/mandos/release : revision 237.16.11

9

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

10

*

11

* Everything else is

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13

12

13

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*

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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 /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

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#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(),

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stdout, ferror() */

44

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

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stdout, ferror(), remove() */

44

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

45

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

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

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strtof(), abort() */

55

opendir(), DIR */

56

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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61

*/

63

62

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

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63

strtoimax() */

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

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

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program_invocation_short_name */

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

73

*/

74

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

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

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

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unlinkat() */

78

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

76

setgid(), pause() */

77

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

79

78

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

80

79

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

81

80

argp_state, struct argp,

88

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

89

88

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

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WEXITSTATUS(), WTERMSIG() */

91

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

92

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

95

argz_count() */

96

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

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EAI_SYSTEM, gai_strerror() */

98

90

99

91

#ifdef __linux__

100

92

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

142

134

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

143

135

char *connect_to = NULL;

144

136

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

uid_t uid = 65534;

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gid_t gid = 65534;

148

137

149

138

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

150

139

typedef struct server{

151

140

const char *ip;

152

in_port_t port;

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uint16_t port;

153

142

AvahiIfIndex if_index;

154

143

int af;

155

144

struct timespec last_seen;

159

148

160

149

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

161

150

typedef struct {

151

AvahiSimplePoll *simple_poll;

162

152

AvahiServer *server;

163

153

gnutls_certificate_credentials_t cred;

164

154

unsigned int dh_bits;

166

156

const char *priority;

167

157

gpgme_ctx_t ctx;

168

158

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

159

} mandos_context;

172

160

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

161

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

162

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

175

166

176

167

sig_atomic_t quit_now = 0;

177

168

int signal_received = 0;

178

169

179

170

/* Function to use when printing errors */

180

171

void perror_plus(const char *print_text){

181

int e = errno;

182

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

183

173

program_invocation_short_name);

184

errno = e;

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174

perror(print_text);

186

175

}

187

176

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

189

177

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

190

178

va_list ap;

191

179

va_start (ap, format);

192

180

193

181

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

194

182

program_invocation_short_name));

195

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

183

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

196

184

}

197

185

198

186

/*

200

188

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

201

189

* "buffer_length" is how much is already used.

202

190

*/

203

__attribute__((nonnull, warn_unused_result))

204

191

size_t incbuffer(char **buffer, size_t buffer_length,

205

192

size_t buffer_capacity){

206

193

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

194

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

195

if(buffer == NULL){

213

196

return 0;

214

197

}

215

*buffer = new_buf;

216

198

buffer_capacity += BUFFER_SIZE;

217

199

}

218

200

return buffer_capacity;

219

201

}

220

202

221

203

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

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

204

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

205

int af){

225

206

int ret;

226

207

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

227

208

if(new_server == NULL){

228

209

perror_plus("malloc");

229

return false;

210

return -1;

230

211

}

231

212

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

232

213

.port = port,

234

215

.af = af };

235

216

if(new_server->ip == NULL){

236

217

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

218

return -1;

253

219

}

254

220

/* Special case of first server */

255

if(*current_server == NULL){

221

if (mc.current_server == NULL){

256

222

new_server->next = new_server;

257

223

new_server->prev = new_server;

258

*current_server = new_server;

224

mc.current_server = new_server;

225

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

259

226

} else {

260

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

261

new_server->next = *current_server;

262

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

227

new_server->next = mc.current_server;

228

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

263

229

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

230

mc.current_server->prev = new_server;

231

}

232

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

233

if(ret == -1){

234

perror_plus("clock_gettime");

235

return -1;

236

}

237

return 0;

267

238

}

268

239

269

240

/*

270

241

* Initialize GPGME.

271

242

*/

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

243

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

244

const char *tempdir){

277

245

gpgme_error_t rc;

278

246

gpgme_engine_info_t engine_info;

279

247

248

280

249

/*

281

250

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

282

251

*/

283

bool import_key(const char * const filename){

252

bool import_key(const char *filename){

284

253

int ret;

285

254

int fd;

286

255

gpgme_data_t pgp_data;

298

267

return false;

299

268

}

300

269

301

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

270

rc = gpgme_op_import(mc.ctx, pgp_data);

302

271

if(rc != GPG_ERR_NO_ERROR){

303

272

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

304

273

gpgme_strsource(rc), gpgme_strerror(rc));

348

317

}

349

318

350

319

/* Create new GPGME "context" */

351

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

320

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

352

321

if(rc != GPG_ERR_NO_ERROR){

353

322

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

354

323

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

367

336

* Decrypt OpenPGP data.

368

337

* Returns -1 on error

369

338

*/

370

__attribute__((nonnull, warn_unused_result))

371

339

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

340

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

341

char **plaintext){

375

342

gpgme_data_t dh_crypto, dh_plain;

376

343

gpgme_error_t rc;

377

344

ssize_t ret;

403

370

404

371

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

405

372

data buffer */

406

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

373

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

407

374

if(rc != GPG_ERR_NO_ERROR){

408

375

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

409

376

gpgme_strsource(rc), gpgme_strerror(rc));

410

377

plaintext_length = -1;

411

378

if(debug){

412

379

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

380

result = gpgme_op_decrypt_result(mc.ctx);

414

381

if(result == NULL){

415

382

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

416

383

} else {

493

460

return plaintext_length;

494

461

}

495

462

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

499

466

if(ret == NULL)

500

467

ret = "(unknown)";

501

468

return ret;

502

469

}

503

470

504

471

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

472

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

507

473

const char* string){

508

474

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

509

475

}

510

476

511

__attribute__((nonnull, warn_unused_result))

512

477

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

478

const char *seckeyfilename){

515

479

int ret;

516

480

517

481

if(debug){

534

498

}

535

499

536

500

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

502

if(ret != GNUTLS_E_SUCCESS){

539

503

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

540

504

safer_gnutls_strerror(ret));

550

514

}

551

515

552

516

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

517

(mc.cred, pubkeyfilename, seckeyfilename,

554

518

GNUTLS_OPENPGP_FMT_BASE64);

555

519

if(ret != GNUTLS_E_SUCCESS){

556

520

fprintf_plus(stderr,

562

526

}

563

527

564

528

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

529

ret = gnutls_dh_params_init(&mc.dh_params);

566

530

if(ret != GNUTLS_E_SUCCESS){

567

531

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

532

" initialization: %s\n",

569

533

safer_gnutls_strerror(ret));

570

534

goto globalfail;

571

535

}

572

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

536

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

573

537

if(ret != GNUTLS_E_SUCCESS){

574

538

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

575

539

safer_gnutls_strerror(ret));

