/mandos/trunk : revision 482

9

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

10

*

11

* 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

33

34

#define _LARGEFILE_SOURCE

35

#endif

36

#ifndef _FILE_OFFSET_BITS

34

37

#define _FILE_OFFSET_BITS 64

38

#endif

35

39

36

40

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

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41

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42

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

39

stdout, ferror(), sscanf(),

40

remove() */

43

stdout, ferror(), remove() */

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44

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

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45

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

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

44

srand() */

45

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

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

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strtof(), abort() */

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

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

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50

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

48

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

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

49

52

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

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sockaddr_in6, PF_INET6,

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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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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

55

57

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

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struct in6_addr, inet_pton(),

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connect() */

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inet_pton(), connect() */

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59

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

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60

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

60

61

*/

61

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

62

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

63

strtoimax() */

62

64

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

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65

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

64

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

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

68

#include <netinet/in.h>

70

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

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INET_ADDRSTRLEN, INET6_ADDRSTRLEN

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*/

69

73

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

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

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setgid() */

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

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setgid(), pause() */

72

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

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

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

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78

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

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argp_state, struct argp,

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80

argp_parse(), ARGP_KEY_ARG,

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81

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() */

85

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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88

#ifdef __linux__

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89

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

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#endif

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#endif /* __linux__ */

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91

82

92

/* Avahi */

83

93

/* All Avahi types, constants and functions

117

127

static const char mandos_protocol_version[] = "1";

118

128

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

119

129

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

130

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

131

char *connect_to = NULL;

120

132

121

133

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

122

134

typedef struct {

129

141

gpgme_ctx_t ctx;

130

142

} mandos_context;

131

143

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

145

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

146

.dh_bits = 1024, .priority = "SECURE256"

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

148

149

sig_atomic_t quit_now = 0;

150

int signal_received = 0;

151

132

152

/*

133

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

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* "buffer_capacity" is how much is currently allocated,

153

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

154

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

135

155

* "buffer_length" is how much is already used.

136

156

*/

137

size_t adjustbuffer(char **buffer, size_t buffer_length,

157

size_t incbuffer(char **buffer, size_t buffer_length,

138

158

size_t buffer_capacity){

139

159

if(buffer_length + BUFFER_SIZE > buffer_capacity){

140

160

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

149

169

/*

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170

* Initialize GPGME.

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171

*/

152

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

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static bool init_gpgme(const char *seckey,

153

173

const char *pubkey, const char *tempdir){

154

int ret;

155

174

gpgme_error_t rc;

156

175

gpgme_engine_info_t engine_info;

157

176

160

179

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

161

180

*/

162

181

bool import_key(const char *filename){

182

int ret;

163

183

int fd;

164

184

gpgme_data_t pgp_data;

165

185

176

196

return false;

177

197

}

178

198

179

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

199

rc = gpgme_op_import(mc.ctx, pgp_data);

180

200

if(rc != GPG_ERR_NO_ERROR){

181

201

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

182

202

gpgme_strsource(rc), gpgme_strerror(rc));

192

212

}

193

213

194

214

if(debug){

195

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

215

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

196

216

}

197

217

198

218

/* Init GPGME */

225

245

}

226

246

227

247

/* Create new GPGME "context" */

228

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

248

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

229

249

if(rc != GPG_ERR_NO_ERROR){

230

250

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

231

251

gpgme_strsource(rc), gpgme_strerror(rc));

236

256

return false;

237

257

}

238

258

239

return true;

259

return true;

240

260

}

241

261

242

262

/*

243

263

* Decrypt OpenPGP data.

244

264

* Returns -1 on error

245

265

*/

246

static ssize_t pgp_packet_decrypt(const mandos_context *mc,

247

const char *cryptotext,

266

static ssize_t pgp_packet_decrypt(const char *cryptotext,

248

267

size_t crypto_size,

249

268

char **plaintext){

250

269

gpgme_data_t dh_crypto, dh_plain;

277

296

278

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

279

298

data buffer */

280

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

299

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

281

300

if(rc != GPG_ERR_NO_ERROR){

282

301

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

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gpgme_strsource(rc), gpgme_strerror(rc));

284

303

plaintext_length = -1;

285

304

if(debug){

286

305

gpgme_decrypt_result_t result;

287

result = gpgme_op_decrypt_result(mc->ctx);

306

result = gpgme_op_decrypt_result(mc.ctx);

288

307

if(result == NULL){

289

308

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

290

309

} else {

297

316

}

298

317

gpgme_recipient_t recipient;

