/mandos/trunk : revision 490

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

62

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

63

strtoimax() */

64

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

65

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

66

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

65

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

66

program_invocation_short_name */

67

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

67

68

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

68

69

SIOCSIFFLAGS, if_indextoname(),

69

70

if_nametoindex(), IF_NAMESIZE */

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,

127

128

static const char mandos_protocol_version[] = "1";

128

129

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

129

130

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

130

144

131

145

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

132

146

typedef struct {

137

151

gnutls_dh_params_t dh_params;

138

152

const char *priority;

139

153

gpgme_ctx_t ctx;

154

server *current_server;

140

155

} mandos_context;

141

156

142

157

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

143

158

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

144

159

.dh_bits = 1024, .priority = "SECURE256"

145

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

160

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

161

.current_server = NULL };

146

162

147

163

sig_atomic_t quit_now = 0;

148

164

int signal_received = 0;

149

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

150

173

/*

151

174

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

152

175

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

164

187

return buffer_capacity;

165

188

}

166

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

167

227

/*

168

228

* Initialize GPGME.

169

229

*/

183

243

184

244

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

185

245

if(fd == -1){

186

perror("open");

246

perror_plus("open");

187

247

return false;

188

248

}

189

249

203

263

204

264

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

205

265

if(ret == -1){

206

perror("close");

266

perror_plus("close");

207

267

}

208

268

gpgme_data_release(pgp_data);

209

269

return true;

334

394

335

395

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

336

396

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

337

perror("gpgme_data_seek");

397

perror_plus("gpgme_data_seek");

338

398

plaintext_length = -1;

339

399

goto decrypt_end;

340

400

}

345

405

(size_t)plaintext_length,

346

406

plaintext_capacity);

347

407

if(plaintext_capacity == 0){

348

perror("incbuffer");

408

perror_plus("incbuffer");

349

409

plaintext_length = -1;

350

410

goto decrypt_end;

351

411

}

358

418

break;

359

419

}

360

420

if(ret < 0){

361

perror("gpgme_data_read");

421

perror_plus("gpgme_data_read");

362

422

plaintext_length = -1;

363

423

goto decrypt_end;

364

424

}

421

481

}

422

482

423

483

/* OpenPGP credentials */

424

gnutls_certificate_allocate_credentials(&mc.cred);

484

ret = gnutls_certificate_allocate_credentials(&mc.cred);

425

485

if(ret != GNUTLS_E_SUCCESS){

426

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

427

from

428

-Wunreachable-code

429

*/

486

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

430

487

safer_gnutls_strerror(ret));

431

488

gnutls_global_deinit();

432

489

return -1;

587

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

588

645

if(tcp_sd < 0){

589

646

int e = errno;

590

perror("socket");

647

perror_plus("socket");

591

648

errno = e;

592

649

goto mandos_end;

593

650

}

607

664

}

608

665

if(ret < 0 ){

609

666

int e = errno;

610

perror("inet_pton");

667

perror_plus("inet_pton");

611

668

errno = e;

612

669

goto mandos_end;

613

670

}

649

706

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

650

707

char interface[IF_NAMESIZE];

651

708

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

652

perror("if_indextoname");

709

perror_plus("if_indextoname");

653

710

} else {

654

711

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

655

712

ip, interface, port);

669

726

sizeof(addrstr));

670

727

}

671

728

if(pcret == NULL){

672

perror("inet_ntop");

729

perror_plus("inet_ntop");

673

730

} else {

674

731

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

675

732

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

688

745

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

689

746

}

690

747

if(ret < 0){

691

int e = errno;

692

perror("connect");

693

errno = e;

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

694

753

goto mandos_end;

695

754

}

696

755

707

766

out_size - written));

708

767

if(ret == -1){

709

768

int e = errno;

710

perror("write");

769

perror_plus("write");

711

770

errno = e;

712

771

goto mandos_end;

