/mandos/release : revision 237.7.144

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

* This program is free software: you can redistribute it and/or

16

* modify it under the terms of the GNU General Public License as

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

41

42

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

43

stdout, ferror() */

43

stdout, ferror(), remove() */

44

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

45

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

46

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

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

58

inet_pton(), connect() */

59

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

61

60

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

62

61

*/

63

62

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

64

63

strtoimax() */

64

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

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

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program_invocation_short_name */

67

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

73

*/

74

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

75

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

76

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

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unlinkat() */

78

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

76

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

77

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

79

78

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

80

79

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

81

80

argp_state, struct argp,

93

92

argz_delete(), argz_append(),

94

93

argz_stringify(), argz_add(),

95

94

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

95

99

96

#ifdef __linux__

100

97

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

142

139

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

143

140

char *connect_to = NULL;

144

141

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

142

uid_t uid = 65534;

147

143

gid_t gid = 65534;

148

144

149

145

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

150

146

typedef struct server{

151

147

const char *ip;

152

in_port_t port;

148

uint16_t port;

153

149

AvahiIfIndex if_index;

154

150

int af;

155

151

struct timespec last_seen;

159

155

160

156

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

161

157

typedef struct {

158

AvahiSimplePoll *simple_poll;

162

159

AvahiServer *server;

163

160

gnutls_certificate_credentials_t cred;

164

161

unsigned int dh_bits;

166

163

const char *priority;

167

164

gpgme_ctx_t ctx;

168

165

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

166

} mandos_context;

172

167

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

168

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

169

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

170

.dh_bits = 1024, .priority = "SECURE256"

171

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

172

.current_server = NULL };

175

173

176

174

sig_atomic_t quit_now = 0;

177

175

int signal_received = 0;

185

183

perror(print_text);

186

184

}

187

185

188

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

186

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

189

187

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

190

188

va_list ap;

191

189

va_start (ap, format);

192

190

193

191

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

194

192

program_invocation_short_name));

195

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

193

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

196

194

}

197

195

198

196

/*

200

198

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

201

199

* "buffer_length" is how much is already used.

202

200

*/

203

__attribute__((nonnull, warn_unused_result))

204

201

size_t incbuffer(char **buffer, size_t buffer_length,

205

202

size_t buffer_capacity){

206

203

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;

204

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

205

if(buffer == NULL){

213

206

return 0;

214

207

}

215

*buffer = new_buf;

216

208

buffer_capacity += BUFFER_SIZE;

217

209

}

218

210

return buffer_capacity;

219

211

}

220

212

221

213

/* 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){

214

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

215

int af){

225

216

int ret;

226

217

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

227

218

if(new_server == NULL){

236

227

perror_plus("strdup");

237

228

return false;

238

229

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

230

/* Special case of first server */

245

if(*current_server == NULL){

231

if (mc.current_server == NULL){

246

232

new_server->next = new_server;

247

233

new_server->prev = new_server;

248

*current_server = new_server;

234

mc.current_server = new_server;

235

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

249

236

} else {

250

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

251

new_server->next = *current_server;

252

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

237

new_server->next = mc.current_server;

238

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

253

239

new_server->prev->next = new_server;

254

(*current_server)->prev = new_server;

240

mc.current_server->prev = new_server;

241

}

242

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

243

if(ret == -1){

244

perror_plus("clock_gettime");

245

return false;

255

246

}

256

247

return true;

257

248

}

259

250

/*

260

251

* Initialize GPGME.

261

252

*/

262

__attribute__((nonnull, warn_unused_result))

263

static bool init_gpgme(const char * const seckey,

264

const char * const pubkey,

265

const char * const tempdir,

266

mandos_context *mc){

253

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

254

const char *tempdir){

267

255

gpgme_error_t rc;

268

256

gpgme_engine_info_t engine_info;

269

257

258

270

259

/*

271

260

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

272

261

*/

273

bool import_key(const char * const filename){

262

bool import_key(const char *filename){

274

263

int ret;

275

264

int fd;

276

265

gpgme_data_t pgp_data;

288

277

return false;

289

278

}

290

279

291

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

280

rc = gpgme_op_import(mc.ctx, pgp_data);

292

281

if(rc != GPG_ERR_NO_ERROR){

293

282

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

294

283

gpgme_strsource(rc), gpgme_strerror(rc));

338

327

}

339

328

340

329

/* Create new GPGME "context" */

341

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

330

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

342

331

if(rc != GPG_ERR_NO_ERROR){

343

332

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

344

333

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

357

346

* Decrypt OpenPGP data.

358

347

* Returns -1 on error

359

348

*/

360

__attribute__((nonnull, warn_unused_result))

361

349

static ssize_t pgp_packet_decrypt(const char *cryptotext,

362

350

size_t crypto_size,

363

char **plaintext,

364

mandos_context *mc){

351

char **plaintext){

365

352

gpgme_data_t dh_crypto, dh_plain;

366

353

gpgme_error_t rc;

367

354

ssize_t ret;

393

380

394

381

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

395

382

data buffer */

396

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

383

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

397

384

if(rc != GPG_ERR_NO_ERROR){

398

385

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

399

386

gpgme_strsource(rc), gpgme_strerror(rc));

400

387

plaintext_length = -1;

401

388

if(debug){

402

389

gpgme_decrypt_result_t result;

403

result = gpgme_op_decrypt_result(mc->ctx);

390

result = gpgme_op_decrypt_result(mc.ctx);

404

391

if(result == NULL){

405

392

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

406

393

} else {

483

470

return plaintext_length;

484

471

}

485

472

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

488

const char *ret = gnutls_strerror(value);

473

static const char * safer_gnutls_strerror(int value){

474

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

475

-Wunreachable-code */

489

476

if(ret == NULL)

490

477

ret = "(unknown)";

491

478

return ret;

492

479

}

493

480

494

481

/* GnuTLS log function callback */

495

__attribute__((nonnull))

496

482

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

497

483

const char* string){

498

484

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

499

485

}

500

486

501

__attribute__((nonnull, warn_unused_result))

502

487

static int init_gnutls_global(const char *pubkeyfilename,

503

const char *seckeyfilename,

504

mandos_context *mc){

488

const char *seckeyfilename){

505

489

int ret;

