/mandos/release : revision 237.7.35

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() */

128

131

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

129

132

char *connect_to = NULL;

130

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

131

145

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

132

146

typedef struct {

133

147

AvahiSimplePoll *simple_poll;

137

151

gnutls_dh_params_t dh_params;

138

152

const char *priority;

139

153

gpgme_ctx_t ctx;

154

server *current_server;

140

155

} mandos_context;

141

156

142

157

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

143

158

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

144

159

.dh_bits = 1024, .priority = "SECURE256"

145

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

160

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

161

.current_server = NULL };

146

162

147

163

sig_atomic_t quit_now = 0;

148

164

int signal_received = 0;

149

165

166

/* Function to use when printing errors */

167

void perror_plus(const char *print_text){

168

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

169

program_invocation_short_name);

170

perror(print_text);

171

}

172

150

173

/*

151

174

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

152

175

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

164

187

return buffer_capacity;

165

188

}

166

189

190

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

167

227

/*

168

228

* Initialize GPGME.

169

229

*/

183

243

184

244

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

185

245

if(fd == -1){

186

perror("open");

246

perror_plus("open");

187

247

return false;

188

248

}

189

249

203

263

204

264

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

205

265

if(ret == -1){

206

perror("close");

266

perror_plus("close");

207

267

}

208

268

gpgme_data_release(pgp_data);

209

269

return true;

334

394

335

395

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

336

396

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

337

perror("gpgme_data_seek");

397

perror_plus("gpgme_data_seek");

338

398

plaintext_length = -1;

339

399

goto decrypt_end;

340

400

}

345

405

(size_t)plaintext_length,

346

406

plaintext_capacity);

347

407

if(plaintext_capacity == 0){

348

perror("incbuffer");

408

perror_plus("incbuffer");

349

409

plaintext_length = -1;

350

410

goto decrypt_end;

351

411

}

358

418

break;

359

419

}

360

420

if(ret < 0){

361

perror("gpgme_data_read");

421

perror_plus("gpgme_data_read");

362

422

plaintext_length = -1;

363

423

goto decrypt_end;

364

424

}

421

481

}

422

482

423

483

/* OpenPGP credentials */

424

gnutls_certificate_allocate_credentials(&mc.cred);

484

ret = gnutls_certificate_allocate_credentials(&mc.cred);

425

485

if(ret != GNUTLS_E_SUCCESS){

426

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

427

from

428

-Wunreachable-code

429

*/

486

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

430

487

safer_gnutls_strerror(ret));

431

488

gnutls_global_deinit();

432

489

return -1;

554

611

gnutls_session_t session;

555

612

int pf; /* Protocol family */

556

613

614

errno = 0;

615

557

616

if(quit_now){

617

errno = EINTR;

558

618

return -1;

559

619

}

560

620

567

627

break;

568

628

default:

569

629

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

630

errno = EINVAL;

570

631

return -1;

571

632

}

572

633

582

643

583

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

584

645

if(tcp_sd < 0){

585

perror("socket");

646

int e = errno;

647

perror_plus("socket");

648

errno = e;

586

649

goto mandos_end;

587

650

}

588

651

589

652

if(quit_now){

653

errno = EINTR;

590

654

goto mandos_end;

591

655

}

592

656

599

663

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

600

664

}

601

665

if(ret < 0 ){

602

perror("inet_pton");

666

int e = errno;

667

perror_plus("inet_pton");

668

errno = e;

603

669

goto mandos_end;

604

670

}

605

671

if(ret == 0){

672

int e = errno;

606

673

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

674

errno = e;

607

675

goto mandos_end;

608

676

}

609

677

if(af == AF_INET6){

617

685

if(if_index == AVAHI_IF_UNSPEC){

618

686

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

619

687

" without a network interface\n");

688

errno = EINVAL;

620

689

goto mandos_end;

