/mandos/trunk : revision 599

9

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

10

*

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* 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 /* 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() */

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42

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

43

stdout, ferror() */

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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,

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inet_pton(), connect(),

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getnameinfo() */

60

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

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inet_pton(), connect() */

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

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60

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

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61

*/

63

62

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

73

72

*/

74

73

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

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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

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

80

78

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

81

79

argp_state, struct argp,

93

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argz_delete(), argz_append(),

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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;

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int hookdir_fd = -1;

146

141

uid_t uid = 65534;

147

142

gid_t gid = 65534;

148

143

159

154

160

155

/* Used for passing in values through the Avahi callback functions */

161

156

typedef struct {

157

AvahiSimplePoll *simple_poll;

162

158

AvahiServer *server;

163

159

gnutls_certificate_credentials_t cred;

164

160

unsigned int dh_bits;

166

162

const char *priority;

167

163

gpgme_ctx_t ctx;

168

164

server *current_server;

169

char *interfaces;

170

size_t interfaces_size;

171

165

} mandos_context;

172

166

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

167

/* global context so signal handler can reach it*/

168

mandos_context mc = { .simple_poll = NULL, .server = NULL,

169

.dh_bits = 1024, .priority = "SECURE256"

170

":!CTYPE-X.509:+CTYPE-OPENPGP",

171

.current_server = NULL };

175

172

176

173

sig_atomic_t quit_now = 0;

177

174

int signal_received = 0;

185

182

perror(print_text);

186

183

}

187

184

188

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

185

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

189

186

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

190

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va_list ap;

191

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va_start (ap, format);

192

189

193

190

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

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191

program_invocation_short_name));

195

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

192

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

196

193

}

197

194

198

195

/*

200

197

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

201

198

* "buffer_length" is how much is already used.

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199

*/

203

__attribute__((nonnull, warn_unused_result))

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200

size_t incbuffer(char **buffer, size_t buffer_length,

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201

size_t buffer_capacity){

206

202

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;

203

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

204

if(buffer == NULL){

213

205

return 0;

214

206

}

215

*buffer = new_buf;

216

207

buffer_capacity += BUFFER_SIZE;

217

208

}

218

209

return buffer_capacity;

219

210

}

220

211

221

212

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

222

__attribute__((nonnull, warn_unused_result))

223

213

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

224

int af, server **current_server){

214

int af){

225

215

int ret;

226

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

227

217

if(new_server == NULL){

234

224

.af = af };

235

225

if(new_server->ip == NULL){

236

226

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

227

return false;

253

228

}

254

229

/* Special case of first server */

255

if(*current_server == NULL){

230

if (mc.current_server == NULL){

256

231

new_server->next = new_server;

257

232

new_server->prev = new_server;

258

*current_server = new_server;

233

mc.current_server = new_server;

234

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

259

235

} else {

260

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

261

new_server->next = *current_server;

262

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

236

new_server->next = mc.current_server;

237

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

263

238

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

239

mc.current_server->prev = new_server;

240

}

241

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

242

if(ret == -1){

243

perror_plus("clock_gettime");

244

return false;

265

245

}

266

246

return true;

267

247

}

269

249

/*

270

250

* Initialize GPGME.

271

251

*/

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){

252

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

253

const char *tempdir){

277

254

gpgme_error_t rc;

278

255

gpgme_engine_info_t engine_info;

279

256

257

280

258

/*

281

259

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

282

260

*/

283

bool import_key(const char * const filename){

261

bool import_key(const char *filename){

284

262

int ret;

285

263

int fd;

286

264

gpgme_data_t pgp_data;

298

276

return false;

299

277

}

300

278

301

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

279

rc = gpgme_op_import(mc.ctx, pgp_data);

302

280

if(rc != GPG_ERR_NO_ERROR){

303

281

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

304

282

gpgme_strsource(rc), gpgme_strerror(rc));

348

326

}

349

327

350

328

/* Create new GPGME "context" */

351

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

329

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

352

330

if(rc != GPG_ERR_NO_ERROR){

353

331

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

354

332

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

367

345

* Decrypt OpenPGP data.

368

346

* Returns -1 on error

369

347

*/

370

__attribute__((nonnull, warn_unused_result))

371

348

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

349

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

350

char **plaintext){

375

351

gpgme_data_t dh_crypto, dh_plain;

376

352

gpgme_error_t rc;

377

353

ssize_t ret;

403

379

404

380

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

405

381

data buffer */

406

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

382

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

407

383

if(rc != GPG_ERR_NO_ERROR){

408

384

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

409

385

gpgme_strsource(rc), gpgme_strerror(rc));

410

386

plaintext_length = -1;

411

387

if(debug){

412

388

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

389

result = gpgme_op_decrypt_result(mc.ctx);

414

390

if(result == NULL){

415

391

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

416

392

} else {

493

469

return plaintext_length;

494

470

}

495

471

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

472

static const char * safer_gnutls_strerror(int value){

498

473

const char *ret = gnutls_strerror(value);

499

474

if(ret == NULL)

500

475

ret = "(unknown)";

502

477

}

503

478

504

479

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

480

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

507

481

const char* string){

508

482

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

509

483

}

510

484

511

__attribute__((nonnull, warn_unused_result))

512

485

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

486

const char *seckeyfilename){

515

487

int ret;

516

488

517

489

if(debug){

534

506

}

535

507

536

508

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

509

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

510

if(ret != GNUTLS_E_SUCCESS){

539

511

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

540

512

safer_gnutls_strerror(ret));

550

522

}

551

523

552

524

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

525

(mc.cred, pubkeyfilename, seckeyfilename,

554

526

GNUTLS_OPENPGP_FMT_BASE64);

555

527

if(ret != GNUTLS_E_SUCCESS){

556

528

fprintf_plus(stderr,

562

534

}

563

535

564

536

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

537

ret = gnutls_dh_params_init(&mc.dh_params);

