/mandos/trunk : revision 505.3.14

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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 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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*

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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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21

* WITHOUT ANY WARRANTY; without even the implied warranty of

24

22

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

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23

* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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*

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

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30

*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

45

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

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stdout, ferror(), remove() */

44

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

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

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

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strtof(), abort() */

49

48

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

50

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

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asprintf(), strncpy(), strsignal()

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*/

49

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

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

53

51

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

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52

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

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53

sockaddr_in6, PF_INET6,

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55

opendir(), DIR */

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56

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

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

60

inet_pton(), connect(),

61

getnameinfo() */

62

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

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inet_pton(), connect() */

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

63

60

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

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61

*/

65

62

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

66

63

strtoimax() */

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

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

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66

program_invocation_short_name */

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

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

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73

*/

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74

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

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

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

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unlinkat() */

84

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

76

setgid(), pause() */

77

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

85

78

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

86

79

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

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80

argp_state, struct argp,

94

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

95

88

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

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89

WEXITSTATUS(), WTERMSIG() */

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

98

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

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argz_delete(), argz_append(),

100

argz_stringify(), argz_add(),

101

argz_count() */

102

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

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EAI_SYSTEM, gai_strerror() */

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90

105

91

#ifdef __linux__

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92

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

148

134

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

149

135

char *connect_to = NULL;

150

136

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

152

uid_t uid = 65534;

153

gid_t gid = 65534;

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137

155

138

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

156

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typedef struct server{

157

140

const char *ip;

158

in_port_t port;

141

uint16_t port;

159

142

AvahiIfIndex if_index;

160

143

int af;

161

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struct timespec last_seen;

165

148

166

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

167

150

typedef struct {

151

AvahiSimplePoll *simple_poll;

168

152

AvahiServer *server;

169

153

gnutls_certificate_credentials_t cred;

170

154

unsigned int dh_bits;

172

156

const char *priority;

173

157

gpgme_ctx_t ctx;

174

158

server *current_server;

175

char *interfaces;

176

size_t interfaces_size;

177

159

} mandos_context;

178

160

179

/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

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 };

181

166

182

167

sig_atomic_t quit_now = 0;

183

168

int signal_received = 0;

184

169

185

170

/* Function to use when printing errors */

186

171

void perror_plus(const char *print_text){

187

int e = errno;

188

172

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

189

173

program_invocation_short_name);

190

errno = e;

191

174

perror(print_text);

192

175

}

193

176

194

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

195

177

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

196

178

va_list ap;

197

179

va_start (ap, format);

198

180

199

181

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

200

182

program_invocation_short_name));

201

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

183

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

202

184

}

203

185

204

186

/*

206

188

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

207

189

* "buffer_length" is how much is already used.

208

190

*/

209

__attribute__((nonnull, warn_unused_result))

210

191

size_t incbuffer(char **buffer, size_t buffer_length,

211

192

size_t buffer_capacity){

212

193

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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;

194

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

195

if(buffer == NULL){

219

196

return 0;

220

197

}

221

*buffer = new_buf;

222

198

buffer_capacity += BUFFER_SIZE;

223

199

}

224

200

return buffer_capacity;

225

201

}

226

202

227

203

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

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){

204

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

205

int af){

231

206

int ret;

232

207

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

233

208

if(new_server == NULL){

234

209

perror_plus("malloc");

235

return false;

210

return -1;

236

211

}

237

212

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

238

213

.port = port,

240

215

.af = af };

241

216

if(new_server->ip == NULL){

242

217

perror_plus("strdup");

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;

218

return -1;

259

219

}

260

220

/* Special case of first server */

261

if(*current_server == NULL){

221

if (mc.current_server == NULL){

262

222

new_server->next = new_server;

263

223

new_server->prev = new_server;

264

*current_server = new_server;

224

mc.current_server = new_server;

225

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

265

226

} else {

266

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

267

new_server->next = *current_server;

268

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

227

new_server->next = mc.current_server;

228

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

269

229

new_server->prev->next = new_server;

270

(*current_server)->prev = new_server;

271

}

272

return true;

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;

273

238

}

274

239

275

240

/*

276

241

* Initialize GPGME.

277

242

*/

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){

243

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

244

const char *tempdir){

283

245

gpgme_error_t rc;

284

246

gpgme_engine_info_t engine_info;

285

247

248

286

249

/*

287

250

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

288

251

*/

289

bool import_key(const char * const filename){

252

bool import_key(const char *filename){

290

253

int ret;

291

254

int fd;

292

255

gpgme_data_t pgp_data;

304

267

return false;

305

268

}

306

269

307

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

270

rc = gpgme_op_import(mc.ctx, pgp_data);

308

271

if(rc != GPG_ERR_NO_ERROR){

309

272

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

310

273

gpgme_strsource(rc), gpgme_strerror(rc));

311

274

return false;

312

275

}

313

276

314

ret = close(fd);

277

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

315

278

if(ret == -1){

316

279

perror_plus("close");

317

280

}

354

317

}

355

318

356

319

/* Create new GPGME "context" */

357

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

320

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

358

321

if(rc != GPG_ERR_NO_ERROR){

359

322

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

360

323

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

373

336

* Decrypt OpenPGP data.

374

337

* Returns -1 on error

375

338

*/

376

__attribute__((nonnull, warn_unused_result))

377

339

static ssize_t pgp_packet_decrypt(const char *cryptotext,

378

340

size_t crypto_size,

379

char **plaintext,

380

mandos_context *mc){

341

char **plaintext){

381

342

gpgme_data_t dh_crypto, dh_plain;

382

343

gpgme_error_t rc;

383

344

ssize_t ret;

409

370

410

371

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

411

372

data buffer */

412

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

373

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

413

374

if(rc != GPG_ERR_NO_ERROR){

414

375

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

415

376

gpgme_strsource(rc), gpgme_strerror(rc));

416

377

plaintext_length = -1;

417

378

if(debug){

418

379

gpgme_decrypt_result_t result;

419

result = gpgme_op_decrypt_result(mc->ctx);

380

result = gpgme_op_decrypt_result(mc.ctx);

420

381

if(result == NULL){

421

382

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

422

383

} else {

423

if(result->unsupported_algorithm != NULL) {

424

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

425

result->unsupported_algorithm);

426

}

384

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

385

result->unsupported_algorithm);

427

386

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

428

387

result->wrong_key_usage);

429

388

if(result->file_name != NULL){

501

460

return plaintext_length;

502

461

}

503

462

504

__attribute__((warn_unused_result, const))

505

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

506

if(str == NULL)

507

return "(unknown)";

508

return str;

509

}

510

511

__attribute__((warn_unused_result))

512

static const char *safer_gnutls_strerror(int value){

513

const char *ret = gnutls_strerror(value);

514

return safe_string(ret);

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;

515

469

}

516

470

517

471

/* GnuTLS log function callback */

518

__attribute__((nonnull))

519

472

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

520

473

const char* string){

521

474

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

522

475

}

523

476

524

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

525

477

static int init_gnutls_global(const char *pubkeyfilename,

526

const char *seckeyfilename,

527

const char *dhparamsfilename,

528

mandos_context *mc){

478

const char *seckeyfilename){

529

479

int ret;

530

unsigned int uret;

531

480

532

481

if(debug){

533

482

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

534

483

}

535

484

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

536

492

if(debug){

537

493

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

538

494

* - GnuTLS manual

542

498

}

543

499

544

500

/* OpenPGP credentials */

545

ret = gnutls_certificate_allocate_credentials(&mc->cred);

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

546

502

if(ret != GNUTLS_E_SUCCESS){

547

503

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

548

504

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

549

506

return -1;

