/mandos/trunk : revision 599

9

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

10

*

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* Everything else is

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13

12

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

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() */

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42

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

43

stdout, ferror() */

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stdout, ferror(), remove() */

44

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

45

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

46

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

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,

73

72

*/

74

73

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

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

76

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

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unlinkat() */

78

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

75

setgid(), pause(), _exit() */

76

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

79

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

80

78

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

81

79

argp_state, struct argp,

93

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argz_delete(), argz_append(),

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92

argz_stringify(), argz_add(),

95

93

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

94

99

95

#ifdef __linux__

100

96

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

142

138

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

143

139

char *connect_to = NULL;

144

140

const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

146

141

uid_t uid = 65534;

147

142

gid_t gid = 65534;

148

143

159

154

160

155

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

161

156

typedef struct {

157

AvahiSimplePoll *simple_poll;

162

158

AvahiServer *server;

163

159

gnutls_certificate_credentials_t cred;

164

160

unsigned int dh_bits;

166

162

const char *priority;

167

163

gpgme_ctx_t ctx;

168

164

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

165

} mandos_context;

172

166

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

167

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

168

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

169

.dh_bits = 1024, .priority = "SECURE256"

170

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

171

.current_server = NULL };

175

172

176

173

sig_atomic_t quit_now = 0;

177

174

int signal_received = 0;

185

182

perror(print_text);

186

183

}

187

184

188

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

185

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

189

186

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

190

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va_list ap;

191

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va_start (ap, format);

192

189

193

190

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

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191

program_invocation_short_name));

195

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

192

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

196

193

}

197

194

198

195

/*

200

197

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

201

198

* "buffer_length" is how much is already used.

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199

*/

203

__attribute__((nonnull, warn_unused_result))

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200

size_t incbuffer(char **buffer, size_t buffer_length,

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201

size_t buffer_capacity){

206

202

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;

203

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

204

if(buffer == NULL){

213

205

return 0;

214

206

}

215

*buffer = new_buf;

216

207

buffer_capacity += BUFFER_SIZE;

217

208

}

218

209

return buffer_capacity;

219

210

}

220

211

221

212

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

222

__attribute__((nonnull, warn_unused_result))

223

213

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

224

int af, server **current_server){

214

int af){

225

215

int ret;

226

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

227

217

if(new_server == NULL){

234

224

.af = af };

235

225

if(new_server->ip == NULL){

236

226

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

227

return false;

253

228

}

254

229

/* Special case of first server */

255

if(*current_server == NULL){

230

if (mc.current_server == NULL){

256

231

new_server->next = new_server;

257

232

new_server->prev = new_server;

258

*current_server = new_server;

233

mc.current_server = new_server;

234

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

259

235

} else {

260

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

261

new_server->next = *current_server;

262

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

236

new_server->next = mc.current_server;

237

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

263

238

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

239

mc.current_server->prev = new_server;

240

}

241

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

242

if(ret == -1){

243

perror_plus("clock_gettime");

244

return false;

265

245

}

266

246

return true;

267

247

}

269

249

/*

270

250

* Initialize GPGME.

271

251

*/

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){

252

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

253

const char *tempdir){

277

254

gpgme_error_t rc;

278

255

gpgme_engine_info_t engine_info;

279

256

257

280

258

/*

281

259

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

282

260

*/

283

bool import_key(const char * const filename){

261

bool import_key(const char *filename){

284

262

int ret;

285

263

int fd;

286

264

gpgme_data_t pgp_data;

298

276

return false;

299

277

}

300

278

301

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

279

rc = gpgme_op_import(mc.ctx, pgp_data);

302

280

if(rc != GPG_ERR_NO_ERROR){

303

281

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

304

282

gpgme_strsource(rc), gpgme_strerror(rc));

348

326

}

349

327

350

328

/* Create new GPGME "context" */

351

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

329

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

352

330

if(rc != GPG_ERR_NO_ERROR){

353

331

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

354

332

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

367

345

* Decrypt OpenPGP data.

368

346

* Returns -1 on error

369

347

*/

370

__attribute__((nonnull, warn_unused_result))

371

348

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

349

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

350

char **plaintext){

375

351

gpgme_data_t dh_crypto, dh_plain;

376

352

gpgme_error_t rc;

377

353

ssize_t ret;

403

379

404

380

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

405

381

data buffer */

406

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

382

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

407

383

if(rc != GPG_ERR_NO_ERROR){

408

384

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

409

385

gpgme_strsource(rc), gpgme_strerror(rc));

410

386

plaintext_length = -1;

411

387

if(debug){

412

388

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

389

result = gpgme_op_decrypt_result(mc.ctx);

414

390

if(result == NULL){

415

391

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

416

392

} else {

493

469

return plaintext_length;

494

470

}

495

471

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

472

static const char * safer_gnutls_strerror(int value){

498

473

const char *ret = gnutls_strerror(value);

499

474

if(ret == NULL)

500

475

ret = "(unknown)";

502

477

}

503

478

504

479

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

480

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

507

481

const char* string){

508

482

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

509

483

}

510

484

511

__attribute__((nonnull, warn_unused_result))

512

485

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

486

const char *seckeyfilename){

515

487

int ret;

516

488

517

489

if(debug){

534

506

}

535

507

536

508

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

509

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

510

if(ret != GNUTLS_E_SUCCESS){

539

511

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

540

512

safer_gnutls_strerror(ret));