506

490

507

491

if(debug){

524

508

}

525

509

526

510

/* OpenPGP credentials */

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

511

ret = gnutls_certificate_allocate_credentials(&mc.cred);

528

512

if(ret != GNUTLS_E_SUCCESS){

529

513

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

530

514

safer_gnutls_strerror(ret));

540

524

}

541

525

542

526

ret = gnutls_certificate_set_openpgp_key_file

543

(mc->cred, pubkeyfilename, seckeyfilename,

527

(mc.cred, pubkeyfilename, seckeyfilename,

544

528

GNUTLS_OPENPGP_FMT_BASE64);

545

529

if(ret != GNUTLS_E_SUCCESS){

546

530

fprintf_plus(stderr,

552

536

}

553

537

554

538

/* GnuTLS server initialization */

555

ret = gnutls_dh_params_init(&mc->dh_params);

539

ret = gnutls_dh_params_init(&mc.dh_params);

556

540

if(ret != GNUTLS_E_SUCCESS){

557

541

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

558

542

" initialization: %s\n",

559

543

safer_gnutls_strerror(ret));

560

544

goto globalfail;

561

545

}

562

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

546

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

563

547

if(ret != GNUTLS_E_SUCCESS){

564

548

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

565

549

safer_gnutls_strerror(ret));

566

550

goto globalfail;

567

551

}

568

552

569

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

553

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

570

554

571

555

return 0;

572

556

573

557

globalfail:

574

558

575

gnutls_certificate_free_credentials(mc->cred);

559

gnutls_certificate_free_credentials(mc.cred);

576

560

gnutls_global_deinit();

577

gnutls_dh_params_deinit(mc->dh_params);

561

gnutls_dh_params_deinit(mc.dh_params);

578

562

return -1;

579

563

}

580

564

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

565

static int init_gnutls_session(gnutls_session_t *session){

584

566

int ret;

585

567

/* GnuTLS session creation */

586

568

do {

598

580

{

599

581

const char *err;

600

582

do {

601

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

583

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

602

584

if(quit_now){

603

585

gnutls_deinit(*session);

604

586

return -1;

615

597

616

598

do {

617

599

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

618

mc->cred);

600

mc.cred);

619

601

if(quit_now){

620

602

gnutls_deinit(*session);

621

603

return -1;

631

613

/* ignore client certificate if any. */

632

614

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

633

615

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

616

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

635

617

636

618

return 0;

637

619

}

641

623

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

642

624

643

625

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

645

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

626

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

646

627

AvahiIfIndex if_index,

647

int af, mandos_context *mc){

628

int af){

648

629

int ret, tcp_sd = -1;

649

630

ssize_t sret;

650

struct sockaddr_storage to;

631

union {

632

struct sockaddr_in in;

633

struct sockaddr_in6 in6;

634

} to;

651

635

char *buffer = NULL;

652

636

char *decrypted_buffer = NULL;

653

637

size_t buffer_length = 0;

677

661

return -1;

678

662

}

679

663

680

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

681

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

682

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

683

bool match = false;

684

{

685

char *interface = NULL;

686

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

687

interface))){

688

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

689

match = true;

690

break;

691

}

692

}

693

}

694

if(not match){

695

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

696

connect to the server */

697

if(debug){

698

char interface[IF_NAMESIZE];

699

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

700

perror_plus("if_indextoname");

701

} else {

702

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

703

" \"%s\"\n",

704

if_indextoname((unsigned int)if_index,

705

interface));

706

}

707

}

708

return -1;

709

}

710

}

711

712

ret = init_gnutls_session(&session, mc);

664

ret = init_gnutls_session(&session);

713

665

if(ret != 0){

714

666

return -1;

715

667

}

716

668

717

669

if(debug){

718

670

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

719

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

671

PRIu16 "\n", ip, port);

720

672

}

721

673

722

674

tcp_sd = socket(pf, SOCK_STREAM, 0);

734

686

735

687

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

736

688

if(af == AF_INET6){

737

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

738

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

689

to.in6.sin6_family = (sa_family_t)af;

690

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

739

691

} else { /* IPv4 */

740

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

741

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

692

to.in.sin_family = (sa_family_t)af;

693

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

742

694

}

743

695

if(ret < 0 ){

744

696

int e = errno;

753

705

goto mandos_end;

754

706

}

755

707

if(af == AF_INET6){

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

708

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

709

-Wconversion and

710

-Wunreachable-code */

711

712

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

713

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

714

-Wunreachable-code*/

759

715

if(if_index == AVAHI_IF_UNSPEC){

760

716

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

761

717

" incomplete without a network interface\n");

763

719

goto mandos_end;

764

720

}

765

721

/* Set the network interface number as scope */

766

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

722

to.in6.sin6_scope_id = (uint32_t)if_index;

767

723

}

768

724

} else {

769

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

725

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

726

-Wconversion and

727

-Wunreachable-code */

770

728

}

771

729

772

730

if(quit_now){

780

738

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

781

739

perror_plus("if_indextoname");

782

740

} else {

783

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

784

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

741

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

742

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

785

743

}

786

744

} else {

787

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

788

ip, (uintmax_t)port);

745

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

746

ip, port);

789

747

}

790

748

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

791

749

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

750

const char *pcret;

792

751

if(af == AF_INET6){

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

752

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

753

sizeof(addrstr));

797

754

} else {

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

755

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

756

sizeof(addrstr));

802

757

}

803

if(ret == EAI_SYSTEM){

804

perror_plus("getnameinfo");

805

} else if(ret != 0) {

806

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

807

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

808

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

758

if(pcret == NULL){

759

perror_plus("inet_ntop");

760

} else {

761

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

762

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

763

}

809

764

}

810

765

}

811

766

815

770

}

816

771

817

772

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

773

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

820

774

} else {

821

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

822

sizeof(struct sockaddr_in));

775

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

823

776

}

824

777

if(ret < 0){

825

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

778

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

826

779

int e = errno;

