/mandos/trunk : revision 594.1.3

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

16

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

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

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stdout, ferror(), remove() */

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

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#include <stdint.h> /* uint16_t, uint32_t, intptr_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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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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*/

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

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

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setgid(), pause() */

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

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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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raise() */

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

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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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#ifdef __linux__

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

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111

init_gnutls_session(),

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112

GNUTLS_* */

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113

#include <gnutls/openpgp.h>

111

/* gnutls_certificate_set_openpgp_key_file(),

112

GNUTLS_OPENPGP_FMT_BASE64 */

114

/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

113

116

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/* GPGME */

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#include <gpgme.h> /* All GPGME types, constants and

123

126

#define PATHDIR "/conf/conf.d/mandos"

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127

#define SECKEY "seckey.txt"

125

128

#define PUBKEY "pubkey.txt"

129

#define HOOKDIR "/lib/mandos/network-hooks.d"

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130

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bool debug = false;

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132

static const char mandos_protocol_version[] = "1";

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

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135

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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uid_t uid = 65534;

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gid_t gid = 65534;

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140

134

141

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

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142

typedef struct server{

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172

166

173

/* Function to use when printing errors */

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174

void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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181

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

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

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va_list ap;

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va_start (ap, format);

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187

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

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program_invocation_short_name));

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

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}

191

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/*

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193

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

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

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* "buffer_length" is how much is already used.

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*/

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

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199

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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201

if(buffer == NULL){

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207

}

189

208

190

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

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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

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int af){

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int ret;

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

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if(new_server == NULL){

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perror_plus("malloc");

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return -1;

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return false;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

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223

perror_plus("strdup");

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return -1;

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return false;

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225

}

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/* Special case of first server */

209

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if (mc.current_server == NULL){

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238

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

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239

if(ret == -1){

222

240

perror_plus("clock_gettime");

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return -1;

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return false;

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242

}

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return 0;

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return true;

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}

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/*

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* Initialize GPGME.

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*/

231

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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

250

const char *tempdir){

233

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gpgme_error_t rc;

234

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gpgme_engine_info_t engine_info;

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253

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251

269

rc = gpgme_data_new_from_fd(&pgp_data, fd);

252

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if(rc != GPG_ERR_NO_ERROR){

253

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

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gpgme_strsource(rc), gpgme_strerror(rc));

271

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

272

gpgme_strsource(rc), gpgme_strerror(rc));

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273

return false;

256

274

}

257

275

258

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rc = gpgme_op_import(mc.ctx, pgp_data);

259

277

if(rc != GPG_ERR_NO_ERROR){

260

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

261

gpgme_strsource(rc), gpgme_strerror(rc));

278

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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280

return false;

263

281

}

264

282

271

289

}

272

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291

if(debug){

274

fprintf(stderr, "Initializing GPGME\n");

292

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

275

293

}

276

294

277

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/* Init GPGME */

278

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gpgme_check_version(NULL);

279

297

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

280

298

if(rc != GPG_ERR_NO_ERROR){

281

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

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gpgme_strsource(rc), gpgme_strerror(rc));

299

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

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gpgme_strsource(rc), gpgme_strerror(rc));

283

301

return false;

284

302

}

285

303

286

304

/* Set GPGME home directory for the OpenPGP engine only */

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305

rc = gpgme_get_engine_info(&engine_info);

288

306

if(rc != GPG_ERR_NO_ERROR){

289

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

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gpgme_strsource(rc), gpgme_strerror(rc));

307

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

308

gpgme_strsource(rc), gpgme_strerror(rc));

291

309

return false;

292

310

}

293

311

while(engine_info != NULL){

299

317

engine_info = engine_info->next;

300

318

}

301

319

if(engine_info == NULL){

302

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

320

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

321

tempdir);

303

322

return false;

304

323

}

305

324

306

325

/* Create new GPGME "context" */

307

326

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

308

327

if(rc != GPG_ERR_NO_ERROR){

309

fprintf(stderr, "bad gpgme_new: %s: %s\n",

310

gpgme_strsource(rc), gpgme_strerror(rc));

328

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

329

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

330

gpgme_strerror(rc));

311

331

return false;

312

332

}

313

333

332

352

ssize_t plaintext_length = 0;

333

353

334

354

if(debug){

335

fprintf(stderr, "Trying to decrypt OpenPGP data\n");

355

fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");

336

356

}

337

357

338

358

/* Create new GPGME data buffer from memory cryptotext */

339

359

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

340

360

0);

341

361

if(rc != GPG_ERR_NO_ERROR){

342

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

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gpgme_strsource(rc), gpgme_strerror(rc));

362

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return -1;

