/mandos/trunk : revision 734

9

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

10

*

11

* Everything else is

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13

12

13

14

*

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

16

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif

35

#endif /* not _LARGEFILE_SOURCE */

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif

38

#endif /* not _FILE_OFFSET_BITS */

39

40

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

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

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stdout, ferror(), remove() */

43

stdout, ferror() */

44

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

45

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

46

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

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opendir(), DIR */

56

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

57

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

60

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

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61

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

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62

*/

62

63

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

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73

*/

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() */

76

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

76

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

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unlinkat() */

78

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

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

78

80

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

79

81

argp_state, struct argp,

91

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argz_delete(), argz_append(),

92

94

argz_stringify(), argz_add(),

93

95

argz_count() */

96

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

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EAI_SYSTEM, gai_strerror() */

94

98

95

99

#ifdef __linux__

96

100

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

138

142

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

139

143

char *connect_to = NULL;

140

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

141

146

uid_t uid = 65534;

142

147

gid_t gid = 65534;

143

148

161

166

const char *priority;

162

167

gpgme_ctx_t ctx;

163

168

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

164

171

} mandos_context;

165

172

166

173

/* global so signal handler can reach it*/

167

174

AvahiSimplePoll *simple_poll;

168

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

169

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

170

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

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175

172

176

sig_atomic_t quit_now = 0;

173

177

int signal_received = 0;

181

185

perror(print_text);

182

186

}

183

187

184

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

188

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

185

189

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

186

190

va_list ap;

187

191

va_start (ap, format);

188

192

189

193

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

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194

program_invocation_short_name));

191

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

195

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

192

196

}

193

197

194

198

/*

196

200

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

197

201

* "buffer_length" is how much is already used.

198

202

*/

203

__attribute__((nonnull, warn_unused_result))

199

204

size_t incbuffer(char **buffer, size_t buffer_length,

200

205

size_t buffer_capacity){

201

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

202

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

203

if(buffer == NULL){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

204

213

return 0;

205

214

}

215

*buffer = new_buf;

206

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buffer_capacity += BUFFER_SIZE;

207

217

}

208

218

return buffer_capacity;

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219

}

210

220

211

221

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

222

__attribute__((nonnull, warn_unused_result))

212

223

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

213

int af){

224

int af, server **current_server){

214

225

int ret;

215

226

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

216

227

if(new_server == NULL){

223

234

.af = af };

224

235

if(new_server->ip == NULL){

225

236

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);

226

252

return false;

227

253

}

228

254

/* Special case of first server */

229

if (mc.current_server == NULL){

255

if(*current_server == NULL){

230

256

new_server->next = new_server;

231

257

new_server->prev = new_server;

232

mc.current_server = new_server;

233

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

258

*current_server = new_server;

234

259

} else {

235

new_server->next = mc.current_server;

236

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

260

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

261

new_server->next = *current_server;

262

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

237

263

new_server->prev->next = new_server;

238

mc.current_server->prev = new_server;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

return false;

264

(*current_server)->prev = new_server;

244

265

}

245

266

return true;

246

267

}

248

269

/*

249

270

* Initialize GPGME.

250

271

*/

251

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

252

const char *tempdir){

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

253

277

gpgme_error_t rc;

254

278

gpgme_engine_info_t engine_info;

255

279

256

280

/*

257

281

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

258

282

*/

259

bool import_key(const char *filename){

283

bool import_key(const char * const filename){

260

284

int ret;

261

285

int fd;

262

286

gpgme_data_t pgp_data;

274

298

return false;

275

299

}

276

300

277

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

278

302

if(rc != GPG_ERR_NO_ERROR){

279

303

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

280

304

gpgme_strsource(rc), gpgme_strerror(rc));

324

348

}

325

349

326

350

/* Create new GPGME "context" */

327

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

351

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

328

352

if(rc != GPG_ERR_NO_ERROR){

329

353

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

330

354

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

343

367

* Decrypt OpenPGP data.

344

368

* Returns -1 on error

345

369

*/

370

__attribute__((nonnull, warn_unused_result))

346

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

347

372

size_t crypto_size,

348

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

349

375

gpgme_data_t dh_crypto, dh_plain;

350

376

gpgme_error_t rc;

351

377

ssize_t ret;

377

403

378

404

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

379

405

data buffer */

380

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

406

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

381

407

if(rc != GPG_ERR_NO_ERROR){

382

408

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

383

409

gpgme_strsource(rc), gpgme_strerror(rc));

384

410

plaintext_length = -1;

385

411

if(debug){

386

412

gpgme_decrypt_result_t result;

387

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

388

414

if(result == NULL){

389

415

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

390

416

} else {

467

493

return plaintext_length;

468

494

}

469

495

470

static const char * safer_gnutls_strerror(int value){

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

471

498

const char *ret = gnutls_strerror(value);

472

499

if(ret == NULL)

473

500

ret = "(unknown)";

475

502

}

476

503

477

504

/* GnuTLS log function callback */

505

__attribute__((nonnull))

478

506

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

479

507

const char* string){

480

508

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

481

509

}

482

510

511

__attribute__((nonnull, warn_unused_result))

483

512

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename){

513

const char *seckeyfilename,

514

mandos_context *mc){

485

515

int ret;

