/mandos/trunk : revision 662

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

41

42

#include <stdio.h> /* fprintf(), stderr, fwrite(),

43

stdout, ferror(), remove() */

44

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

44

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

45

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

46

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

47

strtof(), abort() */

61

*/

62

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

63

strtoimax() */

64

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

65

64

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

66

65

program_invocation_short_name */

67

66

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

73

72

*/

74

73

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

75

74

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

76

setgid(), pause() */

75

setgid(), pause(), _exit() */

77

76

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

78

77

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

79

78

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

87

86

EX_NOHOST, EX_IOERR, EX_PROTOCOL */

88

87

#include <sys/wait.h> /* waitpid(), WIFEXITED(),

89

88

WEXITSTATUS(), WTERMSIG() */

89

#include <grp.h> /* setgroups() */

90

#include <argz.h> /* argz_add_sep(), argz_next(),

91

argz_delete(), argz_append(),

92

argz_stringify(), argz_add(),

93

argz_count() */

90

94

91

95

#ifdef __linux__

92

96

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

134

138

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

135

139

char *connect_to = NULL;

136

140

const char *hookdir = HOOKDIR;

141

uid_t uid = 65534;

142

gid_t gid = 65534;

137

143

138

144

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

139

145

typedef struct server{

140

146

const char *ip;

141

uint16_t port;

147

in_port_t port;

142

148

AvahiIfIndex if_index;

143

149

int af;

144

150

struct timespec last_seen;

148

154

149

155

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

150

156

typedef struct {

151

AvahiSimplePoll *simple_poll;

152

157

AvahiServer *server;

153

158

gnutls_certificate_credentials_t cred;

154

159

unsigned int dh_bits;

156

161

const char *priority;

157

162

gpgme_ctx_t ctx;

158

163

server *current_server;

164

char *interfaces;

165

size_t interfaces_size;

159

166

} mandos_context;

160

167

161

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

162

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

163

.dh_bits = 1024, .priority = "SECURE256"

164

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

165

.current_server = NULL };

168

/* global so signal handler can reach it*/

169

AvahiSimplePoll *simple_poll;

166

170

167

171

sig_atomic_t quit_now = 0;

168

172

int signal_received = 0;

169

173

170

174

/* Function to use when printing errors */

171

175

void perror_plus(const char *print_text){

176

int e = errno;

172

177

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

173

178

program_invocation_short_name);

179

errno = e;

174

180

perror(print_text);

175

181

}

176

182

183

__attribute__((format (gnu_printf, 2, 3)))

177

184

int fprintf_plus(FILE *stream, const char *format, ...){

178

185

va_list ap;

179

186

va_start (ap, format);

180

187

181

188

TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",

182

189

program_invocation_short_name));

183

return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

190

return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));

184

191

}

185

192

186

193

/*

201

208

}

202

209

203

210

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

204

int add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,

205

int af){

211

bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,

212

int af, server **current_server){

206

213

int ret;

207

214

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

208

215

if(new_server == NULL){

209

216

perror_plus("malloc");

210

return -1;

217

return false;

211

218

}

212

219

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

213

220

.port = port,

215

222

.af = af };

216

223

if(new_server->ip == NULL){

217

224

perror_plus("strdup");

218

return -1;

225

return false;

219

226

}

220

227

/* Special case of first server */

221

if (mc.current_server == NULL){

228

if(*current_server == NULL){

222

229

new_server->next = new_server;

223

230

new_server->prev = new_server;

224

mc.current_server = new_server;

231

*current_server = new_server;

225

232

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

226

233

} else {

227

new_server->next = mc.current_server;

228

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

234

new_server->next = *current_server;

235

new_server->prev = (*current_server)->prev;

229

236

new_server->prev->next = new_server;

230

mc.current_server->prev = new_server;

237

(*current_server)->prev = new_server;

231

238

}

232

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

239

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

233

240

if(ret == -1){

234

241

perror_plus("clock_gettime");

235

return -1;

242

return false;

236

243

}

237

return 0;

244

return true;

238

245

}

239

246

240

247

/*

241

248

* Initialize GPGME.

242

249

*/

243

250

static bool init_gpgme(const char *seckey, const char *pubkey,

244

const char *tempdir){

251

const char *tempdir, mandos_context *mc){

245

252

gpgme_error_t rc;

246

253

gpgme_engine_info_t engine_info;

247

254

248

249

255

/*

250

256

* Helper function to insert pub and seckey to the engine keyring.

251

257

*/

267

273

return false;

268

274

}

269

275

270

rc = gpgme_op_import(mc.ctx, pgp_data);

276

rc = gpgme_op_import(mc->ctx, pgp_data);

271

277

if(rc != GPG_ERR_NO_ERROR){

272

278

fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",

273

279

gpgme_strsource(rc), gpgme_strerror(rc));

317

323

}

318

324

319

325

/* Create new GPGME "context" */

320

rc = gpgme_new(&(mc.ctx));

326

rc = gpgme_new(&(mc->ctx));

321

327

if(rc != GPG_ERR_NO_ERROR){

322

328

fprintf_plus(stderr, "Mandos plugin mandos-client: "

323

329

"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),

338

344

*/

339

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

346

size_t crypto_size,

341

char **plaintext){

347

char **plaintext,

348

mandos_context *mc){

342

349

gpgme_data_t dh_crypto, dh_plain;

343

350

gpgme_error_t rc;

344

351

ssize_t ret;

370

377

371

378

/* Decrypt data from the cryptotext data buffer to the plaintext

372

379

data buffer */

373

rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);

380

rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);

374

381

if(rc != GPG_ERR_NO_ERROR){

375

382

fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",

376

383

gpgme_strsource(rc), gpgme_strerror(rc));

377

384

plaintext_length = -1;

378

385

if(debug){

379

386

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

387

result = gpgme_op_decrypt_result(mc->ctx);

381

388

if(result == NULL){

382

389

fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");

383

390

} else {

461

468

}

462

469

463

470

static const char * safer_gnutls_strerror(int value){

464

const char *ret = gnutls_strerror(value); /* Spurious warning from

465

-Wunreachable-code */

471

const char *ret = gnutls_strerror(value);

466

472

if(ret == NULL)

467

473

ret = "(unknown)";

468

474

return ret;

475

481

}

476

482

477

483

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

484

const char *seckeyfilename,

485

mandos_context *mc){

479

486

int ret;