345

365

}

346

366

347

367

/* Create new empty GPGME data buffer for the plaintext */

348

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rc = gpgme_data_new(&dh_plain);

349

369

if(rc != GPG_ERR_NO_ERROR){

350

fprintf(stderr, "bad gpgme_data_new: %s: %s\n",

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gpgme_strsource(rc), gpgme_strerror(rc));

370

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

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

372

gpgme_strsource(rc), gpgme_strerror(rc));

352

373

gpgme_data_release(dh_crypto);

353

374

return -1;

354

375

}

357

378

data buffer */

358

379

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

359

380

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

381

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

382

gpgme_strsource(rc), gpgme_strerror(rc));

362

383

plaintext_length = -1;

363

384

if(debug){

364

385

gpgme_decrypt_result_t result;

365

386

result = gpgme_op_decrypt_result(mc.ctx);

366

387

if(result == NULL){

367

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

388

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

368

389

} else {

369

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

370

result->unsupported_algorithm);

371

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

372

result->wrong_key_usage);

390

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

391

result->unsupported_algorithm);

392

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

393

result->wrong_key_usage);

373

394

if(result->file_name != NULL){

374

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

395

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

375

396

}

376

397

gpgme_recipient_t recipient;

377

398

recipient = result->recipients;

378

399

while(recipient != NULL){

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

400

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

401

gpgme_pubkey_algo_name

402

(recipient->pubkey_algo));

403

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

404

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

405

recipient->status == GPG_ERR_NO_SECKEY

406

? "No" : "Yes");

385

407

recipient = recipient->next;

386

408

}

387

409

}

390

412

}

391

413

392

414

if(debug){

393

fprintf(stderr, "Decryption of OpenPGP data succeeded\n");

415

fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");

394

416

}

395

417

396

418

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

403

425

*plaintext = NULL;

404

426

while(true){

405

427

plaintext_capacity = incbuffer(plaintext,

406

(size_t)plaintext_length,

407

plaintext_capacity);

428

(size_t)plaintext_length,

429

plaintext_capacity);

408

430

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

431

perror_plus("incbuffer");

432

plaintext_length = -1;

433

goto decrypt_end;

412

434

}

413

435

414

436

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

427

449

}

428

450

429

451

if(debug){

430

fprintf(stderr, "Decrypted password is: ");

452

fprintf_plus(stderr, "Decrypted password is: ");

431

453

for(ssize_t i = 0; i < plaintext_length; i++){

432

454

fprintf(stderr, "%02hhX ", (*plaintext)[i]);

433

455

}

455

477

/* GnuTLS log function callback */

456

478

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

457

479

const char* string){

458

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

480

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

459

481

}

460

482

461

483

static int init_gnutls_global(const char *pubkeyfilename,

463

485

int ret;

464

486

465

487

if(debug){

466

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

488

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

467

489

}

468

490

469

491

ret = gnutls_global_init();

470

492

if(ret != GNUTLS_E_SUCCESS){

471

fprintf(stderr, "GnuTLS global_init: %s\n",

472

safer_gnutls_strerror(ret));

493

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

494

safer_gnutls_strerror(ret));

473

495

return -1;

474

496

}

475

497

484

506

/* OpenPGP credentials */

485

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

486

508

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

509

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

510

safer_gnutls_strerror(ret));

489

511

gnutls_global_deinit();

490

512

return -1;

491

513

}

492

514

493

515

if(debug){

494

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

495

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

496

seckeyfilename);

516

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

517

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

518

pubkeyfilename,

519

seckeyfilename);

497

520

}

498

521

499

522

ret = gnutls_certificate_set_openpgp_key_file

500

523

(mc.cred, pubkeyfilename, seckeyfilename,

501

524

GNUTLS_OPENPGP_FMT_BASE64);

502

525

if(ret != GNUTLS_E_SUCCESS){

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

526

fprintf_plus(stderr,

527

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

528

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

529

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

530

safer_gnutls_strerror(ret));

508

531

goto globalfail;

509

532

}

510

533

511

534

/* GnuTLS server initialization */

512

535

ret = gnutls_dh_params_init(&mc.dh_params);

513

536

if(ret != GNUTLS_E_SUCCESS){

514

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

515

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

537

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

538

" initialization: %s\n",

539

safer_gnutls_strerror(ret));

516

540

goto globalfail;

517

541

}

518

542

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

519

543

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

544

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

545

safer_gnutls_strerror(ret));

522

546

goto globalfail;

523

547

}

524

548

544

568

}

545

569

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

546

570

if(ret != GNUTLS_E_SUCCESS){

547

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

548

safer_gnutls_strerror(ret));

571

fprintf_plus(stderr,

572

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

573

safer_gnutls_strerror(ret));

