/mandos/release : revision 237.15.2

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@fukt.bsnet.se>.

29

* Contact the authors at <mandos@recompile.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 */

65

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

66

program_invocation_short_name */

66

67

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

67

68

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

68

69

SIOCSIFFLAGS, if_indextoname(),

73

74

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

74

75

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

75

76

setgid(), pause() */

76

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

77

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

77

78

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

78

79

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

79

80

argp_state, struct argp,

126

127

bool debug = false;

127

128

static const char mandos_protocol_version[] = "1";

128

129

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

129

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

130

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

130

131

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

131

132

char *connect_to = NULL;

132

133

134

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

135

typedef struct server{

136

const char *ip;

137

uint16_t port;

138

AvahiIfIndex if_index;

139

int af;

140

struct timespec last_seen;

141

struct server *next;

142

struct server *prev;

143

} server;

144

133

145

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

134

146

typedef struct {

135

147

AvahiSimplePoll *simple_poll;

139

151

gnutls_dh_params_t dh_params;

140

152

const char *priority;

141

153

gpgme_ctx_t ctx;

154

server *current_server;

142

155

} mandos_context;

143

156

144

157

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

145

158

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

146

159

.dh_bits = 1024, .priority = "SECURE256"

147

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

160

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

161

.current_server = NULL };

148

162

149

163

sig_atomic_t quit_now = 0;

150

164

int signal_received = 0;

151

165

166

/* Function to use when printing errors */

167

void perror_plus(const char *print_text){

168

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

169

program_invocation_short_name);

170

perror(print_text);

171

}

172

152

173

/*

153

174

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

154

175

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

166

187

return buffer_capacity;

167

188

}

168

189

190

/* 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

169

228

/*

170

229

* Initialize GPGME.

171

230

*/

185

244

186

245

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

187

246

if(fd == -1){

188

perror("open");

247

perror_plus("open");

189

248

return false;

190

249

}

191

250

205

264

206

265

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

207

266

if(ret == -1){

208

perror("close");

267

perror_plus("close");

209

268

}

210

269

gpgme_data_release(pgp_data);

211

270

return true;

224

283

return false;

225

284

}

226

285

227

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

286

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

228

287

rc = gpgme_get_engine_info(&engine_info);

229

288

if(rc != GPG_ERR_NO_ERROR){

230

289

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

336

395

337

396

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

338

397

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

339

perror("gpgme_data_seek");

398

perror_plus("gpgme_data_seek");

340

399

plaintext_length = -1;

341

400

goto decrypt_end;

342

401

}

347

406

(size_t)plaintext_length,

348

407

plaintext_capacity);

349

408

if(plaintext_capacity == 0){

350

perror("incbuffer");

409

perror_plus("incbuffer");

351

410

plaintext_length = -1;

352

411

goto decrypt_end;

353

412

}

360

419

break;

361

420

}

362

421

if(ret < 0){

363

perror("gpgme_data_read");

422

perror_plus("gpgme_data_read");

364

423

plaintext_length = -1;

365

424

goto decrypt_end;

366

425

}

423

482

}

424

483

425

484

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

427

486

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

487

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

432

488

safer_gnutls_strerror(ret));

433

489

gnutls_global_deinit();

434

490

return -1;

589

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

646

if(tcp_sd < 0){

591

647

int e = errno;

592

perror("socket");

648

perror_plus("socket");

593

649

errno = e;

594

650

goto mandos_end;

595

651

}

609

665

}

610

666

if(ret < 0 ){

611

667

int e = errno;

612

perror("inet_pton");

668

perror_plus("inet_pton");

613

669

errno = e;

614

670

goto mandos_end;

615

671

}

651

707

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

652

708

char interface[IF_NAMESIZE];

653

709

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

654

perror("if_indextoname");

710

perror_plus("if_indextoname");

655

711

} else {

656

712

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

657

713

ip, interface, port);

671

727

sizeof(addrstr));

672

728

}

673

729

if(pcret == NULL){

674

perror("inet_ntop");

730

perror_plus("inet_ntop");

675

731

} else {

676

732

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

677

733

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

692

748

if(ret < 0){

693

749

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

694

750

int e = errno;

695

perror("connect");

751

perror_plus("connect");

696

752

errno = e;

