/mandos/release : revision 311

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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

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* 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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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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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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strtoimax() */

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

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

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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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#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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141

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

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char *connect_to = NULL;

137

143

const char *hookdir = HOOKDIR;

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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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uint16_t port;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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157

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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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AvahiServer *server;

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161

gnutls_certificate_credentials_t cred;

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162

unsigned int dh_bits;

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164

const char *priority;

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165

gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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

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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 };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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173

168

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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171

177

/* Function to use when printing errors */

172

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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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181

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

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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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190

182

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

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192

program_invocation_short_name));

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

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

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}

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/*

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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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200

*/

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__attribute__((nonnull, warn_unused_result))

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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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if(buffer_length + BUFFER_SIZE > buffer_capacity){

195

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

196

if(buffer == NULL){

205

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

206

if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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}

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

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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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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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223

int ret;

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

209

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if(new_server == NULL){

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perror_plus("strdup");

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return false;

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236

}

237

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

238

if(ret == -1){

239

perror_plus("clock_gettime");

240

return false;

241

}

221

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/* Special case of first server */

222

if (mc.current_server == NULL){

243

if(*current_server == NULL){

223

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new_server->next = new_server;

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245

new_server->prev = new_server;

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mc.current_server = new_server;

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

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*current_server = new_server;

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247

} else {

228

new_server->next = mc.current_server;

229

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

248

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

249

new_server->next = *current_server;

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

230

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new_server->prev->next = new_server;

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mc.current_server->prev = new_server;

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}

233

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

234

if(ret == -1){

235

perror_plus("clock_gettime");

236

return false;

252

(*current_server)->prev = new_server;

237

253

}

238

254

return true;

239

255

}

241

257

/*

242

258

* Initialize GPGME.

243

259

*/

244

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

245

const char *tempdir){

260

__attribute__((nonnull, warn_unused_result))

261

static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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gpgme_error_t rc;

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266

gpgme_engine_info_t engine_info;

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250

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/*

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269

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

252

270

*/

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bool import_key(const char *filename){

271

bool import_key(const char * const filename){

254

272

int ret;

255

273

int fd;

256

274

gpgme_data_t pgp_data;

268

286

return false;

269

287

}

270

288

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rc = gpgme_op_import(mc.ctx, pgp_data);

289

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

272

290

if(rc != GPG_ERR_NO_ERROR){

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291

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

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292

gpgme_strsource(rc), gpgme_strerror(rc));

318

336

}

319

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320

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/* Create new GPGME "context" */

321

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

339

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

322

340

if(rc != GPG_ERR_NO_ERROR){

323

341

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

324

342

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

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355

* Decrypt OpenPGP data.

338

356

* Returns -1 on error

339

357

*/

358

__attribute__((nonnull, warn_unused_result))

340

359

static ssize_t pgp_packet_decrypt(const char *cryptotext,

341

360

size_t crypto_size,

342

char **plaintext){

361

char **plaintext,

362

mandos_context *mc){

343

363

gpgme_data_t dh_crypto, dh_plain;

344

364

gpgme_error_t rc;

345

365

ssize_t ret;

371

391

372

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

373

393

data buffer */

374

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

394

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

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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plaintext_length = -1;

379

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if(debug){

380

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gpgme_decrypt_result_t result;

381

result = gpgme_op_decrypt_result(mc.ctx);

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result = gpgme_op_decrypt_result(mc->ctx);

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if(result == NULL){

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403

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

384

404

} else {

461

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return plaintext_length;

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482

}

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static const char * safer_gnutls_strerror(int value){

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

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-Wunreachable-code */

484

__attribute__((warn_unused_result))

485

static const char *safer_gnutls_strerror(int value){

486

const char *ret = gnutls_strerror(value);

467

487

if(ret == NULL)

468

488

ret = "(unknown)";

469

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return ret;

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490

}

471

491

472

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/* GnuTLS log function callback */

493

__attribute__((nonnull))

473

494

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

474

495

const char* string){

475

496

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

476

497

}

477

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__attribute__((nonnull, warn_unused_result))

478

500

static int init_gnutls_global(const char *pubkeyfilename,

479

const char *seckeyfilename){

501

const char *seckeyfilename,

502

mandos_context *mc){

480

503

int ret;