486

516

487

517

if(debug){

504

534

}

505

535

506

536

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

508

538

if(ret != GNUTLS_E_SUCCESS){

509

539

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

510

540

safer_gnutls_strerror(ret));

520

550

}

521

551

522

552

ret = gnutls_certificate_set_openpgp_key_file

523

(mc.cred, pubkeyfilename, seckeyfilename,

553

(mc->cred, pubkeyfilename, seckeyfilename,

524

554

GNUTLS_OPENPGP_FMT_BASE64);

525

555

if(ret != GNUTLS_E_SUCCESS){

526

556

fprintf_plus(stderr,

532

562

}

533

563

534

564

/* GnuTLS server initialization */

535

ret = gnutls_dh_params_init(&mc.dh_params);

565

ret = gnutls_dh_params_init(&mc->dh_params);

536

566

if(ret != GNUTLS_E_SUCCESS){

537

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

568

" initialization: %s\n",

539

569

safer_gnutls_strerror(ret));

540

570

goto globalfail;

541

571

}

542

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

572

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

543

573

if(ret != GNUTLS_E_SUCCESS){

544

574

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

545

575

safer_gnutls_strerror(ret));

546

576

goto globalfail;

547

577

}

548

578

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

579

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

550

580

551

581

return 0;

552

582

553

583

globalfail:

554

584

555

gnutls_certificate_free_credentials(mc.cred);

585

gnutls_certificate_free_credentials(mc->cred);

556

586

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

587

gnutls_dh_params_deinit(mc->dh_params);

558

588

return -1;

559

589

}

560

590

561

static int init_gnutls_session(gnutls_session_t *session){

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

562

594

int ret;

563

595

/* GnuTLS session creation */

564

596

do {

576

608

{

577

609

const char *err;

578

610

do {

579

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

611

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

580

612

if(quit_now){

581

613

gnutls_deinit(*session);

582

614

return -1;

593

625

594

626

do {

595

627

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

628

mc->cred);

597

629

if(quit_now){

598

630

gnutls_deinit(*session);

599

631

return -1;

609

641

/* ignore client certificate if any. */

610

642

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

643

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

613

645

614

646

return 0;

615

647

}

619

651

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

620

652

621

653

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

622

655

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

623

656

AvahiIfIndex if_index,

624

int af){

657

int af, mandos_context *mc){

625

658

int ret, tcp_sd = -1;

626

659

ssize_t sret;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

660

struct sockaddr_storage to;

631

661

char *buffer = NULL;

632

662

char *decrypted_buffer = NULL;

633

663

size_t buffer_length = 0;

657

687

return -1;

658

688

}

659

689

660

ret = init_gnutls_session(&session);

690

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

691

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

692

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

693

bool match = false;

694

{

695

char *interface = NULL;

696

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

697

interface))){

698

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

699

match = true;

700

break;

701

}

702

}

703

}

704

if(not match){

705

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

706

connect to the server */

707

if(debug){

708

char interface[IF_NAMESIZE];

709

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

710

perror_plus("if_indextoname");

711

} else {

712

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

713

" \"%s\"\n",

714

if_indextoname((unsigned int)if_index,

715

interface));

716

}

717

}

718

return -1;

719

}

720

}

721

722

ret = init_gnutls_session(&session, mc);

661

723

if(ret != 0){

662

724

return -1;

663

725

}

682

744

683

745

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

684

746

if(af == AF_INET6){

685

to.in6.sin6_family = (sa_family_t)af;

686

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

747

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

748

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

687

749

} else { /* IPv4 */

688

to.in.sin_family = (sa_family_t)af;

689

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

750

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

751

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

690

752

}

691

753

if(ret < 0 ){

692

754

int e = errno;

701

763

goto mandos_end;

702

764

}

703

765

if(af == AF_INET6){

704

to.in6.sin6_port = htons(port);

705

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

706

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

707

-Wunreachable-code*/

766

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

767

if(IN6_IS_ADDR_LINKLOCAL

768

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

708

769

if(if_index == AVAHI_IF_UNSPEC){

709

770

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

710

771

" incomplete without a network interface\n");

712

773

goto mandos_end;

713

774

}

714

775

/* Set the network interface number as scope */

715

to.in6.sin6_scope_id = (uint32_t)if_index;

776

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

716

777

}

717

778

} else {

718

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

719

-Wconversion and

720

-Wunreachable-code */

779

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

721

780

}

722

781

723

782

if(quit_now){

740

799

}

741

800

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

742

801

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

743

const char *pcret;

744

802

if(af == AF_INET6){

745

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

746

sizeof(addrstr));

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

747

807

} else {

748

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

749

sizeof(addrstr));

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

750

812

}

751

if(pcret == NULL){

752

perror_plus("inet_ntop");

753

} else {

754

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

755

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

756

}

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);

757

819

}

758

820

}

759

821

763

825

}

764

826

765

827

if(af == AF_INET6){

766

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

828

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

829

sizeof(struct sockaddr_in6));

