/mandos/trunk : revision 601

9

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

10

*

11

* Everything else is

12

13

12

13

14

*

15

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

16

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

32

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

33

#ifndef _LARGEFILE_SOURCE

34

#define _LARGEFILE_SOURCE

35

#endif /* not _LARGEFILE_SOURCE */

35

#endif

36

#ifndef _FILE_OFFSET_BITS

37

#define _FILE_OFFSET_BITS 64

38

#endif /* not _FILE_OFFSET_BITS */

38

#endif

39

40

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

41

42

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

43

stdout, ferror() */

43

stdout, ferror(), remove() */

44

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

45

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

46

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

55

opendir(), DIR */

56

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

57

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

58

inet_pton(), connect(),

59

getnameinfo() */

60

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

58

inet_pton(), connect() */

59

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

61

60

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

62

61

*/

63

62

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

73

72

*/

74

73

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

75

74

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

76

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

77

unlinkat() */

78

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

75

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

76

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

79

77

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

80

78

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

81

79

argp_state, struct argp,

93

91

argz_delete(), argz_append(),

94

92

argz_stringify(), argz_add(),

95

93

argz_count() */

96

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

97

EAI_SYSTEM, gai_strerror() */

98

94

99

95

#ifdef __linux__

100

96

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

142

138

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

143

139

char *connect_to = NULL;

144

140

const char *hookdir = HOOKDIR;

145

int hookdir_fd = -1;

146

141

uid_t uid = 65534;

147

142

gid_t gid = 65534;

148

143

166

161

const char *priority;

167

162

gpgme_ctx_t ctx;

168

163

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

164

} mandos_context;

172

165

173

166

/* global so signal handler can reach it*/

174

167

AvahiSimplePoll *simple_poll;

168

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

169

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

170

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

175

171

176

172

sig_atomic_t quit_now = 0;

177

173

int signal_received = 0;

185

181

perror(print_text);

186

182

}

187

183

188

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

184

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

189

185

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

190

186

va_list ap;

191

187

va_start (ap, format);

192

188

193

189

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

194

190

program_invocation_short_name));

195

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

191

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

196

192

}

197

193

198

194

/*

200

196

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

201

197

* "buffer_length" is how much is already used.

202

198

*/

203

__attribute__((nonnull, warn_unused_result))

204

199

size_t incbuffer(char **buffer, size_t buffer_length,

205

200

size_t buffer_capacity){

206

201

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

202

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

203

if(buffer == NULL){

213

204

return 0;

214

205

}

215

*buffer = new_buf;

216

206

buffer_capacity += BUFFER_SIZE;

217

207

}

218

208

return buffer_capacity;

219

209

}

220

210

221

211

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

222

__attribute__((nonnull, warn_unused_result))

223

212

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

224

int af, server **current_server){

213

int af){

225

214

int ret;

226

215

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

227

216

if(new_server == NULL){

236

225

perror_plus("strdup");

237

226

return false;

238

227

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

244

228

/* Special case of first server */

245

if(*current_server == NULL){

229

if (mc.current_server == NULL){

246

230

new_server->next = new_server;

247

231

new_server->prev = new_server;

248

*current_server = new_server;

232

mc.current_server = new_server;

233

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

249

234

} else {

250

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

251

new_server->next = *current_server;

252

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

235

new_server->next = mc.current_server;

236

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

253

237

new_server->prev->next = new_server;

254

(*current_server)->prev = 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;

255

244

}

256

245

return true;

257

246

}

259

248

/*

260

249

* Initialize GPGME.

261

250

*/

262

__attribute__((nonnull, warn_unused_result))

263

static bool init_gpgme(const char * const seckey,

264

const char * const pubkey,

265

const char * const tempdir,

266

mandos_context *mc){

251

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

252

const char *tempdir){

267

253

gpgme_error_t rc;

268

254

gpgme_engine_info_t engine_info;

269

255

270

256

/*

271

257

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

272

258

*/

273

bool import_key(const char * const filename){

259

bool import_key(const char *filename){

274

260

int ret;

275

261

int fd;

276

262

gpgme_data_t pgp_data;

288

274

return false;

289

275

}

290

276

291

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

277

rc = gpgme_op_import(mc.ctx, pgp_data);

292

278

if(rc != GPG_ERR_NO_ERROR){

293

279

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

294

280

gpgme_strsource(rc), gpgme_strerror(rc));

338

324

}

339

325

340

326

/* Create new GPGME "context" */

341

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

327

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

342

328

if(rc != GPG_ERR_NO_ERROR){

343

329

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

344

330

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

357

343

* Decrypt OpenPGP data.

