/mandos/trunk : revision 24.1.93

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,

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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,

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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 */

60

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 */

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 */

68

94

69

95

/* GPGME */

70

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

71

#include <gpgme.h>

72

73

/* getopt_long */

74

#include <getopt.h>

96

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

97

functions:

98

gpgme_*

99

GPGME_PROTOCOL_OpenPGP,

100

GPG_ERR_NO_* */

75

101

76

102

#define BUFFER_SIZE 256

77

103

78

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

79

static const char *pubkeyfile = "pubkey.txt";

80

static const char *seckeyfile = "seckey.txt";

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 "pupkey.txt"

81

111

82

112

bool debug = false;

83

84

const char mandos_protocol_version[] = "1";

85

86

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

113

static const char mandos_protocol_version[] = "1";

114

const char *argp_program_version = "password-request 1.0";

115

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

116

117

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

87

118

typedef struct {

88

119

AvahiSimplePoll *simple_poll;

89

120

AvahiServer *server;

91

122

unsigned int dh_bits;

92

123

gnutls_dh_params_t dh_params;

93

124

const char *priority;

125

gpgme_ctx_t ctx;

94

126

} mandos_context;

95

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

*/

96

133

size_t adjustbuffer(char **buffer, size_t buffer_length,

97

134

size_t buffer_capacity){

98

135

if (buffer_length + BUFFER_SIZE > buffer_capacity){

106

143

}

107

144

108

145

/*

109

* Decrypt OpenPGP data using keyrings in HOMEDIR.

110

* Returns -1 on error

146

* Initialize GPGME.

111

147

*/

112

static ssize_t pgp_packet_decrypt (const char *cryptotext,

113

size_t crypto_size,

114

char **plaintext,

115

const char *homedir){

116

gpgme_data_t dh_crypto, dh_plain;

117

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;

118

151

gpgme_error_t rc;

119

ssize_t ret;

120

size_t plaintext_capacity = 0;

121

ssize_t plaintext_length = 0;

122

152

gpgme_engine_info_t engine_info;

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

}

123

189

124

190

if (debug){

125

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

191

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

126

192

}

127

193

128

194

/* Init GPGME */

129

195

gpgme_check_version(NULL);

130

196

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

131

197

if (rc != GPG_ERR_NO_ERROR){

132

198

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

133

199

gpgme_strsource(rc), gpgme_strerror(rc));

134

return -1;

200

return false;

135

201

}

136

137

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

202

203

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

138

204

rc = gpgme_get_engine_info (&engine_info);

139

205

if (rc != GPG_ERR_NO_ERROR){

140

206

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

141

207

gpgme_strsource(rc), gpgme_strerror(rc));

142

return -1;

208

return false;

143

209

}

144

210

while(engine_info != NULL){

145

211

if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){

146

212

gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,

147

engine_info->file_name, homedir);

213

engine_info->file_name, tempdir);

148

214

break;

149

215

}

150

216

engine_info = engine_info->next;

151

217

}

152

218

if(engine_info == NULL){

153

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

154

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");

155

254

}

156

255

157

256

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

172

271

return -1;

173

272

}

174

273

175

/* Create new GPGME "context" */

176

rc = gpgme_new(&ctx);

177

if (rc != GPG_ERR_NO_ERROR){

178

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

179

gpgme_strsource(rc), gpgme_strerror(rc));

180

plaintext_length = -1;

181

goto decrypt_end;

182

}

183

184

274

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

185

275

data buffer */

186

rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);

276

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

187

277

if (rc != GPG_ERR_NO_ERROR){

188

278

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

189

279

gpgme_strsource(rc), gpgme_strerror(rc));

190

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

}

191

309

goto decrypt_end;

192

310

}

193

311

195

313

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

196

314

}

197

315

198

if (debug){

199

gpgme_decrypt_result_t result;

200

result = gpgme_op_decrypt_result(ctx);

201

if (result == NULL){

202

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

203

} else {

204

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

205

result->unsupported_algorithm);

206

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

207

result->wrong_key_usage);

208

if(result->file_name != NULL){

209

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

210

}

211

gpgme_recipient_t recipient;

212

recipient = result->recipients;