767

830

} else {

768

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

831

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

832

sizeof(struct sockaddr_in));

769

833

}

770

834

if(ret < 0){

771

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

835

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

772

836

int e = errno;

773

837

perror_plus("connect");

774

838

errno = e;

935

999

if(buffer_length > 0){

936

1000

ssize_t decrypted_buffer_size;

937

1001

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

938

&decrypted_buffer);

1002

&decrypted_buffer, mc);

939

1003

if(decrypted_buffer_size >= 0){

940

1004

941

1005

written = 0;

989

1053

return retval;

990

1054

}

991

1055

1056

__attribute__((nonnull))

992

1057

static void resolve_callback(AvahiSServiceResolver *r,

993

1058

AvahiIfIndex interface,

994

1059

AvahiProtocol proto,

1002

1067

AVAHI_GCC_UNUSED AvahiStringList *txt,

1003

1068

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1004

1069

flags,

1005

AVAHI_GCC_UNUSED void* userdata){

1070

void *mc){

1006

1071

if(r == NULL){

1007

1072

return;

1008

1073

}

1011

1076

timed out */

1012

1077

1013

1078

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1014

1080

return;

1015

1081

}

1016

1082

1020

1086

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

1021

1087

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

1022

1088

domain,

1023

avahi_strerror(avahi_server_errno(mc.server)));

1089

avahi_strerror(avahi_server_errno

1090

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

1024

1091

break;

1025

1092

1026

1093

case AVAHI_RESOLVER_FOUND:

1034

1101

}

1035

1102

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

1036

1103

interface,

1037

avahi_proto_to_af(proto));

1104

avahi_proto_to_af(proto),

1105

mc);

1038

1106

if(ret == 0){

1039

1107

avahi_simple_poll_quit(simple_poll);

1040

1108

} else {

1041

1109

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

1042

avahi_proto_to_af(proto))){

1110

avahi_proto_to_af(proto),

1111

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

1043

1112

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

1044

1113

" list\n", name);

1045

1114

}

1058

1127

const char *domain,

1059

1128

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1129

flags,

1061

AVAHI_GCC_UNUSED void* userdata){

1130

void *mc){

1062

1131

if(b == NULL){

1063

1132

return;

1064

1133

}

1075

1144

case AVAHI_BROWSER_FAILURE:

1076

1145

1077

1146

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

1078

avahi_strerror(avahi_server_errno(mc.server)));

1147

avahi_strerror(avahi_server_errno

1148

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

1079

1149

avahi_simple_poll_quit(simple_poll);

1080

1150

return;

1081

1151

1085

1155

the callback function is called the Avahi server will free the

1086

1156

resolver for us. */

1087

1157

1088

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

1089

name, type, domain, protocol, 0,

1090

resolve_callback, NULL) == NULL)

1158

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

1159

interface, protocol, name, type,

1160

domain, protocol, 0,

1161

resolve_callback, mc) == NULL)

1091

1162

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

1092

1163

" %s\n", name,

1093

avahi_strerror(avahi_server_errno(mc.server)));

1164

avahi_strerror(avahi_server_errno

1165

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

1094

1166

break;

1095

1167

1096

1168

case AVAHI_BROWSER_REMOVE:

1121

1193

errno = old_errno;

1122

1194

}

1123

1195

1196

__attribute__((nonnull, warn_unused_result))

1124

1197

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

1125

1198

int ret;

1126

1199

error_t ret_errno;

1145

1218

return true;

1146

1219

}

1147

1220

1221

__attribute__((nonnull, warn_unused_result))

1148

1222

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

1149

1223

1150

1224

/* Reject the loopback device */

1192

1266

* corresponds to an acceptable network device.

1193

1267

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

1194

1268

*/

1269

__attribute__((nonnull, warn_unused_result))

1195

1270

int good_interface(const struct dirent *if_entry){

1196

1271

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

1197

1272

return 0;

1215

1290

/*

1216

1291

* This function determines if a network interface is up.

1217

1292

*/

1293

__attribute__((nonnull, warn_unused_result))

1218

1294

bool interface_is_up(const char *interface){

1219

1295

struct ifreq ifr;

1220

1296

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

1231

1307

/*

1232

1308

* This function determines if a network interface is running

1233

1309

*/

1310

__attribute__((nonnull, warn_unused_result))

1234

1311

bool interface_is_running(const char *interface){

1235

1312

struct ifreq ifr;

1236

1313

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

1244

1321

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

1245

1322

}

1246

1323

1324

__attribute__((nonnull, pure, warn_unused_result))

1247

1325

int notdotentries(const struct dirent *direntry){

1248

1326

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

1249

1327

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

1256

1334

}

1257

1335

1258

1336

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

1337

__attribute__((nonnull, warn_unused_result))

1259

1338

int runnable_hook(const struct dirent *direntry){

1260

1339

int ret;

1261

1340

size_t sret;

1269

1348

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

1270

1349

"abcdefghijklmnopqrstuvwxyz"

1271

1350

"0123456789"

1272

"_-");

1351

"_.-");

