/mandos/release : revision 237.2.158

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

43

stdout, ferror(), remove() */

44

#include <stdint.h> /* uint16_t, uint32_t */

45

#include <stddef.h> /* NULL, size_t, ssize_t */

46

#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),

47

strtof(), abort() */

46

#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,

47

srand(), strtof(), abort() */

48

#include <stdbool.h> /* bool, false, true */

49

#include <string.h> /* memset(), strcmp(), strlen(),

50

strerror(), asprintf(), strcpy() */

62

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

63

strtoimax() */

64

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

65

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

66

program_invocation_short_name */

67

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

65

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

66

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

68

67

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

69

68

SIOCSIFFLAGS, if_indextoname(),

70

69

if_nametoindex(), IF_NAMESIZE */

74

73

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

75

74

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

76

75

setgid(), pause() */

77

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

76

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

78

77

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

79

78

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

80

79

argp_state, struct argp,

83

82

#include <signal.h> /* sigemptyset(), sigaddset(),

84

83

sigaction(), SIGTERM, sig_atomic_t,

85

84

raise() */

86

#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

85

#include <sysexits.h> /* EX_OSERR, EX_USAGE */

88

86

89

87

#ifdef __linux__

90

88

#include <sys/klog.h> /* klogctl() */

128

126

static const char mandos_protocol_version[] = "1";

129

127

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

130

128

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;

144

129

145

130

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

146

131

typedef struct {

151

136

gnutls_dh_params_t dh_params;

152

137

const char *priority;

153

138

gpgme_ctx_t ctx;

154

server *current_server;

155

139

} mandos_context;

156

140

157

141

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

158

142

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

159

143

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

144

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

162

145

163

146

sig_atomic_t quit_now = 0;

164

147

int signal_received = 0;

165

148

166

/* Function to use when printing errors */

167

void perror_plus(const char *print_text){

168

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

169

program_invocation_short_name);

170

perror(print_text);

171

}

172

173

149

/*

174

150

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

175

151

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

187

163

return buffer_capacity;

188

164

}

189

165

190

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

191

int add_server(const char *ip, uint16_t port,

192

AvahiIfIndex if_index,

193

int af){

194

int ret;

195

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

196

if(new_server == NULL){

197

perror_plus("malloc");

198

return -1;

199

}

200

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

201

.port = port,

202

.if_index = if_index,

203

.af = af };

204

if(new_server->ip == NULL){

205

perror_plus("strdup");

206

return -1;

207

}

208

/* Special case of first server */

209

if (mc.current_server == NULL){

210

new_server->next = new_server;

211

new_server->prev = new_server;

212

mc.current_server = new_server;

213

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

214

} else {

215

new_server->next = mc.current_server;

216

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

217

new_server->prev->next = new_server;

218

mc.current_server->prev = new_server;

219

}

220

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

221

if(ret == -1){

222

perror_plus("clock_gettime");

223

return -1;

224

}

225

return 0;

226

}

227

228

166

/*

229

167

* Initialize GPGME.

230

168

*/

244

182

245

183

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

246

184

if(fd == -1){

247

perror_plus("open");

185

perror("open");

248

186

return false;

249

187

}

250

188

264

202

265

203

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

266

204

if(ret == -1){

267

perror_plus("close");

205

perror("close");

268

206

}

269

207

gpgme_data_release(pgp_data);

270

208

return true;

283

221

return false;

284

222

}

285

223

286

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

224

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

287

225

rc = gpgme_get_engine_info(&engine_info);

288

226

if(rc != GPG_ERR_NO_ERROR){

289

227

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

395

333

396

334

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

397

335

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

398

perror_plus("gpgme_data_seek");

336

perror("gpgme_data_seek");

399

337

plaintext_length = -1;

400

338

goto decrypt_end;

401

339

}

406

344

(size_t)plaintext_length,

407

345

plaintext_capacity);

408

346

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

347

perror("incbuffer");

410

348

plaintext_length = -1;

411

349

goto decrypt_end;

