/mandos/release : revision 317

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

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() */

41

42

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

43

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(),

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

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

58

inet_pton(), connect(),

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getnameinfo() */

60

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

60

61

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

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62

*/

62

63

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

72

73

*/

73

74

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

74

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

75

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

76

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

76

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

77

unlinkat() */

78

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

77

79

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

78

80

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

79

81

argp_state, struct argp,

91

93

argz_delete(), argz_append(),

92

94

argz_stringify(), argz_add(),

93

95

argz_count() */

96

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

97

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

144

const char *hookdir = HOOKDIR;

145

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 };

171

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: ",

190

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

216

buffer_capacity += BUFFER_SIZE;

207

217

}

208

218

return buffer_capacity;

209

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

free(new_server->ip);

244

free(new_server);

226

245

return false;

227

246

}

228

247

/* Special case of first server */

229

if (mc.current_server == NULL){

248

if(*current_server == NULL){

230

249

new_server->next = new_server;

231

250

new_server->prev = new_server;

232

mc.current_server = new_server;

233

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

251

*current_server = new_server;

234

252

} else {

235

new_server->next = mc.current_server;

236

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

253

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

254

new_server->next = *current_server;

255

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

237

256

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;

257

(*current_server)->prev = new_server;

244

258

}

245

259

return true;

246

260

}

248

262

/*

249

263

* Initialize GPGME.

250

264

*/

251

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

252

const char *tempdir){

265

__attribute__((nonnull, warn_unused_result))

266

static bool init_gpgme(const char * const seckey,

267

const char * const pubkey,

268

const char * const tempdir,

269

mandos_context *mc){

253

270

gpgme_error_t rc;

254

271

gpgme_engine_info_t engine_info;

255

272

256

273

/*

257

274

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

258

275

*/

259

bool import_key(const char *filename){

276

bool import_key(const char * const filename){

260

277

int ret;

261

278

int fd;

262

279

gpgme_data_t pgp_data;

274

291

return false;

275

292

}

276

293

277

rc = gpgme_op_import(mc.ctx, pgp_data);

294

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

278

295

if(rc != GPG_ERR_NO_ERROR){

279

296

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

280

297

gpgme_strsource(rc), gpgme_strerror(rc));

324

341

}

325

342

326

343

/* Create new GPGME "context" */

327

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

344

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

328

345

if(rc != GPG_ERR_NO_ERROR){

329

346

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

330

347

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

343

360

* Decrypt OpenPGP data.

344

361

* Returns -1 on error

345

362

*/

363

__attribute__((nonnull, warn_unused_result))

346

364

static ssize_t pgp_packet_decrypt(const char *cryptotext,

347

365

size_t crypto_size,

348

char **plaintext){

366

char **plaintext,

367

mandos_context *mc){

349

368

gpgme_data_t dh_crypto, dh_plain;

350

369

gpgme_error_t rc;

351

370

ssize_t ret;

377

396

378

397

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

379

398

data buffer */

380

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

399

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

381

400

if(rc != GPG_ERR_NO_ERROR){

382

401

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

383

402

gpgme_strsource(rc), gpgme_strerror(rc));

384

403

plaintext_length = -1;

385

404

if(debug){

386

405

gpgme_decrypt_result_t result;

387

result = gpgme_op_decrypt_result(mc.ctx);

406

result = gpgme_op_decrypt_result(mc->ctx);

388

407

if(result == NULL){

389

408

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

390

409

} else {

467

486

return plaintext_length;

468

487

}

469

488

470

static const char * safer_gnutls_strerror(int value){

489

__attribute__((warn_unused_result))

490

static const char *safer_gnutls_strerror(int value){

471

491

const char *ret = gnutls_strerror(value);

472

492

if(ret == NULL)

473

493

ret = "(unknown)";

475

495

}

476

496

477

497

/* GnuTLS log function callback */

498

__attribute__((nonnull))

478

499

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

479

500

const char* string){

480

501

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

481

502

}

482

503

504

__attribute__((nonnull, warn_unused_result))

483

505

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename){

506

const char *seckeyfilename,

507

mandos_context *mc){

485

508

int ret;

486

509

487

510

if(debug){

504

527

}

505

528

506

529

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

530

ret = gnutls_certificate_allocate_credentials(&mc->cred);

508

531

if(ret != GNUTLS_E_SUCCESS){

509

532

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

510

533

safer_gnutls_strerror(ret));

520

543

}

521

544

522

545

ret = gnutls_certificate_set_openpgp_key_file

523

(mc.cred, pubkeyfilename, seckeyfilename,

546

(mc->cred, pubkeyfilename, seckeyfilename,

524

547

GNUTLS_OPENPGP_FMT_BASE64);

