/mandos/release : revision 24.1.154

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 */

67

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

65

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

66

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

68

67

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

69

68

SIOCSIFFLAGS, if_indextoname(),

70

69

if_nametoindex(), IF_NAMESIZE */

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>";

131

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

132

char *connect_to = NULL;

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;

129

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

144

130

145

131

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

146

132

typedef struct {

151

137

gnutls_dh_params_t dh_params;

152

138

const char *priority;

153

139

gpgme_ctx_t ctx;

154

server *current_server;

155

140

} mandos_context;

156

141

157

142

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

158

143

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

159

144

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

145

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

162

146

163

147

sig_atomic_t quit_now = 0;

164

148

int signal_received = 0;

165

149

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

150

/*

174

151

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

175

152

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

187

164

return buffer_capacity;

188

165

}

189

166

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

167

/*

229

168

* Initialize GPGME.

230

169

*/

244

183

245

184

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

246

185

if(fd == -1){

247

perror_plus("open");

186

perror("open");

248

187

return false;

249

188

}

250

189

264

203

265

204

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

266

205

if(ret == -1){

267

perror_plus("close");

206

perror("close");

268

207

}

269

208

gpgme_data_release(pgp_data);

270

209

return true;

283

222

return false;

284

223

}

285

224

286

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

225

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

287

226

rc = gpgme_get_engine_info(&engine_info);

288

227

if(rc != GPG_ERR_NO_ERROR){

289

228

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

395

334

396

335

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

397

336

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

398

perror_plus("gpgme_data_seek");

337

perror("gpgme_data_seek");

399

338

plaintext_length = -1;

400

339

goto decrypt_end;

401

340

}

406

345

(size_t)plaintext_length,

407

346

plaintext_capacity);

408

347

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

348

perror("incbuffer");

410

349

plaintext_length = -1;

411

350

goto decrypt_end;

412

351

}

419

358

break;

420

359

}

421

360

if(ret < 0){

422

perror_plus("gpgme_data_read");

361

perror("gpgme_data_read");

423

362

plaintext_length = -1;

424

363

goto decrypt_end;

425

364

}

482

421

}

483

422

484

423

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

424

gnutls_certificate_allocate_credentials(&mc.cred);

486

425

if(ret != GNUTLS_E_SUCCESS){

487

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

426

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

427

from

428

-Wunreachable-code

429

*/

488

430

safer_gnutls_strerror(ret));

489

431

gnutls_global_deinit();

490

432

return -1;

645

587

tcp_sd = socket(pf, SOCK_STREAM, 0);

646

588

if(tcp_sd < 0){

647

589

int e = errno;

648

perror_plus("socket");

590

perror("socket");

649

591

errno = e;

650

592

goto mandos_end;

651

593

}

665

607

}

666

608

if(ret < 0 ){

667

609

int e = errno;

668

perror_plus("inet_pton");

610

perror("inet_pton");

669

611

errno = e;

670

612

goto mandos_end;

671

613

}

707

649

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

708

650

char interface[IF_NAMESIZE];

709

651

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

710

perror_plus("if_indextoname");

652

perror("if_indextoname");

711

653

} else {

712

654

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

713

655

ip, interface, port);

727

669

sizeof(addrstr));

728

670

}

729

671

if(pcret == NULL){

730

perror_plus("inet_ntop");

672

perror("inet_ntop");

731

673

} else {

732

674

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

733

675

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

746

688

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

747

689

}

748

690

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

691

int e = errno;

692

perror("connect");

693

errno = e;

754

694

goto mandos_end;

755

695

}

756

696

767

707

out_size - written));

768

708

if(ret == -1){

769

709

int e = errno;

770

perror_plus("write");

710

perror("write");

771

711

errno = e;

772

712

goto mandos_end;

773

713

}

798

738

goto mandos_end;

799

739

}

800

740

801

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

802

741

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

803

742

804

743

if(quit_now){

841

780

buffer_capacity);

842

781

if(buffer_capacity == 0){

843

782

int e = errno;

844

perror_plus("incbuffer");

783

perror("incbuffer");

845

784

errno = e;

846

785

goto mandos_end;

847

786

}

952

891

if(e == 0){

953

892

e = errno;

954

893

}

955

perror_plus("close");

894

perror("close");

956

895

}

957

896

gnutls_deinit(session);

958

errno = e;

959

897

if(quit_now){

960

errno = EINTR;

898

e = EINTR;

961

899

retval = -1;

962

900

}

901

errno = e;

963

902

}

964

903

return retval;

965

904

}

1008

947

avahi_proto_to_af(proto));