550

522

}

551

523

552

524

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

525

(mc.cred, pubkeyfilename, seckeyfilename,

554

526

GNUTLS_OPENPGP_FMT_BASE64);

555

527

if(ret != GNUTLS_E_SUCCESS){

556

528

fprintf_plus(stderr,

562

534

}

563

535

564

536

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

537

ret = gnutls_dh_params_init(&mc.dh_params);

566

538

if(ret != GNUTLS_E_SUCCESS){

567

539

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

540

" initialization: %s\n",

569

541

safer_gnutls_strerror(ret));

570

542

goto globalfail;

571

543

}

572

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

544

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

573

545

if(ret != GNUTLS_E_SUCCESS){

574

546

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

575

547

safer_gnutls_strerror(ret));

576

548

goto globalfail;

577

549

}

578

550

579

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

551

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

552

581

553

return 0;

582

554

583

555

globalfail:

584

556

585

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_certificate_free_credentials(mc.cred);

586

558

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

559

gnutls_dh_params_deinit(mc.dh_params);

588

560

return -1;

589

561

}

590

562

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

563

static int init_gnutls_session(gnutls_session_t *session){

594

564

int ret;

595

565

/* GnuTLS session creation */

596

566

do {

608

578

{

609

579

const char *err;

610

580

do {

611

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

581

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

612

582

if(quit_now){

613

583

gnutls_deinit(*session);

614

584

return -1;

625

595

626

596

do {

627

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

598

mc.cred);

629

599

if(quit_now){

630

600

gnutls_deinit(*session);

631

601

return -1;

641

611

/* ignore client certificate if any. */

642

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

613

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

615

646

616

return 0;

647

617

}

651

621

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

652

622

653

623

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

655

624

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

656

625

AvahiIfIndex if_index,

657

int af, mandos_context *mc){

626

int af){

658

627

int ret, tcp_sd = -1;

659

628

ssize_t sret;

660

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

661

633

char *buffer = NULL;

662

634

char *decrypted_buffer = NULL;

663

635

size_t buffer_length = 0;

687

659

return -1;

688

660

}

689

661

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);

662

ret = init_gnutls_session(&session);

723

663

if(ret != 0){

724

664

return -1;

725

665

}

744

684

745

685

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

746

686

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);

687

to.in6.sin6_family = (sa_family_t)af;

688

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

749

689

} 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);

690

to.in.sin_family = (sa_family_t)af;

691

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

752

692

}

753

693

if(ret < 0 ){

754

694

int e = errno;

763

703

goto mandos_end;

764

704

}

765

705

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)){

706

to.in6.sin6_port = htons(port);

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

708

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

709

-Wunreachable-code*/

769

710

if(if_index == AVAHI_IF_UNSPEC){

770

711

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

771

712

" incomplete without a network interface\n");

773

714

goto mandos_end;

774

715

}

775

716

/* Set the network interface number as scope */

776

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

717

to.in6.sin6_scope_id = (uint32_t)if_index;

777

718

}

778

719

} else {

779

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

720

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

721

-Wconversion and

722

-Wunreachable-code */

780

723

}

781

724

782

725

if(quit_now){

799

742

}

800

743

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

801

744

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

745

const char *pcret;

802

746

if(af == AF_INET6){

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

747

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

748

sizeof(addrstr));

807

749

} else {

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

750

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

751

sizeof(addrstr));

812

752

}

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);

753

if(pcret == NULL){

754

perror_plus("inet_ntop");

755

} else {

756

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

757

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

758

}

819

759

}

820

760

}

821

761

825

765

}

826

766

827

767

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

768

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

830

769

} else {

831

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

832

sizeof(struct sockaddr_in));

770

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

833

771

}

834

772

if(ret < 0){

835

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

773

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

836

774

int e = errno;

837

775

perror_plus("connect");

838

776

errno = e;

999

937

if(buffer_length > 0){

1000

938

ssize_t decrypted_buffer_size;

1001

939

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1002

&decrypted_buffer, mc);

940

&decrypted_buffer);

1003

941

if(decrypted_buffer_size >= 0){

1004

942

1005

943

written = 0;

1053

991

return retval;

1054

992

}

1055

993

1056

__attribute__((nonnull))

1057

994

static void resolve_callback(AvahiSServiceResolver *r,

1058

995

AvahiIfIndex interface,

1059

996

AvahiProtocol proto,

1067

1004

AVAHI_GCC_UNUSED AvahiStringList *txt,

1068

1005

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1069

1006

flags,

1070

void *mc){

1007

AVAHI_GCC_UNUSED void* userdata){

1071

1008

if(r == NULL){

1072

1009

return;

1073

1010

}

1076

1013

timed out */

1077

1014

1078

1015

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1080

1016

return;

1081

1017

}

1082

1018

1086

1022

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

1087

1023

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

1088

1024

domain,

1089

avahi_strerror(avahi_server_errno

1090

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

1025

avahi_strerror(avahi_server_errno(mc.server)));

1091

1026

break;

1092

1027

1093

1028

case AVAHI_RESOLVER_FOUND:

1101

1036

}

1102

1037

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

1103

1038

interface,

1104

avahi_proto_to_af(proto),

1105

mc);

1039

avahi_proto_to_af(proto));

1106

1040

if(ret == 0){

1107

avahi_simple_poll_quit(simple_poll);

1041

avahi_simple_poll_quit(mc.simple_poll);

1108

1042

} else {

1109

1043

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

1110

avahi_proto_to_af(proto),

1111

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

1044

avahi_proto_to_af(proto))){

1112

1045

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

1113

1046

" list\n", name);