1273

1352

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

1274

1353

/* Contains non-allowed characters */

1275

1354

if(debug){

1279

1358

return 0;

1280

1359

}

1281

1360

1282

char *fullname = NULL;

1283

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

1284

if(ret < 0){

1285

perror_plus("asprintf");

1286

return 0;

1287

}

1288

1289

ret = stat(fullname, &st);

1361

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

1290

1362

if(ret == -1){

1291

1363

if(debug){

1292

1364

perror_plus("Could not stat hook");

1316

1388

return 1;

1317

1389

}

1318

1390

1319

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1320

1394

int ret;

1321

1395

struct timespec now;

1322

1396

struct timespec waited_time;

1323

1397

intmax_t block_time;

1324

1398

1325

1399

while(true){

1326

if(mc.current_server == NULL){

1327

if (debug){

1400

if(mc->current_server == NULL){

1401

if(debug){

1328

1402

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

1329

1403

" No timeout!\n");

1330

1404

}

1331

1405

ret = avahi_simple_poll_iterate(s, -1);

1332

1406

} else {

1333

if (debug){

1407

if(debug){

1334

1408

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

1335

1409

" it, or wait\n");

1336

1410

}

1343

1417

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

1344

1418

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

1345

1419

waited_time.tv_sec = (now.tv_sec

1346

- mc.current_server->last_seen.tv_sec);

1420

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

1347

1421

waited_time.tv_nsec = (now.tv_nsec

1348

- mc.current_server->last_seen.tv_nsec);

1422

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

1349

1423

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

1350

1424

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

1351

1425

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

1353

1427

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

1354

1428

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

1355

1429

1356

if (debug){

1430

if(debug){

1357

1431

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

1358

1432

block_time);

1359

1433

}

1360

1434

1361

1435

if(block_time <= 0){

1362

ret = start_mandos_communication(mc.current_server->ip,

1363

mc.current_server->port,

1364

mc.current_server->if_index,

1365

mc.current_server->af);

1436

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

1437

mc->current_server->port,

1438

mc->current_server->if_index,

1439

mc->current_server->af, mc);

1366

1440

if(ret == 0){

1367

avahi_simple_poll_quit(simple_poll);

1441

avahi_simple_poll_quit(s);

1368

1442

return 0;

1369

1443

}

1370

1444

ret = clock_gettime(CLOCK_MONOTONIC,

1371

&mc.current_server->last_seen);

1445

&mc->current_server->last_seen);

1372

1446

if(ret == -1){

1373

1447

perror_plus("clock_gettime");

1374

1448

return -1;

1375

1449

}

1376

mc.current_server = mc.current_server->next;

1450

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

1377

1451

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

1378

1452

servers, but don't block */

1379

1453

}

1381

1455

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

1382

1456

}

1383

1457

if(ret != 0){

1384

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

1458

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

1385

1459

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

1386

1460

}

1387

1461

}

1389

1463

}

1390

1464

1391

1465

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

1466

__attribute__((warn_unused_result))

1392

1467

error_t raise_privileges(void){

1393

1468

error_t old_errno = errno;

1394

1469

error_t ret_errno = 0;

1395

1470

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

1396

1471

ret_errno = errno;

1397

perror_plus("seteuid");

1398

1472

}

1399

1473

errno = old_errno;

1400

1474

return ret_errno;

1401

1475

}

1402

1476

1403

1477

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

1478

__attribute__((warn_unused_result))

1404

1479

error_t raise_privileges_permanently(void){

1405

1480

error_t old_errno = errno;

1406

1481

error_t ret_errno = raise_privileges();

1410

1485

}

1411

1486

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

1412

1487

ret_errno = errno;

1413

perror_plus("seteuid");

1414

1488

}

1415

1489

errno = old_errno;

1416

1490

return ret_errno;

1417

1491

}

1418

1492

1419

1493

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

1494

__attribute__((warn_unused_result))

1420

1495

error_t lower_privileges(void){

1421

1496

error_t old_errno = errno;

1422

1497

error_t ret_errno = 0;

1423

1498

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

1424

1499

ret_errno = errno;

1425

perror_plus("seteuid");

1426

1500

}

1427

1501

errno = old_errno;

1428

1502

return ret_errno;

1429

1503

}

1430

1504

1431

1505

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1432

1507

error_t lower_privileges_permanently(void){

1433

1508

error_t old_errno = errno;

1434

1509

error_t ret_errno = 0;

1435

1510

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

1436

1511

ret_errno = errno;

1437

perror_plus("setuid");

1438

1512

}

1439

1513

errno = old_errno;

1440

1514

return ret_errno;

1441

1515

}

1442

1516

1443

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

1517

__attribute__((nonnull))

1518

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

1444

1519

const float delay){

1445

struct dirent **direntries;

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__ */

1547

if(numhooks == -1){

1548

perror_plus("scandir");

1549

return;

1550

}

1446

1551

struct dirent *direntry;

1447

1552

int ret;

1448

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

1449

alphasort);

1450

if(numhooks == -1){

1451

if(errno == ENOENT){

1452

if(debug){

1453

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

1454

" found\n", hookdir);

