/mandos/release : revision 237.7.229

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 */

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(),

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() */

58

inet_pton(), connect(),

59

getnameinfo() */

59

60

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

60

61

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

61

62

*/

62

63

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

63

64

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, inet_ntop() */

77

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

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() */

91

97

92

98

#ifdef __linux__

93

99

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

135

141

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

136

142

char *connect_to = NULL;

137

143

const char *hookdir = HOOKDIR;

144

uid_t uid = 65534;

145

gid_t gid = 65534;

138

146

139

147

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

140

148

typedef struct server{

141

149

const char *ip;

142

uint16_t port;

150

in_port_t port;

143

151

AvahiIfIndex if_index;

144

152

int af;

145

153

struct timespec last_seen;

149

157

150

158

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

151

159

typedef struct {

152

AvahiSimplePoll *simple_poll;

153

160

AvahiServer *server;

154

161

gnutls_certificate_credentials_t cred;

155

162

unsigned int dh_bits;

157

164

const char *priority;

158

165

gpgme_ctx_t ctx;

159

166

server *current_server;

167

char *interfaces;

168

size_t interfaces_size;

160

169

} mandos_context;

161

170

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 };

171

/* global so signal handler can reach it*/

172

AvahiSimplePoll *simple_poll;

167

173

168

174

sig_atomic_t quit_now = 0;

169

175

int signal_received = 0;

177

183

perror(print_text);

178

184

}

179

185

180

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

186

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

181

187

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

182

188

va_list ap;

183

189

va_start (ap, format);

184

190

185

191

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

186

192

program_invocation_short_name));

187

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

193

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

188

194

}

189

195

190

196

/*

192

198

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

193

199

* "buffer_length" is how much is already used.

194

200

*/

201

__attribute__((nonnull, warn_unused_result))

195

202

size_t incbuffer(char **buffer, size_t buffer_length,

196

203

size_t buffer_capacity){

197

204

if(buffer_length + BUFFER_SIZE > buffer_capacity){

198

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

199

if(buffer == NULL){

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;

200

211

return 0;

201

212

}

213

*buffer = new_buf;

202

214

buffer_capacity += BUFFER_SIZE;

203

215

}

204

216

return buffer_capacity;

205

217

}

206

218

207

219

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

208

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

209

int af){

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){

210

223

int ret;

211

224

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

212

225

if(new_server == NULL){

221

234

perror_plus("strdup");

222

235

return false;

223

236

}

237

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

240

return false;

241

}

224

242

/* Special case of first server */

225

if (mc.current_server == NULL){

243

if(*current_server == NULL){

226

244

new_server->next = new_server;

227

245

new_server->prev = new_server;

228

mc.current_server = new_server;

229

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

246

*current_server = new_server;

230

247

} else {

231

new_server->next = mc.current_server;

232

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

248

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

249

new_server->next = *current_server;

250

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

233

251

new_server->prev->next = 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;

252

(*current_server)->prev = new_server;

240

253

}

241

254

return true;

242

255

}

244

257

/*

245

258

* Initialize GPGME.

246

259

*/

247

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

248

const char *tempdir){

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){

249

265

gpgme_error_t rc;

250

266

gpgme_engine_info_t engine_info;

251

267

252

253

268

/*

254

269

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

255

270

*/

256

bool import_key(const char *filename){

271

bool import_key(const char * const filename){

257

272

int ret;

258

273

int fd;

259

274

gpgme_data_t pgp_data;

271

286

return false;

272

287

}

273

288

274

rc = gpgme_op_import(mc.ctx, pgp_data);

289

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

275

290

if(rc != GPG_ERR_NO_ERROR){

276

291

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

277

292

gpgme_strsource(rc), gpgme_strerror(rc));

321

336

}

322

337

323

338

/* Create new GPGME "context" */

324

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

339

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

325

340

if(rc != GPG_ERR_NO_ERROR){

326

341

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

327

342

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

340

355

* Decrypt OpenPGP data.