480

487

481

488

if(debug){

498

505

}

499

506

500

507

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

508

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

509

if(ret != GNUTLS_E_SUCCESS){

503

510

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

504

511

safer_gnutls_strerror(ret));

514

521

}

515

522

516

523

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

524

(mc->cred, pubkeyfilename, seckeyfilename,

518

525

GNUTLS_OPENPGP_FMT_BASE64);

519

526

if(ret != GNUTLS_E_SUCCESS){

520

527

fprintf_plus(stderr,

526

533

}

527

534

528

535

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

536

ret = gnutls_dh_params_init(&mc->dh_params);

530

537

if(ret != GNUTLS_E_SUCCESS){

531

538

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

539

" initialization: %s\n",

533

540

safer_gnutls_strerror(ret));

534

541

goto globalfail;

535

542

}

536

ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);

543

ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);

537

544

if(ret != GNUTLS_E_SUCCESS){

538

545

fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",

539

546

safer_gnutls_strerror(ret));

540

547

goto globalfail;

541

548

}

542

549

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

550

gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);

544

551

545

552

return 0;

546

553

547

554

globalfail:

548

555

549

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_certificate_free_credentials(mc->cred);

550

557

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

558

gnutls_dh_params_deinit(mc->dh_params);

552

559

return -1;

553

560

}

554

561

555

static int init_gnutls_session(gnutls_session_t *session){

562

static int init_gnutls_session(gnutls_session_t *session,

563

mandos_context *mc){

556

564

int ret;

557

565

/* GnuTLS session creation */

558

566

do {

570

578

{

571

579

const char *err;

572

580

do {

573

ret = gnutls_priority_set_direct(*session, mc.priority, &err);

581

ret = gnutls_priority_set_direct(*session, mc->priority, &err);

574

582

if(quit_now){

575

583

gnutls_deinit(*session);

576

584

return -1;

587

595

588

596

do {

589

597

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

598

mc->cred);

591

599

if(quit_now){

592

600

gnutls_deinit(*session);

593

601

return -1;

603

611

/* ignore client certificate if any. */

604

612

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

613

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

614

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

607

615

608

616

return 0;

609

617

}

613

621

__attribute__((unused)) const char *txt){}

614

622

615

623

/* Called when a Mandos server is found */

616

static int start_mandos_communication(const char *ip, uint16_t port,

624

static int start_mandos_communication(const char *ip, in_port_t port,

617

625

AvahiIfIndex if_index,

618

int af){

626

int af, mandos_context *mc){

619

627

int ret, tcp_sd = -1;

620

628

ssize_t sret;

621

629

union {

651

659

return -1;

652

660

}

653

661

654

ret = init_gnutls_session(&session);

662

/* If the interface is specified and we have a list of interfaces */

663

if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){

664

/* Check if the interface is one of the interfaces we are using */

665

bool match = false;

666

{

667

char *interface = NULL;

668

while((interface=argz_next(mc->interfaces, mc->interfaces_size,

669

interface))){

670

if(if_nametoindex(interface) == (unsigned int)if_index){

671

match = true;

672

break;

673

}

674

}

675

}

676

if(not match){

677

/* This interface does not match any in the list, so we don't

678

connect to the server */

679

if(debug){

680

char interface[IF_NAMESIZE];

681

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

682

perror_plus("if_indextoname");

683

} else {

684

fprintf_plus(stderr, "Skipping server on non-used interface"

685

" \"%s\"\n",

686

if_indextoname((unsigned int)if_index,

687

interface));

688

}

689

}

690

return -1;

691

}

692

}

693

694

ret = init_gnutls_session(&session, mc);

655

695

if(ret != 0){

656

696

return -1;

657

697

}

658

698

659

699

if(debug){

660

700

fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"

661

PRIu16 "\n", ip, port);

701

PRIuMAX "\n", ip, (uintmax_t)port);

662

702

}

663

703

664

704

tcp_sd = socket(pf, SOCK_STREAM, 0);

695

735

goto mandos_end;

696

736

}

697

737

if(af == AF_INET6){

698

to.in6.sin6_port = htons(port); /* Spurious warnings from

699

-Wconversion and

700

-Wunreachable-code */

701

738

to.in6.sin6_port = htons(port);

739

#ifdef __GNUC__

740

#pragma GCC diagnostic push

741

#pragma GCC diagnostic ignored "-Wstrict-aliasing"

742

#endif

702

743

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and

704

-Wunreachable-code*/

744

(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */

745

#ifdef __GNUC__

746

#pragma GCC diagnostic pop

747

#endif

705

748

if(if_index == AVAHI_IF_UNSPEC){

706

749

fprintf_plus(stderr, "An IPv6 link-local address is"

707

750

" incomplete without a network interface\n");

712

755

to.in6.sin6_scope_id = (uint32_t)if_index;

713

756

}

714

757

} else {

715

to.in.sin_port = htons(port); /* Spurious warnings from

716

-Wconversion and

717

-Wunreachable-code */

758

to.in.sin_port = htons(port);

718

759

}

719

760

720

761

if(quit_now){

728

769

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

729

770

perror_plus("if_indextoname");

730

771

} else {

731

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16

732

"\n", ip, interface, port);

772

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX

773

"\n", ip, interface, (uintmax_t)port);

733

774

}

734

775

} else {

735

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

736

ip, port);

776

fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",

777

ip, (uintmax_t)port);

737

778

}

738

779

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

780

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

817

858

goto mandos_end;

818

859

}

819

860

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

861

/* This casting via intptr_t is to eliminate warning about casting

862

an int to a pointer type. This is exactly how the GnuTLS Guile

863

function "set-session-transport-fd!" does it. */

864

gnutls_transport_set_ptr(session,

865

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

866

823

867

if(quit_now){

824

868

errno = EINTR;

929

973

if(buffer_length > 0){

930

974

ssize_t decrypted_buffer_size;

931

975

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

976

&decrypted_buffer, mc);

933

977

if(decrypted_buffer_size >= 0){

934

978

935

979

written = 0;

996

1040

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1041

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1042

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1043

void* mc){

1044

if(r == NULL){

1045

return;

1046

}

1001

1047

1002

1048

/* Called whenever a service has been resolved successfully or

1003

1049

timed out */

1012

1058

fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "

1013

1059

"'%s' of type '%s' in domain '%s': %s\n", name, type,

1014

1060

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1061

avahi_strerror(avahi_server_errno

1062

(((mandos_context*)mc)->server)));

1016

1063

break;

1017

1064

1018

1065

case AVAHI_RESOLVER_FOUND:

1024

1071

PRIdMAX ") on port %" PRIu16 "\n", name,

1025

1072

host_name, ip, (intmax_t)interface, port);

1026

1073

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1074

int ret = start_mandos_communication(ip, (in_port_t)port,

1075

interface,

1076

avahi_proto_to_af(proto),

1077

mc);

1029

1078

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1079

avahi_simple_poll_quit(simple_poll);

1031

1080

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1081

if(not add_server(ip, (in_port_t)port, interface,

1082

avahi_proto_to_af(proto),

1083

&((mandos_context*)mc)->current_server)){

1084

fprintf_plus(stderr, "Failed to add server \"%s\" to server"

1085

" list\n", name);

1086

}

1034

1087

}

1035

1088

}

1036

1089

}

1046

1099

const char *domain,

1047

1100

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1101

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1102

void* mc){

1103

if(b == NULL){

1104

return;

1105

}

1051

1106

1052

1107

/* Called whenever a new services becomes available on the LAN or

1053

1108

is removed from the LAN */

1061

1116

case AVAHI_BROWSER_FAILURE:

1062

1117

1063

1118

fprintf_plus(stderr, "(Avahi browser) %s\n",

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1119

avahi_strerror(avahi_server_errno

1120

(((mandos_context*)mc)->server)));

1121

avahi_simple_poll_quit(simple_poll);

1066

1122

return;

1067

1123

1068

1124

case AVAHI_BROWSER_NEW:

1071

1127

the callback function is called the Avahi server will free the

1072

1128

resolver for us. */

1073

1129

1074

if(avahi_s_service_resolver_new(mc.server, interface, protocol,

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1130

if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,

1131

interface, protocol, name, type,

1132

domain, protocol, 0,

1133

resolve_callback, mc) == NULL)

1077

1134

fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"

1078

1135

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1136

avahi_strerror(avahi_server_errno

1137

(((mandos_context*)mc)->server)));

1080

1138

break;

1081

1139

1082

1140

case AVAHI_BROWSER_REMOVE:

1101

1159

signal_received = sig;

1102

1160

int old_errno = errno;

1103

1161

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1162

if(simple_poll != NULL){

1163

avahi_simple_poll_quit(simple_poll);

1106

1164

}

1107

1165

errno = old_errno;

1108

1166

}

1109

1167

1110

1168

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

1111

1169

int ret;

1170

error_t ret_errno;

1112

1171

1113

1172

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

1114

1173

if(s < 0){

1174

ret_errno = errno;

1115

1175

perror_plus("socket");

1176

errno = ret_errno;

1116

1177

return false;

1117

1178

}

1118

1179

strcpy(ifr->ifr_name, ifname);

1119

1180

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1181

if(ret == -1){

1121

1182

if(debug){

1183

ret_errno = errno;

1122

1184

perror_plus("ioctl SIOCGIFFLAGS");

1185

errno = ret_errno;

1123

1186

}

1124

1187

return false;

1125

1188

}

1194

1257

}

1195

1258

1196

1259

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

fprintf_plus(stderr, "Failed to get flags for interface "

1210

"\"%s\"\n", if_entry->d_name);

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

if(not (ifr.ifr_flags & IFF_UP)){

1217

if(debug){

1218

fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

if(not (ifr.ifr_flags & IFF_RUNNING)){

1226

if(debug){

1227

fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1260

* This function determines if a network interface is up.

1261

*/

1262

bool interface_is_up(const char *interface){

1263

struct ifreq ifr;

1264

if(not get_flags(interface, &ifr)){

1265

if(debug){

1266

fprintf_plus(stderr, "Failed to get flags for interface "

1267

"\"%s\"\n", interface);

1268

}

1269

return false;

1270

}

1271

1272

return (bool)(ifr.ifr_flags & IFF_UP);

1273

}

1274

1275

/*

1276

* This function determines if a network interface is running

1277

*/

1278

bool interface_is_running(const char *interface){

1279

struct ifreq ifr;

1280

if(not get_flags(interface, &ifr)){

1281

if(debug){

1282

fprintf_plus(stderr, "Failed to get flags for interface "

1283

"\"%s\"\n", interface);

1284

}

1285

return false;

1286

}

1287

1288

return (bool)(ifr.ifr_flags & IFF_RUNNING);

1237

1289

}

1238

1290

1239

1291

int notdotentries(const struct dirent *direntry){

1301

1353

}

1302

1354

return 0;

1303

1355

}

1356

if(debug){

1357

fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",

1358

direntry->d_name);

1359

}

1304

1360

return 1;

1305

1361

}

1306

1362

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1363

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1364

mandos_context *mc){

1308

1365

int ret;

1309

1366

struct timespec now;

1310

1367

struct timespec waited_time;

1311

1368

intmax_t block_time;

1312

1369

1313

1370

while(true){

1314

if(mc.current_server == NULL){

1371

if(mc->current_server == NULL){

1315

1372

if (debug){

1316

1373

fprintf_plus(stderr, "Wait until first server is found."

1317

1374

" No timeout!\n");

1331

1388

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

1332

1389

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

1333

1390

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

1391

- mc->current_server->last_seen.tv_sec);

1335

1392

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

1393

- mc->current_server->last_seen.tv_nsec);

1337

1394

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

1338

1395

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

1339

1396

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

1347

1404

}

1348

1405

1349

1406

if(block_time <= 0){

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

1407

ret = start_mandos_communication(mc->current_server->ip,

1408

mc->current_server->port,

1409

mc->current_server->if_index,

1410

mc->current_server->af, mc);

1354

1411

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

1412

avahi_simple_poll_quit(s);

1356

1413

return 0;

1357

1414

}

1358

1415

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

1416

&mc->current_server->last_seen);

1360

1417

if(ret == -1){

1361

1418

perror_plus("clock_gettime");

1362

1419

return -1;

1363

1420

}

1364

mc.current_server = mc.current_server->next;

1421

mc->current_server = mc->current_server->next;

1365

1422

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

1366

1423

servers, but don't block */

1367

1424

}

1376

1433

}

1377

1434

}

1378

1435

1436

/* Set effective uid to 0, return errno */

1437

error_t raise_privileges(void){

1438

error_t old_errno = errno;