412

350

}

419

357

break;

420

358

}

421

359

if(ret < 0){

422

perror_plus("gpgme_data_read");

360

perror("gpgme_data_read");

423

361

plaintext_length = -1;

424

362

goto decrypt_end;

425

363

}

482

420

}

483

421

484

422

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

423

gnutls_certificate_allocate_credentials(&mc.cred);

486

424

if(ret != GNUTLS_E_SUCCESS){

487

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

425

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

426

from

427

-Wunreachable-code

428

*/

488

429

safer_gnutls_strerror(ret));

489

430

gnutls_global_deinit();

490

431

return -1;

612

553

gnutls_session_t session;

613

554

int pf; /* Protocol family */

614

555

615

errno = 0;

616

617

556

if(quit_now){

618

errno = EINTR;

619

557

return -1;

620

558

}

621

559

628

566

break;

629

567

default:

630

568

fprintf(stderr, "Bad address family: %d\n", af);

631

errno = EINVAL;

632

569

return -1;

633

570

}

634

571

644

581

645

582

tcp_sd = socket(pf, SOCK_STREAM, 0);

646

583

if(tcp_sd < 0){

647

int e = errno;

648

perror_plus("socket");

649

errno = e;

584

perror("socket");

650

585

goto mandos_end;

651

586

}

652

587

653

588

if(quit_now){

654

errno = EINTR;

655

589

goto mandos_end;

656

590

}

657

591

664

598

ret = inet_pton(af, ip, &to.in.sin_addr);

665

599

}

666

600

if(ret < 0 ){

667

int e = errno;

668

perror_plus("inet_pton");

669

errno = e;

601

perror("inet_pton");

670

602

goto mandos_end;

671

603

}

672

604

if(ret == 0){

673

int e = errno;

674

605

fprintf(stderr, "Bad address: %s\n", ip);

675

errno = e;

676

606

goto mandos_end;

677

607

}

678

608

if(af == AF_INET6){

686

616

if(if_index == AVAHI_IF_UNSPEC){

687

617

fprintf(stderr, "An IPv6 link-local address is incomplete"

688

618

" without a network interface\n");

689

errno = EINVAL;

690

619

goto mandos_end;

691

620

}

692

621

/* Set the network interface number as scope */

699

628

}

700

629

701

630

if(quit_now){

702

errno = EINTR;

703

631

goto mandos_end;

704

632

}

705

633

707

635

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

708

636

char interface[IF_NAMESIZE];

709

637

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

710

perror_plus("if_indextoname");

638

perror("if_indextoname");

711

639

} else {

712

640

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

713

641

ip, interface, port);

727

655

sizeof(addrstr));

728

656

}

729

657

if(pcret == NULL){

730

perror_plus("inet_ntop");

658

perror("inet_ntop");

731

659

} else {

732

660

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

733

661

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

736

664

}

737

665

738

666

if(quit_now){

739

errno = EINTR;

740

667

goto mandos_end;

741

668

}

742

669

746

673

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

747

674

}

748

675

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

676

perror("connect");

754

677

goto mandos_end;

755

678

}

756

679

757

680

if(quit_now){

758

errno = EINTR;

759

681

goto mandos_end;

760

682

}

761

683

766

688

ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,

767

689

out_size - written));

768

690

if(ret == -1){

769

int e = errno;

770

perror_plus("write");

771

errno = e;

691

perror("write");

772

692

goto mandos_end;

773

693

}

774

694

written += (size_t)ret;

784

704

}

785

705

786

706

if(quit_now){

787

errno = EINTR;

788

707

goto mandos_end;

789

708

}

790

709

}

794

713

}

795

714

796

715

if(quit_now){

797

errno = EINTR;

798

716

goto mandos_end;

799

717

}

800

718

801

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

802

719

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

803

720

804

721

if(quit_now){

805

errno = EINTR;

806

722

goto mandos_end;

807

723

}

808

724

809

725

do {

810

726

ret = gnutls_handshake(session);

