/mandos/release : revision 237.2.152

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 */

88

85

89

86

#ifdef __linux__

90

87

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

128

125

static const char mandos_protocol_version[] = "1";

129

126

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

130

127

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

128

145

129

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

146

130

typedef struct {

151

135

gnutls_dh_params_t dh_params;

152

136

const char *priority;

153

137

gpgme_ctx_t ctx;

154

server *current_server;

155

138

} mandos_context;

156

139

157

140

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

158

141

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

159

142

.dh_bits = 1024, .priority = "SECURE256"

160

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

161

.current_server = NULL };

143

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

162

144

163

145

sig_atomic_t quit_now = 0;

164

146

int signal_received = 0;

165

147

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

148

/*

174

149

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

175

150

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

187

162

return buffer_capacity;

188

163

}

189

164

190

int add_server(const char *ip, uint16_t port,

191

AvahiIfIndex if_index,

192

int af){

193

int ret;

194

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

195

if(new_server == NULL){

196

perror_plus("malloc");

197

return -1;

198

}

199

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

200

.port = port,

201

.if_index = if_index,

202

.af = af };

203

if(new_server->ip == NULL){

204

perror_plus("strdup");

205

return -1;

206

}

207

/* unique case of first server */

208

if (mc.current_server == NULL){

209

new_server->next = new_server;

210

new_server->prev = new_server;

211

mc.current_server = new_server;

212

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

213

} else {

214

new_server->next = mc.current_server;

215

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

216

new_server->prev->next = new_server;

217

mc.current_server->prev = new_server;

218

}

219

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

220

if(ret == -1){

221

perror_plus("clock_gettime");

222

return -1;

223

}

224

return 0;

225

}

226

227

165

/*

228

166

* Initialize GPGME.

229

167

*/

243

181

244

182

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

245

183

if(fd == -1){

246

perror_plus("open");

184

perror("open");

247

185

return false;

248

186

}

249

187

263

201

264

202

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

265

203

if(ret == -1){

266

perror_plus("close");

204

perror("close");

267

205

}

268

206

gpgme_data_release(pgp_data);

269

207

return true;

394

332

395

333

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

396

334

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

397

perror_plus("gpgme_data_seek");

335

perror("gpgme_data_seek");

398

336

plaintext_length = -1;

399

337

goto decrypt_end;

400

338

}

405

343

(size_t)plaintext_length,

406

344

plaintext_capacity);

407

345

if(plaintext_capacity == 0){

408

perror_plus("incbuffer");

346

perror("incbuffer");

409

347

plaintext_length = -1;

410

348

goto decrypt_end;

411

349

}

418

356

break;

419

357

}

420

358

if(ret < 0){

421

perror_plus("gpgme_data_read");

359

perror("gpgme_data_read");

422

360

plaintext_length = -1;

423

361

goto decrypt_end;

424

362

}

481

419

}

482

420

483

421

/* OpenPGP credentials */

484

ret = gnutls_certificate_allocate_credentials(&mc.cred);

422

gnutls_certificate_allocate_credentials(&mc.cred);

485

423

if(ret != GNUTLS_E_SUCCESS){

486

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

424

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

425

from

426

-Wunreachable-code

427

*/

487

428

safer_gnutls_strerror(ret));

488

429

gnutls_global_deinit();

489

430

return -1;

611

552

gnutls_session_t session;

612

553

int pf; /* Protocol family */

613

554

614

errno = 0;

615

616

555

if(quit_now){

617

errno = EINTR;

618

556

return -1;

619

557

}

620

558

627

565

break;

628

566

default:

629

567

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

630

errno = EINVAL;

631

568

return -1;

632

569

}

633

570

643

580

644

581

tcp_sd = socket(pf, SOCK_STREAM, 0);

645

582

if(tcp_sd < 0){

646

int e = errno;

647

perror_plus("socket");

648

errno = e;

583

perror("socket");

649

584

goto mandos_end;

650

585

}

651

586

652

587

if(quit_now){

653

errno = EINTR;

654

588

goto mandos_end;

655

589

}

656

590

663

597

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

664

598

}

665

599

if(ret < 0 ){

666

int e = errno;

667

perror_plus("inet_pton");

668

errno = e;

600

perror("inet_pton");

669

601

goto mandos_end;

