/mandos/trunk : revision 873

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

10

*

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* Everything else is

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13

12

13

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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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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40

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

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

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stdout, ferror(), remove() */

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

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stdout, ferror() */

44

#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 */

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

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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inet_pton(), connect(),

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getnameinfo() */

61

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

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

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63

*/

62

64

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

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65

strtoimax() */

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

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

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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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71

program_invocation_short_name */

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

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

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*/

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79

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

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

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

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

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

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unlinkat() */

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

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84

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

79

85

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

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argp_state, struct argp,

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94

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

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WEXITSTATUS(), WTERMSIG() */

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96

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

101

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

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EAI_SYSTEM, gai_strerror() */

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103

92

104

#ifdef __linux__

93

105

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

135

147

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

136

148

char *connect_to = NULL;

137

149

const char *hookdir = HOOKDIR;

150

int hookdir_fd = -1;

151

uid_t uid = 65534;

152

gid_t gid = 65534;

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153

139

154

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

140

155

typedef struct server{

141

156

const char *ip;

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uint16_t port;

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in_port_t port;

143

158

AvahiIfIndex if_index;

144

159

int af;

145

160

struct timespec last_seen;

149

164

150

165

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

151

166

typedef struct {

152

AvahiSimplePoll *simple_poll;

153

167

AvahiServer *server;

154

168

gnutls_certificate_credentials_t cred;

155

169

unsigned int dh_bits;

157

171

const char *priority;

158

172

gpgme_ctx_t ctx;

159

173

server *current_server;

174

char *interfaces;

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size_t interfaces_size;

160

176

} mandos_context;

161

177

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

163

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

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.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

178

/* global so signal handler can reach it*/

179

AvahiSimplePoll *simple_poll;

167

180

168

181

sig_atomic_t quit_now = 0;

169

182

int signal_received = 0;

170

183

171

184

/* Function to use when printing errors */

172

185

void perror_plus(const char *print_text){

186

int e = errno;

173

187

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

174

188

program_invocation_short_name);

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errno = e;

175

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perror(print_text);

176

191

}

177

192

178

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

193

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

179

194

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

180

195

va_list ap;

181

196

va_start (ap, format);

182

197

183

198

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

184

199

program_invocation_short_name));

185

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

200

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

186

201

}

187

202

188

203

/*

190

205

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

191

206

* "buffer_length" is how much is already used.

192

207

*/

208

__attribute__((nonnull, warn_unused_result))

193

209

size_t incbuffer(char **buffer, size_t buffer_length,

194

210

size_t buffer_capacity){

195

211

if(buffer_length + BUFFER_SIZE > buffer_capacity){

196

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

197

if(buffer == NULL){

212

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

213

if(new_buf == NULL){

214

int old_errno = errno;

215

free(*buffer);

216

errno = old_errno;

217

*buffer = NULL;

198

218

return 0;

199

219

}

220

*buffer = new_buf;

200

221

buffer_capacity += BUFFER_SIZE;

201

222

}

202

223

return buffer_capacity;

203

224

}

204

225

205

226

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

206

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

207

int af){

227

__attribute__((nonnull, warn_unused_result))

228

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

229

int af, server **current_server){

208

230

int ret;

209

231

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

210

232

if(new_server == NULL){

217

239

.af = af };

218

240

if(new_server->ip == NULL){

219

241

perror_plus("strdup");

242

free(new_server);

243

return false;

244

}

245

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

246

if(ret == -1){

247

perror_plus("clock_gettime");

248

#ifdef __GNUC__

249

#pragma GCC diagnostic push

250

#pragma GCC diagnostic ignored "-Wcast-qual"

251

#endif

252

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

253

#ifdef __GNUC__

254

#pragma GCC diagnostic pop

255

#endif

256

free(new_server);

220

257

return false;

221

258

}

222

259

/* Special case of first server */

223

if (mc.current_server == NULL){

260

if(*current_server == NULL){

224

261

new_server->next = new_server;

225

262

new_server->prev = new_server;

226

mc.current_server = new_server;

227

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

263

*current_server = new_server;

228

264

} else {

229

new_server->next = mc.current_server;

230

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

265

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

266

new_server->next = *current_server;

267

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

231

268

new_server->prev->next = new_server;

232

mc.current_server->prev = new_server;

233

}

234

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

235

if(ret == -1){

236

perror_plus("clock_gettime");

237

return false;

269

(*current_server)->prev = new_server;

238

270

}

239

271

return true;

240

272

}

242

274

/*

243

275

* Initialize GPGME.

244

276

*/

245

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

246

const char *tempdir){

277

__attribute__((nonnull, warn_unused_result))

278

static bool init_gpgme(const char * const seckey,

279

const char * const pubkey,

280

const char * const tempdir,

281

mandos_context *mc){

247

282

gpgme_error_t rc;

248

283

gpgme_engine_info_t engine_info;

249

284

250

251

285

/*

252

286

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

253

287

*/

254

bool import_key(const char *filename){

288

bool import_key(const char * const filename){

255

289

int ret;

256

290

int fd;

257

291

gpgme_data_t pgp_data;

269

303

return false;

270

304

}

271

305

272

rc = gpgme_op_import(mc.ctx, pgp_data);

306

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

273

307

if(rc != GPG_ERR_NO_ERROR){

274

308

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

275

309

gpgme_strsource(rc), gpgme_strerror(rc));

276

310

return false;

277

311

}

278

312

279

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

313

ret = close(fd);

280

314

if(ret == -1){

281

315

perror_plus("close");

282

316

}

319

353

}

320

354

321

355

/* Create new GPGME "context" */

322

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

356

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

323

357

if(rc != GPG_ERR_NO_ERROR){

324

358

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

325

359

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

338

372

* Decrypt OpenPGP data.

339

373

* Returns -1 on error

340

374

*/

375

__attribute__((nonnull, warn_unused_result))

341

376

static ssize_t pgp_packet_decrypt(const char *cryptotext,

342

377

size_t crypto_size,

343

char **plaintext){

378

char **plaintext,

379

mandos_context *mc){

344

380

gpgme_data_t dh_crypto, dh_plain;

345

381

gpgme_error_t rc;

346

382

ssize_t ret;

372

408

373

409

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

374

410

data buffer */

375

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

411

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

376

412

if(rc != GPG_ERR_NO_ERROR){

377

413

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

378

414

gpgme_strsource(rc), gpgme_strerror(rc));

379

415

plaintext_length = -1;

380

416

if(debug){

381

417

gpgme_decrypt_result_t result;

382

result = gpgme_op_decrypt_result(mc.ctx);

418

result = gpgme_op_decrypt_result(mc->ctx);

383

419

if(result == NULL){

384

420

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

385

421

} else {

462

498

return plaintext_length;

463

499

}

464

500

465

static const char * safer_gnutls_strerror(int value){

466

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

467

-Wunreachable-code */

468

if(ret == NULL)

469

ret = "(unknown)";

470

return ret;

501

__attribute__((warn_unused_result, const))

502

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

503

if(str == NULL)

504

return "(unknown)";

505

return str;

506

}

507

508

__attribute__((warn_unused_result))

509

static const char *safer_gnutls_strerror(int value){

510

const char *ret = gnutls_strerror(value);

511

return safe_string(ret);

471

512

}

472

513

473

514

/* GnuTLS log function callback */

515

__attribute__((nonnull))

474

516

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

475

517

const char* string){

476

518

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

477

519

}

478

520

521

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

479

522

static int init_gnutls_global(const char *pubkeyfilename,

480

const char *seckeyfilename){

523

const char *seckeyfilename,

524

const char *dhparamsfilename,

525

mandos_context *mc){

481

526

int ret;

527

unsigned int uret;

482

528

483

529

if(debug){

484

530

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

485

531

}

486

532

487

ret = gnutls_global_init();

488

if(ret != GNUTLS_E_SUCCESS){

489

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

490

safer_gnutls_strerror(ret));

491

return -1;

492

}

493

494

533

if(debug){

495

534

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

496

535

* - GnuTLS manual

500

539

}

501

540

502

541

/* OpenPGP credentials */

503

ret = gnutls_certificate_allocate_credentials(&mc.cred);

542

ret = gnutls_certificate_allocate_credentials(&mc->cred);

504

543

if(ret != GNUTLS_E_SUCCESS){

505

544

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

506

545

safer_gnutls_strerror(ret));

507

gnutls_global_deinit();

508

546

return -1;

509

547

}

510

548

516

554

}

517

555

518

556

ret = gnutls_certificate_set_openpgp_key_file

519

(mc.cred, pubkeyfilename, seckeyfilename,

557

(mc->cred, pubkeyfilename, seckeyfilename,

520

558

GNUTLS_OPENPGP_FMT_BASE64);

521

559

if(ret != GNUTLS_E_SUCCESS){

522

560

fprintf_plus(stderr,

528

566

}

529

567

530

568

/* GnuTLS server initialization */

531

ret = gnutls_dh_params_init(&mc.dh_params);

569

ret = gnutls_dh_params_init(&mc->dh_params);

532

570

if(ret != GNUTLS_E_SUCCESS){

533

571

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

534

572

" initialization: %s\n",

535

573

safer_gnutls_strerror(ret));