827

780

perror_plus("connect");

828

781

errno = e;

989

942

if(buffer_length > 0){

990

943

ssize_t decrypted_buffer_size;

991

944

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

992

&decrypted_buffer, mc);

945

&decrypted_buffer);

993

946

if(decrypted_buffer_size >= 0){

994

947

995

948

written = 0;

1043

996

return retval;

1044

997

}

1045

998

1046

__attribute__((nonnull))

1047

999

static void resolve_callback(AvahiSServiceResolver *r,

1048

1000

AvahiIfIndex interface,

1049

1001

AvahiProtocol proto,

1057

1009

AVAHI_GCC_UNUSED AvahiStringList *txt,

1058

1010

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1059

1011

flags,

1060

void *mc){

1061

if(r == NULL){

1062

return;

1063

}

1012

AVAHI_GCC_UNUSED void* userdata){

1013

assert(r);

1064

1014

1065

1015

/* Called whenever a service has been resolved successfully or

1066

1016

timed out */

1075

1025

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

1076

1026

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

1077

1027

domain,

1078

avahi_strerror(avahi_server_errno

1079

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

1028

avahi_strerror(avahi_server_errno(mc.server)));

1080

1029

break;

1081

1030

1082

1031

case AVAHI_RESOLVER_FOUND:

1088

1037

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

1089

1038

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

1090

1039

}

1091

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

1092

interface,

1093

avahi_proto_to_af(proto),

1094

mc);

1040

int ret = start_mandos_communication(ip, port, interface,

1041

avahi_proto_to_af(proto));

1095

1042

if(ret == 0){

1096

avahi_simple_poll_quit(simple_poll);

1043

avahi_simple_poll_quit(mc.simple_poll);

1097

1044

} else {

1098

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

1099

avahi_proto_to_af(proto),

1100

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

1045

if(not add_server(ip, port, interface,

1046

avahi_proto_to_af(proto))){

1101

1047

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

1102

1048

" list\n", name);

1103

1049

}

1116

1062

const char *domain,

1117

1063

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1118

1064

flags,

1119

void *mc){

1120

if(b == NULL){

1121

return;

1122

}

1065

AVAHI_GCC_UNUSED void* userdata){

1066

assert(b);

1123

1067

1124

1068

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

1125

1069

is removed from the LAN */

1133

1077

case AVAHI_BROWSER_FAILURE:

1134

1078

1135

1079

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

1136

avahi_strerror(avahi_server_errno

1137

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

1138

avahi_simple_poll_quit(simple_poll);

1080

avahi_strerror(avahi_server_errno(mc.server)));

1081

avahi_simple_poll_quit(mc.simple_poll);

1139

1082

return;

1140

1083

1141

1084

case AVAHI_BROWSER_NEW:

1144

1087

the callback function is called the Avahi server will free the

1145

1088

resolver for us. */

1146

1089

1147

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

1148

interface, protocol, name, type,

1149

domain, protocol, 0,

1150

resolve_callback, mc) == NULL)

1090

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

1091

name, type, domain, protocol, 0,

1092

resolve_callback, NULL) == NULL)

1151

1093

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

1152

1094

" %s\n", name,

1153

avahi_strerror(avahi_server_errno

1154

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

1095

avahi_strerror(avahi_server_errno(mc.server)));

1155

1096

break;

1156

1097

1157

1098

case AVAHI_BROWSER_REMOVE:

1176

1117

signal_received = sig;

1177

1118

int old_errno = errno;

1178

1119

/* set main loop to exit */

1179

if(simple_poll != NULL){

1180

avahi_simple_poll_quit(simple_poll);

1120

if(mc.simple_poll != NULL){

1121

avahi_simple_poll_quit(mc.simple_poll);

1181

1122

}

1182

1123

errno = old_errno;

1183

1124

}

1184

1125

1185

__attribute__((nonnull, warn_unused_result))

1186

1126

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

1187

1127

int ret;

1188

1128

error_t ret_errno;

1207

1147

return true;

1208

1148

}

1209

1149

1210

__attribute__((nonnull, warn_unused_result))

1211

1150

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

1212

1151

1213

1152

/* Reject the loopback device */

1255

1194

* corresponds to an acceptable network device.

1256

1195

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

1257

1196

*/

1258

__attribute__((nonnull, warn_unused_result))

1259

1197

int good_interface(const struct dirent *if_entry){

1260

1198

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

1261

1199

return 0;

1279

1217

/*

1280

1218

* This function determines if a network interface is up.

1281

1219

*/

1282

__attribute__((nonnull, warn_unused_result))

1283

1220

bool interface_is_up(const char *interface){

1284

1221

struct ifreq ifr;

1285

1222

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

1296

1233

/*

1297

1234

* This function determines if a network interface is running

1298

1235

*/

1299

__attribute__((nonnull, warn_unused_result))

1300

1236

bool interface_is_running(const char *interface){

1301

1237

struct ifreq ifr;

1302

1238

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

1310

1246

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

1311

1247

}

1312

1248

1313

__attribute__((nonnull, pure, warn_unused_result))

1314

1249

int notdotentries(const struct dirent *direntry){

1315

1250

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

1316

1251

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

1323

1258

}

1324

1259

1325

1260

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

1326

__attribute__((nonnull, warn_unused_result))

1327

1261

int runnable_hook(const struct dirent *direntry){

1328

1262

int ret;

1329

1263

size_t sret;

1337

1271

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

1338

1272

"abcdefghijklmnopqrstuvwxyz"

1339

1273

"0123456789"

1340

"_.-");

1274

"_-");

1341

1275

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

1342

1276

/* Contains non-allowed characters */

1343

1277

if(debug){

1347

1281

return 0;

1348

1282

}

1349

1283

1350

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

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1351

1292

if(ret == -1){

1352

1293

if(debug){

1353

1294

perror_plus("Could not stat hook");

1377

1318

return 1;

1378

1319

}

1379

1320

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1383

1322

int ret;

1384

1323

struct timespec now;

1385

1324

struct timespec waited_time;

1386

1325

intmax_t block_time;

