/mandos/release : revision 237.16.11

9

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

10

*

11

* 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

16

* 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

39

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() */

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#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

62

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

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63

strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

64

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

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

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66

program_invocation_short_name */

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

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

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73

*/

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74

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

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

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

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unlinkat() */

82

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

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setgid(), pause() */

77

#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

85

80

argp_state, struct argp,

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87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

93

88

#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(),

99

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;

173

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,

163

.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);

188

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

error_t raise_privileges(void){

821

error_t old_errno = errno;

822

error_t ret_errno = 0;

823

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

824

ret_errno = errno;

825

}

826

errno = old_errno;

827

return ret_errno;

828

}

829

830

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

831

__attribute__((warn_unused_result))

832

error_t raise_privileges_permanently(void){

833

error_t old_errno = errno;

834

error_t ret_errno = raise_privileges();

835

if(ret_errno != 0){

836

errno = old_errno;

837

return ret_errno;

838

}

839

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

840

ret_errno = errno;

841

}

842

errno = old_errno;

843

return ret_errno;

844

}

845

846

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

847

__attribute__((warn_unused_result))

848

error_t lower_privileges(void){

849

error_t old_errno = errno;

850

error_t ret_errno = 0;

851

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

852

ret_errno = errno;

853

}

854

errno = old_errno;

855

return ret_errno;

856

}

857

858

/* Lower privileges permanently */

859

__attribute__((warn_unused_result))

860

error_t lower_privileges_permanently(void){

861

error_t old_errno = errno;

862

error_t ret_errno = 0;

863

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

864

ret_errno = errno;

865

}

866

errno = old_errno;

867

return ret_errno;

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

935

written = 0;

1452

961

1453

962

mandos_end:

1454

963

{

1455

if(route_added){

1456

if(not delete_local_route(ip, if_index)){

1457

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

1458

" interface %d", ip, if_index);

1459

}

1460

}

1461

964

int e = errno;

1462

965

free(decrypted_buffer);

1463

966

free(buffer);

1464

967

if(tcp_sd >= 0){

1465

ret = close(tcp_sd);

968

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

1466

969

}

1467

970

if(ret == -1){

1468

971

if(e == 0){

1480

983

return retval;

1481

984

}

1482

985

1483

__attribute__((nonnull))

1484

986

static void resolve_callback(AvahiSServiceResolver *r,

1485

987

AvahiIfIndex interface,

1486

988

AvahiProtocol proto,

1494

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1495

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1496

998

flags,

1497

void *mc){

1498

if(r == NULL){

1499

return;

1500

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1501

1001

1502

1002

/* Called whenever a service has been resolved successfully or

1503

1003

timed out */

1504

1004

1505

1005

if(quit_now){

1506

avahi_s_service_resolver_free(r);

1507

1006

return;

1508

1007

}

1509

1008

1513

1012

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

1514

1013

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

1515

1014

domain,

1516

avahi_strerror(avahi_server_errno

1517

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1518

1016

break;

1519

1017

1520

1018

case AVAHI_RESOLVER_FOUND:

1526

1024

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

1527

1025

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

1528

1026

}

1529

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

1530

interface,

1531

avahi_proto_to_af(proto),

1532

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1533

1029

if(ret == 0){

1534

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1535

1031

} else {

1536

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

1537

avahi_proto_to_af(proto),

1538

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

1539

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

1540

" list\n", name);

1541

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1542

1034

}

1543

1035

}

1544

1036

}

1554

1046

const char *domain,

1555

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1556

1048

flags,

1557

void *mc){

1558

if(b == NULL){

1559

return;

1560

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1561

1051

1562

1052

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

1563

1053

is removed from the LAN */

1571

1061

case AVAHI_BROWSER_FAILURE:

1572

1062

1573

1063

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

1574

avahi_strerror(avahi_server_errno

1575

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

1576

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1577

1066

return;

1578

1067

1579

1068

case AVAHI_BROWSER_NEW:

1582

1071

the callback function is called the Avahi server will free the

1583

1072

resolver for us. */

1584

1073

1585

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

1586

interface, protocol, name, type,

1587

domain, protocol, 0,

1588

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)

1589

1077

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

1590

1078

" %s\n", name,

1591

avahi_strerror(avahi_server_errno

1592

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1593

1080

break;

1594

1081

1595

1082

case AVAHI_BROWSER_REMOVE:

1614

1101

signal_received = sig;

1615

1102

int old_errno = errno;

1616

1103

/* set main loop to exit */

1617

if(simple_poll != NULL){

1618

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1619

1106

}

1620

1107

errno = old_errno;

1621

1108

}

1622

1109

1623

__attribute__((nonnull, warn_unused_result))

1624

1110

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

1625

1111

int ret;

1626

error_t ret_errno;

1627

1112

1628

1113

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

1629

1114

if(s < 0){

1630

ret_errno = errno;

1631

1115

perror_plus("socket");

1632

errno = ret_errno;

1633

1116

return false;

1634

1117

}

1635

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

1636

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

1118

strcpy(ifr->ifr_name, ifname);

1637

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1638

1120

if(ret == -1){

1639

1121

if(debug){

1640

ret_errno = errno;

1641

1122

perror_plus("ioctl SIOCGIFFLAGS");

1642

errno = ret_errno;

1643

1123

}

1644

1124

return false;

1645

1125

}

1646

1126

return true;

1647

1127

}

1648

1128

1649

__attribute__((nonnull, warn_unused_result))

1650

1129

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

1651

1130

1652

1131

/* Reject the loopback device */

1694

1173

* corresponds to an acceptable network device.

1695

1174

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

1696

1175

*/

1697

__attribute__((nonnull, warn_unused_result))

1698

1176

int good_interface(const struct dirent *if_entry){

1699

1177

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

1700

1178

return 0;

1716

1194

}

1717

1195

1718

1196

/*

1719

* This function determines if a network interface is up.