536

574

goto globalfail;

537

575

}

538

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

539

if(ret != GNUTLS_E_SUCCESS){

540

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

541

safer_gnutls_strerror(ret));

542

goto globalfail;

543

}

544

545

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

576

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

577

if(dhparamsfilename != NULL){

578

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

579

do {

580

int dhpfile = open(dhparamsfilename, O_RDONLY);

581

if(dhpfile == -1){

582

perror_plus("open");

583

dhparamsfilename = NULL;

584

break;

585

}

586

size_t params_capacity = 0;

587

while(true){

588

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

589

(size_t)params.size,

590

(size_t)params_capacity);

591

if(params_capacity == 0){

592

perror_plus("incbuffer");

593

free(params.data);

594

params.data = NULL;

595

dhparamsfilename = NULL;

596

break;

597

}

598

ssize_t bytes_read = read(dhpfile,

599

params.data + params.size,

600

BUFFER_SIZE);

601

/* EOF */

602

if(bytes_read == 0){

603

break;

604

}

605

/* check bytes_read for failure */

606

if(bytes_read < 0){

607

perror_plus("read");

608

free(params.data);

609

params.data = NULL;

610

dhparamsfilename = NULL;

611

break;

612

}

613

params.size += (unsigned int)bytes_read;

614

}

615

if(params.data == NULL){

616

dhparamsfilename = NULL;

617

}

618

if(dhparamsfilename == NULL){

619

break;

620

}

621

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

622

GNUTLS_X509_FMT_PEM);

623

if(ret != GNUTLS_E_SUCCESS){

624

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

625

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

626

safer_gnutls_strerror(ret));

627

dhparamsfilename = NULL;

628

}

629

} while(false);

630

}

631

if(dhparamsfilename == NULL){

632

if(mc->dh_bits == 0){

633

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

634

/* Try to read the private key file */

635

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

636

do {

637

int secfile = open(seckeyfilename, O_RDONLY);

638

if(secfile == -1){

639

perror_plus("open");

640

break;

641

}

642

size_t buffer_capacity = 0;

643

while(true){

644

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

645

(size_t)buffer.size,

646

(size_t)buffer_capacity);

647

if(buffer_capacity == 0){

648

perror_plus("incbuffer");

649

free(buffer.data);

650

buffer.data = NULL;

651

break;

652

}

653

ssize_t bytes_read = read(secfile,

654

buffer.data + buffer.size,

655

BUFFER_SIZE);

656

/* EOF */

657

if(bytes_read == 0){

658

break;

659

}

660

/* check bytes_read for failure */

661

if(bytes_read < 0){

662

perror_plus("read");

663

free(buffer.data);

664

buffer.data = NULL;

665

break;

666

}

667

buffer.size += (unsigned int)bytes_read;

668

}

669

close(secfile);

670

} while(false);

671

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

672

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

673

if(buffer.data != NULL){

674

{

675

gnutls_openpgp_privkey_t privkey = NULL;

676

ret = gnutls_openpgp_privkey_init(&privkey);

677

if(ret != GNUTLS_E_SUCCESS){

678

fprintf_plus(stderr, "Error initializing OpenPGP key"

679

" structure: %s",

680

safer_gnutls_strerror(ret));

681

free(buffer.data);

682

buffer.data = NULL;

683

} else {

684

ret = gnutls_openpgp_privkey_import

685

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

686

if(ret != GNUTLS_E_SUCCESS){

687

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

688

safer_gnutls_strerror(ret));

689

privkey = NULL;

690

}

691

free(buffer.data);

692

buffer.data = NULL;

693

if(privkey != NULL){

694

/* Use private key to suggest an appropriate

695

sec_param */

696

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

697

gnutls_openpgp_privkey_deinit(privkey);

698

if(debug){

699

fprintf_plus(stderr, "This OpenPGP key implies using"

700

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

701

safe_string(gnutls_sec_param_get_name

702

(sec_param)));

703

}

704

}

705

}

706

}

707

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

708

/* Err on the side of caution */

709

sec_param = GNUTLS_SEC_PARAM_ULTRA;

710

if(debug){

711

fprintf_plus(stderr, "Falling back to security parameter"

712

" \"%s\"\n",

713

safe_string(gnutls_sec_param_get_name

714

(sec_param)));

715

}

716

}

717

}

718

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

719

if(uret != 0){

720

mc->dh_bits = uret;

721

if(debug){

722

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

723

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

724

safe_string(gnutls_sec_param_get_name

725

(sec_param)),

726

mc->dh_bits);

727

}

728

} else {

729

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

730

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

731

safe_string(gnutls_sec_param_get_name

732

(sec_param)),

733

safer_gnutls_strerror(ret));

734

goto globalfail;

735

}

736

} else if(debug){

737

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

738

mc->dh_bits);

739

}

740

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

741

if(ret != GNUTLS_E_SUCCESS){

742

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

743

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

744

safer_gnutls_strerror(ret));

745

goto globalfail;

746

}

747

}

748

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

546

749

547

750

return 0;

548

751

549

752

globalfail:

550

753

551

gnutls_certificate_free_credentials(mc.cred);

552

gnutls_global_deinit();

553

gnutls_dh_params_deinit(mc.dh_params);

754

gnutls_certificate_free_credentials(mc->cred);

755

gnutls_dh_params_deinit(mc->dh_params);

554

756

return -1;

555

757

}

556

758

557

static int init_gnutls_session(gnutls_session_t *session){

759

__attribute__((nonnull, warn_unused_result))

760

static int init_gnutls_session(gnutls_session_t *session,

761

mandos_context *mc){

558

762

int ret;

559

763

/* GnuTLS session creation */

560

764

do {

572

776

{

573

777

const char *err;

574

778

do {

575

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

779

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

576

780

if(quit_now){

577

781

gnutls_deinit(*session);

578

782

return -1;

589

793

590

794

do {

591

795

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

592

mc.cred);

796

mc->cred);

593

797

if(quit_now){

594

798

gnutls_deinit(*session);

595

799

return -1;

605

809

/* ignore client certificate if any. */

606

810

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

607

811

608

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

609

610

812

return 0;

611

813

}

612

814

614

816

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

615

817

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

616

818

819

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

820

__attribute__((warn_unused_result))

821

int raise_privileges(void){

822

int old_errno = errno;

823

int ret = 0;

824

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

825

ret = errno;

826

}

827

errno = old_errno;

828

return ret;

829

}

830

831

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

832

__attribute__((warn_unused_result))

833

int raise_privileges_permanently(void){

834

int old_errno = errno;

835

int ret = raise_privileges();

836

if(ret != 0){

837

errno = old_errno;

838

return ret;

839

}

840

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

841

ret = errno;

842

}

843

errno = old_errno;

844

return ret;

845

}

846

847

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

848

__attribute__((warn_unused_result))

849

int lower_privileges(void){

850

int old_errno = errno;

851

int ret = 0;

852

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

853

ret = errno;

854

}

855

errno = old_errno;

856

return ret;

857

}

858

859

/* Lower privileges permanently */

860

__attribute__((warn_unused_result))

861

int lower_privileges_permanently(void){

862

int old_errno = errno;

863

int ret = 0;

864

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

865

ret = errno;

866

}

867

errno = old_errno;

868

return ret;

869

}

870

871

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

872

__attribute__((nonnull, warn_unused_result))

873

static bool add_delete_local_route(const bool add,

874

const char *address,

875

AvahiIfIndex if_index){

876

int ret;

877

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

878

char add_arg[] = "add";

879

char delete_arg[] = "delete";

880

char debug_flag[] = "--debug";

881

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

882

if(pluginhelperdir == NULL){

883

if(debug){

884

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

885

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

886

}

887

return false;

888

}

889

890

char interface[IF_NAMESIZE];

891

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

892

perror_plus("if_indextoname");

893

return false;

894

}

895

896

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

897

if(devnull == -1){

898

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

899

return false;

900

}

901

pid_t pid = fork();

902

if(pid == 0){

903

/* Child */

904

/* Raise privileges */

905

errno = raise_privileges_permanently();

906

if(errno != 0){

907

perror_plus("Failed to raise privileges");

908

/* _exit(EX_NOPERM); */

909

} else {

910

/* Set group */

911

errno = 0;

912

ret = setgid(0);

913

if(ret == -1){

914

perror_plus("setgid");

915

_exit(EX_NOPERM);

916

}

917

/* Reset supplementary groups */

918

errno = 0;

919

ret = setgroups(0, NULL);

920

if(ret == -1){

921

perror_plus("setgroups");

922

_exit(EX_NOPERM);

923

}

924

}

925

ret = dup2(devnull, STDIN_FILENO);

926

if(ret == -1){

927

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

928

_exit(EX_OSERR);

929

}

930

ret = close(devnull);

931

if(ret == -1){

932

perror_plus("close");

933

_exit(EX_OSERR);

934

}

935

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

936

if(ret == -1){

937

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

938

_exit(EX_OSERR);

939

}

940

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

941

O_RDONLY

942

| O_DIRECTORY

943

| O_PATH

944

| O_CLOEXEC));

945

if(helperdir_fd == -1){

946

perror_plus("open");