549

574

}

550

575

551

576

{

558

583

}

559

584

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

560

585

if(ret != GNUTLS_E_SUCCESS){

561

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

562

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

563

safer_gnutls_strerror(ret));

586

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

587

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

588

safer_gnutls_strerror(ret));

564

589

gnutls_deinit(*session);

565

590

return -1;

566

591

}

575

600

}

576

601

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

577

602

if(ret != GNUTLS_E_SUCCESS){

578

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

579

safer_gnutls_strerror(ret));

603

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

604

safer_gnutls_strerror(ret));

580

605

gnutls_deinit(*session);

581

606

return -1;

582

607

}

627

652

pf = PF_INET;

628

653

break;

629

654

default:

630

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

655

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

631

656

errno = EINVAL;

632

657

return -1;

633

658

}

638

663

}

639

664

640

665

if(debug){

641

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

642

"\n", ip, port);

666

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

667

PRIu16 "\n", ip, port);

643

668

}

644

669

645

670

tcp_sd = socket(pf, SOCK_STREAM, 0);

671

696

}

672

697

if(ret == 0){

673

698

int e = errno;

674

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

699

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

675

700

errno = e;

676

701

goto mandos_end;

677

702

}

682

707

683

708

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

709

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

685

-Wunreachable-code*/

710

-Wunreachable-code*/

686

711

if(if_index == AVAHI_IF_UNSPEC){

687

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

688

" without a network interface\n");

712

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

713

" incomplete without a network interface\n");

689

714

errno = EINVAL;

690

715

goto mandos_end;

691

716

}

709

734

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

710

735

perror_plus("if_indextoname");

711

736

} else {

712

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

713

ip, interface, port);

737

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

738

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

714

739

}

715

740

} else {

716

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

717

port);

741

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

742

ip, port);

718

743

}

719

744

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

720

745

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

730

755

perror_plus("inet_ntop");

731

756

} else {

732

757

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

733

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

758

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

734

759

}

735

760

}

736

761

}

764

789

while(true){

765

790

size_t out_size = strlen(out);

766

791

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

767

out_size - written));

792

out_size - written));

768

793

if(ret == -1){

769

794

int e = errno;

770

795

perror_plus("write");

790

815

}

791

816

792

817

if(debug){

793

fprintf(stderr, "Establishing TLS session with %s\n", ip);

818

fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);

794

819

}

795

820

796

821

if(quit_now){

798

823

goto mandos_end;

799

824

}

800

825

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

826

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

827

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

828

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

829

gnutls_transport_set_ptr(session,

830

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

803

831

804

832

if(quit_now){

805

833

errno = EINTR;

816

844

817

845

if(ret != GNUTLS_E_SUCCESS){

818

846

if(debug){

819

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

847

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

820

848

gnutls_perror(ret);

821

849

}

822

850

errno = EPROTO;

826

854

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

827

855

828

856

if(debug){

829

fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",

830

ip);

857

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

858

" %s\n", ip);

831

859

}

832

860

833

861

while(true){

838

866

}

839

867

840

868

buffer_capacity = incbuffer(&buffer, buffer_length,

841

buffer_capacity);

869

buffer_capacity);

842

870

if(buffer_capacity == 0){

843

871

int e = errno;

844

872

perror_plus("incbuffer");

871

899

}

872

900

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

873

901

if(ret < 0){

874

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

902

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

903

"***\n");

875

904

gnutls_perror(ret);

876

905

errno = EPROTO;

877

906

goto mandos_end;

878

907

}

879

908

break;

880

909

default:

881

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

882

" encrypted session with Mandos server\n");

910

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

911

" encrypted session with Mandos server\n");

883

912

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

913

errno = EIO;

885

914

goto mandos_end;

890

919

}

891

920

892

921

if(debug){

893

fprintf(stderr, "Closing TLS session\n");

922

fprintf_plus(stderr, "Closing TLS session\n");

894

923

}

895

924

896

925

if(quit_now){

908

937

909

938

if(buffer_length > 0){

910

939

ssize_t decrypted_buffer_size;

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

940

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

913

941

&decrypted_buffer);

914

942

if(decrypted_buffer_size >= 0){

915

943

926

954

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

927

955

int e = errno;

928

956

if(debug){

929

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

930

strerror(errno));

957

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

958

strerror(errno));

931

959

}

932

960

errno = e;

933

961

goto mandos_end;

990

1018

switch(event){

991

1019

default:

992

1020

case AVAHI_RESOLVER_FAILURE:

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1021

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

1022

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

1023

domain,

1024

avahi_strerror(avahi_server_errno(mc.server)));

996

1025

break;

997

1026

998

1027

case AVAHI_RESOLVER_FOUND:

1000

1029

char ip[AVAHI_ADDRESS_STR_MAX];

