/mandos/trunk : revision 181

32

#define _LARGEFILE_SOURCE

33

#define _FILE_OFFSET_BITS 64

34

35

#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */

35

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

36

37

#include <stdio.h>

38

#include <assert.h>

39

#include <stdlib.h>

40

#include <time.h>

41

#include <net/if.h> /* if_nametoindex */

42

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

43

SIOCSIFFLAGS */

37

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

38

stdout, ferror() */

39

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

40

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

41

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

42

srand() */

43

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

44

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

45

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

46

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

47

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

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sockaddr_in6, PF_INET6,

49

SOCK_STREAM, INET6_ADDRSTRLEN,

50

uid_t, gid_t, open(), opendir(), DIR */

51

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

52

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

53

struct in6_addr, inet_pton(),

54

connect() */

55

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

56

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

57

#include <inttypes.h> /* PRIu16 */

58

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

59

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

60

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

44

61

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

45

SIOCSIFFLAGS */

62

SIOCSIFFLAGS, if_indextoname(),

63

if_nametoindex(), IF_NAMESIZE */

64

#include <netinet/in.h>

65

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

66

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

67

setgid() */

68

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

69

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

70

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

71

argp_state, struct argp,

72

argp_parse(), ARGP_KEY_ARG,

73

ARGP_KEY_END, ARGP_ERR_UNKNOWN */

46

74

75

/* Avahi */

76

/* All Avahi types, constants and functions

77

Avahi*, avahi_*,

78

AVAHI_* */

47

79

#include <avahi-core/core.h>

48

80

#include <avahi-core/lookup.h>

49

81

#include <avahi-core/log.h>

51

83

#include <avahi-common/malloc.h>

52

84

#include <avahi-common/error.h>

53

85

54

/* Mandos client part */

55

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

56

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

57

struct in6_addr, inet_pton() */

58

#include <gnutls/gnutls.h> /* All GnuTLS stuff */

59

#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */

86

/* GnuTLS */

87

#include <gnutls/gnutls.h> /* All GnuTLS types, constants and

88

functions:

89

gnutls_*

90

init_gnutls_session(),

91

GNUTLS_* */

92

#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),

93

GNUTLS_OPENPGP_FMT_BASE64 */

60

94

61

#include <unistd.h> /* close() */

62

#include <netinet/in.h>

63

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

64

#include <string.h> /* memset */

65

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

66

#include <iso646.h> /* not */

67

#include <net/if.h> /* IF_NAMESIZE */

68

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

69

struct argp_state, struct argp,

70

argp_parse() */

71

95

/* GPGME */

72

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

73

#include <gpgme.h>

96

#include <gpgme.h> /* All GPGME types, constants and

97

functions:

98

gpgme_*

99

GPGME_PROTOCOL_OpenPGP,

100

GPG_ERR_NO_* */

74

101

75

102

#define BUFFER_SIZE 256

76

103

104

/*

105

#define PATHDIR "/conf/conf.d/mandos"

106

*/

107

108

#define PATHDIR "/conf/conf.d/mandos"

109

#define SECKEY "seckey.txt"

110

#define PUBKEY "pubkey.txt"

111

77

112

bool debug = false;

78

const char *keydir = "/conf/conf.d/mandos";

79

const char *argp_program_version = "mandosclient 0.9";

113

static const char mandos_protocol_version[] = "1";

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const char *argp_program_version = "mandos-client 1.0";

80

115

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

81

const char mandos_protocol_version[] = "1";

82

116

83

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

117

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

84

118

typedef struct {

85

119

AvahiSimplePoll *simple_poll;

86

120

AvahiServer *server;

88

122

unsigned int dh_bits;

89

123

gnutls_dh_params_t dh_params;

90

124

const char *priority;

125

gpgme_ctx_t ctx;

91

126

} mandos_context;

92

127

128

/*

129

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

130

* "buffer_capacity" is how much is currently allocated,

131

* "buffer_length" is how much is already used.