947

_exit(EX_UNAVAILABLE);

948

}

949

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

950

helper, O_RDONLY));

951

if(helper_fd == -1){

952

perror_plus("openat");

953

close(helperdir_fd);

954

_exit(EX_UNAVAILABLE);

955

}

956

close(helperdir_fd);

957

#ifdef __GNUC__

958

#pragma GCC diagnostic push

959

#pragma GCC diagnostic ignored "-Wcast-qual"

960

#endif

961

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

962

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

963

interface, debug ? debug_flag : NULL, NULL },

964

environ) == -1){

965

#ifdef __GNUC__

966

#pragma GCC diagnostic pop

967

#endif

968

perror_plus("fexecve");

969

_exit(EXIT_FAILURE);

970

}

971

}

972

if(pid == -1){

973

perror_plus("fork");

974

return false;

975

}

976

int status;

977

pid_t pret = -1;

978

errno = 0;

979

do {

980

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

981

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

982

int errno_raising = 0;

983

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

984

errno_raising = errno;

985

perror_plus("Failed to raise privileges in order to"

986

" kill helper program");

987

}

988

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

989

perror_plus("kill");

990

}

991

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

992

perror_plus("Failed to lower privileges after killing"

993

" helper program");

994

}

995

return false;

996

}

997

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

998

if(pret == -1){

999

perror_plus("waitpid");

1000

return false;

1001

}

1002

if(WIFEXITED(status)){

1003

if(WEXITSTATUS(status) != 0){

1004

fprintf_plus(stderr, "Error: iprouteadddel exited"

1005

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

1006

return false;

1007

}

1008

return true;

1009

}

1010

if(WIFSIGNALED(status)){

1011

fprintf_plus(stderr, "Error: iprouteadddel died by"

1012

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

1013

return false;

1014

}

1015

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

1016

return false;

1017

}

1018

1019

__attribute__((nonnull, warn_unused_result))

1020

static bool add_local_route(const char *address,

1021

AvahiIfIndex if_index){

1022

if(debug){

1023

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

1024

}

1025

return add_delete_local_route(true, address, if_index);

1026

}

1027

1028

__attribute__((nonnull, warn_unused_result))

1029

static bool delete_local_route(const char *address,

1030

AvahiIfIndex if_index){

1031

if(debug){

1032

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

1033

}

1034

return add_delete_local_route(false, address, if_index);

1035

}

1036

617

1037

/* Called when a Mandos server is found */

618

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

1038

__attribute__((nonnull, warn_unused_result))

1039

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

619

1040

AvahiIfIndex if_index,

620

int af){

1041

int af, mandos_context *mc){

621

1042

int ret, tcp_sd = -1;

622

1043

ssize_t sret;

623

union {

624

struct sockaddr_in in;

625

struct sockaddr_in6 in6;

626

} to;

1044

struct sockaddr_storage to;

627

1045

char *buffer = NULL;

628

1046

char *decrypted_buffer = NULL;

629

1047

size_t buffer_length = 0;

632

1050

int retval = -1;

633

1051

gnutls_session_t session;

634

1052

int pf; /* Protocol family */

1053

bool route_added = false;

635

1054

636

1055

errno = 0;

637

1056

653

1072

return -1;

654

1073

}

655

1074

656

ret = init_gnutls_session(&session);

1075

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

1076

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

1077

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

1078

bool match = false;

1079

{

1080

char *interface = NULL;

1081

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

1082

interface))){

1083

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

1084

match = true;

1085

break;

1086

}

1087

}

1088

}

1089

if(not match){

1090

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

1091

connect to the server */

1092

if(debug){

1093

char interface[IF_NAMESIZE];

1094

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

1095

perror_plus("if_indextoname");

1096

} else {

1097

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

1098

" \"%s\"\n",

1099

if_indextoname((unsigned int)if_index,

1100

interface));

1101

}

1102

}

1103

return -1;

1104

}

1105

}

1106

1107

ret = init_gnutls_session(&session, mc);

657

1108

if(ret != 0){

658

1109

return -1;

659

1110

}

660

1111

661

1112

if(debug){

662

1113

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

663

PRIu16 "\n", ip, port);

1114

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

664

1115

}

665

1116

666

tcp_sd = socket(pf, SOCK_STREAM, 0);

1117

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

667

1118

if(tcp_sd < 0){

668

1119

int e = errno;

669

1120

perror_plus("socket");

676

1127

goto mandos_end;

677

1128

}

678

1129

679

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

680

1130

if(af == AF_INET6){

681

to.in6.sin6_family = (sa_family_t)af;

682

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

1131

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

1132

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

1133

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

683

1134

} else { /* IPv4 */

684

to.in.sin_family = (sa_family_t)af;

685

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

1135

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

1136

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

1137

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

686

1138

}

687

1139

if(ret < 0 ){

688

1140

int e = errno;

697

1149

goto mandos_end;

698

1150

}

699

1151

if(af == AF_INET6){

700

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

701

-Wconversion and

702

-Wunreachable-code */

703

704

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

705

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

706

-Wunreachable-code*/

1152

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

1153

if(IN6_IS_ADDR_LINKLOCAL

1154

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

707

1155

if(if_index == AVAHI_IF_UNSPEC){

708

1156

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

709

1157

" incomplete without a network interface\n");

711

1159

goto mandos_end;

712

1160

}

713

1161

/* Set the network interface number as scope */

714

to.in6.sin6_scope_id = (uint32_t)if_index;

1162

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

715

1163

}

716

1164

} else {

717

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

718

-Wconversion and

719

-Wunreachable-code */

1165

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

720

1166

}

721

1167

722

1168

if(quit_now){

730

1176

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

731

1177

perror_plus("if_indextoname");

732

1178

} else {

733

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

734

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

1179

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

1180

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

735

1181

}

736

1182

} else {

737

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

738

ip, port);

1183

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

1184

ip, (uintmax_t)port);

739

1185

}

740

1186

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

741

1187

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

742

const char *pcret;

743

if(af == AF_INET6){

744

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

745

sizeof(addrstr));

746

} else {

747

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

748

sizeof(addrstr));

749

}

750

if(pcret == NULL){

751

perror_plus("inet_ntop");

752

} else {

753

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

754

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

755

}

756

}

757

}

758

759

if(quit_now){

760

errno = EINTR;

761

goto mandos_end;

762

}

763

764

if(af == AF_INET6){

765

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

766

} else {

767

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

768

}

769

if(ret < 0){

770

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

771

int e = errno;

772

perror_plus("connect");

773

errno = e;

774

}

775

goto mandos_end;

776

}

777

778

if(quit_now){

779

errno = EINTR;

780

goto mandos_end;

1188

if(af == AF_INET6){

1189

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

1190

sizeof(struct sockaddr_in6),

1191

addrstr, sizeof(addrstr), NULL, 0,

1192

NI_NUMERICHOST);

1193

} else {

1194

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

1195

sizeof(struct sockaddr_in),

1196

addrstr, sizeof(addrstr), NULL, 0,

1197

NI_NUMERICHOST);

1198

}

1199

if(ret == EAI_SYSTEM){

1200

perror_plus("getnameinfo");

1201

} else if(ret != 0) {

1202

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

1203

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

1204

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

1205

}

1206

}

1207

1208

if(quit_now){

1209

errno = EINTR;

1210

goto mandos_end;

1211

}

1212

1213

while(true){

1214

if(af == AF_INET6){

1215

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

1216

sizeof(struct sockaddr_in6));

1217

} else {

1218

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

1219

sizeof(struct sockaddr_in));

1220

}

1221

if(ret < 0){

1222

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

1223

and if_index != AVAHI_IF_UNSPEC

1224

and connect_to == NULL

1225

and not route_added and

1226

((af == AF_INET6 and not

1227

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1228

&to)->sin6_addr)))

1229

or (af == AF_INET and

1230

/* Not a a IPv4LL address */

1231

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

1232

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

1233

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

1234

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

1235

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

1236

connect to a Mandos server announced by Avahi on a server

1237

host with a global address. Work around this by retrying

1238

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

1239

1240

Avahi bug reference:

1241

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

1242

https://bugs.debian.org/587961

1243

*/

1244

if(debug){

1245

fprintf_plus(stderr, "Mandos server unreachable, trying"

1246

" direct route\n");

1247

}

1248

int e = errno;

1249

route_added = add_local_route(ip, if_index);

1250

if(route_added){

1251

continue;

1252

}

1253

errno = e;

1254

}

1255

if(errno != ECONNREFUSED or debug){

1256

int e = errno;

1257

perror_plus("connect");

1258

errno = e;

1259

}

1260

goto mandos_end;

1261

}

1262

1263

if(quit_now){

1264

errno = EINTR;

1265

goto mandos_end;

1266

}

1267

break;

781

1268

}

782

1269

783

1270

const char *out = mandos_protocol_version;

819

1306

goto mandos_end;

820

1307

}

821

1308

822

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

823

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1309

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

1310

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

1311

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

1312

gnutls_transport_set_ptr(session,

1313

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

824

1314

825

1315

if(quit_now){

826

1316

errno = EINTR;

931

1421

if(buffer_length > 0){

932

1422

ssize_t decrypted_buffer_size;

