/mandos/trunk : revision 738.1.1

9

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

10

*

11

* Everything else is

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13

12

13

14

*

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* 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

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

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#endif /* not _FILE_OFFSET_BITS */

39

40

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

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42

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

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stdout, ferror(), remove() */

44

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

43

stdout, ferror() */

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(),

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

58

inet_pton(), connect(),

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getnameinfo() */

60

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

60

61

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

61

62

*/

62

63

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

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64

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() */

77

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

76

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

77

unlinkat() */

78

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

78

79

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

79

80

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

80

81

argp_state, struct argp,

87

88

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

89

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

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90

WEXITSTATUS(), WTERMSIG() */

91

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

92

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

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argz_delete(), argz_append(),

94

argz_stringify(), argz_add(),

95

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

90

98

91

99

#ifdef __linux__

92

100

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

134

142

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

135

143

char *connect_to = NULL;

136

144

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

147

gid_t gid = 65534;

137

148

138

149

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

139

150

typedef struct server{

140

151

const char *ip;

141

uint16_t port;

152

in_port_t port;

142

153

AvahiIfIndex if_index;

143

154

int af;

144

155

struct timespec last_seen;

148

159

149

160

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

150

161

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

162

AvahiServer *server;

153

163

gnutls_certificate_credentials_t cred;

154

164

unsigned int dh_bits;

156

166

const char *priority;

157

167

gpgme_ctx_t ctx;

158

168

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

159

171

} mandos_context;

160

172

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

166

175

167

176

sig_atomic_t quit_now = 0;

168

177

int signal_received = 0;

169

178

170

179

/* Function to use when printing errors */

171

180

void perror_plus(const char *print_text){

181

int e = errno;

172

182

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

173

183

program_invocation_short_name);

184

errno = e;

174

185

perror(print_text);

175

186

}

176

187

188

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

177

189

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

178

190

va_list ap;

179

191

va_start (ap, format);

180

192

181

193

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

182

194

program_invocation_short_name));

183

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

195

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

184

196

}

185

197

186

198

/*

188

200

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

189

201

* "buffer_length" is how much is already used.

190

202

*/

203

__attribute__((nonnull, warn_unused_result))

191

204

size_t incbuffer(char **buffer, size_t buffer_length,

192

205

size_t buffer_capacity){

193

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

194

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

195

if(buffer == NULL){

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;

196

213

return 0;

197

214

}

215

*buffer = new_buf;

198

216

buffer_capacity += BUFFER_SIZE;

199

217

}

200

218

return buffer_capacity;

201

219

}

202

220

203

221

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

204

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

205

int af){

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){

206

225

int ret;

207

226

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

208

227

if(new_server == NULL){

209

228

perror_plus("malloc");

210

return -1;

229

return false;

211

230

}

212

231

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

213

232

.port = port,

215

234

.af = af };

216

235

if(new_server->ip == NULL){

217

236

perror_plus("strdup");

218

return -1;

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

219

253

}

220

254

/* Special case of first server */

221

if (mc.current_server == NULL){

255

if(*current_server == NULL){

222

256

new_server->next = new_server;

223

257

new_server->prev = new_server;

224

mc.current_server = new_server;

225

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

258

*current_server = new_server;

226

259

} else {

227

new_server->next = mc.current_server;

228

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

260

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

261

new_server->next = *current_server;

262

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

229

263

new_server->prev->next = new_server;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

264

(*current_server)->prev = new_server;

265

}

266

return true;

238

267

}

239

268

240

269

/*

241

270

* Initialize GPGME.

242

271

*/

243

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

244

const char *tempdir){

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){

245

277

gpgme_error_t rc;

246

278

gpgme_engine_info_t engine_info;

247

279

248

249

280

/*

250

281

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

251

282

*/

252

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

253

284

int ret;

254

285

int fd;

255

286

gpgme_data_t pgp_data;

267

298

return false;

268

299

}

269

300

270

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

271

302

if(rc != GPG_ERR_NO_ERROR){

272

303

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

273

304

gpgme_strsource(rc), gpgme_strerror(rc));

317

348

}

318

349

319

350

/* Create new GPGME "context" */

320

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

351

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

321

352

if(rc != GPG_ERR_NO_ERROR){

322

353

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

323

354

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

336

367

* Decrypt OpenPGP data.

337

368

* Returns -1 on error

338

369

*/

370

__attribute__((nonnull, warn_unused_result))

339

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

372

size_t crypto_size,

341

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

342

375

gpgme_data_t dh_crypto, dh_plain;

343

376

gpgme_error_t rc;

344

377

ssize_t ret;

370

403

371

404

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

372

405

data buffer */

373

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

406

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

374

407

if(rc != GPG_ERR_NO_ERROR){

375

408

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

376

409

gpgme_strsource(rc), gpgme_strerror(rc));

377

410

plaintext_length = -1;

378

411

if(debug){

379

412

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

381

414

if(result == NULL){

382

415

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

383

416

} else {

460

493

return plaintext_length;

461

494

}

462

495

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

466

499

if(ret == NULL)

467

500

ret = "(unknown)";

468

501

return ret;

469

502

}

470

503

471

504

/* GnuTLS log function callback */

505

__attribute__((nonnull))

472

506

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

473

507

const char* string){

474

508

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

475

509

}

476

510

511

__attribute__((nonnull, warn_unused_result))

477

512

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

513

const char *seckeyfilename,

514

mandos_context *mc){

479

515

int ret;

480

516

481

517

if(debug){

498

534

}

499

535

500

536

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

538

if(ret != GNUTLS_E_SUCCESS){

503

539

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

504

540

safer_gnutls_strerror(ret));

514

550

}

515

551

516

552

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

553

(mc->cred, pubkeyfilename, seckeyfilename,

518

554

GNUTLS_OPENPGP_FMT_BASE64);

519

555

if(ret != GNUTLS_E_SUCCESS){

520

556

fprintf_plus(stderr,

526

562

}

527

563

528

564

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

565

ret = gnutls_dh_params_init(&mc->dh_params);

530

566

if(ret != GNUTLS_E_SUCCESS){

531

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

568

" initialization: %s\n",

533

569

safer_gnutls_strerror(ret));