299

318

recipient = result->recipients;

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

}

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);

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

326

recipient = recipient->next;

310

327

}

311

328

}

312

329

}

326

343

327

344

*plaintext = NULL;

328

345

while(true){

329

plaintext_capacity = adjustbuffer(plaintext,

346

plaintext_capacity = incbuffer(plaintext,

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(size_t)plaintext_length,

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plaintext_capacity);

332

349

if(plaintext_capacity == 0){

333

perror("adjustbuffer");

350

perror("incbuffer");

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plaintext_length = -1;

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352

goto decrypt_end;

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353

}

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399

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

383

400

}

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385

static int init_gnutls_global(mandos_context *mc,

386

const char *pubkeyfilename,

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static int init_gnutls_global(const char *pubkeyfilename,

387

403

const char *seckeyfilename){

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404

int ret;

389

405

407

423

}

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424

409

425

/* OpenPGP credentials */

410

gnutls_certificate_allocate_credentials(&mc->cred);

426

gnutls_certificate_allocate_credentials(&mc.cred);

411

427

if(ret != GNUTLS_E_SUCCESS){

412

428

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

413

* from

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* -Wunreachable-code

415

*/

429

from

430

-Wunreachable-code

431

*/

416

432

safer_gnutls_strerror(ret));

417

433

gnutls_global_deinit();

418

434

return -1;

425

441

}

426

442

427

443

ret = gnutls_certificate_set_openpgp_key_file

428

(mc->cred, pubkeyfilename, seckeyfilename,

444

(mc.cred, pubkeyfilename, seckeyfilename,

429

445

GNUTLS_OPENPGP_FMT_BASE64);

430

446

if(ret != GNUTLS_E_SUCCESS){

431

447

fprintf(stderr,

437

453

}

438

454

439

455

/* GnuTLS server initialization */

440

ret = gnutls_dh_params_init(&mc->dh_params);

456

ret = gnutls_dh_params_init(&mc.dh_params);

441

457

if(ret != GNUTLS_E_SUCCESS){

442

458

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

443

459

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

444

460

goto globalfail;

445

461

}

446

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

462

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

447

463

if(ret != GNUTLS_E_SUCCESS){

448

464

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

449

465

safer_gnutls_strerror(ret));

450

466

goto globalfail;

451

467

}

452

468

453

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

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

454

470

455

471

return 0;

456

472

457

473

globalfail:

458

474

459

gnutls_certificate_free_credentials(mc->cred);

475

gnutls_certificate_free_credentials(mc.cred);

460

476

gnutls_global_deinit();

461

gnutls_dh_params_deinit(mc->dh_params);

477

gnutls_dh_params_deinit(mc.dh_params);

462

478

return -1;

463

479

}

464

480

465

static int init_gnutls_session(mandos_context *mc,

466

gnutls_session_t *session){

481

static int init_gnutls_session(gnutls_session_t *session){

467

482

int ret;

468

483

/* GnuTLS session creation */

469

ret = gnutls_init(session, GNUTLS_SERVER);

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);

470

490

if(ret != GNUTLS_E_SUCCESS){

471

491

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

472

492

safer_gnutls_strerror(ret));

474

494

475

495

{

476

496

const char *err;

477

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

478

504

if(ret != GNUTLS_E_SUCCESS){

479

505

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

480

506

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

484

510

}

485

511

}

486

512

487

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

488

mc->cred);

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);

489

521

if(ret != GNUTLS_E_SUCCESS){

490

522

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

491

523

safer_gnutls_strerror(ret));

494

526

}

495

527

496

528

/* ignore client certificate if any. */

497

gnutls_certificate_server_set_request(*session,

498

GNUTLS_CERT_IGNORE);

529

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

499

530

500

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

501

532

502

533

return 0;

503

534

}

509

540

/* Called when a Mandos server is found */

510

541

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

511

542

AvahiIfIndex if_index,

512

mandos_context *mc){

513

int ret, tcp_sd;

543

int af){

544

int ret, tcp_sd = -1;

514

545

ssize_t sret;

515

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

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

516

550

char *buffer = NULL;

517

char *decrypted_buffer;

551

char *decrypted_buffer = NULL;

518

552

size_t buffer_length = 0;

519

553

size_t buffer_capacity = 0;

520

ssize_t decrypted_buffer_size;

521

554

size_t written;

522

int retval = 0;

523

char interface[IF_NAMESIZE];

555

int retval = -1;

524

556

gnutls_session_t session;