1455

}

1456

} else {

1457

perror_plus("scandir");

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);

1458

1559

}

1459

} else {

1460

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

1461

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

1462

direntry = direntries[i];

1463

char *fullname = NULL;

1464

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

1465

if(ret < 0){

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){

1466

1621

perror_plus("asprintf");

1467

continue;

1468

}

1469

if(debug){

1470

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

1471

direntry->d_name);

1472

}

1473

pid_t hook_pid = fork();

1474

if(hook_pid == 0){

1475

/* Child */

1476

/* Raise privileges */

1477

raise_privileges_permanently();

1478

/* Set group */

1479

errno = 0;

1480

ret = setgid(0);

1481

if(ret == -1){

1482

perror_plus("setgid");

1483

}

1484

/* Reset supplementary groups */

1485

errno = 0;

1486

ret = setgroups(0, NULL);

1487

if(ret == -1){

1488

perror_plus("setgroups");

1489

}

1490

dup2(devnull, STDIN_FILENO);

1491

close(devnull);

1492

dup2(STDERR_FILENO, STDOUT_FILENO);

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

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

1509

if(ret == -1){

1510

perror_plus("setenv");

1511

_exit(EX_OSERR);

1512

}

1513

char *delaystring;

1514

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

1515

if(ret == -1){

1516

perror_plus("asprintf");

1517

_exit(EX_OSERR);

1518

}

1519

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

1520

if(ret == -1){

1521

free(delaystring);

1522

perror_plus("setenv");

1523

_exit(EX_OSERR);

1524

}

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

if(ret == -1){

1525

1626

free(delaystring);

1526

if(connect_to != NULL){

1527

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

1528

if(ret == -1){

1529

perror_plus("setenv");

1530

_exit(EX_OSERR);

1531

}

1532

}

1533

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

1534

perror_plus("execl");

1535

_exit(EXIT_FAILURE);

1536

}

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

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

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

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

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

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

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

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

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

if(hook_pid == -1){

1654

perror_plus("fork");

1655

free(direntry);

1656

continue;

1657

}

1658

int status;

1659

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

1660

perror_plus("waitpid");

1661

free(direntry);

1662

continue;

1663

}

1664

if(WIFEXITED(status)){

1665

if(WEXITSTATUS(status) != 0){

1666

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

1667

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

1668

WEXITSTATUS(status));

1669

free(direntry);

1670

continue;

1671

}

1672

} else if(WIFSIGNALED(status)){

1673

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

1674

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

1675

WTERMSIG(status));

1676

free(direntry);

1677

continue;

1537

1678

} else {

1538

int status;

1539

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

1540

perror_plus("waitpid");

1541

free(fullname);

1542

continue;

1543

}

1544

if(WIFEXITED(status)){

1545

if(WEXITSTATUS(status) != 0){

1546

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

1547

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

1548

WEXITSTATUS(status));

1549

free(fullname);

1550

continue;

1551

}

1552

} else if(WIFSIGNALED(status)){

1553

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

1554

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

1555

WTERMSIG(status));

1556

free(fullname);

1557

continue;

1558

} else {

1559

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

1560

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

1561

free(fullname);

1562

continue;

1563

}

1564

}

1565

free(fullname);

1566

if(debug){

1567

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

1568

direntry->d_name);

1569

}

1570

}

1571

close(devnull);

1572

}

1573

return true;

1679

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

1680

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

1681

free(direntry);

1682

continue;

1683

}

1684

}

1685

if(debug){

1686

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

1687

direntry->d_name);

1688

}

1689

free(direntry);

1690

}

1691

free(direntries);

1692

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

1693

perror_plus("close");

1694

} else {

1695

hookdir_fd = -1;

1696

}

1697

close(devnull);

1574

1698

}

1575

1699

1700

__attribute__((nonnull, warn_unused_result))

1576

1701

error_t bring_up_interface(const char *const interface,

1577

1702

const float delay){

1578

int sd = -1;

1579

1703

error_t old_errno = errno;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1704

int ret;

1582

1705

struct ifreq network;

1583

1706

unsigned int if_index = if_nametoindex(interface);

1584

1707

if(if_index == 0){

1593

1716

}

1594

1717

1595

1718

if(not interface_is_up(interface)){

1596

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

1719

error_t ret_errno = 0, ioctl_errno = 0;

1720

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

1597

1721

ret_errno = errno;

1598

1722

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

1599

1723

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

1724

errno = old_errno;

1600

1725

return ret_errno;

1601

1726

}

1602

network.ifr_flags |= IFF_UP;

1727

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

1603

1728

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1729

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

1730

if(sd == -1){

1606

1731

ret_errno = errno;

1607

1732

perror_plus("socket");

1608

1733

errno = old_errno;

1609

1734

return ret_errno;

1610

1735

}

1611

1736

1612

1737

if(quit_now){

1613

close(sd);

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1614

1742

errno = old_errno;

1615

1743

return EINTR;

1616

1744

}

1620

1748

interface);

1621

1749

}

1622

1750

1623

/* Raise priviliges */

1624

raise_privileges();