213

if(recipient){

214

while(recipient != NULL){

215

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

216

gpgme_pubkey_algo_name(recipient->pubkey_algo));

217

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

218

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

219

recipient->status == GPG_ERR_NO_SECKEY

220

? "No" : "Yes");

221

recipient = recipient->next;

222

}

223

}

224

}

225

}

226

227

316

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

228

317

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

229

perror("pgpme_data_seek");

318

perror("gpgme_data_seek");

230

319

plaintext_length = -1;

231

320

goto decrypt_end;

232

321

}

233

322

234

323

*plaintext = NULL;

235

324

while(true){

236

plaintext_capacity = adjustbuffer(plaintext, (size_t)plaintext_length,

325

plaintext_capacity = adjustbuffer(plaintext,

326

(size_t)plaintext_length,

237

327

plaintext_capacity);

238

328

if (plaintext_capacity == 0){

239

329

perror("adjustbuffer");

255

345

}

256

346

plaintext_length += ret;

257

347

}

258

348

259

349

if(debug){

260

350

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

261

351

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

275

365

}

276

366

277

367

static const char * safer_gnutls_strerror (int value) {

278

const char *ret = gnutls_strerror (value);

368

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

279

369

if (ret == NULL)

280

370

ret = "(unknown)";

281

371

return ret;

287

377

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

288

378

}

289

379

290

static int init_gnutls_global(mandos_context *mc){

380

static int init_gnutls_global(mandos_context *mc,

381

const char *pubkeyfilename,

382

const char *seckeyfilename){

291

383

int ret;

292

384

293

385

if(debug){

294

386

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

295

387

}

296

297

if ((ret = gnutls_global_init ())

298

!= GNUTLS_E_SUCCESS) {

388

389

ret = gnutls_global_init();

390

if (ret != GNUTLS_E_SUCCESS) {

299

391

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

300

392

safer_gnutls_strerror(ret));

301

393

return -1;

310

402

}

311

403

312

404

/* OpenPGP credentials */

313

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

314

!= GNUTLS_E_SUCCESS) {

315

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 */

316

409

safer_gnutls_strerror(ret));

410

gnutls_global_deinit ();

317

411

return -1;

318

412

}

319

413

320

414

if(debug){

321

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

322

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

323

seckeyfile);

415

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

416

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

417

seckeyfilename);

324

418

}

325

419

326

420

ret = gnutls_certificate_set_openpgp_key_file

327

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

421

(mc->cred, pubkeyfilename, seckeyfilename,

422

GNUTLS_OPENPGP_FMT_BASE64);

328

423

if (ret != GNUTLS_E_SUCCESS) {

329

424

fprintf(stderr,

330

425

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

331

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

332

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

426

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

427

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

333

428

safer_gnutls_strerror(ret));

334

return -1;

429

goto globalfail;

335

430

}

336

431

337

432

/* GnuTLS server initialization */

339

434

if (ret != GNUTLS_E_SUCCESS) {

340

435

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

341

436

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

342

return -1;

437

goto globalfail;

343

438

}

344

439

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

345

440

if (ret != GNUTLS_E_SUCCESS) {

346

441

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

347

442

safer_gnutls_strerror(ret));

348

return -1;

443

goto globalfail;

349

444

}

350

445

351

446

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

352

447

353

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;

354

456

}

355

457

356

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){

357

460

int ret;

358

461

/* GnuTLS session creation */

359

462

ret = gnutls_init(session, GNUTLS_SERVER);

369

472

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

370

473

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

371

474

safer_gnutls_strerror(ret));

475

gnutls_deinit (*session);

372

476

return -1;

373

477

}

374

478

}

378

482

if (ret != GNUTLS_E_SUCCESS) {

379

483

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

380

484

safer_gnutls_strerror(ret));

485

gnutls_deinit (*session);

381

486

return -1;

382

487

}

383

488

399

504

AvahiIfIndex if_index,

400

505

mandos_context *mc){

401

506

int ret, tcp_sd;

402

struct sockaddr_in6 to;

507

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

403

508

char *buffer = NULL;

404

509

char *decrypted_buffer;

405

510

size_t buffer_length = 0;