525

548

if(ret != GNUTLS_E_SUCCESS){

526

549

fprintf_plus(stderr,

532

555

}

533

556

534

557

/* GnuTLS server initialization */

535

ret = gnutls_dh_params_init(&mc.dh_params);

558

ret = gnutls_dh_params_init(&mc->dh_params);

536

559

if(ret != GNUTLS_E_SUCCESS){

537

560

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

561

" initialization: %s\n",

539

562

safer_gnutls_strerror(ret));

540

563

goto globalfail;

541

564

}

542

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

565

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

543

566

if(ret != GNUTLS_E_SUCCESS){

544

567

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

545

568

safer_gnutls_strerror(ret));

546

569

goto globalfail;

547

570

}

548

571

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

572

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

550

573

551

574

return 0;

552

575

553

576

globalfail:

554

577

555

gnutls_certificate_free_credentials(mc.cred);

578

gnutls_certificate_free_credentials(mc->cred);

556

579

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

580

gnutls_dh_params_deinit(mc->dh_params);

558

581

return -1;

559

582

}

560

583

561

static int init_gnutls_session(gnutls_session_t *session){

584

__attribute__((nonnull, warn_unused_result))

585

static int init_gnutls_session(gnutls_session_t *session,

586

mandos_context *mc){

562

587

int ret;

563

588

/* GnuTLS session creation */

564

589

do {

576

601

{

577

602

const char *err;

578

603

do {

579

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

604

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

580

605

if(quit_now){

581

606

gnutls_deinit(*session);

582

607

return -1;

593

618

594

619

do {

595

620

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

621

mc->cred);

597

622

if(quit_now){

598

623

gnutls_deinit(*session);

599

624

return -1;

609

634

/* ignore client certificate if any. */

610

635

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

636

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

637

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

613

638

614

639

return 0;

615

640

}

619

644

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

620

645

621

646

/* Called when a Mandos server is found */

647

__attribute__((nonnull, warn_unused_result))

622

648

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

623

649

AvahiIfIndex if_index,

624

int af){

650

int af, mandos_context *mc){

625

651

int ret, tcp_sd = -1;

626

652

ssize_t sret;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

653

struct sockaddr_storage to;

631

654

char *buffer = NULL;

632

655

char *decrypted_buffer = NULL;

633

656

size_t buffer_length = 0;

657

680

return -1;

658

681

}

659

682

660

ret = init_gnutls_session(&session);

683

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

684

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

685

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

686

bool match = false;

687

{

688

char *interface = NULL;

689

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

690

interface))){

691

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

692

match = true;

693

break;

694

}

695

}

696

}

697

if(not match){

698

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

699

connect to the server */

700

if(debug){

701

char interface[IF_NAMESIZE];

702

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

703

perror_plus("if_indextoname");

704

} else {

705

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

706

" \"%s\"\n",

707

if_indextoname((unsigned int)if_index,

708

interface));

709

}

710

}

711

return -1;

712

}

713

}

714

715

ret = init_gnutls_session(&session, mc);

661

716

if(ret != 0){

662

717

return -1;

663

718

}

682

737

683

738

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

684

739

if(af == AF_INET6){

685

to.in6.sin6_family = (sa_family_t)af;

686

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

740

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

741

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

687

742

} else { /* IPv4 */

688

to.in.sin_family = (sa_family_t)af;

689

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

743

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

744

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

690

745

}

691

746

if(ret < 0 ){

692

747

int e = errno;

701

756

goto mandos_end;

702

757

}

703

758

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*/

759

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

760

if(IN6_IS_ADDR_LINKLOCAL

761

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

708

762

if(if_index == AVAHI_IF_UNSPEC){

709

763

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

710

764

" incomplete without a network interface\n");

712

766

goto mandos_end;

713

767

}

714

768

/* Set the network interface number as scope */

715

to.in6.sin6_scope_id = (uint32_t)if_index;

769

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

716

770

}

717

771

} else {

718

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

719

-Wconversion and

720

-Wunreachable-code */

772

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

721

773

}

722

774

723

775

if(quit_now){

740

792

}

741

793

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

742

794

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

743

const char *pcret;

744

795

if(af == AF_INET6){

745

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

746

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in6),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

747

800

} else {

748

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

749

sizeof(addrstr));

801

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

802

sizeof(struct sockaddr_in),

803

addrstr, sizeof(addrstr), NULL, 0,

804

NI_NUMERICHOST);