358

344

* Returns -1 on error

359

345

*/

360

__attribute__((nonnull, warn_unused_result))

361

346

static ssize_t pgp_packet_decrypt(const char *cryptotext,

362

347

size_t crypto_size,

363

char **plaintext,

364

mandos_context *mc){

348

char **plaintext){

365

349

gpgme_data_t dh_crypto, dh_plain;

366

350

gpgme_error_t rc;

367

351

ssize_t ret;

393

377

394

378

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

395

379

data buffer */

396

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

380

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

397

381

if(rc != GPG_ERR_NO_ERROR){

398

382

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

399

383

gpgme_strsource(rc), gpgme_strerror(rc));

400

384

plaintext_length = -1;

401

385

if(debug){

402

386

gpgme_decrypt_result_t result;

403

result = gpgme_op_decrypt_result(mc->ctx);

387

result = gpgme_op_decrypt_result(mc.ctx);

404

388

if(result == NULL){

405

389

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

406

390

} else {

483

467

return plaintext_length;

484

468

}

485

469

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

488

471

const char *ret = gnutls_strerror(value);

489

472

if(ret == NULL)

490

473

ret = "(unknown)";

492

475

}

493

476

494

477

/* GnuTLS log function callback */

495

__attribute__((nonnull))

496

478

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

497

479

const char* string){

498

480

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

499

481

}

500

482

501

__attribute__((nonnull, warn_unused_result))

502

483

static int init_gnutls_global(const char *pubkeyfilename,

503

const char *seckeyfilename,

504

mandos_context *mc){

484

const char *seckeyfilename){

505

485

int ret;

506

486

507

487

if(debug){

524

504

}

525

505

526

506

/* OpenPGP credentials */

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

528

508

if(ret != GNUTLS_E_SUCCESS){

529

509

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

530

510

safer_gnutls_strerror(ret));

540

520

}

541

521

542

522

ret = gnutls_certificate_set_openpgp_key_file

543

(mc->cred, pubkeyfilename, seckeyfilename,

523

(mc.cred, pubkeyfilename, seckeyfilename,

544

524

GNUTLS_OPENPGP_FMT_BASE64);

545

525

if(ret != GNUTLS_E_SUCCESS){

546

526

fprintf_plus(stderr,

552

532

}

553

533

554

534

/* GnuTLS server initialization */

555

ret = gnutls_dh_params_init(&mc->dh_params);

535

ret = gnutls_dh_params_init(&mc.dh_params);

556

536

if(ret != GNUTLS_E_SUCCESS){

557

537

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

558

538

" initialization: %s\n",

559

539

safer_gnutls_strerror(ret));

560

540

goto globalfail;

561

541

}

562

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

542

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

563

543

if(ret != GNUTLS_E_SUCCESS){

564

544

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

565

545

safer_gnutls_strerror(ret));

566

546

goto globalfail;

567

547

}

568

548

569

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

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

570

550

571

551

return 0;

572

552

573

553

globalfail:

574

554

575

gnutls_certificate_free_credentials(mc->cred);

555

gnutls_certificate_free_credentials(mc.cred);

576

556

gnutls_global_deinit();

577

gnutls_dh_params_deinit(mc->dh_params);

557

gnutls_dh_params_deinit(mc.dh_params);

578

558

return -1;

579

559

}

580

560

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

561

static int init_gnutls_session(gnutls_session_t *session){

584

562

int ret;

585

563

/* GnuTLS session creation */

586

564

do {

598

576

{

599

577

const char *err;

600

578

do {

601

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

579

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

602

580

if(quit_now){

603

581

gnutls_deinit(*session);

604

582

return -1;

615

593

616

594

do {

617

595

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

618

mc->cred);

596

mc.cred);

619

597

if(quit_now){

620

598

gnutls_deinit(*session);

621

599

return -1;

631

609

/* ignore client certificate if any. */

632

610

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

633

611

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

635

613

636

614

return 0;

637

615

}

641

619

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

642

620

643

621

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

645

622

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

646

623

AvahiIfIndex if_index,

647

int af, mandos_context *mc){

624

int af){

648

625

int ret, tcp_sd = -1;

649

626

ssize_t sret;

650

struct sockaddr_storage to;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

651

631

char *buffer = NULL;

652

632

char *decrypted_buffer = NULL;

653

633

size_t buffer_length = 0;

677

657

return -1;

678

658

}

679

659

680

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

681

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

682

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

683

bool match = false;

684

{

685

char *interface = NULL;

686

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

687

interface))){

688

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

689

match = true;

690

break;

691

}

692

}

693

}

694

if(not match){

695

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

696

connect to the server */

697

if(debug){

698

char interface[IF_NAMESIZE];

699

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

700

perror_plus("if_indextoname");

701

} else {

702

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

703

" \"%s\"\n",

704

if_indextoname((unsigned int)if_index,

705

interface));

706

}

707

}

708

return -1;

709

}

710

}

711

712

ret = init_gnutls_session(&session, mc);

660

ret = init_gnutls_session(&session);

713

661

if(ret != 0){

714

662

return -1;

715

663

}

734

682

735

683

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

736

684

if(af == AF_INET6){

737

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

738

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

685

to.in6.sin6_family = (sa_family_t)af;

686

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

739

687

} else { /* IPv4 */

740

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

741

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

688

to.in.sin_family = (sa_family_t)af;

689

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

742

690

}

743

691

if(ret < 0 ){

744

692

int e = errno;

