/mandos/trunk : revision 24.1.186

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

/* 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

167

228

/*

168

229

* Initialize GPGME.

169

230

*/

183

244

184

245

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

185

246

if(fd == -1){

186

perror("open");

247

perror_plus("open");

187

248

return false;

188

249

}

189

250

203

264

204

265

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

205

266

if(ret == -1){

206

perror("close");

267

perror_plus("close");

207

268

}

208

269

gpgme_data_release(pgp_data);

209

270

return true;

222

283

return false;

223

284

}

224

285

225

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

286

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

226

287

rc = gpgme_get_engine_info(&engine_info);

227

288

if(rc != GPG_ERR_NO_ERROR){

228

289

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

334

395

335

396

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

336

397

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

337

perror("gpgme_data_seek");

398

perror_plus("gpgme_data_seek");

338

399

plaintext_length = -1;

339

400

goto decrypt_end;

340

401

}

345

406

(size_t)plaintext_length,

346

407

plaintext_capacity);

347

408

if(plaintext_capacity == 0){

348

perror("incbuffer");

409

perror_plus("incbuffer");

349

410

plaintext_length = -1;

350

411

goto decrypt_end;

351

412

}

358

419

break;

359

420

}

360

421

if(ret < 0){

361

perror("gpgme_data_read");

422

perror_plus("gpgme_data_read");

362

423

plaintext_length = -1;

363

424

goto decrypt_end;

364

425

}

421

482

}

422

483

423

484

/* OpenPGP credentials */

424

gnutls_certificate_allocate_credentials(&mc.cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

425

486

if(ret != GNUTLS_E_SUCCESS){

426

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

427

from

428

-Wunreachable-code

429

*/

487

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

430

488

safer_gnutls_strerror(ret));

431

489

gnutls_global_deinit();

432

490

return -1;

587

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

588

646

if(tcp_sd < 0){

589

647

int e = errno;

590

perror("socket");

648

perror_plus("socket");

591

649

errno = e;

592

650

goto mandos_end;

593

651

}

607

665

}

608

666

if(ret < 0 ){

609

667

int e = errno;

610

perror("inet_pton");

668

perror_plus("inet_pton");

611

669

errno = e;

612

670

goto mandos_end;

613

671

}

649

707

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

650

708

char interface[IF_NAMESIZE];

651

709

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

652

perror("if_indextoname");

710

perror_plus("if_indextoname");

653

711

} else {

654

712

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

655

713

ip, interface, port);

669

727

sizeof(addrstr));

670

728

}

671

729

if(pcret == NULL){

672

perror("inet_ntop");

730

perror_plus("inet_ntop");

673

731

} else {

674

732

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

675

733

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

688

746

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

689

747

}

690

748

if(ret < 0){

691

int e = errno;

692

perror("connect");

693

errno = e;

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

694

754

goto mandos_end;

695

755

}

696

756

707

767

out_size - written));

708

768

if(ret == -1){

709

769

int e = errno;

710

perror("write");

770

perror_plus("write");

711

771

errno = e;

712

772

goto mandos_end;

713

773

}

738

798

goto mandos_end;

739

799

}

740

800

801

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

741

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

742

803

743

804

if(quit_now){

780

841

buffer_capacity);

781

842

if(buffer_capacity == 0){

782

843

int e = errno;

783

perror("incbuffer");

844

perror_plus("incbuffer");

784

845

errno = e;

785

846

goto mandos_end;

786

847

}

891

952

if(e == 0){

892

953

e = errno;

893

954

}

894

perror("close");

955

perror_plus("close");

895

956

}

896

957

gnutls_deinit(session);

958

errno = e;

897

959

if(quit_now){

898

e = EINTR;

960

errno = EINTR;

899

961

retval = -1;

900

962

}

901

errno = e;

902

963

}

903

964

return retval;

904

965

}

947

1008

avahi_proto_to_af(proto));

948

1009

if(ret == 0){

949

1010

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

950

1014

}

951

1015

}

952

1016

}

1006

1070

}

1007

1071

}

1008

1072

1009

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

1073

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

1010

1074

static void handle_sigterm(int sig){

1011

1075

if(quit_now){

1012

1076

return;

1014

1078

quit_now = 1;

1015

1079

signal_received = sig;

1016

1080

int old_errno = errno;

1081

/* set main loop to exit */

1017

1082

if(mc.simple_poll != NULL){

1018

1083

avahi_simple_poll_quit(mc.simple_poll);

1019

1084

}

1020

1085

errno = old_errno;