697

753

}

698

754

goto mandos_end;

711

767

out_size - written));

712

768

if(ret == -1){

713

769

int e = errno;

714

perror("write");

770

perror_plus("write");

715

771

errno = e;

716

772

goto mandos_end;

717

773

}

742

798

goto mandos_end;

743

799

}

744

800

801

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

745

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

746

803

747

804

if(quit_now){

784

841

buffer_capacity);

785

842

if(buffer_capacity == 0){

786

843

int e = errno;

787

perror("incbuffer");

844

perror_plus("incbuffer");

788

845

errno = e;

789

846

goto mandos_end;

790

847

}

895

952

if(e == 0){

896

953

e = errno;

897

954

}

898

perror("close");

955

perror_plus("close");

899

956

}

900

957

gnutls_deinit(session);

958

errno = e;

901

959

if(quit_now){

902

e = EINTR;

960

errno = EINTR;

903

961

retval = -1;

904

962

}

905

errno = e;

906

963

}

907

964

return retval;

908

965

}

951

1008

avahi_proto_to_af(proto));

952

1009

if(ret == 0){

953

1010

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

954

1014

}

955

1015

}

956

1016

}

1010

1070

}

1011

1071

}

1012

1072

1013

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

1073

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

1014

1074

static void handle_sigterm(int sig){

1015

1075

if(quit_now){

1016

1076

return;

1018

1078

quit_now = 1;

1019

1079

signal_received = sig;

1020

1080

int old_errno = errno;

1081

/* set main loop to exit */

1021

1082

if(mc.simple_poll != NULL){

1022

1083

avahi_simple_poll_quit(mc.simple_poll);

1023

1084

}

1024

1085

errno = old_errno;

1025

1086

}

1026

1087

1027

/*

1028

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

1029

* corresponds to an acceptable network device.

1030

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

1031

*/

1032

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

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

1042

return 0;

1043

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

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

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1070

break;

1071

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1088

bool get_flags(const char *ifname, struct ifreq *ifr){

1089

int ret;

1090

1091

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

1092

if(s < 0){

1093

perror_plus("socket");

1094

return false;

1095

}

1096

strcpy(ifr->ifr_name, ifname);

1097

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1098

if(ret == -1){

1081

1099

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1100

perror_plus("ioctl SIOCGIFFLAGS");

1084

1101

}

1085

free(flagstring);

1086

return 0;

1102

return false;

1087

1103

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1104

return true;

1105

}

1106

1107

bool good_flags(const char *ifname, const struct ifreq *ifr){

1108

1090

1109

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1110

if(ifr->ifr_flags & IFF_LOOPBACK){

1092

1111

if(debug){

1093

1112

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

1094

if_entry->d_name);

1113

ifname);

1095

1114

}

1096

return 0;

1115

return false;

1097

1116

}

1098

1117

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

1099

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

1118

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

1100

1119

if(debug){

1101

1120

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

1102

if_entry->d_name);

1121

ifname);

1103

1122

}

1104

return 1;

1123

return true;

1105

1124

}

1106

1125

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

1107

if(not (flags & IFF_BROADCAST)){

1126

if(not (ifr->ifr_flags & IFF_BROADCAST)){

1108

1127

if(debug){

1109

1128

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1129

ifname);

1130

}

1131

return false;

1132

}

1133

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

1134

if(ifr->ifr_flags & IFF_NOARP){

1135

if(debug){

1136

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

1137

}

1138

return false;

1139

}

1140

1114

1141

/* Accept this device */

1115

1142

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

1143

fprintf(stderr, "Interface \"%s\" is good\n", ifname);

1144

}

1145

return true;

1146

}

1147

1148

/*

1149

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

1150

* corresponds to an acceptable network device.