1387

1326

1388

1327

while(true){

1389

if(mc->current_server == NULL){

1390

if(debug){

1328

if(mc.current_server == NULL){

1329

if (debug){

1391

1330

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

1392

1331

" No timeout!\n");

1393

1332

}

1394

1333

ret = avahi_simple_poll_iterate(s, -1);

1395

1334

} else {

1396

if(debug){

1335

if (debug){

1397

1336

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

1398

1337

" it, or wait\n");

1399

1338

}

1406

1345

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

1407

1346

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

1408

1347

waited_time.tv_sec = (now.tv_sec

1409

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

1348

- mc.current_server->last_seen.tv_sec);

1410

1349

waited_time.tv_nsec = (now.tv_nsec

1411

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

1350

- mc.current_server->last_seen.tv_nsec);

1412

1351

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

1413

1352

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

1414

1353

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

1416

1355

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

1417

1356

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

1418

1357

1419

if(debug){

1358

if (debug){

1420

1359

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

1421

1360

block_time);

1422

1361

}

1423

1362

1424

1363

if(block_time <= 0){

1425

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

1426

mc->current_server->port,

1427

mc->current_server->if_index,

1428

mc->current_server->af, mc);

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1429

1368

if(ret == 0){

1430

avahi_simple_poll_quit(s);

1369

avahi_simple_poll_quit(mc.simple_poll);

1431

1370

return 0;

1432

1371

}

1433

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1434

&mc->current_server->last_seen);

1373

&mc.current_server->last_seen);

1435

1374

if(ret == -1){

1436

1375

perror_plus("clock_gettime");

1437

1376

return -1;

1438

1377

}

1439

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

1378

mc.current_server = mc.current_server->next;

1440

1379

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

1441

1380

servers, but don't block */

1442

1381

}

1444

1383

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

1445

1384

}

1446

1385

if(ret != 0){

1447

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

1386

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

1448

1387

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

1449

1388

}

1450

1389

}

1452

1391

}

1453

1392

1454

1393

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

1455

__attribute__((warn_unused_result))

1456

1394

error_t raise_privileges(void){

1457

1395

error_t old_errno = errno;

1458

1396

error_t ret_errno = 0;

1459

1397

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

1460

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1461

1400

}

1462

1401

errno = old_errno;

1463

1402

return ret_errno;

1464

1403

}

1465

1404

1466

1405

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

1467

__attribute__((warn_unused_result))

1468

1406

error_t raise_privileges_permanently(void){

1469

1407

error_t old_errno = errno;

1470

1408

error_t ret_errno = raise_privileges();

1474

1412

}

1475

1413

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

1476

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1477

1416

}

1478

1417

errno = old_errno;

1479

1418

return ret_errno;

1480

1419

}

1481

1420

1482

1421

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

1483

__attribute__((warn_unused_result))

1484

1422

error_t lower_privileges(void){

1485

1423

error_t old_errno = errno;

1486

1424

error_t ret_errno = 0;

1487

1425

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

1488

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1489

1428

}

1490

1429

errno = old_errno;

1491

1430

return ret_errno;

1492

1431

}

1493

1432

1494

1433

/* Lower privileges permanently */

1495

__attribute__((warn_unused_result))

1496

1434

error_t lower_privileges_permanently(void){

1497

1435

error_t old_errno = errno;

1498

1436

error_t ret_errno = 0;

1499

1437

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

1500

1438

ret_errno = errno;

1439

perror_plus("setuid");

1501

1440

}

1502

1441

errno = old_errno;

1503

1442

return ret_errno;

1504

1443

}

1505

1444

1506

__attribute__((nonnull))

1507

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

1445

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

1508

1446

const float delay){

1509

struct dirent **direntries = NULL;

1510

if(hookdir_fd == -1){

1511

hookdir_fd = open(hookdir, O_RDONLY);

1512

if(hookdir_fd == -1){

1513

if(errno == ENOENT){

1514

if(debug){

1515

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

1516

" found\n", hookdir);

1517

}

1518

} else {

1519

perror_plus("open");

1520

}

1521

return;

1522

}

1523

}

1524

#ifdef __GLIBC__

1525

#if __GLIBC_PREREQ(2, 15)

1526

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

1527

runnable_hook, alphasort);

1528

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

1529

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

1530

alphasort);

1531

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

1532

#else /* not __GLIBC__ */

1533

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

1534

alphasort);

1535

#endif /* not __GLIBC__ */

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1536

1452

if(numhooks == -1){

1537

1453

perror_plus("scandir");

1538

return;

1539

}

1540

struct dirent *direntry;

1541

int ret;

1542

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

1543

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

1544

direntry = direntries[i];

1545

if(debug){

1546

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

1547

direntry->d_name);

1548

}

1549

pid_t hook_pid = fork();

1550

if(hook_pid == 0){

1551

/* Child */

1552

/* Raise privileges */

1553

errno = raise_privileges_permanently();

1554

if(errno != 0){

1555

perror_plus("Failed to raise privileges");

1556

_exit(EX_NOPERM);

1557

}

1558

/* Set group */

1559

errno = 0;

1560

ret = setgid(0);

1561

if(ret == -1){

1562

perror_plus("setgid");

1563

_exit(EX_NOPERM);

1564

}

1565

/* Reset supplementary groups */

1566

errno = 0;

1567

ret = setgroups(0, NULL);

1568

if(ret == -1){

1569

perror_plus("setgroups");

1570

_exit(EX_NOPERM);

1571

}

1572

ret = dup2(devnull, STDIN_FILENO);

1573

if(ret == -1){

1574

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

1575

_exit(EX_OSERR);

1576

}

1577

ret = close(devnull);

1578

if(ret == -1){

1579

perror_plus("close");

1580

_exit(EX_OSERR);

1581

}

1582

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1583

if(ret == -1){

1584

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

1585

_exit(EX_OSERR);

1586

}

1587

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

1588

if(ret == -1){

1589

perror_plus("setenv");

1590

_exit(EX_OSERR);

1591

}

1592

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

1593

if(ret == -1){

1594

perror_plus("setenv");