933

1423

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

934

&decrypted_buffer);

1424

&decrypted_buffer, mc);

935

1425

if(decrypted_buffer_size >= 0){

936

1426

1427

clearerr(stdout);

937

1428

written = 0;

938

1429

while(written < (size_t) decrypted_buffer_size){

939

1430

if(quit_now){

955

1446

}

956

1447

written += (size_t)ret;

957

1448

}

1449

ret = fflush(stdout);

1450

if(ret != 0){

1451

int e = errno;

1452

if(debug){

1453

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

1454

strerror(errno));

1455

}

1456

errno = e;

1457

goto mandos_end;

1458

}

958

1459

retval = 0;

959

1460

}

960

1461

}

963

1464

964

1465

mandos_end:

965

1466

{

1467

if(route_added){

1468

if(not delete_local_route(ip, if_index)){

1469

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

1470

" interface %d", ip, if_index);

1471

}

1472

}

966

1473

int e = errno;

967

1474

free(decrypted_buffer);

968

1475

free(buffer);

969

1476

if(tcp_sd >= 0){

970

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

1477

ret = close(tcp_sd);

971

1478

}

972

1479

if(ret == -1){

973

1480

if(e == 0){

985

1492

return retval;

986

1493

}

987

1494

1495

__attribute__((nonnull))

988

1496

static void resolve_callback(AvahiSServiceResolver *r,

989

1497

AvahiIfIndex interface,

990

1498

AvahiProtocol proto,

998

1506

AVAHI_GCC_UNUSED AvahiStringList *txt,

999

1507

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1000

1508

flags,

1001

AVAHI_GCC_UNUSED void* userdata){

1002

assert(r);

1509

void *mc){

1510

if(r == NULL){

1511

return;

1512

}

1003

1513

1004

1514

/* Called whenever a service has been resolved successfully or

1005

1515

timed out */

1006

1516

1007

1517

if(quit_now){

1518

avahi_s_service_resolver_free(r);

1008

1519

return;

1009

1520

}

1010

1521

1014

1525

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

1015

1526

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

1016

1527

domain,

1017

avahi_strerror(avahi_server_errno(mc.server)));

1528

avahi_strerror(avahi_server_errno

1529

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

1018

1530

break;

1019

1531

1020

1532

case AVAHI_RESOLVER_FOUND:

1026

1538

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

1027

1539

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

1028

1540

}

1029

int ret = start_mandos_communication(ip, port, interface,

1030

avahi_proto_to_af(proto));

1541

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

1542

interface,

1543

avahi_proto_to_af(proto),

1544

mc);

1031

1545

if(ret == 0){

1032

avahi_simple_poll_quit(mc.simple_poll);

1546

avahi_simple_poll_quit(simple_poll);

1033

1547

} else {

1034

if(not add_server(ip, port, interface,

1035

avahi_proto_to_af(proto))){

1548

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

1549

avahi_proto_to_af(proto),

1550

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

1036

1551

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

1037

1552

" list\n", name);

1038

1553

}

1051

1566

const char *domain,

1052

1567

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1053

1568

flags,

1054

AVAHI_GCC_UNUSED void* userdata){

1055

assert(b);

1569

void *mc){

1570

if(b == NULL){

1571

return;

1572

}

1056

1573

1057

1574

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

1058

1575

is removed from the LAN */

1066

1583

case AVAHI_BROWSER_FAILURE:

1067

1584

1068

1585

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

1069

avahi_strerror(avahi_server_errno(mc.server)));

1070

avahi_simple_poll_quit(mc.simple_poll);

1586

avahi_strerror(avahi_server_errno

1587

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

1588

avahi_simple_poll_quit(simple_poll);

1071

1589

return;

1072

1590

1073

1591

case AVAHI_BROWSER_NEW:

1076

1594

the callback function is called the Avahi server will free the

1077

1595

resolver for us. */

1078

1596

1079

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

1080

name, type, domain, protocol, 0,

1081

resolve_callback, NULL) == NULL)

1597

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

1598

interface, protocol, name, type,

1599

domain, protocol, 0,

1600

resolve_callback, mc) == NULL)

1082

1601

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

1083

1602

" %s\n", name,

1084

avahi_strerror(avahi_server_errno(mc.server)));

1603

avahi_strerror(avahi_server_errno

1604

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

1085

1605

break;

1086

1606

1087

1607

case AVAHI_BROWSER_REMOVE:

1106

1626

signal_received = sig;

1107

1627

int old_errno = errno;

1108

1628

/* set main loop to exit */

1109

if(mc.simple_poll != NULL){

1110

avahi_simple_poll_quit(mc.simple_poll);

1629

if(simple_poll != NULL){

1630

avahi_simple_poll_quit(simple_poll);

1111

1631

}

1112

1632

errno = old_errno;

1113

1633

}

1114

1634

1635

__attribute__((nonnull, warn_unused_result))

1115

1636

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

1116

1637

int ret;

1638

int old_errno;

1117

1639

1118

1640

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

1119

1641

if(s < 0){

1642

old_errno = errno;

1120

1643

perror_plus("socket");

1644

errno = old_errno;

1121

1645

return false;

1122

1646

}

1123

strcpy(ifr->ifr_name, ifname);

1647

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

1648

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

1124

1649

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1125

1650

if(ret == -1){

1126

1651

if(debug){

1652

old_errno = errno;

1127

1653

perror_plus("ioctl SIOCGIFFLAGS");

1654

errno = old_errno;

1128

1655

}

1129

1656

return false;

1130

1657

}

1131

1658

return true;

1132

1659

}

1133

1660

1661

__attribute__((nonnull, warn_unused_result))

1134

1662

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

1135

1663

1136

1664

/* Reject the loopback device */

1178

1706

* corresponds to an acceptable network device.

1179

1707

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

1180

1708

*/

1709

__attribute__((nonnull, warn_unused_result))

1181

1710

int good_interface(const struct dirent *if_entry){

1182

1711

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

1183

1712

return 0;

1199

1728

}

1200

1729

1201

1730

/*

1202

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

1203

* corresponds to an acceptable network device which is up.

1204

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

1205

*/

1206

int up_interface(const struct dirent *if_entry){

1207

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

1208

return 0;

1209

}

1210

1211

struct ifreq ifr;

1212

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

1213

if(debug){

1214

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

1215

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

1216

}

1217

return 0;

1218

}

1219

1220

/* Reject down interfaces */

1221

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

1222

if(debug){

1223

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

1224

if_entry->d_name);

1225

}

1226

return 0;

1227

}

1228

1229

/* Reject non-running interfaces */

1230

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

1231

if(debug){

1232

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

1233

if_entry->d_name);

1234

}

1235

return 0;

1236

}

1237

1238

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

1239

return 0;

1240

}

1241

return 1;

1242

}

1243

1731

* This function determines if a network interface is up.

1732

*/

1733

__attribute__((nonnull, warn_unused_result))

1734

bool interface_is_up(const char *interface){

1735

struct ifreq ifr;

1736

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

1737

if(debug){

1738

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

1739

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

1740

}

1741

return false;

1742

}

1743

1744

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

1745

}

1746

1747

/*

1748

* This function determines if a network interface is running

1749

*/

1750

__attribute__((nonnull, warn_unused_result))

1751

bool interface_is_running(const char *interface){

1752

struct ifreq ifr;

1753

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

1754

if(debug){

1755

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

1756

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

1757

}

1758

return false;

1759

}

1760

1761

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

1762

}

1763

1764

__attribute__((nonnull, pure, warn_unused_result))

1244

1765

int notdotentries(const struct dirent *direntry){

1245

1766

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

1246

1767

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

1253

1774

}

1254

1775

1255

1776

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

1777

__attribute__((nonnull, warn_unused_result))

1256

1778

int runnable_hook(const struct dirent *direntry){

1257

1779

int ret;

1258

1780

size_t sret;

1266

1788

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

1267

1789

"abcdefghijklmnopqrstuvwxyz"

1268

1790

"0123456789"

1269

"_-");

1791

"_.-");

1270

1792

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

1271

1793

/* Contains non-allowed characters */

1272

1794

if(debug){

1276

1798

return 0;

1277

1799

}

1278

1800

1279

char *fullname = NULL;

1280

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

1281

if(ret < 0){

1282

perror_plus("asprintf");

1283

return 0;

1284

}

1285

1286

ret = stat(fullname, &st);

1801

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

1287

1802

if(ret == -1){

1288

1803

if(debug){

1289

1804

perror_plus("Could not stat hook");

1313

1828

return 1;

1314

1829

}

1315

1830

1316

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1831

__attribute__((nonnull, warn_unused_result))

1832

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1833

mandos_context *mc){

1317

1834

int ret;

1318

1835

struct timespec now;

1319

1836

struct timespec waited_time;

1320

1837

intmax_t block_time;

1321

1838

1322

1839

while(true){

1323

if(mc.current_server == NULL){

1324

if (debug){

1840

if(mc->current_server == NULL){

1841

if(debug){

1325

1842

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

1326

1843

" No timeout!\n");

1327

1844

}

1328

1845

ret = avahi_simple_poll_iterate(s, -1);