750

805

}

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

}

806

if(ret == EAI_SYSTEM){

807

perror_plus("getnameinfo");

808

} else if(ret != 0) {

809

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

810

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

811

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

757

812

}

758

813

}

759

814

763

818

}

764

819

765

820

if(af == AF_INET6){

766

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

821

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

822

sizeof(struct sockaddr_in6));

767

823

} else {

768

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

824

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

825

sizeof(struct sockaddr_in));

769

826

}

770

827

if(ret < 0){

771

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

828

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

772

829

int e = errno;

773

830

perror_plus("connect");

774

831

errno = e;

935

992

if(buffer_length > 0){

936

993

ssize_t decrypted_buffer_size;

937

994

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

938

&decrypted_buffer);

995

&decrypted_buffer, mc);

939

996

if(decrypted_buffer_size >= 0){

940

997

941

998

written = 0;

989

1046

return retval;

990

1047

}

991

1048

1049

__attribute__((nonnull))

992

1050

static void resolve_callback(AvahiSServiceResolver *r,

993

1051

AvahiIfIndex interface,

994

1052

AvahiProtocol proto,

1002

1060

AVAHI_GCC_UNUSED AvahiStringList *txt,

1003

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1004

1062

flags,

1005

AVAHI_GCC_UNUSED void* userdata){

1063

void *mc){

1006

1064

if(r == NULL){

1007

1065

return;

1008

1066

}

1020

1078

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

1021

1079

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

1022

1080

domain,

1023

avahi_strerror(avahi_server_errno(mc.server)));

1081

avahi_strerror(avahi_server_errno

1082

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

1024

1083

break;

1025

1084

1026

1085

case AVAHI_RESOLVER_FOUND:

1034

1093

}

1035

1094

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

1036

1095

interface,

1037

avahi_proto_to_af(proto));

1096

avahi_proto_to_af(proto),

1097

mc);

1038

1098

if(ret == 0){

1039

1099

avahi_simple_poll_quit(simple_poll);

1040

1100

} else {

1041

1101

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

1042

avahi_proto_to_af(proto))){

1102

avahi_proto_to_af(proto),

1103

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

1043

1104

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

1044

1105

" list\n", name);

1045

1106

}

1058

1119

const char *domain,

1059

1120

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1121

flags,

1061

AVAHI_GCC_UNUSED void* userdata){

1122

void *mc){

1062

1123

if(b == NULL){

1063

1124

return;

1064

1125

}

1075

1136

case AVAHI_BROWSER_FAILURE:

1076

1137

1077

1138

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

1078

avahi_strerror(avahi_server_errno(mc.server)));

1139

avahi_strerror(avahi_server_errno

1140

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

1079

1141

avahi_simple_poll_quit(simple_poll);

1080

1142

return;

1081

1143

1085

1147

the callback function is called the Avahi server will free the

1086

1148

resolver for us. */

1087

1149

1088

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

1089

name, type, domain, protocol, 0,

1090

resolve_callback, NULL) == NULL)

1150

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

1151

interface, protocol, name, type,

1152

domain, protocol, 0,

1153

resolve_callback, mc) == NULL)

1091

1154

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

1092

1155

" %s\n", name,

1093

avahi_strerror(avahi_server_errno(mc.server)));

1156

avahi_strerror(avahi_server_errno

1157

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

1094

1158

break;

1095

1159

1096

1160

case AVAHI_BROWSER_REMOVE:

1121

1185

errno = old_errno;

1122

1186

}

1123

1187

1188

__attribute__((nonnull, warn_unused_result))

1124

1189

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

1125

1190

int ret;

1126

1191

error_t ret_errno;

1145

1210

return true;

1146

1211

}

1147

1212

1213

__attribute__((nonnull, warn_unused_result))

1148

1214

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

1149

1215

1150

1216

/* Reject the loopback device */

1192

1258

* corresponds to an acceptable network device.

1193

1259

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

1194

1260

*/

1261

__attribute__((nonnull, warn_unused_result))

1195

1262

int good_interface(const struct dirent *if_entry){

1196

1263

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

1197

1264

return 0;

1215

1282

/*

1216

1283

* This function determines if a network interface is up.