566

538

if(ret != GNUTLS_E_SUCCESS){

567

539

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

540

" initialization: %s\n",

569

541

safer_gnutls_strerror(ret));

570

542

goto globalfail;

571

543

}

572

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

544

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

573

545

if(ret != GNUTLS_E_SUCCESS){

574

546

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

575

547

safer_gnutls_strerror(ret));

576

548

goto globalfail;

577

549

}

578

550

579

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

551

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

552

581

553

return 0;

582

554

583

555

globalfail:

584

556

585

gnutls_certificate_free_credentials(mc->cred);

557

gnutls_certificate_free_credentials(mc.cred);

586

558

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

559

gnutls_dh_params_deinit(mc.dh_params);

588

560

return -1;

589

561

}

590

562

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

563

static int init_gnutls_session(gnutls_session_t *session){

594

564

int ret;

595

565

/* GnuTLS session creation */

596

566

do {

608

578

{

609

579

const char *err;

610

580

do {

611

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

581

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

612

582

if(quit_now){

613

583

gnutls_deinit(*session);

614

584

return -1;

625

595

626

596

do {

627

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

598

mc.cred);

629

599

if(quit_now){

630

600

gnutls_deinit(*session);

631

601

return -1;

641

611

/* ignore client certificate if any. */

642

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

613

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

615

646

616

return 0;

647

617

}

651

621

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

652

622

653

623

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

655

624

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

656

625

AvahiIfIndex if_index,

657

int af, mandos_context *mc){

626

int af){

658

627

int ret, tcp_sd = -1;

659

628

ssize_t sret;

660

struct sockaddr_storage to;

629

union {

630

struct sockaddr_in in;

631

struct sockaddr_in6 in6;

632

} to;

661

633

char *buffer = NULL;

662

634

char *decrypted_buffer = NULL;

663

635

size_t buffer_length = 0;

687

659

return -1;

688

660

}

689

661

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);

662

ret = init_gnutls_session(&session);

723

663

if(ret != 0){

724

664

return -1;

725

665

}

744

684

745

685

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

746

686

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);

687

to.in6.sin6_family = (sa_family_t)af;

688

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

749

689

} 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);

690

to.in.sin_family = (sa_family_t)af;

691

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

752

692

}

753

693

if(ret < 0 ){

754

694

int e = errno;

763

703

goto mandos_end;

764

704

}

765

705

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)){

706

to.in6.sin6_port = htons(port);

707

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

708

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

709

-Wunreachable-code*/

769

710

if(if_index == AVAHI_IF_UNSPEC){

770

711

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

771

712

" incomplete without a network interface\n");

773

714

goto mandos_end;

774

715

}

775

716

/* Set the network interface number as scope */

776

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

717

to.in6.sin6_scope_id = (uint32_t)if_index;

777

718

}

778

719

} else {

779

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

720

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

721

-Wconversion and

722

-Wunreachable-code */

780

723

}

781

724

782

725

if(quit_now){

799

742

}

800

743

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

801

744

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

745

const char *pcret;

802

746

if(af == AF_INET6){

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

747

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

748

sizeof(addrstr));

807

749

} else {

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

750

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

751

sizeof(addrstr));

812

752

}

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);

753

if(pcret == NULL){

754

perror_plus("inet_ntop");

755

} else {

756

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

757

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

758

}

819

759

}

820

760

}

821

761

825

765

}

826

766

827

767

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

768

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

830

769

} else {

831

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

832

sizeof(struct sockaddr_in));

770

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

833

771

}

834

772

if(ret < 0){

835

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

773

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

836

774

int e = errno;

837

775

perror_plus("connect");

838

776

errno = e;

999

937

if(buffer_length > 0){

1000

938

ssize_t decrypted_buffer_size;

1001

939

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1002

&decrypted_buffer, mc);

940

&decrypted_buffer);

1003

941

if(decrypted_buffer_size >= 0){

1004

942

1005

943

written = 0;

1053

991

return retval;

1054

992

}

1055

993

1056

__attribute__((nonnull))

1057

994

static void resolve_callback(AvahiSServiceResolver *r,

1058

995

AvahiIfIndex interface,

1059

996

AvahiProtocol proto,

1067

1004

AVAHI_GCC_UNUSED AvahiStringList *txt,

1068

1005

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1069

1006

flags,

1070

void *mc){

1007

AVAHI_GCC_UNUSED void* userdata){

1071

1008

if(r == NULL){

1072

1009

return;

1073

1010

}

1085

1022

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

1086

1023

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

1087

1024

domain,

1088

avahi_strerror(avahi_server_errno

1089

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

1025

avahi_strerror(avahi_server_errno(mc.server)));

1090

1026

break;

1091

1027

1092

1028

case AVAHI_RESOLVER_FOUND:

1100

1036

}

1101

1037

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

1102

1038

interface,

1103

avahi_proto_to_af(proto),

1104

mc);

1039

avahi_proto_to_af(proto));

1105

1040

if(ret == 0){

1106

avahi_simple_poll_quit(simple_poll);

1041

avahi_simple_poll_quit(mc.simple_poll);

1107

1042

} else {

1108

1043

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

1109

avahi_proto_to_af(proto),

1110

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

1044

avahi_proto_to_af(proto))){

1111

1045

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

1112

1046

" list\n", name);

1113

1047

}

1126

1060

const char *domain,

1127

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1128

1062

flags,

1129

void *mc){

1063

AVAHI_GCC_UNUSED void* userdata){

1130

1064

if(b == NULL){

1131

1065

return;

1132

1066

}

1143

1077

case AVAHI_BROWSER_FAILURE:

1144

1078

1145

1079

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

1146

avahi_strerror(avahi_server_errno

1147

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

1148

avahi_simple_poll_quit(simple_poll);

1080

avahi_strerror(avahi_server_errno(mc.server)));

1081

avahi_simple_poll_quit(mc.simple_poll);

1149

1082

return;