670

602

}

671

603

if(ret == 0){

672

int e = errno;

673

604

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

674

errno = e;

675

605

goto mandos_end;

676

606

}

677

607

if(af == AF_INET6){

685

615

if(if_index == AVAHI_IF_UNSPEC){

686

616

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

687

617

" without a network interface\n");

688

errno = EINVAL;

689

618

goto mandos_end;

690

619

}

691

620

/* Set the network interface number as scope */

698

627

}

699

628

700

629

if(quit_now){

701

errno = EINTR;

702

630

goto mandos_end;

703

631

}

704

632

706

634

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

707

635

char interface[IF_NAMESIZE];

708

636

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

709

perror_plus("if_indextoname");

637

perror("if_indextoname");

710

638

} else {

711

639

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

712

640

ip, interface, port);

726

654

sizeof(addrstr));

727

655

}

728

656

if(pcret == NULL){

729

perror_plus("inet_ntop");

657

perror("inet_ntop");

730

658

} else {

731

659

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

732

660

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

735

663

}

736

664

737

665

if(quit_now){

738

errno = EINTR;

739

666

goto mandos_end;

740

667

}

741

668

745

672

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

746

673

}

747

674

if(ret < 0){

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

675

perror("connect");

753

676

goto mandos_end;

754

677

}

755

678

756

679

if(quit_now){

757

errno = EINTR;

758

680

goto mandos_end;

759

681

}

760

682

765

687

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

766

688

out_size - written));

767

689

if(ret == -1){

768

int e = errno;

769

perror_plus("write");

770

errno = e;

690

perror("write");

771

691

goto mandos_end;

772

692

}

773

693

written += (size_t)ret;

783

703

}

784

704

785

705

if(quit_now){

786

errno = EINTR;

787

706

goto mandos_end;

788

707

}

789

708

}

793

712

}

794

713

795

714

if(quit_now){

796

errno = EINTR;

797

715

goto mandos_end;

798

716

}

799

717

800

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

801

718

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

802

719

803

720

if(quit_now){

804

errno = EINTR;

805

721

goto mandos_end;

806

722

}

807

723

808

724

do {

809

725

ret = gnutls_handshake(session);

810

726

if(quit_now){

811

errno = EINTR;

812

727

goto mandos_end;

813

728

}

814

729

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

818

733

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

819

734

gnutls_perror(ret);

820

735

}

821

errno = EPROTO;

822

736

goto mandos_end;

823

737

}

824

738

832

746

while(true){

833

747

834

748

if(quit_now){

835

errno = EINTR;

836

749

goto mandos_end;

837

750

}

838

751

839

752

buffer_capacity = incbuffer(&buffer, buffer_length,

840

753

buffer_capacity);

841

754

if(buffer_capacity == 0){

842

int e = errno;

843

perror_plus("incbuffer");

844

errno = e;

755

perror("incbuffer");

845

756

goto mandos_end;

846

757

}

847

758

848

759

if(quit_now){

849

errno = EINTR;

850

760

goto mandos_end;

851

761

}

852

762

865

775

ret = gnutls_handshake(session);

866

776

867

777

if(quit_now){

868

errno = EINTR;

869

778

goto mandos_end;

870

779

}

871

780

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

872

781

if(ret < 0){

873

782

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

874

783

gnutls_perror(ret);

875

errno = EPROTO;

876

784

goto mandos_end;

877

785

}

878

786

break;

880

788

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

881

789

" encrypted session with Mandos server\n");

882

790

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

errno = EIO;

884

791

goto mandos_end;

885

792

}

886

793

} else {

893

800

}

894

801

895

802

if(quit_now){

896

errno = EINTR;

897

803

goto mandos_end;

898

804

}

899

805

900

806

do {

901

807

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

902

808

if(quit_now){

903

errno = EINTR;

904

809

goto mandos_end;

905

810

}

906

811

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

915

820

written = 0;

916

821

while(written < (size_t) decrypted_buffer_size){

917

822

if(quit_now){

918

errno = EINTR;

919

823

goto mandos_end;

920

824

}

921

825

923

827

(size_t)decrypted_buffer_size - written,

924

828

stdout);

925

829

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

926

int e = errno;

927

830

if(debug){

928

831

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

929

832

strerror(errno));

930

833

}

931

errno = e;

932

834

goto mandos_end;

