/mandos/trunk : revision 487

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, EXIT_FAILURE,

47

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

46

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

47

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

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

65

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

66

program_invocation_short_name */

67

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

67

68

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

68

69

SIOCSIFFLAGS, if_indextoname(),

69

70

if_nametoindex(), IF_NAMESIZE */

73

74

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

74

75

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

75

76

setgid(), pause() */

76

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

77

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

77

78

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

78

79

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

79

80

argp_state, struct argp,

82

83

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

83

84

sigaction(), SIGTERM, sig_atomic_t,

84

85

raise() */

86

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

87

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

85

88

86

89

#ifdef __linux__

87

90

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

125

128

static const char mandos_protocol_version[] = "1";

126

129

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

127

130

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

131

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

132

char *connect_to = NULL;

133

134

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

135

typedef struct server{

136

const char *ip;

137

uint16_t port;

138

AvahiIfIndex if_index;

139

int af;

140

struct timespec last_seen;

141

struct server *next;

142

struct server *prev;

143

} server;

128

144

129

145

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

130

146

typedef struct {

135

151

gnutls_dh_params_t dh_params;

136

152

const char *priority;

137

153

gpgme_ctx_t ctx;

154

server *current_server;

138

155

} mandos_context;

139

156

140

157

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

141

158

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

142

159

.dh_bits = 1024, .priority = "SECURE256"

143

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

160

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

161

.current_server = NULL };

144

162

145

163

sig_atomic_t quit_now = 0;

146

164

int signal_received = 0;

147

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

148

173

/*

149

174

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

150

175

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

162

187

return buffer_capacity;

163

188

}

164

189

190

int add_server(const char *ip, uint16_t port,

191

AvahiIfIndex if_index,

192

int af){

193

int ret;

194

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

195

if(new_server == NULL){

196

perror_plus("malloc");

197

return -1;

198

}

199

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

200

.port = port,

201

.if_index = if_index,

202

.af = af };

203

if(new_server->ip == NULL){

204

perror_plus("strdup");

205

return -1;

206

}

207

/* unique case of first server */

208

if (mc.current_server == NULL){

209

new_server->next = new_server;

210

new_server->prev = new_server;

211

mc.current_server = new_server;

212

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

213

} else {

214

new_server->next = mc.current_server;

215

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

216

new_server->prev->next = new_server;

217

mc.current_server->prev = new_server;

218

}

219

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

220

if(ret == -1){

221

perror_plus("clock_gettime");

222

return -1;

223

}

224

return 0;

225

}

226

165

227

/*

166

228

* Initialize GPGME.

167

229

*/

181

243

182

244

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

183

245

if(fd == -1){

184

perror("open");

246

perror_plus("open");

185

247

return false;

186

248

}

187

249

201

263

202

264

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

203

265

if(ret == -1){

204

perror("close");

266

perror_plus("close");

205

267

}

206

268

gpgme_data_release(pgp_data);

207

269

return true;

332

394

333

395

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

334

396

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

335

perror("gpgme_data_seek");

397

perror_plus("gpgme_data_seek");

336

398

plaintext_length = -1;

337

399

goto decrypt_end;

338

400

}

343

405

(size_t)plaintext_length,

344

406

plaintext_capacity);

345

407

if(plaintext_capacity == 0){

346

perror("incbuffer");

408

perror_plus("incbuffer");

347

409

plaintext_length = -1;

348

410

goto decrypt_end;

349

411

}

356

418

break;

357

419

}

358

420

if(ret < 0){

359

perror("gpgme_data_read");

421

perror_plus("gpgme_data_read");

360

422

plaintext_length = -1;

361

423

goto decrypt_end;

362

424

}

419

481

}

420

482

421

483

/* OpenPGP credentials */

422

gnutls_certificate_allocate_credentials(&mc.cred);

484

ret = gnutls_certificate_allocate_credentials(&mc.cred);

423

485

if(ret != GNUTLS_E_SUCCESS){

424

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

425

from

426

-Wunreachable-code

427

*/

486

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

428

487

safer_gnutls_strerror(ret));

429

488

gnutls_global_deinit();

430

489

return -1;

552

611

gnutls_session_t session;

553

612

int pf; /* Protocol family */

554

613

614

errno = 0;

615

555

616

if(quit_now){

617

errno = EINTR;