1329

1846

} else {

1330

if (debug){

1847

if(debug){

1331

1848

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

1332

1849

" it, or wait\n");

1333

1850

}

1340

1857

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

1341

1858

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

1342

1859

waited_time.tv_sec = (now.tv_sec

1343

- mc.current_server->last_seen.tv_sec);

1860

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

1344

1861

waited_time.tv_nsec = (now.tv_nsec

1345

- mc.current_server->last_seen.tv_nsec);

1862

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

1346

1863

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

1347

1864

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

1348

1865

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

1350

1867

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

1351

1868

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

1352

1869

1353

if (debug){

1870

if(debug){

1354

1871

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

1355

1872

block_time);

1356

1873

}

1357

1874

1358

1875

if(block_time <= 0){

1359

ret = start_mandos_communication(mc.current_server->ip,

1360

mc.current_server->port,

1361

mc.current_server->if_index,

1362

mc.current_server->af);

1876

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

1877

mc->current_server->port,

1878

mc->current_server->if_index,

1879

mc->current_server->af, mc);

1363

1880

if(ret == 0){

1364

avahi_simple_poll_quit(mc.simple_poll);

1881

avahi_simple_poll_quit(s);

1365

1882

return 0;

1366

1883

}

1367

1884

ret = clock_gettime(CLOCK_MONOTONIC,

1368

&mc.current_server->last_seen);

1885

&mc->current_server->last_seen);

1369

1886

if(ret == -1){

1370

1887

perror_plus("clock_gettime");

1371

1888

return -1;

1372

1889

}

1373

mc.current_server = mc.current_server->next;

1890

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

1374

1891

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

1375

1892

servers, but don't block */

1376

1893

}

1378

1895

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

1379

1896

}

1380

1897

if(ret != 0){

1381

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

1898

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

1382

1899

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

1383

1900

}

1384

1901

}

1385

1902

}

1386

1903

}

1387

1904

1388

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

1905

__attribute__((nonnull))

1906

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

1389

1907

const float delay){

1390

struct dirent **direntries;

1391

struct dirent *direntry;

1392

int ret;

1393

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

1394

alphasort);

1908

struct dirent **direntries = NULL;

1909

if(hookdir_fd == -1){

1910

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1911

| O_CLOEXEC);

1912

if(hookdir_fd == -1){

1913

if(errno == ENOENT){

1914

if(debug){

1915

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

1916

" found\n", hookdir);

1917

}

1918

} else {

1919

perror_plus("open");

1920

}

1921

return;

1922

}

1923

}

1924

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

1925

runnable_hook, alphasort);

1395

1926

if(numhooks == -1){

1396

1927

perror_plus("scandir");

1397

} else {

1398

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

1399

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

1400

direntry = direntries[i];

1401

char *fullname = NULL;

1402

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

1403

if(ret < 0){

1928

return;

1929

}

1930

struct dirent *direntry;

1931

int ret;

1932

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

1933

if(devnull == -1){

1934

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

1935

return;

1936

}

1937

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

1938

direntry = direntries[i];

1939

if(debug){

1940

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

1941

direntry->d_name);

1942

}

1943

pid_t hook_pid = fork();

1944

if(hook_pid == 0){

1945

/* Child */

1946

/* Raise privileges */

1947

errno = raise_privileges_permanently();

1948

if(errno != 0){

1949

perror_plus("Failed to raise privileges");

1950

_exit(EX_NOPERM);

1951

}

1952

/* Set group */

1953

errno = 0;

1954

ret = setgid(0);

1955

if(ret == -1){

1956

perror_plus("setgid");

1957

_exit(EX_NOPERM);

1958

}

1959

/* Reset supplementary groups */

1960

errno = 0;

1961

ret = setgroups(0, NULL);

1962

if(ret == -1){

1963

perror_plus("setgroups");

1964

_exit(EX_NOPERM);

1965

}

1966

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

1967

if(ret == -1){

1968

perror_plus("setenv");

1969

_exit(EX_OSERR);

1970

}

1971

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

1972

if(ret == -1){

1973

perror_plus("setenv");

1974

_exit(EX_OSERR);

1975

}

1976

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

1977

if(ret == -1){

1978

perror_plus("setenv");

1979

_exit(EX_OSERR);

1980

}

1981

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

1982

if(ret == -1){

1983

perror_plus("setenv");

1984

_exit(EX_OSERR);

1985

}

1986

char *delaystring;

1987

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

1988

if(ret == -1){

1404

1989

perror_plus("asprintf");

1405

continue;

1406

}

1407

if(debug){

1408

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

1409

direntry->d_name);

1410

}

1411

pid_t hook_pid = fork();

1412

if(hook_pid == 0){

1413

/* Child */

1414

/* Raise privileges */

1415

errno = 0;

1416

ret = seteuid(0);

1417

if(ret == -1){

1418

perror_plus("seteuid");

1419

}

1420

/* Raise privileges even more */

1421

errno = 0;

1422

ret = setuid(0);

1423

if(ret == -1){

1424

perror_plus("setuid");

1425

}

1426

/* Set group */

1427

errno = 0;

1428

ret = setgid(0);

1429

if(ret == -1){

1430

perror_plus("setgid");

1431

}

1432

/* Reset supplementary groups */

1433

errno = 0;

1434

ret = setgroups(0, NULL);

1435

if(ret == -1){

1436

perror_plus("setgroups");

1437

}

1438

dup2(devnull, STDIN_FILENO);

1439

close(devnull);

1440

dup2(STDERR_FILENO, STDOUT_FILENO);

1441

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

1442

if(ret == -1){

1443

perror_plus("setenv");

1444

_exit(EX_OSERR);

1445

}

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

char *delaystring;

1462

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

1463

if(ret == -1){

1464

perror_plus("asprintf");

1465

_exit(EX_OSERR);

1466

}

1467

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

1468

if(ret == -1){

1469

free(delaystring);

1470

perror_plus("setenv");

1471

_exit(EX_OSERR);

1472

}

1990

_exit(EX_OSERR);

1991

}

1992

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

1993

if(ret == -1){

1473

1994

free(delaystring);

1474

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

1475

perror_plus("execl");

1476

_exit(EXIT_FAILURE);

1477

}

1478

} else {

1479

int status;

1480

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

1481

perror_plus("waitpid");

1482

free(fullname);

1483

continue;

1484

}

1485

if(WIFEXITED(status)){

1486

if(WEXITSTATUS(status) != 0){

1487

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

1488

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

1489

WEXITSTATUS(status));

1490

free(fullname);

1491

continue;

1492

}

1493

} else if(WIFSIGNALED(status)){

1494

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

1495

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

1496

WTERMSIG(status));

1497

free(fullname);

1498

continue;

1499

} else {

1500

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

1501

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

1502

free(fullname);

1503

continue;

1504

}

1505

}

1506

free(fullname);

1507

if(debug){

1508

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

1509

direntry->d_name);

1510

}

1511

}

1512

close(devnull);

1513

}

1514

return true;

1995

perror_plus("setenv");

1996

_exit(EX_OSERR);

1997

}

1998

free(delaystring);

1999

if(connect_to != NULL){

2000

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

2001

if(ret == -1){

2002

perror_plus("setenv");

2003

_exit(EX_OSERR);

2004

}

2005

}

2006

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

2007

direntry->d_name,

2008

O_RDONLY));

2009

if(hook_fd == -1){

2010

perror_plus("openat");

2011

_exit(EXIT_FAILURE);

2012

}

2013

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

2014

perror_plus("close");

2015

_exit(EXIT_FAILURE);

2016

}

2017

ret = dup2(devnull, STDIN_FILENO);

2018

if(ret == -1){

2019

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

2020

_exit(EX_OSERR);

2021

}

2022

ret = close(devnull);

2023

if(ret == -1){

2024

perror_plus("close");

2025

_exit(EX_OSERR);

2026

}

2027

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2028

if(ret == -1){

2029

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

2030

_exit(EX_OSERR);

2031

}

2032

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

2033

environ) == -1){

2034

perror_plus("fexecve");

2035

_exit(EXIT_FAILURE);

2036

}

2037

} else {

2038

if(hook_pid == -1){

2039

perror_plus("fork");

2040

free(direntry);

2041

continue;

2042

}

2043

int status;

2044

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

2045

perror_plus("waitpid");

2046

free(direntry);

2047

continue;

2048

}

2049

if(WIFEXITED(status)){

2050

if(WEXITSTATUS(status) != 0){

2051

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

2052

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

2053

WEXITSTATUS(status));

2054

free(direntry);

2055

continue;

2056

}

2057

} else if(WIFSIGNALED(status)){

2058

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

2059

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

2060

WTERMSIG(status));

2061

free(direntry);

2062

continue;

2063

} else {

2064

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

2065

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

2066

free(direntry);

2067

continue;

2068

}

2069

}

2070

if(debug){

2071

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

2072

direntry->d_name);

2073

}

2074

free(direntry);

2075

}

2076

free(direntries);

2077

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

2078

perror_plus("close");

2079

} else {

2080

hookdir_fd = -1;

2081

}

2082

close(devnull);

