/mandos/release : revision 24.1.166

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

26

* along with this program. If not, see

27

* <http://www.gnu.org/licenses/>.

28

*

29

* Contact the authors at <mandos@recompile.se>.

29

* Contact the authors at <mandos@fukt.bsnet.se>.

30

*/

31

32

/* Needed by GPGME, specifically gpgme_data_seek() */

62

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

63

strtoimax() */

64

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

65

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

66

program_invocation_short_name */

65

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

67

66

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

68

67

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

69

68

SIOCSIFFLAGS, if_indextoname(),

74

73

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

75

74

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

76

75

setgid(), pause() */

77

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

76

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

78

77

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

79

78

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

80

79

argp_state, struct argp,

127

126

bool debug = false;

128

127

static const char mandos_protocol_version[] = "1";

129

128

const char *argp_program_version = "mandos-client " VERSION;

130

const char *argp_program_bug_address = "<mandos@recompile.se>";

129

const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";

131

130

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

132

131

char *connect_to = NULL;

133

132

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

145

133

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

146

134

typedef struct {

147

135

AvahiSimplePoll *simple_poll;

151

139

gnutls_dh_params_t dh_params;

152

140

const char *priority;

153

141

gpgme_ctx_t ctx;

154

server *current_server;

155

142

} mandos_context;

156

143

157

144

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

158

145

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

159

146

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

147

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

162

148

163

149

sig_atomic_t quit_now = 0;

164

150

int signal_received = 0;

165

151

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

173

152

/*

174

153

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

175

154

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

187

166

return buffer_capacity;

188

167

}

189

168

190

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

191

int add_server(const char *ip, uint16_t port,

192

AvahiIfIndex if_index,

193

int af){

194

int ret;

195

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

196

if(new_server == NULL){

197

perror_plus("malloc");

198

return -1;

199

}

200

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

201

.port = port,

202

.if_index = if_index,

203

.af = af };

204

if(new_server->ip == NULL){

205

perror_plus("strdup");

206

return -1;

207

}

208

/* Special case of first server */

209

if (mc.current_server == NULL){

210

new_server->next = new_server;

211

new_server->prev = new_server;

212

mc.current_server = new_server;

213

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

214

} else {

215

new_server->next = mc.current_server;

216

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

217

new_server->prev->next = new_server;

218

mc.current_server->prev = new_server;

219

}

220

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

221

if(ret == -1){

222

perror_plus("clock_gettime");

223

return -1;

224

}

225

return 0;

226

}

227

228

169

/*

229

170

* Initialize GPGME.

230

171

*/

244

185

245

186

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

246

187

if(fd == -1){

247

perror_plus("open");

188

perror("open");

248

189

return false;

249

190

}

250

191

264

205

265

206

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

266

207

if(ret == -1){

267

perror_plus("close");

208

perror("close");

268

209

}

269

210

gpgme_data_release(pgp_data);

270

211

return true;

283

224

return false;

284

225

}

285

226

286

/* Set GPGME home directory for the OpenPGP engine only */

227

/* Set GPGME home directory for the OpenPGP engine only */

287

228

rc = gpgme_get_engine_info(&engine_info);

288

229

if(rc != GPG_ERR_NO_ERROR){

289

230

fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",

395

336

396

337

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

397

338

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

398

perror_plus("gpgme_data_seek");

339

perror("gpgme_data_seek");

399

340

plaintext_length = -1;

400

341

goto decrypt_end;

401

342

}

406

347

(size_t)plaintext_length,

407

348

plaintext_capacity);

408

349

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

350

perror("incbuffer");

410

351

plaintext_length = -1;

411

352

goto decrypt_end;

412

353

}

419

360

break;

420

361

}

421

362

if(ret < 0){

422

perror_plus("gpgme_data_read");

363

perror("gpgme_data_read");

423

364

plaintext_length = -1;

424

365

goto decrypt_end;