556

618

return -1;

557

619

}

558

620

565

627

break;

566

628

default:

567

629

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

630

errno = EINVAL;

568

631

return -1;

569

632

}

570

633

580

643

581

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

582

645

if(tcp_sd < 0){

583

perror("socket");

646

int e = errno;

647

perror_plus("socket");

648

errno = e;

584

649

goto mandos_end;

585

650

}

586

651

587

652

if(quit_now){

653

errno = EINTR;

588

654

goto mandos_end;

589

655

}

590

656

597

663

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

598

664

}

599

665

if(ret < 0 ){

600

perror("inet_pton");

666

int e = errno;

667

perror_plus("inet_pton");

668

errno = e;

601

669

goto mandos_end;

602

670

}

603

671

if(ret == 0){

672

int e = errno;

604

673

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

674

errno = e;

605

675

goto mandos_end;

606

676

}

607

677

if(af == AF_INET6){

615

685

if(if_index == AVAHI_IF_UNSPEC){

616

686

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

617

687

" without a network interface\n");

688

errno = EINVAL;

618

689

goto mandos_end;

619

690

}

620

691

/* Set the network interface number as scope */

627

698

}

628

699

629

700

if(quit_now){

701

errno = EINTR;

630

702

goto mandos_end;

631

703

}

632

704

634

706

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

635

707

char interface[IF_NAMESIZE];

636

708

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

637

perror("if_indextoname");

709

perror_plus("if_indextoname");

638

710

} else {

639

711

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

640

712

ip, interface, port);

654

726

sizeof(addrstr));

655

727

}

656

728

if(pcret == NULL){

657

perror("inet_ntop");

729

perror_plus("inet_ntop");

658

730

} else {

659

731

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

660

732

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

663

735

}

664

736

665

737

if(quit_now){

738

errno = EINTR;

666

739

goto mandos_end;

667

740

}

668

741

672

745

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

673

746

}

674

747

if(ret < 0){

675

perror("connect");

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

676

753

goto mandos_end;

677

754

}

678

755

679

756

if(quit_now){

757

errno = EINTR;

680

758

goto mandos_end;

681

759

}

682

760

687

765

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

688

766

out_size - written));

689

767

if(ret == -1){

690

perror("write");

768

int e = errno;

769

perror_plus("write");

770

errno = e;

691

771

goto mandos_end;

692

772

}

693

773

written += (size_t)ret;

703

783

}

704

784

705

785

if(quit_now){

786

errno = EINTR;

706

787

goto mandos_end;

707

788

}

708

789

}

712

793

}

713

794

714

795

if(quit_now){

796

errno = EINTR;

715

797

goto mandos_end;

716

798

}

717

799

800

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

718

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

719

802

720

803

if(quit_now){

804

errno = EINTR;

721

805

goto mandos_end;

722

806

}

723

807

724

808

do {

725

809

ret = gnutls_handshake(session);

726

810

if(quit_now){

811

errno = EINTR;

727

812

goto mandos_end;

728

813

}

729

814

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

733

818

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

734

819

gnutls_perror(ret);

735

820

}

821

errno = EPROTO;

736

822

goto mandos_end;

737

823

}

738

824

746

832

while(true){

747

833

748

834

if(quit_now){

835

errno = EINTR;

749

836

goto mandos_end;

750

837

}

751

838

752

839

buffer_capacity = incbuffer(&buffer, buffer_length,

753

840

buffer_capacity);

754

841

if(buffer_capacity == 0){

755

perror("incbuffer");

842

int e = errno;

843

perror_plus("incbuffer");

844

errno = e;

756

845

goto mandos_end;

757

846

}

758

847

759

848

if(quit_now){

849

errno = EINTR;

760

850

goto mandos_end;

761

851

}

762

852

775

865

ret = gnutls_handshake(session);

776

866

777

867

if(quit_now){

868

errno = EINTR;

778

869

goto mandos_end;

779

870

}

780

871

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

781

872

if(ret < 0){

782

873

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

783

874

gnutls_perror(ret);

875

errno = EPROTO;

784

876

goto mandos_end;

785

877

}

786

878

break;

788

880

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

789

881

" encrypted session with Mandos server\n");

790

882

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

errno = EIO;

791

884

goto mandos_end;

