/mandos/release : revision 284

62

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

63

strtoimax() */

64

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

65

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

65

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

66

program_invocation_short_name */

66

67

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

67

68

#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,

68

69

SIOCSIFFLAGS, if_indextoname(),

73

74

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

74

75

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

75

76

setgid(), pause() */

76

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

77

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

77

78

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

78

79

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

79

80

argp_state, struct argp,

130

131

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

131

132

char *connect_to = NULL;

132

133

134

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

135

typedef struct server{

136

const char *ip;

137

uint16_t port;

138

AvahiIfIndex if_index;

139

int af;

140

struct timespec last_seen;

141

struct server *next;

142

struct server *prev;

143

} server;

144

133

145

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

134

146

typedef struct {

135

147

AvahiSimplePoll *simple_poll;

139

151

gnutls_dh_params_t dh_params;

140

152

const char *priority;

141

153

gpgme_ctx_t ctx;

154

server *current_server;

142

155

} mandos_context;

143

156

144

157

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

145

158

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

146

159

.dh_bits = 1024, .priority = "SECURE256"

147

":!CTYPE-X.509:+CTYPE-OPENPGP" };

160

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

161

.current_server = NULL };

148

162

149

163

sig_atomic_t quit_now = 0;

150

164

int signal_received = 0;

151

165

166

/* Function to use when printing errors */

167

void perror_plus(const char *print_text){

168

fprintf(stderr, "Mandos plugin %s: ",

169

program_invocation_short_name);

170

perror(print_text);

171

}

172

152

173

/*

153

174

* Make additional room in "buffer" for at least BUFFER_SIZE more

154

175

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

166

187

return buffer_capacity;

167

188

}

168

189

190

int add_server(const char *ip, uint16_t port,

191

AvahiIfIndex if_index,

192

int af){

193

int ret;

194

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

195

if(new_server == NULL){

196

perror_plus("malloc");

197

return -1;

198

}

199

*new_server = (server){ .ip = strdup(ip),

200

.port = port,

201

.if_index = if_index,

202

.af = af };

203

if(new_server->ip == NULL){

204

perror_plus("strdup");

205

return -1;

206

}

207

/* unique case of first server */

208

if (mc.current_server == NULL){

209

new_server->next = new_server;

210

new_server->prev = new_server;

211

mc.current_server = new_server;

212

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

213

} else {

214

new_server->next = mc.current_server;

215

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

216

new_server->prev->next = new_server;

217

mc.current_server->prev = new_server;

218

}

219

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

220

if(ret == -1){

221

perror_plus("clock_gettime");

222

return -1;

223

}

224

return 0;

225

}

226

169

227

/*

170

228

* Initialize GPGME.

171

229

*/

185

243

186

244

fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

187

245

if(fd == -1){

188

perror("open");

246

perror_plus("open");

189

247

return false;

190

248

}

191

249

205

263

206

264

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

207

265

if(ret == -1){

208

perror("close");

266

perror_plus("close");

209

267

}

210

268

gpgme_data_release(pgp_data);

211

269

return true;

336

394

337

395

/* Seek back to the beginning of the GPGME plaintext data buffer */

338

396

if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){

339

perror("gpgme_data_seek");

397

perror_plus("gpgme_data_seek");

340

398

plaintext_length = -1;

341

399

goto decrypt_end;

342

400

}

347

405

(size_t)plaintext_length,

348

406

plaintext_capacity);

349

407

if(plaintext_capacity == 0){

350

perror("incbuffer");

408

perror_plus("incbuffer");

351

409

plaintext_length = -1;

352

410

goto decrypt_end;

353

411

}

360

418

break;

361

419

}

362

420

if(ret < 0){

363

perror("gpgme_data_read");

421

perror_plus("gpgme_data_read");

364

422

plaintext_length = -1;

365

423

goto decrypt_end;

366

424

}

423

481

}

424

482

425

483

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

484

ret = gnutls_certificate_allocate_credentials(&mc.cred);

427

485

if(ret != GNUTLS_E_SUCCESS){

428

fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning

429

from

430

-Wunreachable-code

431

*/

486

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

432

487

safer_gnutls_strerror(ret));

433

488

gnutls_global_deinit();

434

489

return -1;