1151

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

1152

*/

1153

int good_interface(const struct dirent *if_entry){

1154

int ret;

1155

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

1156

return 0;

1157

}

1158

struct ifreq ifr;

1159

1160

if(not get_flags(if_entry->d_name, &ifr)){

1161

return 0;

1162

}

1163

1164

if(not good_flags(if_entry->d_name, &ifr)){

1165

return 0;

1166

}

1167

return 1;

1168

}

1169

1170

int notdotentries(const struct dirent *direntry){

1171

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

1172

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

1173

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

1174

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

1175

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

1176

return 0;

1177

}

1178

return 1;

1179

}

1180

1181

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1182

int ret;

1183

struct timespec now;

1184

struct timespec waited_time;

1185

intmax_t block_time;

1186

1187

while(true){

1188

if(mc.current_server == NULL){

1189

if (debug){

1190

fprintf(stderr,

1191

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

1192

}

1193

ret = avahi_simple_poll_iterate(s, -1);

1194

} else {

1195

if (debug){

1196

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

1197

" or wait\n");

1198

}

1199

/* the current time */

1200

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1201

if(ret == -1){

1202

perror_plus("clock_gettime");

1203

return -1;

1204

}

1205

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

1206

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

1207

waited_time.tv_sec = (now.tv_sec

1208

- mc.current_server->last_seen.tv_sec);

1209

waited_time.tv_nsec = (now.tv_nsec

1210

- mc.current_server->last_seen.tv_nsec);

1211

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

1212

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

1213

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

1214

block_time = ((retry_interval

1215

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

1216

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

1217

1218

if (debug){

1219

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

1220

}

1221

1222

if(block_time <= 0){

1223

ret = start_mandos_communication(mc.current_server->ip,

1224

mc.current_server->port,

1225

mc.current_server->if_index,

1226

mc.current_server->af);

1227

if(ret == 0){

1228

avahi_simple_poll_quit(mc.simple_poll);

1229

return 0;

1230

}

1231

ret = clock_gettime(CLOCK_MONOTONIC,

1232

&mc.current_server->last_seen);

1233

if(ret == -1){

1234

perror_plus("clock_gettime");

1235

return -1;

1236

}

1237

mc.current_server = mc.current_server->next;

1238

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

1239

servers, but don't block */

1240

}

1241

1242

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

1243

}

1244

if(ret != 0){

1245

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

1246

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

1247

}

1248

}

1249

}

1120

1250

}

1121

1251

1122

1252

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

1141

1271

bool gnutls_initialized = false;

1142

1272

bool gpgme_initialized = false;

1143

1273

float delay = 2.5f;

1274

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

1275

retrying the same server again */

1144

1276

1145

1277

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1278

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1284

errno = 0;

1153

1285

ret = setgid(gid);

1154

1286

if(ret == -1){

1155

perror("setgid");

1287

perror_plus("setgid");

1156

1288

}

1157

1289

1158

1290

/* Lower user privileges (temporarily) */

1159

1291

errno = 0;

1160

1292

ret = seteuid(uid);

1161

1293

if(ret == -1){

1162

perror("seteuid");

1294

perror_plus("seteuid");

1163

1295

}

1164

1296

1165

1297

if(quit_now){

1200

1332

.arg = "SECONDS",

1201

1333

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

1202

1334

.group = 2 },

1335

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

1336

.arg = "SECONDS",

1337

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

1338

.group = 2 },

1203

1339

/*

1204

1340

* These reproduce what we would get without ARGP_NO_HELP

1205

1341

*/

1249

1385

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

1250

1386

argp_error(state, "Bad delay");

1251

1387

}

1388

case 132: /* --retry */

1389

errno = 0;

1390

retry_interval = strtod(arg, &tmp);

1391

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

1392

or (retry_interval * 1000) > INT_MAX

1393

or retry_interval < 0){

1394

argp_error(state, "Bad retry interval");

1395

}

1252

1396

break;

1253

1397

/*

1254

1398

* These reproduce what we would get without ARGP_NO_HELP

1282

1426

case ENOMEM:

1283

1427

default:

1284

1428

errno = ret;

1285

perror("argp_parse");

1429

perror_plus("argp_parse");

1286

1430

exitcode = EX_OSERR;

1287

1431

goto end;

1288

1432

case EINVAL:

1290

1434

goto end;

1291

1435

}

1292

1436

}

1437

1438

{

1439

/* Work around Debian bug #633582:

1440

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

1441

struct stat st;

1442

1443

/* Re-raise priviliges */

1444

errno = 0;

1445

ret = seteuid(0);

1446

if(ret == -1){

1447

perror_plus("seteuid");

1448

}

1449

1450

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

1451

int seckey_fd = open(seckey, O_RDONLY);

