/mandos/trunk : revision 302

9

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

10

*

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* Everything else is

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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

30

*/

31

32

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

33

#ifndef _LARGEFILE_SOURCE

34

33

#define _LARGEFILE_SOURCE

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

34

#define _FILE_OFFSET_BITS 64

38

#endif

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35

40

36

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

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37

42

38

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

43

stdout, ferror(), remove() */

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stdout, ferror(), sscanf(),

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remove() */

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41

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

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42

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

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srand() */

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

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

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47

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

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

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

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49

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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SOCK_STREAM, INET6_ADDRSTRLEN,

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uid_t, gid_t, open(), opendir(),

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DIR */

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

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

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inet_pton(), connect() */

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struct in6_addr, inet_pton(),

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connect() */

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58

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

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

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*/

62

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

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strtoimax() */

61

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

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62

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

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63

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

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

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

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65

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

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SIOCSIFFLAGS, if_indextoname(),

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67

if_nametoindex(), IF_NAMESIZE */

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#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN

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*/

68

#include <netinet/in.h>

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69

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

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

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setgid(), pause() */

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getuid(), getgid(), setuid(),

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setgid() */

76

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

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

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

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74

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

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75

argp_state, struct argp,

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argp_parse(), ARGP_KEY_ARG,

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77

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

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#include <signal.h> /* sigemptyset(), sigaddset(),

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sigaction(), SIGTERM, sig_atomic_t,

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raise() */

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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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78

#ifdef __linux__

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79

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

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#endif /* __linux__ */

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#endif

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81

92

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/* Avahi */

93

83

/* All Avahi types, constants and functions

127

117

static const char mandos_protocol_version[] = "1";

128

118

const char *argp_program_version = "mandos-client " VERSION;

129

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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

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

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char *connect_to = NULL;

132

120

133

121

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

134

122

typedef struct {

141

129

gpgme_ctx_t ctx;

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130

} mandos_context;

143

131

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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":!CTYPE-X.509:+CTYPE-OPENPGP" };

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149

sig_atomic_t quit_now = 0;

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int signal_received = 0;

151

152

132

/*

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* Make additional room in "buffer" for at least BUFFER_SIZE more

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

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* Make room in "buffer" for at least BUFFER_SIZE additional bytes.

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* "buffer_capacity" is how much is currently allocated,

155

135

* "buffer_length" is how much is already used.

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136

*/

157

size_t incbuffer(char **buffer, size_t buffer_length,

137

size_t adjustbuffer(char **buffer, size_t buffer_length,

158

138

size_t buffer_capacity){

159

139

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

140

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

169

149

/*

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150

* Initialize GPGME.

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151

*/

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static bool init_gpgme(const char *seckey,

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static bool init_gpgme(mandos_context *mc, const char *seckey,

173

153

const char *pubkey, const char *tempdir){

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int ret;

174

155

gpgme_error_t rc;

175

156

gpgme_engine_info_t engine_info;

176

157

179

160

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

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161

*/

181

162

bool import_key(const char *filename){

182

int ret;

183

163

int fd;

184

164

gpgme_data_t pgp_data;

185

165

196

176

return false;

197

177

}

198

178

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rc = gpgme_op_import(mc.ctx, pgp_data);

179

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

200

180

if(rc != GPG_ERR_NO_ERROR){

201

181

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

202

182

gpgme_strsource(rc), gpgme_strerror(rc));

212

192

}

213

193

214

194

if(debug){

215

fprintf(stderr, "Initializing GPGME\n");

195

fprintf(stderr, "Initialize gpgme\n");

216

196

}

217

197

218

198

/* Init GPGME */

245

225

}

246

226

247

227

/* Create new GPGME "context" */

248

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

228

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

249

229

if(rc != GPG_ERR_NO_ERROR){

250

230

fprintf(stderr, "bad gpgme_new: %s: %s\n",

251

231

gpgme_strsource(rc), gpgme_strerror(rc));

256

236

return false;

257

237

}

258

238

259

return true;

239

return true;

260

240

}

261

241

262

242

/*

263

243

* Decrypt OpenPGP data.