933

835

}

934

836

written += (size_t)ret;

940

842

/* Shutdown procedure */

941

843

942

844

mandos_end:

943

{

944

int e = errno;

945

free(decrypted_buffer);

946

free(buffer);

947

if(tcp_sd >= 0){

948

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

949

}

950

if(ret == -1){

951

if(e == 0){

952

e = errno;

953

}

954

perror_plus("close");

955

}

956

gnutls_deinit(session);

957

errno = e;

958

if(quit_now){

959

errno = EINTR;

960

retval = -1;

961

}

845

free(decrypted_buffer);

846

free(buffer);

847

if(tcp_sd >= 0){

848

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

849

}

850

if(ret == -1){

851

perror("close");

852

}

853

gnutls_deinit(session);

854

if(quit_now){

855

retval = -1;

962

856

}

963

857

return retval;

964

858

}

1007

901

avahi_proto_to_af(proto));

1008

902

if(ret == 0){

1009

903

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

1013

904

}

1014

905

}

1015

906

}

1069

960

}

1070

961

}

1071

962

1072

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

963

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

1073

964

static void handle_sigterm(int sig){

1074

965

if(quit_now){

1075

966

return;

1077

968

quit_now = 1;

1078

969

signal_received = sig;

1079

970

int old_errno = errno;

1080

/* set main loop to exit */

1081

971

if(mc.simple_poll != NULL){

1082

972

avahi_simple_poll_quit(mc.simple_poll);

1083

973

}

1084

974

errno = old_errno;

1085

975

}

1086

976

1087

/*

1088

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

1089

* corresponds to an acceptable network device.

1090

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

1091

*/

1092

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1188

}

1189

return 1;

1190

}

1191

1192

int notdotentries(const struct dirent *direntry){

1193

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

1194

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

1195

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

1196

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

1197

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

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1204

int ret;

1205

struct timespec now;

1206

struct timespec waited_time;

1207

intmax_t block_time;

1208

1209

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

fprintf(stderr,

1213

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

1214

}

1215

ret = avahi_simple_poll_iterate(s, -1);

1216

} else {

1217

if (debug){

1218

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

1219

" or wait\n");

1220

}

1221

/* the current time */

1222

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1223

if(ret == -1){

1224

perror_plus("clock_gettime");

1225

return -1;

1226

}

1227

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

1228

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

1229

waited_time.tv_sec = (now.tv_sec

1230

- mc.current_server->last_seen.tv_sec);

1231

waited_time.tv_nsec = (now.tv_nsec

1232

- mc.current_server->last_seen.tv_nsec);

1233

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

1234

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

1235

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

1236

block_time = ((retry_interval

1237

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

1238

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

1239

1240

if (debug){

1241

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

1242

}

1243

1244

if(block_time <= 0){

1245

ret = start_mandos_communication(mc.current_server->ip,

1246

mc.current_server->port,

1247

mc.current_server->if_index,

1248

mc.current_server->af);

1249

if(ret == 0){

1250

avahi_simple_poll_quit(mc.simple_poll);

1251

return 0;

1252

}

1253

ret = clock_gettime(CLOCK_MONOTONIC,

1254

&mc.current_server->last_seen);

1255

if(ret == -1){

1256

perror_plus("clock_gettime");

1257

return -1;

1258

}

1259

mc.current_server = mc.current_server->next;

1260

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

1261

servers, but don't block */

1262

}

1263

1264

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

1265

}

1266

if(ret != 0){

1267

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

1268

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

1269

}

1270

}

1271

}

1272

}

1273

1274

977

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

1275

978

AvahiSServiceBrowser *sb = NULL;

1276

979

int error;

1278

981

intmax_t tmpmax;

1279

982

char *tmp;

1280

983

int exitcode = EXIT_SUCCESS;

1281

const char *interface = "";

984

const char *interface = "eth0";

1282

985

struct ifreq network;

1283

986

int sd = -1;

1284

987

bool take_down_interface = false;

1285

988

uid_t uid;

1286

989

gid_t gid;

990

char *connect_to = NULL;

1287

991

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

1288

992

bool tempdir_created = false;

1289

993

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1293

997

bool gnutls_initialized = false;

1294

998

bool gpgme_initialized = false;

1295

999

float delay = 2.5f;