1021

1086

}

1022

1087

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

1023

1275

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

1024

1276

AvahiSServiceBrowser *sb = NULL;

1025

1277

int error;

1027

1279

intmax_t tmpmax;

1028

1280

char *tmp;

1029

1281

int exitcode = EXIT_SUCCESS;

1030

const char *interface = "eth0";

1282

const char *interface = "";

1031

1283

struct ifreq network;

1032

1284

int sd = -1;

1033

1285

bool take_down_interface = false;

1034

1286

uid_t uid;

1035

1287

gid_t gid;

1036

char *connect_to = NULL;

1037

1288

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

1038

1289

bool tempdir_created = false;

1039

1290

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1043

1294

bool gnutls_initialized = false;

1044

1295

bool gpgme_initialized = false;

1045

1296

float delay = 2.5f;

1297

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

1298

retrying the same server again */

1046

1299

1047

1300

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1048

1301

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1054

1307

errno = 0;

1055

1308

ret = setgid(gid);

1056

1309

if(ret == -1){

1057

perror("setgid");

1310

perror_plus("setgid");

1058

1311

}

1059

1312

1060

1313

/* Lower user privileges (temporarily) */

1061

1314

errno = 0;

1062

1315

ret = seteuid(uid);

1063

1316

if(ret == -1){

1064

perror("seteuid");

1317

perror_plus("seteuid");

1065

1318

}

1066

1319

1067

1320

if(quit_now){

1102

1355

.arg = "SECONDS",

1103

1356

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

1104

1357

.group = 2 },

1358

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

1359

.arg = "SECONDS",

1360

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

1361

.group = 2 },

1105

1362

/*

1106

1363

* These reproduce what we would get without ARGP_NO_HELP

1107

1364

*/

1151

1408

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

1152

1409

argp_error(state, "Bad delay");

1153

1410

}

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

}

1154

1419

break;

1155

1420

/*

1156

1421

* These reproduce what we would get without ARGP_NO_HELP

1184

1449

case ENOMEM:

1185

1450

default:

1186

1451

errno = ret;

1187

perror("argp_parse");

1452

perror_plus("argp_parse");

1188

1453

exitcode = EX_OSERR;

1189

1454

goto end;

1190

1455

case EINVAL:

1192

1457

goto end;

1193

1458

}

1194

1459

}

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

}

1195

1520

1196

1521

if(not debug){

1197

1522

avahi_set_log_function(empty_log);

1198

1523

}

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

}

1199

1549

1200

1550

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

1201

1551

from the signal handler */

1211

1561

sigemptyset(&sigterm_action.sa_mask);

1212

1562

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

1213

1563

if(ret == -1){

1214

perror("sigaddset");

1564

perror_plus("sigaddset");

1215

1565

exitcode = EX_OSERR;

1216

1566

goto end;

1217

1567

}

1218

1568

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

1219

1569

if(ret == -1){

1220

perror("sigaddset");

1570

perror_plus("sigaddset");

1221

1571

exitcode = EX_OSERR;

1222

1572

goto end;

1223

1573

}

1224

1574

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

1225

1575

if(ret == -1){

1226

perror("sigaddset");

1576

perror_plus("sigaddset");

1227

1577

exitcode = EX_OSERR;

1228

1578

goto end;

1229

1579

}

1233

1583

*/

1234

1584

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

1235

1585

if(ret == -1){

1236

perror("sigaction");

1586

perror_plus("sigaction");

1237

1587

return EX_OSERR;

1238

1588

}

1239

1589

if(old_sigterm_action.sa_handler != SIG_IGN){

1240

1590

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

1241

1591

if(ret == -1){

1242

perror("sigaction");

1592

perror_plus("sigaction");

1243

1593

exitcode = EX_OSERR;

1244

1594

goto end;

1245

1595

}

1246

1596

}

1247

1597

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

1248

1598

if(ret == -1){

1249

perror("sigaction");

1599

perror_plus("sigaction");

1250

1600

return EX_OSERR;

1251

1601

}

1252

1602

if(old_sigterm_action.sa_handler != SIG_IGN){

1253

1603

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

1254

1604

if(ret == -1){

1255

perror("sigaction");

1605

perror_plus("sigaction");

1256

1606

exitcode = EX_OSERR;

1257

1607

goto end;

1258

1608

}

1259

1609

}

1260

1610

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

1261

1611

if(ret == -1){

1262

perror("sigaction");

1612

perror_plus("sigaction");

