/mandos/release : revision 237.15.10

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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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*

15

* 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 /* not _LARGEFILE_SOURCE */

35

#endif

36

#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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40

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

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

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stdout, ferror() */

44

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

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stdout, ferror(), remove() */

44

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

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

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

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strtof(), abort() */

48

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

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

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asprintf(), strncpy() */

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

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

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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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getnameinfo() */

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#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

*/

63

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#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,

64

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

65

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

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66

program_invocation_short_name */

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

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

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*/

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

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

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

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unlinkat() */

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

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

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

83

78

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

84

79

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

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80

argp_state, struct argp,

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87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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89

WEXITSTATUS(), WTERMSIG() */

95

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

96

#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() */

100

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

101

EAI_SYSTEM, gai_strerror() */

102

90

103

91

#ifdef __linux__

104

92

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

146

134

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

147

135

char *connect_to = NULL;

148

136

const char *hookdir = HOOKDIR;

149

int hookdir_fd = -1;

150

uid_t uid = 65534;

151

gid_t gid = 65534;

152

137

153

138

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

154

139

typedef struct server{

155

140

const char *ip;

156

in_port_t port;

141

uint16_t port;

157

142

AvahiIfIndex if_index;

158

143

int af;

159

144

struct timespec last_seen;

163

148

164

149

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

165

150

typedef struct {

151

AvahiSimplePoll *simple_poll;

166

152

AvahiServer *server;

167

153

gnutls_certificate_credentials_t cred;

168

154

unsigned int dh_bits;

170

156

const char *priority;

171

157

gpgme_ctx_t ctx;

172

158

server *current_server;

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char *interfaces;

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size_t interfaces_size;

175

159

} mandos_context;

176

160

177

/* global so signal handler can reach it*/

178

AvahiSimplePoll *simple_poll;

161

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

162

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

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.dh_bits = 1024, .priority = "SECURE256"

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

165

.current_server = NULL };

179

166

180

167

sig_atomic_t quit_now = 0;

181

168

int signal_received = 0;

182

169

183

170

/* Function to use when printing errors */

184

171

void perror_plus(const char *print_text){

185

int e = errno;

186

172

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

187

173

program_invocation_short_name);

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errno = e;

189

174

perror(print_text);

190

175

}

191

176

192

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

193

177

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

194

178

va_list ap;

195

179

va_start (ap, format);

196

180

197

181

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

198

182

program_invocation_short_name));

199

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

183

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

200

184

}

201

185

202

186

/*

204

188

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

205

189

* "buffer_length" is how much is already used.

206

190

*/

207

__attribute__((nonnull, warn_unused_result))

208

191

size_t incbuffer(char **buffer, size_t buffer_length,

209

192

size_t buffer_capacity){

210

193

if(buffer_length + BUFFER_SIZE > buffer_capacity){

211

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

212

if(new_buf == NULL){

213

int old_errno = errno;

214

free(*buffer);

215

errno = old_errno;

216

*buffer = NULL;

194

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

195

if(buffer == NULL){

217

196

return 0;

218

197

}

219

*buffer = new_buf;

220

198

buffer_capacity += BUFFER_SIZE;

221

199

}

222

200

return buffer_capacity;

223

201

}

224

202

225

203

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

226

__attribute__((nonnull, warn_unused_result))

227

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

228

int af, server **current_server){

204

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

205

int af){

229

206

int ret;

230

207

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

231

208

if(new_server == NULL){

232

209

perror_plus("malloc");

233

return false;

210

return -1;

234

211

}

235

212

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

236

213

.port = port,

238

215

.af = af };

239

216

if(new_server->ip == NULL){

240

217

perror_plus("strdup");

241

free(new_server);

242

return false;

243

}

244

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

245

if(ret == -1){

246

perror_plus("clock_gettime");

247

#ifdef __GNUC__

248

#pragma GCC diagnostic push

249

#pragma GCC diagnostic ignored "-Wcast-qual"

250

#endif

251

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

252

#ifdef __GNUC__

253

#pragma GCC diagnostic pop

254

#endif

255

free(new_server);

256

return false;

218

return -1;

257

219

}

258

220

/* Special case of first server */

259

if(*current_server == NULL){

221

if (mc.current_server == NULL){

260

222

new_server->next = new_server;

261

223

new_server->prev = new_server;

262

*current_server = new_server;

224

mc.current_server = new_server;

225

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

263

226

} else {

264

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

265

new_server->next = *current_server;

266

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

227

new_server->next = mc.current_server;

228

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

267

229

new_server->prev->next = new_server;

268

(*current_server)->prev = new_server;

269

}

270

return true;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

271

238

}

272

239

273

240

/*

274

241

* Initialize GPGME.

275

242

*/

276

__attribute__((nonnull, warn_unused_result))

277

static bool init_gpgme(const char * const seckey,

278

const char * const pubkey,

279

const char * const tempdir,

280

mandos_context *mc){

243

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

244

const char *tempdir){

281

245

gpgme_error_t rc;

282

246

gpgme_engine_info_t engine_info;

283

247

248

284

249

/*

285

250

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

286

251

*/

287

bool import_key(const char * const filename){

252

bool import_key(const char *filename){

288

253

int ret;

289

254

int fd;

290

255

gpgme_data_t pgp_data;

302

267

return false;

303

268

}

304

269

305

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

270

rc = gpgme_op_import(mc.ctx, pgp_data);

306

271

if(rc != GPG_ERR_NO_ERROR){

307

272

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

308

273

gpgme_strsource(rc), gpgme_strerror(rc));

309

274

return false;

310

275

}

311

276

312

ret = close(fd);

277

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

313

278

if(ret == -1){

314

279

perror_plus("close");

315

280

}

352

317

}

353

318

354

319

/* Create new GPGME "context" */

355

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

320

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

356

321

if(rc != GPG_ERR_NO_ERROR){

357

322

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

358

323

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

371

336

* Decrypt OpenPGP data.

372

337

* Returns -1 on error

373

338

*/

374

__attribute__((nonnull, warn_unused_result))

375

339

static ssize_t pgp_packet_decrypt(const char *cryptotext,

376

340

size_t crypto_size,

377

char **plaintext,

378

mandos_context *mc){

341

char **plaintext){

379

342

gpgme_data_t dh_crypto, dh_plain;

380

343

gpgme_error_t rc;

381

344

ssize_t ret;

407

370

408

371

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

409

372

data buffer */

410

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

373

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

411

374

if(rc != GPG_ERR_NO_ERROR){

412

375

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

413

376

gpgme_strsource(rc), gpgme_strerror(rc));

414

377

plaintext_length = -1;

415

378

if(debug){

416

379

gpgme_decrypt_result_t result;

417

result = gpgme_op_decrypt_result(mc->ctx);

380

result = gpgme_op_decrypt_result(mc.ctx);

418

381

if(result == NULL){

419

382

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

420

383

} else {

497

460

return plaintext_length;

498

461

}

499

462

500

__attribute__((warn_unused_result, const))

501

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

502

if(str == NULL)

503

return "(unknown)";

504

return str;

505

}

506

507

__attribute__((warn_unused_result))

508

static const char *safer_gnutls_strerror(int value){

509

const char *ret = gnutls_strerror(value);

510

return safe_string(ret);

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

466

if(ret == NULL)

467

ret = "(unknown)";

468

return ret;

511

469

}

512

470

513

471

/* GnuTLS log function callback */

514

__attribute__((nonnull))

515

472

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

516

473

const char* string){

517

474

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

518

475

}

519

476

520

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

521

477

static int init_gnutls_global(const char *pubkeyfilename,

522

const char *seckeyfilename,

523

const char *dhparamsfilename,

524

mandos_context *mc){

478

const char *seckeyfilename){

525

479

int ret;

526

unsigned int uret;

527

480

528

481

if(debug){

529

482

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

530

483

}

531

484

485

ret = gnutls_global_init();

486

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

489

return -1;

490

}

491

532

492

if(debug){

533

493

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

534

494

* - GnuTLS manual

538

498

}

539

499

540

500

/* OpenPGP credentials */

541

ret = gnutls_certificate_allocate_credentials(&mc->cred);

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

542

502

if(ret != GNUTLS_E_SUCCESS){

543

503

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

544

504

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

545

506

return -1;

546

507

}

547

508

553

514

}

554

515

555

516

ret = gnutls_certificate_set_openpgp_key_file

556

(mc->cred, pubkeyfilename, seckeyfilename,

517

(mc.cred, pubkeyfilename, seckeyfilename,

557

518

GNUTLS_OPENPGP_FMT_BASE64);

558

519

if(ret != GNUTLS_E_SUCCESS){

559

520

fprintf_plus(stderr,

565

526

}

566

527

567

528

/* GnuTLS server initialization */

568

ret = gnutls_dh_params_init(&mc->dh_params);

529

ret = gnutls_dh_params_init(&mc.dh_params);

