/mandos/release : revision 237.15.6

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* "browse_callback", and parts of "main".

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*

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* Everything else is

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*

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* This file is part of Mandos.

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*

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* Mandos is free software: you can redistribute it and/or modify it

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* under the terms of the GNU General Public License as published by

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* the Free Software Foundation, either version 3 of the License, or

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* (at your option) any later version.

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*

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* Mandos is distributed in the hope that it will be useful, but

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*

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* This program is free software: you can redistribute it and/or

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* modify it under the terms of the GNU General Public License as

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* published by the Free Software Foundation, either version 3 of the

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* License, or (at your option) any later version.

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*

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* This program is distributed in the hope that it will be useful, but

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

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* General Public License for more details.

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*

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* You should have received a copy of the GNU General Public License

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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

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* along with this program. If not, see

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* <http://www.gnu.org/licenses/>.

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*

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* Contact the authors at <mandos@recompile.se>.

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*/

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/* Needed by GPGME, specifically gpgme_data_seek() */

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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#include <sys/ioctl.h> /* ioctl */

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52

#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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#include <sys/stat.h> /* open(), S_ISREG */

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#include <sys/socket.h> /* socket(), struct sockaddr_in6,

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inet_pton(), connect(),

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getnameinfo() */

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#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */

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inet_pton(), connect() */

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#include <fcntl.h> /* open() */

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60

#include <dirent.h> /* opendir(), struct dirent, readdir()

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61

*/

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

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63

strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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

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

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program_invocation_short_name */

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

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

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73

*/

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74

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

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

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setgid(), pause(), _exit(),

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unlinkat() */

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

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setgid(), pause() */

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

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

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

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argp_state, struct argp,

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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134

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

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char *connect_to = NULL;

150

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

165

148

166

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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152

AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

172

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const char *priority;

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gpgme_ctx_t ctx;

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158

server *current_server;

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char *interfaces;

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size_t interfaces_size;

177

159

} mandos_context;

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160

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/* global so signal handler can reach it*/

180

AvahiSimplePoll *simple_poll;

161

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

162

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

181

166

182

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sig_atomic_t quit_now = 0;

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168

int signal_received = 0;

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169

185

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/* Function to use when printing errors */

186

171

void perror_plus(const char *print_text){

187

int e = errno;

188

172

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

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173

program_invocation_short_name);

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errno = e;

191

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perror(print_text);

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175

}

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194

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

195

177

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

196

178

va_list ap;

197

179

va_start (ap, format);

198

180

199

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

200

program_invocation_short_name));

201

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

181

TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ", program_invocation_short_name));

182

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

202

183

}

203

184

204

185

/*

206

187

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

207

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* "buffer_length" is how much is already used.

208

189

*/

209

__attribute__((nonnull, warn_unused_result))

210

190

size_t incbuffer(char **buffer, size_t buffer_length,

211

191

size_t buffer_capacity){

212

192

if(buffer_length + BUFFER_SIZE > buffer_capacity){

213

char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

214

if(new_buf == NULL){

215

int old_errno = errno;

216

free(*buffer);

217

errno = old_errno;

218

*buffer = NULL;

193

*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);

194

if(buffer == NULL){

219

195

return 0;

220

196

}

221

*buffer = new_buf;

222

197

buffer_capacity += BUFFER_SIZE;

223

198

}

224

199

return buffer_capacity;

225

200

}

226

201

227

202

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

228

__attribute__((nonnull, warn_unused_result))

229

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

230

int af, server **current_server){

203

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

204

int af){

231

205

int ret;

232

206

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

233

207

if(new_server == NULL){

234

208

perror_plus("malloc");

235

return false;

209

return -1;

236

210

}

237

211

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

238

212

.port = port,

240

214

.af = af };

241

215

if(new_server->ip == NULL){

242

216

perror_plus("strdup");

243

free(new_server);

244

return false;

245

}

246

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

249

#ifdef __GNUC__

250

#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

253

free((char *)(new_server->ip));

254

#ifdef __GNUC__

255

#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

return false;

217

return -1;

259

218

}

260

219

/* Special case of first server */

261

if(*current_server == NULL){

220

if (mc.current_server == NULL){

262

221

new_server->next = new_server;

263

222

new_server->prev = new_server;

264

*current_server = new_server;

223

mc.current_server = new_server;

224

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

265

225

} else {

266

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

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new_server->next = *current_server;

268

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

226

new_server->next = mc.current_server;

227

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

269

228

new_server->prev->next = new_server;

270

(*current_server)->prev = new_server;

271

}

272

return true;

229

mc.current_server->prev = new_server;

230

}

231

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

232

if(ret == -1){

233

perror_plus("clock_gettime");

234

return -1;

235

}

236

return 0;

273

237

}

274

238

275

239

/*

276

240

* Initialize GPGME.

277

241

*/

278

__attribute__((nonnull, warn_unused_result))

279

static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

281

const char * const tempdir,

282

mandos_context *mc){

242

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

243

const char *tempdir){

283

244

gpgme_error_t rc;

284

245

gpgme_engine_info_t engine_info;

285

246

247

286

248

/*

287

249

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

288

250

*/

289

bool import_key(const char * const filename){

251

bool import_key(const char *filename){

290

252

int ret;

291

253

int fd;

292

254

gpgme_data_t pgp_data;

300

262

rc = gpgme_data_new_from_fd(&pgp_data, fd);

301

263

if(rc != GPG_ERR_NO_ERROR){

302

264

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

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gpgme_strsource(rc), gpgme_strerror(rc));

265

gpgme_strsource(rc), gpgme_strerror(rc));

304

266

return false;

305

267

}

306

268

307

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

269

rc = gpgme_op_import(mc.ctx, pgp_data);

308

270

if(rc != GPG_ERR_NO_ERROR){

309

271

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

272

gpgme_strsource(rc), gpgme_strerror(rc));

311

273

return false;

312

274

}

313

275

314

ret = close(fd);

276

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

315

277

if(ret == -1){

316

278

perror_plus("close");

317

279

}

328

290

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

329

291

if(rc != GPG_ERR_NO_ERROR){

330

292

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

331

gpgme_strsource(rc), gpgme_strerror(rc));

293

gpgme_strsource(rc), gpgme_strerror(rc));

332

294

return false;

333

295

}

334

296

336

298

rc = gpgme_get_engine_info(&engine_info);

337

299

if(rc != GPG_ERR_NO_ERROR){

338

300

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

339

gpgme_strsource(rc), gpgme_strerror(rc));

301

gpgme_strsource(rc), gpgme_strerror(rc));

340

302

return false;

341

303

}

342

304

while(engine_info != NULL){

348

310

engine_info = engine_info->next;

349

311

}

350

312

if(engine_info == NULL){

351

fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",

352

tempdir);

313

fprintf_plus(stderr, "Could not set GPGME home dir to %s\n", tempdir);

353

314

return false;

354

315

}

355

316

356

317

/* Create new GPGME "context" */

357

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

318

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

358

319

if(rc != GPG_ERR_NO_ERROR){

359

320

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

360

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

361

gpgme_strerror(rc));

321

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

322

gpgme_strerror(rc));

362

323

return false;

363

324

}

364

325

373

334

* Decrypt OpenPGP data.

374

335

* Returns -1 on error

375

336

*/

376

__attribute__((nonnull, warn_unused_result))

377

337

static ssize_t pgp_packet_decrypt(const char *cryptotext,

378

338

size_t crypto_size,

379

char **plaintext,

380

mandos_context *mc){

339

char **plaintext){

381

340

gpgme_data_t dh_crypto, dh_plain;

382

341

gpgme_error_t rc;

383

342

ssize_t ret;

393

352

0);

394

353

if(rc != GPG_ERR_NO_ERROR){

395

354

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

396

gpgme_strsource(rc), gpgme_strerror(rc));

355

gpgme_strsource(rc), gpgme_strerror(rc));

397

356

return -1;

398

357

}

399

358

401

360

rc = gpgme_data_new(&dh_plain);

402

361

if(rc != GPG_ERR_NO_ERROR){

403

362

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

404

"bad gpgme_data_new: %s: %s\n",

405

gpgme_strsource(rc), gpgme_strerror(rc));

363

"bad gpgme_data_new: %s: %s\n",

364

gpgme_strsource(rc), gpgme_strerror(rc));

406

365

gpgme_data_release(dh_crypto);

407

366

return -1;

408

367

}

409

368

410

369

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

411

370

data buffer */

412

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

371

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

413

372

if(rc != GPG_ERR_NO_ERROR){

414

373

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

415

gpgme_strsource(rc), gpgme_strerror(rc));

374

gpgme_strsource(rc), gpgme_strerror(rc));

416

375

plaintext_length = -1;

417

376

if(debug){

418

377

gpgme_decrypt_result_t result;

419

result = gpgme_op_decrypt_result(mc->ctx);

378

result = gpgme_op_decrypt_result(mc.ctx);

420

379

if(result == NULL){

421

380

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

422

381

} else {

423

382

fprintf_plus(stderr, "Unsupported algorithm: %s\n",

424

result->unsupported_algorithm);

383

result->unsupported_algorithm);

425

384

fprintf_plus(stderr, "Wrong key usage: %u\n",

426

result->wrong_key_usage);

385

result->wrong_key_usage);

427

386

if(result->file_name != NULL){

428

387

fprintf_plus(stderr, "File name: %s\n", result->file_name);

429

388

}

431

390

recipient = result->recipients;

432

391

while(recipient != NULL){

433

392

fprintf_plus(stderr, "Public key algorithm: %s\n",

434

gpgme_pubkey_algo_name

435

(recipient->pubkey_algo));

393

gpgme_pubkey_algo_name(recipient->pubkey_algo));

436

394

fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);

437

395

fprintf_plus(stderr, "Secret key available: %s\n",

438

recipient->status == GPG_ERR_NO_SECKEY

439

? "No" : "Yes");

396

recipient->status == GPG_ERR_NO_SECKEY

397

? "No" : "Yes");

440

398

recipient = recipient->next;

441

399

}

442

400

}

499

457

return plaintext_length;

500

458

}

501

459

502

__attribute__((warn_unused_result, const))

503

static const char *safe_string(const char *str){

504

if(str == NULL)

505

return "(unknown)";

506

return str;

507

}

508

509

__attribute__((warn_unused_result))

510

static const char *safer_gnutls_strerror(int value){

511

const char *ret = gnutls_strerror(value);

512

return safe_string(ret);

460

static const char * safer_gnutls_strerror(int value){

461

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

462

-Wunreachable-code */

463

if(ret == NULL)

464

ret = "(unknown)";

465

return ret;

513

466

}

514

467

515

468

/* GnuTLS log function callback */

516

__attribute__((nonnull))

517

469

static void debuggnutls(__attribute__((unused)) int level,

518

470

const char* string){

519

471

fprintf_plus(stderr, "GnuTLS: %s", string);

520

472

}

521

473

522

__attribute__((nonnull(1, 2, 4), warn_unused_result))

523

474

static int init_gnutls_global(const char *pubkeyfilename,

524

const char *seckeyfilename,

525

const char *dhparamsfilename,

526

mandos_context *mc){

475

const char *seckeyfilename){

527

476

int ret;

528

unsigned int uret;

529

477

530

478

if(debug){

531

479

fprintf_plus(stderr, "Initializing GnuTLS\n");

532

480

}

533

481

482

ret = gnutls_global_init();

483

if(ret != GNUTLS_E_SUCCESS){

484

fprintf_plus(stderr, "GnuTLS global_init: %s\n", safer_gnutls_strerror(ret));

485

return -1;

486

}

487

534

488

if(debug){

535

489

/* "Use a log level over 10 to enable all debugging options."