525

526

ret = init_gnutls_session(mc, &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);

527

580

if(ret != 0){

528

581

return -1;

529

582

}

530

583

531

584

if(debug){

532

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

585

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

533

586

"\n", ip, port);

534

587

}

535

588

536

tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

537

590

if(tcp_sd < 0){

591

int e = errno;

538

592

perror("socket");

539

return -1;

593

errno = e;

594

goto mandos_end;

540

595

}

541

596

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);

597

if(quit_now){

598

errno = EINTR;

599

goto mandos_end;

548

600

}

549

601

550

602

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

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);

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

}

555

610

if(ret < 0 ){

611

int e = errno;

556

612

perror("inet_pton");

557

return -1;

613

errno = e;

614

goto mandos_end;

558

615

}

559

616

if(ret == 0){

617

int e = errno;

560

618

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

561

return -1;

619

errno = e;

620

goto mandos_end;

562

621

}

563

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

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

564

641

-Wconversion and

565

642

-Wunreachable-code */

643

}

566

644

567

to.in6.sin6_scope_id = (uint32_t)if_index;

645

if(quit_now){

646

errno = EINTR;

647

goto mandos_end;

648

}

568

649

569

650

if(debug){

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){

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){

575

674

perror("inet_ntop");

576

675

} else {

577

676

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

580

679

}

581

680

}

582

681

583

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

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

}

584

692

if(ret < 0){

585

perror("connect");

586

return -1;

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;

587

704

}

588

705

589

706

const char *out = mandos_protocol_version;

593

710

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

594

711

out_size - written));

595

712

if(ret == -1){

713

int e = errno;

596

714

perror("write");

597

retval = -1;

715

errno = e;

598

716

goto mandos_end;

599

717

}

600

718

written += (size_t)ret;

608

726

break;

609

727

}

610

728

}

729

730

if(quit_now){

731

errno = EINTR;

732

goto mandos_end;

733

}

611

734

}

612

735

613

736

if(debug){

614

737

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

615

738

}

616

739

740

if(quit_now){

741

errno = EINTR;

742

goto mandos_end;

743

}

744

617

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

618

746

619

do{

747

if(quit_now){

748

errno = EINTR;

749

goto mandos_end;

750

}

751

752

do {

620

753

ret = gnutls_handshake(session);

754

if(quit_now){

755

errno = EINTR;

756

goto mandos_end;

757

}

621

758

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

622

759

623

760

if(ret != GNUTLS_E_SUCCESS){

625

762

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

626

763

gnutls_perror(ret);

627

764

}

628

retval = -1;

765

errno = EPROTO;

629

766

goto mandos_end;

630

767

}

631

768

632

769

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

633

770

634

771

if(debug){

635

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

772

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

636

773

ip);

637

774

}

638

775

639

776

while(true){

640

buffer_capacity = adjustbuffer(&buffer, buffer_length,

777

778

if(quit_now){

779

errno = EINTR;

780

goto mandos_end;

781

}

782

783

buffer_capacity = incbuffer(&buffer, buffer_length,

641

784

buffer_capacity);

642

785

if(buffer_capacity == 0){

643

perror("adjustbuffer");

644

retval = -1;

786

int e = errno;

787

perror("incbuffer");

788

errno = e;

789

goto mandos_end;

790

}

791

792

if(quit_now){

793

errno = EINTR;

645

794

goto mandos_end;

646

795

}

647

796

656

805

case GNUTLS_E_AGAIN:

657

806

break;

658

807

case GNUTLS_E_REHANDSHAKE:

659

do{

808

do {

660

809

ret = gnutls_handshake(session);

810

811

if(quit_now){

812

errno = EINTR;

813

goto mandos_end;

814

}

661

815

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

662

816

if(ret < 0){

663

817

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

664

818

gnutls_perror(ret);

665

retval = -1;

819

errno = EPROTO;

666

820

goto mandos_end;

667

821

}

668

822

break;

669

823

default:

670

824

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

671

825

" encrypted session with Mandos server\n");

672

retval = -1;

673

826

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

errno = EIO;

674

828

goto mandos_end;

675

829

}

676

830

} else {

682

836

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

683

837

}

684

838

685

gnutls_bye(session, GNUTLS_SHUT_RDWR);

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);

686

851

687

852

if(buffer_length > 0){

688

decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,

853

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

689

855

buffer_length,

690

856

&decrypted_buffer);

691

857

if(decrypted_buffer_size >= 0){

858

692

859

written = 0;

