/mandos/release : revision 237.7.142

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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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32

/* 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() */

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stdout, ferror(), remove() */

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

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

50

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

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asprintf(), strncpy(), strsignal()

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*/

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#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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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

62

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

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inet_pton(), connect() */

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

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

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61

*/

65

62

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

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63

strtoimax() */

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#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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program_invocation_short_name */

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67

#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(),

82

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

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unlinkat() */

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

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

77

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

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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,

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88

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

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89

WEXITSTATUS(), WTERMSIG() */

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90

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

98

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

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argz_delete(), argz_append(),

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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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105

92

#ifdef __linux__

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93

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

148

135

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

149

136

char *connect_to = NULL;

150

137

const char *hookdir = HOOKDIR;

151

int hookdir_fd = -1;

152

uid_t uid = 65534;

153

gid_t gid = 65534;

154

138

155

139

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

156

140

typedef struct server{

157

141

const char *ip;

158

in_port_t port;

142

uint16_t port;

159

143

AvahiIfIndex if_index;

160

144

int af;

161

145

struct timespec last_seen;

165

149

166

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

167

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

168

153

AvahiServer *server;

169

154

gnutls_certificate_credentials_t cred;

170

155

unsigned int dh_bits;

172

157

const char *priority;

173

158

gpgme_ctx_t ctx;

174

159

server *current_server;

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char *interfaces;

176

size_t interfaces_size;

177

160

} mandos_context;

178

161

179

/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

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

166

.current_server = NULL };

181

167

182

168

sig_atomic_t quit_now = 0;

183

169

int signal_received = 0;

191

177

perror(print_text);

192

178

}

193

179

194

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

180

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

195

181

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

196

182

va_list ap;

197

183

va_start (ap, format);

198

184

199

185

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

200

186

program_invocation_short_name));

201

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

187

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

202

188

}

203

189

204

190

/*

206

192

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

207

193

* "buffer_length" is how much is already used.

208

194

*/

209

__attribute__((nonnull, warn_unused_result))

210

195

size_t incbuffer(char **buffer, size_t buffer_length,

211

196

size_t buffer_capacity){

212

197

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;

198

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

199

if(buffer == NULL){

219

200

return 0;

220

201

}

221

*buffer = new_buf;

222

202

buffer_capacity += BUFFER_SIZE;

223

203

}

224

204

return buffer_capacity;

225

205

}

226

206

227

207

/* 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){

208

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

209

int af){

231

210

int ret;

232

211

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

233

212

if(new_server == NULL){

240

219

.af = af };

241

220

if(new_server->ip == NULL){

242

221

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

222

return false;

259

223

}

260

224

/* Special case of first server */

261

if(*current_server == NULL){

225

if (mc.current_server == NULL){

262

226

new_server->next = new_server;

263

227

new_server->prev = new_server;

264

*current_server = new_server;

228

mc.current_server = new_server;

229

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

265

230

} else {

266

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

267

new_server->next = *current_server;

268

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

231

new_server->next = mc.current_server;

232

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

269

233

new_server->prev->next = new_server;

270

(*current_server)->prev = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

271

240

}

272

241

return true;

273

242

}

275

244

/*

276

245

* Initialize GPGME.

277

246

*/

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){

247

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

248

const char *tempdir){

283

249

gpgme_error_t rc;

284

250

gpgme_engine_info_t engine_info;

285

251

252

286

253

/*

287

254

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

288

255

*/

289

bool import_key(const char * const filename){

256

bool import_key(const char *filename){

290

257

int ret;

291

258

int fd;

292

259

gpgme_data_t pgp_data;

304

271

return false;

305

272

}

306

273

307

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

274

rc = gpgme_op_import(mc.ctx, pgp_data);

308

275

if(rc != GPG_ERR_NO_ERROR){

309

276

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

310

277

gpgme_strsource(rc), gpgme_strerror(rc));

311

278

return false;

312

279

}

313

280

314

ret = close(fd);

281

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

315

282

if(ret == -1){

316

283

perror_plus("close");

317

284

}

354

321

}

355

322

356

323

/* Create new GPGME "context" */

357

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

324

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

358

325

if(rc != GPG_ERR_NO_ERROR){

359

326

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

360

327

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

373

340

* Decrypt OpenPGP data.

374

341

* Returns -1 on error

375

342

*/

376

__attribute__((nonnull, warn_unused_result))

377

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

378

344

size_t crypto_size,

379

char **plaintext,

380

mandos_context *mc){

345

char **plaintext){

381

346

gpgme_data_t dh_crypto, dh_plain;

382

347

gpgme_error_t rc;

383

348

ssize_t ret;

409

374

410

375

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

411

376

data buffer */

412

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

377

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

413

378

if(rc != GPG_ERR_NO_ERROR){

414

379

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

415

380

gpgme_strsource(rc), gpgme_strerror(rc));

416

381

plaintext_length = -1;

417

382

if(debug){

418

383

gpgme_decrypt_result_t result;

419

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

420

385

if(result == NULL){

421

386

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

422

387

} else {

499

464

return plaintext_length;

500

465

}

501

466

502

__attribute__((warn_unused_result, const))

503

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

504

if(str == NULL)

505

return "(unknown)";

506

return str;

507

}

508

509

__attribute__((warn_unused_result))

510

static const char *safer_gnutls_strerror(int value){

511

const char *ret = gnutls_strerror(value);

512

return safe_string(ret);

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

470

if(ret == NULL)

471

ret = "(unknown)";

472

return ret;

513

473

}

514

474

515

475

/* GnuTLS log function callback */

516

__attribute__((nonnull))

517

476

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

518

477

const char* string){

519

478

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

520

479

}

521

480

522

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

523

481

static int init_gnutls_global(const char *pubkeyfilename,

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

526

mandos_context *mc){

482

const char *seckeyfilename){

527

483

int ret;

528

unsigned int uret;

529

484

530

485

if(debug){

531

486

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

532

487

}

533

488

489

ret = gnutls_global_init();

490

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

493

return -1;

494

}

495

534

496

if(debug){

535

497

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

536

498

* - GnuTLS manual

540

502

}

541

503

542

504

/* OpenPGP credentials */

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

544

506

if(ret != GNUTLS_E_SUCCESS){

545

507

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

546

508

safer_gnutls_strerror(ret));

509

gnutls_global_deinit();

547

510

return -1;

548

511

}

549

512

555

518

}

556

519

557

520

ret = gnutls_certificate_set_openpgp_key_file

558

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

559

522

GNUTLS_OPENPGP_FMT_BASE64);

560

523

if(ret != GNUTLS_E_SUCCESS){

561

524

fprintf_plus(stderr,

567

530

}

568

531

569

532

/* GnuTLS server initialization */

570

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

571

534

if(ret != GNUTLS_E_SUCCESS){

572

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

573

536

" initialization: %s\n",

574

537

safer_gnutls_strerror(ret));

575

538

goto globalfail;

576

539

}

577

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

578

if(dhparamsfilename != NULL){

579

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

580

do {

581

int dhpfile = open(dhparamsfilename, O_RDONLY);

582

if(dhpfile == -1){

583

perror_plus("open");

584

dhparamsfilename = NULL;

585

break;

586

}

587

size_t params_capacity = 0;

588

while(true){

589

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

590

(size_t)params.size,

591

(size_t)params_capacity);

592

if(params_capacity == 0){

593

perror_plus("incbuffer");

594

free(params.data);

595

params.data = NULL;

596

dhparamsfilename = NULL;

597

break;

598

}

599

ssize_t bytes_read = read(dhpfile,

600

params.data + params.size,

601

BUFFER_SIZE);

602

/* EOF */

603

if(bytes_read == 0){

604

break;

605

}

606

/* check bytes_read for failure */

607

if(bytes_read < 0){

608

perror_plus("read");

609

free(params.data);

610

params.data = NULL;

611

dhparamsfilename = NULL;

612

break;

613

}

614

params.size += (unsigned int)bytes_read;

615

}

616

if(params.data == NULL){

617

dhparamsfilename = NULL;

618

}

619

if(dhparamsfilename == NULL){

620

break;

621

}

622

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

623

GNUTLS_X509_FMT_PEM);

624

if(ret != GNUTLS_E_SUCCESS){

625

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

626

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

627

safer_gnutls_strerror(ret));

628

dhparamsfilename = NULL;

629

}

630

free(params.data);

631

} while(false);

632

}

633

if(dhparamsfilename == NULL){

634

if(mc->dh_bits == 0){

635

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

636

/* Try to read the private key file */

637

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

638

do {

639

int secfile = open(seckeyfilename, O_RDONLY);

