/mandos/release : revision 237.17.8

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

41

42

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

43

stdout, ferror(), remove() */

44

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

44

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

45

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

46

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

47

strtof(), abort() */

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() */

58

inet_pton(), connect() */

60

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,

64

63

strtoimax() */

64

#include <assert.h> /* assert() */

65

#include <errno.h> /* perror(), errno,

66

program_invocation_short_name */

67

#include <time.h> /* nanosleep(), time(), sleep() */

74

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

75

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

76

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

77

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

77

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

78

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

79

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

80

argp_state, struct argp,

88

#include <sys/wait.h> /* waitpid(), WIFEXITED(),

89

WEXITSTATUS(), WTERMSIG() */

90

#include <grp.h> /* setgroups() */

91

#include <argz.h> /* argz_add_sep(), argz_next(),

92

argz_delete(), argz_append(),

93

argz_stringify(), argz_add(),

94

argz_count() */

95

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

96

EAI_SYSTEM, gai_strerror() */

97

91

98

92

#ifdef __linux__

99

93

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

141

135

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

142

136

char *connect_to = NULL;

143

137

const char *hookdir = HOOKDIR;

144

uid_t uid = 65534;

145

gid_t gid = 65534;

146

138

147

139

/* Doubly linked list that need to be circularly linked when used */

148

140

typedef struct server{

149

141

const char *ip;

150

in_port_t port;

142

uint16_t port;

151

143

AvahiIfIndex if_index;

152

144

int af;

153

145

struct timespec last_seen;

157

149

158

150

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

159

151

typedef struct {

152

AvahiSimplePoll *simple_poll;

160

153

AvahiServer *server;

161

154

gnutls_certificate_credentials_t cred;

162

155

unsigned int dh_bits;

164

157

const char *priority;

165

158

gpgme_ctx_t ctx;

166

159

server *current_server;

167

char *interfaces;

168

size_t interfaces_size;

169

160

} mandos_context;

170

161

171

/* global so signal handler can reach it*/

172

AvahiSimplePoll *simple_poll;

162

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

163

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

164

.dh_bits = 1024, .priority = "SECURE256"

165

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

166

.current_server = NULL };

173

167

174

168

sig_atomic_t quit_now = 0;

175

169

int signal_received = 0;

183

177

perror(print_text);

184

178

}

185

179

186

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

180

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

187

181

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

188

182

va_list ap;

189

183

va_start (ap, format);

190

184

191

185

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

192

186

program_invocation_short_name));

193

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

187

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

194

188

}

195

189

196

190

/*

198

192

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

199

193

* "buffer_length" is how much is already used.

200

194

*/

201

__attribute__((nonnull, warn_unused_result))

202

195

size_t incbuffer(char **buffer, size_t buffer_length,

203

196

size_t buffer_capacity){

204

197

if(buffer_length + BUFFER_SIZE > buffer_capacity){

205

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

206

if(new_buf == NULL){

207

int old_errno = errno;

208

free(*buffer);

209

errno = old_errno;

210

*buffer = NULL;

198

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

199

if(buffer == NULL){

211

200

return 0;

212

201

}

213

*buffer = new_buf;

214

202

buffer_capacity += BUFFER_SIZE;

215

203

}

216

204

return buffer_capacity;

217

205

}

218

206

219

207

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

220

__attribute__((nonnull, warn_unused_result))

221

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

222

int af, server **current_server){

208

bool add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,

209

int af){

223

210

int ret;

224

211

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

225

212

if(new_server == NULL){

234

221

perror_plus("strdup");

235

222

return false;

236

223

}

237

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

240

return false;

241

}

242

224

/* Special case of first server */

243

if(*current_server == NULL){

225

if (mc.current_server == NULL){

244

226

new_server->next = new_server;

245

227

new_server->prev = new_server;

246

*current_server = new_server;

228

mc.current_server = new_server;

229

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

247

230

} else {

248

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

249

new_server->next = *current_server;

250

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

231

new_server->next = mc.current_server;

232

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

251

233

new_server->prev->next = new_server;

252

(*current_server)->prev = new_server;

234

mc.current_server->prev = new_server;

235

}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

253

240

}

254

241

return true;

255

242

}

257

244

/*

258

245

* Initialize GPGME.

259

246

*/

260

__attribute__((nonnull, warn_unused_result))

261

static bool init_gpgme(const char * const seckey,

262

const char * const pubkey,

263

const char * const tempdir,

264

mandos_context *mc){

247

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

248

const char *tempdir){

265

249

gpgme_error_t rc;

266

250

gpgme_engine_info_t engine_info;

267

251

252

268

253

/*

269

254

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

270

255

*/

271

bool import_key(const char * const filename){

256

bool import_key(const char *filename){

272

257

int ret;

273

258

int fd;

274

259

gpgme_data_t pgp_data;

286

271

return false;

287

272

}

288

273

289

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

274

rc = gpgme_op_import(mc.ctx, pgp_data);

290

275

if(rc != GPG_ERR_NO_ERROR){

291

276

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

292

277

gpgme_strsource(rc), gpgme_strerror(rc));

336

321

}

337

322

338

323

/* Create new GPGME "context" */

339

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

324

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

340

325

if(rc != GPG_ERR_NO_ERROR){

341

326

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

342

327

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

355

340

* Decrypt OpenPGP data.

