/mandos/trunk : revision 831

9

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

10

*

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* Everything else is

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13

12

13

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*

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* This program is free software: you can redistribute it and/or

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

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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40

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

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

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stdout, ferror(), remove() */

44

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

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stdout, ferror() */

44

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

45

#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> /* memset(), strcmp(), strlen(),

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

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

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asprintf(), strncpy() */

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

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

60

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

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62

*/

62

63

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

63

64

strtoimax() */

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

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

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

66

70

program_invocation_short_name */

67

71

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

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72

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

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77

*/

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78

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

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79

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

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setgid(), pause() */

77

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

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

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unlinkat() */

82

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

78

83

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

79

84

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

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85

argp_state, struct argp,

87

92

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

93

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

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94

WEXITSTATUS(), WTERMSIG() */

95

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

100

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

101

EAI_SYSTEM, gai_strerror() */

90

102

91

103

#ifdef __linux__

92

104

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

134

146

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

135

147

char *connect_to = NULL;

136

148

const char *hookdir = HOOKDIR;

149

int hookdir_fd = -1;

150

uid_t uid = 65534;

151

gid_t gid = 65534;

137

152

138

153

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

139

154

typedef struct server{

140

155

const char *ip;

141

uint16_t port;

156

in_port_t port;

142

157

AvahiIfIndex if_index;

143

158

int af;

144

159

struct timespec last_seen;

148

163

149

164

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

150

165

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

166

AvahiServer *server;

153

167

gnutls_certificate_credentials_t cred;

154

168

unsigned int dh_bits;

156

170

const char *priority;

157

171

gpgme_ctx_t ctx;

158

172

server *current_server;

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char *interfaces;

174

size_t interfaces_size;

159

175

} mandos_context;

160

176

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

177

/* global so signal handler can reach it*/

178

AvahiSimplePoll *simple_poll;

166

179

167

180

sig_atomic_t quit_now = 0;

168

181

int signal_received = 0;

169

182

170

183

/* Function to use when printing errors */

171

184

void perror_plus(const char *print_text){

185

int e = errno;

172

186

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

173

187

program_invocation_short_name);

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errno = e;

174

189

perror(print_text);

175

190

}

176

191

192

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

177

193

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

178

194

va_list ap;

179

195

va_start (ap, format);

180

196

181

197

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

182

198

program_invocation_short_name));

183

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

199

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

184

200

}

185

201

186

202

/*

188

204

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

189

205

* "buffer_length" is how much is already used.

190

206

*/

207

__attribute__((nonnull, warn_unused_result))

191

208

size_t incbuffer(char **buffer, size_t buffer_length,

192

209

size_t buffer_capacity){

193

210

if(buffer_length + BUFFER_SIZE > buffer_capacity){

194

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

195

if(buffer == NULL){

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;

196

217

return 0;

197

218

}

219

*buffer = new_buf;

198

220

buffer_capacity += BUFFER_SIZE;

199

221

}

200

222

return buffer_capacity;

201

223

}

202

224

203

225

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

204

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

205

int af){

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){

206

229

int ret;

207

230

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

208

231

if(new_server == NULL){

209

232

perror_plus("malloc");

210

return -1;

233

return false;

211

234

}

212

235

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

213

236

.port = port,

215

238

.af = af };

216

239

if(new_server->ip == NULL){

217

240

perror_plus("strdup");

218

return -1;

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;

219

257

}

220

258

/* Special case of first server */

221

if (mc.current_server == NULL){

259

if(*current_server == NULL){

222

260

new_server->next = new_server;

223

261

new_server->prev = new_server;

224

mc.current_server = new_server;

225

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

262

*current_server = new_server;

226

263

} else {

227

new_server->next = mc.current_server;

228

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

264

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

265

new_server->next = *current_server;

266

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

229

267

new_server->prev->next = new_server;

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;

268

(*current_server)->prev = new_server;

269

}

270

return true;

238

271

}

239

272

240

273

/*

241

274

* Initialize GPGME.

242

275

*/

243

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

244

const char *tempdir){

276

__attribute__((nonnull, warn_unused_result))

277

static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

279

const char * const tempdir,

280

mandos_context *mc){

245

281

gpgme_error_t rc;

246

282

gpgme_engine_info_t engine_info;

247

283

248

249

284

/*

250

285

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

251

286

*/

252

bool import_key(const char *filename){

287

bool import_key(const char * const filename){

253

288

int ret;

254

289

int fd;

255

290

gpgme_data_t pgp_data;

267

302

return false;

268

303

}

269

304

270

rc = gpgme_op_import(mc.ctx, pgp_data);

305

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

271

306

if(rc != GPG_ERR_NO_ERROR){

272

307

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

273

308

gpgme_strsource(rc), gpgme_strerror(rc));

274

309

return false;

275

310

}

276

311

277

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

312

ret = close(fd);

278

313

if(ret == -1){

279

314

perror_plus("close");

280

315

}

317

352

}

318

353

319

354

/* Create new GPGME "context" */

320

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

355

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

321

356

if(rc != GPG_ERR_NO_ERROR){

322

357

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

323

358

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

336

371

* Decrypt OpenPGP data.

337

372

* Returns -1 on error

338

373

*/

374

__attribute__((nonnull, warn_unused_result))

339

375

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

376

size_t crypto_size,

341

char **plaintext){

377

char **plaintext,

378

mandos_context *mc){

342

379

gpgme_data_t dh_crypto, dh_plain;

343

380

gpgme_error_t rc;

344

381

ssize_t ret;

370

407

371

408

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

372

409

data buffer */

373

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

410

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

374

411

if(rc != GPG_ERR_NO_ERROR){

375

412

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

376

413

gpgme_strsource(rc), gpgme_strerror(rc));

377

414

plaintext_length = -1;

378

415

if(debug){

379

416

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

417

result = gpgme_op_decrypt_result(mc->ctx);

381

418

if(result == NULL){

382

419

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

383

420

} else {

460

497

return plaintext_length;

461

498

}

462

499

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;

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);

469

511

}

470

512

471

513

/* GnuTLS log function callback */

514

__attribute__((nonnull))

472

515

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

473

516

const char* string){

474

517

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

475

518

}

476

519

520

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

477

521

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

522

const char *seckeyfilename,

523

const char *dhparamsfilename,

524

mandos_context *mc){

479

525

int ret;