640

if(secfile == -1){

641

perror_plus("open");

642

break;

643

}

644

size_t buffer_capacity = 0;

645

while(true){

646

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

647

(size_t)buffer.size,

648

(size_t)buffer_capacity);

649

if(buffer_capacity == 0){

650

perror_plus("incbuffer");

651

free(buffer.data);

652

buffer.data = NULL;

653

break;

654

}

655

ssize_t bytes_read = read(secfile,

656

buffer.data + buffer.size,

657

BUFFER_SIZE);

658

/* EOF */

659

if(bytes_read == 0){

660

break;

661

}

662

/* check bytes_read for failure */

663

if(bytes_read < 0){

664

perror_plus("read");

665

free(buffer.data);

666

buffer.data = NULL;

667

break;

668

}

669

buffer.size += (unsigned int)bytes_read;

670

}

671

close(secfile);

672

} while(false);

673

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

674

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

675

if(buffer.data != NULL){

676

{

677

gnutls_openpgp_privkey_t privkey = NULL;

678

ret = gnutls_openpgp_privkey_init(&privkey);

679

if(ret != GNUTLS_E_SUCCESS){

680

fprintf_plus(stderr, "Error initializing OpenPGP key"

681

" structure: %s",

682

safer_gnutls_strerror(ret));

683

free(buffer.data);

684

buffer.data = NULL;

685

} else {

686

ret = gnutls_openpgp_privkey_import

687

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

688

if(ret != GNUTLS_E_SUCCESS){

689

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

690

safer_gnutls_strerror(ret));

691

privkey = NULL;

692

}

693

free(buffer.data);

694

buffer.data = NULL;

695

if(privkey != NULL){

696

/* Use private key to suggest an appropriate

697

sec_param */

698

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

699

gnutls_openpgp_privkey_deinit(privkey);

700

if(debug){

701

fprintf_plus(stderr, "This OpenPGP key implies using"

702

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

703

safe_string(gnutls_sec_param_get_name

704

(sec_param)));

705

}

706

}

707

}

708

}

709

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

710

/* Err on the side of caution */

711

sec_param = GNUTLS_SEC_PARAM_ULTRA;

712

if(debug){

713

fprintf_plus(stderr, "Falling back to security parameter"

714

" \"%s\"\n",

715

safe_string(gnutls_sec_param_get_name

716

(sec_param)));

717

}

718

}

719

}

720

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

721

if(uret != 0){

722

mc->dh_bits = uret;

723

if(debug){

724

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

725

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

726

safe_string(gnutls_sec_param_get_name

727

(sec_param)),

728

mc->dh_bits);

729

}

730

} else {

731

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

732

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

733

safe_string(gnutls_sec_param_get_name

734

(sec_param)),

735

safer_gnutls_strerror(ret));

736

goto globalfail;

737

}

738

} else if(debug){

739

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

740

mc->dh_bits);

741

}

742

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

743

if(ret != GNUTLS_E_SUCCESS){

744

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

745

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

746

safer_gnutls_strerror(ret));

747

goto globalfail;

748

}

749

}

750

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

540

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

541

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

544

goto globalfail;

545

}

546

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

751

548

752

549

return 0;

753

550

754

551

globalfail:

755

552

756

gnutls_certificate_free_credentials(mc->cred);

757

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_certificate_free_credentials(mc.cred);

554

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

758

556

return -1;

759

557

}

760

558

761

__attribute__((nonnull, warn_unused_result))

762

static int init_gnutls_session(gnutls_session_t *session,

763

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

764

560

int ret;

765

561

/* GnuTLS session creation */

766

562

do {

778

574

{

779

575

const char *err;

780

576

do {

781

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

577

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

782

578

if(quit_now){

783

579

gnutls_deinit(*session);

784

580

return -1;

795

591

796

592

do {

797

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

798

mc->cred);

594

mc.cred);

799

595

if(quit_now){

800

596

gnutls_deinit(*session);

801

597

return -1;

811

607

/* ignore client certificate if any. */

812

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

813

609

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

611

814

612

return 0;

815

613

}

816

614

818

616

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

819

617

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

820

618

821

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

822

__attribute__((warn_unused_result))

823

int raise_privileges(void){

824

int old_errno = errno;

825

int ret = 0;

826

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

827

ret = errno;

828

}

829

errno = old_errno;

830

return ret;

831

}

832

833

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

834

__attribute__((warn_unused_result))

835

int raise_privileges_permanently(void){

836

int old_errno = errno;

837

int ret = raise_privileges();

838

if(ret != 0){

839

errno = old_errno;

840

return ret;

841

}

842

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

843

ret = errno;

844

}

845

errno = old_errno;

846

return ret;

847

}

848

849

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

850

__attribute__((warn_unused_result))

851

int lower_privileges(void){

852

int old_errno = errno;

853

int ret = 0;

854

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

855

ret = errno;

856

}

857

errno = old_errno;

858

return ret;

859

}

860

861

/* Lower privileges permanently */

862

__attribute__((warn_unused_result))

863

int lower_privileges_permanently(void){

864

int old_errno = errno;

865

int ret = 0;

866

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

867

ret = errno;

868

}

869

errno = old_errno;

870

return ret;

871

}

872

873

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

874

__attribute__((nonnull, warn_unused_result))

875

static bool add_delete_local_route(const bool add,

876

const char *address,

877

AvahiIfIndex if_index){

878

int ret;

879

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

880

char add_arg[] = "add";

881

char delete_arg[] = "delete";

882

char debug_flag[] = "--debug";

883

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

884

if(pluginhelperdir == NULL){

885

if(debug){

886

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

887

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

888

}

889

return false;

890

}

891

892

char interface[IF_NAMESIZE];

893

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

894

perror_plus("if_indextoname");

895

return false;

896

}

897

898

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

899

if(devnull == -1){

900

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

901

return false;

902

}

903

pid_t pid = fork();

904

if(pid == 0){

905

/* Child */

906

/* Raise privileges */

907

errno = raise_privileges_permanently();

908

if(errno != 0){

909

perror_plus("Failed to raise privileges");

910

/* _exit(EX_NOPERM); */

911

} else {

912

/* Set group */

913

errno = 0;

914

ret = setgid(0);

915

if(ret == -1){

916

perror_plus("setgid");

917

_exit(EX_NOPERM);

918

}

919

/* Reset supplementary groups */

920

errno = 0;

921

ret = setgroups(0, NULL);

922

if(ret == -1){

923

perror_plus("setgroups");

924

_exit(EX_NOPERM);

925

}

926

}

927

ret = dup2(devnull, STDIN_FILENO);

928

if(ret == -1){

929

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

930

_exit(EX_OSERR);

931

}

932

ret = close(devnull);

933

if(ret == -1){

934

perror_plus("close");

935

_exit(EX_OSERR);

936

}

937

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

938

if(ret == -1){

939

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

940

_exit(EX_OSERR);

941

}

942

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

943

O_RDONLY

944

| O_DIRECTORY

945

| O_PATH

946

| O_CLOEXEC));

947

if(helperdir_fd == -1){

948

perror_plus("open");

949

_exit(EX_UNAVAILABLE);

950

}

951

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

952

helper, O_RDONLY));

953

if(helper_fd == -1){

954

perror_plus("openat");

955

close(helperdir_fd);

956

_exit(EX_UNAVAILABLE);

957

}

958

close(helperdir_fd);

959

#ifdef __GNUC__

960

#pragma GCC diagnostic push

961

#pragma GCC diagnostic ignored "-Wcast-qual"

962

#endif

963

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

964

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

965

interface, debug ? debug_flag : NULL, NULL },

966

environ) == -1){

967

#ifdef __GNUC__

968

#pragma GCC diagnostic pop

969

#endif

970

perror_plus("fexecve");

971

_exit(EXIT_FAILURE);

972

}

973

}

974

if(pid == -1){

975

perror_plus("fork");

976

return false;

977

}

978

int status;

979

pid_t pret = -1;

980

errno = 0;

981

do {

982

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

983

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

984

int errno_raising = 0;

985

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

986

errno_raising = errno;

987

perror_plus("Failed to raise privileges in order to"

988

" kill helper program");

989

}

990

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

991

perror_plus("kill");

992

}

993

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

994

perror_plus("Failed to lower privileges after killing"

995

" helper program");

996

}

997

return false;

998

}

999

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

1000

if(pret == -1){

1001

perror_plus("waitpid");

1002

return false;

1003

}

1004

if(WIFEXITED(status)){

1005

if(WEXITSTATUS(status) != 0){

1006

fprintf_plus(stderr, "Error: iprouteadddel exited"