569

530

if(ret != GNUTLS_E_SUCCESS){

570

531

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

571

532

" initialization: %s\n",

572

533

safer_gnutls_strerror(ret));

573

534

goto globalfail;

574

535

}

575

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

576

if(dhparamsfilename != NULL){

577

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

578

do {

579

int dhpfile = open(dhparamsfilename, O_RDONLY);

580

if(dhpfile == -1){

581

perror_plus("open");

582

dhparamsfilename = NULL;

583

break;

584

}

585

size_t params_capacity = 0;

586

while(true){

587

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

588

(size_t)params.size,

589

(size_t)params_capacity);

590

if(params_capacity == 0){

591

perror_plus("incbuffer");

592

free(params.data);

593

params.data = NULL;

594

dhparamsfilename = NULL;

595

break;

596

}

597

ssize_t bytes_read = read(dhpfile,

598

params.data + params.size,

599

BUFFER_SIZE);

600

/* EOF */

601

if(bytes_read == 0){

602

break;

603

}

604

/* check bytes_read for failure */

605

if(bytes_read < 0){

606

perror_plus("read");

607

free(params.data);

608

params.data = NULL;

609

dhparamsfilename = NULL;

610

break;

611

}

612

params.size += (unsigned int)bytes_read;

613

}

614

if(params.data == NULL){

615

dhparamsfilename = NULL;

616

}

617

if(dhparamsfilename == NULL){

618

break;

619

}

620

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

621

GNUTLS_X509_FMT_PEM);

622

if(ret != GNUTLS_E_SUCCESS){

623

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

624

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

625

safer_gnutls_strerror(ret));

626

dhparamsfilename = NULL;

627

}

628

} while(false);

629

}

630

if(dhparamsfilename == NULL){

631

if(mc->dh_bits == 0){

632

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

633

/* Try to read the private key file */

634

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

635

do {

636

int secfile = open(seckeyfilename, O_RDONLY);

637

if(secfile == -1){

638

perror_plus("open");

639

break;

640

}

641

size_t buffer_capacity = 0;

642

while(true){

643

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

644

(size_t)buffer.size,

645

(size_t)buffer_capacity);

646

if(buffer_capacity == 0){

647

perror_plus("incbuffer");

648

free(buffer.data);

649

buffer.data = NULL;

650

break;

651

}

652

ssize_t bytes_read = read(secfile,

653

buffer.data + buffer.size,

654

BUFFER_SIZE);

655

/* EOF */

656

if(bytes_read == 0){

657

break;

658

}

659

/* check bytes_read for failure */

660

if(bytes_read < 0){

661

perror_plus("read");

662

free(buffer.data);

663

buffer.data = NULL;

664

break;

665

}

666

buffer.size += (unsigned int)bytes_read;

667

}

668

close(secfile);

669

} while(false);

670

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

671

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

672

if(buffer.data != NULL){

673

{

674

gnutls_openpgp_privkey_t privkey = NULL;

675

ret = gnutls_openpgp_privkey_init(&privkey);

676

if(ret != GNUTLS_E_SUCCESS){

677

fprintf_plus(stderr, "Error initializing OpenPGP key"

678

" structure: %s",

679

safer_gnutls_strerror(ret));

680

free(buffer.data);

681

buffer.data = NULL;

682

} else {

683

ret = gnutls_openpgp_privkey_import

684

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

685

if(ret != GNUTLS_E_SUCCESS){

686

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

687

safer_gnutls_strerror(ret));

688

privkey = NULL;

689

}

690

free(buffer.data);

691

buffer.data = NULL;

692

if(privkey != NULL){

693

/* Use private key to suggest an appropriate

694

sec_param */

695

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

696

gnutls_openpgp_privkey_deinit(privkey);

697

if(debug){

698

fprintf_plus(stderr, "This OpenPGP key implies using"

699

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

700

safe_string(gnutls_sec_param_get_name

701

(sec_param)));

702

}

703

}

704

}

705

}

706

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

707

/* Err on the side of caution */

708

sec_param = GNUTLS_SEC_PARAM_ULTRA;

709

if(debug){

710

fprintf_plus(stderr, "Falling back to security parameter"

711

" \"%s\"\n",

712

safe_string(gnutls_sec_param_get_name

713

(sec_param)));

714

}

715

}

716

}

717

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

718

if(uret != 0){

719

mc->dh_bits = uret;

720

if(debug){

721

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

722

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

723

safe_string(gnutls_sec_param_get_name

724

(sec_param)),

725

mc->dh_bits);

726

}

727

} else {

728

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

729

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

730

safe_string(gnutls_sec_param_get_name

731

(sec_param)),

732

safer_gnutls_strerror(ret));

733

goto globalfail;

734

}

735

} else if(debug){

736

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

737

mc->dh_bits);

738

}

739

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

740

if(ret != GNUTLS_E_SUCCESS){

741

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

742

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

743

safer_gnutls_strerror(ret));

744

goto globalfail;

745

}

746

}

747

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

536

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

537

if(ret != GNUTLS_E_SUCCESS){

538

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

539

safer_gnutls_strerror(ret));

540

goto globalfail;

541

}

542

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

748

544

749

545

return 0;

750

546

751

547

globalfail:

752

548

753

gnutls_certificate_free_credentials(mc->cred);

754

gnutls_dh_params_deinit(mc->dh_params);

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

755

552

return -1;

756

553

}

757

554

758

__attribute__((nonnull, warn_unused_result))

759

static int init_gnutls_session(gnutls_session_t *session,

760

mandos_context *mc){

555

static int init_gnutls_session(gnutls_session_t *session){

761

556

int ret;

762

557

/* GnuTLS session creation */

763

558

do {

775

570

{

776

571

const char *err;

777

572

do {

778

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

573

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

779

574

if(quit_now){

780

575

gnutls_deinit(*session);

781

576

return -1;

792

587

793

588

do {

794

589

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

795

mc->cred);

590

mc.cred);

796

591

if(quit_now){

797

592

gnutls_deinit(*session);

798

593

return -1;

808

603

/* ignore client certificate if any. */

809

604

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

810

605

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

811

608

return 0;

812

609

}

813

610

815

612

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

816

613

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

817

614

818

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

819

__attribute__((warn_unused_result))

820

int raise_privileges(void){

821

int old_errno = errno;

822

int ret = 0;

823

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

824

ret = errno;

825

}

826

errno = old_errno;

827

return ret;

828

}

829

830

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

831

__attribute__((warn_unused_result))

832

int raise_privileges_permanently(void){

833

int old_errno = errno;

834

int ret = raise_privileges();

835

if(ret != 0){

836

errno = old_errno;

837

return ret;

838

}

839

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

840

ret = errno;

841

}

842

errno = old_errno;

843

return ret;

844

}

845

846

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

847

__attribute__((warn_unused_result))

848

int lower_privileges(void){

849

int old_errno = errno;

850

int ret = 0;

851

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

852

ret = errno;

853

}

854

errno = old_errno;

855

return ret;

856

}

857

858

/* Lower privileges permanently */

859

__attribute__((warn_unused_result))

860

int lower_privileges_permanently(void){

861

int old_errno = errno;

862

int ret = 0;

863

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

864

ret = errno;

865

}

866

errno = old_errno;

867

return ret;

868

}

869

870

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

871

__attribute__((nonnull, warn_unused_result))

872

static bool add_delete_local_route(const bool add,

873

const char *address,

874

AvahiIfIndex if_index){

875

int ret;

876

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

877

char add_arg[] = "add";

878

char delete_arg[] = "delete";

879

char debug_flag[] = "--debug";

880

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

881

if(pluginhelperdir == NULL){

882

if(debug){

883

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

884

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

885

}

886

return false;

887

}

888

889

char interface[IF_NAMESIZE];

890

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

891

perror_plus("if_indextoname");

892

return false;

893

}

894

895

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

896

if(devnull == -1){

897

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

898

return false;

899

}

900

pid_t pid = fork();

901

if(pid == 0){

902

/* Child */

903

/* Raise privileges */

904

errno = raise_privileges_permanently();

905

if(errno != 0){

906

perror_plus("Failed to raise privileges");

907

/* _exit(EX_NOPERM); */

908

} else {

909

/* Set group */

910

errno = 0;

911

ret = setgid(0);

912

if(ret == -1){

913

perror_plus("setgid");

914

_exit(EX_NOPERM);

915

}

916

/* Reset supplementary groups */

917

errno = 0;

918

ret = setgroups(0, NULL);

919

if(ret == -1){

920

perror_plus("setgroups");

921

_exit(EX_NOPERM);

922

}

923

}

924

ret = dup2(devnull, STDIN_FILENO);

925

if(ret == -1){

926

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

927

_exit(EX_OSERR);

928

}

929

ret = close(devnull);

930

if(ret == -1){

931

perror_plus("close");

932

_exit(EX_OSERR);