132

*/

93

133

size_t adjustbuffer(char **buffer, size_t buffer_length,

94

134

size_t buffer_capacity){

95

135

if (buffer_length + BUFFER_SIZE > buffer_capacity){

103

143

}

104

144

105

145

/*

106

* Decrypt OpenPGP data using keyrings in HOMEDIR.

107

* Returns -1 on error

146

* Initialize GPGME.

108

147

*/

109

static ssize_t pgp_packet_decrypt (const char *cryptotext,

110

size_t crypto_size,

111

char **plaintext,

112

const char *homedir){

113

gpgme_data_t dh_crypto, dh_plain;

114

gpgme_ctx_t ctx;

148

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

149

const char *pubkey, const char *tempdir){

150

int ret;

115

151

gpgme_error_t rc;

116

ssize_t ret;

117

size_t plaintext_capacity = 0;

118

ssize_t plaintext_length = 0;

119

152

gpgme_engine_info_t engine_info;

120

153

154

155

/*

156

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

157

*/

158

bool import_key(const char *filename){

159

int fd;

160

gpgme_data_t pgp_data;

161

162

fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

163

if(fd == -1){

164

perror("open");

165

return false;

166

}

167

168

rc = gpgme_data_new_from_fd(&pgp_data, fd);

169

if (rc != GPG_ERR_NO_ERROR){

170

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

171

gpgme_strsource(rc), gpgme_strerror(rc));

172

return false;

173

}

174

175

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

176

if (rc != GPG_ERR_NO_ERROR){

177

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

178

gpgme_strsource(rc), gpgme_strerror(rc));

179

return false;

180

}

181

182

ret = TEMP_FAILURE_RETRY(close(fd));

183

if(ret == -1){

184

perror("close");

185

}

186

gpgme_data_release(pgp_data);

187

return true;

188

}

189

121

190

if (debug){

122

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

191

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

123

192

}

124

193

125

194

/* Init GPGME */

128

197

if (rc != GPG_ERR_NO_ERROR){

129

198

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

130

199

gpgme_strsource(rc), gpgme_strerror(rc));

131

return -1;

200

return false;

132

201

}

133

202

134

/* Set GPGME home directory for the OpenPGP engine only */

203

/* Set GPGME home directory for the OpenPGP engine only */

135

204

rc = gpgme_get_engine_info (&engine_info);

136

205

if (rc != GPG_ERR_NO_ERROR){

137

206

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

138

207

gpgme_strsource(rc), gpgme_strerror(rc));

139

return -1;

208

return false;

140

209

}

141

210

while(engine_info != NULL){

142

211

if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){

143

212

gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,

144

engine_info->file_name, homedir);

213

engine_info->file_name, tempdir);

145

214

break;

146

215

}

147

216

engine_info = engine_info->next;

148

217

}

149

218

if(engine_info == NULL){

150

fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);

151

return -1;

219

fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);

220

return false;

221

}

222

223

/* Create new GPGME "context" */

224

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

225

if (rc != GPG_ERR_NO_ERROR){

226

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

227

gpgme_strsource(rc), gpgme_strerror(rc));

228

return false;

229

}

230

231

if (not import_key(pubkey) or not import_key(seckey)){

232

return false;

233

}

234

235

return true;

236

}

237

238

/*

239

* Decrypt OpenPGP data.

