/mandos/trunk : revision 709

9

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

10

*

11

* Everything else is

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13

12

13

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*

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(),

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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){

225

236

perror_plus("strdup");

226

237

return false;

227

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

243

}

228

244

/* Special case of first server */

229

if (mc.current_server == NULL){

245

if(*current_server == NULL){

230

246

new_server->next = new_server;

231

247

new_server->prev = new_server;

232

mc.current_server = new_server;

233

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

248

*current_server = new_server;

234

249

} else {

235

new_server->next = mc.current_server;

236

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

250

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

251

new_server->next = *current_server;

252

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

237

253

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;

254

(*current_server)->prev = new_server;

244

255

}

245

256

return true;

246

257

}

248

259

/*

249

260

* Initialize GPGME.

250

261

*/

251

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

252

const char *tempdir){

262

__attribute__((nonnull, warn_unused_result))

263

static bool init_gpgme(const char * const seckey,

264

const char * const pubkey,

265

const char * const tempdir,

266

mandos_context *mc){

253

267

gpgme_error_t rc;

254

268

gpgme_engine_info_t engine_info;

255

269

256

270

/*

257

271

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

258

272

*/

259

bool import_key(const char *filename){

273

bool import_key(const char * const filename){

260

274

int ret;

261

275

int fd;

262

276

gpgme_data_t pgp_data;

274

288

return false;

275

289

}

276

290

277

rc = gpgme_op_import(mc.ctx, pgp_data);

291

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

278

292

if(rc != GPG_ERR_NO_ERROR){

279

293

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

280

294

gpgme_strsource(rc), gpgme_strerror(rc));

324

338

}

325

339

326

340

/* Create new GPGME "context" */

327

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

341

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

328

342

if(rc != GPG_ERR_NO_ERROR){

329

343

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

330

344

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

343

357

* Decrypt OpenPGP data.

344

358

* Returns -1 on error

345

359

*/

360

__attribute__((nonnull, warn_unused_result))

346

361

static ssize_t pgp_packet_decrypt(const char *cryptotext,

347

362

size_t crypto_size,

348

char **plaintext){

363

char **plaintext,

364

mandos_context *mc){

349

365

gpgme_data_t dh_crypto, dh_plain;

350

366

gpgme_error_t rc;

351

367

ssize_t ret;

377

393

378

394

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

379

395

data buffer */

380

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

396

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

381

397

if(rc != GPG_ERR_NO_ERROR){

382

398

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

383

399

gpgme_strsource(rc), gpgme_strerror(rc));

384

400

plaintext_length = -1;

385

401

if(debug){

386

402

gpgme_decrypt_result_t result;

387

result = gpgme_op_decrypt_result(mc.ctx);

403

result = gpgme_op_decrypt_result(mc->ctx);

388

404

if(result == NULL){

389

405

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

390

406

} else {

467

483

return plaintext_length;

468

484

}

469

485

470

static const char * safer_gnutls_strerror(int value){

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

471

488

const char *ret = gnutls_strerror(value);

472

489

if(ret == NULL)

473

490

ret = "(unknown)";

475

492

}

476

493

477

494

/* GnuTLS log function callback */

495

__attribute__((nonnull))

478

496

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

479

497

const char* string){

480

498

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

481

499

}

482

500

501

__attribute__((nonnull, warn_unused_result))

483

502

static int init_gnutls_global(const char *pubkeyfilename,

484

const char *seckeyfilename){

503

const char *seckeyfilename,

504

mandos_context *mc){

485

505

int ret;

486

506

487

507

if(debug){

504

524

}

505

525

506

526

/* OpenPGP credentials */

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

508

528

if(ret != GNUTLS_E_SUCCESS){

509

529

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

510

530

safer_gnutls_strerror(ret));

520

540

}

521

541

522

542

ret = gnutls_certificate_set_openpgp_key_file

523

(mc.cred, pubkeyfilename, seckeyfilename,

543

(mc->cred, pubkeyfilename, seckeyfilename,

524

544

GNUTLS_OPENPGP_FMT_BASE64);