693

860

while(written < (size_t) decrypted_buffer_size){

861

if(quit_now){

862

errno = EINTR;

863

goto mandos_end;

864

}

865

694

866

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

695

867

(size_t)decrypted_buffer_size - written,

696

868

stdout);

697

869

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

870

int e = errno;

698

871

if(debug){

699

872

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

700

873

strerror(errno));

701

874

}

702

retval = -1;

703

break;

875

errno = e;

876

goto mandos_end;

704

877

}

705

878

written += (size_t)ret;

706

879

}

707

free(decrypted_buffer);

708

} else {

709

retval = -1;

880

retval = 0;

710

881

}

711

} else {

712

retval = -1;

713

882

}

714

883

715

884

/* Shutdown procedure */

716

885

717

886

mandos_end:

718

free(buffer);

719

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

720

if(ret == -1){

721

perror("close");

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;

722

906

}

723

gnutls_deinit(session);

724

907

return retval;

725

908

}

726

909

727

910

static void resolve_callback(AvahiSServiceResolver *r,

728

911

AvahiIfIndex interface,

729

AVAHI_GCC_UNUSED AvahiProtocol protocol,

912

AvahiProtocol proto,

730

913

AvahiResolverEvent event,

731

914

const char *name,

732

915

const char *type,

737

920

AVAHI_GCC_UNUSED AvahiStringList *txt,

738

921

AVAHI_GCC_UNUSED AvahiLookupResultFlags

739

922

flags,

740

void* userdata){

741

mandos_context *mc = userdata;

923

AVAHI_GCC_UNUSED void* userdata){

742

924

assert(r);

743

925

744

926

/* Called whenever a service has been resolved successfully or

745

927

timed out */

746

928

929

if(quit_now){

930

return;

931

}

932

747

933

switch(event){

748

934

default:

749

935

case AVAHI_RESOLVER_FAILURE:

750

936

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

751

937

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

752

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

938

avahi_strerror(avahi_server_errno(mc.server)));

753

939

break;

754

940

755

941

case AVAHI_RESOLVER_FOUND:

761

947

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

762

948

ip, (intmax_t)interface, port);

763

949

}

764

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

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

765

952

if(ret == 0){

766

avahi_simple_poll_quit(mc->simple_poll);

953

avahi_simple_poll_quit(mc.simple_poll);

767

954

}

768

955

}

769

956

}

779

966

const char *domain,

780

967

AVAHI_GCC_UNUSED AvahiLookupResultFlags

781

968

flags,

782

void* userdata){

783

mandos_context *mc = userdata;

969

AVAHI_GCC_UNUSED void* userdata){

784

970

assert(b);

785

971

786

972

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

787

973

is removed from the LAN */

788

974

975

if(quit_now){

976

return;

977

}

978

789

979

switch(event){

790

980

default:

791

981

case AVAHI_BROWSER_FAILURE:

792

982

793

983

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

794

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

795

avahi_simple_poll_quit(mc->simple_poll);

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

796

986

return;

797

987

798

988

case AVAHI_BROWSER_NEW:

801

991

the callback function is called the Avahi server will free the

802

992

resolver for us. */

803

993

804

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

805

protocol, name, type, domain,

806

AVAHI_PROTO_INET6, 0,

807

resolve_callback, mc)))

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

808

997

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

809

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

998

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

810

999

break;

811

1000

812

1001

case AVAHI_BROWSER_REMOVE:

821

1010

}

822

1011

}

823

1012

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

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

1036

return 0;

1037

}

1038

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

1039

if_entry->d_name);

1040

if(ret < 0){

1041

perror("asprintf");

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

free(flagname);

1048

return 0;

1049

}

1050

free(flagname);

1051

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

1052

/* read line from flags_fd */

1053

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

1054

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

1055

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

1056

if(flagstring == NULL){

1057

perror("malloc");

1058

close(flags_fd);

1059

return 0;

1060

}

1061

while(to_read > 0){

1062

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

1063

(size_t)to_read));

1064

if(ssret == -1){

1065

perror("read");

1066

free(flagstring);

1067

close(flags_fd);

1068

return 0;

1069

}

1070

to_read -= ssret;

1071

if(ssret == 0){

1072

break;

1073

}

1074

}

1075

close(flags_fd);

1076

intmax_t tmpmax;

1077

char *tmp;

1078

errno = 0;

1079

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

1080

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

1081

and not (isspace(*tmp)))