589

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

645

if(tcp_sd < 0){

591

646

int e = errno;

592

perror("socket");

647

perror_plus("socket");

593

648

errno = e;

594

649

goto mandos_end;

595

650

}

609

664

}

610

665

if(ret < 0 ){

611

666

int e = errno;

612

perror("inet_pton");

667

perror_plus("inet_pton");

613

668

errno = e;

614

669

goto mandos_end;

615

670

}

651

706

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

652

707

char interface[IF_NAMESIZE];

653

708

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

654

perror("if_indextoname");

709

perror_plus("if_indextoname");

655

710

} else {

656

711

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

657

712

ip, interface, port);

671

726

sizeof(addrstr));

672

727

}

673

728

if(pcret == NULL){

674

perror("inet_ntop");

729

perror_plus("inet_ntop");

675

730

} else {

676

731

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

677

732

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

692

747

if(ret < 0){

693

748

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

694

749

int e = errno;

695

perror("connect");

750

perror_plus("connect");

696

751

errno = e;

697

752

}

698

753

goto mandos_end;

711

766

out_size - written));

712

767

if(ret == -1){

713

768

int e = errno;

714

perror("write");

769

perror_plus("write");

715

770

errno = e;

716

771

goto mandos_end;

717

772

}

742

797

goto mandos_end;

743

798

}

744

799

800

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

745

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

746

802

747

803

if(quit_now){

784

840

buffer_capacity);

785

841

if(buffer_capacity == 0){

786

842

int e = errno;

787

perror("incbuffer");

843

perror_plus("incbuffer");

788

844

errno = e;

789

845

goto mandos_end;

790

846

}

895

951

if(e == 0){

896

952

e = errno;

897

953

}

898

perror("close");

954

perror_plus("close");

899

955

}

900

956

gnutls_deinit(session);

957

errno = e;

901

958

if(quit_now){

902

e = EINTR;

959

errno = EINTR;

903

960

retval = -1;

904

961

}

905

errno = e;

906

962

}

907

963

return retval;

908

964

}

951

1007

avahi_proto_to_af(proto));

952

1008

if(ret == 0){

953

1009

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

954

1013

}

955

1014

}

956

1015

}

1010

1069

}

1011

1070

}

1012

1071

1013

/* stop main loop after sigterm has been called */

1072

/* Signal handler that stops main loop after SIGTERM */

1014

1073

static void handle_sigterm(int sig){

1015

1074

if(quit_now){

1016

1075

return;

1018

1077

quit_now = 1;

1019

1078

signal_received = sig;

1020

1079

int old_errno = errno;

1080

/* set main loop to exit */

1021

1081

if(mc.simple_poll != NULL){

1022

1082

avahi_simple_poll_quit(mc.simple_poll);

1023

1083

}

1032

1092

int good_interface(const struct dirent *if_entry){

1033

1093

ssize_t ssret;

1034

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

1035

1098

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1036

1099

if_entry->d_name);

1037

1100

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

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

1101

perror_plus("asprintf");

1042

1102

return 0;

1043

1103

}

1044

1104

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1045

1105

if(flags_fd == -1){

1046

perror("open");

1106

perror_plus("open");

1107

free(flagname);

1047

1108

return 0;

1048

1109

}

1110

free(flagname);

1049

1111

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1050

1112

/* read line from flags_fd */

1051

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1113

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1052

1114

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1053

1115

flagstring[(size_t)to_read] = '\0';

1054

1116

if(flagstring == NULL){

1055

perror("malloc");

1117

perror_plus("malloc");

1056

1118

close(flags_fd);

1057

1119

return 0;

1058

1120

}

1060

1122

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1061

1123

(size_t)to_read));

1062

1124

if(ssret == -1){

1063

perror("read");

1125

perror_plus("read");

1064

1126

free(flagstring);

1065

1127

close(flags_fd);

1066

1128

return 0;

1111

1173

}

1112

1174

return 0;

1113

1175

}

1176

/* Reject non-ARP interfaces (including dummy interfaces) */

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1114

1184

/* Accept this device */

1115

1185

if(debug){

1116

1186

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1119

1189

return 1;

1120

1190

}

1121

1191

1192

int notdotentries(const struct dirent *direntry){

1193

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

1194

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

1195

and (direntry->d_name[1] == '\0'

1196

or (direntry->d_name[1] == '.'