753

701

goto mandos_end;

754

702

}

755

703

if(af == AF_INET6){

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

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

708

if(if_index == AVAHI_IF_UNSPEC){

760

709

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

761

710

" incomplete without a network interface\n");

763

712

goto mandos_end;

764

713

}

765

714

/* Set the network interface number as scope */

766

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

715

to.in6.sin6_scope_id = (uint32_t)if_index;

767

716

}

768

717

} else {

769

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

718

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

719

-Wconversion and

720

-Wunreachable-code */

770

721

}

771

722

772

723

if(quit_now){

789

740

}

790

741

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

791

742

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

743

const char *pcret;

792

744

if(af == AF_INET6){

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

745

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

746

sizeof(addrstr));

797

747

} else {

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

748

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

749

sizeof(addrstr));

802

750

}

803

if(ret == EAI_SYSTEM){

804

perror_plus("getnameinfo");

805

} else if(ret != 0) {

806

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

807

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

808

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

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

}

809

757

}

810

758

}

811

759

815

763

}

816

764

817

765

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

766

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

820

767

} else {

821

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

822

sizeof(struct sockaddr_in));

768

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

823

769

}

824

770

if(ret < 0){

825

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

771

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

826

772

int e = errno;

827

773

perror_plus("connect");

828

774

errno = e;

989

935

if(buffer_length > 0){

990

936

ssize_t decrypted_buffer_size;

991

937

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

992

&decrypted_buffer, mc);

938

&decrypted_buffer);

993

939

if(decrypted_buffer_size >= 0){

994

940

995

941

written = 0;

1043

989

return retval;

1044

990

}

1045

991

1046

__attribute__((nonnull))

1047

992

static void resolve_callback(AvahiSServiceResolver *r,

1048

993

AvahiIfIndex interface,

1049

994

AvahiProtocol proto,

1057

1002

AVAHI_GCC_UNUSED AvahiStringList *txt,

1058

1003

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1059

1004

flags,

1060

void *mc){

1005

AVAHI_GCC_UNUSED void* userdata){

1061

1006

if(r == NULL){

1062

1007

return;

1063

1008

}

1075

1020

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

1076

1021

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

1077

1022

domain,

1078

avahi_strerror(avahi_server_errno

1079

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

1023

avahi_strerror(avahi_server_errno(mc.server)));

1080

1024

break;

1081

1025

1082

1026

case AVAHI_RESOLVER_FOUND:

1090

1034

}

1091

1035

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

1092

1036

interface,

1093

avahi_proto_to_af(proto),

1094

mc);

1037

avahi_proto_to_af(proto));

1095

1038

if(ret == 0){

1096

1039

avahi_simple_poll_quit(simple_poll);

1097

1040

} else {

1098

1041

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

1099

avahi_proto_to_af(proto),

1100

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

1042

avahi_proto_to_af(proto))){

1101

1043

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

1102

1044

" list\n", name);

1103

1045

}

1116

1058

const char *domain,

1117

1059

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1118

1060

flags,

1119

void *mc){

1061

AVAHI_GCC_UNUSED void* userdata){

1120

1062

if(b == NULL){

1121

1063

return;

1122

1064

}

1133

1075

case AVAHI_BROWSER_FAILURE:

1134

1076

1135

1077

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

1136

avahi_strerror(avahi_server_errno

1137

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

1078

avahi_strerror(avahi_server_errno(mc.server)));

1138

1079

avahi_simple_poll_quit(simple_poll);

1139

1080

return;

1140

1081

1144

1085

the callback function is called the Avahi server will free the

1145

1086

resolver for us. */

1146

1087

1147

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

1148

interface, protocol, name, type,

1149

domain, protocol, 0,

1150

resolve_callback, mc) == NULL)

1088

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

1089

name, type, domain, protocol, 0,

1090

resolve_callback, NULL) == NULL)

1151

1091

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

1152

1092

" %s\n", name,

1153

avahi_strerror(avahi_server_errno

1154

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

1093

avahi_strerror(avahi_server_errno(mc.server)));

1155

1094

break;

1156

1095

1157

1096

case AVAHI_BROWSER_REMOVE:

1182

1121

errno = old_errno;

1183

1122

}

1184

1123

1185

__attribute__((nonnull, warn_unused_result))

1186

1124

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

1187

1125

int ret;

1188

1126

error_t ret_errno;

1207

1145

return true;

1208

1146

}

1209

1147

1210

__attribute__((nonnull, warn_unused_result))

1211

1148

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

1212

1149

1213

1150

/* Reject the loopback device */

1255

1192

* corresponds to an acceptable network device.

1256

1193

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

1257

1194

*/

1258

__attribute__((nonnull, warn_unused_result))

1259

1195

int good_interface(const struct dirent *if_entry){

1260

1196

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

1261

1197

return 0;

1279

1215

/*

1280

1216

* This function determines if a network interface is up.