811

727

if(quit_now){

812

errno = EINTR;

813

728

goto mandos_end;

814

729

}

815

730

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

819

734

fprintf(stderr, "*** GnuTLS Handshake failed ***\n");

820

735

gnutls_perror(ret);

821

736

}

822

errno = EPROTO;

823

737

goto mandos_end;

824

738

}

825

739

833

747

while(true){

834

748

835

749

if(quit_now){

836

errno = EINTR;

837

750

goto mandos_end;

838

751

}

839

752

840

753

buffer_capacity = incbuffer(&buffer, buffer_length,

841

754

buffer_capacity);

842

755

if(buffer_capacity == 0){

843

int e = errno;

844

perror_plus("incbuffer");

845

errno = e;

756

perror("incbuffer");

846

757

goto mandos_end;

847

758

}

848

759

849

760

if(quit_now){

850

errno = EINTR;

851

761

goto mandos_end;

852

762

}

853

763

866

776

ret = gnutls_handshake(session);

867

777

868

778

if(quit_now){

869

errno = EINTR;

870

779

goto mandos_end;

871

780

}

872

781

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

873

782

if(ret < 0){

874

783

fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");

875

784

gnutls_perror(ret);

876

errno = EPROTO;

877

785

goto mandos_end;

878

786

}

879

787

break;

881

789

fprintf(stderr, "Unknown error while reading data from"

882

790

" encrypted session with Mandos server\n");

883

791

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

errno = EIO;

885

792

goto mandos_end;

886

793

}

887

794

} else {

894

801

}

895

802

896

803

if(quit_now){

897

errno = EINTR;

898

804

goto mandos_end;

899

805

}

900

806

901

807

do {

902

808

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

903

809

if(quit_now){

904

errno = EINTR;

905

810

goto mandos_end;

906

811

}

907

812

} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);

916

821

written = 0;

917

822

while(written < (size_t) decrypted_buffer_size){

918

823

if(quit_now){

919

errno = EINTR;

920

824

goto mandos_end;

921

825

}

922

826

924

828

(size_t)decrypted_buffer_size - written,

925

829

stdout);

926

830

if(ret == 0 and ferror(stdout)){

927

int e = errno;

928

831

if(debug){

929

832

fprintf(stderr, "Error writing encrypted data: %s\n",

930

833

strerror(errno));

931

834

}

932

errno = e;

933

835

goto mandos_end;

934

836

}

935

837

written += (size_t)ret;

941

843

/* Shutdown procedure */

942

844

943

845

mandos_end:

944

{

945

int e = errno;

946

free(decrypted_buffer);

947

free(buffer);

948

if(tcp_sd >= 0){

949

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

950

}

951

if(ret == -1){

952

if(e == 0){

953

e = errno;

954

}

955

perror_plus("close");

956

}

957

gnutls_deinit(session);

958

errno = e;

959

if(quit_now){

960

errno = EINTR;

961

retval = -1;

962

}

846

free(decrypted_buffer);

847

free(buffer);

848

if(tcp_sd >= 0){

849

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

850

}

851

if(ret == -1){

852

perror("close");

853

}

854

gnutls_deinit(session);

855

if(quit_now){

856

retval = -1;

963

857

}

964

858

return retval;

965

859

}

1008

902

avahi_proto_to_af(proto));

1009

903

if(ret == 0){

1010

904

avahi_simple_poll_quit(mc.simple_poll);

1011

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1014

905

}

1015

906

}

1016

907

}

1070

961

}

1071

962

}

1072

963

1073

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

964

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

1074

965

static void handle_sigterm(int sig){

1075

966

if(quit_now){

1076

967

return;

1078

969

quit_now = 1;

1079

970

signal_received = sig;

1080

971

int old_errno = errno;

1081

/* set main loop to exit */

1082

972

if(mc.simple_poll != NULL){

1083

973

avahi_simple_poll_quit(mc.simple_poll);

1084

974

}

1085

975

errno = old_errno;