1720

*/

1721

__attribute__((nonnull, warn_unused_result))

1722

bool interface_is_up(const char *interface){

1723

struct ifreq ifr;

1724

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

1725

if(debug){

1726

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

1727

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

1728

}

1729

return false;

1730

}

1731

1732

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

1733

}

1734

1735

/*

1736

* This function determines if a network interface is running

1737

*/

1738

__attribute__((nonnull, warn_unused_result))

1739

bool interface_is_running(const char *interface){

1740

struct ifreq ifr;

1741

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

1742

if(debug){

1743

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

1744

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

1745

}

1746

return false;

1747

}

1748

1749

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

1750

}

1751

1752

__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

1753

1239

int notdotentries(const struct dirent *direntry){

1754

1240

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

1755

1241

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

1762

1248

}

1763

1249

1764

1250

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

1765

__attribute__((nonnull, warn_unused_result))

1766

1251

int runnable_hook(const struct dirent *direntry){

1767

1252

int ret;

1768

1253

size_t sret;

1776

1261

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

1777

1262

"abcdefghijklmnopqrstuvwxyz"

1778

1263

"0123456789"

1779

"_.-");

1264

"_-");

1780

1265

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

1781

1266

/* Contains non-allowed characters */

1782

1267

if(debug){

1786

1271

return 0;

1787

1272

}

1788

1273

1789

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);

1790

1282

if(ret == -1){

1791

1283

if(debug){

1792

1284

perror_plus("Could not stat hook");

1809

1301

}

1810

1302

return 0;

1811

1303

}

1812

if(debug){

1813

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1814

direntry->d_name);

1815

}

1816

1304

return 1;

1817

1305

}

1818

1306

1819

__attribute__((nonnull, warn_unused_result))

1820

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1821

mandos_context *mc){

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1822

1308

int ret;

1823

1309

struct timespec now;

1824

1310

struct timespec waited_time;

1825

1311

intmax_t block_time;

1826

1312

1827

1313

while(true){

1828

if(mc->current_server == NULL){

1829

if(debug){

1314

if(mc.current_server == NULL){

1315

if (debug){

1830

1316

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

1831

1317

" No timeout!\n");

1832

1318

}

1833

1319

ret = avahi_simple_poll_iterate(s, -1);

1834

1320

} else {

1835

if(debug){

1321

if (debug){

1836

1322

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

1837

1323

" it, or wait\n");

1838

1324

}

1845

1331

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

1846

1332

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

1847

1333

waited_time.tv_sec = (now.tv_sec

1848

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

1334

- mc.current_server->last_seen.tv_sec);

1849

1335

waited_time.tv_nsec = (now.tv_nsec

1850

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

1336

- mc.current_server->last_seen.tv_nsec);

1851

1337

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

1852

1338

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

1853

1339

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

1855

1341

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

1856

1342

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

1857

1343

1858

if(debug){

1344

if (debug){

1859

1345

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

1860

1346

block_time);

1861

1347

}

1862

1348

1863

1349

if(block_time <= 0){

1864

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

1865

mc->current_server->port,

1866

mc->current_server->if_index,

1867

mc->current_server->af, mc);

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

1868

1354

if(ret == 0){

1869

avahi_simple_poll_quit(s);

1355

avahi_simple_poll_quit(mc.simple_poll);

1870

1356

return 0;

1871

1357

}

1872

1358

ret = clock_gettime(CLOCK_MONOTONIC,

1873

&mc->current_server->last_seen);

1359

&mc.current_server->last_seen);

1874

1360

if(ret == -1){

1875

1361

perror_plus("clock_gettime");

1876

1362

return -1;

1877

1363

}

1878

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

1364

mc.current_server = mc.current_server->next;

1879

1365

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

1880

1366

servers, but don't block */

1881

1367

}

1883

1369

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

1884

1370

}

1885

1371

if(ret != 0){

1886

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

1372

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

1887

1373

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

1888

1374

}

1889

1375

}

1890

1376

}

1891

1377

}

1892

1378

1893

__attribute__((nonnull))

1894

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

1379

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

1895

1380

const float delay){

1896

struct dirent **direntries = NULL;

1897

if(hookdir_fd == -1){

1898

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1899

| O_CLOEXEC);

1900

if(hookdir_fd == -1){

1901

if(errno == ENOENT){

1902

if(debug){

1903

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

1904

" found\n", hookdir);

1905

}

1906

} else {

1907

perror_plus("open");

1908

}

1909

return;

1910

}

1911

}

1912

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

1913

runnable_hook, alphasort);

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

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

1385

alphasort);

1914

1386

if(numhooks == -1){

1915

1387

perror_plus("scandir");

1916

return;

1917

}

1918

struct dirent *direntry;

1919

int ret;

1920

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

1921

if(devnull == -1){

1922

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

1923

return;

1924

}

1925

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

1926

direntry = direntries[i];

1927

if(debug){

1928

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

1929

direntry->d_name);

1930

}

1931

pid_t hook_pid = fork();

1932

if(hook_pid == 0){

1933

/* Child */

1934

/* Raise privileges */

1935

errno = raise_privileges_permanently();

1936

if(errno != 0){

1937

perror_plus("Failed to raise privileges");

1938

_exit(EX_NOPERM);

1939

}

1940

/* Set group */

1941

errno = 0;

1942

ret = setgid(0);

1943

if(ret == -1){

1944

perror_plus("setgid");

1945

_exit(EX_NOPERM);

1946

}

1947

/* Reset supplementary groups */

1948

errno = 0;

1949

ret = setgroups(0, NULL);

1950

if(ret == -1){

1951

perror_plus("setgroups");

1952

_exit(EX_NOPERM);

1953

}

1954

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

1955

if(ret == -1){

1956

perror_plus("setenv");

1957

_exit(EX_OSERR);

1958

}

1959

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

1960

if(ret == -1){

1961

perror_plus("setenv");