536

490

* - GnuTLS manual

540

494

}

541

495

542

496

/* OpenPGP credentials */

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

497

ret = gnutls_certificate_allocate_credentials(&mc.cred);

544

498

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

499

fprintf_plus(stderr, "GnuTLS memory error: %s\n", safer_gnutls_strerror(ret));

500

gnutls_global_deinit();

547

501

return -1;

548

502

}

549

503

550

504

if(debug){

551

505

fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"

552

" secret key %s as GnuTLS credentials\n",

553

pubkeyfilename,

554

seckeyfilename);

506

" secret key %s as GnuTLS credentials\n", pubkeyfilename,

507

seckeyfilename);

555

508

}

556

509

557

510

ret = gnutls_certificate_set_openpgp_key_file

558

(mc->cred, pubkeyfilename, seckeyfilename,

511

(mc.cred, pubkeyfilename, seckeyfilename,

559

512

GNUTLS_OPENPGP_FMT_BASE64);

560

513

if(ret != GNUTLS_E_SUCCESS){

561

514

fprintf_plus(stderr,

562

515

"Error[%d] while reading the OpenPGP key pair ('%s',"

563

516

" '%s')\n", ret, pubkeyfilename, seckeyfilename);

564

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

565

safer_gnutls_strerror(ret));

517

fprintf_plus(stderr, "The GnuTLS error is: %s\n", safer_gnutls_strerror(ret));

566

518

goto globalfail;

567

519

}

568

520

569

521

/* GnuTLS server initialization */

570

ret = gnutls_dh_params_init(&mc->dh_params);

571

if(ret != GNUTLS_E_SUCCESS){

572

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

573

" initialization: %s\n",

574

safer_gnutls_strerror(ret));

575

goto globalfail;

576

}

577

/* If a Diffie-Hellman parameters file was given, try to use it */

578

if(dhparamsfilename != NULL){

579

gnutls_datum_t params = { .data = NULL, .size = 0 };

580

do {

581

int dhpfile = open(dhparamsfilename, O_RDONLY);

582

if(dhpfile == -1){

583

perror_plus("open");

584

dhparamsfilename = NULL;

585

break;

586

}

587

size_t params_capacity = 0;

588

while(true){

589

params_capacity = incbuffer((char **)&params.data,

590

(size_t)params.size,

591

(size_t)params_capacity);

592

if(params_capacity == 0){

593

perror_plus("incbuffer");

594

free(params.data);

595

params.data = NULL;

596

dhparamsfilename = NULL;

597

break;

598

}

599

ssize_t bytes_read = read(dhpfile,

600

params.data + params.size,

601

BUFFER_SIZE);

602

/* EOF */

603

if(bytes_read == 0){

604

break;

605

}

606

/* check bytes_read for failure */

607

if(bytes_read < 0){

608

perror_plus("read");

609

free(params.data);

610

params.data = NULL;

611

dhparamsfilename = NULL;

612

break;

613

}

614

params.size += (unsigned int)bytes_read;

615

}

616

if(params.data == NULL){

617

dhparamsfilename = NULL;

618

}

619

if(dhparamsfilename == NULL){

620

break;

621

}

622

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

623

GNUTLS_X509_FMT_PEM);

624

if(ret != GNUTLS_E_SUCCESS){

625

fprintf_plus(stderr, "Failed to parse DH parameters in file"

626

" \"%s\": %s\n", dhparamsfilename,

627

safer_gnutls_strerror(ret));

628

dhparamsfilename = NULL;

629

}

630

free(params.data);

631

} while(false);

632

}

633

if(dhparamsfilename == NULL){

634

if(mc->dh_bits == 0){

635

/* Find out the optimal number of DH bits */

636

/* Try to read the private key file */

637

gnutls_datum_t buffer = { .data = NULL, .size = 0 };

638

do {

639

int secfile = open(seckeyfilename, O_RDONLY);

640

if(secfile == -1){

641

perror_plus("open");

642

break;

643

}

644

size_t buffer_capacity = 0;

645

while(true){

646

buffer_capacity = incbuffer((char **)&buffer.data,

647

(size_t)buffer.size,

648

(size_t)buffer_capacity);

649

if(buffer_capacity == 0){

650

perror_plus("incbuffer");

651

free(buffer.data);

652

buffer.data = NULL;

653

break;

654

}

655

ssize_t bytes_read = read(secfile,

656

buffer.data + buffer.size,

657

BUFFER_SIZE);

658

/* EOF */

659

if(bytes_read == 0){

660

break;

661

}

662

/* check bytes_read for failure */

663

if(bytes_read < 0){

664

perror_plus("read");

665

free(buffer.data);

666

buffer.data = NULL;

667

break;

668

}

669

buffer.size += (unsigned int)bytes_read;

670

}

671

close(secfile);

672

} while(false);

673

/* If successful, use buffer to parse private key */

674

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

675

if(buffer.data != NULL){

676

{

677

gnutls_openpgp_privkey_t privkey = NULL;

678

ret = gnutls_openpgp_privkey_init(&privkey);

679

if(ret != GNUTLS_E_SUCCESS){

680

fprintf_plus(stderr, "Error initializing OpenPGP key"

681

" structure: %s",

682

safer_gnutls_strerror(ret));

683

free(buffer.data);

684

buffer.data = NULL;

685

} else {

686

ret = gnutls_openpgp_privkey_import

687

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

688

if(ret != GNUTLS_E_SUCCESS){

689

fprintf_plus(stderr, "Error importing OpenPGP key : %s",

690

safer_gnutls_strerror(ret));

691

privkey = NULL;

692

}

693

free(buffer.data);

694

buffer.data = NULL;

695

if(privkey != NULL){

696

/* Use private key to suggest an appropriate

697

sec_param */

698

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

699

gnutls_openpgp_privkey_deinit(privkey);

700

if(debug){

701

fprintf_plus(stderr, "This OpenPGP key implies using"

702

" a GnuTLS security parameter \"%s\".\n",

703

safe_string(gnutls_sec_param_get_name

704

(sec_param)));

705

}

706

}

707

}

708

}

709

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

710

/* Err on the side of caution */

711

sec_param = GNUTLS_SEC_PARAM_ULTRA;

712

if(debug){

713

fprintf_plus(stderr, "Falling back to security parameter"

714

" \"%s\"\n",

715

safe_string(gnutls_sec_param_get_name

716

(sec_param)));

717

}

718

}

719

}

720

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

721

if(uret != 0){

722

mc->dh_bits = uret;

723

if(debug){

724

fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"

725

" implies %u DH bits; using that.\n",

726

safe_string(gnutls_sec_param_get_name

727

(sec_param)),

728

mc->dh_bits);

729

}

730

} else {

731

fprintf_plus(stderr, "Failed to get implied number of DH"

732

" bits for security parameter \"%s\"): %s\n",

733

safe_string(gnutls_sec_param_get_name

734

(sec_param)),

735

safer_gnutls_strerror(ret));

736

goto globalfail;

737

}

738

} else if(debug){

739

fprintf_plus(stderr, "DH bits explicitly set to %u\n",

740

mc->dh_bits);

741

}

742

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

743

if(ret != GNUTLS_E_SUCCESS){

744

fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"

745

" bits): %s\n", mc->dh_bits,

746

safer_gnutls_strerror(ret));

747

goto globalfail;

748

}

749

}

750

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

522

ret = gnutls_dh_params_init(&mc.dh_params);

523

if(ret != GNUTLS_E_SUCCESS){

524

fprintf_plus(stderr, "Error in GnuTLS DH parameter initialization:"

525

" %s\n", safer_gnutls_strerror(ret));

526

goto globalfail;

527

}

528

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

529

if(ret != GNUTLS_E_SUCCESS){

530

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

531

safer_gnutls_strerror(ret));

532

goto globalfail;

533

}

534

535

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

751

536

752

537

return 0;

753

538

754

539

globalfail:

755

540

756

gnutls_certificate_free_credentials(mc->cred);

757

gnutls_dh_params_deinit(mc->dh_params);

541

gnutls_certificate_free_credentials(mc.cred);

542

gnutls_global_deinit();

543

gnutls_dh_params_deinit(mc.dh_params);

758

544

return -1;

759

545

}

760

546

761

__attribute__((nonnull, warn_unused_result))

762

static int init_gnutls_session(gnutls_session_t *session,

763

mandos_context *mc){

547

static int init_gnutls_session(gnutls_session_t *session){

764

548

int ret;

765

549

/* GnuTLS session creation */

766

550

do {

770

554

}

771

555

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

772

556

if(ret != GNUTLS_E_SUCCESS){

773

fprintf_plus(stderr,

774

"Error in GnuTLS session initialization: %s\n",

775

safer_gnutls_strerror(ret));

557

fprintf_plus(stderr, "Error in GnuTLS session initialization: %s\n",

558

safer_gnutls_strerror(ret));

776

559

}

777

560

778

561

{

779

562

const char *err;

780

563

do {

781

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

564

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

782

565

if(quit_now){

783

566

gnutls_deinit(*session);

784

567

return -1;

786

569

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

787

570

if(ret != GNUTLS_E_SUCCESS){

788

571

fprintf_plus(stderr, "Syntax error at: %s\n", err);

789

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

790

safer_gnutls_strerror(ret));

572

fprintf_plus(stderr, "GnuTLS error: %s\n", safer_gnutls_strerror(ret));

791

573

gnutls_deinit(*session);

792

574

return -1;

793

575

}

795

577

796

578

do {

797

579

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

798

mc->cred);

580

mc.cred);

799

581

if(quit_now){

800

582

gnutls_deinit(*session);

801

583

return -1;

803

585

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

804

586

if(ret != GNUTLS_E_SUCCESS){

805

587

fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",

806

safer_gnutls_strerror(ret));

588

safer_gnutls_strerror(ret));

807

589

gnutls_deinit(*session);

808

590

return -1;

809

591

}

811

593

/* ignore client certificate if any. */

812

594

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

813

595

596

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

597

814

598

return 0;

815

599

}

816

600

818

602

static void empty_log(__attribute__((unused)) AvahiLogLevel level,

819

603

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

820

604

821

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

822

__attribute__((warn_unused_result))

823

int raise_privileges(void){

824

int old_errno = errno;

825

int ret = 0;

826

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

827

ret = errno;

828

}

829

errno = old_errno;

830

return ret;

831

}

832

833

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

834

__attribute__((warn_unused_result))

835

int raise_privileges_permanently(void){

836

int old_errno = errno;

837

int ret = raise_privileges();

838

if(ret != 0){

839

errno = old_errno;

840

return ret;

841

}

842

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

843

ret = errno;

844

}

845

errno = old_errno;

846

return ret;

847

}

848

849

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

850

__attribute__((warn_unused_result))

851

int lower_privileges(void){

852

int old_errno = errno;

853

int ret = 0;

854

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

855

ret = errno;