341

356

* Returns -1 on error

342

357

*/

358

__attribute__((nonnull, warn_unused_result))

343

359

static ssize_t pgp_packet_decrypt(const char *cryptotext,

344

360

size_t crypto_size,

345

char **plaintext){

361

char **plaintext,

362

mandos_context *mc){

346

363

gpgme_data_t dh_crypto, dh_plain;

347

364

gpgme_error_t rc;

348

365

ssize_t ret;

374

391

375

392

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

376

393

data buffer */

377

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

394

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

378

395

if(rc != GPG_ERR_NO_ERROR){

379

396

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

380

397

gpgme_strsource(rc), gpgme_strerror(rc));

381

398

plaintext_length = -1;

382

399

if(debug){

383

400

gpgme_decrypt_result_t result;

384

result = gpgme_op_decrypt_result(mc.ctx);

401

result = gpgme_op_decrypt_result(mc->ctx);

385

402

if(result == NULL){

386

403

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

387

404

} else {

464

481

return plaintext_length;

465

482

}

466

483

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

484

__attribute__((warn_unused_result))

485

static const char *safer_gnutls_strerror(int value){

486

const char *ret = gnutls_strerror(value);

470

487

if(ret == NULL)

471

488

ret = "(unknown)";

472

489

return ret;

473

490

}

474

491

475

492

/* GnuTLS log function callback */

493

__attribute__((nonnull))

476

494

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

477

495

const char* string){

478

496

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

479

497

}

480

498

499

__attribute__((nonnull, warn_unused_result))

481

500

static int init_gnutls_global(const char *pubkeyfilename,

482

const char *seckeyfilename){

501

const char *seckeyfilename,

502

mandos_context *mc){

483

503

int ret;

484

504

485

505

if(debug){

502

522

}

503

523

504

524

/* OpenPGP credentials */

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

525

ret = gnutls_certificate_allocate_credentials(&mc->cred);

506

526

if(ret != GNUTLS_E_SUCCESS){

507

527

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

508

528

safer_gnutls_strerror(ret));

518

538

}

519

539

520

540

ret = gnutls_certificate_set_openpgp_key_file

521

(mc.cred, pubkeyfilename, seckeyfilename,

541

(mc->cred, pubkeyfilename, seckeyfilename,

522

542

GNUTLS_OPENPGP_FMT_BASE64);

523

543

if(ret != GNUTLS_E_SUCCESS){

524

544

fprintf_plus(stderr,

530

550

}

531

551

532

552

/* GnuTLS server initialization */

533

ret = gnutls_dh_params_init(&mc.dh_params);

553

ret = gnutls_dh_params_init(&mc->dh_params);

534

554

if(ret != GNUTLS_E_SUCCESS){

535

555

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

536

556

" initialization: %s\n",

537

557

safer_gnutls_strerror(ret));

538

558

goto globalfail;

539

559

}

540

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

560

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

541

561

if(ret != GNUTLS_E_SUCCESS){

542

562

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

543

563

safer_gnutls_strerror(ret));

544

564

goto globalfail;

545

565

}

546

566

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

567

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

548

568

549

569

return 0;

550

570

551

571

globalfail:

552

572

553

gnutls_certificate_free_credentials(mc.cred);

573

gnutls_certificate_free_credentials(mc->cred);

554

574

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

575

gnutls_dh_params_deinit(mc->dh_params);

556

576

return -1;

557

577

}

558

578

559

static int init_gnutls_session(gnutls_session_t *session){

579

__attribute__((nonnull, warn_unused_result))

580

static int init_gnutls_session(gnutls_session_t *session,

581

mandos_context *mc){

560

582

int ret;

561

583

/* GnuTLS session creation */

562

584

do {

574

596

{

575

597

const char *err;

576

598

do {

577

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

599

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

578

600

if(quit_now){

579

601

gnutls_deinit(*session);

580

602

return -1;

591

613

592

614

do {

593

615

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

594

mc.cred);

616

mc->cred);

595

617

if(quit_now){

596

618

gnutls_deinit(*session);

597

619

return -1;

607

629

/* ignore client certificate if any. */

608

630

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

609

631

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

611

633

612

634

return 0;

613

635

}

617

639

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

618

640

619

641

/* Called when a Mandos server is found */

620

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

642

__attribute__((nonnull, warn_unused_result))

643

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

621

644

AvahiIfIndex if_index,

622

int af){

645

int af, mandos_context *mc){

623

646

int ret, tcp_sd = -1;

624

647

ssize_t sret;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

648

struct sockaddr_storage to;

629

649

char *buffer = NULL;

630

650

char *decrypted_buffer = NULL;

631

651

size_t buffer_length = 0;

655

675

return -1;

656

676

}

657

677

658

ret = init_gnutls_session(&session);

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);

659

711

if(ret != 0){

660

712

return -1;

661

713

}

662

714

663

715

if(debug){

664

716

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

665

PRIu16 "\n", ip, port);