1281

1217

*/

1282

__attribute__((nonnull, warn_unused_result))

1283

1218

bool interface_is_up(const char *interface){

1284

1219

struct ifreq ifr;

1285

1220

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

1296

1231

/*

1297

1232

* This function determines if a network interface is running

1298

1233

*/

1299

__attribute__((nonnull, warn_unused_result))

1300

1234

bool interface_is_running(const char *interface){

1301

1235

struct ifreq ifr;

1302

1236

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

1310

1244

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

1311

1245

}

1312

1246

1313

__attribute__((nonnull, pure, warn_unused_result))

1314

1247

int notdotentries(const struct dirent *direntry){

1315

1248

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

1316

1249

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

1323

1256

}

1324

1257

1325

1258

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

1326

__attribute__((nonnull, warn_unused_result))

1327

1259

int runnable_hook(const struct dirent *direntry){

1328

1260

int ret;

1329

1261

size_t sret;

1337

1269

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

1338

1270

"abcdefghijklmnopqrstuvwxyz"

1339

1271

"0123456789"

1340

"_.-");

1272

"_-");

1341

1273

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

1342

1274

/* Contains non-allowed characters */

1343

1275

if(debug){

1347

1279

return 0;

1348

1280

}

1349

1281

1350

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

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);

1351

1290

if(ret == -1){

1352

1291

if(debug){

1353

1292

perror_plus("Could not stat hook");

1377

1316

return 1;

1378

1317

}

1379

1318

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1319

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1383

1320

int ret;

1384

1321

struct timespec now;

1385

1322

struct timespec waited_time;

1386

1323

intmax_t block_time;

1387

1324

1388

1325

while(true){

1389

if(mc->current_server == NULL){

1390

if(debug){

1326

if(mc.current_server == NULL){

1327

if (debug){

1391

1328

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

1392

1329

" No timeout!\n");

1393

1330

}

1394

1331

ret = avahi_simple_poll_iterate(s, -1);

1395

1332

} else {

1396

if(debug){

1333

if (debug){

1397

1334

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

1398

1335

" it, or wait\n");

1399

1336

}

1406

1343

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

1407

1344

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

1408

1345

waited_time.tv_sec = (now.tv_sec

1409

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

1346

- mc.current_server->last_seen.tv_sec);

1410

1347

waited_time.tv_nsec = (now.tv_nsec

1411

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

1348

- mc.current_server->last_seen.tv_nsec);

1412

1349

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

1413

1350

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

1414

1351

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

1416

1353

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

1417

1354

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

1418

1355

1419

if(debug){

1356

if (debug){

1420

1357

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

1421

1358

block_time);

1422

1359

}

1423

1360

1424

1361

if(block_time <= 0){

1425

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

1426

mc->current_server->port,

1427

mc->current_server->if_index,

1428

mc->current_server->af, mc);

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);

1429

1366

if(ret == 0){

1430

avahi_simple_poll_quit(s);

1367

avahi_simple_poll_quit(simple_poll);

1431

1368

return 0;

1432

1369

}

1433

1370

ret = clock_gettime(CLOCK_MONOTONIC,

1434

&mc->current_server->last_seen);

1371

&mc.current_server->last_seen);

1435

1372

if(ret == -1){

1436

1373

perror_plus("clock_gettime");

1437

1374

return -1;

1438

1375

}

1439

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

1376

mc.current_server = mc.current_server->next;

1440

1377

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

1441

1378

servers, but don't block */

1442

1379

}

1444

1381

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

1445

1382

}

1446

1383

if(ret != 0){

1447

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

1384

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

1448

1385

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

1449

1386

}

1450

1387

}

1452

1389

}

1453

1390

1454

1391

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

1455

__attribute__((warn_unused_result))

1456

1392

error_t raise_privileges(void){

1457

1393

error_t old_errno = errno;

1458

1394

error_t ret_errno = 0;

1459

1395

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

1460

1396

ret_errno = errno;

1397

perror_plus("seteuid");

1461

1398

}

1462

1399

errno = old_errno;

1463

1400

return ret_errno;

1464

1401

}

1465

1402

1466

1403

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

1467

__attribute__((warn_unused_result))

1468

1404

error_t raise_privileges_permanently(void){

1469

1405

error_t old_errno = errno;

1470

1406

error_t ret_errno = raise_privileges();

1474

1410

}

1475

1411

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

1476

1412

ret_errno = errno;

1413

perror_plus("seteuid");

1477

1414

}

1478

1415

errno = old_errno;

1479

1416

return ret_errno;

1480

1417

}

1481

1418

1482

1419

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

1483

__attribute__((warn_unused_result))

1484

1420

error_t lower_privileges(void){

1485

1421

error_t old_errno = errno;

1486

1422

error_t ret_errno = 0;

1487

1423

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

1488

1424

ret_errno = errno;

1425

perror_plus("seteuid");

1489

1426

}

1490

1427

errno = old_errno;

1491

1428

return ret_errno;

1492

1429

}

1493

1430

1494

1431

/* Lower privileges permanently */

1495

__attribute__((warn_unused_result))

1496

1432

error_t lower_privileges_permanently(void){

1497

1433

error_t old_errno = errno;