550

507

}

551

508

557

514

}

558

515

559

516

ret = gnutls_certificate_set_openpgp_key_file

560

(mc->cred, pubkeyfilename, seckeyfilename,

517

(mc.cred, pubkeyfilename, seckeyfilename,

561

518

GNUTLS_OPENPGP_FMT_BASE64);

562

519

if(ret != GNUTLS_E_SUCCESS){

563

520

fprintf_plus(stderr,

569

526

}

570

527

571

528

/* GnuTLS server initialization */

572

ret = gnutls_dh_params_init(&mc->dh_params);

529

ret = gnutls_dh_params_init(&mc.dh_params);

573

530

if(ret != GNUTLS_E_SUCCESS){

574

531

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

575

532

" initialization: %s\n",

576

533

safer_gnutls_strerror(ret));

577

534

goto globalfail;

578

535

}

579

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

580

if(dhparamsfilename != NULL){

581

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

582

do {

583

int dhpfile = open(dhparamsfilename, O_RDONLY);

584

if(dhpfile == -1){

585

perror_plus("open");

586

dhparamsfilename = NULL;

587

break;

588

}

589

size_t params_capacity = 0;

590

while(true){

591

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

592

(size_t)params.size,

593

(size_t)params_capacity);

594

if(params_capacity == 0){

595

perror_plus("incbuffer");

596

free(params.data);

597

params.data = NULL;

598

dhparamsfilename = NULL;

599

break;

600

}

601

ssize_t bytes_read = read(dhpfile,

602

params.data + params.size,

603

BUFFER_SIZE);

604

/* EOF */

605

if(bytes_read == 0){

606

break;

607

}

608

/* check bytes_read for failure */

609

if(bytes_read < 0){

610

perror_plus("read");

611

free(params.data);

612

params.data = NULL;

613

dhparamsfilename = NULL;

614

break;

615

}

616

params.size += (unsigned int)bytes_read;

617

}

618

ret = close(dhpfile);

619

if(ret == -1){

620

perror_plus("close");

621

}

622

if(params.data == NULL){

623

dhparamsfilename = NULL;

624

}

625

if(dhparamsfilename == NULL){

626

break;

627

}

628

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

629

GNUTLS_X509_FMT_PEM);

630

if(ret != GNUTLS_E_SUCCESS){

631

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

632

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

633

safer_gnutls_strerror(ret));

634

dhparamsfilename = NULL;

635

}

636

free(params.data);

637

} while(false);

638

}

639

if(dhparamsfilename == NULL){

640

if(mc->dh_bits == 0){

641

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

642

/* Try to read the private key file */

643

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

644

do {

645

int secfile = open(seckeyfilename, O_RDONLY);

646

if(secfile == -1){

647

perror_plus("open");

648

break;

649

}

650

size_t buffer_capacity = 0;

651

while(true){

652

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

653

(size_t)buffer.size,

654

(size_t)buffer_capacity);

655

if(buffer_capacity == 0){

656

perror_plus("incbuffer");

657

free(buffer.data);

658

buffer.data = NULL;

659

break;

660

}

661

ssize_t bytes_read = read(secfile,

662

buffer.data + buffer.size,

663

BUFFER_SIZE);

664

/* EOF */

665

if(bytes_read == 0){

666

break;

667

}

668

/* check bytes_read for failure */

669

if(bytes_read < 0){

670

perror_plus("read");

671

free(buffer.data);

672

buffer.data = NULL;

673

break;

674

}

675

buffer.size += (unsigned int)bytes_read;

676

}

677

close(secfile);

678

} while(false);

679

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

680

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

681

if(buffer.data != NULL){

682

{

683

gnutls_openpgp_privkey_t privkey = NULL;

684

ret = gnutls_openpgp_privkey_init(&privkey);

685

if(ret != GNUTLS_E_SUCCESS){

686

fprintf_plus(stderr, "Error initializing OpenPGP key"

687

" structure: %s",

688

safer_gnutls_strerror(ret));

689

free(buffer.data);

690

buffer.data = NULL;

691

} else {

692

ret = gnutls_openpgp_privkey_import

693

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

694

if(ret != GNUTLS_E_SUCCESS){

695

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

696

safer_gnutls_strerror(ret));

697

privkey = NULL;

698

}

699

free(buffer.data);

700

buffer.data = NULL;

701

if(privkey != NULL){

702

/* Use private key to suggest an appropriate

703

sec_param */

704

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

705

gnutls_openpgp_privkey_deinit(privkey);

706

if(debug){

707

fprintf_plus(stderr, "This OpenPGP key implies using"

708

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

709

safe_string(gnutls_sec_param_get_name

710

(sec_param)));

711

}

712

}

713

}

714

}

715

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

716

/* Err on the side of caution */

717

sec_param = GNUTLS_SEC_PARAM_ULTRA;

718

if(debug){

719

fprintf_plus(stderr, "Falling back to security parameter"

720

" \"%s\"\n",

721

safe_string(gnutls_sec_param_get_name

722

(sec_param)));

723

}

724

}

725

}

726

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

727

if(uret != 0){

728

mc->dh_bits = uret;

729

if(debug){

730

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

731

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

732

safe_string(gnutls_sec_param_get_name

733

(sec_param)),

734

mc->dh_bits);

735

}

736

} else {

737

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

738

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

739

safe_string(gnutls_sec_param_get_name

740

(sec_param)),

741

safer_gnutls_strerror(ret));

742

goto globalfail;

743

}

744

} else if(debug){

745

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

746

mc->dh_bits);

747

}

748

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

749

if(ret != GNUTLS_E_SUCCESS){

750

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

751

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

752

safer_gnutls_strerror(ret));

753

goto globalfail;

754

}

755

}

756

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

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);

757

544

758

545

return 0;

759

546

760

547

globalfail:

761

548

762

gnutls_certificate_free_credentials(mc->cred);

763

gnutls_dh_params_deinit(mc->dh_params);

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

764

552

return -1;

765

553

}

766

554

767

__attribute__((nonnull, warn_unused_result))

768

static int init_gnutls_session(gnutls_session_t *session,

769

mandos_context *mc){

555

static int init_gnutls_session(gnutls_session_t *session){

770

556

int ret;

771

557

/* GnuTLS session creation */

772

558

do {

784

570

{

785

571

const char *err;

786

572

do {

787

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

573

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

788

574

if(quit_now){

789

575

gnutls_deinit(*session);

790

576

return -1;

801

587

802

588

do {

803

589

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

804

mc->cred);

590

mc.cred);

805

591

if(quit_now){

806

592

gnutls_deinit(*session);

807

593

return -1;

817

603

/* ignore client certificate if any. */

818

604

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

819

605

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

820

608

return 0;

821

609

}

822

610

824

612

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

825

613

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

826

614

827

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

828

__attribute__((warn_unused_result))

829

int raise_privileges(void){

830

int old_errno = errno;

831

int ret = 0;

832

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

833

ret = errno;

834

}

835

errno = old_errno;

836

return ret;

837

}

838

839

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

840

__attribute__((warn_unused_result))

841

int raise_privileges_permanently(void){

842

int old_errno = errno;

843

int ret = raise_privileges();

844

if(ret != 0){

845

errno = old_errno;

846

return ret;

847

}

848

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

849

ret = errno;

850

}

851

errno = old_errno;

852

return ret;

853

}

854

855

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

856

__attribute__((warn_unused_result))

857

int lower_privileges(void){

858

int old_errno = errno;

859

int ret = 0;

860

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

861

ret = errno;

