/mandos/release : revision 237.16.13

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

41

42

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

43

stdout, ferror() */

44

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

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stdout, ferror(), remove() */

44

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

45

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

46

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

47

strtof(), abort() */

55

opendir(), DIR */

56

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

57

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

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inet_pton(), connect(),

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getnameinfo() */

60

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

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inet_pton(), connect() */

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

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60

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

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61

*/

63

62

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

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63

strtoimax() */

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

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

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program_invocation_short_name */

67

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

73

*/

74

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

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

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

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unlinkat() */

78

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

76

setgid(), pause() */

77

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

79

78

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

80

79

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

81

80

argp_state, struct argp,

88

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

89

88

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

90

89

WEXITSTATUS(), WTERMSIG() */

91

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

92

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

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argz_delete(), argz_append(),

94

argz_stringify(), argz_add(),

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

90

99

91

#ifdef __linux__

100

92

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

142

134

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

143

135

char *connect_to = NULL;

144

136

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

148

137

149

138

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

150

139

typedef struct server{

151

140

const char *ip;

152

in_port_t port;

141

uint16_t port;

153

142

AvahiIfIndex if_index;

154

143

int af;

155

144

struct timespec last_seen;

159

148

160

149

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

161

150

typedef struct {

151

AvahiSimplePoll *simple_poll;

162

152

AvahiServer *server;

163

153

gnutls_certificate_credentials_t cred;

164

154

unsigned int dh_bits;

166

156

const char *priority;

167

157

gpgme_ctx_t ctx;

168

158

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

159

} mandos_context;

172

160

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

175

166

176

167

sig_atomic_t quit_now = 0;

177

168

int signal_received = 0;

178

169

179

170

/* Function to use when printing errors */

180

171

void perror_plus(const char *print_text){

181

int e = errno;

182

172

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

183

173

program_invocation_short_name);

184

errno = e;

185

174

perror(print_text);

186

175

}

187

176

188

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

189

177

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

190

178

va_list ap;

191

179

va_start (ap, format);

192

180

193

181

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

194

182

program_invocation_short_name));

195

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

183

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

196

184

}

197

185

198

186

/*

200

188

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

201

189

* "buffer_length" is how much is already used.

202

190

*/

203

__attribute__((nonnull, warn_unused_result))

204

191

size_t incbuffer(char **buffer, size_t buffer_length,

205

192

size_t buffer_capacity){

206

193

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

194

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

195

if(buffer == NULL){

213

196

return 0;

214

197

}

215

*buffer = new_buf;

216

198

buffer_capacity += BUFFER_SIZE;

217

199

}

218

200

return buffer_capacity;

219

201

}

220

202

221

203

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

222

__attribute__((nonnull, warn_unused_result))

223

bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,

224

int af, server **current_server){

204

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

205

int af){

225

206

int ret;

226

207

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

227

208

if(new_server == NULL){

228

209

perror_plus("malloc");

229

return false;

210

return -1;

230

211

}

231

212

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

232

213

.port = port,

234

215

.af = af };

235

216

if(new_server->ip == NULL){

236

217

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

218

return -1;

253

219

}

254

220

/* Special case of first server */

255

if(*current_server == NULL){

221

if (mc.current_server == NULL){

256

222

new_server->next = new_server;

257

223

new_server->prev = new_server;

258

*current_server = new_server;

224

mc.current_server = new_server;

225

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

259

226

} else {

260

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

261

new_server->next = *current_server;

262

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

227

new_server->next = mc.current_server;

228

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

263

229

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

230

mc.current_server->prev = new_server;

231

}

232

ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

267

238

}

268

239

269

240

/*

270

241

* Initialize GPGME.

271

242

*/

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

243

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

244

const char *tempdir){

277

245

gpgme_error_t rc;

278

246

gpgme_engine_info_t engine_info;

279

247

248

280

249

/*

281

250

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

282

251

*/

283

bool import_key(const char * const filename){

252

bool import_key(const char *filename){

284

253

int ret;

285

254

int fd;

286

255

gpgme_data_t pgp_data;

298

267

return false;

299

268

}

300

269

301

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

270

rc = gpgme_op_import(mc.ctx, pgp_data);

302

271

if(rc != GPG_ERR_NO_ERROR){

303

272

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

304

273

gpgme_strsource(rc), gpgme_strerror(rc));

348

317

}

349

318

350

319

/* Create new GPGME "context" */

351

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

320

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

352

321

if(rc != GPG_ERR_NO_ERROR){

353

322

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

354

323

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

367

336

* Decrypt OpenPGP data.

368

337

* Returns -1 on error

369

338

*/

370

__attribute__((nonnull, warn_unused_result))

371

339

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

340

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

341

char **plaintext){

375

342

gpgme_data_t dh_crypto, dh_plain;

376

343

gpgme_error_t rc;

377

344

ssize_t ret;

403

370

404

371

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

405

372

data buffer */

406

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

373

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

407

374

if(rc != GPG_ERR_NO_ERROR){

408

375

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

409

376

gpgme_strsource(rc), gpgme_strerror(rc));

410

377

plaintext_length = -1;

411

378

if(debug){

412

379

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

380

result = gpgme_op_decrypt_result(mc.ctx);

414

381

if(result == NULL){

415

382

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

416

383

} else {

493

460

return plaintext_length;

494

461

}

495

462

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

499

466

if(ret == NULL)

500

467

ret = "(unknown)";

501

468

return ret;

502

469

}

503

470

504

471

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

472

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

507

473

const char* string){

508

474

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

509

475

}

510

476

511

__attribute__((nonnull, warn_unused_result))

512

477

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

478

const char *seckeyfilename){

515

479

int ret;

516

480

517

481

if(debug){

534

498

}

535

499

536

500

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

502

if(ret != GNUTLS_E_SUCCESS){

539

503

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

540

504

safer_gnutls_strerror(ret));

550

514

}

551

515

552

516

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

517

(mc.cred, pubkeyfilename, seckeyfilename,

554

518

GNUTLS_OPENPGP_FMT_BASE64);

555

519

if(ret != GNUTLS_E_SUCCESS){

556

520

fprintf_plus(stderr,

562

526

}

563

527

564

528

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

529

ret = gnutls_dh_params_init(&mc.dh_params);

566

530

if(ret != GNUTLS_E_SUCCESS){

567

531

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

532

" initialization: %s\n",

569

533

safer_gnutls_strerror(ret));

570

534

goto globalfail;

571

535

}

572

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

536

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

573

537

if(ret != GNUTLS_E_SUCCESS){

574

538

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

575

539

safer_gnutls_strerror(ret));