713

772

}

738

797

goto mandos_end;

739

798

}

740

799

800

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

741

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

742

802

743

803

if(quit_now){

780

840

buffer_capacity);

781

841

if(buffer_capacity == 0){

782

842

int e = errno;

783

perror("incbuffer");

843

perror_plus("incbuffer");

784

844

errno = e;

785

845

goto mandos_end;

786

846

}

891

951

if(e == 0){

892

952

e = errno;

893

953

}

894

perror("close");

954

perror_plus("close");

895

955

}

896

956

gnutls_deinit(session);

957

errno = e;

897

958

if(quit_now){

898

e = EINTR;

959

errno = EINTR;

899

960

retval = -1;

900

961

}

901

errno = e;

902

962

}

903

963

return retval;

904

964

}

947

1007

avahi_proto_to_af(proto));

948

1008

if(ret == 0){

949

1009

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

950

1013

}

951

1014

}

952

1015

}

1006

1069

}

1007

1070

}

1008

1071

1009

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

1072

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

1010

1073

static void handle_sigterm(int sig){

1011

1074

if(quit_now){

1012

1075

return;

1014

1077

quit_now = 1;

1015

1078

signal_received = sig;

1016

1079

int old_errno = errno;

1080

/* set main loop to exit */

1017

1081

if(mc.simple_poll != NULL){

1018

1082

avahi_simple_poll_quit(mc.simple_poll);

1019

1083

}

1020

1084

errno = old_errno;

1021

1085

}

1022

1086

1087

/*

1088

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

1089

* corresponds to an acceptable network device.

1090

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

1091

*/

1092

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

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

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1188

}

1189

return 1;

1190

}

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

1023

1274

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

1024

1275

AvahiSServiceBrowser *sb = NULL;

1025

1276

int error;

1027

1278

intmax_t tmpmax;

1028

1279

char *tmp;

1029

1280

int exitcode = EXIT_SUCCESS;

1030

const char *interface = "eth0";

1281

const char *interface = "";

1031

1282

struct ifreq network;

1032

1283

int sd = -1;

1033

1284

bool take_down_interface = false;

1034

1285

uid_t uid;

1035

1286

gid_t gid;

1036

char *connect_to = NULL;

1037

1287

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

1038

1288

bool tempdir_created = false;

1039

1289

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1043

1293

bool gnutls_initialized = false;

1044

1294

bool gpgme_initialized = false;

1045

1295

float delay = 2.5f;

1296

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

1297

retrying the same server again */

1046

1298

1047

1299

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1048

1300

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1054

1306

errno = 0;

1055

1307

ret = setgid(gid);

1056

1308

if(ret == -1){

1057

perror("setgid");

1309

perror_plus("setgid");

1058

1310

}

1059

1311

1060

1312

/* Lower user privileges (temporarily) */

1061

1313

errno = 0;

1062

1314

ret = seteuid(uid);

1063

1315

if(ret == -1){

1064

perror("seteuid");

1316

perror_plus("seteuid");

1065

1317

}

1066

1318

1067

1319

if(quit_now){

1102

1354

.arg = "SECONDS",

1103

1355

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

1104

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 },

1105

1361

/*

1106

1362

* These reproduce what we would get without ARGP_NO_HELP

1107

1363

*/

1151

1407

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

1152

1408

argp_error(state, "Bad delay");

1153

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

}

1154

1417

break;

1155

1418

/*

1156

1419

* These reproduce what we would get without ARGP_NO_HELP

1184

1447

case ENOMEM:

1185

1448

default:

1186

1449

errno = ret;

1187

perror("argp_parse");

1450

perror_plus("argp_parse");

1188

1451

exitcode = EX_OSERR;

1189

1452

goto end;

1190

1453

case EINVAL:

1192

1455

goto end;

1193

1456

}

1194

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

}

1195

1514

1196

1515

if(not debug){

1197

1516

avahi_set_log_function(empty_log);