621

690

}

622

691

/* Set the network interface number as scope */

629

698

}

630

699

631

700

if(quit_now){

701

errno = EINTR;

632

702

goto mandos_end;

633

703

}

634

704

636

706

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

637

707

char interface[IF_NAMESIZE];

638

708

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

639

perror("if_indextoname");

709

perror_plus("if_indextoname");

640

710

} else {

641

711

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

642

712

ip, interface, port);

656

726

sizeof(addrstr));

657

727

}

658

728

if(pcret == NULL){

659

perror("inet_ntop");

729

perror_plus("inet_ntop");

660

730

} else {

661

731

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

662

732

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

665

735

}

666

736

667

737

if(quit_now){

738

errno = EINTR;

668

739

goto mandos_end;

669

740

}

670

741

674

745

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

675

746

}

676

747

if(ret < 0){

677

perror("connect");

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

678

753

goto mandos_end;

679

754

}

680

755

681

756

if(quit_now){

757

errno = EINTR;

682

758

goto mandos_end;

683

759

}

684

760

689

765

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

690

766

out_size - written));

691

767

if(ret == -1){

692

perror("write");

768

int e = errno;

769

perror_plus("write");

770

errno = e;

693

771

goto mandos_end;

694

772

}

695

773

written += (size_t)ret;

705

783

}

706

784

707

785

if(quit_now){

786

errno = EINTR;

708

787

goto mandos_end;

709

788

}

710

789

}

714

793

}

715

794

716

795

if(quit_now){

796

errno = EINTR;

717

797

goto mandos_end;

718

798

}

719

799

800

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

720

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

721

802

722

803

if(quit_now){

804

errno = EINTR;

723

805

goto mandos_end;

724

806

}

725

807

726

808

do {

727

809

ret = gnutls_handshake(session);

728

810

if(quit_now){

811

errno = EINTR;

729

812

goto mandos_end;

730

813

}

731

814

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

735

818

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

736

819

gnutls_perror(ret);

737

820

}

821

errno = EPROTO;

738

822

goto mandos_end;

739

823

}

740

824

748

832

while(true){

749

833

750

834

if(quit_now){

835

errno = EINTR;

751

836

goto mandos_end;

752

837

}

753

838

754

839

buffer_capacity = incbuffer(&buffer, buffer_length,

755

840

buffer_capacity);

756

841

if(buffer_capacity == 0){

757

perror("incbuffer");

842

int e = errno;

843

perror_plus("incbuffer");

844

errno = e;

758

845

goto mandos_end;

759

846

}

760

847

761

848

if(quit_now){

849

errno = EINTR;

762

850

goto mandos_end;

763

851

}

764

852

777

865

ret = gnutls_handshake(session);

778

866

779

867

if(quit_now){

868

errno = EINTR;

780

869

goto mandos_end;

781

870

}

782

871

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

783

872

if(ret < 0){

784

873

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

785

874

gnutls_perror(ret);

875

errno = EPROTO;

786

876

goto mandos_end;

787

877

}

788

878

break;

790

880

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

791

881

" encrypted session with Mandos server\n");

792

882

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

errno = EIO;

793

884

goto mandos_end;

794

885

}

795

886

} else {

802

893

}

803

894

804

895

if(quit_now){

896

errno = EINTR;

805

897

goto mandos_end;

806

898

}

807

899

808

900

do {

809

901

ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);

810

902

if(quit_now){

903

errno = EINTR;

811

904

goto mandos_end;

812

905

}

813

906

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

822

915

written = 0;

823

916

while(written < (size_t) decrypted_buffer_size){

824

917

if(quit_now){

918

errno = EINTR;

825

919

goto mandos_end;

826

920

}

827

921

829

923

(size_t)decrypted_buffer_size - written,

830

924

stdout);

831

925

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

926

int e = errno;

832

927

if(debug){

833

928

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

834

929

strerror(errno));

835

930

}

931

errno = e;

836

932

goto mandos_end;