1439

error_t ret_errno = 0;

1440

if(seteuid(0) == -1){

1441

ret_errno = errno;

1442

perror_plus("seteuid");

1443

}

1444

errno = old_errno;

1445

return ret_errno;

1446

}

1447

1448

/* Set effective and real user ID to 0. Return errno. */

1449

error_t raise_privileges_permanently(void){

1450

error_t old_errno = errno;

1451

error_t ret_errno = raise_privileges();

1452

if(ret_errno != 0){

1453

errno = old_errno;

1454

return ret_errno;

1455

}

1456

if(setuid(0) == -1){

1457

ret_errno = errno;

1458

perror_plus("seteuid");

1459

}

1460

errno = old_errno;

1461

return ret_errno;

1462

}

1463

1464

/* Set effective user ID to unprivileged saved user ID */

1465

error_t lower_privileges(void){

1466

error_t old_errno = errno;

1467

error_t ret_errno = 0;

1468

if(seteuid(uid) == -1){

1469

ret_errno = errno;

1470

perror_plus("seteuid");

1471

}

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

1476

/* Lower privileges permanently */

1477

error_t lower_privileges_permanently(void){

1478

error_t old_errno = errno;

1479

error_t ret_errno = 0;

1480

if(setuid(uid) == -1){

1481

ret_errno = errno;

1482

perror_plus("setuid");

1483

}

1484

errno = old_errno;

1485

return ret_errno;

1486

}

1487

1379

1488

bool run_network_hooks(const char *mode, const char *interface,

1380

1489

const float delay){

1381

1490

struct dirent **direntries;

1384

1493

int numhooks = scandir(hookdir, &direntries, runnable_hook,

1385

1494

alphasort);

1386

1495

if(numhooks == -1){

1387

perror_plus("scandir");

1496

if(errno == ENOENT){

1497

if(debug){

1498

fprintf_plus(stderr, "Network hook directory \"%s\" not"

1499

" found\n", hookdir);

1500

}

1501

} else {

1502

perror_plus("scandir");

1503

}

1388

1504

} else {

1389

1505

int devnull = open("/dev/null", O_RDONLY);

1390

1506

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

1391

direntry = direntries[0];

1507

direntry = direntries[i];

1392

1508

char *fullname = NULL;

1393

1509

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1394

1510

if(ret < 0){

1395

1511

perror_plus("asprintf");

1396

1512

continue;

1397

1513

}

1514

if(debug){

1515

fprintf_plus(stderr, "Running network hook \"%s\"\n",

1516

direntry->d_name);

1517

}

1398

1518

pid_t hook_pid = fork();

1399

1519

if(hook_pid == 0){

1400

1520

/* Child */

1521

/* Raise privileges */

1522

raise_privileges_permanently();

1523

/* Set group */

1524

errno = 0;

1525

ret = setgid(0);

1526

if(ret == -1){

1527

perror_plus("setgid");

1528

}

1529

/* Reset supplementary groups */

1530

errno = 0;

1531

ret = setgroups(0, NULL);

1532

if(ret == -1){

1533

perror_plus("setgroups");

1534

}

1401

1535

dup2(devnull, STDIN_FILENO);

1402

1536

close(devnull);

1403

1537

dup2(STDERR_FILENO, STDOUT_FILENO);

1404

1538

ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);

1405

1539

if(ret == -1){

1406

1540

perror_plus("setenv");

1407

return false;

1541

_exit(EX_OSERR);

1408

1542

}

1409

1543

ret = setenv("DEVICE", interface, 1);

1410

1544

if(ret == -1){

1411

1545

perror_plus("setenv");

1412

return false;

1546

_exit(EX_OSERR);

1413

1547

}

1414

ret = setenv("VERBOSE", debug ? "1" : "0", 1);

1548

ret = setenv("VERBOSITY", debug ? "1" : "0", 1);

1415

1549

if(ret == -1){

1416

1550

perror_plus("setenv");

1417

return false;

1551

_exit(EX_OSERR);

1418

1552

}

1419

1553

ret = setenv("MODE", mode, 1);

1420

1554

if(ret == -1){

1421

1555

perror_plus("setenv");

1422

return false;

1556

_exit(EX_OSERR);

1423

1557

}

1424

1558

char *delaystring;

1425

1559

ret = asprintf(&delaystring, "%f", delay);

1426

1560

if(ret == -1){

1427

1561

perror_plus("asprintf");

1428

return false;

1562

_exit(EX_OSERR);

1429

1563

}

1430

1564

ret = setenv("DELAY", delaystring, 1);

1431

1565

if(ret == -1){

1432

1566

free(delaystring);

1433

1567

perror_plus("setenv");

1434

return false;

1568

_exit(EX_OSERR);

1435

1569

}

1436

1570

free(delaystring);

1437

ret = execl(fullname, direntry->d_name, mode, NULL);

1438

perror_plus("execl");

1571

if(connect_to != NULL){

1572

ret = setenv("CONNECT", connect_to, 1);

1573

if(ret == -1){

1574

perror_plus("setenv");

1575

_exit(EX_OSERR);

1576

}

1577

}

1578

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1579

perror_plus("execl");

1580

_exit(EXIT_FAILURE);

1581

}

1439

1582

} else {

1440

1583

int status;

1441

1584

if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){

1465

1608

}

1466

1609

}

1467

1610

free(fullname);

1468

if(quit_now){

1469

break;

1611

if(debug){

1612

fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",

1613

direntry->d_name);

1470

1614

}

1471

1615

}

1472

1616

close(devnull);

1474

1618

return true;

1475

1619

}

1476

1620

1621

error_t bring_up_interface(const char *const interface,

1622

const float delay){

1623

int sd = -1;

1624

error_t old_errno = errno;

1625

error_t ret_errno = 0;

1626

int ret, ret_setflags;

1627

struct ifreq network;

1628

unsigned int if_index = if_nametoindex(interface);

1629

if(if_index == 0){

1630

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

1631

errno = old_errno;

1632

return ENXIO;

1633

}

1634

1635

if(quit_now){

1636

errno = old_errno;

1637

return EINTR;

1638

}

1639

1640

if(not interface_is_up(interface)){

1641

if(not get_flags(interface, &network) and debug){

1642

ret_errno = errno;