1007

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

1008

return false;

1009

}

1010

return true;

1011

}

1012

if(WIFSIGNALED(status)){

1013

fprintf_plus(stderr, "Error: iprouteadddel died by"

1014

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

1015

return false;

1016

}

1017

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

1018

return false;

1019

}

1020

1021

__attribute__((nonnull, warn_unused_result))

1022

static bool add_local_route(const char *address,

1023

AvahiIfIndex if_index){

1024

if(debug){

1025

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

1026

}

1027

return add_delete_local_route(true, address, if_index);

1028

}

1029

1030

__attribute__((nonnull, warn_unused_result))

1031

static bool delete_local_route(const char *address,

1032

AvahiIfIndex if_index){

1033

if(debug){

1034

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

1035

}

1036

return add_delete_local_route(false, address, if_index);

1037

}

1038

1039

619

/* Called when a Mandos server is found */

1040

__attribute__((nonnull, warn_unused_result))

1041

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

620

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

1042

621

AvahiIfIndex if_index,

1043

int af, mandos_context *mc){

622

int af){

1044

623

int ret, tcp_sd = -1;

1045

624

ssize_t sret;

1046

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

1047

629

char *buffer = NULL;

1048

630

char *decrypted_buffer = NULL;

1049

631

size_t buffer_length = 0;

1052

634

int retval = -1;

1053

635

gnutls_session_t session;

1054

636

int pf; /* Protocol family */

1055

bool route_added = false;

1056

637

1057

638

errno = 0;

1058

639

1074

655

return -1;

1075

656

}

1076

657

1077

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

1078

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

1079

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

1080

bool match = false;

1081

{

1082

char *interface = NULL;

1083

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

1084

mc->interfaces_size,

1085

interface))){

1086

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

1087

match = true;

1088

break;

1089

}

1090

}

1091

}

1092

if(not match){

1093

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

1094

connect to the server */

1095

if(debug){

1096

char interface[IF_NAMESIZE];

1097

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

1098

perror_plus("if_indextoname");

1099

} else {

1100

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

1101

" \"%s\"\n",

1102

if_indextoname((unsigned int)if_index,

1103

interface));

1104

}

1105

}

1106

return -1;

1107

}

1108

}

1109

1110

ret = init_gnutls_session(&session, mc);

658

ret = init_gnutls_session(&session);

1111

659

if(ret != 0){

1112

660

return -1;

1113

661

}

1114

662

1115

663

if(debug){

1116

664

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

1117

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

665

PRIu16 "\n", ip, port);

1118

666

}

1119

667

1120

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

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

1121

669

if(tcp_sd < 0){

1122

670

int e = errno;

1123

671

perror_plus("socket");

1130

678

goto mandos_end;

1131

679

}

1132

680

681

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

1133

682

if(af == AF_INET6){

1134

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

1135

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

1136

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

683

to.in6.sin6_family = (sa_family_t)af;

684

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

1137

685

} else { /* IPv4 */

1138

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

1139

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

1140

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

686

to.in.sin_family = (sa_family_t)af;

687

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

1141

688

}

1142

689

if(ret < 0 ){

1143

690

int e = errno;

1152

699

goto mandos_end;

1153

700

}

1154

701

if(af == AF_INET6){

1155

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

1156

if(IN6_IS_ADDR_LINKLOCAL

1157

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

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

1158

709

if(if_index == AVAHI_IF_UNSPEC){

1159

710

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

1160

711

" incomplete without a network interface\n");

1162

713

goto mandos_end;

1163

714

}

1164

715

/* Set the network interface number as scope */

1165

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

1166

717

}

1167

718

} else {

1168

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

1169

722

}

1170

723

1171

724

if(quit_now){

1179

732

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

1180

733

perror_plus("if_indextoname");

1181

734

} else {

1182

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

1183

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

735

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

736

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

1184

737

}

1185

738

} else {

1186

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

1187

ip, (uintmax_t)port);

739

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

740

ip, port);

1188

741

}

1189

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1190

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1191

if(af == AF_INET6){

1192

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

1193

sizeof(struct sockaddr_in6),

1194

addrstr, sizeof(addrstr), NULL, 0,

1195

NI_NUMERICHOST);

1196

} else {

1197

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

1198

sizeof(struct sockaddr_in),

1199

addrstr, sizeof(addrstr), NULL, 0,

1200

NI_NUMERICHOST);

1201

}

1202

if(ret == EAI_SYSTEM){

1203

perror_plus("getnameinfo");

1204

} else if(ret != 0) {

1205

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

1206

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

1207

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

1208

}

1209

}

1210

1211

if(quit_now){

1212

errno = EINTR;

1213

goto mandos_end;

1214

}

1215

1216

while(true){

1217

if(af == AF_INET6){

1218

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

1219

sizeof(struct sockaddr_in6));

1220

} else {

1221

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

1222

sizeof(struct sockaddr_in));

1223

}

1224

if(ret < 0){

1225

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

1226

and if_index != AVAHI_IF_UNSPEC

1227

and connect_to == NULL

1228

and not route_added and

1229

((af == AF_INET6 and not

1230

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1231

&to)->sin6_addr)))

1232

or (af == AF_INET and

1233

/* Not a a IPv4LL address */

1234

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

1235

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

1236

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

1237

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

1238

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

1239

connect to a Mandos server announced by Avahi on a server

1240

host with a global address. Work around this by retrying

1241

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

1242

1243

Avahi bug reference:

1244

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

1245

https://bugs.debian.org/587961

1246

*/

1247

if(debug){

1248

fprintf_plus(stderr, "Mandos server unreachable, trying"

1249

" direct route\n");

1250

}

1251

int e = errno;

1252

route_added = add_local_route(ip, if_index);

1253

if(route_added){

1254

continue;

1255

}

1256

errno = e;

1257

}

1258

if(errno != ECONNREFUSED or debug){

1259

int e = errno;

1260

perror_plus("connect");

1261

errno = e;

1262

}

1263

goto mandos_end;

1264

}

1265

1266

if(quit_now){

1267

errno = EINTR;

1268

goto mandos_end;

1269

}

1270

break;

744

const char *pcret;

745

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

748

} else {

749

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

750

sizeof(addrstr));

751

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

758

}

759

}

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

if(af == AF_INET6){

767

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

768

} else {

769

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

770

}

771

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

1271

783

}

1272

784

1273

785

const char *out = mandos_protocol_version;

1424

936

if(buffer_length > 0){

1425

937

ssize_t decrypted_buffer_size;

1426

938

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1427

&decrypted_buffer, mc);

939

&decrypted_buffer);

1428

940

if(decrypted_buffer_size >= 0){

1429

941

1430

clearerr(stdout);

1431

942

written = 0;

1432

943

while(written < (size_t) decrypted_buffer_size){

1433

944

if(quit_now){

1449

960

}

1450

961

written += (size_t)ret;

1451

962

}

1452

ret = fflush(stdout);

1453

if(ret != 0){

1454

int e = errno;

1455

if(debug){

1456

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

1457

strerror(errno));

1458

}

1459

errno = e;

1460

goto mandos_end;

1461

}

1462

963

retval = 0;

1463

964

}

1464

965

}

1467

968

1468

969

mandos_end:

1469

970

{

1470

if(route_added){

1471

if(not delete_local_route(ip, if_index)){

1472

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

1473

" interface %d", ip, if_index);

1474

}

1475

}

1476

971

int e = errno;

1477

972

free(decrypted_buffer);

1478

973

free(buffer);

1479

974

if(tcp_sd >= 0){

1480

ret = close(tcp_sd);

975

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

1481

976

}

1482

977

if(ret == -1){

1483

978

if(e == 0){

1508

1003

AVAHI_GCC_UNUSED AvahiStringList *txt,

1509

1004

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1510

1005

flags,

1511

void *mc){

1512

if(r == NULL){

1513

return;

1514

}

1006

AVAHI_GCC_UNUSED void* userdata){

1007

assert(r);

1515

1008

1516

1009

/* Called whenever a service has been resolved successfully or

1517

1010

timed out */

1518

1011

1519

1012

if(quit_now){

1520

avahi_s_service_resolver_free(r);

1521

1013

return;

1522

1014

}

1523

1015

1527

1019

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

1528

1020

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

1529

1021

domain,

1530

avahi_strerror(avahi_server_errno

1531

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

1022

avahi_strerror(avahi_server_errno(mc.server)));

1532

1023

break;

1533

1024

1534

1025

case AVAHI_RESOLVER_FOUND:

1540

1031

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

1541

1032

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

1542

1033

}

1543

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

1544

interface,

1545

avahi_proto_to_af(proto),

1546

mc);