837

933

}

838

934

written += (size_t)ret;

844

940

/* Shutdown procedure */

845

941

846

942

mandos_end:

847

free(decrypted_buffer);

848

free(buffer);

849

if(tcp_sd >= 0){

850

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

851

}

852

if(ret == -1){

853

perror("close");

854

}

855

gnutls_deinit(session);

856

if(quit_now){

857

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

}

858

962

}

859

963

return retval;

860

964

}

903

1007

avahi_proto_to_af(proto));

904

1008

if(ret == 0){

905

1009

avahi_simple_poll_quit(mc.simple_poll);

1010

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

906

1013

}

907

1014

}

908

1015

}

962

1069

}

963

1070

}

964

1071

965

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

1072

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

966

1073

static void handle_sigterm(int sig){

967

1074

if(quit_now){

968

1075

return;

970

1077

quit_now = 1;

971

1078

signal_received = sig;

972

1079

int old_errno = errno;

1080

/* set main loop to exit */

973

1081

if(mc.simple_poll != NULL){

974

1082

avahi_simple_poll_quit(mc.simple_poll);

975

1083

}

984

1092

int good_interface(const struct dirent *if_entry){

985

1093

ssize_t ssret;

986

1094

char *flagname = NULL;

1095

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

1096

return 0;

1097

}

987

1098

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

988

1099

if_entry->d_name);

989

1100

if(ret < 0){

990

perror("asprintf");

991

return 0;

992

}

993

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

1101

perror_plus("asprintf");

994

1102

return 0;

995

1103

}

996

1104

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

997

1105

if(flags_fd == -1){

998

perror("open");

1106

perror_plus("open");

1107

free(flagname);

999

1108

return 0;

1000

1109

}

1110

free(flagname);

1001

1111

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

1002

1112

/* read line from flags_fd */

1003

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

1004

char *flagstring = malloc((size_t)to_read);

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';

1005

1116

if(flagstring == NULL){

1006

perror("malloc");

1117

perror_plus("malloc");

1007

1118

close(flags_fd);

1008

1119

return 0;

1009

1120

}

1011

1122

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

1012

1123

(size_t)to_read));

1013

1124

if(ssret == -1){

1014

perror("read");

1125

perror_plus("read");

1015

1126

free(flagstring);

1016

1127

close(flags_fd);

1017

1128

return 0;

1029

1140

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

1030

1141

and not (isspace(*tmp)))

1031

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

}

1032

1147

free(flagstring);

1033

1148

return 0;

1034

1149

}

1036

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1037

1152

/* Reject the loopback device */

1038

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1039

1158

return 0;

1040

1159

}

1041

1160

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

1042

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

}

1043

1166

return 1;

1044

1167

}

1045

1168

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

1046

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

}

1047

1182

return 0;

1048

1183

}

1049

1184

/* Accept this device */

1050

return 1;

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

}

1051

1272

}

1052

1273

1053

1274

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

1072

1293

bool gnutls_initialized = false;

1073

1294

bool gpgme_initialized = false;

1074

1295

float delay = 2.5f;

1296

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

1297

retrying the same server again */

1075

1298

1076

1299

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1077

1300

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1083

1306

errno = 0;

1084

1307

ret = setgid(gid);

1085

1308

if(ret == -1){

1086

perror("setgid");

1309

perror_plus("setgid");

1087

1310

}

1088

1311

1089

1312

/* Lower user privileges (temporarily) */

1090

1313

errno = 0;

1091

1314

ret = seteuid(uid);

1092

1315

if(ret == -1){

1093

perror("seteuid");

1316

perror_plus("seteuid");

1094

1317

}

1095

1318

1096

1319

if(quit_now){

1131

1354

.arg = "SECONDS",

1132

1355

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

1133

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 },

1134

1370

{ .name = NULL }

1135

1371

};