1962

_exit(EX_OSERR);

1963

}

1964

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

1965

if(ret == -1){

1966

perror_plus("setenv");

1967

_exit(EX_OSERR);

1968

}

1969

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

1970

if(ret == -1){

1971

perror_plus("setenv");

1972

_exit(EX_OSERR);

1973

}

1974

char *delaystring;

1975

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

1976

if(ret == -1){

1388

} else {

1389

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

1390

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

1391

direntry = direntries[i];

1392

char *fullname = NULL;

1393

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

1394

if(ret < 0){

1977

1395

perror_plus("asprintf");

1978

_exit(EX_OSERR);

1979

}

1980

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

1981

if(ret == -1){

1396

continue;

1397

}

1398

if(debug){

1399

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

1400

direntry->d_name);

1401

}

1402

pid_t hook_pid = fork();

1403

if(hook_pid == 0){

1404

/* Child */

1405

dup2(devnull, STDIN_FILENO);

1406

close(devnull);

1407

dup2(STDERR_FILENO, STDOUT_FILENO);

1408

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

1409

if(ret == -1){

1410

perror_plus("setenv");

1411

return false;

1412

}

1413

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

1414

if(ret == -1){

1415

perror_plus("setenv");

1416

return false;

1417

}

1418

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

1419

if(ret == -1){

1420

perror_plus("setenv");

1421

return false;

1422

}

1423

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

1424

if(ret == -1){

1425

perror_plus("setenv");

1426

return false;

1427

}

1428

char *delaystring;

1429

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

1430

if(ret == -1){

1431

perror_plus("asprintf");

1432

return false;

1433

}

1434

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

1435

if(ret == -1){

1436

free(delaystring);

1437

perror_plus("setenv");

1438

return false;

1439

}

1982

1440

free(delaystring);

1983

perror_plus("setenv");

1984

_exit(EX_OSERR);

1985

}

1986

free(delaystring);

1987

if(connect_to != NULL){

1988

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

1989

if(ret == -1){

1990

perror_plus("setenv");

1991

_exit(EX_OSERR);

1992

}

1993

}

1994

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

1995

direntry->d_name,

1996

O_RDONLY));

1997

if(hook_fd == -1){

1998

perror_plus("openat");

1999

_exit(EXIT_FAILURE);

2000

}

2001

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

2002

perror_plus("close");

2003

_exit(EXIT_FAILURE);

2004

}

2005

ret = dup2(devnull, STDIN_FILENO);

2006

if(ret == -1){

2007

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

2008

_exit(EX_OSERR);

2009

}

2010

ret = close(devnull);

2011

if(ret == -1){

2012

perror_plus("close");

2013

_exit(EX_OSERR);

2014

}

2015

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2016

if(ret == -1){

2017

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

2018

_exit(EX_OSERR);

2019

}

2020

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

2021

environ) == -1){

2022

perror_plus("fexecve");

2023

_exit(EXIT_FAILURE);

2024

}

2025

} else {

2026

if(hook_pid == -1){

2027

perror_plus("fork");

2028

free(direntry);

2029

continue;

2030

}

2031

int status;

2032

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

2033

perror_plus("waitpid");

2034

free(direntry);

2035

continue;

2036

}

2037

if(WIFEXITED(status)){

2038

if(WEXITSTATUS(status) != 0){

2039

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

2040

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

2041

WEXITSTATUS(status));

2042

free(direntry);

2043

continue;

2044

}

2045

} else if(WIFSIGNALED(status)){

2046

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

2047

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

2048

WTERMSIG(status));

2049

free(direntry);

2050

continue;

2051

} else {

2052

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

2053

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

2054

free(direntry);

2055

continue;

2056

}

2057

}

2058

if(debug){

2059

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

2060

direntry->d_name);

2061

}

2062

free(direntry);

2063

}

2064

free(direntries);

2065

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

2066

perror_plus("close");

2067

} else {

2068

hookdir_fd = -1;

2069

}

2070

close(devnull);

2071

}

2072

2073

__attribute__((nonnull, warn_unused_result))

2074

error_t bring_up_interface(const char *const interface,

2075

const float delay){

2076

error_t old_errno = errno;

2077

int ret;

2078

struct ifreq network;

2079

unsigned int if_index = if_nametoindex(interface);

2080

if(if_index == 0){

2081

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

2082

errno = old_errno;

2083

return ENXIO;

2084

}

2085

2086

if(quit_now){

2087

errno = old_errno;

2088

return EINTR;

2089

}

2090

2091

if(not interface_is_up(interface)){

2092

error_t ret_errno = 0, ioctl_errno = 0;

2093

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

2094

ret_errno = errno;

2095

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

2096

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

2097

errno = old_errno;

2098

return ret_errno;

2099

}

2100

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

2101

2102

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

2103

if(sd == -1){

2104

ret_errno = errno;

2105

perror_plus("socket");

2106

errno = old_errno;

2107

return ret_errno;

2108

}

2109

2110

if(quit_now){

2111

ret = close(sd);

2112

if(ret == -1){

2113

perror_plus("close");

2114

}

2115

errno = old_errno;

2116

return EINTR;

2117

}

2118

2119

if(debug){

2120

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

2121

interface);

2122

}

2123

2124

/* Raise privileges */

2125

ret_errno = raise_privileges();

2126

if(ret_errno != 0){

2127

errno = ret_errno;

2128

perror_plus("Failed to raise privileges");

2129

}

2130

2131

#ifdef __linux__

2132

int ret_linux;

2133

bool restore_loglevel = false;

2134

if(ret_errno == 0){

2135

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2136

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

2137

ret_linux = klogctl(8, NULL, 5);

2138

if(ret_linux == -1){

2139

perror_plus("klogctl");

2140

} else {

2141

restore_loglevel = true;

2142

}

2143

}

2144

#endif /* __linux__ */

2145

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

2146

ioctl_errno = errno;