409

514

int retval = 0;

410

515

char interface[IF_NAMESIZE];

411

516

gnutls_session_t session;

412

gnutls_dh_params_t dh_params;

413

517

414

518

ret = init_gnutls_session (mc, &session);

415

519

if (ret != 0){

417

521

}

418

522

419

523

if(debug){

420

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

421

ip, port);

524

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

525

"\n", ip, port);

422

526

}

423

527

424

528

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

426

530

perror("socket");

427

531

return -1;

428

532

}

429

533

430

534

if(debug){

431

535

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

432

536

perror("if_indextoname");

435

539

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

436

540

}

437

541

438

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

439

to.sin6_family = AF_INET6;

542

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

543

to.in6.sin6_family = AF_INET6;

440

544

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

441

545

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

442

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

546

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

443

547

if (ret < 0 ){

444

548

perror("inet_pton");

445

549

return -1;

448

552

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

449

553

return -1;

450

554

}

451

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

555

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

452

556

453

to.sin6_scope_id = (uint32_t)if_index;

557

to.in6.sin6_scope_id = (uint32_t)if_index;

454

558

455

559

if(debug){

456

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

560

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

561

port);

457

562

char addrstr[INET6_ADDRSTRLEN] = "";

458

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

563

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

459

564

sizeof(addrstr)) == NULL){

460

565

perror("inet_ntop");

461

566

} else {

465

570

}

466

571

}

467

572

468

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

573

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

469

574

if (ret < 0){

470

575

perror("connect");

471

576

return -1;

472

577

}

473

578

474

579

const char *out = mandos_protocol_version;

475

580

written = 0;

476

581

while (true){

494

599

}

495

600

}

496

601

}

497

602

498

603

if(debug){

499

604

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

500

605

}

501

606

502

607

gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);

503

608

504

ret = gnutls_handshake (session);

609

do{

610

ret = gnutls_handshake (session);

611

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

505

612

506

613

if (ret != GNUTLS_E_SUCCESS){

507

614

if(debug){

518

625

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

519

626

ip);

520

627

}

521

628

522

629

while(true){

523

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

630

buffer_capacity = adjustbuffer(&buffer, buffer_length,

631

buffer_capacity);

524

632

if (buffer_capacity == 0){

525

633

perror("adjustbuffer");

526

634

retval = -1;

538

646

case GNUTLS_E_AGAIN:

539

647

break;

540

648

case GNUTLS_E_REHANDSHAKE:

541

ret = gnutls_handshake (session);

649

do{

650

ret = gnutls_handshake (session);

651

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

542

652

if (ret < 0){

543

653

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

544

654

gnutls_perror (ret);

565

675

gnutls_bye (session, GNUTLS_SHUT_RDWR);

566

676

567

677

if (buffer_length > 0){

568

decrypted_buffer_size = pgp_packet_decrypt(buffer,

678

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

569

679

buffer_length,

570

&decrypted_buffer,

571

keydir);

680

&decrypted_buffer);

572

681

if (decrypted_buffer_size >= 0){

573

682

written = 0;

574

683

while(written < (size_t) decrypted_buffer_size){

589

698

} else {

590

699

retval = -1;

591

700

}

701

} else {

702

retval = -1;

592

703

}

593

704

594

705

/* Shutdown procedure */

595

706

596

707

mandos_end:

597

708

free(buffer);

598

close(tcp_sd);

709

ret = TEMP_FAILURE_RETRY(close(tcp_sd));

710

if(ret == -1){

711

perror("close");

712

}

599

713

gnutls_deinit (session);

600

gnutls_certificate_free_credentials (mc->cred);

601

gnutls_global_deinit ();

602

714

return retval;

603

715

}

604

716

617

729

flags,

618

730

void* userdata) {

619

731

mandos_context *mc = userdata;

620

assert(r); /* Spurious warning */

732

assert(r);

621

733

622

734

/* Called whenever a service has been resolved successfully or

623

735

timed out */

635

747

char ip[AVAHI_ADDRESS_STR_MAX];

636

748

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

637

749

if(debug){

638

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

639

" 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);

640

753

}

641

754

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

642

755

if (ret == 0){

643

exit(EXIT_SUCCESS);