1009

948

if(ret == 0){

1010

949

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1014

950

}

1015

951

}

1016

952

}

1070

1006

}

1071

1007

}

1072

1008

1073

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

1009

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

1074

1010

static void handle_sigterm(int sig){

1075

1011

if(quit_now){

1076

1012

return;

1078

1014

quit_now = 1;

1079

1015

signal_received = sig;

1080

1016

int old_errno = errno;

1081

/* set main loop to exit */

1082

1017

if(mc.simple_poll != NULL){

1083

1018

avahi_simple_poll_quit(mc.simple_poll);

1084

1019

}

1085

1020

errno = old_errno;

1086

1021

}

1087

1022

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

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

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

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

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1153

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1155

if(debug){

1156

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

1157

if_entry->d_name);

1158

}

1159

return 0;

1160

}

1161

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

1162

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

1163

if(debug){

1164

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

1165

if_entry->d_name);

1166

}

1167

return 1;

1168

}

1169

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

1170

if(not (flags & IFF_BROADCAST)){

1171

if(debug){

1172

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

1173

if_entry->d_name);

1174

}

1175

return 0;

1176

}

1177

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

1178

if(flags & IFF_NOARP){

1179

if(debug){

1180

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

1181

if_entry->d_name);

1182

}

1183

return 0;

1184

}

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

if_entry->d_name);

1189

}

1190

return 1;

1191

}

1192

1193

int notdotentries(const struct dirent *direntry){

1194

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

1195

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

1196

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

1197

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

1198

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

1199

return 0;

1200

}

1201

return 1;

1202

}

1203

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1205

int ret;

1206

struct timespec now;

1207

struct timespec waited_time;

1208

intmax_t block_time;

1209

1210

while(true){

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

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

1215

}

1216

ret = avahi_simple_poll_iterate(s, -1);

1217

} else {

1218

if (debug){

1219

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

1220

" or wait\n");

1221

}

1222

/* the current time */

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1224

if(ret == -1){

1225

perror_plus("clock_gettime");

1226

return -1;

1227

}

1228

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

1229

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

1230

waited_time.tv_sec = (now.tv_sec

1231

- mc.current_server->last_seen.tv_sec);

1232

waited_time.tv_nsec = (now.tv_nsec

1233

- mc.current_server->last_seen.tv_nsec);

1234

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

1235

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

1236

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

1237

block_time = ((retry_interval

1238

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

1239

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

1240

1241

if (debug){

1242

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

1243

}

1244

1245

if(block_time <= 0){

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1250

if(ret == 0){

1251

avahi_simple_poll_quit(mc.simple_poll);

1252

return 0;

1253

}

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1255

&mc.current_server->last_seen);

1256

if(ret == -1){

1257

perror_plus("clock_gettime");

1258

return -1;

1259

}

1260

mc.current_server = mc.current_server->next;

1261

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

1262

servers, but don't block */

1263

}

1264

1265

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

1266

}

1267

if(ret != 0){

1268

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

1269

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

1270

}

1271

}

1272

}

1273

}

1274

1275

1023

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

1276

1024

AvahiSServiceBrowser *sb = NULL;

1277

1025

int error;

1279

1027

intmax_t tmpmax;

1280

1028

char *tmp;

1281

1029

int exitcode = EXIT_SUCCESS;

1282

const char *interface = "";

1030

const char *interface = "eth0";

1283

1031

struct ifreq network;

1284

1032

int sd = -1;

1285

1033

bool take_down_interface = false;

1286

1034

uid_t uid;

1287

1035

gid_t gid;

1036

char *connect_to = NULL;

1288

1037

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

1289

1038

bool tempdir_created = false;

1290

1039

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1294

1043

bool gnutls_initialized = false;

1295

1044

bool gpgme_initialized = false;

1296

1045

float delay = 2.5f;

1297

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

1298

retrying the same server again */

1299

1046

1300

1047

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1301

1048

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1307

1054

errno = 0;

1308

1055

ret = setgid(gid);

1309

1056

if(ret == -1){

1310

perror_plus("setgid");

1057

perror("setgid");

1311

1058

}

1312

1059

1313

1060

/* Lower user privileges (temporarily) */

1314

1061

errno = 0;

1315

1062

ret = seteuid(uid);

1316

1063

if(ret == -1){

1317

perror_plus("seteuid");

1064

perror("seteuid");