576

540

goto globalfail;

577

541

}

578

542

579

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

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

544

581

545

return 0;

582

546

583

547

globalfail:

584

548

585

gnutls_certificate_free_credentials(mc->cred);

549

gnutls_certificate_free_credentials(mc.cred);

586

550

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

551

gnutls_dh_params_deinit(mc.dh_params);

588

552

return -1;

589

553

}

590

554

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

555

static int init_gnutls_session(gnutls_session_t *session){

594

556

int ret;

595

557

/* GnuTLS session creation */

596

558

do {

608

570

{

609

571

const char *err;

610

572

do {

611

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

573

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

612

574

if(quit_now){

613

575

gnutls_deinit(*session);

614

576

return -1;

625

587

626

588

do {

627

589

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

590

mc.cred);

629

591

if(quit_now){

630

592

gnutls_deinit(*session);

631

593

return -1;

641

603

/* ignore client certificate if any. */

642

604

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

605

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

607

646

608

return 0;

647

609

}

651

613

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

652

614

653

615

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

655

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

616

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

656

617

AvahiIfIndex if_index,

657

int af, mandos_context *mc){

618

int af){

658

619

int ret, tcp_sd = -1;

659

620

ssize_t sret;

660

struct sockaddr_storage to;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

661

625

char *buffer = NULL;

662

626

char *decrypted_buffer = NULL;

663

627

size_t buffer_length = 0;

687

651

return -1;

688

652

}

689

653

690

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

691

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

692

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

693

bool match = false;

694

{

695

char *interface = NULL;

696

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

697

interface))){

698

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

699

match = true;

700

break;

701

}

702

}

703

}

704

if(not match){

705

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

706

connect to the server */

707

if(debug){

708

char interface[IF_NAMESIZE];

709

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

710

perror_plus("if_indextoname");

711

} else {

712

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

713

" \"%s\"\n",

714

if_indextoname((unsigned int)if_index,

715

interface));

716

}

717

}

718

return -1;

719

}

720

}

721

722

ret = init_gnutls_session(&session, mc);

654

ret = init_gnutls_session(&session);

723

655

if(ret != 0){

724

656

return -1;

725

657

}

726

658

727

659

if(debug){

728

660

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

729

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

661

PRIu16 "\n", ip, port);

730

662

}

731

663

732

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

744

676

745

677

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

746

678

if(af == AF_INET6){

747

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

748

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

679

to.in6.sin6_family = (sa_family_t)af;

680

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

749

681

} else { /* IPv4 */

750

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

751

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

682

to.in.sin_family = (sa_family_t)af;

683

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

752

684

}

753

685

if(ret < 0 ){

754

686

int e = errno;

763

695

goto mandos_end;

764

696

}

765

697

if(af == AF_INET6){

766

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

767

if(IN6_IS_ADDR_LINKLOCAL

768

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

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

769

705

if(if_index == AVAHI_IF_UNSPEC){

770

706

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

771

707

" incomplete without a network interface\n");

773

709

goto mandos_end;

774

710

}

775

711

/* Set the network interface number as scope */

776

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

712

to.in6.sin6_scope_id = (uint32_t)if_index;

777

713

}

778

714

} else {

779

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

715

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

716

-Wconversion and

717

-Wunreachable-code */

780

718

}

781

719

782

720

if(quit_now){

790

728

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

791

729

perror_plus("if_indextoname");

792

730

} else {

793

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

794

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

731

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

732

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

795

733

}

796

734

} else {

797

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

798

ip, (uintmax_t)port);

735

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

736

ip, port);

799

737

}

800

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

801

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

802

741

if(af == AF_INET6){

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

742

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

743

sizeof(addrstr));

807

744

} else {

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

745

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

746

sizeof(addrstr));

812

747

}

813

if(ret == EAI_SYSTEM){

814

perror_plus("getnameinfo");

815

} else if(ret != 0) {

816

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

817

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

818

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

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

819

754

}

820

755

}

821

756

825

760

}

826

761

827

762

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

763

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

830

764

} else {

831

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

832

sizeof(struct sockaddr_in));

765

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

833

766

}

834

767

if(ret < 0){

835

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

768

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

836

769

int e = errno;

837

770

perror_plus("connect");

838

771

errno = e;

884

817

goto mandos_end;

885

818

}

886

819

887

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

888

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

889

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

890

gnutls_transport_set_ptr(session,

891

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

892

822

893

823

if(quit_now){

894

824

errno = EINTR;

999

929

if(buffer_length > 0){

1000

930

ssize_t decrypted_buffer_size;

1001

931

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1002

&decrypted_buffer, mc);

932

&decrypted_buffer);

1003

933

if(decrypted_buffer_size >= 0){

1004

934

1005

935

written = 0;

1053

983

return retval;

1054

984

}

1055

985

1056

__attribute__((nonnull))

1057

986

static void resolve_callback(AvahiSServiceResolver *r,

1058

987

AvahiIfIndex interface,

1059

988

AvahiProtocol proto,

1067

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1068

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1069

998

flags,

1070

void *mc){

1071

if(r == NULL){

1072

return;

1073

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1074

1001

1075

1002

/* Called whenever a service has been resolved successfully or

1076

1003

timed out */

1077

1004

1078

1005

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1080

1006

return;

1081

1007

}

1082

1008

1086

1012

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

1087

1013

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

1088

1014

domain,

1089

avahi_strerror(avahi_server_errno

1090

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1091

1016

break;

1092

1017

1093

1018

case AVAHI_RESOLVER_FOUND:

1099

1024

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

1100

1025

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

1101

1026

}

1102

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

1103

interface,

1104

avahi_proto_to_af(proto),

1105

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1106

1029

if(ret == 0){

1107

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1108

1031

} else {

1109

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

1110

avahi_proto_to_af(proto),

1111

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

1112

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

1113

" list\n", name);

1114

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1115

1034

}

1116

1035

}

1117

1036

}

1127

1046

const char *domain,

1128

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1129

1048

flags,

1130

void *mc){

1131

if(b == NULL){

1132

return;

1133

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1134

1051

1135

1052

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

1136

1053

is removed from the LAN */

1144

1061

case AVAHI_BROWSER_FAILURE:

1145

1062

1146

1063

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

1147

avahi_strerror(avahi_server_errno

1148

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

1149

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1150

1066

return;

1151

1067

1152

1068

case AVAHI_BROWSER_NEW:

1155

1071

the callback function is called the Avahi server will free the

1156

1072

resolver for us. */

1157

1073

1158

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

1159

interface, protocol, name, type,

1160

domain, protocol, 0,

1161

resolve_callback, mc) == NULL)

