/mandos/release : revision 237.7.149

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(),

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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){

234

223

.af = af };

235

224

if(new_server->ip == NULL){

236

225

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

free((char *)(new_server->ip));

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

226

return false;

253

227

}

254

228

/* Special case of first server */

255

if(*current_server == NULL){

229

if (mc.current_server == NULL){

256

230

new_server->next = new_server;

257

231

new_server->prev = new_server;

258

*current_server = new_server;

232

mc.current_server = new_server;

233

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

259

234

} else {

260

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

261

new_server->next = *current_server;

262

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

235

new_server->next = mc.current_server;

236

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

263

237

new_server->prev->next = new_server;

264

(*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;

265

244

}

266

245

return true;

267

246

}

269

248

/*

270

249

* Initialize GPGME.

271

250

*/

272

__attribute__((nonnull, warn_unused_result))

273

static bool init_gpgme(const char * const seckey,

274

const char * const pubkey,

275

const char * const tempdir,

276

mandos_context *mc){

251

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

252

const char *tempdir){

277

253

gpgme_error_t rc;

278

254

gpgme_engine_info_t engine_info;

279

255

280

256

/*

281

257

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

282

258

*/

283

bool import_key(const char * const filename){

259

bool import_key(const char *filename){

284

260

int ret;

285

261

int fd;

286

262

gpgme_data_t pgp_data;

298

274

return false;

299

275

}

300

276

301

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

277

rc = gpgme_op_import(mc.ctx, pgp_data);

302

278

if(rc != GPG_ERR_NO_ERROR){

303

279

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

304

280

gpgme_strsource(rc), gpgme_strerror(rc));

348

324

}

349

325

350

326

/* Create new GPGME "context" */

351

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

327

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

352

328

if(rc != GPG_ERR_NO_ERROR){

353

329

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

354

330

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

367

343

* Decrypt OpenPGP data.

368

344

* Returns -1 on error

369

345

*/

370

__attribute__((nonnull, warn_unused_result))

371

346

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

347

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

348

char **plaintext){

375

349

gpgme_data_t dh_crypto, dh_plain;

376

350

gpgme_error_t rc;

377

351

ssize_t ret;

403

377

404

378

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

405

379

data buffer */

406

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

380

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

407

381

if(rc != GPG_ERR_NO_ERROR){

408

382

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

409

383

gpgme_strsource(rc), gpgme_strerror(rc));

410

384

plaintext_length = -1;

411

385

if(debug){

412

386

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

387

result = gpgme_op_decrypt_result(mc.ctx);

414

388

if(result == NULL){

415

389

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

416

390

} else {

493

467

return plaintext_length;

494

468

}

495

469

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

470

static const char * safer_gnutls_strerror(int value){

498

471

const char *ret = gnutls_strerror(value);

499

472

if(ret == NULL)

500

473

ret = "(unknown)";

502

475

}

503

476

504

477

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

478

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

507

479

const char* string){

508

480

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

509

481

}

510

482

511

__attribute__((nonnull, warn_unused_result))

512

483

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

484

const char *seckeyfilename){

515

485

int ret;

516

486

517

487

if(debug){

534

504

}

535

505

536

506

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

508

if(ret != GNUTLS_E_SUCCESS){

539

509

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

540

510

safer_gnutls_strerror(ret));

550

520

}

551

521

552

522

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

523

(mc.cred, pubkeyfilename, seckeyfilename,

554

524

GNUTLS_OPENPGP_FMT_BASE64);

555

525

if(ret != GNUTLS_E_SUCCESS){

556

526

fprintf_plus(stderr,

562

532

}

563

533

564

534

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

535

ret = gnutls_dh_params_init(&mc.dh_params);

566

536

if(ret != GNUTLS_E_SUCCESS){

567

537

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

538

" initialization: %s\n",

569

539

safer_gnutls_strerror(ret));

570

540

goto globalfail;

571

541

}

572

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

542

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

573

543

if(ret != GNUTLS_E_SUCCESS){

574

544

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

575

545

safer_gnutls_strerror(ret));

576

546

goto globalfail;

577

547

}

578

548

579

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

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

550

581

551

return 0;

582

552

583

553

globalfail:

584

554

585

gnutls_certificate_free_credentials(mc->cred);

555

gnutls_certificate_free_credentials(mc.cred);

586

556

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

557

gnutls_dh_params_deinit(mc.dh_params);

588

558

return -1;

589

559

}

590

560

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

561

static int init_gnutls_session(gnutls_session_t *session){

594

562

int ret;