1198

1517

}

1518

1519

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

1520

struct dirent **direntries;

1521

ret = scandir(sys_class_net, &direntries, good_interface,

1522

alphasort);

1523

if(ret >= 1){

1524

/* Pick the first good interface */

1525

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

1526

if(debug){

1527

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

1528

}

1529

if(interface == NULL){

1530

perror_plus("malloc");

1531

free(direntries);

1532

exitcode = EXIT_FAILURE;

1533

goto end;

1534

}

1535

free(direntries);

1536

} else {

1537

free(direntries);

1538

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

1539

exitcode = EXIT_FAILURE;

1540

goto end;

1541

}

1542

}

1199

1543

1200

1544

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

1201

1545

from the signal handler */

1211

1555

sigemptyset(&sigterm_action.sa_mask);

1212

1556

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

1213

1557

if(ret == -1){

1214

perror("sigaddset");

1558

perror_plus("sigaddset");

1215

1559

exitcode = EX_OSERR;

1216

1560

goto end;

1217

1561

}

1218

1562

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

1219

1563

if(ret == -1){

1220

perror("sigaddset");

1564

perror_plus("sigaddset");

1221

1565

exitcode = EX_OSERR;

1222

1566

goto end;

1223

1567

}

1224

1568

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

1225

1569

if(ret == -1){

1226

perror("sigaddset");

1570

perror_plus("sigaddset");

1227

1571

exitcode = EX_OSERR;

1228

1572

goto end;

1229

1573

}

1233

1577

*/

1234

1578

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

1235

1579

if(ret == -1){

1236

perror("sigaction");

1580

perror_plus("sigaction");

1237

1581

return EX_OSERR;

1238

1582

}

1239

1583

if(old_sigterm_action.sa_handler != SIG_IGN){

1240

1584

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

1241

1585

if(ret == -1){

1242

perror("sigaction");

1586

perror_plus("sigaction");

1243

1587

exitcode = EX_OSERR;

1244

1588

goto end;

1245

1589

}

1246

1590

}

1247

1591

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

1248

1592

if(ret == -1){

1249

perror("sigaction");

1593

perror_plus("sigaction");

1250

1594

return EX_OSERR;

1251

1595

}

1252

1596

if(old_sigterm_action.sa_handler != SIG_IGN){

1253

1597

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

1254

1598

if(ret == -1){

1255

perror("sigaction");

1599

perror_plus("sigaction");

1256

1600

exitcode = EX_OSERR;

1257

1601

goto end;

1258

1602

}

1259

1603

}

1260

1604

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

1261

1605

if(ret == -1){

1262

perror("sigaction");

1606

perror_plus("sigaction");

1263

1607

return EX_OSERR;

1264

1608

}

1265

1609

if(old_sigterm_action.sa_handler != SIG_IGN){

1266

1610

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

1267

1611

if(ret == -1){

1268

perror("sigaction");

1612

perror_plus("sigaction");

1269

1613

exitcode = EX_OSERR;

1270

1614

goto end;

1271

1615

}

1272

1616

}

1273

1617

1274

1618

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

1275

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

1619

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

1276

1620

if_index = (AvahiIfIndex) if_nametoindex(interface);

1277

1621

if(if_index == 0){

1278

1622

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

1288

1632

errno = 0;

1289

1633

ret = seteuid(0);

1290

1634

if(ret == -1){

1291

perror("seteuid");

1635

perror_plus("seteuid");

1292

1636

}

1293

1637

1294

1638

#ifdef __linux__

1298

1642

bool restore_loglevel = true;

1299

1643

if(ret == -1){

1300

1644

restore_loglevel = false;

1301

perror("klogctl");

1645

perror_plus("klogctl");

1302

1646

}

1303

1647

#endif /* __linux__ */

1304

1648

1305

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1306

1650

if(sd < 0){

1307

perror("socket");