481

504

482

505

if(debug){

499

522

}

500

523

501

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/* OpenPGP credentials */

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

525

ret = gnutls_certificate_allocate_credentials(&mc->cred);

503

526

if(ret != GNUTLS_E_SUCCESS){

504

527

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

505

528

safer_gnutls_strerror(ret));

515

538

}

516

539

517

540

ret = gnutls_certificate_set_openpgp_key_file

518

(mc.cred, pubkeyfilename, seckeyfilename,

541

(mc->cred, pubkeyfilename, seckeyfilename,

519

542

GNUTLS_OPENPGP_FMT_BASE64);

520

543

if(ret != GNUTLS_E_SUCCESS){

521

544

fprintf_plus(stderr,

527

550

}

528

551

529

552

/* GnuTLS server initialization */

530

ret = gnutls_dh_params_init(&mc.dh_params);

553

ret = gnutls_dh_params_init(&mc->dh_params);

531

554

if(ret != GNUTLS_E_SUCCESS){

532

555

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

533

556

" initialization: %s\n",

534

557

safer_gnutls_strerror(ret));

535

558

goto globalfail;

536

559

}

537

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

560

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

538

561

if(ret != GNUTLS_E_SUCCESS){

539

562

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

540

563

safer_gnutls_strerror(ret));

541

564

goto globalfail;

542

565

}

543

566

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

567

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

545

568

546

569

return 0;

547

570

548

571

globalfail:

549

572

550

gnutls_certificate_free_credentials(mc.cred);

573

gnutls_certificate_free_credentials(mc->cred);

551

574

gnutls_global_deinit();

552

gnutls_dh_params_deinit(mc.dh_params);

575

gnutls_dh_params_deinit(mc->dh_params);

553

576

return -1;

554

577

}

555

578

556

static int init_gnutls_session(gnutls_session_t *session){

579

__attribute__((nonnull, warn_unused_result))

580

static int init_gnutls_session(gnutls_session_t *session,

581

mandos_context *mc){

557

582

int ret;

558

583

/* GnuTLS session creation */

559

584

do {

571

596

{

572

597

const char *err;

573

598

do {

574

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

599

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

575

600

if(quit_now){

576

601

gnutls_deinit(*session);

577

602

return -1;

588

613

589

614

do {

590

615

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

591

mc.cred);

616

mc->cred);

592

617

if(quit_now){

593

618

gnutls_deinit(*session);

594

619

return -1;

604

629

/* ignore client certificate if any. */

605

630

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

606

631

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

632

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

608

633

609

634

return 0;

610

635

}

614

639

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

615

640

616

641

/* Called when a Mandos server is found */

617

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

642

__attribute__((nonnull, warn_unused_result))

643

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

618

644

AvahiIfIndex if_index,

619

int af){

645

int af, mandos_context *mc){

620

646

int ret, tcp_sd = -1;

621

647

ssize_t sret;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

648

struct sockaddr_storage to;

626

649

char *buffer = NULL;

627

650

char *decrypted_buffer = NULL;

628

651

size_t buffer_length = 0;

652

675

return -1;

653

676

}

654

677

655

ret = init_gnutls_session(&session);

678

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

679

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

680

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

681

bool match = false;

682

{

683

char *interface = NULL;

684

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

685

interface))){

686

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

687

match = true;

688

break;

689

}

690

}

691

}

692

if(not match){

693

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

694

connect to the server */

695

if(debug){

696

char interface[IF_NAMESIZE];

697

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

698

perror_plus("if_indextoname");

699

} else {

700

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

701

" \"%s\"\n",

702

if_indextoname((unsigned int)if_index,

703

interface));

704

}

705

}

706

return -1;

707

}

708

}

709

710

ret = init_gnutls_session(&session, mc);

656

711

if(ret != 0){

657

712

return -1;

658

713

}

659

714

660

715

if(debug){

661

716

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

662

PRIu16 "\n", ip, port);

717

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

663

718

}

664

719

665

720

tcp_sd = socket(pf, SOCK_STREAM, 0);

677

732

678

733

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

679

734

if(af == AF_INET6){

680

to.in6.sin6_family = (sa_family_t)af;

