239

}

2240

if(interface_is_up(interface)){

2241

int ret_errno = 0;

2242

int ioctl_errno = 0;

2243

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

2244

ret_errno = errno;

2245

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

2246

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

2247

errno = old_errno;

2248

return ret_errno;

2249

}

2250

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

2251

2252

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

2253

if(sd == -1){

2254

ret_errno = errno;

2255

perror_plus("socket");

2256

errno = old_errno;

2257

return ret_errno;

2258

}

2259

2260

if(debug){

2261

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

2262

interface);

2263

}

2264

2265

/* Raise privileges */

2266

ret_errno = raise_privileges();

2267

if(ret_errno != 0){

2268

errno = ret_errno;

2269

perror_plus("Failed to raise privileges");

2270

}

2271

2272

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

2273

ioctl_errno = errno;

2274

2275

/* If raise_privileges() succeeded above */

2276

if(ret_errno == 0){

2277

/* Lower privileges */

2278

ret_errno = lower_privileges();

2279

if(ret_errno != 0){

2280

errno = ret_errno;

2281

perror_plus("Failed to lower privileges");

2282

}

2283

}

2284

2285

/* Close the socket */

2286

int ret = close(sd);

2287

if(ret == -1){

2288

perror_plus("close");

2289

}

2290

2291

if(ret_setflags == -1){

2292

errno = ioctl_errno;

2293

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2294

errno = old_errno;

2295

return ioctl_errno;

2296

}

2297

} else if(debug){

2298

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

2299

interface);

2300

}

2301

2302

errno = old_errno;

2303

return 0;

1484

2304

}

1485

2305

1486

2306

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

2307

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

2308

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

2309

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

2310

.current_server = NULL, .interfaces = NULL,

2311

.interfaces_size = 0 };

1487

2312

AvahiSServiceBrowser *sb = NULL;

1488

int error;

2313

error_t ret_errno;

1489

2314

int ret;

1490

2315

intmax_t tmpmax;

1491

2316

char *tmp;

1492

2317

int exitcode = EXIT_SUCCESS;

1493

const char *interface = "";

1494

struct ifreq network;

1495

int sd = -1;

1496

bool take_down_interface = false;

1497

uid_t uid;

1498

gid_t gid;

1499

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

1500

bool tempdir_created = false;

2318

char *interfaces_to_take_down = NULL;

2319

size_t interfaces_to_take_down_size = 0;

2320

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

2321

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

2322

char *tempdir = NULL;

1501

2323

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1502

2324

const char *seckey = PATHDIR "/" SECKEY;

1503

2325

const char *pubkey = PATHDIR "/" PUBKEY;

2326

const char *dh_params_file = NULL;

2327

char *interfaces_hooks = NULL;

1504

2328

1505

2329

bool gnutls_initialized = false;

1506

2330

bool gpgme_initialized = false;

1558

2382

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

1559

2383

" Diffie-Hellman key exchange",

1560

2384

.group = 2 },

2385

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

2386

.arg = "FILE",

2387

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

2388

" for the Diffie-Hellman key exchange",

2389

.group = 2 },

1561

2390

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

1562

2391

.arg = "STRING",

1563

2392

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

1568

2397

.group = 2 },

1569

2398

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

1570

2399

.arg = "SECONDS",

1571

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

2400

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

1572

2401

.group = 2 },

1573

2402

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

1574

2403

.arg = "DIR",

1597

2426

connect_to = arg;

1598

2427

break;

1599

2428

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

1600

interface = arg;

2429

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

2430

arg, (int)',');

2431

if(ret_errno != 0){

2432

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

2433

}

1601

2434

break;

1602

2435

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

1603

2436

seckey = arg;

1614

2447

}

1615

2448

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

1616

2449

break;

2450

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

2451

dh_params_file = arg;

2452

break;

1617

2453

case 130: /* --priority */

1618

2454

mc.priority = arg;

1619

2455

break;

1646

2482

argp_state_help(state, state->out_stream,

1647

2483

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1648

2484

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

1651

2485

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

1652

2486

exit(argp_err_exit_status);

1653

2487

break;

1661

2495

.args_doc = "",

1662

2496

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

1663

2497

" passwords from a Mandos server" };