1318

1065

}

1319

1066

1320

1067

if(quit_now){

1355

1102

.arg = "SECONDS",

1356

1103

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

1357

1104

.group = 2 },

1358

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

1359

.arg = "SECONDS",

1360

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

1361

.group = 2 },

1362

1105

/*

1363

1106

* These reproduce what we would get without ARGP_NO_HELP

1364

1107

*/

1408

1151

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

1409

1152

argp_error(state, "Bad delay");

1410

1153

}

1411

case 132: /* --retry */

1412

errno = 0;

1413

retry_interval = strtod(arg, &tmp);

1414

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

1415

or (retry_interval * 1000) > INT_MAX

1416

or retry_interval < 0){

1417

argp_error(state, "Bad retry interval");

1418

}

1419

1154

break;

1420

1155

/*

1421

1156

* These reproduce what we would get without ARGP_NO_HELP

1449

1184

case ENOMEM:

1450

1185

default:

1451

1186

errno = ret;

1452

perror_plus("argp_parse");

1187

perror("argp_parse");

1453

1188

exitcode = EX_OSERR;

1454

1189

goto end;

1455

1190

case EINVAL:

1457

1192

goto end;

1458

1193

}

1459

1194

}

1460

1461

{

1462

/* Work around Debian bug #633582:

1463

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

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

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

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

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

1519

}

1520

1195

1521

1196

if(not debug){

1522

1197

avahi_set_log_function(empty_log);

1523

1198

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

1549

1199

1550

1200

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

1551

1201

from the signal handler */

1561

1211

sigemptyset(&sigterm_action.sa_mask);

1562

1212

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

1563

1213

if(ret == -1){

1564

perror_plus("sigaddset");

1214

perror("sigaddset");

1565

1215

exitcode = EX_OSERR;

1566

1216

goto end;

1567

1217

}

1568

1218

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

1569

1219

if(ret == -1){

1570

perror_plus("sigaddset");

1220

perror("sigaddset");

1571

1221

exitcode = EX_OSERR;

1572

1222

goto end;

1573

1223

}

1574

1224

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

1575

1225

if(ret == -1){

1576

perror_plus("sigaddset");

1226

perror("sigaddset");

1577

1227

exitcode = EX_OSERR;

1578

1228

goto end;

1579

1229

}

1583

1233

*/

1584

1234

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

1585

1235

if(ret == -1){

1586

perror_plus("sigaction");

1236

perror("sigaction");

1587

1237

return EX_OSERR;

1588

1238

}

1589

1239

if(old_sigterm_action.sa_handler != SIG_IGN){

1590

1240

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

1591

1241

if(ret == -1){

1592

perror_plus("sigaction");

1242

perror("sigaction");

1593

1243

exitcode = EX_OSERR;

1594

1244

goto end;

1595

1245

}

1596

1246

}

1597

1247

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

1598

1248

if(ret == -1){

1599

perror_plus("sigaction");

1249

perror("sigaction");

1600

1250

return EX_OSERR;

1601

1251

}

1602

1252

if(old_sigterm_action.sa_handler != SIG_IGN){

1603

1253

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

1604

1254

if(ret == -1){

1605

perror_plus("sigaction");

1255

perror("sigaction");

1606

1256

exitcode = EX_OSERR;

1607

1257

goto end;

1608

1258

}

1609

1259

}

1610

1260

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

1611

1261

if(ret == -1){

1612

perror_plus("sigaction");

1262

perror("sigaction");

1613

1263

return EX_OSERR;

1614

1264

}

1615

1265

if(old_sigterm_action.sa_handler != SIG_IGN){

1616

1266

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

1617

1267

if(ret == -1){

1618

perror_plus("sigaction");

1268

perror("sigaction");

1619

1269

exitcode = EX_OSERR;

1620

1270

goto end;

1621

1271

}

1622

1272

}

1623

1273

1624

1274

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

1625

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

1275

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

1626

1276

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

1277

if(if_index == 0){

1628

1278

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

1638

1288

errno = 0;

1639

1289

ret = seteuid(0);

1640

1290

if(ret == -1){

1641

perror_plus("seteuid");

1291

perror("seteuid");

1642

1292

}

1643

1293

1644

1294

#ifdef __linux__

1648

1298

bool restore_loglevel = true;

1649

1299

if(ret == -1){

1650

1300

restore_loglevel = false;

1651

perror_plus("klogctl");

1301

perror("klogctl");

1652

1302

}

1653

1303

#endif /* __linux__ */

1654

1304

1655

1305

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

1306

if(sd < 0){

1657

perror_plus("socket");

1307

perror("socket");

1658

1308

exitcode = EX_OSERR;

1659

1309

#ifdef __linux__

1660

1310

if(restore_loglevel){

1661

1311

ret = klogctl(7, NULL, 0);