933

}

934

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

935

if(ret == -1){

936

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

937

_exit(EX_OSERR);

938

}

939

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

940

O_RDONLY

941

| O_DIRECTORY

942

| O_PATH

943

| O_CLOEXEC));

944

if(helperdir_fd == -1){

945

perror_plus("open");

946

_exit(EX_UNAVAILABLE);

947

}

948

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

949

helper, O_RDONLY));

950

if(helper_fd == -1){

951

perror_plus("openat");

952

close(helperdir_fd);

953

_exit(EX_UNAVAILABLE);

954

}

955

close(helperdir_fd);

956

#ifdef __GNUC__

957

#pragma GCC diagnostic push

958

#pragma GCC diagnostic ignored "-Wcast-qual"

959

#endif

960

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

961

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

962

interface, debug ? debug_flag : NULL, NULL },

963

environ) == -1){

964

#ifdef __GNUC__

965

#pragma GCC diagnostic pop

966

#endif

967

perror_plus("fexecve");

968

_exit(EXIT_FAILURE);

969

}

970

}

971

if(pid == -1){

972

perror_plus("fork");

973

return false;

974

}

975

int status;

976

pid_t pret = -1;

977

errno = 0;

978

do {

979

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

980

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

981

int errno_raising = 0;

982

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

983

errno_raising = errno;

984

perror_plus("Failed to raise privileges in order to"

985

" kill helper program");

986

}

987

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

988

perror_plus("kill");

989

}

990

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

991

perror_plus("Failed to lower privileges after killing"

992

" helper program");

993

}

994

return false;

995

}

996

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

997

if(pret == -1){

998

perror_plus("waitpid");

999

return false;

1000

}

1001

if(WIFEXITED(status)){

1002

if(WEXITSTATUS(status) != 0){

1003

fprintf_plus(stderr, "Error: iprouteadddel exited"

1004

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

1005

return false;

1006

}

1007

return true;

1008

}

1009

if(WIFSIGNALED(status)){

1010

fprintf_plus(stderr, "Error: iprouteadddel died by"

1011

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

1012

return false;

1013

}

1014

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

1015

return false;

1016

}

1017

1018

__attribute__((nonnull, warn_unused_result))

1019

static bool add_local_route(const char *address,

1020

AvahiIfIndex if_index){

1021

if(debug){

1022

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

1023

}

1024

return add_delete_local_route(true, address, if_index);

1025

}

1026

1027

__attribute__((nonnull, warn_unused_result))

1028

static bool delete_local_route(const char *address,

1029

AvahiIfIndex if_index){

1030

if(debug){

1031

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

1032

}

1033

return add_delete_local_route(false, address, if_index);

1034

}

1035

1036

615

/* Called when a Mandos server is found */

1037

__attribute__((nonnull, warn_unused_result))

1038

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

616

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

1039

617

AvahiIfIndex if_index,

1040

int af, mandos_context *mc){

618

int af){

1041

619

int ret, tcp_sd = -1;

1042

620

ssize_t sret;

1043

struct sockaddr_storage to;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1044

625

char *buffer = NULL;

1045

626

char *decrypted_buffer = NULL;

1046

627

size_t buffer_length = 0;

1049

630

int retval = -1;

1050

631

gnutls_session_t session;

1051

632

int pf; /* Protocol family */

1052

bool route_added = false;

1053

633

1054

634

errno = 0;

1055

635

1071

651

return -1;

1072

652

}

1073

653

1074

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

1075

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

1076

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

1077

bool match = false;

1078

{

1079

char *interface = NULL;

1080

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

1081

interface))){

1082

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

1083

match = true;

1084

break;

1085

}

1086

}

1087

}

1088

if(not match){

1089

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

1090

connect to the server */

1091

if(debug){

1092

char interface[IF_NAMESIZE];

1093

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

1094

perror_plus("if_indextoname");

1095

} else {

1096

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

1097

" \"%s\"\n",

1098

if_indextoname((unsigned int)if_index,

1099

interface));

1100

}

1101

}

1102

return -1;

1103

}

1104

}

1105

1106

ret = init_gnutls_session(&session, mc);

654

ret = init_gnutls_session(&session);

1107

655

if(ret != 0){

1108

656

return -1;

1109

657

}

1110

658

1111

659

if(debug){

1112

660

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

1113

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

661

PRIu16 "\n", ip, port);

1114

662

}

1115

663

1116

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

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1117

665

if(tcp_sd < 0){

1118

666

int e = errno;

1119

667

perror_plus("socket");

1126

674

goto mandos_end;

1127

675

}

1128

676

677

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

1129

678

if(af == AF_INET6){

1130

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

1131

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

1132

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

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1133

681

} else { /* IPv4 */

1134

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

1135

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

1136

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

682

to.in.sin_family = (sa_family_t)af;

683

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

1137

684

}

1138

685

if(ret < 0 ){

1139

686

int e = errno;

1148

695

goto mandos_end;

1149

696

}

1150

697

if(af == AF_INET6){

1151

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

1152

if(IN6_IS_ADDR_LINKLOCAL

1153

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

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

1154

705

if(if_index == AVAHI_IF_UNSPEC){

1155

706

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

1156

707

" incomplete without a network interface\n");

1158

709

goto mandos_end;

1159

710

}

1160

711

/* Set the network interface number as scope */

1161

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

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1162

713

}

1163

714

} else {

1164

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

715

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

716

-Wconversion and

717

-Wunreachable-code */

1165

718

}

1166

719

1167

720

if(quit_now){

1175

728

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

1176

729

perror_plus("if_indextoname");

1177

730

} else {

1178

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

1179

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

731

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

732

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

1180

733

}

1181

734

} else {

1182

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

1183

ip, (uintmax_t)port);

735

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

736

ip, port);

1184

737

}

1185

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1186

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1187

if(af == AF_INET6){

1188

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

1189

sizeof(struct sockaddr_in6),

1190

addrstr, sizeof(addrstr), NULL, 0,

1191

NI_NUMERICHOST);

1192

} else {

1193

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

1194

sizeof(struct sockaddr_in),

1195

addrstr, sizeof(addrstr), NULL, 0,

1196

NI_NUMERICHOST);

1197

}

1198

if(ret == EAI_SYSTEM){

1199

perror_plus("getnameinfo");

1200

} else if(ret != 0) {

1201

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

1202

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

1203

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

1204

}

1205

}

1206

1207

if(quit_now){

1208

errno = EINTR;

1209

goto mandos_end;

1210

}

1211

1212

while(true){

1213

if(af == AF_INET6){

1214

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

1215

sizeof(struct sockaddr_in6));

1216

} else {

1217

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

1218

sizeof(struct sockaddr_in));

1219

}

1220

if(ret < 0){

1221

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

1222

and if_index != AVAHI_IF_UNSPEC

1223

and connect_to == NULL

1224

and not route_added and

1225

((af == AF_INET6 and not

1226

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1227

&to)->sin6_addr)))

1228

or (af == AF_INET and

1229

/* Not a a IPv4LL address */

1230

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

1231

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

1232

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

1233

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

1234

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

1235

connect to a Mandos server announced by Avahi on a server

1236

host with a global address. Work around this by retrying

1237

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

1238

1239

Avahi bug reference:

1240

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

1241

https://bugs.debian.org/587961

1242

*/

1243

if(debug){

1244

fprintf_plus(stderr, "Mandos server unreachable, trying"

1245

" direct route\n");

1246

}

1247

int e = errno;

1248

route_added = add_local_route(ip, if_index);

1249

if(route_added){

1250

continue;

1251

}

1252

errno = e;

1253

}

1254

if(errno != ECONNREFUSED or debug){

1255

int e = errno;

1256

perror_plus("connect");

1257

errno = e;

1258

}

1259

goto mandos_end;

1260

}

1261

1262

if(quit_now){

1263

errno = EINTR;

1264

goto mandos_end;

1265

}

1266

break;

740

const char *pcret;

741

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

744

} else {

745

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

746

sizeof(addrstr));

747

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

754

}

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

760

}

761

762

if(af == AF_INET6){

763

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

764

} else {

765

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

766

}

767

if(ret < 0){

768

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

769

int e = errno;

770

perror_plus("connect");

771

errno = e;

772

}

773

goto mandos_end;

774

}

775

776

if(quit_now){

777

errno = EINTR;

778

goto mandos_end;

1267

779

}

1268

780

1269

781

const char *out = mandos_protocol_version;

1305

817

goto mandos_end;

1306

818

}

1307

819

1308

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

1309

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

1310

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

1311

gnutls_transport_set_ptr(session,

1312

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1313

822

1314

823

if(quit_now){

1315

824

errno = EINTR;

1420

929

if(buffer_length > 0){

1421

930

ssize_t decrypted_buffer_size;

1422

931

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1423

&decrypted_buffer, mc);

932

&decrypted_buffer);