576

540

goto globalfail;

577

541

}

578

542

579

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

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

544

581

545

return 0;

582

546

583

547

globalfail:

584

548

585

gnutls_certificate_free_credentials(mc->cred);

549

gnutls_certificate_free_credentials(mc.cred);

586

550

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

551

gnutls_dh_params_deinit(mc.dh_params);

588

552

return -1;

589

553

}

590

554

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

555

static int init_gnutls_session(gnutls_session_t *session){

594

556

int ret;

595

557

/* GnuTLS session creation */

596

558

do {

608

570

{

609

571

const char *err;

610

572

do {

611

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

573

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

612

574

if(quit_now){

613

575

gnutls_deinit(*session);

614

576

return -1;

625

587

626

588

do {

627

589

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

590

mc.cred);

629

591

if(quit_now){

630

592

gnutls_deinit(*session);

631

593

return -1;

641

603

/* ignore client certificate if any. */

642

604

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

605

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

607

646

608

return 0;

647

609

}

651

613

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

652

614

653

615

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

655

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

616

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

656

617

AvahiIfIndex if_index,

657

int af, mandos_context *mc){

618

int af){

658

619

int ret, tcp_sd = -1;

659

620

ssize_t sret;

660

struct sockaddr_storage to;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

661

625

char *buffer = NULL;

662

626

char *decrypted_buffer = NULL;

663

627

size_t buffer_length = 0;

687

651

return -1;

688

652

}

689

653

690

/* If the interface is specified and we have a list of interfaces */

691

if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){

692

/* Check if the interface is one of the interfaces we are using */

693

bool match = false;

694

{

695

char *interface = NULL;

696

while((interface=argz_next(mc->interfaces, mc->interfaces_size,

697

interface))){

698

if(if_nametoindex(interface) == (unsigned int)if_index){

699

match = true;

700

break;

701

}

702

}

703

}

704

if(not match){

705

/* This interface does not match any in the list, so we don't

706

connect to the server */

707

if(debug){

708

char interface[IF_NAMESIZE];

709

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

710

perror_plus("if_indextoname");

711

} else {

712

fprintf_plus(stderr, "Skipping server on non-used interface"

713

" \"%s\"\n",

714

if_indextoname((unsigned int)if_index,

715

interface));

716

}

717

}

718

return -1;

719

}

720

}

721

722

ret = init_gnutls_session(&session, mc);

654

ret = init_gnutls_session(&session);

723

655

if(ret != 0){

724

656

return -1;

725

657

}

726

658

727

659

if(debug){

728

660

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

729

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

661

PRIu16 "\n", ip, port);

730

662

}

731

663

732

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

744

676

745

677

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

746

678

if(af == AF_INET6){

747

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

748

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

679

to.in6.sin6_family = (sa_family_t)af;

680

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

749

681

} else { /* IPv4 */

750

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

751

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

682

to.in.sin_family = (sa_family_t)af;

683

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

752

684

}

753

685

if(ret < 0 ){

754

686

int e = errno;

763

695

goto mandos_end;

764

696

}

765

697

if(af == AF_INET6){

766

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

767

if(IN6_IS_ADDR_LINKLOCAL

768

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

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

769

705

if(if_index == AVAHI_IF_UNSPEC){

770

706

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

771

707

" incomplete without a network interface\n");

773

709

goto mandos_end;

774

710

}

775

711

/* Set the network interface number as scope */

776

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

712

to.in6.sin6_scope_id = (uint32_t)if_index;

777

713

}

778

714

} else {

779

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

715

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

716

-Wconversion and

717

-Wunreachable-code */

780

718

}

781

719

782

720

if(quit_now){

790

728

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

791

729

perror_plus("if_indextoname");

792

730

} else {

793

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

794

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

731

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

732

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

795

733

}

796

734

} else {

797

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

798

ip, (uintmax_t)port);

735

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

736

ip, port);

799

737

}

800

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

801

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

802

741

if(af == AF_INET6){

803

ret = getnameinfo((struct sockaddr *)&to,

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

742

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

743

sizeof(addrstr));

807

744

} else {

808

ret = getnameinfo((struct sockaddr *)&to,

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

745

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

746

sizeof(addrstr));

812

747

}

813

if(ret == EAI_SYSTEM){

814

perror_plus("getnameinfo");

815

} else if(ret != 0) {

816

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

817

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

818

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);

753

}

819

754

}

820

755

}

821

756

825

760

}

826

761

827

762

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

763

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

830

764

} else {

831

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

832

sizeof(struct sockaddr_in));

765

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

833

766

}

834

767

if(ret < 0){

835

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

768

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

836

769

int e = errno;

837

770

perror_plus("connect");

838

771

errno = e;

884

817

goto mandos_end;

885

818

}

886

819

887

/* This casting via intptr_t is to eliminate warning about casting

888

an int to a pointer type. This is exactly how the GnuTLS Guile

889

function "set-session-transport-fd!" does it. */

890

gnutls_transport_set_ptr(session,

891

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

892

822

893

823

if(quit_now){

894

824

errno = EINTR;

999

929

if(buffer_length > 0){

1000

930

ssize_t decrypted_buffer_size;

1001

931

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1002

&decrypted_buffer, mc);

932

&decrypted_buffer);

1003

933

if(decrypted_buffer_size >= 0){

1004

934

1005

935

written = 0;

1053

983

return retval;

1054

984

}

1055

985

1056

__attribute__((nonnull))

1057

986

static void resolve_callback(AvahiSServiceResolver *r,

1058

987

AvahiIfIndex interface,

1059

988

AvahiProtocol proto,

1067

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1068

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1069

998

flags,

1070

void *mc){

1071

if(r == NULL){

1072

return;

1073

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1074

1001

1075

1002

/* Called whenever a service has been resolved successfully or

1076

1003

timed out */

1077

1004

1078

1005

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1080

1006

return;

1081

1007

}

1082

1008

1086

1012

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

1087

1013

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

1088

1014

domain,

1089

avahi_strerror(avahi_server_errno

1090

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1091

1016

break;

1092

1017

1093

1018

case AVAHI_RESOLVER_FOUND:

1099

1024

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

1100

1025

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

1101

1026

}

1102

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

1103

interface,

1104

avahi_proto_to_af(proto),

1105

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1106

1029

if(ret == 0){

1107

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1108

1031

} else {

1109

if(not add_server(ip, (in_port_t)port, interface,

1110

avahi_proto_to_af(proto),

1111

&((mandos_context*)mc)->current_server)){

1112

fprintf_plus(stderr, "Failed to add server \"%s\" to server"