1001

1030

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

1002

1031

if(debug){

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1032

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

1033

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

1034

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

1006

1035

}

1007

1036

int ret = start_mandos_communication(ip, port, interface,

1008

1037

avahi_proto_to_af(proto));

1009

1038

if(ret == 0){

1010

1039

avahi_simple_poll_quit(mc.simple_poll);

1011

1040

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1041

if(not add_server(ip, port, interface,

1042

avahi_proto_to_af(proto))){

1043

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

1044

" list\n", name);

1045

}

1014

1046

}

1015

1047

}

1016

1048

}

1040

1072

default:

1041

1073

case AVAHI_BROWSER_FAILURE:

1042

1074

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1075

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

1076

avahi_strerror(avahi_server_errno(mc.server)));

1045

1077

avahi_simple_poll_quit(mc.simple_poll);

1046

1078

return;

1047

1079

1054

1086

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

1055

1087

name, type, domain, protocol, 0,

1056

1088

resolve_callback, NULL) == NULL)

1057

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

1058

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

1089

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

1090

" %s\n", name,

1091

avahi_strerror(avahi_server_errno(mc.server)));

1059

1092

break;

1060

1093

1061

1094

case AVAHI_BROWSER_REMOVE:

1064

1097

case AVAHI_BROWSER_ALL_FOR_NOW:

1065

1098

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1066

1099

if(debug){

1067

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

1100

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

1101

" searching...\n");

1068

1102

}

1069

1103

break;

1070

1104

}

1085

1119

errno = old_errno;

1086

1120

}

1087

1121

1088

/*

1089

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

1090

* corresponds to an acceptable network device.

1091

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

1092

*/

1093

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

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

1097

return 0;

1098

}

1099

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

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

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

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

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

1113

/* read line from flags_fd */

1114

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

1115

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

1116

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

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

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

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

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

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1122

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

1123

int ret;

1124

1125

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

1126

if(s < 0){

1127

perror_plus("socket");

1128

return false;

1129

}

1130

strcpy(ifr->ifr_name, ifname);

1131

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1132

if(ret == -1){

1144

1133

if(debug){

1145

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

1146

flagstring, if_entry->d_name);

1134

perror_plus("ioctl SIOCGIFFLAGS");

1147

1135

}

1148

free(flagstring);

1149

return 0;

1136

return false;

1150

1137

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1138

return true;

1139

}

1140

1141

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

1142

1153

1143

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1144

if(ifr->ifr_flags & IFF_LOOPBACK){

1155

1145

if(debug){

1156

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

1157

if_entry->d_name);

1146

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

1147

ifname);

1158

1148

}

1159

return 0;

1149

return false;

1160

1150

}

1161

1151

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

1162

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

1152

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

1163

1153

if(debug){

1164

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

1165

if_entry->d_name);

1154

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

1155

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

1166

1156

}

1167

return 1;

1157

return true;

1168

1158

}

1169

1159

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

1170

if(not (flags & IFF_BROADCAST)){

1160

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

1171

1161

if(debug){

1172

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

1173

if_entry->d_name);

1162

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1163

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

1174

1164

}

1175

return 0;

1165

return false;

1176

1166

}

1177

1167

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

1178

if(flags & IFF_NOARP){

1168

if(ifr->ifr_flags & IFF_NOARP){

1179

1169

if(debug){

1180

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

1181

if_entry->d_name);

1170

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

1171

ifname);

1182

1172

}

1183

return 0;

1173

return false;

1184

1174

}

1175

1185

1176

/* Accept this device */

1186

1177

if(debug){

1187

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

1188

if_entry->d_name);

1178

fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);

1179

}

1180

return true;

1181

}

1182

1183

/*

1184

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

1185

* corresponds to an acceptable network device.

1186

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

1187

*/

1188

int good_interface(const struct dirent *if_entry){

1189

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

1190

return 0;

1191

}

1192

1193

struct ifreq ifr;

1194

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

1195

if(debug){

1196

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

1197

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

1198

}

1199

return 0;

1200

}

1201

1202

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

1203

return 0;

1204

}

1205

return 1;

1206

}

1207

1208

/*

1209

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

1210

* corresponds to an acceptable network device which is up.