1136

1372

1137

1373

error_t parse_opt(int key, char *arg,

1138

1374

struct argp_state *state){

1375

errno = 0;

1139

1376

switch(key){

1140

1377

case 128: /* --debug */

1141

1378

debug = true;

1157

1394

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

1158

1395

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

1159

1396

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

1160

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

1161

exit(EXIT_FAILURE);

1397

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

1162

1398

}

1163

1399

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

1164

1400

break;

1169

1405

errno = 0;

1170

1406

delay = strtof(arg, &tmp);

1171

1407

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

1172

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

1173

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");

1174

1416

}

1175

1417

break;

1176

case ARGP_KEY_ARG:

1177

argp_usage(state);

1178

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);

1179

1431

break;

1180

1432

default:

1181

1433

return ARGP_ERR_UNKNOWN;

1182

1434

}

1183

return 0;

1435

return errno;

1184

1436

}

1185

1437

1186

1438

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

1187

1439

.args_doc = "",

1188

1440

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

1189

1441

" passwords from a Mandos server" };

1190

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

1191

if(ret == ARGP_ERR_UNKNOWN){

1192

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

1193

exitcode = EXIT_FAILURE;

1194

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");

1195

1512

}

1196

1513

}

1197

1514

1206

1523

if(ret >= 1){

1207

1524

/* Pick the first good interface */

1208

1525

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

1526

if(debug){

1527

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

1528

}

1209

1529

if(interface == NULL){

1210

perror("malloc");

1530

perror_plus("malloc");

1211

1531

free(direntries);

1212

1532

exitcode = EXIT_FAILURE;

1213

1533

goto end;

1228

1548

mc.simple_poll = avahi_simple_poll_new();

1229

1549

if(mc.simple_poll == NULL){

1230

1550

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

1231

exitcode = EXIT_FAILURE;

1551

exitcode = EX_UNAVAILABLE;

1232

1552

goto end;

1233

1553

}

1234

1554

1235

1555

sigemptyset(&sigterm_action.sa_mask);

1236

1556

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

1237

1557

if(ret == -1){

1238

perror("sigaddset");

1239

exitcode = EXIT_FAILURE;

1558

perror_plus("sigaddset");

1559

exitcode = EX_OSERR;

1240

1560

goto end;

1241

1561

}

1242

1562

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

1243

1563

if(ret == -1){

1244

perror("sigaddset");

1245

exitcode = EXIT_FAILURE;

1564

perror_plus("sigaddset");

1565

exitcode = EX_OSERR;

1246

1566

goto end;

1247

1567

}

1248

1568

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

1249

1569

if(ret == -1){

1250

perror("sigaddset");

1251

exitcode = EXIT_FAILURE;

1570

perror_plus("sigaddset");

1571

exitcode = EX_OSERR;

1252

1572

goto end;

1253

1573

}

1254

1574

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

1257

1577

*/

1258

1578

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

1259

1579

if(ret == -1){

1260

perror("sigaction");

1261

return EXIT_FAILURE;

1580

perror_plus("sigaction");

1581

return EX_OSERR;

1262

1582

}

1263

1583

if(old_sigterm_action.sa_handler != SIG_IGN){

1264

1584

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

1265

1585

if(ret == -1){

1266

perror("sigaction");

1267

exitcode = EXIT_FAILURE;

1586

perror_plus("sigaction");

1587

exitcode = EX_OSERR;

1268

1588

goto end;

1269

1589

}

1270

1590

}

1271

1591

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

1272

1592

if(ret == -1){

1273

perror("sigaction");

1274

return EXIT_FAILURE;

1593

perror_plus("sigaction");

1594

return EX_OSERR;

1275

1595

}

1276

1596

if(old_sigterm_action.sa_handler != SIG_IGN){

1277

1597

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

1278

1598

if(ret == -1){

1279

perror("sigaction");

1280

exitcode = EXIT_FAILURE;

1599

perror_plus("sigaction");