1751

/* Raise privileges */

1752

ret_errno = raise_privileges();

1753

if(ret_errno != 0){

1754

errno = ret_errno;

1755

perror_plus("Failed to raise privileges");

1756

}

1625

1757

1626

1758

#ifdef __linux__

1627

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1628

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

1629

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

1630

bool restore_loglevel = true;

1631

if(ret_linux == -1){

1632

restore_loglevel = false;

1633

perror_plus("klogctl");

1759

int ret_linux;

1760

bool restore_loglevel = false;

1761

if(ret_errno == 0){

1762

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1763

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

1764

ret_linux = klogctl(8, NULL, 5);

1765

if(ret_linux == -1){

1766

perror_plus("klogctl");

1767

} else {

1768

restore_loglevel = true;

1769

}

1634

1770

}

1635

1771

#endif /* __linux__ */

1636

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

1637

ret_errno = errno;

1772

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

1773

ioctl_errno = errno;

1638

1774

#ifdef __linux__

1639

1775

if(restore_loglevel){

1640

1776

ret_linux = klogctl(7, NULL, 0);

1644

1780

}

1645

1781

#endif /* __linux__ */

1646

1782

1647

/* Lower privileges */

1648

lower_privileges();

1783

/* If raise_privileges() succeeded above */

1784

if(ret_errno == 0){

1785

/* Lower privileges */

1786

ret_errno = lower_privileges();

1787

if(ret_errno != 0){

1788

errno = ret_errno;

1789

perror_plus("Failed to lower privileges");

1790

}

1791

}

1649

1792

1650

1793

/* Close the socket */

1651

1794

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

1654

1797

}

1655

1798

1656

1799

if(ret_setflags == -1){

1657

errno = ret_errno;

1800

errno = ioctl_errno;

1658

1801

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1659

1802

errno = old_errno;

1660

return ret_errno;

1803

return ioctl_errno;

1661

1804

}

1662

1805

} else if(debug){

1663

1806

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

1681

1824

return 0;

1682

1825

}

1683

1826

1827

__attribute__((nonnull, warn_unused_result))

1684

1828

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1686

1829

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1689

1830

struct ifreq network;

1690

1831

unsigned int if_index = if_nametoindex(interface);

1691

1832

if(if_index == 0){

1694

1835

return ENXIO;

1695

1836

}

1696

1837

if(interface_is_up(interface)){

1838

error_t ret_errno = 0, ioctl_errno = 0;

1697

1839

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

1698

1840

ret_errno = errno;

1699

1841

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

1700

1842

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

1843

errno = old_errno;

1701

1844

return ret_errno;

1702

1845

}

1703

1846

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

1704

1847

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1848

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

1849

if(sd == -1){

1707

1850

ret_errno = errno;

1708

1851

perror_plus("socket");

1709

1852

errno = old_errno;

1715

1858

interface);

1716

1859

}

1717

1860

1718

/* Raise priviliges */

1719

raise_privileges();

1720

1721

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

1722

ret_errno = errno;

1723

1724

/* Lower privileges */

1725

lower_privileges();

1861

/* Raise privileges */

1862

ret_errno = raise_privileges();

1863

if(ret_errno != 0){

1864

errno = ret_errno;

1865

perror_plus("Failed to raise privileges");

1866

}

1867

1868

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

1869

ioctl_errno = errno;

1870

1871

/* If raise_privileges() succeeded above */

1872

if(ret_errno == 0){

1873

/* Lower privileges */

1874

ret_errno = lower_privileges();

1875

if(ret_errno != 0){

1876

errno = ret_errno;

1877

perror_plus("Failed to lower privileges");

1878

}

1879

}

1726

1880

1727

1881

/* Close the socket */

1728

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

1882

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

1729

1883

if(ret == -1){

1730

1884

perror_plus("close");

1731

1885

}

1732

1886

1733

1887

if(ret_setflags == -1){

1734

errno = ret_errno;

1888

errno = ioctl_errno;

1735

1889

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1736

1890

errno = old_errno;

1737

return ret_errno;

1891

return ioctl_errno;

1738

1892

}

1739

1893

} else if(debug){

1740

1894

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

1746

1900

}

1747

1901

1748

1902

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

1903

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

1904

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

1905

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

1906

.interfaces = NULL, .interfaces_size = 0 };

1749

1907

AvahiSServiceBrowser *sb = NULL;

1750

1908

error_t ret_errno;

1751

1909

int ret;

1752

1910

intmax_t tmpmax;

1753

1911

char *tmp;

1754

1912

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1757

1913

char *interfaces_to_take_down = NULL;

1758

1914

size_t interfaces_to_take_down_size = 0;

1759

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

1760

bool tempdir_created = false;

1915

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

1916

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

1917

char *tempdir = NULL;

1761

1918

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1762

1919

const char *seckey = PATHDIR "/" SECKEY;

1763

1920

const char *pubkey = PATHDIR "/" PUBKEY;

1764

1921

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1766

1922

1767

1923

bool gnutls_initialized = false;

1768

1924

bool gpgme_initialized = false;

1859

2015

connect_to = arg;