356

341

* Returns -1 on error

357

342

*/

358

__attribute__((nonnull, warn_unused_result))

359

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

360

344

size_t crypto_size,

361

char **plaintext,

362

mandos_context *mc){

345

char **plaintext){

363

346

gpgme_data_t dh_crypto, dh_plain;

364

347

gpgme_error_t rc;

365

348

ssize_t ret;

391

374

392

375

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

393

376

data buffer */

394

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

377

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

395

378

if(rc != GPG_ERR_NO_ERROR){

396

379

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

397

380

gpgme_strsource(rc), gpgme_strerror(rc));

398

381

plaintext_length = -1;

399

382

if(debug){

400

383

gpgme_decrypt_result_t result;

401

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

402

385

if(result == NULL){

403

386

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

404

387

} else {

481

464

return plaintext_length;

482

465

}

483

466

484

__attribute__((warn_unused_result))

485

static const char *safer_gnutls_strerror(int value){

486

const char *ret = gnutls_strerror(value);

467

static const char * safer_gnutls_strerror(int value){

468

const char *ret = gnutls_strerror(value); /* Spurious warning from

469

-Wunreachable-code */

487

470

if(ret == NULL)

488

471

ret = "(unknown)";

489

472

return ret;

490

473

}

491

474

492

475

/* GnuTLS log function callback */

493

__attribute__((nonnull))

494

476

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

495

477

const char* string){

496

478

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

497

479

}

498

480

499

__attribute__((nonnull, warn_unused_result))

500

481

static int init_gnutls_global(const char *pubkeyfilename,

501

const char *seckeyfilename,

502

mandos_context *mc){

482

const char *seckeyfilename){

503

483

int ret;

504

484

505

485

if(debug){

522

502

}

523

503

524

504

/* OpenPGP credentials */

525

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

526

506

if(ret != GNUTLS_E_SUCCESS){

527

507

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

528

508

safer_gnutls_strerror(ret));

538

518

}

539

519

540

520

ret = gnutls_certificate_set_openpgp_key_file

541

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

542

522

GNUTLS_OPENPGP_FMT_BASE64);

543

523

if(ret != GNUTLS_E_SUCCESS){

544

524

fprintf_plus(stderr,

550

530

}

551

531

552

532

/* GnuTLS server initialization */

553

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

554

534

if(ret != GNUTLS_E_SUCCESS){

555

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

556

536

" initialization: %s\n",

557

537

safer_gnutls_strerror(ret));

558

538

goto globalfail;

559

539

}

560

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

540

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

561

541

if(ret != GNUTLS_E_SUCCESS){

562

542

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

563

543

safer_gnutls_strerror(ret));

564

544

goto globalfail;

565

545

}

566

546

567

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

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

568

548

569

549

return 0;

570

550

571

551

globalfail:

572

552

573

gnutls_certificate_free_credentials(mc->cred);

553

gnutls_certificate_free_credentials(mc.cred);

574

554

gnutls_global_deinit();

575

gnutls_dh_params_deinit(mc->dh_params);

555

gnutls_dh_params_deinit(mc.dh_params);

576

556

return -1;

577

557

}

578

558

579

__attribute__((nonnull, warn_unused_result))

580

static int init_gnutls_session(gnutls_session_t *session,

581

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

582

560

int ret;

583

561

/* GnuTLS session creation */

584

562

do {

596

574

{

597

575

const char *err;

598

576

do {

599

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

577

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

600

578

if(quit_now){

601

579

gnutls_deinit(*session);

602

580

return -1;

613

591

614

592

do {

615

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

616

mc->cred);

594

mc.cred);

617

595

if(quit_now){

618

596

gnutls_deinit(*session);

619

597

return -1;

629

607

/* ignore client certificate if any. */

630

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

631

609

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

633

611

634

612

return 0;

635

613

}

639

617

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

640

618

641

619

/* Called when a Mandos server is found */

642

__attribute__((nonnull, warn_unused_result))

643

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

620

static int start_mandos_communication(const char *ip, uint16_t port,

644

621

AvahiIfIndex if_index,

645

int af, mandos_context *mc){

622

int af){

646

623

int ret, tcp_sd = -1;

647

624

ssize_t sret;

648

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

649

629

char *buffer = NULL;

650

630

char *decrypted_buffer = NULL;

651

631

size_t buffer_length = 0;

675

655

return -1;

676

656

}

677

657

678

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

679

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

680

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

681

bool match = false;

682

{

683

char *interface = NULL;

684

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

685

interface))){

686

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

687

match = true;

688

break;

689

}

690

}

691

}

692

if(not match){

693

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

694

connect to the server */

695

if(debug){

696

char interface[IF_NAMESIZE];

697

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

698

perror_plus("if_indextoname");

699

} else {

700

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

701

" \"%s\"\n",

702

if_indextoname((unsigned int)if_index,

703

interface));

704

}

705

}

706

return -1;

707

}

708

}

709

710

ret = init_gnutls_session(&session, mc);

658

ret = init_gnutls_session(&session);

711

659

if(ret != 0){

712

660

return -1;

713

661

}

714

662

715

663

if(debug){

716

664

fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"

717

PRIuMAX "\n", ip, (uintmax_t)port);

665

PRIu16 "\n", ip, port);

718

666

}

719

667

720

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

732

680

733

681

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

734

682

if(af == AF_INET6){

735

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

736

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

683

to.in6.sin6_family = (sa_family_t)af;

684

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

737

685

} else { /* IPv4 */

738

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

739

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

686

to.in.sin_family = (sa_family_t)af;