1498

1434

error_t ret_errno = 0;

1499

1435

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

1500

1436

ret_errno = errno;

1437

perror_plus("setuid");

1501

1438

}

1502

1439

errno = old_errno;

1503

1440

return ret_errno;

1504

1441

}

1505

1442

1506

__attribute__((nonnull))

1507

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

1443

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

1508

1444

const float delay){

1509

struct dirent **direntries = NULL;

1510

if(hookdir_fd == -1){

1511

hookdir_fd = open(hookdir, O_RDONLY);

1512

if(hookdir_fd == -1){

1513

if(errno == ENOENT){

1514

if(debug){

1515

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

1516

" found\n", hookdir);

1517

}

1518

} else {

1519

perror_plus("open");

1520

}

1521

return;

1522

}

1523

}

1524

#ifdef __GLIBC__

1525

#if __GLIBC_PREREQ(2, 15)

1526

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

1527

runnable_hook, alphasort);

1528

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

1529

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

1530

alphasort);

1531

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

1532

#else /* not __GLIBC__ */

1533

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

1534

alphasort);

1535

#endif /* not __GLIBC__ */

1445

struct dirent **direntries;

1446

struct dirent *direntry;

1447

int ret;

1448

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

1449

alphasort);

1536

1450

if(numhooks == -1){

1537

perror_plus("scandir");

1538

return;

1539

}

1540

struct dirent *direntry;

1541

int ret;

1542

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

1543

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

1544

direntry = direntries[i];

1545

if(debug){

1546

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

1547

direntry->d_name);

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");

1548

1458

}

1549

pid_t hook_pid = fork();

1550

if(hook_pid == 0){

1551

/* Child */

1552

/* Raise privileges */

1553

errno = raise_privileges_permanently();

1554

if(errno != 0){

1555

perror_plus("Failed to raise privileges");

1556

_exit(EX_NOPERM);

1557

}

1558

/* Set group */

1559

errno = 0;

1560

ret = setgid(0);

1561

if(ret == -1){

1562

perror_plus("setgid");

1563

_exit(EX_NOPERM);

1564

}

1565

/* Reset supplementary groups */

1566

errno = 0;

1567

ret = setgroups(0, NULL);

1568

if(ret == -1){

1569

perror_plus("setgroups");

1570

_exit(EX_NOPERM);

1571

}

1572

ret = dup2(devnull, STDIN_FILENO);

1573

if(ret == -1){

1574

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

1575

_exit(EX_OSERR);

1576

}

1577

ret = close(devnull);

1578

if(ret == -1){

1579

perror_plus("close");

1580

_exit(EX_OSERR);

1581

}

1582

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1583

if(ret == -1){

1584

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

1585

_exit(EX_OSERR);

1586

}

1587

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

1588

if(ret == -1){

1589

perror_plus("setenv");

1590

_exit(EX_OSERR);

1591

}

1592

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

1593

if(ret == -1){

1594

perror_plus("setenv");

1595

_exit(EX_OSERR);

1596

}

1597

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

1598

if(ret == -1){

1599

perror_plus("setenv");

1600

_exit(EX_OSERR);

1601

}

1602

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

1603

if(ret == -1){

1604

perror_plus("setenv");

1605

_exit(EX_OSERR);

1606

}

1607

char *delaystring;

1608

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

1609

if(ret == -1){

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){

1610

1466

perror_plus("asprintf");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

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

}

1615

1525

free(delaystring);

1616

perror_plus("setenv");

1617

_exit(EX_OSERR);

1618

}

1619

free(delaystring);

1620

if(connect_to != NULL){

1621

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

1622

if(ret == -1){

1623

perror_plus("setenv");

1624

_exit(EX_OSERR);

1625

}

1626

}

1627

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

1628

if(hook_fd == -1){

1629

perror_plus("openat");

1630

_exit(EXIT_FAILURE);

1631

}

1632

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

1633

perror_plus("close");

1634

_exit(EXIT_FAILURE);

1635

}

1636

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

1637

environ) == -1){

1638

perror_plus("fexecve");

1639

_exit(EXIT_FAILURE);

1640

}

1641

} else {

1642

int status;

1643

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

1644

perror_plus("waitpid");

1645

continue;

1646

}

1647

if(WIFEXITED(status)){

1648

if(WEXITSTATUS(status) != 0){

1649

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

1650

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

1651

WEXITSTATUS(status));

1652

continue;

1653

}

1654

} else if(WIFSIGNALED(status)){

1655

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

1656

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

1657

WTERMSIG(status));

1658

continue;

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

}

1659

1537

} else {

1660

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

1661

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

1662

continue;

1663

}

1664

}

1665

if(debug){

1666

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

1667

direntry->d_name);

1668

}

1669

}

1670

free(direntries);

1671

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

1672

perror_plus("close");

1673

} else {

1674

hookdir_fd = -1;

1675

}

1676

close(devnull);

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;