1113

" list\n", name);

1114

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1115

1034

}

1116

1035

}

1117

1036

}

1127

1046

const char *domain,

1128

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1129

1048

flags,

1130

void *mc){

1131

if(b == NULL){

1132

return;

1133

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1134

1051

1135

1052

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

1136

1053

is removed from the LAN */

1144

1061

case AVAHI_BROWSER_FAILURE:

1145

1062

1146

1063

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

1147

avahi_strerror(avahi_server_errno

1148

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

1149

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1150

1066

return;

1151

1067

1152

1068

case AVAHI_BROWSER_NEW:

1155

1071

the callback function is called the Avahi server will free the

1156

1072

resolver for us. */

1157

1073

1158

if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,

1159

interface, protocol, name, type,

1160

domain, protocol, 0,

1161

resolve_callback, mc) == NULL)

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1162

1077

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

1163

1078

" %s\n", name,

1164

avahi_strerror(avahi_server_errno

1165

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1166

1080

break;

1167

1081

1168

1082

case AVAHI_BROWSER_REMOVE:

1187

1101

signal_received = sig;

1188

1102

int old_errno = errno;

1189

1103

/* set main loop to exit */

1190

if(simple_poll != NULL){

1191

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1192

1106

}

1193

1107

errno = old_errno;

1194

1108

}

1195

1109

1196

__attribute__((nonnull, warn_unused_result))

1197

1110

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

1198

1111

int ret;

1199

error_t ret_errno;

1200

1112

1201

1113

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

1202

1114

if(s < 0){

1203

ret_errno = errno;

1204

1115

perror_plus("socket");

1205

errno = ret_errno;

1206

1116

return false;

1207

1117

}

1208

1118

strcpy(ifr->ifr_name, ifname);

1209

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1210

1120

if(ret == -1){

1211

1121

if(debug){

1212

ret_errno = errno;

1213

1122

perror_plus("ioctl SIOCGIFFLAGS");

1214

errno = ret_errno;

1215

1123

}

1216

1124

return false;

1217

1125

}

1218

1126

return true;

1219

1127

}

1220

1128

1221

__attribute__((nonnull, warn_unused_result))

1222

1129

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

1223

1130

1224

1131

/* Reject the loopback device */

1266

1173

* corresponds to an acceptable network device.

1267

1174

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

1268

1175

*/

1269

__attribute__((nonnull, warn_unused_result))

1270

1176

int good_interface(const struct dirent *if_entry){

1271

1177

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

1272

1178

return 0;

1288

1194

}

1289

1195

1290

1196

/*

1291

* This function determines if a network interface is up.

1292

*/

1293

__attribute__((nonnull, warn_unused_result))

1294

bool interface_is_up(const char *interface){

1295

struct ifreq ifr;

1296

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

1297

if(debug){

1298

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

1299

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

1300

}

1301

return false;

1302

}

1303

1304

return (bool)(ifr.ifr_flags & IFF_UP);

1305

}

1306

1307

/*

1308

* This function determines if a network interface is running

1309

*/

1310

__attribute__((nonnull, warn_unused_result))

1311

bool interface_is_running(const char *interface){

1312

struct ifreq ifr;

1313

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

1314

if(debug){

1315

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

1316

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

1317

}

1318

return false;

1319

}

1320

1321

return (bool)(ifr.ifr_flags & IFF_RUNNING);

1322

}

1323

1324

__attribute__((nonnull, pure, warn_unused_result))

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

if(not get_flags(if_entry->d_name, &ifr)){

1208

if(debug){

1209

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

1210

"\"%s\"\n", if_entry->d_name);

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

if(not (ifr.ifr_flags & IFF_UP)){

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

if(not (ifr.ifr_flags & IFF_RUNNING)){

1226

if(debug){

1227

fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

if(not good_flags(if_entry->d_name, &ifr)){

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1325

1239

int notdotentries(const struct dirent *direntry){

1326

1240

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

1327

1241

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

1334

1248

}

1335

1249

1336

1250

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

1337

__attribute__((nonnull, warn_unused_result))

1338

1251

int runnable_hook(const struct dirent *direntry){

1339

1252

int ret;

1340

1253

size_t sret;

1348

1261

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

1349

1262

"abcdefghijklmnopqrstuvwxyz"

1350

1263

"0123456789"

1351

"_.-");

1264

"_-");

1352

1265

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

1353

1266

/* Contains non-allowed characters */

1354

1267

if(debug){

1358

1271

return 0;

1359

1272

}

1360

1273

1361

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

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1362

1282

if(ret == -1){

1363

1283

if(debug){

1364

1284

perror_plus("Could not stat hook");

1388

1308

return 1;

1389

1309

}

1390

1310

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1394

1312

int ret;

1395

1313

struct timespec now;

1396

1314

struct timespec waited_time;

1397

1315

intmax_t block_time;

1398

1316

1399

1317

while(true){

1400

if(mc->current_server == NULL){

1401

if(debug){

1318

if(mc.current_server == NULL){

1319

if (debug){

1402

1320

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

1403

1321

" No timeout!\n");

1404

1322

}

1405

1323

ret = avahi_simple_poll_iterate(s, -1);

1406

1324

} else {

1407

if(debug){

1325

if (debug){

1408

1326

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

1409

1327

" it, or wait\n");

1410

1328

}

1417

1335

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

1418

1336

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

1419

1337

waited_time.tv_sec = (now.tv_sec

1420

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

1338

- mc.current_server->last_seen.tv_sec);

1421

1339

waited_time.tv_nsec = (now.tv_nsec

1422

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

1340

- mc.current_server->last_seen.tv_nsec);

1423

1341

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

1424

1342

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

1425

1343

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

1427

1345

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

1428

1346

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

1429

1347

1430

if(debug){

1348

if (debug){

1431

1349

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

1432

1350

block_time);

1433

1351

}

1434

1352

1435

1353

if(block_time <= 0){

1436

ret = start_mandos_communication(mc->current_server->ip,

1437

mc->current_server->port,

1438

mc->current_server->if_index,

1439

mc->current_server->af, mc);

1354

ret = start_mandos_communication(mc.current_server->ip,

1355

mc.current_server->port,

1356

mc.current_server->if_index,

1357

mc.current_server->af);

1440

1358

if(ret == 0){

1441

avahi_simple_poll_quit(s);

1359

avahi_simple_poll_quit(mc.simple_poll);

1442

1360

return 0;

1443

1361

}

1444

1362

ret = clock_gettime(CLOCK_MONOTONIC,

1445

&mc->current_server->last_seen);