240

* Returns -1 on error

241

*/

242

static ssize_t pgp_packet_decrypt (const mandos_context *mc,

243

const char *cryptotext,

244

size_t crypto_size,

245

char **plaintext){

246

gpgme_data_t dh_crypto, dh_plain;

247

gpgme_error_t rc;

248

ssize_t ret;

249

size_t plaintext_capacity = 0;

250

ssize_t plaintext_length = 0;

251

252

if (debug){

253

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

152

254

}

153

255

154

256

/* Create new GPGME data buffer from memory cryptotext */

169

271

return -1;

170

272

}

171

273

172

/* Create new GPGME "context" */

173

rc = gpgme_new(&ctx);

174

if (rc != GPG_ERR_NO_ERROR){

175

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

176

gpgme_strsource(rc), gpgme_strerror(rc));

177

plaintext_length = -1;

178

goto decrypt_end;

179

}

180

181

274

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

182

275

data buffer */

183

rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);

276

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

184

277

if (rc != GPG_ERR_NO_ERROR){

185

278

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

186

279

gpgme_strsource(rc), gpgme_strerror(rc));

187

280

plaintext_length = -1;

281

if (debug){

282

gpgme_decrypt_result_t result;

283

result = gpgme_op_decrypt_result(mc->ctx);

284

if (result == NULL){

285

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

286

} else {

287

fprintf(stderr, "Unsupported algorithm: %s\n",

288

result->unsupported_algorithm);

289

fprintf(stderr, "Wrong key usage: %u\n",

290

result->wrong_key_usage);

291

if(result->file_name != NULL){

292

fprintf(stderr, "File name: %s\n", result->file_name);

293

}

294

gpgme_recipient_t recipient;

295

recipient = result->recipients;

296

if(recipient){

297

while(recipient != NULL){

298

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

299

gpgme_pubkey_algo_name(recipient->pubkey_algo));

300

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

301

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

302

recipient->status == GPG_ERR_NO_SECKEY

303

? "No" : "Yes");

304

recipient = recipient->next;

305

}

306

}

307

}

308

}

188

309

goto decrypt_end;

189

310

}

190

311

192

313

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

193

314

}

194

315

195

if (debug){

196

gpgme_decrypt_result_t result;

197

result = gpgme_op_decrypt_result(ctx);

198

if (result == NULL){

199

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

200

} else {

201

fprintf(stderr, "Unsupported algorithm: %s\n",

202

result->unsupported_algorithm);

203

fprintf(stderr, "Wrong key usage: %d\n",

204

result->wrong_key_usage);

205

if(result->file_name != NULL){

206

fprintf(stderr, "File name: %s\n", result->file_name);

207

}

208

gpgme_recipient_t recipient;

209

recipient = result->recipients;

210

if(recipient){

211

while(recipient != NULL){

212

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

213

gpgme_pubkey_algo_name(recipient->pubkey_algo));

214

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

215

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

216

recipient->status == GPG_ERR_NO_SECKEY

217

? "No" : "Yes");

218

recipient = recipient->next;

219

}

220

}

221

}

222

}

223

224

316

/* Seek back to the beginning of the GPGME plaintext data buffer */

225

317

if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){

226

perror("pgpme_data_seek");

318

perror("gpgme_data_seek");

227

319

plaintext_length = -1;

228

320

goto decrypt_end;

229

321

}

230

322

231

323

*plaintext = NULL;

232

324

while(true){

233

plaintext_capacity = adjustbuffer(plaintext, (size_t)plaintext_length,

325

plaintext_capacity = adjustbuffer(plaintext,

326

(size_t)plaintext_length,

234

327

plaintext_capacity);

235

328

if (plaintext_capacity == 0){

236

329

perror("adjustbuffer");

252

345

}

253

346

plaintext_length += ret;

254

347

}

255

348

256

349

if(debug){

257

350

fprintf(stderr, "Decrypted password is: ");

258

351

for(ssize_t i = 0; i < plaintext_length; i++){

272

365

}

273

366

274

367

static const char * safer_gnutls_strerror (int value) {

275

const char *ret = gnutls_strerror (value);

368

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

276

369

if (ret == NULL)

277

370

ret = "(unknown)";

278

371

return ret;

285

378

}

286

379

287

380

static int init_gnutls_global(mandos_context *mc,

288

const char *pubkeyfile,

289

const char *seckeyfile){

381

const char *pubkeyfilename,

382

const char *seckeyfilename){

290

383

int ret;