1662

1312

if(ret == -1){

1663

perror_plus("klogctl");

1313

perror("klogctl");

1664

1314

}

1665

1315

}

1666

1316

#endif /* __linux__ */

1668

1318

errno = 0;

1669

1319

ret = seteuid(uid);

1670

1320

if(ret == -1){

1671

perror_plus("seteuid");

1321

perror("seteuid");

1672

1322

}

1673

1323

goto end;

1674

1324

}

1675

1325

strcpy(network.ifr_name, interface);

1676

1326

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

1677

1327

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1328

perror("ioctl SIOCGIFFLAGS");

1679

1329

#ifdef __linux__

1680

1330

if(restore_loglevel){

1681

1331

ret = klogctl(7, NULL, 0);

1682

1332

if(ret == -1){

1683

perror_plus("klogctl");

1333

perror("klogctl");

1684

1334

}

1685

1335

}

1686

1336

#endif /* __linux__ */

1689

1339

errno = 0;

1690

1340

ret = seteuid(uid);

1691

1341

if(ret == -1){

1692

perror_plus("seteuid");

1342

perror("seteuid");

1693

1343

}

1694

1344

goto end;

1695

1345

}

1699

1349

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

1700

1350

if(ret == -1){

1701

1351

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1352

perror("ioctl SIOCSIFFLAGS");

1703

1353

exitcode = EX_OSERR;

1704

1354

#ifdef __linux__

1705

1355

if(restore_loglevel){

1706

1356

ret = klogctl(7, NULL, 0);

1707

1357

if(ret == -1){

1708

perror_plus("klogctl");

1358

perror("klogctl");

1709

1359

}

1710

1360

}

1711

1361

#endif /* __linux__ */

1713

1363

errno = 0;

1714

1364

ret = seteuid(uid);

1715

1365

if(ret == -1){

1716

perror_plus("seteuid");

1366

perror("seteuid");

1717

1367

}

1718

1368

goto end;

1719

1369

}

1720

1370

}

1721

/* Sleep checking until interface is running.

1722

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

1371

/* sleep checking until interface is running */

1723

1372

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

1724

1373

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

1725

1374

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1375

perror("ioctl SIOCGIFFLAGS");

1727

1376

} else if(network.ifr_flags & IFF_RUNNING){

1728

1377

break;

1729

1378

}

1730

1379

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

1380

ret = nanosleep(&sleeptime, NULL);

1732

1381

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

1733

perror_plus("nanosleep");

1382

perror("nanosleep");

1734

1383

}

1735

1384

}

1736

1385

if(not take_down_interface){

1737

1386

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

1738

1387

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

1739

1388

if(ret == -1){

1740

perror_plus("close");

1389

perror("close");

1741

1390

}

1742

1391

}

1743

1392

#ifdef __linux__

1745

1394

/* Restores kernel loglevel to default */

1746

1395

ret = klogctl(7, NULL, 0);

1747

1396

if(ret == -1){

1748

perror_plus("klogctl");

1397

perror("klogctl");

1749

1398

}

1750

1399

}

1751

1400

#endif /* __linux__ */

1755

1404

/* Lower privileges */

1756

1405

ret = seteuid(uid);

1757

1406

if(ret == -1){

1758

perror_plus("seteuid");

1407

perror("seteuid");

1759

1408

}

1760

1409

} else {

1761

1410

/* Lower privileges permanently */

1762

1411

ret = setuid(uid);

1763

1412

if(ret == -1){

1764

perror_plus("setuid");

1413

perror("setuid");

1765

1414

}

1766

1415

}

1767

1416

}

1783

1432

goto end;

1784

1433

}

1785

1434

1435

tempdir_created = true;

1786

1436

if(mkdtemp(tempdir) == NULL){

1787

perror_plus("mkdtemp");

1437

tempdir_created = false;

1438

perror("mkdtemp");

1788

1439

goto end;

1789

1440

}

1790

tempdir_created = true;

1791

1441

1792

1442

if(quit_now){

1793

1443

goto end;

1835

1485

1836

1486

port = (uint16_t)tmpmax;

1837

1487

*address = '\0';

1488

address = connect_to;

1838

1489

/* Colon in address indicates IPv6 */

1839

1490

int af;

1840

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

1491

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

1841

1492

af = AF_INET6;

1842

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

1843

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

1844

{

1845

connect_to++;

1846

address[-1] = '\0';

1847

}

1848

1493

} else {

1849

1494

af = AF_INET;

1850

1495

}

1851

address = connect_to;

1852

1496

1853

1497

if(quit_now){

1854

1498

goto end;