264

244

* Returns -1 on error

265

245

*/

266

static ssize_t pgp_packet_decrypt(const char *cryptotext,

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

267

248

size_t crypto_size,

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char **plaintext){

269

250

gpgme_data_t dh_crypto, dh_plain;

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297

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

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279

data buffer */

299

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

280

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

300

281

if(rc != GPG_ERR_NO_ERROR){

301

282

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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284

plaintext_length = -1;

304

285

if(debug){

305

286

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

287

result = gpgme_op_decrypt_result(mc->ctx);

307

288

if(result == NULL){

308

289

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

309

290

} else {

316

297

}

317

298

gpgme_recipient_t recipient;

318

299

recipient = result->recipients;

319

while(recipient != NULL){

320

fprintf(stderr, "Public key algorithm: %s\n",

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

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fprintf(stderr, "Secret key available: %s\n",

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recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

326

recipient = recipient->next;

300

if(recipient){

301

while(recipient != NULL){

302

fprintf(stderr, "Public key algorithm: %s\n",

303

gpgme_pubkey_algo_name(recipient->pubkey_algo));

304

fprintf(stderr, "Key ID: %s\n", recipient->keyid);

305

fprintf(stderr, "Secret key available: %s\n",

306

recipient->status == GPG_ERR_NO_SECKEY

307

? "No" : "Yes");

308

recipient = recipient->next;

309

}

327

310

}

328

311

}

329

312

}

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344

327

*plaintext = NULL;

345

328

while(true){

346

plaintext_capacity = incbuffer(plaintext,

329

plaintext_capacity = adjustbuffer(plaintext,

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(size_t)plaintext_length,

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331

plaintext_capacity);

349

332

if(plaintext_capacity == 0){

350

perror("incbuffer");

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perror("adjustbuffer");

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334

plaintext_length = -1;

352

335

goto decrypt_end;

353

336

}

399

382

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

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383

}

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384

402

static int init_gnutls_global(const char *pubkeyfilename,

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static int init_gnutls_global(mandos_context *mc,

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const char *pubkeyfilename,

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387

const char *seckeyfilename){

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int ret;

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389

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407

}

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408

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/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

410

gnutls_certificate_allocate_credentials(&mc->cred);

427

411

if(ret != GNUTLS_E_SUCCESS){

428

412

fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning

429

from

430

-Wunreachable-code

431

*/

413

* from

414

* -Wunreachable-code

415

*/

432

416

safer_gnutls_strerror(ret));

433

417

gnutls_global_deinit();

434

418

return -1;

441

425

}

442

426

443

427

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

428

(mc->cred, pubkeyfilename, seckeyfilename,

445

429

GNUTLS_OPENPGP_FMT_BASE64);

446

430

if(ret != GNUTLS_E_SUCCESS){

447

431

fprintf(stderr,

453

437

}

454

438

455

439

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

440

ret = gnutls_dh_params_init(&mc->dh_params);

457

441

if(ret != GNUTLS_E_SUCCESS){

458

442

fprintf(stderr, "Error in GnuTLS DH parameter initialization:"

459

443

" %s\n", safer_gnutls_strerror(ret));

460

444

goto globalfail;

461

445

}

462

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

446

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

463

447

if(ret != GNUTLS_E_SUCCESS){

464

448

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

465

449

safer_gnutls_strerror(ret));

466

450

goto globalfail;

467

451

}

468

452

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

453

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

470

454

471

455

return 0;

472

456

473

457

globalfail:

474

458

475

gnutls_certificate_free_credentials(mc.cred);

459

gnutls_certificate_free_credentials(mc->cred);

476

460

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

461

gnutls_dh_params_deinit(mc->dh_params);

478

462

return -1;

479

463

}

480

464

481

static int init_gnutls_session(gnutls_session_t *session){

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

482

467

int ret;

483

468

/* GnuTLS session creation */

484

do {

485

ret = gnutls_init(session, GNUTLS_SERVER);

486

if(quit_now){

487

return -1;

488

}

489

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

469

ret = gnutls_init(session, GNUTLS_SERVER);

490

470

if(ret != GNUTLS_E_SUCCESS){

491

471

fprintf(stderr, "Error in GnuTLS session initialization: %s\n",

492

472

safer_gnutls_strerror(ret));

494

474

495

475

{

496

476

const char *err;

497

do {

498

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

499

if(quit_now){

500

gnutls_deinit(*session);

501

return -1;

502

}

503

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

477

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

504

478

if(ret != GNUTLS_E_SUCCESS){

505

479

fprintf(stderr, "Syntax error at: %s\n", err);

506

480

fprintf(stderr, "GnuTLS error: %s\n",

510

484

}

511

485

}

512

486

513

do {

514

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

516

if(quit_now){

517

gnutls_deinit(*session);

518

return -1;

519

}

520

} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);

487

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

521

489

if(ret != GNUTLS_E_SUCCESS){

522

490

fprintf(stderr, "Error setting GnuTLS credentials: %s\n",

523

491

safer_gnutls_strerror(ret));

526

494

}

527

495

528

496

/* ignore client certificate if any. */

529

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

497

gnutls_certificate_server_set_request(*session,

498

GNUTLS_CERT_IGNORE);

530

499

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

532

501

533

502

return 0;

534

503

}

540

509

/* Called when a Mandos server is found */

541

510

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

542

511

AvahiIfIndex if_index,

543

int af){

544

int ret, tcp_sd = -1;