856

}

857

errno = old_errno;

858

return ret;

859

}

860

861

/* Lower privileges permanently */

862

__attribute__((warn_unused_result))

863

int lower_privileges_permanently(void){

864

int old_errno = errno;

865

int ret = 0;

866

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

867

ret = errno;

868

}

869

errno = old_errno;

870

return ret;

871

}

872

873

/* Helper function to add_local_route() and delete_local_route() */

874

__attribute__((nonnull, warn_unused_result))

875

static bool add_delete_local_route(const bool add,

876

const char *address,

877

AvahiIfIndex if_index){

878

int ret;

879

char helper[] = "mandos-client-iprouteadddel";

880

char add_arg[] = "add";

881

char delete_arg[] = "delete";

882

char debug_flag[] = "--debug";

883

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

884

if(pluginhelperdir == NULL){

885

if(debug){

886

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

887

" variable not set; cannot run helper\n");

888

}

889

return false;

890

}

891

892

char interface[IF_NAMESIZE];

893

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

894

perror_plus("if_indextoname");

895

return false;

896

}

897

898

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

899

if(devnull == -1){

900

perror_plus("open(\"/dev/null\", O_RDONLY)");

901

return false;

902

}

903

pid_t pid = fork();

904

if(pid == 0){

905

/* Child */

906

/* Raise privileges */

907

errno = raise_privileges_permanently();

908

if(errno != 0){

909

perror_plus("Failed to raise privileges");

910

/* _exit(EX_NOPERM); */

911

} else {

912

/* Set group */

913

errno = 0;

914

ret = setgid(0);

915

if(ret == -1){

916

perror_plus("setgid");

917

_exit(EX_NOPERM);

918

}

919

/* Reset supplementary groups */

920

errno = 0;

921

ret = setgroups(0, NULL);

922

if(ret == -1){

923

perror_plus("setgroups");

924

_exit(EX_NOPERM);

925

}

926

}

927

ret = dup2(devnull, STDIN_FILENO);

928

if(ret == -1){

929

perror_plus("dup2(devnull, STDIN_FILENO)");

930

_exit(EX_OSERR);

931

}

932

ret = close(devnull);

933

if(ret == -1){

934

perror_plus("close");

935

_exit(EX_OSERR);

936

}

937

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

938

if(ret == -1){

939

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

940

_exit(EX_OSERR);

941

}

942

int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,

943

O_RDONLY

944

| O_DIRECTORY

945

| O_PATH

946

| O_CLOEXEC));

947

if(helperdir_fd == -1){

948

perror_plus("open");

949

_exit(EX_UNAVAILABLE);

950

}

951

int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,

952

helper, O_RDONLY));

953

if(helper_fd == -1){

954

perror_plus("openat");

955

close(helperdir_fd);

956

_exit(EX_UNAVAILABLE);

957

}

958

close(helperdir_fd);

959

#ifdef __GNUC__

960

#pragma GCC diagnostic push

961

#pragma GCC diagnostic ignored "-Wcast-qual"

962

#endif

963

if(fexecve(helper_fd, (char *const [])

964

{ helper, add ? add_arg : delete_arg, (char *)address,

965

interface, debug ? debug_flag : NULL, NULL },

966

environ) == -1){

967

#ifdef __GNUC__

968

#pragma GCC diagnostic pop

969

#endif

970

perror_plus("fexecve");

971

_exit(EXIT_FAILURE);

972

}

973

}

974

if(pid == -1){

975

perror_plus("fork");

976

return false;

977

}

978

int status;

979

pid_t pret = -1;

980

errno = 0;

981

do {

982

pret = waitpid(pid, &status, 0);

983

if(pret == -1 and errno == EINTR and quit_now){

984

int errno_raising = 0;

985

if((errno = raise_privileges()) != 0){

986

errno_raising = errno;

987

perror_plus("Failed to raise privileges in order to"

988

" kill helper program");

989

}

990

if(kill(pid, SIGTERM) == -1){

991

perror_plus("kill");

992

}

993

if((errno_raising == 0) and (errno = lower_privileges()) != 0){

994

perror_plus("Failed to lower privileges after killing"

995

" helper program");

996

}

997

return false;

998

}

999

} while(pret == -1 and errno == EINTR);

1000

if(pret == -1){

1001

perror_plus("waitpid");

1002

return false;

1003

}

1004

if(WIFEXITED(status)){

1005

if(WEXITSTATUS(status) != 0){

1006

fprintf_plus(stderr, "Error: iprouteadddel exited"

1007

" with status %d\n", WEXITSTATUS(status));

1008

return false;

1009

}

1010

return true;

1011

}

1012

if(WIFSIGNALED(status)){

1013

fprintf_plus(stderr, "Error: iprouteadddel died by"

1014

" signal %d\n", WTERMSIG(status));

1015

return false;

1016

}

1017

fprintf_plus(stderr, "Error: iprouteadddel crashed\n");

1018

return false;

1019

}

1020

1021

__attribute__((nonnull, warn_unused_result))

1022

static bool add_local_route(const char *address,

1023

AvahiIfIndex if_index){

1024

if(debug){

1025

fprintf_plus(stderr, "Adding route to %s\n", address);

1026

}

1027

return add_delete_local_route(true, address, if_index);

1028

}

1029

1030

__attribute__((nonnull, warn_unused_result))

1031

static bool delete_local_route(const char *address,

1032

AvahiIfIndex if_index){

1033

if(debug){

1034

fprintf_plus(stderr, "Removing route to %s\n", address);

1035

}

1036

return add_delete_local_route(false, address, if_index);

1037

}

1038

1039

605

/* Called when a Mandos server is found */

1040

__attribute__((nonnull, warn_unused_result))

1041

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

606

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

1042

607

AvahiIfIndex if_index,

1043

int af, mandos_context *mc){

608

int af){

1044

609

int ret, tcp_sd = -1;

1045

610

ssize_t sret;

1046

struct sockaddr_storage to;

611

union {

612

struct sockaddr_in in;

613

struct sockaddr_in6 in6;

614

} to;

1047

615

char *buffer = NULL;

1048

616

char *decrypted_buffer = NULL;

1049

617

size_t buffer_length = 0;

1052

620

int retval = -1;

1053

621

gnutls_session_t session;

1054

622

int pf; /* Protocol family */

1055

bool route_added = false;

1056

623

1057

624

errno = 0;

1058

625

1074

641

return -1;

1075

642

}

1076

643

1077

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

1078

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

1079

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

1080

bool match = false;

1081

{

1082

char *interface = NULL;

1083

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

1084

mc->interfaces_size,

1085

interface))){

1086

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

1087

match = true;

1088

break;

1089

}

1090

}

1091

}

1092

if(not match){

1093

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

1094

connect to the server */

1095

if(debug){

1096

char interface[IF_NAMESIZE];

1097

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

1098

perror_plus("if_indextoname");

1099

} else {

1100

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

1101

" \"%s\"\n",

1102

if_indextoname((unsigned int)if_index,

1103

interface));

1104

}

1105

}

1106

return -1;

1107

}

1108

}

1109

1110

ret = init_gnutls_session(&session, mc);

644

ret = init_gnutls_session(&session);

1111

645

if(ret != 0){

1112

646

return -1;

1113

647

}

1114

648

1115

649

if(debug){

1116

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

1117

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

650

fprintf_plus(stderr, "Setting up a TCP connection to %s, port %" PRIu16

651

"\n", ip, port);

1118

652

}

1119

653

1120

tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);

654

tcp_sd = socket(pf, SOCK_STREAM, 0);

1121

655

if(tcp_sd < 0){

1122

656

int e = errno;

1123

657

perror_plus("socket");

1130

664

goto mandos_end;

1131

665

}

1132

666

667

memset(&to, 0, sizeof(to));

1133

668

if(af == AF_INET6){

1134

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1135

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1136

ret = inet_pton(af, ip, &to6->sin6_addr);

669

to.in6.sin6_family = (sa_family_t)af;

670

ret = inet_pton(af, ip, &to.in6.sin6_addr);

1137

671

} else { /* IPv4 */

1138

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1139

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1140

ret = inet_pton(af, ip, &to4->sin_addr);

672

to.in.sin_family = (sa_family_t)af;

673

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

1141

674

}

1142

675

if(ret < 0 ){

1143

676

int e = errno;

1152

685

goto mandos_end;

1153

686

}

1154

687

if(af == AF_INET6){

1155

((struct sockaddr_in6 *)&to)->sin6_port = htons(port);

1156

if(IN6_IS_ADDR_LINKLOCAL

1157

(&((struct sockaddr_in6 *)&to)->sin6_addr)){

688

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

689

-Wconversion and

690

-Wunreachable-code */

691

692

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

693

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

694

-Wunreachable-code*/

1158

695

if(if_index == AVAHI_IF_UNSPEC){

1159

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

1160

" incomplete without a network interface\n");

696

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

697

" without a network interface\n");

1161

698

errno = EINVAL;

1162

699

goto mandos_end;

1163

700

}

1164

701

/* Set the network interface number as scope */

1165

((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;

702

to.in6.sin6_scope_id = (uint32_t)if_index;

1166

703

}

1167

704

} else {

1168

((struct sockaddr_in *)&to)->sin_port = htons(port);

705

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

706

-Wconversion and

707

-Wunreachable-code */

1169

708

}

1170

709

1171

710

if(quit_now){

1179

718

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

1180

719

perror_plus("if_indextoname");

1181

720

} else {

1182

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

1183

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

721

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

722

ip, interface, port);

1184

723

}

1185

724

} else {

1186

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

1187

ip, (uintmax_t)port);

725

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

1188

726

}

1189

727

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1190

728

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1191

if(af == AF_INET6){

1192

ret = getnameinfo((struct sockaddr *)&to,

1193

sizeof(struct sockaddr_in6),

1194

addrstr, sizeof(addrstr), NULL, 0,

1195

NI_NUMERICHOST);

1196

} else {

1197

ret = getnameinfo((struct sockaddr *)&to,

1198

sizeof(struct sockaddr_in),

1199

addrstr, sizeof(addrstr), NULL, 0,

1200

NI_NUMERICHOST);

1201

}

1202

if(ret == EAI_SYSTEM){

1203

perror_plus("getnameinfo");

1204

} else if(ret != 0) {

1205

fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));

1206

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

1207

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

1208

}

1209

}

1210

1211

if(quit_now){

1212

errno = EINTR;

1213

goto mandos_end;

1214

}

1215

1216

while(true){

1217

if(af == AF_INET6){

1218

ret = connect(tcp_sd, (struct sockaddr *)&to,

1219

sizeof(struct sockaddr_in6));

1220

} else {

1221

ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */

1222

sizeof(struct sockaddr_in));

1223

}

1224

if(ret < 0){

1225

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1226

and if_index != AVAHI_IF_UNSPEC

1227

and connect_to == NULL

1228

and not route_added and

1229

((af == AF_INET6 and not

1230

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1231

&to)->sin6_addr)))

1232

or (af == AF_INET and

1233

/* Not a a IPv4LL address */

1234

(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)

1235

& 0xFFFF0000L) != 0xA9FE0000L))){

1236

/* Work around Avahi bug - Avahi does not announce link-local

1237

addresses if it has a global address, so local hosts with

1238

*only* a link-local address (e.g. Mandos clients) cannot

1239

connect to a Mandos server announced by Avahi on a server

1240

host with a global address. Work around this by retrying

1241

with an explicit route added with the server's address.