1114

1047

}

1127

1060

const char *domain,

1128

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1129

1062

flags,

1130

void *mc){

1063

AVAHI_GCC_UNUSED void* userdata){

1131

1064

if(b == NULL){

1132

1065

return;

1133

1066

}

1144

1077

case AVAHI_BROWSER_FAILURE:

1145

1078

1146

1079

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);

1080

avahi_strerror(avahi_server_errno(mc.server)));

1081

avahi_simple_poll_quit(mc.simple_poll);

1150

1082

return;

1151

1083

1152

1084

case AVAHI_BROWSER_NEW:

1155

1087

the callback function is called the Avahi server will free the

1156

1088

resolver for us. */

1157

1089

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)

1090

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

1091

name, type, domain, protocol, 0,

1092

resolve_callback, NULL) == NULL)

1162

1093

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

1163

1094

" %s\n", name,

1164

avahi_strerror(avahi_server_errno

1165

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

1095

avahi_strerror(avahi_server_errno(mc.server)));

1166

1096

break;

1167

1097

1168

1098

case AVAHI_BROWSER_REMOVE:

1187

1117

signal_received = sig;

1188

1118

int old_errno = errno;

1189

1119

/* set main loop to exit */

1190

if(simple_poll != NULL){

1191

avahi_simple_poll_quit(simple_poll);

1120

if(mc.simple_poll != NULL){

1121

avahi_simple_poll_quit(mc.simple_poll);

1192

1122

}

1193

1123

errno = old_errno;

1194

1124

}

1195

1125

1196

__attribute__((nonnull, warn_unused_result))

1197

1126

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

1198

1127

int ret;

1199

1128

error_t ret_errno;

1218

1147

return true;

1219

1148

}

1220

1149

1221

__attribute__((nonnull, warn_unused_result))

1222

1150

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

1223

1151

1224

1152

/* Reject the loopback device */

1266

1194

* corresponds to an acceptable network device.

1267

1195

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

1268

1196

*/

1269

__attribute__((nonnull, warn_unused_result))

1270

1197

int good_interface(const struct dirent *if_entry){

1271

1198

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

1272

1199

return 0;

1290

1217

/*

1291

1218

* This function determines if a network interface is up.

1292

1219

*/

1293

__attribute__((nonnull, warn_unused_result))

1294

1220

bool interface_is_up(const char *interface){

1295

1221

struct ifreq ifr;

1296

1222

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

1307

1233

/*

1308

1234

* This function determines if a network interface is running

1309

1235

*/

1310

__attribute__((nonnull, warn_unused_result))

1311

1236

bool interface_is_running(const char *interface){

1312

1237

struct ifreq ifr;

1313

1238

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

1321

1246

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

1322

1247

}

1323

1248

1324

__attribute__((nonnull, pure, warn_unused_result))

1325

1249

int notdotentries(const struct dirent *direntry){

1326

1250

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

1327

1251

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

1334

1258

}

1335

1259

1336

1260

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

1337

__attribute__((nonnull, warn_unused_result))

1338

1261

int runnable_hook(const struct dirent *direntry){

1339

1262

int ret;

1340

1263

size_t sret;

1348

1271

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

1349

1272

"abcdefghijklmnopqrstuvwxyz"

1350

1273

"0123456789"

1351

"_.-");

1274

"_-");

1352

1275

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

1353

1276

/* Contains non-allowed characters */

1354

1277

if(debug){

1358

1281

return 0;

1359

1282

}

1360

1283

1361

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

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1362

1292

if(ret == -1){

1363

1293

if(debug){

1364

1294

perror_plus("Could not stat hook");

1388

1318

return 1;

1389

1319

}

1390

1320

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1394

1322

int ret;

1395

1323

struct timespec now;

1396

1324

struct timespec waited_time;

1397

1325

intmax_t block_time;

1398

1326

1399

1327

while(true){

1400

if(mc->current_server == NULL){

1401

if(debug){

1328

if(mc.current_server == NULL){

1329

if (debug){

1402

1330

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

1403

1331

" No timeout!\n");

1404

1332

}

1405

1333

ret = avahi_simple_poll_iterate(s, -1);

1406

1334

} else {

1407

if(debug){

1335

if (debug){

1408

1336

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

1409

1337

" it, or wait\n");

1410

1338

}

1417

1345

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

1418

1346

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

1419

1347

waited_time.tv_sec = (now.tv_sec

1420

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

1348

- mc.current_server->last_seen.tv_sec);

1421

1349

waited_time.tv_nsec = (now.tv_nsec

1422

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

1350

- mc.current_server->last_seen.tv_nsec);

1423

1351

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

1424

1352

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

1425

1353

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

1427

1355

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

1428

1356

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

1429

1357

1430

if(debug){

1358

if (debug){

1431

1359

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

1432

1360

block_time);

1433

1361

}

1434

1362

1435

1363

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);

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1440

1368

if(ret == 0){

1441

avahi_simple_poll_quit(s);

1369

avahi_simple_poll_quit(mc.simple_poll);

1442

1370

return 0;

1443

1371

}

1444

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1445

&mc->current_server->last_seen);

1373

&mc.current_server->last_seen);

1446

1374

if(ret == -1){

1447

1375

perror_plus("clock_gettime");

1448

1376

return -1;

1449

1377

}

1450

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

1378

mc.current_server = mc.current_server->next;