512

mandos_context *mc){

513

int ret, tcp_sd;

545

514

ssize_t sret;

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

515

union { struct sockaddr in; struct sockaddr_in6 in6; } to;

550

516

char *buffer = NULL;

551

char *decrypted_buffer = NULL;

517

char *decrypted_buffer;

552

518

size_t buffer_length = 0;

553

519

size_t buffer_capacity = 0;

520

ssize_t decrypted_buffer_size;

554

521

size_t written;

555

int retval = -1;

522

int retval = 0;

523

char interface[IF_NAMESIZE];

556

524

gnutls_session_t session;

557

int pf; /* Protocol family */

558

559

errno = 0;

560

561

if(quit_now){

562

errno = EINTR;

563

return -1;

564

}

565

566

switch(af){

567

case AF_INET6:

568

pf = PF_INET6;

569

break;

570

case AF_INET:

571

pf = PF_INET;

572

break;

573

default:

574

fprintf(stderr, "Bad address family: %d\n", af);

575

errno = EINVAL;

576

return -1;

577

}

578

579

ret = init_gnutls_session(&session);

525

526

ret = init_gnutls_session(mc, &session);

580

527

if(ret != 0){

581

528

return -1;

582

529

}

583

530

584

531

if(debug){

585

fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16

532

fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16

586

533

"\n", ip, port);

587

534

}

588

535

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

536

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

590

537

if(tcp_sd < 0){

591

int e = errno;

592

538

perror("socket");

593

errno = e;

594

goto mandos_end;

539

return -1;

595

540

}

596

541

597

if(quit_now){

598

errno = EINTR;

599

goto mandos_end;

542

if(debug){

543

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

544

perror("if_indextoname");

545

return -1;

546

}

547

fprintf(stderr, "Binding to interface %s\n", interface);

600

548

}

601

549

602

550

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

603

if(af == AF_INET6){

604

to.in6.sin6_family = (sa_family_t)af;

605

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

606

} else { /* IPv4 */

607

to.in.sin_family = (sa_family_t)af;

608

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

609

}

551

to.in6.sin6_family = AF_INET6;

552

/* It would be nice to have a way to detect if we were passed an

553

IPv4 address here. Now we assume an IPv6 address. */

554

ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);

610

555

if(ret < 0 ){

611

int e = errno;

612

556

perror("inet_pton");

613

errno = e;

614

goto mandos_end;

557

return -1;

615

558

}

616

559

if(ret == 0){

617

int e = errno;

618

560

fprintf(stderr, "Bad address: %s\n", ip);

619

errno = e;

620

goto mandos_end;

561

return -1;

621

562

}

622

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

630

if(if_index == AVAHI_IF_UNSPEC){

631

fprintf(stderr, "An IPv6 link-local address is incomplete"

632

" without a network interface\n");

633

errno = EINVAL;

634

goto mandos_end;

635

}

636

/* Set the network interface number as scope */

637

to.in6.sin6_scope_id = (uint32_t)if_index;

638

}

639

} else {

640

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

563

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

641

564

-Wconversion and

642

565

-Wunreachable-code */

643

}

644

566

645

if(quit_now){

646

errno = EINTR;

647

goto mandos_end;

648

}

567

to.in6.sin6_scope_id = (uint32_t)if_index;

649

568

650

569

if(debug){

651

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

652

char interface[IF_NAMESIZE];

653

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

654

perror("if_indextoname");

655

} else {

656

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

657

ip, interface, port);

658

}

659

} else {

660

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

661

port);

662

}

663

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

665

const char *pcret;

666

if(af == AF_INET6){

667

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

668

sizeof(addrstr));

669

} else {

670

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

671

sizeof(addrstr));

672

}

673

if(pcret == NULL){

570

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

571

port);

572

char addrstr[INET6_ADDRSTRLEN] = "";

573

if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,

574

sizeof(addrstr)) == NULL){

674

575

perror("inet_ntop");

675

576

} else {

676

577

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

679

580

}

680

581

}

681

582

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

687

if(af == AF_INET6){

688

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

689

} else {

690

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

691

}

583

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

692

584

if(ret < 0){

693

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

694

int e = errno;

695

perror("connect");

696

errno = e;

697

}

698

goto mandos_end;

699

}

700

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

585

perror("connect");

586

return -1;

704

587

}

705

588

706

589

const char *out = mandos_protocol_version;

710

593

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

711

594

out_size - written));

712

595

if(ret == -1){

713

int e = errno;

714

596

perror("write");

715

errno = e;

597

retval = -1;

716

598

goto mandos_end;

717

599

}

718

600

written += (size_t)ret;

726

608

break;

727

609

}

728

610

}

729

730

if(quit_now){

731

errno = EINTR;