1086

976

}

1087

977

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

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

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

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

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1153

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1155

if(debug){

1156

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

1157

if_entry->d_name);

1158

}

1159

return 0;

1160

}

1161

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

1162

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

1163

if(debug){

1164

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

1165

if_entry->d_name);

1166

}

1167

return 1;

1168

}

1169

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

1170

if(not (flags & IFF_BROADCAST)){

1171

if(debug){

1172

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

1173

if_entry->d_name);

1174

}

1175

return 0;

1176

}

1177

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

1178

if(flags & IFF_NOARP){

1179

if(debug){

1180

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

1181

if_entry->d_name);

1182

}

1183

return 0;

1184

}

1185

/* Accept this device */

1186

if(debug){

1187

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

1188

if_entry->d_name);

1189

}

1190

return 1;

1191

}

1192

1193

int notdotentries(const struct dirent *direntry){

1194

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

1195

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

1196

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

1197

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

1198

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

1199

return 0;

1200

}

1201

return 1;

1202

}

1203

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1205

int ret;

1206

struct timespec now;

1207

struct timespec waited_time;

1208

intmax_t block_time;

1209

1210

while(true){

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

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

1215

}

1216

ret = avahi_simple_poll_iterate(s, -1);

1217

} else {

1218

if (debug){

1219

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

1220

" or wait\n");

1221

}

1222

/* the current time */

1223

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1224

if(ret == -1){

1225

perror_plus("clock_gettime");

1226

return -1;

1227

}

1228

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

1229

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

1230

waited_time.tv_sec = (now.tv_sec

1231

- mc.current_server->last_seen.tv_sec);

1232

waited_time.tv_nsec = (now.tv_nsec

1233

- mc.current_server->last_seen.tv_nsec);

1234

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

1235

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

1236

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

1237

block_time = ((retry_interval

1238

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

1239

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

1240

1241

if (debug){

1242

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

1243

}

1244

1245

if(block_time <= 0){

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

mc.current_server->af);

1250

if(ret == 0){

1251

avahi_simple_poll_quit(mc.simple_poll);

1252

return 0;

1253

}

1254

ret = clock_gettime(CLOCK_MONOTONIC,

1255

&mc.current_server->last_seen);

1256

if(ret == -1){

1257

perror_plus("clock_gettime");

1258

return -1;

1259

}

1260

mc.current_server = mc.current_server->next;

1261

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

1262

servers, but don't block */

1263

}

1264

1265

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

1266

}

1267

if(ret != 0){

1268

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

1269

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

1270

}

1271

}

1272

}

1273

}

1274

1275

978

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

1276

979

AvahiSServiceBrowser *sb = NULL;

1277

980

int error;

1279

982

intmax_t tmpmax;

1280

983

char *tmp;

1281

984

int exitcode = EXIT_SUCCESS;

1282

const char *interface = "";

985

const char *interface = "eth0";

1283

986

struct ifreq network;

1284

987

int sd = -1;

1285

988

bool take_down_interface = false;

1286

989

uid_t uid;

1287

990

gid_t gid;

991

char *connect_to = NULL;

1288

992

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

1289

993

bool tempdir_created = false;

1290

994

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1294

998

bool gnutls_initialized = false;

1295

999

bool gpgme_initialized = false;

1296

1000

float delay = 2.5f;

1297

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

1298

retrying the same server again */

1299

1001

1300

1002

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1301

1003

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1307

1009

errno = 0;

1308

1010

ret = setgid(gid);

1309

1011

if(ret == -1){

1310

perror_plus("setgid");

1012

perror("setgid");

1311

1013

}

1312

1014

1313

1015

/* Lower user privileges (temporarily) */

1314

1016

errno = 0;

1315

1017

ret = seteuid(uid);

1316

1018

if(ret == -1){

1317

perror_plus("seteuid");

1019

perror("seteuid");