1451

1379

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

1452

1380

servers, but don't block */

1453

1381

}

1455

1383

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

1456

1384

}

1457

1385

if(ret != 0){

1458

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

1386

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

1459

1387

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

1460

1388

}

1461

1389

}

1463

1391

}

1464

1392

1465

1393

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

1466

__attribute__((warn_unused_result))

1467

1394

error_t raise_privileges(void){

1468

1395

error_t old_errno = errno;

1469

1396

error_t ret_errno = 0;

1470

1397

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

1471

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1472

1400

}

1473

1401

errno = old_errno;

1474

1402

return ret_errno;

1475

1403

}

1476

1404

1477

1405

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

1478

__attribute__((warn_unused_result))

1479

1406

error_t raise_privileges_permanently(void){

1480

1407

error_t old_errno = errno;

1481

1408

error_t ret_errno = raise_privileges();

1485

1412

}

1486

1413

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

1487

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1488

1416

}

1489

1417

errno = old_errno;

1490

1418

return ret_errno;

1491

1419

}

1492

1420

1493

1421

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

1494

__attribute__((warn_unused_result))

1495

1422

error_t lower_privileges(void){

1496

1423

error_t old_errno = errno;

1497

1424

error_t ret_errno = 0;

1498

1425

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

1499

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1500

1428

}

1501

1429

errno = old_errno;

1502

1430

return ret_errno;

1503

1431

}

1504

1432

1505

1433

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1507

1434

error_t lower_privileges_permanently(void){

1508

1435

error_t old_errno = errno;

1509

1436

error_t ret_errno = 0;

1510

1437

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

1511

1438

ret_errno = errno;

1439

perror_plus("setuid");

1512

1440

}

1513

1441

errno = old_errno;

1514

1442

return ret_errno;

1515

1443

}

1516

1444

1517

__attribute__((nonnull))

1518

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

1445

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

1519

1446

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__ */

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1547

1452

if(numhooks == -1){

1548

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);

1453

if(errno == ENOENT){

1454

if(debug){

1455

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

1456

" found\n", hookdir);

1457

}

1458

} else {

1459

perror_plus("scandir");

1559

1460

}

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){

1461

} else {

1462

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

1463

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

1464

direntry = direntries[i];

1465

char *fullname = NULL;

1466

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

1467

if(ret < 0){

1621

1468

perror_plus("asprintf");

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

if(ret == -1){

1469

continue;

1470

}

1471

if(debug){

1472

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

1473

direntry->d_name);

1474

}

1475

pid_t hook_pid = fork();

1476

if(hook_pid == 0){

1477

/* Child */

1478

/* Raise privileges */

1479

raise_privileges_permanently();

1480

/* Set group */

1481

errno = 0;

1482

ret = setgid(0);

1483

if(ret == -1){

1484

perror_plus("setgid");

1485

}

1486

/* Reset supplementary groups */

1487

errno = 0;

1488

ret = setgroups(0, NULL);

1489

if(ret == -1){

1490

perror_plus("setgroups");

1491

}

1492

dup2(devnull, STDIN_FILENO);

1493

close(devnull);

1494

dup2(STDERR_FILENO, STDOUT_FILENO);

1495

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

1496

if(ret == -1){

1497

perror_plus("setenv");

1498

_exit(EX_OSERR);

1499

}

1500

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

1501

if(ret == -1){

1502

perror_plus("setenv");

1503

_exit(EX_OSERR);

1504

}

1505

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

1506

if(ret == -1){

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

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

1511

if(ret == -1){

1512

perror_plus("setenv");

1513

_exit(EX_OSERR);

1514

}

1515

char *delaystring;

1516

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

1517

if(ret == -1){

1518

perror_plus("asprintf");

1519

_exit(EX_OSERR);

1520

}

1521

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

1522

if(ret == -1){

1523

free(delaystring);

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1626

1527

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

int status;

1654

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

1655

perror_plus("waitpid");

1656

free(direntry);

1657

continue;

1658

}

1659

if(WIFEXITED(status)){

1660

if(WEXITSTATUS(status) != 0){

1661

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

1662

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

1663

WEXITSTATUS(status));

1664

free(direntry);

1665

continue;

1666

}

1667

} else if(WIFSIGNALED(status)){

1668

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

1669

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

1670

WTERMSIG(status));

1671

free(direntry);

1672

continue;

1528

if(connect_to != NULL){

1529

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

1530

if(ret == -1){

1531

perror_plus("setenv");

1532

_exit(EX_OSERR);

1533

}

1534

}

1535

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1536

perror_plus("execl");

1537

_exit(EXIT_FAILURE);

1538

}

1673

1539

} else {

1674

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

1675

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

1676

free(direntry);

1677

continue;

1678

}

1679

}

1680

if(debug){

1681

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

1682

direntry->d_name);

1683

}

1684

free(direntry);

1685

}

1686

free(direntries);

1687

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

1688

perror_plus("close");

1689

} else {

1690

hookdir_fd = -1;

1691

}

1692

close(devnull);

1540

int status;

1541

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

1542

perror_plus("waitpid");

1543

free(fullname);

1544

continue;

1545

}

1546

if(WIFEXITED(status)){

1547

if(WEXITSTATUS(status) != 0){

1548

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

1549

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

1550

WEXITSTATUS(status));

1551

free(fullname);

1552

continue;

1553

}

1554

} else if(WIFSIGNALED(status)){

1555

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

1556

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

1557

WTERMSIG(status));

1558

free(fullname);