1197

and direntry->d_name[2] == '\0'))){

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1204

int ret;

1205

struct timespec now;

1206

struct timespec waited_time;

1207

intmax_t block_time;

1208

1209

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

fprintf(stderr,

1213

"Wait until first server is found. No timeout!\n");

1214

}

1215

ret = avahi_simple_poll_iterate(s, -1);

1216

} else {

1217

if (debug){

1218

fprintf(stderr, "Check current_server if we should run it,"

1219

" or wait\n");

1220

}

1221

/* the current time */

1222

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1223

if(ret == -1){

1224

perror_plus("clock_gettime");

1225

return -1;

1226

}

1227

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

1228

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

1229

waited_time.tv_sec = (now.tv_sec

1230

- mc.current_server->last_seen.tv_sec);

1231

waited_time.tv_nsec = (now.tv_nsec

1232

- mc.current_server->last_seen.tv_nsec);

1233

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

1234

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

1235

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

1236

block_time = ((retry_interval

1237

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

1238

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

1239

1240

if (debug){

1241

fprintf(stderr, "Blocking for %ld ms\n", block_time);

1242

}

1243

1244

if(block_time <= 0){

1245

ret = start_mandos_communication(mc.current_server->ip,

1246

mc.current_server->port,

1247

mc.current_server->if_index,

1248

mc.current_server->af);

1249

if(ret == 0){

1250

avahi_simple_poll_quit(mc.simple_poll);

1251

return 0;

1252

}

1253

ret = clock_gettime(CLOCK_MONOTONIC,

1254

&mc.current_server->last_seen);

1255

if(ret == -1){

1256

perror_plus("clock_gettime");

1257

return -1;

1258

}

1259

mc.current_server = mc.current_server->next;

1260

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

1261

servers, but don't block */

1262

}

1263

1264

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

1265

}

1266

if(ret != 0){

1267

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

1268

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

1269

}

1270

}

1271

}

1272

}

1273

1122

1274

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

1123

1275

AvahiSServiceBrowser *sb = NULL;

1124

1276

int error;

1141

1293

bool gnutls_initialized = false;

1142

1294

bool gpgme_initialized = false;

1143

1295

float delay = 2.5f;

1296

double retry_interval = 10; /* 10s between trying a server and

1297

retrying the same server again */

1144

1298

1145

1299

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1300

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1306

errno = 0;

1153

1307

ret = setgid(gid);

1154

1308

if(ret == -1){

1155

perror("setgid");

1309

perror_plus("setgid");

1156

1310

}

1157

1311

1158

1312

/* Lower user privileges (temporarily) */

1159

1313

errno = 0;

1160

1314

ret = seteuid(uid);

1161

1315

if(ret == -1){

1162

perror("seteuid");

1316

perror_plus("seteuid");

1163

1317

}

1164

1318

1165

1319

if(quit_now){

1200

1354

.arg = "SECONDS",

1201

1355

.doc = "Maximum delay to wait for interface startup",

1202

1356

.group = 2 },

1357

{ .name = "retry", .key = 132,

1358

.arg = "SECONDS",

1359

.doc = "Retry interval used when denied by the mandos server",

1360

.group = 2 },

1203

1361

/*

1204

1362

* These reproduce what we would get without ARGP_NO_HELP

1205

1363

*/

1249

1407

if(errno != 0 or tmp == arg or *tmp != '\0'){

1250

1408

argp_error(state, "Bad delay");

1251

1409

}

1410

case 132: /* --retry */

1411

errno = 0;

1412

retry_interval = strtod(arg, &tmp);

1413

if(errno != 0 or tmp == arg or *tmp != '\0'

1414

or (retry_interval * 1000) > INT_MAX){

1415

argp_error(state, "Bad retry interval");

1416

}

1252

1417

break;

1253

1418

/*

1254

1419

* These reproduce what we would get without ARGP_NO_HELP

1282

1447

case ENOMEM:

1283

1448

default:

1284

1449

errno = ret;

1285

perror("argp_parse");

1450

perror_plus("argp_parse");

1286

1451

exitcode = EX_OSERR;

1287

1452

goto end;