425

366

}

482

423

}

483

424

484

425

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

426

gnutls_certificate_allocate_credentials(&mc.cred);

486

427

if(ret != GNUTLS_E_SUCCESS){

487

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

428

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

429

from

430

-Wunreachable-code

431

*/

488

432

safer_gnutls_strerror(ret));

489

433

gnutls_global_deinit();

490

434

return -1;

645

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

646

590

if(tcp_sd < 0){

647

591

int e = errno;

648

perror_plus("socket");

592

perror("socket");

649

593

errno = e;

650

594

goto mandos_end;

651

595

}

665

609

}

666

610

if(ret < 0 ){

667

611

int e = errno;

668

perror_plus("inet_pton");

612

perror("inet_pton");

669

613

errno = e;

670

614

goto mandos_end;

671

615

}

707

651

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

708

652

char interface[IF_NAMESIZE];

709

653

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

710

perror_plus("if_indextoname");

654

perror("if_indextoname");

711

655

} else {

712

656

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

713

657

ip, interface, port);

727

671

sizeof(addrstr));

728

672

}

729

673

if(pcret == NULL){

730

perror_plus("inet_ntop");

674

perror("inet_ntop");

731

675

} else {

732

676

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

733

677

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

748

692

if(ret < 0){

749

693

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

750

694

int e = errno;

751

perror_plus("connect");

695

perror("connect");

752

696

errno = e;

753

697

}

754

698

goto mandos_end;

767

711

out_size - written));

768

712

if(ret == -1){

769

713

int e = errno;

770

perror_plus("write");

714

perror("write");

771

715

errno = e;

772

716

goto mandos_end;

773

717

}

798

742

goto mandos_end;

799

743

}

800

744

801

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

802

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

803

746

804

747

if(quit_now){

841

784

buffer_capacity);

842

785

if(buffer_capacity == 0){

843

786

int e = errno;

844

perror_plus("incbuffer");

787

perror("incbuffer");

845

788

errno = e;

846

789

goto mandos_end;

847

790

}

952

895

if(e == 0){

953

896

e = errno;

954

897

}

955

perror_plus("close");

898

perror("close");

956

899

}

957

900

gnutls_deinit(session);

958

errno = e;

959

901

if(quit_now){

960

errno = EINTR;

902

e = EINTR;

961

903

retval = -1;

962

904

}

905

errno = e;

963

906

}

964

907

return retval;

965

908

}

1008

951

avahi_proto_to_af(proto));

1009

952

if(ret == 0){

1010

953

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1014

954

}

1015

955

}

1016

956

}

1070

1010

}

1071

1011

}

1072

1012

1073

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

1013

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

1074

1014

static void handle_sigterm(int sig){

1075

1015

if(quit_now){

1076

1016

return;

1078

1018

quit_now = 1;

1079

1019

signal_received = sig;

1080

1020

int old_errno = errno;

1081

/* set main loop to exit */

1082

1021

if(mc.simple_poll != NULL){

1083

1022

avahi_simple_poll_quit(mc.simple_poll);

1084

1023

}

1092

1031

*/

1093

1032

int good_interface(const struct dirent *if_entry){

1094

1033

ssize_t ssret;

1095

int ret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1096

1041

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

1097

1042

return 0;

1098

1043

}

1099

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

1100

if(s < 0){

1101

perror_plus("socket");

1102

return 0;

1103

}

1104

struct ifreq ifr;

1105

strcpy(ifr.ifr_name, if_entry->d_name);

1106

ret = ioctl(s, SIOCGIFFLAGS, &ifr);

1107

if(ret == -1){

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

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

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1070

break;

1071

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

tmpmax = strtoimax(flagstring, &tmp, 0);

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1108

1081

if(debug){

1109

perror_plus("ioctl SIOCGIFFLAGS");

1082

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1083

flagstring, if_entry->d_name);

1110

1084

}

1085

free(flagstring);