687

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

740

688

}

741

689

if(ret < 0 ){

742

690

int e = errno;

751

699

goto mandos_end;

752

700

}

753

701

if(af == AF_INET6){

754

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

755

if(IN6_IS_ADDR_LINKLOCAL

756

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

702

to.in6.sin6_port = htons(port); /* Spurious warnings from

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

757

709

if(if_index == AVAHI_IF_UNSPEC){

758

710

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

759

711

" incomplete without a network interface\n");

761

713

goto mandos_end;

762

714

}

763

715

/* Set the network interface number as scope */

764

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

765

717

}

766

718

} else {

767

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

768

722

}

769

723

770

724

if(quit_now){

778

732

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

779

733

perror_plus("if_indextoname");

780

734

} else {

781

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX

782

"\n", ip, interface, (uintmax_t)port);

735

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16

736

"\n", ip, interface, port);

783

737

}

784

738

} else {

785

fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",

786

ip, (uintmax_t)port);

739

fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",

740

ip, port);

787

741

}

788

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

789

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

744

const char *pcret;

790

745

if(af == AF_INET6){

791

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

792

sizeof(struct sockaddr_in6),

793

addrstr, sizeof(addrstr), NULL, 0,

794

NI_NUMERICHOST);

746

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

747

sizeof(addrstr));

795

748

} else {

796

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

797

sizeof(struct sockaddr_in),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

749

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

750

sizeof(addrstr));

800

751

}

801

if(ret == EAI_SYSTEM){

802

perror_plus("getnameinfo");

803

} else if(ret != 0) {

804

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

805

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

806

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

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

807

758

}

808

759

}

809

760

813

764

}

814

765

815

766

if(af == AF_INET6){

816

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

817

sizeof(struct sockaddr_in6));

767

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

818

768

} else {

819

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

820

sizeof(struct sockaddr_in));

769

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

821

770

}

822

771

if(ret < 0){

823

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

772

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

824

773

int e = errno;

825

774

perror_plus("connect");

826

775

errno = e;

872

821

goto mandos_end;

873

822

}

874

823

875

/* This casting via intptr_t is to eliminate warning about casting

876

an int to a pointer type. This is exactly how the GnuTLS Guile

877

function "set-session-transport-fd!" does it. */

878

gnutls_transport_set_ptr(session,

879

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

824

/* Spurious warning from -Wint-to-pointer-cast */

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

880

826

881

827

if(quit_now){

882

828

errno = EINTR;

987

933

if(buffer_length > 0){

988

934

ssize_t decrypted_buffer_size;

989

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

990

&decrypted_buffer, mc);

936

&decrypted_buffer);

991

937

if(decrypted_buffer_size >= 0){

992

938

993

939

written = 0;

1041

987

return retval;

1042

988

}

1043

989

1044

__attribute__((nonnull))

1045

990

static void resolve_callback(AvahiSServiceResolver *r,

1046

991

AvahiIfIndex interface,

1047

992

AvahiProtocol proto,

1055

1000

AVAHI_GCC_UNUSED AvahiStringList *txt,

1056

1001

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1057

1002

flags,

1058

void *mc){

1059

if(r == NULL){

1060

return;

1061

}

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1062

1005

1063

1006

/* Called whenever a service has been resolved successfully or

1064

1007

timed out */

1073

1016

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

1074

1017

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

1075

1018

domain,

1076

avahi_strerror(avahi_server_errno

1077

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

1019

avahi_strerror(avahi_server_errno(mc.server)));

1078

1020

break;

1079

1021

1080

1022

case AVAHI_RESOLVER_FOUND:

1086

1028

PRIdMAX ") on port %" PRIu16 "\n", name,

1087

1029

host_name, ip, (intmax_t)interface, port);

1088

1030

}

1089

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

1090

interface,

1091

avahi_proto_to_af(proto),

1092

mc);

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1093

1033

if(ret == 0){

1094

avahi_simple_poll_quit(simple_poll);

1034

avahi_simple_poll_quit(mc.simple_poll);

1095

1035

} else {

1096

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

1097

avahi_proto_to_af(proto),

1098

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

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1099

1038

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

1100

1039

" list\n", name);

1101

1040

}

1114

1053

const char *domain,

1115

1054

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1116

1055

flags,

1117

void *mc){

1118

if(b == NULL){

1119

return;

1120

}

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1121

1058

1122

1059

/* Called whenever a new services becomes available on the LAN or

1123

1060

is removed from the LAN */

1131

1068

case AVAHI_BROWSER_FAILURE:

1132

1069

1133

1070

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

1134

avahi_strerror(avahi_server_errno

1135

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

1136

avahi_simple_poll_quit(simple_poll);

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1137

1073

return;

1138

1074

1139

1075

case AVAHI_BROWSER_NEW:

1142

1078

the callback function is called the Avahi server will free the

1143

1079

resolver for us. */

1144

1080

1145

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

1146

interface, protocol, name, type,

1147

domain, protocol, 0,

1148

resolve_callback, mc) == NULL)

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1149

1084

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

1150

1085

" %s\n", name,

1151

avahi_strerror(avahi_server_errno

1152

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

1086

avahi_strerror(avahi_server_errno(mc.server)));

1153

1087

break;

1154

1088

1155

1089

case AVAHI_BROWSER_REMOVE:

1174

1108

signal_received = sig;