1318

1020

}

1319

1021

1320

1022

if(quit_now){

1355

1057

.arg = "SECONDS",

1356

1058

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

1357

1059

.group = 2 },

1358

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

1359

.arg = "SECONDS",

1360

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

1361

.group = 2 },

1362

1060

/*

1363

1061

* These reproduce what we would get without ARGP_NO_HELP

1364

1062

*/

1408

1106

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

1409

1107

argp_error(state, "Bad delay");

1410

1108

}

1411

case 132: /* --retry */

1412

errno = 0;

1413

retry_interval = strtod(arg, &tmp);

1414

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

1415

or (retry_interval * 1000) > INT_MAX

1416

or retry_interval < 0){

1417

argp_error(state, "Bad retry interval");

1418

}

1419

1109

break;

1420

1110

/*

1421

1111

* These reproduce what we would get without ARGP_NO_HELP

1449

1139

case ENOMEM:

1450

1140

default:

1451

1141

errno = ret;

1452

perror_plus("argp_parse");

1142

perror("argp_parse");

1453

1143

exitcode = EX_OSERR;

1454

1144

goto end;

1455

1145

case EINVAL:

1457

1147

goto end;

1458

1148

}

1459

1149

}

1460

1461

{

1462

/* Work around Debian bug #633582:

1463

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

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

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

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

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

1519

}

1520

1150

1521

1151

if(not debug){

1522

1152

avahi_set_log_function(empty_log);

1523

1153

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

1549

1154

1550

1155

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

1551

1156

from the signal handler */

1554

1159

mc.simple_poll = avahi_simple_poll_new();

1555

1160

if(mc.simple_poll == NULL){

1556

1161

fprintf(stderr, "Avahi: Failed to create simple poll object.\n");

1557

exitcode = EX_UNAVAILABLE;

1162

exitcode = EXIT_FAILURE;

1558

1163

goto end;

1559

1164

}

1560

1165

1561

1166

sigemptyset(&sigterm_action.sa_mask);

1562

1167

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

1563

1168

if(ret == -1){

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1169

perror("sigaddset");

1170

exitcode = EXIT_FAILURE;

1566

1171

goto end;

1567

1172

}

1568

1173

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

1569

1174

if(ret == -1){

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1175

perror("sigaddset");

1176

exitcode = EXIT_FAILURE;

1572

1177

goto end;

1573

1178

}

1574

1179

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

1575

1180

if(ret == -1){

1576

perror_plus("sigaddset");

1577

exitcode = EX_OSERR;

1181

perror("sigaddset");

1182

exitcode = EXIT_FAILURE;

1578

1183

goto end;

1579

1184

}

1580

1185

/* Need to check if the handler is SIG_IGN before handling:

1583

1188

*/

1584

1189

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

1585

1190

if(ret == -1){

1586

perror_plus("sigaction");

1587

return EX_OSERR;

1191

perror("sigaction");

1192

return EXIT_FAILURE;

1588

1193

}

1589

1194

if(old_sigterm_action.sa_handler != SIG_IGN){

1590

1195

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

1591

1196

if(ret == -1){

1592

perror_plus("sigaction");

1593

exitcode = EX_OSERR;

1197

perror("sigaction");

1198

exitcode = EXIT_FAILURE;

1594

1199

goto end;

1595

1200

}

1596

1201

}

1597

1202

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

1598

1203

if(ret == -1){

1599

perror_plus("sigaction");

1600

return EX_OSERR;

1204

perror("sigaction");

1205

return EXIT_FAILURE;

1601

1206

}

1602

1207

if(old_sigterm_action.sa_handler != SIG_IGN){

1603

1208

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

1604

1209

if(ret == -1){

1605

perror_plus("sigaction");

1606

exitcode = EX_OSERR;

1210

perror("sigaction");

1211

exitcode = EXIT_FAILURE;

1607

1212

goto end;

1608

1213

}

1609

1214

}

1610

1215

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

1611

1216

if(ret == -1){

1612

perror_plus("sigaction");

1613

return EX_OSERR;

1217

perror("sigaction");

1218

return EXIT_FAILURE;

