/mandos/release : revision 237.16.18

9

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

10

*

11

* Everything else is

12

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() */

44

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

43

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()

62

61

*/

63

62

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

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63

strtoimax() */

64

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

65

#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(),

76

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

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unlinkat() */

78

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

76

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

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

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80

argp_state, struct argp,

89

88

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

90

89

WEXITSTATUS(), WTERMSIG() */

91

90

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

92

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

93

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

91

99

92

#ifdef __linux__

100

93

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

142

135

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

143

136

char *connect_to = NULL;

144

137

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

148

138

149

139

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

150

140

typedef struct server{

151

141

const char *ip;

152

in_port_t port;

142

uint16_t port;

153

143

AvahiIfIndex if_index;

154

144

int af;

155

145

struct timespec last_seen;

159

149

160

150

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

161

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

162

153

AvahiServer *server;

163

154

gnutls_certificate_credentials_t cred;

164

155

unsigned int dh_bits;

166

157

const char *priority;

167

158

gpgme_ctx_t ctx;

168

159

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

160

} mandos_context;

172

161

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

175

167

176

168

sig_atomic_t quit_now = 0;

177

169

int signal_received = 0;

178

170

179

171

/* Function to use when printing errors */

180

172

void perror_plus(const char *print_text){

181

int e = errno;

182

173

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

183

174

program_invocation_short_name);

184

errno = e;

185

175

perror(print_text);

186

176

}

187

177

188

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

189

178

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

190

179

va_list ap;

191

180

va_start (ap, format);

192

181

193

182

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

194

183

program_invocation_short_name));

195

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

184

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

196

185

}

197

186

198

187

/*

200

189

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

201

190

* "buffer_length" is how much is already used.

202

191

*/

203

__attribute__((nonnull, warn_unused_result))

204

192

size_t incbuffer(char **buffer, size_t buffer_length,

205

193

size_t buffer_capacity){

206

194

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;

195

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

196

if(buffer == NULL){

213

197

return 0;

214

198

}

215

*buffer = new_buf;

216

199

buffer_capacity += BUFFER_SIZE;

217

200

}

218

201

return buffer_capacity;

219

202

}

220

203

221

204

/* 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){

205

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

206

int af){

225

207

int ret;

226

208

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

227

209

if(new_server == NULL){

228

210

perror_plus("malloc");

229

return false;

211

return -1;

230

212

}

231

213

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

232

214

.port = port,

234

216

.af = af };

235

217

if(new_server->ip == NULL){

236

218

perror_plus("strdup");

237

return false;

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

219

return -1;

243

220

}

244

221

/* Special case of first server */

245

if(*current_server == NULL){

222

if (mc.current_server == NULL){

246

223

new_server->next = new_server;

247

224

new_server->prev = new_server;

248

*current_server = new_server;

225

mc.current_server = new_server;

226

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

249

227

} else {

250

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

251

new_server->next = *current_server;

252

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

228

new_server->next = mc.current_server;

229

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

253

230

new_server->prev->next = new_server;

254

(*current_server)->prev = new_server;

255

}

256

return true;

231

mc.current_server->prev = new_server;

232

}

233

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

236

return -1;

237

}

238

return 0;

257

239

}

258

240

259

241

/*

260

242

* Initialize GPGME.

261

243

*/

262

__attribute__((nonnull, warn_unused_result))

263

static bool init_gpgme(const char * const seckey,

264

const char * const pubkey,

265

const char * const tempdir,

266

mandos_context *mc){

244

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

245

const char *tempdir){

267

246

gpgme_error_t rc;

268

247

gpgme_engine_info_t engine_info;

269

248

249

270

250

/*

271

251

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

272

252

*/

273

bool import_key(const char * const filename){

253

bool import_key(const char *filename){

274

254

int ret;

275

255

int fd;

276

256

gpgme_data_t pgp_data;

288

268

return false;

289

269

}

290

270

291

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

271

rc = gpgme_op_import(mc.ctx, pgp_data);

292

272

if(rc != GPG_ERR_NO_ERROR){

293

273

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

294

274

gpgme_strsource(rc), gpgme_strerror(rc));

338

318

}

339

319

340

320

/* Create new GPGME "context" */

341

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

321

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

342

322

if(rc != GPG_ERR_NO_ERROR){

343

323

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

344

324

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

357

337

* Decrypt OpenPGP data.

358

338

* Returns -1 on error

359

339

*/

360

__attribute__((nonnull, warn_unused_result))

361

340

static ssize_t pgp_packet_decrypt(const char *cryptotext,

362

341

size_t crypto_size,

363

char **plaintext,

364

mandos_context *mc){

342

char **plaintext){

365

343

gpgme_data_t dh_crypto, dh_plain;

366

344

gpgme_error_t rc;

367

345

ssize_t ret;

393

371

394

372

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

395

373

data buffer */

396

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

374

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

397

375

if(rc != GPG_ERR_NO_ERROR){

398

376

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

399

377

gpgme_strsource(rc), gpgme_strerror(rc));

400

378

plaintext_length = -1;

401

379

if(debug){

402

380

gpgme_decrypt_result_t result;

403

result = gpgme_op_decrypt_result(mc->ctx);

381

result = gpgme_op_decrypt_result(mc.ctx);

404

382

if(result == NULL){

405

383

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

406

384

} else {

483

461

return plaintext_length;

484

462

}

485

463

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

488

const char *ret = gnutls_strerror(value);

464

static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

489

467

if(ret == NULL)

490

468

ret = "(unknown)";

491

469

return ret;

492

470

}

493

471

494

472

/* GnuTLS log function callback */

495

__attribute__((nonnull))

496

473

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

497

474

const char* string){

498

475

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

499

476

}

500

477

501

__attribute__((nonnull, warn_unused_result))

502

478

static int init_gnutls_global(const char *pubkeyfilename,

503

const char *seckeyfilename,

504

mandos_context *mc){

479

const char *seckeyfilename){

505

480

int ret;

506

481

507

482

if(debug){

524

499

}

525

500

526

501

/* OpenPGP credentials */

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

528

503

if(ret != GNUTLS_E_SUCCESS){

529

504

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

530

505

safer_gnutls_strerror(ret));

540

515

}

541

516

542

517

ret = gnutls_certificate_set_openpgp_key_file

543

(mc->cred, pubkeyfilename, seckeyfilename,

518

(mc.cred, pubkeyfilename, seckeyfilename,

544

519

GNUTLS_OPENPGP_FMT_BASE64);