1424

933

if(decrypted_buffer_size >= 0){

1425

934

1426

clearerr(stdout);

1427

935

written = 0;

1428

936

while(written < (size_t) decrypted_buffer_size){

1429

937

if(quit_now){

1445

953

}

1446

954

written += (size_t)ret;

1447

955

}

1448

ret = fflush(stdout);

1449

if(ret != 0){

1450

int e = errno;

1451

if(debug){

1452

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

1453

strerror(errno));

1454

}

1455

errno = e;

1456

goto mandos_end;

1457

}

1458

956

retval = 0;

1459

957

}

1460

958

}

1463

961

1464

962

mandos_end:

1465

963

{

1466

if(route_added){

1467

if(not delete_local_route(ip, if_index)){

1468

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

1469

" interface %d", ip, if_index);

1470

}

1471

}

1472

964

int e = errno;

1473

965

free(decrypted_buffer);

1474

966

free(buffer);

1475

967

if(tcp_sd >= 0){

1476

ret = close(tcp_sd);

968

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

1477

969

}

1478

970

if(ret == -1){

1479

971

if(e == 0){

1491

983

return retval;

1492

984

}

1493

985

1494

__attribute__((nonnull))

1495

986

static void resolve_callback(AvahiSServiceResolver *r,

1496

987

AvahiIfIndex interface,

1497

988

AvahiProtocol proto,

1505

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1506

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1507

998

flags,

1508

void *mc){

1509

if(r == NULL){

1510

return;

1511

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1512

1001

1513

1002

/* Called whenever a service has been resolved successfully or

1514

1003

timed out */

1515

1004

1516

1005

if(quit_now){

1517

avahi_s_service_resolver_free(r);

1518

1006

return;

1519

1007

}

1520

1008

1524

1012

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

1525

1013

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

1526

1014

domain,

1527

avahi_strerror(avahi_server_errno

1528

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1529

1016

break;

1530

1017

1531

1018

case AVAHI_RESOLVER_FOUND:

1537

1024

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

1538

1025

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

1539

1026

}

1540

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

1541

interface,

1542

avahi_proto_to_af(proto),

1543

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1544

1029

if(ret == 0){

1545

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1546

1031

} else {

1547

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

1548

avahi_proto_to_af(proto),

1549

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

1550

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

1551

" list\n", name);

1552

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1553

1034

}

1554

1035

}

1555

1036

}

1565

1046

const char *domain,

1566

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1567

1048

flags,

1568

void *mc){

1569

if(b == NULL){

1570

return;

1571

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1572

1051

1573

1052

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

1574

1053

is removed from the LAN */

1582

1061

case AVAHI_BROWSER_FAILURE:

1583

1062

1584

1063

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

1585

avahi_strerror(avahi_server_errno

1586

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

1587

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1588

1066

return;

1589

1067

1590

1068

case AVAHI_BROWSER_NEW:

1593

1071

the callback function is called the Avahi server will free the

1594

1072

resolver for us. */

1595

1073

1596

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

1597

interface, protocol, name, type,

1598

domain, protocol, 0,

1599

resolve_callback, mc) == NULL)

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1600

1077

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

1601

1078

" %s\n", name,

1602

avahi_strerror(avahi_server_errno

1603

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1604

1080

break;

1605

1081

1606

1082

case AVAHI_BROWSER_REMOVE:

1625

1101

signal_received = sig;

1626

1102

int old_errno = errno;

1627

1103

/* set main loop to exit */

1628

if(simple_poll != NULL){

1629

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1630

1106

}

1631

1107

errno = old_errno;

1632

1108

}

1633

1109

1634

__attribute__((nonnull, warn_unused_result))

1635

1110

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

1636

1111

int ret;

1637

int old_errno;

1638

1112

1639

1113

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

1640

1114

if(s < 0){

1641

old_errno = errno;

1642

1115

perror_plus("socket");

1643

errno = old_errno;

1644

1116

return false;

1645

1117

}

1646

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

1647

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

1118

strcpy(ifr->ifr_name, ifname);

1648

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1649

1120

if(ret == -1){

1650

1121

if(debug){

1651

old_errno = errno;

1652

1122

perror_plus("ioctl SIOCGIFFLAGS");

1653

errno = old_errno;

1654

1123

}

1655

1124

return false;

1656

1125

}

1657

1126

return true;

1658

1127

}

1659

1128

1660

__attribute__((nonnull, warn_unused_result))

1661

1129

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

1662

1130

1663

1131

/* Reject the loopback device */

1705

1173

* corresponds to an acceptable network device.

1706

1174

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

1707

1175

*/

1708

__attribute__((nonnull, warn_unused_result))

1709

1176

int good_interface(const struct dirent *if_entry){

1710

1177

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

1711

1178

return 0;

1727

1194

}

1728

1195

1729

1196

/*

1730

* This function determines if a network interface is up.

1731

*/

1732

__attribute__((nonnull, warn_unused_result))

1733

bool interface_is_up(const char *interface){

1734

struct ifreq ifr;

1735

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

1736

if(debug){

1737

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

1738

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

1739

}

1740

return false;

1741

}

1742

1743

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

1744

}

1745

1746

/*

1747

* This function determines if a network interface is running

1748

*/

1749

__attribute__((nonnull, warn_unused_result))

1750

bool interface_is_running(const char *interface){

1751

struct ifreq ifr;

1752

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

1753

if(debug){

1754

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

1755

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

1756

}

1757

return false;

1758

}

1759

1760

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

1761

}

1762

1763

__attribute__((nonnull, pure, warn_unused_result))

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

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

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

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

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1764

1239

int notdotentries(const struct dirent *direntry){

1765

1240

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

1766

1241

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

1773

1248

}

1774

1249

1775

1250

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

1776

__attribute__((nonnull, warn_unused_result))

1777

1251

int runnable_hook(const struct dirent *direntry){

1778

1252

int ret;

1779

1253

size_t sret;

1787

1261

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

1788

1262

"abcdefghijklmnopqrstuvwxyz"

1789

1263

"0123456789"

1790

"_.-");

1264

"_-");

1791

1265

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

1792

1266

/* Contains non-allowed characters */

1793

1267

if(debug){

1797

1271

return 0;

1798

1272

}

1799

1273

1800

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

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1801

1282

if(ret == -1){

1802

1283

if(debug){

1803

1284

perror_plus("Could not stat hook");

1827

1308

return 1;

1828

1309

}

1829

1310

1830

__attribute__((nonnull, warn_unused_result))

1831

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1832

mandos_context *mc){

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1833

1312

int ret;

1834

1313

struct timespec now;

1835

1314

struct timespec waited_time;

1836

1315

intmax_t block_time;

1837

1316

1838

1317

while(true){

1839

if(mc->current_server == NULL){

1840

if(debug){

1318

if(mc.current_server == NULL){

1319

if (debug){

1841

1320

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

1842

1321

" No timeout!\n");

1843

1322

}

1844

1323

ret = avahi_simple_poll_iterate(s, -1);

1845

1324

} else {

1846

if(debug){

1325

if (debug){

1847

1326

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

1848

1327

" it, or wait\n");

1849

1328

}

1856

1335

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

1857

1336

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

1858

1337

waited_time.tv_sec = (now.tv_sec

1859

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

1338

- mc.current_server->last_seen.tv_sec);

1860

1339

waited_time.tv_nsec = (now.tv_nsec

1861

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

1340

- mc.current_server->last_seen.tv_nsec);

1862

1341

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

1863

1342

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

1864

1343

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

1866

1345

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

1867

1346

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

1868

1347

1869

if(debug){

1348

if (debug){

1870

1349

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

1871

1350

block_time);

1872

1351

}

1873

1352

1874

1353

if(block_time <= 0){

1875

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

1876

mc->current_server->port,

1877

mc->current_server->if_index,

1878

mc->current_server->af, mc);

1354

ret = start_mandos_communication(mc.current_server->ip,

1355

mc.current_server->port,

1356

mc.current_server->if_index,

1357

mc.current_server->af);

1879

1358

if(ret == 0){

1880

avahi_simple_poll_quit(s);

1359

avahi_simple_poll_quit(mc.simple_poll);

1881

1360

return 0;

1882

1361

}

1883

1362

ret = clock_gettime(CLOCK_MONOTONIC,

1884

&mc->current_server->last_seen);

1363

&mc.current_server->last_seen);

1885

1364

if(ret == -1){

1886

1365

perror_plus("clock_gettime");

1887

1366

return -1;

1888

1367

}

1889

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

1368

mc.current_server = mc.current_server->next;

1890

1369

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

1891

1370

servers, but don't block */

1892

1371

}

1894

1373

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

1895

1374

}

1896

1375

if(ret != 0){

1897

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

1376

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

1898

1377

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

1899

1378

}

1900

1379

}

1901

1380

}

1902

1381

}

1903

1382

1904

__attribute__((nonnull))

1905

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

1383

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

1906

1384

const float delay){

1907

struct dirent **direntries = NULL;