526

unsigned int uret;

480

527

481

528

if(debug){

482

529

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

483

530

}

484

531

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

492

532

if(debug){

493

533

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

494

534

* - GnuTLS manual

498

538

}

499

539

500

540

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

541

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

542

if(ret != GNUTLS_E_SUCCESS){

503

543

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

504

544

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

506

545

return -1;

507

546

}

508

547

514

553

}

515

554

516

555

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

556

(mc->cred, pubkeyfilename, seckeyfilename,

518

557

GNUTLS_OPENPGP_FMT_BASE64);

519

558

if(ret != GNUTLS_E_SUCCESS){

520

559

fprintf_plus(stderr,

526

565

}

527

566

528

567

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

568

ret = gnutls_dh_params_init(&mc->dh_params);

530

569

if(ret != GNUTLS_E_SUCCESS){

531

570

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

571

" initialization: %s\n",

533

572

safer_gnutls_strerror(ret));

534

573

goto globalfail;

535

574

}

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);

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);

544

748

545

749

return 0;

546

750

547

751

globalfail:

548

752

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

753

gnutls_certificate_free_credentials(mc->cred);

754

gnutls_dh_params_deinit(mc->dh_params);

552

755

return -1;

553

756

}

554

757

555

static int init_gnutls_session(gnutls_session_t *session){

758

__attribute__((nonnull, warn_unused_result))

759

static int init_gnutls_session(gnutls_session_t *session,

760

mandos_context *mc){

556

761

int ret;

557

762

/* GnuTLS session creation */

558

763

do {

570

775

{

571

776

const char *err;

572

777

do {

573

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

778

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

574

779

if(quit_now){

575

780

gnutls_deinit(*session);

576

781

return -1;

587

792

588

793

do {

589

794

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

795

mc->cred);

591

796

if(quit_now){

592

797

gnutls_deinit(*session);

593

798

return -1;

603

808

/* ignore client certificate if any. */

604

809

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

810

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

811

return 0;

609

812

}

610

813

612

815

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

613

816

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

614

817

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

615

1036

/* Called when a Mandos server is found */

616

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

1037

__attribute__((nonnull, warn_unused_result))

1038

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

617

1039

AvahiIfIndex if_index,

618

int af){

1040

int af, mandos_context *mc){

619

1041

int ret, tcp_sd = -1;

620

1042

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1043

struct sockaddr_storage to;

625

1044

char *buffer = NULL;

626

1045

char *decrypted_buffer = NULL;

627

1046

size_t buffer_length = 0;

630

1049

int retval = -1;

631

1050

gnutls_session_t session;

632

1051

int pf; /* Protocol family */

1052

bool route_added = false;

633

1053

634

1054

errno = 0;

635

1055

651

1071

return -1;

652

1072

}

653

1073

654

ret = init_gnutls_session(&session);

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);

655

1107

if(ret != 0){

656

1108

return -1;

657

1109

}

658

1110

659

1111

if(debug){

660

1112

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

661

PRIu16 "\n", ip, port);

1113

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

662

1114

}

663

1115

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1116

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

665

1117

if(tcp_sd < 0){

666

1118

int e = errno;

667

1119

perror_plus("socket");

674

1126

goto mandos_end;

675

1127

}

676

1128

677

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

678

1129

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

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);

681

1133

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

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);

684

1137

}

685

1138

if(ret < 0 ){

686

1139

int e = errno;

695

1148

goto mandos_end;

696

1149

}

697

1150

if(af == AF_INET6){

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*/

1151

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

1152

if(IN6_IS_ADDR_LINKLOCAL

1153

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

705

1154

if(if_index == AVAHI_IF_UNSPEC){

706

1155

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

707

1156

" incomplete without a network interface\n");

709

1158

goto mandos_end;

710

1159

}

711

1160

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1161

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

713

1162

}

714

1163

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1164

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

718

1165

}

719

1166

720

1167

if(quit_now){

728

1175

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

729

1176

perror_plus("if_indextoname");

730

1177

} else {

731

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

732

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

1178

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

1179

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

733

1180

}

734

1181

} else {

735

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

736

ip, port);

1182

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

1183

ip, (uintmax_t)port);

737

1184

}

738

1185

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1186

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

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;

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;

779

1267

}

780

1268

781

1269

const char *out = mandos_protocol_version;

817

1305

goto mandos_end;

818

1306

}

819

1307

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

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);

822

1313

823

1314

if(quit_now){

824

1315

errno = EINTR;

929

1420

if(buffer_length > 0){

930

1421

ssize_t decrypted_buffer_size;

931

1422

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1423

&decrypted_buffer, mc);

933

1424

if(decrypted_buffer_size >= 0){

934

1425

935

1426

written = 0;

961

1452

962

1453

mandos_end:

963

1454

{

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

}

964

1461

int e = errno;

965

1462

free(decrypted_buffer);

966

1463

free(buffer);

967

1464

if(tcp_sd >= 0){

968

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

1465

ret = close(tcp_sd);

969

1466

}

970

1467

if(ret == -1){

971

1468

if(e == 0){

983

1480

return retval;

984

1481

}

985

1482

1483

__attribute__((nonnull))

986

1484

static void resolve_callback(AvahiSServiceResolver *r,

987

1485

AvahiIfIndex interface,

988

1486

AvahiProtocol proto,

996

1494

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1495

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1496

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1497

void *mc){

1498

if(r == NULL){

1499

return;

1500

}

1001

1501

1002

1502

/* Called whenever a service has been resolved successfully or

1003

1503

timed out */

1004

1504

1005

1505

if(quit_now){

1506

avahi_s_service_resolver_free(r);

1006

1507

return;

1007

1508

}

1008

1509

1012

1513

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

1013

1514

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

1014

1515

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1516

avahi_strerror(avahi_server_errno

1517

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

1016

1518

break;

1017

1519

1018

1520

case AVAHI_RESOLVER_FOUND:

1024

1526

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

1025

1527

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

1026

1528

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1529

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

1530

interface,

1531

avahi_proto_to_af(proto),

1532

mc);

1029

1533

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1534

avahi_simple_poll_quit(simple_poll);