595

563

/* GnuTLS session creation */

596

564

do {

608

576

{

609

577

const char *err;

610

578

do {

611

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

579

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

612

580

if(quit_now){

613

581

gnutls_deinit(*session);

614

582

return -1;

625

593

626

594

do {

627

595

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

596

mc.cred);

629

597

if(quit_now){

630

598

gnutls_deinit(*session);

631

599

return -1;

641

609

/* ignore client certificate if any. */

642

610

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

611

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

613

646

614

return 0;

647

615

}

651

619

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

652

620

653

621

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

655

622

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

656

623

AvahiIfIndex if_index,

657

int af, mandos_context *mc){

624

int af){

658

625

int ret, tcp_sd = -1;

659

626

ssize_t sret;

660

struct sockaddr_storage to;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

661

631

char *buffer = NULL;

662

632

char *decrypted_buffer = NULL;

663

633

size_t buffer_length = 0;

687

657

return -1;

688

658

}

689

659

690

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

691

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

692

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

693

bool match = false;

694

{

695

char *interface = NULL;

696

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

697

interface))){

698

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

699

match = true;

700

break;

701

}

702

}

703

}

704

if(not match){

705

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

706

connect to the server */

707

if(debug){

708

char interface[IF_NAMESIZE];

709

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

710

perror_plus("if_indextoname");

711

} else {

712

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

713

" \"%s\"\n",

714

if_indextoname((unsigned int)if_index,

715

interface));

716

}

717

}

718

return -1;

719

}

720

}

721

722

ret = init_gnutls_session(&session, mc);

660

ret = init_gnutls_session(&session);

723

661

if(ret != 0){

724

662

return -1;

725

663

}

744

682

745

683

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

746

684

if(af == AF_INET6){

747

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

748

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);

749

687

} else { /* IPv4 */

750

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

751

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);

752

690

}

753

691

if(ret < 0 ){

754

692

int e = errno;

763

701

goto mandos_end;

764

702

}

765

703

if(af == AF_INET6){

766

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

767

if(IN6_IS_ADDR_LINKLOCAL

768

(&((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*/

769

708

if(if_index == AVAHI_IF_UNSPEC){

770

709

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

771

710

" incomplete without a network interface\n");

773

712

goto mandos_end;

774

713

}

775

714

/* Set the network interface number as scope */

776

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

715

to.in6.sin6_scope_id = (uint32_t)if_index;

777

716

}

778

717

} else {

779

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

718

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

719

-Wconversion and

720

-Wunreachable-code */

780

721

}

781

722

782

723

if(quit_now){

799

740

}

800

741

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

801

742

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

743

const char *pcret;

802

744

if(af == AF_INET6){

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

745

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

746

sizeof(addrstr));

807

747

} else {

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

748

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

749

sizeof(addrstr));

812

750

}

813

if(ret == EAI_SYSTEM){

814

perror_plus("getnameinfo");

815

} else if(ret != 0) {

816

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

817

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

818

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

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

}

819

757

}

820

758

}

821

759

825

763

}

826

764

827

765

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

766

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

830

767

} else {

831

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

832

sizeof(struct sockaddr_in));

768

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

833

769

}

834

770

if(ret < 0){

835

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

771

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

836

772

int e = errno;

837

773

perror_plus("connect");

838

774

errno = e;

999

935

if(buffer_length > 0){

1000

936

ssize_t decrypted_buffer_size;

1001

937

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1002

&decrypted_buffer, mc);

938

&decrypted_buffer);

1003

939

if(decrypted_buffer_size >= 0){

1004

940

1005

941

written = 0;

1053

989

return retval;

1054

990

}

1055

991

1056

__attribute__((nonnull))

1057

992

static void resolve_callback(AvahiSServiceResolver *r,

1058

993

AvahiIfIndex interface,

1059

994

AvahiProtocol proto,

1067

1002

AVAHI_GCC_UNUSED AvahiStringList *txt,

1068

1003

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1069

1004

flags,

1070

void *mc){

1005

AVAHI_GCC_UNUSED void* userdata){

1071

1006

if(r == NULL){

1072

1007

return;

1073

1008

}

1076

1011

timed out */

1077

1012

1078

1013

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1080

1014

return;

1081

1015

}

1082

1016

1086

1020

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

1087

1021

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

1088

1022

domain,

1089

avahi_strerror(avahi_server_errno

1090

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

1023

avahi_strerror(avahi_server_errno(mc.server)));

1091

1024

break;

1092

1025

1093

1026

case AVAHI_RESOLVER_FOUND:

1101

1034

}

1102

1035

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

1103

1036

interface,

1104

avahi_proto_to_af(proto),

1105

mc);

1037

avahi_proto_to_af(proto));

1106

1038

if(ret == 0){

1107

1039

avahi_simple_poll_quit(simple_poll);

1108

1040

} else {

1109

1041

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

1110

avahi_proto_to_af(proto),

1111

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

1042

avahi_proto_to_af(proto))){

1112

1043

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

1113

1044

" list\n", name);

1114

1045

}

1127

1058

const char *domain,

1128

1059

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1129

1060

flags,

1130

void *mc){

1061

AVAHI_GCC_UNUSED void* userdata){

1131

1062

if(b == NULL){

1132

1063

return;

1133

1064

}

1144

1075

case AVAHI_BROWSER_FAILURE:

1145

1076

1146

1077

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

1147

avahi_strerror(avahi_server_errno

1148

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

1078

avahi_strerror(avahi_server_errno(mc.server)));

1149

1079

avahi_simple_poll_quit(simple_poll);

1150

1080

return;

1151

1081

1155

1085

the callback function is called the Avahi server will free the

1156

1086

resolver for us. */

1157

1087

1158

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

1159

interface, protocol, name, type,

1160

domain, protocol, 0,

1161

resolve_callback, mc) == NULL)

1088

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

1089

name, type, domain, protocol, 0,

1090

resolve_callback, NULL) == NULL)

1162

1091

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

1163

1092

" %s\n", name,

1164

avahi_strerror(avahi_server_errno

1165

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

1093

avahi_strerror(avahi_server_errno(mc.server)));

1166

1094

break;

1167

1095

1168

1096

case AVAHI_BROWSER_REMOVE:

1193

1121

errno = old_errno;

1194

1122

}

1195

1123

1196

__attribute__((nonnull, warn_unused_result))

1197

1124

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

1198

1125

int ret;

1199

1126

error_t ret_errno;

1218

1145

return true;

1219

1146

}

1220

1147

1221

__attribute__((nonnull, warn_unused_result))

1222

1148

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

1223

1149

1224

1150

/* Reject the loopback device */

1266

1192

* corresponds to an acceptable network device.

1267

1193

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

1268

1194

*/

1269

__attribute__((nonnull, warn_unused_result))

1270

1195

int good_interface(const struct dirent *if_entry){

1271

1196

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

1272

1197

return 0;

1290

1215

/*

1291

1216

* This function determines if a network interface is up.

1292

1217

*/

1293

__attribute__((nonnull, warn_unused_result))

1294

1218

bool interface_is_up(const char *interface){

1295

1219

struct ifreq ifr;

1296

1220

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

1307

1231

/*

1308

1232

* This function determines if a network interface is running

1309

1233

*/

1310

__attribute__((nonnull, warn_unused_result))

1311

1234

bool interface_is_running(const char *interface){

1312

1235

struct ifreq ifr;

1313

1236

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

1321

1244

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

1322

1245

}

1323

1246

1324

__attribute__((nonnull, pure, warn_unused_result))

1325

1247

int notdotentries(const struct dirent *direntry){

1326

1248

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

1327

1249

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

1334

1256

}

1335

1257

1336

1258

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

1337

__attribute__((nonnull, warn_unused_result))

1338

1259

int runnable_hook(const struct dirent *direntry){

1339

1260

int ret;

1340

1261

size_t sret;

1348

1269

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

1349

1270

"abcdefghijklmnopqrstuvwxyz"

1350

1271

"0123456789"

1351

"_.-");

1272

"_-");

1352

1273

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

1353

1274

/* Contains non-allowed characters */

1354

1275

if(debug){

1358

1279

return 0;

1359

1280

}

1360

1281

1361

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);

1362

1290

if(ret == -1){

1363

1291

if(debug){

1364

1292

perror_plus("Could not stat hook");

1388

1316

return 1;

1389

1317

}

1390

1318

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1319

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1394

1320

int ret;

1395

1321

struct timespec now;

1396

1322

struct timespec waited_time;

1397

1323

intmax_t block_time;

1398

1324

1399

1325

while(true){

1400

if(mc->current_server == NULL){

1401

if(debug){

1326

if(mc.current_server == NULL){

1327

if (debug){

1402

1328

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

1403

1329

" No timeout!\n");

1404

1330

}

1405

1331

ret = avahi_simple_poll_iterate(s, -1);

1406

1332

} else {

1407

if(debug){

1333

if (debug){

1408

1334

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

1409

1335

" it, or wait\n");