1111

1086

return 0;

1112

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1113

1090

/* Reject the loopback device */

1114

if(ifr.ifr_flags & IFF_LOOPBACK){

1091

if(flags & IFF_LOOPBACK){

1115

1092

if(debug){

1116

1093

fprintf(stderr, "Rejecting loopback interface \"%s\"\n",

1117

1094

if_entry->d_name);

1119

1096

return 0;

1120

1097

}

1121

1098

/* Accept point-to-point devices only if connect_to is specified */

1122

if(connect_to != NULL and (ifr.ifr_flags & IFF_POINTOPOINT)){

1099

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1123

1100

if(debug){

1124

1101

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1125

1102

if_entry->d_name);

1127

1104

return 1;

1128

1105

}

1129

1106

/* Otherwise, reject non-broadcast-capable devices */

1130

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

1107

if(not (flags & IFF_BROADCAST)){

1131

1108

if(debug){

1132

1109

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

1133

1110

if_entry->d_name);

1134

1111

}

1135

1112

return 0;

1136

1113

}

1137

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

1138

if(ifr.ifr_flags & IFF_NOARP){

1139

if(debug){

1140

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

1141

if_entry->d_name);

1142

}

1143

return 0;

1144

}

1145

1114

/* Accept this device */

1146

1115

if(debug){

1147

1116

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

1150

1119

return 1;

1151

1120

}

1152

1121

1153

int notdotentries(const struct dirent *direntry){

1154

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

1155

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

1156

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

1157

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

1158

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

1159

return 0;

1160

}

1161

return 1;

1162

}

1163

1164

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1165

int ret;

1166

struct timespec now;

1167

struct timespec waited_time;

1168

intmax_t block_time;

1169

1170

while(true){

1171

if(mc.current_server == NULL){

1172

if (debug){

1173

fprintf(stderr,

1174

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

1175

}

1176

ret = avahi_simple_poll_iterate(s, -1);

1177

} else {

1178

if (debug){

1179

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

1180

" or wait\n");

1181

}

1182

/* the current time */

1183

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1184

if(ret == -1){

1185

perror_plus("clock_gettime");

1186

return -1;

1187

}

1188

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

1189

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

1190

waited_time.tv_sec = (now.tv_sec

1191

- mc.current_server->last_seen.tv_sec);

1192

waited_time.tv_nsec = (now.tv_nsec

1193

- mc.current_server->last_seen.tv_nsec);

1194

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

1195

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

1196

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

1197

block_time = ((retry_interval

1198

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

1199

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

1200

1201

if (debug){

1202

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

1203

}

1204

1205

if(block_time <= 0){

1206

ret = start_mandos_communication(mc.current_server->ip,

1207

mc.current_server->port,

1208

mc.current_server->if_index,

1209

mc.current_server->af);

1210

if(ret == 0){

1211

avahi_simple_poll_quit(mc.simple_poll);

1212

return 0;

1213

}

1214

ret = clock_gettime(CLOCK_MONOTONIC,

1215

&mc.current_server->last_seen);

1216

if(ret == -1){

1217

perror_plus("clock_gettime");

1218

return -1;

1219

}

1220

mc.current_server = mc.current_server->next;

1221

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

1222

servers, but don't block */

1223

}

1224

1225

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

1226

}

1227

if(ret != 0){

1228

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

1229

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

1230

}

1231

}

1232

}

1233

}

1234

1235

1122

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

1236

1123

AvahiSServiceBrowser *sb = NULL;

1237

1124

int error;

1254

1141

bool gnutls_initialized = false;

1255

1142

bool gpgme_initialized = false;

1256

1143

float delay = 2.5f;

1257

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

1258

retrying the same server again */

1259

1144

1260

1145

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1261

1146

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1267

1152

errno = 0;

1268

1153

ret = setgid(gid);

1269

1154

if(ret == -1){

1270

perror_plus("setgid");