1082

or tmpmax != (ifreq_flags)tmpmax){

1083

if(debug){

1084

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

1085

flagstring, if_entry->d_name);

1086

}

1087

free(flagstring);

1088

return 0;

1089

}

1090

free(flagstring);

1091

ifreq_flags flags = (ifreq_flags)tmpmax;

1092

/* Reject the loopback device */

1093

if(flags & IFF_LOOPBACK){

1094

if(debug){

1095

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

1096

if_entry->d_name);

1097

}

1098

return 0;

1099

}

1100

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

1101

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

1102

if(debug){

1103

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

1104

if_entry->d_name);

1105

}

1106

return 1;

1107

}

1108

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

1109

if(not (flags & IFF_BROADCAST)){

1110

if(debug){

1111

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

1112

if_entry->d_name);

1113

}

1114

return 0;

1115

}

1116

/* Reject non-ARP interfaces (including dummy interfaces) */

1117

if(flags & IFF_NOARP){

1118

if(debug){

1119

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

1120

if_entry->d_name);

1121

}

1122

return 0;

1123

}

1124

/* Accept this device */

1125

if(debug){

1126

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

1127

if_entry->d_name);

1128

}

1129

return 1;

1130

}

1131

824

1132

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

825

1133

AvahiSServiceBrowser *sb = NULL;

826

1134

int error;

827

1135

int ret;

828

1136

intmax_t tmpmax;

829

int numchars;

1137

char *tmp;

830

1138

int exitcode = EXIT_SUCCESS;

831

const char *interface = "eth0";

1139

const char *interface = "";

832

1140

struct ifreq network;

833

int sd;

1141

int sd = -1;

1142

bool take_down_interface = false;

834

1143

uid_t uid;

835

1144

gid_t gid;

836

char *connect_to = NULL;

837

1145

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

838

1146

bool tempdir_created = false;

839

1147

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

840

1148

const char *seckey = PATHDIR "/" SECKEY;

841

1149

const char *pubkey = PATHDIR "/" PUBKEY;

842

1150

843

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

844

.dh_bits = 1024, .priority = "SECURE256"

845

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

846

1151

bool gnutls_initialized = false;

847

1152

bool gpgme_initialized = false;

848

double delay = 2.5;

1153

float delay = 2.5f;

1154

1155

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1156

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1157

1158

uid = getuid();

1159

gid = getgid();

1160

1161

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

1162

errno = 0;

1163

ret = setgid(gid);

1164

if(ret == -1){

1165

perror("setgid");

1166

}

1167

1168

/* Lower user privileges (temporarily) */

1169

errno = 0;

1170

ret = seteuid(uid);

1171

if(ret == -1){

1172

perror("seteuid");

1173

}

1174

1175

if(quit_now){

1176

goto end;

1177

}

849

1178

850

1179

{

851

1180

struct argp_option options[] = {

857

1186

.group = 1 },

858

1187

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

859

1188

.arg = "NAME",

860

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

861

" servers",

1189

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

1190

" Mandos servers",

862

1191

.group = 1 },

863

1192

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

864

1193

.arg = "FILE",

881

1210

.arg = "SECONDS",

882

1211

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

883

1212

.group = 2 },

1213

/*

1214

* These reproduce what we would get without ARGP_NO_HELP

1215

*/

1216

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

1217

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

1218

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

1219

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

1220

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

1221

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

884

1222

{ .name = NULL }

885

1223

};

886

1224

887

1225

error_t parse_opt(int key, char *arg,

888

1226

struct argp_state *state){

1227

errno = 0;

889

1228

switch(key){

890

1229

case 128: /* --debug */

891

1230

debug = true;

903

1242

pubkey = arg;

904

1243

break;

905

1244

case 129: /* --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);

1245

errno = 0;

1246

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

1247

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

1248

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

1249

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

911

1250

}

912

1251

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

913

1252

break;

915

1254

mc.priority = arg;

916

1255

break;

917

1256

case 131: /* --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);

1257

errno = 0;

1258

delay = strtof(arg, &tmp);

1259

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

1260

argp_error(state, "Bad delay");

922

1261

}

923

1262

break;

924

case ARGP_KEY_ARG:

925

argp_usage(state);

926

case ARGP_KEY_END:

1263

/*

1264

* These reproduce what we would get without ARGP_NO_HELP

1265

*/

1266

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

1267

argp_state_help(state, state->out_stream,

1268

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1269

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1270

case -3: /* --usage */

1271

argp_state_help(state, state->out_stream,

1272

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1273

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

1274

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

1275

exit(argp_err_exit_status);