1363

&mc.current_server->last_seen);

1446

1364

if(ret == -1){

1447

1365

perror_plus("clock_gettime");

1448

1366

return -1;

1449

1367

}

1450

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

1368

mc.current_server = mc.current_server->next;

1451

1369

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

1452

1370

servers, but don't block */

1453

1371

}

1455

1373

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

1456

1374

}

1457

1375

if(ret != 0){

1458

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

1376

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

1459

1377

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

1460

1378

}

1461

1379

}

1462

1380

}

1463

1381

}

1464

1382

1465

/* Set effective uid to 0, return errno */

1466

__attribute__((warn_unused_result))

1467

error_t raise_privileges(void){

1468

error_t old_errno = errno;

1469

error_t ret_errno = 0;

1470

if(seteuid(0) == -1){

1471

ret_errno = errno;

1472

}

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

1477

/* Set effective and real user ID to 0. Return errno. */

1478

__attribute__((warn_unused_result))

1479

error_t raise_privileges_permanently(void){

1480

error_t old_errno = errno;

1481

error_t ret_errno = raise_privileges();

1482

if(ret_errno != 0){

1483

errno = old_errno;

1484

return ret_errno;

1485

}

1486

if(setuid(0) == -1){

1487

ret_errno = errno;

1488

}

1489

errno = old_errno;

1490

return ret_errno;

1491

}

1492

1493

/* Set effective user ID to unprivileged saved user ID */

1494

__attribute__((warn_unused_result))

1495

error_t lower_privileges(void){

1496

error_t old_errno = errno;

1497

error_t ret_errno = 0;

1498

if(seteuid(uid) == -1){

1499

ret_errno = errno;

1500

}

1501

errno = old_errno;

1502

return ret_errno;

1503

}

1504

1505

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1507

error_t lower_privileges_permanently(void){

1508

error_t old_errno = errno;

1509

error_t ret_errno = 0;

1510

if(setuid(uid) == -1){

1511

ret_errno = errno;

1512

}

1513

errno = old_errno;

1514

return ret_errno;

1515

}

1516

1517

__attribute__((nonnull))

1518

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

1383

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

1519

1384

const float delay){

1520

struct dirent **direntries = NULL;

1521

if(hookdir_fd == -1){

1522

hookdir_fd = open(hookdir, O_RDONLY);

1523

if(hookdir_fd == -1){

1524

if(errno == ENOENT){

1525

if(debug){

1526

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1527

" found\n", hookdir);

1528

}

1529

} else {

1530

perror_plus("open");

1531

}

1532

return;

1533

}

1534

}

1535

#ifdef __GLIBC__

1536

#if __GLIBC_PREREQ(2, 15)

1537

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1538

runnable_hook, alphasort);

1539

#else /* not __GLIBC_PREREQ(2, 15) */

1540

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

1541

alphasort);

1542

#endif /* not __GLIBC_PREREQ(2, 15) */

1543

#else /* not __GLIBC__ */

1544

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

1545

alphasort);

1546

#endif /* not __GLIBC__ */

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

1547

1390

if(numhooks == -1){

1548

1391

perror_plus("scandir");

1549

return;

1550

}

1551

struct dirent *direntry;

1552

int ret;

1553

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

1554

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

1555

direntry = direntries[i];

1556

if(debug){

1557

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1558

direntry->d_name);

1559

}

1560

pid_t hook_pid = fork();

1561

if(hook_pid == 0){

1562

/* Child */

1563

/* Raise privileges */

1564

errno = raise_privileges_permanently();

1565

if(errno != 0){

1566

perror_plus("Failed to raise privileges");

1567

_exit(EX_NOPERM);

1568

}

1569

/* Set group */

1570

errno = 0;

1571

ret = setgid(0);

1572

if(ret == -1){

1573

perror_plus("setgid");

1574

_exit(EX_NOPERM);

1575

}

1576

/* Reset supplementary groups */

1577

errno = 0;

1578

ret = setgroups(0, NULL);

1579

if(ret == -1){

1580

perror_plus("setgroups");

1581

_exit(EX_NOPERM);

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

perror_plus("dup2(devnull, STDIN_FILENO)");

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

1596

_exit(EX_OSERR);

1597

}

1598

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

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

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

1604

if(ret == -1){

1605

perror_plus("setenv");

1606

_exit(EX_OSERR);

1607

}

1608

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

1609

if(ret == -1){

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

perror_plus("setenv");

1616

_exit(EX_OSERR);

1617

}

1618

char *delaystring;

1619

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

1620

if(ret == -1){

1392

} else {

1393

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

1394

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

1395

direntry = direntries[i];

1396

char *fullname = NULL;

1397

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

1398

if(ret < 0){

1621

1399

perror_plus("asprintf");

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

if(ret == -1){

1400

continue;

1401

}

1402

if(debug){

1403

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1404

direntry->d_name);

1405

}

1406

pid_t hook_pid = fork();

1407

if(hook_pid == 0){

1408

/* Child */

1409

dup2(devnull, STDIN_FILENO);

1410

close(devnull);

1411

dup2(STDERR_FILENO, STDOUT_FILENO);

1412

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

1413

if(ret == -1){

1414

perror_plus("setenv");

1415

return false;

1416

}

1417

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

1418

if(ret == -1){

1419

perror_plus("setenv");

1420

return false;

1421

}

1422

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

1423

if(ret == -1){

1424

perror_plus("setenv");

1425

return false;

1426

}

1427

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

1428

if(ret == -1){

1429

perror_plus("setenv");

1430

return false;

1431

}

1432

char *delaystring;

1433

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

1434

if(ret == -1){

1435

perror_plus("asprintf");

1436

return false;

1437

}

1438

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

1439

if(ret == -1){

1440

free(delaystring);

1441

perror_plus("setenv");

1442

return false;

1443

}

1626

1444

free(delaystring);

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

ret = setenv("CONNECT", connect_to, 1);

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

if(hook_pid == -1){

1654

perror_plus("fork");

1655

free(direntry);

1656

continue;

1657

}

1658

int status;

1659

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

1660

perror_plus("waitpid");

1661

free(direntry);

1662

continue;

1663

}

1664

if(WIFEXITED(status)){

1665

if(WEXITSTATUS(status) != 0){

1666

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

1667

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

1668

WEXITSTATUS(status));

1669

free(direntry);

1670

continue;

1671

}

1672

} else if(WIFSIGNALED(status)){

1673

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

1674

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

1675

WTERMSIG(status));

1676

free(direntry);

1677

continue;