2083

}

2084

2085

__attribute__((nonnull, warn_unused_result))

2086

int bring_up_interface(const char *const interface,

2087

const float delay){

2088

int old_errno = errno;

2089

int ret;

2090

struct ifreq network;

2091

unsigned int if_index = if_nametoindex(interface);

2092

if(if_index == 0){

2093

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

2094

errno = old_errno;

2095

return ENXIO;

2096

}

2097

2098

if(quit_now){

2099

errno = old_errno;

2100

return EINTR;

2101

}

2102

2103

if(not interface_is_up(interface)){

2104

int ret_errno = 0;

2105

int ioctl_errno = 0;

2106

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

2107

ret_errno = errno;

2108

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

2109

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

2110

errno = old_errno;

2111

return ret_errno;

2112

}

2113

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

2114

2115

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

2116

if(sd == -1){

2117

ret_errno = errno;

2118

perror_plus("socket");

2119

errno = old_errno;

2120

return ret_errno;

2121

}

2122

2123

if(quit_now){

2124

ret = close(sd);

2125

if(ret == -1){

2126

perror_plus("close");

2127

}

2128

errno = old_errno;

2129

return EINTR;

2130

}

2131

2132

if(debug){

2133

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

2134

interface);

2135

}

2136

2137

/* Raise privileges */

2138

ret_errno = raise_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to raise privileges");

2142

}

2143

2144

#ifdef __linux__

2145

int ret_linux;

2146

bool restore_loglevel = false;

2147

if(ret_errno == 0){

2148

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2149

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

2150

ret_linux = klogctl(8, NULL, 5);

2151

if(ret_linux == -1){

2152

perror_plus("klogctl");

2153

} else {

2154

restore_loglevel = true;

2155

}

2156

}

2157

#endif /* __linux__ */

2158

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

2159

ioctl_errno = errno;

2160

#ifdef __linux__

2161

if(restore_loglevel){

2162

ret_linux = klogctl(7, NULL, 0);

2163

if(ret_linux == -1){

2164

perror_plus("klogctl");

2165

}

2166

}

2167

#endif /* __linux__ */

2168

2169

/* If raise_privileges() succeeded above */

2170

if(ret_errno == 0){

2171

/* Lower privileges */

2172

ret_errno = lower_privileges();

2173

if(ret_errno != 0){

2174

errno = ret_errno;

2175

perror_plus("Failed to lower privileges");

2176

}

2177

}

2178

2179

/* Close the socket */

2180

ret = close(sd);

2181

if(ret == -1){

2182

perror_plus("close");

2183

}

2184

2185

if(ret_setflags == -1){

2186

errno = ioctl_errno;

2187

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2188

errno = old_errno;

2189

return ioctl_errno;

2190

}

2191

} else if(debug){

2192

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

2193

interface);

2194

}

2195

2196

/* Sleep checking until interface is running.

2197

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

2198

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

2199

if(interface_is_running(interface)){

2200

break;

2201

}

2202

struct timespec sleeptime = { .tv_nsec = 250000000 };

2203

ret = nanosleep(&sleeptime, NULL);

2204

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

2205

perror_plus("nanosleep");

2206

}

2207

}

2208

2209

errno = old_errno;

2210

return 0;

2211

}

2212

2213

__attribute__((nonnull, warn_unused_result))

2214

int take_down_interface(const char *const interface){

2215

int old_errno = errno;

2216

struct ifreq network;

2217

unsigned int if_index = if_nametoindex(interface);

2218

if(if_index == 0){

2219

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

2220

errno = old_errno;

2221

return ENXIO;

2222

}

2223

if(interface_is_up(interface)){

2224

int ret_errno = 0;

2225

int ioctl_errno = 0;

2226

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

2227

ret_errno = errno;

2228

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

2229

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

2230

errno = old_errno;

2231

return ret_errno;

2232

}

2233

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

2234

2235

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

2236

if(sd == -1){

2237

ret_errno = errno;

2238

perror_plus("socket");

2239

errno = old_errno;

2240

return ret_errno;

2241

}

2242

2243

if(debug){

2244

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

2245

interface);

2246

}

2247

2248

/* Raise privileges */

2249

ret_errno = raise_privileges();

2250

if(ret_errno != 0){

2251

errno = ret_errno;

2252

perror_plus("Failed to raise privileges");

2253

}

2254

2255

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

2256

ioctl_errno = errno;

2257

2258

/* If raise_privileges() succeeded above */

2259

if(ret_errno == 0){

2260

/* Lower privileges */

2261

ret_errno = lower_privileges();

2262

if(ret_errno != 0){

2263

errno = ret_errno;

2264

perror_plus("Failed to lower privileges");

2265

}

2266

}

2267

2268

/* Close the socket */

2269

int ret = close(sd);

2270

if(ret == -1){

2271

perror_plus("close");

2272

}

2273

2274

if(ret_setflags == -1){

2275

errno = ioctl_errno;

2276

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2277

errno = old_errno;

2278

return ioctl_errno;

2279

}

2280

} else if(debug){

2281

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

2282

interface);

2283

}

2284

2285

errno = old_errno;

2286

return 0;

1515

2287

}

1516

2288

1517

2289

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

2290

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

2291

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

2292

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

2293

.current_server = NULL, .interfaces = NULL,

2294

.interfaces_size = 0 };

1518

2295

AvahiSServiceBrowser *sb = NULL;

1519

int error;

2296

error_t ret_errno;

1520

2297

int ret;

1521

2298

intmax_t tmpmax;

1522

2299

char *tmp;

1523

2300

int exitcode = EXIT_SUCCESS;

1524

const char *interface = "";

1525

struct ifreq network;

1526

int sd = -1;

1527

bool take_down_interface = false;

1528

uid_t uid;

1529

gid_t gid;

1530

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

1531

bool tempdir_created = false;

2301

char *interfaces_to_take_down = NULL;

2302

size_t interfaces_to_take_down_size = 0;

2303

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

2304

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

2305

char *tempdir = NULL;

1532

2306

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1533

2307

const char *seckey = PATHDIR "/" SECKEY;

1534

2308

const char *pubkey = PATHDIR "/" PUBKEY;

2309

const char *dh_params_file = NULL;

2310

char *interfaces_hooks = NULL;

1535

2311

1536

2312

bool gnutls_initialized = false;

1537

2313

bool gpgme_initialized = false;

1589

2365

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

1590

2366

" Diffie-Hellman key exchange",

1591

2367

.group = 2 },

2368

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

2369

.arg = "FILE",

2370

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

2371

" for the Diffie-Hellman key exchange",

2372

.group = 2 },

1592

2373

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

1593

2374

.arg = "STRING",

1594

2375

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

1599

2380

.group = 2 },

1600

2381

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

1601

2382

.arg = "SECONDS",

1602

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

2383

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

1603

2384

.group = 2 },

1604

2385

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

1605

2386

.arg = "DIR",

1628

2409

connect_to = arg;

1629

2410

break;

1630

2411

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

1631

interface = arg;

2412

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

2413

arg, (int)',');

2414

if(ret_errno != 0){

2415

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

2416

}

1632

2417

break;

1633

2418

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

1634

2419

seckey = arg;

1645

2430

}

1646

2431

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

1647

2432

break;

2433

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

2434

dh_params_file = arg;

2435

break;

1648

2436

case 130: /* --priority */

1649

2437

mc.priority = arg;

1650

2438

break;

1690

2478

.args_doc = "",

1691

2479

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

1692

2480

" passwords from a Mandos server" };

1693

ret = argp_parse(&argp, argc, argv,

1694

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1695

switch(ret){

2481

ret_errno = argp_parse(&argp, argc, argv,

2482

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2483

switch(ret_errno){

1696

2484

case 0:

1697

2485

break;

1698

2486

case ENOMEM:

1699

2487

default:

1700

errno = ret;

2488

errno = ret_errno;

1701

2489

perror_plus("argp_parse");

1702

2490

exitcode = EX_OSERR;

1703

2491

goto end;

1706

2494

goto end;

1707

2495

}

1708

2496

}

1709

2497

1710

2498

{

1711

2499

/* Work around Debian bug #633582:

1712

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

2500

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

1713

2501

1714

/* Re-raise priviliges */

1715

errno = 0;

1716

ret = seteuid(0);

1717

if(ret == -1){

1718

perror_plus("seteuid");

2502

/* Re-raise privileges */

2503

ret = raise_privileges();

2504

if(ret != 0){

2505

errno = ret;

2506

perror_plus("Failed to raise privileges");

1719

2507

} else {

1720

2508

struct stat st;

1721

2509

1736

2524

}

1737

2525

}

1738

2526

}

1739

TEMP_FAILURE_RETRY(close(seckey_fd));

2527

close(seckey_fd);

1740

2528

}

1741

2529

}

1742

2530

1743

2531

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

1744

2532

int pubkey_fd = open(pubkey, O_RDONLY);

1745

2533

if(pubkey_fd == -1){

1757

2545

}

1758

2546

}

1759

2547

}

1760

TEMP_FAILURE_RETRY(close(pubkey_fd));

1761

}

1762

}

1763

2548

close(pubkey_fd);

2549

}

2550

}

2551

2552

if(dh_params_file != NULL

2553

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

2554

int dhparams_fd = open(dh_params_file, O_RDONLY);