927

1276

break;

928

1277

default:

929

1278

return ARGP_ERR_UNKNOWN;

930

1279

}

931

return 0;

1280

return errno;

932

1281

}

933

1282

934

1283

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

935

1284

.args_doc = "",

936

1285

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

937

1286

" passwords from a Mandos server" };

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");

1287

ret = argp_parse(&argp, argc, argv,

1288

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1289

switch(ret){

1290

case 0:

1291

break;

1292

case ENOMEM:

1293

default:

1294

errno = ret;

1295

perror("argp_parse");

1296

exitcode = EX_OSERR;

1297

goto end;

1298

case EINVAL:

1299

exitcode = EX_USAGE;

1300

goto end;

1301

}

1302

}

1303

1304

if(not debug){

1305

avahi_set_log_function(empty_log);

1306

}

1307

1308

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

1309

struct dirent **direntries;

1310

ret = scandir(sys_class_net, &direntries, good_interface,

1311

alphasort);

1312

if(ret >= 1){

1313

/* Pick the first good interface */

1314

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

1315

if(debug){

1316

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

1317

}

1318

if(interface == NULL){

1319

perror("malloc");

1320

free(direntries);

1321

exitcode = EXIT_FAILURE;

1322

goto end;

1323

}

1324

free(direntries);

1325

} else {

1326

free(direntries);

1327

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

941

1328

exitcode = EXIT_FAILURE;

942

1329

goto end;

943

1330

}

944

1331

}

945

1332

1333

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

1334

from the signal handler */

1335

/* Initialize the pseudo-RNG for Avahi */

1336

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

1337

mc.simple_poll = avahi_simple_poll_new();

1338

if(mc.simple_poll == NULL){

1339

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

1340

exitcode = EX_UNAVAILABLE;

1341

goto end;

1342

}

1343

1344

sigemptyset(&sigterm_action.sa_mask);

1345

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

1346

if(ret == -1){

1347

perror("sigaddset");

1348

exitcode = EX_OSERR;

1349

goto end;

1350

}

1351

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

1352

if(ret == -1){

1353

perror("sigaddset");

1354

exitcode = EX_OSERR;

1355

goto end;

1356

}

1357

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

1358

if(ret == -1){

1359

perror("sigaddset");

1360

exitcode = EX_OSERR;

1361

goto end;

1362

}

1363

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

1364

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

1365

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

1366

*/

1367

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

1368

if(ret == -1){

1369

perror("sigaction");

1370

return EX_OSERR;

1371

}

1372

if(old_sigterm_action.sa_handler != SIG_IGN){

1373

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

1374

if(ret == -1){

1375

perror("sigaction");

1376

exitcode = EX_OSERR;

1377

goto end;

1378

}

1379

}

1380

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

1381

if(ret == -1){

1382

perror("sigaction");

1383

return EX_OSERR;

1384

}

1385

if(old_sigterm_action.sa_handler != SIG_IGN){

1386

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

1387

if(ret == -1){

1388

perror("sigaction");

1389

exitcode = EX_OSERR;

1390

goto end;

1391

}

1392

}

1393

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

1394

if(ret == -1){

1395

perror("sigaction");

1396

return EX_OSERR;

1397

}

1398

if(old_sigterm_action.sa_handler != SIG_IGN){

1399

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

1400

if(ret == -1){

1401

perror("sigaction");

1402

exitcode = EX_OSERR;

1403

goto end;

1404

}

1405

}

1406

946

1407

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

947

{

1408

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

1409

if_index = (AvahiIfIndex) if_nametoindex(interface);

1410

if(if_index == 0){

1411

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

1412

exitcode = EX_UNAVAILABLE;

1413

goto end;

1414

}

1415

1416

if(quit_now){

1417

goto end;

1418

}

1419

1420

/* Re-raise priviliges */

1421

errno = 0;

1422

ret = seteuid(0);

1423

if(ret == -1){

1424

perror("seteuid");

1425

}

1426

948

1427

#ifdef __linux__

949

1428

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

950

messages to mess up the prompt */

1429

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

951

1430

ret = klogctl(8, NULL, 5);

1431

bool restore_loglevel = true;

952

1432

if(ret == -1){

1433

restore_loglevel = false;

953

1434

perror("klogctl");

954

1435

}

955

#endif

1436

#endif /* __linux__ */

956

1437

957

1438

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

958

1439

if(sd < 0){

959

1440

perror("socket");

960

exitcode = EXIT_FAILURE;