1288

1453

case EINVAL:

1290

1455

goto end;

1291

1456

}

1292

1457

}

1458

1459

{

1460

/* Work around Debian bug #633582:

1461

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

1462

struct stat st;

1463

1464

/* Re-raise priviliges */

1465

errno = 0;

1466

ret = seteuid(0);

1467

if(ret == -1){

1468

perror_plus("seteuid");

1469

}

1470

1471

int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);

1472

if(seckey_fd == -1){

1473

perror_plus("open");

1474

} else {

1475

ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));

1476

if(ret == -1){

1477

perror_plus("fstat");

1478

} else {

1479

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1480

ret = fchown(seckey_fd, uid, gid);

1481

if(ret == -1){

1482

perror_plus("fchown");

1483

}

1484

}

1485

}

1486

TEMP_FAILURE_RETRY(close(seckey_fd));

1487

}

1488

1489

int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);

1490

if(pubkey_fd == -1){

1491

perror_plus("open");

1492

} else {

1493

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));

1494

if(ret == -1){

1495

perror_plus("fstat");

1496

} else {

1497

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1498

ret = fchown(pubkey_fd, uid, gid);

1499

if(ret == -1){

1500

perror_plus("fchown");

1501

}

1502

}

1503

}

1504

TEMP_FAILURE_RETRY(close(pubkey_fd));

1505

}

1506

1507

/* Lower privileges */

1508

errno = 0;

1509

ret = seteuid(uid);

1510

if(ret == -1){

1511

perror_plus("seteuid");

1512

}

1513

}

1293

1514

1294

1515

if(not debug){

1295

1516

avahi_set_log_function(empty_log);

1306

1527

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

1307

1528

}

1308

1529

if(interface == NULL){

1309

perror("malloc");

1530

perror_plus("malloc");

1310

1531

free(direntries);

1311

1532

exitcode = EXIT_FAILURE;

1312

1533

goto end;

1334

1555

sigemptyset(&sigterm_action.sa_mask);

1335

1556

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1336

1557

if(ret == -1){

1337

perror("sigaddset");

1558

perror_plus("sigaddset");

1338

1559

exitcode = EX_OSERR;

1339

1560

goto end;

1340

1561

}

1341

1562

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1342

1563

if(ret == -1){

1343

perror("sigaddset");

1564

perror_plus("sigaddset");

1344

1565

exitcode = EX_OSERR;

1345

1566

goto end;

1346

1567

}

1347

1568

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1348

1569

if(ret == -1){

1349

perror("sigaddset");

1570

perror_plus("sigaddset");

1350

1571

exitcode = EX_OSERR;

1351

1572

goto end;

1352

1573

}

1356

1577

*/

1357

1578

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1358

1579

if(ret == -1){

1359

perror("sigaction");

1580

perror_plus("sigaction");

1360

1581

return EX_OSERR;

1361

1582

}

1362

1583

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

1584

ret = sigaction(SIGINT, &sigterm_action, NULL);

1364

1585

if(ret == -1){

1365

perror("sigaction");

1586

perror_plus("sigaction");

1366

1587

exitcode = EX_OSERR;

1367

1588

goto end;

1368

1589

}

1369

1590

}

1370

1591

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1371

1592

if(ret == -1){

1372

perror("sigaction");

1593

perror_plus("sigaction");

1373

1594

return EX_OSERR;

1374

1595

}

1375

1596

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

1597

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1377

1598

if(ret == -1){

1378

perror("sigaction");

1599

perror_plus("sigaction");

1379

1600

exitcode = EX_OSERR;

1380

1601

goto end;

1381

1602

}

1382

1603

}

1383

1604

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1384

1605

if(ret == -1){

1385

perror("sigaction");

1606

perror_plus("sigaction");

1386

1607

return EX_OSERR;

1387

1608

}

1388

1609

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

1610

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1390

1611

if(ret == -1){

1391

perror("sigaction");

1612

perror_plus("sigaction");

1392

1613

exitcode = EX_OSERR;

1393

1614

goto end;

1394

1615

}

1411

1632

errno = 0;

1412

1633

ret = seteuid(0);

1413

1634

if(ret == -1){

1414

perror("seteuid");

1635

perror_plus("seteuid");