1031

1535

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

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

}

1034

1542

}

1035

1543

}

1036

1544

}

1046

1554

const char *domain,

1047

1555

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1556

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1557

void *mc){

1558

if(b == NULL){

1559

return;

1560

}

1051

1561

1052

1562

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

1053

1563

is removed from the LAN */

1061

1571

case AVAHI_BROWSER_FAILURE:

1062

1572

1063

1573

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1574

avahi_strerror(avahi_server_errno

1575

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

1576

avahi_simple_poll_quit(simple_poll);

1066

1577

return;

1067

1578

1068

1579

case AVAHI_BROWSER_NEW:

1071

1582

the callback function is called the Avahi server will free the

1072

1583

resolver for us. */

1073

1584

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

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)

1077

1589

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

1078

1590

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1591

avahi_strerror(avahi_server_errno

1592

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

1080

1593

break;

1081

1594

1082

1595

case AVAHI_BROWSER_REMOVE:

1101

1614

signal_received = sig;

1102

1615

int old_errno = errno;

1103

1616

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1617

if(simple_poll != NULL){

1618

avahi_simple_poll_quit(simple_poll);

1106

1619

}

1107

1620

errno = old_errno;

1108

1621

}

1109

1622

1623

__attribute__((nonnull, warn_unused_result))

1110

1624

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

1111

1625

int ret;

1626

int old_errno;

1112

1627

1113

1628

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

1114

1629

if(s < 0){

1630

old_errno = errno;

1115

1631

perror_plus("socket");

1632

errno = old_errno;

1116

1633

return false;

1117

1634

}

1118

strcpy(ifr->ifr_name, ifname);

1635

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

1636

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

1119

1637

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1638

if(ret == -1){

1121

1639

if(debug){

1640

old_errno = errno;

1122

1641

perror_plus("ioctl SIOCGIFFLAGS");

1642

errno = old_errno;

1123

1643

}

1124

1644

return false;

1125

1645

}

1126

1646

return true;

1127

1647

}

1128

1648

1649

__attribute__((nonnull, warn_unused_result))

1129

1650

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

1130

1651

1131

1652

/* Reject the loopback device */

1173

1694

* corresponds to an acceptable network device.

1174

1695

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

1175

1696

*/

1697

__attribute__((nonnull, warn_unused_result))

1176

1698

int good_interface(const struct dirent *if_entry){

1177

1699

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

1178

1700

return 0;

1194

1716

}

1195

1717

1196

1718

/*

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

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))

1239

1753

int notdotentries(const struct dirent *direntry){

1240

1754

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

1241

1755

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

1248

1762

}

1249

1763

1250

1764

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

1765

__attribute__((nonnull, warn_unused_result))

1251

1766

int runnable_hook(const struct dirent *direntry){

1252

1767

int ret;

1253

1768

size_t sret;

1261

1776

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

1262

1777

"abcdefghijklmnopqrstuvwxyz"

1263

1778

"0123456789"

1264

"_-");

1779

"_.-");

1265

1780

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

1266

1781

/* Contains non-allowed characters */

1267

1782

if(debug){

1271

1786

return 0;

1272

1787

}

1273

1788

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);

1789

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

1282

1790

if(ret == -1){

1283

1791

if(debug){

1284

1792

perror_plus("Could not stat hook");

1301

1809

}

1302

1810

return 0;

1303

1811

}

1812

if(debug){

1813

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

1814

direntry->d_name);

1815

}

1304

1816

return 1;

1305

1817

}

1306

1818

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1819

__attribute__((nonnull, warn_unused_result))

1820

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1821

mandos_context *mc){

1308

1822

int ret;

1309

1823

struct timespec now;

1310

1824

struct timespec waited_time;

1311

1825

intmax_t block_time;

1312

1826

1313

1827

while(true){

1314

if(mc.current_server == NULL){

1315

if (debug){

1828

if(mc->current_server == NULL){

1829

if(debug){

1316

1830

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

1317

1831

" No timeout!\n");

1318

1832

}

1319

1833

ret = avahi_simple_poll_iterate(s, -1);

1320

1834

} else {

1321

if (debug){

1835

if(debug){

1322

1836

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

1323

1837

" it, or wait\n");

1324

1838

}

1331

1845

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

1332

1846

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

1333

1847

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

1848

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

1335

1849

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

1850

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

1337

1851

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

1338

1852

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

1339

1853

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

1341

1855

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

1342

1856

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

1343

1857

1344

if (debug){

1858

if(debug){

1345

1859

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

1346

1860

block_time);

1347

1861

}

1348

1862

1349

1863

if(block_time <= 0){

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);

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);

1354

1868

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

1869

avahi_simple_poll_quit(s);

1356

1870

return 0;

1357

1871

}

1358

1872

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

1873

&mc->current_server->last_seen);

1360

1874

if(ret == -1){

1361

1875

perror_plus("clock_gettime");

1362

1876

return -1;

1363

1877

}

1364

mc.current_server = mc.current_server->next;

1878

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

1365

1879

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

1366

1880

servers, but don't block */

1367

1881

}

1369

1883

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

1370

1884

}

1371

1885

if(ret != 0){

1372

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

1886

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

1373

1887

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

1374

1888

}

1375

1889

}

1376

1890

}

1377

1891

}

1378

1892

1379

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

1893

__attribute__((nonnull))

1894

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

1380

1895

const float delay){

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

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

1385

alphasort);

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);

1386

1914

if(numhooks == -1){

1387

1915

perror_plus("scandir");

1388

} else {

1389

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

1390

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

1391

direntry = direntries[0];

1392

char *fullname = NULL;

1393

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

1394

if(ret < 0){

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){

1395

1977

perror_plus("asprintf");

1396

continue;

1978

_exit(EX_OSERR);

1397

1979

}

1398

pid_t hook_pid = fork();

1399

if(hook_pid == 0){

1400

/* Child */

1401

dup2(devnull, STDIN_FILENO);

1402

close(devnull);

1403

dup2(STDERR_FILENO, STDOUT_FILENO);

1404

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

1405

if(ret == -1){

1406

perror_plus("setenv");

1407

return false;

1408

}

1409

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

1410

if(ret == -1){

1411

perror_plus("setenv");