1559

continue;

1560

} else {

1561

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

1562

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

1563

free(fullname);

1564

continue;

1565

}

1566

}

1567

free(fullname);

1568

if(debug){

1569

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

1570

direntry->d_name);

1571

}

1572

}

1573

close(devnull);

1574

}

1575

return true;

1693

1576

}

1694

1577

1695

__attribute__((nonnull, warn_unused_result))

1696

1578

error_t bring_up_interface(const char *const interface,

1697

1579

const float delay){

1580

int sd = -1;

1698

1581

error_t old_errno = errno;

1699

int ret;

1582

error_t ret_errno = 0;

1583

int ret, ret_setflags;

1700

1584

struct ifreq network;

1701

1585

unsigned int if_index = if_nametoindex(interface);

1702

1586

if(if_index == 0){

1711

1595

}

1712

1596

1713

1597

if(not interface_is_up(interface)){

1714

error_t ret_errno = 0, ioctl_errno = 0;

1715

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

1598

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

1716

1599

ret_errno = errno;

1717

1600

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

1718

1601

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

1719

errno = old_errno;

1720

1602

return ret_errno;

1721

1603

}

1722

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

1604

network.ifr_flags |= IFF_UP;

1723

1605

1724

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

1725

if(sd == -1){

1606

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1607

if(sd < 0){

1726

1608

ret_errno = errno;

1727

1609

perror_plus("socket");

1728

1610

errno = old_errno;

1729

1611

return ret_errno;

1730

1612

}

1731

1613

1732

1614

if(quit_now){

1733

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

1734

if(ret == -1){

1735

perror_plus("close");

1736

}

1615

close(sd);

1737

1616

errno = old_errno;

1738

1617

return EINTR;

1739

1618

}

1743

1622

interface);

1744

1623

}

1745

1624

1746

/* Raise privileges */

1747

ret_errno = raise_privileges();

1748

if(ret_errno != 0){

1749

errno = ret_errno;

1750

perror_plus("Failed to raise privileges");

1751

}

1625

/* Raise priviliges */

1626

raise_privileges();

1752

1627

1753

1628

#ifdef __linux__

1754

int ret_linux;

1755

bool restore_loglevel = false;

1756

if(ret_errno == 0){

1757

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1758

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

1759

ret_linux = klogctl(8, NULL, 5);

1760

if(ret_linux == -1){

1761

perror_plus("klogctl");

1762

} else {

1763

restore_loglevel = true;

1764

}

1629

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1630

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

1631

int ret_linux = klogctl(8, NULL, 5);

1632

bool restore_loglevel = true;

1633

if(ret_linux == -1){

1634

restore_loglevel = false;

1635

perror_plus("klogctl");

1765

1636

}

1766

1637

#endif /* __linux__ */

1767

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

1768

ioctl_errno = errno;

1638

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

1639

ret_errno = errno;

1769

1640

#ifdef __linux__

1770

1641

if(restore_loglevel){

1771

1642

ret_linux = klogctl(7, NULL, 0);

1775

1646

}

1776

1647

#endif /* __linux__ */

1777

1648

1778

/* If raise_privileges() succeeded above */

1779

if(ret_errno == 0){

1780

/* Lower privileges */

1781

ret_errno = lower_privileges();

1782

if(ret_errno != 0){

1783

errno = ret_errno;

1784

perror_plus("Failed to lower privileges");

1785

}

1786

}

1649

/* Lower privileges */

1650

lower_privileges();

1787

1651

1788

1652

/* Close the socket */

1789

1653

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

1792

1656

}

1793

1657

1794

1658

if(ret_setflags == -1){

1795

errno = ioctl_errno;

1659

errno = ret_errno;

1796

1660

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1797

1661

errno = old_errno;

1798

return ioctl_errno;

1662

return ret_errno;

1799

1663

}

1800

1664

} else if(debug){

1801

1665

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

1819

1683

return 0;

1820

1684

}

1821

1685

1822

__attribute__((nonnull, warn_unused_result))

1823

1686

error_t take_down_interface(const char *const interface){

1687

int sd = -1;

1824

1688

error_t old_errno = errno;

1689

error_t ret_errno = 0;

1690

int ret, ret_setflags;

1825

1691

struct ifreq network;

1826

1692

unsigned int if_index = if_nametoindex(interface);

1827

1693

if(if_index == 0){

1830

1696

return ENXIO;

1831

1697

}

1832

1698

if(interface_is_up(interface)){

1833

error_t ret_errno = 0, ioctl_errno = 0;

1834

1699

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

1835

1700

ret_errno = errno;

1836

1701

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

1837

1702

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

1838

errno = old_errno;

1839

1703

return ret_errno;

1840

1704

}

1841

1705

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

1842

1706

1843

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

1844

if(sd == -1){

1707

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1708

if(sd < 0){

1845

1709

ret_errno = errno;

1846

1710

perror_plus("socket");

1847

1711

errno = old_errno;

1853

1717

interface);

1854

1718

}

1855

1719

1856

/* Raise privileges */

1857

ret_errno = raise_privileges();

1858

if(ret_errno != 0){

1859

errno = ret_errno;

1860

perror_plus("Failed to raise privileges");

1861

}

1862

1863

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

1864

ioctl_errno = errno;

1865

1866

/* If raise_privileges() succeeded above */

1867

if(ret_errno == 0){

1868

/* Lower privileges */

1869

ret_errno = lower_privileges();