732

goto mandos_end;

733

}

734

611

}

735

612

736

613

if(debug){

737

614

fprintf(stderr, "Establishing TLS session with %s\n", ip);

738

615

}

739

616

740

if(quit_now){

741

errno = EINTR;

742

goto mandos_end;

743

}

744

745

617

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

746

618

747

if(quit_now){

748

errno = EINTR;

749

goto mandos_end;

750

}

751

752

do {

619

do{

753

620

ret = gnutls_handshake(session);

754

if(quit_now){

755

errno = EINTR;

756

goto mandos_end;

757

}

758

621

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

759

622

760

623

if(ret != GNUTLS_E_SUCCESS){

762

625

fprintf(stderr, "*** GnuTLS Handshake failed ***\n");

763

626

gnutls_perror(ret);

764

627

}

765

errno = EPROTO;

628

retval = -1;

766

629

goto mandos_end;

767

630

}

768

631

769

632

/* Read OpenPGP packet that contains the wanted password */

770

633

771

634

if(debug){

772

fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",

635

fprintf(stderr, "Retrieving pgp encrypted password from %s\n",

773

636

ip);

774

637

}

775

638

776

639

while(true){

777

778

if(quit_now){

779

errno = EINTR;

780

goto mandos_end;

781

}

782

783

buffer_capacity = incbuffer(&buffer, buffer_length,

640

buffer_capacity = adjustbuffer(&buffer, buffer_length,

784

641

buffer_capacity);

785

642

if(buffer_capacity == 0){

786

int e = errno;

787

perror("incbuffer");

788

errno = e;

789

goto mandos_end;

790

}

791

792

if(quit_now){

793

errno = EINTR;

643

perror("adjustbuffer");

644

retval = -1;

794

645

goto mandos_end;

795

646

}

796

647

805

656

case GNUTLS_E_AGAIN:

806

657

break;

807

658

case GNUTLS_E_REHANDSHAKE:

808

do {

659

do{

809

660

ret = gnutls_handshake(session);

810

811

if(quit_now){

812

errno = EINTR;

813

goto mandos_end;

814

}

815

661

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

816

662

if(ret < 0){

817

663

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

818

664

gnutls_perror(ret);

819

errno = EPROTO;

665

retval = -1;

820

666

goto mandos_end;

821

667

}

822

668

break;

823

669

default:

824

670

fprintf(stderr, "Unknown error while reading data from"

825

671

" encrypted session with Mandos server\n");

672

retval = -1;

826

673

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

errno = EIO;

828

674

goto mandos_end;

829

675

}

830

676

} else {

836

682

fprintf(stderr, "Closing TLS session\n");

837

683

}

838

684

839

if(quit_now){

840

errno = EINTR;

841

goto mandos_end;

842

}

843

844

do {

845

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

846

if(quit_now){

847

errno = EINTR;

848

goto mandos_end;

849

}

850

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

685

gnutls_bye(session, GNUTLS_SHUT_RDWR);

851

686

852

687

if(buffer_length > 0){

853

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

688

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

855

689

buffer_length,

856

690

&decrypted_buffer);

857

691

if(decrypted_buffer_size >= 0){

858

859

692

written = 0;

860

693

while(written < (size_t) decrypted_buffer_size){

861

if(quit_now){

862

errno = EINTR;

863

goto mandos_end;

864

}

865

866

694

ret = (int)fwrite(decrypted_buffer + written, 1,

867

695

(size_t)decrypted_buffer_size - written,

868

696

stdout);

869

697

if(ret == 0 and ferror(stdout)){

870

int e = errno;

871

698

if(debug){

872

699

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

873

700

strerror(errno));

874

701

}

875

errno = e;

876

goto mandos_end;

702

retval = -1;

703

break;

877

704

}

878

705

written += (size_t)ret;

879

706

}

880

retval = 0;

707

free(decrypted_buffer);

708

} else {

709

retval = -1;

881

710

}

711

} else {

712

retval = -1;

882

713

}

883

714

884

715

/* Shutdown procedure */

885

716

886

717

mandos_end:

887

{

888

int e = errno;

889

free(decrypted_buffer);

890

free(buffer);

891

if(tcp_sd >= 0){

892

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

893

}

894

if(ret == -1){

895

if(e == 0){

896

e = errno;

897

}

898

perror("close");

899

}

900

gnutls_deinit(session);

901

if(quit_now){

902

e = EINTR;

903

retval = -1;

904

}

905

errno = e;

718

free(buffer);

719

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

720

if(ret == -1){

721

perror("close");

906

722

}

723

gnutls_deinit(session);

907

724

return retval;