1595

_exit(EX_OSERR);

1596

}

1597

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

1598

if(ret == -1){

1599

perror_plus("setenv");

1600

_exit(EX_OSERR);

1601

}

1602

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

1603

if(ret == -1){

1604

perror_plus("setenv");

1605

_exit(EX_OSERR);

1606

}

1607

char *delaystring;

1608

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

1609

if(ret == -1){

1454

} else {

1455

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

1456

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

1457

direntry = direntries[i];

1458

char *fullname = NULL;

1459

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

1460

if(ret < 0){

1610

1461

perror_plus("asprintf");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1462

continue;

1463

}

1464

if(debug){

1465

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

1466

direntry->d_name);

1467

}

1468

pid_t hook_pid = fork();

1469

if(hook_pid == 0){

1470

/* Child */

1471

/* Raise privileges */

1472

raise_privileges_permanently();

1473

/* Set group */

1474

errno = 0;

1475

ret = setgid(0);

1476

if(ret == -1){

1477

perror_plus("setgid");

1478

}

1479

/* Reset supplementary groups */

1480

errno = 0;

1481

ret = setgroups(0, NULL);

1482

if(ret == -1){

1483

perror_plus("setgroups");

1484

}

1485

dup2(devnull, STDIN_FILENO);

1486

close(devnull);

1487

dup2(STDERR_FILENO, STDOUT_FILENO);

1488

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

1489

if(ret == -1){

1490

perror_plus("setenv");

1491

_exit(EX_OSERR);

1492

}

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

char *delaystring;

1509

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

1510

if(ret == -1){

1511

perror_plus("asprintf");

1512

_exit(EX_OSERR);

1513

}

1514

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

1515

if(ret == -1){

1516

free(delaystring);

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1615

1520

free(delaystring);

1616

perror_plus("setenv");

1617

_exit(EX_OSERR);

1618

}

1619

free(delaystring);

1620

if(connect_to != NULL){

1621

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

1622

if(ret == -1){

1623

perror_plus("setenv");

1624

_exit(EX_OSERR);

1625

}

1626

}

1627

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

1628

if(hook_fd == -1){

1629

perror_plus("openat");

1630

_exit(EXIT_FAILURE);

1631

}

1632

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

1633

perror_plus("close");

1634

_exit(EXIT_FAILURE);

1635

}

1636

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

1637

environ) == -1){

1638

perror_plus("fexecve");

1639

_exit(EXIT_FAILURE);

1640

}

1641

} else {

1642

int status;

1643

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

1644

perror_plus("waitpid");

1645

continue;

1646

}

1647

if(WIFEXITED(status)){

1648

if(WEXITSTATUS(status) != 0){

1649

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

1650

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

1651

WEXITSTATUS(status));

1652

continue;

1653

}

1654

} else if(WIFSIGNALED(status)){

1655

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

1656

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

1657

WTERMSIG(status));

1658

continue;

1521

if(connect_to != NULL){

1522

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

1523

if(ret == -1){

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1527

}

1528

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

1529

perror_plus("execl");

1530

_exit(EXIT_FAILURE);

1531

}

1659

1532

} else {

1660

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

1661

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

1662

continue;

1663

}

1664

}

1665

if(debug){

1666

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

1667

direntry->d_name);

1668

}

1669

}

1670

free(direntries);

1671

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

1672

perror_plus("close");

1673

} else {

1674

hookdir_fd = -1;

1675

}

1676

close(devnull);

1533

int status;

1534

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

1535

perror_plus("waitpid");

1536

free(fullname);

1537

continue;

1538

}

1539

if(WIFEXITED(status)){

1540

if(WEXITSTATUS(status) != 0){

1541

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

1542

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

1543

WEXITSTATUS(status));

1544

free(fullname);

1545

continue;

1546

}

1547

} else if(WIFSIGNALED(status)){

1548

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

1549

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

1550

WTERMSIG(status));

1551

free(fullname);

1552

continue;

1553

} else {

1554

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

1555

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

1556

free(fullname);

1557

continue;

1558

}

1559

}

1560

free(fullname);

1561

if(debug){

1562

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

1563

direntry->d_name);

1564

}

1565

}

1566

close(devnull);

1567

}

1568

return true;

1677

1569

}

1678

1570

1679

__attribute__((nonnull, warn_unused_result))

1680

1571

error_t bring_up_interface(const char *const interface,

1681

1572

const float delay){

1573

int sd = -1;

1682

1574

error_t old_errno = errno;

1683

int ret;

1575

error_t ret_errno = 0;

1576

int ret, ret_setflags;

1684

1577

struct ifreq network;

1685

1578

unsigned int if_index = if_nametoindex(interface);

1686

1579

if(if_index == 0){

1695

1588

}

1696

1589

1697

1590

if(not interface_is_up(interface)){

1698

error_t ret_errno = 0, ioctl_errno = 0;

1699

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

1591

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

1700

1592

ret_errno = errno;

1701

1593

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

1702

1594

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

1703

errno = old_errno;

1704

1595

return ret_errno;

1705

1596

}

1706

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

1597

network.ifr_flags |= IFF_UP;

1707

1598

1708

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

1709

if(sd == -1){

1599

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1600

if(sd < 0){

1710

1601

ret_errno = errno;

1711

1602

perror_plus("socket");

1712

1603

errno = old_errno;

1713

1604

return ret_errno;

1714

1605

}

1715

1606

1716

1607

if(quit_now){

1717

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

1718

if(ret == -1){

1719

perror_plus("close");

1720

}

1608

close(sd);

1721

1609

errno = old_errno;

1722

1610

return EINTR;

1723

1611

}

1727

1615

interface);

1728

1616

}

1729

1617

1730

/* Raise privileges */

1731

ret_errno = raise_privileges();

1732

if(ret_errno != 0){

1733

errno = ret_errno;

1734

perror_plus("Failed to raise privileges");

1735

}

1618

/* Raise priviliges */

1619

raise_privileges();

1736

1620

1737

1621

#ifdef __linux__

1738

int ret_linux;

1739

bool restore_loglevel = false;