1677

1574

}

1678

1575

1679

__attribute__((nonnull, warn_unused_result))

1680

1576

error_t bring_up_interface(const char *const interface,

1681

1577

const float delay){

1578

int sd = -1;

1682

1579

error_t old_errno = errno;

1683

int ret;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1684

1582

struct ifreq network;

1685

1583

unsigned int if_index = if_nametoindex(interface);

1686

1584

if(if_index == 0){

1695

1593

}

1696

1594

1697

1595

if(not interface_is_up(interface)){

1698

error_t ret_errno = 0, ioctl_errno = 0;

1699

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

1596

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

1700

1597

ret_errno = errno;

1701

1598

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

1702

1599

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

1703

errno = old_errno;

1704

1600

return ret_errno;

1705

1601

}

1706

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

1602

network.ifr_flags |= IFF_UP;

1707

1603

1708

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

1709

if(sd == -1){

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1710

1606

ret_errno = errno;

1711

1607

perror_plus("socket");

1712

1608

errno = old_errno;

1713

1609

return ret_errno;

1714

1610

}

1715

1611

1716

1612

if(quit_now){

1717

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

1718

if(ret == -1){

1719

perror_plus("close");

1720

}

1613

close(sd);

1721

1614

errno = old_errno;

1722

1615

return EINTR;

1723

1616

}

1727

1620

interface);

1728

1621

}

1729

1622

1730

/* Raise privileges */

1731

ret_errno = raise_privileges();

1732

if(ret_errno != 0){

1733

errno = ret_errno;

1734

perror_plus("Failed to raise privileges");

1735

}

1623

/* Raise priviliges */

1624

raise_privileges();

1736

1625

1737

1626

#ifdef __linux__

1738

int ret_linux;

1739

bool restore_loglevel = false;

1740

if(ret_errno == 0){

1741

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1742

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

1743

ret_linux = klogctl(8, NULL, 5);

1744

if(ret_linux == -1){

1745

perror_plus("klogctl");

1746

} else {

1747

restore_loglevel = true;

1748

}

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");

1749

1634

}

1750

1635

#endif /* __linux__ */

1751

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

1752

ioctl_errno = errno;

1636

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

1637

ret_errno = errno;

1753

1638

#ifdef __linux__

1754

1639

if(restore_loglevel){

1755

1640

ret_linux = klogctl(7, NULL, 0);

1759

1644

}

1760

1645

#endif /* __linux__ */

1761

1646

1762

/* If raise_privileges() succeeded above */

1763

if(ret_errno == 0){

1764

/* Lower privileges */

1765

ret_errno = lower_privileges();

1766

if(ret_errno != 0){

1767

errno = ret_errno;

1768

perror_plus("Failed to lower privileges");

1769

}

1770

}

1647

/* Lower privileges */

1648

lower_privileges();

1771

1649

1772

1650

/* Close the socket */

1773

1651

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

1776

1654

}

1777

1655

1778

1656

if(ret_setflags == -1){

1779

errno = ioctl_errno;

1657

errno = ret_errno;

1780

1658

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1781

1659

errno = old_errno;

1782

return ioctl_errno;

1660

return ret_errno;

1783

1661

}

1784

1662

} else if(debug){

1785

1663

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

1803

1681

return 0;

1804

1682

}

1805

1683

1806

__attribute__((nonnull, warn_unused_result))

1807

1684

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1808

1686

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1809

1689

struct ifreq network;

1810

1690

unsigned int if_index = if_nametoindex(interface);

1811

1691

if(if_index == 0){

1814

1694

return ENXIO;

1815

1695

}

1816

1696

if(interface_is_up(interface)){

1817

error_t ret_errno = 0, ioctl_errno = 0;

1818

1697

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

1819

1698

ret_errno = errno;

1820

1699

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

1821

1700

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

1822

errno = old_errno;

1823

1701

return ret_errno;

1824

1702

}

1825

1703

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

1826

1704

1827

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

1828

if(sd == -1){

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1829

1707

ret_errno = errno;

1830

1708

perror_plus("socket");

1831

1709

errno = old_errno;

1837

1715

interface);

1838

1716

}

1839

1717

1840

/* Raise privileges */

1841

ret_errno = raise_privileges();

1842

if(ret_errno != 0){

1843

errno = ret_errno;

1844

perror_plus("Failed to raise privileges");

1845

}

1846

1847

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

1848

ioctl_errno = errno;

1849

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

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();

1859

1726

1860

1727

/* Close the socket */

1861

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

1728

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

1862

1729

if(ret == -1){

1863

1730

perror_plus("close");

1864

1731

}

1865

1732

1866

1733

if(ret_setflags == -1){

1867

errno = ioctl_errno;

1734

errno = ret_errno;

1868

1735

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1869

1736

errno = old_errno;

1870

return ioctl_errno;

1737

return ret_errno;

1871

1738

}

1872

1739

} else if(debug){

1873

1740

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

1879

1746

}

1880

1747

1881

1748

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

1882

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

1883

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

1884

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

1885

.interfaces = NULL, .interfaces_size = 0 };