1034

int ret = start_mandos_communication(ip, port, interface,

1035

avahi_proto_to_af(proto));

1547

1036

if(ret == 0){

1548

avahi_simple_poll_quit(simple_poll);

1037

avahi_simple_poll_quit(mc.simple_poll);

1549

1038

} else {

1550

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

1551

avahi_proto_to_af(proto),

1552

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

1039

if(not add_server(ip, port, interface,

1040

avahi_proto_to_af(proto))){

1553

1041

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

1554

1042

" list\n", name);

1555

1043

}

1568

1056

const char *domain,

1569

1057

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1570

1058

flags,

1571

void *mc){

1572

if(b == NULL){

1573

return;

1574

}

1059

AVAHI_GCC_UNUSED void* userdata){

1060

assert(b);

1575

1061

1576

1062

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

1577

1063

is removed from the LAN */

1585

1071

case AVAHI_BROWSER_FAILURE:

1586

1072

1587

1073

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

1588

avahi_strerror(avahi_server_errno

1589

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

1590

avahi_simple_poll_quit(simple_poll);

1074

avahi_strerror(avahi_server_errno(mc.server)));

1075

avahi_simple_poll_quit(mc.simple_poll);

1591

1076

return;

1592

1077

1593

1078

case AVAHI_BROWSER_NEW:

1596

1081

the callback function is called the Avahi server will free the

1597

1082

resolver for us. */

1598

1083

1599

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

1600

interface, protocol, name, type,

1601

domain, protocol, 0,

1602

resolve_callback, mc) == NULL)

1084

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

1085

name, type, domain, protocol, 0,

1086

resolve_callback, NULL) == NULL)

1603

1087

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

1604

1088

" %s\n", name,

1605

avahi_strerror(avahi_server_errno

1606

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

1089

avahi_strerror(avahi_server_errno(mc.server)));

1607

1090

break;

1608

1091

1609

1092

case AVAHI_BROWSER_REMOVE:

1628

1111

signal_received = sig;

1629

1112

int old_errno = errno;

1630

1113

/* set main loop to exit */

1631

if(simple_poll != NULL){

1632

avahi_simple_poll_quit(simple_poll);

1114

if(mc.simple_poll != NULL){

1115

avahi_simple_poll_quit(mc.simple_poll);

1633

1116

}

1634

1117

errno = old_errno;

1635

1118

}

1636

1119

1637

__attribute__((nonnull, warn_unused_result))

1638

1120

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

1639

1121

int ret;

1640

int old_errno;

1641

1122

1642

1123

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

1643

1124

if(s < 0){

1644

old_errno = errno;

1645

1125

perror_plus("socket");

1646

errno = old_errno;

1647

1126

return false;

1648

1127

}

1649

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

1650

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

1128

strcpy(ifr->ifr_name, ifname);

1651

1129

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1652

1130

if(ret == -1){

1653

1131

if(debug){

1654

old_errno = errno;

1655

1132

perror_plus("ioctl SIOCGIFFLAGS");

1656

errno = old_errno;

1657

1133

}

1658

1134

return false;

1659

1135

}

1660

1136

return true;

1661

1137

}

1662

1138

1663

__attribute__((nonnull, warn_unused_result))

1664

1139

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

1665

1140

1666

1141

/* Reject the loopback device */

1708

1183

* corresponds to an acceptable network device.

1709

1184

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

1710

1185

*/

1711

__attribute__((nonnull, warn_unused_result))

1712

1186

int good_interface(const struct dirent *if_entry){

1713

1187

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

1714

1188

return 0;

1730

1204

}

1731

1205

1732

1206

/*

1733

* This function determines if a network interface is up.

1734

*/

1735

__attribute__((nonnull, warn_unused_result))

1736

bool interface_is_up(const char *interface){

1737

struct ifreq ifr;

1738

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

1739

if(debug){

1740

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

1741

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

1742

}

1743

return false;

1744

}

1745

1746

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

1747

}

1748

1749

/*

1750

* This function determines if a network interface is running

1751

*/

1752

__attribute__((nonnull, warn_unused_result))

1753

bool interface_is_running(const char *interface){

1754

struct ifreq ifr;

1755

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

1756

if(debug){

1757

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

1758

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

1759

}

1760

return false;

1761

}

1762

1763

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

1764

}

1765

1766

__attribute__((nonnull, pure, warn_unused_result))

1207

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

1208

* corresponds to an acceptable network device which is up.

1209

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

1210

*/

1211

int up_interface(const struct dirent *if_entry){

1212

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

1213

return 0;

1214

}

1215

1216

struct ifreq ifr;

1217

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

1218

if(debug){

1219

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

1220

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

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject down interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

/* Reject non-running interfaces */

1235

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

1236

if(debug){

1237

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

1238

if_entry->d_name);

1239

}

1240

return 0;

1241

}

1242

1243

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

1244

return 0;

1245

}

1246

return 1;

1247

}

1248

1767

1249

int notdotentries(const struct dirent *direntry){

1768

1250

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

1769

1251

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

1776

1258

}

1777

1259

1778

1260

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

1779

__attribute__((nonnull, warn_unused_result))

1780

1261

int runnable_hook(const struct dirent *direntry){

1781

1262

int ret;

1782

1263

size_t sret;

1790

1271

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

1791

1272

"abcdefghijklmnopqrstuvwxyz"

1792

1273

"0123456789"

1793

"_.-");

1274

"_-");

1794

1275

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

1795

1276

/* Contains non-allowed characters */

1796

1277

if(debug){

1800

1281

return 0;

1801

1282

}

1802

1283

1803

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

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1804

1292

if(ret == -1){

1805

1293

if(debug){

1806

1294

perror_plus("Could not stat hook");

1830

1318

return 1;

1831

1319

}

1832

1320

1833

__attribute__((nonnull, warn_unused_result))

1834

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1835

mandos_context *mc){

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1836

1322

int ret;

1837

1323

struct timespec now;

1838

1324

struct timespec waited_time;

1839

1325

intmax_t block_time;

1840

1326

1841

1327

while(true){

1842

if(mc->current_server == NULL){

1843

if(debug){

1328

if(mc.current_server == NULL){

1329

if (debug){

1844

1330

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

1845

1331

" No timeout!\n");

1846

1332

}

1847

1333

ret = avahi_simple_poll_iterate(s, -1);

1848

1334

} else {

1849

if(debug){

1335

if (debug){

1850

1336

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

1851

1337

" it, or wait\n");

1852

1338

}

1859

1345

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

1860

1346

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

1861

1347

waited_time.tv_sec = (now.tv_sec

1862

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

1348

- mc.current_server->last_seen.tv_sec);

1863

1349

waited_time.tv_nsec = (now.tv_nsec

1864

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

1350

- mc.current_server->last_seen.tv_nsec);

1865

1351

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

1866

1352

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

1867

1353

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

1869

1355

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

1870

1356

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

1871

1357

1872

if(debug){

1358

if (debug){

1873

1359

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

1874

1360

block_time);

1875

1361

}

1876

1362

1877

1363

if(block_time <= 0){

1878

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

1879

mc->current_server->port,

1880

mc->current_server->if_index,

1881

mc->current_server->af, mc);

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1882

1368

if(ret == 0){

1883

avahi_simple_poll_quit(s);

1369

avahi_simple_poll_quit(mc.simple_poll);

1884

1370

return 0;

1885

1371

}

1886

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1887

&mc->current_server->last_seen);

1373

&mc.current_server->last_seen);

1888

1374

if(ret == -1){

1889

1375

perror_plus("clock_gettime");

1890

1376

return -1;

1891

1377

}

1892

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

1378

mc.current_server = mc.current_server->next;

1893

1379

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

1894

1380

servers, but don't block */

1895

1381

}

1897

1383

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

1898

1384

}

1899

1385

if(ret != 0){

1900

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

1386

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

1901

1387

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

1902

1388

}

1903

1389

}

1904

1390

}

1905

1391

}

1906

1392

1907

__attribute__((nonnull))

1908

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

1393

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

1909

1394

const float delay){

1910

struct dirent **direntries = NULL;

1911

if(hookdir_fd == -1){

1912

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1913

| O_CLOEXEC);

1914

if(hookdir_fd == -1){

1915

if(errno == ENOENT){

1916

if(debug){

1917

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

1918

" found\n", hookdir);

1919

}

1920

} else {

1921

perror_plus("open");

1922

}

1923

return;

1924

}

1925

}

1926

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

1927

runnable_hook, alphasort);

1395

struct dirent **direntries;

1396

struct dirent *direntry;

1397

int ret;