1664

ret = argp_parse(&argp, argc, argv,

1665

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1666

switch(ret){

2498

ret_errno = argp_parse(&argp, argc, argv,

2499

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2500

switch(ret_errno){

1667

2501

case 0:

1668

2502

break;

1669

2503

case ENOMEM:

1670

2504

default:

1671

errno = ret;

2505

errno = ret_errno;

1672

2506

perror_plus("argp_parse");

1673

2507

exitcode = EX_OSERR;

1674

2508

goto end;

1677

2511

goto end;

1678

2512

}

1679

2513

}

1680

1681

if(getuid() == 0){

2514

2515

{

1682

2516

/* Work around Debian bug #633582:

1683

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

1684

struct stat st;

1685

1686

/* Re-raise priviliges */

1687

errno = 0;

1688

ret = seteuid(0);

1689

if(ret == -1){

1690

perror_plus("seteuid");

1691

}

1692

1693

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

1694

int seckey_fd = open(seckey, O_RDONLY);

1695

if(seckey_fd == -1){

1696

perror_plus("open");

1697

} else {

1698

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

1699

if(ret == -1){

1700

perror_plus("fstat");

1701

} else {

1702

if(S_ISREG(st.st_mode)

1703

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

1704

ret = fchown(seckey_fd, uid, gid);

1705

if(ret == -1){

1706

perror_plus("fchown");

1707

}

1708

}

1709

}

1710

TEMP_FAILURE_RETRY(close(seckey_fd));

1711

}

1712

}

1713

1714

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

1715

int pubkey_fd = open(pubkey, O_RDONLY);

1716

if(pubkey_fd == -1){

1717

perror_plus("open");

1718

} else {

1719

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

1720

if(ret == -1){

1721

perror_plus("fstat");

1722

} else {

1723

if(S_ISREG(st.st_mode)

1724

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

1725

ret = fchown(pubkey_fd, uid, gid);

1726

if(ret == -1){

1727

perror_plus("fchown");

1728

}

1729

}

1730

}

1731

TEMP_FAILURE_RETRY(close(pubkey_fd));

1732

}

1733

}

1734

1735

/* Lower privileges */

1736

errno = 0;

1737

ret = seteuid(uid);

1738

if(ret == -1){

1739

perror_plus("seteuid");

2517

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

2518

2519

/* Re-raise privileges */

2520

ret = raise_privileges();

2521

if(ret != 0){

2522

errno = ret;

2523

perror_plus("Failed to raise privileges");

2524

} else {

2525

struct stat st;

2526

2527

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

2528

int seckey_fd = open(seckey, O_RDONLY);

2529

if(seckey_fd == -1){

2530

perror_plus("open");

2531

} else {

2532

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

2533

if(ret == -1){

2534

perror_plus("fstat");

2535

} else {

2536

if(S_ISREG(st.st_mode)

2537

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

2538

ret = fchown(seckey_fd, uid, gid);

2539

if(ret == -1){

2540

perror_plus("fchown");

2541

}

2542

}

2543

}

2544

close(seckey_fd);

2545

}

2546

}

2547

2548

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

2549

int pubkey_fd = open(pubkey, O_RDONLY);

2550

if(pubkey_fd == -1){

2551

perror_plus("open");

2552

} else {

2553

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

2554

if(ret == -1){

2555

perror_plus("fstat");

2556

} else {

2557

if(S_ISREG(st.st_mode)

2558

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

2559

ret = fchown(pubkey_fd, uid, gid);

2560

if(ret == -1){

2561

perror_plus("fchown");

2562

}

2563

}

2564

}

2565

close(pubkey_fd);

2566

}

2567

}

2568

2569

if(dh_params_file != NULL

2570

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

2571

int dhparams_fd = open(dh_params_file, O_RDONLY);

2572

if(dhparams_fd == -1){

2573

perror_plus("open");

2574

} else {

2575

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

2576

if(ret == -1){

2577

perror_plus("fstat");

2578

} else {

2579

if(S_ISREG(st.st_mode)

2580

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

2581

ret = fchown(dhparams_fd, uid, gid);

2582

if(ret == -1){

2583

perror_plus("fchown");

2584

}

2585

}

2586

}

2587

close(dhparams_fd);

2588

}

2589

}

2590

2591

/* Lower privileges */

2592

ret = lower_privileges();

2593

if(ret != 0){

2594

errno = ret;