862

}

863

errno = old_errno;

864

return ret;

865

}

866

867

/* Lower privileges permanently */

868

__attribute__((warn_unused_result))

869

int lower_privileges_permanently(void){

870

int old_errno = errno;

871

int ret = 0;

872

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

873

ret = errno;

874

}

875

errno = old_errno;

876

return ret;

877

}

878

879

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

880

__attribute__((nonnull, warn_unused_result))

881

static bool add_delete_local_route(const bool add,

882

const char *address,

883

AvahiIfIndex if_index){

884

int ret;

885

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

886

char add_arg[] = "add";

887

char delete_arg[] = "delete";

888

char debug_flag[] = "--debug";

889

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

890

if(pluginhelperdir == NULL){

891

if(debug){

892

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

893

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

894

}

895

return false;

896

}

897

898

char interface[IF_NAMESIZE];

899

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

900

perror_plus("if_indextoname");

901

return false;

902

}

903

904

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

905

if(devnull == -1){

906

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

907

return false;

908

}

909

pid_t pid = fork();

910

if(pid == 0){

911

/* Child */

912

/* Raise privileges */

913

errno = raise_privileges_permanently();

914

if(errno != 0){

915

perror_plus("Failed to raise privileges");

916

/* _exit(EX_NOPERM); */

917

} else {

918

/* Set group */

919

errno = 0;

920

ret = setgid(0);

921

if(ret == -1){

922

perror_plus("setgid");

923

_exit(EX_NOPERM);

924

}

925

/* Reset supplementary groups */

926

errno = 0;

927

ret = setgroups(0, NULL);

928

if(ret == -1){

929

perror_plus("setgroups");

930

_exit(EX_NOPERM);

931

}

932

}

933

ret = dup2(devnull, STDIN_FILENO);

934

if(ret == -1){

935

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

936

_exit(EX_OSERR);

937

}

938

ret = close(devnull);

939

if(ret == -1){

940

perror_plus("close");

941

_exit(EX_OSERR);

942

}

943

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

944

if(ret == -1){

945

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

946

_exit(EX_OSERR);

947

}

948

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

949

O_RDONLY

950

| O_DIRECTORY

951

| O_PATH

952

| O_CLOEXEC));

953

if(helperdir_fd == -1){

954

perror_plus("open");

955

_exit(EX_UNAVAILABLE);

956

}

957

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

958

helper, O_RDONLY));

959

if(helper_fd == -1){

960

perror_plus("openat");

961

close(helperdir_fd);

962

_exit(EX_UNAVAILABLE);

963

}

964

close(helperdir_fd);

965

#ifdef __GNUC__

966

#pragma GCC diagnostic push

967

#pragma GCC diagnostic ignored "-Wcast-qual"

968

#endif

969

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

970

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

971

interface, debug ? debug_flag : NULL, NULL },

972

environ) == -1){

973

#ifdef __GNUC__

974

#pragma GCC diagnostic pop

975

#endif

976

perror_plus("fexecve");

977

_exit(EXIT_FAILURE);

978

}

979

}

980

if(pid == -1){

981

perror_plus("fork");

982

return false;

983

}

984

int status;

985

pid_t pret = -1;

986

errno = 0;

987

do {

988

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

989

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

990

int errno_raising = 0;

991

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

992

errno_raising = errno;

993

perror_plus("Failed to raise privileges in order to"

994

" kill helper program");

995

}

996

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

997

perror_plus("kill");

998

}

999

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

1000

perror_plus("Failed to lower privileges after killing"

1001

" helper program");

1002

}

1003

return false;

1004

}

1005

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

1006

if(pret == -1){

1007

perror_plus("waitpid");

1008

return false;

1009

}

1010

if(WIFEXITED(status)){

1011

if(WEXITSTATUS(status) != 0){

1012

fprintf_plus(stderr, "Error: iprouteadddel exited"

1013

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

1014

return false;

1015

}

1016

return true;

1017

}

1018

if(WIFSIGNALED(status)){

1019

fprintf_plus(stderr, "Error: iprouteadddel died by"

1020

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

1021

return false;

1022

}

1023

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

1024

return false;

1025

}

1026

1027

__attribute__((nonnull, warn_unused_result))

1028

static bool add_local_route(const char *address,

1029

AvahiIfIndex if_index){

1030

if(debug){

1031

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

1032

}

1033

return add_delete_local_route(true, address, if_index);

1034

}

1035

1036

__attribute__((nonnull, warn_unused_result))

1037

static bool delete_local_route(const char *address,

1038

AvahiIfIndex if_index){

1039

if(debug){

1040

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

1041

}

1042

return add_delete_local_route(false, address, if_index);

1043

}

1044

1045

615

/* Called when a Mandos server is found */

1046

__attribute__((nonnull, warn_unused_result))

1047

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

616

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

1048

617

AvahiIfIndex if_index,

1049

int af, mandos_context *mc){

618

int af){

1050

619

int ret, tcp_sd = -1;

1051

620

ssize_t sret;

1052

struct sockaddr_storage to;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1053

625

char *buffer = NULL;

1054

626

char *decrypted_buffer = NULL;

1055

627

size_t buffer_length = 0;

1058

630

int retval = -1;

1059

631

gnutls_session_t session;

1060

632

int pf; /* Protocol family */

1061

bool route_added = false;

1062

633

1063

634

errno = 0;

1064

635

1080

651

return -1;

1081

652

}

1082

653

1083

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

1084

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

1085

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

1086

bool match = false;

1087

{

1088

char *interface = NULL;

1089

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

1090

mc->interfaces_size,

1091

interface))){

1092

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

1093

match = true;

1094

break;

1095

}

1096

}

1097

}

1098

if(not match){

1099

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

1100

connect to the server */

1101

if(debug){

1102

char interface[IF_NAMESIZE];

1103

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

1104

perror_plus("if_indextoname");

1105

} else {

1106

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

1107

" \"%s\"\n",

1108

if_indextoname((unsigned int)if_index,

1109

interface));

1110

}

1111

}

1112

return -1;

1113

}

1114

}

1115

1116

ret = init_gnutls_session(&session, mc);

654

ret = init_gnutls_session(&session);

1117

655

if(ret != 0){

1118

656

return -1;

1119

657

}

1120

658

1121

659

if(debug){

1122

660

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

1123

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

661

PRIu16 "\n", ip, port);

1124

662

}

1125

663

1126

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

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1127

665

if(tcp_sd < 0){

1128

666

int e = errno;

1129

667

perror_plus("socket");

1136

674

goto mandos_end;

1137

675

}

1138

676

677

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

1139

678

if(af == AF_INET6){

1140

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

1141

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

1142

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

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1143

681

} else { /* IPv4 */

1144

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

1145

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

1146

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

682

to.in.sin_family = (sa_family_t)af;

683

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

1147

684

}

1148

685

if(ret < 0 ){

1149

686

int e = errno;

1158

695

goto mandos_end;

1159

696

}

1160

697

if(af == AF_INET6){

1161

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

1162

if(IN6_IS_ADDR_LINKLOCAL

1163

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

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*/

1164

705

if(if_index == AVAHI_IF_UNSPEC){

1165

706

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

1166

707

" incomplete without a network interface\n");

1168

709

goto mandos_end;

1169

710

}

1170

711

/* Set the network interface number as scope */

1171

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

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1172

713

}

1173

714

} else {

1174

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

715

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

716

-Wconversion and

717

-Wunreachable-code */

1175

718

}

1176

719

1177

720

if(quit_now){

1185

728

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

1186

729

perror_plus("if_indextoname");