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1162

1077

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

1163

1078

" %s\n", name,

1164

avahi_strerror(avahi_server_errno

1165

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1166

1080

break;

1167

1081

1168

1082

case AVAHI_BROWSER_REMOVE:

1187

1101

signal_received = sig;

1188

1102

int old_errno = errno;

1189

1103

/* set main loop to exit */

1190

if(simple_poll != NULL){

1191

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1192

1106

}

1193

1107

errno = old_errno;

1194

1108

}

1195

1109

1196

__attribute__((nonnull, warn_unused_result))

1197

1110

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

1198

1111

int ret;

1199

error_t ret_errno;

1200

1112

1201

1113

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

1202

1114

if(s < 0){

1203

ret_errno = errno;

1204

1115

perror_plus("socket");

1205

errno = ret_errno;

1206

1116

return false;

1207

1117

}

1208

1118

strcpy(ifr->ifr_name, ifname);

1209

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1210

1120

if(ret == -1){

1211

1121

if(debug){

1212

ret_errno = errno;

1213

1122

perror_plus("ioctl SIOCGIFFLAGS");

1214

errno = ret_errno;

1215

1123

}

1216

1124

return false;

1217

1125

}

1218

1126

return true;

1219

1127

}

1220

1128

1221

__attribute__((nonnull, warn_unused_result))

1222

1129

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

1223

1130

1224

1131

/* Reject the loopback device */

1266

1173

* corresponds to an acceptable network device.

1267

1174

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

1268

1175

*/

1269

__attribute__((nonnull, warn_unused_result))

1270

1176

int good_interface(const struct dirent *if_entry){

1271

1177

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

1272

1178

return 0;

1288

1194

}

1289

1195

1290

1196

/*

1291

* This function determines if a network interface is up.

1292

*/

1293

__attribute__((nonnull, warn_unused_result))

1294

bool interface_is_up(const char *interface){

1295

struct ifreq ifr;

1296

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

1297

if(debug){

1298

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

1299

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

1300

}

1301

return false;

1302

}

1303

1304

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

1305

}

1306

1307

/*

1308

* This function determines if a network interface is running

1309

*/

1310

__attribute__((nonnull, warn_unused_result))

1311

bool interface_is_running(const char *interface){

1312

struct ifreq ifr;

1313

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

1314

if(debug){

1315

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

1316

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

1317

}

1318

return false;

1319

}

1320

1321

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

1322

}

1323

1324

__attribute__((nonnull, pure, warn_unused_result))

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

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

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

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

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1325

1239

int notdotentries(const struct dirent *direntry){

1326

1240

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

1327

1241

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

1334

1248

}

1335

1249

1336

1250

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

1337

__attribute__((nonnull, warn_unused_result))

1338

1251

int runnable_hook(const struct dirent *direntry){

1339

1252

int ret;

1340

1253

size_t sret;

1348

1261

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

1349

1262

"abcdefghijklmnopqrstuvwxyz"

1350

1263

"0123456789"

1351

"_.-");

1264

"_-");

1352

1265

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

1353

1266

/* Contains non-allowed characters */

1354

1267

if(debug){

1358

1271

return 0;

1359

1272

}

1360

1273

1361

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

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1362

1282

if(ret == -1){

1363

1283

if(debug){

1364

1284

perror_plus("Could not stat hook");

1381

1301

}

1382

1302

return 0;

1383

1303

}

1384

if(debug){

1385

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

1386

direntry->d_name);

1387

}

1388

1304

return 1;

1389

1305

}

1390

1306

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1394

1308

int ret;

1395

1309

struct timespec now;

1396

1310

struct timespec waited_time;

1397

1311

intmax_t block_time;

1398

1312

1399

1313

while(true){

1400

if(mc->current_server == NULL){

1401

if(debug){

1314

if(mc.current_server == NULL){

1315

if (debug){

1402

1316

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

1403

1317

" No timeout!\n");

1404

1318

}

1405

1319

ret = avahi_simple_poll_iterate(s, -1);

1406

1320

} else {

1407

if(debug){

1321

if (debug){

1408

1322

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

1409

1323

" it, or wait\n");

1410

1324

}

1417

1331

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

1418

1332

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

1419

1333

waited_time.tv_sec = (now.tv_sec

1420

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

1334

- mc.current_server->last_seen.tv_sec);

1421

1335

waited_time.tv_nsec = (now.tv_nsec

1422

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

1336

- mc.current_server->last_seen.tv_nsec);

1423

1337

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

1424

1338

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

1425

1339

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

1427

1341

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

1428

1342

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

1429

1343

1430

if(debug){

1344

if (debug){

1431

1345

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

1432

1346

block_time);

1433

1347

}

1434

1348

1435

1349

if(block_time <= 0){

1436

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

1437

mc->current_server->port,

1438

mc->current_server->if_index,

1439

mc->current_server->af, mc);

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);

1440

1354

if(ret == 0){

1441

avahi_simple_poll_quit(s);

1355

avahi_simple_poll_quit(mc.simple_poll);

1442

1356

return 0;

1443

1357

}

1444

1358

ret = clock_gettime(CLOCK_MONOTONIC,

1445

&mc->current_server->last_seen);

1359

&mc.current_server->last_seen);

1446

1360

if(ret == -1){

1447

1361

perror_plus("clock_gettime");

1448

1362

return -1;

1449

1363

}

1450

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

1364

mc.current_server = mc.current_server->next;

1451

1365

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

1452

1366

servers, but don't block */

1453

1367

}

1455

1369

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

1456

1370

}

1457

1371

if(ret != 0){

1458

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

1372

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

1459

1373

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

1460

1374

}

1461

1375

}

1462

1376

}

1463

1377

}

1464

1378

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,

1379

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

1519

1380

const float delay){

1520

struct dirent **direntries = NULL;

1521

if(hookdir_fd == -1){

1522

hookdir_fd = open(hookdir, O_RDONLY);

1523

if(hookdir_fd == -1){

1524

if(errno == ENOENT){

1525

if(debug){

1526

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

1527

" found\n", hookdir);

1528

}

1529

} else {

1530

perror_plus("open");

1531

}

1532

return;

1533

}

1534

}

1535

#ifdef __GLIBC__

1536

#if __GLIBC_PREREQ(2, 15)

1537

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

1538

runnable_hook, alphasort);

1539

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

1540

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

1541

alphasort);

1542

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

1543

#else /* not __GLIBC__ */

1544

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

1545

alphasort);

1546

#endif /* not __GLIBC__ */

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

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

1385

alphasort);

1547

1386

if(numhooks == -1){

1548

1387

perror_plus("scandir");

1549

return;