1398

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

1399

alphasort);

1928

1400

if(numhooks == -1){

1929

1401

perror_plus("scandir");

1930

return;

1931

}

1932

struct dirent *direntry;

1933

int ret;

1934

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

1935

if(devnull == -1){

1936

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

1937

return;

1938

}

1939

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

1940

direntry = direntries[i];

1941

if(debug){

1942

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

1943

direntry->d_name);

1944

}

1945

pid_t hook_pid = fork();

1946

if(hook_pid == 0){

1947

/* Child */

1948

/* Raise privileges */

1949

errno = raise_privileges_permanently();

1950

if(errno != 0){

1951

perror_plus("Failed to raise privileges");

1952

_exit(EX_NOPERM);

1953

}

1954

/* Set group */

1955

errno = 0;

1956

ret = setgid(0);

1957

if(ret == -1){

1958

perror_plus("setgid");

1959

_exit(EX_NOPERM);

1960

}

1961

/* Reset supplementary groups */

1962

errno = 0;

1963

ret = setgroups(0, NULL);

1964

if(ret == -1){

1965

perror_plus("setgroups");

1966

_exit(EX_NOPERM);

1967

}

1968

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

1969

if(ret == -1){

1970

perror_plus("setenv");

1971

_exit(EX_OSERR);

1972

}

1973

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

1974

if(ret == -1){

1975

perror_plus("setenv");

1976

_exit(EX_OSERR);

1977

}

1978

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

1979

if(ret == -1){

1980

perror_plus("setenv");

1981

_exit(EX_OSERR);

1982

}

1983

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

1984

if(ret == -1){

1985

perror_plus("setenv");

1986

_exit(EX_OSERR);

1987

}

1988

char *delaystring;

1989

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

1990

if(ret == -1){

1402

} else {

1403

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

1404

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

1405

direntry = direntries[i];

1406

char *fullname = NULL;

1407

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

1408

if(ret < 0){

1991

1409

perror_plus("asprintf");

1992

_exit(EX_OSERR);

1993

}

1994

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

1995

if(ret == -1){

1410

continue;

1411

}

1412

if(debug){

1413

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

1414

direntry->d_name);

1415

}

1416

pid_t hook_pid = fork();

1417

if(hook_pid == 0){

1418

/* Child */

1419

/* Raise privileges */

1420

errno = 0;

1421

ret = seteuid(0);

1422

if(ret == -1){

1423

perror_plus("seteuid");

1424

}

1425

/* Raise privileges even more */

1426

errno = 0;

1427

ret = setuid(0);

1428

if(ret == -1){

1429

perror_plus("setuid");

1430

}

1431

/* Set group */

1432

errno = 0;

1433

ret = setgid(0);

1434

if(ret == -1){

1435

perror_plus("setgid");

1436

}

1437

/* Reset supplementary groups */

1438

errno = 0;

1439

ret = setgroups(0, NULL);

1440

if(ret == -1){

1441

perror_plus("setgroups");

1442

}

1443

dup2(devnull, STDIN_FILENO);

1444

close(devnull);

1445

dup2(STDERR_FILENO, STDOUT_FILENO);

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

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

1462

if(ret == -1){

1463

perror_plus("setenv");

1464

_exit(EX_OSERR);

1465

}

1466

char *delaystring;

1467

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

1468

if(ret == -1){

1469

perror_plus("asprintf");

1470

_exit(EX_OSERR);

1471

}

1472

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

1473

if(ret == -1){

1474

free(delaystring);

1475

perror_plus("setenv");

1476

_exit(EX_OSERR);

1477

}

1996

1478

free(delaystring);

1997

perror_plus("setenv");

1998

_exit(EX_OSERR);

1999

}

2000

free(delaystring);

2001

if(connect_to != NULL){

2002

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

2003

if(ret == -1){

2004

perror_plus("setenv");

2005

_exit(EX_OSERR);

2006

}

2007

}

2008

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

2009

direntry->d_name,

2010

O_RDONLY));

2011

if(hook_fd == -1){

2012

perror_plus("openat");

2013

_exit(EXIT_FAILURE);

2014

}

2015

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

2016

perror_plus("close");

2017

_exit(EXIT_FAILURE);

2018

}

2019

ret = dup2(devnull, STDIN_FILENO);

2020

if(ret == -1){

2021

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

2022

_exit(EX_OSERR);

2023

}

2024

ret = close(devnull);

2025

if(ret == -1){

2026

perror_plus("close");

2027

_exit(EX_OSERR);

2028

}

2029

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2030

if(ret == -1){

2031

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

2032

_exit(EX_OSERR);

2033

}

2034

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

2035

environ) == -1){

2036

perror_plus("fexecve");

2037

_exit(EXIT_FAILURE);

2038

}

2039

} else {

2040

if(hook_pid == -1){

2041

perror_plus("fork");

2042

free(direntry);

2043

continue;

2044

}

2045

int status;

2046

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

2047

perror_plus("waitpid");

2048

free(direntry);

2049

continue;

2050

}

2051

if(WIFEXITED(status)){

2052

if(WEXITSTATUS(status) != 0){

2053

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

2054

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

2055

WEXITSTATUS(status));

2056

free(direntry);

2057

continue;

2058

}

2059

} else if(WIFSIGNALED(status)){

2060

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

2061

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

2062

WTERMSIG(status));

2063

free(direntry);

2064

continue;

2065

} else {

2066

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

2067

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

2068

free(direntry);

2069

continue;

2070

}

2071

}

2072

if(debug){

2073

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

2074

direntry->d_name);

2075

}

2076

free(direntry);

2077

}

2078

free(direntries);

2079

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

2080

perror_plus("close");

2081

} else {

2082

hookdir_fd = -1;

2083

}

2084

close(devnull);

2085

}

2086

2087

__attribute__((nonnull, warn_unused_result))

2088

int bring_up_interface(const char *const interface,

2089

const float delay){

2090

int old_errno = errno;

2091

int ret;

2092

struct ifreq network;

2093

unsigned int if_index = if_nametoindex(interface);

2094

if(if_index == 0){

2095

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

2096

errno = old_errno;

2097

return ENXIO;

2098

}

2099

2100

if(quit_now){

2101

errno = old_errno;

2102

return EINTR;

2103

}

2104

2105

if(not interface_is_up(interface)){

2106

int ret_errno = 0;

2107

int ioctl_errno = 0;

2108

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

2109

ret_errno = errno;

2110

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

2111

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

2112

errno = old_errno;

2113

return ret_errno;

2114

}

2115

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

2116

2117

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

2118

if(sd == -1){

2119

ret_errno = errno;

2120

perror_plus("socket");

2121

errno = old_errno;

2122

return ret_errno;

2123

}

2124

2125

if(quit_now){

2126

ret = close(sd);

2127

if(ret == -1){

2128

perror_plus("close");

2129

}

2130

errno = old_errno;

2131

return EINTR;

2132

}

2133

2134

if(debug){

2135

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

2136

interface);

2137

}

2138

2139

/* Raise privileges */

2140

ret_errno = raise_privileges();

2141

if(ret_errno != 0){

2142

errno = ret_errno;

2143

perror_plus("Failed to raise privileges");

2144

}

2145

2146

#ifdef __linux__

2147

int ret_linux;

2148

bool restore_loglevel = false;

2149

if(ret_errno == 0){

2150

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2151

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

2152

ret_linux = klogctl(8, NULL, 5);

2153

if(ret_linux == -1){

2154

perror_plus("klogctl");

2155

} else {

2156

restore_loglevel = true;

2157

}

2158

}

2159

#endif /* __linux__ */

2160

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

2161

ioctl_errno = errno;

2162

#ifdef __linux__

2163

if(restore_loglevel){

2164

ret_linux = klogctl(7, NULL, 0);

2165

if(ret_linux == -1){

2166

perror_plus("klogctl");

2167

}

2168

}

2169

#endif /* __linux__ */

2170

2171

/* If raise_privileges() succeeded above */

2172

if(ret_errno == 0){

2173

/* Lower privileges */

2174

ret_errno = lower_privileges();

2175

if(ret_errno != 0){

2176

errno = ret_errno;

2177

perror_plus("Failed to lower privileges");

2178

}

2179

}

2180

2181

/* Close the socket */

2182

ret = close(sd);

2183

if(ret == -1){

2184

perror_plus("close");

2185

}

2186

2187

if(ret_setflags == -1){

2188

errno = ioctl_errno;

2189

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2190

errno = old_errno;

2191

return ioctl_errno;

2192

}

2193

} else if(debug){

2194

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

2195

interface);

2196

}

2197

2198

/* Sleep checking until interface is running.