525

545

if(ret != GNUTLS_E_SUCCESS){

526

546

fprintf_plus(stderr,

532

552

}

533

553

534

554

/* GnuTLS server initialization */

535

ret = gnutls_dh_params_init(&mc.dh_params);

555

ret = gnutls_dh_params_init(&mc->dh_params);

536

556

if(ret != GNUTLS_E_SUCCESS){

537

557

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

558

" initialization: %s\n",

539

559

safer_gnutls_strerror(ret));

540

560

goto globalfail;

541

561

}

542

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

562

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

543

563

if(ret != GNUTLS_E_SUCCESS){

544

564

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

545

565

safer_gnutls_strerror(ret));

546

566

goto globalfail;

547

567

}

548

568

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

569

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

550

570

551

571

return 0;

552

572

553

573

globalfail:

554

574

555

gnutls_certificate_free_credentials(mc.cred);

575

gnutls_certificate_free_credentials(mc->cred);

556

576

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

577

gnutls_dh_params_deinit(mc->dh_params);

558

578

return -1;

559

579

}

560

580

561

static int init_gnutls_session(gnutls_session_t *session){

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

562

584

int ret;

563

585

/* GnuTLS session creation */

564

586

do {

576

598

{

577

599

const char *err;

578

600

do {

579

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

601

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

580

602

if(quit_now){

581

603

gnutls_deinit(*session);

582

604

return -1;

593

615

594

616

do {

595

617

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

596

mc.cred);

618

mc->cred);

597

619

if(quit_now){

598

620

gnutls_deinit(*session);

599

621

return -1;

609

631

/* ignore client certificate if any. */

610

632

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

611

633

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

613

635

614

636

return 0;

615

637

}

619

641

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

620

642

621

643

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

622

645

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

623

646

AvahiIfIndex if_index,

624

int af){

647

int af, mandos_context *mc){

625

648

int ret, tcp_sd = -1;

626

649

ssize_t sret;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

650

struct sockaddr_storage to;

631

651

char *buffer = NULL;

632

652

char *decrypted_buffer = NULL;

633

653

size_t buffer_length = 0;

657

677

return -1;

658

678

}

659

679

660

ret = init_gnutls_session(&session);

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);

661

713

if(ret != 0){

662

714

return -1;

663

715

}

682

734

683

735

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

684

736

if(af == AF_INET6){

685

to.in6.sin6_family = (sa_family_t)af;

686

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

737

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

738

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

687

739

} else { /* IPv4 */

688

to.in.sin_family = (sa_family_t)af;

689

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

740

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

741

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

690

742

}

691

743

if(ret < 0 ){

692

744

int e = errno;

701

753

goto mandos_end;

702

754

}

703

755

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*/

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

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

708

759

if(if_index == AVAHI_IF_UNSPEC){

709

760

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

710

761

" incomplete without a network interface\n");

712

763

goto mandos_end;

713

764

}

714

765

/* Set the network interface number as scope */

715

to.in6.sin6_scope_id = (uint32_t)if_index;

766

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

716

767

}

717

768

} else {

718

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

719

-Wconversion and

720

-Wunreachable-code */

769

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

721

770

}

722

771

723

772

if(quit_now){

740

789

}

741

790

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

742

791

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

743

const char *pcret;

744

792

if(af == AF_INET6){

745

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

746

sizeof(addrstr));

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

747

797

} else {

748

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

749

sizeof(addrstr));

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

750

802

}

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

}

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);

757

809

}

758

810

}

759

811

763

815

}

764

816

765

817

if(af == AF_INET6){

766

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

818

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

819

sizeof(struct sockaddr_in6));

767

820

} else {

768

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

821

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

822

sizeof(struct sockaddr_in));

769

823

}

770

824

if(ret < 0){

771

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

825

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

772

826

int e = errno;

773

827

perror_plus("connect");

774

828

errno = e;

935

989

if(buffer_length > 0){

936

990

ssize_t decrypted_buffer_size;

937

991

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

938

&decrypted_buffer);