1187

730

} else {

1188

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

1189

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

731

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

732

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

1190

733

}

1191

734

} else {

1192

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

1193

ip, (uintmax_t)port);

735

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

736

ip, port);

1194

737

}

1195

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1196

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1197

if(af == AF_INET6){

1198

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

1199

sizeof(struct sockaddr_in6),

1200

addrstr, sizeof(addrstr), NULL, 0,

1201

NI_NUMERICHOST);

1202

} else {

1203

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

1204

sizeof(struct sockaddr_in),

1205

addrstr, sizeof(addrstr), NULL, 0,

1206

NI_NUMERICHOST);

1207

}

1208

if(ret == EAI_SYSTEM){

1209

perror_plus("getnameinfo");

1210

} else if(ret != 0) {

1211

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

1212

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

1213

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

1214

}

1215

}

1216

1217

if(quit_now){

1218

errno = EINTR;

1219

goto mandos_end;

1220

}

1221

1222

while(true){

1223

if(af == AF_INET6){

1224

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

1225

sizeof(struct sockaddr_in6));

1226

} else {

1227

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

1228

sizeof(struct sockaddr_in));

1229

}

1230

if(ret < 0){

1231

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

1232

and if_index != AVAHI_IF_UNSPEC

1233

and connect_to == NULL

1234

and not route_added and

1235

((af == AF_INET6 and not

1236

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1237

&to)->sin6_addr)))

1238

or (af == AF_INET and

1239

/* Not a a IPv4LL address */

1240

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

1241

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

1242

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

1243

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

1244

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

1245

connect to a Mandos server announced by Avahi on a server

1246

host with a global address. Work around this by retrying

1247

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

1248

1249

Avahi bug reference:

1250

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

1251

https://bugs.debian.org/587961

1252

*/

1253

if(debug){

1254

fprintf_plus(stderr, "Mandos server unreachable, trying"

1255

" direct route\n");

1256

}

1257

int e = errno;

1258

route_added = add_local_route(ip, if_index);

1259

if(route_added){

1260

continue;

1261

}

1262

errno = e;

1263

}

1264

if(errno != ECONNREFUSED or debug){

1265

int e = errno;

1266

perror_plus("connect");

1267

errno = e;

1268

}

1269

goto mandos_end;

1270

}

1271

1272

if(quit_now){

1273

errno = EINTR;

1274

goto mandos_end;

1275

}

1276

break;

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;

1277

779

}

1278

780

1279

781

const char *out = mandos_protocol_version;

1315

817

goto mandos_end;

1316

818

}

1317

819

1318

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

1319

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

1320

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

1321

gnutls_transport_set_ptr(session,

1322

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1323

822

1324

823

if(quit_now){

1325

824

errno = EINTR;

1430

929

if(buffer_length > 0){

1431

930

ssize_t decrypted_buffer_size;

1432

931

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1433

&decrypted_buffer, mc);

932

&decrypted_buffer);

1434

933

if(decrypted_buffer_size >= 0){

1435

934

1436

clearerr(stdout);

1437

935

written = 0;

1438

936

while(written < (size_t) decrypted_buffer_size){

1439

937

if(quit_now){

1455

953

}

1456

954

written += (size_t)ret;

1457

955

}

1458

ret = fflush(stdout);

1459

if(ret != 0){

1460

int e = errno;

1461

if(debug){

1462

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

1463

strerror(errno));

1464

}

1465

errno = e;

1466

goto mandos_end;

1467

}

1468

956

retval = 0;

1469

957

}

1470

958

}

1473

961

1474

962

mandos_end:

1475

963

{

1476

if(route_added){

1477

if(not delete_local_route(ip, if_index)){

1478

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

1479

" interface %d", ip, if_index);

1480

}

1481

}

1482

964

int e = errno;

1483

965

free(decrypted_buffer);

1484

966

free(buffer);

1485

967

if(tcp_sd >= 0){

1486

ret = close(tcp_sd);

968

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

1487

969

}

1488

970

if(ret == -1){

1489

971

if(e == 0){

1514

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1515

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1516

998

flags,

1517

void *mc){

1518

if(r == NULL){

1519

return;

1520

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1521

1001

1522

1002

/* Called whenever a service has been resolved successfully or

1523

1003

timed out */

1524

1004

1525

1005

if(quit_now){

1526

avahi_s_service_resolver_free(r);

1527

1006

return;

1528

1007

}

1529

1008

1533

1012

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

1534

1013

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

1535

1014

domain,

1536

avahi_strerror(avahi_server_errno

1537

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1538

1016

break;

1539

1017

1540

1018

case AVAHI_RESOLVER_FOUND:

1546

1024

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

1547

1025

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

1548

1026

}

1549

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

1550

interface,

1551

avahi_proto_to_af(proto),

1552

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1553

1029

if(ret == 0){

1554

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1555

1031

} else {

1556

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

1557

avahi_proto_to_af(proto),

1558

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

1559

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

1560

" list\n", name);

1561

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1562

1034

}

1563

1035

}

1564

1036

}

1574

1046

const char *domain,

1575

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1576

1048

flags,

1577

void *mc){

1578

if(b == NULL){

1579

return;

1580

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1581

1051

1582

1052

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

1583

1053

is removed from the LAN */

1591

1061

case AVAHI_BROWSER_FAILURE:

1592

1062

1593

1063

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

1594

avahi_strerror(avahi_server_errno

1595

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

1596

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1597

1066

return;

1598

1067

1599

1068

case AVAHI_BROWSER_NEW:

1602

1071

the callback function is called the Avahi server will free the

1603

1072

resolver for us. */

1604

1073

1605

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

1606

interface, protocol, name, type,

1607

domain, protocol, 0,

1608

resolve_callback, mc) == NULL)

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1609

1077

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

1610

1078

" %s\n", name,

1611

avahi_strerror(avahi_server_errno

1612

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1613

1080

break;

1614

1081

1615

1082

case AVAHI_BROWSER_REMOVE:

1634

1101

signal_received = sig;

1635

1102

int old_errno = errno;

1636

1103

/* set main loop to exit */

1637

if(simple_poll != NULL){

1638

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1639

1106

}

1640

1107

errno = old_errno;

1641

1108

}

1642

1109

1643

__attribute__((nonnull, warn_unused_result))

1644

1110

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

1645

1111

int ret;

1646

int old_errno;

1647

1112

1648

1113

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

1649

1114

if(s < 0){

1650

old_errno = errno;

1651

1115

perror_plus("socket");

1652

errno = old_errno;

1653

1116

return false;

1654

1117

}

1655

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

1656

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

1118

strcpy(ifr->ifr_name, ifname);

1657

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1658

1120

if(ret == -1){

1659

1121

if(debug){

1660

old_errno = errno;

1661

1122

perror_plus("ioctl SIOCGIFFLAGS");

1662

errno = old_errno;

1663

}

1664

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

1665

old_errno = errno;

1666

perror_plus("close");

1667

errno = old_errno;

1668

1123

}

1669

1124

return false;

1670

1125

}

1671

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

1672

old_errno = errno;

1673

perror_plus("close");

1674

errno = old_errno;

1675

}

1676

1126

return true;

1677

1127

}

1678

1128

1679

__attribute__((nonnull, warn_unused_result))

1680

1129

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

1681

1130

1682

1131

/* Reject the loopback device */

1724

1173

* corresponds to an acceptable network device.

1725

1174

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

1726

1175

*/

1727

__attribute__((nonnull, warn_unused_result))

1728

1176

int good_interface(const struct dirent *if_entry){

1729

1177

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

1730

1178

return 0;

1746

1194

}

1747

1195

1748

1196

/*

1749

* This function determines if a network interface is up.