1600

exitcode = EX_OSERR;

1281

1601

goto end;

1282

1602

}

1283

1603

}

1284

1604

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

1285

1605

if(ret == -1){

1286

perror("sigaction");

1287

return EXIT_FAILURE;

1606

perror_plus("sigaction");

1607

return EX_OSERR;

1288

1608

}

1289

1609

if(old_sigterm_action.sa_handler != SIG_IGN){

1290

1610

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

1291

1611

if(ret == -1){

1292

perror("sigaction");

1293

exitcode = EXIT_FAILURE;

1612

perror_plus("sigaction");

1613

exitcode = EX_OSERR;

1294

1614

goto end;

1295

1615

}

1296

1616

}

1300

1620

if_index = (AvahiIfIndex) if_nametoindex(interface);

1301

1621

if(if_index == 0){

1302

1622

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

1303

exitcode = EXIT_FAILURE;

1623

exitcode = EX_UNAVAILABLE;

1304

1624

goto end;

1305

1625

}

1306

1626

1312

1632

errno = 0;

1313

1633

ret = seteuid(0);

1314

1634

if(ret == -1){

1315

perror("seteuid");

1635

perror_plus("seteuid");

1316

1636

}

1317

1637

1318

1638

#ifdef __linux__

1319

1639

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1320

messages to mess up the prompt */

1640

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

1321

1641

ret = klogctl(8, NULL, 5);

1322

1642

bool restore_loglevel = true;

1323

1643

if(ret == -1){

1324

1644

restore_loglevel = false;

1325

perror("klogctl");

1645

perror_plus("klogctl");

1326

1646

}

1327

1647

#endif /* __linux__ */

1328

1648

1329

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1330

1650

if(sd < 0){

1331

perror("socket");

1332

exitcode = EXIT_FAILURE;

1651

perror_plus("socket");

1652

exitcode = EX_OSERR;

1333

1653

#ifdef __linux__

1334

1654

if(restore_loglevel){

1335

1655

ret = klogctl(7, NULL, 0);

1336

1656

if(ret == -1){

1337

perror("klogctl");

1657

perror_plus("klogctl");

1338

1658

}

1339

1659

}

1340

1660

#endif /* __linux__ */

1342

1662

errno = 0;

1343

1663

ret = seteuid(uid);

1344

1664

if(ret == -1){

1345

perror("seteuid");

1665

perror_plus("seteuid");

1346

1666

}

1347

1667

goto end;

1348

1668

}

1349

1669

strcpy(network.ifr_name, interface);

1350

1670

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

1351

1671

if(ret == -1){

1352

perror("ioctl SIOCGIFFLAGS");

1672

perror_plus("ioctl SIOCGIFFLAGS");

1353

1673

#ifdef __linux__

1354

1674

if(restore_loglevel){

1355

1675

ret = klogctl(7, NULL, 0);

1356

1676

if(ret == -1){

1357

perror("klogctl");

1677

perror_plus("klogctl");

1358

1678

}

1359

1679

}

1360

1680

#endif /* __linux__ */

1361

exitcode = EXIT_FAILURE;

1681

exitcode = EX_OSERR;

1362

1682

/* Lower privileges */

1363

1683

errno = 0;

1364

1684

ret = seteuid(uid);

1365

1685

if(ret == -1){

1366

perror("seteuid");

1686

perror_plus("seteuid");

1367

1687

}

1368

1688

goto end;

1369

1689

}

1373

1693

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

1374

1694

if(ret == -1){

1375

1695

take_down_interface = false;

1376

perror("ioctl SIOCSIFFLAGS");

1377

exitcode = EXIT_FAILURE;

1696

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1697

exitcode = EX_OSERR;

1378

1698

#ifdef __linux__

1379

1699

if(restore_loglevel){

1380

1700

ret = klogctl(7, NULL, 0);

1381

1701

if(ret == -1){

1382

perror("klogctl");

1702

perror_plus("klogctl");

1383

1703

}

1384

1704

}

1385

1705

#endif /* __linux__ */

1387

1707

errno = 0;

1388

1708

ret = seteuid(uid);

1389

1709

if(ret == -1){

1390

perror("seteuid");

1710

perror_plus("seteuid");

1391

1711

}

1392

1712

goto end;

1393

1713

}

1394

1714

}

1395

/* sleep checking until interface is running */

1715

/* Sleep checking until interface is running.