1155

perror("setgid");

1271

1156

}

1272

1157

1273

1158

/* Lower user privileges (temporarily) */

1274

1159

errno = 0;

1275

1160

ret = seteuid(uid);

1276

1161

if(ret == -1){

1277

perror_plus("seteuid");

1162

perror("seteuid");

1278

1163

}

1279

1164

1280

1165

if(quit_now){

1315

1200

.arg = "SECONDS",

1316

1201

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

1317

1202

.group = 2 },

1318

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

1319

.arg = "SECONDS",

1320

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

1321

.group = 2 },

1322

1203

/*

1323

1204

* These reproduce what we would get without ARGP_NO_HELP

1324

1205

*/

1368

1249

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

1369

1250

argp_error(state, "Bad delay");

1370

1251

}

1371

case 132: /* --retry */

1372

errno = 0;

1373

retry_interval = strtod(arg, &tmp);

1374

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

1375

or (retry_interval * 1000) > INT_MAX

1376

or retry_interval < 0){

1377

argp_error(state, "Bad retry interval");

1378

}

1379

1252

break;

1380

1253

/*

1381

1254

* These reproduce what we would get without ARGP_NO_HELP

1409

1282

case ENOMEM:

1410

1283

default:

1411

1284

errno = ret;

1412

perror_plus("argp_parse");

1285

perror("argp_parse");

1413

1286

exitcode = EX_OSERR;

1414

1287

goto end;

1415

1288

case EINVAL:

1417

1290

goto end;

1418

1291

}

1419

1292

}

1420

1421

{

1422

/* Work around Debian bug #633582:

1423

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

1424

struct stat st;

1425

1426

/* Re-raise priviliges */

1427

errno = 0;

1428

ret = seteuid(0);

1429

if(ret == -1){

1430

perror_plus("seteuid");

1431

}

1432

1433

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

1434

int seckey_fd = open(seckey, O_RDONLY);

1435

if(seckey_fd == -1){

1436

perror_plus("open");

1437

} else {

1438

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

1439

if(ret == -1){

1440

perror_plus("fstat");

1441

} else {

1442

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

1443

ret = fchown(seckey_fd, uid, gid);

1444

if(ret == -1){

1445

perror_plus("fchown");

1446

}

1447

}

1448

}

1449

TEMP_FAILURE_RETRY(close(seckey_fd));

1450

}

1451

}

1452

1453

if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){

1454

int pubkey_fd = open(pubkey, O_RDONLY);

1455

if(pubkey_fd == -1){

1456

perror_plus("open");

1457

} else {

1458

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

1459

if(ret == -1){

1460

perror_plus("fstat");

1461

} else {

1462

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

1463

ret = fchown(pubkey_fd, uid, gid);

1464

if(ret == -1){

1465

perror_plus("fchown");

1466

}

1467

}

1468

}

1469

TEMP_FAILURE_RETRY(close(pubkey_fd));

1470

}

1471

}

1472

1473

/* Lower privileges */

1474

errno = 0;

1475

ret = seteuid(uid);

1476

if(ret == -1){

1477

perror_plus("seteuid");

1478

}

1479

}

1480

1293

1481

1294

if(not debug){

1482

1295

avahi_set_log_function(empty_log);

1493

1306

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

1494

1307

}

1495

1308

if(interface == NULL){

1496

perror_plus("malloc");

1309

perror("malloc");

1497

1310

free(direntries);

1498

1311

exitcode = EXIT_FAILURE;

1499

1312

goto end;

1521

1334

sigemptyset(&sigterm_action.sa_mask);

1522

1335

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

1523

1336

if(ret == -1){

1524

perror_plus("sigaddset");

1337

perror("sigaddset");

1525

1338

exitcode = EX_OSERR;

1526

1339

goto end;

1527

1340

}

1528

1341

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

1529

1342

if(ret == -1){

1530

perror_plus("sigaddset");