291

384

292

385

if(debug){

293

386

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

294

387

}

295

296

if ((ret = gnutls_global_init ())

297

!= GNUTLS_E_SUCCESS) {

388

389

ret = gnutls_global_init();

390

if (ret != GNUTLS_E_SUCCESS) {

298

391

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

299

392

safer_gnutls_strerror(ret));

300

393

return -1;

309

402

}

310

403

311

404

/* OpenPGP credentials */

312

if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))

313

!= GNUTLS_E_SUCCESS) {

314

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

405

gnutls_certificate_allocate_credentials(&mc->cred);

406

if (ret != GNUTLS_E_SUCCESS){

407

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

408

warning */

315

409

safer_gnutls_strerror(ret));

410

gnutls_global_deinit ();

316

411

return -1;

317

412

}

318

413

319

414

if(debug){

320

fprintf(stderr, "Attempting to use OpenPGP certificate %s"

321

" and keyfile %s as GnuTLS credentials\n", pubkeyfile,

322

seckeyfile);

415

fprintf(stderr, "Attempting to use OpenPGP public key %s and"

416

" secret key %s as GnuTLS credentials\n", pubkeyfilename,

417

seckeyfilename);

323

418

}

324

419

325

420

ret = gnutls_certificate_set_openpgp_key_file

326

(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);

421

(mc->cred, pubkeyfilename, seckeyfilename,

422

GNUTLS_OPENPGP_FMT_BASE64);

327

423

if (ret != GNUTLS_E_SUCCESS) {

328

424

fprintf(stderr,

329

425

"Error[%d] while reading the OpenPGP key pair ('%s',"

330

" '%s')\n", ret, pubkeyfile, seckeyfile);

331

fprintf(stdout, "The GnuTLS error is: %s\n",

426

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

427

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

332

428

safer_gnutls_strerror(ret));

333

return -1;

429

goto globalfail;

334

430

}

335

431

336

432

/* GnuTLS server initialization */

338

434

if (ret != GNUTLS_E_SUCCESS) {

339

435

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

340

436

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

341

return -1;

437

goto globalfail;

342

438

}

343

439

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

344

440

if (ret != GNUTLS_E_SUCCESS) {

345

441

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

346

442

safer_gnutls_strerror(ret));

347

return -1;

443

goto globalfail;

348

444

}

349

445

350

446

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

351

447

352

448

return 0;

449

450

globalfail:

451

452

gnutls_certificate_free_credentials(mc->cred);

453

gnutls_global_deinit();

454

gnutls_dh_params_deinit(mc->dh_params);

455

return -1;

353

456

}

354

457

355

static int init_gnutls_session(mandos_context *mc, gnutls_session_t *session){

458

static int init_gnutls_session(mandos_context *mc,

459

gnutls_session_t *session){

356

460

int ret;

357

461

/* GnuTLS session creation */

358

462

ret = gnutls_init(session, GNUTLS_SERVER);

368

472

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

369

473

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

370

474

safer_gnutls_strerror(ret));

475

gnutls_deinit (*session);

371

476

return -1;

372

477

}

373

478

}

377

482

if (ret != GNUTLS_E_SUCCESS) {

378

483

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

379

484

safer_gnutls_strerror(ret));

485

gnutls_deinit (*session);

380

486

return -1;

381

487

}

382

488

398

504

AvahiIfIndex if_index,

399

505

mandos_context *mc){

400

506

int ret, tcp_sd;

401

struct sockaddr_in6 to;

507

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

402

508

char *buffer = NULL;

403

509

char *decrypted_buffer;

404

510

size_t buffer_length = 0;

408

514

int retval = 0;

409

515

char interface[IF_NAMESIZE];

410

516

gnutls_session_t session;

411

gnutls_dh_params_t dh_params;

412

517

413

518

ret = init_gnutls_session (mc, &session);