1175

1109

int old_errno = errno;

1176

1110

/* set main loop to exit */

1177

if(simple_poll != NULL){

1178

avahi_simple_poll_quit(simple_poll);

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1179

1113

}

1180

1114

errno = old_errno;

1181

1115

}

1182

1116

1183

__attribute__((nonnull, warn_unused_result))

1184

1117

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

1185

1118

int ret;

1186

error_t ret_errno;

1187

1119

1188

1120

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

1189

1121

if(s < 0){

1190

ret_errno = errno;

1191

1122

perror_plus("socket");

1192

errno = ret_errno;

1193

1123

return false;

1194

1124

}

1195

1125

strcpy(ifr->ifr_name, ifname);

1196

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1197

1127

if(ret == -1){

1198

1128

if(debug){

1199

ret_errno = errno;

1200

1129

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1202

1130

}

1203

1131

return false;

1204

1132

}

1205

1133

return true;

1206

1134

}

1207

1135

1208

__attribute__((nonnull, warn_unused_result))

1209

1136

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

1210

1137

1211

1138

/* Reject the loopback device */

1253

1180

* corresponds to an acceptable network device.

1254

1181

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

1255

1182

*/

1256

__attribute__((nonnull, warn_unused_result))

1257

1183

int good_interface(const struct dirent *if_entry){

1258

1184

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

1259

1185

return 0;

1275

1201

}

1276

1202

1277

1203

/*

1278

* This function determines if a network interface is up.

1279

*/

1280

__attribute__((nonnull, warn_unused_result))

1281

bool interface_is_up(const char *interface){

1282

struct ifreq ifr;

1283

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

1284

if(debug){

1285

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

1286

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

1287

}

1288

return false;

1289

}

1290

1291

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

1292

}

1293

1294

/*

1295

* This function determines if a network interface is running

1296

*/

1297

__attribute__((nonnull, warn_unused_result))

1298

bool interface_is_running(const char *interface){

1299

struct ifreq ifr;

1300

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

1301

if(debug){

1302

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

1303

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

1304

}

1305

return false;

1306

}

1307

1308

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

1309

}

1310

1311

__attribute__((nonnull, pure, warn_unused_result))

1204

* This function determines if a directory entry in /sys/class/net

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

if(not get_flags(if_entry->d_name, &ifr)){

1215

if(debug){

1216

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

1217

"\"%s\"\n", if_entry->d_name);

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

if(not (ifr.ifr_flags & IFF_UP)){

1224

if(debug){

1225

fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

if(not (ifr.ifr_flags & IFF_RUNNING)){

1233

if(debug){

1234

fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

if(not good_flags(if_entry->d_name, &ifr)){

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1312

1246

int notdotentries(const struct dirent *direntry){

1313

1247

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

1314

1248

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

1321

1255

}

1322

1256

1323

1257

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

1324

__attribute__((nonnull, warn_unused_result))

1325

1258

int runnable_hook(const struct dirent *direntry){

1326

1259

int ret;

1327

1260

size_t sret;

1382

1315

return 1;

1383

1316

}

1384

1317

1385

__attribute__((nonnull, warn_unused_result))

1386

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1387

mandos_context *mc){

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1388

1319

int ret;

1389

1320

struct timespec now;

1390

1321

struct timespec waited_time;

1391

1322

intmax_t block_time;

1392

1323

1393

1324

while(true){

1394

if(mc->current_server == NULL){

1395

if(debug){

1325

if(mc.current_server == NULL){

1326

if (debug){

1396

1327

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

1397

1328

" No timeout!\n");

1398

1329

}

1399

1330

ret = avahi_simple_poll_iterate(s, -1);

1400

1331

} else {

1401

if(debug){

1332

if (debug){

1402

1333

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

1403

1334

" it, or wait\n");

1404

1335

}

1411

1342

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

1412

1343

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

1413

1344

waited_time.tv_sec = (now.tv_sec

1414

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

1345

- mc.current_server->last_seen.tv_sec);

1415

1346

waited_time.tv_nsec = (now.tv_nsec

1416

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

1347

- mc.current_server->last_seen.tv_nsec);

1417

1348

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

1418

1349

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

1419

1350

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

1421

1352

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

1422

1353

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

1423

1354

1424

if(debug){

1355

if (debug){

1425

1356

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

1426

1357

block_time);

1427

1358

}

1428

1359

1429

1360

if(block_time <= 0){

1430

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

1431

mc->current_server->port,

1432

mc->current_server->if_index,

1433

mc->current_server->af, mc);

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

1434

1365

if(ret == 0){

1435

avahi_simple_poll_quit(s);

1366

avahi_simple_poll_quit(mc.simple_poll);

1436

1367

return 0;

1437

1368

}

1438

1369

ret = clock_gettime(CLOCK_MONOTONIC,

1439

&mc->current_server->last_seen);

1370

&mc.current_server->last_seen);

1440

1371

if(ret == -1){

1441

1372

perror_plus("clock_gettime");

1442

1373

return -1;

1443

1374

}

1444

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

1375

mc.current_server = mc.current_server->next;

1445

1376

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

1446

1377

servers, but don't block */

1447

1378

}

1449

1380

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

1450

1381

}

1451

1382

if(ret != 0){

1452

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

1383

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

1453

1384

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

1454

1385

}

1455

1386

}

1456

1387

}

1457

1388

}

1458

1389

1459

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

1460

__attribute__((warn_unused_result))

1461

error_t raise_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

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

1473

__attribute__((warn_unused_result))

1474

error_t raise_privileges_permanently(void){

1475

error_t old_errno = errno;