1441

exitcode = EX_OSERR;

961

1442

#ifdef __linux__

962

ret = klogctl(7, NULL, 0);

1443

if(restore_loglevel){

1444

ret = klogctl(7, NULL, 0);

1445

if(ret == -1){

1446

perror("klogctl");

1447

}

1448

}

1449

#endif /* __linux__ */

1450

/* Lower privileges */

1451

errno = 0;

1452

ret = seteuid(uid);

963

1453

if(ret == -1){

964

perror("klogctl");

1454

perror("seteuid");

965

1455

}

966

#endif

967

1456

goto end;

968

1457

}

969

1458

strcpy(network.ifr_name, interface);

971

1460

if(ret == -1){

972

1461

perror("ioctl SIOCGIFFLAGS");

973

1462

#ifdef __linux__

974

ret = klogctl(7, NULL, 0);

1463

if(restore_loglevel){

1464

ret = klogctl(7, NULL, 0);

1465

if(ret == -1){

1466

perror("klogctl");

1467

}

1468

}

1469

#endif /* __linux__ */

1470

exitcode = EX_OSERR;

1471

/* Lower privileges */

1472

errno = 0;

1473

ret = seteuid(uid);

975

1474

if(ret == -1){

976

perror("klogctl");

1475

perror("seteuid");

977

1476

}

978

#endif

979

exitcode = EXIT_FAILURE;

980

1477

goto end;

981

1478

}

982

1479

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

983

1480

network.ifr_flags |= IFF_UP;

1481

take_down_interface = true;

984

1482

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

985

1483

if(ret == -1){

986

perror("ioctl SIOCSIFFLAGS");

987

exitcode = EXIT_FAILURE;

1484

take_down_interface = false;

1485

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1486

exitcode = EX_OSERR;

988

1487

#ifdef __linux__

989

ret = klogctl(7, NULL, 0);

1488

if(restore_loglevel){

1489

ret = klogctl(7, NULL, 0);

1490

if(ret == -1){

1491

perror("klogctl");

1492

}

1493

}

1494

#endif /* __linux__ */

1495

/* Lower privileges */

1496

errno = 0;

1497

ret = seteuid(uid);

990

1498

if(ret == -1){

991

perror("klogctl");

1499

perror("seteuid");

992

1500

}

993

#endif

994

1501

goto end;

995

1502

}

996

1503

}

1008

1515

perror("nanosleep");

1009

1516

}

1010

1517

}

1011

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

1012

if(ret == -1){

1013

perror("close");

1518

if(not take_down_interface){

1519

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

1520

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

1521

if(ret == -1){

1522

perror("close");

1523

}

1014

1524

}

1015

1525

#ifdef __linux__

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);

1526

if(restore_loglevel){

1527

/* Restores kernel loglevel to default */

1528

ret = klogctl(7, NULL, 0);

1529

if(ret == -1){

1530

perror("klogctl");

1531

}

1532

}

1533

#endif /* __linux__ */

1534

/* Lower privileges */

1535

errno = 0;

1536

if(take_down_interface){

1537

/* Lower privileges */

1538

ret = seteuid(uid);

1539

if(ret == -1){

1540

perror("seteuid");

1541

}

1542

} else {

1543

/* Lower privileges permanently */

1544

ret = setuid(uid);

1545

if(ret == -1){

1546

perror("setuid");

1547

}

1548

}

1549

}

1550

1551

if(quit_now){

1552

goto end;

1553

}

1554

1555

ret = init_gnutls_global(pubkey, seckey);

1038

1556

if(ret == -1){

1039

1557

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

1040

exitcode = EXIT_FAILURE;

1558

exitcode = EX_UNAVAILABLE;

1041

1559

goto end;

1042

1560

} else {

1043

1561

gnutls_initialized = true;

1044

1562

}

1045

1563

1564

if(quit_now){

1565

goto end;

1566

}

1567

1568

tempdir_created = true;

1046

1569

if(mkdtemp(tempdir) == NULL){

1570

tempdir_created = false;

1047

1571

perror("mkdtemp");

1048

1572

goto end;

1049

1573

}

1050

tempdir_created = true;

1051

1052

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

1574

1575

if(quit_now){

1576

goto end;

1577

}

1578

1579

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

1053

1580

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

1054

exitcode = EXIT_FAILURE;

1581

exitcode = EX_UNAVAILABLE;

1055

1582

goto end;

1056

1583

} else {

1057

1584

gpgme_initialized = true;

1058

1585

}

1059

1586

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;