992

&decrypted_buffer, mc);

939

993

if(decrypted_buffer_size >= 0){

940

994

941

995

written = 0;

989

1043

return retval;

990

1044

}

991

1045

1046

__attribute__((nonnull))

992

1047

static void resolve_callback(AvahiSServiceResolver *r,

993

1048

AvahiIfIndex interface,

994

1049

AvahiProtocol proto,

1002

1057

AVAHI_GCC_UNUSED AvahiStringList *txt,

1003

1058

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1004

1059

flags,

1005

AVAHI_GCC_UNUSED void* userdata){

1060

void *mc){

1006

1061

if(r == NULL){

1007

1062

return;

1008

1063

}

1020

1075

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

1021

1076

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

1022

1077

domain,

1023

avahi_strerror(avahi_server_errno(mc.server)));

1078

avahi_strerror(avahi_server_errno

1079

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

1024

1080

break;

1025

1081

1026

1082

case AVAHI_RESOLVER_FOUND:

1034

1090

}

1035

1091

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

1036

1092

interface,

1037

avahi_proto_to_af(proto));

1093

avahi_proto_to_af(proto),

1094

mc);

1038

1095

if(ret == 0){

1039

1096

avahi_simple_poll_quit(simple_poll);

1040

1097

} else {

1041

1098

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

1042

avahi_proto_to_af(proto))){

1099

avahi_proto_to_af(proto),

1100

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

1043

1101

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

1044

1102

" list\n", name);

1045

1103

}

1058

1116

const char *domain,

1059

1117

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1060

1118

flags,

1061

AVAHI_GCC_UNUSED void* userdata){

1119

void *mc){

1062

1120

if(b == NULL){

1063

1121

return;

1064

1122

}

1075

1133

case AVAHI_BROWSER_FAILURE:

1076

1134

1077

1135

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

1078

avahi_strerror(avahi_server_errno(mc.server)));

1136

avahi_strerror(avahi_server_errno

1137

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

1079

1138

avahi_simple_poll_quit(simple_poll);

1080

1139

return;

1081

1140

1085

1144

the callback function is called the Avahi server will free the

1086

1145

resolver for us. */

1087

1146

1088

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

1089

name, type, domain, protocol, 0,

1090

resolve_callback, NULL) == NULL)

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)

1091

1151

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

1092

1152

" %s\n", name,

1093

avahi_strerror(avahi_server_errno(mc.server)));

1153

avahi_strerror(avahi_server_errno

1154

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

1094

1155

break;

1095

1156

1096

1157

case AVAHI_BROWSER_REMOVE:

1121

1182

errno = old_errno;

1122

1183

}

1123

1184

1185

__attribute__((nonnull, warn_unused_result))

1124

1186

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

1125

1187

int ret;

1126

1188

error_t ret_errno;

1145

1207

return true;

1146

1208

}

1147

1209

1210

__attribute__((nonnull, warn_unused_result))

1148

1211

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

1149

1212

1150

1213

/* Reject the loopback device */

1192

1255

* corresponds to an acceptable network device.

1193

1256

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

1194

1257

*/

1258

__attribute__((nonnull, warn_unused_result))

1195

1259

int good_interface(const struct dirent *if_entry){

1196

1260

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

1197

1261

return 0;

1215

1279

/*

1216

1280

* This function determines if a network interface is up.

1217

1281

*/

1282

__attribute__((nonnull, warn_unused_result))

1218

1283

bool interface_is_up(const char *interface){

1219

1284

struct ifreq ifr;

1220

1285

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

1231

1296

/*

1232

1297

* This function determines if a network interface is running

1233

1298

*/

1299

__attribute__((nonnull, warn_unused_result))

1234

1300

bool interface_is_running(const char *interface){

1235

1301

struct ifreq ifr;

1236

1302

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

1244

1310

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

1245

1311

}

1246

1312

1313

__attribute__((nonnull, pure, warn_unused_result))

1247

1314

int notdotentries(const struct dirent *direntry){

1248

1315

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

1249

1316

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

1256

1323

}

1257

1324

1258

1325

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

1326

__attribute__((nonnull, warn_unused_result))

1259

1327

int runnable_hook(const struct dirent *direntry){

1260

1328

int ret;