1870

if(ret_errno != 0){

1871

errno = ret_errno;

1872

perror_plus("Failed to lower privileges");

1873

}

1874

}

1720

/* Raise priviliges */

1721

raise_privileges();

1722

1723

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

1724

ret_errno = errno;

1725

1726

/* Lower privileges */

1727

lower_privileges();

1875

1728

1876

1729

/* Close the socket */

1877

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

1730

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

1878

1731

if(ret == -1){

1879

1732

perror_plus("close");

1880

1733

}

1881

1734

1882

1735

if(ret_setflags == -1){

1883

errno = ioctl_errno;

1736

errno = ret_errno;

1884

1737

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1885

1738

errno = old_errno;

1886

return ioctl_errno;

1739

return ret_errno;

1887

1740

}

1888

1741

} else if(debug){

1889

1742

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

1895

1748

}

1896

1749

1897

1750

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

1898

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

1899

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

1900

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

1901

.interfaces = NULL, .interfaces_size = 0 };

1902

1751

AvahiSServiceBrowser *sb = NULL;

1903

1752

error_t ret_errno;

1904

1753

int ret;

1905

1754

intmax_t tmpmax;

1906

1755

char *tmp;

1907

1756

int exitcode = EXIT_SUCCESS;

1757

char *interfaces = NULL;

1758

size_t interfaces_size = 0;

1908

1759

char *interfaces_to_take_down = NULL;

1909

1760

size_t interfaces_to_take_down_size = 0;

1910

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

1911

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

1912

char *tempdir = NULL;

1761

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

1762

bool tempdir_created = false;

1913

1763

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1914

1764

const char *seckey = PATHDIR "/" SECKEY;

1915

1765

const char *pubkey = PATHDIR "/" PUBKEY;

1916

1766

char *interfaces_hooks = NULL;

1767

size_t interfaces_hooks_size = 0;

1917

1768

1918

1769

bool gnutls_initialized = false;

1919

1770

bool gpgme_initialized = false;

2010

1861

connect_to = arg;

2011

1862

break;

2012

1863

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

2013

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

2014

arg, (int)',');

1864

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1865

(int)',');

2015

1866

if(ret_errno != 0){

2016

1867

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

2017

1868

}

2097

1948

/* Work around Debian bug #633582:

2098

1949

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

2099

1950

2100

/* Re-raise privileges */

2101

ret_errno = raise_privileges();

2102

if(ret_errno != 0){

2103

errno = ret_errno;

2104

perror_plus("Failed to raise privileges");

2105

} else {

1951

/* Re-raise priviliges */

1952

if(raise_privileges() == 0){

2106

1953

struct stat st;

2107

1954

2108

1955

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

2148

1995

}

2149

1996

2150

1997

/* Lower privileges */

2151

ret_errno = lower_privileges();

2152

if(ret_errno != 0){

2153

errno = ret_errno;

2154

perror_plus("Failed to lower privileges");

1998

errno = 0;

1999

ret = seteuid(uid);

2000

if(ret == -1){

2001

perror_plus("seteuid");

2155

2002

}

2156

2003

}

2157

2004

}

2158

2005

2159

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

2006

/* Remove empty interface names */

2160

2007

{

2161

2008

char *interface = NULL;

2162

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

2009

while((interface = argz_next(interfaces, interfaces_size,

2163

2010

interface))){

2164

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

2165

and if_nametoindex(interface) == 0){

2166

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

2011

if(if_nametoindex(interface) == 0){

2012

if(interface[0] != '\0' and strcmp(interface, "none") != 0){

2167

2013

fprintf_plus(stderr, "Not using nonexisting interface"

2168

2014

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

2169

2015

}

2170

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

2016

argz_delete(&interfaces, &interfaces_size, interface);

2171

2017

interface = NULL;

2172

2018

}

2173

2019

}

2175

2021

2176

2022

/* Run network hooks */

2177

2023

{

2178

if(mc.interfaces != NULL){

2179

interfaces_hooks = malloc(mc.interfaces_size);

2024

2025

if(interfaces != NULL){

2026

interfaces_hooks = malloc(interfaces_size);

2180

2027

if(interfaces_hooks == NULL){

2181

2028

perror_plus("malloc");

2182

2029

goto end;

2183

2030

}

2184

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

2185

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

2186

}

2187

run_network_hooks("start", interfaces_hooks != NULL ?

2188

interfaces_hooks : "", delay);

2031

memcpy(interfaces_hooks, interfaces, interfaces_size);

2032

interfaces_hooks_size = interfaces_size;

2033

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2034

(int)',');

2035

}

2036

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2037

interfaces_hooks : "", delay)){

2038

goto end;

2039

}

2189

2040

}

2190

2041

2191

2042

if(not debug){

2196

2047

from the signal handler */

2197

2048

/* Initialize the pseudo-RNG for Avahi */

2198

2049

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

2199

simple_poll = avahi_simple_poll_new();

2200

if(simple_poll == NULL){

2050

mc.simple_poll = avahi_simple_poll_new();

2051

if(mc.simple_poll == NULL){

2201

2052

fprintf_plus(stderr,

2202

2053

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

2203

2054

exitcode = EX_UNAVAILABLE;

2268

2119

}

2269

2120

2270

2121

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

2271

if(mc.interfaces == NULL){

2272

struct dirent **direntries = NULL;

2122

if(interfaces == NULL){

2123

struct dirent **direntries;

2273

2124

/* Look for any good interfaces */

2274

2125

ret = scandir(sys_class_net, &direntries, good_interface,

2275

2126

alphasort);