1750

*/

1751

__attribute__((nonnull, warn_unused_result))

1752

bool interface_is_up(const char *interface){

1753

struct ifreq ifr;

1754

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

1755

if(debug){

1756

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

1757

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

1758

}

1759

return false;

1760

}

1761

1762

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

1763

}

1764

1765

/*

1766

* This function determines if a network interface is running

1767

*/

1768

__attribute__((nonnull, warn_unused_result))

1769

bool interface_is_running(const char *interface){

1770

struct ifreq ifr;

1771

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

1772

if(debug){

1773

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

1774

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

1775

}

1776

return false;

1777

}

1778

1779

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

1780

}

1781

1782

__attribute__((nonnull, pure, warn_unused_result))

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

1783

1239

int notdotentries(const struct dirent *direntry){

1784

1240

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

1785

1241

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

1792

1248

}

1793

1249

1794

1250

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

1795

__attribute__((nonnull, warn_unused_result))

1796

1251

int runnable_hook(const struct dirent *direntry){

1797

1252

int ret;

1798

1253

size_t sret;

1806

1261

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

1807

1262

"abcdefghijklmnopqrstuvwxyz"

1808

1263

"0123456789"

1809

"_.-");

1264

"_-");

1810

1265

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

1811

1266

/* Contains non-allowed characters */

1812

1267

if(debug){

1816

1271

return 0;

1817

1272

}

1818

1273

1819

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

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);

1820

1282

if(ret == -1){

1821

1283

if(debug){

1822

1284

perror_plus("Could not stat hook");

1846

1308

return 1;

1847

1309

}

1848

1310

1849

__attribute__((nonnull, warn_unused_result))

1850

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1851

mandos_context *mc){

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1852

1312

int ret;

1853

1313

struct timespec now;

1854

1314

struct timespec waited_time;

1855

1315

intmax_t block_time;

1856

1316

1857

1317

while(true){

1858

if(mc->current_server == NULL){

1859

if(debug){

1318

if(mc.current_server == NULL){

1319

if (debug){

1860

1320

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

1861

1321

" No timeout!\n");

1862

1322

}

1863

1323

ret = avahi_simple_poll_iterate(s, -1);

1864

1324

} else {

1865

if(debug){

1325

if (debug){

1866

1326

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

1867

1327

" it, or wait\n");

1868

1328

}

1875

1335

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

1876

1336

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

1877

1337

waited_time.tv_sec = (now.tv_sec

1878

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

1338

- mc.current_server->last_seen.tv_sec);

1879

1339

waited_time.tv_nsec = (now.tv_nsec

1880

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

1340

- mc.current_server->last_seen.tv_nsec);

1881

1341

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

1882

1342

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

1883

1343

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

1885

1345

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

1886

1346

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

1887

1347

1888

if(debug){

1348

if (debug){

1889

1349

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

1890

1350

block_time);

1891

1351

}

1892

1352

1893

1353

if(block_time <= 0){

1894

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

1895

mc->current_server->port,

1896

mc->current_server->if_index,

1897

mc->current_server->af, mc);

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);

1898

1358

if(ret == 0){

1899

avahi_simple_poll_quit(s);

1359

avahi_simple_poll_quit(mc.simple_poll);

1900

1360

return 0;

1901

1361

}

1902

1362

ret = clock_gettime(CLOCK_MONOTONIC,

1903

&mc->current_server->last_seen);

1363

&mc.current_server->last_seen);

1904

1364

if(ret == -1){

1905

1365

perror_plus("clock_gettime");

1906

1366

return -1;

1907

1367

}

1908

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

1368

mc.current_server = mc.current_server->next;

1909

1369

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

1910

1370

servers, but don't block */

1911

1371

}

1913

1373

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

1914

1374

}

1915

1375

if(ret != 0){

1916

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

1376

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

1917

1377

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

1918

1378

}

1919

1379

}

1920

1380

}

1921

1381

}

1922

1382

1923

__attribute__((nonnull))

1924

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

1383

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

1925

1384

const float delay){

1926

struct dirent **direntries = NULL;

1927

if(hookdir_fd == -1){

1928

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1929

| O_CLOEXEC);

1930

if(hookdir_fd == -1){

1931

if(errno == ENOENT){

1932

if(debug){

1933

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

1934

" found\n", hookdir);

1935

}

1936

} else {

1937

perror_plus("open");

1938

}

1939

return;

1940

}

1941

}

1942

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

1943

if(devnull == -1){

1944

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

1945

return;

1946

}

1947

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

1948

runnable_hook, alphasort);

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1949

1390

if(numhooks == -1){

1950

1391

perror_plus("scandir");

1951

close(devnull);

1952

return;

1953

}

1954

struct dirent *direntry;

1955

int ret;

1956

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

1957

direntry = direntries[i];

1958

if(debug){

1959

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

1960

direntry->d_name);

1961

}

1962

pid_t hook_pid = fork();

1963

if(hook_pid == 0){

1964

/* Child */

1965

/* Raise privileges */

1966

errno = raise_privileges_permanently();

1967

if(errno != 0){

1968

perror_plus("Failed to raise privileges");

1969

_exit(EX_NOPERM);

1970

}

1971

/* Set group */

1972

errno = 0;

1973

ret = setgid(0);

1974

if(ret == -1){

1975

perror_plus("setgid");

1976

_exit(EX_NOPERM);

1977

}

1978

/* Reset supplementary groups */

1979

errno = 0;

1980

ret = setgroups(0, NULL);

1981

if(ret == -1){

1982

perror_plus("setgroups");

1983

_exit(EX_NOPERM);

1984

}

1985

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

1986

if(ret == -1){

1987

perror_plus("setenv");

1988

_exit(EX_OSERR);

1989

}

1990

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

1991

if(ret == -1){

1992

perror_plus("setenv");

1993

_exit(EX_OSERR);

1994

}

1995

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

1996

if(ret == -1){

1997

perror_plus("setenv");

1998

_exit(EX_OSERR);

1999

}

2000

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

2001

if(ret == -1){

2002

perror_plus("setenv");

2003

_exit(EX_OSERR);

2004

}

2005

char *delaystring;

2006

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

2007

if(ret == -1){

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){

2008

1399

perror_plus("asprintf");

2009

_exit(EX_OSERR);

2010

}

2011

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

2012

if(ret == -1){

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

}

2013

1444

free(delaystring);

2014

perror_plus("setenv");

2015

_exit(EX_OSERR);

2016

}

2017

free(delaystring);

2018

if(connect_to != NULL){

2019

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

2020

if(ret == -1){

2021

perror_plus("setenv");

2022

_exit(EX_OSERR);

2023

}

2024

}

2025

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

2026

direntry->d_name,

2027

O_RDONLY));

2028

if(hook_fd == -1){

2029

perror_plus("openat");

2030

_exit(EXIT_FAILURE);

2031

}

2032

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

2033

perror_plus("close");

2034

_exit(EXIT_FAILURE);

2035

}

2036

ret = dup2(devnull, STDIN_FILENO);

2037

if(ret == -1){

2038

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

2039

_exit(EX_OSERR);

2040

}

2041

ret = close(devnull);

2042

if(ret == -1){

2043

perror_plus("close");

2044

_exit(EX_OSERR);

2045

}

2046

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2047

if(ret == -1){

2048

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

2049

_exit(EX_OSERR);

2050

}

2051

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

2052

environ) == -1){

2053

perror_plus("fexecve");

2054

_exit(EXIT_FAILURE);

2055

}

2056

} else {

2057

if(hook_pid == -1){

2058

perror_plus("fork");