1217

1284

*/

1285

__attribute__((nonnull, warn_unused_result))

1218

1286

bool interface_is_up(const char *interface){

1219

1287

struct ifreq ifr;

1220

1288

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

1231

1299

/*

1232

1300

* This function determines if a network interface is running

1233

1301

*/

1302

__attribute__((nonnull, warn_unused_result))

1234

1303

bool interface_is_running(const char *interface){

1235

1304

struct ifreq ifr;

1236

1305

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

1244

1313

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

1245

1314

}

1246

1315

1316

__attribute__((nonnull, pure, warn_unused_result))

1247

1317

int notdotentries(const struct dirent *direntry){

1248

1318

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

1249

1319

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

1256

1326

}

1257

1327

1258

1328

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

1329

__attribute__((nonnull, warn_unused_result))

1259

1330

int runnable_hook(const struct dirent *direntry){

1260

1331

int ret;

1261

1332

size_t sret;

1269

1340

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

1270

1341

"abcdefghijklmnopqrstuvwxyz"

1271

1342

"0123456789"

1272

"_-");

1343

"_.-");

1273

1344

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

1274

1345

/* Contains non-allowed characters */

1275

1346

if(debug){

1279

1350

return 0;

1280

1351

}

1281

1352

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);

1353

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

1290

1354

if(ret == -1){

1291

1355

if(debug){

1292

1356

perror_plus("Could not stat hook");

1316

1380

return 1;

1317

1381

}

1318

1382

1319

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1383

__attribute__((nonnull, warn_unused_result))

1384

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1385

mandos_context *mc){

1320

1386

int ret;

1321

1387

struct timespec now;

1322

1388

struct timespec waited_time;

1323

1389

intmax_t block_time;

1324

1390

1325

1391

while(true){

1326

if(mc.current_server == NULL){

1327

if (debug){

1392

if(mc->current_server == NULL){

1393

if(debug){

1328

1394

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

1329

1395

" No timeout!\n");

1330

1396

}

1331

1397

ret = avahi_simple_poll_iterate(s, -1);

1332

1398

} else {

1333

if (debug){

1399

if(debug){

1334

1400

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

1335

1401

" it, or wait\n");

1336

1402

}

1343

1409

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

1344

1410

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

1345

1411

waited_time.tv_sec = (now.tv_sec

1346

- mc.current_server->last_seen.tv_sec);

1412

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

1347

1413

waited_time.tv_nsec = (now.tv_nsec

1348

- mc.current_server->last_seen.tv_nsec);

1414

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

1349

1415

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

1350

1416

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

1351

1417

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

1353

1419

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

1354

1420

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

1355

1421

1356

if (debug){

1422

if(debug){

1357

1423

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

1358

1424

block_time);

1359

1425

}

1360

1426

1361

1427

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);

1428

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

1429

mc->current_server->port,

1430

mc->current_server->if_index,

1431

mc->current_server->af, mc);

1366

1432

if(ret == 0){

1367

avahi_simple_poll_quit(simple_poll);

1433

avahi_simple_poll_quit(s);

1368

1434

return 0;

1369

1435

}

1370

1436

ret = clock_gettime(CLOCK_MONOTONIC,

1371

&mc.current_server->last_seen);

1437

&mc->current_server->last_seen);

1372

1438

if(ret == -1){

1373

1439

perror_plus("clock_gettime");

1374

1440

return -1;

1375

1441

}

1376

mc.current_server = mc.current_server->next;

1442

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

1377

1443

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

1378

1444

servers, but don't block */

1379

1445

}

1381

1447

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

1382

1448

}

1383

1449

if(ret != 0){

1384

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

1450

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

1385

1451

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

1386

1452

}

1387

1453

}

1389

1455

}

1390

1456

1391

1457

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

1458

__attribute__((warn_unused_result))

1392

1459

error_t raise_privileges(void){

1393

1460

error_t old_errno = errno;

1394

1461

error_t ret_errno = 0;

1395

1462

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

1396

1463

ret_errno = errno;

1397

perror_plus("seteuid");

1398

1464

}

1399

1465

errno = old_errno;

1400

1466

return ret_errno;

1401

1467

}

1402

1468

1403

1469

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

1470

__attribute__((warn_unused_result))

1404

1471

error_t raise_privileges_permanently(void){

1405

1472

error_t old_errno = errno;

1406

1473

error_t ret_errno = raise_privileges();

1410

1477

}

1411

1478

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

1412

1479

ret_errno = errno;

1413

perror_plus("seteuid");

1414

1480

}

1415

1481

errno = old_errno;

1416

1482

return ret_errno;

1417

1483

}

1418

1484

1419

1485

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

1486

__attribute__((warn_unused_result))

1420

1487

error_t lower_privileges(void){

1421

1488

error_t old_errno = errno;

1422

1489

error_t ret_errno = 0;

1423

1490

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

1424

1491

ret_errno = errno;

1425

perror_plus("seteuid");