1343

perror("sigaddset");

1531

1344

exitcode = EX_OSERR;

1532

1345

goto end;

1533

1346

}

1534

1347

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

1535

1348

if(ret == -1){

1536

perror_plus("sigaddset");

1349

perror("sigaddset");

1537

1350

exitcode = EX_OSERR;

1538

1351

goto end;

1539

1352

}

1543

1356

*/

1544

1357

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

1545

1358

if(ret == -1){

1546

perror_plus("sigaction");

1359

perror("sigaction");

1547

1360

return EX_OSERR;

1548

1361

}

1549

1362

if(old_sigterm_action.sa_handler != SIG_IGN){

1550

1363

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

1551

1364

if(ret == -1){

1552

perror_plus("sigaction");

1365

perror("sigaction");

1553

1366

exitcode = EX_OSERR;

1554

1367

goto end;

1555

1368

}

1556

1369

}

1557

1370

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

1558

1371

if(ret == -1){

1559

perror_plus("sigaction");

1372

perror("sigaction");

1560

1373

return EX_OSERR;

1561

1374

}

1562

1375

if(old_sigterm_action.sa_handler != SIG_IGN){

1563

1376

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

1564

1377

if(ret == -1){

1565

perror_plus("sigaction");

1378

perror("sigaction");

1566

1379

exitcode = EX_OSERR;

1567

1380

goto end;

1568

1381

}

1569

1382

}

1570

1383

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

1571

1384

if(ret == -1){

1572

perror_plus("sigaction");

1385

perror("sigaction");

1573

1386

return EX_OSERR;

1574

1387

}

1575

1388

if(old_sigterm_action.sa_handler != SIG_IGN){

1576

1389

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

1577

1390

if(ret == -1){

1578

perror_plus("sigaction");

1391

perror("sigaction");

1579

1392

exitcode = EX_OSERR;

1580

1393

goto end;

1581

1394

}

1598

1411

errno = 0;

1599

1412

ret = seteuid(0);

1600

1413

if(ret == -1){

1601

perror_plus("seteuid");

1414

perror("seteuid");

1602

1415

}

1603

1416

1604

1417

#ifdef __linux__

1608

1421

bool restore_loglevel = true;

1609

1422

if(ret == -1){

1610

1423

restore_loglevel = false;

1611

perror_plus("klogctl");

1424

perror("klogctl");

1612

1425

}

1613

1426

#endif /* __linux__ */

1614

1427

1615

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1616

1429

if(sd < 0){

1617

perror_plus("socket");

1430

perror("socket");

1618

1431

exitcode = EX_OSERR;

1619

1432

#ifdef __linux__

1620

1433

if(restore_loglevel){

1621

1434

ret = klogctl(7, NULL, 0);

1622

1435

if(ret == -1){

1623

perror_plus("klogctl");

1436

perror("klogctl");

1624

1437

}

1625

1438

}

1626

1439

#endif /* __linux__ */

1628

1441

errno = 0;

1629

1442

ret = seteuid(uid);

1630

1443

if(ret == -1){

1631

perror_plus("seteuid");

1444

perror("seteuid");

1632

1445

}

1633

1446

goto end;

1634

1447

}

1635

1448

strcpy(network.ifr_name, interface);

1636

1449

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

1637

1450

if(ret == -1){

1638

perror_plus("ioctl SIOCGIFFLAGS");

1451

perror("ioctl SIOCGIFFLAGS");

1639

1452

#ifdef __linux__

1640

1453

if(restore_loglevel){

1641

1454

ret = klogctl(7, NULL, 0);

1642

1455

if(ret == -1){

1643

perror_plus("klogctl");

1456

perror("klogctl");

1644

1457

}

1645

1458

}

1646

1459

#endif /* __linux__ */

1649

1462

errno = 0;

1650

1463

ret = seteuid(uid);

1651

1464

if(ret == -1){

1652

perror_plus("seteuid");