1296

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

1297

retrying the same server again */

1298

1000

1299

1001

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1300

1002

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1306

1008

errno = 0;

1307

1009

ret = setgid(gid);

1308

1010

if(ret == -1){

1309

perror_plus("setgid");

1011

perror("setgid");

1310

1012

}

1311

1013

1312

1014

/* Lower user privileges (temporarily) */

1313

1015

errno = 0;

1314

1016

ret = seteuid(uid);

1315

1017

if(ret == -1){

1316

perror_plus("seteuid");

1018

perror("seteuid");

1317

1019

}

1318

1020

1319

1021

if(quit_now){

1354

1056

.arg = "SECONDS",

1355

1057

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

1356

1058

.group = 2 },

1357

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

1358

.arg = "SECONDS",

1359

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

1360

.group = 2 },

1361

/*

1362

* These reproduce what we would get without ARGP_NO_HELP

1363

*/

1364

{ .name = "help", .key = '?',

1365

.doc = "Give this help list", .group = -1 },

1366

{ .name = "usage", .key = -3,

1367

.doc = "Give a short usage message", .group = -1 },

1368

{ .name = "version", .key = 'V',

1369

.doc = "Print program version", .group = -1 },

1370

1059

{ .name = NULL }

1371

1060

};

1372

1061

1373

1062

error_t parse_opt(int key, char *arg,

1374

1063

struct argp_state *state){

1375

errno = 0;

1376

1064

switch(key){

1377

1065

case 128: /* --debug */

1378

1066

debug = true;

1394

1082

tmpmax = strtoimax(arg, &tmp, 10);

1395

1083

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

1396

1084

or tmpmax != (typeof(mc.dh_bits))tmpmax){

1397

argp_error(state, "Bad number of DH bits");

1085

fprintf(stderr, "Bad number of DH bits\n");

1086

exit(EXIT_FAILURE);

1398

1087

}

1399

1088

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

1400

1089

break;

1405

1094

errno = 0;

1406

1095

delay = strtof(arg, &tmp);

1407

1096

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

1408

argp_error(state, "Bad delay");

1409

}

1410

case 132: /* --retry */

1411

errno = 0;

1412

retry_interval = strtod(arg, &tmp);

1413

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

1414

or (retry_interval * 1000) > INT_MAX){

1415

argp_error(state, "Bad retry interval");

1097

fprintf(stderr, "Bad delay\n");

1098

exit(EXIT_FAILURE);

1416

1099

}

1417

1100

break;

1418

/*

1419

* These reproduce what we would get without ARGP_NO_HELP

1420

*/

1421

case '?': /* --help */

1422

argp_state_help(state, state->out_stream,

1423

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1424

& ~(unsigned int)ARGP_HELP_EXIT_OK);

1425

case -3: /* --usage */

1426

argp_state_help(state, state->out_stream,

1427

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1428

case 'V': /* --version */

1429

fprintf(state->out_stream, "%s\n", argp_program_version);

1430

exit(argp_err_exit_status);

1101

case ARGP_KEY_ARG:

1102

argp_usage(state);

1103

case ARGP_KEY_END:

1431

1104

break;

1432

1105

default:

1433

1106

return ARGP_ERR_UNKNOWN;

1434

1107

}

1435

return errno;

1108

return 0;

1436

1109

}

1437

1110

1438

1111

struct argp argp = { .options = options, .parser = parse_opt,

1439

1112

.args_doc = "",

1440

1113

.doc = "Mandos client -- Get and decrypt"

1441

1114

" passwords from a Mandos server" };

1442

ret = argp_parse(&argp, argc, argv,

1443

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1444

switch(ret){

1445

case 0:

1446

break;

1447

case ENOMEM:

1448

default:

1449

errno = ret;

1450

perror_plus("argp_parse");

1451

exitcode = EX_OSERR;

1452

goto end;

1453

case EINVAL:

1454

exitcode = EX_USAGE;

1455

goto end;

1456

}

1457

}

1458

1459

{

1460

/* Work around Debian bug #633582:

1461

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

1462

struct stat st;

1463

1464

/* Re-raise priviliges */

1465

errno = 0;

1466

ret = seteuid(0);

1467

if(ret == -1){

1468

perror_plus("seteuid");

1469

}

1470

1471

int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);

1472

if(seckey_fd == -1){

1473

perror_plus("open");