1476

error_t ret_errno = raise_privileges();

1477

if(ret_errno != 0){

1478

errno = old_errno;

1479

return ret_errno;

1480

}

1481

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

1482

ret_errno = errno;

1483

perror_plus("seteuid");

1484

}

1485

errno = old_errno;

1486

return ret_errno;

1487

}

1488

1489

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

1490

__attribute__((warn_unused_result))

1491

error_t lower_privileges(void){

1492

error_t old_errno = errno;

1493

error_t ret_errno = 0;

1494

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

1495

ret_errno = errno;

1496

perror_plus("seteuid");

1497

}

1498

errno = old_errno;

1499

return ret_errno;

1500

}

1501

1502

/* Lower privileges permanently */

1503

__attribute__((warn_unused_result))

1504

error_t lower_privileges_permanently(void){

1505

error_t old_errno = errno;

1506

error_t ret_errno = 0;

1507

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

1508

ret_errno = errno;

1509

perror_plus("setuid");

1510

}

1511

errno = old_errno;

1512

return ret_errno;

1513

}

1514

1515

__attribute__((nonnull))

1516

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

1390

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

1517

1391

const float delay){

1518

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1519

1395

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

1520

1396

alphasort);

1521

1397

if(numhooks == -1){

1522

if(errno == ENOENT){

1523

if(debug){

1524

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

1525

" found\n", hookdir);

1526

}

1527

} else {

1528

perror_plus("scandir");

1529

}

1398

perror_plus("scandir");

1530

1399

} else {

1531

struct dirent *direntry;

1532

int ret;

1533

1400

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

1534

1401

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

1535

1402

direntry = direntries[i];

1547

1414

if(hook_pid == 0){

1548

1415

/* Child */

1549

1416

/* Raise privileges */

1550

if(raise_privileges_permanently() != 0){

1551

perror_plus("Failed to raise privileges");

1552

_exit(EX_NOPERM);

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1553

1427

}

1554

1428

/* Set group */

1555

1429

errno = 0;

1556

1430

ret = setgid(0);

1557

1431

if(ret == -1){

1558

1432

perror_plus("setgid");

1559

_exit(EX_NOPERM);

1560

1433

}

1561

1434

/* Reset supplementary groups */

1562

1435

errno = 0;

1563

1436

ret = setgroups(0, NULL);

1564

1437

if(ret == -1){

1565

1438

perror_plus("setgroups");

1566

_exit(EX_NOPERM);

1567

}

1568

ret = dup2(devnull, STDIN_FILENO);

1569

if(ret == -1){

1570

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

1571

_exit(EX_OSERR);

1572

}

1573

ret = close(devnull);

1574

if(ret == -1){

1575

perror_plus("close");

1576

_exit(EX_OSERR);

1577

}

1578

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1579

if(ret == -1){

1580

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

1581

_exit(EX_OSERR);

1582

}

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1583

1443

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

1584

1444

if(ret == -1){

1585

1445

perror_plus("setenv");

1601

1461

_exit(EX_OSERR);

1602

1462

}

1603

1463

char *delaystring;

1604

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

1464

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

1605

1465

if(ret == -1){

1606

1466

perror_plus("asprintf");

1607

1467

_exit(EX_OSERR);

1660

1520

}

1661

1521

close(devnull);

1662

1522

}

1663

}

1664

1665

__attribute__((nonnull, warn_unused_result))

1666

error_t bring_up_interface(const char *const interface,

1667

const float delay){

1668

error_t old_errno = errno;

1669

int ret;

1670

struct ifreq network;

1671

unsigned int if_index = if_nametoindex(interface);

1672

if(if_index == 0){

1673

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

1674

errno = old_errno;

1675

return ENXIO;

1676

}

1677

1678

if(quit_now){

1679

errno = old_errno;

1680

return EINTR;

1681

}

1682

1683

if(not interface_is_up(interface)){

1684

error_t ret_errno = 0, ioctl_errno = 0;

1685

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

1686

ret_errno = errno;

1687

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

1688

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

1689

errno = old_errno;

1690

return ret_errno;

1691

}

1692

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

1693

1694

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

1695

if(sd == -1){

1696

ret_errno = errno;

1697

perror_plus("socket");

1698

errno = old_errno;

1699

return ret_errno;

1700

}

1701

1702

if(quit_now){

1703

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

1704

if(ret == -1){

1705

perror_plus("close");

1706

}

1707

errno = old_errno;

1708

return EINTR;

1709

}

1710

1711

if(debug){

1712

fprintf_plus(stderr, "Bringing up interface \"%s\"\n",

1713

interface);

1714

}

1715

1716

/* Raise privileges */

1717

ret_errno = raise_privileges();

1718

if(ret_errno != 0){

1719

perror_plus("Failed to raise privileges");

1720

}

1721

1722

#ifdef __linux__

1723

int ret_linux;

1724

bool restore_loglevel = false;

1725

if(ret_errno == 0){

1726

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1727

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

1728

ret_linux = klogctl(8, NULL, 5);

1729

if(ret_linux == -1){

1730

perror_plus("klogctl");

1731

} else {

1732

restore_loglevel = true;

1733

}

1734

}

1735

#endif /* __linux__ */

1736

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

1737

ioctl_errno = errno;