1614

1219

}

1615

1220

if(old_sigterm_action.sa_handler != SIG_IGN){

1616

1221

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

1617

1222

if(ret == -1){

1618

perror_plus("sigaction");

1619

exitcode = EX_OSERR;

1223

perror("sigaction");

1224

exitcode = EXIT_FAILURE;

1620

1225

goto end;

1621

1226

}

1622

1227

}

1623

1228

1624

1229

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

1625

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

1230

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

1626

1231

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

1232

if(if_index == 0){

1628

1233

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

1629

exitcode = EX_UNAVAILABLE;

1234

exitcode = EXIT_FAILURE;

1630

1235

goto end;

1631

1236

}

1632

1237

1638

1243

errno = 0;

1639

1244

ret = seteuid(0);

1640

1245

if(ret == -1){

1641

perror_plus("seteuid");

1246

perror("seteuid");

1642

1247

}

1643

1248

1644

1249

#ifdef __linux__

1648

1253

bool restore_loglevel = true;

1649

1254

if(ret == -1){

1650

1255

restore_loglevel = false;

1651

perror_plus("klogctl");

1256

perror("klogctl");

1652

1257

}

1653

1258

#endif /* __linux__ */

1654

1259

1655

1260

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

1261

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1262

perror("socket");

1263

exitcode = EXIT_FAILURE;

1659

1264

#ifdef __linux__

1660

1265

if(restore_loglevel){

1661

1266

ret = klogctl(7, NULL, 0);

1662

1267

if(ret == -1){

1663

perror_plus("klogctl");

1268

perror("klogctl");

1664

1269

}

1665

1270

}

1666

1271

#endif /* __linux__ */

1668

1273

errno = 0;

1669

1274

ret = seteuid(uid);

1670

1275

if(ret == -1){

1671

perror_plus("seteuid");

1276

perror("seteuid");

1672

1277

}

1673

1278

goto end;

1674

1279

}

1675

1280

strcpy(network.ifr_name, interface);

1676

1281

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

1677

1282

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1283

perror("ioctl SIOCGIFFLAGS");

1679

1284

#ifdef __linux__

1680

1285

if(restore_loglevel){

1681

1286

ret = klogctl(7, NULL, 0);

1682

1287

if(ret == -1){

1683

perror_plus("klogctl");

1288

perror("klogctl");

1684

1289

}

1685

1290

}

1686

1291

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1292

exitcode = EXIT_FAILURE;

1688

1293

/* Lower privileges */

1689

1294

errno = 0;

1690

1295

ret = seteuid(uid);

1691

1296

if(ret == -1){

1692

perror_plus("seteuid");

1297

perror("seteuid");

1693

1298

}

1694

1299

goto end;

1695

1300

}

1699

1304

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

1700

1305

if(ret == -1){

1701

1306

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1307

perror("ioctl SIOCSIFFLAGS");

1308

exitcode = EXIT_FAILURE;

1704

1309

#ifdef __linux__

1705

1310

if(restore_loglevel){

1706

1311

ret = klogctl(7, NULL, 0);

1707

1312

if(ret == -1){

1708

perror_plus("klogctl");

1313

perror("klogctl");

1709

1314

}

1710

1315

}

1711

1316

#endif /* __linux__ */

1713

1318

errno = 0;

1714

1319

ret = seteuid(uid);

1715

1320

if(ret == -1){

1716

perror_plus("seteuid");

1321

perror("seteuid");

1717

1322

}

1718

1323

goto end;

1719

1324

}

1720

1325

}

1721

/* Sleep checking until interface is running.