1452

if(seckey_fd == -1){

1453

perror_plus("open");

1454

} else {

1455

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

1456

if(ret == -1){

1457

perror_plus("fstat");

1458

} else {

1459

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

1460

ret = fchown(seckey_fd, uid, gid);

1461

if(ret == -1){

1462

perror_plus("fchown");

1463

}

1464

}

1465

}

1466

TEMP_FAILURE_RETRY(close(seckey_fd));

1467

}

1468

}

1469

1470

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

1471

int pubkey_fd = open(pubkey, O_RDONLY);

1472

if(pubkey_fd == -1){

1473

perror_plus("open");

1474

} else {

1475

ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_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(pubkey_fd, uid, gid);

1481

if(ret == -1){

1482

perror_plus("fchown");

1483

}

1484

}

1485

}

1486

TEMP_FAILURE_RETRY(close(pubkey_fd));

1487

}

1488

}

1489

1490

/* Lower privileges */

1491

errno = 0;

1492

ret = seteuid(uid);

1493

if(ret == -1){

1494

perror_plus("seteuid");

1495

}

1496

}

1293

1497

1294

1498

if(not debug){

1295

1499

avahi_set_log_function(empty_log);

1306

1510

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

1307

1511

}

1308

1512

if(interface == NULL){

1309

perror("malloc");

1513

perror_plus("malloc");

1310

1514

free(direntries);

1311

1515

exitcode = EXIT_FAILURE;

1312

1516

goto end;

1334

1538

sigemptyset(&sigterm_action.sa_mask);

1335

1539

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

1336

1540

if(ret == -1){

1337

perror("sigaddset");

1541

perror_plus("sigaddset");

1338

1542

exitcode = EX_OSERR;

1339

1543

goto end;

1340

1544

}

1341

1545

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

1342

1546

if(ret == -1){

1343

perror("sigaddset");

1547

perror_plus("sigaddset");

1344

1548

exitcode = EX_OSERR;

1345

1549

goto end;

1346

1550

}

1347

1551

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

1348

1552

if(ret == -1){

1349

perror("sigaddset");

1553

perror_plus("sigaddset");

1350

1554

exitcode = EX_OSERR;

1351

1555

goto end;

1352

1556

}

1356

1560

*/

1357

1561

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

1358

1562

if(ret == -1){

1359

perror("sigaction");

1563

perror_plus("sigaction");

1360

1564

return EX_OSERR;

1361

1565

}

1362

1566

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

1567

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

1364

1568

if(ret == -1){

1365

perror("sigaction");

1569

perror_plus("sigaction");

1366

1570

exitcode = EX_OSERR;

1367

1571

goto end;

1368

1572

}

1369

1573

}

1370

1574

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

1371

1575

if(ret == -1){

1372

perror("sigaction");

1576

perror_plus("sigaction");

1373

1577

return EX_OSERR;

1374

1578

}

1375

1579

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

1580

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

1377

1581

if(ret == -1){

1378

perror("sigaction");

1582

perror_plus("sigaction");

1379

1583

exitcode = EX_OSERR;

1380

1584

goto end;

1381

1585

}

1382

1586

}

1383

1587

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

1384

1588

if(ret == -1){

1385

perror("sigaction");

1589

perror_plus("sigaction");

1386

1590

return EX_OSERR;

1387

1591

}

1388

1592

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

1593

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

1390

1594

if(ret == -1){

1391

perror("sigaction");

1595

perror_plus("sigaction");

1392

1596

exitcode = EX_OSERR;

1393

1597

goto end;

1394

1598

}

1411

1615

errno = 0;

1412

1616

ret = seteuid(0);

1413

1617

if(ret == -1){

1414

perror("seteuid");

1618

perror_plus("seteuid");

1415

1619

}

1416

1620

1417

1621

#ifdef __linux__

1421

1625

bool restore_loglevel = true;

1422

1626

if(ret == -1){

1423

1627

restore_loglevel = false;

1424

perror("klogctl");

1628

perror_plus("klogctl");

1425

1629

}

1426

1630

#endif /* __linux__ */

1427

1631

1428

1632

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

1633

if(sd < 0){

1430

perror("socket");

1634

perror_plus("socket");

1431

1635

exitcode = EX_OSERR;