1426

1492

}

1427

1493

errno = old_errno;

1428

1494

return ret_errno;

1429

1495

}

1430

1496

1431

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1432

1499

error_t lower_privileges_permanently(void){

1433

1500

error_t old_errno = errno;

1434

1501

error_t ret_errno = 0;

1435

1502

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

1436

1503

ret_errno = errno;

1437

perror_plus("setuid");

1438

1504

}

1439

1505

errno = old_errno;

1440

1506

return ret_errno;

1441

1507

}

1442

1508

1443

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

1509

__attribute__((nonnull))

1510

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

1444

1511

const float delay){

1445

struct dirent **direntries;

1512

struct dirent **direntries = NULL;

1513

if(hookdir_fd == -1){

1514

hookdir_fd = open(hookdir, O_RDONLY);

1515

if(hookdir_fd == -1){

1516

if(errno == ENOENT){

1517

if(debug){

1518

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

1519

" found\n", hookdir);

1520

}

1521

} else {

1522

perror_plus("open");

1523

}

1524

return;

1525

}

1526

}

1527

#ifdef __GLIBC__

1528

#if __GLIBC_PREREQ(2, 15)

1529

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

1530

runnable_hook, alphasort);

1531

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

1532

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

1533

alphasort);

1534

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

1535

#else /* not __GLIBC__ */

1536

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

1537

alphasort);

1538

#endif /* not __GLIBC__ */

1539

if(numhooks == -1){

1540

perror_plus("scandir");

1541

return;

1542

}

1446

1543

struct dirent *direntry;

1447

1544

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");

1545

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

1546

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

1547

direntry = direntries[i];

1548

if(debug){

1549

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

1550

direntry->d_name);

1458

1551

}

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){

1552

pid_t hook_pid = fork();

1553

if(hook_pid == 0){

1554

/* Child */

1555

/* Raise privileges */

1556

errno = raise_privileges_permanently();

1557

if(errno != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1590

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

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

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

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

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

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

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

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

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

1612

if(ret == -1){

1466

1613

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

}

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1525

1618

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

}

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

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

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

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

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

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

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

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

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

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

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

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

1653

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

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

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

1659

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

1660

WTERMSIG(status));

1661

continue;

1537

1662

} 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;

1663

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

1664

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

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

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

1670

direntry->d_name);

1671

}

1672

}

1673

free(direntries);

1674

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

1675

perror_plus("close");

1676

} else {

1677

hookdir_fd = -1;

1678

}

1679

close(devnull);

1574

1680

}

1575

1681

1682

__attribute__((nonnull, warn_unused_result))

1576

1683

error_t bring_up_interface(const char *const interface,

1577

1684

const float delay){

1578

int sd = -1;

1579

1685

error_t old_errno = errno;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1686

int ret;

1582

1687

struct ifreq network;

1583

1688

unsigned int if_index = if_nametoindex(interface);

1584

1689

if(if_index == 0){

1593

1698

}

1594

1699

1595

1700

if(not interface_is_up(interface)){

1596

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

1701

error_t ret_errno = 0, ioctl_errno = 0;

1702

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

1597

1703

ret_errno = errno;

1598

1704

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

1599

1705

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

1706

errno = old_errno;

1600

1707

return ret_errno;

1601

1708

}

1602

network.ifr_flags |= IFF_UP;

1709

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

1603

1710

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1711

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

1712

if(sd == -1){

1606

1713

ret_errno = errno;

1607

1714

perror_plus("socket");

1608

1715

errno = old_errno;

1609

1716

return ret_errno;

1610

1717

}

1611

1718

1612

1719

if(quit_now){

1613

close(sd);

1720

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

1721

if(ret == -1){

1722

perror_plus("close");

1723

}

1614

1724

errno = old_errno;

1615

1725

return EINTR;

1616

1726

}

1620

1730

interface);

1621

1731

}

1622

1732

1623

/* Raise priviliges */

1624

raise_privileges();

1733

/* Raise privileges */

1734

ret_errno = raise_privileges();

1735

if(ret_errno != 0){

1736

errno = ret_errno;

1737

perror_plus("Failed to raise privileges");

1738

}

1625

1739

1626

1740

#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");

1741

int ret_linux;

1742

bool restore_loglevel = false;

1743

if(ret_errno == 0){

1744

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1745

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

1746

ret_linux = klogctl(8, NULL, 5);

1747

if(ret_linux == -1){

1748

perror_plus("klogctl");

1749

} else {

1750

restore_loglevel = true;

1751

}

1634

1752

}

1635

1753

#endif /* __linux__ */

1636

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

1637

ret_errno = errno;