1722

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

1326

/* sleep checking until interface is running */

1723

1327

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

1724

1328

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

1725

1329

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1330

perror("ioctl SIOCGIFFLAGS");

1727

1331

} else if(network.ifr_flags & IFF_RUNNING){

1728

1332

break;

1729

1333

}

1730

1334

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

1335

ret = nanosleep(&sleeptime, NULL);

1732

1336

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

1733

perror_plus("nanosleep");

1337

perror("nanosleep");

1734

1338

}

1735

1339

}

1736

1340

if(not take_down_interface){

1737

1341

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

1738

1342

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

1739

1343

if(ret == -1){

1740

perror_plus("close");

1344

perror("close");

1741

1345

}

1742

1346

}

1743

1347

#ifdef __linux__

1745

1349

/* Restores kernel loglevel to default */

1746

1350

ret = klogctl(7, NULL, 0);

1747

1351

if(ret == -1){

1748

perror_plus("klogctl");

1352

perror("klogctl");

1749

1353

}

1750

1354

}

1751

1355

#endif /* __linux__ */

1755

1359

/* Lower privileges */

1756

1360

ret = seteuid(uid);

1757

1361

if(ret == -1){

1758

perror_plus("seteuid");

1362

perror("seteuid");

1759

1363

}

1760

1364

} else {

1761

1365

/* Lower privileges permanently */

1762

1366

ret = setuid(uid);

1763

1367

if(ret == -1){

1764

perror_plus("setuid");

1368

perror("setuid");

1765

1369

}

1766

1370

}

1767

1371

}

1773

1377

ret = init_gnutls_global(pubkey, seckey);

1774

1378

if(ret == -1){

1775

1379

fprintf(stderr, "init_gnutls_global failed\n");

1776

exitcode = EX_UNAVAILABLE;

1380

exitcode = EXIT_FAILURE;

1777

1381

goto end;

1778

1382

} else {

1779

1383

gnutls_initialized = true;

1783

1387

goto end;

1784

1388

}

1785

1389

1390

tempdir_created = true;

1786

1391

if(mkdtemp(tempdir) == NULL){

1787

perror_plus("mkdtemp");

1392

tempdir_created = false;

1393

perror("mkdtemp");

1788

1394

goto end;

1789

1395

}

1790

tempdir_created = true;

1791

1396

1792

1397

if(quit_now){

1793

1398

goto end;

1795

1400

1796

1401

if(not init_gpgme(pubkey, seckey, tempdir)){

1797

1402

fprintf(stderr, "init_gpgme failed\n");

1798

exitcode = EX_UNAVAILABLE;

1403

exitcode = EXIT_FAILURE;

1799

1404

goto end;

1800

1405

} else {

1801

1406

gpgme_initialized = true;

1811

1416

char *address = strrchr(connect_to, ':');

1812

1417

if(address == NULL){

1813

1418

fprintf(stderr, "No colon in address\n");

1814

exitcode = EX_USAGE;

1419

exitcode = EXIT_FAILURE;

1815

1420

goto end;

1816

1421

}

1817

1422

1825

1430

if(errno != 0 or tmp == address+1 or *tmp != '\0'

1826

1431

or tmpmax != (uint16_t)tmpmax){

1827

1432

fprintf(stderr, "Bad port number\n");

1828

exitcode = EX_USAGE;

1433

exitcode = EXIT_FAILURE;

1829

1434

goto end;

1830

1435

}

1831

1436

1835

1440

1836

1441

port = (uint16_t)tmpmax;

1837

1442

*address = '\0';

1443

address = connect_to;

1838

1444

/* Colon in address indicates IPv6 */

1839

1445

int af;

1840

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

1446

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

1841

1447

af = AF_INET6;

1842

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

1843

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

1844

{

1845

connect_to++;

1846

address[-1] = '\0';

1847

}

1848

1448

} else {

1849

1449

af = AF_INET;

1850

1450

}

1851

address = connect_to;

1852

1451

1853

1452

if(quit_now){

1854

1453

goto end;

1855

1454

}

1856

1455

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){

1456

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

1457

if(ret < 0){

1458

exitcode = EXIT_FAILURE;

1459

} else {

1870

1460

exitcode = EXIT_SUCCESS;

1871

1461

}

1872

1873

1462

goto end;

1874

1463

}

1875

1464

1899

1488

if(mc.server == NULL){

1900

1489

fprintf(stderr, "Failed to create Avahi server: %s\n",

1901

1490

avahi_strerror(error));