1412

return false;

1413

}

1414

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

1415

if(ret == -1){

1416

perror_plus("setenv");

1417

return false;

1418

}

1419

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

1420

if(ret == -1){

1421

perror_plus("setenv");

1422

return false;

1423

}

1424

char *delaystring;

1425

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

1426

if(ret == -1){

1427

perror_plus("asprintf");

1428

return false;

1429

}

1430

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

1431

if(ret == -1){

1432

free(delaystring);

1433

perror_plus("setenv");

1434

return false;

1435

}

1980

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

1981

if(ret == -1){

1436

1982

free(delaystring);

1437

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

1438

perror_plus("execl");

1439

} else {

1440

int status;

1441

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

1442

perror_plus("waitpid");

1443

free(fullname);

1444

continue;

1445

}

1446

if(WIFEXITED(status)){

1447

if(WEXITSTATUS(status) != 0){

1448

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

1449

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

1450

WEXITSTATUS(status));

1451

free(fullname);

1452

continue;

1453

}

1454

} else if(WIFSIGNALED(status)){

1455

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

1456

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

1457

WTERMSIG(status));

1458

free(fullname);

1459

continue;

1460

} else {

1461

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

1462

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

1463

free(fullname);

1464

continue;

1465

}

1466

}

1467

free(fullname);

1468

if(quit_now){

1469

break;

1470

}

1471

}

1472

close(devnull);

1473

}

1474

return true;

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

int bring_up_interface(const char *const interface,

2075

const float delay){

2076

int 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

int ret_errno = 0;

2093

int ioctl_errno = 0;

2094

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

2095

ret_errno = errno;

2096

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

2097

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

2098

errno = old_errno;

2099

return ret_errno;

2100

}

2101

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

2102

2103

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

2104

if(sd == -1){

2105

ret_errno = errno;

2106

perror_plus("socket");

2107

errno = old_errno;

2108

return ret_errno;

2109

}

2110

2111

if(quit_now){

2112

ret = close(sd);

2113

if(ret == -1){

2114

perror_plus("close");

2115

}

2116

errno = old_errno;

2117

return EINTR;

2118

}

2119

2120

if(debug){

2121

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

2122

interface);

2123

}

2124

2125

/* Raise privileges */

2126

ret_errno = raise_privileges();

2127

if(ret_errno != 0){

2128

errno = ret_errno;

2129

perror_plus("Failed to raise privileges");

2130

}

2131

2132

#ifdef __linux__

2133

int ret_linux;

2134

bool restore_loglevel = false;

2135

if(ret_errno == 0){

2136

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2137

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

2138

ret_linux = klogctl(8, NULL, 5);

2139

if(ret_linux == -1){

2140

perror_plus("klogctl");

2141

} else {

2142

restore_loglevel = true;

2143

}

2144

}

2145

#endif /* __linux__ */

2146

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

2147

ioctl_errno = errno;

2148

#ifdef __linux__

2149

if(restore_loglevel){

2150

ret_linux = klogctl(7, NULL, 0);

2151

if(ret_linux == -1){

2152

perror_plus("klogctl");

2153

}

2154

}

2155

#endif /* __linux__ */

2156

2157

/* If raise_privileges() succeeded above */

2158

if(ret_errno == 0){

2159

/* Lower privileges */

2160

ret_errno = lower_privileges();

2161

if(ret_errno != 0){

2162

errno = ret_errno;

2163

perror_plus("Failed to lower privileges");

2164

}

2165

}

2166

2167

/* Close the socket */

2168

ret = close(sd);

2169

if(ret == -1){

2170

perror_plus("close");

2171

}

2172

2173

if(ret_setflags == -1){

2174

errno = ioctl_errno;

2175

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2176

errno = old_errno;

2177

return ioctl_errno;

2178

}

2179

} else if(debug){

2180

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

2181

interface);

2182

}

2183

2184

/* Sleep checking until interface is running.

2185

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

2186

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

2187

if(interface_is_running(interface)){

2188

break;

2189

}

2190

struct timespec sleeptime = { .tv_nsec = 250000000 };

2191

ret = nanosleep(&sleeptime, NULL);

2192

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

2193

perror_plus("nanosleep");

2194

}

2195

}

2196

2197

errno = old_errno;

2198

return 0;

2199

}

2200

2201

__attribute__((nonnull, warn_unused_result))

2202

int take_down_interface(const char *const interface){

2203

int old_errno = errno;

2204

struct ifreq network;

2205

unsigned int if_index = if_nametoindex(interface);

2206

if(if_index == 0){

2207

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

2208

errno = old_errno;

2209

return ENXIO;

2210

}

2211

if(interface_is_up(interface)){

2212

int ret_errno = 0;

2213

int ioctl_errno = 0;

2214

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

2215

ret_errno = errno;

2216

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

2217

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

2218

errno = old_errno;

2219

return ret_errno;

2220

}

2221

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

2222

2223

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

2224

if(sd == -1){

2225

ret_errno = errno;

2226

perror_plus("socket");

2227

errno = old_errno;

2228

return ret_errno;

2229

}

2230

2231

if(debug){

2232

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

2233

interface);

2234

}

2235

2236

/* Raise privileges */

2237

ret_errno = raise_privileges();

2238

if(ret_errno != 0){

2239

errno = ret_errno;

2240

perror_plus("Failed to raise privileges");

2241

}

2242

2243

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

2244

ioctl_errno = errno;

2245

2246

/* If raise_privileges() succeeded above */

2247

if(ret_errno == 0){

2248

/* Lower privileges */

2249

ret_errno = lower_privileges();

2250

if(ret_errno != 0){

2251

errno = ret_errno;

2252

perror_plus("Failed to lower privileges");

2253

}

2254

}

2255

2256

/* Close the socket */

2257

int ret = close(sd);

2258

if(ret == -1){

2259

perror_plus("close");

2260

}

2261

2262

if(ret_setflags == -1){

2263

errno = ioctl_errno;

2264

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2265

errno = old_errno;

2266

return ioctl_errno;

2267

}

2268

} else if(debug){

2269

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

2270

interface);

2271

}

2272

2273

errno = old_errno;

2274

return 0;