545

520

if(ret != GNUTLS_E_SUCCESS){

546

521

fprintf_plus(stderr,

552

527

}

553

528

554

529

/* GnuTLS server initialization */

555

ret = gnutls_dh_params_init(&mc->dh_params);

530

ret = gnutls_dh_params_init(&mc.dh_params);

556

531

if(ret != GNUTLS_E_SUCCESS){

557

532

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

558

533

" initialization: %s\n",

559

534

safer_gnutls_strerror(ret));

560

535

goto globalfail;

561

536

}

562

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

537

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

563

538

if(ret != GNUTLS_E_SUCCESS){

564

539

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

565

540

safer_gnutls_strerror(ret));

566

541

goto globalfail;

567

542

}

568

543

569

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

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

570

545

571

546

return 0;

572

547

573

548

globalfail:

574

549

575

gnutls_certificate_free_credentials(mc->cred);

550

gnutls_certificate_free_credentials(mc.cred);

576

551

gnutls_global_deinit();

577

gnutls_dh_params_deinit(mc->dh_params);

552

gnutls_dh_params_deinit(mc.dh_params);

578

553

return -1;

579

554

}

580

555

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

556

static int init_gnutls_session(gnutls_session_t *session){

584

557

int ret;

585

558

/* GnuTLS session creation */

586

559

do {

598

571

{

599

572

const char *err;

600

573

do {

601

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

574

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

602

575

if(quit_now){

603

576

gnutls_deinit(*session);

604

577

return -1;

615

588

616

589

do {

617

590

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

618

mc->cred);

591

mc.cred);

619

592

if(quit_now){

620

593

gnutls_deinit(*session);

621

594

return -1;

631

604

/* ignore client certificate if any. */

632

605

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

633

606

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

635

608

636

609

return 0;

637

610

}

641

614

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

642

615

643

616

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

645

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

617

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

646

618

AvahiIfIndex if_index,

647

int af, mandos_context *mc){

619

int af){

648

620

int ret, tcp_sd = -1;

649

621

ssize_t sret;

650

struct sockaddr_storage to;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

651

626

char *buffer = NULL;

652

627

char *decrypted_buffer = NULL;

653

628

size_t buffer_length = 0;

677

652

return -1;

678

653

}

679

654

680

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

681

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

682

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

683

bool match = false;

684

{

685

char *interface = NULL;

686

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

687

interface))){

688

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

689

match = true;

690

break;

691

}

692

}

693

}

694

if(not match){

695

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

696

connect to the server */

697

if(debug){

698

char interface[IF_NAMESIZE];

699

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

700

perror_plus("if_indextoname");

701

} else {

702

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

703

" \"%s\"\n",

704

if_indextoname((unsigned int)if_index,

705

interface));

706

}

707

}

708

return -1;

709

}

710

}

711

712

ret = init_gnutls_session(&session, mc);

655

ret = init_gnutls_session(&session);

713

656

if(ret != 0){

714

657

return -1;

715

658

}

716

659

717

660

if(debug){

718

661

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

719

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

662

PRIu16 "\n", ip, port);

720

663

}

721

664

722

665

tcp_sd = socket(pf, SOCK_STREAM, 0);

734

677

735

678

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

736

679

if(af == AF_INET6){

737

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

738

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

680

to.in6.sin6_family = (sa_family_t)af;

681

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

739

682

} else { /* IPv4 */

740

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

741

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

683

to.in.sin_family = (sa_family_t)af;

684

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

742

685

}

743

686

if(ret < 0 ){

744

687

int e = errno;

753

696

goto mandos_end;

754

697

}

755

698

if(af == AF_INET6){

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

759

706

if(if_index == AVAHI_IF_UNSPEC){

760

707

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

761

708

" incomplete without a network interface\n");

763

710

goto mandos_end;

764

711

}

765

712

/* Set the network interface number as scope */

766

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

713

to.in6.sin6_scope_id = (uint32_t)if_index;

767

714

}

768

715

} else {

769

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

716

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

717

-Wconversion and

718

-Wunreachable-code */

770

719

}

771

720

772

721

if(quit_now){

780

729

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

781

730

perror_plus("if_indextoname");

782

731

} else {

783

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

784

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

732

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

733

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

785

734

}

786

735

} else {

787

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

788

ip, (uintmax_t)port);

736

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

737

ip, port);

789

738

}

790

739

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

791

740

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

741

const char *pcret;

792

742

if(af == AF_INET6){

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

743

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

744

sizeof(addrstr));

797

745

} else {

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

746

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

747

sizeof(addrstr));

802

748

}

803

if(ret == EAI_SYSTEM){

804

perror_plus("getnameinfo");

805

} else if(ret != 0) {

806

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

807

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

808

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

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

809

755

}

810

756

}

811

757

815

761

}

816

762

817

763

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

764

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

820

765

} else {

821

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

822

sizeof(struct sockaddr_in));

766

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

823

767

}

824

768

if(ret < 0){

825

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

769

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

826

770

int e = errno;

827

771

perror_plus("connect");

828

772

errno = e;

874

818

goto mandos_end;

875

819

}

876

820

877

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

878

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

879

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

880

gnutls_transport_set_ptr(session,

881

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

882

823

883

824

if(quit_now){

884

825

errno = EINTR;

989

930

if(buffer_length > 0){

990

931

ssize_t decrypted_buffer_size;

991

932

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

992

&decrypted_buffer, mc);

933

&decrypted_buffer);

993

934

if(decrypted_buffer_size >= 0){

994

935

995

936

written = 0;

1043

984

return retval;

1044

985

}

1045

986

1046

__attribute__((nonnull))

1047

987

static void resolve_callback(AvahiSServiceResolver *r,

1048

988

AvahiIfIndex interface,

1049

989

AvahiProtocol proto,

1057

997

AVAHI_GCC_UNUSED AvahiStringList *txt,

1058

998

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1059

999

flags,

1060

void *mc){

1061

if(r == NULL){

1062

return;

1063

}

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1064

1002

1065

1003

/* Called whenever a service has been resolved successfully or

1066

1004

timed out */

1075

1013

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

1076

1014

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

1077

1015

domain,

1078

avahi_strerror(avahi_server_errno

1079

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

1016

avahi_strerror(avahi_server_errno(mc.server)));