2276

2127

if(ret >= 1){

2277

2128

/* Add all found interfaces to interfaces list */

2278

2129

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

2279

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

2130

ret_errno = argz_add(&interfaces, &interfaces_size,

2280

2131

direntries[i]->d_name);

2281

2132

if(ret_errno != 0){

2282

errno = ret_errno;

2283

2133

perror_plus("argz_add");

2284

free(direntries[i]);

2285

2134

continue;

2286

2135

}

2287

2136

if(debug){

2288

2137

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

2289

2138

direntries[i]->d_name);

2290

2139

}

2291

free(direntries[i]);

2292

2140

}

2293

2141

free(direntries);

2294

2142

} else {

2295

if(ret == 0){

2296

free(direntries);

2297

}

2143

free(direntries);

2298

2144

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

2299

2145

exitcode = EXIT_FAILURE;

2300

2146

goto end;

2301

2147

}

2302

2148

}

2303

2149

2304

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

2305

{

2150

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

2151

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

2152

if(debug){

2153

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

2154

interfaces);

2155

}

2156

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2157

}

2158

2159

/* Bring up interfaces which are down */

2160

if(not (argz_count(interfaces, interfaces_size) == 1

2161

and strcmp(interfaces, "none") == 0)){

2306

2162

char *interface = NULL;

2307

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

2163

while((interface = argz_next(interfaces, interfaces_size,

2308

2164

interface))){

2309

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

2310

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

2311

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

2312

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

2313

interface);

2314

interface = NULL;

2315

while((interface = argz_next(mc.interfaces,

2316

mc.interfaces_size, interface))){

2317

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

2318

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

2319

interface);

2320

interface = NULL;

2321

}

2322

}

2323

break;

2324

}

2325

2165

bool interface_was_up = interface_is_up(interface);

2326

errno = bring_up_interface(interface, delay);

2166

ret = bring_up_interface(interface, delay);

2327

2167

if(not interface_was_up){

2328

if(errno != 0){

2168

if(ret != 0){

2169

errno = ret;

2329

2170

perror_plus("Failed to bring up interface");

2330

2171

} else {

2331

errno = argz_add(&interfaces_to_take_down,

2332

&interfaces_to_take_down_size,

2333

interface);

2334

if(errno != 0){

2335

perror_plus("argz_add");

2336

}

2172

ret_errno = argz_add(&interfaces_to_take_down,

2173

&interfaces_to_take_down_size,

2174

interface);

2337

2175

}

2338

2176

}

2339

2177

}

2178

free(interfaces);

2179

interfaces = NULL;

2180

interfaces_size = 0;

2340

2181

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

2341

2182

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

2342

2183

}

2343

2184

}

2344

2185

2345

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

2346

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

2347

if(debug){

2348

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

2349

mc.interfaces);

2350

}

2351

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

2352

}

2353

2354

2186

if(quit_now){

2355

2187

goto end;

2356

2188

}

2357

2189

2358

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

2190

ret = init_gnutls_global(pubkey, seckey);

2359

2191

if(ret == -1){

2360

2192

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

2361

2193

exitcode = EX_UNAVAILABLE;

2368

2200

goto end;

2369

2201

}

2370

2202

2371

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

2372

tempdir = mkdtemp(run_tempdir);

2373

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

2374

if(debug){

2375

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

2376

run_tempdir, old_tempdir);

2377

}

2378

tempdir = mkdtemp(old_tempdir);

2379

}

2380

if(tempdir == NULL){

2203

if(mkdtemp(tempdir) == NULL){

2381

2204

perror_plus("mkdtemp");

2382

2205

goto end;

2383

2206

}

2207

tempdir_created = true;

2384

2208

2385

2209

if(quit_now){

2386

2210

goto end;

2387

2211

}

2388

2212

2389

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

2213

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

2390

2214

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

2391

2215

exitcode = EX_UNAVAILABLE;

2392

2216

goto end;

2422

2246

exitcode = EX_USAGE;

2423

2247

goto end;

2424

2248

}

2425

2249

2426

2250

if(quit_now){

2427

2251

goto end;

2428

2252

}

2449

2273

}

2450

2274

2451

2275

while(not quit_now){

2452

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

2453

&mc);

2276

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

2454

2277

if(quit_now or ret == 0){

2455

2278

break;

2456

2279

}

2458

2281

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

2459

2282

(int)retry_interval);

2460

2283

}

2461

sleep((unsigned int)retry_interval);

2284

sleep((int)retry_interval);

2462

2285

}

2463

2286

2464

if(not quit_now){

2287

if (not quit_now){

2465

2288

exitcode = EXIT_SUCCESS;

2466

2289

}

2467

2290

2482

2305

config.publish_domain = 0;

2483

2306

2484

2307

/* Allocate a new server */

2485

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2486

&config, NULL, NULL, &ret_errno);

2308

mc.server = avahi_server_new(avahi_simple_poll_get

2309

(mc.simple_poll), &config, NULL,

2310

NULL, &ret_errno);

2487

2311

2488

2312

/* Free the Avahi configuration data */

2489

2313

avahi_server_config_free(&config);

2504

2328

/* Create the Avahi service browser */

2505

2329

sb = avahi_s_service_browser_new(mc.server, if_index,

2506

2330

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2507

NULL, 0, browse_callback,

2508

(void *)&mc);

2331

NULL, 0, browse_callback, NULL);