2147

#ifdef __linux__

2148

if(restore_loglevel){

2149

ret_linux = klogctl(7, NULL, 0);

2150

if(ret_linux == -1){

2151

perror_plus("klogctl");

2152

}

2153

}

2154

#endif /* __linux__ */

2155

2156

/* If raise_privileges() succeeded above */

2157

if(ret_errno == 0){

2158

/* Lower privileges */

2159

ret_errno = lower_privileges();

2160

if(ret_errno != 0){

2161

errno = ret_errno;

2162

perror_plus("Failed to lower privileges");

2163

}

2164

}

2165

2166

/* Close the socket */

2167

ret = close(sd);

2168

if(ret == -1){

2169

perror_plus("close");

2170

}

2171

2172

if(ret_setflags == -1){

2173

errno = ioctl_errno;

2174

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2175

errno = old_errno;

2176

return ioctl_errno;

2177

}

2178

} else if(debug){

2179

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

2180

interface);

2181

}

2182

2183

/* Sleep checking until interface is running.

2184

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

2185

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

2186

if(interface_is_running(interface)){

2187

break;

2188

}

2189

struct timespec sleeptime = { .tv_nsec = 250000000 };

2190

ret = nanosleep(&sleeptime, NULL);

2191

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

2192

perror_plus("nanosleep");

2193

}

2194

}

2195

2196

errno = old_errno;

2197

return 0;

2198

}

2199

2200

__attribute__((nonnull, warn_unused_result))

2201

error_t take_down_interface(const char *const interface){

2202

error_t old_errno = errno;

2203

struct ifreq network;

2204

unsigned int if_index = if_nametoindex(interface);

2205

if(if_index == 0){

2206

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

2207

errno = old_errno;

2208

return ENXIO;

2209

}

2210

if(interface_is_up(interface)){

2211

error_t ret_errno = 0, ioctl_errno = 0;

2212

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

2213

ret_errno = errno;

2214

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

2215

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

2216

errno = old_errno;

2217

return ret_errno;

2218

}

2219

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

2220

2221

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

2222

if(sd == -1){

2223

ret_errno = errno;

2224

perror_plus("socket");

2225

errno = old_errno;

2226

return ret_errno;

2227

}

2228

2229

if(debug){

2230

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

2231

interface);

2232

}

2233

2234

/* Raise privileges */

2235

ret_errno = raise_privileges();

2236

if(ret_errno != 0){

2237

errno = ret_errno;

2238

perror_plus("Failed to raise privileges");

2239

}

2240

2241

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

2242

ioctl_errno = errno;

2243

2244

/* If raise_privileges() succeeded above */

2245

if(ret_errno == 0){

2246

/* Lower privileges */

2247

ret_errno = lower_privileges();

2248

if(ret_errno != 0){

2249

errno = ret_errno;

2250

perror_plus("Failed to lower privileges");

2251

}

2252

}

2253

2254

/* Close the socket */

2255

int ret = close(sd);

2256

if(ret == -1){

2257

perror_plus("close");

2258

}

2259

2260

if(ret_setflags == -1){

2261

errno = ioctl_errno;

2262

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2263

errno = old_errno;

2264

return ioctl_errno;

2265

}

2266

} else if(debug){

2267

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

2268

interface);

2269

}

2270

2271

errno = old_errno;

2272

return 0;

1441

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

1442

perror_plus("execl");

1443

} else {

1444

int status;

1445

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

1446

perror_plus("waitpid");

1447

free(fullname);

1448

continue;

1449

}

1450

if(WIFEXITED(status)){

1451

if(WEXITSTATUS(status) != 0){

1452

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

1453

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

1454

WEXITSTATUS(status));

1455

free(fullname);

1456

continue;

1457

}

1458

} else if(WIFSIGNALED(status)){

1459

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

1460

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

1461

WTERMSIG(status));

1462

free(fullname);

1463

continue;

1464

} else {

1465

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

1466

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

1467

free(fullname);

1468

continue;

1469

}

1470

}

1471

free(fullname);

1472

if(quit_now){

1473

break;

1474

}

1475

}

1476

close(devnull);

1477

}

1478

return true;

2273

1479

}

2274

1480

2275

1481

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

2276

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

2277

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

2278

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

2279

.current_server = NULL, .interfaces = NULL,

2280

.interfaces_size = 0 };

2281

1482

AvahiSServiceBrowser *sb = NULL;

2282

error_t ret_errno;

1483

int error;

2283

1484

int ret;

2284

1485

intmax_t tmpmax;

2285

1486

char *tmp;

2286

1487

int exitcode = EXIT_SUCCESS;

2287

char *interfaces_to_take_down = NULL;

2288

size_t interfaces_to_take_down_size = 0;

2289

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

2290

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

2291

char *tempdir = NULL;

1488

const char *interface = "";

1489

struct ifreq network;

1490

int sd = -1;

1491

bool take_down_interface = false;

1492

uid_t uid;

1493

gid_t gid;

1494

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

1495

bool tempdir_created = false;

2292

1496

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2293

1497

const char *seckey = PATHDIR "/" SECKEY;

2294

1498

const char *pubkey = PATHDIR "/" PUBKEY;

2295

const char *dh_params_file = NULL;

2296

char *interfaces_hooks = NULL;

2297

1499

2298

1500

bool gnutls_initialized = false;

2299

1501

bool gpgme_initialized = false;

2351

1553

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

2352

1554

" Diffie-Hellman key exchange",

2353

1555

.group = 2 },

2354

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

2355

.arg = "FILE",

2356

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

2357

" for the Diffie-Hellman key exchange",

2358

.group = 2 },

2359

1556

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

2360

1557

.arg = "STRING",

2361

1558

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

2366

1563

.group = 2 },

2367

1564

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

2368

1565

.arg = "SECONDS",

2369

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

1566

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

2370

1567

.group = 2 },

2371

1568

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

2372

1569

.arg = "DIR",

2395

1592

connect_to = arg;