1211

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

1212

*/

1213

int up_interface(const struct dirent *if_entry){

1214

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

1215

return 0;

1216

}

1217

1218

struct ifreq ifr;

1219

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

1220

if(debug){

1221

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

1222

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

1223

}

1224

return 0;

1225

}

1226

1227

/* Reject down interfaces */

1228

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

1229

if(debug){

1230

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

1231

if_entry->d_name);

1232

}

1233

return 0;

1234

}

1235

1236

/* Reject non-running interfaces */

1237

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

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

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

1246

return 0;

1189

1247

}

1190

1248

return 1;

1191

1249

}

1201

1259

return 1;

1202

1260

}

1203

1261

1262

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

1263

int runnable_hook(const struct dirent *direntry){

1264

int ret;

1265

size_t sret;

1266

struct stat st;

1267

1268

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

1269

/* Empty name? */

1270

return 0;

1271

}

1272

1273

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

1274

"abcdefghijklmnopqrstuvwxyz"

1275

"0123456789"

1276

"_-");

1277

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

1278

/* Contains non-allowed characters */

1279

if(debug){

1280

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

1281

direntry->d_name);

1282

}

1283

return 0;

1284

}

1285

1286

char *fullname = NULL;

1287

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

1288

if(ret < 0){

1289

perror_plus("asprintf");

1290

return 0;

1291

}

1292

1293

ret = stat(fullname, &st);

1294

if(ret == -1){

1295

if(debug){

1296

perror_plus("Could not stat hook");

1297

}

1298

return 0;

1299

}

1300

if(not (S_ISREG(st.st_mode))){

1301

/* Not a regular file */

1302

if(debug){

1303

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

1304

direntry->d_name);

1305

}

1306

return 0;

1307

}

1308

if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){

1309

/* Not executable */

1310

if(debug){

1311

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

1312

direntry->d_name);

1313

}

1314

return 0;

1315

}

1316

if(debug){

1317

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

1318

direntry->d_name);

1319

}

1320

return 1;

1321

}

1322

1204

1323

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1205

1324

int ret;

1206

1325

struct timespec now;

1210

1329

while(true){

1211

1330

if(mc.current_server == NULL){

1212

1331

if (debug){

1213

fprintf(stderr,

1214

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

1332

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

1333

" No timeout!\n");

1215

1334

}

1216

1335

ret = avahi_simple_poll_iterate(s, -1);

1217

1336

} else {

1218

1337

if (debug){

1219

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

1220

" or wait\n");

1338

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

1339

" it, or wait\n");

1221

1340

}

1222

1341

/* the current time */

1223

1342

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1239

1358

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

1240

1359

1241

1360

if (debug){

1242

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

1361

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

1362

block_time);

1243

1363

}

1244

1364

1245

1365

if(block_time <= 0){

1265

1385

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

1266

1386

}

1267

1387

if(ret != 0){

1268

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

1388

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

1269

1389

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

1270

1390

}

1271

1391

}

1272

1392

}

1273

1393

}

1274

1394

1395

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

1396

error_t raise_privileges(void){

1397

error_t old_errno = errno;

1398

error_t ret_errno = 0;

1399

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

1400

ret_errno = errno;

1401

perror_plus("seteuid");

1402

}

1403

errno = old_errno;

1404

return ret_errno;

1405

}

1406

1407

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

1408

error_t raise_privileges_permanently(void){

1409

error_t old_errno = errno;

1410

error_t ret_errno = raise_privileges();

1411

if(ret_errno != 0){

1412

errno = old_errno;

1413

return ret_errno;

1414

}

1415

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

1416

ret_errno = errno;

1417

perror_plus("seteuid");

1418

}

1419

errno = old_errno;

1420

return ret_errno;

1421

}

1422

1423

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

1424

error_t lower_privileges(void){

1425

error_t old_errno = errno;

1426

error_t ret_errno = 0;

1427

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

1428

ret_errno = errno;

1429

perror_plus("seteuid");

1430

}

1431

errno = old_errno;

1432

return ret_errno;

1433

}

1434

1435

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

1436

const float delay){

1437

struct dirent **direntries;

1438

struct dirent *direntry;

1439

int ret;

1440

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

1441

alphasort);

1442

if(numhooks == -1){

1443

perror_plus("scandir");

1444

} else {

1445

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

1446

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

1447

direntry = direntries[i];

1448

char *fullname = NULL;

1449

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

1450

if(ret < 0){

1451

perror_plus("asprintf");

1452

continue;

1453

}

1454

if(debug){

1455

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

1456

direntry->d_name);

1457

}

1458

pid_t hook_pid = fork();

1459

if(hook_pid == 0){

1460

/* Child */

1461

/* Raise privileges */

1462

raise_privileges_permanently();

1463

/* Set group */

1464

errno = 0;

1465

ret = setgid(0);

1466

if(ret == -1){

1467

perror_plus("setgid");

1468

}

1469

/* Reset supplementary groups */

1470

errno = 0;

1471

ret = setgroups(0, NULL);

1472

if(ret == -1){

1473

perror_plus("setgroups");

1474

}

1475

dup2(devnull, STDIN_FILENO);

1476

close(devnull);