1643

fprintf_plus(stderr, "Failed to get flags for interface "

1644

"\"%s\"\n", interface);

1645

return ret_errno;

1646

}

1647

network.ifr_flags |= IFF_UP;

1648

1649

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1650

if(sd < 0){

1651

ret_errno = errno;

1652

perror_plus("socket");

1653

errno = old_errno;

1654

return ret_errno;

1655

}

1656

1657

if(quit_now){

1658

close(sd);

1659

errno = old_errno;

1660

return EINTR;

1661

}

1662

1663

if(debug){

1664

fprintf_plus(stderr, "Bringing up interface \"%s\"\n",

1665

interface);

1666

}

1667

1668

/* Raise priviliges */

1669

raise_privileges();

1670

1671

#ifdef __linux__

1672

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1673

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

1674

int ret_linux = klogctl(8, NULL, 5);

1675

bool restore_loglevel = true;

1676

if(ret_linux == -1){

1677

restore_loglevel = false;

1678

perror_plus("klogctl");

1679

}

1680

#endif /* __linux__ */

1681

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

1682

ret_errno = errno;

1683

#ifdef __linux__

1684

if(restore_loglevel){

1685

ret_linux = klogctl(7, NULL, 0);

1686

if(ret_linux == -1){

1687

perror_plus("klogctl");

1688

}

1689

}

1690

#endif /* __linux__ */

1691

1692

/* Lower privileges */

1693

lower_privileges();

1694

1695

/* Close the socket */

1696

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

1697

if(ret == -1){

1698

perror_plus("close");

1699

}

1700

1701

if(ret_setflags == -1){

1702

errno = ret_errno;

1703

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

} else if(debug){

1708

fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",

1709

interface);

1710

}

1711

1712

/* Sleep checking until interface is running.

1713

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

1714

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

1715

if(interface_is_running(interface)){

1716

break;

1717

}

1718

struct timespec sleeptime = { .tv_nsec = 250000000 };

1719

ret = nanosleep(&sleeptime, NULL);

1720

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

1721

perror_plus("nanosleep");

1722

}

1723

}

1724

1725

errno = old_errno;

1726

return 0;

1727

}

1728

1729

error_t take_down_interface(const char *const interface){

1730

int sd = -1;

1731

error_t old_errno = errno;

1732

error_t ret_errno = 0;

1733

int ret, ret_setflags;

1734

struct ifreq network;

1735

unsigned int if_index = if_nametoindex(interface);

1736

if(if_index == 0){

1737

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

1738

errno = old_errno;

1739

return ENXIO;

1740

}

1741

if(interface_is_up(interface)){

1742

if(not get_flags(interface, &network) and debug){

1743

ret_errno = errno;

1744

fprintf_plus(stderr, "Failed to get flags for interface "

1745

"\"%s\"\n", interface);

1746

return ret_errno;

1747

}

1748

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

1749

1750

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1751

if(sd < 0){

1752

ret_errno = errno;

1753

perror_plus("socket");

1754

errno = old_errno;

1755

return ret_errno;

1756

}

1757

1758

if(debug){

1759

fprintf_plus(stderr, "Taking down interface \"%s\"\n",

1760

interface);

1761

}

1762

1763

/* Raise priviliges */

1764

raise_privileges();

1765

1766

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

1767

ret_errno = errno;

1768

1769

/* Lower privileges */

1770

lower_privileges();

1771

1772

/* Close the socket */

1773

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

1774

if(ret == -1){

1775

perror_plus("close");

1776

}

1777

1778

if(ret_setflags == -1){

1779

errno = ret_errno;

1780

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1781

errno = old_errno;

1782

return ret_errno;

1783

}

1784

} else if(debug){

1785

fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",

1786

interface);

1787

}

1788

1789

errno = old_errno;

1790

return 0;

1791

}

1792

1477

1793

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

1794

mandos_context mc = { .server = NULL, .dh_bits = 1024,

1795

.priority = "SECURE256:!CTYPE-X.509:"

1796

"+CTYPE-OPENPGP", .current_server = NULL,

1797

.interfaces = NULL, .interfaces_size = 0 };

1478

1798

AvahiSServiceBrowser *sb = NULL;

1479

int error;

1799

error_t ret_errno;

1480

1800

int ret;

1481

1801

intmax_t tmpmax;

1482

1802

char *tmp;

1483

1803

int exitcode = EXIT_SUCCESS;

1484

const char *interface = "";

1485

struct ifreq network;

1486

int sd = -1;

1487

bool take_down_interface = false;

1488

uid_t uid;

1489

gid_t gid;

1804

char *interfaces_to_take_down = NULL;

1805

size_t interfaces_to_take_down_size = 0;

1490

1806

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

1491

1807

bool tempdir_created = false;

1492

1808

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1493

1809

const char *seckey = PATHDIR "/" SECKEY;

1494

1810

const char *pubkey = PATHDIR "/" PUBKEY;

1811

char *interfaces_hooks = NULL;

1812

size_t interfaces_hooks_size = 0;

1495

1813

1496

1814

bool gnutls_initialized = false;

1497

1815

bool gpgme_initialized = false;

1559

1877

.group = 2 },

1560

1878

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

1561

1879

.arg = "SECONDS",

1562

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

1880

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

1563

1881

.group = 2 },

1564

1882

{ .name = "network-hook-dir", .key = 133,

1565

1883

.arg = "DIR",

1588

1906

connect_to = arg;

1589

1907

break;

1590

1908

case 'i': /* --interface */

1591

interface = arg;

1909

ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,

1910

arg, (int)',');

1911

if(ret_errno != 0){

1912

argp_error(state, "%s", strerror(ret_errno));

1913

}

1592

1914

break;

1593

1915

case 's': /* --seckey */

1594

1916

seckey = arg;

1637

1959

argp_state_help(state, state->out_stream,

1638

1960

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1639

1961

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

1640

fprintf_plus(state->out_stream,

1641

"Mandos plugin mandos-client: ");

1642

1962

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

1643

1963

exit(argp_err_exit_status);

1644

1964

break;

1672

1992

{

1673

1993

/* Work around Debian bug #633582:

1674

1994

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

1675

struct stat st;

1676

1995

1677

1996

/* Re-raise priviliges */

1678

errno = 0;

1679

ret = seteuid(0);

1680

if(ret == -1){

1681

perror_plus("seteuid");