1474

} else {

1475

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

1476

if(ret == -1){

1477

perror_plus("fstat");

1478

} else {

1479

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

1480

ret = fchown(seckey_fd, uid, gid);

1481

if(ret == -1){

1482

perror_plus("fchown");

1483

}

1484

}

1485

}

1486

TEMP_FAILURE_RETRY(close(seckey_fd));

1487

}

1488

1489

int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);

1490

if(pubkey_fd == -1){

1491

perror_plus("open");

1492

} else {

1493

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

1494

if(ret == -1){

1495

perror_plus("fstat");

1496

} else {

1497

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

1498

ret = fchown(pubkey_fd, uid, gid);

1499

if(ret == -1){

1500

perror_plus("fchown");

1501

}

1502

}

1503

}

1504

TEMP_FAILURE_RETRY(close(pubkey_fd));

1505

}

1506

1507

/* Lower privileges */

1508

errno = 0;

1509

ret = seteuid(uid);

1510

if(ret == -1){

1511

perror_plus("seteuid");

1115

ret = argp_parse(&argp, argc, argv, 0, 0, NULL);

1116

if(ret == ARGP_ERR_UNKNOWN){

1117

fprintf(stderr, "Unknown error while parsing arguments\n");

1118

exitcode = EXIT_FAILURE;

1119

goto end;

1512

1120

}

1513

1121

}

1514

1122

1515

1123

if(not debug){

1516

1124

avahi_set_log_function(empty_log);

1517

1125

}

1518

1519

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

1520

struct dirent **direntries;

1521

ret = scandir(sys_class_net, &direntries, good_interface,

1522

alphasort);

1523

if(ret >= 1){

1524

/* Pick the first good interface */

1525

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

1526

if(debug){

1527

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

1528

}

1529

if(interface == NULL){

1530

perror_plus("malloc");

1531

free(direntries);

1532

exitcode = EXIT_FAILURE;

1533

goto end;

1534

}

1535

free(direntries);

1536

} else {

1537

free(direntries);

1538

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

1539

exitcode = EXIT_FAILURE;

1540

goto end;

1541

}

1542

}

1543

1126

1544

1127

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

1545

1128

from the signal handler */

1548

1131

mc.simple_poll = avahi_simple_poll_new();

1549

1132

if(mc.simple_poll == NULL){

1550

1133

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

1551

exitcode = EX_UNAVAILABLE;

1134

exitcode = EXIT_FAILURE;

1552

1135

goto end;

1553

1136

}

1554

1137

1555

1138

sigemptyset(&sigterm_action.sa_mask);

1556

1139

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

1557

1140

if(ret == -1){

1558

perror_plus("sigaddset");

1559

exitcode = EX_OSERR;

1141

perror("sigaddset");

1142

exitcode = EXIT_FAILURE;

1560

1143

goto end;

1561

1144

}

1562

1145

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

1563

1146

if(ret == -1){

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1147

perror("sigaddset");

1148

exitcode = EXIT_FAILURE;

1566

1149

goto end;

1567

1150

}

1568

1151

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

1569

1152

if(ret == -1){

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1153

perror("sigaddset");

1154

exitcode = EXIT_FAILURE;

1572

1155

goto end;

1573

1156

}

1574

1157

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

1577

1160

*/

1578

1161

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

1579

1162

if(ret == -1){

1580

perror_plus("sigaction");

1581

return EX_OSERR;

1163

perror("sigaction");

1164

return EXIT_FAILURE;

1582

1165

}

1583

1166

if(old_sigterm_action.sa_handler != SIG_IGN){

1584

1167

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

1585

1168

if(ret == -1){

1586

perror_plus("sigaction");

1587

exitcode = EX_OSERR;

1169

perror("sigaction");

1170

exitcode = EXIT_FAILURE;

1588

1171

goto end;

1589

1172

}

1590

1173

}

1591

1174

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

1592

1175

if(ret == -1){

1593

perror_plus("sigaction");

1594

return EX_OSERR;

1176

perror("sigaction");

1177

return EXIT_FAILURE;

1595

1178

}

1596

1179

if(old_sigterm_action.sa_handler != SIG_IGN){

1597

1180

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

1598

1181

if(ret == -1){

1599

perror_plus("sigaction");

1600

exitcode = EX_OSERR;

1182

perror("sigaction");