1740

if(ret_errno == 0){

1741

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1742

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

1743

ret_linux = klogctl(8, NULL, 5);

1744

if(ret_linux == -1){

1745

perror_plus("klogctl");

1746

} else {

1747

restore_loglevel = true;

1748

}

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

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

1625

bool restore_loglevel = true;

1626

if(ret_linux == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1749

1629

}

1750

1630

#endif /* __linux__ */

1751

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

1752

ioctl_errno = errno;

1631

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

1632

ret_errno = errno;

1753

1633

#ifdef __linux__

1754

1634

if(restore_loglevel){

1755

1635

ret_linux = klogctl(7, NULL, 0);

1759

1639

}

1760

1640

#endif /* __linux__ */

1761

1641

1762

/* If raise_privileges() succeeded above */

1763

if(ret_errno == 0){

1764

/* Lower privileges */

1765

ret_errno = lower_privileges();

1766

if(ret_errno != 0){

1767

errno = ret_errno;

1768

perror_plus("Failed to lower privileges");

1769

}

1770

}

1642

/* Lower privileges */

1643

lower_privileges();

1771

1644

1772

1645

/* Close the socket */

1773

1646

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

1776

1649

}

1777

1650

1778

1651

if(ret_setflags == -1){

1779

errno = ioctl_errno;

1652

errno = ret_errno;

1780

1653

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1781

1654

errno = old_errno;

1782

return ioctl_errno;

1655

return ret_errno;

1783

1656

}

1784

1657

} else if(debug){

1785

1658

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

1803

1676

return 0;

1804

1677

}

1805

1678

1806

__attribute__((nonnull, warn_unused_result))

1807

1679

error_t take_down_interface(const char *const interface){

1680

int sd = -1;

1808

1681

error_t old_errno = errno;

1682

error_t ret_errno = 0;

1683

int ret, ret_setflags;

1809

1684

struct ifreq network;

1810

1685

unsigned int if_index = if_nametoindex(interface);

1811

1686

if(if_index == 0){

1814

1689

return ENXIO;

1815

1690

}

1816

1691

if(interface_is_up(interface)){

1817

error_t ret_errno = 0, ioctl_errno = 0;

1818

1692

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

1819

1693

ret_errno = errno;

1820

1694

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

1821

1695

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

1822

errno = old_errno;

1823

1696

return ret_errno;

1824

1697

}

1825

1698

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

1826

1699

1827

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

1828

if(sd == -1){

1700

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1701

if(sd < 0){

1829

1702

ret_errno = errno;

1830

1703

perror_plus("socket");

1831

1704

errno = old_errno;

1837

1710

interface);

1838

1711

}

1839

1712

1840

/* Raise privileges */

1841

ret_errno = raise_privileges();

1842

if(ret_errno != 0){

1843

errno = ret_errno;

1844

perror_plus("Failed to raise privileges");

1845

}

1846

1847

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

1848

ioctl_errno = errno;

1849

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

1713

/* Raise priviliges */

1714

raise_privileges();

1715

1716

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

1717

ret_errno = errno;

1718

1719

/* Lower privileges */

1720

lower_privileges();

1859

1721

1860

1722

/* Close the socket */

1861

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

1723

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

1862

1724

if(ret == -1){

1863

1725

perror_plus("close");

1864

1726

}

1865

1727

1866

1728

if(ret_setflags == -1){

1867

errno = ioctl_errno;

1729

errno = ret_errno;

1868

1730

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1869

1731

errno = old_errno;

1870

return ioctl_errno;

1732

return ret_errno;

1871

1733

}

1872

1734

} else if(debug){

1873

1735

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

1879

1741

}

1880

1742

1881

1743

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

1882

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

1883

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

1884

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

1885

.interfaces = NULL, .interfaces_size = 0 };

1886

1744

AvahiSServiceBrowser *sb = NULL;

1887

1745

error_t ret_errno;

1888

1746

int ret;

1889

1747

intmax_t tmpmax;

1890

1748

char *tmp;

1891

1749

int exitcode = EXIT_SUCCESS;

1750

char *interfaces = NULL;

1751

size_t interfaces_size = 0;

1892

1752

char *interfaces_to_take_down = NULL;

1893

1753

size_t interfaces_to_take_down_size = 0;

1894

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

1895

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

1896

char *tempdir = NULL;

1754

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

1755

bool tempdir_created = false;

1897

1756

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1898

1757

const char *seckey = PATHDIR "/" SECKEY;

1899

1758

const char *pubkey = PATHDIR "/" PUBKEY;

1900

1759

char *interfaces_hooks = NULL;

1760

size_t interfaces_hooks_size = 0;

1901

1761

1902

1762

bool gnutls_initialized = false;

1903

1763

bool gpgme_initialized = false;

1994

1854

connect_to = arg;

1995

1855

break;

1996

1856

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

1997

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

1998

arg, (int)',');

1857

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

1858

(int)',');

1999

1859

if(ret_errno != 0){

2000

1860

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

2001

1861

}

2081

1941

/* Work around Debian bug #633582:

2082

1942

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

2083

1943

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

2089

} else {

1944

/* Re-raise priviliges */

1945

if(raise_privileges() == 0){

2090

1946

struct stat st;

2091

1947

2092

1948

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

2132

1988

}

2133

1989

2134

1990

/* Lower privileges */

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

1991

errno = 0;

1992

ret = seteuid(uid);

1993

if(ret == -1){

1994

perror_plus("seteuid");

2139

1995

}

2140

1996

}

2141

1997

}

2142

1998

2143

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

1999

/* Remove empty interface names */

2144

2000

{

2145

2001

char *interface = NULL;

2146

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

2002

while((interface = argz_next(interfaces, interfaces_size,

2147

2003

interface))){

2148

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

2149

and if_nametoindex(interface) == 0){

2150

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

2004

if(if_nametoindex(interface) == 0){

2005

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

2151

2006

fprintf_plus(stderr, "Not using nonexisting interface"

2152

2007

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

2153

2008

}

2154

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

2009

argz_delete(&interfaces, &interfaces_size, interface);