908

725

}

909

726

910

727

static void resolve_callback(AvahiSServiceResolver *r,

911

728

AvahiIfIndex interface,

912

AvahiProtocol proto,

729

AVAHI_GCC_UNUSED AvahiProtocol protocol,

913

730

AvahiResolverEvent event,

914

731

const char *name,

915

732

const char *type,

920

737

AVAHI_GCC_UNUSED AvahiStringList *txt,

921

738

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

739

flags,

923

AVAHI_GCC_UNUSED void* userdata){

740

void* userdata){

741

mandos_context *mc = userdata;

924

742

assert(r);

925

743

926

744

/* Called whenever a service has been resolved successfully or

927

745

timed out */

928

746

929

if(quit_now){

930

return;

931

}

932

933

747

switch(event){

934

748

default:

935

749

case AVAHI_RESOLVER_FAILURE:

936

750

fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"

937

751

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

938

avahi_strerror(avahi_server_errno(mc.server)));

752

avahi_strerror(avahi_server_errno(mc->server)));

939

753

break;

940

754

941

755

case AVAHI_RESOLVER_FOUND:

947

761

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

948

762

ip, (intmax_t)interface, port);

949

763

}

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

764

int ret = start_mandos_communication(ip, port, interface, mc);

952

765

if(ret == 0){

953

avahi_simple_poll_quit(mc.simple_poll);

766

avahi_simple_poll_quit(mc->simple_poll);

954

767

}

955

768

}

956

769

}

966

779

const char *domain,

967

780

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

781

flags,

969

AVAHI_GCC_UNUSED void* userdata){

782

void* userdata){

783

mandos_context *mc = userdata;

970

784

assert(b);

971

785

972

786

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

973

787

is removed from the LAN */

974

788

975

if(quit_now){

976

return;

977

}

978

979

789

switch(event){

980

790

default:

981

791

case AVAHI_BROWSER_FAILURE:

982

792

983

793

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

794

avahi_strerror(avahi_server_errno(mc->server)));

795

avahi_simple_poll_quit(mc->simple_poll);

986

796

return;

987

797

988

798

case AVAHI_BROWSER_NEW:

991

801

the callback function is called the Avahi server will free the

992

802

resolver for us. */

993

803

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

804

if(!(avahi_s_service_resolver_new(mc->server, interface,

805

protocol, name, type, domain,

806

AVAHI_PROTO_INET6, 0,

807

resolve_callback, mc)))

997

808

fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",

998

name, avahi_strerror(avahi_server_errno(mc.server)));

809

name, avahi_strerror(avahi_server_errno(mc->server)));

999

810

break;

1000

811

1001

812

case AVAHI_BROWSER_REMOVE:

1010

821

}

1011

822

}

1012

823

1013

/* stop main loop after sigterm has been called */

1014

static void handle_sigterm(int sig){

1015

if(quit_now){

1016

return;

1017

}

1018

quit_now = 1;

1019

signal_received = sig;

1020

int old_errno = errno;

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1023

}

1024

errno = old_errno;

1025

}

1026

1027

/*

1028

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

1029

* corresponds to an acceptable network device.

1030

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

1031

*/

1032

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

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

1042

return 0;

1043

}

1044

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1050

/* read line from flags_fd */

1051

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1052

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1053

flagstring[(size_t)to_read] = '\0';

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1070

break;

1071

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

tmpmax = strtoimax(flagstring, &tmp, 0);

1078

if(errno != 0 or tmp == flagstring or (*tmp != '\0'

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

fprintf(stderr, "Rejecting loopback interface \"%s\"\n",

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

/* Accept point-to-point devices only if connect_to is specified */

1099

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1100

if(debug){

1101

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

/* Otherwise, reject non-broadcast-capable devices */

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1117

if_entry->d_name);

1118

}

1119

return 1;

1120

}

1121

1122

824

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

1123

825

AvahiSServiceBrowser *sb = NULL;

1124

826

int error;

1125

827

int ret;

1126

828

intmax_t tmpmax;

1127

char *tmp;

829

int numchars;

1128

830

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

831

const char *interface = "eth0";

1130

832

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

833

int sd;

1133

834

uid_t uid;

1134

835

gid_t gid;

836

char *connect_to = NULL;

1135

837

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

1136

838

bool tempdir_created = false;

1137

839

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

840

const char *seckey = PATHDIR "/" SECKEY;

1139

841

const char *pubkey = PATHDIR "/" PUBKEY;

1140

842

843

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

844

.dh_bits = 1024, .priority = "SECURE256"

845

":!CTYPE-X.509:+CTYPE-OPENPGP" };

1141

846

bool gnutls_initialized = false;

1142

847

bool gpgme_initialized = false;

1143

float delay = 2.5f;

1144

1145

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1147

1148

uid = getuid();

1149

gid = getgid();

1150

1151

/* Lower any group privileges we might have, just to be safe */

1152

errno = 0;