1908

if(hookdir_fd == -1){

1909

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1910

| O_CLOEXEC);

1911

if(hookdir_fd == -1){

1912

if(errno == ENOENT){

1913

if(debug){

1914

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

1915

" found\n", hookdir);

1916

}

1917

} else {

1918

perror_plus("open");

1919

}

1920

return;

1921

}

1922

}

1923

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

1924

runnable_hook, alphasort);

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1925

1390

if(numhooks == -1){

1926

1391

perror_plus("scandir");

1927

return;

1928

}

1929

struct dirent *direntry;

1930

int ret;

1931

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

1932

if(devnull == -1){

1933

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

1934

return;

1935

}

1936

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

1937

direntry = direntries[i];

1938

if(debug){

1939

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

1940

direntry->d_name);

1941

}

1942

pid_t hook_pid = fork();

1943

if(hook_pid == 0){

1944

/* Child */

1945

/* Raise privileges */

1946

errno = raise_privileges_permanently();

1947

if(errno != 0){

1948

perror_plus("Failed to raise privileges");

1949

_exit(EX_NOPERM);

1950

}

1951

/* Set group */

1952

errno = 0;

1953

ret = setgid(0);

1954

if(ret == -1){

1955

perror_plus("setgid");

1956

_exit(EX_NOPERM);

1957

}

1958

/* Reset supplementary groups */

1959

errno = 0;

1960

ret = setgroups(0, NULL);

1961

if(ret == -1){

1962

perror_plus("setgroups");

1963

_exit(EX_NOPERM);

1964

}

1965

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

1966

if(ret == -1){

1967

perror_plus("setenv");

1968

_exit(EX_OSERR);

1969

}

1970

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

1971

if(ret == -1){

1972

perror_plus("setenv");

1973

_exit(EX_OSERR);

1974

}

1975

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

1976

if(ret == -1){

1977

perror_plus("setenv");

1978

_exit(EX_OSERR);

1979

}

1980

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

1981

if(ret == -1){

1982

perror_plus("setenv");

1983

_exit(EX_OSERR);

1984

}

1985

char *delaystring;

1986

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

1987

if(ret == -1){

1392

} else {

1393

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

1394

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

1395

direntry = direntries[i];

1396

char *fullname = NULL;

1397

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

1398

if(ret < 0){

1988

1399

perror_plus("asprintf");

1989

_exit(EX_OSERR);

1990

}

1991

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

1992

if(ret == -1){

1400

continue;

1401

}

1402

if(debug){

1403

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

1404

direntry->d_name);

1405

}

1406

pid_t hook_pid = fork();

1407

if(hook_pid == 0){

1408

/* Child */

1409

dup2(devnull, STDIN_FILENO);

1410

close(devnull);

1411

dup2(STDERR_FILENO, STDOUT_FILENO);

1412

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

1413

if(ret == -1){

1414

perror_plus("setenv");

1415

_exit(EX_OSERR);

1416

}

1417

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

1418

if(ret == -1){

1419

perror_plus("setenv");

1420

_exit(EX_OSERR);

1421

}

1422

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

1423

if(ret == -1){

1424

perror_plus("setenv");

1425

_exit(EX_OSERR);

1426

}

1427

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

1428

if(ret == -1){

1429

perror_plus("setenv");

1430

_exit(EX_OSERR);

1431

}

1432

char *delaystring;

1433

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

1434

if(ret == -1){

1435

perror_plus("asprintf");

1436

_exit(EX_OSERR);

1437

}

1438

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

1439

if(ret == -1){

1440

free(delaystring);

1441

perror_plus("setenv");

1442

_exit(EX_OSERR);

1443

}

1993

1444

free(delaystring);

1994

perror_plus("setenv");

1995

_exit(EX_OSERR);

1996

}

1997

free(delaystring);

1998

if(connect_to != NULL){

1999

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

2000

if(ret == -1){

2001

perror_plus("setenv");

2002

_exit(EX_OSERR);

2003

}

2004

}

2005

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

2006

direntry->d_name,

2007

O_RDONLY));

2008

if(hook_fd == -1){

2009

perror_plus("openat");

2010

_exit(EXIT_FAILURE);

2011

}

2012

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

2013

perror_plus("close");

2014

_exit(EXIT_FAILURE);

2015

}

2016

ret = dup2(devnull, STDIN_FILENO);

2017

if(ret == -1){

2018

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

2019

_exit(EX_OSERR);

2020

}

2021

ret = close(devnull);

2022

if(ret == -1){

2023

perror_plus("close");

2024

_exit(EX_OSERR);

2025

}

2026

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2027

if(ret == -1){

2028

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

2029

_exit(EX_OSERR);

2030

}

2031

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

2032

environ) == -1){

2033

perror_plus("fexecve");

2034

_exit(EXIT_FAILURE);

2035

}

2036

} else {

2037

if(hook_pid == -1){

2038

perror_plus("fork");

2039

free(direntry);

2040

continue;

2041

}

2042

int status;

2043

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

2044

perror_plus("waitpid");

2045

free(direntry);

2046

continue;

2047

}

2048

if(WIFEXITED(status)){

2049

if(WEXITSTATUS(status) != 0){

2050

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

2051

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

2052

WEXITSTATUS(status));

2053

free(direntry);

2054

continue;

2055

}

2056

} else if(WIFSIGNALED(status)){

2057

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

2058

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

2059

WTERMSIG(status));

2060

free(direntry);

2061

continue;

2062

} else {

2063

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

2064

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

2065

free(direntry);

2066

continue;

2067

}

2068

}

2069

if(debug){

2070

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

2071

direntry->d_name);

2072

}

2073

free(direntry);

2074

}

2075

free(direntries);

2076

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

2077

perror_plus("close");

2078

} else {

2079

hookdir_fd = -1;

2080

}

2081

close(devnull);

2082

}

2083

2084

__attribute__((nonnull, warn_unused_result))

2085

int bring_up_interface(const char *const interface,

2086

const float delay){

2087

int old_errno = errno;

2088

int ret;

2089

struct ifreq network;

2090

unsigned int if_index = if_nametoindex(interface);

2091

if(if_index == 0){

2092

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

2093

errno = old_errno;

2094

return ENXIO;

2095

}

2096

2097

if(quit_now){

2098

errno = old_errno;

2099

return EINTR;

2100

}

2101

2102

if(not interface_is_up(interface)){

2103

int ret_errno = 0;

2104

int ioctl_errno = 0;

2105

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

2106

ret_errno = errno;

2107

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

2108

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

2109

errno = old_errno;

2110

return ret_errno;

2111

}

2112

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

2113

2114

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

2115

if(sd == -1){

2116

ret_errno = errno;

2117

perror_plus("socket");

2118

errno = old_errno;

2119

return ret_errno;

2120

}

2121

2122

if(quit_now){

2123

ret = close(sd);

2124

if(ret == -1){

2125

perror_plus("close");

2126

}

2127

errno = old_errno;

2128

return EINTR;

2129

}

2130

2131

if(debug){

2132

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

2133

interface);

2134

}

2135

2136

/* Raise privileges */

2137

ret_errno = raise_privileges();

2138

if(ret_errno != 0){

2139

errno = ret_errno;

2140

perror_plus("Failed to raise privileges");

2141

}

2142

2143

#ifdef __linux__

2144

int ret_linux;

2145

bool restore_loglevel = false;

2146

if(ret_errno == 0){

2147

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2148

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

2149

ret_linux = klogctl(8, NULL, 5);

2150

if(ret_linux == -1){

2151

perror_plus("klogctl");

2152

} else {

2153

restore_loglevel = true;

2154

}

2155

}

2156

#endif /* __linux__ */

2157

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

2158

ioctl_errno = errno;

2159

#ifdef __linux__

2160

if(restore_loglevel){

2161

ret_linux = klogctl(7, NULL, 0);

2162

if(ret_linux == -1){

2163

perror_plus("klogctl");

2164

}

2165

}

2166

#endif /* __linux__ */

2167

2168

/* If raise_privileges() succeeded above */

2169

if(ret_errno == 0){

2170

/* Lower privileges */

2171

ret_errno = lower_privileges();

2172

if(ret_errno != 0){

2173

errno = ret_errno;

2174

perror_plus("Failed to lower privileges");

2175

}

2176

}

2177

2178

/* Close the socket */

2179

ret = close(sd);

2180

if(ret == -1){

2181

perror_plus("close");

2182

}

2183

2184

if(ret_setflags == -1){

2185

errno = ioctl_errno;

2186

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2187

errno = old_errno;

2188

return ioctl_errno;

2189

}

2190

} else if(debug){

2191

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

2192

interface);

2193

}

2194

2195

/* Sleep checking until interface is running.