1080

1017

break;

1081

1018

1082

1019

case AVAHI_RESOLVER_FOUND:

1088

1025

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

1089

1026

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

1090

1027

}

1091

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

1092

interface,

1093

avahi_proto_to_af(proto),

1094

mc);

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1095

1030

if(ret == 0){

1096

avahi_simple_poll_quit(simple_poll);

1031

avahi_simple_poll_quit(mc.simple_poll);

1097

1032

} else {

1098

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

1099

avahi_proto_to_af(proto),

1100

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

1101

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

1102

" list\n", name);

1103

}

1033

ret = add_server(ip, port, interface,

1034

avahi_proto_to_af(proto));

1104

1035

}

1105

1036

}

1106

1037

}

1116

1047

const char *domain,

1117

1048

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1118

1049

flags,

1119

void *mc){

1120

if(b == NULL){

1121

return;

1122

}

1050

AVAHI_GCC_UNUSED void* userdata){

1051

assert(b);

1123

1052

1124

1053

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

1125

1054

is removed from the LAN */

1133

1062

case AVAHI_BROWSER_FAILURE:

1134

1063

1135

1064

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

1136

avahi_strerror(avahi_server_errno

1137

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

1138

avahi_simple_poll_quit(simple_poll);

1065

avahi_strerror(avahi_server_errno(mc.server)));

1066

avahi_simple_poll_quit(mc.simple_poll);

1139

1067

return;

1140

1068

1141

1069

case AVAHI_BROWSER_NEW:

1144

1072

the callback function is called the Avahi server will free the

1145

1073

resolver for us. */

1146

1074

1147

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

1148

interface, protocol, name, type,

1149

domain, protocol, 0,

1150

resolve_callback, mc) == NULL)

1075

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

1076

name, type, domain, protocol, 0,

1077

resolve_callback, NULL) == NULL)

1151

1078

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

1152

1079

" %s\n", name,

1153

avahi_strerror(avahi_server_errno

1154

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

1155

1081

break;

1156

1082

1157

1083

case AVAHI_BROWSER_REMOVE:

1176

1102

signal_received = sig;

1177

1103

int old_errno = errno;

1178

1104

/* set main loop to exit */

1179

if(simple_poll != NULL){

1180

avahi_simple_poll_quit(simple_poll);

1105

if(mc.simple_poll != NULL){

1106

avahi_simple_poll_quit(mc.simple_poll);

1181

1107

}

1182

1108

errno = old_errno;

1183

1109

}

1184

1110

1185

__attribute__((nonnull, warn_unused_result))

1186

1111

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

1187

1112

int ret;

1188

error_t ret_errno;

1189

1113

1190

1114

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

1191

1115

if(s < 0){

1192

ret_errno = errno;

1193

1116

perror_plus("socket");

1194

errno = ret_errno;

1195

1117

return false;

1196

1118

}

1197

1119

strcpy(ifr->ifr_name, ifname);

1198

1120

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1199

1121

if(ret == -1){

1200

1122

if(debug){

1201

ret_errno = errno;

1202

1123

perror_plus("ioctl SIOCGIFFLAGS");

1203

errno = ret_errno;

1204

1124

}

1205

1125

return false;

1206

1126

}

1207

1127

return true;

1208

1128

}

1209

1129

1210

__attribute__((nonnull, warn_unused_result))

1211

1130

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

1212

1131

1213

1132

/* Reject the loopback device */

1255

1174

* corresponds to an acceptable network device.

1256

1175

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

1257

1176

*/

1258

__attribute__((nonnull, warn_unused_result))

1259

1177

int good_interface(const struct dirent *if_entry){

1260

1178

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

1261

1179

return 0;

1277

1195

}

1278

1196

1279

1197

/*

1280

* This function determines if a network interface is up.

1281

*/

1282

__attribute__((nonnull, warn_unused_result))

1283

bool interface_is_up(const char *interface){

1284

struct ifreq ifr;

1285

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

1286

if(debug){

1287

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

1288

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

1289

}

1290

return false;

1291

}

1292

1293

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

1294

}

1295

1296

/*

1297

* This function determines if a network interface is running

1298

*/

1299

__attribute__((nonnull, warn_unused_result))

1300

bool interface_is_running(const char *interface){

1301

struct ifreq ifr;

1302

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

1303

if(debug){

1304

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

1305

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

1306

}

1307

return false;

1308

}

1309

1310

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

1311

}

1312

1313

__attribute__((nonnull, pure, warn_unused_result))

1198

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

1199

* corresponds to an acceptable network device which is up.

1200

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

1201

*/

1202

int up_interface(const struct dirent *if_entry){

1203

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

1204

return 0;

1205

}

1206

1207

struct ifreq ifr;

1208

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

1209

if(debug){

1210

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

1211

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

1212

}

1213

return 0;

1214

}

1215

1216

/* Reject down interfaces */

1217

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

1218

if(debug){

1219

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

1220

if_entry->d_name);

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject non-running interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

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

1235

return 0;

1236

}

1237

return 1;

1238

}

1239

1314

1240

int notdotentries(const struct dirent *direntry){

1315

1241

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

1316

1242

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

1323

1249

}

1324

1250

1325

1251

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

1326

__attribute__((nonnull, warn_unused_result))

1327

1252

int runnable_hook(const struct dirent *direntry){

1328

1253

int ret;

1329

1254

size_t sret;

1337

1262

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

1338

1263

"abcdefghijklmnopqrstuvwxyz"

1339

1264

"0123456789"

1340

"_.-");

1265

"_-");

1341

1266

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

1342

1267

/* Contains non-allowed characters */

1343

1268

if(debug){

1347

1272

return 0;

1348

1273

}

1349

1274

1350

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

1275

char *fullname = NULL;

1276

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

1277

if(ret < 0){

1278

perror_plus("asprintf");

1279

return 0;

1280

}

1281

1282

ret = stat(fullname, &st);

1351

1283

if(ret == -1){

1352

1284

if(debug){

1353

1285

perror_plus("Could not stat hook");

1377

1309

return 1;

1378

1310

}

1379

1311

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1312

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1383

1313

int ret;

1384

1314

struct timespec now;

1385

1315

struct timespec waited_time;

1386

1316

intmax_t block_time;