2595

perror_plus("Failed to lower privileges");

2596

}

2597

}

2598

}

2599

2600

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

2601

{

2602

char *interface = NULL;

2603

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

2604

interface))){

2605

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

2606

and if_nametoindex(interface) == 0){

2607

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

2608

fprintf_plus(stderr, "Not using nonexisting interface"

2609

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

2610

}

2611

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

2612

interface = NULL;

2613

}

1740

2614

}

1741

2615

}

1742

2616

1743

2617

/* Run network hooks */

1744

2618

{

1745

if(getuid() == 0){

1746

/* Re-raise priviliges */

1747

errno = 0;

1748

ret = seteuid(0);

1749

if(ret == -1){

1750

perror_plus("seteuid");

1751

}

1752

}

1753

if(not run_network_hooks("start", interface, delay)){

1754

goto end;

1755

}

1756

if(getuid() == 0){

1757

/* Lower privileges */

1758

errno = 0;

1759

ret = seteuid(uid);

1760

if(ret == -1){

1761

perror_plus("seteuid");

1762

}

1763

}

2619

if(mc.interfaces != NULL){

2620

interfaces_hooks = malloc(mc.interfaces_size);

2621

if(interfaces_hooks == NULL){

2622

perror_plus("malloc");

2623

goto end;

2624

}

2625

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

2626

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

2627

}

2628

run_network_hooks("start", interfaces_hooks != NULL ?

2629

interfaces_hooks : "", delay);

1764

2630

}

1765

2631

1766

2632

if(not debug){

1767

2633

avahi_set_log_function(empty_log);

1768

2634

}

1769

2635

1770

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

1771

struct dirent **direntries;

1772

/* First look for interfaces that are up */

1773

ret = scandir(sys_class_net, &direntries, up_interface,

1774

alphasort);

1775

if(ret == 0){

1776

/* No up interfaces, look for any good interfaces */

1777

free(direntries);

1778

ret = scandir(sys_class_net, &direntries, good_interface,

1779

alphasort);

1780

}

1781

if(ret >= 1){

1782

/* Pick the first interface returned */

1783

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

1784

if(debug){

1785

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

1786

}

1787

if(interface == NULL){

1788

perror_plus("malloc");

1789

free(direntries);

1790

exitcode = EXIT_FAILURE;

1791

goto end;

1792

}

1793

free(direntries);

1794

} else {

1795

free(direntries);

1796

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

1797

exitcode = EXIT_FAILURE;

1798

goto end;

1799

}

1800

}

1801

1802

2636

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

1803

2637

from the signal handler */

1804

2638

/* Initialize the pseudo-RNG for Avahi */

1805

2639

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

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2640

simple_poll = avahi_simple_poll_new();

2641

if(simple_poll == NULL){

1808

2642

fprintf_plus(stderr,

1809

2643

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

1810

2644

exitcode = EX_UNAVAILABLE;

1874

2708

}

1875

2709

}

1876

2710

1877

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

1878

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

1879

if_index = (AvahiIfIndex) if_nametoindex(interface);

1880

if(if_index == 0){

1881

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

1882

exitcode = EX_UNAVAILABLE;

1883

goto end;

1884

}

1885

1886

if(quit_now){

1887

goto end;

1888

}

1889

1890

/* Re-raise priviliges */

1891

errno = 0;

1892

ret = seteuid(0);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

1897

#ifdef __linux__

1898

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1899

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

1900

ret = klogctl(8, NULL, 5);

1901

bool restore_loglevel = true;

1902

if(ret == -1){

1903

restore_loglevel = false;

1904

perror_plus("klogctl");

1905

}

1906

#endif /* __linux__ */

1907

1908

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1909

if(sd < 0){

1910

perror_plus("socket");

1911

exitcode = EX_OSERR;

1912

#ifdef __linux__

1913

if(restore_loglevel){

1914

ret = klogctl(7, NULL, 0);

1915

if(ret == -1){

1916

perror_plus("klogctl");

1917

}

1918

}

1919

#endif /* __linux__ */

1920

/* Lower privileges */

1921

errno = 0;

1922

ret = seteuid(uid);

1923

if(ret == -1){

1924

perror_plus("seteuid");

1925

}

1926

goto end;

1927

}

1928

strcpy(network.ifr_name, interface);