414

519

if (ret != 0){

416

521

}

417

522

418

523

if(debug){

419

fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",

420

ip, port);

524

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

525

"\n", ip, port);

421

526

}

422

527

423

528

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

425

530

perror("socket");

426

531

return -1;

427

532

}

428

533

429

534

if(debug){

430

535

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

431

536

perror("if_indextoname");

434

539

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

435

540

}

436

541

437

memset(&to,0,sizeof(to)); /* Spurious warning */

438

to.sin6_family = AF_INET6;

542

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

543

to.in6.sin6_family = AF_INET6;

439

544

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

440

545

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

441

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

546

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

442

547

if (ret < 0 ){

443

548

perror("inet_pton");

444

549

return -1;

447

552

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

448

553

return -1;

449

554

}

450

to.sin6_port = htons(port); /* Spurious warning */

555

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

451

556

452

to.sin6_scope_id = (uint32_t)if_index;

557

to.in6.sin6_scope_id = (uint32_t)if_index;

453

558

454

559

if(debug){

455

fprintf(stderr, "Connection to: %s, port %d\n", ip, port);

560

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

561

port);

456

562

char addrstr[INET6_ADDRSTRLEN] = "";

457

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

563

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

458

564

sizeof(addrstr)) == NULL){

459

565

perror("inet_ntop");

460

566

} else {

464

570

}

465

571

}

466

572

467

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

573

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

468

574

if (ret < 0){

469

575

perror("connect");

470

576

return -1;

471

577

}

472

578

473

579

const char *out = mandos_protocol_version;

474

580

written = 0;

475

581

while (true){

493

599

}

494

600

}

495

601

}

496

602

497

603

if(debug){

498

604

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

499

605

}

500

606

501

607

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

502

608

503

ret = gnutls_handshake (session);

609

do{

610

ret = gnutls_handshake (session);

611

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

504

612

505

613

if (ret != GNUTLS_E_SUCCESS){

506

614

if(debug){

517

625

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

518

626

ip);

519

627

}

520

628

521

629

while(true){

522

buffer_capacity = adjustbuffer(&buffer, buffer_length, buffer_capacity);

630

buffer_capacity = adjustbuffer(&buffer, buffer_length,

631

buffer_capacity);

523

632

if (buffer_capacity == 0){

524

633

perror("adjustbuffer");

525

634

retval = -1;

537

646

case GNUTLS_E_AGAIN:

538

647

break;

539

648

case GNUTLS_E_REHANDSHAKE:

540

ret = gnutls_handshake (session);

649

do{

650

ret = gnutls_handshake (session);

651

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

541

652

if (ret < 0){

542

653

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

543

654

gnutls_perror (ret);

564

675

gnutls_bye (session, GNUTLS_SHUT_RDWR);

565

676

566

677

if (buffer_length > 0){

567

decrypted_buffer_size = pgp_packet_decrypt(buffer,

678

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

568

679

buffer_length,

569

&decrypted_buffer,

570

keydir);

680

&decrypted_buffer);

571

681

if (decrypted_buffer_size >= 0){

572

682

written = 0;

573

683

while(written < (size_t) decrypted_buffer_size){

588

698

} else {

589

699

retval = -1;

590

700

}

701

} else {

702

retval = -1;

591

703

}

592

704

593

705

/* Shutdown procedure */

594

706

595

707

mandos_end:

596

708

free(buffer);

597

close(tcp_sd);

709

ret = TEMP_FAILURE_RETRY(close(tcp_sd));

710

if(ret == -1){

711

perror("close");

712

}

598

713

gnutls_deinit (session);

599

gnutls_certificate_free_credentials (mc->cred);

600

gnutls_global_deinit ();

601

714

return retval;

602

715

}

603

716

616

729

flags,

617

730

void* userdata) {

618

731

mandos_context *mc = userdata;

619

assert(r); /* Spurious warning */

732

assert(r);