1387

1317

1388

1318

while(true){

1389

if(mc->current_server == NULL){

1390

if(debug){

1319

if(mc.current_server == NULL){

1320

if (debug){

1391

1321

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

1392

1322

" No timeout!\n");

1393

1323

}

1394

1324

ret = avahi_simple_poll_iterate(s, -1);

1395

1325

} else {

1396

if(debug){

1326

if (debug){

1397

1327

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

1398

1328

" it, or wait\n");

1399

1329

}

1406

1336

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

1407

1337

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

1408

1338

waited_time.tv_sec = (now.tv_sec

1409

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

1339

- mc.current_server->last_seen.tv_sec);

1410

1340

waited_time.tv_nsec = (now.tv_nsec

1411

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

1341

- mc.current_server->last_seen.tv_nsec);

1412

1342

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

1413

1343

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

1414

1344

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

1416

1346

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

1417

1347

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

1418

1348

1419

if(debug){

1349

if (debug){

1420

1350

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

1421

1351

block_time);

1422

1352

}

1423

1353

1424

1354

if(block_time <= 0){

1425

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

1426

mc->current_server->port,

1427

mc->current_server->if_index,

1428

mc->current_server->af, mc);

1355

ret = start_mandos_communication(mc.current_server->ip,

1356

mc.current_server->port,

1357

mc.current_server->if_index,

1358

mc.current_server->af);

1429

1359

if(ret == 0){

1430

avahi_simple_poll_quit(s);

1360

avahi_simple_poll_quit(mc.simple_poll);

1431

1361

return 0;

1432

1362

}

1433

1363

ret = clock_gettime(CLOCK_MONOTONIC,

1434

&mc->current_server->last_seen);

1364

&mc.current_server->last_seen);

1435

1365

if(ret == -1){

1436

1366

perror_plus("clock_gettime");

1437

1367

return -1;

1438

1368

}

1439

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

1369

mc.current_server = mc.current_server->next;

1440

1370

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

1441

1371

servers, but don't block */

1442

1372

}

1444

1374

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

1445

1375

}

1446

1376

if(ret != 0){

1447

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

1377

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

1448

1378

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

1449

1379

}

1450

1380

}

1451

1381

}

1452

1382

}

1453

1383

1454

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

1455

__attribute__((warn_unused_result))

1456

error_t raise_privileges(void){

1457

error_t old_errno = errno;

1458

error_t ret_errno = 0;

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

__attribute__((warn_unused_result))

1469

error_t raise_privileges_permanently(void){

1470

error_t old_errno = errno;

1471

error_t ret_errno = raise_privileges();

1472

if(ret_errno != 0){

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

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

1477

ret_errno = errno;

1478

perror_plus("seteuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

__attribute__((warn_unused_result))

1486

error_t lower_privileges(void){

1487

error_t old_errno = errno;

1488

error_t ret_errno = 0;

1489

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

1490

ret_errno = errno;

1491

perror_plus("seteuid");

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

error_t lower_privileges_permanently(void){

1500

error_t old_errno = errno;

1501

error_t ret_errno = 0;

1502

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

1503

ret_errno = errno;

1504

perror_plus("setuid");

1505

}

1506

errno = old_errno;

1507

return ret_errno;

1508

}

1509

1510

__attribute__((nonnull))

1511

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

1384

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

1512

1385

const float delay){

1513

1386

struct dirent **direntries;

1514

if(hookdir_fd == -1){

1515

hookdir_fd = open(hookdir, O_RDONLY);

1516

if(hookdir_fd == -1){

1517

if(errno == ENOENT){

1518

if(debug){

1519

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

1520

" found\n", hookdir);

1521

}

1522

} else {

1523

perror_plus("open");

1524

}

1525

return;

1526

}

1527

}

1528

#ifdef __GLIBC__

1529

#if __GLIBC_PREREQ(2, 15)

1530

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

1531

runnable_hook, alphasort);

1532

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

1533

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

1534

alphasort);

1535

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

1536

#else /* not __GLIBC__ */

1537

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

1538

alphasort);

1539

#endif /* not __GLIBC__ */

1387

struct dirent *direntry;

1388

int ret;

1389

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

1390

alphasort);

1540

1391

if(numhooks == -1){

1541

1392

perror_plus("scandir");

1542

return;

1543

}

1544

struct dirent *direntry;

1545

int ret;

1546

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

1547

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

1548

direntry = direntries[i];

1549

if(debug){

1550

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

1551

direntry->d_name);

1552

}

1553

pid_t hook_pid = fork();

1554

if(hook_pid == 0){

1555

/* Child */

1556

/* Raise privileges */

1557

if(raise_privileges_permanently() != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1590

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

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

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

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

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

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

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

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

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

1612

if(ret == -1){

1393

} else {

1394

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

1395

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

1396

direntry = direntries[i];

1397

char *fullname = NULL;

1398

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

1399

if(ret < 0){

1613

1400

perror_plus("asprintf");

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1401

continue;

1402

}

1403

if(debug){

1404

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

1405

direntry->d_name);

1406

}

1407

pid_t hook_pid = fork();

1408

if(hook_pid == 0){

1409

/* Child */

1410

/* Raise privileges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror_plus("seteuid");

1415

}

1416

/* Raise privileges even more */

1417

errno = 0;

1418

ret = setuid(0);

1419

if(ret == -1){

1420

perror_plus("setuid");

1421

}

1422

/* Set group */

1423

errno = 0;

1424

ret = setgid(0);

1425

if(ret == -1){

1426

perror_plus("setgid");

1427

}

1428

/* Reset supplementary groups */

1429

errno = 0;

1430

ret = setgroups(0, NULL);

1431

if(ret == -1){

1432

perror_plus("setgroups");

1433

}

1434

dup2(devnull, STDIN_FILENO);

1435

close(devnull);

1436

dup2(STDERR_FILENO, STDOUT_FILENO);

1437

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

1438

if(ret == -1){

1439

perror_plus("setenv");

1440

_exit(EX_OSERR);

1441

}

1442

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

1443

if(ret == -1){

1444

perror_plus("setenv");

1445

_exit(EX_OSERR);

1446

}

1447

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

1448

if(ret == -1){

1449

perror_plus("setenv");

1450

_exit(EX_OSERR);

1451

}

1452

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

1453

if(ret == -1){

1454

perror_plus("setenv");