1150

1083

1151

1084

case AVAHI_BROWSER_NEW:

1154

1087

the callback function is called the Avahi server will free the

1155

1088

resolver for us. */

1156

1089

1157

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

1158

interface, protocol, name, type,

1159

domain, protocol, 0,

1160

resolve_callback, mc) == NULL)

1090

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

1091

name, type, domain, protocol, 0,

1092

resolve_callback, NULL) == NULL)

1161

1093

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

1162

1094

" %s\n", name,

1163

avahi_strerror(avahi_server_errno

1164

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

1095

avahi_strerror(avahi_server_errno(mc.server)));

1165

1096

break;

1166

1097

1167

1098

case AVAHI_BROWSER_REMOVE:

1186

1117

signal_received = sig;

1187

1118

int old_errno = errno;

1188

1119

/* set main loop to exit */

1189

if(simple_poll != NULL){

1190

avahi_simple_poll_quit(simple_poll);

1120

if(mc.simple_poll != NULL){

1121

avahi_simple_poll_quit(mc.simple_poll);

1191

1122

}

1192

1123

errno = old_errno;

1193

1124

}

1194

1125

1195

__attribute__((nonnull, warn_unused_result))

1196

1126

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

1197

1127

int ret;

1198

1128

error_t ret_errno;

1217

1147

return true;

1218

1148

}

1219

1149

1220

__attribute__((nonnull, warn_unused_result))

1221

1150

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

1222

1151

1223

1152

/* Reject the loopback device */

1265

1194

* corresponds to an acceptable network device.

1266

1195

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

1267

1196

*/

1268

__attribute__((nonnull, warn_unused_result))

1269

1197

int good_interface(const struct dirent *if_entry){

1270

1198

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

1271

1199

return 0;

1289

1217

/*

1290

1218

* This function determines if a network interface is up.

1291

1219

*/

1292

__attribute__((nonnull, warn_unused_result))

1293

1220

bool interface_is_up(const char *interface){

1294

1221

struct ifreq ifr;

1295

1222

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

1306

1233

/*

1307

1234

* This function determines if a network interface is running

1308

1235

*/

1309

__attribute__((nonnull, warn_unused_result))

1310

1236

bool interface_is_running(const char *interface){

1311

1237

struct ifreq ifr;

1312

1238

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

1320

1246

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

1321

1247

}

1322

1248

1323

__attribute__((nonnull, pure, warn_unused_result))

1324

1249

int notdotentries(const struct dirent *direntry){

1325

1250

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

1326

1251

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

1333

1258

}

1334

1259

1335

1260

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

1336

__attribute__((nonnull, warn_unused_result))

1337

1261

int runnable_hook(const struct dirent *direntry){

1338

1262

int ret;

1339

1263

size_t sret;

1347

1271

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

1348

1272

"abcdefghijklmnopqrstuvwxyz"

1349

1273

"0123456789"

1350

"_.-");

1274

"_-");

1351

1275

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

1352

1276

/* Contains non-allowed characters */

1353

1277

if(debug){

1357

1281

return 0;

1358

1282

}

1359

1283

1360

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

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1361

1292

if(ret == -1){

1362

1293

if(debug){

1363

1294

perror_plus("Could not stat hook");

1387

1318

return 1;

1388

1319

}

1389

1320

1390

__attribute__((nonnull, warn_unused_result))

1391

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1392

mandos_context *mc){

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1393

1322

int ret;

1394

1323

struct timespec now;

1395

1324

struct timespec waited_time;

1396

1325

intmax_t block_time;

1397

1326

1398

1327

while(true){

1399

if(mc->current_server == NULL){

1400

if(debug){

1328

if(mc.current_server == NULL){

1329

if (debug){

1401

1330

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

1402

1331

" No timeout!\n");

1403

1332

}

1404

1333

ret = avahi_simple_poll_iterate(s, -1);

1405

1334

} else {

1406

if(debug){

1335

if (debug){

1407

1336

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

1408

1337

" it, or wait\n");

1409

1338

}

1416

1345

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

1417

1346

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

1418

1347

waited_time.tv_sec = (now.tv_sec

1419

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

1348

- mc.current_server->last_seen.tv_sec);

1420

1349

waited_time.tv_nsec = (now.tv_nsec

1421

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

1350

- mc.current_server->last_seen.tv_nsec);

1422

1351

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

1423

1352

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

1424

1353

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

1426

1355

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

1427

1356

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

1428

1357

1429

if(debug){

1358

if (debug){

1430

1359

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

1431

1360

block_time);

1432

1361

}

1433

1362

1434

1363

if(block_time <= 0){

1435

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

1436

mc->current_server->port,

1437

mc->current_server->if_index,

1438

mc->current_server->af, mc);

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

1439

1368

if(ret == 0){

1440

avahi_simple_poll_quit(s);

1369

avahi_simple_poll_quit(mc.simple_poll);

1441

1370

return 0;

1442

1371

}

1443

1372

ret = clock_gettime(CLOCK_MONOTONIC,

1444

&mc->current_server->last_seen);

1373

&mc.current_server->last_seen);

1445

1374

if(ret == -1){

1446

1375

perror_plus("clock_gettime");

1447

1376

return -1;

1448

1377

}

1449

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

1378

mc.current_server = mc.current_server->next;

1450

1379

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

1451

1380

servers, but don't block */

1452

1381

}

1454

1383

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

1455

1384

}

1456

1385

if(ret != 0){

1457

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

1386

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

1458

1387

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

1459

1388

}

1460

1389

}

1462

1391

}

1463

1392

1464

1393

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

1465

__attribute__((warn_unused_result))

1466

1394

error_t raise_privileges(void){

1467

1395

error_t old_errno = errno;

1468

1396

error_t ret_errno = 0;

1469

1397

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

1470

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1471

1400

}

1472

1401

errno = old_errno;

1473

1402

return ret_errno;