2555

if(dhparams_fd == -1){

2556

perror_plus("open");

2557

} else {

2558

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

2559

if(ret == -1){

2560

perror_plus("fstat");

2561

} else {

2562

if(S_ISREG(st.st_mode)

2563

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

2564

ret = fchown(dhparams_fd, uid, gid);

2565

if(ret == -1){

2566

perror_plus("fchown");

2567

}

2568

}

2569

}

2570

close(dhparams_fd);

2571

}

2572

}

2573

1764

2574

/* Lower privileges */

1765

errno = 0;

1766

ret = seteuid(uid);

1767

if(ret == -1){

1768

perror_plus("seteuid");

2575

ret = lower_privileges();

2576

if(ret != 0){

2577

errno = ret;

2578

perror_plus("Failed to lower privileges");

2579

}

2580

}

2581

}

2582

2583

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

2584

{

2585

char *interface = NULL;

2586

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

2587

interface))){

2588

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

2589

and if_nametoindex(interface) == 0){

2590

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

2591

fprintf_plus(stderr, "Not using nonexisting interface"

2592

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

2593

}

2594

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

2595

interface = NULL;

1769

2596

}

1770

2597

}

1771

2598

}

1772

2599

1773

2600

/* Run network hooks */

1774

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

1775

goto end;

2601

{

2602

if(mc.interfaces != NULL){

2603

interfaces_hooks = malloc(mc.interfaces_size);

2604

if(interfaces_hooks == NULL){

2605

perror_plus("malloc");

2606

goto end;

2607

}

2608

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

2609

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

2610

}

2611

run_network_hooks("start", interfaces_hooks != NULL ?

2612

interfaces_hooks : "", delay);

1776

2613

}

1777

2614

1778

2615

if(not debug){

1779

2616

avahi_set_log_function(empty_log);

1780

2617

}

1781

2618

1782

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

1783

struct dirent **direntries;

1784

/* First look for interfaces that are up */

1785

ret = scandir(sys_class_net, &direntries, up_interface,

1786

alphasort);

1787

if(ret == 0){

1788

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

1789

free(direntries);

1790

ret = scandir(sys_class_net, &direntries, good_interface,

1791

alphasort);

1792

}

1793

if(ret >= 1){

1794

/* Pick the first interface returned */

1795

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

1796

if(debug){

1797

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

1798

}

1799

if(interface == NULL){

1800

perror_plus("malloc");

1801

free(direntries);

1802

exitcode = EXIT_FAILURE;

1803

goto end;

1804

}

1805

free(direntries);

1806

} else {

1807

free(direntries);

1808

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

1809

exitcode = EXIT_FAILURE;

1810

goto end;

1811

}

1812

}

1813

1814

2619

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

1815

2620

from the signal handler */

1816

2621

/* Initialize the pseudo-RNG for Avahi */

1817

2622

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

1818

mc.simple_poll = avahi_simple_poll_new();

1819

if(mc.simple_poll == NULL){

2623

simple_poll = avahi_simple_poll_new();

2624

if(simple_poll == NULL){

1820

2625

fprintf_plus(stderr,

1821

2626

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

1822

2627

exitcode = EX_UNAVAILABLE;

1886

2691

}

1887

2692

}

1888

2693

1889

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

1890

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

1891

if_index = (AvahiIfIndex) if_nametoindex(interface);

1892

if(if_index == 0){

1893

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

1894

exitcode = EX_UNAVAILABLE;

1895

goto end;

1896

}

1897

1898

if(quit_now){

1899

goto end;

1900

}

1901

1902

/* Re-raise priviliges */

1903

errno = 0;

1904

ret = seteuid(0);

1905

if(ret == -1){

1906

perror_plus("seteuid");

1907

}

1908

1909

#ifdef __linux__

1910

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1911

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

1912

ret = klogctl(8, NULL, 5);

1913

bool restore_loglevel = true;

1914

if(ret == -1){

1915

restore_loglevel = false;

1916

perror_plus("klogctl");

1917

}

1918

#endif /* __linux__ */

1919

1920

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1921

if(sd < 0){

1922

perror_plus("socket");

1923

exitcode = EX_OSERR;

1924

#ifdef __linux__

1925

if(restore_loglevel){

1926

ret = klogctl(7, NULL, 0);

1927

if(ret == -1){

1928

perror_plus("klogctl");

1929

}

1930

}

1931

#endif /* __linux__ */

1932

/* Lower privileges */

1933

errno = 0;

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

1938

goto end;

1939

}

1940

strcpy(network.ifr_name, interface);

1941

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

1942

if(ret == -1){

1943

perror_plus("ioctl SIOCGIFFLAGS");

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

1949

}

1950

}

1951

#endif /* __linux__ */

1952

exitcode = EX_OSERR;

1953

/* Lower privileges */

1954

errno = 0;

1955

ret = seteuid(uid);

1956

if(ret == -1){

1957

perror_plus("seteuid");

1958

}

1959

goto end;

1960

}

1961

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

1962

network.ifr_flags |= IFF_UP;

1963

take_down_interface = true;

1964

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

1965

if(ret == -1){

1966

take_down_interface = false;

1967

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1968

exitcode = EX_OSERR;

1969

#ifdef __linux__

1970

if(restore_loglevel){

1971

ret = klogctl(7, NULL, 0);

1972

if(ret == -1){

1973

perror_plus("klogctl");

2694

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

2695

if(mc.interfaces == NULL){

2696

struct dirent **direntries = NULL;

2697

/* Look for any good interfaces */

2698

ret = scandir(sys_class_net, &direntries, good_interface,

2699

alphasort);

2700

if(ret >= 1){

2701

/* Add all found interfaces to interfaces list */

2702

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

2703

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

2704

direntries[i]->d_name);

2705

if(ret_errno != 0){

2706

errno = ret_errno;

2707

perror_plus("argz_add");

2708

free(direntries[i]);

2709

continue;

2710

}

2711

if(debug){

2712

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

2713

direntries[i]->d_name);

2714

}

2715

free(direntries[i]);

2716

}

2717

free(direntries);

2718

} else {

2719

if(ret == 0){

2720

free(direntries);

2721

}

2722

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

2723

exitcode = EXIT_FAILURE;

2724

goto end;

2725

}

2726

}

2727

2728

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

2729

{

2730

char *interface = NULL;

2731

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

2732

interface))){

2733

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

2734

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

2735

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

2736

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

2737

interface);

2738

interface = NULL;

2739

while((interface = argz_next(mc.interfaces,

2740

mc.interfaces_size, interface))){

2741

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

2742

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

2743

interface);

2744

interface = NULL;

1974

2745

}

1975

2746

}

1976

#endif /* __linux__ */

1977

/* Lower privileges */

1978

errno = 0;

1979

ret = seteuid(uid);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

goto end;

1984

}

1985

}

1986

/* Sleep checking until interface is running.

1987

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

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCGIFFLAGS");

1992

} else if(network.ifr_flags & IFF_RUNNING){

1993

2747

break;

1994

2748

}

1995

struct timespec sleeptime = { .tv_nsec = 250000000 };

1996

ret = nanosleep(&sleeptime, NULL);

1997

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

1998

perror_plus("nanosleep");

1999

}

2000

}

2001

if(not take_down_interface){

2002

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

2003

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

2004

if(ret == -1){

2005

perror_plus("close");

2006

}

2007

}

2008

#ifdef __linux__

2009

if(restore_loglevel){

2010

/* Restores kernel loglevel to default */

2011

ret = klogctl(7, NULL, 0);

2012

if(ret == -1){

2013

perror_plus("klogctl");

2014

}

2015

}

2016

#endif /* __linux__ */

2017

/* Lower privileges */

2018

errno = 0;

2019

/* Lower privileges */

2020

ret = seteuid(uid);

2021

if(ret == -1){

2022

perror_plus("seteuid");

2023

}

2749

bool interface_was_up = interface_is_up(interface);

2750

errno = bring_up_interface(interface, delay);

2751

if(not interface_was_up){

2752

if(errno != 0){

2753

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

2754

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

2755

} else {

2756

errno = argz_add(&interfaces_to_take_down,

2757

&interfaces_to_take_down_size,

2758

interface);

2759

if(errno != 0){

2760

perror_plus("argz_add");

2761

}

2762

}

2763

}

2764

}

2765

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

2766

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

2767

}

2768

}

2769

2770

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

2771

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

2772

if(debug){

2773

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

2774

mc.interfaces);

2775

}

2776

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

2024

2777

}

2025

2778

2026

2779

if(quit_now){

2027

2780

goto end;

2028

2781

}

2029

2782

2030

ret = init_gnutls_global(pubkey, seckey);

2783

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

2031

2784

if(ret == -1){

2032

2785

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

2033

2786

exitcode = EX_UNAVAILABLE;

2040

2793

goto end;

2041

2794

}

2042

2795

2043

if(mkdtemp(tempdir) == NULL){

2796

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

2797

tempdir = mkdtemp(run_tempdir);

2798

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

2799

if(debug){

2800

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

2801

run_tempdir, old_tempdir);

2802

}

2803

tempdir = mkdtemp(old_tempdir);