1465

perror("seteuid");

1653

1466

}

1654

1467

goto end;

1655

1468

}

1659

1472

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

1660

1473

if(ret == -1){

1661

1474

take_down_interface = false;

1662

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1663

1476

exitcode = EX_OSERR;

1664

1477

#ifdef __linux__

1665

1478

if(restore_loglevel){

1666

1479

ret = klogctl(7, NULL, 0);

1667

1480

if(ret == -1){

1668

perror_plus("klogctl");

1481

perror("klogctl");

1669

1482

}

1670

1483

}

1671

1484

#endif /* __linux__ */

1673

1486

errno = 0;

1674

1487

ret = seteuid(uid);

1675

1488

if(ret == -1){

1676

perror_plus("seteuid");

1489

perror("seteuid");

1677

1490

}

1678

1491

goto end;

1679

1492

}

1680

1493

}

1681

/* Sleep checking until interface is running.

1682

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

1494

/* sleep checking until interface is running */

1683

1495

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

1684

1496

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

1685

1497

if(ret == -1){

1686

perror_plus("ioctl SIOCGIFFLAGS");

1498

perror("ioctl SIOCGIFFLAGS");

1687

1499

} else if(network.ifr_flags & IFF_RUNNING){

1688

1500

break;

1689

1501

}

1690

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1691

1503

ret = nanosleep(&sleeptime, NULL);

1692

1504

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

1693

perror_plus("nanosleep");

1505

perror("nanosleep");

1694

1506

}

1695

1507

}

1696

1508

if(not take_down_interface){

1697

1509

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

1698

1510

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

1699

1511

if(ret == -1){

1700

perror_plus("close");

1512

perror("close");

1701

1513

}

1702

1514

}

1703

1515

#ifdef __linux__

1705

1517

/* Restores kernel loglevel to default */

1706

1518

ret = klogctl(7, NULL, 0);

1707

1519

if(ret == -1){

1708

perror_plus("klogctl");

1520

perror("klogctl");

1709

1521

}

1710

1522

}

1711

1523

#endif /* __linux__ */

1715

1527

/* Lower privileges */

1716

1528

ret = seteuid(uid);

1717

1529

if(ret == -1){

1718

perror_plus("seteuid");

1530

perror("seteuid");

1719

1531

}

1720

1532

} else {

1721

1533

/* Lower privileges permanently */

1722

1534

ret = setuid(uid);

1723

1535

if(ret == -1){

1724

perror_plus("setuid");

1536

perror("setuid");

1725

1537

}

1726

1538

}

1727

1539

}

1743

1555

goto end;

1744

1556

}

1745

1557

1558

tempdir_created = true;

1746

1559

if(mkdtemp(tempdir) == NULL){

1747

perror_plus("mkdtemp");

1560

tempdir_created = false;

1561

perror("mkdtemp");

1748

1562

goto end;

1749

1563

}

1750

tempdir_created = true;

1751

1564

1752

1565

if(quit_now){

1753

1566

goto end;

1795

1608

1796

1609

port = (uint16_t)tmpmax;

1797

1610

*address = '\0';

1611

address = connect_to;

1798

1612

/* Colon in address indicates IPv6 */

1799

1613

int af;

1800

if(strchr(connect_to, ':') != NULL){

1614

if(strchr(address, ':') != NULL){

1801

1615

af = AF_INET6;

1802

/* Accept [] around IPv6 address - see RFC 5952 */

1803

if(connect_to[0] == '[' and address[-1] == ']')

1804

{

1805

connect_to++;

1806

address[-1] = '\0';

1807

}

1808

1616

} else {

1809

1617

af = AF_INET;

1810

1618

}

1811

address = connect_to;

1812

1619

1813

1620

if(quit_now){

1814

1621

goto end;

1815

1622

}

1816

1623

1817

1624

while(not quit_now){

1818

1625

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

1819

1626

if(quit_now or ret == 0){

1820

1627

break;