2396

1593

break;

2397

1594

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

2398

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

2399

arg, (int)',');

2400

if(ret_errno != 0){

2401

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

2402

}

1595

interface = arg;

2403

1596

break;

2404

1597

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

2405

1598

seckey = arg;

2416

1609

}

2417

1610

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

2418

1611

break;

2419

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

2420

dh_params_file = arg;

2421

break;

2422

1612

case 130: /* --priority */

2423

1613

mc.priority = arg;

2424

1614

break;

2451

1641

argp_state_help(state, state->out_stream,

2452

1642

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2453

1643

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

1644

fprintf_plus(state->out_stream,

1645

"Mandos plugin mandos-client: ");

2454

1646

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

2455

1647

exit(argp_err_exit_status);

2456

1648

break;

2480

1672

goto end;

2481

1673

}

2482

1674

}

2483

2484

{

1675

1676

if(getuid() == 0){

2485

1677

/* Work around Debian bug #633582:

2486

1678

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

2487

2488

/* Re-raise privileges */

2489

ret_errno = raise_privileges();

2490

if(ret_errno != 0){

2491

errno = ret_errno;

2492

perror_plus("Failed to raise privileges");

2493

} else {

2494

struct stat st;

2495

2496

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

2497

int seckey_fd = open(seckey, O_RDONLY);

2498

if(seckey_fd == -1){

2499

perror_plus("open");

2500

} else {

2501

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

2502

if(ret == -1){

2503

perror_plus("fstat");

2504

} else {

2505

if(S_ISREG(st.st_mode)

2506

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

2507

ret = fchown(seckey_fd, uid, gid);

2508

if(ret == -1){

2509

perror_plus("fchown");

2510

}

2511

}

2512

}

2513

close(seckey_fd);

2514

}

2515

}

2516

2517

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

2518

int pubkey_fd = open(pubkey, O_RDONLY);

2519

if(pubkey_fd == -1){

2520

perror_plus("open");

2521

} else {

2522

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

2523

if(ret == -1){

2524

perror_plus("fstat");

2525

} else {

2526

if(S_ISREG(st.st_mode)

2527

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

2528

ret = fchown(pubkey_fd, uid, gid);

2529

if(ret == -1){

2530

perror_plus("fchown");

2531

}

2532

}

2533

}

2534

close(pubkey_fd);

2535

}

2536

}

2537

2538

if(dh_params_file != NULL

2539

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

2540

int dhparams_fd = open(dh_params_file, O_RDONLY);

2541

if(dhparams_fd == -1){

2542

perror_plus("open");

2543

} else {

2544

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

2545

if(ret == -1){

2546

perror_plus("fstat");

2547

} else {

2548

if(S_ISREG(st.st_mode)

2549

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

2550

ret = fchown(dhparams_fd, uid, gid);

2551

if(ret == -1){

2552

perror_plus("fchown");

2553

}

2554

}

2555

}

2556

close(dhparams_fd);

2557

}

2558

}

2559

2560

/* Lower privileges */

2561

ret_errno = lower_privileges();

2562

if(ret_errno != 0){

2563

errno = ret_errno;

2564

perror_plus("Failed to lower privileges");

2565

}

2566

}

2567

}

2568

2569

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

2570

{

2571

char *interface = NULL;

2572

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

2573

interface))){

2574

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

2575

and if_nametoindex(interface) == 0){

2576

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

2577

fprintf_plus(stderr, "Not using nonexisting interface"

2578

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

2579

}

2580

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

2581

interface = NULL;

2582

}

1679

struct stat st;

1680

1681

/* Re-raise priviliges */

1682

errno = 0;

1683

ret = seteuid(0);

1684

if(ret == -1){

1685

perror_plus("seteuid");

1686

}

1687

1688

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

1689

int seckey_fd = open(seckey, O_RDONLY);

1690

if(seckey_fd == -1){

1691

perror_plus("open");

1692

} else {

1693

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

1694

if(ret == -1){

1695

perror_plus("fstat");

1696

} else {

1697

if(S_ISREG(st.st_mode)

1698

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

1699

ret = fchown(seckey_fd, uid, gid);

1700

if(ret == -1){

1701

perror_plus("fchown");

1702

}

1703

}

1704

}

1705

TEMP_FAILURE_RETRY(close(seckey_fd));

1706

}

1707

}

1708

1709

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

1710

int pubkey_fd = open(pubkey, O_RDONLY);

1711

if(pubkey_fd == -1){

1712

perror_plus("open");

1713

} else {

1714

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

1715

if(ret == -1){

1716

perror_plus("fstat");

1717

} else {

1718

if(S_ISREG(st.st_mode)

1719

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

1720

ret = fchown(pubkey_fd, uid, gid);

1721

if(ret == -1){

1722

perror_plus("fchown");

1723

}

1724

}

1725

}

1726

TEMP_FAILURE_RETRY(close(pubkey_fd));

1727

}

1728

}

1729

1730

/* Lower privileges */

1731

errno = 0;

1732

ret = seteuid(uid);

1733

if(ret == -1){

1734

perror_plus("seteuid");

2583

1735

}

2584

1736

}

2585

1737

2586

1738

/* Run network hooks */

2587

1739

{

2588

if(mc.interfaces != NULL){

2589

interfaces_hooks = malloc(mc.interfaces_size);

2590

if(interfaces_hooks == NULL){

2591

perror_plus("malloc");

2592

goto end;

2593

}

2594

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

2595

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

2596

}

2597

run_network_hooks("start", interfaces_hooks != NULL ?