1410

1336

}

1417

1343

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

1418

1344

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

1419

1345

waited_time.tv_sec = (now.tv_sec

1420

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

1346

- mc.current_server->last_seen.tv_sec);

1421

1347

waited_time.tv_nsec = (now.tv_nsec

1422

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

1348

- mc.current_server->last_seen.tv_nsec);

1423

1349

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

1424

1350

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

1425

1351

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

1427

1353

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

1428

1354

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

1429

1355

1430

if(debug){

1356

if (debug){

1431

1357

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

1432

1358

block_time);

1433

1359

}

1434

1360

1435

1361

if(block_time <= 0){

1436

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

1437

mc->current_server->port,

1438

mc->current_server->if_index,

1439

mc->current_server->af, mc);

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);

1440

1366

if(ret == 0){

1441

avahi_simple_poll_quit(s);

1367

avahi_simple_poll_quit(simple_poll);

1442

1368

return 0;

1443

1369

}

1444

1370

ret = clock_gettime(CLOCK_MONOTONIC,

1445

&mc->current_server->last_seen);

1371

&mc.current_server->last_seen);

1446

1372

if(ret == -1){

1447

1373

perror_plus("clock_gettime");

1448

1374

return -1;

1449

1375

}

1450

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

1376

mc.current_server = mc.current_server->next;

1451

1377

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

1452

1378

servers, but don't block */

1453

1379

}

1455

1381

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

1456

1382

}

1457

1383

if(ret != 0){

1458

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

1384

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

1459

1385

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

1460

1386

}

1461

1387

}

1463

1389

}

1464

1390

1465

1391

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

1466

__attribute__((warn_unused_result))

1467

1392

error_t raise_privileges(void){

1468

1393

error_t old_errno = errno;

1469

1394

error_t ret_errno = 0;

1470

1395

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

1471

1396

ret_errno = errno;

1397

perror_plus("seteuid");

1472

1398

}

1473

1399

errno = old_errno;

1474

1400

return ret_errno;

1475

1401

}

1476

1402

1477

1403

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

1478

__attribute__((warn_unused_result))

1479

1404

error_t raise_privileges_permanently(void){

1480

1405

error_t old_errno = errno;

1481

1406

error_t ret_errno = raise_privileges();

1485

1410

}

1486

1411

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

1487

1412

ret_errno = errno;

1413

perror_plus("seteuid");

1488

1414

}

1489

1415

errno = old_errno;

1490

1416

return ret_errno;

1491

1417

}

1492

1418

1493

1419

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

1494

__attribute__((warn_unused_result))

1495

1420

error_t lower_privileges(void){

1496

1421

error_t old_errno = errno;

1497

1422

error_t ret_errno = 0;

1498

1423

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

1499

1424

ret_errno = errno;

1425

perror_plus("seteuid");

1500

1426

}

1501

1427

errno = old_errno;

1502

1428

return ret_errno;

1503

1429

}

1504

1430

1505

1431

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1507

1432

error_t lower_privileges_permanently(void){

1508

1433

error_t old_errno = errno;

1509

1434

error_t ret_errno = 0;

1510

1435

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

1511

1436

ret_errno = errno;

1437

perror_plus("setuid");

1512

1438

}

1513

1439

errno = old_errno;

1514

1440

return ret_errno;

1515

1441

}

1516

1442

1517

__attribute__((nonnull))

1518

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

1443

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

1519

1444

const float delay){

1520

struct dirent **direntries = NULL;

1521

if(hookdir_fd == -1){

1522

hookdir_fd = open(hookdir, O_RDONLY);

1523

if(hookdir_fd == -1){

1524

if(errno == ENOENT){

1525

if(debug){

1526

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

1527

" found\n", hookdir);

1528

}

1529

} else {

1530

perror_plus("open");

1531

}

1532

return;

1533

}

1534

}

1535

#ifdef __GLIBC__

1536

#if __GLIBC_PREREQ(2, 15)

1537

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

1538

runnable_hook, alphasort);

1539

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

1540

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

1541

alphasort);

1542

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

1543

#else /* not __GLIBC__ */

1544

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

1545

alphasort);

1546

#endif /* not __GLIBC__ */

1445

struct dirent **direntries;

1446

struct dirent *direntry;

1447

int ret;

1448

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

1449

alphasort);

1547

1450

if(numhooks == -1){

1548

perror_plus("scandir");

1549

return;

1550

}

1551

struct dirent *direntry;

1552

int ret;

1553

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

1554

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

1555

direntry = direntries[i];