534

570

goto globalfail;

535

571

}

536

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

572

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

537

573

if(ret != GNUTLS_E_SUCCESS){

538

574

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

539

575

safer_gnutls_strerror(ret));

540

576

goto globalfail;

541

577

}

542

578

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

579

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

544

580

545

581

return 0;

546

582

547

583

globalfail:

548

584

549

gnutls_certificate_free_credentials(mc.cred);

585

gnutls_certificate_free_credentials(mc->cred);

550

586

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

587

gnutls_dh_params_deinit(mc->dh_params);

552

588

return -1;

553

589

}

554

590

555

static int init_gnutls_session(gnutls_session_t *session){

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

556

594

int ret;

557

595

/* GnuTLS session creation */

558

596

do {

570

608

{

571

609

const char *err;

572

610

do {

573

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

611

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

574

612

if(quit_now){

575

613

gnutls_deinit(*session);

576

614

return -1;

587

625

588

626

do {

589

627

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

628

mc->cred);

591

629

if(quit_now){

592

630

gnutls_deinit(*session);

593

631

return -1;

603

641

/* ignore client certificate if any. */

604

642

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

643

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

607

645

608

646

return 0;

609

647

}

613

651

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

614

652

615

653

/* Called when a Mandos server is found */

616

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

654

__attribute__((nonnull, warn_unused_result))

655

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

617

656

AvahiIfIndex if_index,

618

int af){

657

int af, mandos_context *mc){

619

658

int ret, tcp_sd = -1;

620

659

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

660

struct sockaddr_storage to;

625

661

char *buffer = NULL;

626

662

char *decrypted_buffer = NULL;

627

663

size_t buffer_length = 0;

651

687

return -1;

652

688

}

653

689

654

ret = init_gnutls_session(&session);

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);

655

723

if(ret != 0){

656

724

return -1;

657

725

}

658

726

659

727

if(debug){

660

728

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

661

PRIu16 "\n", ip, port);

729

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

662

730

}

663

731

664

732

tcp_sd = socket(pf, SOCK_STREAM, 0);

676

744

677

745

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

678

746

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

747

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

748

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

681

749

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

750

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

751

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

684

752

}

685

753

if(ret < 0 ){

686

754

int e = errno;

695

763

goto mandos_end;

696

764

}

697

765

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

766

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

767

if(IN6_IS_ADDR_LINKLOCAL

768

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

705

769

if(if_index == AVAHI_IF_UNSPEC){

706

770

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

707

771

" incomplete without a network interface\n");

709

773

goto mandos_end;

710

774

}

711

775

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

776

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

713

777

}

714

778

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

779

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

718

780

}

719

781

720

782

if(quit_now){

728

790

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

729

791

perror_plus("if_indextoname");

730

792

} else {

731

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

732

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

793

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

794

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

733

795

}

734

796

} else {

735

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

736

ip, port);

797

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

798

ip, (uintmax_t)port);

737

799

}

738

800

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

801

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

741

802

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

744

807

} else {

745

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

746

sizeof(addrstr));

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

747

812

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

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);

754

819

}

755

820

}

756

821

760

825

}

761

826

762

827

if(af == AF_INET6){

763

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

828

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

829

sizeof(struct sockaddr_in6));

764

830

} else {

765

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

831

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

832

sizeof(struct sockaddr_in));

766

833

}

767

834

if(ret < 0){

768

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

835

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

769

836

int e = errno;

770

837

perror_plus("connect");

771

838

errno = e;

817

884

goto mandos_end;

818

885

}

819

886

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

887

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

888

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

889

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

890

gnutls_transport_set_ptr(session,

891

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

892

823

893

if(quit_now){

824

894

errno = EINTR;

929

999

if(buffer_length > 0){

930

1000

ssize_t decrypted_buffer_size;

931

1001

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1002

&decrypted_buffer, mc);

933

1003

if(decrypted_buffer_size >= 0){

934

1004

935

1005

written = 0;

983

1053

return retval;

984

1054

}

985

1055

1056

__attribute__((nonnull))

986

1057

static void resolve_callback(AvahiSServiceResolver *r,

987

1058

AvahiIfIndex interface,

988

1059

AvahiProtocol proto,

996

1067

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1068

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1069

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1070

void *mc){

1071

if(r == NULL){

1072

return;

1073

}

1001

1074

1002

1075

/* Called whenever a service has been resolved successfully or

1003

1076

timed out */

1004

1077

1005

1078

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1006

1080

return;

1007

1081

}

1008

1082

1012

1086

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

1013

1087

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

1014

1088

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1089

avahi_strerror(avahi_server_errno

1090

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

1016

1091

break;

1017

1092

1018

1093

case AVAHI_RESOLVER_FOUND:

1024

1099

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

1025

1100

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

1026

1101

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1102

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

1103

interface,

1104

avahi_proto_to_af(proto),

1105

mc);

1029

1106

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1107

avahi_simple_poll_quit(simple_poll);

1031

1108

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1109

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

1110

avahi_proto_to_af(proto),

1111

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

1112

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

1113

" list\n", name);

1114

}

1034

1115

}

1035

1116

}

1036

1117

}

1046

1127

const char *domain,

1047

1128

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1129

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1130

void *mc){

1131

if(b == NULL){

1132

return;

1133

}

1051

1134

1052

1135

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

1053

1136

is removed from the LAN */

1061

1144

case AVAHI_BROWSER_FAILURE:

1062

1145

1063

1146

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1147

avahi_strerror(avahi_server_errno

1148

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

1149

avahi_simple_poll_quit(simple_poll);

1066

1150

return;

1067

1151

1068

1152

case AVAHI_BROWSER_NEW:

1071

1155

the callback function is called the Avahi server will free the

1072

1156

resolver for us. */

1073

1157

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

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)

1077

1162

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

1078

1163

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1164

avahi_strerror(avahi_server_errno

1165

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

1080

1166

break;

1081

1167

1082

1168

case AVAHI_BROWSER_REMOVE:

1101

1187

signal_received = sig;

1102

1188

int old_errno = errno;

1103

1189

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1190

if(simple_poll != NULL){

1191

avahi_simple_poll_quit(simple_poll);