620

733

621

734

/* Called whenever a service has been resolved successfully or

622

735

timed out */

634

747

char ip[AVAHI_ADDRESS_STR_MAX];

635

748

avahi_address_snprint(ip, sizeof(ip), address);

636

749

if(debug){

637

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"

638

" port %d\n", name, host_name, ip, interface, port);

750

fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"

751

PRIu16 ") on port %d\n", name, host_name, ip,

752

interface, port);

639

753

}

640

754

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

641

755

if (ret == 0){

642

exit(EXIT_SUCCESS);

756

avahi_simple_poll_quit(mc->simple_poll);

643

757

}

644

758

}

645

759

}

657

771

flags,

658

772

void* userdata) {

659

773

mandos_context *mc = userdata;

660

assert(b); /* Spurious warning */

774

assert(b);

661

775

662

776

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

663

777

is removed from the LAN */

697

811

}

698

812

}

699

813

700

/* Combines file name and path and returns the malloced new

701

string. some sane checks could/should be added */

702

static const char *combinepath(const char *first, const char *second){

703

size_t f_len = strlen(first);

704

size_t s_len = strlen(second);

705

char *tmp = malloc(f_len + s_len + 2);

706

if (tmp == NULL){

707

return NULL;

708

}

709

if(f_len > 0){

710

memcpy(tmp, first, f_len); /* Spurious warning */

711

}

712

tmp[f_len] = '/';

713

if(s_len > 0){

714

memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */

715

}

716

tmp[f_len + 1 + s_len] = '\0';

717

return tmp;

718

}

719

720

721

814

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

722

815

AvahiSServiceBrowser *sb = NULL;

723

816

int error;

729

822

uid_t uid;

730

823

gid_t gid;

731

824

char *connect_to = NULL;

825

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

732

826

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

733

const char *pubkeyfile = "pubkey.txt";

734

const char *seckeyfile = "seckey.txt";

827

const char *seckey = PATHDIR "/" SECKEY;

828

const char *pubkey = PATHDIR "/" PUBKEY;

829

735

830

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

736

.dh_bits = 1024, .priority = "SECURE256"};

831

.dh_bits = 1024, .priority = "SECURE256"

832

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

833

bool gnutls_initalized = false;

834

bool gpgme_initalized = false;

737

835

738

836

{

739

837

struct argp_option options[] = {

740

838

{ .name = "debug", .key = 128,

741

839

.doc = "Debug mode", .group = 3 },

742

840

{ .name = "connect", .key = 'c',

743

.arg = "IP",

744

.doc = "Connect directly to a sepcified mandos server", .group = 1 },

841

.arg = "ADDRESS:PORT",

842

.doc = "Connect directly to a specific Mandos server",

843

.group = 1 },

745

844

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

746

.arg = "INTERFACE",

747

.doc = "Interface that Avahi will conntect through", .group = 1 },

748

{ .name = "keydir", .key = 'd',

749

.arg = "KEYDIR",

750

.doc = "Directory where the openpgp keyring is", .group = 1 },

845

.arg = "NAME",

846

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

847

" servers",

848

.group = 1 },

751

849

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

752

.arg = "SECKEY",

753

.doc = "Secret openpgp key for gnutls authentication", .group = 1 },

850

.arg = "FILE",

851

.doc = "OpenPGP secret key file base name",

852

.group = 1 },

754

853

{ .name = "pubkey", .key = 'p',

755

.arg = "PUBKEY",

756

.doc = "Public openpgp key for gnutls authentication", .group = 2 },

854

.arg = "FILE",

855

.doc = "OpenPGP public key file base name",

856

.group = 2 },

757

857

{ .name = "dh-bits", .key = 129,

758

858

.arg = "BITS",

759

.doc = "dh-bits to use in gnutls communication", .group = 2 },

859

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

860

" Diffie-Hellman key exchange",

861

.group = 2 },

760

862

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

761

.arg = "PRIORITY",

762

.doc = "GNUTLS priority", .group = 1 },

863

.arg = "STRING",

864

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

865

.group = 1 },

763

866

{ .name = NULL }

764

867

};