1153

ret = setgid(gid);

1154

if(ret == -1){

1155

perror("setgid");

1156

}

1157

1158

/* Lower user privileges (temporarily) */

1159

errno = 0;

1160

ret = seteuid(uid);

1161

if(ret == -1){

1162

perror("seteuid");

1163

}

1164

1165

if(quit_now){

1166

goto end;

1167

}

848

double delay = 2.5;

1168

849

1169

850

{

1170

851

struct argp_option options[] = {

1176

857

.group = 1 },

1177

858

{ .name = "interface", .key = 'i',

1178

859

.arg = "NAME",

1179

.doc = "Network interface that will be used to search for"

1180

" Mandos servers",

860

.doc = "Interface that will be used to search for Mandos"

861

" servers",

1181

862

.group = 1 },

1182

863

{ .name = "seckey", .key = 's',

1183

864

.arg = "FILE",

1200

881

.arg = "SECONDS",

1201

882

.doc = "Maximum delay to wait for interface startup",

1202

883

.group = 2 },

1203

/*

1204

* These reproduce what we would get without ARGP_NO_HELP

1205

*/

1206

{ .name = "help", .key = '?',

1207

.doc = "Give this help list", .group = -1 },

1208

{ .name = "usage", .key = -3,

1209

.doc = "Give a short usage message", .group = -1 },

1210

{ .name = "version", .key = 'V',

1211

.doc = "Print program version", .group = -1 },

1212

884

{ .name = NULL }

1213

885

};

1214

886

1215

887

error_t parse_opt(int key, char *arg,

1216

888

struct argp_state *state){

1217

errno = 0;

1218

889

switch(key){

1219

890

case 128: /* --debug */

1220

891

debug = true;

1232

903

pubkey = arg;

1233

904

break;

1234

905

case 129: /* --dh-bits */

1235

errno = 0;

1236

tmpmax = strtoimax(arg, &tmp, 10);

1237

if(errno != 0 or tmp == arg or *tmp != '\0'

1238

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1239

argp_error(state, "Bad number of DH bits");

906

ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);

907

if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax

908

or arg[numchars] != '\0'){

909

fprintf(stderr, "Bad number of DH bits\n");

910

exit(EXIT_FAILURE);

1240

911

}

1241

912

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

1242

913

break;

1244

915

mc.priority = arg;

1245

916

break;

1246

917

case 131: /* --delay */

1247

errno = 0;

1248

delay = strtof(arg, &tmp);

1249

if(errno != 0 or tmp == arg or *tmp != '\0'){

1250

argp_error(state, "Bad delay");

918

ret = sscanf(arg, "%lf%n", &delay, &numchars);

919

if(ret < 1 or arg[numchars] != '\0'){

920

fprintf(stderr, "Bad delay\n");

921

exit(EXIT_FAILURE);

1251

922

}

1252

923

break;

1253

/*

1254

* These reproduce what we would get without ARGP_NO_HELP

1255

*/

1256

case '?': /* --help */

1257

argp_state_help(state, state->out_stream,

1258

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1259

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1260

case -3: /* --usage */

1261

argp_state_help(state, state->out_stream,

1262

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

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

1264

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

1265

exit(argp_err_exit_status);

924

case ARGP_KEY_ARG:

925

argp_usage(state);

926

case ARGP_KEY_END:

1266

927

break;

1267

928

default:

1268

929

return ARGP_ERR_UNKNOWN;

1269

930

}

1270

return errno;

931

return 0;

1271

932

}

1272

933

1273

934

struct argp argp = { .options = options, .parser = parse_opt,

1274

935

.args_doc = "",

1275

936

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

1276

937

" passwords from a Mandos server" };

1277

ret = argp_parse(&argp, argc, argv,

1278

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1279

switch(ret){

1280

case 0:

1281

break;

1282

case ENOMEM:

1283

default:

1284

errno = ret;

1285

perror("argp_parse");

1286

exitcode = EX_OSERR;

1287

goto end;

1288

case EINVAL:

1289

exitcode = EX_USAGE;

1290

goto end;

1291

}

1292

}

1293

1294

if(not debug){

1295

avahi_set_log_function(empty_log);

1296

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

938

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

939

if(ret == ARGP_ERR_UNKNOWN){

940

fprintf(stderr, "Unknown error while parsing arguments\n");

1318

941

exitcode = EXIT_FAILURE;

1319

942

goto end;

1320

943

}

1321

944

}

1322

945

1323

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

1324

from the signal handler */

1325

/* Initialize the pseudo-RNG for Avahi */

1326

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

1327

mc.simple_poll = avahi_simple_poll_new();

1328

if(mc.simple_poll == NULL){

1329

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

1330

exitcode = EX_UNAVAILABLE;

1331

goto end;