1929

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

1930

if(ret == -1){

1931

perror_plus("ioctl SIOCGIFFLAGS");

1932

#ifdef __linux__

1933

if(restore_loglevel){

1934

ret = klogctl(7, NULL, 0);

1935

if(ret == -1){

1936

perror_plus("klogctl");

1937

}

1938

}

1939

#endif /* __linux__ */

1940

exitcode = EX_OSERR;

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

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

1950

network.ifr_flags |= IFF_UP;

1951

take_down_interface = true;

1952

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

1953

if(ret == -1){

1954

take_down_interface = false;

1955

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1956

exitcode = EX_OSERR;

1957

#ifdef __linux__

1958

if(restore_loglevel){

1959

ret = klogctl(7, NULL, 0);

1960

if(ret == -1){

1961

perror_plus("klogctl");

2711

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

2712

if(mc.interfaces == NULL){

2713

struct dirent **direntries = NULL;

2714

/* Look for any good interfaces */

2715

ret = scandir(sys_class_net, &direntries, good_interface,

2716

alphasort);

2717

if(ret >= 1){

2718

/* Add all found interfaces to interfaces list */

2719

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

2720

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

2721

direntries[i]->d_name);

2722

if(ret_errno != 0){

2723

errno = ret_errno;

2724

perror_plus("argz_add");

2725

free(direntries[i]);

2726

continue;

2727

}

2728

if(debug){

2729

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

2730

direntries[i]->d_name);

2731

}

2732

free(direntries[i]);

2733

}

2734

free(direntries);

2735

} else {

2736

if(ret == 0){

2737

free(direntries);

2738

}

2739

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

2740

exitcode = EXIT_FAILURE;

2741

goto end;

2742

}

2743

}

2744

2745

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

2746

{

2747

char *interface = NULL;

2748

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

2749

interface))){

2750

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

2751

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

2752

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

2753

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

2754

interface);

2755

interface = NULL;

2756

while((interface = argz_next(mc.interfaces,

2757

mc.interfaces_size, interface))){

2758

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

2759

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

2760

interface);

2761

interface = NULL;

1962

2762

}

1963

2763

}

1964

#endif /* __linux__ */

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

}

1974

/* Sleep checking until interface is running.

1975

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

1976

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

1977

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

1978

if(ret == -1){

1979

perror_plus("ioctl SIOCGIFFLAGS");

1980

} else if(network.ifr_flags & IFF_RUNNING){

1981

2764

break;

1982

2765

}

1983

struct timespec sleeptime = { .tv_nsec = 250000000 };

1984

ret = nanosleep(&sleeptime, NULL);

1985

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

1986

perror_plus("nanosleep");

1987

}

1988

}

1989

if(not take_down_interface){

1990

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

1991

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

1992

if(ret == -1){

1993

perror_plus("close");

1994

}

1995

}

1996

#ifdef __linux__

1997

if(restore_loglevel){

1998

/* Restores kernel loglevel to default */

1999

ret = klogctl(7, NULL, 0);

2000

if(ret == -1){

2001

perror_plus("klogctl");

2002

}

2003

}

2004

#endif /* __linux__ */

2005

/* Lower privileges */

2006

errno = 0;

2007

/* Lower privileges */

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2011

}

2766

bool interface_was_up = interface_is_up(interface);

2767

errno = bring_up_interface(interface, delay);

2768

if(not interface_was_up){

2769

if(errno != 0){

2770

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

2771

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

2772

} else {

2773

errno = argz_add(&interfaces_to_take_down,

2774

&interfaces_to_take_down_size,

2775

interface);

2776

if(errno != 0){

2777

perror_plus("argz_add");

2778

}

2779

}

2780

}

2781

}

2782

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

2783

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

2784

}

2785

}

2786

2787

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

2788

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

2789

if(debug){

2790

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

2791

mc.interfaces);

2792

}

2793

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

2012

2794

}

2013

2795

2014

2796

if(quit_now){

2015

2797

goto end;

2016

2798

}

2017

2799

2018

ret = init_gnutls_global(pubkey, seckey);

2800

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

2019

2801

if(ret == -1){

2020

2802

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

2021

2803

exitcode = EX_UNAVAILABLE;

2028

2810

goto end;

2029

2811

}

2030

2812

2031

if(mkdtemp(tempdir) == NULL){

2813

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

2814

tempdir = mkdtemp(run_tempdir);