1106

1192

}

1107

1193

errno = old_errno;

1108

1194

}

1109

1195

1196

__attribute__((nonnull, warn_unused_result))

1110

1197

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

1111

1198

int ret;

1199

error_t ret_errno;

1112

1200

1113

1201

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

1114

1202

if(s < 0){

1203

ret_errno = errno;

1115

1204

perror_plus("socket");

1205

errno = ret_errno;

1116

1206

return false;

1117

1207

}

1118

1208

strcpy(ifr->ifr_name, ifname);

1119

1209

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1210

if(ret == -1){

1121

1211

if(debug){

1212

ret_errno = errno;

1122

1213

perror_plus("ioctl SIOCGIFFLAGS");

1214

errno = ret_errno;

1123

1215

}

1124

1216

return false;

1125

1217

}

1126

1218

return true;

1127

1219

}

1128

1220

1221

__attribute__((nonnull, warn_unused_result))

1129

1222

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

1130

1223

1131

1224

/* Reject the loopback device */

1173

1266

* corresponds to an acceptable network device.

1174

1267

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

1175

1268

*/

1269

__attribute__((nonnull, warn_unused_result))

1176

1270

int good_interface(const struct dirent *if_entry){

1177

1271

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

1178

1272

return 0;

1194

1288

}

1195

1289

1196

1290

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

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

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

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

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1291

* This function determines if a network interface is up.

1292

*/

1293

__attribute__((nonnull, warn_unused_result))

1294

bool interface_is_up(const char *interface){

1295

struct ifreq ifr;

1296

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

1297

if(debug){

1298

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

1299

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

1300

}

1301

return false;

1302

}

1303

1304

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

1305

}

1306

1307

/*

1308

* This function determines if a network interface is running

1309

*/

1310

__attribute__((nonnull, warn_unused_result))

1311

bool interface_is_running(const char *interface){

1312

struct ifreq ifr;

1313

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

1314

if(debug){

1315

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

1316

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

1317

}

1318

return false;

1319

}

1320

1321

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

1322

}

1323

1324

__attribute__((nonnull, pure, warn_unused_result))

1239

1325

int notdotentries(const struct dirent *direntry){

1240

1326

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

1241

1327

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

1248

1334

}

1249

1335

1250

1336

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

1337

__attribute__((nonnull, warn_unused_result))

1251

1338

int runnable_hook(const struct dirent *direntry){

1252

1339

int ret;

1253

1340

size_t sret;

1261

1348

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

1262

1349

"abcdefghijklmnopqrstuvwxyz"

1263

1350

"0123456789"

1264

"_-");

1351

"_.-");

1265

1352

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

1266

1353

/* Contains non-allowed characters */

1267

1354

if(debug){

1271

1358

return 0;

1272

1359

}

1273

1360

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1361

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

1282

1362

if(ret == -1){

1283

1363

if(debug){

1284

1364

perror_plus("Could not stat hook");

1301

1381

}

1302

1382

return 0;

1303

1383

}

1384

if(debug){

1385

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1386

direntry->d_name);

1387

}

1304

1388

return 1;

1305

1389

}

1306

1390

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1308

1394

int ret;

1309

1395

struct timespec now;

1310

1396

struct timespec waited_time;

1311

1397

intmax_t block_time;

1312

1398

1313

1399

while(true){

1314

if(mc.current_server == NULL){

1315

if (debug){

1400

if(mc->current_server == NULL){

1401

if(debug){

1316

1402

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

1317

1403

" No timeout!\n");

1318

1404

}

1319

1405

ret = avahi_simple_poll_iterate(s, -1);

1320

1406

} else {

1321

if (debug){

1407

if(debug){

1322

1408

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

1323

1409

" it, or wait\n");

1324

1410

}

1331

1417

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

1332

1418

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

1333

1419

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

1420

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

1335

1421

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

1422

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

1337

1423

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

1338

1424

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

1339

1425

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

1341

1427

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

1342

1428

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

1343

1429

1344

if (debug){

1430

if(debug){

1345

1431

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

1346

1432

block_time);

1347

1433

}

1348

1434

1349

1435

if(block_time <= 0){

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

1436

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

1437

mc->current_server->port,

1438

mc->current_server->if_index,

1439

mc->current_server->af, mc);

1354

1440

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

1441

avahi_simple_poll_quit(s);

1356

1442

return 0;

1357

1443

}

1358

1444

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

1445

&mc->current_server->last_seen);

1360

1446

if(ret == -1){

1361

1447

perror_plus("clock_gettime");

1362

1448

return -1;

1363

1449

}

1364

mc.current_server = mc.current_server->next;

1450

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

1365

1451

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

1366

1452

servers, but don't block */

1367

1453

}

1369

1455

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

1370

1456

}

1371

1457

if(ret != 0){

1372

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

1458

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

1373

1459

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

1374

1460

}

1375

1461

}

1376

1462

}

1377

1463

}

1378

1464

1379

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

1465

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

1466

__attribute__((warn_unused_result))

1467

error_t raise_privileges(void){

1468

error_t old_errno = errno;

1469

error_t ret_errno = 0;

1470

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

1471

ret_errno = errno;

1472

}

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

1477

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

1478

__attribute__((warn_unused_result))

1479

error_t raise_privileges_permanently(void){

1480

error_t old_errno = errno;

1481

error_t ret_errno = raise_privileges();

1482

if(ret_errno != 0){

1483

errno = old_errno;

1484

return ret_errno;

1485

}

1486

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

1487

ret_errno = errno;

1488

}

1489

errno = old_errno;

1490

return ret_errno;

1491

}

1492

1493

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

1494

__attribute__((warn_unused_result))

1495

error_t lower_privileges(void){

1496

error_t old_errno = errno;

1497

error_t ret_errno = 0;

1498

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

1499

ret_errno = errno;

1500

}

1501

errno = old_errno;

1502

return ret_errno;

1503

}

1504

1505

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1507

error_t lower_privileges_permanently(void){

1508

error_t old_errno = errno;

1509

error_t ret_errno = 0;

1510

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

1511

ret_errno = errno;

1512

}

1513

errno = old_errno;