1678

} else {

1679

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

1680

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

1681

free(direntry);

1682

continue;

1683

}

1684

}

1685

if(debug){

1686

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1687

direntry->d_name);

1688

}

1689

free(direntry);

1690

}

1691

free(direntries);

1692

if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){

1693

perror_plus("close");

1694

} else {

1695

hookdir_fd = -1;

1696

}

1697

close(devnull);

1698

}

1699

1700

__attribute__((nonnull, warn_unused_result))

1701

error_t bring_up_interface(const char *const interface,

1702

const float delay){

1703

error_t old_errno = errno;

1704

int ret;

1705

struct ifreq network;

1706

unsigned int if_index = if_nametoindex(interface);

1707

if(if_index == 0){

1708

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

1709

errno = old_errno;

1710

return ENXIO;

1711

}

1712

1713

if(quit_now){

1714

errno = old_errno;

1715

return EINTR;

1716

}

1717

1718

if(not interface_is_up(interface)){

1719

error_t ret_errno = 0, ioctl_errno = 0;

1720

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

1721

ret_errno = errno;

1722

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

1723

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

1724

errno = old_errno;

1725

return ret_errno;

1726

}

1727

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

1728

1729

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

1730

if(sd == -1){

1731

ret_errno = errno;

1732

perror_plus("socket");

1733

errno = old_errno;

1734

return ret_errno;

1735

}

1736

1737

if(quit_now){

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

errno = old_errno;

1743

return EINTR;

1744

}

1745

1746

if(debug){

1747

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

1748

interface);

1749

}

1750

1751

/* Raise privileges */

1752

ret_errno = raise_privileges();

1753

if(ret_errno != 0){

1754

errno = ret_errno;

1755

perror_plus("Failed to raise privileges");

1756

}

1757

1758

#ifdef __linux__

1759

int ret_linux;

1760

bool restore_loglevel = false;

1761

if(ret_errno == 0){

1762

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1763

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

1764

ret_linux = klogctl(8, NULL, 5);

1765

if(ret_linux == -1){

1766

perror_plus("klogctl");

1767

} else {

1768

restore_loglevel = true;

1769

}

1770

}

1771

#endif /* __linux__ */

1772

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

1773

ioctl_errno = errno;

1774

#ifdef __linux__

1775

if(restore_loglevel){

1776

ret_linux = klogctl(7, NULL, 0);

1777

if(ret_linux == -1){

1778

perror_plus("klogctl");

1779

}

1780

}

1781

#endif /* __linux__ */

1782

1783

/* If raise_privileges() succeeded above */

1784

if(ret_errno == 0){

1785

/* Lower privileges */

1786

ret_errno = lower_privileges();

1787

if(ret_errno != 0){

1788

errno = ret_errno;

1789

perror_plus("Failed to lower privileges");

1790

}

1791

}

1792

1793

/* Close the socket */

1794

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

1795

if(ret == -1){

1796

perror_plus("close");

1797

}

1798

1799

if(ret_setflags == -1){

1800

errno = ioctl_errno;

1801

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1802

errno = old_errno;

1803

return ioctl_errno;

1804

}

1805

} else if(debug){

1806

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

1807

interface);

1808

}

1809

1810

/* Sleep checking until interface is running.

1811

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

1812

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

1813

if(interface_is_running(interface)){

1814

break;

1815

}

1816

struct timespec sleeptime = { .tv_nsec = 250000000 };

1817

ret = nanosleep(&sleeptime, NULL);

1818

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

1819

perror_plus("nanosleep");

1820

}

1821

}

1822

1823

errno = old_errno;

1824

return 0;

1825

}

1826

1827

__attribute__((nonnull, warn_unused_result))

1828

error_t take_down_interface(const char *const interface){

1829

error_t old_errno = errno;

1830

struct ifreq network;

1831

unsigned int if_index = if_nametoindex(interface);

1832

if(if_index == 0){

1833

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

1834

errno = old_errno;

1835

return ENXIO;

1836

}

1837

if(interface_is_up(interface)){

1838

error_t ret_errno = 0, ioctl_errno = 0;

1839

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

1840

ret_errno = errno;

1841

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

1842

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

1843

errno = old_errno;

1844

return ret_errno;

1845

}

1846

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

1847

1848

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

1849

if(sd == -1){

1850

ret_errno = errno;

1851

perror_plus("socket");

1852

errno = old_errno;

1853

return ret_errno;

1854

}

1855

1856

if(debug){

1857

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

1858

interface);

1859

}

1860

1861

/* Raise privileges */

1862

ret_errno = raise_privileges();

1863

if(ret_errno != 0){

1864

errno = ret_errno;

1865

perror_plus("Failed to raise privileges");

1866

}

1867

1868

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

1869

ioctl_errno = errno;

1870

1871

/* If raise_privileges() succeeded above */

1872

if(ret_errno == 0){

1873

/* Lower privileges */

1874

ret_errno = lower_privileges();

1875

if(ret_errno != 0){

1876

errno = ret_errno;

1877

perror_plus("Failed to lower privileges");

1878

}

1879

}

1880

1881

/* Close the socket */

1882

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

1883

if(ret == -1){

1884

perror_plus("close");

1885

}

1886

1887

if(ret_setflags == -1){

1888

errno = ioctl_errno;

1889

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1890

errno = old_errno;

1891

return ioctl_errno;

1892

}

1893

} else if(debug){

1894

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

1895

interface);

1896

}

1897

1898

errno = old_errno;

1899

return 0;

1445

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

1446

perror_plus("execl");

1447

} else {

1448

int status;

1449

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

1450

perror_plus("waitpid");

1451

free(fullname);

1452

continue;

1453

}

1454

if(WIFEXITED(status)){

1455

if(WEXITSTATUS(status) != 0){

1456

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

1457

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

1458

WEXITSTATUS(status));

1459

free(fullname);

1460

continue;

1461

}

1462

} else if(WIFSIGNALED(status)){

1463

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

1464

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

1465

WTERMSIG(status));

1466

free(fullname);

1467

continue;

1468

} else {

1469

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

1470

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

1471

free(fullname);

1472

continue;

1473

}

1474

}

1475

free(fullname);

1476

if(debug){

1477

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1478

direntry->d_name);

1479

}

1480

}

1481

close(devnull);

1482

}

1483

return true;

1900

1484

}

1901

1485

1902

1486

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

1903

mandos_context mc = { .server = NULL, .dh_bits = 1024,

1904

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

1905

"+CTYPE-OPENPGP", .current_server = NULL,

1906

.interfaces = NULL, .interfaces_size = 0 };