1475

2275

}

1476

2276

1477

2277

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

2278

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

2279

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

2280

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

2281

.current_server = NULL, .interfaces = NULL,

2282

.interfaces_size = 0 };

1478

2283

AvahiSServiceBrowser *sb = NULL;

1479

int error;

2284

error_t ret_errno;

1480

2285

int ret;

1481

2286

intmax_t tmpmax;

1482

2287

char *tmp;

1483

2288

int exitcode = EXIT_SUCCESS;

1484

const char *interface = "";

1485

struct ifreq network;

1486

int sd = -1;

1487

bool take_down_interface = false;

1488

uid_t uid;

1489

gid_t gid;

1490

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

1491

bool tempdir_created = false;

2289

char *interfaces_to_take_down = NULL;

2290

size_t interfaces_to_take_down_size = 0;

2291

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

2292

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

2293

char *tempdir = NULL;

1492

2294

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1493

2295

const char *seckey = PATHDIR "/" SECKEY;

1494

2296

const char *pubkey = PATHDIR "/" PUBKEY;

2297

const char *dh_params_file = NULL;

2298

char *interfaces_hooks = NULL;

1495

2299

1496

2300

bool gnutls_initialized = false;

1497

2301

bool gpgme_initialized = false;

1549

2353

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

1550

2354

" Diffie-Hellman key exchange",

1551

2355

.group = 2 },

2356

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

2357

.arg = "FILE",

2358

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

2359

" for the Diffie-Hellman key exchange",

2360

.group = 2 },

1552

2361

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

1553

2362

.arg = "STRING",

1554

2363

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

1559

2368

.group = 2 },

1560

2369

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

1561

2370

.arg = "SECONDS",

1562

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

2371

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

1563

2372

.group = 2 },

1564

2373

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

1565

2374

.arg = "DIR",

1588

2397

connect_to = arg;

1589

2398

break;

1590

2399

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

1591

interface = arg;

2400

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

2401

arg, (int)',');

2402

if(ret_errno != 0){

2403

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

2404

}

1592

2405

break;

1593

2406

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

1594

2407

seckey = arg;

1605

2418

}

1606

2419

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

1607

2420

break;

2421

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

2422

dh_params_file = arg;

2423

break;

1608

2424

case 130: /* --priority */

1609

2425

mc.priority = arg;

1610

2426

break;

1637

2453

argp_state_help(state, state->out_stream,

1638

2454

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1639

2455

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

1640

fprintf_plus(state->out_stream,

1641

"Mandos plugin mandos-client: ");

1642

2456

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

1643

2457

exit(argp_err_exit_status);

1644

2458

break;

1652

2466

.args_doc = "",

1653

2467

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

1654

2468

" passwords from a Mandos server" };

1655

ret = argp_parse(&argp, argc, argv,

1656

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1657

switch(ret){

2469

ret_errno = argp_parse(&argp, argc, argv,

2470

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2471

switch(ret_errno){

1658

2472

case 0:

1659

2473

break;

1660

2474

case ENOMEM:

1661

2475

default:

1662

errno = ret;

2476

errno = ret_errno;

1663

2477

perror_plus("argp_parse");

1664

2478

exitcode = EX_OSERR;

1665

2479

goto end;

1668

2482

goto end;

1669

2483

}

1670

2484

}

1671

2485

1672

2486

{

1673

2487

/* Work around Debian bug #633582:

1674

2488

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

1675

struct stat st;

1676

1677

/* Re-raise priviliges */

1678

errno = 0;

1679

ret = seteuid(0);

1680

if(ret == -1){

1681

perror_plus("seteuid");

1682

}

1683

1684

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

1685

int seckey_fd = open(seckey, O_RDONLY);

1686

if(seckey_fd == -1){

1687

perror_plus("open");

1688

} else {

1689

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

1690

if(ret == -1){

1691

perror_plus("fstat");

1692

} else {

1693

if(S_ISREG(st.st_mode)

1694

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

1695

ret = fchown(seckey_fd, uid, gid);

1696

if(ret == -1){

1697

perror_plus("fchown");

1698

}

1699

}

1700

}

1701

TEMP_FAILURE_RETRY(close(seckey_fd));

1702

}

1703

}

1704

1705

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

1706

int pubkey_fd = open(pubkey, O_RDONLY);

1707

if(pubkey_fd == -1){

1708

perror_plus("open");

1709

} else {

1710

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

1711

if(ret == -1){

1712

perror_plus("fstat");

1713

} else {

1714

if(S_ISREG(st.st_mode)

1715

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

1716

ret = fchown(pubkey_fd, uid, gid);

1717

if(ret == -1){

1718

perror_plus("fchown");

1719

}

1720

}

1721

}

1722

TEMP_FAILURE_RETRY(close(pubkey_fd));

1723

}

1724

}

1725

1726

/* Lower privileges */

1727

errno = 0;

1728

ret = seteuid(uid);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2489

2490

/* Re-raise privileges */

2491

ret = raise_privileges();

2492

if(ret != 0){

2493

errno = ret;

2494

perror_plus("Failed to raise privileges");

2495

} else {

2496

struct stat st;

2497

2498

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

2499

int seckey_fd = open(seckey, O_RDONLY);

2500

if(seckey_fd == -1){

2501

perror_plus("open");

2502

} else {

2503

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

2504

if(ret == -1){

2505

perror_plus("fstat");

2506

} else {

2507

if(S_ISREG(st.st_mode)

2508

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

2509

ret = fchown(seckey_fd, uid, gid);

2510

if(ret == -1){

2511

perror_plus("fchown");

2512

}

2513

}

2514

}

2515

close(seckey_fd);

2516

}

2517

}

2518

2519

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

2520

int pubkey_fd = open(pubkey, O_RDONLY);

2521

if(pubkey_fd == -1){

2522

perror_plus("open");

2523

} else {

2524

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

2525

if(ret == -1){

2526

perror_plus("fstat");

2527

} else {

2528

if(S_ISREG(st.st_mode)

2529

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

2530

ret = fchown(pubkey_fd, uid, gid);

2531

if(ret == -1){

2532

perror_plus("fchown");

2533

}

2534

}

2535

}

2536

close(pubkey_fd);

2537

}

2538

}

2539

2540

if(dh_params_file != NULL

2541

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

2542

int dhparams_fd = open(dh_params_file, O_RDONLY);