1474

1403

}

1475

1404

1476

1405

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

1477

__attribute__((warn_unused_result))

1478

1406

error_t raise_privileges_permanently(void){

1479

1407

error_t old_errno = errno;

1480

1408

error_t ret_errno = raise_privileges();

1484

1412

}

1485

1413

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

1486

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1487

1416

}

1488

1417

errno = old_errno;

1489

1418

return ret_errno;

1490

1419

}

1491

1420

1492

1421

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

1493

__attribute__((warn_unused_result))

1494

1422

error_t lower_privileges(void){

1495

1423

error_t old_errno = errno;

1496

1424

error_t ret_errno = 0;

1497

1425

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

1498

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1499

1428

}

1500

1429

errno = old_errno;

1501

1430

return ret_errno;

1502

1431

}

1503

1432

1504

1433

/* Lower privileges permanently */

1505

__attribute__((warn_unused_result))

1506

1434

error_t lower_privileges_permanently(void){

1507

1435

error_t old_errno = errno;

1508

1436

error_t ret_errno = 0;

1509

1437

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

1510

1438

ret_errno = errno;

1439

perror_plus("setuid");

1511

1440

}

1512

1441

errno = old_errno;

1513

1442

return ret_errno;

1514

1443

}

1515

1444

1516

__attribute__((nonnull))

1517

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

1445

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

1518

1446

const float delay){

1519

struct dirent **direntries = NULL;

1520

if(hookdir_fd == -1){

1521

hookdir_fd = open(hookdir, O_RDONLY);

1522

if(hookdir_fd == -1){

1523

if(errno == ENOENT){

1524

if(debug){

1525

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

1526

" found\n", hookdir);

1527

}

1528

} else {

1529

perror_plus("open");

1530

}

1531

return;

1532

}

1533

}

1534

#ifdef __GLIBC__

1535

#if __GLIBC_PREREQ(2, 15)

1536

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

1537

runnable_hook, alphasort);

1538

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

1539

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

1540

alphasort);

1541

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

1542

#else /* not __GLIBC__ */

1543

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

1544

alphasort);

1545

#endif /* not __GLIBC__ */

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1546

1452

if(numhooks == -1){

1547

perror_plus("scandir");

1548

return;

1549

}

1550

struct dirent *direntry;

1551

int ret;

1552

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

1553

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

1554

direntry = direntries[i];

1555

if(debug){

1556

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

1557

direntry->d_name);

1453

if(errno == ENOENT){

1454

if(debug){

1455

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

1456

" found\n", hookdir);

1457

}

1458

} else {

1459

perror_plus("scandir");

1558

1460

}

1559

pid_t hook_pid = fork();

1560

if(hook_pid == 0){

1561

/* Child */

1562

/* Raise privileges */

1563

errno = raise_privileges_permanently();

1564

if(errno != 0){

1565

perror_plus("Failed to raise privileges");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Set group */

1569

errno = 0;

1570

ret = setgid(0);

1571

if(ret == -1){

1572

perror_plus("setgid");

1573

_exit(EX_NOPERM);

1574

}

1575

/* Reset supplementary groups */

1576

errno = 0;

1577

ret = setgroups(0, NULL);

1578

if(ret == -1){

1579

perror_plus("setgroups");

1580

_exit(EX_NOPERM);

1581

}

1582

ret = dup2(devnull, STDIN_FILENO);

1583

if(ret == -1){

1584

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

1585

_exit(EX_OSERR);

1586

}

1587

ret = close(devnull);

1588

if(ret == -1){

1589

perror_plus("close");

1590

_exit(EX_OSERR);

1591

}

1592

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1593

if(ret == -1){

1594

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

1595

_exit(EX_OSERR);

1596

}

1597

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

1598

if(ret == -1){

1599

perror_plus("setenv");

1600

_exit(EX_OSERR);

1601

}

1602

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

1603

if(ret == -1){

1604

perror_plus("setenv");

1605

_exit(EX_OSERR);

1606

}

1607

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

1608

if(ret == -1){

1609

perror_plus("setenv");

1610

_exit(EX_OSERR);

1611

}

1612

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

1613

if(ret == -1){

1614

perror_plus("setenv");

1615

_exit(EX_OSERR);

1616

}

1617

char *delaystring;

1618

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

1619

if(ret == -1){

1461

} else {

1462

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

1463

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

1464

direntry = direntries[i];

1465

char *fullname = NULL;

1466

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

1467

if(ret < 0){

1620

1468

perror_plus("asprintf");

1621

_exit(EX_OSERR);

1622

}

1623

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

1624

if(ret == -1){

1469

continue;

1470

}

1471

if(debug){

1472

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

1473

direntry->d_name);

1474

}

1475

pid_t hook_pid = fork();

1476

if(hook_pid == 0){

1477

/* Child */

1478

/* Raise privileges */

1479

raise_privileges_permanently();

1480

/* Set group */

1481

errno = 0;

1482

ret = setgid(0);

1483

if(ret == -1){

1484

perror_plus("setgid");

1485

}

1486

/* Reset supplementary groups */

1487

errno = 0;

1488

ret = setgroups(0, NULL);

1489

if(ret == -1){

1490

perror_plus("setgroups");

1491

}

1492

dup2(devnull, STDIN_FILENO);

1493

close(devnull);

1494

dup2(STDERR_FILENO, STDOUT_FILENO);

1495

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

1496

if(ret == -1){

1497

perror_plus("setenv");

1498

_exit(EX_OSERR);

1499

}

1500

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

1501

if(ret == -1){

1502

perror_plus("setenv");

1503

_exit(EX_OSERR);

1504

}

1505

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

1506

if(ret == -1){

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

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

1511

if(ret == -1){

1512

perror_plus("setenv");

1513

_exit(EX_OSERR);

1514

}

1515

char *delaystring;

1516

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

1517

if(ret == -1){

1518

perror_plus("asprintf");

1519

_exit(EX_OSERR);