1556

if(debug){

1557

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

1558

direntry->d_name);

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");

1559

1458

}

1560

pid_t hook_pid = fork();

1561

if(hook_pid == 0){

1562

/* Child */

1563

/* Raise privileges */

1564

errno = raise_privileges_permanently();

1565

if(errno != 0){

1566

perror_plus("Failed to raise privileges");

1567

_exit(EX_NOPERM);

1568

}

1569

/* Set group */

1570

errno = 0;

1571

ret = setgid(0);

1572

if(ret == -1){

1573

perror_plus("setgid");

1574

_exit(EX_NOPERM);

1575

}

1576

/* Reset supplementary groups */

1577

errno = 0;

1578

ret = setgroups(0, NULL);

1579

if(ret == -1){

1580

perror_plus("setgroups");

1581

_exit(EX_NOPERM);

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

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

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

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

1596

_exit(EX_OSERR);

1597

}

1598

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

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

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

1604

if(ret == -1){

1605

perror_plus("setenv");

1606

_exit(EX_OSERR);

1607

}

1608

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

1609

if(ret == -1){

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

perror_plus("setenv");

1616

_exit(EX_OSERR);

1617

}

1618

char *delaystring;

1619

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

1620

if(ret == -1){

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){

1621

1466

perror_plus("asprintf");

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

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

}

1626

1525

free(delaystring);

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

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

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

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

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

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

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

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

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

if(hook_pid == -1){

1654

perror_plus("fork");

1655

free(direntry);

1656

continue;

1657

}

1658

int status;

1659

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

1660

perror_plus("waitpid");

1661

free(direntry);

1662

continue;

1663

}

1664

if(WIFEXITED(status)){

1665

if(WEXITSTATUS(status) != 0){

1666

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

1667

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

1668

WEXITSTATUS(status));

1669

free(direntry);

1670

continue;

1671

}

1672

} else if(WIFSIGNALED(status)){

1673

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

1674

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

1675

WTERMSIG(status));

1676

free(direntry);

1677

continue;

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

}

1678

1537

} else {

1679

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

1680

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

1681

free(direntry);

1682

continue;

1683

}

1684

}

1685

if(debug){

1686

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

1687

direntry->d_name);

1688

}

1689

free(direntry);

1690

}

1691

free(direntries);

1692

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

1693

perror_plus("close");

1694

} else {

1695

hookdir_fd = -1;

1696

}

1697

close(devnull);

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;

1698

1574

}

1699

1575

1700

__attribute__((nonnull, warn_unused_result))

1701

1576

error_t bring_up_interface(const char *const interface,

1702

1577

const float delay){

1578

int sd = -1;

1703

1579

error_t old_errno = errno;

1704

int ret;

1580

error_t ret_errno = 0;

1581

int ret, ret_setflags;

1705

1582

struct ifreq network;

1706

1583

unsigned int if_index = if_nametoindex(interface);

1707

1584

if(if_index == 0){

1716

1593

}

1717

1594

1718

1595

if(not interface_is_up(interface)){

1719

error_t ret_errno = 0, ioctl_errno = 0;

1720

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

1596

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

1721

1597

ret_errno = errno;

1722

1598

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

1723

1599

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

1724

errno = old_errno;

1725

1600

return ret_errno;

1726

1601

}

1727

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

1602

network.ifr_flags |= IFF_UP;

1728

1603

1729

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

1730

if(sd == -1){

1604

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1605

if(sd < 0){

1731

1606

ret_errno = errno;

1732

1607

perror_plus("socket");

1733

1608

errno = old_errno;

1734

1609

return ret_errno;

1735

1610

}

1736

1611

1737

1612

if(quit_now){

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1613

close(sd);

1742

1614

errno = old_errno;

1743

1615

return EINTR;

1744

1616

}

1748

1620

interface);

1749

1621

}

1750

1622

1751

/* Raise privileges */

1752

ret_errno = raise_privileges();

1753

if(ret_errno != 0){

1754

errno = ret_errno;

1755

perror_plus("Failed to raise privileges");

1756

}

1623

/* Raise priviliges */

1624

raise_privileges();

1757

1625

1758

1626

#ifdef __linux__

1759

int ret_linux;

1760

bool restore_loglevel = false;

1761

if(ret_errno == 0){

1762

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1763

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

1764

ret_linux = klogctl(8, NULL, 5);

1765

if(ret_linux == -1){

1766

perror_plus("klogctl");

1767

} else {

1768

restore_loglevel = true;

1769

}

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");