1432

1636

#ifdef __linux__

1433

1637

if(restore_loglevel){

1434

1638

ret = klogctl(7, NULL, 0);

1435

1639

if(ret == -1){

1436

perror("klogctl");

1640

perror_plus("klogctl");

1437

1641

}

1438

1642

}

1439

1643

#endif /* __linux__ */

1441

1645

errno = 0;

1442

1646

ret = seteuid(uid);

1443

1647

if(ret == -1){

1444

perror("seteuid");

1648

perror_plus("seteuid");

1445

1649

}

1446

1650

goto end;

1447

1651

}

1448

1652

strcpy(network.ifr_name, interface);

1449

1653

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

1450

1654

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1655

perror_plus("ioctl SIOCGIFFLAGS");

1452

1656

#ifdef __linux__

1453

1657

if(restore_loglevel){

1454

1658

ret = klogctl(7, NULL, 0);

1455

1659

if(ret == -1){

1456

perror("klogctl");

1660

perror_plus("klogctl");

1457

1661

}

1458

1662

}

1459

1663

#endif /* __linux__ */

1462

1666

errno = 0;

1463

1667

ret = seteuid(uid);

1464

1668

if(ret == -1){

1465

perror("seteuid");

1669

perror_plus("seteuid");

1466

1670

}

1467

1671

goto end;

1468

1672

}

1472

1676

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

1473

1677

if(ret == -1){

1474

1678

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1679

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1476

1680

exitcode = EX_OSERR;

1477

1681

#ifdef __linux__

1478

1682

if(restore_loglevel){

1479

1683

ret = klogctl(7, NULL, 0);

1480

1684

if(ret == -1){

1481

perror("klogctl");

1685

perror_plus("klogctl");

1482

1686

}

1483

1687

}

1484

1688

#endif /* __linux__ */

1486

1690

errno = 0;

1487

1691

ret = seteuid(uid);

1488

1692

if(ret == -1){

1489

perror("seteuid");

1693

perror_plus("seteuid");

1490

1694

}

1491

1695

goto end;

1492

1696

}

1493

1697

}

1494

/* sleep checking until interface is running */

1698

/* Sleep checking until interface is running.

1699

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

1495

1700

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

1496

1701

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

1497

1702

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1703

perror_plus("ioctl SIOCGIFFLAGS");

1499

1704

} else if(network.ifr_flags & IFF_RUNNING){

1500

1705

break;

1501

1706

}

1502

1707

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

1708

ret = nanosleep(&sleeptime, NULL);

1504

1709

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

1505

perror("nanosleep");

1710

perror_plus("nanosleep");

1506

1711

}

1507

1712

}

1508

1713

if(not take_down_interface){

1509

1714

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

1510

1715

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

1511

1716

if(ret == -1){

1512

perror("close");

1717

perror_plus("close");

1513

1718

}

1514

1719

}

1515

1720

#ifdef __linux__

1517

1722

/* Restores kernel loglevel to default */

1518

1723

ret = klogctl(7, NULL, 0);

1519

1724

if(ret == -1){

1520

perror("klogctl");

1725

perror_plus("klogctl");

1521

1726

}

1522

1727

}

1523

1728

#endif /* __linux__ */

1527

1732

/* Lower privileges */

1528

1733

ret = seteuid(uid);

1529

1734

if(ret == -1){

1530

perror("seteuid");

1735

perror_plus("seteuid");

1531

1736

}

1532

1737

} else {

1533

1738

/* Lower privileges permanently */

1534

1739

ret = setuid(uid);

1535

1740

if(ret == -1){

1536

perror("setuid");

1741

perror_plus("setuid");

1537

1742

}

1538

1743

}

1539

1744

}

1555

1760

goto end;

1556

1761

}

1557

1762

1763

if(mkdtemp(tempdir) == NULL){

1764

perror_plus("mkdtemp");

1765

goto end;

1766

}

1558

1767

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

1562

goto end;

1563

}

1564

1768

1565

1769

if(quit_now){

1566

1770

goto end;

1608

1812

1609

1813

port = (uint16_t)tmpmax;

1610

1814

*address = '\0';

1611

address = connect_to;

1612

1815

/* Colon in address indicates IPv6 */

1613

1816

int af;