1907

1487

AvahiSServiceBrowser *sb = NULL;

1908

error_t ret_errno;

1488

int error;

1909

1489

int ret;

1910

1490

intmax_t tmpmax;

1911

1491

char *tmp;

1912

1492

int exitcode = EXIT_SUCCESS;

1913

char *interfaces_to_take_down = NULL;

1914

size_t interfaces_to_take_down_size = 0;

1915

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

1916

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

1917

char *tempdir = NULL;

1493

const char *interface = "";

1494

struct ifreq network;

1495

int sd = -1;

1496

bool take_down_interface = false;

1497

uid_t uid;

1498

gid_t gid;

1499

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

1500

bool tempdir_created = false;

1918

1501

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1919

1502

const char *seckey = PATHDIR "/" SECKEY;

1920

1503

const char *pubkey = PATHDIR "/" PUBKEY;

1921

char *interfaces_hooks = NULL;

1922

1504

1923

1505

bool gnutls_initialized = false;

1924

1506

bool gpgme_initialized = false;

1986

1568

.group = 2 },

1987

1569

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

1988

1570

.arg = "SECONDS",

1989

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

1571

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

1990

1572

.group = 2 },

1991

1573

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

1992

1574

.arg = "DIR",

2015

1597

connect_to = arg;

2016

1598

break;

2017

1599

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

2018

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

2019

arg, (int)',');

2020

if(ret_errno != 0){

2021

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

2022

}

1600

interface = arg;

2023

1601

break;

2024

1602

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

2025

1603

seckey = arg;

2068

1646

argp_state_help(state, state->out_stream,

2069

1647

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2070

1648

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

2071

1651

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

2072

1652

exit(argp_err_exit_status);

2073

1653

break;

2098

1678

}

2099

1679

}

2100

1680

2101

{

1681

if(getuid() == 0){

2102

1682

/* Work around Debian bug #633582:

2103

1683

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

2104

2105

/* Re-raise privileges */

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2109

perror_plus("Failed to raise privileges");

2110

} else {

2111

struct stat st;

2112

2113

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

2114

int seckey_fd = open(seckey, O_RDONLY);

2115

if(seckey_fd == -1){

2116

perror_plus("open");

2117

} else {

2118

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

2119

if(ret == -1){

2120

perror_plus("fstat");

2121

} else {

2122

if(S_ISREG(st.st_mode)

2123

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

2124

ret = fchown(seckey_fd, uid, gid);

2125

if(ret == -1){

2126

perror_plus("fchown");

2127

}

2128

}

2129

}

2130

TEMP_FAILURE_RETRY(close(seckey_fd));

2131

}

2132

}

2133

2134

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

2135

int pubkey_fd = open(pubkey, O_RDONLY);

2136

if(pubkey_fd == -1){

2137

perror_plus("open");

2138

} else {

2139

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

2140

if(ret == -1){

2141

perror_plus("fstat");

2142

} else {

2143

if(S_ISREG(st.st_mode)

2144

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

2145

ret = fchown(pubkey_fd, uid, gid);

2146

if(ret == -1){

2147

perror_plus("fchown");

2148

}

2149

}

2150

}

2151

TEMP_FAILURE_RETRY(close(pubkey_fd));

2152

}

2153

}

2154

2155

/* Lower privileges */

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2159

perror_plus("Failed to lower privileges");

2160

}

2161

}

2162

}

2163

2164

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

2165

{

2166

char *interface = NULL;

2167

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

2168

interface))){

2169

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

2170

and if_nametoindex(interface) == 0){

2171

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

2172

fprintf_plus(stderr, "Not using nonexisting interface"

2173

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

2174

}

2175

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

2176

interface = NULL;

2177

}

1684

struct stat st;

1685

1686

/* Re-raise priviliges */

1687

errno = 0;

1688

ret = seteuid(0);

1689

if(ret == -1){

1690

perror_plus("seteuid");

1691

}

1692

1693

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

1694

int seckey_fd = open(seckey, O_RDONLY);

1695

if(seckey_fd == -1){

1696

perror_plus("open");

1697

} else {

1698

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

1699

if(ret == -1){

1700

perror_plus("fstat");

1701

} else {

1702

if(S_ISREG(st.st_mode)

1703

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

1704

ret = fchown(seckey_fd, uid, gid);

1705

if(ret == -1){

1706

perror_plus("fchown");

1707

}

1708

}

1709

}

1710

TEMP_FAILURE_RETRY(close(seckey_fd));

1711

}

1712

}

1713

1714

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

1715

int pubkey_fd = open(pubkey, O_RDONLY);

1716

if(pubkey_fd == -1){

1717

perror_plus("open");

1718

} else {

1719

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

1720

if(ret == -1){

1721

perror_plus("fstat");

1722

} else {

1723

if(S_ISREG(st.st_mode)

1724

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

1725

ret = fchown(pubkey_fd, uid, gid);

1726

if(ret == -1){

1727

perror_plus("fchown");

1728

}

1729

}

1730

}

1731

TEMP_FAILURE_RETRY(close(pubkey_fd));

1732

}

1733

}

1734

1735

/* Lower privileges */

1736

errno = 0;

1737

ret = seteuid(uid);

1738

if(ret == -1){

1739

perror_plus("seteuid");

2178

1740

}

2179

1741

}

2180

1742

2181

1743

/* Run network hooks */

2182

1744

{

2183

if(mc.interfaces != NULL){

2184

interfaces_hooks = malloc(mc.interfaces_size);

2185

if(interfaces_hooks == NULL){

2186

perror_plus("malloc");

2187

goto end;

2188

}

2189

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

2190

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

2191

}

2192

run_network_hooks("start", interfaces_hooks != NULL ?