1550

}

1551

struct dirent *direntry;

1552

int ret;

1553

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

1554

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

1555

direntry = direntries[i];

1556

if(debug){

1557

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

1558

direntry->d_name);

1559

}

1560

pid_t hook_pid = fork();

1561

if(hook_pid == 0){

1562

/* Child */

1563

/* Raise privileges */

1564

errno = raise_privileges_permanently();

1565

if(errno != 0){

1566

perror_plus("Failed to raise privileges");

1567

_exit(EX_NOPERM);

1568

}

1569

/* Set group */

1570

errno = 0;

1571

ret = setgid(0);

1572

if(ret == -1){

1573

perror_plus("setgid");

1574

_exit(EX_NOPERM);

1575

}

1576

/* Reset supplementary groups */

1577

errno = 0;

1578

ret = setgroups(0, NULL);

1579

if(ret == -1){

1580

perror_plus("setgroups");

1581

_exit(EX_NOPERM);

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

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

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

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

1596

_exit(EX_OSERR);

1597

}

1598

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

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

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

1604

if(ret == -1){

1605

perror_plus("setenv");

1606

_exit(EX_OSERR);

1607

}

1608

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

1609

if(ret == -1){

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

perror_plus("setenv");

1616

_exit(EX_OSERR);

1617

}

1618

char *delaystring;

1619

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

1620

if(ret == -1){

1388

} else {

1389

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

1390

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

1391

direntry = direntries[i];

1392

char *fullname = NULL;

1393

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

1394

if(ret < 0){

1621

1395

perror_plus("asprintf");

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

if(ret == -1){

1396

continue;

1397

}

1398

if(debug){

1399

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

1400

direntry->d_name);

1401

}

1402

pid_t hook_pid = fork();

1403

if(hook_pid == 0){

1404

/* Child */

1405

dup2(devnull, STDIN_FILENO);

1406

close(devnull);

1407

dup2(STDERR_FILENO, STDOUT_FILENO);

1408

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

1409

if(ret == -1){

1410

perror_plus("setenv");

1411

return false;

1412

}

1413

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

1414

if(ret == -1){

1415

perror_plus("setenv");

1416

return false;

1417

}

1418

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

1419

if(ret == -1){

1420

perror_plus("setenv");

1421

return false;

1422

}

1423

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

1424

if(ret == -1){

1425

perror_plus("setenv");

1426

return false;

1427

}

1428

char *delaystring;

1429

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

1430

if(ret == -1){

1431

perror_plus("asprintf");

1432

return false;

1433

}

1434

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

1435

if(ret == -1){

1436

free(delaystring);

1437

perror_plus("setenv");

1438

return false;

1439

}

1626

1440

free(delaystring);

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

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

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

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

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

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

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

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

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

int status;

1654

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

1655

perror_plus("waitpid");

1656

free(direntry);

1657

continue;

1658

}

1659

if(WIFEXITED(status)){

1660

if(WEXITSTATUS(status) != 0){

1661

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

1662

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

1663

WEXITSTATUS(status));

1664

free(direntry);

1665

continue;

1666

}

1667

} else if(WIFSIGNALED(status)){

1668

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

1669

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

1670

WTERMSIG(status));

1671

free(direntry);

1672

continue;

1673

} else {

1674

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

1675

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

1676

free(direntry);

1677

continue;

1678

}

1679

}

1680

if(debug){

1681

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

1682

direntry->d_name);

1683

}

1684

free(direntry);

1685

}

1686

free(direntries);

1687

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

1688

perror_plus("close");

1689

} else {

1690

hookdir_fd = -1;

1691

}

1692

close(devnull);

1693

}

1694

1695

__attribute__((nonnull, warn_unused_result))

1696

error_t bring_up_interface(const char *const interface,

1697

const float delay){

1698

error_t old_errno = errno;

1699

int ret;

1700

struct ifreq network;

1701

unsigned int if_index = if_nametoindex(interface);

1702

if(if_index == 0){

1703

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

1704

errno = old_errno;

1705

return ENXIO;

1706

}

1707

1708

if(quit_now){

1709

errno = old_errno;

1710

return EINTR;

1711

}

1712

1713

if(not interface_is_up(interface)){

1714

error_t ret_errno = 0, ioctl_errno = 0;

1715

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

1716

ret_errno = errno;

1717

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

1718

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

1719

errno = old_errno;

1720

return ret_errno;

1721

}

1722

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

1723

1724

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

1725

if(sd == -1){

1726

ret_errno = errno;

1727

perror_plus("socket");

1728

errno = old_errno;

1729

return ret_errno;

1730

}

1731

1732

if(quit_now){

1733

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

1734

if(ret == -1){

1735

perror_plus("close");

1736

}

1737

errno = old_errno;

1738

return EINTR;

1739

}

1740

1741

if(debug){

1742

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

1743

interface);

1744

}

1745

1746

/* Raise privileges */

1747

ret_errno = raise_privileges();

1748

if(ret_errno != 0){

1749

errno = ret_errno;

1750

perror_plus("Failed to raise privileges");

1751

}

1752

1753

#ifdef __linux__

1754

int ret_linux;

1755

bool restore_loglevel = false;

1756

if(ret_errno == 0){

1757

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1758

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

1759

ret_linux = klogctl(8, NULL, 5);

1760

if(ret_linux == -1){

1761

perror_plus("klogctl");

1762

} else {

1763

restore_loglevel = true;

1764

}

1765

}

1766

#endif /* __linux__ */

1767

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

1768

ioctl_errno = errno;

1769

#ifdef __linux__

1770

if(restore_loglevel){

1771

ret_linux = klogctl(7, NULL, 0);

1772

if(ret_linux == -1){

1773

perror_plus("klogctl");

1774

}

1775

}

1776

#endif /* __linux__ */

1777

1778

/* If raise_privileges() succeeded above */

1779

if(ret_errno == 0){

1780

/* Lower privileges */

1781

ret_errno = lower_privileges();

1782

if(ret_errno != 0){

1783

errno = ret_errno;

1784

perror_plus("Failed to lower privileges");

1785

}

1786

}

1787

1788

/* Close the socket */

1789

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

1790

if(ret == -1){

1791

perror_plus("close");

1792

}

1793

1794

if(ret_setflags == -1){

1795

errno = ioctl_errno;

1796

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1797

errno = old_errno;

1798

return ioctl_errno;

1799

}

1800

} else if(debug){

1801

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

1802

interface);

1803

}

1804

1805

/* Sleep checking until interface is running.