2196

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

2197

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

2198

if(interface_is_running(interface)){

2199

break;

2200

}

2201

struct timespec sleeptime = { .tv_nsec = 250000000 };

2202

ret = nanosleep(&sleeptime, NULL);

2203

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

2204

perror_plus("nanosleep");

2205

}

2206

}

2207

2208

errno = old_errno;

2209

return 0;

2210

}

2211

2212

__attribute__((nonnull, warn_unused_result))

2213

int take_down_interface(const char *const interface){

2214

int old_errno = errno;

2215

struct ifreq network;

2216

unsigned int if_index = if_nametoindex(interface);

2217

if(if_index == 0){

2218

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

2219

errno = old_errno;

2220

return ENXIO;

2221

}

2222

if(interface_is_up(interface)){

2223

int ret_errno = 0;

2224

int ioctl_errno = 0;

2225

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

2226

ret_errno = errno;

2227

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

2228

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

2229

errno = old_errno;

2230

return ret_errno;

2231

}

2232

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

2233

2234

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

2235

if(sd == -1){

2236

ret_errno = errno;

2237

perror_plus("socket");

2238

errno = old_errno;

2239

return ret_errno;

2240

}

2241

2242

if(debug){

2243

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

2244

interface);

2245

}

2246

2247

/* Raise privileges */

2248

ret_errno = raise_privileges();

2249

if(ret_errno != 0){

2250

errno = ret_errno;

2251

perror_plus("Failed to raise privileges");

2252

}

2253

2254

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

2255

ioctl_errno = errno;

2256

2257

/* If raise_privileges() succeeded above */

2258

if(ret_errno == 0){

2259

/* Lower privileges */

2260

ret_errno = lower_privileges();

2261

if(ret_errno != 0){

2262

errno = ret_errno;

2263

perror_plus("Failed to lower privileges");

2264

}

2265

}

2266

2267

/* Close the socket */

2268

int ret = close(sd);

2269

if(ret == -1){

2270

perror_plus("close");

2271

}

2272

2273

if(ret_setflags == -1){

2274

errno = ioctl_errno;

2275

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2276

errno = old_errno;

2277

return ioctl_errno;

2278

}

2279

} else if(debug){

2280

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

2281

interface);

2282

}

2283

2284

errno = old_errno;

2285

return 0;

1445

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

1446

perror_plus("execl");

1447

} else {

1448

int status;

1449

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

1450

perror_plus("waitpid");

1451

free(fullname);

1452

continue;

1453

}

1454

if(WIFEXITED(status)){

1455

if(WEXITSTATUS(status) != 0){

1456

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

1457

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

1458

WEXITSTATUS(status));

1459

free(fullname);

1460

continue;

1461

}

1462

} else if(WIFSIGNALED(status)){

1463

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

1464

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

1465

WTERMSIG(status));

1466

free(fullname);

1467

continue;

1468

} else {

1469

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

1470

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

1471

free(fullname);

1472

continue;

1473

}

1474

}

1475

free(fullname);

1476

if(debug){

1477

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

1478

direntry->d_name);

1479

}

1480

}

1481

close(devnull);

1482

}

1483

return true;

2286

1484

}

2287

1485

2288

1486

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

2289

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

2290

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

2291

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

2292

.current_server = NULL, .interfaces = NULL,

2293

.interfaces_size = 0 };

2294

1487

AvahiSServiceBrowser *sb = NULL;

2295

error_t ret_errno;

1488

int error;

2296

1489

int ret;

2297

1490

intmax_t tmpmax;

2298

1491

char *tmp;

2299

1492

int exitcode = EXIT_SUCCESS;

2300

char *interfaces_to_take_down = NULL;

2301

size_t interfaces_to_take_down_size = 0;

2302

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

2303

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

2304

char *tempdir = NULL;

1493

const char *interface = "";

1494

struct ifreq network;

1495

int sd = -1;

1496

bool take_down_interface = false;

1497

uid_t uid;

1498

gid_t gid;

1499

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

1500

bool tempdir_created = false;

2305

1501

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2306

1502

const char *seckey = PATHDIR "/" SECKEY;

2307

1503

const char *pubkey = PATHDIR "/" PUBKEY;

2308

const char *dh_params_file = NULL;

2309

char *interfaces_hooks = NULL;

2310

1504

2311

1505

bool gnutls_initialized = false;

2312

1506

bool gpgme_initialized = false;

2364

1558

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

2365

1559

" Diffie-Hellman key exchange",

2366

1560

.group = 2 },

2367

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

2368

.arg = "FILE",

2369

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

2370

" for the Diffie-Hellman key exchange",

2371

.group = 2 },

2372

1561

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

2373

1562

.arg = "STRING",

2374

1563

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

2379

1568

.group = 2 },

2380

1569

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

2381

1570

.arg = "SECONDS",

2382

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

1571

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

2383

1572

.group = 2 },

2384

1573

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

2385

1574

.arg = "DIR",

2408

1597

connect_to = arg;

2409

1598

break;

2410

1599

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

2411

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

2412

arg, (int)',');

2413

if(ret_errno != 0){

2414

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

2415

}

1600

interface = arg;

2416

1601

break;

2417

1602

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

2418

1603

seckey = arg;

2429

1614

}

2430

1615

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

2431

1616

break;

2432

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

2433

dh_params_file = arg;

2434

break;

2435

1617

case 130: /* --priority */

2436

1618

mc.priority = arg;

2437

1619

break;

2464

1646

argp_state_help(state, state->out_stream,

2465

1647

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2466

1648

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

2467

1651

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

2468

1652

exit(argp_err_exit_status);

2469

1653

break;

2477

1661

.args_doc = "",

2478

1662

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

2479

1663

" passwords from a Mandos server" };

2480

ret_errno = argp_parse(&argp, argc, argv,

2481

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2482

switch(ret_errno){

1664

ret = argp_parse(&argp, argc, argv,

1665

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1666

switch(ret){

2483

1667

case 0:

2484

1668

break;

2485

1669

case ENOMEM:

2486

1670

default:

2487

errno = ret_errno;

1671

errno = ret;

2488

1672

perror_plus("argp_parse");

2489

1673

exitcode = EX_OSERR;

2490

1674

goto end;

2493

1677

goto end;

2494

1678

}

2495

1679

}

2496

2497

{

1680

1681

if(getuid() == 0){

2498

1682

/* Work around Debian bug #633582:

2499

1683

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

2500

2501

/* Re-raise privileges */

2502

ret = raise_privileges();

2503

if(ret != 0){

2504

errno = ret;

2505

perror_plus("Failed to raise privileges");

2506

} else {

2507

struct stat st;

2508

2509

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

2510

int seckey_fd = open(seckey, O_RDONLY);

2511

if(seckey_fd == -1){

2512

perror_plus("open");

2513

} else {

2514

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

2515

if(ret == -1){

2516

perror_plus("fstat");

2517

} else {

2518

if(S_ISREG(st.st_mode)

2519

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

2520

ret = fchown(seckey_fd, uid, gid);

2521

if(ret == -1){

2522

perror_plus("fchown");

2523

}

2524

}

2525

}

2526

close(seckey_fd);

2527

}

2528

}

2529

2530

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

2531

int pubkey_fd = open(pubkey, O_RDONLY);

2532

if(pubkey_fd == -1){

2533

perror_plus("open");

2534

} else {

2535

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

2536

if(ret == -1){

2537

perror_plus("fstat");

2538

} else {

2539

if(S_ISREG(st.st_mode)

2540

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

2541

ret = fchown(pubkey_fd, uid, gid);

2542

if(ret == -1){

2543

perror_plus("fchown");

2544

}

2545

}

2546

}

2547

close(pubkey_fd);

2548

}

2549

}

2550

2551

if(dh_params_file != NULL

2552

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

2553

int dhparams_fd = open(dh_params_file, O_RDONLY);

2554

if(dhparams_fd == -1){

2555

perror_plus("open");

2556

} else {

2557

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

2558

if(ret == -1){

2559

perror_plus("fstat");

2560

} else {

2561

if(S_ISREG(st.st_mode)

2562

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

2563

ret = fchown(dhparams_fd, uid, gid);

2564

if(ret == -1){

2565

perror_plus("fchown");

2566

}

2567

}

2568

}

2569

close(dhparams_fd);

2570

}

2571

}

2572

2573

/* Lower privileges */

2574

ret = lower_privileges();

2575

if(ret != 0){

2576

errno = ret;

2577

perror_plus("Failed to lower privileges");

2578

}

2579

}

2580

}

2581

2582

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

2583

{

2584

char *interface = NULL;

2585

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

2586

interface))){

2587

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

2588

and if_nametoindex(interface) == 0){

2589

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

2590

fprintf_plus(stderr, "Not using nonexisting interface"

2591

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

2592

}

2593

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

2594

interface = NULL;

2595

}

1684

struct stat st;

1685

1686

/* Re-raise priviliges */

1687

errno = 0;