1738

#ifdef __linux__

1739

if(restore_loglevel){

1740

ret_linux = klogctl(7, NULL, 0);

1741

if(ret_linux == -1){

1742

perror_plus("klogctl");

1743

}

1744

}

1745

#endif /* __linux__ */

1746

1747

/* If raise_privileges() succeeded above */

1748

if(ret_errno == 0){

1749

/* Lower privileges */

1750

ret_errno = lower_privileges();

1751

if(ret_errno != 0){

1752

errno = ret_errno;

1753

perror_plus("Failed to lower privileges");

1754

}

1755

}

1756

1757

/* Close the socket */

1758

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

1759

if(ret == -1){

1760

perror_plus("close");

1761

}

1762

1763

if(ret_setflags == -1){

1764

errno = ioctl_errno;

1765

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1766

errno = old_errno;

1767

return ioctl_errno;

1768

}

1769

} else if(debug){

1770

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

1771

interface);

1772

}

1773

1774

/* Sleep checking until interface is running.

1775

Check every 0.25s, up to total time of delay */

1776

for(int i=0; i < delay * 4; i++){

1777

if(interface_is_running(interface)){

1778

break;

1779

}

1780

struct timespec sleeptime = { .tv_nsec = 250000000 };

1781

ret = nanosleep(&sleeptime, NULL);

1782

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

1783

perror_plus("nanosleep");

1784

}

1785

}

1786

1787

errno = old_errno;

1788

return 0;

1789

}

1790

1791

__attribute__((nonnull, warn_unused_result))

1792

error_t take_down_interface(const char *const interface){

1793

error_t old_errno = errno;

1794

struct ifreq network;

1795

unsigned int if_index = if_nametoindex(interface);

1796

if(if_index == 0){

1797

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

1798

errno = old_errno;

1799

return ENXIO;

1800

}

1801

if(interface_is_up(interface)){

1802

error_t ret_errno = 0, ioctl_errno = 0;

1803

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

1804

ret_errno = errno;

1805

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

1806

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

1807

errno = old_errno;

1808

return ret_errno;

1809

}

1810

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

1811

1812

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

1813

if(sd == -1){

1814

ret_errno = errno;

1815

perror_plus("socket");

1816

errno = old_errno;

1817

return ret_errno;

1818

}

1819

1820

if(debug){

1821

fprintf_plus(stderr, "Taking down interface \"%s\"\n",

1822

interface);

1823

}

1824

1825

/* Raise privileges */

1826

ret_errno = raise_privileges();

1827

if(ret_errno != 0){

1828

perror_plus("Failed to raise privileges");

1829

}

1830

1831

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

1832

ioctl_errno = errno;

1833

1834

/* If raise_privileges() succeeded above */

1835

if(ret_errno == 0){

1836

/* Lower privileges */

1837

ret_errno = lower_privileges();

1838

if(ret_errno != 0){

1839

errno = ret_errno;

1840

perror_plus("Failed to lower privileges");

1841

}

1842

}

1843

1844

/* Close the socket */

1845

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

1846

if(ret == -1){

1847

perror_plus("close");

1848

}

1849

1850

if(ret_setflags == -1){

1851

errno = ioctl_errno;

1852

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1853

errno = old_errno;

1854

return ioctl_errno;

1855

}

1856

} else if(debug){

1857

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

1858

interface);

1859

}

1860

1861

errno = old_errno;

1862

return 0;

1523

return true;

1863

1524

}

1864

1525

1865

1526

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

1866

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

1867

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

1868

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

1869

.interfaces = NULL, .interfaces_size = 0 };

1870

1527

AvahiSServiceBrowser *sb = NULL;

1871

error_t ret_errno;

1528

int error;

1872

1529

int ret;

1873

1530

intmax_t tmpmax;

1874

1531

char *tmp;

1875

1532

int exitcode = EXIT_SUCCESS;

1876

char *interfaces_to_take_down = NULL;

1877

size_t interfaces_to_take_down_size = 0;

1878

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

1879

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

1880

char *tempdir = NULL;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1539

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

1540

bool tempdir_created = false;

1881

1541

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1882

1542

const char *seckey = PATHDIR "/" SECKEY;

1883

1543

const char *pubkey = PATHDIR "/" PUBKEY;

1884

char *interfaces_hooks = NULL;

1885

1544

1886

1545

bool gnutls_initialized = false;

1887

1546

bool gpgme_initialized = false;

1978

1637

connect_to = arg;

1979

1638

break;

1980

1639

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

1981

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

1982

arg, (int)',');

1983

if(ret_errno != 0){

1984

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

1985

}

1640

interface = arg;

1986

1641

break;

1987

1642

case 's': /* --seckey */

1988

1643

seckey = arg;

2065

1720

/* Work around Debian bug #633582:

2066

1721

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

2067

1722

2068

/* Re-raise privileges */

2069

ret_errno = raise_privileges();

2070

if(ret_errno != 0){

2071

errno = ret_errno;

2072

perror_plus("Failed to raise privileges");

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

2073

1728

} else {

2074

1729

struct stat st;

2075

1730

2116

1771

}

2117

1772

2118

1773

/* Lower privileges */

2119

ret_errno = lower_privileges();

2120

if(ret_errno != 0){

2121

errno = ret_errno;

2122

perror_plus("Failed to lower privileges");

2123

}

2124

}

2125

}

2126

2127

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

2128

{

2129

char *interface = NULL;

2130

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

2131

interface))){

2132

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

2133

and if_nametoindex(interface) == 0){

2134

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

2135

fprintf_plus(stderr, "Not using nonexisting interface"

2136

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

2137

}

2138

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

2139

interface = NULL;

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

2140

1778

}

2141

1779

}

2142

1780

}

2143

1781

2144

1782

/* Run network hooks */

2145

{

2146

if(mc.interfaces != NULL){

2147

interfaces_hooks = malloc(mc.interfaces_size);

2148

if(interfaces_hooks == NULL){

2149

perror_plus("malloc");

2150

goto end;

2151

}

2152

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

2153

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

2154

}

2155

run_network_hooks("start", interfaces_hooks != NULL ?