1806

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

1807

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

1808

if(interface_is_running(interface)){

1809

break;

1810

}

1811

struct timespec sleeptime = { .tv_nsec = 250000000 };

1812

ret = nanosleep(&sleeptime, NULL);

1813

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

1814

perror_plus("nanosleep");

1815

}

1816

}

1817

1818

errno = old_errno;

1819

return 0;

1820

}

1821

1822

__attribute__((nonnull, warn_unused_result))

1823

error_t take_down_interface(const char *const interface){

1824

error_t old_errno = errno;

1825

struct ifreq network;

1826

unsigned int if_index = if_nametoindex(interface);

1827

if(if_index == 0){

1828

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

1829

errno = old_errno;

1830

return ENXIO;

1831

}

1832

if(interface_is_up(interface)){

1833

error_t ret_errno = 0, ioctl_errno = 0;

1834

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

1835

ret_errno = errno;

1836

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

1837

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

1838

errno = old_errno;

1839

return ret_errno;

1840

}

1841

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

1842

1843

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

1844

if(sd == -1){

1845

ret_errno = errno;

1846

perror_plus("socket");

1847

errno = old_errno;

1848

return ret_errno;

1849

}

1850

1851

if(debug){

1852

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

1853

interface);

1854

}

1855

1856

/* Raise privileges */

1857

ret_errno = raise_privileges();

1858

if(ret_errno != 0){

1859

errno = ret_errno;

1860

perror_plus("Failed to raise privileges");

1861

}

1862

1863

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

1864

ioctl_errno = errno;

1865

1866

/* If raise_privileges() succeeded above */

1867

if(ret_errno == 0){

1868

/* Lower privileges */

1869

ret_errno = lower_privileges();

1870

if(ret_errno != 0){

1871

errno = ret_errno;

1872

perror_plus("Failed to lower privileges");

1873

}

1874

}

1875

1876

/* Close the socket */

1877

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

1878

if(ret == -1){

1879

perror_plus("close");

1880

}

1881

1882

if(ret_setflags == -1){

1883

errno = ioctl_errno;

1884

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1885

errno = old_errno;

1886

return ioctl_errno;

1887

}

1888

} else if(debug){

1889

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

1890

interface);

1891

}

1892

1893

errno = old_errno;

1894

return 0;

1441

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

1442

perror_plus("execl");

1443

} else {

1444

int status;

1445

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

1446

perror_plus("waitpid");

1447

free(fullname);

1448

continue;

1449

}

1450

if(WIFEXITED(status)){

1451

if(WEXITSTATUS(status) != 0){

1452

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

1453

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

1454

WEXITSTATUS(status));

1455

free(fullname);

1456

continue;

1457

}

1458

} else if(WIFSIGNALED(status)){

1459

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

1460

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

1461

WTERMSIG(status));

1462

free(fullname);

1463

continue;

1464

} else {

1465

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

1466

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

1467

free(fullname);

1468

continue;

1469

}

1470

}

1471

free(fullname);

1472

if(quit_now){

1473

break;

1474

}

1475

}

1476

close(devnull);

1477

}

1478

return true;

1895

1479

}

1896

1480

1897

1481

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

1898

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

1899

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

1900

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

1901

.interfaces = NULL, .interfaces_size = 0 };

1902

1482

AvahiSServiceBrowser *sb = NULL;

1903

error_t ret_errno;

1483

int error;

1904

1484

int ret;

1905

1485

intmax_t tmpmax;

1906

1486

char *tmp;

1907

1487

int exitcode = EXIT_SUCCESS;

1908

char *interfaces_to_take_down = NULL;

1909

size_t interfaces_to_take_down_size = 0;

1910

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

1911

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

1912

char *tempdir = NULL;

1488

const char *interface = "";

1489

struct ifreq network;

1490

int sd = -1;

1491

bool take_down_interface = false;

1492

uid_t uid;

1493

gid_t gid;

1494

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

1495

bool tempdir_created = false;

1913

1496

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1914

1497

const char *seckey = PATHDIR "/" SECKEY;

1915

1498

const char *pubkey = PATHDIR "/" PUBKEY;

1916

char *interfaces_hooks = NULL;

1917

1499

1918

1500

bool gnutls_initialized = false;

1919

1501

bool gpgme_initialized = false;

1981

1563

.group = 2 },

1982

1564

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

1983

1565

.arg = "SECONDS",

1984

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

1566

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

1985

1567

.group = 2 },

1986

1568

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

1987

1569

.arg = "DIR",

2010

1592

connect_to = arg;

2011

1593

break;

2012

1594

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

2013

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

2014

arg, (int)',');

2015

if(ret_errno != 0){

2016

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

2017

}

1595

interface = arg;

2018

1596

break;

2019

1597

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

2020

1598

seckey = arg;

2063

1641

argp_state_help(state, state->out_stream,

2064

1642

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2065

1643

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

1644

fprintf_plus(state->out_stream,

1645

"Mandos plugin mandos-client: ");

2066

1646

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

2067

1647

exit(argp_err_exit_status);

2068

1648

break;

2093

1673

}

2094

1674

}

2095

1675

2096

{

1676

if(getuid() == 0){

2097

1677

/* Work around Debian bug #633582:

2098

1678

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

2099

2100

/* Re-raise privileges */

2101

ret_errno = raise_privileges();

2102

if(ret_errno != 0){

2103

errno = ret_errno;

2104

perror_plus("Failed to raise privileges");

2105

} else {

2106

struct stat st;

2107

2108

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

2109

int seckey_fd = open(seckey, O_RDONLY);

2110

if(seckey_fd == -1){

2111

perror_plus("open");

2112

} else {

2113

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

2114

if(ret == -1){

2115

perror_plus("fstat");

2116

} else {

2117

if(S_ISREG(st.st_mode)

2118

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

2119

ret = fchown(seckey_fd, uid, gid);

2120

if(ret == -1){

2121

perror_plus("fchown");

2122

}

2123

}

2124

}

2125

TEMP_FAILURE_RETRY(close(seckey_fd));

2126

}

2127

}

2128

2129

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

2130

int pubkey_fd = open(pubkey, O_RDONLY);

2131

if(pubkey_fd == -1){

2132

perror_plus("open");

2133

} else {

2134

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

2135

if(ret == -1){

2136

perror_plus("fstat");

2137

} else {

2138

if(S_ISREG(st.st_mode)

2139

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

2140

ret = fchown(pubkey_fd, uid, gid);

2141

if(ret == -1){

2142

perror_plus("fchown");

2143

}

2144

}

2145

}

2146

TEMP_FAILURE_RETRY(close(pubkey_fd));

2147

}

2148

}

2149

2150

/* Lower privileges */

2151

ret_errno = lower_privileges();