717

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

666

718

}

667

719

668

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

680

732

681

733

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

682

734

if(af == AF_INET6){

683

to.in6.sin6_family = (sa_family_t)af;

684

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

735

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

736

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

685

737

} else { /* IPv4 */

686

to.in.sin_family = (sa_family_t)af;

687

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

738

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

739

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

688

740

}

689

741

if(ret < 0 ){

690

742

int e = errno;

699

751

goto mandos_end;

700

752

}

701

753

if(af == AF_INET6){

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*/

754

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

755

if(IN6_IS_ADDR_LINKLOCAL

756

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

709

757

if(if_index == AVAHI_IF_UNSPEC){

710

758

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

711

759

" incomplete without a network interface\n");

713

761

goto mandos_end;

714

762

}

715

763

/* Set the network interface number as scope */

716

to.in6.sin6_scope_id = (uint32_t)if_index;

764

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

717

765

}

718

766

} else {

719

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

720

-Wconversion and

721

-Wunreachable-code */

767

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

722

768

}

723

769

724

770

if(quit_now){

732

778

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

733

779

perror_plus("if_indextoname");

734

780

} else {

735

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

736

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

781

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

782

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

737

783

}

738

784

} else {

739

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

740

ip, port);

785

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

786

ip, (uintmax_t)port);

741

787

}

742

788

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

743

789

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

744

const char *pcret;

745

790

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

791

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

792

sizeof(struct sockaddr_in6),

793

addrstr, sizeof(addrstr), NULL, 0,

794

NI_NUMERICHOST);

748

795

} else {

749

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

750

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

751

800

}

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

}

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);

758

807

}

759

808

}

760

809

764

813

}

765

814

766

815

if(af == AF_INET6){

767

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

816

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

817

sizeof(struct sockaddr_in6));

768

818

} else {

769

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

819

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

820

sizeof(struct sockaddr_in));

770

821

}

771

822

if(ret < 0){

772

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

823

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

773

824

int e = errno;

774

825

perror_plus("connect");

775

826

errno = e;

821

872

goto mandos_end;

822

873

}

823

874

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

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);

826

880

827

881

if(quit_now){

828

882

errno = EINTR;

933

987

if(buffer_length > 0){

934

988

ssize_t decrypted_buffer_size;

935

989

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

936

&decrypted_buffer);

990

&decrypted_buffer, mc);

937

991

if(decrypted_buffer_size >= 0){

938

992

939

993

written = 0;

987

1041

return retval;

988

1042

}

989

1043

1044

__attribute__((nonnull))

990

1045

static void resolve_callback(AvahiSServiceResolver *r,

991

1046

AvahiIfIndex interface,

992

1047

AvahiProtocol proto,

1000

1055

AVAHI_GCC_UNUSED AvahiStringList *txt,

1001

1056

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1002

1057

flags,

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1058

void *mc){

1059

if(r == NULL){

1060

return;

1061

}

1005

1062

1006

1063

/* Called whenever a service has been resolved successfully or

1007

1064

timed out */

1016

1073

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

1017

1074

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

1018

1075

domain,

1019

avahi_strerror(avahi_server_errno(mc.server)));

1076

avahi_strerror(avahi_server_errno

1077

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

1020

1078

break;

1021

1079

1022

1080

case AVAHI_RESOLVER_FOUND:

1028

1086

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

1029

1087

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

1030

1088

}

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1089

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

1090

interface,

1091

avahi_proto_to_af(proto),

1092

mc);

1033

1093

if(ret == 0){

1034

avahi_simple_poll_quit(mc.simple_poll);

1094

avahi_simple_poll_quit(simple_poll);

1035

1095

} else {

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1096

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

1097

avahi_proto_to_af(proto),

1098

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

1038

1099

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

1039

1100

" list\n", name);

1040

1101

}

1053

1114

const char *domain,

1054

1115

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1055

1116

flags,

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1117

void *mc){

1118

if(b == NULL){

1119

return;

1120

}

1058

1121

1059

1122

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

1060

1123

is removed from the LAN */

1068

1131

case AVAHI_BROWSER_FAILURE:

1069

1132

1070

1133

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

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1134

avahi_strerror(avahi_server_errno

1135

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

1136

avahi_simple_poll_quit(simple_poll);

1073

1137

return;

1074

1138

1075

1139

case AVAHI_BROWSER_NEW:

1078

1142

the callback function is called the Avahi server will free the

1079

1143

resolver for us. */

1080

1144

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

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)