2543

if(dhparams_fd == -1){

2544

perror_plus("open");

2545

} else {

2546

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

2547

if(ret == -1){

2548

perror_plus("fstat");

2549

} else {

2550

if(S_ISREG(st.st_mode)

2551

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

2552

ret = fchown(dhparams_fd, uid, gid);

2553

if(ret == -1){

2554

perror_plus("fchown");

2555

}

2556

}

2557

}

2558

close(dhparams_fd);

2559

}

2560

}

2561

2562

/* Lower privileges */

2563

ret = lower_privileges();

2564

if(ret != 0){

2565

errno = ret;

2566

perror_plus("Failed to lower privileges");

2567

}

2568

}

2569

}

2570

2571

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

2572

{

2573

char *interface = NULL;

2574

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

2575

interface))){

2576

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

2577

and if_nametoindex(interface) == 0){

2578

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

2579

fprintf_plus(stderr, "Not using nonexisting interface"

2580

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

2581

}

2582

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

2583

interface = NULL;

2584

}

1731

2585

}

1732

2586

}

1733

2587

1734

2588

/* Run network hooks */

1735

2589

{

1736

/* Re-raise priviliges */

1737

errno = 0;

1738

ret = seteuid(0);

1739

if(ret == -1){

1740

perror_plus("seteuid");

1741

}

1742

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

1743

goto end;

1744

}

1745

/* Lower privileges */

1746

errno = 0;

1747

ret = seteuid(uid);

1748

if(ret == -1){

1749

perror_plus("seteuid");

1750

}

2590

if(mc.interfaces != NULL){

2591

interfaces_hooks = malloc(mc.interfaces_size);

2592

if(interfaces_hooks == NULL){

2593

perror_plus("malloc");

2594

goto end;

2595

}

2596

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

2597

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

2598

}

2599

run_network_hooks("start", interfaces_hooks != NULL ?

2600

interfaces_hooks : "", delay);

1751

2601

}

1752

2602

1753

2603

if(not debug){

1754

2604

avahi_set_log_function(empty_log);

1755

2605

}

1756

2606

1757

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

1758

struct dirent **direntries;

1759

/* First look for interfaces that are up */

1760

ret = scandir(sys_class_net, &direntries, up_interface,

1761

alphasort);

1762

if(ret == 0){

1763

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

1764

free(direntries);

1765

ret = scandir(sys_class_net, &direntries, good_interface,

1766

alphasort);

1767

}

1768

if(ret >= 1){

1769

/* Pick the first interface returned */

1770

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

1771

if(debug){

1772

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

1773

}

1774

if(interface == NULL){

1775

perror_plus("malloc");

1776

free(direntries);

1777

exitcode = EXIT_FAILURE;

1778

goto end;

1779

}

1780

free(direntries);

1781

} else {

1782

free(direntries);

1783

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

1784

exitcode = EXIT_FAILURE;

1785

goto end;

1786

}

1787

}

1788

1789

2607

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

1790

2608

from the signal handler */

1791

2609

/* Initialize the pseudo-RNG for Avahi */

1792

2610

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

1793

mc.simple_poll = avahi_simple_poll_new();

1794

if(mc.simple_poll == NULL){

2611

simple_poll = avahi_simple_poll_new();

2612

if(simple_poll == NULL){

1795

2613

fprintf_plus(stderr,

1796

2614

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

1797

2615

exitcode = EX_UNAVAILABLE;

1861

2679

}

1862

2680

}

1863

2681

1864

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

1865

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

1866

if_index = (AvahiIfIndex) if_nametoindex(interface);

1867

if(if_index == 0){

1868

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

1869

exitcode = EX_UNAVAILABLE;

1870

goto end;

1871

}

1872

1873

if(quit_now){

1874

goto end;

1875

}

1876

1877

/* Re-raise priviliges */

1878

errno = 0;

1879

ret = seteuid(0);

1880

if(ret == -1){

1881

perror_plus("seteuid");

1882

}

1883

1884

#ifdef __linux__

1885

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1886

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

1887

ret = klogctl(8, NULL, 5);

1888

bool restore_loglevel = true;

1889

if(ret == -1){

1890

restore_loglevel = false;

1891

perror_plus("klogctl");

1892

}

1893

#endif /* __linux__ */

1894

1895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1896

if(sd < 0){

1897

perror_plus("socket");

1898

exitcode = EX_OSERR;

1899

#ifdef __linux__

1900

if(restore_loglevel){

1901

ret = klogctl(7, NULL, 0);

1902

if(ret == -1){

1903

perror_plus("klogctl");

1904

}

1905

}

1906

#endif /* __linux__ */

1907

/* Lower privileges */

1908

errno = 0;

1909

ret = seteuid(uid);

1910

if(ret == -1){

1911

perror_plus("seteuid");

1912

}

1913

goto end;

1914

}

1915

strcpy(network.ifr_name, interface);

1916

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

1917

if(ret == -1){

1918

perror_plus("ioctl SIOCGIFFLAGS");

1919

#ifdef __linux__

1920

if(restore_loglevel){

1921

ret = klogctl(7, NULL, 0);

1922

if(ret == -1){

1923

perror_plus("klogctl");

1924

}

1925

}

1926

#endif /* __linux__ */

1927

exitcode = EX_OSERR;

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

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

1937

network.ifr_flags |= IFF_UP;

1938

take_down_interface = true;

1939

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

1940

if(ret == -1){

1941

take_down_interface = false;

1942

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1943

exitcode = EX_OSERR;

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

2682

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

2683

if(mc.interfaces == NULL){

2684

struct dirent **direntries = NULL;

2685

/* Look for any good interfaces */

2686

ret = scandir(sys_class_net, &direntries, good_interface,

2687

alphasort);

2688

if(ret >= 1){

2689

/* Add all found interfaces to interfaces list */

2690

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

2691

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

2692

direntries[i]->d_name);

2693

if(ret_errno != 0){

2694

errno = ret_errno;

2695

perror_plus("argz_add");

2696

free(direntries[i]);

2697

continue;

2698

}

2699

if(debug){

2700

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

2701

direntries[i]->d_name);

2702

}

2703

free(direntries[i]);

2704

}

2705

free(direntries);

2706

} else {

2707

if(ret == 0){

2708

free(direntries);

2709

}

2710

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

2711

exitcode = EXIT_FAILURE;

2712

goto end;

2713

}

2714

}

2715

2716

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

2717

{

2718

char *interface = NULL;

2719

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

2720

interface))){

2721

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

2722

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

2723

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

2724

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

2725

interface);

2726

interface = NULL;

2727

while((interface = argz_next(mc.interfaces,

2728

mc.interfaces_size, interface))){

2729

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

2730

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

2731

interface);

2732

interface = NULL;

1949

2733

}

1950

2734

}

1951

#endif /* __linux__ */

1952

/* Lower privileges */

1953

errno = 0;

1954

ret = seteuid(uid);

1955

if(ret == -1){

1956

perror_plus("seteuid");

1957

}

1958

goto end;

1959

}

1960

}

1961

/* Sleep checking until interface is running.