1183

exitcode = EXIT_FAILURE;

1601

1184

goto end;

1602

1185

}

1603

1186

}

1604

1187

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

1605

1188

if(ret == -1){

1606

perror_plus("sigaction");

1607

return EX_OSERR;

1189

perror("sigaction");

1190

return EXIT_FAILURE;

1608

1191

}

1609

1192

if(old_sigterm_action.sa_handler != SIG_IGN){

1610

1193

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

1611

1194

if(ret == -1){

1612

perror_plus("sigaction");

1613

exitcode = EX_OSERR;

1195

perror("sigaction");

1196

exitcode = EXIT_FAILURE;

1614

1197

goto end;

1615

1198

}

1616

1199

}

1617

1200

1618

1201

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

1619

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

1202

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

1620

1203

if_index = (AvahiIfIndex) if_nametoindex(interface);

1621

1204

if(if_index == 0){

1622

1205

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

1623

exitcode = EX_UNAVAILABLE;

1206

exitcode = EXIT_FAILURE;

1624

1207

goto end;

1625

1208

}

1626

1209

1632

1215

errno = 0;

1633

1216

ret = seteuid(0);

1634

1217

if(ret == -1){

1635

perror_plus("seteuid");

1218

perror("seteuid");

1636

1219

}

1637

1220

1638

1221

#ifdef __linux__

1639

1222

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1640

messages about the network interface to mess up the prompt */

1223

messages to mess up the prompt */

1641

1224

ret = klogctl(8, NULL, 5);

1642

1225

bool restore_loglevel = true;

1643

1226

if(ret == -1){

1644

1227

restore_loglevel = false;

1645

perror_plus("klogctl");

1228

perror("klogctl");

1646

1229

}

1647

1230

#endif /* __linux__ */

1648

1231

1649

1232

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

1233

if(sd < 0){

1651

perror_plus("socket");

1652

exitcode = EX_OSERR;

1234

perror("socket");

1235

exitcode = EXIT_FAILURE;

1653

1236

#ifdef __linux__

1654

1237

if(restore_loglevel){

1655

1238

ret = klogctl(7, NULL, 0);

1656

1239

if(ret == -1){

1657

perror_plus("klogctl");

1240

perror("klogctl");

1658

1241

}

1659

1242

}

1660

1243

#endif /* __linux__ */

1662

1245

errno = 0;

1663

1246

ret = seteuid(uid);

1664

1247

if(ret == -1){

1665

perror_plus("seteuid");

1248

perror("seteuid");

1666

1249

}

1667

1250

goto end;

1668

1251

}

1669

1252

strcpy(network.ifr_name, interface);

1670

1253

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

1671

1254

if(ret == -1){

1672

perror_plus("ioctl SIOCGIFFLAGS");

1255

perror("ioctl SIOCGIFFLAGS");

1673

1256

#ifdef __linux__

1674

1257

if(restore_loglevel){

1675

1258

ret = klogctl(7, NULL, 0);

1676

1259

if(ret == -1){

1677

perror_plus("klogctl");

1260

perror("klogctl");

1678

1261

}

1679

1262

}

1680

1263

#endif /* __linux__ */

1681

exitcode = EX_OSERR;

1264

exitcode = EXIT_FAILURE;

1682

1265

/* Lower privileges */

1683

1266

errno = 0;

1684

1267

ret = seteuid(uid);

1685

1268

if(ret == -1){

1686

perror_plus("seteuid");

1269

perror("seteuid");

1687

1270

}

1688

1271

goto end;

1689

1272

}

1693

1276

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

1694

1277

if(ret == -1){

1695

1278

take_down_interface = false;

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1697

exitcode = EX_OSERR;

1279

perror("ioctl SIOCSIFFLAGS");

1280

exitcode = EXIT_FAILURE;

1698

1281

#ifdef __linux__

1699

1282

if(restore_loglevel){

1700

1283

ret = klogctl(7, NULL, 0);

1701

1284

if(ret == -1){

1702

perror_plus("klogctl");

1285

perror("klogctl");

1703

1286

}

1704

1287

}

1705

1288

#endif /* __linux__ */

1707

1290

errno = 0;

1708

1291

ret = seteuid(uid);

1709

1292

if(ret == -1){

1710

perror_plus("seteuid");

1293

perror("seteuid");

1711

1294

}

1712

1295

goto end;

1713

1296

}

1714

1297

}

1715

/* Sleep checking until interface is running.