1084

1149

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

1085

1150

" %s\n", name,

1086

avahi_strerror(avahi_server_errno(mc.server)));

1151

avahi_strerror(avahi_server_errno

1152

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

1087

1153

break;

1088

1154

1089

1155

case AVAHI_BROWSER_REMOVE:

1108

1174

signal_received = sig;

1109

1175

int old_errno = errno;

1110

1176

/* set main loop to exit */

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1177

if(simple_poll != NULL){

1178

avahi_simple_poll_quit(simple_poll);

1113

1179

}

1114

1180

errno = old_errno;

1115

1181

}

1116

1182

1183

__attribute__((nonnull, warn_unused_result))

1117

1184

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

1118

1185

int ret;

1186

error_t ret_errno;

1119

1187

1120

1188

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

1121

1189

if(s < 0){

1190

ret_errno = errno;

1122

1191

perror_plus("socket");

1192

errno = ret_errno;

1123

1193

return false;

1124

1194

}

1125

1195

strcpy(ifr->ifr_name, ifname);

1126

1196

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1127

1197

if(ret == -1){

1128

1198

if(debug){

1199

ret_errno = errno;

1129

1200

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1130

1202

}

1131

1203

return false;

1132

1204

}

1133

1205

return true;

1134

1206

}

1135

1207

1208

__attribute__((nonnull, warn_unused_result))

1136

1209

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

1137

1210

1138

1211

/* Reject the loopback device */

1180

1253

* corresponds to an acceptable network device.

1181

1254

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

1182

1255

*/

1256

__attribute__((nonnull, warn_unused_result))

1183

1257

int good_interface(const struct dirent *if_entry){

1184

1258

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

1185

1259

return 0;

1201

1275

}

1202

1276

1203

1277

/*

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

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))

1246

1312

int notdotentries(const struct dirent *direntry){

1247

1313

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

1248

1314

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

1255

1321

}

1256

1322

1257

1323

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

1324

__attribute__((nonnull, warn_unused_result))

1258

1325

int runnable_hook(const struct dirent *direntry){

1259

1326

int ret;

1260

1327

size_t sret;

1315

1382

return 1;

1316

1383

}

1317

1384

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1385

__attribute__((nonnull, warn_unused_result))

1386

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1387

mandos_context *mc){

1319

1388

int ret;

1320

1389

struct timespec now;

1321

1390

struct timespec waited_time;

1322

1391

intmax_t block_time;

1323

1392

1324

1393

while(true){

1325

if(mc.current_server == NULL){

1326

if (debug){

1394

if(mc->current_server == NULL){

1395

if(debug){

1327

1396

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

1328

1397

" No timeout!\n");

1329

1398

}

1330

1399

ret = avahi_simple_poll_iterate(s, -1);

1331

1400

} else {

1332

if (debug){

1401

if(debug){

1333

1402

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

1334

1403

" it, or wait\n");

1335

1404

}

1342

1411

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

1343

1412

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

1344

1413

waited_time.tv_sec = (now.tv_sec

1345

- mc.current_server->last_seen.tv_sec);

1414

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

1346

1415

waited_time.tv_nsec = (now.tv_nsec

1347

- mc.current_server->last_seen.tv_nsec);

1416

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

1348

1417

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

1349

1418

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

1350

1419

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

1352

1421

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

1353

1422

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

1354

1423

1355

if (debug){

1424

if(debug){

1356

1425

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

1357

1426

block_time);

1358

1427

}

1359

1428

1360

1429

if(block_time <= 0){

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);

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);

1365

1434

if(ret == 0){

1366

avahi_simple_poll_quit(mc.simple_poll);

1435

avahi_simple_poll_quit(s);

1367

1436

return 0;

1368

1437

}

1369

1438

ret = clock_gettime(CLOCK_MONOTONIC,

1370

&mc.current_server->last_seen);

1439

&mc->current_server->last_seen);

1371

1440

if(ret == -1){

1372

1441

perror_plus("clock_gettime");

1373

1442

return -1;

1374

1443

}

1375

mc.current_server = mc.current_server->next;

1444

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

1376

1445

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

1377

1446

servers, but don't block */

1378

1447

}

1380

1449

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

1381

1450

}

1382

1451

if(ret != 0){

1383

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

1452

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

1384

1453

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

1385

1454

}

1386

1455

}

1387

1456

}

1388

1457

}

1389

1458

1390

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

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,

1391

1517

const float delay){

1392

1518

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

1519

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

1396

1520

alphasort);