1332

}

1333

1334

sigemptyset(&sigterm_action.sa_mask);

1335

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1336

if(ret == -1){

1337

perror("sigaddset");

1338

exitcode = EX_OSERR;

1339

goto end;

1340

}

1341

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1342

if(ret == -1){

1343

perror("sigaddset");

1344

exitcode = EX_OSERR;

1345

goto end;

1346

}

1347

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1348

if(ret == -1){

1349

perror("sigaddset");

1350

exitcode = EX_OSERR;

1351

goto end;

1352

}

1353

/* Need to check if the handler is SIG_IGN before handling:

1354

| [[info:libc:Initial Signal Actions]] |

1355

| [[info:libc:Basic Signal Handling]] |

1356

*/

1357

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1358

if(ret == -1){

1359

perror("sigaction");

1360

return EX_OSERR;

1361

}

1362

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

ret = sigaction(SIGINT, &sigterm_action, NULL);

1364

if(ret == -1){

1365

perror("sigaction");

1366

exitcode = EX_OSERR;

1367

goto end;

1368

}

1369

}

1370

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1371

if(ret == -1){

1372

perror("sigaction");

1373

return EX_OSERR;

1374

}

1375

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1377

if(ret == -1){

1378

perror("sigaction");

1379

exitcode = EX_OSERR;

1380

goto end;

1381

}

1382

}

1383

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1384

if(ret == -1){

1385

perror("sigaction");

1386

return EX_OSERR;

1387

}

1388

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1390

if(ret == -1){

1391

perror("sigaction");

1392

exitcode = EX_OSERR;

1393

goto end;

1394

}

1395

}

1396

1397

946

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

947

{

1417

948

#ifdef __linux__

1418

949

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

950

messages to mess up the prompt */

1420

951

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

952

if(ret == -1){

1423

restore_loglevel = false;

1424

953

perror("klogctl");

1425

954

}

1426

#endif /* __linux__ */

955

#endif

1427

956

1428

957

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

958

if(sd < 0){

1430

959

perror("socket");

1431

exitcode = EX_OSERR;

960

exitcode = EXIT_FAILURE;

1432

961

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

962

ret = klogctl(7, NULL, 0);

1443

963

if(ret == -1){

1444

perror("seteuid");

964

perror("klogctl");

1445

965

}

966

#endif

1446

967

goto end;

1447

968

}

1448

969

strcpy(network.ifr_name, interface);

1450

971

if(ret == -1){

1451

972

perror("ioctl SIOCGIFFLAGS");

1452

973

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

974

ret = klogctl(7, NULL, 0);

1464

975

if(ret == -1){

1465

perror("seteuid");

976

perror("klogctl");

1466

977

}

978

#endif

979

exitcode = EXIT_FAILURE;

1467

980

goto end;

1468

981

}

1469

982

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

1470

983

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

984

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

1473

985

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

986

perror("ioctl SIOCSIFFLAGS");

987

exitcode = EXIT_FAILURE;

1477

988

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

1482

}

1483

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

989

ret = klogctl(7, NULL, 0);

1488

990

if(ret == -1){

1489

perror("seteuid");

991

perror("klogctl");

1490

992

}

993

#endif

1491

994

goto end;

1492

995

}

1493

996

}

1505

1008

perror("nanosleep");

1506

1009

}

1507

1010

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1011

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

1012

if(ret == -1){

1013

perror("close");

1514

1014

}

1515

1015

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

1532

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

1539

}

1540

1541

if(quit_now){

1542

goto end;

1543

}

1544

1545

ret = init_gnutls_global(pubkey, seckey);

1016

/* Restores kernel loglevel to default */

1017

ret = klogctl(7, NULL, 0);

1018

if(ret == -1){

1019

perror("klogctl");

1020

}

1021

#endif

1022

}

1023

1024

uid = getuid();

1025

gid = getgid();

1026

1027

setgid(gid);

1028

if(ret == -1){

1029

perror("setgid");

1030

}

1031

1032

ret = setuid(uid);

1033

if(ret == -1){

1034

perror("setuid");

1035

}

1036

1037

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

1546

1038

if(ret == -1){

1547

1039

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

1548

exitcode = EX_UNAVAILABLE;

1040

exitcode = EXIT_FAILURE;

1549

1041

goto end;

1550

1042

} else {

1551

1043

gnutls_initialized = true;

1552

1044

}

1553

1045

1554

if(quit_now){

1555

goto end;

1556

}

1557

1558

tempdir_created = true;

1559

1046

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

1047

perror("mkdtemp");

1562

1048

goto end;

1563

1049

}

1564

1565

if(quit_now){

1566

goto end;

1567

}

1568

1569

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

1050

tempdir_created = true;

1051

1052

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

1570

1053

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

1571

exitcode = EX_UNAVAILABLE;