1886

1749

AvahiSServiceBrowser *sb = NULL;

1887

1750

error_t ret_errno;

1888

1751

int ret;

1889

1752

intmax_t tmpmax;

1890

1753

char *tmp;

1891

1754

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1892

1757

char *interfaces_to_take_down = NULL;

1893

1758

size_t interfaces_to_take_down_size = 0;

1894

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

1895

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

1896

char *tempdir = NULL;

1759

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

1760

bool tempdir_created = false;

1897

1761

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1898

1762

const char *seckey = PATHDIR "/" SECKEY;

1899

1763

const char *pubkey = PATHDIR "/" PUBKEY;

1900

1764

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1901

1766

1902

1767

bool gnutls_initialized = false;

1903

1768

bool gpgme_initialized = false;

1994

1859

connect_to = arg;

1995

1860

break;

1996

1861

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

1997

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

1998

arg, (int)',');

1862

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

1863

(int)',');

1999

1864

if(ret_errno != 0){

2000

1865

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

2001

1866

}

2081

1946

/* Work around Debian bug #633582:

2082

1947

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

2083

1948

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

2089

} else {

1949

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

2090

1951

struct stat st;

2091

1952

2092

1953

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

2132

1993

}

2133

1994

2134

1995

/* Lower privileges */

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2139

2000

}

2140

2001

}

2141

2002

}

2142

2003

2143

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

2004

/* Remove empty interface names */

2144

2005

{

2145

2006

char *interface = NULL;

2146

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

2007

while((interface = argz_next(interfaces, interfaces_size,

2147

2008

interface))){

2148

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

2149

and if_nametoindex(interface) == 0){

2150

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

2009

if(if_nametoindex(interface) == 0){

2010

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

2151

2011

fprintf_plus(stderr, "Not using nonexisting interface"

2152

2012

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

2153

2013

}

2154

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

2014

argz_delete(&interfaces, &interfaces_size, interface);

2155

2015

interface = NULL;

2156

2016

}

2157

2017

}

2159

2019

2160

2020

/* Run network hooks */

2161

2021

{

2162

if(mc.interfaces != NULL){

2163

interfaces_hooks = malloc(mc.interfaces_size);

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2164

2025

if(interfaces_hooks == NULL){

2165

2026

perror_plus("malloc");

2166

2027

goto end;

2167

2028

}

2168

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

2169

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

2170

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

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

}

2173

2038

}

2174

2039

2175

2040

if(not debug){

2252

2117

}

2253

2118

2254

2119

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

2255

if(mc.interfaces == NULL){

2256

struct dirent **direntries = NULL;

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2257

2122

/* Look for any good interfaces */

2258

2123

ret = scandir(sys_class_net, &direntries, good_interface,

2259

2124

alphasort);

2260

2125

if(ret >= 1){

2261

2126

/* Add all found interfaces to interfaces list */

2262

2127

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

2263

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2264

2129

direntries[i]->d_name);

2265

2130

if(ret_errno != 0){

2266

errno = ret_errno;

2267

2131

perror_plus("argz_add");

2268

2132

continue;

2269

2133

}

2274

2138

}

2275

2139

free(direntries);

2276

2140

} else {

2277

if(ret == 0){

2278

free(direntries);

2279

}

2141

free(direntries);

2280

2142

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

2281

2143

exitcode = EXIT_FAILURE;

2282

2144

goto end;

2283

2145

}

2284

2146

}

2285

2147

2286

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

2287

{

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)){

2288

2160

char *interface = NULL;

2289

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

2161

while((interface = argz_next(interfaces, interfaces_size,

2290

2162

interface))){

2291

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

2292

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

2293

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

2294

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

2295

interface);

2296

interface = NULL;

2297

while((interface = argz_next(mc.interfaces,

2298

mc.interfaces_size, interface))){

2299

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

2300

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

2301

interface);

2302

interface = NULL;

2303

}

2304

}

2305

break;

2306

}

2307

2163

bool interface_was_up = interface_is_up(interface);

2308

errno = bring_up_interface(interface, delay);

2164

ret = bring_up_interface(interface, delay);

2309

2165

if(not interface_was_up){

2310

if(errno != 0){

2166

if(ret != 0){

2167

errno = ret;

2311

2168

perror_plus("Failed to bring up interface");

2312

2169

} else {

2313

errno = argz_add(&interfaces_to_take_down,

2314

&interfaces_to_take_down_size,

2315

interface);

2316

if(errno != 0){

2317

perror_plus("argz_add");

2318

}

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

2319

2173

}

2320

2174

}

2321

2175

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2322

2179

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

2323

2180

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

2324

2181

}

2325

2182

}

2326

2183

2327

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

2328

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

2329

if(debug){

2330

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

2331

mc.interfaces);

2332

}

2333

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

2334

}

2335

2336

2184

if(quit_now){

2337

2185

goto end;

2338

2186

}

2339

2187

2340

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

2188

ret = init_gnutls_global(pubkey, seckey);

2341

2189

if(ret == -1){

2342

2190

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

2343

2191

exitcode = EX_UNAVAILABLE;