1962

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

1963

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

1964

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

1965

if(ret == -1){

1966

perror_plus("ioctl SIOCGIFFLAGS");

1967

} else if(network.ifr_flags & IFF_RUNNING){

1968

2735

break;

1969

2736

}

1970

struct timespec sleeptime = { .tv_nsec = 250000000 };

1971

ret = nanosleep(&sleeptime, NULL);

1972

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

1973

perror_plus("nanosleep");

1974

}

1975

}

1976

if(not take_down_interface){

1977

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

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

}

1983

#ifdef __linux__

1984

if(restore_loglevel){

1985

/* Restores kernel loglevel to default */

1986

ret = klogctl(7, NULL, 0);

1987

if(ret == -1){

1988

perror_plus("klogctl");

1989

}

1990

}

1991

#endif /* __linux__ */

1992

/* Lower privileges */

1993

errno = 0;

1994

/* Lower privileges */

1995

ret = seteuid(uid);

1996

if(ret == -1){

1997

perror_plus("seteuid");

1998

}

2737

bool interface_was_up = interface_is_up(interface);

2738

errno = bring_up_interface(interface, delay);

2739

if(not interface_was_up){

2740

if(errno != 0){

2741

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

2742

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

2743

} else {

2744

errno = argz_add(&interfaces_to_take_down,

2745

&interfaces_to_take_down_size,

2746

interface);

2747

if(errno != 0){

2748

perror_plus("argz_add");

2749

}

2750

}

2751

}

2752

}

2753

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

2754

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

2755

}

2756

}

2757

2758

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

2759

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

2760

if(debug){

2761

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

2762

mc.interfaces);

2763

}

2764

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

1999

2765

}

2000

2766

2001

2767

if(quit_now){

2002

2768

goto end;

2003

2769

}

2004

2770

2005

ret = init_gnutls_global(pubkey, seckey);

2771

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

2006

2772

if(ret == -1){

2007

2773

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

2008

2774

exitcode = EX_UNAVAILABLE;

2015

2781

goto end;

2016

2782

}

2017

2783

2018

if(mkdtemp(tempdir) == NULL){

2784

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

2785

tempdir = mkdtemp(run_tempdir);

2786

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

2787

if(debug){

2788

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

2789

run_tempdir, old_tempdir);

2790

}

2791

tempdir = mkdtemp(old_tempdir);

2792

}

2793

if(tempdir == NULL){

2019

2794

perror_plus("mkdtemp");

2020

2795

goto end;

2021

2796

}

2022

tempdir_created = true;

2023

2797

2024

2798

if(quit_now){

2025

2799

goto end;

2026

2800

}

2027

2801

2028

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

2802

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

2029

2803

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

2030

2804

exitcode = EX_UNAVAILABLE;

2031

2805

goto end;

2041

2815

/* Connect directly, do not use Zeroconf */

2042

2816

/* (Mainly meant for debugging) */

2043

2817

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

2818

2044

2819

if(address == NULL){

2045

2820

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

2046

2821

exitcode = EX_USAGE;

2051

2826

goto end;

2052

2827

}

2053

2828

2054

uint16_t port;

2829

in_port_t port;

2055

2830

errno = 0;

2056

2831

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

2057

2832

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

2058

or tmpmax != (uint16_t)tmpmax){

2833

or tmpmax != (in_port_t)tmpmax){

2059

2834

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

2060

2835

exitcode = EX_USAGE;

2061

2836

goto end;

2062

2837

}

2063

2838

2064

2839

if(quit_now){

2065

2840

goto end;

2066

2841

}

2067

2842

2068

port = (uint16_t)tmpmax;

2843

port = (in_port_t)tmpmax;

2069

2844

*address = '\0';

2070

2845

/* Colon in address indicates IPv6 */

2071

2846

int af;

2087

2862

}

2088

2863

2089

2864

while(not quit_now){

2090

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

2865

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

2866

&mc);

2091

2867

if(quit_now or ret == 0){

2092

2868

break;

2093

2869

}

2095

2871

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

2096

2872

(int)retry_interval);

2097

2873

}

2098

sleep((int)retry_interval);

2874

sleep((unsigned int)retry_interval);

2099

2875

}

2100

2876

2101

if (not quit_now){

2877

if(not quit_now){

2102

2878

exitcode = EXIT_SUCCESS;

2103

2879

}

2104

2880

2119

2895

config.publish_domain = 0;

2120

2896

2121

2897

/* Allocate a new server */

2122

mc.server = avahi_server_new(avahi_simple_poll_get

2123

(mc.simple_poll), &config, NULL,

2124

NULL, &error);

2898

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2899

&config, NULL, NULL, &ret);

2125

2900

2126

2901

/* Free the Avahi configuration data */

2127

2902

avahi_server_config_free(&config);

2130

2905

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

2131

2906

if(mc.server == NULL){

2132

2907

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

2133

avahi_strerror(error));

2908

avahi_strerror(ret));

2134

2909

exitcode = EX_UNAVAILABLE;

2135

2910

goto end;

2136

2911

}

2142

2917

/* Create the Avahi service browser */

2143

2918

sb = avahi_s_service_browser_new(mc.server, if_index,

2144

2919

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2145

NULL, 0, browse_callback, NULL);

2920

NULL, 0, browse_callback,

2921

(void *)&mc);