2156

interfaces_hooks : "", delay);

1783

if(not run_network_hooks("start", interface, delay)){

1784

goto end;

2157

1785

}

2158

1786

2159

1787

if(not debug){

2160

1788

avahi_set_log_function(empty_log);

2161

1789

}

2162

1790

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

/* No up interfaces, look for any good interfaces */

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

interface = strdup(direntries[0]->d_name);

1805

if(debug){

1806

fprintf_plus(stderr, "Using interface \"%s\"\n", interface);

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

2163

1823

/* Initialize Avahi early so avahi_simple_poll_quit() can be called

2164

1824

from the signal handler */

2165

1825

/* Initialize the pseudo-RNG for Avahi */

2166

1826

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

2167

simple_poll = avahi_simple_poll_new();

2168

if(simple_poll == NULL){

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2169

1829

fprintf_plus(stderr,

2170

1830

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

2171

1831

exitcode = EX_UNAVAILABLE;

2235

1895

}

2236

1896

}

2237

1897

2238

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

2239

if(mc.interfaces == NULL){

2240

struct dirent **direntries;

2241

/* Look for any good interfaces */

2242

ret = scandir(sys_class_net, &direntries, good_interface,

2243

alphasort);

2244

if(ret >= 1){

2245

/* Add all found interfaces to interfaces list */

2246

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

2247

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

2248

direntries[i]->d_name);

2249

if(ret_errno != 0){

2250

errno = ret_errno;

2251

perror_plus("argz_add");

2252

continue;

2253

}

2254

if(debug){

2255

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

2256

direntries[i]->d_name);

2257

}

2258

}

2259

free(direntries);

2260

} else {

2261

free(direntries);

2262

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

2263

exitcode = EXIT_FAILURE;

2264

goto end;

2265

}

2266

}

2267

2268

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

2269

{

2270

char *interface = NULL;

2271

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

2272

interface))){

2273

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

2274

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

2275

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

2276

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

2277

interface);

2278

interface = NULL;

2279

while((interface = argz_next(mc.interfaces,

2280

mc.interfaces_size, interface))){

2281

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

2282

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

2283

interface);

2284

interface = NULL;

1898

/* If the interface is down, bring it up */

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

if((network.ifr_flags & IFF_UP) == 0){

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

2285

1983

}

2286

1984

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

Check every 0.25s, up to total time of delay */

1997

for(int i=0; i < delay * 4; i++){

1998

ret = ioctl(sd, SIOCGIFFLAGS, &network);

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2287

2002

break;

2288

2003

}

2289

bool interface_was_up = interface_is_up(interface);

2290

errno = bring_up_interface(interface, delay);

2291

if(not interface_was_up){

2292

if(errno != 0){

2293

perror_plus("Failed to bring up interface");

2294

} else {

2295

errno = argz_add(&interfaces_to_take_down,

2296

&interfaces_to_take_down_size,

2297

interface);

2298

if(errno != 0){

2299

perror_plus("argz_add");

2300

}

2301

}

2302

}

2303

}

2304

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

2305

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

2306

}

2307

}

2308

2309

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

2310

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

2311

if(debug){

2312

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

2313

mc.interfaces);

2314

}

2315

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

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

/* We won't need the socket anymore */

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2316

2033

}

2317

2034

2318

2035

if(quit_now){

2319

2036

goto end;

2320

2037

}

2321

2038

2322

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

2039

ret = init_gnutls_global(pubkey, seckey);

2323

2040

if(ret == -1){

2324

2041

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

2325

2042

exitcode = EX_UNAVAILABLE;

2332

2049

goto end;

2333

2050

}

2334

2051

2335

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

2336

tempdir = mkdtemp(run_tempdir);

2337

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

2338

if(debug){

2339

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

2340

run_tempdir, old_tempdir);

2341

}

2342

tempdir = mkdtemp(old_tempdir);

2343

}

2344

if(tempdir == NULL){

2052

if(mkdtemp(tempdir) == NULL){

2345

2053

perror_plus("mkdtemp");

2346

2054

goto end;

2347

2055

}

2056

tempdir_created = true;

2348

2057

2349

2058

if(quit_now){

2350

2059

goto end;

2351

2060

}

2352

2061

2353

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

2062

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

2354

2063

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

2355

2064

exitcode = EX_UNAVAILABLE;

2356

2065

goto end;

2366

2075

/* Connect directly, do not use Zeroconf */

2367

2076

/* (Mainly meant for debugging) */

2368

2077

char *address = strrchr(connect_to, ':');

2369

2370

2078

if(address == NULL){

2371

2079

fprintf_plus(stderr, "No colon in address\n");

2372

2080

exitcode = EX_USAGE;