1682

}

1683

1684

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

1685

int seckey_fd = open(seckey, O_RDONLY);

1686

if(seckey_fd == -1){

1687

perror_plus("open");

1688

} else {

1689

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

1690

if(ret == -1){

1691

perror_plus("fstat");

1692

} else {

1693

if(S_ISREG(st.st_mode)

1694

and st.st_uid == 0 and st.st_gid == 0){

1695

ret = fchown(seckey_fd, uid, gid);

1696

if(ret == -1){

1697

perror_plus("fchown");

1698

}

1699

}

1700

}

1701

TEMP_FAILURE_RETRY(close(seckey_fd));

1702

}

1703

}

1704

1705

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

1706

int pubkey_fd = open(pubkey, O_RDONLY);

1707

if(pubkey_fd == -1){

1708

perror_plus("open");

1709

} else {

1710

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

1711

if(ret == -1){

1712

perror_plus("fstat");

1713

} else {

1714

if(S_ISREG(st.st_mode)

1715

and st.st_uid == 0 and st.st_gid == 0){

1716

ret = fchown(pubkey_fd, uid, gid);

1717

if(ret == -1){

1718

perror_plus("fchown");

1719

}

1720

}

1721

}

1722

TEMP_FAILURE_RETRY(close(pubkey_fd));

1723

}

1724

}

1725

1726

/* Lower privileges */

1727

errno = 0;

1728

ret = seteuid(uid);

1729

if(ret == -1){

1730

perror_plus("seteuid");

1997

if(raise_privileges() == 0){

1998

struct stat st;

1999

2000

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

2001

int seckey_fd = open(seckey, O_RDONLY);

2002

if(seckey_fd == -1){

2003

perror_plus("open");

2004

} else {

2005

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

2006

if(ret == -1){

2007

perror_plus("fstat");

2008

} else {

2009

if(S_ISREG(st.st_mode)

2010

and st.st_uid == 0 and st.st_gid == 0){

2011

ret = fchown(seckey_fd, uid, gid);

2012

if(ret == -1){

2013

perror_plus("fchown");

2014

}

2015

}

2016

}

2017

TEMP_FAILURE_RETRY(close(seckey_fd));

2018

}

2019

}

2020

2021

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

2022

int pubkey_fd = open(pubkey, O_RDONLY);

2023

if(pubkey_fd == -1){

2024

perror_plus("open");

2025

} else {

2026

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

2027

if(ret == -1){

2028

perror_plus("fstat");

2029

} else {

2030

if(S_ISREG(st.st_mode)

2031

and st.st_uid == 0 and st.st_gid == 0){

2032

ret = fchown(pubkey_fd, uid, gid);

2033

if(ret == -1){

2034

perror_plus("fchown");

2035

}

2036

}

2037

}

2038

TEMP_FAILURE_RETRY(close(pubkey_fd));

2039

}

2040

}

2041

2042

/* Lower privileges */

2043

lower_privileges();

2044

}

2045

}

2046

2047

/* Remove invalid interface names (except "none") */

2048

{

2049

char *interface = NULL;

2050

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2051

interface))){

2052

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

2053

and if_nametoindex(interface) == 0){

2054

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

2055

fprintf_plus(stderr, "Not using nonexisting interface"

2056

" \"%s\"\n", interface);

2057

}

2058

argz_delete(&mc.interfaces, &mc.interfaces_size, interface);

2059

interface = NULL;

2060

}

1731

2061

}

1732

2062

}

1733

2063

1734

2064

/* Run network hooks */

1735

2065

{

1736

/* Re-raise priviliges */

1737

errno = 0;

1738

ret = seteuid(0);

1739

if(ret == -1){

1740

perror_plus("seteuid");

2066

if(mc.interfaces != NULL){

2067

interfaces_hooks = malloc(mc.interfaces_size);

2068

if(interfaces_hooks == NULL){

2069

perror_plus("malloc");

2070

goto end;

2071

}

2072

memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);

2073

interfaces_hooks_size = mc.interfaces_size;

2074

argz_stringify(interfaces_hooks, interfaces_hooks_size,

2075

(int)',');

1741

2076

}

1742

if(not run_network_hooks("start", interface, delay)){

2077

if(not run_network_hooks("start", interfaces_hooks != NULL ?

2078

interfaces_hooks : "", delay)){

1743

2079

goto end;

1744

2080

}

1745

/* Lower privileges */

1746

errno = 0;

1747

ret = seteuid(uid);

1748

if(ret == -1){

1749

perror_plus("seteuid");

1750

}

1751

2081

}

1752

2082

1753

2083

if(not debug){

1754

2084

avahi_set_log_function(empty_log);

1755

2085

}

1756

2086

1757

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

1758

struct dirent **direntries;

1759

/* First look for interfaces that are up */

1760

ret = scandir(sys_class_net, &direntries, up_interface,

1761

alphasort);

1762

if(ret == 0){

1763

/* No up interfaces, look for any good interfaces */

1764

free(direntries);

1765

ret = scandir(sys_class_net, &direntries, good_interface,

1766

alphasort);

1767

}

1768

if(ret >= 1){

1769

/* Pick the first interface returned */

1770

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

1771

if(debug){

1772

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

1773

}

1774

if(interface == NULL){

1775

perror_plus("malloc");

1776

free(direntries);

1777

exitcode = EXIT_FAILURE;

1778

goto end;

1779

}

1780

free(direntries);

1781

} else {

1782

free(direntries);

1783

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

1784

exitcode = EXIT_FAILURE;

1785

goto end;

1786

}

1787

}

1788

1789

2087

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

1790

2088

from the signal handler */

1791

2089

/* Initialize the pseudo-RNG for Avahi */

1792

2090

srand((unsigned int) time(NULL));

1793

mc.simple_poll = avahi_simple_poll_new();

1794

if(mc.simple_poll == NULL){

2091

simple_poll = avahi_simple_poll_new();

2092

if(simple_poll == NULL){

1795

2093

fprintf_plus(stderr,

1796

2094

"Avahi: Failed to create simple poll object.\n");

1797

2095

exitcode = EX_UNAVAILABLE;

1861

2159

}

1862

2160

}

1863

2161

1864

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

1865

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

1866

if_index = (AvahiIfIndex) if_nametoindex(interface);

1867

if(if_index == 0){

1868

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

1869

exitcode = EX_UNAVAILABLE;