1716

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

1396

1717

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

1397

1718

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

1398

1719

if(ret == -1){

1399

perror("ioctl SIOCGIFFLAGS");

1720

perror_plus("ioctl SIOCGIFFLAGS");

1400

1721

} else if(network.ifr_flags & IFF_RUNNING){

1401

1722

break;

1402

1723

}

1403

1724

struct timespec sleeptime = { .tv_nsec = 250000000 };

1404

1725

ret = nanosleep(&sleeptime, NULL);

1405

1726

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

1406

perror("nanosleep");

1727

perror_plus("nanosleep");

1407

1728

}

1408

1729

}

1409

1730

if(not take_down_interface){

1410

1731

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

1411

1732

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

1412

1733

if(ret == -1){

1413

perror("close");

1734

perror_plus("close");

1414

1735

}

1415

1736

}

1416

1737

#ifdef __linux__

1418

1739

/* Restores kernel loglevel to default */

1419

1740

ret = klogctl(7, NULL, 0);

1420

1741

if(ret == -1){

1421

perror("klogctl");

1742

perror_plus("klogctl");

1422

1743

}

1423

1744

}

1424

1745

#endif /* __linux__ */

1428

1749

/* Lower privileges */

1429

1750

ret = seteuid(uid);

1430

1751

if(ret == -1){

1431

perror("seteuid");

1752

perror_plus("seteuid");

1432

1753

}

1433

1754

} else {

1434

1755

/* Lower privileges permanently */

1435

1756

ret = setuid(uid);

1436

1757

if(ret == -1){

1437

perror("setuid");

1758

perror_plus("setuid");

1438

1759

}

1439

1760

}

1440

1761

}

1446

1767

ret = init_gnutls_global(pubkey, seckey);

1447

1768

if(ret == -1){

1448

1769

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

1449

exitcode = EXIT_FAILURE;

1770

exitcode = EX_UNAVAILABLE;

1450

1771

goto end;

1451

1772

} else {

1452

1773

gnutls_initialized = true;

1456

1777

goto end;

1457

1778

}

1458

1779

1780

if(mkdtemp(tempdir) == NULL){

1781

perror_plus("mkdtemp");

1782

goto end;

1783

}

1459

1784

tempdir_created = true;

1460

if(mkdtemp(tempdir) == NULL){

1461

tempdir_created = false;

1462

perror("mkdtemp");

1463

goto end;

1464

}

1465

1785

1466

1786

if(quit_now){

1467

1787

goto end;

1469

1789

1470

1790

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

1471

1791

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

1472

exitcode = EXIT_FAILURE;

1792

exitcode = EX_UNAVAILABLE;

1473

1793

goto end;

1474

1794

} else {

1475

1795

gpgme_initialized = true;

1485

1805

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

1486

1806

if(address == NULL){

1487

1807

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

1488

exitcode = EXIT_FAILURE;

1808

exitcode = EX_USAGE;

1489

1809

goto end;

1490

1810

}

1491

1811

1499

1819

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

1500

1820

or tmpmax != (uint16_t)tmpmax){

1501

1821

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

1502

exitcode = EXIT_FAILURE;

1822

exitcode = EX_USAGE;

1503

1823

goto end;

1504

1824

}

1505

1825

1521

1841

if(quit_now){

1522

1842

goto end;

1523

1843

}

1524

1525

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

1526

if(ret < 0){

1527

exitcode = EXIT_FAILURE;