792

885

}

793

886

} else {

800

893

}

801

894

802

895

if(quit_now){

896

errno = EINTR;

803

897

goto mandos_end;

804

898

}

805

899

806

900

do {

807

901

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

808

902

if(quit_now){

903

errno = EINTR;

809

904

goto mandos_end;

810

905

}

811

906

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

820

915

written = 0;

821

916

while(written < (size_t) decrypted_buffer_size){

822

917

if(quit_now){

918

errno = EINTR;

823

919

goto mandos_end;

824

920

}

825

921

827

923

(size_t)decrypted_buffer_size - written,

828

924

stdout);

829

925

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

926

int e = errno;

830

927

if(debug){

831

928

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

832

929

strerror(errno));

833

930

}

931

errno = e;

834

932

goto mandos_end;

835

933

}

836

934

written += (size_t)ret;

842

940

/* Shutdown procedure */

843

941

844

942

mandos_end:

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;

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

}

856

962

}

857

963

return retval;

858

964

}

901

1007

avahi_proto_to_af(proto));

902

1008

if(ret == 0){

903

1009

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

904

1013

}

905

1014

}

906

1015

}

960

1069

}

961

1070

}

962

1071

963

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

1072

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

964

1073

static void handle_sigterm(int sig){

965

1074

if(quit_now){

966

1075

return;

968

1077

quit_now = 1;

969

1078

signal_received = sig;

970

1079

int old_errno = errno;

1080

/* set main loop to exit */

971

1081

if(mc.simple_poll != NULL){

972

1082

avahi_simple_poll_quit(mc.simple_poll);

973

1083

}

974

1084

errno = old_errno;

975

1085

}

976

1086

1087

/*

1088

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

1089

* corresponds to an acceptable network device.

1090

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

1091

*/

1092

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

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

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1188

}

1189

return 1;

1190

}

1191

1192

int notdotentries(const struct dirent *direntry){

1193

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

1194

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

1195

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

1196

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

1197

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

1198

return 0;

1199

}

1200

return 1;

1201

}

1202

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1204

int ret;

1205

struct timespec now;

1206

struct timespec waited_time;

1207

intmax_t block_time;

1208

1209

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

fprintf(stderr,

1213

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

1214

}

1215

ret = avahi_simple_poll_iterate(s, -1);

1216

} else {

1217

if (debug){

1218

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

1219

" or wait\n");

1220

}

1221

/* the current time */

1222

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1223

if(ret == -1){

1224

perror_plus("clock_gettime");

1225

return -1;

1226

}

1227

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

1228

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

1229

waited_time.tv_sec = (now.tv_sec

1230

- mc.current_server->last_seen.tv_sec);

1231

waited_time.tv_nsec = (now.tv_nsec

1232

- mc.current_server->last_seen.tv_nsec);

1233

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

1234

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

1235

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

1236

block_time = ((retry_interval

1237

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

1238

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

1239

1240

if (debug){

1241

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

1242

}

1243

1244

if(block_time <= 0){

1245

ret = start_mandos_communication(mc.current_server->ip,

1246

mc.current_server->port,

1247

mc.current_server->if_index,

1248

mc.current_server->af);

1249

if(ret == 0){

1250

avahi_simple_poll_quit(mc.simple_poll);

1251

return 0;

1252

}

1253

ret = clock_gettime(CLOCK_MONOTONIC,

1254

&mc.current_server->last_seen);

1255

if(ret == -1){

1256

perror_plus("clock_gettime");

1257

return -1;

1258

}

1259

mc.current_server = mc.current_server->next;

1260

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

1261

servers, but don't block */

1262

}

1263

1264

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

1265

}

1266

if(ret != 0){

1267

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

1268

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

1269

}

1270

}

1271

}

1272

}

1273

977

1274

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

978

1275

AvahiSServiceBrowser *sb = NULL;

979

1276

int error;

981

1278

intmax_t tmpmax;

982

1279

char *tmp;

983

1280

int exitcode = EXIT_SUCCESS;

984

const char *interface = "eth0";

1281

const char *interface = "";

985

1282

struct ifreq network;

986

1283

int sd = -1;

987

1284

bool take_down_interface = false;

988

1285

uid_t uid;

989

1286

gid_t gid;

990

char *connect_to = NULL;

991

1287

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

992

1288

bool tempdir_created = false;