1821

1628

}

1822

if(debug){

1823

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

1824

(int)retry_interval);

1825

}

1826

sleep((int)retry_interval);

1827

}

1828

1629

sleep(15);

1630

};

1631

1829

1632

if (not quit_now){

1830

1633

exitcode = EXIT_SUCCESS;

1831

1634

}

1887

1690

if(debug){

1888

1691

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

1889

1692

}

1890

1891

ret = avahi_loop_with_timeout(mc.simple_poll,

1892

(int)(retry_interval * 1000));

1893

if(debug){

1894

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

1895

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

1896

}

1693

1694

avahi_simple_poll_loop(mc.simple_poll);

1897

1695

1898

1696

end:

1899

1697

1920

1718

if(gpgme_initialized){

1921

1719

gpgme_release(mc.ctx);

1922

1720

}

1923

1924

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

1925

has seen */

1926

if(mc.current_server != NULL){

1927

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

1928

while(mc.current_server != NULL){

1929

server *next = mc.current_server->next;

1930

free(mc.current_server);

1931

mc.current_server = next;

1932

}

1933

}

1934

1721

1935

1722

/* Take down the network interface */

1936

1723

if(take_down_interface){

1938

1725

errno = 0;

1939

1726

ret = seteuid(0);

1940

1727

if(ret == -1){

1941

perror_plus("seteuid");

1728

perror("seteuid");

1942

1729

}

1943

1730

if(geteuid() == 0){

1944

1731

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

1945

1732

if(ret == -1){

1946

perror_plus("ioctl SIOCGIFFLAGS");

1733

perror("ioctl SIOCGIFFLAGS");

1947

1734

} else if(network.ifr_flags & IFF_UP) {

1948

1735

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

1949

1736

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

1950

1737

if(ret == -1){

1951

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1952

1739

}

1953

1740

}

1954

1741

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

1955

1742

if(ret == -1){

1956

perror_plus("close");

1743

perror("close");

1957

1744

}

1958

1745

/* Lower privileges permanently */

1959

1746

errno = 0;

1960

1747

ret = setuid(uid);

1961

1748

if(ret == -1){

1962

perror_plus("setuid");

1749

perror("setuid");

1963

1750

}

1964

1751

}

1965

1752

}

1966

1753

1967

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

1754

/* Removes the temp directory used by GPGME */

1968

1755

if(tempdir_created){

1969

struct dirent **direntries = NULL;

1970

struct dirent *direntry = NULL;

1971

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

1972

alphasort);

1973

if (numentries > 0){

1974

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

1975

direntry = direntries[i];

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

}

1976

1776

char *fullname = NULL;

1977

1777

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

1978

1778

direntry->d_name);

1979

1779

if(ret < 0){

1980

perror_plus("asprintf");

1780

perror("asprintf");

1981

1781

continue;

1982

1782

}

1983

1783

ret = remove(fullname);

1987

1787

}

1988

1788

free(fullname);

1989

1789

}

1990

}

1991

1992

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

1993

free(direntries);

1994

if (numentries == -1){

1995

perror_plus("scandir");

1790

closedir(d);

1996

1791

}

1997

1792

ret = rmdir(tempdir);

1998

1793

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

1999

perror_plus("rmdir");

1794

perror("rmdir");

2000

1795

}

2001

1796

}

2002

1797

2007

1802

&old_sigterm_action,

2008

1803

NULL));

2009

1804

if(ret == -1){

2010

perror_plus("sigaction");

1805

perror("sigaction");

2011

1806

}

2012

1807

do {

2013

1808

ret = raise(signal_received);

2014

1809

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

2015

1810

if(ret != 0){

2016

perror_plus("raise");

1811

perror("raise");

2017

1812

abort();

2018

1813

}

2019

1814

TEMP_FAILURE_RETRY(pause());