1860

2016

break;

1861

2017

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

1862

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

1863

(int)',');

2018

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

2019

arg, (int)',');

1864

2020

if(ret_errno != 0){

1865

2021

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

1866

2022

}

1946

2102

/* Work around Debian bug #633582:

1947

2103

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

1948

2104

1949

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

2105

/* Re-raise privileges */

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2109

perror_plus("Failed to raise privileges");

2110

} else {

1951

2111

struct stat st;

1952

2112

1953

2113

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

1993

2153

}

1994

2154

1995

2155

/* Lower privileges */

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2159

perror_plus("Failed to lower privileges");

2000

2160

}

2001

2161

}

2002

2162

}

2003

2163

2004

/* Remove empty interface names */

2164

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

2005

2165

{

2006

2166

char *interface = NULL;

2007

while((interface = argz_next(interfaces, interfaces_size,

2167

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

2008

2168

interface))){

2009

if(if_nametoindex(interface) == 0){

2010

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

2169

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

2170

and if_nametoindex(interface) == 0){

2171

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

2011

2172

fprintf_plus(stderr, "Not using nonexisting interface"

2012

2173

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

2013

2174

}

2014

argz_delete(&interfaces, &interfaces_size, interface);

2175

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

2015

2176

interface = NULL;

2016

2177

}

2017

2178

}

2019

2180

2020

2181

/* Run network hooks */

2021

2182

{

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2183

if(mc.interfaces != NULL){

2184

interfaces_hooks = malloc(mc.interfaces_size);

2025

2185

if(interfaces_hooks == NULL){

2026

2186

perror_plus("malloc");

2027

2187

goto end;

2028

2188

}

2029

memcpy(interfaces_hooks, interfaces, interfaces_size);

2030

interfaces_hooks_size = interfaces_size;

2031

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2032

(int)',');

2033

}

2034

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

2035

interfaces_hooks : "", delay)){

2036

goto end;

2037

}

2189

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

2190

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

2191

}

2192

run_network_hooks("start", interfaces_hooks != NULL ?

2193

interfaces_hooks : "", delay);

2038

2194

}

2039

2195

2040

2196

if(not debug){

2117

2273

}

2118

2274

2119

2275

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

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2276

if(mc.interfaces == NULL){

2277

struct dirent **direntries = NULL;

2122

2278

/* Look for any good interfaces */

2123

2279

ret = scandir(sys_class_net, &direntries, good_interface,

2124

2280

alphasort);

2125

2281

if(ret >= 1){

2126

2282

/* Add all found interfaces to interfaces list */

2127

2283

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2284

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

2129

2285

direntries[i]->d_name);

2130

2286

if(ret_errno != 0){

2287

errno = ret_errno;

2131

2288

perror_plus("argz_add");

2289

free(direntries[i]);

2132

2290

continue;

2133

2291

}

2134

2292

if(debug){

2135

2293

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

2136

2294

direntries[i]->d_name);

2137

2295

}

2296

free(direntries[i]);

2138

2297

}

2139

2298

free(direntries);

2140

2299

} else {

2141

free(direntries);

2300

if(ret == 0){

2301

free(direntries);

2302

}

2142

2303

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

2143

2304

exitcode = EXIT_FAILURE;

2144

2305

goto end;

2145

2306

}

2146

2307

}

2147

2308

2148

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

2149

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

2150

if(debug){

2151

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

2152

interfaces);

2153

}

2154

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2155

}

2156

2157

/* Bring up interfaces which are down */

2158

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

2159

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

2309

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

2310

{

2160

2311

char *interface = NULL;

2161

while((interface = argz_next(interfaces, interfaces_size,

2312

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

2162

2313

interface))){

2314

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

2315

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

2316

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

2317

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

2318

interface);

2319

interface = NULL;

2320

while((interface = argz_next(mc.interfaces,

2321

mc.interfaces_size, interface))){

2322

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

2323

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

2324

interface);

2325

interface = NULL;

2326

}

2327

}

2328

break;

2329

}

2163

2330

bool interface_was_up = interface_is_up(interface);

2164

ret = bring_up_interface(interface, delay);

2331

errno = bring_up_interface(interface, delay);

2165

2332

if(not interface_was_up){

2166

if(ret != 0){

2167

errno = ret;

2333

if(errno != 0){

2168

2334

perror_plus("Failed to bring up interface");

2169

2335

} else {

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

2336

errno = argz_add(&interfaces_to_take_down,

2337

&interfaces_to_take_down_size,

2338

interface);

2339

if(errno != 0){

2340

perror_plus("argz_add");

2341

}

2173

2342

}

2174

2343

}

2175

2344

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2179

2345

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

2180

2346

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

2181

2347

}

2182

2348

}

2183

2349

2350

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

2351

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

2352

if(debug){

2353

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

2354

mc.interfaces);

2355

}

2356

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

2357

}

2358

2184

2359

if(quit_now){

2185

2360

goto end;

2186

2361

}

2187

2362

2188

ret = init_gnutls_global(pubkey, seckey);

2363

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

2189

2364

if(ret == -1){

2190

2365

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

2191

2366

exitcode = EX_UNAVAILABLE;