1514

return ret_errno;

1515

}

1516

1517

__attribute__((nonnull))

1518

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

1380

1519

const float delay){

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

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

1385

alphasort);

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__ */

1386

1547

if(numhooks == -1){

1387

1548

perror_plus("scandir");

1388

} else {

1389

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

1390

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

1391

direntry = direntries[0];

1392

char *fullname = NULL;

1393

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

1394

if(ret < 0){

1549

return;

1550

}

1551

struct dirent *direntry;

1552

int ret;

1553

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

1554

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

1555

direntry = direntries[i];

1556

if(debug){

1557

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

1558

direntry->d_name);

1559

}

1560

pid_t hook_pid = fork();

1561

if(hook_pid == 0){

1562

/* Child */

1563

/* Raise privileges */

1564

errno = raise_privileges_permanently();

1565

if(errno != 0){

1566

perror_plus("Failed to raise privileges");

1567

_exit(EX_NOPERM);

1568

}

1569

/* Set group */

1570

errno = 0;

1571

ret = setgid(0);

1572

if(ret == -1){

1573

perror_plus("setgid");

1574

_exit(EX_NOPERM);

1575

}

1576

/* Reset supplementary groups */

1577

errno = 0;

1578

ret = setgroups(0, NULL);

1579

if(ret == -1){

1580

perror_plus("setgroups");

1581

_exit(EX_NOPERM);

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

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

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

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

1596

_exit(EX_OSERR);

1597

}

1598

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

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

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

1604

if(ret == -1){

1605

perror_plus("setenv");

1606

_exit(EX_OSERR);

1607

}

1608

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

1609

if(ret == -1){

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

perror_plus("setenv");

1616

_exit(EX_OSERR);

1617

}

1618

char *delaystring;

1619

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

1620

if(ret == -1){

1395

1621

perror_plus("asprintf");

1396

continue;

1622

_exit(EX_OSERR);

1397

1623

}

1398

pid_t hook_pid = fork();

1399

if(hook_pid == 0){

1400

/* Child */

1401

dup2(devnull, STDIN_FILENO);

1402

close(devnull);

1403

dup2(STDERR_FILENO, STDOUT_FILENO);

1404

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

1405

if(ret == -1){

1406

perror_plus("setenv");

1407

return false;

1408

}

1409

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

1410

if(ret == -1){

1411

perror_plus("setenv");

1412

return false;

1413

}

1414

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

1415

if(ret == -1){

1416

perror_plus("setenv");

1417

return false;

1418

}

1419

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

1420

if(ret == -1){

1421

perror_plus("setenv");

1422

return false;

1423

}

1424

char *delaystring;

1425

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

1426

if(ret == -1){

1427

perror_plus("asprintf");

1428

return false;

1429

}

1430

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

1431

if(ret == -1){

1432

free(delaystring);

1433

perror_plus("setenv");

1434

return false;

1435

}

1624

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

1625

if(ret == -1){

1436

1626

free(delaystring);

1437

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

1438

perror_plus("execl");

1439

} else {

1440

int status;

1441

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

1442

perror_plus("waitpid");

1443

free(fullname);

1444

continue;

1445

}

1446

if(WIFEXITED(status)){

1447

if(WEXITSTATUS(status) != 0){

1448

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

1449

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

1450

WEXITSTATUS(status));

1451

free(fullname);

1452

continue;

1453

}

1454

} else if(WIFSIGNALED(status)){

1455

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

1456

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

1457

WTERMSIG(status));

1458

free(fullname);

1459

continue;

1460

} else {

1461

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

1462

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

1463

free(fullname);

1464

continue;

1465

}

1466

}

1467

free(fullname);

1468

if(quit_now){

1469

break;

1470

}

1471

}

1472

close(devnull);

1473

}

1474

return true;

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

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

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

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

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

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

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

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

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

if(hook_pid == -1){

1654

perror_plus("fork");

1655

free(direntry);

1656

continue;

1657

}

1658

int status;

1659

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

1660

perror_plus("waitpid");

1661

free(direntry);

1662

continue;

1663

}

1664

if(WIFEXITED(status)){

1665

if(WEXITSTATUS(status) != 0){

1666

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

1667

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

1668

WEXITSTATUS(status));

1669

free(direntry);

1670

continue;

1671

}

1672

} else if(WIFSIGNALED(status)){

1673

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

1674

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

1675

WTERMSIG(status));

1676

free(direntry);

1677

continue;

1678

} else {

1679

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

1680

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

1681

free(direntry);

1682

continue;

1683

}

1684

}

1685

if(debug){

1686

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

1687

direntry->d_name);

1688

}

1689

free(direntry);

1690

}

1691

free(direntries);

1692

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

1693

perror_plus("close");

1694

} else {

1695

hookdir_fd = -1;

1696

}

1697

close(devnull);

1698

}

1699

1700

__attribute__((nonnull, warn_unused_result))

1701

error_t bring_up_interface(const char *const interface,

1702

const float delay){

1703

error_t old_errno = errno;

1704

int ret;

1705

struct ifreq network;

1706

unsigned int if_index = if_nametoindex(interface);

1707

if(if_index == 0){

1708

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

1709

errno = old_errno;

1710

return ENXIO;

1711

}

1712

1713

if(quit_now){

1714

errno = old_errno;

1715

return EINTR;

1716

}

1717

1718

if(not interface_is_up(interface)){

1719

error_t ret_errno = 0, ioctl_errno = 0;

1720

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

1721

ret_errno = errno;

1722

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

1723

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

1724

errno = old_errno;

1725

return ret_errno;

1726

}

1727

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

1728

1729

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

1730

if(sd == -1){

1731

ret_errno = errno;

1732

perror_plus("socket");

1733

errno = old_errno;

1734

return ret_errno;

1735

}

1736

1737

if(quit_now){

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

errno = old_errno;

1743

return EINTR;

1744

}

1745

1746

if(debug){

1747

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

1748

interface);

1749

}

1750

1751

/* Raise privileges */

1752

ret_errno = raise_privileges();

1753

if(ret_errno != 0){

1754

errno = ret_errno;

1755

perror_plus("Failed to raise privileges");