1242

1243

Avahi bug reference:

1244

https://lists.freedesktop.org/archives/avahi/2010-February/001833.html

1245

https://bugs.debian.org/587961

1246

*/

1247

if(debug){

1248

fprintf_plus(stderr, "Mandos server unreachable, trying"

1249

" direct route\n");

1250

}

1251

int e = errno;

1252

route_added = add_local_route(ip, if_index);

1253

if(route_added){

1254

continue;

1255

}

1256

errno = e;

1257

}

1258

if(errno != ECONNREFUSED or debug){

1259

int e = errno;

1260

perror_plus("connect");

1261

errno = e;

1262

}

1263

goto mandos_end;

1264

}

1265

1266

if(quit_now){

1267

errno = EINTR;

1268

goto mandos_end;

1269

}

1270

break;

729

const char *pcret;

730

if(af == AF_INET6){

731

pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,

732

sizeof(addrstr));

733

} else {

734

pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,

735

sizeof(addrstr));

736

}

737

if(pcret == NULL){

738

perror_plus("inet_ntop");

739

} else {

740

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

741

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

742

}

743

}

744

}

745

746

if(quit_now){

747

errno = EINTR;

748

goto mandos_end;

749

}

750

751

if(af == AF_INET6){

752

ret = connect(tcp_sd, &to.in6, sizeof(to));

753

} else {

754

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

755

}

756

if(ret < 0){

757

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

758

int e = errno;

759

perror_plus("connect");

760

errno = e;

761

}

762

goto mandos_end;

763

}

764

765

if(quit_now){

766

errno = EINTR;

767

goto mandos_end;

1271

768

}

1272

769

1273

770

const char *out = mandos_protocol_version;

1309

806

goto mandos_end;

1310

807

}

1311

808

1312

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

1313

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

1314

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

1315

gnutls_transport_set_ptr(session,

1316

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

809

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

810

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1317

811

1318

812

if(quit_now){

1319

813

errno = EINTR;

1340

834

/* Read OpenPGP packet that contains the wanted password */

1341

835

1342

836

if(debug){

1343

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1344

" %s\n", ip);

837

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from %s\n", ip);

1345

838

}

1346

839

1347

840

while(true){

1385

878

}

1386

879

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

1387

880

if(ret < 0){

1388

fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "

1389

"***\n");

881

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

1390

882

gnutls_perror(ret);

1391

883

errno = EPROTO;

1392

884

goto mandos_end;

1394

886

break;

1395

887

default:

1396

888

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

1397

" encrypted session with Mandos server\n");

889

" encrypted session with Mandos server\n");

1398

890

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1399

891

errno = EIO;

1400

892

goto mandos_end;

1424

916

if(buffer_length > 0){

1425

917

ssize_t decrypted_buffer_size;

1426

918

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1427

&decrypted_buffer, mc);

919

&decrypted_buffer);

1428

920

if(decrypted_buffer_size >= 0){

1429

921

1430

clearerr(stdout);

1431

922

written = 0;

1432

923

while(written < (size_t) decrypted_buffer_size){

1433

924

if(quit_now){

1442

933

int e = errno;

1443

934

if(debug){

1444

935

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

1445

strerror(errno));

936

strerror(errno));

1446

937

}

1447

938

errno = e;

1448

939

goto mandos_end;

1449

940

}

1450

941

written += (size_t)ret;

1451

942

}

1452

ret = fflush(stdout);

1453

if(ret != 0){

1454

int e = errno;

1455

if(debug){

1456

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

1457

strerror(errno));

1458

}

1459

errno = e;

1460

goto mandos_end;

1461

}

1462

943

retval = 0;

1463

944

}

1464

945

}

1467

948

1468

949

mandos_end:

1469

950

{

1470

if(route_added){

1471

if(not delete_local_route(ip, if_index)){

1472

fprintf_plus(stderr, "Failed to delete local route to %s on"

1473

" interface %d", ip, if_index);

1474

}

1475

}

1476

951

int e = errno;

1477

952

free(decrypted_buffer);

1478

953

free(buffer);

1479

954

if(tcp_sd >= 0){

1480

ret = close(tcp_sd);

955

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

1481

956

}

1482

957

if(ret == -1){

1483

958

if(e == 0){

1508

983

AVAHI_GCC_UNUSED AvahiStringList *txt,

1509

984

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1510

985

flags,

1511

void *mc){

1512

if(r == NULL){

1513

return;

1514

}

986

AVAHI_GCC_UNUSED void* userdata){

987

assert(r);

1515

988

1516

989

/* Called whenever a service has been resolved successfully or

1517

990

timed out */

1518

991

1519

992

if(quit_now){

1520

avahi_s_service_resolver_free(r);

1521

993

return;

1522

994

}

1523

995

1524

996

switch(event){

1525

997

default:

1526

998

case AVAHI_RESOLVER_FAILURE:

1527

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

1528

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

1529

domain,

1530

avahi_strerror(avahi_server_errno

1531

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

999

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

1000

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

1001

avahi_strerror(avahi_server_errno(mc.server)));

1532

1002

break;

1533

1003

1534

1004

case AVAHI_RESOLVER_FOUND:

1537

1007

avahi_address_snprint(ip, sizeof(ip), address);

1538

1008

if(debug){

1539

1009

fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"

1540

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

1541

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

1010

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

1011

ip, (intmax_t)interface, port);

1542

1012

}

1543

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

1544

interface,

1545

avahi_proto_to_af(proto),

1546

mc);

1013

int ret = start_mandos_communication(ip, port, interface,

1014

avahi_proto_to_af(proto));

1547

1015

if(ret == 0){

1548

avahi_simple_poll_quit(simple_poll);

1016

avahi_simple_poll_quit(mc.simple_poll);

1549

1017

} else {

1550

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

1551

avahi_proto_to_af(proto),

1552

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

1553

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

1554

" list\n", name);

1555

}

1018

ret = add_server(ip, port, interface,

1019

avahi_proto_to_af(proto));

1556

1020

}

1557

1021

}

1558

1022

}

1568

1032

const char *domain,

1569

1033

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1570

1034

flags,

1571

void *mc){

1572

if(b == NULL){

1573

return;

1574

}

1035

AVAHI_GCC_UNUSED void* userdata){

1036

assert(b);

1575

1037

1576

1038

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

1577

1039

is removed from the LAN */

1585

1047

case AVAHI_BROWSER_FAILURE:

1586

1048

1587

1049

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

1588

avahi_strerror(avahi_server_errno

1589

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

1590

avahi_simple_poll_quit(simple_poll);

1050

avahi_strerror(avahi_server_errno(mc.server)));

1051

avahi_simple_poll_quit(mc.simple_poll);

1591

1052

return;

1592

1053

1593

1054

case AVAHI_BROWSER_NEW:

1596

1057

the callback function is called the Avahi server will free the

1597

1058

resolver for us. */

1598

1059

1599

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

1600

interface, protocol, name, type,

1601

domain, protocol, 0,

1602

resolve_callback, mc) == NULL)

1603

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

1604

" %s\n", name,

1605

avahi_strerror(avahi_server_errno

1606

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

1060

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

1061

name, type, domain, protocol, 0,

1062

resolve_callback, NULL) == NULL)

1063

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

1064

name, avahi_strerror(avahi_server_errno(mc.server)));

1607

1065

break;

1608

1066

1609

1067

case AVAHI_BROWSER_REMOVE:

1612

1070

case AVAHI_BROWSER_ALL_FOR_NOW:

1613

1071

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1614

1072

if(debug){

1615

fprintf_plus(stderr, "No Mandos server found, still"

1616

" searching...\n");

1073

fprintf_plus(stderr, "No Mandos server found, still searching...\n");

1617

1074

}

1618

1075

break;

1619

1076

}

1628

1085

signal_received = sig;

1629

1086

int old_errno = errno;

1630

1087

/* set main loop to exit */

1631

if(simple_poll != NULL){

1632

avahi_simple_poll_quit(simple_poll);

1088

if(mc.simple_poll != NULL){

1089

avahi_simple_poll_quit(mc.simple_poll);

1633

1090

}

1634

1091

errno = old_errno;

1635

1092

}

1636

1093

1637

__attribute__((nonnull, warn_unused_result))

1638

1094

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

1639

1095

int ret;

1640

int old_errno;

1641

1096

1642

1097

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

1643

1098

if(s < 0){

1644

old_errno = errno;

1645

1099

perror_plus("socket");

1646

errno = old_errno;

1647

1100

return false;

1648

1101

}

1649

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1650

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1102

strcpy(ifr->ifr_name, ifname);

1651

1103

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1652

1104

if(ret == -1){

1653

1105

if(debug){

1654

old_errno = errno;

1655

1106

perror_plus("ioctl SIOCGIFFLAGS");

1656

errno = old_errno;

1657

1107

}

1658

1108

return false;

1659

1109

}

1660

1110

return true;

1661

1111

}

1662

1112

1663

__attribute__((nonnull, warn_unused_result))

1664

1113

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

1665

1114

1666

1115

/* Reject the loopback device */

1667

1116

if(ifr->ifr_flags & IFF_LOOPBACK){

1668

1117

if(debug){

1669

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

1670

ifname);

1118

fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n", ifname);

1671

1119

}

1672

1120

return false;

1673

1121

}

1674

1122

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

1675

1123

if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){

1676

1124

if(debug){

1677

fprintf_plus(stderr, "Accepting point-to-point interface"

1678

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

1125

fprintf_plus(stderr, "Accepting point-to-point interface \"%s\"\n", ifname);

1679

1126

}

1680

1127

return true;

1681

1128

}

1682

1129

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

1683

1130

if(not (ifr->ifr_flags & IFF_BROADCAST)){

1684

1131

if(debug){

1685

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1686

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

1132

fprintf_plus(stderr, "Rejecting non-broadcast interface \"%s\"\n", ifname);

1687

1133

}

1688

1134

return false;

1689

1135

}

1690

1136

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

1691

1137

if(ifr->ifr_flags & IFF_NOARP){

1692

1138

if(debug){

1693

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

1694

ifname);

1139

fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n", ifname);

1695

1140

}

1696

1141

return false;

1697

1142

}

1708

1153

* corresponds to an acceptable network device.

1709

1154

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

1710

1155

*/

1711

__attribute__((nonnull, warn_unused_result))

1712

1156

int good_interface(const struct dirent *if_entry){

1713

1157

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

1714

1158

return 0;

1717

1161

struct ifreq ifr;

1718

1162

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

1719

1163

if(debug){

1720

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

1721

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

1722

}

1723

return 0;

1724

}

1725

1726

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

1727

return 0;

1728

}

1729

return 1;

1730

}

1731

1732

/*

1733

* This function determines if a network interface is up.