1455

_exit(EX_OSERR);

1456

}

1457

char *delaystring;

1458

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

1459

if(ret == -1){

1460

perror_plus("asprintf");

1461

_exit(EX_OSERR);

1462

}

1463

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

1464

if(ret == -1){

1465

free(delaystring);

1466

perror_plus("setenv");

1467

_exit(EX_OSERR);

1468

}

1618

1469

free(delaystring);

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

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

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

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

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

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

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

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

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

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

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

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

1653

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

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

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

1659

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

1660

WTERMSIG(status));

1661

continue;

1662

} else {

1663

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

1664

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

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

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

1670

direntry->d_name);

1671

}

1672

}

1673

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

1674

perror_plus("close");

1675

} else {

1676

hookdir_fd = -1;

1677

}

1678

close(devnull);

1679

}

1680

1681

__attribute__((nonnull, warn_unused_result))

1682

error_t bring_up_interface(const char *const interface,

1683

const float delay){

1684

error_t old_errno = errno;

1685

int ret;

1686

struct ifreq network;

1687

unsigned int if_index = if_nametoindex(interface);

1688

if(if_index == 0){

1689

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

1690

errno = old_errno;

1691

return ENXIO;

1692

}

1693

1694

if(quit_now){

1695

errno = old_errno;

1696

return EINTR;

1697

}

1698

1699

if(not interface_is_up(interface)){

1700

error_t ret_errno = 0, ioctl_errno = 0;

1701

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

1702

ret_errno = errno;

1703

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

1704

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

1705

errno = old_errno;

1706

return ret_errno;

1707

}

1708

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

1709

1710

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

1711

if(sd == -1){

1712

ret_errno = errno;

1713

perror_plus("socket");

1714

errno = old_errno;

1715

return ret_errno;

1716

}

1717

1718

if(quit_now){

1719

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

1720

if(ret == -1){

1721

perror_plus("close");

1722

}

1723

errno = old_errno;

1724

return EINTR;

1725

}

1726

1727

if(debug){

1728

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

1729

interface);

1730

}

1731

1732

/* Raise privileges */

1733

ret_errno = raise_privileges();

1734

if(ret_errno != 0){

1735

perror_plus("Failed to raise privileges");

1736

}

1737

1738

#ifdef __linux__

1739

int ret_linux;

1740

bool restore_loglevel = false;

1741

if(ret_errno == 0){

1742

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1743

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

1744

ret_linux = klogctl(8, NULL, 5);

1745

if(ret_linux == -1){

1746

perror_plus("klogctl");

1747

} else {

1748

restore_loglevel = true;

1749

}

1750

}

1751

#endif /* __linux__ */

1752

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

1753

ioctl_errno = errno;

1754

#ifdef __linux__

1755

if(restore_loglevel){

1756

ret_linux = klogctl(7, NULL, 0);

1757

if(ret_linux == -1){

1758

perror_plus("klogctl");

1759

}

1760

}

1761

#endif /* __linux__ */

1762

1763

/* If raise_privileges() succeeded above */

1764

if(ret_errno == 0){

1765

/* Lower privileges */

1766

ret_errno = lower_privileges();

1767

if(ret_errno != 0){

1768

errno = ret_errno;

1769

perror_plus("Failed to lower privileges");

1770

}

1771

}

1772

1773

/* Close the socket */

1774

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

1775

if(ret == -1){

1776

perror_plus("close");

1777

}

1778

1779

if(ret_setflags == -1){

1780

errno = ioctl_errno;

1781

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1782

errno = old_errno;

1783

return ioctl_errno;

1784

}

1785

} else if(debug){

1786

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

1787

interface);

1788

}

1789

1790

/* Sleep checking until interface is running.

1791

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

1792

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

1793

if(interface_is_running(interface)){

1794

break;

1795

}

1796

struct timespec sleeptime = { .tv_nsec = 250000000 };

1797

ret = nanosleep(&sleeptime, NULL);

1798

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

1799

perror_plus("nanosleep");

1800

}

1801

}

1802

1803

errno = old_errno;

1804

return 0;

1805

}

1806

1807

__attribute__((nonnull, warn_unused_result))

1808

error_t take_down_interface(const char *const interface){

1809

error_t old_errno = errno;

1810

struct ifreq network;

1811

unsigned int if_index = if_nametoindex(interface);

1812

if(if_index == 0){

1813

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

1814

errno = old_errno;

1815

return ENXIO;

1816

}

1817

if(interface_is_up(interface)){

1818

error_t ret_errno = 0, ioctl_errno = 0;

1819

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

1820

ret_errno = errno;

1821

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

1822

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

1823

errno = old_errno;

1824

return ret_errno;

1825

}

1826

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

1827

1828

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

1829

if(sd == -1){

1830

ret_errno = errno;

1831

perror_plus("socket");

1832

errno = old_errno;

1833

return ret_errno;

1834

}

1835

1836

if(debug){

1837

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

1838

interface);

1839

}

1840

1841

/* Raise privileges */

1842

ret_errno = raise_privileges();

1843

if(ret_errno != 0){

1844

perror_plus("Failed to raise privileges");

1845

}

1846

1847

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

1848

ioctl_errno = errno;

1849

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

1859

1860

/* Close the socket */

1861

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

1862

if(ret == -1){

1863

perror_plus("close");

1864

}

1865

1866

if(ret_setflags == -1){

1867

errno = ioctl_errno;

1868

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1869

errno = old_errno;

1870

return ioctl_errno;

1871

}

1872

} else if(debug){

1873

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

1874

interface);

1875

}

1876

1877

errno = old_errno;

1878

return 0;

1470

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

1471

perror_plus("execl");

1472

} else {

1473

int status;

1474

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

1475

perror_plus("waitpid");

1476

free(fullname);

1477

continue;

1478

}

1479

if(WIFEXITED(status)){

1480

if(WEXITSTATUS(status) != 0){

1481

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

1482

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

1483

WEXITSTATUS(status));

1484

free(fullname);

1485

continue;

1486

}

1487

} else if(WIFSIGNALED(status)){

1488

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

1489

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

1490

WTERMSIG(status));

1491

free(fullname);

1492

continue;

1493

} else {

1494

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

1495

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

1496

free(fullname);

1497

continue;

1498

}

1499

}

1500

free(fullname);

1501

if(debug){

1502

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

1503

direntry->d_name);