1754

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

1755

ioctl_errno = errno;

1638

1756

#ifdef __linux__

1639

1757

if(restore_loglevel){

1640

1758

ret_linux = klogctl(7, NULL, 0);

1644

1762

}

1645

1763

#endif /* __linux__ */

1646

1764

1647

/* Lower privileges */

1648

lower_privileges();

1765

/* If raise_privileges() succeeded above */

1766

if(ret_errno == 0){

1767

/* Lower privileges */

1768

ret_errno = lower_privileges();

1769

if(ret_errno != 0){

1770

errno = ret_errno;

1771

perror_plus("Failed to lower privileges");

1772

}

1773

}

1649

1774

1650

1775

/* Close the socket */

1651

1776

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

1654

1779

}

1655

1780

1656

1781

if(ret_setflags == -1){

1657

errno = ret_errno;

1782

errno = ioctl_errno;

1658

1783

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1659

1784

errno = old_errno;

1660

return ret_errno;

1785

return ioctl_errno;

1661

1786

}

1662

1787

} else if(debug){

1663

1788

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

1681

1806

return 0;

1682

1807

}

1683

1808

1809

__attribute__((nonnull, warn_unused_result))

1684

1810

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1686

1811

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1689

1812

struct ifreq network;

1690

1813

unsigned int if_index = if_nametoindex(interface);

1691

1814

if(if_index == 0){

1694

1817

return ENXIO;

1695

1818

}

1696

1819

if(interface_is_up(interface)){

1820

error_t ret_errno = 0, ioctl_errno = 0;

1697

1821

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

1698

1822

ret_errno = errno;

1699

1823

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

1700

1824

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

1825

errno = old_errno;

1701

1826

return ret_errno;

1702

1827

}

1703

1828

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

1704

1829

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1830

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

1831

if(sd == -1){

1707

1832

ret_errno = errno;

1708

1833

perror_plus("socket");

1709

1834

errno = old_errno;

1715

1840

interface);

1716

1841

}

1717

1842

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();

1843

/* Raise privileges */

1844

ret_errno = raise_privileges();

1845

if(ret_errno != 0){

1846

errno = ret_errno;

1847

perror_plus("Failed to raise privileges");

1848

}

1849

1850

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

1851

ioctl_errno = errno;

1852

1853

/* If raise_privileges() succeeded above */

1854

if(ret_errno == 0){

1855

/* Lower privileges */

1856

ret_errno = lower_privileges();

1857

if(ret_errno != 0){

1858

errno = ret_errno;

1859

perror_plus("Failed to lower privileges");

1860

}

1861

}

1726

1862

1727

1863

/* Close the socket */

1728

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

1864

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

1729

1865

if(ret == -1){

1730

1866

perror_plus("close");

1731

1867

}

1732

1868

1733

1869

if(ret_setflags == -1){

1734

errno = ret_errno;

1870

errno = ioctl_errno;

1735

1871

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1736

1872

errno = old_errno;

1737

return ret_errno;

1873

return ioctl_errno;

1738

1874

}

1739

1875

} else if(debug){

1740

1876

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

1746

1882

}

1747

1883

1748

1884

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

1885

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

1886

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

1887

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

1888

.interfaces = NULL, .interfaces_size = 0 };

1749

1889

AvahiSServiceBrowser *sb = NULL;

1750

1890

error_t ret_errno;

1751

1891

int ret;

1752

1892

intmax_t tmpmax;

1753

1893

char *tmp;

1754

1894

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1757

1895

char *interfaces_to_take_down = NULL;

1758

1896

size_t interfaces_to_take_down_size = 0;

1759

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

1760

bool tempdir_created = false;

1897

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

1898

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

1899

char *tempdir = NULL;

1761

1900

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1762

1901

const char *seckey = PATHDIR "/" SECKEY;

1763

1902

const char *pubkey = PATHDIR "/" PUBKEY;

1764

1903

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1766

1904

1767

1905

bool gnutls_initialized = false;

1768

1906

bool gpgme_initialized = false;

1859

1997

connect_to = arg;

1860

1998

break;

1861

1999

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

1862

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

1863

(int)',');

2000

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

2001

arg, (int)',');

1864

2002

if(ret_errno != 0){

1865

2003

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

1866

2004

}

1946

2084

/* Work around Debian bug #633582:

1947

2085

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

1948

2086

1949

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

2087

/* Re-raise privileges */

2088

ret_errno = raise_privileges();

2089

if(ret_errno != 0){

2090

errno = ret_errno;