1261

1329

size_t sret;

1269

1337

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

1270

1338

"abcdefghijklmnopqrstuvwxyz"

1271

1339

"0123456789"

1272

"_-");

1340

"_.-");

1273

1341

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

1274

1342

/* Contains non-allowed characters */

1275

1343

if(debug){

1279

1347

return 0;

1280

1348

}

1281

1349

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);

1350

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

1290

1351

if(ret == -1){

1291

1352

if(debug){

1292

1353

perror_plus("Could not stat hook");

1316

1377

return 1;

1317

1378

}

1318

1379

1319

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1320

1383

int ret;

1321

1384

struct timespec now;

1322

1385

struct timespec waited_time;

1323

1386

intmax_t block_time;

1324

1387

1325

1388

while(true){

1326

if(mc.current_server == NULL){

1327

if (debug){

1389

if(mc->current_server == NULL){

1390

if(debug){

1328

1391

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

1329

1392

" No timeout!\n");

1330

1393

}

1331

1394

ret = avahi_simple_poll_iterate(s, -1);

1332

1395

} else {

1333

if (debug){

1396

if(debug){

1334

1397

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

1335

1398

" it, or wait\n");

1336

1399

}

1343

1406

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

1344

1407

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

1345

1408

waited_time.tv_sec = (now.tv_sec

1346

- mc.current_server->last_seen.tv_sec);

1409

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

1347

1410

waited_time.tv_nsec = (now.tv_nsec

1348

- mc.current_server->last_seen.tv_nsec);

1411

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

1349

1412

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

1350

1413

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

1351

1414

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

1353

1416

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

1354

1417

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

1355

1418

1356

if (debug){

1419

if(debug){

1357

1420

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

1358

1421

block_time);

1359

1422

}

1360

1423

1361

1424

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);

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);

1366

1429

if(ret == 0){

1367

avahi_simple_poll_quit(simple_poll);

1430

avahi_simple_poll_quit(s);

1368

1431

return 0;

1369

1432

}

1370

1433

ret = clock_gettime(CLOCK_MONOTONIC,

1371

&mc.current_server->last_seen);

1434

&mc->current_server->last_seen);

1372

1435

if(ret == -1){

1373

1436

perror_plus("clock_gettime");

1374

1437

return -1;

1375

1438

}

1376

mc.current_server = mc.current_server->next;

1439

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

1377

1440

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

1378

1441

servers, but don't block */

1379

1442

}

1381

1444

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

1382

1445

}

1383

1446

if(ret != 0){

1384

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

1447

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

1385

1448

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

1386

1449

}

1387

1450

}

1389

1452

}

1390

1453

1391

1454

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

1455

__attribute__((warn_unused_result))

1392

1456

error_t raise_privileges(void){

1393

1457

error_t old_errno = errno;

1394

1458

error_t ret_errno = 0;

1395

1459

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

1396

1460

ret_errno = errno;

1397

perror_plus("seteuid");

1398

1461

}

1399

1462

errno = old_errno;

1400

1463

return ret_errno;

1401

1464

}

1402

1465

1403

1466

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

1467

__attribute__((warn_unused_result))

1404

1468

error_t raise_privileges_permanently(void){

1405

1469

error_t old_errno = errno;

1406

1470

error_t ret_errno = raise_privileges();

1410

1474

}

1411

1475

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

1412

1476

ret_errno = errno;

1413

perror_plus("seteuid");

1414

1477

}

1415

1478

errno = old_errno;

1416

1479

return ret_errno;

1417

1480

}

1418

1481

1419

1482

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

1483

__attribute__((warn_unused_result))

1420

1484

error_t lower_privileges(void){

1421

1485

error_t old_errno = errno;

1422

1486

error_t ret_errno = 0;

1423

1487

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

1424

1488

ret_errno = errno;

1425

perror_plus("seteuid");