1397

1521

if(numhooks == -1){

1398

perror_plus("scandir");

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

}

1399

1530

} else {

1531

struct dirent *direntry;

1532

int ret;

1400

1533

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

1401

1534

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

1402

1535

direntry = direntries[i];

1414

1547

if(hook_pid == 0){

1415

1548

/* Child */

1416

1549

/* Raise privileges */

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");

1550

if(raise_privileges_permanently() != 0){

1551

perror_plus("Failed to raise privileges");

1552

_exit(EX_NOPERM);

1427

1553

}

1428

1554

/* Set group */

1429

1555

errno = 0;

1430

1556

ret = setgid(0);

1431

1557

if(ret == -1){

1432

1558

perror_plus("setgid");

1559

_exit(EX_NOPERM);

1433

1560

}

1434

1561

/* Reset supplementary groups */

1435

1562

errno = 0;

1436

1563

ret = setgroups(0, NULL);

1437

1564

if(ret == -1){

1438

1565

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

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

}

1443

1583

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

1444

1584

if(ret == -1){

1445

1585

perror_plus("setenv");

1461

1601

_exit(EX_OSERR);

1462

1602

}

1463

1603

char *delaystring;

1464

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

1604

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

1465

1605

if(ret == -1){

1466

1606

perror_plus("asprintf");

1467

1607

_exit(EX_OSERR);

1520

1660

}

1521

1661

close(devnull);

1522

1662

}

1523

return true;

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;

1524

1863

}

1525

1864

1526

1865

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 };

1527

1870

AvahiSServiceBrowser *sb = NULL;

1528

int error;

1871

error_t ret_errno;

1529

1872

int ret;

1530

1873

intmax_t tmpmax;

1531

1874

char *tmp;

1532

1875

int exitcode = EXIT_SUCCESS;

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;

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;

1541

1881

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1542

1882

const char *seckey = PATHDIR "/" SECKEY;

1543

1883

const char *pubkey = PATHDIR "/" PUBKEY;

1884

char *interfaces_hooks = NULL;

1544

1885

1545

1886

bool gnutls_initialized = false;

1546

1887

bool gpgme_initialized = false;

1637

1978

connect_to = arg;

1638

1979

break;

1639

1980

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

1640

interface = arg;

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

}

1641

1986

break;

1642

1987

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

1643

1988

seckey = arg;

1720

2065

/* Work around Debian bug #633582:

1721

2066

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

1722

2067

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

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");

1728

2073

} else {

1729

2074

struct stat st;

1730

2075

1771

2116

}

1772

2117

1773

2118

/* Lower privileges */

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

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;

1778

2140

}

1779

2141

}

1780

2142

}

1781

2143

1782

2144

/* Run network hooks */

1783

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

1784

goto end;

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);

1785

2157

}

1786

2158

1787

2159

if(not debug){

1788

2160

avahi_set_log_function(empty_log);

1789

2161

}

1790

2162

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

1823

2163

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

1824

2164

from the signal handler */

1825

2165

/* Initialize the pseudo-RNG for Avahi */

1826

2166

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

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2167

simple_poll = avahi_simple_poll_new();

2168

if(simple_poll == NULL){

1829

2169

fprintf_plus(stderr,

1830

2170

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

1831

2171

exitcode = EX_UNAVAILABLE;

1895

2235

}

1896

2236

}

1897

2237

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");

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;

1983

2285

}

1984

2286

}

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){

2002

2287

break;

2003

2288

}

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

}

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);

2033

2316

}

2034

2317

2035

2318

if(quit_now){

2036

2319

goto end;

2037

2320

}

2038

2321

2039

ret = init_gnutls_global(pubkey, seckey);

2322

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

2040

2323

if(ret == -1){

2041

2324

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

2042

2325

exitcode = EX_UNAVAILABLE;

2049

2332

goto end;

2050

2333

}

2051

2334

2052

if(mkdtemp(tempdir) == NULL){

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){

2053

2345

perror_plus("mkdtemp");

2054

2346

goto end;

2055

2347

}

2056

tempdir_created = true;

2057

2348

2058

2349

if(quit_now){

2059

2350

goto end;

2060

2351

}

2061

2352

2062

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

2353

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

2063

2354

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

2064

2355

exitcode = EX_UNAVAILABLE;

2065

2356

goto end;