1734

*/

1735

__attribute__((nonnull, warn_unused_result))

1736

bool interface_is_up(const char *interface){

1737

struct ifreq ifr;

1738

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

1739

if(debug){

1740

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

1741

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

1742

}

1743

return false;

1744

}

1745

1746

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

1747

}

1748

1749

/*

1750

* This function determines if a network interface is running

1751

*/

1752

__attribute__((nonnull, warn_unused_result))

1753

bool interface_is_running(const char *interface){

1754

struct ifreq ifr;

1755

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

1756

if(debug){

1757

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

1758

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

1759

}

1760

return false;

1761

}

1762

1763

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

1764

}

1765

1766

__attribute__((nonnull, pure, warn_unused_result))

1164

fprintf_plus(stderr, "Failed to get flags for interface \"%s\"\n",

1165

if_entry->d_name);

1166

}

1167

return 0;

1168

}

1169

1170

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

1171

return 0;

1172

}

1173

return 1;

1174

}

1175

1176

/*

1177

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

1178

* corresponds to an acceptable network device which is up.

1179

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

1180

*/

1181

int up_interface(const struct dirent *if_entry){

1182

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

1183

return 0;

1184

}

1185

1186

struct ifreq ifr;

1187

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

1188

if(debug){

1189

fprintf_plus(stderr, "Failed to get flags for interface \"%s\"\n",

1190

if_entry->d_name);

1191

}

1192

return 0;

1193

}

1194

1195

/* Reject down interfaces */

1196

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

1197

if(debug){

1198

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

1199

if_entry->d_name);

1200

}

1201

return 0;

1202

}

1203

1204

/* Reject non-running interfaces */

1205

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

1206

if(debug){

1207

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

1208

if_entry->d_name);

1209

}

1210

return 0;

1211

}

1212

1213

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

1214

return 0;

1215

}

1216

return 1;

1217

}

1218

1767

1219

int notdotentries(const struct dirent *direntry){

1768

1220

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

1769

1221

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

1776

1228

}

1777

1229

1778

1230

/* Is this directory entry a runnable program? */

1779

__attribute__((nonnull, warn_unused_result))

1780

1231

int runnable_hook(const struct dirent *direntry){

1781

1232

int ret;

1782

1233

size_t sret;

1790

1241

sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

1791

1242

"abcdefghijklmnopqrstuvwxyz"

1792

1243

"0123456789"

1793

"_.-");

1244

"_-");

1794

1245

if((direntry->d_name)[sret] != '\0'){

1795

1246

/* Contains non-allowed characters */

1796

1247

if(debug){

1797

1248

fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",

1798

direntry->d_name);

1249

direntry->d_name);

1799

1250

}

1800

1251

return 0;

1801

1252

}

1802

1253

1803

ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);

1254

char *fullname = NULL;

1255

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

1256

if(ret < 0){

1257

perror_plus("asprintf");

1258

return 0;

1259

}

1260

1261

ret = stat(fullname, &st);

1804

1262

if(ret == -1){

1805

1263

if(debug){

1806

1264

perror_plus("Could not stat hook");

1811

1269

/* Not a regular file */

1812

1270

if(debug){

1813

1271

fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",

1814

direntry->d_name);

1272

direntry->d_name);

1815

1273

}

1816

1274

return 0;

1817

1275

}

1819

1277

/* Not executable */

1820

1278

if(debug){

1821

1279

fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",

1822

direntry->d_name);

1280

direntry->d_name);

1823

1281

}

1824

1282

return 0;

1825

1283

}

1826

if(debug){

1827

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

1828

direntry->d_name);

1829

}

1830

1284

return 1;

1831

1285

}

1832

1286

1833

__attribute__((nonnull, warn_unused_result))

1834

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1835

mandos_context *mc){

1287

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1836

1288

int ret;

1837

1289

struct timespec now;

1838

1290

struct timespec waited_time;

1839

1291

intmax_t block_time;

1840

1292

1841

1293

while(true){

1842

if(mc->current_server == NULL){

1843

if(debug){

1844

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

1845

" No timeout!\n");

1294

if(mc.current_server == NULL){

1295

if (debug){

1296

fprintf_plus(stderr, "Wait until first server is found. No timeout!\n");

1846

1297

}

1847

1298

ret = avahi_simple_poll_iterate(s, -1);

1848

1299

} else {

1849

if(debug){

1850

fprintf_plus(stderr, "Check current_server if we should run"

1851

" it, or wait\n");

1300

if (debug){

1301

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

1302

" or wait\n");

1852

1303

}

1853

1304

/* the current time */

1854

1305

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1859

1310

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

1860

1311

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

1861

1312

waited_time.tv_sec = (now.tv_sec

1862

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

1313

- mc.current_server->last_seen.tv_sec);

1863

1314

waited_time.tv_nsec = (now.tv_nsec

1864

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

1315

- mc.current_server->last_seen.tv_nsec);

1865

1316

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

1866

1317

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

1867

1318

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

1869

1320

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

1870

1321

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

1871

1322

1872

if(debug){

1873

fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",

1874

block_time);

1323

if (debug){

1324

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

1875

1325

}

1876

1326

1877

1327

if(block_time <= 0){

1878

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

1879

mc->current_server->port,

1880

mc->current_server->if_index,

1881

mc->current_server->af, mc);

1328

ret = start_mandos_communication(mc.current_server->ip,

1329

mc.current_server->port,

1330

mc.current_server->if_index,

1331

mc.current_server->af);

1882

1332

if(ret == 0){

1883

avahi_simple_poll_quit(s);

1333

avahi_simple_poll_quit(mc.simple_poll);

1884

1334

return 0;

1885

1335

}

1886

1336

ret = clock_gettime(CLOCK_MONOTONIC,

1887

&mc->current_server->last_seen);

1337

&mc.current_server->last_seen);

1888

1338

if(ret == -1){

1889

1339

perror_plus("clock_gettime");

1890

1340

return -1;

1891

1341

}

1892

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

1342

mc.current_server = mc.current_server->next;

1893

1343

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

1894

1344

servers, but don't block */

1895

1345

}

1897

1347

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

1898

1348

}

1899

1349

if(ret != 0){

1900

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

1350

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

1901

1351

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

1902

1352

}

1903

1353

}

1904

1354

}

1905

1355

}

1906

1356

1907

__attribute__((nonnull))

1908

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

1909

const float delay){

1910

struct dirent **direntries = NULL;

1911

if(hookdir_fd == -1){

1912

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1913

| O_CLOEXEC);

1914

if(hookdir_fd == -1){

1915

if(errno == ENOENT){

1916

if(debug){

1917

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

1918

" found\n", hookdir);

1919

}

1920

} else {

1921

perror_plus("open");

1922

}

1923

return;

1924

}

1925

}

1926

int numhooks = scandirat(hookdir_fd, ".", &direntries,

1927

runnable_hook, alphasort);

1928

if(numhooks == -1){

1929

perror_plus("scandir");

1930

return;

1931

}

1932

struct dirent *direntry;

1933

int ret;

1934

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

1935

if(devnull == -1){

1936

perror_plus("open(\"/dev/null\", O_RDONLY)");

1937

return;

1938

}

1939

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

1940

direntry = direntries[i];

1941

if(debug){

1942

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

1943

direntry->d_name);

1944

}

1945

pid_t hook_pid = fork();

1946

if(hook_pid == 0){

1947

/* Child */

1948

/* Raise privileges */

1949

errno = raise_privileges_permanently();

1950

if(errno != 0){

1951

perror_plus("Failed to raise privileges");

1952

_exit(EX_NOPERM);

1953

}

1954

/* Set group */

1955

errno = 0;

1956

ret = setgid(0);

1957

if(ret == -1){

1958

perror_plus("setgid");

1959

_exit(EX_NOPERM);

1960

}

1961

/* Reset supplementary groups */

1962

errno = 0;

1963

ret = setgroups(0, NULL);

1964

if(ret == -1){

1965

perror_plus("setgroups");

1966

_exit(EX_NOPERM);

1967

}

1968

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

1969

if(ret == -1){

1970

perror_plus("setenv");

1971

_exit(EX_OSERR);

1972

}

1973

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

1974

if(ret == -1){

1975

perror_plus("setenv");

1976

_exit(EX_OSERR);

1977

}

1978

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

1979

if(ret == -1){

1980

perror_plus("setenv");

1981

_exit(EX_OSERR);

1982

}

1983

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

1984

if(ret == -1){

1985

perror_plus("setenv");

1986

_exit(EX_OSERR);

1987

}

1988

char *delaystring;

1989

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

1990

if(ret == -1){

1991

perror_plus("asprintf");

1992

_exit(EX_OSERR);

1993

}

1994

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

1995

if(ret == -1){

1996

free(delaystring);

1997

perror_plus("setenv");

1998

_exit(EX_OSERR);

1999

}

2000

free(delaystring);

2001

if(connect_to != NULL){

2002

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

2003

if(ret == -1){

2004

perror_plus("setenv");

2005

_exit(EX_OSERR);

2006

}

2007

}

2008

int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,

2009

direntry->d_name,

2010

O_RDONLY));

2011

if(hook_fd == -1){

2012

perror_plus("openat");

2013

_exit(EXIT_FAILURE);

2014

}

2015

if(close(hookdir_fd) == -1){

2016

perror_plus("close");

2017

_exit(EXIT_FAILURE);

2018

}

2019

ret = dup2(devnull, STDIN_FILENO);

2020

if(ret == -1){

2021

perror_plus("dup2(devnull, STDIN_FILENO)");

2022

_exit(EX_OSERR);

2023

}

2024

ret = close(devnull);

2025

if(ret == -1){

2026

perror_plus("close");

2027

_exit(EX_OSERR);

2028

}

2029

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2030

if(ret == -1){

2031

perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");

2032

_exit(EX_OSERR);

2033

}

2034

if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },

2035

environ) == -1){

2036

perror_plus("fexecve");

2037

_exit(EXIT_FAILURE);

2038

}

2039

} else {

2040

if(hook_pid == -1){

2041

perror_plus("fork");

2042

free(direntry);

2043

continue;

2044

}

2045

int status;

2046

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

2047

perror_plus("waitpid");

2048

free(direntry);

2049

continue;

2050

}

2051

if(WIFEXITED(status)){

2052

if(WEXITSTATUS(status) != 0){

2053

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

2054

" with status %d\n", direntry->d_name,

2055

WEXITSTATUS(status));

2056

free(direntry);

2057

continue;

2058

}

2059

} else if(WIFSIGNALED(status)){

2060

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

2061

" signal %d\n", direntry->d_name,

2062

WTERMSIG(status));

2063

free(direntry);

2064

continue;

2065

} else {

2066

fprintf_plus(stderr, "Warning: network hook \"%s\""

2067

" crashed\n", direntry->d_name);

2068

free(direntry);

2069

continue;

2070

}

2071

}

2072

if(debug){

2073

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

2074

direntry->d_name);

2075

}

2076

free(direntry);

2077

}

2078

free(direntries);

2079

if(close(hookdir_fd) == -1){

2080

perror_plus("close");

2081

} else {

2082

hookdir_fd = -1;

2083

}

2084

close(devnull);

2085

}

2086

2087

__attribute__((nonnull, warn_unused_result))

2088

int bring_up_interface(const char *const interface,

2089

const float delay){

2090

int old_errno = errno;

2091

int ret;

2092

struct ifreq network;

2093

unsigned int if_index = if_nametoindex(interface);

2094

if(if_index == 0){

2095

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

2096

errno = old_errno;

2097

return ENXIO;

2098

}

2099

2100

if(quit_now){

2101

errno = old_errno;