1614

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

1817

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

1615

1818

af = AF_INET6;

1819

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

1820

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

1821

{

1822

connect_to++;

1823

address[-1] = '\0';

1824

}

1616

1825

} else {

1617

1826

af = AF_INET;

1618

1827

}

1828

address = connect_to;

1619

1829

1620

1830

if(quit_now){

1621

1831

goto end;

1622

1832

}

1623

1833

1624

1834

while(not quit_now){

1625

1835

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

1626

1836

if(quit_now or ret == 0){

1627

1837

break;

1628

1838

}

1629

sleep(15);

1630

};

1631

1839

if(debug){

1840

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

1841

(int)retry_interval);

1842

}

1843

sleep((int)retry_interval);

1844

}

1845

1632

1846

if (not quit_now){

1633

1847

exitcode = EXIT_SUCCESS;

1634

1848

}

1690

1904

if(debug){

1691

1905

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

1692

1906

}

1693

1694

avahi_simple_poll_loop(mc.simple_poll);

1907

1908

ret = avahi_loop_with_timeout(mc.simple_poll,

1909

(int)(retry_interval * 1000));

1910

if(debug){

1911

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

1912

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

1913

}

1695

1914

1696

1915

end:

1697

1916

1718

1937

if(gpgme_initialized){

1719

1938

gpgme_release(mc.ctx);

1720

1939

}

1940

1941

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

1942

has seen */

1943

if(mc.current_server != NULL){

1944

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

1945

while(mc.current_server != NULL){

1946

server *next = mc.current_server->next;

1947

free(mc.current_server);

1948

mc.current_server = next;

1949

}

1950

}

1721

1951

1722

1952

/* Take down the network interface */

1723

1953

if(take_down_interface){

1725

1955

errno = 0;

1726

1956

ret = seteuid(0);

1727

1957

if(ret == -1){

1728

perror("seteuid");

1958

perror_plus("seteuid");

1729

1959

}

1730

1960

if(geteuid() == 0){

1731

1961

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

1732

1962

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1963

perror_plus("ioctl SIOCGIFFLAGS");

1734

1964

} else if(network.ifr_flags & IFF_UP) {

1735

1965

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

1736

1966

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

1737

1967

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1968

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1739

1969

}

1740

1970

}

1741

1971

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

1742

1972

if(ret == -1){

1743

perror("close");

1973

perror_plus("close");

1744

1974

}

1745

1975

/* Lower privileges permanently */

1746

1976

errno = 0;

1747

1977

ret = setuid(uid);

1748

1978

if(ret == -1){

1749

perror("setuid");

1979

perror_plus("setuid");

1750

1980

}

1751

1981

}

1752

1982

}

1753

1983

1754

/* Removes the temp directory used by GPGME */

1984

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

1755

1985

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

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

1772

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

1773

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

1774

continue;

1775

}

1986

struct dirent **direntries = NULL;

1987

struct dirent *direntry = NULL;

1988

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

1989

alphasort);

1990

if (numentries > 0){

1991

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

1992

direntry = direntries[i];

1776

1993

char *fullname = NULL;

1777

1994

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

1778

1995

direntry->d_name);

1779

1996

if(ret < 0){

1780

perror("asprintf");

1997

perror_plus("asprintf");

1781

1998

continue;

1782

1999

}

1783

2000

ret = remove(fullname);

1787

2004

}

1788

2005

free(fullname);

1789

2006

}

1790

closedir(d);

2007

}

2008

2009

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

2010

free(direntries);

2011

if (numentries == -1){

2012

perror_plus("scandir");

1791

2013

}

1792

2014

ret = rmdir(tempdir);

1793

2015

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

1794

perror("rmdir");

2016

perror_plus("rmdir");

1795

2017

}

1796

2018

}

1797

2019

1802

2024

&old_sigterm_action,

1803

2025

NULL));

1804

2026

if(ret == -1){

1805

perror("sigaction");

2027

perror_plus("sigaction");

1806

2028

}

1807

2029

do {

1808

2030

ret = raise(signal_received);

1809

2031

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

1810

2032

if(ret != 0){

1811

perror("raise");

2033

perror_plus("raise");

1812

2034

abort();

1813

2035

}

1814

2036

TEMP_FAILURE_RETRY(pause());