1520

}

1521

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

1522

if(ret == -1){

1523

free(delaystring);

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1625

1527

free(delaystring);

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

free(delaystring);

1630

if(connect_to != NULL){

1631

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

1632

if(ret == -1){

1633

perror_plus("setenv");

1634

_exit(EX_OSERR);

1635

}

1636

}

1637

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

1638

if(hook_fd == -1){

1639

perror_plus("openat");

1640

_exit(EXIT_FAILURE);

1641

}

1642

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

1643

perror_plus("close");

1644

_exit(EXIT_FAILURE);

1645

}

1646

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

1647

environ) == -1){

1648

perror_plus("fexecve");

1649

_exit(EXIT_FAILURE);

1650

}

1651

} else {

1652

int status;

1653

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

1654

perror_plus("waitpid");

1655

continue;

1656

}

1657

if(WIFEXITED(status)){

1658

if(WEXITSTATUS(status) != 0){

1659

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

1660

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

1661

WEXITSTATUS(status));

1662

continue;

1663

}

1664

} else if(WIFSIGNALED(status)){

1665

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

1666

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

1667

WTERMSIG(status));

1668

continue;

1528

if(connect_to != NULL){

1529

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

1530

if(ret == -1){

1531

perror_plus("setenv");

1532

_exit(EX_OSERR);

1533

}

1534

}

1535

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

1536

perror_plus("execl");

1537

_exit(EXIT_FAILURE);

1538

}

1669

1539

} else {

1670

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

1671

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

1672

continue;

1673

}

1674

}

1675

if(debug){

1676

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

1677

direntry->d_name);

1678

}

1679

}

1680

free(direntries);

1681

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

1682

perror_plus("close");

1683

} else {

1684

hookdir_fd = -1;

1685

}

1686

close(devnull);

1540

int status;

1541

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

1542

perror_plus("waitpid");

1543

free(fullname);

1544

continue;

1545

}

1546

if(WIFEXITED(status)){

1547

if(WEXITSTATUS(status) != 0){

1548

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

1549

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

1550

WEXITSTATUS(status));

1551

free(fullname);

1552

continue;

1553

}

1554

} else if(WIFSIGNALED(status)){

1555

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

1556

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

1557

WTERMSIG(status));

1558

free(fullname);

1559

continue;

1560

} else {

1561

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

1562

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

1563

free(fullname);

1564

continue;

1565

}

1566

}

1567

free(fullname);

1568

if(debug){

1569

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

1570

direntry->d_name);

1571

}

1572

}

1573

close(devnull);

1574

}

1575

return true;

1687

1576

}

1688

1577

1689

__attribute__((nonnull, warn_unused_result))

1690

1578

error_t bring_up_interface(const char *const interface,

1691

1579

const float delay){

1580

int sd = -1;

1692

1581

error_t old_errno = errno;

1693

int ret;

1582

error_t ret_errno = 0;

1583

int ret, ret_setflags;

1694

1584

struct ifreq network;

1695

1585

unsigned int if_index = if_nametoindex(interface);

1696

1586

if(if_index == 0){

1705

1595

}

1706

1596

1707

1597

if(not interface_is_up(interface)){

1708

error_t ret_errno = 0, ioctl_errno = 0;

1709

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

1598

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

1710

1599

ret_errno = errno;

1711

1600

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

1712

1601

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

1713

errno = old_errno;

1714

1602

return ret_errno;

1715

1603

}

1716

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

1604

network.ifr_flags |= IFF_UP;

1717

1605

1718

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

1719

if(sd == -1){

1606

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1607

if(sd < 0){

1720

1608

ret_errno = errno;

1721

1609

perror_plus("socket");

1722

1610

errno = old_errno;

1723

1611

return ret_errno;

1724

1612

}

1725

1613

1726

1614

if(quit_now){

1727

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

1728

if(ret == -1){

1729

perror_plus("close");

1730

}

1615

close(sd);

1731

1616

errno = old_errno;

1732

1617

return EINTR;

1733

1618

}

1737

1622

interface);

1738

1623

}

1739

1624

1740

/* Raise privileges */

1741

ret_errno = raise_privileges();

1742

if(ret_errno != 0){

1743

errno = ret_errno;

1744

perror_plus("Failed to raise privileges");

1745

}

1625

/* Raise priviliges */

1626

raise_privileges();

1746

1627

1747

1628

#ifdef __linux__

1748

int ret_linux;

1749

bool restore_loglevel = false;

1750

if(ret_errno == 0){

1751

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1752

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

1753

ret_linux = klogctl(8, NULL, 5);

1754

if(ret_linux == -1){

1755

perror_plus("klogctl");

1756

} else {

1757

restore_loglevel = true;

1758

}

1629

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1630

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

1631

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

1632

bool restore_loglevel = true;

1633

if(ret_linux == -1){

1634

restore_loglevel = false;

1635

perror_plus("klogctl");

1759

1636

}

1760

1637

#endif /* __linux__ */

1761

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

1762

ioctl_errno = errno;

1638

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

1639

ret_errno = errno;

1763

1640

#ifdef __linux__

1764

1641

if(restore_loglevel){

1765

1642

ret_linux = klogctl(7, NULL, 0);

1769

1646

}

1770

1647

#endif /* __linux__ */

1771

1648

1772

/* If raise_privileges() succeeded above */

1773

if(ret_errno == 0){

1774

/* Lower privileges */

1775

ret_errno = lower_privileges();

1776

if(ret_errno != 0){

1777

errno = ret_errno;

1778

perror_plus("Failed to lower privileges");

1779

}

1780

}

1649

/* Lower privileges */

1650

lower_privileges();

1781

1651

1782

1652

/* Close the socket */

1783

1653

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

1786

1656

}

1787

1657

1788

1658

if(ret_setflags == -1){

1789

errno = ioctl_errno;

1659

errno = ret_errno;

1790

1660

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1791

1661

errno = old_errno;

1792

return ioctl_errno;