1587

if(quit_now){

1064

1588

goto end;

1065

1589

}

1066

1590

1070

1594

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

1071

1595

if(address == NULL){

1072

1596

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

1073

exitcode = EXIT_FAILURE;

1074

goto end;

1075

}

1597

exitcode = EX_USAGE;

1598

goto end;

1599

}

1600

1601

if(quit_now){

1602

goto end;

1603

}

1604

1076

1605

uint16_t port;

1077

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

1078

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

1079

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

1606

errno = 0;

1607

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

1608

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

1609

or tmpmax != (uint16_t)tmpmax){

1080

1610

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

1081

exitcode = EXIT_FAILURE;

1082

goto end;

1083

}

1611

exitcode = EX_USAGE;

1612

goto end;

1613

}

1614

1615

if(quit_now){

1616

goto end;

1617

}

1618

1084

1619

port = (uint16_t)tmpmax;

1085

1620

*address = '\0';

1086

1621

address = connect_to;

1087

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

1088

if(ret < 0){

1089

exitcode = EXIT_FAILURE;

1622

/* Colon in address indicates IPv6 */

1623

int af;

1624

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

1625

af = AF_INET6;

1090

1626

} else {

1627

af = AF_INET;

1628

}

1629

1630

if(quit_now){

1631

goto end;

1632

}

1633

1634

while(not quit_now){

1635

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

1636

if(quit_now or ret == 0){

1637

break;

1638

}

1639

sleep(15);

1640

};

1641

1642

if (not quit_now){

1091

1643

exitcode = EXIT_SUCCESS;

1092

1644

}

1645

1093

1646

goto end;

1094

1647

}

1095

1648

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;

1649

if(quit_now){

1108

1650

goto end;

1109

1651

}

1110

1652

1130

1672

if(mc.server == NULL){

1131

1673

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

1132

1674

avahi_strerror(error));

1133

exitcode = EXIT_FAILURE;

1675

exitcode = EX_UNAVAILABLE;

1676

goto end;

1677

}

1678

1679

if(quit_now){

1134

1680

goto end;

1135

1681

}

1136

1682

1137

1683

/* Create the Avahi service browser */

1138

1684

sb = avahi_s_service_browser_new(mc.server, if_index,

1139

AVAHI_PROTO_INET6, "_mandos._tcp",

1140

NULL, 0, browse_callback, &mc);

1685

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1686

NULL, 0, browse_callback, NULL);

1141

1687

if(sb == NULL){

1142

1688

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

1143

1689

avahi_strerror(avahi_server_errno(mc.server)));

1144

exitcode = EXIT_FAILURE;

1690

exitcode = EX_UNAVAILABLE;

1691

goto end;

1692

}

1693

1694

if(quit_now){

1145

1695

goto end;

1146

1696

}

1147

1697

1179

1729

gpgme_release(mc.ctx);

1180

1730

}

1181

1731

1732

/* Take down the network interface */

1733

if(take_down_interface){

1734

/* Re-raise priviliges */

1735

errno = 0;

1736

ret = seteuid(0);

1737

if(ret == -1){

1738

perror("seteuid");

1739

}

1740

if(geteuid() == 0){

1741

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

1742

if(ret == -1){

1743

perror("ioctl SIOCGIFFLAGS");

1744

} else if(network.ifr_flags & IFF_UP) {

1745

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

1746

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

1747

if(ret == -1){

1748

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1749

}

1750

}

1751

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

1752

if(ret == -1){

1753

perror("close");

1754

}

1755

/* Lower privileges permanently */

1756

errno = 0;

1757

ret = setuid(uid);

1758

if(ret == -1){

1759

perror("setuid");

1760

}

1761

}

1762

}

1763

1182

1764

/* Removes the temp directory used by GPGME */

1183

1765

if(tempdir_created){

1184

1766

DIR *d;

1223

1805

}

1224

1806

}

1225

1807

1808

if(quit_now){

1809

sigemptyset(&old_sigterm_action.sa_mask);

1810

old_sigterm_action.sa_handler = SIG_DFL;

1811

ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,

1812

&old_sigterm_action,

1813

NULL));

1814

if(ret == -1){

1815

perror("sigaction");

1816

}

1817

do {

1818

ret = raise(signal_received);

1819

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

1820

if(ret != 0){

1821

perror("raise");

1822

abort();

1823

}

1824

TEMP_FAILURE_RETRY(pause());

1825

}

1826

1226

1827

return exitcode;

1227

1828

}