2102

return EINTR;

2103

}

2104

2105

if(not interface_is_up(interface)){

2106

int ret_errno = 0;

2107

int ioctl_errno = 0;

2108

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

2109

ret_errno = errno;

2110

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

2111

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

2112

errno = old_errno;

2113

return ret_errno;

2114

}

2115

network.ifr_flags |= IFF_UP; /* set flag */

2116

2117

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

2118

if(sd == -1){

2119

ret_errno = errno;

2120

perror_plus("socket");

2121

errno = old_errno;

2122

return ret_errno;

2123

}

2124

2125

if(quit_now){

2126

ret = close(sd);

2127

if(ret == -1){

2128

perror_plus("close");

2129

}

2130

errno = old_errno;

2131

return EINTR;

2132

}

2133

2134

if(debug){

2135

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

2136

interface);

2137

}

2138

2139

/* Raise privileges */

2140

ret_errno = raise_privileges();

2141

if(ret_errno != 0){

2142

errno = ret_errno;

2143

perror_plus("Failed to raise privileges");

2144

}

2145

2146

#ifdef __linux__

2147

int ret_linux;

2148

bool restore_loglevel = false;

2149

if(ret_errno == 0){

2150

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2151

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

2152

ret_linux = klogctl(8, NULL, 5);

2153

if(ret_linux == -1){

2154

perror_plus("klogctl");

2155

} else {

2156

restore_loglevel = true;

2157

}

2158

}

2159

#endif /* __linux__ */

2160

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

2161

ioctl_errno = errno;

2162

#ifdef __linux__

2163

if(restore_loglevel){

2164

ret_linux = klogctl(7, NULL, 0);

2165

if(ret_linux == -1){

2166

perror_plus("klogctl");

2167

}

2168

}

2169

#endif /* __linux__ */

2170

2171

/* If raise_privileges() succeeded above */

2172

if(ret_errno == 0){

2173

/* Lower privileges */

2174

ret_errno = lower_privileges();

2175

if(ret_errno != 0){

2176

errno = ret_errno;

2177

perror_plus("Failed to lower privileges");

2178

}

2179

}

2180

2181

/* Close the socket */

2182

ret = close(sd);

2183

if(ret == -1){

2184

perror_plus("close");

2185

}

2186

2187

if(ret_setflags == -1){

2188

errno = ioctl_errno;

2189

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2190

errno = old_errno;

2191

return ioctl_errno;

2192

}

2193

} else if(debug){

2194

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

2195

interface);

2196

}

2197

2198

/* Sleep checking until interface is running.

2199

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

2200

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

2201

if(interface_is_running(interface)){

2202

break;

2203

}

2204

struct timespec sleeptime = { .tv_nsec = 250000000 };

2205

ret = nanosleep(&sleeptime, NULL);

2206

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

2207

perror_plus("nanosleep");

2208

}

2209

}

2210

2211

errno = old_errno;

2212

return 0;

2213

}

2214

2215

__attribute__((nonnull, warn_unused_result))

2216

int take_down_interface(const char *const interface){

2217

int old_errno = errno;

2218

struct ifreq network;

2219

unsigned int if_index = if_nametoindex(interface);

2220

if(if_index == 0){

2221

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

2222

errno = old_errno;

2223

return ENXIO;

2224

}

2225

if(interface_is_up(interface)){

2226

int ret_errno = 0;

2227

int ioctl_errno = 0;

2228

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

2229

ret_errno = errno;

2230

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

2231

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

2232

errno = old_errno;

2233

return ret_errno;

2234

}

2235

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

2236

2237

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

2238

if(sd == -1){

2239

ret_errno = errno;

2240

perror_plus("socket");

2241

errno = old_errno;

2242

return ret_errno;

2243

}

2244

2245

if(debug){

2246

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

2247

interface);

2248

}

2249

2250

/* Raise privileges */

2251

ret_errno = raise_privileges();

2252

if(ret_errno != 0){

2253

errno = ret_errno;

2254

perror_plus("Failed to raise privileges");

2255

}

2256

2257

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

2258

ioctl_errno = errno;

2259

2260

/* If raise_privileges() succeeded above */

2261

if(ret_errno == 0){

2262

/* Lower privileges */

2263

ret_errno = lower_privileges();

2264

if(ret_errno != 0){

2265

errno = ret_errno;

2266

perror_plus("Failed to lower privileges");

2267

}

2268

}

2269

2270

/* Close the socket */

2271

int ret = close(sd);

2272

if(ret == -1){

2273

perror_plus("close");

2274

}

2275

2276

if(ret_setflags == -1){

2277

errno = ioctl_errno;

2278

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2279

errno = old_errno;

2280

return ioctl_errno;

2281

}

2282

} else if(debug){

2283

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

2284

interface);

2285

}

2286

2287

errno = old_errno;

2288

return 0;

2289

}

2290

2291

1357

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

2292

mandos_context mc = { .server = NULL, .dh_bits = 0,

2293

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

2294

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2295

.current_server = NULL, .interfaces = NULL,

2296

.interfaces_size = 0 };

2297

1358

AvahiSServiceBrowser *sb = NULL;

2298

error_t ret_errno;

1359

int error;

2299

1360

int ret;

2300

1361

intmax_t tmpmax;

2301

1362

char *tmp;

2302

1363

int exitcode = EXIT_SUCCESS;

2303

char *interfaces_to_take_down = NULL;

2304

size_t interfaces_to_take_down_size = 0;

2305

char run_tempdir[] = "/run/tmp/mandosXXXXXX";

2306

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

2307

char *tempdir = NULL;

1364

const char *interface = "";

1365

struct ifreq network;

1366

int sd = -1;

1367

bool take_down_interface = false;

1368

uid_t uid;

1369

gid_t gid;

1370

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

1371

bool tempdir_created = false;

2308

1372

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2309

1373

const char *seckey = PATHDIR "/" SECKEY;

2310

1374

const char *pubkey = PATHDIR "/" PUBKEY;

2311

const char *dh_params_file = NULL;

2312

char *interfaces_hooks = NULL;

2313

1375

2314

1376

bool gnutls_initialized = false;

2315

1377

bool gpgme_initialized = false;

2367

1429

.doc = "Bit length of the prime number used in the"

2368

1430

" Diffie-Hellman key exchange",

2369

1431

.group = 2 },

2370

{ .name = "dh-params", .key = 134,

2371

.arg = "FILE",

2372

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2373

" for the Diffie-Hellman key exchange",

2374

.group = 2 },

2375

1432

{ .name = "priority", .key = 130,

2376

1433

.arg = "STRING",

2377

1434

.doc = "GnuTLS priority string for the TLS handshake",

2382

1439

.group = 2 },

2383

1440

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

2384

1441

.arg = "SECONDS",

2385

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

1442

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

2386

1443

.group = 2 },

2387

1444

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

2388

1445

.arg = "DIR",

2411

1468

connect_to = arg;

2412

1469

break;

2413

1470

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

2414

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

2415

arg, (int)',');

2416

if(ret_errno != 0){

2417

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

2418

}

1471

interface = arg;

2419

1472

break;

2420

1473

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

2421

1474

seckey = arg;

2432

1485

}

2433

1486

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

2434

1487

break;

2435

case 134: /* --dh-params */

2436

dh_params_file = arg;

2437

break;

2438

1488

case 130: /* --priority */

2439

1489

mc.priority = arg;

2440

1490

break;

2467

1517

argp_state_help(state, state->out_stream,

2468

1518

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2469

1519

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

1520

fprintf_plus(state->out_stream, "Mandos plugin mandos-client: ");

2470

1521

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

2471

1522

exit(argp_err_exit_status);

2472

1523

break;

2480

1531

.args_doc = "",

2481

1532

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

2482

1533

" passwords from a Mandos server" };

2483

ret_errno = argp_parse(&argp, argc, argv,

2484

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2485

switch(ret_errno){

1534

ret = argp_parse(&argp, argc, argv,

1535

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1536

switch(ret){

2486

1537

case 0:

2487

1538

break;

2488

1539

case ENOMEM:

2489

1540

default:

2490

errno = ret_errno;

1541

errno = ret;

2491

1542

perror_plus("argp_parse");

2492

1543

exitcode = EX_OSERR;

2493

1544

goto end;

2496

1547

goto end;

2497

1548

}

2498

1549

}

2499

1550

2500

1551

{

2501

1552

/* Work around Debian bug #633582:

2502

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

2503

2504

/* Re-raise privileges */

2505

ret = raise_privileges();

2506

if(ret != 0){

2507

errno = ret;

2508

perror_plus("Failed to raise privileges");

1553

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

1554

struct stat st;

1555

1556

/* Re-raise priviliges */

1557

errno = 0;

1558

ret = seteuid(0);

1559

if(ret == -1){

1560

perror_plus("seteuid");

1561

}

1562

1563

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

1564

int seckey_fd = open(seckey, O_RDONLY);

1565

if(seckey_fd == -1){

1566

perror_plus("open");

1567

} else {

1568

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

1569

if(ret == -1){

1570

perror_plus("fstat");

1571

} else {

1572

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

1573

ret = fchown(seckey_fd, uid, gid);

1574

if(ret == -1){

1575

perror_plus("fchown");

1576

}

1577

}

1578

}

1579

TEMP_FAILURE_RETRY(close(seckey_fd));

1580

}

1581

}

1582

1583

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

1584

int pubkey_fd = open(pubkey, O_RDONLY);

1585

if(pubkey_fd == -1){

1586

perror_plus("open");

1587

} else {

1588

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

1589

if(ret == -1){

1590

perror_plus("fstat");

1591

} else {

1592

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

1593

ret = fchown(pubkey_fd, uid, gid);

1594

if(ret == -1){

1595

perror_plus("fchown");

1596

}

1597

}

1598

}

1599

TEMP_FAILURE_RETRY(close(pubkey_fd));

1600

}

1601

}

1602

1603

/* Lower privileges */

1604

errno = 0;

1605

ret = seteuid(uid);

1606

if(ret == -1){

1607

perror_plus("seteuid");

1608

}

1609

}

1610

1611

/* Find network hooks and run them */

1612

{

1613

struct dirent **direntries;

1614

struct dirent *direntry;

1615

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

1616

alphasort);

1617

if(numhooks == -1){

1618

perror_plus("scandir");

2509

1619

} else {

2510

struct stat st;

2511

2512

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

2513

int seckey_fd = open(seckey, O_RDONLY);

2514

if(seckey_fd == -1){

2515

perror_plus("open");

2516

} else {

2517

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

2518

if(ret == -1){

2519

perror_plus("fstat");

2520

} else {

2521

if(S_ISREG(st.st_mode)

2522

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

2523

ret = fchown(seckey_fd, uid, gid);

2524

if(ret == -1){

2525

perror_plus("fchown");

2526

}

2527

}

2528

}

2529

close(seckey_fd);

2530

}

2531

}

2532

2533

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

2534

int pubkey_fd = open(pubkey, O_RDONLY);

2535

if(pubkey_fd == -1){

2536

perror_plus("open");

2537

} else {

2538

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

2539

if(ret == -1){

2540

perror_plus("fstat");

2541

} else {

2542

if(S_ISREG(st.st_mode)

2543

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

2544

ret = fchown(pubkey_fd, uid, gid);