1426

1489

}

1427

1490

errno = old_errno;

1428

1491

return ret_errno;

1429

1492

}

1430

1493

1431

1494

/* Lower privileges permanently */

1495

__attribute__((warn_unused_result))

1432

1496

error_t lower_privileges_permanently(void){

1433

1497

error_t old_errno = errno;

1434

1498

error_t ret_errno = 0;

1435

1499

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

1436

1500

ret_errno = errno;

1437

perror_plus("setuid");

1438

1501

}

1439

1502

errno = old_errno;

1440

1503

return ret_errno;

1441

1504

}

1442

1505

1443

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

1506

__attribute__((nonnull))

1507

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

1444

1508

const float delay){

1445

struct dirent **direntries;

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__ */

1536

if(numhooks == -1){

1537

perror_plus("scandir");

1538

return;

1539

}

1446

1540

struct dirent *direntry;

1447

1541

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");

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);

1458

1548

}

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){

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){

1466

1610

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

}

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1525

1615

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

}

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;

1537

1659

} 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;

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);

1574

1677

}

1575

1678

1679

__attribute__((nonnull, warn_unused_result))

1576

1680

error_t bring_up_interface(const char *const interface,

1577

1681

const float delay){

1578

int sd = -1;

1579

1682

error_t old_errno = errno;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1683

int ret;

1582

1684

struct ifreq network;

1583

1685

unsigned int if_index = if_nametoindex(interface);

1584

1686

if(if_index == 0){

1593

1695

}

1594

1696

1595

1697

if(not interface_is_up(interface)){

1596

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

1698

error_t ret_errno = 0, ioctl_errno = 0;

1699

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

1597

1700

ret_errno = errno;

1598

1701

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

1599

1702

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

1703

errno = old_errno;

1600

1704

return ret_errno;

1601

1705

}

1602

network.ifr_flags |= IFF_UP;

1706

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

1603

1707

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1708

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

1709

if(sd == -1){

1606

1710

ret_errno = errno;

1607

1711

perror_plus("socket");

1608

1712

errno = old_errno;

1609

1713

return ret_errno;

1610

1714

}

1611

1715

1612

1716

if(quit_now){

1613

close(sd);

1717

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

1718

if(ret == -1){

1719

perror_plus("close");

1720

}

1614

1721

errno = old_errno;

1615

1722

return EINTR;

1616

1723

}

1620

1727

interface);

1621

1728

}

1622

1729

1623

/* Raise priviliges */

1624

raise_privileges();

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

}

1625

1736

1626

1737

#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");

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

}

1634

1749

}

1635

1750

#endif /* __linux__ */

1636

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

1637

ret_errno = errno;

1751

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

1752

ioctl_errno = errno;

1638

1753

#ifdef __linux__

1639

1754

if(restore_loglevel){

1640

1755

ret_linux = klogctl(7, NULL, 0);

1644

1759

}

1645

1760

#endif /* __linux__ */

1646

1761

1647

/* Lower privileges */

1648

lower_privileges();

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

}

1649

1771

1650

1772

/* Close the socket */

1651

1773

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

1654

1776

}

1655

1777

1656

1778

if(ret_setflags == -1){

1657

errno = ret_errno;

1779

errno = ioctl_errno;

1658

1780

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1659

1781

errno = old_errno;

1660

return ret_errno;

1782

return ioctl_errno;

1661

1783

}

1662

1784

} else if(debug){

1663

1785

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

1681

1803

return 0;

1682

1804

}

1683

1805

1806

__attribute__((nonnull, warn_unused_result))

1684

1807

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1686

1808

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1689

1809

struct ifreq network;

1690

1810

unsigned int if_index = if_nametoindex(interface);

1691

1811

if(if_index == 0){

1694

1814

return ENXIO;

1695

1815

}

1696

1816

if(interface_is_up(interface)){

1817

error_t ret_errno = 0, ioctl_errno = 0;

1697

1818

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

1698

1819

ret_errno = errno;

1699

1820

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

1700

1821

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

1822

errno = old_errno;