2075

2366

/* Connect directly, do not use Zeroconf */

2076

2367

/* (Mainly meant for debugging) */

2077

2368

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

2369

2078

2370

if(address == NULL){

2079

2371

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

2080

2372

exitcode = EX_USAGE;

2085

2377

goto end;

2086

2378

}

2087

2379

2088

uint16_t port;

2380

in_port_t port;

2089

2381

errno = 0;

2090

2382

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

2091

2383

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

2092

or tmpmax != (uint16_t)tmpmax){

2384

or tmpmax != (in_port_t)tmpmax){

2093

2385

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

2094

2386

exitcode = EX_USAGE;

2095

2387

goto end;

2096

2388

}

2097

2389

2098

2390

if(quit_now){

2099

2391

goto end;

2100

2392

}

2101

2393

2102

port = (uint16_t)tmpmax;

2394

port = (in_port_t)tmpmax;

2103

2395

*address = '\0';

2104

2396

/* Colon in address indicates IPv6 */

2105

2397

int af;

2121

2413

}

2122

2414

2123

2415

while(not quit_now){

2124

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

2416

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

2417

&mc);

2125

2418

if(quit_now or ret == 0){

2126

2419

break;

2127

2420

}

2129

2422

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

2130

2423

(int)retry_interval);

2131

2424

}

2132

sleep((int)retry_interval);

2425

sleep((unsigned int)retry_interval);

2133

2426

}

2134

2427

2135

if (not quit_now){

2428

if(not quit_now){

2136

2429

exitcode = EXIT_SUCCESS;

2137

2430

}

2138

2431

2153

2446

config.publish_domain = 0;

2154

2447

2155

2448

/* Allocate a new server */

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

2449

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2450

&config, NULL, NULL, &ret_errno);

2159

2451

2160

2452

/* Free the Avahi configuration data */

2161

2453

avahi_server_config_free(&config);

2164

2456

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

2165

2457

if(mc.server == NULL){

2166

2458

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

2167

avahi_strerror(error));

2459

avahi_strerror(ret_errno));

2168

2460

exitcode = EX_UNAVAILABLE;

2169

2461

goto end;

2170

2462

}

2176

2468

/* Create the Avahi service browser */

2177

2469

sb = avahi_s_service_browser_new(mc.server, if_index,

2178

2470

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2179

NULL, 0, browse_callback, NULL);

2471

NULL, 0, browse_callback,

2472

(void *)&mc);

2180

2473

if(sb == NULL){

2181

2474

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

2182

2475

avahi_strerror(avahi_server_errno(mc.server)));

2194

2487

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

2195

2488

}

2196

2489

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

2490

ret = avahi_loop_with_timeout(simple_poll,

2491

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

2199

2492

if(debug){

2200

2493

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

2201

2494

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

2208

2501

}

2209

2502

2210

2503

/* Cleanup things */

2504

free(mc.interfaces);

2505

2211

2506

if(sb != NULL)

2212

2507

avahi_s_service_browser_free(sb);

2213

2508

2214

2509

if(mc.server != NULL)

2215

2510

avahi_server_free(mc.server);

2216

2511

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

2512

if(simple_poll != NULL)

2513

avahi_simple_poll_free(simple_poll);

2219

2514

2220

2515

if(gnutls_initialized){

2221

2516

gnutls_certificate_free_credentials(mc.cred);

2238

2533

}

2239

2534

}

2240

2535

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

2536

/* Re-raise privileges */

2245

2537

{

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

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

}

2250

2564

}

2251

2565

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

}

2566

ret_errno = lower_privileges_permanently();

2567

if(ret_errno != 0){

2568

perror_plus("Failed to lower privileges permanently");

2268

2569

}

2269

2570

}

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2571

2572

free(interfaces_to_take_down);

2573

free(interfaces_hooks);

2276

2574

2277

2575

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

2278

if(tempdir_created){

2576

if(tempdir != NULL){

2279

2577

struct dirent **direntries = NULL;

2280

2578

struct dirent *direntry = NULL;

2281

2579

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

2282

2580

alphasort);

2283

if (numentries > 0){

2581

if(numentries > 0){

2284

2582

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

2285

2583

direntry = direntries[i];

2286

2584

char *fullname = NULL;

2301

2599

2302

2600

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

2303

2601

free(direntries);

2304

if (numentries == -1){

2602

if(numentries == -1){

2305

2603

perror_plus("scandir");

2306

2604

}

2307

2605

ret = rmdir(tempdir);