1651

perror_plus("socket");

1308

1652

exitcode = EX_OSERR;

1309

1653

#ifdef __linux__

1310

1654

if(restore_loglevel){

1311

1655

ret = klogctl(7, NULL, 0);

1312

1656

if(ret == -1){

1313

perror("klogctl");

1657

perror_plus("klogctl");

1314

1658

}

1315

1659

}

1316

1660

#endif /* __linux__ */

1318

1662

errno = 0;

1319

1663

ret = seteuid(uid);

1320

1664

if(ret == -1){

1321

perror("seteuid");

1665

perror_plus("seteuid");

1322

1666

}

1323

1667

goto end;

1324

1668

}

1325

1669

strcpy(network.ifr_name, interface);

1326

1670

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

1327

1671

if(ret == -1){

1328

perror("ioctl SIOCGIFFLAGS");

1672

perror_plus("ioctl SIOCGIFFLAGS");

1329

1673

#ifdef __linux__

1330

1674

if(restore_loglevel){

1331

1675

ret = klogctl(7, NULL, 0);

1332

1676

if(ret == -1){

1333

perror("klogctl");

1677

perror_plus("klogctl");

1334

1678

}

1335

1679

}

1336

1680

#endif /* __linux__ */

1339

1683

errno = 0;

1340

1684

ret = seteuid(uid);

1341

1685

if(ret == -1){

1342

perror("seteuid");

1686

perror_plus("seteuid");

1343

1687

}

1344

1688

goto end;

1345

1689

}

1349

1693

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

1350

1694

if(ret == -1){

1351

1695

take_down_interface = false;

1352

perror("ioctl SIOCSIFFLAGS");

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1353

1697

exitcode = EX_OSERR;

1354

1698

#ifdef __linux__

1355

1699

if(restore_loglevel){

1356

1700

ret = klogctl(7, NULL, 0);

1357

1701

if(ret == -1){

1358

perror("klogctl");

1702

perror_plus("klogctl");

1359

1703

}

1360

1704

}

1361

1705

#endif /* __linux__ */

1363

1707

errno = 0;

1364

1708

ret = seteuid(uid);

1365

1709

if(ret == -1){

1366

perror("seteuid");

1710

perror_plus("seteuid");

1367

1711

}

1368

1712

goto end;

1369

1713

}

1370

1714

}

1371

/* sleep checking until interface is running */

1715

/* Sleep checking until interface is running.

1716

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

1372

1717

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

1373

1718

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

1374

1719

if(ret == -1){

1375

perror("ioctl SIOCGIFFLAGS");

1720

perror_plus("ioctl SIOCGIFFLAGS");

1376

1721

} else if(network.ifr_flags & IFF_RUNNING){

1377

1722

break;

1378

1723

}

1379

1724

struct timespec sleeptime = { .tv_nsec = 250000000 };

1380

1725

ret = nanosleep(&sleeptime, NULL);

1381

1726

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

1382

perror("nanosleep");

1727

perror_plus("nanosleep");

1383

1728

}

1384

1729

}

1385

1730

if(not take_down_interface){

1386

1731

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

1387

1732

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

1388

1733

if(ret == -1){

1389

perror("close");

1734

perror_plus("close");

1390

1735

}

1391

1736

}

1392

1737

#ifdef __linux__

1394

1739

/* Restores kernel loglevel to default */

1395

1740

ret = klogctl(7, NULL, 0);

1396

1741

if(ret == -1){

1397

perror("klogctl");

1742

perror_plus("klogctl");

1398

1743

}

1399

1744

}

1400

1745

#endif /* __linux__ */

1404

1749

/* Lower privileges */

1405

1750

ret = seteuid(uid);

1406

1751

if(ret == -1){

1407

perror("seteuid");

1752

perror_plus("seteuid");

1408

1753

}

1409

1754

} else {

1410

1755

/* Lower privileges permanently */

1411

1756

ret = setuid(uid);