1855

1499

}

1856

1500

1857

while(not quit_now){

1858

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

1859

if(quit_now or ret == 0){

1860

break;

1861

}

1862

if(debug){

1863

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

1864

(int)retry_interval);

1865

}

1866

sleep((int)retry_interval);

1867

}

1868

1869

if (not quit_now){

1501

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

1502

if(ret < 0){

1503

switch(errno){

1504

case ENETUNREACH:

1505

case EHOSTDOWN:

1506

case EHOSTUNREACH:

1507

exitcode = EX_NOHOST;

1508

break;

1509

case EINVAL:

1510

exitcode = EX_USAGE;

1511

break;

1512

case EIO:

1513

exitcode = EX_IOERR;

1514

break;

1515

case EPROTO:

1516

exitcode = EX_PROTOCOL;

1517

break;

1518

default:

1519

exitcode = EX_OSERR;

1520

break;

1521

}

1522

} else {

1870

1523

exitcode = EXIT_SUCCESS;

1871

1524

}

1872

1873

1525

goto end;

1874

1526

}

1875

1527

1927

1579

if(debug){

1928

1580

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

1929

1581

}

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

1933

if(debug){

1934

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

1935

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

1936

}

1582

1583

avahi_simple_poll_loop(mc.simple_poll);

1937

1584

1938

1585

end:

1939

1586

1960

1607

if(gpgme_initialized){

1961

1608

gpgme_release(mc.ctx);

1962

1609

}

1963

1964

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

1965

has seen */

1966

if(mc.current_server != NULL){

1967

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

1968

while(mc.current_server != NULL){

1969

server *next = mc.current_server->next;

1970

free(mc.current_server);

1971

mc.current_server = next;

1972

}

1973

}

1974

1610

1975

1611

/* Take down the network interface */

1976

1612

if(take_down_interface){

1978

1614

errno = 0;

1979

1615

ret = seteuid(0);

1980

1616

if(ret == -1){

1981

perror_plus("seteuid");

1617

perror("seteuid");

1982

1618

}

1983

1619

if(geteuid() == 0){

1984

1620

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

1985

1621

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1622

perror("ioctl SIOCGIFFLAGS");

1987

1623

} else if(network.ifr_flags & IFF_UP) {

1988

1624

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

1989

1625

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

1990

1626

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1627

perror("ioctl SIOCSIFFLAGS");

1992

1628

}

1993

1629

}

1994

1630

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

1995

1631

if(ret == -1){

1996

perror_plus("close");

1632

perror("close");

1997

1633

}

1998

1634

/* Lower privileges permanently */

1999

1635

errno = 0;

2000

1636

ret = setuid(uid);

2001

1637

if(ret == -1){

2002

perror_plus("setuid");

1638

perror("setuid");

2003

1639

}

2004

1640

}

2005

1641

}

2006

1642

2007

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

1643

/* Removes the temp directory used by GPGME */

2008

1644

if(tempdir_created){

2009

struct dirent **direntries = NULL;

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

direntry = direntries[i];

1645

DIR *d;

1646

struct dirent *direntry;

1647

d = opendir(tempdir);

1648

if(d == NULL){

1649

if(errno != ENOENT){

1650

perror("opendir");

1651

}

1652

} else {

1653

while(true){

1654

direntry = readdir(d);

1655

if(direntry == NULL){

1656

break;

1657

}

1658

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

1659

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

1660

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

1661

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

1662

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

1663

continue;

1664

}

2016

1665

char *fullname = NULL;

2017

1666

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

2018

1667

direntry->d_name);

2019

1668

if(ret < 0){

2020

perror_plus("asprintf");

1669

perror("asprintf");

2021

1670

continue;

2022

1671

}

2023

1672

ret = remove(fullname);

2027

1676

}

2028

1677

free(fullname);

2029

1678

}

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

1679

closedir(d);

2036

1680

}

2037

1681

ret = rmdir(tempdir);

2038

1682

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

2039

perror_plus("rmdir");

1683

perror("rmdir");

2040

1684

}

2041

1685

}

2042

1686

2047

1691

&old_sigterm_action,

2048

1692

NULL));

2049

1693

if(ret == -1){

2050

perror_plus("sigaction");

1694

perror("sigaction");

2051

1695

}

2052

1696

do {

2053

1697

ret = raise(signal_received);

2054

1698

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

2055

1699

if(ret != 0){

2056

perror_plus("raise");

1700

perror("raise");

2057

1701

abort();

2058

1702

}

2059

1703

TEMP_FAILURE_RETRY(pause());