1688

ret = seteuid(0);

1689

if(ret == -1){

1690

perror_plus("seteuid");

1691

}

1692

1693

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

1694

int seckey_fd = open(seckey, O_RDONLY);

1695

if(seckey_fd == -1){

1696

perror_plus("open");

1697

} else {

1698

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

1699

if(ret == -1){

1700

perror_plus("fstat");

1701

} else {

1702

if(S_ISREG(st.st_mode)

1703

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

1704

ret = fchown(seckey_fd, uid, gid);

1705

if(ret == -1){

1706

perror_plus("fchown");

1707

}

1708

}

1709

}

1710

TEMP_FAILURE_RETRY(close(seckey_fd));

1711

}

1712

}

1713

1714

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

1715

int pubkey_fd = open(pubkey, O_RDONLY);

1716

if(pubkey_fd == -1){

1717

perror_plus("open");

1718

} else {

1719

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

1720

if(ret == -1){

1721

perror_plus("fstat");

1722

} else {

1723

if(S_ISREG(st.st_mode)

1724

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

1725

ret = fchown(pubkey_fd, uid, gid);

1726

if(ret == -1){

1727

perror_plus("fchown");

1728

}

1729

}

1730

}

1731

TEMP_FAILURE_RETRY(close(pubkey_fd));

1732

}

1733

}

1734

1735

/* Lower privileges */

1736

errno = 0;

1737

ret = seteuid(uid);

1738

if(ret == -1){

1739

perror_plus("seteuid");

2596

1740

}

2597

1741

}

2598

1742

2599

1743

/* Run network hooks */

2600

1744

{

2601

if(mc.interfaces != NULL){

2602

interfaces_hooks = malloc(mc.interfaces_size);

2603

if(interfaces_hooks == NULL){

2604

perror_plus("malloc");

2605

goto end;

2606

}

2607

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

2608

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

2609

}

2610

run_network_hooks("start", interfaces_hooks != NULL ?

2611

interfaces_hooks : "", delay);

1745

if(getuid() == 0){

1746

/* Re-raise priviliges */

1747

errno = 0;

1748

ret = seteuid(0);

1749

if(ret == -1){

1750

perror_plus("seteuid");

1751

}

1752

}

1753

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

1754

goto end;

1755

}

1756

if(getuid() == 0){

1757

/* Lower privileges */

1758

errno = 0;

1759

ret = seteuid(uid);

1760

if(ret == -1){

1761

perror_plus("seteuid");

1762

}

1763

}

2612

1764

}

2613

1765

2614

1766

if(not debug){

2615

1767

avahi_set_log_function(empty_log);

2616

1768

}

2617

1769

1770

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

1771

struct dirent **direntries;

1772

/* First look for interfaces that are up */

1773

ret = scandir(sys_class_net, &direntries, up_interface,

1774

alphasort);

1775

if(ret == 0){

1776

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

1777

free(direntries);

1778

ret = scandir(sys_class_net, &direntries, good_interface,

1779

alphasort);

1780

}

1781

if(ret >= 1){

1782

/* Pick the first interface returned */

1783

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

1784

if(debug){

1785

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

1786

}

1787

if(interface == NULL){

1788

perror_plus("malloc");

1789

free(direntries);

1790

exitcode = EXIT_FAILURE;

1791

goto end;

1792

}

1793

free(direntries);

1794

} else {

1795

free(direntries);

1796

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

1797

exitcode = EXIT_FAILURE;

1798

goto end;

1799

}

1800

}

1801

2618

1802

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

2619

1803

from the signal handler */

2620

1804

/* Initialize the pseudo-RNG for Avahi */

2621

1805

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

2622

simple_poll = avahi_simple_poll_new();

2623

if(simple_poll == NULL){

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2624

1808

fprintf_plus(stderr,

2625

1809

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

2626

1810

exitcode = EX_UNAVAILABLE;

2690

1874

}

2691

1875

}

2692

1876

2693

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

2694

if(mc.interfaces == NULL){

2695

struct dirent **direntries = NULL;

2696

/* Look for any good interfaces */

2697

ret = scandir(sys_class_net, &direntries, good_interface,

2698

alphasort);

2699

if(ret >= 1){

2700

/* Add all found interfaces to interfaces list */

2701

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

2702

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

2703

direntries[i]->d_name);

2704

if(ret_errno != 0){

2705

errno = ret_errno;

2706

perror_plus("argz_add");

2707

free(direntries[i]);

2708

continue;

2709

}

2710

if(debug){

2711

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

2712

direntries[i]->d_name);

2713

}

2714

free(direntries[i]);

2715

}

2716

free(direntries);

2717

} else {

2718

if(ret == 0){

2719

free(direntries);

2720

}

2721

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

2722

exitcode = EXIT_FAILURE;

2723

goto end;

2724

}

2725

}

2726

2727

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

2728

{

2729

char *interface = NULL;

2730

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

2731

interface))){

2732

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

2733

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

2734

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

2735

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

2736

interface);

2737

interface = NULL;

2738

while((interface = argz_next(mc.interfaces,

2739

mc.interfaces_size, interface))){

2740

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

2741

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

2742

interface);

2743

interface = NULL;

1877

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

1878

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

1879

if_index = (AvahiIfIndex) if_nametoindex(interface);

1880

if(if_index == 0){

1881

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

1882

exitcode = EX_UNAVAILABLE;

1883

goto end;

1884

}

1885

1886

if(quit_now){

1887

goto end;

1888

}

1889

1890

/* Re-raise priviliges */

1891

errno = 0;

1892

ret = seteuid(0);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

1897

#ifdef __linux__

1898

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1899

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

1900

ret = klogctl(8, NULL, 5);

1901

bool restore_loglevel = true;

1902

if(ret == -1){

1903

restore_loglevel = false;

1904

perror_plus("klogctl");

1905

}

1906

#endif /* __linux__ */

1907

1908

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1909

if(sd < 0){

1910

perror_plus("socket");

1911

exitcode = EX_OSERR;

1912

#ifdef __linux__

1913

if(restore_loglevel){

1914

ret = klogctl(7, NULL, 0);

1915

if(ret == -1){

1916

perror_plus("klogctl");

1917

}

1918

}

1919

#endif /* __linux__ */

1920

/* Lower privileges */

1921

errno = 0;

1922

ret = seteuid(uid);

1923

if(ret == -1){

1924

perror_plus("seteuid");

1925

}

1926

goto end;

1927

}

1928

strcpy(network.ifr_name, interface);

1929

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

1930

if(ret == -1){

1931

perror_plus("ioctl SIOCGIFFLAGS");

1932

#ifdef __linux__

1933

if(restore_loglevel){

1934

ret = klogctl(7, NULL, 0);

1935

if(ret == -1){

1936

perror_plus("klogctl");

1937

}

1938

}

1939

#endif /* __linux__ */

1940

exitcode = EX_OSERR;

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

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

1950

network.ifr_flags |= IFF_UP;

1951

take_down_interface = true;

1952

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

1953

if(ret == -1){

1954

take_down_interface = false;

1955

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1956

exitcode = EX_OSERR;

1957

#ifdef __linux__

1958

if(restore_loglevel){

1959

ret = klogctl(7, NULL, 0);

1960

if(ret == -1){

1961

perror_plus("klogctl");

2744

1962

}

2745

1963

}

1964

#endif /* __linux__ */

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

}

1974

/* Sleep checking until interface is running.

1975

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

1976

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

1977

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

1978

if(ret == -1){

1979

perror_plus("ioctl SIOCGIFFLAGS");

1980

} else if(network.ifr_flags & IFF_RUNNING){

2746

1981

break;

2747

1982

}

2748

bool interface_was_up = interface_is_up(interface);

2749

errno = bring_up_interface(interface, delay);

2750

if(not interface_was_up){

2751

if(errno != 0){

2752

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

2753

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

2754

} else {

2755

errno = argz_add(&interfaces_to_take_down,

2756

&interfaces_to_take_down_size,

2757

interface);

2758

if(errno != 0){

2759

perror_plus("argz_add");

2760

}

2761

}

2762

}

2763

}

2764

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

2765

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

2766

}

2767

}

2768

2769

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

2770

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

2771

if(debug){

2772

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

2773

mc.interfaces);

2774

}

2775

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

1983

struct timespec sleeptime = { .tv_nsec = 250000000 };

1984

ret = nanosleep(&sleeptime, NULL);

1985

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

1986

perror_plus("nanosleep");

1987

}

1988

}

1989

if(not take_down_interface){

1990

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

1991

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

1992

if(ret == -1){

1993

perror_plus("close");

1994

}

1995

}

1996

#ifdef __linux__

1997

if(restore_loglevel){

1998

/* Restores kernel loglevel to default */

1999

ret = klogctl(7, NULL, 0);

2000

if(ret == -1){

2001

perror_plus("klogctl");