765

766

868

767

error_t parse_opt (int key, char *arg, struct argp_state *state) {

768

/* Get the INPUT argument from `argp_parse', which we know is a

769

pointer to our plugin list pointer. */

869

error_t parse_opt (int key, char *arg,

870

struct argp_state *state) {

871

/* Get the INPUT argument from `argp_parse', which we know is

872

a pointer to our plugin list pointer. */

770

873

switch (key) {

771

case 128:

874

case 128: /* --debug */

772

875

debug = true;

773

876

break;

774

case 'c':

877

case 'c': /* --connect */

775

878

connect_to = arg;

776

879

break;

777

case 'i':

880

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

778

881

interface = arg;

779

882

break;

780

case 'd':

781

keydir = arg;

782

break;

783

case 's':

784

seckeyfile = arg;

785

break;

786

case 'p':

787

pubkeyfile = arg;

788

break;

789

case 129:

883

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

884

seckey = arg;

885

break;

886

case 'p': /* --pubkey */

887

pubkey = arg;

888

break;

889

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

790

890

errno = 0;

791

891

mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);

792

892

if (errno){

794

894

exit(EXIT_FAILURE);

795

895

}

796

896

break;

797

case 130:

897

case 130: /* --priority */

798

898

mc.priority = arg;

799

899

break;

800

900

case ARGP_KEY_ARG:

801

901

argp_usage (state);

902

case ARGP_KEY_END:

802

903

break;

803

case ARGP_KEY_END:

804

break;

805

904

default:

806

905

return ARGP_ERR_UNKNOWN;

807

906

}

808

907

return 0;

809

908

}

810

909

811

910

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

812

911

.args_doc = "",

813

.doc = "Mandos client -- Get and decrypt passwords from mandos server" };

814

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

815

}

816

817

pubkeyfile = combinepath(keydir, pubkeyfile);

818

if (pubkeyfile == NULL){

819

perror("combinepath");

820

exitcode = EXIT_FAILURE;

821

goto end;

822

}

823

824

seckeyfile = combinepath(keydir, seckeyfile);

825

if (seckeyfile == NULL){

826

perror("combinepath");

827

goto end;

828

}

829

830

ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);

831

if (ret == -1){

832

fprintf(stderr, "init_gnutls_global\n");

833

goto end;

834

}

835

912

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

913

" passwords from a Mandos server" };

914

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

915

if (ret == ARGP_ERR_UNKNOWN){

916

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

917

exitcode = EXIT_FAILURE;

918

goto end;

919

}

920

}

921

922

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

923

{

924

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

925

if(sd < 0) {

926

perror("socket");

927

exitcode = EXIT_FAILURE;

928

goto end;

929

}

930

strcpy(network.ifr_name, interface);

931

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

932

if(ret == -1){

933

perror("ioctl SIOCGIFFLAGS");

934

exitcode = EXIT_FAILURE;

935

goto end;

936

}

937

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

938

network.ifr_flags |= IFF_UP;

939

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

940

if(ret == -1){

941

perror("ioctl SIOCSIFFLAGS");

942

exitcode = EXIT_FAILURE;

943

goto end;

944

}

945

}

946

ret = TEMP_FAILURE_RETRY(close(sd));

947

if(ret == -1){

948

perror("close");

949

}

950

}

951

836

952

uid = getuid();

837

953

gid = getgid();

838

954

839

955

ret = setuid(uid);

840

956

if (ret == -1){

841

957

perror("setuid");

846

962

perror("setgid");

847

963

}

848

964

965

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

966

if (ret == -1){

967

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

968

exitcode = EXIT_FAILURE;

969

goto end;

970

} else {

971

gnutls_initalized = true;

972

}

973

974

if(mkdtemp(tempdir) == NULL){

975

perror("mkdtemp");