2815

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

2816

if(debug){

2817

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

2818

run_tempdir, old_tempdir);

2819

}

2820

tempdir = mkdtemp(old_tempdir);

2821

}

2822

if(tempdir == NULL){

2032

2823

perror_plus("mkdtemp");

2033

2824

goto end;

2034

2825

}

2035

tempdir_created = true;

2036

2826

2037

2827

if(quit_now){

2038

2828

goto end;

2039

2829

}

2040

2830

2041

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

2831

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

2042

2832

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

2043

2833

exitcode = EX_UNAVAILABLE;

2044

2834

goto end;

2054

2844

/* Connect directly, do not use Zeroconf */

2055

2845

/* (Mainly meant for debugging) */

2056

2846

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

2847

2057

2848

if(address == NULL){

2058

2849

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

2059

2850

exitcode = EX_USAGE;

2064

2855

goto end;

2065

2856

}

2066

2857

2067

uint16_t port;

2858

in_port_t port;

2068

2859

errno = 0;

2069

2860

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

2070

2861

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

2071

or tmpmax != (uint16_t)tmpmax){

2862

or tmpmax != (in_port_t)tmpmax){

2072

2863

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

2073

2864

exitcode = EX_USAGE;

2074

2865

goto end;

2075

2866

}

2076

2867

2077

2868

if(quit_now){

2078

2869

goto end;

2079

2870

}

2080

2871

2081

port = (uint16_t)tmpmax;

2872

port = (in_port_t)tmpmax;

2082

2873

*address = '\0';

2083

2874

/* Colon in address indicates IPv6 */

2084

2875

int af;

2100

2891

}

2101

2892

2102

2893

while(not quit_now){

2103

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

2894

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

2895

&mc);

2104

2896

if(quit_now or ret == 0){

2105

2897

break;

2106

2898

}

2108

2900

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

2109

2901

(int)retry_interval);

2110

2902

}

2111

sleep((int)retry_interval);

2903

sleep((unsigned int)retry_interval);

2112

2904

}

2113

2905

2114

if (not quit_now){

2906

if(not quit_now){

2115

2907

exitcode = EXIT_SUCCESS;

2116

2908

}

2117

2909

2132

2924

config.publish_domain = 0;

2133

2925

2134

2926

/* Allocate a new server */

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2927

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2928

&config, NULL, NULL, &ret);

2138

2929

2139

2930

/* Free the Avahi configuration data */

2140

2931

avahi_server_config_free(&config);

2143

2934

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

2144

2935

if(mc.server == NULL){

2145

2936

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

2146

avahi_strerror(error));

2937

avahi_strerror(ret));

2147

2938

exitcode = EX_UNAVAILABLE;

2148

2939

goto end;

2149

2940

}

2155

2946

/* Create the Avahi service browser */

2156

2947

sb = avahi_s_service_browser_new(mc.server, if_index,

2157

2948

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2158

NULL, 0, browse_callback, NULL);

2949

NULL, 0, browse_callback,

2950

(void *)&mc);

2159

2951

if(sb == NULL){

2160

2952

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

2161

2953

avahi_strerror(avahi_server_errno(mc.server)));

2172

2964

if(debug){

2173

2965

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

2174

2966

}

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2967

2968

ret = avahi_loop_with_timeout(simple_poll,

2969

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

2178

2970

if(debug){

2179

2971

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

2180

2972

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

2183

2975

end:

2184

2976

2185

2977

if(debug){

2186

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

2978

if(signal_received){

2979

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

2980

argv[0], signal_received,

2981

strsignal(signal_received));

2982

} else {

2983

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

2984

}

2187

2985

}

2188

2986

2189

2987

/* Cleanup things */

2988

free(mc.interfaces);

2989

2190

2990

if(sb != NULL)

2191

2991

avahi_s_service_browser_free(sb);

2192

2992

2193

2993

if(mc.server != NULL)

2194

2994

avahi_server_free(mc.server);

2195

2995

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

2996

if(simple_poll != NULL)

2997

avahi_simple_poll_free(simple_poll);

2198

2998

2199

2999

if(gnutls_initialized){

2200

3000

gnutls_certificate_free_credentials(mc.cred);

2201

gnutls_global_deinit();