1477

dup2(STDERR_FILENO, STDOUT_FILENO);

1478

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

1479

if(ret == -1){

1480

perror_plus("setenv");

1481

_exit(EX_OSERR);

1482

}

1483

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

1484

if(ret == -1){

1485

perror_plus("setenv");

1486

_exit(EX_OSERR);

1487

}

1488

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

1489

if(ret == -1){

1490

perror_plus("setenv");

1491

_exit(EX_OSERR);

1492

}

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

char *delaystring;

1499

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

1500

if(ret == -1){

1501

perror_plus("asprintf");

1502

_exit(EX_OSERR);

1503

}

1504

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

1505

if(ret == -1){

1506

free(delaystring);

1507

perror_plus("setenv");

1508

_exit(EX_OSERR);

1509

}

1510

free(delaystring);

1511

if(connect_to != NULL){

1512

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

1513

if(ret == -1){

1514

perror_plus("setenv");

1515

_exit(EX_OSERR);

1516

}

1517

}

1518

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

1519

perror_plus("execl");

1520

_exit(EXIT_FAILURE);

1521

}

1522

} else {

1523

int status;

1524

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

1525

perror_plus("waitpid");

1526

free(fullname);

1527

continue;

1528

}

1529

if(WIFEXITED(status)){

1530

if(WEXITSTATUS(status) != 0){

1531

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

1532

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

1533

WEXITSTATUS(status));

1534

free(fullname);

1535

continue;

1536

}

1537

} else if(WIFSIGNALED(status)){

1538

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

1539

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

1540

WTERMSIG(status));

1541

free(fullname);

1542

continue;

1543

} else {

1544

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

1545

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

1546

free(fullname);

1547

continue;

1548

}

1549

}

1550

free(fullname);

1551

if(debug){

1552

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

1553

direntry->d_name);

1554

}

1555

}

1556

close(devnull);

1557

}

1558

return true;

1559

}

1560

1561

int bring_up_interface(const char *const interface,

1562

const float delay){

1563

int sd = -1;

1564

int old_errno = errno;

1565

int ret_errno = 0;

1566

int ret;

1567

struct ifreq network;

1568

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

1569

if(if_index == 0){

1570

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

1571

errno = old_errno;

1572

return ENXIO;

1573

}

1574

1575

if(quit_now){

1576

errno = old_errno;

1577

return EINTR;

1578

}

1579

1580

/* Re-raise priviliges */

1581

raise_privileges();

1582

1583

#ifdef __linux__

1584

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1585

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

1586

ret = klogctl(8, NULL, 5);

1587

bool restore_loglevel = true;

1588

if(ret == -1){

1589

restore_loglevel = false;

1590

perror_plus("klogctl");

1591

}

1592

#endif /* __linux__ */

1593

1594

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1595

if(sd < 0){

1596

ret_errno = errno;

1597

perror_plus("socket");

1598

#ifdef __linux__

1599

if(restore_loglevel){

1600

ret = klogctl(7, NULL, 0);

1601

if(ret == -1){

1602

perror_plus("klogctl");

1603

}

1604

}

1605

#endif /* __linux__ */

1606

/* Lower privileges */

1607

lower_privileges();

1608

errno = old_errno;

1609

return ret_errno;

1610

}

1611

strcpy(network.ifr_name, interface);

1612

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

1613

if(ret == -1){

1614

ret_errno = errno;

1615

perror_plus("ioctl SIOCGIFFLAGS");

1616

#ifdef __linux__

1617

if(restore_loglevel){

1618

ret = klogctl(7, NULL, 0);

1619

if(ret == -1){

1620

perror_plus("klogctl");

1621

}

1622

}

1623

#endif /* __linux__ */

1624

/* Lower privileges */

1625

lower_privileges();

1626

errno = old_errno;

1627

return ret_errno;

1628

}

1629

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

1630

network.ifr_flags |= IFF_UP;

1631

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

1632

if(ret == -1){

1633

ret_errno = errno;

1634

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1635

#ifdef __linux__

1636

if(restore_loglevel){

1637

ret = klogctl(7, NULL, 0);

1638

if(ret == -1){

1639

perror_plus("klogctl");

1640

}

1641

}

1642

#endif /* __linux__ */

1643

/* Lower privileges */

1644

lower_privileges();

1645

errno = old_errno;

1646

return ret_errno;

1647

}

1648

}

1649

/* Sleep checking until interface is running.