2377

2085

goto end;

2378

2086

}

2379

2087

2380

in_port_t port;

2088

uint16_t port;

2381

2089

errno = 0;

2382

2090

tmpmax = strtoimax(address+1, &tmp, 10);

2383

2091

if(errno != 0 or tmp == address+1 or *tmp != '\0'

2384

or tmpmax != (in_port_t)tmpmax){

2092

or tmpmax != (uint16_t)tmpmax){

2385

2093

fprintf_plus(stderr, "Bad port number\n");

2386

2094

exitcode = EX_USAGE;

2387

2095

goto end;

2388

2096

}

2389

2097

2390

2098

if(quit_now){

2391

2099

goto end;

2392

2100

}

2393

2101

2394

port = (in_port_t)tmpmax;

2102

port = (uint16_t)tmpmax;

2395

2103

*address = '\0';

2396

2104

/* Colon in address indicates IPv6 */

2397

2105

int af;

2413

2121

}

2414

2122

2415

2123

while(not quit_now){

2416

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

2417

&mc);

2124

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

2418

2125

if(quit_now or ret == 0){

2419

2126

break;

2420

2127

}

2422

2129

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

2423

2130

(int)retry_interval);

2424

2131

}

2425

sleep((unsigned int)retry_interval);

2132

sleep((int)retry_interval);

2426

2133

}

2427

2134

2428

if(not quit_now){

2135

if (not quit_now){

2429

2136

exitcode = EXIT_SUCCESS;

2430

2137

}

2431

2138

2446

2153

config.publish_domain = 0;

2447

2154

2448

2155

/* Allocate a new server */

2449

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2450

&config, NULL, NULL, &ret_errno);

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

2451

2159

2452

2160

/* Free the Avahi configuration data */

2453

2161

avahi_server_config_free(&config);

2456

2164

/* Check if creating the Avahi server object succeeded */

2457

2165

if(mc.server == NULL){

2458

2166

fprintf_plus(stderr, "Failed to create Avahi server: %s\n",

2459

avahi_strerror(ret_errno));

2167

avahi_strerror(error));

2460

2168

exitcode = EX_UNAVAILABLE;

2461

2169

goto end;

2462

2170

}

2468

2176

/* Create the Avahi service browser */

2469

2177

sb = avahi_s_service_browser_new(mc.server, if_index,

2470

2178

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2471

NULL, 0, browse_callback,

2472

(void *)&mc);

2179

NULL, 0, browse_callback, NULL);

2473

2180

if(sb == NULL){

2474

2181

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

2475

2182

avahi_strerror(avahi_server_errno(mc.server)));

2487

2194

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

2488

2195

}

2489

2196

2490

ret = avahi_loop_with_timeout(simple_poll,

2491

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

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

2492

2199

if(debug){

2493

2200

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

2494

2201

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

2501

2208

}

2502

2209

2503

2210

/* Cleanup things */

2504

free(mc.interfaces);

2505

2506

2211

if(sb != NULL)

2507

2212

avahi_s_service_browser_free(sb);

2508

2213

2509

2214

if(mc.server != NULL)

2510

2215

avahi_server_free(mc.server);

2511

2216

2512

if(simple_poll != NULL)

2513

avahi_simple_poll_free(simple_poll);

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

2514

2219

2515

2220

if(gnutls_initialized){

2516

2221

gnutls_certificate_free_credentials(mc.cred);

2533

2238

}

2534

2239

}

2535

2240

2536

/* Re-raise privileges */

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

2537

2245

{

2538

ret_errno = raise_privileges();

2539

if(ret_errno != 0){

2540

perror_plus("Failed to raise privileges");

2541

} else {

2542

2543

/* Run network hooks */

2544

run_network_hooks("stop", interfaces_hooks != NULL ?

2545

interfaces_hooks : "", delay);

2546

2547

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

2548

{

2549

char *interface = NULL;

2550

while((interface=argz_next(interfaces_to_take_down,

2551

interfaces_to_take_down_size,

2552

interface))){

2553

ret_errno = take_down_interface(interface);

2554

if(ret_errno != 0){

2555

errno = ret_errno;

2556

perror_plus("Failed to take down interface");

2557

}

2558

}

2559

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

2560

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

2561

" down\n");

2562

}

2563

}

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

2564

2250

}

2565

2251

2566

ret_errno = lower_privileges_permanently();

2567

if(ret_errno != 0){

2568

perror_plus("Failed to lower privileges permanently");

2252

/* Take down the network interface */

2253

if(take_down_interface and geteuid() == 0){

2254

ret = ioctl(sd, SIOCGIFFLAGS, &network);

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

2569

2268

}

2570

2269

}

2571

2572

free(interfaces_to_take_down);

2573

free(interfaces_hooks);

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2574

2276

2575

2277

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

2576

if(tempdir != NULL){

2278

if(tempdir_created){

2577

2279

struct dirent **direntries = NULL;

2578

2280

struct dirent *direntry = NULL;

2579

2281

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

2580

2282

alphasort);

2581

if(numentries > 0){

2283

if (numentries > 0){

2582

2284

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

2583

2285

direntry = direntries[i];

2584

2286

char *fullname = NULL;

2599

2301

2600

2302

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

2601

2303

free(direntries);

2602

if(numentries == -1){

2304

if (numentries == -1){

2603

2305

perror_plus("scandir");

2604

2306

}

2605

2307

ret = rmdir(tempdir);