2509

2332

if(sb == NULL){

2510

2333

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

2511

2334

avahi_strerror(avahi_server_errno(mc.server)));

2522

2345

if(debug){

2523

2346

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

2524

2347

}

2525

2526

ret = avahi_loop_with_timeout(simple_poll,

2527

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

2348

2349

ret = avahi_loop_with_timeout(mc.simple_poll,

2350

(int)(retry_interval * 1000));

2528

2351

if(debug){

2529

2352

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

2530

2353

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

2537

2360

}

2538

2361

2539

2362

/* Cleanup things */

2540

free(mc.interfaces);

2541

2542

2363

if(sb != NULL)

2543

2364

avahi_s_service_browser_free(sb);

2544

2365

2545

2366

if(mc.server != NULL)

2546

2367

avahi_server_free(mc.server);

2547

2368

2548

if(simple_poll != NULL)

2549

avahi_simple_poll_free(simple_poll);

2369

if(mc.simple_poll != NULL)

2370

avahi_simple_poll_free(mc.simple_poll);

2550

2371

2551

2372

if(gnutls_initialized){

2552

2373

gnutls_certificate_free_credentials(mc.cred);

2564

2385

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

2565

2386

while(mc.current_server != NULL){

2566

2387

server *next = mc.current_server->next;

2567

#ifdef __GNUC__

2568

#pragma GCC diagnostic push

2569

#pragma GCC diagnostic ignored "-Wcast-qual"

2570

#endif

2571

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

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic pop

2574

#endif

2575

2388

free(mc.current_server);

2576

2389

mc.current_server = next;

2577

2390

}

2578

2391

}

2579

2392

2580

/* Re-raise privileges */

2393

/* Re-raise priviliges */

2581

2394

{

2582

ret_errno = raise_privileges();

2583

if(ret_errno != 0){

2584

errno = ret_errno;

2585

perror_plus("Failed to raise privileges");

2586

} else {

2587

2588

/* Run network hooks */

2589

run_network_hooks("stop", interfaces_hooks != NULL ?

2590

interfaces_hooks : "", delay);

2591

2592

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

2593

{

2594

char *interface = NULL;

2595

while((interface=argz_next(interfaces_to_take_down,

2596

interfaces_to_take_down_size,

2597

interface))){

2598

ret_errno = take_down_interface(interface);

2599

if(ret_errno != 0){

2600

errno = ret_errno;

2601

perror_plus("Failed to take down interface");

2602

}

2603

}

2604

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

2605

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

2606

" down\n");

2607

}

2608

}

2609

}

2610

2611

ret_errno = lower_privileges_permanently();

2612

if(ret_errno != 0){

2613

errno = ret_errno;

2614

perror_plus("Failed to lower privileges permanently");

2615

}

2395

raise_privileges();

2396

2397

/* Run network hooks */

2398

run_network_hooks("stop", interfaces_hooks != NULL ?

2399

interfaces_hooks : "", delay);

2400

2401

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

2402

{

2403

char *interface = NULL;

2404

while((interface=argz_next(interfaces_to_take_down,

2405

interfaces_to_take_down_size,

2406

interface))){

2407

ret_errno = take_down_interface(interface);

2408

if(ret_errno != 0){

2409

errno = ret_errno;

2410

perror_plus("Failed to take down interface");

2411

}

2412

}

2413

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

2414

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

2415

" down\n");

2416

}

2417

}

2418

2419

lower_privileges_permanently();

2616

2420

}

2617

2421

2618

2422

free(interfaces_to_take_down);

2619

2423

free(interfaces_hooks);

2620

2424

2621

2425

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

2622

if(tempdir != NULL){

2426

if(tempdir_created){

2623

2427

struct dirent **direntries = NULL;

2624

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

2625

O_NOFOLLOW));

2626

if(tempdir_fd == -1){

2627

perror_plus("open");

2628

} else {

2629

#ifdef __GLIBC__

2630

#if __GLIBC_PREREQ(2, 15)

2631

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

2632

notdotentries, alphasort);

2633

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

2634

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

2635

alphasort);

2636

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

2637

#else /* not __GLIBC__ */

2638

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

2639

alphasort);

2640

#endif /* not __GLIBC__ */

2641

if(numentries >= 0){

2642

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

2643

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

2644

if(ret == -1){

2645

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

2646

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

2647

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

2648

}

2649

free(direntries[i]);

2650

}

2651

2652

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

2653

free(direntries);

2654

if(numentries == -1){

2655

perror_plus("scandir");

2656

}

2657

ret = rmdir(tempdir);

2658

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

2659

perror_plus("rmdir");

2660

}

2428

struct dirent *direntry = NULL;

2429

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

2430

alphasort);

2431

if (numentries > 0){

2432

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

2433

direntry = direntries[i];

2434

char *fullname = NULL;

2435

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

2436

direntry->d_name);

2437

if(ret < 0){

2438

perror_plus("asprintf");

2439

continue;

2440

}

2441

ret = remove(fullname);

2442

if(ret == -1){

2443

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

2444

strerror(errno));

2445

}

2446

free(fullname);

2661

2447

}

2662

TEMP_FAILURE_RETRY(close(tempdir_fd));

2448

}

2449

2450

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

2451

free(direntries);

2452

if (numentries == -1){

2453

perror_plus("scandir");

2454

}

2455

ret = rmdir(tempdir);

2456

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

2457

perror_plus("rmdir");

2663

2458

}

2664

2459

}

2665

2460