2199

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

2200

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

2201

if(interface_is_running(interface)){

2202

break;

2203

}

2204

struct timespec sleeptime = { .tv_nsec = 250000000 };

2205

ret = nanosleep(&sleeptime, NULL);

2206

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

2207

perror_plus("nanosleep");

2208

}

2209

}

2210

2211

errno = old_errno;

2212

return 0;

2213

}

2214

2215

__attribute__((nonnull, warn_unused_result))

2216

int take_down_interface(const char *const interface){

2217

int old_errno = errno;

2218

struct ifreq network;

2219

unsigned int if_index = if_nametoindex(interface);

2220

if(if_index == 0){

2221

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

2222

errno = old_errno;

2223

return ENXIO;

2224

}

2225

if(interface_is_up(interface)){

2226

int ret_errno = 0;

2227

int ioctl_errno = 0;

2228

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

2229

ret_errno = errno;

2230

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

2231

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

2232

errno = old_errno;

2233

return ret_errno;

2234

}

2235

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

2236

2237

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

2238

if(sd == -1){

2239

ret_errno = errno;

2240

perror_plus("socket");

2241

errno = old_errno;

2242

return ret_errno;

2243

}

2244

2245

if(debug){

2246

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

2247

interface);

2248

}

2249

2250

/* Raise privileges */

2251

ret_errno = raise_privileges();

2252

if(ret_errno != 0){

2253

errno = ret_errno;

2254

perror_plus("Failed to raise privileges");

2255

}

2256

2257

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

2258

ioctl_errno = errno;

2259

2260

/* If raise_privileges() succeeded above */

2261

if(ret_errno == 0){

2262

/* Lower privileges */

2263

ret_errno = lower_privileges();

2264

if(ret_errno != 0){

2265

errno = ret_errno;

2266

perror_plus("Failed to lower privileges");

2267

}

2268

}

2269

2270

/* Close the socket */

2271

int ret = close(sd);

2272

if(ret == -1){

2273

perror_plus("close");

2274

}

2275

2276

if(ret_setflags == -1){

2277

errno = ioctl_errno;

2278

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2279

errno = old_errno;

2280

return ioctl_errno;

2281

}

2282

} else if(debug){

2283

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

2284

interface);

2285

}

2286

2287

errno = old_errno;

2288

return 0;

1479

if(connect_to != NULL){

1480

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

1481

if(ret == -1){

1482

perror_plus("setenv");

1483

_exit(EX_OSERR);

1484

}

1485

}

1486

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

1487

perror_plus("execl");

1488

_exit(EXIT_FAILURE);

1489

}

1490

} else {

1491

int status;

1492

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

1493

perror_plus("waitpid");

1494

free(fullname);

1495

continue;

1496

}

1497

if(WIFEXITED(status)){

1498

if(WEXITSTATUS(status) != 0){

1499

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

1500

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

1501

WEXITSTATUS(status));

1502

free(fullname);

1503

continue;

1504

}

1505

} else if(WIFSIGNALED(status)){

1506

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

1507

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

1508

WTERMSIG(status));

1509

free(fullname);

1510

continue;

1511

} else {

1512

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

1513

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

1514

free(fullname);

1515

continue;

1516

}

1517

}

1518

free(fullname);

1519

if(debug){

1520

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

1521

direntry->d_name);

1522

}

1523

}

1524

close(devnull);

1525

}

1526

return true;

2289

1527

}

2290

1528

2291

1529

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

2292

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

2293

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

2294

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

2295

.current_server = NULL, .interfaces = NULL,

2296

.interfaces_size = 0 };

2297

1530

AvahiSServiceBrowser *sb = NULL;

2298

error_t ret_errno;

1531

int error;

2299

1532

int ret;

2300

1533

intmax_t tmpmax;

2301

1534

char *tmp;

2302

1535

int exitcode = EXIT_SUCCESS;

2303

char *interfaces_to_take_down = NULL;

2304

size_t interfaces_to_take_down_size = 0;

2305

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

2306

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

2307

char *tempdir = NULL;

1536

const char *interface = "";

1537

struct ifreq network;

1538

int sd = -1;

1539

bool take_down_interface = false;

1540

uid_t uid;

1541

gid_t gid;

1542

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

1543

bool tempdir_created = false;

2308

1544

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2309

1545

const char *seckey = PATHDIR "/" SECKEY;

2310

1546

const char *pubkey = PATHDIR "/" PUBKEY;

2311

const char *dh_params_file = NULL;

2312

char *interfaces_hooks = NULL;

2313

1547

2314

1548

bool gnutls_initialized = false;

2315

1549

bool gpgme_initialized = false;

2367

1601

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

2368

1602

" Diffie-Hellman key exchange",

2369

1603

.group = 2 },

2370

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

2371

.arg = "FILE",

2372

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

2373

" for the Diffie-Hellman key exchange",

2374

.group = 2 },

2375

1604

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

2376

1605

.arg = "STRING",

2377

1606

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

2411

1640

connect_to = arg;

2412

1641

break;

2413

1642

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

2414

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

2415

arg, (int)',');

2416

if(ret_errno != 0){

2417

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

2418

}

1643

interface = arg;

2419

1644

break;

2420

1645

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

2421

1646

seckey = arg;

2432

1657

}

2433

1658

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

2434

1659

break;

2435

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

2436

dh_params_file = arg;

2437

break;

2438

1660

case 130: /* --priority */

2439

1661

mc.priority = arg;

2440

1662

break;

2480

1702

.args_doc = "",

2481

1703

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

2482

1704

" passwords from a Mandos server" };

2483

ret_errno = argp_parse(&argp, argc, argv,

2484

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2485

switch(ret_errno){

1705

ret = argp_parse(&argp, argc, argv,

1706

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1707

switch(ret){

2486

1708

case 0:

2487

1709

break;

2488

1710

case ENOMEM:

2489

1711

default:

2490

errno = ret_errno;

1712

errno = ret;

2491

1713

perror_plus("argp_parse");

2492

1714

exitcode = EX_OSERR;

2493

1715

goto end;

2496

1718

goto end;

2497

1719

}

2498

1720

}

2499

1721

2500

1722

{

2501

1723

/* Work around Debian bug #633582:

2502

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

1724

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

2503

1725

2504

/* Re-raise privileges */

2505

ret = raise_privileges();

2506

if(ret != 0){

2507

errno = ret;

2508

perror_plus("Failed to raise privileges");

1726

/* Re-raise priviliges */

1727

errno = 0;

1728

ret = seteuid(0);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2509

1731

} else {

2510

1732

struct stat st;

2511

1733

2526

1748

}

2527

1749

}

2528

1750

}

2529

close(seckey_fd);

1751

TEMP_FAILURE_RETRY(close(seckey_fd));

2530

1752

}

2531

1753

}

2532

1754

2533

1755

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

2534

1756

int pubkey_fd = open(pubkey, O_RDONLY);

2535

1757

if(pubkey_fd == -1){

2547

1769

}

2548

1770

}

2549

1771

}

2550

close(pubkey_fd);

2551

}

2552

}

2553

2554

if(dh_params_file != NULL

2555

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

2556

int dhparams_fd = open(dh_params_file, O_RDONLY);

2557

if(dhparams_fd == -1){

2558

perror_plus("open");

2559

} else {

2560

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

2561

if(ret == -1){

2562

perror_plus("fstat");

2563

} else {

2564

if(S_ISREG(st.st_mode)

2565

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

2566

ret = fchown(dhparams_fd, uid, gid);

2567

if(ret == -1){

2568

perror_plus("fchown");

2569

}

2570

}

2571

}

2572

close(dhparams_fd);

2573

}

2574

}

2575

1772

TEMP_FAILURE_RETRY(close(pubkey_fd));

1773

}

1774

}

1775

2576

1776

/* Lower privileges */

2577

ret = lower_privileges();

2578

if(ret != 0){

2579

errno = ret;

2580

perror_plus("Failed to lower privileges");

2581

}

2582

}

2583

}

2584

2585

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

2586

{

2587

char *interface = NULL;

2588

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

2589

interface))){

2590

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

2591

and if_nametoindex(interface) == 0){

2592

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

2593

fprintf_plus(stderr, "Not using nonexisting interface"

2594

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

2595

}

2596

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

2597

interface = NULL;

1777

errno = 0;

1778

ret = seteuid(uid);

1779

if(ret == -1){

1780

perror_plus("seteuid");

2598

1781

}

2599

1782

}

2600

1783

}

2601

1784

2602

1785

/* Run network hooks */

2603

{

2604

if(mc.interfaces != NULL){

2605

interfaces_hooks = malloc(mc.interfaces_size);

2606

if(interfaces_hooks == NULL){

2607

perror_plus("malloc");

2608

goto end;

2609

}

2610

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

2611

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

2612

}

2613

run_network_hooks("start", interfaces_hooks != NULL ?