1415

1636

}

1416

1637

1417

1638

#ifdef __linux__

1421

1642

bool restore_loglevel = true;

1422

1643

if(ret == -1){

1423

1644

restore_loglevel = false;

1424

perror("klogctl");

1645

perror_plus("klogctl");

1425

1646

}

1426

1647

#endif /* __linux__ */

1427

1648

1428

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

1650

if(sd < 0){

1430

perror("socket");

1651

perror_plus("socket");

1431

1652

exitcode = EX_OSERR;

1432

1653

#ifdef __linux__

1433

1654

if(restore_loglevel){

1434

1655

ret = klogctl(7, NULL, 0);

1435

1656

if(ret == -1){

1436

perror("klogctl");

1657

perror_plus("klogctl");

1437

1658

}

1438

1659

}

1439

1660

#endif /* __linux__ */

1441

1662

errno = 0;

1442

1663

ret = seteuid(uid);

1443

1664

if(ret == -1){

1444

perror("seteuid");

1665

perror_plus("seteuid");

1445

1666

}

1446

1667

goto end;

1447

1668

}

1448

1669

strcpy(network.ifr_name, interface);

1449

1670

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

1450

1671

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1672

perror_plus("ioctl SIOCGIFFLAGS");

1452

1673

#ifdef __linux__

1453

1674

if(restore_loglevel){

1454

1675

ret = klogctl(7, NULL, 0);

1455

1676

if(ret == -1){

1456

perror("klogctl");

1677

perror_plus("klogctl");

1457

1678

}

1458

1679

}

1459

1680

#endif /* __linux__ */

1462

1683

errno = 0;

1463

1684

ret = seteuid(uid);

1464

1685

if(ret == -1){

1465

perror("seteuid");

1686

perror_plus("seteuid");

1466

1687

}

1467

1688

goto end;

1468

1689

}

1472

1693

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

1473

1694

if(ret == -1){

1474

1695

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1476

1697

exitcode = EX_OSERR;

1477

1698

#ifdef __linux__

1478

1699

if(restore_loglevel){

1479

1700

ret = klogctl(7, NULL, 0);

1480

1701

if(ret == -1){

1481

perror("klogctl");

1702

perror_plus("klogctl");

1482

1703

}

1483

1704

}

1484

1705

#endif /* __linux__ */

1486

1707

errno = 0;

1487

1708

ret = seteuid(uid);

1488

1709

if(ret == -1){

1489

perror("seteuid");

1710

perror_plus("seteuid");

1490

1711

}

1491

1712

goto end;

1492

1713

}

1493

1714

}

1494

/* sleep checking until interface is running */

1715

/* Sleep checking until interface is running.

1716

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

1495

1717

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

1496

1718

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

1497

1719

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1720

perror_plus("ioctl SIOCGIFFLAGS");

1499

1721

} else if(network.ifr_flags & IFF_RUNNING){

1500

1722

break;

1501

1723

}

1502

1724

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

1725

ret = nanosleep(&sleeptime, NULL);

1504

1726

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

1505

perror("nanosleep");

1727

perror_plus("nanosleep");

1506

1728

}

1507

1729

}

1508

1730

if(not take_down_interface){

1509

1731

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

1510

1732

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

1511

1733

if(ret == -1){

1512

perror("close");

1734

perror_plus("close");

1513

1735

}

1514

1736

}

1515

1737

#ifdef __linux__

1517

1739

/* Restores kernel loglevel to default */

1518

1740

ret = klogctl(7, NULL, 0);

1519

1741

if(ret == -1){

1520

perror("klogctl");

1742

perror_plus("klogctl");

1521

1743

}

1522

1744

}

1523

1745

#endif /* __linux__ */

1527

1749

/* Lower privileges */

1528

1750

ret = seteuid(uid);

1529

1751

if(ret == -1){

1530

perror("seteuid");

1752

perror_plus("seteuid");

1531

1753

}

1532

1754

} else {

1533

1755

/* Lower privileges permanently */

1534

1756

ret = setuid(uid);

1535

1757

if(ret == -1){

1536

perror("setuid");

1758

perror_plus("setuid");

1537

1759

}

1538

1760

}

1539

1761

}

1555

1777

goto end;