2202

3001

gnutls_dh_params_deinit(mc.dh_params);

2203

3002

}

2204

3003

2212

3011

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

2213

3012

while(mc.current_server != NULL){

2214

3013

server *next = mc.current_server->next;

3014

#ifdef __GNUC__

3015

#pragma GCC diagnostic push

3016

#pragma GCC diagnostic ignored "-Wcast-qual"

3017

#endif

3018

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

3019

#ifdef __GNUC__

3020

#pragma GCC diagnostic pop

3021

#endif

2215

3022

free(mc.current_server);

2216

3023

mc.current_server = next;

2217

3024

}

2218

3025

}

2219

3026

2220

/* Re-raise priviliges */

3027

/* Re-raise privileges */

2221

3028

{

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

3029

ret = raise_privileges();

3030

if(ret != 0){

3031

errno = ret;

3032

perror_plus("Failed to raise privileges");

3033

} else {

3034

3035

/* Run network hooks */

3036

run_network_hooks("stop", interfaces_hooks != NULL ?

3037

interfaces_hooks : "", delay);

3038

3039

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

3040

{

3041

char *interface = NULL;

3042

while((interface = argz_next(interfaces_to_take_down,

3043

interfaces_to_take_down_size,

3044

interface))){

3045

ret = take_down_interface(interface);

3046

if(ret != 0){

3047

errno = ret;

3048

perror_plus("Failed to take down interface");

3049

}

3050

}

3051

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

3052

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

3053

" down\n");

3054

}

2227

3055

}

2228

3056

}

2229

3057

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Take down the network interface */

2234

if(take_down_interface and geteuid() == 0){

2235

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

2236

if(ret == -1){

2237

perror_plus("ioctl SIOCGIFFLAGS");

2238

} else if(network.ifr_flags & IFF_UP){

2239

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

2240

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

2241

if(ret == -1){

2242

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2243

}

2244

}

2245

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

2246

if(ret == -1){

2247

perror_plus("close");

2248

}

3058

ret = lower_privileges_permanently();

3059

if(ret != 0){

3060

errno = ret;

3061

perror_plus("Failed to lower privileges permanently");

2249

3062

}

2250

3063

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

3064

3065

free(interfaces_to_take_down);

3066

free(interfaces_hooks);

3067

3068

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

3069

uintmax_t level){

3070

struct dirent **direntries = NULL;

3071

int dret;

3072

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

3073

O_RDONLY

3074

| O_NOFOLLOW

3075

| O_DIRECTORY

3076

| O_PATH));

3077

if(dir_fd == -1){

3078

perror_plus("open");

3079

return;

3080

}

3081

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

3082

notdotentries, alphasort);

3083

if(numentries >= 0){

3084

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

3085

if(debug){

3086

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

3087

dirname, direntries[i]->d_name);

3088

}

3089

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

3090

if(dret == -1){

3091

if(errno == EISDIR){

3092

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

3093

AT_REMOVEDIR);

3094

}

3095

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

3096

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

3097

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

3098

/* Recurse only in this special case */

3099

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

3100

dret = 0;

3101

}

3102

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

3103

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

3104

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

3105

}

3106

}

3107

free(direntries[i]);

3108

}

3109

3110

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

3111

free(direntries);

3112

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3113

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

3114

perror_plus("rmdir");

3115

}

3116

} else {

3117

perror_plus("scandirat");

3118

}

3119

close(dir_fd);

2258

3120

}

2259

3121

2260

3122

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

2261

if(tempdir_created){

2262

struct dirent **direntries = NULL;

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

2267

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

2268

direntry = direntries[i];

2269

char *fullname = NULL;

2270

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

2271

direntry->d_name);

2272

if(ret < 0){

2273

perror_plus("asprintf");

2274

continue;

2275

}

2276

ret = remove(fullname);

2277

if(ret == -1){

2278

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

2279

strerror(errno));

2280

}

2281

free(fullname);

2282

}

2283

}

2284

2285

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

2286

free(direntries);

2287

if (numentries == -1){

2288

perror_plus("scandir");

2289

}

2290

ret = rmdir(tempdir);

2291

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

2292

perror_plus("rmdir");

2293

}

3123

if(tempdir != NULL){

3124

clean_dir_at(-1, tempdir, 0);

2294

3125

}

2295

3126

2296

3127

if(quit_now){