2598

interfaces_hooks : "", delay);

1740

if(getuid() == 0){

1741

/* Re-raise priviliges */

1742

errno = 0;

1743

ret = seteuid(0);

1744

if(ret == -1){

1745

perror_plus("seteuid");

1746

}

1747

}

1748

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

1749

goto end;

1750

}

1751

if(getuid() == 0){

1752

/* Lower privileges */

1753

errno = 0;

1754

ret = seteuid(uid);

1755

if(ret == -1){

1756

perror_plus("seteuid");

1757

}

1758

}

2599

1759

}

2600

1760

2601

1761

if(not debug){

2602

1762

avahi_set_log_function(empty_log);

2603

1763

}

2604

1764

1765

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

1766

struct dirent **direntries;

1767

/* First look for interfaces that are up */

1768

ret = scandir(sys_class_net, &direntries, up_interface,

1769

alphasort);

1770

if(ret == 0){

1771

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

1772

free(direntries);

1773

ret = scandir(sys_class_net, &direntries, good_interface,

1774

alphasort);

1775

}

1776

if(ret >= 1){

1777

/* Pick the first interface returned */

1778

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

1779

if(debug){

1780

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

1781

}

1782

if(interface == NULL){

1783

perror_plus("malloc");

1784

free(direntries);

1785

exitcode = EXIT_FAILURE;

1786

goto end;

1787

}

1788

free(direntries);

1789

} else {

1790

free(direntries);

1791

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

1792

exitcode = EXIT_FAILURE;

1793

goto end;

1794

}

1795

}

1796

2605

1797

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

2606

1798

from the signal handler */

2607

1799

/* Initialize the pseudo-RNG for Avahi */

2608

1800

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

2609

simple_poll = avahi_simple_poll_new();

2610

if(simple_poll == NULL){

1801

mc.simple_poll = avahi_simple_poll_new();

1802

if(mc.simple_poll == NULL){

2611

1803

fprintf_plus(stderr,

2612

1804

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

2613

1805

exitcode = EX_UNAVAILABLE;

2677

1869

}

2678

1870

}

2679

1871

2680

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

2681

if(mc.interfaces == NULL){

2682

struct dirent **direntries = NULL;

2683

/* Look for any good interfaces */

2684

ret = scandir(sys_class_net, &direntries, good_interface,

2685

alphasort);

2686

if(ret >= 1){

2687

/* Add all found interfaces to interfaces list */

2688

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

2689

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

2690

direntries[i]->d_name);

2691

if(ret_errno != 0){

2692

errno = ret_errno;

2693

perror_plus("argz_add");

2694

free(direntries[i]);

2695

continue;

2696

}

2697

if(debug){

2698

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

2699

direntries[i]->d_name);

2700

}

2701

free(direntries[i]);

2702

}

2703

free(direntries);

2704

} else {

2705

if(ret == 0){

2706

free(direntries);

2707

}

2708

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

2709

exitcode = EXIT_FAILURE;

2710

goto end;

2711

}

2712

}

2713

2714

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

2715

{

2716

char *interface = NULL;

2717

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

2718

interface))){

2719

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

2720

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

2721

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

2722

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

2723

interface);

2724

interface = NULL;

2725

while((interface = argz_next(mc.interfaces,

2726

mc.interfaces_size, interface))){

2727

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

2728

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

2729

interface);

2730

interface = NULL;

1872

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

1873

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

1874

if_index = (AvahiIfIndex) if_nametoindex(interface);

1875

if(if_index == 0){

1876

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

1877

exitcode = EX_UNAVAILABLE;

1878

goto end;

1879

}

1880

1881

if(quit_now){

1882

goto end;

1883

}

1884

1885

/* Re-raise priviliges */

1886

errno = 0;

1887

ret = seteuid(0);

1888

if(ret == -1){

1889

perror_plus("seteuid");

1890

}

1891

1892

#ifdef __linux__

1893

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1894

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

1895

ret = klogctl(8, NULL, 5);

1896

bool restore_loglevel = true;

1897

if(ret == -1){

1898

restore_loglevel = false;

1899

perror_plus("klogctl");

1900

}

1901

#endif /* __linux__ */

1902

1903

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1904

if(sd < 0){

1905

perror_plus("socket");

1906

exitcode = EX_OSERR;

1907

#ifdef __linux__

1908

if(restore_loglevel){

1909

ret = klogctl(7, NULL, 0);

1910

if(ret == -1){

1911

perror_plus("klogctl");

1912

}

1913

}

1914

#endif /* __linux__ */

1915

/* Lower privileges */

1916

errno = 0;

1917

ret = seteuid(uid);

1918

if(ret == -1){

1919

perror_plus("seteuid");

1920

}

1921

goto end;

1922

}

1923

strcpy(network.ifr_name, interface);

1924

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

1925

if(ret == -1){

1926

perror_plus("ioctl SIOCGIFFLAGS");

1927

#ifdef __linux__

1928

if(restore_loglevel){

1929

ret = klogctl(7, NULL, 0);

1930

if(ret == -1){

1931

perror_plus("klogctl");

1932

}

1933

}

1934

#endif /* __linux__ */

1935

exitcode = EX_OSERR;

1936

/* Lower privileges */

1937

errno = 0;

1938

ret = seteuid(uid);

1939

if(ret == -1){

1940

perror_plus("seteuid");

1941

}

1942

goto end;

1943

}

1944

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

1945

network.ifr_flags |= IFF_UP;

1946

take_down_interface = true;

1947

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

1948

if(ret == -1){

1949

take_down_interface = false;

1950

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1951

exitcode = EX_OSERR;

1952

#ifdef __linux__

1953

if(restore_loglevel){

1954

ret = klogctl(7, NULL, 0);

1955

if(ret == -1){

1956

perror_plus("klogctl");

2731

1957

}

2732

1958

}

1959

#endif /* __linux__ */

1960

/* Lower privileges */

1961

errno = 0;

1962

ret = seteuid(uid);

1963

if(ret == -1){

1964

perror_plus("seteuid");

1965

}

1966

goto end;

1967

}

1968

}

1969

/* Sleep checking until interface is running.