1756

}

1757

1758

#ifdef __linux__

1759

int ret_linux;

1760

bool restore_loglevel = false;

1761

if(ret_errno == 0){

1762

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1763

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

1764

ret_linux = klogctl(8, NULL, 5);

1765

if(ret_linux == -1){

1766

perror_plus("klogctl");

1767

} else {

1768

restore_loglevel = true;

1769

}

1770

}

1771

#endif /* __linux__ */

1772

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

1773

ioctl_errno = errno;

1774

#ifdef __linux__

1775

if(restore_loglevel){

1776

ret_linux = klogctl(7, NULL, 0);

1777

if(ret_linux == -1){

1778

perror_plus("klogctl");

1779

}

1780

}

1781

#endif /* __linux__ */

1782

1783

/* If raise_privileges() succeeded above */

1784

if(ret_errno == 0){

1785

/* Lower privileges */

1786

ret_errno = lower_privileges();

1787

if(ret_errno != 0){

1788

errno = ret_errno;

1789

perror_plus("Failed to lower privileges");

1790

}

1791

}

1792

1793

/* Close the socket */

1794

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

1795

if(ret == -1){

1796

perror_plus("close");

1797

}

1798

1799

if(ret_setflags == -1){

1800

errno = ioctl_errno;

1801

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1802

errno = old_errno;

1803

return ioctl_errno;

1804

}

1805

} else if(debug){

1806

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

1807

interface);

1808

}

1809

1810

/* Sleep checking until interface is running.

1811

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

1812

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

1813

if(interface_is_running(interface)){

1814

break;

1815

}

1816

struct timespec sleeptime = { .tv_nsec = 250000000 };

1817

ret = nanosleep(&sleeptime, NULL);

1818

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

1819

perror_plus("nanosleep");

1820

}

1821

}

1822

1823

errno = old_errno;

1824

return 0;

1825

}

1826

1827

__attribute__((nonnull, warn_unused_result))

1828

error_t take_down_interface(const char *const interface){

1829

error_t old_errno = errno;

1830

struct ifreq network;

1831

unsigned int if_index = if_nametoindex(interface);

1832

if(if_index == 0){

1833

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

1834

errno = old_errno;

1835

return ENXIO;

1836

}

1837

if(interface_is_up(interface)){

1838

error_t ret_errno = 0, ioctl_errno = 0;

1839

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

1840

ret_errno = errno;

1841

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

1842

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

1843

errno = old_errno;

1844

return ret_errno;

1845

}

1846

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

1847

1848

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

1849

if(sd == -1){

1850

ret_errno = errno;

1851

perror_plus("socket");

1852

errno = old_errno;

1853

return ret_errno;

1854

}

1855

1856

if(debug){

1857

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

1858

interface);

1859

}

1860

1861

/* Raise privileges */

1862

ret_errno = raise_privileges();

1863

if(ret_errno != 0){

1864

errno = ret_errno;

1865

perror_plus("Failed to raise privileges");

1866

}

1867

1868

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

1869

ioctl_errno = errno;

1870

1871

/* If raise_privileges() succeeded above */

1872

if(ret_errno == 0){

1873

/* Lower privileges */

1874

ret_errno = lower_privileges();

1875

if(ret_errno != 0){

1876

errno = ret_errno;

1877

perror_plus("Failed to lower privileges");

1878

}

1879

}

1880

1881

/* Close the socket */

1882

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

1883

if(ret == -1){

1884

perror_plus("close");

1885

}

1886

1887

if(ret_setflags == -1){

1888

errno = ioctl_errno;

1889

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1890

errno = old_errno;

1891

return ioctl_errno;

1892

}

1893

} else if(debug){

1894

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

1895

interface);

1896

}

1897

1898

errno = old_errno;

1899

return 0;

1475

1900

}

1476

1901

1477

1902

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

1903

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

1904

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

1905

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

1906

.interfaces = NULL, .interfaces_size = 0 };

1478

1907

AvahiSServiceBrowser *sb = NULL;

1479

int error;

1908

error_t ret_errno;

1480

1909

int ret;

1481

1910

intmax_t tmpmax;

1482

1911

char *tmp;

1483

1912

int exitcode = EXIT_SUCCESS;

1484

const char *interface = "";

1485

struct ifreq network;

1486

int sd = -1;

1487

bool take_down_interface = false;

1488

uid_t uid;

1489

gid_t gid;

1490

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

1491

bool tempdir_created = false;

1913

char *interfaces_to_take_down = NULL;

1914

size_t interfaces_to_take_down_size = 0;

1915

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

1916

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

1917

char *tempdir = NULL;

1492

1918

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1493

1919

const char *seckey = PATHDIR "/" SECKEY;

1494

1920

const char *pubkey = PATHDIR "/" PUBKEY;

1921

char *interfaces_hooks = NULL;

1495

1922

1496

1923

bool gnutls_initialized = false;

1497

1924

bool gpgme_initialized = false;

1559

1986

.group = 2 },

1560

1987

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

1561

1988

.arg = "SECONDS",

1562

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

1989

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

1563

1990

.group = 2 },

1564

1991

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

1565

1992

.arg = "DIR",

1588

2015

connect_to = arg;

1589

2016

break;

1590

2017

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

1591

interface = arg;

2018

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

2019

arg, (int)',');

2020

if(ret_errno != 0){

2021

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

2022

}

1592

2023

break;

1593

2024

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

1594

2025

seckey = arg;

1637

2068

argp_state_help(state, state->out_stream,

1638

2069

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1639

2070

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

1640

fprintf_plus(state->out_stream,

1641

"Mandos plugin mandos-client: ");

1642

2071

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

1643

2072

exit(argp_err_exit_status);

1644

2073

break;

1672

2101

{

1673

2102

/* Work around Debian bug #633582:

1674

2103

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

1675

struct stat st;

1676

1677

/* Re-raise priviliges */

1678

errno = 0;

1679

ret = seteuid(0);

1680

if(ret == -1){

1681

perror_plus("seteuid");

1682

}

1683

1684

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

1685

int seckey_fd = open(seckey, O_RDONLY);

1686

if(seckey_fd == -1){

1687

perror_plus("open");