2614

interfaces_hooks : "", delay);

1786

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

1787

goto end;

2615

1788

}

2616

1789

2617

1790

if(not debug){

2618

1791

avahi_set_log_function(empty_log);

2619

1792

}

2620

1793

1794

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

1795

struct dirent **direntries;

1796

/* First look for interfaces that are up */

1797

ret = scandir(sys_class_net, &direntries, up_interface,

1798

alphasort);

1799

if(ret == 0){

1800

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

1801

free(direntries);

1802

ret = scandir(sys_class_net, &direntries, good_interface,

1803

alphasort);

1804

}

1805

if(ret >= 1){

1806

/* Pick the first interface returned */

1807

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

1808

if(debug){

1809

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

1810

}

1811

if(interface == NULL){

1812

perror_plus("malloc");

1813

free(direntries);

1814

exitcode = EXIT_FAILURE;

1815

goto end;

1816

}

1817

free(direntries);

1818

} else {

1819

free(direntries);

1820

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

1821

exitcode = EXIT_FAILURE;

1822

goto end;

1823

}

1824

}

1825

2621

1826

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

2622

1827

from the signal handler */

2623

1828

/* Initialize the pseudo-RNG for Avahi */

2624

1829

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

2625

simple_poll = avahi_simple_poll_new();

2626

if(simple_poll == NULL){

1830

mc.simple_poll = avahi_simple_poll_new();

1831

if(mc.simple_poll == NULL){

2627

1832

fprintf_plus(stderr,

2628

1833

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

2629

1834

exitcode = EX_UNAVAILABLE;

2693

1898

}

2694

1899

}

2695

1900

2696

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

2697

if(mc.interfaces == NULL){

2698

struct dirent **direntries = NULL;

2699

/* Look for any good interfaces */

2700

ret = scandir(sys_class_net, &direntries, good_interface,

2701

alphasort);

2702

if(ret >= 1){

2703

/* Add all found interfaces to interfaces list */

2704

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

2705

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

2706

direntries[i]->d_name);

2707

if(ret_errno != 0){

2708

errno = ret_errno;

2709

perror_plus("argz_add");

2710

free(direntries[i]);

2711

continue;

2712

}

2713

if(debug){

2714

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

2715

direntries[i]->d_name);

2716

}

2717

free(direntries[i]);

2718

}

2719

free(direntries);

2720

} else {

2721

if(ret == 0){

2722

free(direntries);

2723

}

2724

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

2725

exitcode = EXIT_FAILURE;

2726

goto end;

2727

}

2728

}

2729

2730

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

2731

{

2732

char *interface = NULL;

2733

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

2734

interface))){

2735

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

2736

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

2737

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

2738

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

2739

interface);

2740

interface = NULL;

2741

while((interface = argz_next(mc.interfaces,

2742

mc.interfaces_size, interface))){

2743

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

2744

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

2745

interface);

2746

interface = NULL;

1901

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

1902

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

1903

if_index = (AvahiIfIndex) if_nametoindex(interface);

1904

if(if_index == 0){

1905

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

1906

exitcode = EX_UNAVAILABLE;

1907

goto end;

1908

}

1909

1910

if(quit_now){

1911

goto end;

1912

}

1913

1914

/* Re-raise priviliges */

1915

errno = 0;

1916

ret = seteuid(0);

1917

if(ret == -1){

1918

perror_plus("seteuid");

1919

}

1920

1921

#ifdef __linux__

1922

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1923

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

1924

ret = klogctl(8, NULL, 5);

1925

bool restore_loglevel = true;

1926

if(ret == -1){

1927

restore_loglevel = false;

1928

perror_plus("klogctl");

1929

}

1930

#endif /* __linux__ */

1931

1932

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1933

if(sd < 0){

1934

perror_plus("socket");

1935

exitcode = EX_OSERR;

1936

#ifdef __linux__

1937

if(restore_loglevel){

1938

ret = klogctl(7, NULL, 0);

1939

if(ret == -1){

1940

perror_plus("klogctl");

1941

}

1942

}

1943

#endif /* __linux__ */

1944

/* Lower privileges */

1945

errno = 0;

1946

ret = seteuid(uid);

1947

if(ret == -1){

1948

perror_plus("seteuid");

1949

}

1950

goto end;

1951

}

1952

strcpy(network.ifr_name, interface);

1953

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

1954

if(ret == -1){

1955

perror_plus("ioctl SIOCGIFFLAGS");

1956

#ifdef __linux__

1957

if(restore_loglevel){

1958

ret = klogctl(7, NULL, 0);

1959

if(ret == -1){

1960

perror_plus("klogctl");

1961

}

1962

}

1963

#endif /* __linux__ */

1964

exitcode = EX_OSERR;

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

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

1974

network.ifr_flags |= IFF_UP;

1975

take_down_interface = true;

1976

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

1977

if(ret == -1){

1978

take_down_interface = false;

1979

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1980

exitcode = EX_OSERR;

1981

#ifdef __linux__

1982

if(restore_loglevel){

1983

ret = klogctl(7, NULL, 0);

1984

if(ret == -1){

1985

perror_plus("klogctl");

2747

1986

}

2748

1987

}

1988

#endif /* __linux__ */

1989

/* Lower privileges */

1990

errno = 0;

1991

ret = seteuid(uid);

1992

if(ret == -1){

1993

perror_plus("seteuid");

1994

}

1995

goto end;

1996

}

1997

}

1998

/* Sleep checking until interface is running.

1999

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

2000

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

2001

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

2002

if(ret == -1){

2003

perror_plus("ioctl SIOCGIFFLAGS");

2004

} else if(network.ifr_flags & IFF_RUNNING){

2749

2005

break;

2750

2006

}

2751

bool interface_was_up = interface_is_up(interface);

2752

errno = bring_up_interface(interface, delay);

2753

if(not interface_was_up){

2754

if(errno != 0){

2755

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

2756

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

2757

} else {

2758

errno = argz_add(&interfaces_to_take_down,

2759

&interfaces_to_take_down_size,

2760

interface);

2761

if(errno != 0){

2762

perror_plus("argz_add");

2763

}

2764

}

2765

}

2766

}

2767

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

2768

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

2769

}

2770

}

2771

2772

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

2773

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

2774

if(debug){

2775

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

2776

mc.interfaces);

2777

}

2778

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

2007

struct timespec sleeptime = { .tv_nsec = 250000000 };

2008

ret = nanosleep(&sleeptime, NULL);

2009

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

2010

perror_plus("nanosleep");

2011

}

2012

}

2013

if(not take_down_interface){

2014

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

2015

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

2016

if(ret == -1){

2017

perror_plus("close");

2018

}

2019

}

2020

#ifdef __linux__

2021

if(restore_loglevel){

2022

/* Restores kernel loglevel to default */

2023

ret = klogctl(7, NULL, 0);

2024

if(ret == -1){

2025

perror_plus("klogctl");

2026

}

2027

}

2028

#endif /* __linux__ */

2029

/* Lower privileges */

2030

errno = 0;

2031

/* Lower privileges */

2032

ret = seteuid(uid);

2033

if(ret == -1){

2034

perror_plus("seteuid");

2035

}

2779

2036

}

2780

2037

2781

2038

if(quit_now){

2782

2039

goto end;

2783

2040

}

2784

2041

2785

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

2042

ret = init_gnutls_global(pubkey, seckey);

2786

2043

if(ret == -1){

2787

2044

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

2788

2045

exitcode = EX_UNAVAILABLE;

2795

2052

goto end;

2796

2053

}

2797

2054

2798

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

2799

tempdir = mkdtemp(run_tempdir);

2800

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

2801

if(debug){

2802

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

2803

run_tempdir, old_tempdir);

2804

}

2805

tempdir = mkdtemp(old_tempdir);

2806

}

2807

if(tempdir == NULL){

2055

if(mkdtemp(tempdir) == NULL){

2808

2056

perror_plus("mkdtemp");

2809

2057

goto end;

2810

2058

}

2059

tempdir_created = true;

2811

2060

2812

2061

if(quit_now){

2813

2062

goto end;

2814

2063

}

2815

2064

2816

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

2065

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

2817

2066

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

2818

2067

exitcode = EX_UNAVAILABLE;

2819

2068

goto end;