2193

interfaces_hooks : "", delay);

1745

if(getuid() == 0){

1746

/* Re-raise priviliges */

1747

errno = 0;

1748

ret = seteuid(0);

1749

if(ret == -1){

1750

perror_plus("seteuid");

1751

}

1752

}

1753

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

1754

goto end;

1755

}

1756

if(getuid() == 0){

1757

/* Lower privileges */

1758

errno = 0;

1759

ret = seteuid(uid);

1760

if(ret == -1){

1761

perror_plus("seteuid");

1762

}

1763

}

2194

1764

}

2195

1765

2196

1766

if(not debug){

2197

1767

avahi_set_log_function(empty_log);

2198

1768

}

2199

1769

1770

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

1771

struct dirent **direntries;

1772

/* First look for interfaces that are up */

1773

ret = scandir(sys_class_net, &direntries, up_interface,

1774

alphasort);

1775

if(ret == 0){

1776

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

1777

free(direntries);

1778

ret = scandir(sys_class_net, &direntries, good_interface,

1779

alphasort);

1780

}

1781

if(ret >= 1){

1782

/* Pick the first interface returned */

1783

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

1784

if(debug){

1785

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

1786

}

1787

if(interface == NULL){

1788

perror_plus("malloc");

1789

free(direntries);

1790

exitcode = EXIT_FAILURE;

1791

goto end;

1792

}

1793

free(direntries);

1794

} else {

1795

free(direntries);

1796

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

1797

exitcode = EXIT_FAILURE;

1798

goto end;

1799

}

1800

}

1801

2200

1802

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

2201

1803

from the signal handler */

2202

1804

/* Initialize the pseudo-RNG for Avahi */

2203

1805

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

2204

simple_poll = avahi_simple_poll_new();

2205

if(simple_poll == NULL){

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2206

1808

fprintf_plus(stderr,

2207

1809

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

2208

1810

exitcode = EX_UNAVAILABLE;

2272

1874

}

2273

1875

}

2274

1876

2275

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

2276

if(mc.interfaces == NULL){

2277

struct dirent **direntries = NULL;

2278

/* Look for any good interfaces */

2279

ret = scandir(sys_class_net, &direntries, good_interface,

2280

alphasort);

2281

if(ret >= 1){

2282

/* Add all found interfaces to interfaces list */

2283

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

2284

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

2285

direntries[i]->d_name);

2286

if(ret_errno != 0){

2287

errno = ret_errno;

2288

perror_plus("argz_add");

2289

free(direntries[i]);

2290

continue;

2291

}

2292

if(debug){

2293

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

2294

direntries[i]->d_name);

2295

}

2296

free(direntries[i]);

2297

}

2298

free(direntries);

2299

} else {

2300

if(ret == 0){

2301

free(direntries);

2302

}

2303

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

2304

exitcode = EXIT_FAILURE;

2305

goto end;

2306

}

2307

}

2308

2309

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

2310

{

2311

char *interface = NULL;

2312

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

2313

interface))){

2314

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

2315

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

2316

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

2317

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

2318

interface);

2319

interface = NULL;

2320

while((interface = argz_next(mc.interfaces,

2321

mc.interfaces_size, interface))){

2322

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

2323

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

2324

interface);

2325

interface = NULL;

1877

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

1878

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

1879

if_index = (AvahiIfIndex) if_nametoindex(interface);

1880

if(if_index == 0){

1881

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

1882

exitcode = EX_UNAVAILABLE;

1883

goto end;

1884

}

1885

1886

if(quit_now){

1887

goto end;

1888

}

1889

1890

/* Re-raise priviliges */

1891

errno = 0;

1892

ret = seteuid(0);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

1897

#ifdef __linux__

1898

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1899

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

1900

ret = klogctl(8, NULL, 5);

1901

bool restore_loglevel = true;

1902

if(ret == -1){

1903

restore_loglevel = false;

1904

perror_plus("klogctl");

1905

}

1906

#endif /* __linux__ */

1907

1908

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1909

if(sd < 0){

1910

perror_plus("socket");

1911

exitcode = EX_OSERR;

1912

#ifdef __linux__

1913

if(restore_loglevel){

1914

ret = klogctl(7, NULL, 0);

1915

if(ret == -1){

1916

perror_plus("klogctl");

1917

}

1918

}

1919

#endif /* __linux__ */

1920

/* Lower privileges */

1921

errno = 0;

1922

ret = seteuid(uid);

1923

if(ret == -1){

1924

perror_plus("seteuid");

1925

}

1926

goto end;

1927

}

1928

strcpy(network.ifr_name, interface);

1929

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

1930

if(ret == -1){

1931

perror_plus("ioctl SIOCGIFFLAGS");

1932

#ifdef __linux__

1933

if(restore_loglevel){

1934

ret = klogctl(7, NULL, 0);

1935

if(ret == -1){

1936

perror_plus("klogctl");

1937

}

1938

}

1939

#endif /* __linux__ */

1940

exitcode = EX_OSERR;

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

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

1950

network.ifr_flags |= IFF_UP;

1951

take_down_interface = true;

1952

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

1953

if(ret == -1){

1954

take_down_interface = false;

1955

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1956

exitcode = EX_OSERR;

1957

#ifdef __linux__

1958

if(restore_loglevel){

1959

ret = klogctl(7, NULL, 0);

1960

if(ret == -1){

1961

perror_plus("klogctl");

2326

1962

}

2327

1963

}

1964

#endif /* __linux__ */

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

}

1974

/* Sleep checking until interface is running.

1975

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

1976

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

1977

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

1978

if(ret == -1){

1979

perror_plus("ioctl SIOCGIFFLAGS");

1980

} else if(network.ifr_flags & IFF_RUNNING){

2328

1981

break;

2329

1982

}

2330

bool interface_was_up = interface_is_up(interface);

2331

errno = bring_up_interface(interface, delay);

2332

if(not interface_was_up){

2333

if(errno != 0){

2334

perror_plus("Failed to bring up interface");

2335

} else {

2336

errno = argz_add(&interfaces_to_take_down,

2337

&interfaces_to_take_down_size,

2338

interface);

2339

if(errno != 0){

2340

perror_plus("argz_add");

2341

}

2342

}

2343

}

2344

}

2345

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

2346

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

2347

}

2348

}

2349

2350

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

2351

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

2352

if(debug){

2353

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

2354

mc.interfaces);

2355

}

2356

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

1983

struct timespec sleeptime = { .tv_nsec = 250000000 };

1984

ret = nanosleep(&sleeptime, NULL);

1985

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

1986

perror_plus("nanosleep");

1987

}

1988

}

1989

if(not take_down_interface){

1990

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

1991

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

1992

if(ret == -1){

1993

perror_plus("close");

1994

}

1995

}

1996

#ifdef __linux__

1997

if(restore_loglevel){

1998

/* Restores kernel loglevel to default */

1999

ret = klogctl(7, NULL, 0);

2000

if(ret == -1){

2001

perror_plus("klogctl");

2002

}

2003

}

2004

#endif /* __linux__ */

2005

/* Lower privileges */

2006

errno = 0;

2007

/* Lower privileges */

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2011

}

2357

2012

}

2358

2013

2359

2014

if(quit_now){

2360

2015

goto end;

2361

2016

}

2362

2017

2363

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

2018

ret = init_gnutls_global(pubkey, seckey);

2364

2019

if(ret == -1){

2365

2020

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

2366

2021

exitcode = EX_UNAVAILABLE;