993

1289

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

997

1293

bool gnutls_initialized = false;

998

1294

bool gpgme_initialized = false;

999

1295

float delay = 2.5f;

1296

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

1297

retrying the same server again */

1000

1298

1001

1299

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1002

1300

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1008

1306

errno = 0;

1009

1307

ret = setgid(gid);

1010

1308

if(ret == -1){

1011

perror("setgid");

1309

perror_plus("setgid");

1012

1310

}

1013

1311

1014

1312

/* Lower user privileges (temporarily) */

1015

1313

errno = 0;

1016

1314

ret = seteuid(uid);

1017

1315

if(ret == -1){

1018

perror("seteuid");

1316

perror_plus("seteuid");

1019

1317

}

1020

1318

1021

1319

if(quit_now){

1056

1354

.arg = "SECONDS",

1057

1355

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

1058

1356

.group = 2 },

1357

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

1358

.arg = "SECONDS",

1359

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

1360

.group = 2 },

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 },

1059

1370

{ .name = NULL }

1060

1371

};

1061

1372

1062

1373

error_t parse_opt(int key, char *arg,

1063

1374

struct argp_state *state){

1375

errno = 0;

1064

1376

switch(key){

1065

1377

case 128: /* --debug */

1066

1378

debug = true;

1082

1394

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

1083

1395

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

1084

1396

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

1085

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

1086

exit(EXIT_FAILURE);

1397

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

1087

1398

}

1088

1399

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

1089

1400

break;

1094

1405

errno = 0;

1095

1406

delay = strtof(arg, &tmp);

1096

1407

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

1097

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

1098

exit(EXIT_FAILURE);

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");

1099

1416

}

1100

1417

break;

1101

case ARGP_KEY_ARG:

1102

argp_usage(state);

1103

case ARGP_KEY_END:

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);

1104

1431

break;

1105

1432

default:

1106

1433

return ARGP_ERR_UNKNOWN;

1107

1434

}

1108

return 0;

1435

return errno;

1109

1436

}

1110

1437

1111

1438

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

1112

1439

.args_doc = "",

1113

1440

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

1114

1441

" passwords from a Mandos server" };

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;

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");

1120

1512

}

1121

1513

}

1122

1514

1123

1515

if(not debug){

1124

1516

avahi_set_log_function(empty_log);

1125

1517

}

1518

1519

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

1520

struct dirent **direntries;

1521

ret = scandir(sys_class_net, &direntries, good_interface,

1522

alphasort);

1523

if(ret >= 1){

1524

/* Pick the first good interface */

1525

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

1526

if(debug){

1527

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

1528

}

1529

if(interface == NULL){

1530

perror_plus("malloc");

1531

free(direntries);

1532

exitcode = EXIT_FAILURE;

1533

goto end;

1534

}

1535

free(direntries);

1536

} else {

1537

free(direntries);

1538

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

1539

exitcode = EXIT_FAILURE;

1540

goto end;

1541

}

1542

}

1126

1543

1127

1544

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

1128

1545

from the signal handler */

1131

1548

mc.simple_poll = avahi_simple_poll_new();

1132

1549

if(mc.simple_poll == NULL){

1133

1550

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

1134

exitcode = EXIT_FAILURE;

1551

exitcode = EX_UNAVAILABLE;

1135

1552

goto end;

1136

1553

}

1137

1554

1138

1555

sigemptyset(&sigterm_action.sa_mask);

1139

1556

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

1140

1557

if(ret == -1){

1141

perror("sigaddset");

1142

exitcode = EXIT_FAILURE;

1558

perror_plus("sigaddset");

1559

exitcode = EX_OSERR;

1143

1560

goto end;

1144

1561

}

1145

1562

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

1146

1563

if(ret == -1){

1147

perror("sigaddset");

1148

exitcode = EXIT_FAILURE;

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1149

1566

goto end;

1150

1567

}

1151

1568

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

1152

1569

if(ret == -1){

1153

perror("sigaddset");

1154

exitcode = EXIT_FAILURE;

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1155

1572

goto end;

1156

1573

}

1157

1574

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

1160

1577

*/

1161

1578

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

1162

1579

if(ret == -1){

1163

perror("sigaction");

1164

return EXIT_FAILURE;

1580

perror_plus("sigaction");