756

avahi_simple_poll_quit(mc->simple_poll);

644

757

}

645

758

}

646

759

}

658

771

flags,

659

772

void* userdata) {

660

773

mandos_context *mc = userdata;

661

assert(b); /* Spurious warning */

774

assert(b);

662

775

663

776

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

664

777

is removed from the LAN */

698

811

}

699

812

}

700

813

701

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

702

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

703

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

704

size_t f_len = strlen(first);

705

size_t s_len = strlen(second);

706

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

707

if (tmp == NULL){

708

return NULL;

709

}

710

if(f_len > 0){

711

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

712

}

713

tmp[f_len] = '/';

714

if(s_len > 0){

715

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

716

}

717

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

718

return tmp;

719

}

720

721

722

814

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

723

815

AvahiSServiceBrowser *sb = NULL;

724

816

int error;

730

822

uid_t uid;

731

823

gid_t gid;

732

824

char *connect_to = NULL;

825

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

733

826

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

827

const char *seckey = PATHDIR "/" SECKEY;

828

const char *pubkey = PATHDIR "/" PUBKEY;

829

734

830

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

735

.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;

736

835

737

836

{

738

/* Temporary int to get the address of for getopt_long */

739

int debug_int = debug ? 1 : 0;

740

while (true){

741

struct option long_options[] = {

742

{"debug", no_argument, &debug_int, 1},

743

{"connect", required_argument, NULL, 'c'},

744

{"interface", required_argument, NULL, 'i'},

745

{"keydir", required_argument, NULL, 'd'},

746

{"seckey", required_argument, NULL, 's'},

747

{"pubkey", required_argument, NULL, 'p'},

748

{"dh-bits", required_argument, NULL, 'D'},

749

{"priority", required_argument, NULL, 'P'},

750

{0, 0, 0, 0} };

751

752

int option_index = 0;

753

ret = getopt_long (argc, argv, "i:", long_options,

754

&option_index);

755

756

if (ret == -1){

757

break;

758

}

759

760

switch(ret){

761

case 0:

762

break;

763

case 'i':

764

interface = optarg;

765

break;

766

case 'c':

767

connect_to = optarg;

768

break;

769

case 'd':

770

keydir = optarg;

771

break;

772

case 'p':

773

pubkeyfile = optarg;

774

break;

775

case 's':

776

seckeyfile = optarg;

777

break;

778

case 'D':

837

struct argp_option options[] = {

838

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

839

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

840

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

841

.arg = "ADDRESS:PORT",

842

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

843

.group = 1 },

844

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

845

.arg = "NAME",

846

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

847

" servers",

848

.group = 1 },

849

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

850

.arg = "FILE",

851

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

852

.group = 1 },

853

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

854

.arg = "FILE",

855

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

856

.group = 2 },

857

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

858

.arg = "BITS",

859

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

860

" Diffie-Hellman key exchange",

861

.group = 2 },

862

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

863

.arg = "STRING",

864

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

865

.group = 1 },

866

{ .name = NULL }

867

};

868

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. */

873

switch (key) {

874

case 128: /* --debug */

875

debug = true;

876

break;

877

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

878

connect_to = arg;

879

break;

880

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

881

interface = arg;

882

break;

883

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

884

seckey = arg;

885

break;

886

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

887

pubkey = arg;

888

break;

889

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

779

890

errno = 0;

780

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

891

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

781

892

if (errno){

782

893

perror("strtol");

783

894

exit(EXIT_FAILURE);

784

895

}

785

896

break;

786

case 'P':

787

mc.priority = optarg;

788

break;

789

case '?':

897

case 130: /* --priority */

898

mc.priority = arg;

899

break;

900

case ARGP_KEY_ARG:

901

argp_usage (state);

902

case ARGP_KEY_END:

903

break;

790

904

default:

791

/* getopt_long() has already printed a message about the

792

unrcognized option, so just exit. */

793

exit(EXIT_FAILURE);

905

return ARGP_ERR_UNKNOWN;

794

906

}

795

}

796

/* Set the global debug flag from the temporary int */

797

debug = debug_int ? true : false;