2373

2028

goto end;

2374

2029

}

2375

2030

2376

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

2377

tempdir = mkdtemp(run_tempdir);

2378

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

2379

if(debug){

2380

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

2381

run_tempdir, old_tempdir);

2382

}

2383

tempdir = mkdtemp(old_tempdir);

2384

}

2385

if(tempdir == NULL){

2031

if(mkdtemp(tempdir) == NULL){

2386

2032

perror_plus("mkdtemp");

2387

2033

goto end;

2388

2034

}

2035

tempdir_created = true;

2389

2036

2390

2037

if(quit_now){

2391

2038

goto end;

2392

2039

}

2393

2040

2394

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

2041

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

2395

2042

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

2396

2043

exitcode = EX_UNAVAILABLE;

2397

2044

goto end;

2407

2054

/* Connect directly, do not use Zeroconf */

2408

2055

/* (Mainly meant for debugging) */

2409

2056

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

2410

2411

2057

if(address == NULL){

2412

2058

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

2413

2059

exitcode = EX_USAGE;

2418

2064

goto end;

2419

2065

}

2420

2066

2421

in_port_t port;

2067

uint16_t port;

2422

2068

errno = 0;

2423

2069

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

2424

2070

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

2425

or tmpmax != (in_port_t)tmpmax){

2071

or tmpmax != (uint16_t)tmpmax){

2426

2072

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

2427

2073

exitcode = EX_USAGE;

2428

2074

goto end;

2429

2075

}

2430

2076

2431

2077

if(quit_now){

2432

2078

goto end;

2433

2079

}

2434

2080

2435

port = (in_port_t)tmpmax;

2081

port = (uint16_t)tmpmax;

2436

2082

*address = '\0';

2437

2083

/* Colon in address indicates IPv6 */

2438

2084

int af;

2454

2100

}

2455

2101

2456

2102

while(not quit_now){

2457

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

2458

&mc);

2103

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

2459

2104

if(quit_now or ret == 0){

2460

2105

break;

2461

2106

}

2463

2108

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

2464

2109

(int)retry_interval);

2465

2110

}

2466

sleep((unsigned int)retry_interval);

2111

sleep((int)retry_interval);

2467

2112

}

2468

2113

2469

if(not quit_now){

2114

if (not quit_now){

2470

2115

exitcode = EXIT_SUCCESS;

2471

2116

}

2472

2117

2487

2132

config.publish_domain = 0;

2488

2133

2489

2134

/* Allocate a new server */

2490

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2491

&config, NULL, NULL, &ret_errno);

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

2492

2138

2493

2139

/* Free the Avahi configuration data */

2494

2140

avahi_server_config_free(&config);

2497

2143

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

2498

2144

if(mc.server == NULL){

2499

2145

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

2500

avahi_strerror(ret_errno));

2146

avahi_strerror(error));

2501

2147

exitcode = EX_UNAVAILABLE;

2502

2148

goto end;

2503

2149

}

2509

2155

/* Create the Avahi service browser */

2510

2156

sb = avahi_s_service_browser_new(mc.server, if_index,

2511

2157

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2512

NULL, 0, browse_callback,

2513

(void *)&mc);

2158

NULL, 0, browse_callback, NULL);

2514

2159

if(sb == NULL){

2515

2160

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

2516

2161

avahi_strerror(avahi_server_errno(mc.server)));

2527

2172

if(debug){

2528

2173

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

2529

2174

}

2530

2531

ret = avahi_loop_with_timeout(simple_poll,

2532

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

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

2533

2178

if(debug){

2534

2179

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

2535

2180

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

2542

2187

}

2543

2188

2544

2189

/* Cleanup things */

2545

free(mc.interfaces);

2546

2547

2190

if(sb != NULL)

2548

2191

avahi_s_service_browser_free(sb);

2549

2192

2550

2193

if(mc.server != NULL)

2551

2194

avahi_server_free(mc.server);

2552

2195

2553

if(simple_poll != NULL)

2554

avahi_simple_poll_free(simple_poll);

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

2555

2198

2556

2199

if(gnutls_initialized){

2557

2200

gnutls_certificate_free_credentials(mc.cred);

2569

2212

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

2570

2213

while(mc.current_server != NULL){

2571

2214

server *next = mc.current_server->next;

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic push

2574

#pragma GCC diagnostic ignored "-Wcast-qual"

2575

#endif

2576

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

2577

#ifdef __GNUC__

2578

#pragma GCC diagnostic pop

2579

#endif

2580

2215

free(mc.current_server);

2581

2216

mc.current_server = next;

2582

2217

}

2583

2218

}

2584

2219

2585

/* Re-raise privileges */

2220

/* Re-raise priviliges */

2586

2221

{

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2614

}

2615

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

2619

perror_plus("Failed to lower privileges permanently");

2620

}

2621

}

2622

2623

free(interfaces_to_take_down);

2624

free(interfaces_hooks);

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

2227

}

2228

}

2229

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Take down the network interface */

2234

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

2235

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

2236

if(ret == -1){

2237

perror_plus("ioctl SIOCGIFFLAGS");

2238

} else if(network.ifr_flags & IFF_UP){

2239

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

2240

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

2241

if(ret == -1){

2242

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2243

}

2244

}

2245

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

2246

if(ret == -1){

2247

perror_plus("close");

2248

}

2249

}

2250

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

2258

}

2625

2259

2626

2260

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

2627

if(tempdir != NULL){

2261

if(tempdir_created){

2628

2262

struct dirent **direntries = NULL;

2629

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

#else /* not __GLIBC_PREREQ(2, 15) */

2639

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

2640

alphasort);

2641

#endif /* not __GLIBC_PREREQ(2, 15) */

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2649

if(ret == -1){

2650

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2651

" \"%s\", 0): %s\n", tempdir,

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

2267

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

2268

direntry = direntries[i];

2269

char *fullname = NULL;

2270

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

2271

direntry->d_name);

2272

if(ret < 0){

2273

perror_plus("asprintf");

2274

continue;

2275

}

2276

ret = remove(fullname);

2277

if(ret == -1){

2278

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

2279

strerror(errno));

2280

}

2281

free(fullname);

2666

2282

}

2667

TEMP_FAILURE_RETRY(close(tempdir_fd));

2283

}

2284

2285

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

2286

free(direntries);

2287

if (numentries == -1){

2288

perror_plus("scandir");

2289

}

2290

ret = rmdir(tempdir);

2291

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

2292

perror_plus("rmdir");

2668

2293

}

2669

2294

}

2670

2295