2152

if(ret_errno != 0){

2153

errno = ret_errno;

2154

perror_plus("Failed to lower privileges");

2155

}

2156

}

2157

}

2158

2159

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

2160

{

2161

char *interface = NULL;

2162

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

2163

interface))){

2164

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

2165

and if_nametoindex(interface) == 0){

2166

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

2167

fprintf_plus(stderr, "Not using nonexisting interface"

2168

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

2169

}

2170

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

2171

interface = NULL;

2172

}

1679

struct stat st;

1680

1681

/* Re-raise priviliges */

1682

errno = 0;

1683

ret = seteuid(0);

1684

if(ret == -1){

1685

perror_plus("seteuid");

1686

}

1687

1688

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

1689

int seckey_fd = open(seckey, O_RDONLY);

1690

if(seckey_fd == -1){

1691

perror_plus("open");

1692

} else {

1693

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

1694

if(ret == -1){

1695

perror_plus("fstat");

1696

} else {

1697

if(S_ISREG(st.st_mode)

1698

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

1699

ret = fchown(seckey_fd, uid, gid);

1700

if(ret == -1){

1701

perror_plus("fchown");

1702

}

1703

}

1704

}

1705

TEMP_FAILURE_RETRY(close(seckey_fd));

1706

}

1707

}

1708

1709

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

1710

int pubkey_fd = open(pubkey, O_RDONLY);

1711

if(pubkey_fd == -1){

1712

perror_plus("open");

1713

} else {

1714

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

1715

if(ret == -1){

1716

perror_plus("fstat");

1717

} else {

1718

if(S_ISREG(st.st_mode)

1719

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

1720

ret = fchown(pubkey_fd, uid, gid);

1721

if(ret == -1){

1722

perror_plus("fchown");

1723

}

1724

}

1725

}

1726

TEMP_FAILURE_RETRY(close(pubkey_fd));

1727

}

1728

}

1729

1730

/* Lower privileges */

1731

errno = 0;

1732

ret = seteuid(uid);

1733

if(ret == -1){

1734

perror_plus("seteuid");

2173

1735

}

2174

1736

}

2175

1737

2176

1738

/* Run network hooks */

2177

1739

{

2178

if(mc.interfaces != NULL){

2179

interfaces_hooks = malloc(mc.interfaces_size);

2180

if(interfaces_hooks == NULL){

2181

perror_plus("malloc");

2182

goto end;

2183

}

2184

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

2185

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

2186

}

2187

run_network_hooks("start", interfaces_hooks != NULL ?

2188

interfaces_hooks : "", delay);

1740

if(getuid() == 0){

1741

/* Re-raise priviliges */

1742

errno = 0;

1743

ret = seteuid(0);

1744

if(ret == -1){

1745

perror_plus("seteuid");

1746

}

1747

}

1748

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

1749

goto end;

1750

}

1751

if(getuid() == 0){

1752

/* Lower privileges */

1753

errno = 0;

1754

ret = seteuid(uid);

1755

if(ret == -1){

1756

perror_plus("seteuid");

1757

}

1758

}

2189

1759

}

2190

1760

2191

1761

if(not debug){

2192

1762

avahi_set_log_function(empty_log);

2193

1763

}

2194

1764

1765

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

1766

struct dirent **direntries;

1767

/* First look for interfaces that are up */

1768

ret = scandir(sys_class_net, &direntries, up_interface,

1769

alphasort);

1770

if(ret == 0){

1771

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

1772

free(direntries);

1773

ret = scandir(sys_class_net, &direntries, good_interface,

1774

alphasort);

1775

}

1776

if(ret >= 1){

1777

/* Pick the first interface returned */

1778

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

1779

if(debug){

1780

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

1781

}

1782

if(interface == NULL){

1783

perror_plus("malloc");

1784

free(direntries);

1785

exitcode = EXIT_FAILURE;

1786

goto end;

1787

}

1788

free(direntries);

1789

} else {

1790

free(direntries);

1791

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

1792

exitcode = EXIT_FAILURE;

1793

goto end;

1794

}

1795

}

1796

2195

1797

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

2196

1798

from the signal handler */

2197

1799

/* Initialize the pseudo-RNG for Avahi */

2198

1800

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

2199

simple_poll = avahi_simple_poll_new();

2200

if(simple_poll == NULL){

1801

mc.simple_poll = avahi_simple_poll_new();

1802

if(mc.simple_poll == NULL){

2201

1803

fprintf_plus(stderr,

2202

1804

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

2203

1805

exitcode = EX_UNAVAILABLE;

2267

1869

}

2268

1870

}

2269

1871

2270

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

2271

if(mc.interfaces == NULL){

2272

struct dirent **direntries = NULL;

2273

/* Look for any good interfaces */

2274

ret = scandir(sys_class_net, &direntries, good_interface,

2275

alphasort);

2276

if(ret >= 1){

2277

/* Add all found interfaces to interfaces list */

2278

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

2279

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

2280

direntries[i]->d_name);

2281

if(ret_errno != 0){

2282

errno = ret_errno;

2283

perror_plus("argz_add");

2284

free(direntries[i]);

2285

continue;

2286

}

2287

if(debug){

2288

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

2289

direntries[i]->d_name);

2290

}

2291

free(direntries[i]);

2292

}

2293

free(direntries);

2294

} else {

2295

if(ret == 0){

2296

free(direntries);

2297

}

2298

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

2299

exitcode = EXIT_FAILURE;

2300

goto end;

2301

}

2302

}

2303

2304

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

2305

{

2306

char *interface = NULL;

2307

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

2308

interface))){

2309

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

2310

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

2311

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

2312

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

2313

interface);

2314

interface = NULL;

2315

while((interface = argz_next(mc.interfaces,

2316

mc.interfaces_size, interface))){

2317

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

2318

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

2319

interface);

2320

interface = NULL;

1872

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

1873

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

1874

if_index = (AvahiIfIndex) if_nametoindex(interface);

1875

if(if_index == 0){

1876

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

1877

exitcode = EX_UNAVAILABLE;

1878

goto end;

1879

}

1880

1881

if(quit_now){

1882

goto end;

1883

}

1884

1885

/* Re-raise priviliges */

1886

errno = 0;

1887

ret = seteuid(0);

1888

if(ret == -1){

1889

perror_plus("seteuid");

1890

}

1891

1892

#ifdef __linux__

1893

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1894

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

1895

ret = klogctl(8, NULL, 5);

1896

bool restore_loglevel = true;

1897

if(ret == -1){

1898

restore_loglevel = false;

1899

perror_plus("klogctl");

1900

}

1901

#endif /* __linux__ */

1902

1903

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1904

if(sd < 0){

1905

perror_plus("socket");