1504

}

1505

}

1506

close(devnull);

1507

}

1508

return true;

1879

1509

}

1880

1510

1881

1511

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

1882

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

1883

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

1884

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

1885

.interfaces = NULL, .interfaces_size = 0 };

1886

1512

AvahiSServiceBrowser *sb = NULL;

1887

error_t ret_errno;

1513

int error;

1888

1514

int ret;

1889

1515

intmax_t tmpmax;

1890

1516

char *tmp;

1891

1517

int exitcode = EXIT_SUCCESS;

1892

char *interfaces_to_take_down = NULL;

1893

size_t interfaces_to_take_down_size = 0;

1894

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

1895

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

1896

char *tempdir = NULL;

1518

const char *interface = "";

1519

struct ifreq network;

1520

int sd = -1;

1521

bool take_down_interface = false;

1522

uid_t uid;

1523

gid_t gid;

1524

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

1525

bool tempdir_created = false;

1897

1526

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1898

1527

const char *seckey = PATHDIR "/" SECKEY;

1899

1528

const char *pubkey = PATHDIR "/" PUBKEY;

1900

char *interfaces_hooks = NULL;

1901

1529

1902

1530

bool gnutls_initialized = false;

1903

1531

bool gpgme_initialized = false;

1965

1593

.group = 2 },

1966

1594

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

1967

1595

.arg = "SECONDS",

1968

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

1596

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

1969

1597

.group = 2 },

1970

1598

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

1971

1599

.arg = "DIR",

1994

1622

connect_to = arg;

1995

1623

break;

1996

1624

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

1997

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

1998

arg, (int)',');

1999

if(ret_errno != 0){

2000

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

2001

}

1625

interface = arg;

2002

1626

break;

2003

1627

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

2004

1628

seckey = arg;

2047

1671

argp_state_help(state, state->out_stream,

2048

1672

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2049

1673

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

1674

fprintf_plus(state->out_stream,

1675

"Mandos plugin mandos-client: ");

2050

1676

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

2051

1677

exit(argp_err_exit_status);

2052

1678

break;

2081

1707

/* Work around Debian bug #633582:

2082

1708

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

2083

1709

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

1710

/* Re-raise priviliges */

1711

errno = 0;

1712

ret = seteuid(0);

1713

if(ret == -1){

1714

perror_plus("seteuid");

2089

1715

} else {

2090

1716

struct stat st;

2091

1717

2132

1758

}

2133

1759

2134

1760

/* Lower privileges */

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

2139

}

2140

}

2141

}

2142

2143

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

2144

{

2145

char *interface = NULL;

2146

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

2147

interface))){

2148

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

2149

and if_nametoindex(interface) == 0){

2150

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

2151

fprintf_plus(stderr, "Not using nonexisting interface"

2152

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

2153

}

2154

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

2155

interface = NULL;

1761

errno = 0;

1762

ret = seteuid(uid);

1763

if(ret == -1){

1764

perror_plus("seteuid");

2156

1765

}

2157

1766

}

2158

1767

}

2159

1768

2160

1769

/* Run network hooks */

2161

{

2162

if(mc.interfaces != NULL){

2163

interfaces_hooks = malloc(mc.interfaces_size);

2164

if(interfaces_hooks == NULL){

2165

perror_plus("malloc");

2166

goto end;

2167

}

2168

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

2169

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

2170

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

1770

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

1771

goto end;

2173

1772

}

2174

1773

2175

1774

if(not debug){

2176

1775

avahi_set_log_function(empty_log);

2177

1776

}

2178

1777

1778

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

1779

struct dirent **direntries;

1780

/* First look for interfaces that are up */

1781

ret = scandir(sys_class_net, &direntries, up_interface,

1782

alphasort);

1783

if(ret == 0){

1784

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

1785

free(direntries);

1786

ret = scandir(sys_class_net, &direntries, good_interface,

1787

alphasort);

1788

}

1789

if(ret >= 1){

1790

/* Pick the first interface returned */

1791

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

1792

if(debug){

1793

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

1794

}

1795

if(interface == NULL){

1796

perror_plus("malloc");

1797

free(direntries);

1798

exitcode = EXIT_FAILURE;

1799

goto end;

1800

}

1801

free(direntries);

1802

} else {

1803

free(direntries);

1804

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

1805

exitcode = EXIT_FAILURE;

1806

goto end;

1807

}

1808

}

1809

2179

1810

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

2180

1811

from the signal handler */

2181

1812

/* Initialize the pseudo-RNG for Avahi */

2182

1813

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

2183

simple_poll = avahi_simple_poll_new();

2184

if(simple_poll == NULL){

1814

mc.simple_poll = avahi_simple_poll_new();

1815

if(mc.simple_poll == NULL){

2185

1816

fprintf_plus(stderr,

2186

1817

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

2187

1818

exitcode = EX_UNAVAILABLE;

2251

1882

}

2252

1883

}

2253

1884

2254

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

2255

if(mc.interfaces == NULL){

2256

struct dirent **direntries = NULL;

2257

/* Look for any good interfaces */

2258

ret = scandir(sys_class_net, &direntries, good_interface,

2259

alphasort);

2260

if(ret >= 1){

2261

/* Add all found interfaces to interfaces list */

2262

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

2263

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

2264

direntries[i]->d_name);

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2267

perror_plus("argz_add");

2268

continue;

2269

}

2270

if(debug){

2271

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

2272

direntries[i]->d_name);

2273

}

2274

}

2275

free(direntries);

2276

} else {

2277

free(direntries);

2278

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

2279

exitcode = EXIT_FAILURE;

2280

goto end;

2281

}

2282

}

2283

2284

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

2285

{

2286

char *interface = NULL;

2287

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

2288

interface))){

2289

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

2290

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

2291

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

2292

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

2293

interface);

2294

interface = NULL;

2295

while((interface = argz_next(mc.interfaces,

2296

mc.interfaces_size, interface))){

2297

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

2298

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

2299

interface);

2300

interface = NULL;

1885

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

1886

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

1887

if_index = (AvahiIfIndex) if_nametoindex(interface);

1888

if(if_index == 0){

1889

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

1890

exitcode = EX_UNAVAILABLE;

1891

goto end;

1892

}

1893

1894

if(quit_now){

1895

goto end;

1896

}

1897

1898

/* Re-raise priviliges */

1899

errno = 0;