2350

2198

goto end;

2351

2199

}

2352

2200

2353

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

2354

tempdir = mkdtemp(run_tempdir);

2355

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

2356

if(debug){

2357

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

2358

run_tempdir, old_tempdir);

2359

}

2360

tempdir = mkdtemp(old_tempdir);

2361

}

2362

if(tempdir == NULL){

2201

if(mkdtemp(tempdir) == NULL){

2363

2202

perror_plus("mkdtemp");

2364

2203

goto end;

2365

2204

}

2205

tempdir_created = true;

2366

2206

2367

2207

if(quit_now){

2368

2208

goto end;

2369

2209

}

2370

2210

2371

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

2211

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

2372

2212

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

2373

2213

exitcode = EX_UNAVAILABLE;

2374

2214

goto end;

2404

2244

exitcode = EX_USAGE;

2405

2245

goto end;

2406

2246

}

2407

2247

2408

2248

if(quit_now){

2409

2249

goto end;

2410

2250

}

2431

2271

}

2432

2272

2433

2273

while(not quit_now){

2434

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

2435

&mc);

2274

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

2436

2275

if(quit_now or ret == 0){

2437

2276

break;

2438

2277

}

2440

2279

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

2441

2280

(int)retry_interval);

2442

2281

}

2443

sleep((unsigned int)retry_interval);

2282

sleep((int)retry_interval);

2444

2283

}

2445

2284

2446

if(not quit_now){

2285

if (not quit_now){

2447

2286

exitcode = EXIT_SUCCESS;

2448

2287

}

2449

2288

2486

2325

/* Create the Avahi service browser */

2487

2326

sb = avahi_s_service_browser_new(mc.server, if_index,

2488

2327

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2489

NULL, 0, browse_callback,

2490

(void *)&mc);

2328

NULL, 0, browse_callback, NULL);

2491

2329

if(sb == NULL){

2492

2330

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

2493

2331

avahi_strerror(avahi_server_errno(mc.server)));

2504

2342

if(debug){

2505

2343

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

2506

2344

}

2507

2345

2508

2346

ret = avahi_loop_with_timeout(simple_poll,

2509

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

2347

(int)(retry_interval * 1000));

2510

2348

if(debug){

2511

2349

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

2512

2350

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

2519

2357

}

2520

2358

2521

2359

/* Cleanup things */

2522

free(mc.interfaces);

2523

2524

2360

if(sb != NULL)

2525

2361

avahi_s_service_browser_free(sb);

2526

2362

2551

2387

}

2552

2388

}

2553

2389

2554

/* Re-raise privileges */

2390

/* Re-raise priviliges */

2555

2391

{

2556

ret_errno = raise_privileges();

2557

if(ret_errno != 0){

2558

errno = ret_errno;

2559

perror_plus("Failed to raise privileges");

2560

} else {

2561

2562

/* Run network hooks */

2563

run_network_hooks("stop", interfaces_hooks != NULL ?

2564

interfaces_hooks : "", delay);

2565

2566

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

2567

{

2568

char *interface = NULL;

2569

while((interface=argz_next(interfaces_to_take_down,

2570

interfaces_to_take_down_size,

2571

interface))){

2572

ret_errno = take_down_interface(interface);

2573

if(ret_errno != 0){

2574

errno = ret_errno;

2575

perror_plus("Failed to take down interface");

2576

}

2577

}

2578

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

2579

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

2580

" down\n");

2581

}

2582

}

2583

}

2584

2585

ret_errno = lower_privileges_permanently();

2586

if(ret_errno != 0){

2587

errno = ret_errno;

2588

perror_plus("Failed to lower privileges permanently");

2589

}

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();

2590

2417

}

2591

2418

2592

2419

free(interfaces_to_take_down);

2593

2420

free(interfaces_hooks);

2594

2421

2595

2422

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

2596

if(tempdir != NULL){

2423

if(tempdir_created){

2597

2424

struct dirent **direntries = NULL;

2598

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

2599

O_NOFOLLOW));

2600

if(tempdir_fd == -1){

2601

perror_plus("open");

2602

} else {

2603

#ifdef __GLIBC__

2604

#if __GLIBC_PREREQ(2, 15)

2605

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

2606

notdotentries, alphasort);

2607

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

2608

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

2609

alphasort);

2610

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

2611

#else /* not __GLIBC__ */

2612

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

2613

alphasort);

2614

#endif /* not __GLIBC__ */

2615

if(numentries >= 0){

2616

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

2617

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

2618

if(ret == -1){

2619

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

2620

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

2621

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

2622

}

2623

}

2624

2625

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

2626

free(direntries);

2627

if(numentries == -1){

2628

perror_plus("scandir");

2629

}

2630

ret = rmdir(tempdir);

2631

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

2632

perror_plus("rmdir");

2633

}

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);

2634

2444

}

2635

TEMP_FAILURE_RETRY(close(tempdir_fd));

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");

2636

2455

}

2637

2456

}

2638

2457