2155

2010

interface = NULL;

2156

2011

}

2157

2012

}

2159

2014

2160

2015

/* Run network hooks */

2161

2016

{

2162

if(mc.interfaces != NULL){

2163

interfaces_hooks = malloc(mc.interfaces_size);

2164

if(interfaces_hooks == NULL){

2165

perror_plus("malloc");

2166

goto end;

2167

}

2168

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

2169

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

2170

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

2017

ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,

2018

interfaces, interfaces_size);

2019

if(ret_errno != 0){

2020

errno = ret_errno;

2021

perror_plus("argz_append");

2022

goto end;

2023

}

2024

argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');

2025

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

2026

goto end;

2027

}

2173

2028

}

2174

2029

2175

2030

if(not debug){

2180

2035

from the signal handler */

2181

2036

/* Initialize the pseudo-RNG for Avahi */

2182

2037

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

2183

simple_poll = avahi_simple_poll_new();

2184

if(simple_poll == NULL){

2038

mc.simple_poll = avahi_simple_poll_new();

2039

if(mc.simple_poll == NULL){

2185

2040

fprintf_plus(stderr,

2186

2041

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

2187

2042

exitcode = EX_UNAVAILABLE;

2252

2107

}

2253

2108

2254

2109

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

2255

if(mc.interfaces == NULL){

2256

struct dirent **direntries = NULL;

2110

if(interfaces == NULL){

2111

struct dirent **direntries;

2257

2112

/* Look for any good interfaces */

2258

2113

ret = scandir(sys_class_net, &direntries, good_interface,

2259

2114

alphasort);

2260

2115

if(ret >= 1){

2261

2116

/* Add all found interfaces to interfaces list */

2262

2117

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

2263

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

2118

ret_errno = argz_add(&interfaces, &interfaces_size,

2264

2119

direntries[i]->d_name);

2265

2120

if(ret_errno != 0){

2266

errno = ret_errno;

2267

2121

perror_plus("argz_add");

2268

2122

continue;

2269

2123

}

2274

2128

}

2275

2129

free(direntries);

2276

2130

} else {

2277

if(ret == 0){

2278

free(direntries);

2279

}

2131

free(direntries);

2280

2132

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

2281

2133

exitcode = EXIT_FAILURE;

2282

2134

goto end;

2283

2135

}

2284

2136

}

2285

2137

2286

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

2287

{

2138

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

2139

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

2140

if(debug){

2141

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

2142

interfaces);

2143

}

2144

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2145

}

2146

2147

/* Bring up interfaces which are down */

2148

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

2149

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

2288

2150

char *interface = NULL;

2289

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

2151

while((interface = argz_next(interfaces, interfaces_size,

2290

2152

interface))){

2291

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

2292

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

2293

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

2294

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

2295

interface);

2296

interface = NULL;

2297

while((interface = argz_next(mc.interfaces,

2298

mc.interfaces_size, interface))){

2299

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

2300

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

2301

interface);

2302

interface = NULL;

2303

}

2304

}

2305

break;

2306

}

2307

2153

bool interface_was_up = interface_is_up(interface);

2308

errno = bring_up_interface(interface, delay);

2154

ret = bring_up_interface(interface, delay);

2309

2155

if(not interface_was_up){

2310

if(errno != 0){

2156

if(ret != 0){

2157

errno = ret;

2311

2158

perror_plus("Failed to bring up interface");

2312

2159

} else {

2313

errno = argz_add(&interfaces_to_take_down,

2314

&interfaces_to_take_down_size,

2315

interface);

2316

if(errno != 0){

2317

perror_plus("argz_add");

2318

}

2160

ret_errno = argz_add(&interfaces_to_take_down,

2161

&interfaces_to_take_down_size,

2162

interface);

2319

2163

}

2320

2164

}

2321

2165

}

2166

free(interfaces);

2167

interfaces = NULL;

2168

interfaces_size = 0;

2322

2169

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

2323

2170

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

2324

2171

}

2325

2172

}

2326

2173

2327

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

2328

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

2329

if(debug){

2330

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

2331

mc.interfaces);

2332

}

2333

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

2334

}

2335

2336

2174

if(quit_now){

2337

2175

goto end;

2338

2176

}

2339

2177

2340

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

2178

ret = init_gnutls_global(pubkey, seckey);

2341

2179

if(ret == -1){

2342

2180

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

2343

2181

exitcode = EX_UNAVAILABLE;

2350

2188

goto end;

2351

2189

}

2352

2190

2353

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

2354

tempdir = mkdtemp(run_tempdir);

2355

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

2356

if(debug){

2357

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

2358

run_tempdir, old_tempdir);

2359

}

2360

tempdir = mkdtemp(old_tempdir);

2361

}

2362

if(tempdir == NULL){

2191

if(mkdtemp(tempdir) == NULL){

2363

2192

perror_plus("mkdtemp");

2364

2193

goto end;

2365

2194

}

2195

tempdir_created = true;

2366

2196

2367

2197

if(quit_now){

2368

2198

goto end;

2369

2199

}

2370

2200

2371

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

2201

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

2372

2202

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

2373

2203

exitcode = EX_UNAVAILABLE;

2374

2204

goto end;

2395

2225

goto end;

2396

2226

}

2397

2227

2398

in_port_t port;

2228

uint16_t port;

2399

2229

errno = 0;

2400

2230

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

2401

2231

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

2402

or tmpmax != (in_port_t)tmpmax){

2232

or tmpmax != (uint16_t)tmpmax){

2403

2233

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

2404

2234

exitcode = EX_USAGE;

2405

2235

goto end;

2406

2236

}

2407

2237

2408

2238

if(quit_now){

2409

2239

goto end;

2410

2240

}

2411

2241

2412

port = (in_port_t)tmpmax;

2242

port = (uint16_t)tmpmax;

2413

2243

*address = '\0';

2414

2244

/* Colon in address indicates IPv6 */

2415

2245

int af;

2431

2261

}

2432

2262

2433

2263

while(not quit_now){

2434

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

2435

&mc);

2264

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

2436

2265

if(quit_now or ret == 0){

2437

2266

break;