2198

2373

goto end;

2199

2374

}

2200

2375

2201

if(mkdtemp(tempdir) == NULL){

2376

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

2377

tempdir = mkdtemp(run_tempdir);

2378

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

2379

if(debug){

2380

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

2381

run_tempdir, old_tempdir);

2382

}

2383

tempdir = mkdtemp(old_tempdir);

2384

}

2385

if(tempdir == NULL){

2202

2386

perror_plus("mkdtemp");

2203

2387

goto end;

2204

2388

}

2205

tempdir_created = true;

2206

2389

2207

2390

if(quit_now){

2208

2391

goto end;

2209

2392

}

2210

2393

2211

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

2394

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

2212

2395

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

2213

2396

exitcode = EX_UNAVAILABLE;

2214

2397

goto end;

2244

2427

exitcode = EX_USAGE;

2245

2428

goto end;

2246

2429

}

2247

2430

2248

2431

if(quit_now){

2249

2432

goto end;

2250

2433

}

2271

2454

}

2272

2455

2273

2456

while(not quit_now){

2274

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

2457

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

2458

&mc);

2275

2459

if(quit_now or ret == 0){

2276

2460

break;

2277

2461

}

2279

2463

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

2280

2464

(int)retry_interval);

2281

2465

}

2282

sleep((int)retry_interval);

2466

sleep((unsigned int)retry_interval);

2283

2467

}

2284

2468

2285

if (not quit_now){

2469

if(not quit_now){

2286

2470

exitcode = EXIT_SUCCESS;

2287

2471

}

2288

2472

2325

2509

/* Create the Avahi service browser */

2326

2510

sb = avahi_s_service_browser_new(mc.server, if_index,

2327

2511

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2328

NULL, 0, browse_callback, NULL);

2512

NULL, 0, browse_callback,

2513

(void *)&mc);

2329

2514

if(sb == NULL){

2330

2515

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

2331

2516

avahi_strerror(avahi_server_errno(mc.server)));

2342

2527

if(debug){

2343

2528

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

2344

2529

}

2345

2530

2346

2531

ret = avahi_loop_with_timeout(simple_poll,

2347

(int)(retry_interval * 1000));

2532

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

2348

2533

if(debug){

2349

2534

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

2350

2535

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

2357

2542

}

2358

2543

2359

2544

/* Cleanup things */

2545

free(mc.interfaces);

2546

2360

2547

if(sb != NULL)

2361

2548

avahi_s_service_browser_free(sb);

2362

2549

2382

2569

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

2383

2570

while(mc.current_server != NULL){

2384

2571

server *next = mc.current_server->next;

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic push

2574

#pragma GCC diagnostic ignored "-Wcast-qual"

2575

#endif

2576

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

2577

#ifdef __GNUC__

2578

#pragma GCC diagnostic pop

2579

#endif

2385

2580

free(mc.current_server);

2386

2581

mc.current_server = next;

2387

2582

}

2388

2583

}

2389

2584

2390

/* Re-raise priviliges */

2585

/* Re-raise privileges */

2391

2586

{

2392

raise_privileges();

2393

2394

/* Run network hooks */

2395

run_network_hooks("stop", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

2397

2398

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

2399

{

2400

char *interface = NULL;

2401

while((interface=argz_next(interfaces_to_take_down,

2402

interfaces_to_take_down_size,

2403

interface))){

2404

ret_errno = take_down_interface(interface);

2405

if(ret_errno != 0){

2406

errno = ret_errno;

2407

perror_plus("Failed to take down interface");

2408

}

2409

}

2410

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

2411

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

2412

" down\n");

2413

}

2414

}

2415

2416

lower_privileges_permanently();

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2614

}

2615

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

2619

perror_plus("Failed to lower privileges permanently");

2620

}

2417

2621

}

2418

2622

2419

2623

free(interfaces_to_take_down);

2420

2624

free(interfaces_hooks);

2421

2625

2422

2626

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

2423

if(tempdir_created){

2627

if(tempdir != NULL){

2424

2628

struct dirent **direntries = NULL;

2425

struct dirent *direntry = NULL;

2426

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

2427

alphasort);

2428

if (numentries > 0){

2429

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

2430

direntry = direntries[i];

2431

char *fullname = NULL;

2432

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

2433

direntry->d_name);

2434

if(ret < 0){

2435

perror_plus("asprintf");

2436

continue;

2437

}

2438

ret = remove(fullname);

2439

if(ret == -1){

2440

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

2441

strerror(errno));

2442

}

2443

free(fullname);

2629

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

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

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

2639

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

2640

alphasort);

2641

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

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

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

2649

if(ret == -1){

2650

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

2651

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

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

2444

2666

}

2445

}

2446

2447

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

2448

free(direntries);

2449

if (numentries == -1){

2450

perror_plus("scandir");

2451

}

2452

ret = rmdir(tempdir);

2453

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

2454

perror_plus("rmdir");

2667

TEMP_FAILURE_RETRY(close(tempdir_fd));

2455

2668

}

2456

2669

}

2457

2670