1581

return EX_OSERR;

1165

1582

}

1166

1583

if(old_sigterm_action.sa_handler != SIG_IGN){

1167

1584

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

1168

1585

if(ret == -1){

1169

perror("sigaction");

1170

exitcode = EXIT_FAILURE;

1586

perror_plus("sigaction");

1587

exitcode = EX_OSERR;

1171

1588

goto end;

1172

1589

}

1173

1590

}

1174

1591

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

1175

1592

if(ret == -1){

1176

perror("sigaction");

1177

return EXIT_FAILURE;

1593

perror_plus("sigaction");

1594

return EX_OSERR;

1178

1595

}

1179

1596

if(old_sigterm_action.sa_handler != SIG_IGN){

1180

1597

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

1181

1598

if(ret == -1){

1182

perror("sigaction");

1183

exitcode = EXIT_FAILURE;

1599

perror_plus("sigaction");

1600

exitcode = EX_OSERR;

1184

1601

goto end;

1185

1602

}

1186

1603

}

1187

1604

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

1188

1605

if(ret == -1){

1189

perror("sigaction");

1190

return EXIT_FAILURE;

1606

perror_plus("sigaction");

1607

return EX_OSERR;

1191

1608

}

1192

1609

if(old_sigterm_action.sa_handler != SIG_IGN){

1193

1610

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

1194

1611

if(ret == -1){

1195

perror("sigaction");

1196

exitcode = EXIT_FAILURE;

1612

perror_plus("sigaction");

1613

exitcode = EX_OSERR;

1197

1614

goto end;

1198

1615

}

1199

1616

}

1200

1617

1201

1618

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

1202

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

1619

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

1203

1620

if_index = (AvahiIfIndex) if_nametoindex(interface);

1204

1621

if(if_index == 0){

1205

1622

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

1206

exitcode = EXIT_FAILURE;

1623

exitcode = EX_UNAVAILABLE;

1207

1624

goto end;

1208

1625

}

1209

1626

1215

1632

errno = 0;

1216

1633

ret = seteuid(0);

1217

1634

if(ret == -1){

1218

perror("seteuid");

1635

perror_plus("seteuid");

1219

1636

}

1220

1637

1221

1638

#ifdef __linux__

1222

1639

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1223

messages to mess up the prompt */

1640

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

1224

1641

ret = klogctl(8, NULL, 5);

1225

1642

bool restore_loglevel = true;

1226

1643

if(ret == -1){

1227

1644

restore_loglevel = false;

1228

perror("klogctl");

1645

perror_plus("klogctl");

1229

1646

}

1230

1647

#endif /* __linux__ */

1231

1648

1232

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1233

1650

if(sd < 0){

1234

perror("socket");

1235

exitcode = EXIT_FAILURE;

1651

perror_plus("socket");

1652

exitcode = EX_OSERR;

1236

1653

#ifdef __linux__

1237

1654

if(restore_loglevel){

1238

1655

ret = klogctl(7, NULL, 0);

1239

1656

if(ret == -1){

1240

perror("klogctl");

1657

perror_plus("klogctl");

1241

1658

}

1242

1659

}

1243

1660

#endif /* __linux__ */

1245

1662

errno = 0;

1246

1663

ret = seteuid(uid);

1247

1664

if(ret == -1){

1248

perror("seteuid");

1665

perror_plus("seteuid");

1249

1666

}

1250

1667

goto end;

1251

1668

}

1252

1669

strcpy(network.ifr_name, interface);

1253

1670

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

1254

1671

if(ret == -1){

1255

perror("ioctl SIOCGIFFLAGS");

1672

perror_plus("ioctl SIOCGIFFLAGS");

1256

1673

#ifdef __linux__

1257

1674

if(restore_loglevel){

1258

1675

ret = klogctl(7, NULL, 0);

1259

1676

if(ret == -1){

1260

perror("klogctl");

1677

perror_plus("klogctl");

1261

1678

}

1262

1679

}

1263

1680

#endif /* __linux__ */

1264

exitcode = EXIT_FAILURE;

1681

exitcode = EX_OSERR;

1265

1682

/* Lower privileges */

1266

1683

errno = 0;

1267

1684

ret = seteuid(uid);

1268

1685

if(ret == -1){

1269

perror("seteuid");