2059

free(direntry);

2060

continue;

2061

}

2062

int status;

2063

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

2064

perror_plus("waitpid");

2065

free(direntry);

2066

continue;

2067

}

2068

if(WIFEXITED(status)){

2069

if(WEXITSTATUS(status) != 0){

2070

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

2071

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

2072

WEXITSTATUS(status));

2073

free(direntry);

2074

continue;

2075

}

2076

} else if(WIFSIGNALED(status)){

2077

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

2078

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

2079

WTERMSIG(status));

2080

free(direntry);

2081

continue;

2082

} else {

2083

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

2084

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

2085

free(direntry);

2086

continue;

2087

}

2088

}

2089

if(debug){

2090

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

2091

direntry->d_name);

2092

}

2093

free(direntry);

2094

}

2095

free(direntries);

2096

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

2097

perror_plus("close");

2098

} else {

2099

hookdir_fd = -1;

2100

}

2101

close(devnull);

2102

}

2103

2104

__attribute__((nonnull, warn_unused_result))

2105

int bring_up_interface(const char *const interface,

2106

const float delay){

2107

int old_errno = errno;

2108

int ret;

2109

struct ifreq network;

2110

unsigned int if_index = if_nametoindex(interface);

2111

if(if_index == 0){

2112

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

2113

errno = old_errno;

2114

return ENXIO;

2115

}

2116

2117

if(quit_now){

2118

errno = old_errno;

2119

return EINTR;

2120

}

2121

2122

if(not interface_is_up(interface)){

2123

int ret_errno = 0;

2124

int ioctl_errno = 0;

2125

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

2126

ret_errno = errno;

2127

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

2128

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

2129

errno = old_errno;

2130

return ret_errno;

2131

}

2132

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

2133

2134

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

2135

if(sd == -1){

2136

ret_errno = errno;

2137

perror_plus("socket");

2138

errno = old_errno;

2139

return ret_errno;

2140

}

2141

2142

if(quit_now){

2143

ret = close(sd);

2144

if(ret == -1){

2145

perror_plus("close");

2146

}

2147

errno = old_errno;

2148

return EINTR;

2149

}

2150

2151

if(debug){

2152

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

2153

interface);

2154

}

2155

2156

/* Raise privileges */

2157

ret_errno = raise_privileges();

2158

if(ret_errno != 0){

2159

errno = ret_errno;

2160

perror_plus("Failed to raise privileges");

2161

}

2162

2163

#ifdef __linux__

2164

int ret_linux;

2165

bool restore_loglevel = false;

2166

if(ret_errno == 0){

2167

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2168

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

2169

ret_linux = klogctl(8, NULL, 5);

2170

if(ret_linux == -1){

2171

perror_plus("klogctl");

2172

} else {

2173

restore_loglevel = true;

2174

}

2175

}

2176

#endif /* __linux__ */

2177

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

2178

ioctl_errno = errno;

2179

#ifdef __linux__

2180

if(restore_loglevel){

2181

ret_linux = klogctl(7, NULL, 0);

2182

if(ret_linux == -1){

2183

perror_plus("klogctl");

2184

}

2185

}

2186

#endif /* __linux__ */

2187

2188

/* If raise_privileges() succeeded above */

2189

if(ret_errno == 0){

2190

/* Lower privileges */

2191

ret_errno = lower_privileges();

2192

if(ret_errno != 0){

2193

errno = ret_errno;

2194

perror_plus("Failed to lower privileges");

2195

}

2196

}

2197

2198

/* Close the socket */

2199

ret = close(sd);

2200

if(ret == -1){

2201

perror_plus("close");

2202

}

2203

2204

if(ret_setflags == -1){

2205

errno = ioctl_errno;

2206

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2207

errno = old_errno;

2208

return ioctl_errno;

2209

}

2210

} else if(debug){

2211

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

2212

interface);

2213

}

2214

2215

/* Sleep checking until interface is running.

2216

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

2217

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

2218

if(interface_is_running(interface)){

2219

break;

2220

}

2221

struct timespec sleeptime = { .tv_nsec = 250000000 };

2222

ret = nanosleep(&sleeptime, NULL);

2223

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

2224

perror_plus("nanosleep");

2225

}

2226

}

2227

2228

errno = old_errno;

2229

return 0;

2230

}

2231

2232

__attribute__((nonnull, warn_unused_result))

2233

int take_down_interface(const char *const interface){

2234

int old_errno = errno;

2235

struct ifreq network;

2236

unsigned int if_index = if_nametoindex(interface);

2237

if(if_index == 0){

2238

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

2239

errno = old_errno;

2240

return ENXIO;

2241

}

2242

if(interface_is_up(interface)){

2243

int ret_errno = 0;

2244

int ioctl_errno = 0;

2245

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

2246

ret_errno = errno;

2247

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

2248

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

2249

errno = old_errno;

2250

return ret_errno;

2251

}

2252

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

2253

2254

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

2255

if(sd == -1){

2256

ret_errno = errno;

2257

perror_plus("socket");

2258

errno = old_errno;

2259

return ret_errno;

2260

}

2261

2262

if(debug){

2263

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

2264

interface);

2265

}

2266

2267

/* Raise privileges */

2268

ret_errno = raise_privileges();

2269

if(ret_errno != 0){

2270

errno = ret_errno;

2271

perror_plus("Failed to raise privileges");

2272

}

2273

2274

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

2275

ioctl_errno = errno;

2276

2277

/* If raise_privileges() succeeded above */

2278

if(ret_errno == 0){

2279

/* Lower privileges */

2280

ret_errno = lower_privileges();

2281

if(ret_errno != 0){

2282

errno = ret_errno;

2283

perror_plus("Failed to lower privileges");

2284

}

2285

}

2286

2287

/* Close the socket */

2288

int ret = close(sd);

2289

if(ret == -1){

2290

perror_plus("close");

2291

}

2292

2293

if(ret_setflags == -1){

2294

errno = ioctl_errno;

2295

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2296

errno = old_errno;

2297

return ioctl_errno;

2298

}

2299

} else if(debug){

2300

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

2301

interface);

2302

}

2303

2304

errno = old_errno;

2305

return 0;

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;

2306

1484

}

2307

1485

2308

1486

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

2309

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

2310

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

2311

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

2312

.current_server = NULL, .interfaces = NULL,

2313

.interfaces_size = 0 };

2314

1487

AvahiSServiceBrowser *sb = NULL;

2315

error_t ret_errno;

1488

int error;

2316

1489

int ret;

2317

1490

intmax_t tmpmax;

2318

1491

char *tmp;

2319

1492

int exitcode = EXIT_SUCCESS;

2320

char *interfaces_to_take_down = NULL;

2321

size_t interfaces_to_take_down_size = 0;

2322

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

2323

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

2324

char *tempdir = NULL;

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;

2325

1501

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2326

1502

const char *seckey = PATHDIR "/" SECKEY;

2327

1503

const char *pubkey = PATHDIR "/" PUBKEY;

2328

const char *dh_params_file = NULL;

2329

char *interfaces_hooks = NULL;

2330

1504

2331

1505

bool gnutls_initialized = false;

2332

1506

bool gpgme_initialized = false;

2384

1558

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

2385

1559

" Diffie-Hellman key exchange",

2386

1560

.group = 2 },

2387

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

2388

.arg = "FILE",

2389

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

2390

" for the Diffie-Hellman key exchange",

2391

.group = 2 },

2392

1561

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

2393

1562

.arg = "STRING",

2394

1563

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

2399

1568

.group = 2 },

2400

1569

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

2401

1570

.arg = "SECONDS",

2402

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

1571

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

2403

1572

.group = 2 },

2404

1573

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

2405

1574

.arg = "DIR",

2428

1597

connect_to = arg;