1688

} else {

1689

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

1690

if(ret == -1){

1691

perror_plus("fstat");

1692

} else {

1693

if(S_ISREG(st.st_mode)

1694

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

1695

ret = fchown(seckey_fd, uid, gid);

1696

if(ret == -1){

1697

perror_plus("fchown");

1698

}

1699

}

1700

}

1701

TEMP_FAILURE_RETRY(close(seckey_fd));

1702

}

1703

}

1704

1705

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

1706

int pubkey_fd = open(pubkey, O_RDONLY);

1707

if(pubkey_fd == -1){

1708

perror_plus("open");

1709

} else {

1710

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

1711

if(ret == -1){

1712

perror_plus("fstat");

1713

} else {

1714

if(S_ISREG(st.st_mode)

1715

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

1716

ret = fchown(pubkey_fd, uid, gid);

1717

if(ret == -1){

1718

perror_plus("fchown");

1719

}

1720

}

1721

}

1722

TEMP_FAILURE_RETRY(close(pubkey_fd));

1723

}

1724

}

1725

1726

/* Lower privileges */

1727

errno = 0;

1728

ret = seteuid(uid);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2104

2105

/* Re-raise privileges */

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2109

perror_plus("Failed to raise privileges");

2110

} else {

2111

struct stat st;

2112

2113

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

2114

int seckey_fd = open(seckey, O_RDONLY);

2115

if(seckey_fd == -1){

2116

perror_plus("open");

2117

} else {

2118

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

2119

if(ret == -1){

2120

perror_plus("fstat");

2121

} else {

2122

if(S_ISREG(st.st_mode)

2123

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

2124

ret = fchown(seckey_fd, uid, gid);

2125

if(ret == -1){

2126

perror_plus("fchown");

2127

}

2128

}

2129

}

2130

TEMP_FAILURE_RETRY(close(seckey_fd));

2131

}

2132

}

2133

2134

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

2135

int pubkey_fd = open(pubkey, O_RDONLY);

2136

if(pubkey_fd == -1){

2137

perror_plus("open");

2138

} else {

2139

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

2140

if(ret == -1){

2141

perror_plus("fstat");

2142

} else {

2143

if(S_ISREG(st.st_mode)

2144

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

2145

ret = fchown(pubkey_fd, uid, gid);

2146

if(ret == -1){

2147

perror_plus("fchown");

2148

}

2149

}

2150

}

2151

TEMP_FAILURE_RETRY(close(pubkey_fd));

2152

}

2153

}

2154

2155

/* Lower privileges */

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2159

perror_plus("Failed to lower privileges");

2160

}

2161

}

2162

}

2163

2164

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

2165

{

2166

char *interface = NULL;

2167

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

2168

interface))){

2169

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

2170

and if_nametoindex(interface) == 0){

2171

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

2172

fprintf_plus(stderr, "Not using nonexisting interface"

2173

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

2174

}

2175

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

2176

interface = NULL;

2177

}

1731

2178

}

1732

2179

}

1733

2180

1734

2181

/* Run network hooks */

1735

2182

{

1736

/* Re-raise priviliges */

1737

errno = 0;

1738

ret = seteuid(0);

1739

if(ret == -1){

1740

perror_plus("seteuid");

1741

}

1742

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

1743

goto end;

1744

}

1745

/* Lower privileges */

1746

errno = 0;

1747

ret = seteuid(uid);

1748

if(ret == -1){

1749

perror_plus("seteuid");

1750

}

2183

if(mc.interfaces != NULL){

2184

interfaces_hooks = malloc(mc.interfaces_size);

2185

if(interfaces_hooks == NULL){

2186

perror_plus("malloc");

2187

goto end;

2188

}

2189

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

2190

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

2191

}

2192

run_network_hooks("start", interfaces_hooks != NULL ?

2193

interfaces_hooks : "", delay);

1751

2194

}

1752

2195

1753

2196

if(not debug){

1754

2197

avahi_set_log_function(empty_log);

1755

2198

}

1756

2199

1757

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

1758

struct dirent **direntries;

1759

/* First look for interfaces that are up */

1760

ret = scandir(sys_class_net, &direntries, up_interface,

1761

alphasort);

1762

if(ret == 0){

1763

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

1764

free(direntries);

1765

ret = scandir(sys_class_net, &direntries, good_interface,

1766

alphasort);

1767

}

1768

if(ret >= 1){

1769

/* Pick the first interface returned */

1770

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

1771

if(debug){

1772

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

1773

}

1774

if(interface == NULL){

1775

perror_plus("malloc");

1776

free(direntries);

1777

exitcode = EXIT_FAILURE;

1778

goto end;

1779

}

1780

free(direntries);

1781

} else {

1782

free(direntries);

1783

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

1784

exitcode = EXIT_FAILURE;

1785

goto end;

1786

}

1787

}

1788

1789

2200

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

1790

2201

from the signal handler */

1791

2202

/* Initialize the pseudo-RNG for Avahi */

1792

2203

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

1793

mc.simple_poll = avahi_simple_poll_new();

1794

if(mc.simple_poll == NULL){

2204

simple_poll = avahi_simple_poll_new();

2205

if(simple_poll == NULL){

1795

2206

fprintf_plus(stderr,

1796

2207

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

1797

2208

exitcode = EX_UNAVAILABLE;

1861

2272

}

1862

2273

}

1863

2274

1864

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

1865

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

1866

if_index = (AvahiIfIndex) if_nametoindex(interface);

1867

if(if_index == 0){

1868

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

1869

exitcode = EX_UNAVAILABLE;

1870

goto end;

1871

}

1872

1873

if(quit_now){

1874

goto end;

1875

}

1876

1877

/* Re-raise priviliges */

1878

errno = 0;

1879

ret = seteuid(0);

1880

if(ret == -1){

1881

perror_plus("seteuid");

1882

}

1883

1884

#ifdef __linux__

1885

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1886

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

1887

ret = klogctl(8, NULL, 5);

1888

bool restore_loglevel = true;

1889

if(ret == -1){

1890

restore_loglevel = false;

1891

perror_plus("klogctl");

1892

}

1893

#endif /* __linux__ */

1894

1895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1896

if(sd < 0){

1897

perror_plus("socket");