1870

goto end;

1871

}

1872

1873

if(quit_now){

1874

goto end;

1875

}

1876

1877

/* Re-raise priviliges */

1878

errno = 0;

1879

ret = seteuid(0);

1880

if(ret == -1){

1881

perror_plus("seteuid");

1882

}

1883

1884

#ifdef __linux__

1885

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1886

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

1887

ret = klogctl(8, NULL, 5);

1888

bool restore_loglevel = true;

1889

if(ret == -1){

1890

restore_loglevel = false;

1891

perror_plus("klogctl");

1892

}

1893

#endif /* __linux__ */

1894

1895

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1896

if(sd < 0){

1897

perror_plus("socket");

1898

exitcode = EX_OSERR;

1899

#ifdef __linux__

1900

if(restore_loglevel){

1901

ret = klogctl(7, NULL, 0);

1902

if(ret == -1){

1903

perror_plus("klogctl");

1904

}

1905

}

1906

#endif /* __linux__ */

1907

/* Lower privileges */

1908

errno = 0;

1909

ret = seteuid(uid);

1910

if(ret == -1){

1911

perror_plus("seteuid");

1912

}

1913

goto end;

1914

}

1915

strcpy(network.ifr_name, interface);

1916

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

1917

if(ret == -1){

1918

perror_plus("ioctl SIOCGIFFLAGS");

1919

#ifdef __linux__

1920

if(restore_loglevel){

1921

ret = klogctl(7, NULL, 0);

1922

if(ret == -1){

1923

perror_plus("klogctl");

1924

}

1925

}

1926

#endif /* __linux__ */

1927

exitcode = EX_OSERR;

1928

/* Lower privileges */

1929

errno = 0;

1930

ret = seteuid(uid);

1931

if(ret == -1){

1932

perror_plus("seteuid");

1933

}

1934

goto end;

1935

}

1936

if((network.ifr_flags & IFF_UP) == 0){

1937

network.ifr_flags |= IFF_UP;

1938

take_down_interface = true;

1939

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

1940

if(ret == -1){

1941

take_down_interface = false;

1942

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1943

exitcode = EX_OSERR;

1944

#ifdef __linux__

1945

if(restore_loglevel){

1946

ret = klogctl(7, NULL, 0);

1947

if(ret == -1){

1948

perror_plus("klogctl");

2162

/* If no interfaces were specified, make a list */

2163

if(mc.interfaces == NULL){

2164

struct dirent **direntries;

2165

/* Look for any good interfaces */

2166

ret = scandir(sys_class_net, &direntries, good_interface,

2167

alphasort);

2168

if(ret >= 1){

2169

/* Add all found interfaces to interfaces list */

2170

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

2171

ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,

2172

direntries[i]->d_name);

2173

if(ret_errno != 0){

2174

perror_plus("argz_add");

2175

continue;

2176

}

2177

if(debug){

2178

fprintf_plus(stderr, "Will use interface \"%s\"\n",

2179

direntries[i]->d_name);

2180

}

2181

}

2182

free(direntries);

2183

} else {

2184

free(direntries);

2185

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

2186

exitcode = EXIT_FAILURE;

2187

goto end;

2188

}

2189

}

2190

2191

/* Bring up interfaces which are down, and remove any "none"s */

2192

{

2193

char *interface = NULL;

2194

while((interface = argz_next(mc.interfaces, mc.interfaces_size,

2195

interface))){

2196

/* If interface name is "none", stop bringing up interfaces.

2197

Also remove all instances of "none" from the list */

2198

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

2199

argz_delete(&mc.interfaces, &mc.interfaces_size,

2200

interface);

2201

interface = NULL;

2202

while((interface = argz_next(mc.interfaces,

2203

mc.interfaces_size, interface))){

2204

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

2205

argz_delete(&mc.interfaces, &mc.interfaces_size,

2206

interface);

2207

interface = NULL;

1949

2208

}

1950

2209

}

1951

#endif /* __linux__ */

1952

/* Lower privileges */

1953

errno = 0;

1954

ret = seteuid(uid);

1955

if(ret == -1){

1956

perror_plus("seteuid");

1957

}

1958

goto end;

1959

}

1960

}

1961

/* Sleep checking until interface is running.

1962

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

1963

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

1964

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

1965

if(ret == -1){

1966

perror_plus("ioctl SIOCGIFFLAGS");

1967

} else if(network.ifr_flags & IFF_RUNNING){

1968

2210

break;

1969

2211

}

1970

struct timespec sleeptime = { .tv_nsec = 250000000 };

1971

ret = nanosleep(&sleeptime, NULL);

1972

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

1973

perror_plus("nanosleep");

1974

}

1975

}

1976

if(not take_down_interface){

1977

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

1978

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

1979

if(ret == -1){

1980

perror_plus("close");

1981

}

1982

}

1983

#ifdef __linux__

1984

if(restore_loglevel){

1985

/* Restores kernel loglevel to default */

1986

ret = klogctl(7, NULL, 0);

1987

if(ret == -1){

1988

perror_plus("klogctl");

1989

}

1990

}

1991

#endif /* __linux__ */

1992

/* Lower privileges */

1993

errno = 0;

1994

/* Lower privileges */

1995

ret = seteuid(uid);

1996

if(ret == -1){

1997

perror_plus("seteuid");

1998

}

2212

bool interface_was_up = interface_is_up(interface);

2213

ret = bring_up_interface(interface, delay);

2214

if(not interface_was_up){

2215

if(ret != 0){

2216

errno = ret;

2217

perror_plus("Failed to bring up interface");

2218

} else {

2219

ret_errno = argz_add(&interfaces_to_take_down,

2220

&interfaces_to_take_down_size,

2221

interface);

2222

}

2223

}

2224

}

2225

if(debug and (interfaces_to_take_down == NULL)){

2226

fprintf_plus(stderr, "No interfaces were brought up\n");

2227

}

2228

}

2229

2230

/* If we only got one interface, explicitly use only that one */

2231

if(argz_count(mc.interfaces, mc.interfaces_size) == 1){

2232

if(debug){

2233

fprintf_plus(stderr, "Using only interface \"%s\"\n",

2234

mc.interfaces);

2235

}

2236

if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);

1999

2237

}

2000

2238

2001

2239

if(quit_now){

2002

2240

goto end;