1263

1613

return EX_OSERR;

1264

1614

}

1265

1615

if(old_sigterm_action.sa_handler != SIG_IGN){

1266

1616

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

1267

1617

if(ret == -1){

1268

perror("sigaction");

1618

perror_plus("sigaction");

1269

1619

exitcode = EX_OSERR;

1270

1620

goto end;

1271

1621

}

1272

1622

}

1273

1623

1274

1624

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

1275

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

1625

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

1276

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1277

1627

if(if_index == 0){

1278

1628

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

1288

1638

errno = 0;

1289

1639

ret = seteuid(0);

1290

1640

if(ret == -1){

1291

perror("seteuid");

1641

perror_plus("seteuid");

1292

1642

}

1293

1643

1294

1644

#ifdef __linux__

1298

1648

bool restore_loglevel = true;

1299

1649

if(ret == -1){

1300

1650

restore_loglevel = false;

1301

perror("klogctl");

1651

perror_plus("klogctl");

1302

1652

}

1303

1653

#endif /* __linux__ */

1304

1654

1305

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1306

1656

if(sd < 0){

1307

perror("socket");

1657

perror_plus("socket");

1308

1658

exitcode = EX_OSERR;

1309

1659

#ifdef __linux__

1310

1660

if(restore_loglevel){

1311

1661

ret = klogctl(7, NULL, 0);

1312

1662

if(ret == -1){

1313

perror("klogctl");

1663

perror_plus("klogctl");

1314

1664

}

1315

1665

}

1316

1666

#endif /* __linux__ */

1318

1668

errno = 0;

1319

1669

ret = seteuid(uid);

1320

1670

if(ret == -1){

1321

perror("seteuid");

1671

perror_plus("seteuid");

1322

1672

}

1323

1673

goto end;

1324

1674

}

1325

1675

strcpy(network.ifr_name, interface);

1326

1676

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

1327

1677

if(ret == -1){

1328

perror("ioctl SIOCGIFFLAGS");

1678

perror_plus("ioctl SIOCGIFFLAGS");

1329

1679

#ifdef __linux__

1330

1680

if(restore_loglevel){

1331

1681

ret = klogctl(7, NULL, 0);

1332

1682

if(ret == -1){

1333

perror("klogctl");

1683

perror_plus("klogctl");

1334

1684

}

1335

1685

}

1336

1686

#endif /* __linux__ */

1339

1689

errno = 0;

1340

1690

ret = seteuid(uid);

1341

1691

if(ret == -1){

1342

perror("seteuid");

1692

perror_plus("seteuid");

1343

1693

}

1344

1694

goto end;

1345

1695

}

1349

1699

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

1350

1700

if(ret == -1){

1351

1701

take_down_interface = false;

1352

perror("ioctl SIOCSIFFLAGS");

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1353

1703

exitcode = EX_OSERR;

1354

1704

#ifdef __linux__

1355

1705

if(restore_loglevel){

1356

1706

ret = klogctl(7, NULL, 0);

1357

1707

if(ret == -1){

1358

perror("klogctl");

1708

perror_plus("klogctl");

1359

1709

}

1360

1710

}

1361

1711

#endif /* __linux__ */

1363

1713

errno = 0;

1364

1714

ret = seteuid(uid);

1365

1715

if(ret == -1){

1366

perror("seteuid");

1716

perror_plus("seteuid");

1367

1717

}

1368

1718

goto end;

1369

1719

}

1370

1720

}

1371

/* sleep checking until interface is running */

1721

/* Sleep checking until interface is running.

1722

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

1372

1723

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

1373

1724

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

1374

1725

if(ret == -1){

1375

perror("ioctl SIOCGIFFLAGS");

1726

perror_plus("ioctl SIOCGIFFLAGS");

1376

1727

} else if(network.ifr_flags & IFF_RUNNING){

1377

1728

break;

1378

1729

}

1379

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1380

1731

ret = nanosleep(&sleeptime, NULL);

1381

1732

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

1382

perror("nanosleep");

1733

perror_plus("nanosleep");

1383

1734

}

1384

1735

}

1385

1736

if(not take_down_interface){

1386

1737

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

1387

1738

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

1388

1739

if(ret == -1){

1389

perror("close");

1740

perror_plus("close");

1390

1741

}

1391

1742

}

1392

1743

#ifdef __linux__

1394

1745

/* Restores kernel loglevel to default */

1395

1746

ret = klogctl(7, NULL, 0);

1396

1747

if(ret == -1){

1397

perror("klogctl");