2002

}

2003

}

2004

#endif /* __linux__ */

2005

/* Lower privileges */

2006

errno = 0;

2007

/* Lower privileges */

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2011

}

2776

2012

}

2777

2013

2778

2014

if(quit_now){

2779

2015

goto end;

2780

2016

}

2781

2017

2782

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

2018

ret = init_gnutls_global(pubkey, seckey);

2783

2019

if(ret == -1){

2784

2020

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

2785

2021

exitcode = EX_UNAVAILABLE;

2792

2028

goto end;

2793

2029

}

2794

2030

2795

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

2796

tempdir = mkdtemp(run_tempdir);

2797

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

2798

if(debug){

2799

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

2800

run_tempdir, old_tempdir);

2801

}

2802

tempdir = mkdtemp(old_tempdir);

2803

}

2804

if(tempdir == NULL){

2031

if(mkdtemp(tempdir) == NULL){

2805

2032

perror_plus("mkdtemp");

2806

2033

goto end;

2807

2034

}

2035

tempdir_created = true;

2808

2036

2809

2037

if(quit_now){

2810

2038

goto end;

2811

2039

}

2812

2040

2813

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

2041

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

2814

2042

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

2815

2043

exitcode = EX_UNAVAILABLE;

2816

2044

goto end;

2826

2054

/* Connect directly, do not use Zeroconf */

2827

2055

/* (Mainly meant for debugging) */

2828

2056

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

2829

2830

2057

if(address == NULL){

2831

2058

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

2832

2059

exitcode = EX_USAGE;

2837

2064

goto end;

2838

2065

}

2839

2066

2840

in_port_t port;

2067

uint16_t port;

2841

2068

errno = 0;

2842

2069

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

2843

2070

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

2844

or tmpmax != (in_port_t)tmpmax){

2071

or tmpmax != (uint16_t)tmpmax){

2845

2072

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

2846

2073

exitcode = EX_USAGE;

2847

2074

goto end;

2848

2075

}

2849

2076

2850

2077

if(quit_now){

2851

2078

goto end;

2852

2079

}

2853

2080

2854

port = (in_port_t)tmpmax;

2081

port = (uint16_t)tmpmax;

2855

2082

*address = '\0';

2856

2083

/* Colon in address indicates IPv6 */

2857

2084

int af;

2873

2100

}

2874

2101

2875

2102

while(not quit_now){

2876

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

2877

&mc);

2103

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

2878

2104

if(quit_now or ret == 0){

2879

2105

break;

2880

2106

}

2882

2108

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

2883

2109

(int)retry_interval);

2884

2110

}

2885

sleep((unsigned int)retry_interval);

2111

sleep((int)retry_interval);

2886

2112

}

2887

2113

2888

if(not quit_now){

2114

if (not quit_now){

2889

2115

exitcode = EXIT_SUCCESS;

2890

2116

}

2891

2117

2906

2132

config.publish_domain = 0;

2907

2133

2908

2134

/* Allocate a new server */

2909

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2910

&config, NULL, NULL, &ret);

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2911

2138

2912

2139

/* Free the Avahi configuration data */

2913

2140

avahi_server_config_free(&config);

2916

2143

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

2917

2144

if(mc.server == NULL){

2918

2145

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

2919

avahi_strerror(ret));

2146

avahi_strerror(error));

2920

2147

exitcode = EX_UNAVAILABLE;

2921

2148

goto end;

2922

2149

}

2928

2155

/* Create the Avahi service browser */

2929

2156

sb = avahi_s_service_browser_new(mc.server, if_index,

2930

2157

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2931

NULL, 0, browse_callback,

2932

(void *)&mc);

2158

NULL, 0, browse_callback, NULL);

2933

2159

if(sb == NULL){

2934

2160

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

2935

2161

avahi_strerror(avahi_server_errno(mc.server)));

2946

2172

if(debug){

2947

2173

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

2948

2174

}

2949

2950

ret = avahi_loop_with_timeout(simple_poll,

2951

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

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2952

2178

if(debug){

2953

2179

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

2954

2180

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

2961

2187

}

2962

2188

2963

2189

/* Cleanup things */

2964

free(mc.interfaces);

2965

2966

2190

if(sb != NULL)

2967

2191

avahi_s_service_browser_free(sb);

2968

2192

2969

2193

if(mc.server != NULL)

2970

2194

avahi_server_free(mc.server);

2971

2195

2972

if(simple_poll != NULL)

2973

avahi_simple_poll_free(simple_poll);

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

2974

2198

2975

2199

if(gnutls_initialized){

2976

2200

gnutls_certificate_free_credentials(mc.cred);

2201

gnutls_global_deinit();

2977

2202

gnutls_dh_params_deinit(mc.dh_params);

2978

2203

}

2979

2204

2987

2212

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

2988

2213

while(mc.current_server != NULL){

2989

2214

server *next = mc.current_server->next;

2990

#ifdef __GNUC__

2991

#pragma GCC diagnostic push

2992

#pragma GCC diagnostic ignored "-Wcast-qual"

2993

#endif

2994

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

2995

#ifdef __GNUC__

2996

#pragma GCC diagnostic pop

2997

#endif

2998

2215

free(mc.current_server);

2999

2216

mc.current_server = next;

3000

2217

}

3001

2218

}

3002

2219

3003

/* Re-raise privileges */

2220

/* Re-raise priviliges */

3004

2221

{

3005

ret = raise_privileges();

3006

if(ret != 0){

3007

errno = ret;

3008

perror_plus("Failed to raise privileges");

3009

} else {

3010

3011

/* Run network hooks */

3012

run_network_hooks("stop", interfaces_hooks != NULL ?

3013

interfaces_hooks : "", delay);

3014

3015

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

3016

{

3017

char *interface = NULL;

3018

while((interface=argz_next(interfaces_to_take_down,

3019

interfaces_to_take_down_size,

3020

interface))){

3021

ret = take_down_interface(interface);

3022

if(ret != 0){

3023

errno = ret;

3024

perror_plus("Failed to take down interface");

3025

}

3026

}

3027

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

3028

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

3029

" down\n");

3030

}

3031

}

3032

}

3033

3034

ret = lower_privileges_permanently();

3035

if(ret != 0){

3036

errno = ret;

3037

perror_plus("Failed to lower privileges permanently");

3038

}

3039

}

3040

3041

free(interfaces_to_take_down);

3042

free(interfaces_hooks);

3043

3044

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

3045

uintmax_t level){

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

2227

}

2228

}

2229

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Take down the network interface */

2234

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

2235

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

2236

if(ret == -1){

2237

perror_plus("ioctl SIOCGIFFLAGS");

2238

} else if(network.ifr_flags & IFF_UP){

2239

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

2240

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

2241

if(ret == -1){

2242

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2243

}

2244

}

2245

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

2246

if(ret == -1){

2247

perror_plus("close");

2248

}

2249

}

2250

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

2258

}

2259

2260

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

2261

if(tempdir_created){

3046

2262

struct dirent **direntries = NULL;

3047

int dret;

3048

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

3049

O_RDONLY

3050

| O_NOFOLLOW

3051

| O_DIRECTORY

3052

| O_PATH));

3053

if(dir_fd == -1){

3054

perror_plus("open");

3055

}

3056

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

3057

notdotentries, alphasort);

3058

if(numentries >= 0){

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

3059

2267

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

3060

if(debug){

3061

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

3062

dirname, direntries[i]->d_name);

3063

}

3064

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

3065

if(dret == -1){

3066

if(errno == EISDIR){

3067

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

3068

AT_REMOVEDIR);

3069

}

3070

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

3071

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

3072

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

3073

/* Recurse only in this special case */

3074

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

3075

dret = 0;

3076

}

3077

if(dret == -1){

3078

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

3079

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

3080

}

3081

}

3082

free(direntries[i]);

3083

}

3084

3085

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

3086

free(direntries);

3087

if(numentries == -1){

3088

perror_plus("scandirat");

3089

}

3090

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3091

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

3092

perror_plus("rmdir");

3093

}

3094

} else {

3095

perror_plus("scandirat");

3096

}

3097

close(dir_fd);

3098

}

3099

3100

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

3101

if(tempdir != NULL){

3102

clean_dir_at(-1, tempdir, 0);

2268

direntry = direntries[i];

2269

char *fullname = NULL;

2270

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

2271

direntry->d_name);

2272

if(ret < 0){

2273

perror_plus("asprintf");

2274

continue;

2275

}

2276

ret = remove(fullname);

2277

if(ret == -1){

2278

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

2279

strerror(errno));

2280

}

2281

free(fullname);

2282

}

2283

}

2284

2285

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

2286

free(direntries);

2287

if (numentries == -1){

2288

perror_plus("scandir");

2289

}

2290

ret = rmdir(tempdir);

2291

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

2292

perror_plus("rmdir");

2293

}

3103

2294

}

3104

2295

3105

2296

if(quit_now){