2829

2078

/* Connect directly, do not use Zeroconf */

2830

2079

/* (Mainly meant for debugging) */

2831

2080

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

2832

2833

2081

if(address == NULL){

2834

2082

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

2835

2083

exitcode = EX_USAGE;

2840

2088

goto end;

2841

2089

}

2842

2090

2843

in_port_t port;

2091

uint16_t port;

2844

2092

errno = 0;

2845

2093

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

2846

2094

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

2847

or tmpmax != (in_port_t)tmpmax){

2095

or tmpmax != (uint16_t)tmpmax){

2848

2096

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

2849

2097

exitcode = EX_USAGE;

2850

2098

goto end;

2851

2099

}

2852

2100

2853

2101

if(quit_now){

2854

2102

goto end;

2855

2103

}

2856

2104

2857

port = (in_port_t)tmpmax;

2105

port = (uint16_t)tmpmax;

2858

2106

*address = '\0';

2859

2107

/* Colon in address indicates IPv6 */

2860

2108

int af;

2876

2124

}

2877

2125

2878

2126

while(not quit_now){

2879

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

2880

&mc);

2127

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

2881

2128

if(quit_now or ret == 0){

2882

2129

break;

2883

2130

}

2885

2132

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

2886

2133

(int)retry_interval);

2887

2134

}

2888

sleep((unsigned int)retry_interval);

2135

sleep((int)retry_interval);

2889

2136

}

2890

2137

2891

if(not quit_now){

2138

if (not quit_now){

2892

2139

exitcode = EXIT_SUCCESS;

2893

2140

}

2894

2141

2909

2156

config.publish_domain = 0;

2910

2157

2911

2158

/* Allocate a new server */

2912

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2913

&config, NULL, NULL, &ret);

2159

mc.server = avahi_server_new(avahi_simple_poll_get

2160

(mc.simple_poll), &config, NULL,

2161

NULL, &error);

2914

2162

2915

2163

/* Free the Avahi configuration data */

2916

2164

avahi_server_config_free(&config);

2919

2167

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

2920

2168

if(mc.server == NULL){

2921

2169

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

2922

avahi_strerror(ret));

2170

avahi_strerror(error));

2923

2171

exitcode = EX_UNAVAILABLE;

2924

2172

goto end;

2925

2173

}

2931

2179

/* Create the Avahi service browser */

2932

2180

sb = avahi_s_service_browser_new(mc.server, if_index,

2933

2181

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2934

NULL, 0, browse_callback,

2935

(void *)&mc);

2182

NULL, 0, browse_callback, NULL);

2936

2183

if(sb == NULL){

2937

2184

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

2938

2185

avahi_strerror(avahi_server_errno(mc.server)));

2949

2196

if(debug){

2950

2197

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

2951

2198

}

2952

2953

ret = avahi_loop_with_timeout(simple_poll,

2954

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

2199

2200

ret = avahi_loop_with_timeout(mc.simple_poll,

2201

(int)(retry_interval * 1000));

2955

2202

if(debug){

2956

2203

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

2957

2204

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

2960

2207

end:

2961

2208

2962

2209

if(debug){

2963

if(signal_received){

2964

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

2965

argv[0], signal_received,

2966

strsignal(signal_received));

2967

} else {

2968

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

2969

}

2210

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

2970

2211

}

2971

2212

2972

2213

/* Cleanup things */

2973

free(mc.interfaces);

2974

2975

2214

if(sb != NULL)

2976

2215

avahi_s_service_browser_free(sb);

2977

2216

2978

2217

if(mc.server != NULL)

2979

2218

avahi_server_free(mc.server);

2980

2219

2981

if(simple_poll != NULL)

2982

avahi_simple_poll_free(simple_poll);

2220

if(mc.simple_poll != NULL)

2221

avahi_simple_poll_free(mc.simple_poll);

2983

2222

2984

2223

if(gnutls_initialized){

2985

2224

gnutls_certificate_free_credentials(mc.cred);

2225

gnutls_global_deinit();

2986

2226

gnutls_dh_params_deinit(mc.dh_params);

2987

2227

}

2988

2228

2996

2236

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

2997

2237

while(mc.current_server != NULL){

2998

2238

server *next = mc.current_server->next;

2999

#ifdef __GNUC__

3000

#pragma GCC diagnostic push

3001

#pragma GCC diagnostic ignored "-Wcast-qual"

3002

#endif

3003

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

3004

#ifdef __GNUC__

3005

#pragma GCC diagnostic pop

3006

#endif

3007

2239

free(mc.current_server);

3008

2240

mc.current_server = next;

3009

2241

}

3010

2242

}

3011

2243

3012

/* Re-raise privileges */

2244

/* Run network hooks */

2245

run_network_hooks("stop", interface, delay);

2246

2247

/* Re-raise priviliges */

3013

2248

{

3014

ret = raise_privileges();

3015

if(ret != 0){

3016

errno = ret;

3017

perror_plus("Failed to raise privileges");

3018

} else {

3019

3020

/* Run network hooks */

3021

run_network_hooks("stop", interfaces_hooks != NULL ?

3022

interfaces_hooks : "", delay);

3023

3024

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

3025

{

3026

char *interface = NULL;

3027

while((interface = argz_next(interfaces_to_take_down,

3028

interfaces_to_take_down_size,

3029

interface))){

3030

ret = take_down_interface(interface);

3031

if(ret != 0){

3032

errno = ret;

3033

perror_plus("Failed to take down interface");

3034

}

3035

}

3036

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

3037

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

3038

" down\n");

3039

}

3040

}

2249

errno = 0;

2250

ret = seteuid(0);

2251

if(ret == -1){

2252

perror_plus("seteuid");

3041

2253

}

3042

2254

3043

ret = lower_privileges_permanently();

3044

if(ret != 0){

3045

errno = ret;

3046

perror_plus("Failed to lower privileges permanently");

2255

/* Take down the network interface */

2256

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

2257

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

2258

if(ret == -1){

2259

perror_plus("ioctl SIOCGIFFLAGS");

2260

} else if(network.ifr_flags & IFF_UP){

2261

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

2262

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

2263

if(ret == -1){

2264

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2265

}

2266

}

2267

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

2268

if(ret == -1){

2269

perror_plus("close");

2270

}

3047

2271

}

3048

2272

}

3049

3050

free(interfaces_to_take_down);

3051

free(interfaces_hooks);

3052

3053

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

3054

uintmax_t level){

2273

/* Lower privileges permanently */

2274

errno = 0;

2275

ret = setuid(uid);

2276

if(ret == -1){

2277

perror_plus("setuid");

2278

}

2279

2280

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

2281

if(tempdir_created){

3055

2282

struct dirent **direntries = NULL;

3056

int dret;

3057

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

3058

O_RDONLY

3059

| O_NOFOLLOW

3060

| O_DIRECTORY

3061

| O_PATH));

3062

if(dir_fd == -1){

3063

perror_plus("open");

3064

}

3065

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

3066

notdotentries, alphasort);

3067

if(numentries >= 0){

2283

struct dirent *direntry = NULL;

2284

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

2285

alphasort);

2286

if (numentries > 0){

3068

2287

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

3069

if(debug){

3070

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

3071

dirname, direntries[i]->d_name);

3072

}

3073

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

3074

if(dret == -1){

3075

if(errno == EISDIR){

3076

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

3077

AT_REMOVEDIR);

3078

}

3079

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

3080

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

3081

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

3082

/* Recurse only in this special case */

3083

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

3084

dret = 0;

3085

}

3086

if(dret == -1){

3087

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

3088

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

3089

}

3090

}

3091

free(direntries[i]);

3092

}

3093

3094

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

3095

free(direntries);

3096

if(numentries == -1){

3097

perror_plus("scandirat");

3098

}

3099

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3100

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

3101

perror_plus("rmdir");

3102

}

3103

} else {

3104

perror_plus("scandirat");

3105

}

3106

close(dir_fd);

3107

}

3108

3109

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

3110

if(tempdir != NULL){

3111

clean_dir_at(-1, tempdir, 0);

2288

direntry = direntries[i];

2289

char *fullname = NULL;

2290

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

2291

direntry->d_name);

2292

if(ret < 0){

2293

perror_plus("asprintf");

2294

continue;

2295

}

2296

ret = remove(fullname);

2297

if(ret == -1){

2298

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

2299

strerror(errno));

2300

}

2301

free(fullname);

2302

}

2303

}

2304

2305

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

2306

free(direntries);

2307

if (numentries == -1){

2308

perror_plus("scandir");

2309

}

2310

ret = rmdir(tempdir);

2311

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

2312

perror_plus("rmdir");

2313

}

3112

2314

}

3113

2315

3114

2316

if(quit_now){