2438

2267

}

2440

2269

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

2441

2270

(int)retry_interval);

2442

2271

}

2443

sleep((unsigned int)retry_interval);

2272

sleep((int)retry_interval);

2444

2273

}

2445

2274

2446

if(not quit_now){

2275

if (not quit_now){

2447

2276

exitcode = EXIT_SUCCESS;

2448

2277

}

2449

2278

2464

2293

config.publish_domain = 0;

2465

2294

2466

2295

/* Allocate a new server */

2467

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2468

&config, NULL, NULL, &ret_errno);

2296

mc.server = avahi_server_new(avahi_simple_poll_get

2297

(mc.simple_poll), &config, NULL,

2298

NULL, &ret_errno);

2469

2299

2470

2300

/* Free the Avahi configuration data */

2471

2301

avahi_server_config_free(&config);

2486

2316

/* Create the Avahi service browser */

2487

2317

sb = avahi_s_service_browser_new(mc.server, if_index,

2488

2318

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2489

NULL, 0, browse_callback,

2490

(void *)&mc);

2319

NULL, 0, browse_callback, NULL);

2491

2320

if(sb == NULL){

2492

2321

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

2493

2322

avahi_strerror(avahi_server_errno(mc.server)));

2504

2333

if(debug){

2505

2334

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

2506

2335

}

2507

2508

ret = avahi_loop_with_timeout(simple_poll,

2509

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

2336

2337

ret = avahi_loop_with_timeout(mc.simple_poll,

2338

(int)(retry_interval * 1000));

2510

2339

if(debug){

2511

2340

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

2512

2341

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

2519

2348

}

2520

2349

2521

2350

/* Cleanup things */

2522

free(mc.interfaces);

2523

2524

2351

if(sb != NULL)

2525

2352

avahi_s_service_browser_free(sb);

2526

2353

2527

2354

if(mc.server != NULL)

2528

2355

avahi_server_free(mc.server);

2529

2356

2530

if(simple_poll != NULL)

2531

avahi_simple_poll_free(simple_poll);

2357

if(mc.simple_poll != NULL)

2358

avahi_simple_poll_free(mc.simple_poll);

2532

2359

2533

2360

if(gnutls_initialized){

2534

2361

gnutls_certificate_free_credentials(mc.cred);

2551

2378

}

2552

2379

}

2553

2380

2554

/* Re-raise privileges */

2381

/* Re-raise priviliges */

2555

2382

{

2556

ret_errno = raise_privileges();

2557

if(ret_errno != 0){

2558

errno = ret_errno;

2559

perror_plus("Failed to raise privileges");

2560

} else {

2561

2562

/* Run network hooks */

2563

run_network_hooks("stop", interfaces_hooks != NULL ?

2564

interfaces_hooks : "", delay);

2565

2566

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

2567

{

2568

char *interface = NULL;

2569

while((interface=argz_next(interfaces_to_take_down,

2570

interfaces_to_take_down_size,

2571

interface))){

2572

ret_errno = take_down_interface(interface);

2573

if(ret_errno != 0){

2574

errno = ret_errno;

2575

perror_plus("Failed to take down interface");

2576

}

2577

}

2578

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

2579

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

2580

" down\n");

2581

}

2582

}

2583

}

2584

2585

ret_errno = lower_privileges_permanently();

2586

if(ret_errno != 0){

2587

errno = ret_errno;

2588

perror_plus("Failed to lower privileges permanently");

2589

}

2383

raise_privileges();

2384

2385

/* Run network hooks */

2386

run_network_hooks("stop", interfaces_hooks, delay);

2387

2388

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

2389

{

2390

char *interface = NULL;

2391

while((interface=argz_next(interfaces_to_take_down,

2392

interfaces_to_take_down_size,

2393

interface))){

2394

ret_errno = take_down_interface(interface);

2395

if(ret_errno != 0){

2396

errno = ret_errno;

2397

perror_plus("Failed to take down interface");

2398

}

2399

}

2400

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

2401

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

2402

" down\n");

2403

}

2404

}

2405

2406

lower_privileges_permanently();

2590

2407

}

2591

2408

2592

2409

free(interfaces_to_take_down);

2593

2410

free(interfaces_hooks);

2594

2411

2595

2412

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

2596

if(tempdir != NULL){

2413

if(tempdir_created){

2597

2414

struct dirent **direntries = NULL;

2598

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

2599

O_NOFOLLOW));

2600

if(tempdir_fd == -1){

2601

perror_plus("open");

2602

} else {

2603

#ifdef __GLIBC__

2604

#if __GLIBC_PREREQ(2, 15)

2605

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

2606

notdotentries, alphasort);

2607

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

2608

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

2609

alphasort);

2610

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

2611

#else /* not __GLIBC__ */

2612

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

2613

alphasort);

2614

#endif /* not __GLIBC__ */

2615

if(numentries >= 0){

2616

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

2617

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

2618

if(ret == -1){

2619

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

2620

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

2621

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

2622

}

2623

}

2624

2625

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

2626

free(direntries);

2627

if(numentries == -1){

2628

perror_plus("scandir");

2629

}

2630

ret = rmdir(tempdir);

2631

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

2632

perror_plus("rmdir");

2633

}

2415

struct dirent *direntry = NULL;

2416

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

2417

alphasort);

2418

if (numentries > 0){

2419

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

2420

direntry = direntries[i];

2421

char *fullname = NULL;

2422

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

2423

direntry->d_name);

2424

if(ret < 0){

2425

perror_plus("asprintf");

2426

continue;

2427

}

2428

ret = remove(fullname);

2429

if(ret == -1){

2430

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

2431

strerror(errno));

2432

}

2433

free(fullname);

2634

2434

}

2635

TEMP_FAILURE_RETRY(close(tempdir_fd));

2435

}

2436

2437

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

2438

free(direntries);

2439

if (numentries == -1){

2440

perror_plus("scandir");

2441

}

2442

ret = rmdir(tempdir);

2443

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

2444

perror_plus("rmdir");

2636

2445

}

2637

2446

}

2638

2447