1662

return ret_errno;

1793

1663

}

1794

1664

} else if(debug){

1795

1665

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

1813

1683

return 0;

1814

1684

}

1815

1685

1816

__attribute__((nonnull, warn_unused_result))

1817

1686

error_t take_down_interface(const char *const interface){

1687

int sd = -1;

1818

1688

error_t old_errno = errno;

1689

error_t ret_errno = 0;

1690

int ret, ret_setflags;

1819

1691

struct ifreq network;

1820

1692

unsigned int if_index = if_nametoindex(interface);

1821

1693

if(if_index == 0){

1824

1696

return ENXIO;

1825

1697

}

1826

1698

if(interface_is_up(interface)){

1827

error_t ret_errno = 0, ioctl_errno = 0;

1828

1699

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

1829

1700

ret_errno = errno;

1830

1701

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

1831

1702

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

1832

errno = old_errno;

1833

1703

return ret_errno;

1834

1704

}

1835

1705

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

1836

1706

1837

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

1838

if(sd == -1){

1707

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1708

if(sd < 0){

1839

1709

ret_errno = errno;

1840

1710

perror_plus("socket");

1841

1711

errno = old_errno;

1847

1717

interface);

1848

1718

}

1849

1719

1850

/* Raise privileges */

1851

ret_errno = raise_privileges();

1852

if(ret_errno != 0){

1853

errno = ret_errno;

1854

perror_plus("Failed to raise privileges");

1855

}

1856

1857

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

1858

ioctl_errno = errno;

1859

1860

/* If raise_privileges() succeeded above */

1861

if(ret_errno == 0){

1862

/* Lower privileges */

1863

ret_errno = lower_privileges();

1864

if(ret_errno != 0){

1865

errno = ret_errno;

1866

perror_plus("Failed to lower privileges");

1867

}

1868

}

1720

/* Raise priviliges */

1721

raise_privileges();

1722

1723

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

1724

ret_errno = errno;

1725

1726

/* Lower privileges */

1727

lower_privileges();

1869

1728

1870

1729

/* Close the socket */

1871

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

1730

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

1872

1731

if(ret == -1){

1873

1732

perror_plus("close");

1874

1733

}

1875

1734

1876

1735

if(ret_setflags == -1){

1877

errno = ioctl_errno;

1736

errno = ret_errno;

1878

1737

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1879

1738

errno = old_errno;

1880

return ioctl_errno;

1739

return ret_errno;

1881

1740

}

1882

1741

} else if(debug){

1883

1742

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

1889

1748

}

1890

1749

1891

1750

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

1892

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

1893

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

1894

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

1895

.interfaces = NULL, .interfaces_size = 0 };

1896

1751

AvahiSServiceBrowser *sb = NULL;

1897

1752

error_t ret_errno;

1898

1753

int ret;

1899

1754

intmax_t tmpmax;

1900

1755

char *tmp;

1901

1756

int exitcode = EXIT_SUCCESS;

1757

char *interfaces = NULL;

1758

size_t interfaces_size = 0;

1902

1759

char *interfaces_to_take_down = NULL;

1903

1760

size_t interfaces_to_take_down_size = 0;

1904

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

1905

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

1906

char *tempdir = NULL;

1761

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

1762

bool tempdir_created = false;

1907

1763

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1908

1764

const char *seckey = PATHDIR "/" SECKEY;

1909

1765

const char *pubkey = PATHDIR "/" PUBKEY;

1910

1766

char *interfaces_hooks = NULL;

1767

size_t interfaces_hooks_size = 0;

1911

1768

1912

1769

bool gnutls_initialized = false;

1913

1770

bool gpgme_initialized = false;

2004

1861

connect_to = arg;

2005

1862

break;

2006

1863

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

2007

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

2008

arg, (int)',');

1864

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

1865

(int)',');

2009

1866

if(ret_errno != 0){

2010

1867

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

2011

1868

}

2091

1948

/* Work around Debian bug #633582:

2092

1949

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

2093

1950

2094

/* Re-raise privileges */

2095

ret_errno = raise_privileges();

2096

if(ret_errno != 0){

2097

errno = ret_errno;

2098

perror_plus("Failed to raise privileges");

2099

} else {

1951

/* Re-raise priviliges */

1952

if(raise_privileges() == 0){

2100

1953

struct stat st;

2101

1954

2102

1955

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

2142

1995

}

2143

1996

2144

1997

/* Lower privileges */

2145

ret_errno = lower_privileges();

2146

if(ret_errno != 0){

2147

errno = ret_errno;

2148

perror_plus("Failed to lower privileges");

1998

errno = 0;

1999

ret = seteuid(uid);

2000

if(ret == -1){

2001

perror_plus("seteuid");

2149

2002

}

2150

2003

}

2151

2004

}

2152

2005

2153

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

2006

/* Remove empty interface names */

2154

2007

{

2155

2008

char *interface = NULL;

2156

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

2009

while((interface = argz_next(interfaces, interfaces_size,

2157

2010

interface))){

2158

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

2159

and if_nametoindex(interface) == 0){

2160

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

2011

if(if_nametoindex(interface) == 0){

2012

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

2161

2013

fprintf_plus(stderr, "Not using nonexisting interface"

2162

2014

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

2163

2015

}

2164

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

2016

argz_delete(&interfaces, &interfaces_size, interface);

2165

2017

interface = NULL;

2166

2018

}

2167

2019

}

2169

2021

2170

2022

/* Run network hooks */

2171

2023

{

2172

if(mc.interfaces != NULL){

2173

interfaces_hooks = malloc(mc.interfaces_size);

2024

2025

if(interfaces != NULL){

2026

interfaces_hooks = malloc(interfaces_size);

2174

2027

if(interfaces_hooks == NULL){

2175

2028

perror_plus("malloc");

2176

2029

goto end;

2177

2030

}

2178

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

2179

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

2180

}

2181

run_network_hooks("start", interfaces_hooks != NULL ?