1770

1634

}

1771

1635

#endif /* __linux__ */

1772

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

1773

ioctl_errno = errno;

1636

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

1637

ret_errno = errno;

1774

1638

#ifdef __linux__

1775

1639

if(restore_loglevel){

1776

1640

ret_linux = klogctl(7, NULL, 0);

1780

1644

}

1781

1645

#endif /* __linux__ */

1782

1646

1783

/* If raise_privileges() succeeded above */

1784

if(ret_errno == 0){

1785

/* Lower privileges */

1786

ret_errno = lower_privileges();

1787

if(ret_errno != 0){

1788

errno = ret_errno;

1789

perror_plus("Failed to lower privileges");

1790

}

1791

}

1647

/* Lower privileges */

1648

lower_privileges();

1792

1649

1793

1650

/* Close the socket */

1794

1651

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

1797

1654

}

1798

1655

1799

1656

if(ret_setflags == -1){

1800

errno = ioctl_errno;

1657

errno = ret_errno;

1801

1658

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1802

1659

errno = old_errno;

1803

return ioctl_errno;

1660

return ret_errno;

1804

1661

}

1805

1662

} else if(debug){

1806

1663

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

1824

1681

return 0;

1825

1682

}

1826

1683

1827

__attribute__((nonnull, warn_unused_result))

1828

1684

error_t take_down_interface(const char *const interface){

1685

int sd = -1;

1829

1686

error_t old_errno = errno;

1687

error_t ret_errno = 0;

1688

int ret, ret_setflags;

1830

1689

struct ifreq network;

1831

1690

unsigned int if_index = if_nametoindex(interface);

1832

1691

if(if_index == 0){

1835

1694

return ENXIO;

1836

1695

}

1837

1696

if(interface_is_up(interface)){

1838

error_t ret_errno = 0, ioctl_errno = 0;

1839

1697

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

1840

1698

ret_errno = errno;

1841

1699

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

1842

1700

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

1843

errno = old_errno;

1844

1701

return ret_errno;

1845

1702

}

1846

1703

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

1847

1704

1848

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

1849

if(sd == -1){

1705

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1706

if(sd < 0){

1850

1707

ret_errno = errno;

1851

1708

perror_plus("socket");

1852

1709

errno = old_errno;

1858

1715

interface);

1859

1716

}

1860

1717

1861

/* Raise privileges */

1862

ret_errno = raise_privileges();

1863

if(ret_errno != 0){

1864

errno = ret_errno;

1865

perror_plus("Failed to raise privileges");

1866

}

1867

1868

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

1869

ioctl_errno = errno;

1870

1871

/* If raise_privileges() succeeded above */

1872

if(ret_errno == 0){

1873

/* Lower privileges */

1874

ret_errno = lower_privileges();

1875

if(ret_errno != 0){

1876

errno = ret_errno;

1877

perror_plus("Failed to lower privileges");

1878

}

1879

}

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();

1880

1726

1881

1727

/* Close the socket */

1882

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

1728

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

1883

1729

if(ret == -1){

1884

1730

perror_plus("close");

1885

1731

}

1886

1732

1887

1733

if(ret_setflags == -1){

1888

errno = ioctl_errno;

1734

errno = ret_errno;

1889

1735

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1890

1736

errno = old_errno;

1891

return ioctl_errno;

1737

return ret_errno;

1892

1738

}

1893

1739

} else if(debug){

1894

1740

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

1900

1746

}

1901

1747

1902

1748

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

1903

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

1904

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

1905

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

1906

.interfaces = NULL, .interfaces_size = 0 };

1907

1749

AvahiSServiceBrowser *sb = NULL;

1908

1750

error_t ret_errno;

1909

1751

int ret;

1910

1752

intmax_t tmpmax;

1911

1753

char *tmp;

1912

1754

int exitcode = EXIT_SUCCESS;

1755

char *interfaces = NULL;

1756

size_t interfaces_size = 0;

1913

1757

char *interfaces_to_take_down = NULL;

1914

1758

size_t interfaces_to_take_down_size = 0;

1915

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

1916

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

1917

char *tempdir = NULL;

1759

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

1760

bool tempdir_created = false;

1918

1761

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1919

1762

const char *seckey = PATHDIR "/" SECKEY;

1920

1763

const char *pubkey = PATHDIR "/" PUBKEY;

1921

1764

char *interfaces_hooks = NULL;

1765

size_t interfaces_hooks_size = 0;

1922

1766

1923

1767

bool gnutls_initialized = false;

1924

1768

bool gpgme_initialized = false;

2015

1859

connect_to = arg;