1716

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

1298

/* sleep checking until interface is running */

1717

1299

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

1718

1300

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

1719

1301

if(ret == -1){

1720

perror_plus("ioctl SIOCGIFFLAGS");

1302

perror("ioctl SIOCGIFFLAGS");

1721

1303

} else if(network.ifr_flags & IFF_RUNNING){

1722

1304

break;

1723

1305

}

1724

1306

struct timespec sleeptime = { .tv_nsec = 250000000 };

1725

1307

ret = nanosleep(&sleeptime, NULL);

1726

1308

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

1727

perror_plus("nanosleep");

1309

perror("nanosleep");

1728

1310

}

1729

1311

}

1730

1312

if(not take_down_interface){

1731

1313

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

1732

1314

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

1733

1315

if(ret == -1){

1734

perror_plus("close");

1316

perror("close");

1735

1317

}

1736

1318

}

1737

1319

#ifdef __linux__

1739

1321

/* Restores kernel loglevel to default */

1740

1322

ret = klogctl(7, NULL, 0);

1741

1323

if(ret == -1){

1742

perror_plus("klogctl");

1324

perror("klogctl");

1743

1325

}

1744

1326

}

1745

1327

#endif /* __linux__ */

1749

1331

/* Lower privileges */

1750

1332

ret = seteuid(uid);

1751

1333

if(ret == -1){

1752

perror_plus("seteuid");

1334

perror("seteuid");

1753

1335

}

1754

1336

} else {

1755

1337

/* Lower privileges permanently */

1756

1338

ret = setuid(uid);

1757

1339

if(ret == -1){

1758

perror_plus("setuid");

1340

perror("setuid");

1759

1341

}

1760

1342

}

1761

1343

}

1767

1349

ret = init_gnutls_global(pubkey, seckey);

1768

1350

if(ret == -1){

1769

1351

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

1770

exitcode = EX_UNAVAILABLE;

1352

exitcode = EXIT_FAILURE;

1771

1353

goto end;

1772

1354

} else {

1773

1355

gnutls_initialized = true;

1777

1359

goto end;

1778

1360

}

1779

1361

1362

tempdir_created = true;

1780

1363

if(mkdtemp(tempdir) == NULL){

1781

perror_plus("mkdtemp");

1364

tempdir_created = false;

1365

perror("mkdtemp");

1782

1366

goto end;

1783

1367

}

1784

tempdir_created = true;

1785

1368

1786

1369

if(quit_now){

1787

1370

goto end;

1789

1372

1790

1373

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

1791

1374

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

1792

exitcode = EX_UNAVAILABLE;

1375

exitcode = EXIT_FAILURE;

1793

1376

goto end;

1794

1377

} else {

1795

1378

gpgme_initialized = true;

1805

1388

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

1806

1389

if(address == NULL){

1807

1390

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

1808

exitcode = EX_USAGE;

1391

exitcode = EXIT_FAILURE;

1809

1392

goto end;

1810

1393

}

1811

1394

1819

1402

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

1820

1403

or tmpmax != (uint16_t)tmpmax){

1821

1404

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

1822

exitcode = EX_USAGE;

1405

exitcode = EXIT_FAILURE;

1823

1406

goto end;

1824

1407

}

1825

1408

1841

1424

if(quit_now){

1842

1425

goto end;

1843

1426

}

1844

1845

while(not quit_now){

1846

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

1847

if(quit_now or ret == 0){

1848

break;

1849

}

1850

sleep((int)retry_interval or 1);

1851

};

1852

1853

if (not quit_now){

1427

1428

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

1429

if(ret < 0){

1430

exitcode = EXIT_FAILURE;

1431

} else {

1854

1432

exitcode = EXIT_SUCCESS;

1855

1433

}

1856

1857

1434

goto end;

1858

1435

}

1859

1436

1883

1460

if(mc.server == NULL){

1884

1461

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

1885

1462

avahi_strerror(error));

1886

exitcode = EX_UNAVAILABLE;

1463

exitcode = EXIT_FAILURE;

1887

1464

goto end;

1888

1465

}

1889

1466

1898

1475

if(sb == NULL){

1899

1476

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

1900

1477

avahi_strerror(avahi_server_errno(mc.server)));