1748

perror_plus("klogctl");

1398

1749

}

1399

1750

}

1400

1751

#endif /* __linux__ */

1404

1755

/* Lower privileges */

1405

1756

ret = seteuid(uid);

1406

1757

if(ret == -1){

1407

perror("seteuid");

1758

perror_plus("seteuid");

1408

1759

}

1409

1760

} else {

1410

1761

/* Lower privileges permanently */

1411

1762

ret = setuid(uid);

1412

1763

if(ret == -1){

1413

perror("setuid");

1764

perror_plus("setuid");

1414

1765

}

1415

1766

}

1416

1767

}

1432

1783

goto end;

1433

1784

}

1434

1785

1786

if(mkdtemp(tempdir) == NULL){

1787

perror_plus("mkdtemp");

1788

goto end;

1789

}

1435

1790

tempdir_created = true;

1436

if(mkdtemp(tempdir) == NULL){

1437

tempdir_created = false;

1438

perror("mkdtemp");

1439

goto end;

1440

}

1441

1791

1442

1792

if(quit_now){

1443

1793

goto end;

1485

1835

1486

1836

port = (uint16_t)tmpmax;

1487

1837

*address = '\0';

1488

address = connect_to;

1489

1838

/* Colon in address indicates IPv6 */

1490

1839

int af;

1491

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

1840

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

1492

1841

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

}

1493

1848

} else {

1494

1849

af = AF_INET;

1495

1850

}

1851

address = connect_to;

1496

1852

1497

1853

if(quit_now){

1498

1854

goto end;

1499

1855

}

1500

1856

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 {

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){

1523

1870

exitcode = EXIT_SUCCESS;

1524

1871

}

1872

1525

1873

goto end;

1526

1874

}

1527

1875

1579

1927

if(debug){

1580

1928

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

1581

1929

}

1582

1583

avahi_simple_poll_loop(mc.simple_poll);

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

}

1584

1937

1585

1938

end:

1586

1939

1607

1960

if(gpgme_initialized){

1608

1961

gpgme_release(mc.ctx);

1609

1962

}

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

}

1610

1974

1611

1975

/* Take down the network interface */

1612

1976

if(take_down_interface){

1614

1978

errno = 0;

1615

1979

ret = seteuid(0);

1616

1980

if(ret == -1){

1617

perror("seteuid");

1981

perror_plus("seteuid");

1618

1982

}

1619

1983

if(geteuid() == 0){

1620

1984

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

1621

1985

if(ret == -1){

1622

perror("ioctl SIOCGIFFLAGS");

1986

perror_plus("ioctl SIOCGIFFLAGS");

1623

1987

} else if(network.ifr_flags & IFF_UP) {

1624

1988

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

1625

1989

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

1626

1990

if(ret == -1){

1627

perror("ioctl SIOCSIFFLAGS");

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1628

1992

}

1629

1993

}

1630

1994

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

1631

1995

if(ret == -1){

1632

perror("close");

1996

perror_plus("close");

1633

1997

}

1634

1998

/* Lower privileges permanently */

1635

1999

errno = 0;

1636

2000

ret = setuid(uid);

1637

2001

if(ret == -1){

1638

perror("setuid");

2002

perror_plus("setuid");

1639

2003

}

1640

2004

}

1641

2005

}

1642

2006

1643

/* Removes the temp directory used by GPGME */

2007

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

1644

2008

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

}

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];

1665

2016

char *fullname = NULL;

1666

2017

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

1667

2018

direntry->d_name);

1668

2019

if(ret < 0){

1669

perror("asprintf");

2020

perror_plus("asprintf");

1670

2021

continue;

1671

2022

}

1672

2023

ret = remove(fullname);

1676

2027

}

1677

2028

free(fullname);

1678

2029

}

1679

closedir(d);

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");

1680

2036

}

1681

2037

ret = rmdir(tempdir);

1682

2038

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

1683

perror("rmdir");

2039

perror_plus("rmdir");

1684

2040

}

1685

2041

}

1686

2042

1691

2047

&old_sigterm_action,

1692

2048

NULL));

1693

2049

if(ret == -1){

1694

perror("sigaction");

2050

perror_plus("sigaction");

1695

2051

}

1696

2052

do {

1697

2053

ret = raise(signal_received);

1698

2054

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

1699

2055

if(ret != 0){

1700

perror("raise");

2056

perror_plus("raise");

1701

2057

abort();

1702

2058

}

1703

2059

TEMP_FAILURE_RETRY(pause());