2545

if(ret == -1){

2546

perror_plus("fchown");

2547

}

2548

}

2549

}

2550

close(pubkey_fd);

2551

}

2552

}

2553

2554

if(dh_params_file != NULL

2555

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2556

int dhparams_fd = open(dh_params_file, O_RDONLY);

2557

if(dhparams_fd == -1){

2558

perror_plus("open");

2559

} else {

2560

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

2561

if(ret == -1){

2562

perror_plus("fstat");

2563

} else {

2564

if(S_ISREG(st.st_mode)

2565

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

2566

ret = fchown(dhparams_fd, uid, gid);

2567

if(ret == -1){

2568

perror_plus("fchown");

2569

}

2570

}

2571

}

2572

close(dhparams_fd);

2573

}

2574

}

2575

2576

/* Lower privileges */

2577

ret = lower_privileges();

2578

if(ret != 0){

2579

errno = ret;

2580

perror_plus("Failed to lower privileges");

2581

}

2582

}

2583

}

2584

2585

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

2586

{

2587

char *interface = NULL;

2588

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

2589

interface))){

2590

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

2591

and if_nametoindex(interface) == 0){

2592

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

2593

fprintf_plus(stderr, "Not using nonexisting interface"

2594

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

2595

}

2596

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

2597

interface = NULL;

2598

}

2599

}

2600

}

2601

2602

/* Run network hooks */

2603

{

2604

if(mc.interfaces != NULL){

2605

interfaces_hooks = malloc(mc.interfaces_size);

2606

if(interfaces_hooks == NULL){

2607

perror_plus("malloc");

2608

goto end;

2609

}

2610

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

2611

argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');

2612

}

2613

run_network_hooks("start", interfaces_hooks != NULL ?

2614

interfaces_hooks : "", delay);

1620

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

1621

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

1622

direntry = direntries[0];

1623

char *fullname = NULL;

1624

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

1625

if(ret < 0){

1626

perror_plus("asprintf");

1627

continue;

1628

}

1629

pid_t hook_pid = fork();

1630

if(hook_pid == 0){

1631

/* Child */

1632

dup2(devnull, STDIN_FILENO);

1633

close(devnull);

1634

dup2(STDERR_FILENO, STDOUT_FILENO);

1635

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

1636

if(ret == -1){

1637

perror_plus("setenv");

1638

exit(1);

1639

}

1640

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

1641

if(ret == -1){

1642

perror_plus("setenv");

1643

exit(1);

1644

}

1645

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

1646

if(ret == -1){

1647

perror_plus("setenv");

1648

exit(1);

1649

}

1650

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

1651

if(ret == -1){

1652

perror_plus("setenv");

1653

exit(1);

1654

}

1655

char *delaystring;

1656

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

1657

if(ret == -1){

1658

perror_plus("asprintf");

1659

exit(1);

1660

}

1661

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

1662

if(ret == -1){

1663

free(delaystring);

1664

perror_plus("setenv");

1665

exit(1);

1666

}

1667

free(delaystring);

1668

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

1669

perror_plus("execl");

1670

} else {

1671

int status;

1672

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

1673

perror_plus("waitpid");

1674

free(fullname);

1675

continue;

1676

}

1677

if(WIFEXITED(status)){

1678

if(WEXITSTATUS(status) != 0){

1679

fprintf_plus(stderr, "Warning: network hook \"%s\" exited"

1680

" with status %d\n", direntry->d_name,

1681

WEXITSTATUS(status));

1682

free(fullname);

1683

continue;

1684

}

1685

} else if(WIFSIGNALED(status)){

1686

fprintf_plus(stderr, "Warning: network hook \"%s\" died by"

1687

" signal %d\n", direntry->d_name,

1688

WTERMSIG(status));

1689

free(fullname);

1690

continue;

1691

} else {

1692

fprintf_plus(stderr, "Warning: network hook \"%s\" crashed\n",

1693

direntry->d_name);

1694

free(fullname);

1695

continue;

1696

}

1697

}

1698

free(fullname);

1699

if(quit_now){

1700

goto end;

1701

}

1702

}

1703

close(devnull);

1704

}

2615

1705

}

2616

1706

2617

1707

if(not debug){

2618

1708

avahi_set_log_function(empty_log);

2619

1709

}

2620

1710

1711

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

1712

struct dirent **direntries;

1713

/* First look for interfaces that are up */

1714

ret = scandir(sys_class_net, &direntries, up_interface,

1715

alphasort);

1716

if(ret == 0){

1717

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

1718

free(direntries);

1719

ret = scandir(sys_class_net, &direntries, good_interface,

1720

alphasort);

1721

}

1722

if(ret >= 1){

1723

/* Pick the first interface returned */

1724

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

1725

if(debug){

1726

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

1727

}

1728

if(interface == NULL){

1729

perror_plus("malloc");

1730

free(direntries);

1731

exitcode = EXIT_FAILURE;

1732

goto end;

1733

}

1734

free(direntries);

1735

} else {

1736

free(direntries);

1737

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

1738

exitcode = EXIT_FAILURE;

1739

goto end;

1740

}

1741

}

1742

2621

1743

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

2622

1744

from the signal handler */

2623

1745

/* Initialize the pseudo-RNG for Avahi */

2624

1746

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

2625

simple_poll = avahi_simple_poll_new();

2626

if(simple_poll == NULL){

2627

fprintf_plus(stderr,

2628

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

1747

mc.simple_poll = avahi_simple_poll_new();

1748

if(mc.simple_poll == NULL){

1749

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

2629

1750

exitcode = EX_UNAVAILABLE;

2630

1751

goto end;

2631

1752

}

2693

1814

}

2694

1815

}

2695

1816

2696

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

2697

if(mc.interfaces == NULL){

2698

struct dirent **direntries = NULL;

2699

/* Look for any good interfaces */

2700

ret = scandir(sys_class_net, &direntries, good_interface,

2701

alphasort);

2702

if(ret >= 1){

2703

/* Add all found interfaces to interfaces list */

2704

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

2705

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

2706

direntries[i]->d_name);

2707

if(ret_errno != 0){

2708

errno = ret_errno;

2709

perror_plus("argz_add");

2710

free(direntries[i]);

2711

continue;

2712

}

2713

if(debug){

2714

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

2715

direntries[i]->d_name);

2716

}

2717

free(direntries[i]);

2718

}

2719

free(direntries);

1817

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

1818

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

1819

if_index = (AvahiIfIndex) if_nametoindex(interface);

1820

if(if_index == 0){

1821

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

1822

exitcode = EX_UNAVAILABLE;

1823

goto end;

1824

}

1825

1826

if(quit_now){

1827

goto end;

1828

}

1829

1830

/* Re-raise priviliges */

1831

errno = 0;

1832

ret = seteuid(0);

1833

if(ret == -1){

1834

perror_plus("seteuid");

1835

}

1836

1837

#ifdef __linux__

1838

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1839

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

1840

ret = klogctl(8, NULL, 5);

1841

bool restore_loglevel = true;

1842

if(ret == -1){

1843

restore_loglevel = false;

1844

perror_plus("klogctl");

1845

}

1846

#endif /* __linux__ */

1847

1848

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1849

if(sd < 0){

1850

perror_plus("socket");

1851

exitcode = EX_OSERR;

1852

#ifdef __linux__

1853

if(restore_loglevel){

1854

ret = klogctl(7, NULL, 0);

1855

if(ret == -1){

1856

perror_plus("klogctl");

1857

}

1858

}

1859

#endif /* __linux__ */

1860

/* Lower privileges */

1861

errno = 0;

1862

ret = seteuid(uid);

1863

if(ret == -1){

1864

perror_plus("seteuid");

1865

}

1866

goto end;

1867

}

1868

strcpy(network.ifr_name, interface);

1869

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

1870

if(ret == -1){

1871

perror_plus("ioctl SIOCGIFFLAGS");

1872

#ifdef __linux__

1873

if(restore_loglevel){

1874

ret = klogctl(7, NULL, 0);

1875

if(ret == -1){

1876

perror_plus("klogctl");

1877

}

1878

}

1879

#endif /* __linux__ */

1880

exitcode = EX_OSERR;

1881

/* Lower privileges */

1882

errno = 0;

1883

ret = seteuid(uid);

1884

if(ret == -1){

1885

perror_plus("seteuid");

1886

}

1887

goto end;

1888

}

1889

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

1890

network.ifr_flags |= IFF_UP;

1891

take_down_interface = true;

1892

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

1893

if(ret == -1){

1894

take_down_interface = false;

1895

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1896

exitcode = EX_OSERR;

1897

#ifdef __linux__

1898

if(restore_loglevel){

1899

ret = klogctl(7, NULL, 0);

1900

if(ret == -1){

1901

perror_plus("klogctl");

1902

}

1903

}

1904

#endif /* __linux__ */

1905

/* Lower privileges */

1906

errno = 0;

1907

ret = seteuid(uid);

1908

if(ret == -1){

1909

perror_plus("seteuid");

1910

}

1911

goto end;

1912

}

1913

}

1914

/* Sleep checking until interface is running.

1915

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

1916

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

1917

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

1918

if(ret == -1){

1919

perror_plus("ioctl SIOCGIFFLAGS");

1920

} else if(network.ifr_flags & IFF_RUNNING){

1921

break;

1922

}

1923

struct timespec sleeptime = { .tv_nsec = 250000000 };

1924

ret = nanosleep(&sleeptime, NULL);

1925

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

1926

perror_plus("nanosleep");

1927

}

1928

}

1929

if(not take_down_interface){

1930

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

1931

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

1932

if(ret == -1){

1933

perror_plus("close");

1934

}

1935

}

1936

#ifdef __linux__

1937

if(restore_loglevel){

1938

/* Restores kernel loglevel to default */

1939

ret = klogctl(7, NULL, 0);

1940

if(ret == -1){

1941

perror_plus("klogctl");

1942

}

1943

}

1944

#endif /* __linux__ */

1945

/* Lower privileges */

1946

errno = 0;

1947

if(take_down_interface){

1948

/* Lower privileges */

1949

ret = seteuid(uid);

1950

if(ret == -1){

1951

perror_plus("seteuid");

1952

}

2720

1953

} else {

2721

if(ret == 0){

2722

free(direntries);

2723

}

2724

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

2725

exitcode = EXIT_FAILURE;

2726

goto end;

2727

}

2728

}

2729

2730

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

2731

{

2732

char *interface = NULL;

2733

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

2734

interface))){

2735

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

2736

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

2737

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

2738

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

2739

interface);

2740

interface = NULL;

2741

while((interface = argz_next(mc.interfaces,

2742

mc.interfaces_size, interface))){

2743

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

2744

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

2745

interface);

2746

interface = NULL;

2747

}

2748

}

2749

break;

2750

}

2751

bool interface_was_up = interface_is_up(interface);

2752

errno = bring_up_interface(interface, delay);

2753

if(not interface_was_up){

2754

if(errno != 0){

2755

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2756

" %s\n", interface, strerror(errno));

2757

} else {

2758

errno = argz_add(&interfaces_to_take_down,

2759

&interfaces_to_take_down_size,

2760

interface);

2761

if(errno != 0){

2762

perror_plus("argz_add");