1906

exitcode = EX_OSERR;

1907

#ifdef __linux__

1908

if(restore_loglevel){

1909

ret = klogctl(7, NULL, 0);

1910

if(ret == -1){

1911

perror_plus("klogctl");

1912

}

1913

}

1914

#endif /* __linux__ */

1915

/* Lower privileges */

1916

errno = 0;

1917

ret = seteuid(uid);

1918

if(ret == -1){

1919

perror_plus("seteuid");

1920

}

1921

goto end;

1922

}

1923

strcpy(network.ifr_name, interface);

1924

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

1925

if(ret == -1){

1926

perror_plus("ioctl SIOCGIFFLAGS");

1927

#ifdef __linux__

1928

if(restore_loglevel){

1929

ret = klogctl(7, NULL, 0);

1930

if(ret == -1){

1931

perror_plus("klogctl");

1932

}

1933

}

1934

#endif /* __linux__ */

1935

exitcode = EX_OSERR;

1936

/* Lower privileges */

1937

errno = 0;

1938

ret = seteuid(uid);

1939

if(ret == -1){

1940

perror_plus("seteuid");

1941

}

1942

goto end;

1943

}

1944

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

1945

network.ifr_flags |= IFF_UP;

1946

take_down_interface = true;

1947

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

1948

if(ret == -1){

1949

take_down_interface = false;

1950

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1951

exitcode = EX_OSERR;

1952

#ifdef __linux__

1953

if(restore_loglevel){

1954

ret = klogctl(7, NULL, 0);

1955

if(ret == -1){

1956

perror_plus("klogctl");

2321

1957

}

2322

1958

}

1959

#endif /* __linux__ */

1960

/* Lower privileges */

1961

errno = 0;

1962

ret = seteuid(uid);

1963

if(ret == -1){

1964

perror_plus("seteuid");

1965

}

1966

goto end;

1967

}

1968

}

1969

/* Sleep checking until interface is running.

1970

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

1971

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

1972

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

1973

if(ret == -1){

1974

perror_plus("ioctl SIOCGIFFLAGS");

1975

} else if(network.ifr_flags & IFF_RUNNING){

2323

1976

break;

2324

1977

}

2325

bool interface_was_up = interface_is_up(interface);

2326

errno = bring_up_interface(interface, delay);

2327

if(not interface_was_up){

2328

if(errno != 0){

2329

perror_plus("Failed to bring up interface");

2330

} else {

2331

errno = argz_add(&interfaces_to_take_down,

2332

&interfaces_to_take_down_size,

2333

interface);

2334

if(errno != 0){

2335

perror_plus("argz_add");

2336

}

2337

}

2338

}

2339

}

2340

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

2341

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

2342

}

2343

}

2344

2345

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

2346

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

2347

if(debug){

2348

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

2349

mc.interfaces);

2350

}

2351

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

1978

struct timespec sleeptime = { .tv_nsec = 250000000 };

1979

ret = nanosleep(&sleeptime, NULL);

1980

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

1981

perror_plus("nanosleep");

1982

}

1983

}

1984

if(not take_down_interface){

1985

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

1986

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

1987

if(ret == -1){

1988

perror_plus("close");

1989

}

1990

}

1991

#ifdef __linux__

1992

if(restore_loglevel){

1993

/* Restores kernel loglevel to default */

1994

ret = klogctl(7, NULL, 0);

1995

if(ret == -1){

1996

perror_plus("klogctl");

1997

}

1998

}

1999

#endif /* __linux__ */

2000

/* Lower privileges */

2001

errno = 0;

2002

/* Lower privileges */

2003

ret = seteuid(uid);

2004

if(ret == -1){

2005

perror_plus("seteuid");

2006

}

2352

2007

}

2353

2008

2354

2009

if(quit_now){

2355

2010

goto end;

2356

2011

}

2357

2012

2358

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

2013

ret = init_gnutls_global(pubkey, seckey);

2359

2014

if(ret == -1){

2360

2015

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

2361

2016

exitcode = EX_UNAVAILABLE;

2368

2023

goto end;

2369

2024

}

2370

2025

2371

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

2372

tempdir = mkdtemp(run_tempdir);

2373

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

2374

if(debug){

2375

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

2376

run_tempdir, old_tempdir);

2377

}

2378

tempdir = mkdtemp(old_tempdir);

2379

}

2380

if(tempdir == NULL){

2026

if(mkdtemp(tempdir) == NULL){

2381

2027

perror_plus("mkdtemp");

2382

2028

goto end;

2383

2029

}

2030

tempdir_created = true;

2384

2031

2385

2032

if(quit_now){

2386

2033

goto end;

2387

2034

}

2388

2035

2389

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

2036

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

2390

2037

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

2391

2038

exitcode = EX_UNAVAILABLE;

2392

2039

goto end;

2402

2049

/* Connect directly, do not use Zeroconf */

2403

2050

/* (Mainly meant for debugging) */

2404

2051

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

2405

2406

2052

if(address == NULL){

2407

2053

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

2408

2054

exitcode = EX_USAGE;

2413

2059

goto end;

2414

2060

}

2415

2061

2416

in_port_t port;

2062

uint16_t port;

2417

2063

errno = 0;

2418

2064

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

2419

2065

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

2420

or tmpmax != (in_port_t)tmpmax){

2066

or tmpmax != (uint16_t)tmpmax){

2421

2067

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

2422

2068

exitcode = EX_USAGE;

2423

2069

goto end;

2424

2070

}

2425

2071

2426

2072

if(quit_now){

2427

2073

goto end;

2428

2074

}

2429

2075

2430

port = (in_port_t)tmpmax;

2076

port = (uint16_t)tmpmax;

2431

2077

*address = '\0';

2432

2078

/* Colon in address indicates IPv6 */

2433

2079

int af;

2449

2095

}

2450

2096

2451

2097

while(not quit_now){

2452

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

2453

&mc);

2098

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

2454

2099

if(quit_now or ret == 0){

2455

2100

break;

2456

2101

}

2458

2103

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

2459

2104

(int)retry_interval);

2460

2105

}

2461

sleep((unsigned int)retry_interval);

2106

sleep((int)retry_interval);

2462

2107

}

2463

2108

2464

if(not quit_now){

2109

if (not quit_now){

2465

2110

exitcode = EXIT_SUCCESS;

2466

2111

}

2467

2112

2482

2127

config.publish_domain = 0;

2483

2128

2484

2129

/* Allocate a new server */

2485

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2486

&config, NULL, NULL, &ret_errno);