1701

1823

return ret_errno;

1702

1824

}

1703

1825

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

1704

1826

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1827

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

1828

if(sd == -1){

1707

1829

ret_errno = errno;

1708

1830

perror_plus("socket");

1709

1831

errno = old_errno;

1715

1837

interface);

1716

1838

}

1717

1839

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();

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

}

1726

1859

1727

1860

/* Close the socket */

1728

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

1861

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

1729

1862

if(ret == -1){

1730

1863

perror_plus("close");

1731

1864

}

1732

1865

1733

1866

if(ret_setflags == -1){

1734

errno = ret_errno;

1867

errno = ioctl_errno;

1735

1868

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1736

1869

errno = old_errno;

1737

return ret_errno;

1870

return ioctl_errno;

1738

1871

}

1739

1872

} else if(debug){

1740

1873

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

1746

1879

}

1747

1880

1748

1881

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 };

1749

1886

AvahiSServiceBrowser *sb = NULL;

1750

1887

error_t ret_errno;

1751

1888

int ret;

1752

1889

intmax_t tmpmax;

1753

1890

char *tmp;

1754

1891

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1757

1892

char *interfaces_to_take_down = NULL;

1758

1893

size_t interfaces_to_take_down_size = 0;

1759

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

1760

bool tempdir_created = false;

1894

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

1895

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

1896

char *tempdir = NULL;

1761

1897

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1762

1898

const char *seckey = PATHDIR "/" SECKEY;

1763

1899

const char *pubkey = PATHDIR "/" PUBKEY;

1764

1900

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1766

1901

1767

1902

bool gnutls_initialized = false;

1768

1903

bool gpgme_initialized = false;

1859

1994

connect_to = arg;

1860

1995

break;

1861

1996

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

1862

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

1863

(int)',');

1997

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

1998

arg, (int)',');

1864

1999

if(ret_errno != 0){

1865

2000

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

1866

2001

}

1946

2081

/* Work around Debian bug #633582:

1947

2082

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

1948

2083

1949

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

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 {

1951

2090

struct stat st;

1952

2091

1953

2092

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

1993

2132

}

1994

2133

1995

2134

/* Lower privileges */

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

2000

2139

}

2001

2140

}

2002

2141

}

2003

2142

2004

/* Remove empty interface names */

2143

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

2005

2144

{

2006

2145

char *interface = NULL;

2007

while((interface = argz_next(interfaces, interfaces_size,

2146

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

2008

2147

interface))){

2009

if(if_nametoindex(interface) == 0){

2010

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

2148

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

2149

and if_nametoindex(interface) == 0){

2150

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

2011

2151

fprintf_plus(stderr, "Not using nonexisting interface"

2012

2152

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

2013

2153

}

2014

argz_delete(&interfaces, &interfaces_size, interface);

2154

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

2015

2155

interface = NULL;

2016

2156

}

2017

2157

}

2019

2159

2020

2160

/* Run network hooks */

2021

2161

{

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2162

if(mc.interfaces != NULL){

2163

interfaces_hooks = malloc(mc.interfaces_size);

2025

2164

if(interfaces_hooks == NULL){

2026

2165

perror_plus("malloc");

2027

2166

goto end;

2028

2167

}

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

}

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);

2038

2173

}

2039

2174

2040

2175

if(not debug){

2117

2252

}

2118

2253

2119

2254

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

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2255

if(mc.interfaces == NULL){

2256

struct dirent **direntries = NULL;

2122

2257

/* Look for any good interfaces */

2123

2258

ret = scandir(sys_class_net, &direntries, good_interface,

2124

2259

alphasort);

2125

2260

if(ret >= 1){

2126

2261

/* Add all found interfaces to interfaces list */

2127

2262

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2263

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

2129

2264

direntries[i]->d_name);

2130

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2131

2267

perror_plus("argz_add");

2132

2268

continue;

2133

2269

}

2138

2274

}

2139

2275

free(direntries);

2140

2276

} else {

2141

free(direntries);

2277

if(ret == 0){

2278

free(direntries);