2763

}

2764

}

2765

}

2766

}

2767

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

2768

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

2769

}

2770

}

2771

2772

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

2773

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

2774

if(debug){

2775

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

2776

mc.interfaces);

2777

}

2778

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

1954

/* Lower privileges permanently */

1955

ret = setuid(uid);

1956

if(ret == -1){

1957

perror_plus("setuid");

1958

}

1959

}

2779

1960

}

2780

1961

2781

1962

if(quit_now){

2782

1963

goto end;

2783

1964

}

2784

1965

2785

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

1966

ret = init_gnutls_global(pubkey, seckey);

2786

1967

if(ret == -1){

2787

1968

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

2788

1969

exitcode = EX_UNAVAILABLE;

2795

1976

goto end;

2796

1977

}

2797

1978

2798

/* Try /run/tmp before /tmp */

2799

tempdir = mkdtemp(run_tempdir);

2800

if(tempdir == NULL and errno == ENOENT){

2801

if(debug){

2802

fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",

2803

run_tempdir, old_tempdir);

2804

}

2805

tempdir = mkdtemp(old_tempdir);

2806

}

2807

if(tempdir == NULL){

1979

if(mkdtemp(tempdir) == NULL){

2808

1980

perror_plus("mkdtemp");

2809

1981

goto end;

2810

1982

}

1983

tempdir_created = true;

2811

1984

2812

1985

if(quit_now){

2813

1986

goto end;

2814

1987

}

2815

1988

2816

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

1989

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

2817

1990

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

2818

1991

exitcode = EX_UNAVAILABLE;

2819

1992

goto end;

2829

2002

/* Connect directly, do not use Zeroconf */

2830

2003

/* (Mainly meant for debugging) */

2831

2004

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

2832

2833

2005

if(address == NULL){

2834

2006

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

2835

2007

exitcode = EX_USAGE;

2840

2012

goto end;

2841

2013

}

2842

2014

2843

in_port_t port;

2015

uint16_t port;

2844

2016

errno = 0;

2845

2017

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

2846

2018

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

2847

or tmpmax != (in_port_t)tmpmax){

2019

or tmpmax != (uint16_t)tmpmax){

2848

2020

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

2849

2021

exitcode = EX_USAGE;

2850

2022

goto end;

2851

2023

}

2852

2024

2853

2025

if(quit_now){

2854

2026

goto end;

2855

2027

}

2856

2028

2857

port = (in_port_t)tmpmax;

2029

port = (uint16_t)tmpmax;

2858

2030

*address = '\0';

2859

2031

/* Colon in address indicates IPv6 */

2860

2032

int af;

2876

2048

}

2877

2049

2878

2050

while(not quit_now){

2879

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

2880

&mc);

2051

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

2881

2052

if(quit_now or ret == 0){

2882

2053

break;

2883

2054

}

2884

2055

if(debug){

2885

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

2886

(int)retry_interval);

2056

fprintf_plus(stderr, "Retrying in %d seconds\n", (int)retry_interval);

2887

2057

}

2888

sleep((unsigned int)retry_interval);

2058

sleep((int)retry_interval);

2889

2059

}

2890

2060

2891

if(not quit_now){

2061

if (not quit_now){

2892

2062

exitcode = EXIT_SUCCESS;

2893

2063

}

2894

2064

2909

2079

config.publish_domain = 0;

2910

2080

2911

2081

/* Allocate a new server */

2912

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2913

&config, NULL, NULL, &ret);

2082

mc.server = avahi_server_new(avahi_simple_poll_get

2083

(mc.simple_poll), &config, NULL,

2084

NULL, &error);

2914

2085

2915

2086

/* Free the Avahi configuration data */

2916

2087

avahi_server_config_free(&config);

2919

2090

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

2920

2091

if(mc.server == NULL){

2921

2092

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

2922

avahi_strerror(ret));

2093

avahi_strerror(error));

2923

2094

exitcode = EX_UNAVAILABLE;

2924

2095

goto end;

2925

2096

}

2931

2102

/* Create the Avahi service browser */

2932

2103

sb = avahi_s_service_browser_new(mc.server, if_index,

2933

2104

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2934

NULL, 0, browse_callback,

2935

(void *)&mc);

2105

NULL, 0, browse_callback, NULL);

2936

2106

if(sb == NULL){

2937

2107

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

2938

avahi_strerror(avahi_server_errno(mc.server)));

2108

avahi_strerror(avahi_server_errno(mc.server)));

2939

2109

exitcode = EX_UNAVAILABLE;

2940

2110

goto end;

2941

2111

}

2949

2119

if(debug){

2950

2120

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

2951

2121

}

2952

2953

ret = avahi_loop_with_timeout(simple_poll,

2954

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

2122

2123

ret = avahi_loop_with_timeout(mc.simple_poll,

2124

(int)(retry_interval * 1000));

2955

2125

if(debug){

2956

2126

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

2957

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

2127

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

2958

2128

}

2959

2129

2960

2130

end:

2961

2131

2962

2132

if(debug){

2963

if(signal_received){

2964

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

2965

argv[0], signal_received,

2966

strsignal(signal_received));

2967

} else {

2968

fprintf_plus(stderr, "%s exiting\n", argv[0]);

2969

}

2133

fprintf_plus(stderr, "%s exiting\n", argv[0]);

2970

2134

}

2971

2135

2972

2136

/* Cleanup things */

2973

free(mc.interfaces);

2974

2975

2137

if(sb != NULL)

2976

2138

avahi_s_service_browser_free(sb);

2977

2139

2978

2140

if(mc.server != NULL)

2979

2141

avahi_server_free(mc.server);

2980

2142

2981

if(simple_poll != NULL)

2982

avahi_simple_poll_free(simple_poll);

2143

if(mc.simple_poll != NULL)

2144

avahi_simple_poll_free(mc.simple_poll);

2983

2145

2984

2146

if(gnutls_initialized){

2985

2147

gnutls_certificate_free_credentials(mc.cred);

2148

gnutls_global_deinit();

2986

2149

gnutls_dh_params_deinit(mc.dh_params);

2987

2150

}

2988

2151

2989

2152

if(gpgme_initialized){

2990

2153

gpgme_release(mc.ctx);

2991

2154

}

2992

2155

2993

2156

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

2994

2157

has seen */

2995

2158

if(mc.current_server != NULL){

2996

2159

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

2997

2160

while(mc.current_server != NULL){

2998

2161

server *next = mc.current_server->next;

2999

#ifdef __GNUC__

3000

#pragma GCC diagnostic push

3001

#pragma GCC diagnostic ignored "-Wcast-qual"

3002

#endif

3003

free((char *)(mc.current_server->ip));

3004

#ifdef __GNUC__

3005

#pragma GCC diagnostic pop

3006

#endif

3007

2162

free(mc.current_server);

3008

2163

mc.current_server = next;

3009

2164

}

3010

2165

}

3011

2166

3012

/* Re-raise privileges */

3013

{

3014

ret = raise_privileges();

3015

if(ret != 0){

3016

errno = ret;

3017

perror_plus("Failed to raise privileges");

3018

} else {

3019

3020

/* Run network hooks */

3021

run_network_hooks("stop", interfaces_hooks != NULL ?

3022

interfaces_hooks : "", delay);

3023

3024

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

3025

{

3026

char *interface = NULL;

3027

while((interface = argz_next(interfaces_to_take_down,

3028

interfaces_to_take_down_size,

3029

interface))){

3030

ret = take_down_interface(interface);

3031

if(ret != 0){

3032

errno = ret;

3033

perror_plus("Failed to take down interface");

3034

}

3035

}

3036

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

3037

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

3038

" down\n");

3039

}

3040

}

2167

/* XXX run network hooks "stop" here */

2168

2169

/* Take down the network interface */

2170

if(take_down_interface){

2171

/* Re-raise priviliges */

2172

errno = 0;

2173

ret = seteuid(0);

2174

if(ret == -1){

2175

perror_plus("seteuid");

3041

2176

}

3042

3043

ret = lower_privileges_permanently();

3044

if(ret != 0){

3045

errno = ret;

3046

perror_plus("Failed to lower privileges permanently");

2177

if(geteuid() == 0){

2178

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

2179

if(ret == -1){

2180

perror_plus("ioctl SIOCGIFFLAGS");

2181

} else if(network.ifr_flags & IFF_UP){

2182

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

2183

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

2184

if(ret == -1){

2185

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2186

}

2187

}

2188

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

2189

if(ret == -1){

2190

perror_plus("close");

2191

}

2192

/* Lower privileges permanently */

2193

errno = 0;

2194

ret = setuid(uid);

2195

if(ret == -1){

2196

perror_plus("setuid");

2197

}

3047

2198

}

3048

2199

}

3049

2200

3050

free(interfaces_to_take_down);

3051

free(interfaces_hooks);

3052

3053

void clean_dir_at(int base, const char * const dirname,

3054

uintmax_t level){

2201

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

2202

if(tempdir_created){

3055

2203

struct dirent **direntries = NULL;

3056

int dret;

3057

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3058

O_RDONLY

3059

| O_NOFOLLOW

3060

| O_DIRECTORY

3061

| O_PATH));

3062

if(dir_fd == -1){

3063

perror_plus("open");

3064

}

3065

int numentries = scandirat(dir_fd, ".", &direntries,

3066

notdotentries, alphasort);

3067

if(numentries >= 0){

2204

struct dirent *direntry = NULL;

2205

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

2206

alphasort);

2207

if (numentries > 0){

3068

2208

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

3069

if(debug){

3070

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3071

dirname, direntries[i]->d_name);

3072

}

3073

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3074

if(dret == -1){

3075

if(errno == EISDIR){

3076

dret = unlinkat(dir_fd, direntries[i]->d_name,

3077

AT_REMOVEDIR);

3078

}

3079

if((dret == -1) and (errno == ENOTEMPTY)

3080

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3081

== 0) and (level == 0)){

3082

/* Recurse only in this special case */

3083

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3084

dret = 0;

3085

}

3086

if(dret == -1){

3087

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3088

direntries[i]->d_name, strerror(errno));

3089

}

3090

}

3091

free(direntries[i]);

3092

}

3093

3094

/* need to clean even if 0 because man page doesn't specify */

3095

free(direntries);

3096

if(numentries == -1){

3097

perror_plus("scandirat");

3098

}

3099

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3100

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

3101

perror_plus("rmdir");

3102

}

3103

} else {

3104

perror_plus("scandirat");

3105

}

3106

close(dir_fd);

3107

}

3108

3109

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

3110

if(tempdir != NULL){

3111

clean_dir_at(-1, tempdir, 0);

2209

direntry = direntries[i];

2210

char *fullname = NULL;

2211

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

2212

direntry->d_name);

2213

if(ret < 0){

2214

perror_plus("asprintf");

2215

continue;

2216

}

2217

ret = remove(fullname);

2218

if(ret == -1){

2219

fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname, strerror(errno));

2220

}

2221

free(fullname);

2222

}

2223

}

2224

2225

/* need to clean even if 0 because man page doesn't specify */

2226

free(direntries);

2227

if (numentries == -1){

2228

perror_plus("scandir");

2229

}

2230

ret = rmdir(tempdir);

2231

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

2232

perror_plus("rmdir");

2233

}

3112

2234

}

3113

2235

3114

2236

if(quit_now){