2429

1598

break;

2430

1599

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

2431

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

2432

arg, (int)',');

2433

if(ret_errno != 0){

2434

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

2435

}

1600

interface = arg;

2436

1601

break;

2437

1602

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

2438

1603

seckey = arg;

2449

1614

}

2450

1615

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

2451

1616

break;

2452

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

2453

dh_params_file = arg;

2454

break;

2455

1617

case 130: /* --priority */

2456

1618

mc.priority = arg;

2457

1619

break;

2484

1646

argp_state_help(state, state->out_stream,

2485

1647

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2486

1648

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

2487

1651

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

2488

1652

exit(argp_err_exit_status);

2489

1653

break;

2497

1661

.args_doc = "",

2498

1662

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

2499

1663

" passwords from a Mandos server" };

2500

ret_errno = argp_parse(&argp, argc, argv,

2501

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2502

switch(ret_errno){

1664

ret = argp_parse(&argp, argc, argv,

1665

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1666

switch(ret){

2503

1667

case 0:

2504

1668

break;

2505

1669

case ENOMEM:

2506

1670

default:

2507

errno = ret_errno;

1671

errno = ret;

2508

1672

perror_plus("argp_parse");

2509

1673

exitcode = EX_OSERR;

2510

1674

goto end;

2513

1677

goto end;

2514

1678

}

2515

1679

}

2516

2517

{

1680

1681

if(getuid() == 0){

2518

1682

/* Work around Debian bug #633582:

2519

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

2520

2521

/* Re-raise privileges */

2522

ret = raise_privileges();

2523

if(ret != 0){

2524

errno = ret;

2525

perror_plus("Failed to raise privileges");

2526

} else {

2527

struct stat st;

2528

2529

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

2530

int seckey_fd = open(seckey, O_RDONLY);

2531

if(seckey_fd == -1){

2532

perror_plus("open");

2533

} else {

2534

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

2535

if(ret == -1){

2536

perror_plus("fstat");

2537

} else {

2538

if(S_ISREG(st.st_mode)

2539

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

2540

ret = fchown(seckey_fd, uid, gid);

2541

if(ret == -1){

2542

perror_plus("fchown");

2543

}

2544

}

2545

}

2546

close(seckey_fd);

2547

}

2548

}

2549

2550

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

2551

int pubkey_fd = open(pubkey, O_RDONLY);

2552

if(pubkey_fd == -1){

2553

perror_plus("open");

2554

} else {

2555

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

2556

if(ret == -1){

2557

perror_plus("fstat");

2558

} else {

2559

if(S_ISREG(st.st_mode)

2560

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

2561

ret = fchown(pubkey_fd, uid, gid);

2562

if(ret == -1){

2563

perror_plus("fchown");

2564

}

2565

}

2566

}

2567

close(pubkey_fd);

2568

}

2569

}

2570

2571

if(dh_params_file != NULL

2572

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

2573

int dhparams_fd = open(dh_params_file, O_RDONLY);

2574

if(dhparams_fd == -1){

2575

perror_plus("open");

2576

} else {

2577

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

2578

if(ret == -1){

2579

perror_plus("fstat");

2580

} else {

2581

if(S_ISREG(st.st_mode)

2582

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

2583

ret = fchown(dhparams_fd, uid, gid);

2584

if(ret == -1){

2585

perror_plus("fchown");

2586

}

2587

}

2588

}

2589

close(dhparams_fd);

2590

}

2591

}

2592

2593

/* Lower privileges */

2594

ret = lower_privileges();

2595

if(ret != 0){

2596

errno = ret;

2597

perror_plus("Failed to lower privileges");

2598

}

2599

}

2600

}

2601

2602

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

2603

{

2604

char *interface = NULL;

2605

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

2606

interface))){

2607

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

2608

and if_nametoindex(interface) == 0){

2609

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

2610

fprintf_plus(stderr, "Not using nonexisting interface"

2611

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

2612

}

2613

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

2614

interface = NULL;

2615

}

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");

2616

1740

}

2617

1741

}

2618

1742

2619

1743

/* Run network hooks */

2620

1744

{

2621

if(mc.interfaces != NULL){

2622

interfaces_hooks = malloc(mc.interfaces_size);

2623

if(interfaces_hooks == NULL){

2624

perror_plus("malloc");

2625

goto end;

2626

}

2627

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

2628

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

2629

}

2630

run_network_hooks("start", interfaces_hooks != NULL ?

2631

interfaces_hooks : "", delay);

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

}

2632

1764

}

2633

1765

2634

1766

if(not debug){

2635

1767

avahi_set_log_function(empty_log);

2636

1768

}

2637

1769

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

2638

1802

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

2639

1803

from the signal handler */

2640

1804

/* Initialize the pseudo-RNG for Avahi */

2641

1805

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

2642

simple_poll = avahi_simple_poll_new();

2643

if(simple_poll == NULL){

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2644

1808

fprintf_plus(stderr,

2645

1809

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

2646

1810

exitcode = EX_UNAVAILABLE;

2710

1874

}

2711

1875

}

2712

1876

2713

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

2714

if(mc.interfaces == NULL){

2715

struct dirent **direntries = NULL;

2716

/* Look for any good interfaces */

2717

ret = scandir(sys_class_net, &direntries, good_interface,

2718

alphasort);

2719

if(ret >= 1){

2720

/* Add all found interfaces to interfaces list */

2721

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

2722

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

2723

direntries[i]->d_name);

2724

if(ret_errno != 0){

2725

errno = ret_errno;

2726

perror_plus("argz_add");

2727

free(direntries[i]);

2728

continue;

2729

}

2730

if(debug){

2731

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

2732

direntries[i]->d_name);

2733

}

2734

free(direntries[i]);

2735

}

2736

free(direntries);

2737

} else {

2738

if(ret == 0){

2739

free(direntries);

2740

}

2741

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

2742

exitcode = EXIT_FAILURE;

2743

goto end;

2744

}

2745

}

2746

2747

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

2748

{

2749

char *interface = NULL;

2750

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

2751

interface))){

2752

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

2753

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

2754

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

2755

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

2756

interface);

2757

interface = NULL;

2758

while((interface = argz_next(mc.interfaces,

2759

mc.interfaces_size, interface))){

2760

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

2761

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

2762

interface);

2763

interface = NULL;

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");

2764

1962

}

2765

1963

}

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){

2766

1981

break;

2767

1982

}

2768

bool interface_was_up = interface_is_up(interface);

2769

errno = bring_up_interface(interface, delay);

2770

if(not interface_was_up){

2771

if(errno != 0){

2772

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

2773

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

2774

} else {

2775

errno = argz_add(&interfaces_to_take_down,

2776

&interfaces_to_take_down_size,

2777

interface);

2778

if(errno != 0){

2779

perror_plus("argz_add");

2780

}

2781

}

2782

}

2783

}

2784

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

2785

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

2786

}

2787

}

2788

2789

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

2790

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

2791

if(debug){

2792

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

2793

mc.interfaces);

2794

}

2795

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

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

}

2796

2012

}

2797

2013

2798

2014

if(quit_now){

2799

2015

goto end;

2800

2016

}

2801

2017

2802

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

2018

ret = init_gnutls_global(pubkey, seckey);

2803

2019

if(ret == -1){

2804

2020

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

2805

2021

exitcode = EX_UNAVAILABLE;

2812

2028

goto end;