2146

2922

if(sb == NULL){

2147

2923

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

2148

2924

avahi_strerror(avahi_server_errno(mc.server)));

2159

2935

if(debug){

2160

2936

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

2161

2937

}

2162

2163

ret = avahi_loop_with_timeout(mc.simple_poll,

2164

(int)(retry_interval * 1000));

2938

2939

ret = avahi_loop_with_timeout(simple_poll,

2940

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

2165

2941

if(debug){

2166

2942

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

2167

2943

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

2174

2950

}

2175

2951

2176

2952

/* Cleanup things */

2953

free(mc.interfaces);

2954

2177

2955

if(sb != NULL)

2178

2956

avahi_s_service_browser_free(sb);

2179

2957

2180

2958

if(mc.server != NULL)

2181

2959

avahi_server_free(mc.server);

2182

2960

2183

if(mc.simple_poll != NULL)

2184

avahi_simple_poll_free(mc.simple_poll);

2961

if(simple_poll != NULL)

2962

avahi_simple_poll_free(simple_poll);

2185

2963

2186

2964

if(gnutls_initialized){

2187

2965

gnutls_certificate_free_credentials(mc.cred);

2188

gnutls_global_deinit();

2189

2966

gnutls_dh_params_deinit(mc.dh_params);

2190

2967

}

2191

2968

2192

2969

if(gpgme_initialized){

2193

2970

gpgme_release(mc.ctx);

2194

2971

}

2195

2972

2196

2973

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

2197

2974

has seen */

2198

2975

if(mc.current_server != NULL){

2199

2976

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

2200

2977

while(mc.current_server != NULL){

2201

2978

server *next = mc.current_server->next;

2979

#ifdef __GNUC__

2980

#pragma GCC diagnostic push

2981

#pragma GCC diagnostic ignored "-Wcast-qual"

2982

#endif

2983

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

2984

#ifdef __GNUC__

2985

#pragma GCC diagnostic pop

2986

#endif

2202

2987

free(mc.current_server);

2203

2988

mc.current_server = next;

2204

2989

}

2205

2990

}

2206

2991

2207

/* Re-raise priviliges */

2992

/* Re-raise privileges */

2208

2993

{

2209

errno = 0;

2210

ret = seteuid(0);

2211

if(ret == -1){

2212

perror_plus("seteuid");

2213

}

2214

/* Run network hooks */

2215

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

2216

goto end;

2994

ret = raise_privileges();

2995

if(ret != 0){

2996

errno = ret;

2997

perror_plus("Failed to raise privileges");

2998

} else {

2999

3000

/* Run network hooks */

3001

run_network_hooks("stop", interfaces_hooks != NULL ?

3002

interfaces_hooks : "", delay);

3003

3004

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

3005

{

3006

char *interface = NULL;

3007

while((interface=argz_next(interfaces_to_take_down,

3008

interfaces_to_take_down_size,

3009

interface))){

3010

ret = take_down_interface(interface);

3011

if(ret != 0){

3012

errno = ret;

3013

perror_plus("Failed to take down interface");

3014

}

3015

}

3016

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

3017

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

3018

" down\n");

3019

}

3020

}

2217

3021

}

2218

3022

2219

/* Take down the network interface */

2220

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

2221

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

2222

if(ret == -1){

2223

perror_plus("ioctl SIOCGIFFLAGS");

2224

} else if(network.ifr_flags & IFF_UP){

2225

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

2226

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

2227

if(ret == -1){

2228

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2229

}

2230

}

2231

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

2232

if(ret == -1){

2233

perror_plus("close");

2234

}

3023

ret = lower_privileges_permanently();

3024

if(ret != 0){

3025

errno = ret;

3026

perror_plus("Failed to lower privileges permanently");

2235

3027

}

2236

3028

}

2237

/* Lower privileges permanently */

2238

errno = 0;

2239

ret = setuid(uid);

2240

if(ret == -1){

2241

perror_plus("setuid");

3029

3030

free(interfaces_to_take_down);

3031

free(interfaces_hooks);

3032

3033

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

3034

uintmax_t level){

3035

struct dirent **direntries = NULL;

3036

int dret;

3037

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

3038

O_RDONLY

3039

| O_NOFOLLOW

3040

| O_DIRECTORY

3041

| O_PATH));

3042

if(dir_fd == -1){

3043

perror_plus("open");

3044

}

3045

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

3046

notdotentries, alphasort);

3047

if(numentries >= 0){

3048

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

3049

if(debug){

3050

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

3051

dirname, direntries[i]->d_name);

3052

}

3053

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

3054

if(dret == -1){

3055

if(errno == EISDIR){

3056

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

3057

AT_REMOVEDIR);

3058

}

3059

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

3060

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

3061

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

3062

/* Recurse only in this special case */

3063

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

3064

dret = 0;

3065

}

3066

if(dret == -1){

3067

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

3068

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

3069

}

3070

}

3071

free(direntries[i]);

3072

}

3073

3074

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

3075

free(direntries);

3076

if(numentries == -1){

3077

perror_plus("scandirat");

3078

}

3079

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3080

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

3081

perror_plus("rmdir");

3082

}

3083

} else {

3084

perror_plus("scandirat");

3085

}

3086

close(dir_fd);

2242

3087

}

2243

3088

2244

3089

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

2245

if(tempdir_created){

2246

struct dirent **direntries = NULL;

2247

struct dirent *direntry = NULL;

2248

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

2249

alphasort);

2250

if (numentries > 0){

2251

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

2252

direntry = direntries[i];

2253

char *fullname = NULL;

2254

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

2255

direntry->d_name);

2256

if(ret < 0){

2257

perror_plus("asprintf");

2258

continue;

2259

}

2260

ret = remove(fullname);

2261

if(ret == -1){

2262

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

2263

strerror(errno));

2264

}

2265

free(fullname);

2266

}

2267

}

2268

2269

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

2270

free(direntries);

2271

if (numentries == -1){

2272

perror_plus("scandir");

2273

}

2274

ret = rmdir(tempdir);

2275

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

2276

perror_plus("rmdir");

2277

}

3090

if(tempdir != NULL){

3091

clean_dir_at(-1, tempdir, 0);

2278

3092

}

2279

3093

2280

3094

if(quit_now){