1556

1778

}

1557

1779

1780

if(mkdtemp(tempdir) == NULL){

1781

perror_plus("mkdtemp");

1782

goto end;

1783

}

1558

1784

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

1562

goto end;

1563

}

1564

1785

1565

1786

if(quit_now){

1566

1787

goto end;

1626

1847

if(quit_now or ret == 0){

1627

1848

break;

1628

1849

}

1629

sleep(15);

1850

sleep((int)retry_interval or 1);

1630

1851

};

1631

1852

1632

1853

if (not quit_now){

1690

1911

if(debug){

1691

1912

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

1692

1913

}

1693

1694

avahi_simple_poll_loop(mc.simple_poll);

1914

1915

ret = avahi_loop_with_timeout(mc.simple_poll,

1916

(int)(retry_interval * 1000));

1917

if(debug){

1918

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

1919

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

1920

}

1695

1921

1696

1922

end:

1697

1923

1718

1944

if(gpgme_initialized){

1719

1945

gpgme_release(mc.ctx);

1720

1946

}

1947

1948

/* Cleans up the circular linked list of Mandos servers the client

1949

has seen */

1950

if(mc.current_server != NULL){

1951

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

1952

while(mc.current_server != NULL){

1953

server *next = mc.current_server->next;

1954

free(mc.current_server);

1955

mc.current_server = next;

1956

}

1957

}

1721

1958

1722

1959

/* Take down the network interface */

1723

1960

if(take_down_interface){

1725

1962

errno = 0;

1726

1963

ret = seteuid(0);

1727

1964

if(ret == -1){

1728

perror("seteuid");

1965

perror_plus("seteuid");

1729

1966

}

1730

1967

if(geteuid() == 0){

1731

1968

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

1732

1969

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1970

perror_plus("ioctl SIOCGIFFLAGS");

1734

1971

} else if(network.ifr_flags & IFF_UP) {

1735

1972

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

1736

1973

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

1737

1974

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1975

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1739

1976

}

1740

1977

}

1741

1978

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

1742

1979

if(ret == -1){

1743

perror("close");

1980

perror_plus("close");

1744

1981

}

1745

1982

/* Lower privileges permanently */

1746

1983

errno = 0;

1747

1984

ret = setuid(uid);

1748

1985

if(ret == -1){

1749

perror("setuid");

1986

perror_plus("setuid");

1750

1987

}

1751

1988

}

1752

1989

}

1753

1990

1754

/* Removes the temp directory used by GPGME */

1991

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

1755

1992

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

and (direntry->d_name[1] == '\0'

1772

or (direntry->d_name[1] == '.'

1773

and direntry->d_name[2] == '\0'))){

1774

continue;

1775

}

1993

struct dirent **direntries = NULL;

1994

struct dirent *direntry = NULL;

1995

ret = scandir(tempdir, &direntries, notdotentries, alphasort);

1996

if (ret > 0){

1997

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

1998

direntry = direntries[i];

1776

1999

char *fullname = NULL;

1777

2000

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

1778

2001

direntry->d_name);

1779

2002

if(ret < 0){

1780

perror("asprintf");

2003

perror_plus("asprintf");

1781

2004

continue;

1782

2005

}

1783

2006

ret = remove(fullname);

1787

2010

}

1788

2011

free(fullname);

1789

2012

}

1790

closedir(d);

2013

}

2014

2015

/* need to be cleaned even if ret == 0 because man page doesn't

2016

specify */

2017

free(direntries);

2018

if (ret == -1){

2019

perror_plus("scandir");

1791

2020

}

1792

2021

ret = rmdir(tempdir);

1793

2022

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

1794

perror("rmdir");

2023

perror_plus("rmdir");

1795

2024

}

1796

2025

}

1797

2026

1802

2031

&old_sigterm_action,

1803

2032

NULL));

1804

2033

if(ret == -1){

1805

perror("sigaction");

2034

perror_plus("sigaction");

1806

2035

}

1807

2036

do {

1808

2037

ret = raise(signal_received);

1809

2038

} while(ret != 0 and errno == EINTR);

1810

2039

if(ret != 0){

1811

perror("raise");

2040

perror_plus("raise");

1812

2041

abort();

1813

2042

}

1814

2043

TEMP_FAILURE_RETRY(pause());