1412

1757

if(ret == -1){

1413

perror("setuid");

1758

perror_plus("setuid");

1414

1759

}

1415

1760

}

1416

1761

}

1432

1777

goto end;

1433

1778

}

1434

1779

1780

if(mkdtemp(tempdir) == NULL){

1781

perror_plus("mkdtemp");

1782

goto end;

1783

}

1435

1784

tempdir_created = true;

1436

if(mkdtemp(tempdir) == NULL){

1437

tempdir_created = false;

1438

perror("mkdtemp");

1439

goto end;

1440

}

1441

1785

1442

1786

if(quit_now){

1443

1787

goto end;

1497

1841

if(quit_now){

1498

1842

goto end;

1499

1843

}

1500

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;

1844

1845

while(not quit_now){

1846

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

1847

if(quit_now or ret == 0){

1520

1848

break;

1521

1849

}

1522

} else {

1850

sleep((int)retry_interval or 1);

1851

};

1852

1853

if (not quit_now){

1523

1854

exitcode = EXIT_SUCCESS;

1524

1855

}

1856

1525

1857

goto end;

1526

1858

}

1527

1859

1579

1911

if(debug){

1580

1912

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

1581

1913

}

1582

1583

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

}

1584

1921

1585

1922

end:

1586

1923

1607

1944

if(gpgme_initialized){

1608

1945

gpgme_release(mc.ctx);

1609

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

}

1610

1958

1611

1959

/* Take down the network interface */

1612

1960

if(take_down_interface){

1614

1962

errno = 0;

1615

1963

ret = seteuid(0);

1616

1964

if(ret == -1){

1617

perror("seteuid");

1965

perror_plus("seteuid");

1618

1966

}

1619

1967

if(geteuid() == 0){

1620

1968

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

1621

1969

if(ret == -1){

1622

perror("ioctl SIOCGIFFLAGS");

1970

perror_plus("ioctl SIOCGIFFLAGS");

1623

1971

} else if(network.ifr_flags & IFF_UP) {

1624

1972

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

1625

1973

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

1626

1974

if(ret == -1){

1627

perror("ioctl SIOCSIFFLAGS");

1975

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1628

1976

}

1629

1977

}

1630

1978

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

1631

1979

if(ret == -1){

1632

perror("close");

1980

perror_plus("close");

1633

1981

}

1634

1982

/* Lower privileges permanently */

1635

1983

errno = 0;

1636

1984

ret = setuid(uid);

1637

1985

if(ret == -1){

1638

perror("setuid");

1986

perror_plus("setuid");

1639

1987

}

1640

1988

}

1641

1989

}

1642

1990

1643

/* Removes the temp directory used by GPGME */

1991

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

1644

1992

if(tempdir_created){

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

}

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];

1665

1999

char *fullname = NULL;

1666

2000

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

1667

2001

direntry->d_name);

1668

2002

if(ret < 0){

1669

perror("asprintf");

2003

perror_plus("asprintf");

1670

2004

continue;

1671

2005

}

1672

2006

ret = remove(fullname);

1676

2010

}

1677

2011

free(fullname);

1678

2012

}

1679

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");

1680

2020

}

1681

2021

ret = rmdir(tempdir);

1682

2022

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

1683

perror("rmdir");

2023

perror_plus("rmdir");

1684

2024

}

1685

2025

}

1686

2026

1691

2031

&old_sigterm_action,

1692

2032

NULL));

1693

2033

if(ret == -1){

1694

perror("sigaction");

2034

perror_plus("sigaction");

1695

2035

}

1696

2036

do {

1697

2037

ret = raise(signal_received);

1698

2038

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

1699

2039

if(ret != 0){

1700

perror("raise");

2040

perror_plus("raise");

1701

2041

abort();

1702

2042

}

1703

2043

TEMP_FAILURE_RETRY(pause());