1898

exitcode = EX_OSERR;

1899

#ifdef __linux__

1900

if(restore_loglevel){

1901

ret = klogctl(7, NULL, 0);

1902

if(ret == -1){

1903

perror_plus("klogctl");

1904

}

1905

}

1906

#endif /* __linux__ */

1907

/* Lower privileges */

1908

errno = 0;

1909

ret = seteuid(uid);

1910

if(ret == -1){

1911

perror_plus("seteuid");

1912

}

1913

goto end;

1914

}

1915

strcpy(network.ifr_name, interface);

1916

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

1917

if(ret == -1){

1918

perror_plus("ioctl SIOCGIFFLAGS");

1919

#ifdef __linux__

1920

if(restore_loglevel){

1921

ret = klogctl(7, NULL, 0);

1922

if(ret == -1){

1923

perror_plus("klogctl");

1924

}

1925

}

1926

#endif /* __linux__ */

1927

exitcode = EX_OSERR;

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

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

1937

network.ifr_flags |= IFF_UP;

1938

take_down_interface = true;

1939

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

1940

if(ret == -1){

1941

take_down_interface = false;

1942

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1943

exitcode = EX_OSERR;

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

2275

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

2276

if(mc.interfaces == NULL){

2277

struct dirent **direntries = NULL;

2278

/* Look for any good interfaces */

2279

ret = scandir(sys_class_net, &direntries, good_interface,

2280

alphasort);

2281

if(ret >= 1){

2282

/* Add all found interfaces to interfaces list */

2283

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

2284

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

2285

direntries[i]->d_name);

2286

if(ret_errno != 0){

2287

errno = ret_errno;

2288

perror_plus("argz_add");

2289

free(direntries[i]);

2290

continue;

2291

}

2292

if(debug){

2293

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

2294

direntries[i]->d_name);

2295

}

2296

free(direntries[i]);

2297

}

2298

free(direntries);

2299

} else {

2300

if(ret == 0){

2301

free(direntries);

2302

}

2303

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

2304

exitcode = EXIT_FAILURE;

2305

goto end;

2306

}

2307

}

2308

2309

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

2310

{

2311

char *interface = NULL;

2312

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

2313

interface))){

2314

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

2315

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

2316

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

2317

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

2318

interface);

2319

interface = NULL;

2320

while((interface = argz_next(mc.interfaces,

2321

mc.interfaces_size, interface))){

2322

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

2323

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

2324

interface);

2325

interface = NULL;

1949

2326

}

1950

2327

}

1951

#endif /* __linux__ */

1952

/* Lower privileges */

1953

errno = 0;

1954

ret = seteuid(uid);

1955

if(ret == -1){

1956

perror_plus("seteuid");

1957

}

1958

goto end;

1959

}

1960

}

1961

/* Sleep checking until interface is running.

1962

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

1963

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

1964

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

1965

if(ret == -1){

1966

perror_plus("ioctl SIOCGIFFLAGS");

1967

} else if(network.ifr_flags & IFF_RUNNING){

1968

2328

break;

1969

2329

}

1970

struct timespec sleeptime = { .tv_nsec = 250000000 };

1971

ret = nanosleep(&sleeptime, NULL);

1972

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

1973

perror_plus("nanosleep");

1974

}

1975

}

1976

if(not take_down_interface){

1977

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

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

}

1983

#ifdef __linux__

1984

if(restore_loglevel){

1985

/* Restores kernel loglevel to default */

1986

ret = klogctl(7, NULL, 0);

1987

if(ret == -1){

1988

perror_plus("klogctl");

1989

}

1990

}

1991

#endif /* __linux__ */

1992

/* Lower privileges */

1993

errno = 0;

1994

/* Lower privileges */

1995

ret = seteuid(uid);

1996

if(ret == -1){

1997

perror_plus("seteuid");

1998

}

2330

bool interface_was_up = interface_is_up(interface);

2331

errno = bring_up_interface(interface, delay);

2332

if(not interface_was_up){

2333

if(errno != 0){

2334

perror_plus("Failed to bring up interface");

2335

} else {

2336

errno = argz_add(&interfaces_to_take_down,

2337

&interfaces_to_take_down_size,

2338

interface);

2339

if(errno != 0){

2340

perror_plus("argz_add");

2341

}

2342

}

2343

}

2344

}

2345

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

2346

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

2347

}

2348

}

2349

2350

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

2351

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

2352

if(debug){

2353

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

2354

mc.interfaces);

2355

}

2356

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

1999

2357

}

2000

2358

2001

2359

if(quit_now){

2002

2360

goto end;

2003

2361

}

2004

2362

2005

ret = init_gnutls_global(pubkey, seckey);

2363

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

2006

2364

if(ret == -1){

2007

2365

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

2008

2366

exitcode = EX_UNAVAILABLE;

2015

2373

goto end;

2016

2374

}

2017

2375

2018

if(mkdtemp(tempdir) == NULL){

2376

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

2377

tempdir = mkdtemp(run_tempdir);

2378

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

2379

if(debug){

2380

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

2381

run_tempdir, old_tempdir);

2382

}

2383

tempdir = mkdtemp(old_tempdir);

2384

}

2385

if(tempdir == NULL){

2019

2386

perror_plus("mkdtemp");

2020

2387

goto end;

2021

2388

}

2022

tempdir_created = true;

2023

2389

2024

2390

if(quit_now){

2025

2391

goto end;

2026

2392

}

2027

2393

2028

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

2394

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

2029

2395

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

2030

2396

exitcode = EX_UNAVAILABLE;

2031

2397

goto end;

2041

2407

/* Connect directly, do not use Zeroconf */

2042

2408

/* (Mainly meant for debugging) */

2043

2409

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

2410

2044

2411

if(address == NULL){

2045

2412

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

2046

2413

exitcode = EX_USAGE;

2051

2418

goto end;

2052

2419

}

2053

2420

2054

uint16_t port;

2421

in_port_t port;

2055

2422

errno = 0;

2056

2423

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

2057

2424

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

2058

or tmpmax != (uint16_t)tmpmax){

2425

or tmpmax != (in_port_t)tmpmax){

2059

2426

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

2060

2427

exitcode = EX_USAGE;