2016

1860

break;

2017

1861

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

2018

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

2019

arg, (int)',');

1862

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

1863

(int)',');

2020

1864

if(ret_errno != 0){

2021

1865

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

2022

1866

}

2102

1946

/* Work around Debian bug #633582:

2103

1947

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

2104

1948

2105

/* Re-raise privileges */

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2109

perror_plus("Failed to raise privileges");

2110

} else {

1949

/* Re-raise priviliges */

1950

if(raise_privileges() == 0){

2111

1951

struct stat st;

2112

1952

2113

1953

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

2153

1993

}

2154

1994

2155

1995

/* Lower privileges */

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2159

perror_plus("Failed to lower privileges");

1996

errno = 0;

1997

ret = seteuid(uid);

1998

if(ret == -1){

1999

perror_plus("seteuid");

2160

2000

}

2161

2001

}

2162

2002

}

2163

2003

2164

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

2004

/* Remove empty interface names */

2165

2005

{

2166

2006

char *interface = NULL;

2167

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

2007

while((interface = argz_next(interfaces, interfaces_size,

2168

2008

interface))){

2169

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

2170

and if_nametoindex(interface) == 0){

2171

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

2009

if(if_nametoindex(interface) == 0){

2010

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

2172

2011

fprintf_plus(stderr, "Not using nonexisting interface"

2173

2012

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

2174

2013

}

2175

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

2014

argz_delete(&interfaces, &interfaces_size, interface);

2176

2015

interface = NULL;

2177

2016

}

2178

2017

}

2180

2019

2181

2020

/* Run network hooks */

2182

2021

{

2183

if(mc.interfaces != NULL){

2184

interfaces_hooks = malloc(mc.interfaces_size);

2022

2023

if(interfaces != NULL){

2024

interfaces_hooks = malloc(interfaces_size);

2185

2025

if(interfaces_hooks == NULL){

2186

2026

perror_plus("malloc");

2187

2027

goto end;

2188

2028

}

2189

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

2190

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

2191

}

2192

run_network_hooks("start", interfaces_hooks != NULL ?

2193

interfaces_hooks : "", delay);

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

}

2194

2038

}

2195

2039

2196

2040

if(not debug){

2273

2117

}

2274

2118

2275

2119

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

2276

if(mc.interfaces == NULL){

2277

struct dirent **direntries = NULL;

2120

if(interfaces == NULL){

2121

struct dirent **direntries;

2278

2122

/* Look for any good interfaces */

2279

2123

ret = scandir(sys_class_net, &direntries, good_interface,

2280

2124

alphasort);

2281

2125

if(ret >= 1){

2282

2126

/* Add all found interfaces to interfaces list */

2283

2127

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

2284

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

2128

ret_errno = argz_add(&interfaces, &interfaces_size,

2285

2129

direntries[i]->d_name);

2286

2130

if(ret_errno != 0){

2287

errno = ret_errno;

2288

2131

perror_plus("argz_add");

2289

free(direntries[i]);

2290

2132

continue;

2291

2133

}

2292

2134

if(debug){

2293

2135

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

2294

2136

direntries[i]->d_name);

2295

2137

}

2296

free(direntries[i]);

2297

2138

}

2298

2139

free(direntries);

2299

2140

} else {

2300

if(ret == 0){

2301

free(direntries);

2302

}

2141

free(direntries);

2303

2142

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

2304

2143

exitcode = EXIT_FAILURE;

2305

2144

goto end;

2306

2145

}

2307

2146

}

2308

2147

2309

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

2310

{

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)){

2311

2160

char *interface = NULL;

2312

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

2161

while((interface = argz_next(interfaces, interfaces_size,

2313

2162

interface))){

2314

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

2315

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

2316

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

2317

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

2318

interface);

2319

interface = NULL;

2320

while((interface = argz_next(mc.interfaces,

2321

mc.interfaces_size, interface))){

2322

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

2323

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

2324

interface);

2325

interface = NULL;

2326

}

2327

}

2328

break;

2329

}

2330

2163

bool interface_was_up = interface_is_up(interface);

2331

errno = bring_up_interface(interface, delay);

2164

ret = bring_up_interface(interface, delay);

2332

2165

if(not interface_was_up){

2333

if(errno != 0){

2166

if(ret != 0){

2167

errno = ret;

2334

2168

perror_plus("Failed to bring up interface");

2335

2169

} else {

2336

errno = argz_add(&interfaces_to_take_down,

2337

&interfaces_to_take_down_size,

2338

interface);

2339

if(errno != 0){

2340

perror_plus("argz_add");