2813

2029

}

2814

2030

2815

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

2816

tempdir = mkdtemp(run_tempdir);

2817

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

2818

if(debug){

2819

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

2820

run_tempdir, old_tempdir);

2821

}

2822

tempdir = mkdtemp(old_tempdir);

2823

}

2824

if(tempdir == NULL){

2031

if(mkdtemp(tempdir) == NULL){

2825

2032

perror_plus("mkdtemp");

2826

2033

goto end;

2827

2034

}

2035

tempdir_created = true;

2828

2036

2829

2037

if(quit_now){

2830

2038

goto end;

2831

2039

}

2832

2040

2833

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

2041

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

2834

2042

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

2835

2043

exitcode = EX_UNAVAILABLE;

2836

2044

goto end;

2846

2054

/* Connect directly, do not use Zeroconf */

2847

2055

/* (Mainly meant for debugging) */

2848

2056

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

2849

2850

2057

if(address == NULL){

2851

2058

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

2852

2059

exitcode = EX_USAGE;

2857

2064

goto end;

2858

2065

}

2859

2066

2860

in_port_t port;

2067

uint16_t port;

2861

2068

errno = 0;

2862

2069

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

2863

2070

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

2864

or tmpmax != (in_port_t)tmpmax){

2071

or tmpmax != (uint16_t)tmpmax){

2865

2072

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

2866

2073

exitcode = EX_USAGE;

2867

2074

goto end;

2868

2075

}

2869

2076

2870

2077

if(quit_now){

2871

2078

goto end;

2872

2079

}

2873

2080

2874

port = (in_port_t)tmpmax;

2081

port = (uint16_t)tmpmax;

2875

2082

*address = '\0';

2876

2083

/* Colon in address indicates IPv6 */

2877

2084

int af;

2893

2100

}

2894

2101

2895

2102

while(not quit_now){

2896

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

2897

&mc);

2103

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

2898

2104

if(quit_now or ret == 0){

2899

2105

break;

2900

2106

}

2902

2108

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

2903

2109

(int)retry_interval);

2904

2110

}

2905

sleep((unsigned int)retry_interval);

2111

sleep((int)retry_interval);

2906

2112

}

2907

2113

2908

if(not quit_now){

2114

if (not quit_now){

2909

2115

exitcode = EXIT_SUCCESS;

2910

2116

}

2911

2117

2926

2132

config.publish_domain = 0;

2927

2133

2928

2134

/* Allocate a new server */

2929

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2930

&config, NULL, NULL, &ret);

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2931

2138

2932

2139

/* Free the Avahi configuration data */

2933

2140

avahi_server_config_free(&config);

2936

2143

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

2937

2144

if(mc.server == NULL){

2938

2145

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

2939

avahi_strerror(ret));

2146

avahi_strerror(error));

2940

2147

exitcode = EX_UNAVAILABLE;

2941

2148

goto end;

2942

2149

}

2948

2155

/* Create the Avahi service browser */

2949

2156

sb = avahi_s_service_browser_new(mc.server, if_index,

2950

2157

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2951

NULL, 0, browse_callback,

2952

(void *)&mc);

2158

NULL, 0, browse_callback, NULL);

2953

2159

if(sb == NULL){

2954

2160

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

2955

2161

avahi_strerror(avahi_server_errno(mc.server)));

2966

2172

if(debug){

2967

2173

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

2968

2174

}

2969

2970

ret = avahi_loop_with_timeout(simple_poll,

2971

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

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2972

2178

if(debug){

2973

2179

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

2974

2180

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

2977

2183

end:

2978

2184

2979

2185

if(debug){

2980

if(signal_received){

2981

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

2982

argv[0], signal_received,

2983

strsignal(signal_received));

2984

} else {

2985

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

2986

}

2186

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

2987

2187

}

2988

2188

2989

2189

/* Cleanup things */

2990

free(mc.interfaces);

2991

2992

2190

if(sb != NULL)

2993

2191

avahi_s_service_browser_free(sb);

2994

2192

2995

2193

if(mc.server != NULL)

2996

2194

avahi_server_free(mc.server);

2997

2195

2998

if(simple_poll != NULL)

2999

avahi_simple_poll_free(simple_poll);

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

3000

2198

3001

2199

if(gnutls_initialized){

3002

2200

gnutls_certificate_free_credentials(mc.cred);

2201

gnutls_global_deinit();

3003

2202

gnutls_dh_params_deinit(mc.dh_params);

3004

2203

}

3005

2204

3013

2212

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

3014

2213

while(mc.current_server != NULL){

3015

2214

server *next = mc.current_server->next;

3016

#ifdef __GNUC__

3017

#pragma GCC diagnostic push

3018

#pragma GCC diagnostic ignored "-Wcast-qual"

3019

#endif

3020

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

3021

#ifdef __GNUC__

3022

#pragma GCC diagnostic pop

3023

#endif

3024

2215

free(mc.current_server);

3025

2216

mc.current_server = next;

3026

2217

}

3027

2218

}

3028

2219

3029

/* Re-raise privileges */

2220

/* Re-raise priviliges */

3030

2221

{

3031

ret = raise_privileges();

3032

if(ret != 0){

3033

errno = ret;

3034

perror_plus("Failed to raise privileges");

3035

} else {

3036

3037

/* Run network hooks */

3038

run_network_hooks("stop", interfaces_hooks != NULL ?

3039

interfaces_hooks : "", delay);

3040

3041

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

3042

{

3043

char *interface = NULL;

3044

while((interface = argz_next(interfaces_to_take_down,

3045

interfaces_to_take_down_size,

3046

interface))){

3047

ret = take_down_interface(interface);

3048

if(ret != 0){

3049

errno = ret;

3050

perror_plus("Failed to take down interface");

3051

}

3052

}

3053

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

3054

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

3055

" down\n");

3056

}

3057

}

3058

}

3059

3060

ret = lower_privileges_permanently();

3061

if(ret != 0){

3062

errno = ret;

3063

perror_plus("Failed to lower privileges permanently");

3064

}

3065

}

3066

3067

free(interfaces_to_take_down);

3068

free(interfaces_hooks);

3069

3070

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

3071

uintmax_t level){

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

2227

}

2228

}

2229

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

}

2249

}

2250

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

2258

}

2259

2260

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

2261

if(tempdir_created){

3072

2262

struct dirent **direntries = NULL;

3073

int dret;

3074

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

3075

O_RDONLY

3076

| O_NOFOLLOW

3077

| O_DIRECTORY

3078

| O_PATH));

3079

if(dir_fd == -1){

3080

perror_plus("open");

3081

return;

3082

}

3083

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

3084

notdotentries, alphasort);

3085

if(numentries >= 0){

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

3086

2267

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

3087

if(debug){

3088

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

3089

dirname, direntries[i]->d_name);

3090

}

3091

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

3092

if(dret == -1){

3093

if(errno == EISDIR){

3094

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

3095

AT_REMOVEDIR);

3096

}

3097

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

3098

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

3099

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

3100

/* Recurse only in this special case */

3101

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

3102

dret = 0;

3103

}

3104

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

3105

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

3106

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

3107

}

3108

}

3109

free(direntries[i]);

3110

}

3111

3112

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

3113

free(direntries);

3114

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3115

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

3116

perror_plus("rmdir");

3117

}

3118

} else {

3119

perror_plus("scandirat");

3120

}

3121

close(dir_fd);

3122

}

3123

3124

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

3125

if(tempdir != NULL){

3126

clean_dir_at(-1, tempdir, 0);

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

}

3127

2294

}

3128

2295

3129

2296

if(quit_now){