1650

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

1651

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

1652

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

1653

if(ret == -1){

1654

perror_plus("ioctl SIOCGIFFLAGS");

1655

} else if(network.ifr_flags & IFF_RUNNING){

1656

break;

1657

}

1658

struct timespec sleeptime = { .tv_nsec = 250000000 };

1659

ret = nanosleep(&sleeptime, NULL);

1660

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

1661

perror_plus("nanosleep");

1662

}

1663

}

1664

/* Close the socket */

1665

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

1666

if(ret == -1){

1667

perror_plus("close");

1668

}

1669

#ifdef __linux__

1670

if(restore_loglevel){

1671

/* Restores kernel loglevel to default */

1672

ret = klogctl(7, NULL, 0);

1673

if(ret == -1){

1674

perror_plus("klogctl");

1675

}

1676

}

1677

#endif /* __linux__ */

1678

/* Lower privileges */

1679

lower_privileges();

1680

errno = old_errno;

1681

return 0;

1682

}

1683

1275

1684

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

1276

1685

AvahiSServiceBrowser *sb = NULL;

1277

1686

int error;

1283

1692

struct ifreq network;

1284

1693

int sd = -1;

1285

1694

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1288

1695

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

1289

1696

bool tempdir_created = false;

1290

1697

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1357

1764

.group = 2 },

1358

1765

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

1359

1766

.arg = "SECONDS",

1360

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

1767

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

1768

.group = 2 },

1769

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

1770

.arg = "DIR",

1771

.doc = "Directory where network hooks are located",

1361

1772

.group = 2 },

1362

1773

/*

1363

1774

* These reproduce what we would get without ARGP_NO_HELP

1417

1828

argp_error(state, "Bad retry interval");

1418

1829

}

1419

1830

break;

1831

case 133: /* --network-hook-dir */

1832

hookdir = arg;

1833

break;

1420

1834

/*

1421

1835

* These reproduce what we would get without ARGP_NO_HELP

1422

1836

*/

1428

1842

argp_state_help(state, state->out_stream,

1429

1843

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1430

1844

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

1431

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

1845

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

1432

1846

exit(argp_err_exit_status);

1433

1847

break;

1434

1848

default:

1461

1875

{

1462

1876

/* Work around Debian bug #633582:

1463

1877

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

1464

struct stat st;

1465

1878

1466

1879

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

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

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

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

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

1880

if(raise_privileges() == 0){

1881

struct stat st;

1882

1883

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

1884

int seckey_fd = open(seckey, O_RDONLY);

1885

if(seckey_fd == -1){

1886

perror_plus("open");

1887

} else {

1888

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

1889

if(ret == -1){

1890

perror_plus("fstat");

1891

} else {

1892

if(S_ISREG(st.st_mode)

1893

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

1894

ret = fchown(seckey_fd, uid, gid);

1895

if(ret == -1){

1896

perror_plus("fchown");

1897

}

1898

}

1899

}

1900

TEMP_FAILURE_RETRY(close(seckey_fd));

1901

}

1902

}

1903

1904

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

1905

int pubkey_fd = open(pubkey, O_RDONLY);

1906

if(pubkey_fd == -1){

1907

perror_plus("open");

1908

} else {

1909

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

1910

if(ret == -1){

1911

perror_plus("fstat");

1912

} else {

1913

if(S_ISREG(st.st_mode)

1914

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

1915

ret = fchown(pubkey_fd, uid, gid);

1916

if(ret == -1){

1917

perror_plus("fchown");

1918

}

1919

}

1920

}

1921

TEMP_FAILURE_RETRY(close(pubkey_fd));

1922

}

1923

}

1924

1925

/* Lower privileges */

1926

errno = 0;

1927

ret = seteuid(uid);

1928

if(ret == -1){

1929

perror_plus("seteuid");

1930

}

1931

}

1932

}

1933

1934

/* Run network hooks */

1935

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

1936

goto end;

1519

1937

}

1520

1938

1521

1939

if(not debug){

1522

1940

avahi_set_log_function(empty_log);

1523

1941

}

1524

1942

1525

1943

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

1526

1944

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1945

/* First look for interfaces that are up */

1946

ret = scandir(sys_class_net, &direntries, up_interface,

1528

1947

alphasort);

1948

if(ret == 0){

1949

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

1950

free(direntries);

1951

ret = scandir(sys_class_net, &direntries, good_interface,

1952

alphasort);

1953

}

1529

1954

if(ret >= 1){

1530

/* Pick the first good interface */

1955

/* Pick the first interface returned */

1531

1956

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

1532

1957

if(debug){

1533

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

1958

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

1534

1959

}

1535

1960

if(interface == NULL){

1536

1961

perror_plus("malloc");

1541

1966

free(direntries);

1542

1967

} else {

1543

1968

free(direntries);

1544

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

1969

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

1545

1970

exitcode = EXIT_FAILURE;

1546

1971

goto end;

1547

1972

}

1553

1978

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

1554

1979

mc.simple_poll = avahi_simple_poll_new();