1970

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

1971

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

1972

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

1973

if(ret == -1){

1974

perror_plus("ioctl SIOCGIFFLAGS");

1975

} else if(network.ifr_flags & IFF_RUNNING){

2733

1976

break;

2734

1977

}

2735

bool interface_was_up = interface_is_up(interface);

2736

errno = bring_up_interface(interface, delay);

2737

if(not interface_was_up){

2738

if(errno != 0){

2739

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

2740

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

2741

} else {

2742

errno = argz_add(&interfaces_to_take_down,

2743

&interfaces_to_take_down_size,

2744

interface);

2745

if(errno != 0){

2746

perror_plus("argz_add");

2747

}

2748

}

2749

}

2750

}

2751

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

2752

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

2753

}

2754

}

2755

2756

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

2757

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

2758

if(debug){

2759

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

2760

mc.interfaces);

2761

}

2762

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

1978

struct timespec sleeptime = { .tv_nsec = 250000000 };

1979

ret = nanosleep(&sleeptime, NULL);

1980

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

1981

perror_plus("nanosleep");

1982

}

1983

}

1984

if(not take_down_interface){

1985

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

1986

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

1987

if(ret == -1){

1988

perror_plus("close");

1989

}

1990

}

1991

#ifdef __linux__

1992

if(restore_loglevel){

1993

/* Restores kernel loglevel to default */

1994

ret = klogctl(7, NULL, 0);

1995

if(ret == -1){

1996

perror_plus("klogctl");

1997

}

1998

}

1999

#endif /* __linux__ */

2000

/* Lower privileges */

2001

errno = 0;

2002

/* Lower privileges */

2003

ret = seteuid(uid);

2004

if(ret == -1){

2005

perror_plus("seteuid");

2006

}

2763

2007

}

2764

2008

2765

2009

if(quit_now){

2766

2010

goto end;

2767

2011

}

2768

2012

2769

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

2013

ret = init_gnutls_global(pubkey, seckey);

2770

2014

if(ret == -1){

2771

2015

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

2772

2016

exitcode = EX_UNAVAILABLE;

2779

2023

goto end;

2780

2024

}

2781

2025

2782

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

2783

tempdir = mkdtemp(run_tempdir);

2784

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

2785

if(debug){

2786

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

2787

run_tempdir, old_tempdir);

2788

}

2789

tempdir = mkdtemp(old_tempdir);

2790

}

2791

if(tempdir == NULL){

2026

if(mkdtemp(tempdir) == NULL){

2792

2027

perror_plus("mkdtemp");

2793

2028

goto end;

2794

2029

}

2030

tempdir_created = true;

2795

2031

2796

2032

if(quit_now){

2797

2033

goto end;

2798

2034

}

2799

2035

2800

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

2036

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

2801

2037

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

2802

2038

exitcode = EX_UNAVAILABLE;

2803

2039

goto end;

2813

2049

/* Connect directly, do not use Zeroconf */

2814

2050

/* (Mainly meant for debugging) */

2815

2051

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

2816

2817

2052

if(address == NULL){

2818

2053

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

2819

2054

exitcode = EX_USAGE;

2824

2059

goto end;

2825

2060

}

2826

2061

2827

in_port_t port;

2062

uint16_t port;

2828

2063

errno = 0;

2829

2064

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

2830

2065

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

2831

or tmpmax != (in_port_t)tmpmax){

2066

or tmpmax != (uint16_t)tmpmax){

2832

2067

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

2833

2068

exitcode = EX_USAGE;

2834

2069

goto end;

2835

2070

}

2836

2071

2837

2072

if(quit_now){

2838

2073

goto end;

2839

2074

}

2840

2075

2841

port = (in_port_t)tmpmax;

2076

port = (uint16_t)tmpmax;

2842

2077

*address = '\0';

2843

2078

/* Colon in address indicates IPv6 */

2844

2079

int af;

2860

2095

}

2861

2096

2862

2097

while(not quit_now){

2863

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

2864

&mc);

2098

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

2865

2099

if(quit_now or ret == 0){

2866

2100

break;

2867

2101

}

2869

2103

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

2870

2104

(int)retry_interval);

2871

2105

}

2872

sleep((unsigned int)retry_interval);

2106

sleep((int)retry_interval);

2873

2107

}

2874

2108

2875

if(not quit_now){

2109

if (not quit_now){

2876

2110

exitcode = EXIT_SUCCESS;

2877

2111

}

2878

2112

2893

2127

config.publish_domain = 0;

2894

2128

2895

2129

/* Allocate a new server */

2896

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2897

&config, NULL, NULL, &ret_errno);

2130

mc.server = avahi_server_new(avahi_simple_poll_get

2131

(mc.simple_poll), &config, NULL,

2132

NULL, &error);

2898

2133

2899

2134

/* Free the Avahi configuration data */

2900

2135

avahi_server_config_free(&config);

2903

2138

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

2904

2139

if(mc.server == NULL){

2905

2140

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

2906

avahi_strerror(ret_errno));

2141

avahi_strerror(error));

2907

2142

exitcode = EX_UNAVAILABLE;

2908

2143

goto end;

2909

2144

}

2915

2150

/* Create the Avahi service browser */

2916

2151

sb = avahi_s_service_browser_new(mc.server, if_index,

2917

2152

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2918

NULL, 0, browse_callback,

2919

(void *)&mc);

2153

NULL, 0, browse_callback, NULL);

2920

2154

if(sb == NULL){

2921

2155

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

2922

2156

avahi_strerror(avahi_server_errno(mc.server)));

2933

2167

if(debug){

2934

2168

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

2935

2169

}

2936

2937

ret = avahi_loop_with_timeout(simple_poll,

2938

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

2170

2171

ret = avahi_loop_with_timeout(mc.simple_poll,

2172

(int)(retry_interval * 1000));

2939

2173

if(debug){

2940

2174

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

2941

2175

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

2948

2182

}

2949

2183

2950

2184

/* Cleanup things */

2951

free(mc.interfaces);