2130

mc.server = avahi_server_new(avahi_simple_poll_get

2131

(mc.simple_poll), &config, NULL,

2132

NULL, &error);

2487

2133

2488

2134

/* Free the Avahi configuration data */

2489

2135

avahi_server_config_free(&config);

2492

2138

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

2493

2139

if(mc.server == NULL){

2494

2140

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

2495

avahi_strerror(ret_errno));

2141

avahi_strerror(error));

2496

2142

exitcode = EX_UNAVAILABLE;

2497

2143

goto end;

2498

2144

}

2504

2150

/* Create the Avahi service browser */

2505

2151

sb = avahi_s_service_browser_new(mc.server, if_index,

2506

2152

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2507

NULL, 0, browse_callback,

2508

(void *)&mc);

2153

NULL, 0, browse_callback, NULL);

2509

2154

if(sb == NULL){

2510

2155

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

2511

2156

avahi_strerror(avahi_server_errno(mc.server)));

2522

2167

if(debug){

2523

2168

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

2524

2169

}

2525

2526

ret = avahi_loop_with_timeout(simple_poll,

2527

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

2170

2171

ret = avahi_loop_with_timeout(mc.simple_poll,

2172

(int)(retry_interval * 1000));

2528

2173

if(debug){

2529

2174

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

2530

2175

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

2537

2182

}

2538

2183

2539

2184

/* Cleanup things */

2540

free(mc.interfaces);

2541

2542

2185

if(sb != NULL)

2543

2186

avahi_s_service_browser_free(sb);

2544

2187

2545

2188

if(mc.server != NULL)

2546

2189

avahi_server_free(mc.server);

2547

2190

2548

if(simple_poll != NULL)

2549

avahi_simple_poll_free(simple_poll);

2191

if(mc.simple_poll != NULL)

2192

avahi_simple_poll_free(mc.simple_poll);

2550

2193

2551

2194

if(gnutls_initialized){

2552

2195

gnutls_certificate_free_credentials(mc.cred);

2557

2200

if(gpgme_initialized){

2558

2201

gpgme_release(mc.ctx);

2559

2202

}

2560

2203

2561

2204

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

2562

2205

has seen */

2563

2206

if(mc.current_server != NULL){

2564

2207

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

2565

2208

while(mc.current_server != NULL){

2566

2209

server *next = mc.current_server->next;

2567

#ifdef __GNUC__

2568

#pragma GCC diagnostic push

2569

#pragma GCC diagnostic ignored "-Wcast-qual"

2570

#endif

2571

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

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic pop

2574

#endif

2575

2210

free(mc.current_server);

2576

2211

mc.current_server = next;

2577

2212

}

2578

2213

}

2579

2214

2580

/* Re-raise privileges */

2215

/* Re-raise priviliges */

2581

2216

{

2582

ret_errno = raise_privileges();

2583

if(ret_errno != 0){

2584

errno = ret_errno;

2585

perror_plus("Failed to raise privileges");

2586

} else {

2587

2588

/* Run network hooks */

2589

run_network_hooks("stop", interfaces_hooks != NULL ?

2590

interfaces_hooks : "", delay);

2591

2592

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

2593

{

2594

char *interface = NULL;

2595

while((interface=argz_next(interfaces_to_take_down,

2596

interfaces_to_take_down_size,

2597

interface))){

2598

ret_errno = take_down_interface(interface);

2599

if(ret_errno != 0){

2600

errno = ret_errno;

2601

perror_plus("Failed to take down interface");

2602

}

2603

}

2604

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

2605

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

2606

" down\n");

2607

}

2217

if(getuid() == 0){

2218

errno = 0;

2219

ret = seteuid(0);

2220

if(ret == -1){

2221

perror_plus("seteuid");

2608

2222

}

2609

2223

}

2224

/* Run network hooks */

2225

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

2226

goto end;

2227

}

2610

2228

2611

ret_errno = lower_privileges_permanently();

2612

if(ret_errno != 0){

2613

errno = ret_errno;

2614

perror_plus("Failed to lower privileges permanently");

2615

}

2616

}

2617

2618

free(interfaces_to_take_down);

2619

free(interfaces_hooks);

2229

/* Take down the network interface */

2230

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

2231

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

2232

if(ret == -1){

2233

perror_plus("ioctl SIOCGIFFLAGS");

2234

} else if(network.ifr_flags & IFF_UP){

2235

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

2236

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

2237

if(ret == -1){

2238

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2239

}

2240

}

2241

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

2242

if(ret == -1){

2243

perror_plus("close");

2244

}

2245

}

2246

}

2247

if(getuid() == 0){

2248

/* Lower privileges permanently */

2249

errno = 0;

2250

ret = setuid(uid);

2251

if(ret == -1){

2252

perror_plus("setuid");

2253

}

2254

}

2620

2255

2621

2256

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

2622

if(tempdir != NULL){

2257

if(tempdir_created){

2623

2258

struct dirent **direntries = NULL;

2624

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

2625

O_NOFOLLOW));

2626

if(tempdir_fd == -1){

2627

perror_plus("open");

2628

} else {

2629

#ifdef __GLIBC__

2630

#if __GLIBC_PREREQ(2, 15)

2631

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

2632

notdotentries, alphasort);

2633

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

2634

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

2635

alphasort);

2636

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

2637

#else /* not __GLIBC__ */

2638

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

2639

alphasort);

2640

#endif /* not __GLIBC__ */

2641

if(numentries >= 0){

2642

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

2643

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

2644

if(ret == -1){

2645

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

2646

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

2647

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

2648

}

2649

free(direntries[i]);

2650

}

2651

2652

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

2653

free(direntries);

2654

if(numentries == -1){

2655

perror_plus("scandir");

2656

}

2657

ret = rmdir(tempdir);

2658

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

2659

perror_plus("rmdir");

2660

}

2259

struct dirent *direntry = NULL;

2260

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

2261

alphasort);

2262

if (numentries > 0){

2263

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

2264

direntry = direntries[i];

2265

char *fullname = NULL;

2266

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

2267

direntry->d_name);

2268

if(ret < 0){

2269

perror_plus("asprintf");

2270

continue;

2271

}

2272

ret = remove(fullname);

2273

if(ret == -1){

2274

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

2275

strerror(errno));

2276

}

2277

free(fullname);

2661

2278

}

2662

TEMP_FAILURE_RETRY(close(tempdir_fd));

2279

}

2280

2281

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

2282

free(direntries);

2283

if (numentries == -1){

2284

perror_plus("scandir");

2285

}

2286

ret = rmdir(tempdir);

2287

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

2288

perror_plus("rmdir");

2663

2289

}

2664

2290

}

2665

2291