2091

perror_plus("Failed to raise privileges");

2092

} else {

1951

2093

struct stat st;

1952

2094

1953

2095

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

1993

2135

}

1994

2136

1995

2137

/* Lower privileges */

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2138

ret_errno = lower_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to lower privileges");

2000

2142

}

2001

2143

}

2002

2144

}

2003

2145

2004

/* Remove empty interface names */

2146

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

2005

2147

{

2006

2148

char *interface = NULL;

2007

while((interface = argz_next(interfaces, interfaces_size,

2149

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

2008

2150

interface))){

2009

if(if_nametoindex(interface) == 0){

2010

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

2151

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

2152

and if_nametoindex(interface) == 0){

2153

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

2011

2154

fprintf_plus(stderr, "Not using nonexisting interface"

2012

2155

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

2013

2156

}

2014

argz_delete(&interfaces, &interfaces_size, interface);

2157

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

2015

2158

interface = NULL;

2016

2159

}

2017

2160

}

2019

2162

2020

2163

/* Run network hooks */

2021

2164

{

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2165

if(mc.interfaces != NULL){

2166

interfaces_hooks = malloc(mc.interfaces_size);

2025

2167

if(interfaces_hooks == NULL){

2026

2168

perror_plus("malloc");

2027

2169

goto end;

2028

2170

}

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

}

2171

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

2172

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

2173

}

2174

run_network_hooks("start", interfaces_hooks != NULL ?

2175

interfaces_hooks : "", delay);

2038

2176

}

2039

2177

2040

2178

if(not debug){

2117

2255

}

2118

2256

2119

2257

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

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2258

if(mc.interfaces == NULL){

2259

struct dirent **direntries = NULL;

2122

2260

/* Look for any good interfaces */

2123

2261

ret = scandir(sys_class_net, &direntries, good_interface,

2124

2262

alphasort);

2125

2263

if(ret >= 1){

2126

2264

/* Add all found interfaces to interfaces list */

2127

2265

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2266

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

2129

2267

direntries[i]->d_name);

2130

2268

if(ret_errno != 0){

2269

errno = ret_errno;

2131

2270

perror_plus("argz_add");

2132

2271

continue;

2133

2272

}

2138

2277

}

2139

2278

free(direntries);

2140

2279

} else {

2141

free(direntries);

2280

if(ret == 0){

2281

free(direntries);

2282

}

2142

2283

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

2143

2284

exitcode = EXIT_FAILURE;

2144

2285

goto end;

2145

2286

}

2146

2287

}

2147

2288

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)){

2289

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

2290

{

2160

2291

char *interface = NULL;

2161

while((interface = argz_next(interfaces, interfaces_size,

2292

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

2162

2293

interface))){

2294

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

2295

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

2296

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

2297

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

2298

interface);

2299

interface = NULL;

2300

while((interface = argz_next(mc.interfaces,

2301

mc.interfaces_size, interface))){

2302

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

2303

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

2304

interface);

2305

interface = NULL;

2306

}

2307

}

2308

break;

2309

}

2163

2310

bool interface_was_up = interface_is_up(interface);

2164

ret = bring_up_interface(interface, delay);

2311

errno = bring_up_interface(interface, delay);

2165

2312

if(not interface_was_up){

2166

if(ret != 0){

2167

errno = ret;

2313

if(errno != 0){

2168

2314

perror_plus("Failed to bring up interface");

2169

2315

} else {

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

2316

errno = argz_add(&interfaces_to_take_down,

2317

&interfaces_to_take_down_size,

2318

interface);

2319

if(errno != 0){

2320

perror_plus("argz_add");

2321

}

2173

2322

}

2174

2323

}

2175

2324

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2179

2325

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

2180

2326

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

2181

2327

}

2182

2328

}

2183

2329

2330

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

2331

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

2332

if(debug){

2333

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

2334

mc.interfaces);

2335

}

2336

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

2337

}

2338

2184

2339

if(quit_now){

2185

2340

goto end;

2186

2341

}

2187

2342

2188

ret = init_gnutls_global(pubkey, seckey);

2343

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

2189

2344

if(ret == -1){

2190

2345

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

2191

2346

exitcode = EX_UNAVAILABLE;

2198

2353

goto end;

2199

2354

}

2200

2355

2201

if(mkdtemp(tempdir) == NULL){

2356

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

2357

tempdir = mkdtemp(run_tempdir);

2358

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

2359

if(debug){

2360

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

2361

run_tempdir, old_tempdir);

2362

}

2363

tempdir = mkdtemp(old_tempdir);