1901

exitcode = EX_UNAVAILABLE;

1478

exitcode = EXIT_FAILURE;

1902

1479

goto end;

1903

1480

}

1904

1481

1911

1488

if(debug){

1912

1489

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

1913

1490

}

1914

1915

ret = avahi_loop_with_timeout(mc.simple_poll,

1916

(int)(retry_interval * 1000));

1917

if(debug){

1918

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

1919

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

1920

}

1491

1492

avahi_simple_poll_loop(mc.simple_poll);

1921

1493

1922

1494

end:

1923

1495

1944

1516

if(gpgme_initialized){

1945

1517

gpgme_release(mc.ctx);

1946

1518

}

1947

1948

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

1949

has seen */

1950

if(mc.current_server != NULL){

1951

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

1952

while(mc.current_server != NULL){

1953

server *next = mc.current_server->next;

1954

free(mc.current_server);

1955

mc.current_server = next;

1956

}

1957

}

1958

1519

1959

1520

/* Take down the network interface */

1960

1521

if(take_down_interface){

1962

1523

errno = 0;

1963

1524

ret = seteuid(0);

1964

1525

if(ret == -1){

1965

perror_plus("seteuid");

1526

perror("seteuid");

1966

1527

}

1967

1528

if(geteuid() == 0){

1968

1529

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

1969

1530

if(ret == -1){

1970

perror_plus("ioctl SIOCGIFFLAGS");

1531

perror("ioctl SIOCGIFFLAGS");

1971

1532

} else if(network.ifr_flags & IFF_UP) {

1972

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

1533

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

1973

1534

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

1974

1535

if(ret == -1){

1975

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1536

perror("ioctl SIOCSIFFLAGS");

1976

1537

}

1977

1538

}

1978

1539

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

1979

1540

if(ret == -1){

1980

perror_plus("close");

1541

perror("close");

1981

1542

}

1982

1543

/* Lower privileges permanently */

1983

1544

errno = 0;

1984

1545

ret = setuid(uid);

1985

1546

if(ret == -1){

1986

perror_plus("setuid");

1547

perror("setuid");

1987

1548

}

1988

1549

}

1989

1550

}

1990

1551

1991

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

1552

/* Removes the temp directory used by GPGME */

1992

1553

if(tempdir_created){

1993

struct dirent **direntries = NULL;

1994

struct dirent *direntry = NULL;

1995

ret = scandir(tempdir, &direntries, notdotentries, alphasort);

1996

if (ret > 0){

1997

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

1998

direntry = direntries[i];

1554

DIR *d;

1555

struct dirent *direntry;

1556

d = opendir(tempdir);

1557

if(d == NULL){

1558

if(errno != ENOENT){

1559

perror("opendir");

1560

}

1561

} else {

1562

while(true){

1563

direntry = readdir(d);

1564

if(direntry == NULL){

1565

break;

1566

}

1567

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

1568

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

1569

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

1570

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

1571

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

1572

continue;

1573

}

1999

1574

char *fullname = NULL;

2000

1575

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

2001

1576

direntry->d_name);

2002

1577

if(ret < 0){

2003

perror_plus("asprintf");

1578

perror("asprintf");

2004

1579

continue;

2005

1580

}

2006

1581

ret = remove(fullname);

2010

1585

}

2011

1586

free(fullname);

2012

1587

}

2013

}

2014

2015

/* need to be cleaned even if ret == 0 because man page doesn't

2016

specify */

2017

free(direntries);

2018

if (ret == -1){

2019

perror_plus("scandir");

1588

closedir(d);

2020

1589

}

2021

1590

ret = rmdir(tempdir);

2022

1591

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

2023

perror_plus("rmdir");

1592

perror("rmdir");

2024

1593

}

2025

1594

}

2026

1595

2031

1600

&old_sigterm_action,

2032

1601

NULL));

2033

1602

if(ret == -1){

2034

perror_plus("sigaction");

1603

perror("sigaction");

2035

1604

}

2036

1605

do {

2037

1606

ret = raise(signal_received);

2038

1607

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

2039

1608

if(ret != 0){

2040

perror_plus("raise");

1609

perror("raise");

2041

1610

abort();

2042

1611

}

2043

1612

TEMP_FAILURE_RETRY(pause());