2182

interfaces_hooks : "", delay);

2031

memcpy(interfaces_hooks, interfaces, interfaces_size);

2032

interfaces_hooks_size = interfaces_size;

2033

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2034

(int)',');

2035

}

2036

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

2037

interfaces_hooks : "", delay)){

2038

goto end;

2039

}

2183

2040

}

2184

2041

2185

2042

if(not debug){

2190

2047

from the signal handler */

2191

2048

/* Initialize the pseudo-RNG for Avahi */

2192

2049

srand((unsigned int) time(NULL));

2193

simple_poll = avahi_simple_poll_new();

2194

if(simple_poll == NULL){

2050

mc.simple_poll = avahi_simple_poll_new();

2051

if(mc.simple_poll == NULL){

2195

2052

fprintf_plus(stderr,

2196

2053

"Avahi: Failed to create simple poll object.\n");

2197

2054

exitcode = EX_UNAVAILABLE;

2262

2119

}

2263

2120

2264

2121

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

2265

if(mc.interfaces == NULL){

2266

struct dirent **direntries = NULL;

2122

if(interfaces == NULL){

2123

struct dirent **direntries;

2267

2124

/* Look for any good interfaces */

2268

2125

ret = scandir(sys_class_net, &direntries, good_interface,

2269

2126

alphasort);

2270

2127

if(ret >= 1){

2271

2128

/* Add all found interfaces to interfaces list */

2272

2129

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

2273

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

2130

ret_errno = argz_add(&interfaces, &interfaces_size,

2274

2131

direntries[i]->d_name);

2275

2132

if(ret_errno != 0){

2276

errno = ret_errno;

2277

2133

perror_plus("argz_add");

2278

2134

continue;

2279

2135

}

2284

2140

}

2285

2141

free(direntries);

2286

2142

} else {

2287

if(ret == 0){

2288

free(direntries);

2289

}

2143

free(direntries);

2290

2144

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

2291

2145

exitcode = EXIT_FAILURE;

2292

2146

goto end;

2293

2147

}

2294

2148

}

2295

2149

2296

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

2297

{

2150

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

2151

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

2152

if(debug){

2153

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

2154

interfaces);

2155

}

2156

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2157

}

2158

2159

/* Bring up interfaces which are down */

2160

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

2161

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

2298

2162

char *interface = NULL;

2299

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

2163

while((interface = argz_next(interfaces, interfaces_size,

2300

2164

interface))){

2301

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

2302

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

2303

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

2304

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

2305

interface);

2306

interface = NULL;

2307

while((interface = argz_next(mc.interfaces,

2308

mc.interfaces_size, interface))){

2309

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

2310

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

2311

interface);

2312

interface = NULL;

2313

}

2314

}

2315

break;

2316

}

2317

2165

bool interface_was_up = interface_is_up(interface);

2318

errno = bring_up_interface(interface, delay);

2166

ret = bring_up_interface(interface, delay);

2319

2167

if(not interface_was_up){

2320

if(errno != 0){

2168

if(ret != 0){

2169

errno = ret;

2321

2170

perror_plus("Failed to bring up interface");

2322

2171

} else {

2323

errno = argz_add(&interfaces_to_take_down,

2324

&interfaces_to_take_down_size,

2325

interface);

2326

if(errno != 0){

2327

perror_plus("argz_add");

2328

}

2172

ret_errno = argz_add(&interfaces_to_take_down,

2173

&interfaces_to_take_down_size,

2174

interface);

2329

2175

}

2330

2176

}

2331

2177

}

2178

free(interfaces);

2179

interfaces = NULL;

2180

interfaces_size = 0;

2332

2181

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

2333

2182

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

2334

2183

}

2335

2184

}

2336

2185

2337

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

2338

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

2339

if(debug){

2340

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

2341

mc.interfaces);

2342

}

2343

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

2344

}

2345

2346

2186

if(quit_now){

2347

2187

goto end;

2348

2188

}

2349

2189

2350

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

2190

ret = init_gnutls_global(pubkey, seckey);

2351

2191

if(ret == -1){

2352

2192

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

2353

2193

exitcode = EX_UNAVAILABLE;

2360

2200

goto end;

2361

2201

}

2362

2202

2363

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

2364

tempdir = mkdtemp(run_tempdir);

2365

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

2366

if(debug){

2367

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

2368

run_tempdir, old_tempdir);

2369

}

2370

tempdir = mkdtemp(old_tempdir);

2371

}

2372

if(tempdir == NULL){

2203

if(mkdtemp(tempdir) == NULL){

2373

2204

perror_plus("mkdtemp");

2374

2205

goto end;

2375

2206

}

2207

tempdir_created = true;

2376

2208

2377

2209

if(quit_now){

2378

2210

goto end;

2379

2211

}

2380

2212

2381

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

2213

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

2382

2214

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

2383

2215

exitcode = EX_UNAVAILABLE;

2384

2216

goto end;

2414

2246

exitcode = EX_USAGE;

2415

2247

goto end;

2416

2248

}

2417

2249

2418

2250

if(quit_now){

2419

2251

goto end;

2420

2252

}

2441

2273

}

2442

2274

2443

2275

while(not quit_now){

2444

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

2445

&mc);

2276

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

2446

2277

if(quit_now or ret == 0){

2447

2278

break;

2448

2279

}

2450

2281

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

2451

2282

(int)retry_interval);

2452

2283

}

2453

sleep((unsigned int)retry_interval);

2284

sleep((int)retry_interval);

2454

2285

}

2455

2286

2456

if(not quit_now){

2287

if (not quit_now){

2457

2288

exitcode = EXIT_SUCCESS;

2458

2289

}

2459

2290

2474

2305

config.publish_domain = 0;

2475

2306

2476

2307

/* Allocate a new server */

2477

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2478

&config, NULL, NULL, &ret_errno);