1902

exitcode = EX_UNAVAILABLE;

1491

exitcode = EXIT_FAILURE;

1903

1492

goto end;

1904

1493

}

1905

1494

1914

1503

if(sb == NULL){

1915

1504

fprintf(stderr, "Failed to create service browser: %s\n",

1916

1505

avahi_strerror(avahi_server_errno(mc.server)));

1917

exitcode = EX_UNAVAILABLE;

1506

exitcode = EXIT_FAILURE;

1918

1507

goto end;

1919

1508

}

1920

1509

1927

1516

if(debug){

1928

1517

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

1929

1518

}

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

}

1519

1520

avahi_simple_poll_loop(mc.simple_poll);

1937

1521

1938

1522

end:

1939

1523

1960

1544

if(gpgme_initialized){

1961

1545

gpgme_release(mc.ctx);

1962

1546

}

1963

1964

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

1965

has seen */

1966

if(mc.current_server != NULL){

1967

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

1968

while(mc.current_server != NULL){

1969

server *next = mc.current_server->next;

1970

free(mc.current_server);

1971

mc.current_server = next;

1972

}

1973

}

1974

1547

1975

1548

/* Take down the network interface */

1976

1549

if(take_down_interface){

1978

1551

errno = 0;

1979

1552

ret = seteuid(0);

1980

1553

if(ret == -1){

1981

perror_plus("seteuid");

1554

perror("seteuid");

1982

1555

}

1983

1556

if(geteuid() == 0){

1984

1557

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

1985

1558

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1559

perror("ioctl SIOCGIFFLAGS");

1987

1560

} else if(network.ifr_flags & IFF_UP) {

1988

1561

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

1989

1562

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

1990

1563

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1564

perror("ioctl SIOCSIFFLAGS");

1992

1565

}

1993

1566

}

1994

1567

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

1995

1568

if(ret == -1){

1996

perror_plus("close");

1569

perror("close");

1997

1570

}

1998

1571

/* Lower privileges permanently */

1999

1572

errno = 0;

2000

1573

ret = setuid(uid);

2001

1574

if(ret == -1){

2002

perror_plus("setuid");

1575

perror("setuid");

2003

1576

}

2004

1577

}

2005

1578

}

2006

1579

2007

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

1580

/* Removes the temp directory used by GPGME */

2008

1581

if(tempdir_created){

2009

struct dirent **direntries = NULL;

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

direntry = direntries[i];

1582

DIR *d;

1583

struct dirent *direntry;

1584

d = opendir(tempdir);

1585

if(d == NULL){

1586

if(errno != ENOENT){

1587

perror("opendir");

1588

}

1589

} else {

1590

while(true){

1591

direntry = readdir(d);

1592

if(direntry == NULL){

1593

break;

1594

}

1595

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

1596

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

1597

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

1598

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

1599

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

1600

continue;

1601

}

2016

1602

char *fullname = NULL;

2017

1603

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

2018

1604

direntry->d_name);

2019

1605

if(ret < 0){

2020

perror_plus("asprintf");

1606

perror("asprintf");

2021

1607

continue;

2022

1608

}

2023

1609

ret = remove(fullname);

2027

1613

}

2028

1614

free(fullname);

2029

1615

}

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");

1616

closedir(d);

2036

1617

}

2037

1618

ret = rmdir(tempdir);

2038

1619

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

2039

perror_plus("rmdir");

1620

perror("rmdir");

2040

1621

}

2041

1622

}

2042

1623

2047

1628

&old_sigterm_action,

2048

1629

NULL));

2049

1630

if(ret == -1){

2050

perror_plus("sigaction");

1631

perror("sigaction");

2051

1632

}

2052

1633

do {

2053

1634

ret = raise(signal_received);

2054

1635

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

2055

1636

if(ret != 0){

2056

perror_plus("raise");

1637

perror("raise");

2057

1638

abort();

2058

1639

}

2059

1640

TEMP_FAILURE_RETRY(pause());