1054

exitcode = EXIT_FAILURE;

1572

1055

goto end;

1573

1056

} else {

1574

1057

gpgme_initialized = true;

1575

1058

}

1576

1059

1577

if(quit_now){

1060

if_index = (AvahiIfIndex) if_nametoindex(interface);

1061

if(if_index == 0){

1062

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

1063

exitcode = EXIT_FAILURE;

1578

1064

goto end;

1579

1065

}

1580

1066

1584

1070

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

1585

1071

if(address == NULL){

1586

1072

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

1587

exitcode = EX_USAGE;

1588

goto end;

1589

}

1590

1591

if(quit_now){

1592

goto end;

1593

}

1594

1073

exitcode = EXIT_FAILURE;

1074

goto end;

1075

}

1595

1076

uint16_t port;

1596

errno = 0;

1597

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

1598

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

1599

or tmpmax != (uint16_t)tmpmax){

1077

ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);

1078

if(ret < 1 or tmpmax != (uint16_t)tmpmax

1079

or address[numchars+1] != '\0'){

1600

1080

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

1601

exitcode = EX_USAGE;

1602

goto end;

1603

}

1604

1605

if(quit_now){

1606

goto end;

1607

}

1608

1081

exitcode = EXIT_FAILURE;

1082

goto end;

1083

}

1609

1084

port = (uint16_t)tmpmax;

1610

1085

*address = '\0';

1611

1086

address = connect_to;

1612

/* Colon in address indicates IPv6 */

1613

int af;

1614

if(strchr(address, ':') != NULL){

1615

af = AF_INET6;

1087

ret = start_mandos_communication(address, port, if_index, &mc);

1088

if(ret < 0){

1089

exitcode = EXIT_FAILURE;

1616

1090

} else {

1617

af = AF_INET;

1618

}

1619

1620

if(quit_now){

1621

goto end;

1622

}

1623

1624

while(not quit_now){

1625

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

1626

if(quit_now or ret == 0){

1627

break;

1628

}

1629

sleep(15);

1630

};

1631

1632

if (not quit_now){

1633

1091

exitcode = EXIT_SUCCESS;

1634

1092

}

1635

1636

1093

goto end;

1637

1094

}

1638

1095

1639

if(quit_now){

1096

if(not debug){

1097

avahi_set_log_function(empty_log);

1098

}

1099

1100

/* Initialize the pseudo-RNG for Avahi */

1101

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

1102

1103

/* Allocate main Avahi loop object */

1104

mc.simple_poll = avahi_simple_poll_new();

1105

if(mc.simple_poll == NULL){

1106

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

1107

exitcode = EXIT_FAILURE;

1640

1108

goto end;

1641

1109

}

1642

1110

1662

1130

if(mc.server == NULL){

1663

1131

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

1664

1132

avahi_strerror(error));

1665

exitcode = EX_UNAVAILABLE;

1666

goto end;

1667

}

1668

1669

if(quit_now){

1133

exitcode = EXIT_FAILURE;

1670

1134

goto end;

1671

1135

}

1672

1136

1673

1137

/* Create the Avahi service browser */

1674

1138

sb = avahi_s_service_browser_new(mc.server, if_index,

1675

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

NULL, 0, browse_callback, NULL);

1139

AVAHI_PROTO_INET6, "_mandos._tcp",

1140

NULL, 0, browse_callback, &mc);

1677

1141

if(sb == NULL){

1678

1142

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

1679

1143

avahi_strerror(avahi_server_errno(mc.server)));

1680

exitcode = EX_UNAVAILABLE;

1681

goto end;

1682

}

1683

1684

if(quit_now){

1144

exitcode = EXIT_FAILURE;

1685

1145

goto end;

1686

1146

}

1687

1147

1719

1179

gpgme_release(mc.ctx);

1720

1180

}

1721

1181

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

1729

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1739

}

1740

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

1750

}

1751

}

1752

}

1753

1754

1182

/* Removes the temp directory used by GPGME */

1755

1183

if(tempdir_created){

1756

1184

DIR *d;

1795

1223

}

1796

1224

}

1797

1225

1798

if(quit_now){

1799

sigemptyset(&old_sigterm_action.sa_mask);

1800

old_sigterm_action.sa_handler = SIG_DFL;

1801

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1802

&old_sigterm_action,

1803

NULL));

1804

if(ret == -1){

1805

perror("sigaction");

1806

}

1807

do {

1808

ret = raise(signal_received);

1809

} while(ret != 0 and errno == EINTR);

1810

if(ret != 0){

1811

perror("raise");

1812

abort();

1813

}

1814

TEMP_FAILURE_RETRY(pause());

1815

}

1816

1817

1226

return exitcode;

1818

1227

}