1686

perror_plus("seteuid");

1270

1687

}

1271

1688

goto end;

1272

1689

}

1276

1693

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

1277

1694

if(ret == -1){

1278

1695

take_down_interface = false;

1279

perror("ioctl SIOCSIFFLAGS");

1280

exitcode = EXIT_FAILURE;

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1697

exitcode = EX_OSERR;

1281

1698

#ifdef __linux__

1282

1699

if(restore_loglevel){

1283

1700

ret = klogctl(7, NULL, 0);

1284

1701

if(ret == -1){

1285

perror("klogctl");

1702

perror_plus("klogctl");

1286

1703

}

1287

1704

}

1288

1705

#endif /* __linux__ */

1290

1707

errno = 0;

1291

1708

ret = seteuid(uid);

1292

1709

if(ret == -1){

1293

perror("seteuid");

1710

perror_plus("seteuid");

1294

1711

}

1295

1712

goto end;

1296

1713

}

1297

1714

}

1298

/* sleep checking until interface is running */

1715

/* Sleep checking until interface is running.

1716

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

1299

1717

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

1300

1718

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

1301

1719

if(ret == -1){

1302

perror("ioctl SIOCGIFFLAGS");

1720

perror_plus("ioctl SIOCGIFFLAGS");

1303

1721

} else if(network.ifr_flags & IFF_RUNNING){

1304

1722

break;

1305

1723

}

1306

1724

struct timespec sleeptime = { .tv_nsec = 250000000 };

1307

1725

ret = nanosleep(&sleeptime, NULL);

1308

1726

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

1309

perror("nanosleep");

1727

perror_plus("nanosleep");

1310

1728

}

1311

1729

}

1312

1730

if(not take_down_interface){

1313

1731

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

1314

1732

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

1315

1733

if(ret == -1){

1316

perror("close");

1734

perror_plus("close");

1317

1735

}

1318

1736

}

1319

1737

#ifdef __linux__

1321

1739

/* Restores kernel loglevel to default */

1322

1740

ret = klogctl(7, NULL, 0);

1323

1741

if(ret == -1){

1324

perror("klogctl");

1742

perror_plus("klogctl");

1325

1743

}

1326

1744

}

1327

1745

#endif /* __linux__ */

1331

1749

/* Lower privileges */

1332

1750

ret = seteuid(uid);

1333

1751

if(ret == -1){

1334

perror("seteuid");

1752

perror_plus("seteuid");

1335

1753

}

1336

1754

} else {

1337

1755

/* Lower privileges permanently */

1338

1756

ret = setuid(uid);

1339

1757

if(ret == -1){

1340

perror("setuid");

1758

perror_plus("setuid");

1341

1759

}

1342

1760

}

1343

1761

}

1349

1767

ret = init_gnutls_global(pubkey, seckey);

1350

1768

if(ret == -1){

1351

1769

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

1352

exitcode = EXIT_FAILURE;

1770

exitcode = EX_UNAVAILABLE;

1353

1771

goto end;

1354

1772

} else {

1355

1773

gnutls_initialized = true;

1359

1777

goto end;

1360

1778

}

1361

1779

1780

if(mkdtemp(tempdir) == NULL){

1781

perror_plus("mkdtemp");

1782

goto end;

1783

}

1362

1784

tempdir_created = true;

1363

if(mkdtemp(tempdir) == NULL){

1364

tempdir_created = false;

1365

perror("mkdtemp");

1366

goto end;

1367

}

1368

1785

1369

1786

if(quit_now){

1370

1787

goto end;

1372

1789

1373

1790

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

1374

1791

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

1375

exitcode = EXIT_FAILURE;

1792

exitcode = EX_UNAVAILABLE;

1376

1793

goto end;

1377

1794

} else {

1378

1795

gpgme_initialized = true;

1388

1805

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

1389

1806

if(address == NULL){

1390

1807

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

1391

exitcode = EXIT_FAILURE;

1808

exitcode = EX_USAGE;

1392

1809

goto end;

1393

1810

}

1394

1811

1402

1819

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

1403

1820

or tmpmax != (uint16_t)tmpmax){

1404

1821

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

1405

exitcode = EXIT_FAILURE;

1822

exitcode = EX_USAGE;

1406

1823

goto end;