2804

}

2805

if(tempdir == NULL){

2044

2806

perror_plus("mkdtemp");

2045

2807

goto end;

2046

2808

}

2047

tempdir_created = true;

2048

2809

2049

2810

if(quit_now){

2050

2811

goto end;

2051

2812

}

2052

2813

2053

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

2814

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

2054

2815

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

2055

2816

exitcode = EX_UNAVAILABLE;

2056

2817

goto end;

2066

2827

/* Connect directly, do not use Zeroconf */

2067

2828

/* (Mainly meant for debugging) */

2068

2829

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

2830

2069

2831

if(address == NULL){

2070

2832

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

2071

2833

exitcode = EX_USAGE;

2076

2838

goto end;

2077

2839

}

2078

2840

2079

uint16_t port;

2841

in_port_t port;

2080

2842

errno = 0;

2081

2843

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

2082

2844

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

2083

or tmpmax != (uint16_t)tmpmax){

2845

or tmpmax != (in_port_t)tmpmax){

2084

2846

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

2085

2847

exitcode = EX_USAGE;

2086

2848

goto end;

2087

2849

}

2088

2850

2089

2851

if(quit_now){

2090

2852

goto end;

2091

2853

}

2092

2854

2093

port = (uint16_t)tmpmax;

2855

port = (in_port_t)tmpmax;

2094

2856

*address = '\0';

2095

2857

/* Colon in address indicates IPv6 */

2096

2858

int af;

2112

2874

}

2113

2875

2114

2876

while(not quit_now){

2115

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

2877

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

2878

&mc);

2116

2879

if(quit_now or ret == 0){

2117

2880

break;

2118

2881

}

2120

2883

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

2121

2884

(int)retry_interval);

2122

2885

}

2123

sleep((int)retry_interval);

2886

sleep((unsigned int)retry_interval);

2124

2887

}

2125

2888

2126

if (not quit_now){

2889

if(not quit_now){

2127

2890

exitcode = EXIT_SUCCESS;

2128

2891

}

2129

2892

2144

2907

config.publish_domain = 0;

2145

2908

2146

2909

/* Allocate a new server */

2147

mc.server = avahi_server_new(avahi_simple_poll_get

2148

(mc.simple_poll), &config, NULL,

2149

NULL, &error);

2910

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2911

&config, NULL, NULL, &ret);

2150

2912

2151

2913

/* Free the Avahi configuration data */

2152

2914

avahi_server_config_free(&config);

2155

2917

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

2156

2918

if(mc.server == NULL){

2157

2919

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

2158

avahi_strerror(error));

2920

avahi_strerror(ret));

2159

2921

exitcode = EX_UNAVAILABLE;

2160

2922

goto end;

2161

2923

}

2167

2929

/* Create the Avahi service browser */

2168

2930

sb = avahi_s_service_browser_new(mc.server, if_index,

2169

2931

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2170

NULL, 0, browse_callback, NULL);

2932

NULL, 0, browse_callback,

2933

(void *)&mc);

2171

2934

if(sb == NULL){

2172

2935

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

2173

2936

avahi_strerror(avahi_server_errno(mc.server)));

2184

2947

if(debug){

2185

2948

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

2186

2949

}

2187

2188

ret = avahi_loop_with_timeout(mc.simple_poll,

2189

(int)(retry_interval * 1000));

2950

2951

ret = avahi_loop_with_timeout(simple_poll,

2952

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

2190

2953

if(debug){

2191

2954

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

2192

2955

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

2195

2958

end:

2196

2959

2197

2960

if(debug){

2198

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

2961

if(signal_received){

2962

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

2963

argv[0], signal_received,

2964

strsignal(signal_received));

2965

} else {

2966

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

2967

}

2199

2968

}

2200

2969

2201

2970

/* Cleanup things */

2971

free(mc.interfaces);

2972

2202

2973

if(sb != NULL)

2203

2974

avahi_s_service_browser_free(sb);

2204

2975

2205

2976

if(mc.server != NULL)

2206

2977

avahi_server_free(mc.server);

2207

2978

2208

if(mc.simple_poll != NULL)

2209

avahi_simple_poll_free(mc.simple_poll);

2979

if(simple_poll != NULL)

2980

avahi_simple_poll_free(simple_poll);

2210

2981

2211

2982

if(gnutls_initialized){

2212

2983

gnutls_certificate_free_credentials(mc.cred);

2213

gnutls_global_deinit();

2214

2984

gnutls_dh_params_deinit(mc.dh_params);

2215

2985

}

2216

2986

2224

2994

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

2225

2995

while(mc.current_server != NULL){

2226

2996

server *next = mc.current_server->next;

2997

#ifdef __GNUC__

2998

#pragma GCC diagnostic push

2999

#pragma GCC diagnostic ignored "-Wcast-qual"

3000

#endif

3001

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

3002

#ifdef __GNUC__

3003

#pragma GCC diagnostic pop

3004

#endif

2227

3005

free(mc.current_server);

2228

3006

mc.current_server = next;

2229

3007

}

2230

3008

}

2231

3009

2232

/* Run network hooks */

2233

run_network_hooks("stop", interface, delay);

2234

2235

/* Re-raise priviliges */

3010

/* Re-raise privileges */

2236

3011

{

2237

errno = 0;

2238

ret = seteuid(0);

2239

if(ret == -1){

2240

perror_plus("seteuid");

3012

ret = raise_privileges();

3013

if(ret != 0){

3014

errno = ret;

3015

perror_plus("Failed to raise privileges");

3016

} else {

3017

3018

/* Run network hooks */

3019

run_network_hooks("stop", interfaces_hooks != NULL ?

3020

interfaces_hooks : "", delay);

3021

3022

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

3023

{

3024

char *interface = NULL;

3025

while((interface=argz_next(interfaces_to_take_down,

3026

interfaces_to_take_down_size,

3027

interface))){

3028

ret = take_down_interface(interface);

3029

if(ret != 0){

3030

errno = ret;

3031

perror_plus("Failed to take down interface");

3032

}

3033

}

3034

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

3035

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

3036

" down\n");

3037

}

3038

}

2241

3039

}

2242

3040

2243

/* Take down the network interface */

2244

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

2245

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

2246

if(ret == -1){

2247

perror_plus("ioctl SIOCGIFFLAGS");

2248

} else if(network.ifr_flags & IFF_UP){

2249

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

2250

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

2251

if(ret == -1){

2252

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2253

}

2254

}

2255

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

2256

if(ret == -1){

2257

perror_plus("close");

2258

}

3041

ret = lower_privileges_permanently();

3042

if(ret != 0){

3043

errno = ret;

3044

perror_plus("Failed to lower privileges permanently");

2259

3045

}

2260

3046

}

2261

/* Lower privileges permanently */

2262

errno = 0;

2263

ret = setuid(uid);

2264

if(ret == -1){

2265

perror_plus("setuid");

3047

3048

free(interfaces_to_take_down);

3049

free(interfaces_hooks);

3050

3051

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

3052

uintmax_t level){

3053

struct dirent **direntries = NULL;

3054

int dret;

3055

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

3056

O_RDONLY

3057

| O_NOFOLLOW

3058

| O_DIRECTORY

3059

| O_PATH));

3060

if(dir_fd == -1){

3061

perror_plus("open");

3062

}

3063

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

3064

notdotentries, alphasort);

3065

if(numentries >= 0){

3066

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

3067

if(debug){

3068

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

3069

dirname, direntries[i]->d_name);

3070

}

3071

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

3072

if(dret == -1){

3073

if(errno == EISDIR){

3074

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

3075

AT_REMOVEDIR);

3076

}

3077

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

3078

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

3079

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

3080

/* Recurse only in this special case */

3081

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

3082

dret = 0;

3083

}

3084

if(dret == -1){

3085

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

3086

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

3087

}

3088

}

3089

free(direntries[i]);

3090

}

3091

3092

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

3093

free(direntries);

3094

if(numentries == -1){

3095

perror_plus("scandirat");

3096

}

3097

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3098

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

3099

perror_plus("rmdir");

3100

}

3101

} else {

3102

perror_plus("scandirat");

3103

}

3104

close(dir_fd);

2266

3105

}

2267

3106

2268

3107

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

2269

if(tempdir_created){

2270

struct dirent **direntries = NULL;

2271

struct dirent *direntry = NULL;

2272

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

2273

alphasort);

2274

if (numentries > 0){

2275

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

2276

direntry = direntries[i];

2277

char *fullname = NULL;

2278

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

2279

direntry->d_name);

2280

if(ret < 0){

2281

perror_plus("asprintf");

2282

continue;

2283

}

2284

ret = remove(fullname);

2285

if(ret == -1){

2286

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

2287

strerror(errno));

2288

}

2289

free(fullname);

2290

}

2291

}

2292

2293

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

2294

free(direntries);

2295

if (numentries == -1){

2296

perror_plus("scandir");

2297

}

2298

ret = rmdir(tempdir);

2299

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

2300

perror_plus("rmdir");

2301

}

3108

if(tempdir != NULL){

3109

clean_dir_at(-1, tempdir, 0);

2302

3110

}

2303

3111

2304

3112

if(quit_now){