1528

} 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){

1529

1854

exitcode = EXIT_SUCCESS;

1530

1855

}

1856

1531

1857

goto end;

1532

1858

}

1533

1859

1557

1883

if(mc.server == NULL){

1558

1884

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

1559

1885

avahi_strerror(error));

1560

exitcode = EXIT_FAILURE;

1886

exitcode = EX_UNAVAILABLE;

1561

1887

goto end;

1562

1888

}

1563

1889

1572

1898

if(sb == NULL){

1573

1899

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

1574

1900

avahi_strerror(avahi_server_errno(mc.server)));

1575

exitcode = EXIT_FAILURE;

1901

exitcode = EX_UNAVAILABLE;

1576

1902

goto end;

1577

1903

}

1578

1904

1585

1911

if(debug){

1586

1912

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

1587

1913

}

1588

1589

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

}

1590

1921

1591

1922

end:

1592

1923

1613

1944

if(gpgme_initialized){

1614

1945

gpgme_release(mc.ctx);

1615

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

}

1616

1958

1617

1959

/* Take down the network interface */

1618

1960

if(take_down_interface){

1620

1962

errno = 0;

1621

1963

ret = seteuid(0);

1622

1964

if(ret == -1){

1623

perror("seteuid");

1965

perror_plus("seteuid");

1624

1966

}

1625

1967

if(geteuid() == 0){

1626

1968

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

1627

1969

if(ret == -1){

1628

perror("ioctl SIOCGIFFLAGS");

1970

perror_plus("ioctl SIOCGIFFLAGS");

1629

1971

} else if(network.ifr_flags & IFF_UP) {

1630

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

1972

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

1631

1973

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

1632

1974

if(ret == -1){

1633

perror("ioctl SIOCSIFFLAGS");

1975

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1634

1976

}

1635

1977

}

1636

1978

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

1637

1979

if(ret == -1){

1638

perror("close");

1980

perror_plus("close");

1639

1981

}

1640

1982

/* Lower privileges permanently */

1641

1983

errno = 0;

1642

1984

ret = setuid(uid);

1643

1985

if(ret == -1){

1644

perror("setuid");

1986

perror_plus("setuid");

1645

1987

}

1646

1988

}

1647

1989

}

1648

1990

1649

/* Removes the temp directory used by GPGME */

1991

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

1650

1992

if(tempdir_created){

1651

DIR *d;

1652

struct dirent *direntry;

1653

d = opendir(tempdir);

1654

if(d == NULL){

1655

if(errno != ENOENT){

1656

perror("opendir");

1657

}

1658

} else {

1659

while(true){

1660

direntry = readdir(d);

1661

if(direntry == NULL){

1662

break;

1663

}

1664

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

1665

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

1666

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

1667

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

1668

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

1669

continue;

1670

}

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];

1671

1999

char *fullname = NULL;

1672

2000

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

1673

2001

direntry->d_name);

1674

2002

if(ret < 0){

1675

perror("asprintf");

2003

perror_plus("asprintf");

1676

2004

continue;

1677

2005

}

1678

2006

ret = remove(fullname);

1682

2010

}

1683

2011

free(fullname);

1684

2012

}

1685

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");

1686

2020

}

1687

2021

ret = rmdir(tempdir);

1688

2022

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

1689

perror("rmdir");

2023

perror_plus("rmdir");

1690

2024

}

1691

2025

}

1692

2026

1697

2031

&old_sigterm_action,

1698

2032

NULL));

1699

2033

if(ret == -1){

1700

perror("sigaction");

2034

perror_plus("sigaction");

1701

2035

}

1702

2036

do {

1703

2037

ret = raise(signal_received);

1704

2038

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

1705

2039

if(ret != 0){

1706

perror("raise");

2040

perror_plus("raise");

1707

2041

abort();

1708

2042

}

1709

2043

TEMP_FAILURE_RETRY(pause());