2279

}

2142

2280

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

2143

2281

exitcode = EXIT_FAILURE;

2144

2282

goto end;

2145

2283

}

2146

2284

}

2147

2285

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)){

2286

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

2287

{

2160

2288

char *interface = NULL;

2161

while((interface = argz_next(interfaces, interfaces_size,

2289

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

2162

2290

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

}

2163

2307

bool interface_was_up = interface_is_up(interface);

2164

ret = bring_up_interface(interface, delay);

2308

errno = bring_up_interface(interface, delay);

2165

2309

if(not interface_was_up){

2166

if(ret != 0){

2167

errno = ret;

2310

if(errno != 0){

2168

2311

perror_plus("Failed to bring up interface");

2169

2312

} else {

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

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

}

2173

2319

}

2174

2320

}

2175

2321

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2179

2322

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

2180

2323

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

2181

2324

}

2182

2325

}

2183

2326

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

2184

2336

if(quit_now){

2185

2337

goto end;

2186

2338

}

2187

2339

2188

ret = init_gnutls_global(pubkey, seckey);

2340

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

2189

2341

if(ret == -1){

2190

2342

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

2191

2343

exitcode = EX_UNAVAILABLE;

2198

2350

goto end;

2199

2351

}

2200

2352

2201

if(mkdtemp(tempdir) == NULL){

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){

2202

2363

perror_plus("mkdtemp");

2203

2364

goto end;

2204

2365

}

2205

tempdir_created = true;

2206

2366

2207

2367

if(quit_now){

2208

2368

goto end;

2209

2369

}

2210

2370

2211

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

2371

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

2212

2372

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

2213

2373

exitcode = EX_UNAVAILABLE;

2214

2374

goto end;

2244

2404

exitcode = EX_USAGE;

2245

2405

goto end;

2246

2406

}

2247

2407

2248

2408

if(quit_now){

2249

2409

goto end;

2250

2410

}

2271

2431

}

2272

2432

2273

2433

while(not quit_now){

2274

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

2434

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

2435

&mc);

2275

2436

if(quit_now or ret == 0){

2276

2437

break;

2277

2438

}

2279

2440

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

2280

2441

(int)retry_interval);

2281

2442

}

2282

sleep((int)retry_interval);

2443

sleep((unsigned int)retry_interval);

2283

2444

}

2284

2445

2285

if (not quit_now){

2446

if(not quit_now){

2286

2447

exitcode = EXIT_SUCCESS;

2287

2448

}

2288

2449

2325

2486

/* Create the Avahi service browser */

2326

2487

sb = avahi_s_service_browser_new(mc.server, if_index,

2327

2488

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2328

NULL, 0, browse_callback, NULL);

2489

NULL, 0, browse_callback,

2490

(void *)&mc);

2329

2491

if(sb == NULL){

2330

2492

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

2331

2493

avahi_strerror(avahi_server_errno(mc.server)));

2342

2504

if(debug){

2343

2505

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

2344

2506

}

2345

2507

2346

2508

ret = avahi_loop_with_timeout(simple_poll,

2347

(int)(retry_interval * 1000));

2509

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

2348

2510

if(debug){

2349

2511

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

2350

2512

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

2357

2519

}

2358

2520

2359

2521

/* Cleanup things */

2522

free(mc.interfaces);

2523

2360

2524

if(sb != NULL)

2361

2525

avahi_s_service_browser_free(sb);

2362

2526

2387

2551

}

2388

2552

}

2389

2553

2390

/* Re-raise priviliges */

2554

/* Re-raise privileges */

2391

2555

{

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();

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

}

2417

2590

}

2418

2591

2419

2592

free(interfaces_to_take_down);

2420

2593

free(interfaces_hooks);

2421

2594

2422

2595

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

2423

if(tempdir_created){

2596

if(tempdir != NULL){

2424

2597

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);

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

}

2444

2634

}

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");

2635

TEMP_FAILURE_RETRY(close(tempdir_fd));

2455

2636

}

2456

2637

}

2457

2638