2308

mc.server = avahi_server_new(avahi_simple_poll_get

2309

(mc.simple_poll), &config, NULL,

2310

NULL, &ret_errno);

2479

2311

2480

2312

/* Free the Avahi configuration data */

2481

2313

avahi_server_config_free(&config);

2496

2328

/* Create the Avahi service browser */

2497

2329

sb = avahi_s_service_browser_new(mc.server, if_index,

2498

2330

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2499

NULL, 0, browse_callback,

2500

(void *)&mc);

2331

NULL, 0, browse_callback, NULL);

2501

2332

if(sb == NULL){

2502

2333

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

2503

2334

avahi_strerror(avahi_server_errno(mc.server)));

2514

2345

if(debug){

2515

2346

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

2516

2347

}

2517

2518

ret = avahi_loop_with_timeout(simple_poll,

2519

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

2348

2349

ret = avahi_loop_with_timeout(mc.simple_poll,

2350

(int)(retry_interval * 1000));

2520

2351

if(debug){

2521

2352

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

2522

2353

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

2529

2360

}

2530

2361

2531

2362

/* Cleanup things */

2532

free(mc.interfaces);

2533

2534

2363

if(sb != NULL)

2535

2364

avahi_s_service_browser_free(sb);

2536

2365

2537

2366

if(mc.server != NULL)

2538

2367

avahi_server_free(mc.server);

2539

2368

2540

if(simple_poll != NULL)

2541

avahi_simple_poll_free(simple_poll);

2369

if(mc.simple_poll != NULL)

2370

avahi_simple_poll_free(mc.simple_poll);

2542

2371

2543

2372

if(gnutls_initialized){

2544

2373

gnutls_certificate_free_credentials(mc.cred);

2556

2385

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

2557

2386

while(mc.current_server != NULL){

2558

2387

server *next = mc.current_server->next;

2559

#ifdef __GNUC__

2560

#pragma GCC diagnostic push

2561

#pragma GCC diagnostic ignored "-Wcast-qual"

2562

#endif

2563

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

2564

#ifdef __GNUC__

2565

#pragma GCC diagnostic pop

2566

#endif

2567

2388

free(mc.current_server);

2568

2389

mc.current_server = next;

2569

2390

}

2570

2391

}

2571

2392

2572

/* Re-raise privileges */

2393

/* Re-raise priviliges */

2573

2394

{

2574

ret_errno = raise_privileges();

2575

if(ret_errno != 0){

2576

errno = ret_errno;

2577

perror_plus("Failed to raise privileges");

2578

} else {

2579

2580

/* Run network hooks */

2581

run_network_hooks("stop", interfaces_hooks != NULL ?

2582

interfaces_hooks : "", delay);

2583

2584

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

2585

{

2586

char *interface = NULL;

2587

while((interface=argz_next(interfaces_to_take_down,

2588

interfaces_to_take_down_size,

2589

interface))){

2590

ret_errno = take_down_interface(interface);

2591

if(ret_errno != 0){

2592

errno = ret_errno;

2593

perror_plus("Failed to take down interface");

2594

}

2595

}

2596

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

2597

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

2598

" down\n");

2599

}

2600

}

2601

}

2602

2603

ret_errno = lower_privileges_permanently();

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to lower privileges permanently");

2607

}

2395

raise_privileges();

2396

2397

/* Run network hooks */

2398

run_network_hooks("stop", interfaces_hooks != NULL ?

2399

interfaces_hooks : "", delay);

2400

2401

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

2402

{

2403

char *interface = NULL;

2404

while((interface=argz_next(interfaces_to_take_down,

2405

interfaces_to_take_down_size,

2406

interface))){

2407

ret_errno = take_down_interface(interface);

2408

if(ret_errno != 0){

2409

errno = ret_errno;

2410

perror_plus("Failed to take down interface");

2411

}

2412

}

2413

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

2414

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

2415

" down\n");

2416

}

2417

}

2418

2419

lower_privileges_permanently();

2608

2420

}

2609

2421

2610

2422

free(interfaces_to_take_down);

2611

2423

free(interfaces_hooks);

2612

2424

2613

2425

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

2614

if(tempdir != NULL){

2426

if(tempdir_created){

2615

2427

struct dirent **direntries = NULL;

2616

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

2617

O_NOFOLLOW));

2618

if(tempdir_fd == -1){

2619

perror_plus("open");

2620

} else {

2621

#ifdef __GLIBC__

2622

#if __GLIBC_PREREQ(2, 15)

2623

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

2624

notdotentries, alphasort);

2625

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

2626

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

2627

alphasort);

2628

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

2629

#else /* not __GLIBC__ */

2630

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

2631

alphasort);

2632

#endif /* not __GLIBC__ */

2633

if(numentries >= 0){

2634

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

2635

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

2636

if(ret == -1){

2637

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

2638

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

2639

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

2640

}

2641

}

2642

2643

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

2644

free(direntries);

2645

if(numentries == -1){

2646

perror_plus("scandir");

2647

}

2648

ret = rmdir(tempdir);

2649

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

2650

perror_plus("rmdir");

2651

}

2428

struct dirent *direntry = NULL;

2429

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

2430

alphasort);

2431

if (numentries > 0){

2432

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

2433

direntry = direntries[i];

2434

char *fullname = NULL;

2435

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

2436

direntry->d_name);

2437

if(ret < 0){

2438

perror_plus("asprintf");

2439

continue;

2440

}

2441

ret = remove(fullname);

2442

if(ret == -1){

2443

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

2444

strerror(errno));

2445

}

2446

free(fullname);

2652

2447

}

2653

TEMP_FAILURE_RETRY(close(tempdir_fd));

2448

}

2449

2450

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

2451

free(direntries);

2452

if (numentries == -1){

2453

perror_plus("scandir");

2454

}

2455

ret = rmdir(tempdir);

2456

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

2457

perror_plus("rmdir");

2654

2458

}

2655

2459

}

2656

2460