2061

2428

goto end;

2062

2429

}

2063

2430

2064

2431

if(quit_now){

2065

2432

goto end;

2066

2433

}

2067

2434

2068

port = (uint16_t)tmpmax;

2435

port = (in_port_t)tmpmax;

2069

2436

*address = '\0';

2070

2437

/* Colon in address indicates IPv6 */

2071

2438

int af;

2087

2454

}

2088

2455

2089

2456

while(not quit_now){

2090

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

2457

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

2458

&mc);

2091

2459

if(quit_now or ret == 0){

2092

2460

break;

2093

2461

}

2095

2463

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

2096

2464

(int)retry_interval);

2097

2465

}

2098

sleep((int)retry_interval);

2466

sleep((unsigned int)retry_interval);

2099

2467

}

2100

2468

2101

if (not quit_now){

2469

if(not quit_now){

2102

2470

exitcode = EXIT_SUCCESS;

2103

2471

}

2104

2472

2119

2487

config.publish_domain = 0;

2120

2488

2121

2489

/* Allocate a new server */

2122

mc.server = avahi_server_new(avahi_simple_poll_get

2123

(mc.simple_poll), &config, NULL,

2124

NULL, &error);

2490

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2491

&config, NULL, NULL, &ret_errno);

2125

2492

2126

2493

/* Free the Avahi configuration data */

2127

2494

avahi_server_config_free(&config);

2130

2497

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

2131

2498

if(mc.server == NULL){

2132

2499

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

2133

avahi_strerror(error));

2500

avahi_strerror(ret_errno));

2134

2501

exitcode = EX_UNAVAILABLE;

2135

2502

goto end;

2136

2503

}

2142

2509

/* Create the Avahi service browser */

2143

2510

sb = avahi_s_service_browser_new(mc.server, if_index,

2144

2511

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2145

NULL, 0, browse_callback, NULL);

2512

NULL, 0, browse_callback,

2513

(void *)&mc);

2146

2514

if(sb == NULL){

2147

2515

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

2148

2516

avahi_strerror(avahi_server_errno(mc.server)));

2159

2527

if(debug){

2160

2528

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

2161

2529

}

2162

2163

ret = avahi_loop_with_timeout(mc.simple_poll,

2164

(int)(retry_interval * 1000));

2530

2531

ret = avahi_loop_with_timeout(simple_poll,

2532

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

2165

2533

if(debug){

2166

2534

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

2167

2535

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

2174

2542

}

2175

2543

2176

2544

/* Cleanup things */

2545

free(mc.interfaces);

2546

2177

2547

if(sb != NULL)

2178

2548

avahi_s_service_browser_free(sb);

2179

2549

2180

2550

if(mc.server != NULL)

2181

2551

avahi_server_free(mc.server);

2182

2552

2183

if(mc.simple_poll != NULL)

2184

avahi_simple_poll_free(mc.simple_poll);

2553

if(simple_poll != NULL)

2554

avahi_simple_poll_free(simple_poll);

2185

2555

2186

2556

if(gnutls_initialized){

2187

2557

gnutls_certificate_free_credentials(mc.cred);

2192

2562

if(gpgme_initialized){

2193

2563

gpgme_release(mc.ctx);

2194

2564

}

2195

2565

2196

2566

/* Cleans up the circular linked list of Mandos servers the client

2197

2567

has seen */

2198

2568

if(mc.current_server != NULL){

2199

2569

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

2200

2570

while(mc.current_server != NULL){

2201

2571

server *next = mc.current_server->next;

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic push

2574

#pragma GCC diagnostic ignored "-Wcast-qual"

2575

#endif

2576

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

2577

#ifdef __GNUC__

2578

#pragma GCC diagnostic pop

2579

#endif

2202

2580

free(mc.current_server);

2203

2581

mc.current_server = next;

2204

2582

}

2205

2583

}

2206

2584

2207

/* Re-raise priviliges */

2585

/* Re-raise privileges */

2208

2586

{

2209

errno = 0;

2210

ret = seteuid(0);

2211

if(ret == -1){

2212

perror_plus("seteuid");

2213

}

2214

/* Run network hooks */

2215

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

2216

goto end;

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2217

2614

}

2218

2615

2219

/* Take down the network interface */

2220

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

2221

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

2222

if(ret == -1){

2223

perror_plus("ioctl SIOCGIFFLAGS");

2224

} else if(network.ifr_flags & IFF_UP){

2225

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

2226

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

2227

if(ret == -1){

2228

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2229

}

2230

}

2231

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

2232

if(ret == -1){

2233

perror_plus("close");

2234

}

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

2619

perror_plus("Failed to lower privileges permanently");

2235

2620

}

2236

2621

}

2237

/* Lower privileges permanently */

2238

errno = 0;

2239

ret = setuid(uid);

2240

if(ret == -1){

2241

perror_plus("setuid");

2242

}

2622

2623

free(interfaces_to_take_down);

2624

free(interfaces_hooks);

2243

2625

2244

2626

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

2245

if(tempdir_created){

2627

if(tempdir != NULL){

2246

2628

struct dirent **direntries = NULL;

2247

struct dirent *direntry = NULL;

2248

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

2249

alphasort);

2250

if (numentries > 0){

2251

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

2252

direntry = direntries[i];

2253

char *fullname = NULL;

2254

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

2255

direntry->d_name);

2256

if(ret < 0){

2257

perror_plus("asprintf");

2258

continue;

2259

}

2260

ret = remove(fullname);

2261

if(ret == -1){

2262

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

2263

strerror(errno));

2264

}

2265

free(fullname);

2629

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

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

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

2639

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

2640

alphasort);

2641

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

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

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

2649

if(ret == -1){

2650

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

2651

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

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

2266

2666

}

2267

}

2268

2269

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

2270

free(direntries);

2271

if (numentries == -1){

2272

perror_plus("scandir");

2273

}

2274

ret = rmdir(tempdir);

2275

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

2276

perror_plus("rmdir");

2667

TEMP_FAILURE_RETRY(close(tempdir_fd));

2277

2668

}

2278

2669

}

2279

2670