2003

2241

}

2004

2242

2005

ret = init_gnutls_global(pubkey, seckey);

2243

ret = init_gnutls_global(pubkey, seckey, &mc);

2006

2244

if(ret == -1){

2007

2245

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

2008

2246

exitcode = EX_UNAVAILABLE;

2025

2263

goto end;

2026

2264

}

2027

2265

2028

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

2266

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

2029

2267

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

2030

2268

exitcode = EX_UNAVAILABLE;

2031

2269

goto end;

2041

2279

/* Connect directly, do not use Zeroconf */

2042

2280

/* (Mainly meant for debugging) */

2043

2281

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

2282

2044

2283

if(address == NULL){

2045

2284

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

2046

2285

exitcode = EX_USAGE;

2051

2290

goto end;

2052

2291

}

2053

2292

2054

uint16_t port;

2293

in_port_t port;

2055

2294

errno = 0;

2056

2295

tmpmax = strtoimax(address+1, &tmp, 10);

2057

2296

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

2058

or tmpmax != (uint16_t)tmpmax){

2297

or tmpmax != (in_port_t)tmpmax){

2059

2298

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

2060

2299

exitcode = EX_USAGE;

2061

2300

goto end;

2062

2301

}

2063

2302

2064

2303

if(quit_now){

2065

2304

goto end;

2066

2305

}

2067

2306

2068

port = (uint16_t)tmpmax;

2307

port = (in_port_t)tmpmax;

2069

2308

*address = '\0';

2070

2309

/* Colon in address indicates IPv6 */

2071

2310

int af;

2087

2326

}

2088

2327

2089

2328

while(not quit_now){

2090

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

2329

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

2330

&mc);

2091

2331

if(quit_now or ret == 0){

2092

2332

break;

2093

2333

}

2095

2335

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

2096

2336

(int)retry_interval);

2097

2337

}

2098

sleep((int)retry_interval);

2338

sleep((unsigned int)retry_interval);

2099

2339

}

2100

2340

2101

2341

if (not quit_now){

2119

2359

config.publish_domain = 0;

2120

2360

2121

2361

/* Allocate a new server */

2122

mc.server = avahi_server_new(avahi_simple_poll_get

2123

(mc.simple_poll), &config, NULL,

2124

NULL, &error);

2362

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2363

&config, NULL, NULL, &ret_errno);

2125

2364

2126

2365

/* Free the Avahi configuration data */

2127

2366

avahi_server_config_free(&config);

2130

2369

/* Check if creating the Avahi server object succeeded */

2131

2370

if(mc.server == NULL){

2132

2371

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

2133

avahi_strerror(error));

2372

avahi_strerror(ret_errno));

2134

2373

exitcode = EX_UNAVAILABLE;

2135

2374

goto end;

2136

2375

}

2142

2381

/* Create the Avahi service browser */

2143

2382

sb = avahi_s_service_browser_new(mc.server, if_index,

2144

2383

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2145

NULL, 0, browse_callback, NULL);

2384

NULL, 0, browse_callback,

2385

(void *)&mc);

2146

2386

if(sb == NULL){

2147

2387

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

2148

2388

avahi_strerror(avahi_server_errno(mc.server)));

2160

2400

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

2161

2401

}

2162

2402

2163

ret = avahi_loop_with_timeout(mc.simple_poll,

2164

(int)(retry_interval * 1000));

2403

ret = avahi_loop_with_timeout(simple_poll,

2404

(int)(retry_interval * 1000), &mc);

2165

2405

if(debug){

2166

2406

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

2167

2407

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

2174

2414

}

2175

2415

2176

2416

/* Cleanup things */

2417

free(mc.interfaces);

2418

2177

2419

if(sb != NULL)

2178

2420

avahi_s_service_browser_free(sb);

2179

2421

2180

2422

if(mc.server != NULL)

2181

2423

avahi_server_free(mc.server);

2182

2424

2183

if(mc.simple_poll != NULL)

2184

avahi_simple_poll_free(mc.simple_poll);

2425

if(simple_poll != NULL)

2426

avahi_simple_poll_free(simple_poll);

2185

2427

2186

2428

if(gnutls_initialized){

2187

2429

gnutls_certificate_free_credentials(mc.cred);

2192

2434

if(gpgme_initialized){

2193

2435

gpgme_release(mc.ctx);

2194

2436

}

2195

2437

2196

2438

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

2197

2439

has seen */

2198

2440

if(mc.current_server != NULL){

2206

2448

2207

2449

/* Re-raise priviliges */

2208

2450

{

2209

errno = 0;

2210

ret = seteuid(0);

2211

if(ret == -1){

2212

perror_plus("seteuid");

2213

}

2451

raise_privileges();

2452

2214

2453

/* Run network hooks */

2215

if(not run_network_hooks("stop", interface, delay)){

2216

goto end;

2217

}

2454

run_network_hooks("stop", interfaces_hooks != NULL ?

2455

interfaces_hooks : "", delay);

2218

2456

2219

/* Take down the network interface */

2220

if(take_down_interface and geteuid() == 0){

2221

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

2222

if(ret == -1){

2223

perror_plus("ioctl SIOCGIFFLAGS");

2224

} else if(network.ifr_flags & IFF_UP){

2225

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

2226

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

2227

if(ret == -1){

2228

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2457

/* Take down the network interfaces which were brought up */

2458

{

2459

char *interface = NULL;

2460

while((interface=argz_next(interfaces_to_take_down,

2461

interfaces_to_take_down_size,

2462

interface))){

2463

ret_errno = take_down_interface(interface);

2464

if(ret_errno != 0){

2465

errno = ret_errno;

2466

perror_plus("Failed to take down interface");

2229

2467

}

2230

2468

}

2231

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

2232

if(ret == -1){

2233

perror_plus("close");

2469

if(debug and (interfaces_to_take_down == NULL)){

2470

fprintf_plus(stderr, "No interfaces needed to be taken"

2471

" down\n");

2234

2472

}

2235

2473

}

2236

}

2237

/* Lower privileges permanently */

2238

errno = 0;

2239

ret = setuid(uid);

2240

if(ret == -1){

2241

perror_plus("setuid");

2242

}

2474

2475

lower_privileges_permanently();

2476

}

2477

2478

free(interfaces_to_take_down);

2479

free(interfaces_hooks);

2243

2480

2244

2481

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

2245

2482

if(tempdir_created){