798

}

799

800

pubkeyfile = combinepath(keydir, pubkeyfile);

801

if (pubkeyfile == NULL){

802

perror("combinepath");

803

exitcode = EXIT_FAILURE;

804

goto end;

805

}

806

807

seckeyfile = combinepath(keydir, seckeyfile);

808

if (seckeyfile == NULL){

809

perror("combinepath");

810

goto end;

811

}

812

813

ret = init_gnutls_global(&mc);

907

return 0;

908

}

909

910

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

911

.args_doc = "",

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

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

814

923

if (ret == -1){

815

fprintf(stderr, "init_gnutls_global\n");

924

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

925

exitcode = EXIT_FAILURE;

816

926

goto end;

927

} else {

928

gnutls_initalized = true;

817

929

}

818

930

931

if(mkdtemp(tempdir) == NULL){

932

perror("mkdtemp");

933

tempdir[0] = '\0';

934

goto end;

935

}

936

937

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

938

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

939

exitcode = EXIT_FAILURE;

940

goto end;

941

} else {

942

gpgme_initalized = true;

943

}

944

945

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

946

{

947

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

948

if(sd < 0) {

949

perror("socket");

950

exitcode = EXIT_FAILURE;

951

goto end;

952

}

953

strcpy(network.ifr_name, interface);

954

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

955

if(ret == -1){

956

perror("ioctl SIOCGIFFLAGS");

957

exitcode = EXIT_FAILURE;

958

goto end;

959

}

960

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

961

network.ifr_flags |= IFF_UP;

962

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

963

if(ret == -1){

964

perror("ioctl SIOCSIFFLAGS");

965

exitcode = EXIT_FAILURE;

966

goto end;

967

}

968

}

969

ret = TEMP_FAILURE_RETRY(close(sd));

970

if(ret == -1){

971

perror("close");

972

}

973

}

974

819

975

uid = getuid();

820

976

gid = getgid();

821

977

822

978

ret = setuid(uid);

823

979

if (ret == -1){

824

980

perror("setuid");

862

1018

goto end;

863

1019

}

864

1020

865

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

866

{

867

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

868

if(sd < 0) {

869

perror("socket");

870

exitcode = EXIT_FAILURE;

871

goto end;

872

}

873

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

874

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

875

if(ret == -1){

876

perror("ioctl SIOCGIFFLAGS");

877

exitcode = EXIT_FAILURE;

878

goto end;

879

}

880

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

881

network.ifr_flags |= IFF_UP;

882

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

883

if(ret == -1){

884

perror("ioctl SIOCSIFFLAGS");

885

exitcode = EXIT_FAILURE;

886

goto end;

887

}

888

}

889

close(sd);

890

}

891

892

1021

if (not debug){

893

1022

avahi_set_log_function(empty_log);

894

1023

}

904

1033

exitcode = EXIT_FAILURE;

905

1034

goto end;

906

1035

}

907

1036

908

1037

{

909

1038

AvahiServerConfig config;

910

1039

/* Do not publish any local Zeroconf records */

913

1042

config.publish_addresses = 0;

914

1043

config.publish_workstation = 0;

915

1044

config.publish_domain = 0;

916

1045

917

1046

/* Allocate a new server */

918

1047

mc.server = avahi_server_new(avahi_simple_poll_get

919

1048

(mc.simple_poll), &config, NULL,

920

1049

NULL, &error);

921

1050

922

1051

/* Free the Avahi configuration data */

923

1052

avahi_server_config_free(&config);

924

1053

}

944

1073

}

945

1074

946

1075

/* Run the main loop */

947

1076

948

1077

if (debug){

949

1078

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

950

1079

}

952

1081

avahi_simple_poll_loop(mc.simple_poll);

953

1082

954

1083

end:

955

1084

956

1085

if (debug){

957

1086

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

958

1087

}

963

1092

964

1093

if (mc.server != NULL)

965

1094

avahi_server_free(mc.server);

966

1095

967

1096

if (mc.simple_poll != NULL)

968

1097

avahi_simple_poll_free(mc.simple_poll);

969

free(pubkeyfile);

970

free(seckeyfile);

971

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

972

1146

return exitcode;

973

1147

}