1555

1980

if(mc.simple_poll == NULL){

1556

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

1981

fprintf_plus(stderr,

1982

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

1557

1983

exitcode = EX_UNAVAILABLE;

1558

1984

goto end;

1559

1985

}

1622

2048

}

1623

2049

1624

2050

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

perror_plus("klogctl");

1709

}

1710

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

break;

1729

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

2051

if((interface[0] != '\0') and (strcmp(interface, "none") != 0)){

2052

ret = bring_up_interface(interface, delay);

2053

if(ret != 0){

2054

errno = ret;

2055

perror_plus("Failed to bring up interface");

1766

2056

}

1767

2057

}

1768

2058

1772

2062

1773

2063

ret = init_gnutls_global(pubkey, seckey);

1774

2064

if(ret == -1){

1775

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

2065

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

1776

2066

exitcode = EX_UNAVAILABLE;

1777

2067

goto end;

1778

2068

} else {

1794

2084

}

1795

2085

1796

2086

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

1797

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

2087

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

1798

2088

exitcode = EX_UNAVAILABLE;

1799

2089

goto end;

1800

2090

} else {

1809

2099

/* Connect directly, do not use Zeroconf */

1810

2100

/* (Mainly meant for debugging) */

1811

2101

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

2102

1812

2103

if(address == NULL){

1813

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

2104

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

1814

2105

exitcode = EX_USAGE;

1815

2106

goto end;

1816

2107

}

1824

2115

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

1825

2116

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

1826

2117

or tmpmax != (uint16_t)tmpmax){

1827

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

2118

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

1828

2119

exitcode = EX_USAGE;

1829

2120

goto end;

1830

2121

}

1860

2151

break;

1861

2152

}

1862

2153

if(debug){

1863

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

1864

(int)retry_interval);

2154

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

2155

(int)retry_interval);

1865

2156

}

1866

2157

sleep((int)retry_interval);

1867

2158

}

1869

2160

if (not quit_now){

1870

2161

exitcode = EXIT_SUCCESS;

1871

2162

}

1872

2163

1873

2164

goto end;

1874

2165

}

1875

2166

1897

2188

1898

2189

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

1899

2190

if(mc.server == NULL){

1900

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

1901

avahi_strerror(error));

2191

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

2192

avahi_strerror(error));

1902

2193

exitcode = EX_UNAVAILABLE;

1903

2194

goto end;

1904

2195

}

1912

2203

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1913

2204

NULL, 0, browse_callback, NULL);

1914

2205

if(sb == NULL){

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

2206

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

2207

avahi_strerror(avahi_server_errno(mc.server)));

1917

2208

exitcode = EX_UNAVAILABLE;

1918

2209

goto end;

1919

2210

}

1925

2216

/* Run the main loop */

1926

2217

1927

2218

if(debug){

1928

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

2219

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

1929

2220

}

1930

2221

1931

2222

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

2223

(int)(retry_interval * 1000));

1933

2224

if(debug){

1934

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

1935

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

2225

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

2226

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

1936

2227

}

1937

2228

1938

2229

end:

1939

2230

1940

2231

if(debug){

1941

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

2232

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

1942

2233

}

1943

2234

1944

2235

/* Cleanup things */

1960

2251

if(gpgme_initialized){

1961

2252

gpgme_release(mc.ctx);

1962

2253

}

1963

2254

1964

2255

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

1965

2256

has seen */

1966

2257

if(mc.current_server != NULL){

1972

2263

}

1973

2264

}

1974

2265

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

if(geteuid() == 0){

2266

/* Run network hooks */

2267

run_network_hooks("stop", interface, delay);

2268

2269

/* Re-raise priviliges */

2270

{

2271

raise_privileges();

2272

2273

/* Take down the network interface */

2274

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

1984

2275

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

1985

2276

if(ret == -1){

1986

2277

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

2278

} else if(network.ifr_flags & IFF_UP){

1988

2279

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

1989

2280

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

1990

2281

if(ret == -1){

1995

2286

if(ret == -1){

1996

2287

perror_plus("close");

1997

2288

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

2004

2289

}

2005

2290

}

2291

/* Lower privileges permanently */

2292

errno = 0;

2293

ret = setuid(uid);

2294

if(ret == -1){

2295

perror_plus("setuid");

2296

}

2006

2297

2007

2298

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

2008

2299

if(tempdir_created){

2022

2313

}

2023

2314

ret = remove(fullname);

2024

2315

if(ret == -1){

2025

fprintf(stderr, "remove(\"%s\"): %s\n", fullname,

2026

strerror(errno));

2316

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

2317

strerror(errno));

2027

2318

}

2028

2319

free(fullname);

2029

2320

}