1407

1824

}

1408

1825

1424

1841

if(quit_now){

1425

1842

goto end;

1426

1843

}

1427

1428

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

1429

if(ret < 0){

1430

exitcode = EXIT_FAILURE;

1431

} else {

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){

1432

1854

exitcode = EXIT_SUCCESS;

1433

1855

}

1856

1434

1857

goto end;

1435

1858

}

1436

1859

1460

1883

if(mc.server == NULL){

1461

1884

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

1462

1885

avahi_strerror(error));

1463

exitcode = EXIT_FAILURE;

1886

exitcode = EX_UNAVAILABLE;

1464

1887

goto end;

1465

1888

}

1466

1889

1475

1898

if(sb == NULL){

1476

1899

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

1477

1900

avahi_strerror(avahi_server_errno(mc.server)));

1478

exitcode = EXIT_FAILURE;

1901

exitcode = EX_UNAVAILABLE;

1479

1902

goto end;

1480

1903

}

1481

1904

1488

1911

if(debug){

1489

1912

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

1490

1913

}

1491

1492

avahi_simple_poll_loop(mc.simple_poll);

1914

1915

ret = avahi_loop_with_timeout(mc.simple_poll,

1916

(int)(retry_interval * 1000));

1917

if(debug){

1918

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

1919

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

1920

}

1493

1921

1494

1922

end:

1495

1923

1516

1944

if(gpgme_initialized){

1517

1945

gpgme_release(mc.ctx);

1518

1946

}

1947

1948

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

1949

has seen */

1950

if(mc.current_server != NULL){

1951

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

1952

while(mc.current_server != NULL){

1953

server *next = mc.current_server->next;

1954

free(mc.current_server);

1955

mc.current_server = next;

1956

}

1957

}

1519

1958

1520

1959

/* Take down the network interface */

1521

1960

if(take_down_interface){

1523

1962

errno = 0;

1524

1963

ret = seteuid(0);

1525

1964

if(ret == -1){

1526

perror("seteuid");

1965

perror_plus("seteuid");

1527

1966

}

1528

1967

if(geteuid() == 0){

1529

1968

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

1530

1969

if(ret == -1){

1531

perror("ioctl SIOCGIFFLAGS");

1970

perror_plus("ioctl SIOCGIFFLAGS");

1532

1971

} else if(network.ifr_flags & IFF_UP) {

1533

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

1972

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

1534

1973

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

1535

1974

if(ret == -1){

1536

perror("ioctl SIOCSIFFLAGS");

1975

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1537

1976

}

1538

1977

}

1539

1978

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

1540

1979

if(ret == -1){

1541

perror("close");

1980

perror_plus("close");

1542

1981

}

1543

1982

/* Lower privileges permanently */

1544

1983

errno = 0;

1545

1984

ret = setuid(uid);

1546

1985

if(ret == -1){

1547

perror("setuid");

1986

perror_plus("setuid");

1548

1987

}

1549

1988

}

1550

1989

}

1551

1990

1552

/* Removes the temp directory used by GPGME */

1991

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

1553

1992

if(tempdir_created){

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

}

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];

1574

1999

char *fullname = NULL;

1575

2000

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

1576

2001

direntry->d_name);

1577

2002

if(ret < 0){

1578

perror("asprintf");

2003

perror_plus("asprintf");

1579

2004

continue;

1580

2005

}

1581

2006

ret = remove(fullname);

1585

2010

}

1586

2011

free(fullname);

1587

2012

}

1588

closedir(d);

2013

}

2014

2015

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

2016

specify */

2017

free(direntries);

2018

if (ret == -1){

2019

perror_plus("scandir");

1589

2020

}

1590

2021

ret = rmdir(tempdir);

1591

2022

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

1592

perror("rmdir");

2023

perror_plus("rmdir");

1593

2024

}

1594

2025

}

1595

2026

1600

2031

&old_sigterm_action,

1601

2032

NULL));

1602

2033

if(ret == -1){

1603

perror("sigaction");

2034

perror_plus("sigaction");

1604

2035

}

1605

2036

do {

1606

2037

ret = raise(signal_received);

1607

2038

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

1608

2039

if(ret != 0){

1609

perror("raise");

2040

perror_plus("raise");

1610

2041

abort();

1611

2042

}

1612

2043

TEMP_FAILURE_RETRY(pause());