2341

}

2170

ret_errno = argz_add(&interfaces_to_take_down,

2171

&interfaces_to_take_down_size,

2172

interface);

2342

2173

}

2343

2174

}

2344

2175

}

2176

free(interfaces);

2177

interfaces = NULL;

2178

interfaces_size = 0;

2345

2179

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

2346

2180

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

2347

2181

}

2348

2182

}

2349

2183

2350

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

2351

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

2352

if(debug){

2353

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

2354

mc.interfaces);

2355

}

2356

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

2357

}

2358

2359

2184

if(quit_now){

2360

2185

goto end;

2361

2186

}

2362

2187

2363

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

2188

ret = init_gnutls_global(pubkey, seckey);

2364

2189

if(ret == -1){

2365

2190

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

2366

2191

exitcode = EX_UNAVAILABLE;

2373

2198

goto end;

2374

2199

}

2375

2200

2376

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

2377

tempdir = mkdtemp(run_tempdir);

2378

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

2379

if(debug){

2380

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

2381

run_tempdir, old_tempdir);

2382

}

2383

tempdir = mkdtemp(old_tempdir);

2384

}

2385

if(tempdir == NULL){

2201

if(mkdtemp(tempdir) == NULL){

2386

2202

perror_plus("mkdtemp");

2387

2203

goto end;

2388

2204

}

2205

tempdir_created = true;

2389

2206

2390

2207

if(quit_now){

2391

2208

goto end;

2392

2209

}

2393

2210

2394

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

2211

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

2395

2212

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

2396

2213

exitcode = EX_UNAVAILABLE;

2397

2214

goto end;

2427

2244

exitcode = EX_USAGE;

2428

2245

goto end;

2429

2246

}

2430

2247

2431

2248

if(quit_now){

2432

2249

goto end;

2433

2250

}

2454

2271

}

2455

2272

2456

2273

while(not quit_now){

2457

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

2458

&mc);

2274

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

2459

2275

if(quit_now or ret == 0){

2460

2276

break;

2461

2277

}

2463

2279

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

2464

2280

(int)retry_interval);

2465

2281

}

2466

sleep((unsigned int)retry_interval);

2282

sleep((int)retry_interval);

2467

2283

}

2468

2284

2469

if(not quit_now){

2285

if (not quit_now){

2470

2286

exitcode = EXIT_SUCCESS;

2471

2287

}

2472

2288

2509

2325

/* Create the Avahi service browser */

2510

2326

sb = avahi_s_service_browser_new(mc.server, if_index,

2511

2327

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2512

NULL, 0, browse_callback,

2513

(void *)&mc);

2328

NULL, 0, browse_callback, NULL);

2514

2329

if(sb == NULL){

2515

2330

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

2516

2331

avahi_strerror(avahi_server_errno(mc.server)));

2527

2342

if(debug){

2528

2343

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

2529

2344

}

2530

2345

2531

2346

ret = avahi_loop_with_timeout(simple_poll,

2532

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

2347

(int)(retry_interval * 1000));

2533

2348

if(debug){

2534

2349

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

2535

2350

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

2542

2357

}

2543

2358

2544

2359

/* Cleanup things */

2545

free(mc.interfaces);

2546

2547

2360

if(sb != NULL)

2548

2361

avahi_s_service_browser_free(sb);

2549

2362

2569

2382

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

2570

2383

while(mc.current_server != NULL){

2571

2384

server *next = mc.current_server->next;

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic push

2574

#pragma GCC diagnostic ignored "-Wcast-qual"

2575

#endif

2576

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

2577

#ifdef __GNUC__

2578

#pragma GCC diagnostic pop

2579

#endif

2580

2385

free(mc.current_server);

2581

2386

mc.current_server = next;

2582

2387

}

2583

2388

}

2584

2389

2585

/* Re-raise privileges */

2390

/* Re-raise priviliges */

2586

2391

{

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2614

}

2615

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

2619

perror_plus("Failed to lower privileges permanently");

2620

}

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();

2621

2417

}

2622

2418

2623

2419

free(interfaces_to_take_down);

2624

2420

free(interfaces_hooks);

2625

2421

2626

2422

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

2627

if(tempdir != NULL){

2423

if(tempdir_created){

2628

2424

struct dirent **direntries = NULL;

2629

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

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

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

2639

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

2640

alphasort);

2641

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

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

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

2649

if(ret == -1){

2650

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

2651

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

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

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);

2666

2444

}

2667

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");

2668

2455

}

2669

2456

}

2670

2457