1900

ret = seteuid(0);

1901

if(ret == -1){

1902

perror_plus("seteuid");

1903

}

1904

1905

#ifdef __linux__

1906

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1907

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

1908

ret = klogctl(8, NULL, 5);

1909

bool restore_loglevel = true;

1910

if(ret == -1){

1911

restore_loglevel = false;

1912

perror_plus("klogctl");

1913

}

1914

#endif /* __linux__ */

1915

1916

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1917

if(sd < 0){

1918

perror_plus("socket");

1919

exitcode = EX_OSERR;

1920

#ifdef __linux__

1921

if(restore_loglevel){

1922

ret = klogctl(7, NULL, 0);

1923

if(ret == -1){

1924

perror_plus("klogctl");

1925

}

1926

}

1927

#endif /* __linux__ */

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

strcpy(network.ifr_name, interface);

1937

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

1938

if(ret == -1){

1939

perror_plus("ioctl SIOCGIFFLAGS");

1940

#ifdef __linux__

1941

if(restore_loglevel){

1942

ret = klogctl(7, NULL, 0);

1943

if(ret == -1){

1944

perror_plus("klogctl");

1945

}

1946

}

1947

#endif /* __linux__ */

1948

exitcode = EX_OSERR;

1949

/* Lower privileges */

1950

errno = 0;

1951

ret = seteuid(uid);

1952

if(ret == -1){

1953

perror_plus("seteuid");

1954

}

1955

goto end;

1956

}

1957

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

1958

network.ifr_flags |= IFF_UP;

1959

take_down_interface = true;

1960

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

1961

if(ret == -1){

1962

take_down_interface = false;

1963

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1964

exitcode = EX_OSERR;

1965

#ifdef __linux__

1966

if(restore_loglevel){

1967

ret = klogctl(7, NULL, 0);

1968

if(ret == -1){

1969

perror_plus("klogctl");

2301

1970

}

2302

1971

}

1972

#endif /* __linux__ */

1973

/* Lower privileges */

1974

errno = 0;

1975

ret = seteuid(uid);

1976

if(ret == -1){

1977

perror_plus("seteuid");

1978

}

1979

goto end;

1980

}

1981

}

1982

/* Sleep checking until interface is running.

1983

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

1984

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

1985

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

1986

if(ret == -1){

1987

perror_plus("ioctl SIOCGIFFLAGS");

1988

} else if(network.ifr_flags & IFF_RUNNING){

2303

1989

break;

2304

1990

}

2305

bool interface_was_up = interface_is_up(interface);

2306

errno = bring_up_interface(interface, delay);

2307

if(not interface_was_up){

2308

if(errno != 0){

2309

perror_plus("Failed to bring up interface");

2310

} else {

2311

errno = argz_add(&interfaces_to_take_down,

2312

&interfaces_to_take_down_size,

2313

interface);

2314

if(errno != 0){

2315

perror_plus("argz_add");

2316

}

2317

}

2318

}

2319

}

2320

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

2321

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

2322

}

2323

}

2324

2325

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

2326

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

2327

if(debug){

2328

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

2329

mc.interfaces);

2330

}

2331

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

1991

struct timespec sleeptime = { .tv_nsec = 250000000 };

1992

ret = nanosleep(&sleeptime, NULL);

1993

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

1994

perror_plus("nanosleep");

1995

}

1996

}

1997

if(not take_down_interface){

1998

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

1999

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

2000

if(ret == -1){

2001

perror_plus("close");

2002

}

2003

}

2004

#ifdef __linux__

2005

if(restore_loglevel){

2006

/* Restores kernel loglevel to default */

2007

ret = klogctl(7, NULL, 0);

2008

if(ret == -1){

2009

perror_plus("klogctl");

2010

}

2011

}

2012

#endif /* __linux__ */

2013

/* Lower privileges */

2014

errno = 0;

2015

/* Lower privileges */

2016

ret = seteuid(uid);

2017

if(ret == -1){

2018

perror_plus("seteuid");

2019

}

2332

2020

}

2333

2021

2334

2022

if(quit_now){

2335

2023

goto end;

2336

2024

}

2337

2025

2338

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

2026

ret = init_gnutls_global(pubkey, seckey);

2339

2027

if(ret == -1){

2340

2028

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

2341

2029

exitcode = EX_UNAVAILABLE;

2348

2036

goto end;

2349

2037

}

2350

2038

2351

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

2352

tempdir = mkdtemp(run_tempdir);

2353

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

2354

if(debug){

2355

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

2356

run_tempdir, old_tempdir);

2357

}

2358

tempdir = mkdtemp(old_tempdir);

2359

}

2360

if(tempdir == NULL){

2039

if(mkdtemp(tempdir) == NULL){

2361

2040

perror_plus("mkdtemp");

2362

2041

goto end;

2363

2042

}

2043

tempdir_created = true;

2364

2044

2365

2045

if(quit_now){

2366

2046

goto end;

2367

2047

}

2368

2048

2369

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

2049

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

2370

2050

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

2371

2051

exitcode = EX_UNAVAILABLE;

2372

2052

goto end;

2382

2062

/* Connect directly, do not use Zeroconf */

2383

2063

/* (Mainly meant for debugging) */

2384

2064

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

2385

2386

2065

if(address == NULL){

2387

2066

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

2388

2067

exitcode = EX_USAGE;

2393

2072

goto end;

2394

2073

}

2395

2074

2396

in_port_t port;

2075

uint16_t port;

2397

2076

errno = 0;

2398

2077

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

2399

2078

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

2400

or tmpmax != (in_port_t)tmpmax){

2079

or tmpmax != (uint16_t)tmpmax){

2401

2080

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

2402

2081

exitcode = EX_USAGE;

2403

2082

goto end;

2404

2083

}

2405

2084

2406

2085

if(quit_now){

2407

2086

goto end;

2408

2087

}

2409

2088

2410

port = (in_port_t)tmpmax;

2089

port = (uint16_t)tmpmax;

2411

2090

*address = '\0';

2412

2091

/* Colon in address indicates IPv6 */

2413

2092

int af;

2429

2108

}

2430

2109

2431

2110

while(not quit_now){

2432

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

2433

&mc);

2111

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

2434

2112

if(quit_now or ret == 0){

2435

2113

break;

2436

2114

}

2438

2116

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

2439

2117

(int)retry_interval);