976

tempdir[0] = '\0';

977

goto end;

978

}

979

980

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

981

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

982

exitcode = EXIT_FAILURE;

983

goto end;

984

} else {

985

gpgme_initalized = true;

986

}

987

849

988

if_index = (AvahiIfIndex) if_nametoindex(interface);

850

989

if(if_index == 0){

851

990

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

879

1018

goto end;

880

1019

}

881

1020

882

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

883

{

884

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

885

if(sd < 0) {

886

perror("socket");

887

exitcode = EXIT_FAILURE;

888

goto end;

889

}

890

strcpy(network.ifr_name, interface); /* Spurious warning */

891

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

892

if(ret == -1){

893

perror("ioctl SIOCGIFFLAGS");

894

exitcode = EXIT_FAILURE;

895

goto end;

896

}

897

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

898

network.ifr_flags |= IFF_UP;

899

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

900

if(ret == -1){

901

perror("ioctl SIOCSIFFLAGS");

902

exitcode = EXIT_FAILURE;

903

goto end;

904

}

905

}

906

close(sd);

907

}

908

909

1021

if (not debug){

910

1022

avahi_set_log_function(empty_log);

911

1023

}

921

1033

exitcode = EXIT_FAILURE;

922

1034

goto end;

923

1035

}

924

1036

925

1037

{

926

1038

AvahiServerConfig config;

927

1039

/* Do not publish any local Zeroconf records */

930

1042

config.publish_addresses = 0;

931

1043

config.publish_workstation = 0;

932

1044

config.publish_domain = 0;

933

1045

934

1046

/* Allocate a new server */

935

1047

mc.server = avahi_server_new(avahi_simple_poll_get

936

1048

(mc.simple_poll), &config, NULL,

937

1049

NULL, &error);

938

1050

939

1051

/* Free the Avahi configuration data */

940

1052

avahi_server_config_free(&config);

941

1053

}

961

1073

}

962

1074

963

1075

/* Run the main loop */

964

1076

965

1077

if (debug){

966

1078

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

967

1079

}

969

1081

avahi_simple_poll_loop(mc.simple_poll);

970

1082

971

1083

end:

972

1084

973

1085

if (debug){

974

1086

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

975

1087

}

980

1092

981

1093

if (mc.server != NULL)

982

1094

avahi_server_free(mc.server);

983

1095

984

1096

if (mc.simple_poll != NULL)

985

1097

avahi_simple_poll_free(mc.simple_poll);

986

free(pubkeyfile);

987

free(seckeyfile);

988

1098

1099

if (gnutls_initalized){

1100

gnutls_certificate_free_credentials(mc.cred);

1101

gnutls_global_deinit ();

1102

gnutls_dh_params_deinit(mc.dh_params);

1103

}

1104

1105

if(gpgme_initalized){

1106

gpgme_release(mc.ctx);

1107

}

1108

1109

/* Removes the temp directory used by GPGME */

1110

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

1111

DIR *d;

1112

struct dirent *direntry;

1113

d = opendir(tempdir);

1114

if(d == NULL){

1115

perror("opendir");

1116

} else {

1117

while(true){

1118

direntry = readdir(d);

1119

if(direntry == NULL){

1120

break;

1121

}

1122

if (direntry->d_type == DT_REG){

1123

char *fullname = NULL;

1124

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

1125

direntry->d_name);

1126

if(ret < 0){

1127

perror("asprintf");

1128

continue;

1129

}

1130

ret = unlink(fullname);

1131

if(ret == -1){

1132

fprintf(stderr, "unlink(\"%s\"): %s",

1133

fullname, strerror(errno));

1134

}

1135

free(fullname);

1136

}

1137

}

1138

closedir(d);

1139

}

1140

ret = rmdir(tempdir);

1141

if(ret == -1){

1142

perror("rmdir");

1143

}

1144

}

1145

989

1146

return exitcode;

990

1147

}