2952

2953

2185

if(sb != NULL)

2954

2186

avahi_s_service_browser_free(sb);

2955

2187

2956

2188

if(mc.server != NULL)

2957

2189

avahi_server_free(mc.server);

2958

2190

2959

if(simple_poll != NULL)

2960

avahi_simple_poll_free(simple_poll);

2191

if(mc.simple_poll != NULL)

2192

avahi_simple_poll_free(mc.simple_poll);

2961

2193

2962

2194

if(gnutls_initialized){

2963

2195

gnutls_certificate_free_credentials(mc.cred);

2196

gnutls_global_deinit();

2964

2197

gnutls_dh_params_deinit(mc.dh_params);

2965

2198

}

2966

2199

2967

2200

if(gpgme_initialized){

2968

2201

gpgme_release(mc.ctx);

2969

2202

}

2970

2203

2971

2204

/* Cleans up the circular linked list of Mandos servers the client

2972

2205

has seen */

2973

2206

if(mc.current_server != NULL){

2974

2207

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

2975

2208

while(mc.current_server != NULL){

2976

2209

server *next = mc.current_server->next;

2977

#ifdef __GNUC__

2978

#pragma GCC diagnostic push

2979

#pragma GCC diagnostic ignored "-Wcast-qual"

2980

#endif

2981

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

2982

#ifdef __GNUC__

2983

#pragma GCC diagnostic pop

2984

#endif

2985

2210

free(mc.current_server);

2986

2211

mc.current_server = next;

2987

2212

}

2988

2213

}

2989

2214

2990

/* Re-raise privileges */

2215

/* Re-raise priviliges */

2991

2216

{

2992

ret_errno = raise_privileges();

2993

if(ret_errno != 0){

2994

errno = ret_errno;

2995

perror_plus("Failed to raise privileges");

2996

} else {

2997

2998

/* Run network hooks */

2999

run_network_hooks("stop", interfaces_hooks != NULL ?

3000

interfaces_hooks : "", delay);

3001

3002

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

3003

{

3004

char *interface = NULL;

3005

while((interface=argz_next(interfaces_to_take_down,

3006

interfaces_to_take_down_size,

3007

interface))){

3008

ret_errno = take_down_interface(interface);

3009

if(ret_errno != 0){

3010

errno = ret_errno;

3011

perror_plus("Failed to take down interface");

3012

}

3013

}

3014

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

3015

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

3016

" down\n");

3017

}

2217

if(getuid() == 0){

2218

errno = 0;

2219

ret = seteuid(0);

2220

if(ret == -1){

2221

perror_plus("seteuid");

3018

2222

}

3019

2223

}

2224

/* Run network hooks */

2225

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

2226

goto end;

2227

}

3020

2228

3021

ret_errno = lower_privileges_permanently();

3022

if(ret_errno != 0){

3023

errno = ret_errno;

3024

perror_plus("Failed to lower privileges permanently");

3025

}

3026

}

3027

3028

free(interfaces_to_take_down);

3029

free(interfaces_hooks);

3030

3031

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

3032

uintmax_t level){

2229

/* Take down the network interface */

2230

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

2231

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

2232

if(ret == -1){

2233

perror_plus("ioctl SIOCGIFFLAGS");

2234

} else if(network.ifr_flags & IFF_UP){

2235

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

2236

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

2237

if(ret == -1){

2238

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2239

}

2240

}

2241

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

2242

if(ret == -1){

2243

perror_plus("close");

2244

}

2245

}

2246

}

2247

if(getuid() == 0){

2248

/* Lower privileges permanently */

2249

errno = 0;

2250

ret = setuid(uid);

2251

if(ret == -1){

2252

perror_plus("setuid");

2253

}

2254

}

2255

2256

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

2257

if(tempdir_created){

3033

2258

struct dirent **direntries = NULL;

3034

int dret;

3035

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

3036

O_RDONLY

3037

| O_NOFOLLOW

3038

| O_DIRECTORY

3039

| O_PATH));

3040

if(dir_fd == -1){

3041

perror_plus("open");

3042

}

3043

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

3044

notdotentries, alphasort);

3045

if(numentries >= 0){

2259

struct dirent *direntry = NULL;

2260

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

2261

alphasort);

2262

if (numentries > 0){

3046

2263

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

3047

if(debug){

3048

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

3049

dirname, direntries[i]->d_name);

3050

}

3051

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

3052

if(dret == -1){

3053

if(errno == EISDIR){

3054

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

3055

AT_REMOVEDIR);

3056

}

3057

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

3058

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

3059

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

3060

/* Recurse only in this special case */

3061

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

3062

dret = 0;

3063

}

3064

if(dret == -1){

3065

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

3066

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

3067

}

3068

}

3069

free(direntries[i]);

3070

}

3071

3072

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

3073

free(direntries);

3074

if(numentries == -1){

3075

perror_plus("scandirat");

3076

}

3077

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3078

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

3079

perror_plus("rmdir");

3080

}

3081

} else {

3082

perror_plus("scandirat");

3083

}

3084

close(dir_fd);

3085

}

3086

3087

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

3088

if(tempdir != NULL){

3089

clean_dir_at(-1, tempdir, 0);

2264

direntry = direntries[i];

2265

char *fullname = NULL;

2266

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

2267

direntry->d_name);

2268

if(ret < 0){

2269

perror_plus("asprintf");

2270

continue;

2271

}

2272

ret = remove(fullname);

2273

if(ret == -1){

2274

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

2275

strerror(errno));

2276

}

2277

free(fullname);

2278

}

2279

}

2280

2281

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

2282

free(direntries);

2283

if (numentries == -1){

2284

perror_plus("scandir");

2285

}

2286

ret = rmdir(tempdir);

2287

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

2288

perror_plus("rmdir");

2289

}

3090

2290

}

3091

2291

3092

2292

if(quit_now){