2364

}

2365

if(tempdir == NULL){

2202

2366

perror_plus("mkdtemp");

2203

2367

goto end;

2204

2368

}

2205

tempdir_created = true;

2206

2369

2207

2370

if(quit_now){

2208

2371

goto end;

2209

2372

}

2210

2373

2211

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

2374

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

2212

2375

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

2213

2376

exitcode = EX_UNAVAILABLE;

2214

2377

goto end;

2244

2407

exitcode = EX_USAGE;

2245

2408

goto end;

2246

2409

}

2247

2410

2248

2411

if(quit_now){

2249

2412

goto end;

2250

2413

}

2271

2434

}

2272

2435

2273

2436

while(not quit_now){

2274

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

2437

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

2438

&mc);

2275

2439

if(quit_now or ret == 0){

2276

2440

break;

2277

2441

}

2279

2443

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

2280

2444

(int)retry_interval);

2281

2445

}

2282

sleep((int)retry_interval);

2446

sleep((unsigned int)retry_interval);

2283

2447

}

2284

2448

2285

if (not quit_now){

2449

if(not quit_now){

2286

2450

exitcode = EXIT_SUCCESS;

2287

2451

}

2288

2452

2325

2489

/* Create the Avahi service browser */

2326

2490

sb = avahi_s_service_browser_new(mc.server, if_index,

2327

2491

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2328

NULL, 0, browse_callback, NULL);

2492

NULL, 0, browse_callback,

2493

(void *)&mc);

2329

2494

if(sb == NULL){

2330

2495

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

2331

2496

avahi_strerror(avahi_server_errno(mc.server)));

2342

2507

if(debug){

2343

2508

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

2344

2509

}

2345

2510

2346

2511

ret = avahi_loop_with_timeout(simple_poll,

2347

(int)(retry_interval * 1000));

2512

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

2348

2513

if(debug){

2349

2514

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

2350

2515

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

2357

2522

}

2358

2523

2359

2524

/* Cleanup things */

2525

free(mc.interfaces);

2526

2360

2527

if(sb != NULL)

2361

2528

avahi_s_service_browser_free(sb);

2362

2529

2387

2554

}

2388

2555

}

2389

2556

2390

/* Re-raise priviliges */

2557

/* Re-raise privileges */

2391

2558

{

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();

2559

ret_errno = raise_privileges();

2560

if(ret_errno != 0){

2561

errno = ret_errno;

2562

perror_plus("Failed to raise privileges");

2563

} else {

2564

2565

/* Run network hooks */

2566

run_network_hooks("stop", interfaces_hooks != NULL ?

2567

interfaces_hooks : "", delay);

2568

2569

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

2570

{

2571

char *interface = NULL;

2572

while((interface=argz_next(interfaces_to_take_down,

2573

interfaces_to_take_down_size,

2574

interface))){

2575

ret_errno = take_down_interface(interface);

2576

if(ret_errno != 0){

2577

errno = ret_errno;

2578

perror_plus("Failed to take down interface");

2579

}

2580

}

2581

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

2582

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

2583

" down\n");

2584

}

2585

}

2586

}

2587

2588

ret_errno = lower_privileges_permanently();

2589

if(ret_errno != 0){

2590

errno = ret_errno;

2591

perror_plus("Failed to lower privileges permanently");

2592

}

2417

2593

}

2418

2594

2419

2595

free(interfaces_to_take_down);

2420

2596

free(interfaces_hooks);

2421

2597

2422

2598

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

2423

if(tempdir_created){

2599

if(tempdir != NULL){

2424

2600

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);

2601

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

2602

O_NOFOLLOW));

2603

if(tempdir_fd == -1){

2604

perror_plus("open");

2605

} else {

2606

#ifdef __GLIBC__

2607

#if __GLIBC_PREREQ(2, 15)

2608

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

2609

notdotentries, alphasort);

2610

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

2611

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

2612

alphasort);

2613

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

2614

#else /* not __GLIBC__ */

2615

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

2616

alphasort);

2617

#endif /* not __GLIBC__ */

2618

if(numentries >= 0){

2619

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

2620

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

2621

if(ret == -1){

2622

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

2623

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

2624

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

2625

}

2626

}

2627

2628

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

2629

free(direntries);

2630

if(numentries == -1){

2631

perror_plus("scandir");

2632

}

2633

ret = rmdir(tempdir);

2634

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

2635

perror_plus("rmdir");

2636

}

2444

2637

}

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");

2638

TEMP_FAILURE_RETRY(close(tempdir_fd));

2455

2639

}

2456

2640

}

2457

2641