2440

2118

}

2441

sleep((unsigned int)retry_interval);

2119

sleep((int)retry_interval);

2442

2120

}

2443

2121

2444

if(not quit_now){

2122

if (not quit_now){

2445

2123

exitcode = EXIT_SUCCESS;

2446

2124

}

2447

2125

2462

2140

config.publish_domain = 0;

2463

2141

2464

2142

/* Allocate a new server */

2465

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2466

&config, NULL, NULL, &ret_errno);

2143

mc.server = avahi_server_new(avahi_simple_poll_get

2144

(mc.simple_poll), &config, NULL,

2145

NULL, &error);

2467

2146

2468

2147

/* Free the Avahi configuration data */

2469

2148

avahi_server_config_free(&config);

2472

2151

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

2473

2152

if(mc.server == NULL){

2474

2153

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

2475

avahi_strerror(ret_errno));

2154

avahi_strerror(error));

2476

2155

exitcode = EX_UNAVAILABLE;

2477

2156

goto end;

2478

2157

}

2484

2163

/* Create the Avahi service browser */

2485

2164

sb = avahi_s_service_browser_new(mc.server, if_index,

2486

2165

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2487

NULL, 0, browse_callback,

2488

(void *)&mc);

2166

NULL, 0, browse_callback, NULL);

2489

2167

if(sb == NULL){

2490

2168

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

2491

2169

avahi_strerror(avahi_server_errno(mc.server)));

2502

2180

if(debug){

2503

2181

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

2504

2182

}

2505

2506

ret = avahi_loop_with_timeout(simple_poll,

2507

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

2183

2184

ret = avahi_loop_with_timeout(mc.simple_poll,

2185

(int)(retry_interval * 1000));

2508

2186

if(debug){

2509

2187

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

2510

2188

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

2517

2195

}

2518

2196

2519

2197

/* Cleanup things */

2520

free(mc.interfaces);

2521

2522

2198

if(sb != NULL)

2523

2199

avahi_s_service_browser_free(sb);

2524

2200

2525

2201

if(mc.server != NULL)

2526

2202

avahi_server_free(mc.server);

2527

2203

2528

if(simple_poll != NULL)

2529

avahi_simple_poll_free(simple_poll);

2204

if(mc.simple_poll != NULL)

2205

avahi_simple_poll_free(mc.simple_poll);

2530

2206

2531

2207

if(gnutls_initialized){

2532

2208

gnutls_certificate_free_credentials(mc.cred);

2549

2225

}

2550

2226

}

2551

2227

2552

/* Re-raise privileges */

2228

/* Run network hooks */

2229

run_network_hooks("stop", interface, delay);

2230

2231

/* Re-raise priviliges */

2553

2232

{

2554

ret_errno = raise_privileges();

2555

if(ret_errno != 0){

2556

perror_plus("Failed to raise privileges");

2557

} else {

2558

2559

/* Run network hooks */

2560

run_network_hooks("stop", interfaces_hooks != NULL ?

2561

interfaces_hooks : "", delay);

2562

2563

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

2564

{

2565

char *interface = NULL;

2566

while((interface=argz_next(interfaces_to_take_down,

2567

interfaces_to_take_down_size,

2568

interface))){

2569

ret_errno = take_down_interface(interface);

2570

if(ret_errno != 0){

2571

errno = ret_errno;

2572

perror_plus("Failed to take down interface");

2573

}

2574

}

2575

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

2576

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

2577

" down\n");

2578

}

2579

}

2233

errno = 0;

2234

ret = seteuid(0);

2235

if(ret == -1){

2236

perror_plus("seteuid");

2580

2237

}

2581

2238

2582

ret_errno = lower_privileges_permanently();

2583

if(ret_errno != 0){

2584

perror_plus("Failed to lower privileges permanently");

2239

/* Take down the network interface */

2240

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

2241

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

2242

if(ret == -1){

2243

perror_plus("ioctl SIOCGIFFLAGS");

2244

} else if(network.ifr_flags & IFF_UP){

2245

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

2246

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

2247

if(ret == -1){

2248

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2249

}

2250

}

2251

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

2252

if(ret == -1){

2253

perror_plus("close");

2254

}

2585

2255

}

2586

2256

}

2587

2588

free(interfaces_to_take_down);

2589

free(interfaces_hooks);

2257

/* Lower privileges permanently */

2258

errno = 0;

2259

ret = setuid(uid);

2260

if(ret == -1){

2261

perror_plus("setuid");

2262

}

2590

2263

2591

2264

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

2592

if(tempdir != NULL){

2265

if(tempdir_created){

2593

2266

struct dirent **direntries = NULL;

2594

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

2595

O_NOFOLLOW));

2596

if(tempdir_fd == -1){

2597

perror_plus("open");

2598

} else {

2599

#ifdef __GLIBC__

2600

#if __GLIBC_PREREQ(2, 15)

2601

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

2602

notdotentries, alphasort);

2603

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

2604

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

2605

alphasort);

2606

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

2607

#else /* not __GLIBC__ */

2608

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

2609

alphasort);

2610

#endif /* not __GLIBC__ */

2611

if(numentries > 0){

2612

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

2613

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

2614

if(ret == -1){

2615

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

2616

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

2617

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

2618

}

2619

}

2620

2621

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

2622

free(direntries);

2623

if(numentries == -1){

2624

perror_plus("scandir");

2625

}

2626

ret = rmdir(tempdir);

2627

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

2628

perror_plus("rmdir");

2629

}

2267

struct dirent *direntry = NULL;

2268

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

2269

alphasort);

2270

if (numentries > 0){

2271

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

2272

direntry = direntries[i];

2273

char *fullname = NULL;

2274

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

2275

direntry->d_name);

2276

if(ret < 0){

2277

perror_plus("asprintf");

2278

continue;

2279

}

2280

ret = remove(fullname);

2281

if(ret == -1){

2282

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

2283

strerror(errno));

2284

}

2285

free(fullname);

2630

2286

}

2631

TEMP_FAILURE_RETRY(close(tempdir_fd));

2287

}

2288

2289

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

2290

free(direntries);

2291

if (numentries == -1){

2292

perror_plus("scandir");

2293

}

2294

ret = rmdir(tempdir);

2295

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

2296

perror_plus("rmdir");

2632

2297

}

2633

2298

}

2634

2299