681

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

735

((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;

736

ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);

682

737

} else { /* IPv4 */

683

to.in.sin_family = (sa_family_t)af;

684

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

738

((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;

739

ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);

685

740

}

686

741

if(ret < 0 ){

687

742

int e = errno;

696

751

goto mandos_end;

697

752

}

698

753

if(af == AF_INET6){

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

754

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

755

if(IN6_IS_ADDR_LINKLOCAL

756

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

706

757

if(if_index == AVAHI_IF_UNSPEC){

707

758

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

708

759

" incomplete without a network interface\n");

710

761

goto mandos_end;

711

762

}

712

763

/* Set the network interface number as scope */

713

to.in6.sin6_scope_id = (uint32_t)if_index;

764

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

714

765

}

715

766

} else {

716

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

717

-Wconversion and

718

-Wunreachable-code */

767

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

719

768

}

720

769

721

770

if(quit_now){

729

778

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

730

779

perror_plus("if_indextoname");

731

780

} else {

732

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

733

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

781

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

782

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

734

783

}

735

784

} else {

736

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

737

ip, port);

785

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

786

ip, (uintmax_t)port);

738

787

}

739

788

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

740

789

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

741

const char *pcret;

742

790

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

791

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

792

sizeof(struct sockaddr_in6),

793

addrstr, sizeof(addrstr), NULL, 0,

794

NI_NUMERICHOST);

745

795

} else {

746

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

747

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

748

800

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

801

if(ret == EAI_SYSTEM){

802

perror_plus("getnameinfo");

803

} else if(ret != 0) {

804

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

805

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

806

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

755

807

}

756

808

}

757

809

761

813

}

762

814

763

815

if(af == AF_INET6){

764

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

816

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

817

sizeof(struct sockaddr_in6));

765

818

} else {

766

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

819

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

820

sizeof(struct sockaddr_in));

767

821

}

768

822

if(ret < 0){

769

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

823

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

770

824

int e = errno;

771

825

perror_plus("connect");

772

826

errno = e;

818

872

goto mandos_end;

819

873

}

820

874

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

875

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

876

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

877

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

878

gnutls_transport_set_ptr(session,

879

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

823

880

824

881

if(quit_now){

825

882

errno = EINTR;

930

987

if(buffer_length > 0){

931

988

ssize_t decrypted_buffer_size;

932

989

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

933

&decrypted_buffer);

990

&decrypted_buffer, mc);

934

991

if(decrypted_buffer_size >= 0){

935

992

936

993

written = 0;

984

1041

return retval;

985

1042

}

986

1043

1044

__attribute__((nonnull))

987

1045

static void resolve_callback(AvahiSServiceResolver *r,

988

1046

AvahiIfIndex interface,

989

1047

AvahiProtocol proto,

997

1055

AVAHI_GCC_UNUSED AvahiStringList *txt,

998

1056

AVAHI_GCC_UNUSED AvahiLookupResultFlags

999

1057

flags,

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1058

void *mc){

1059

if(r == NULL){

1060

return;

1061

}

1002

1062

1003

1063

/* Called whenever a service has been resolved successfully or

1004

1064

timed out */

1013

1073

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

1014

1074

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

1015

1075

domain,

1016

avahi_strerror(avahi_server_errno(mc.server)));

1076

avahi_strerror(avahi_server_errno

1077

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

1017

1078

break;

1018

1079

1019

1080

case AVAHI_RESOLVER_FOUND:

1025

1086

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

1026

1087

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

1027

1088

}

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1089

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

1090

interface,

1091

avahi_proto_to_af(proto),

1092

mc);

1030

1093

if(ret == 0){

1031

avahi_simple_poll_quit(mc.simple_poll);

1094

avahi_simple_poll_quit(simple_poll);

1032

1095

} else {

1033

if(not add_server(ip, port, interface,

1034

avahi_proto_to_af(proto))){

1096

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

1097

avahi_proto_to_af(proto),

1098

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

1035

1099

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

1036

1100

" list\n", name);

1037

1101

}

1050

1114

const char *domain,

1051

1115

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1052

1116

flags,

1053

AVAHI_GCC_UNUSED void* userdata){

1054

assert(b);

1117

void *mc){

1118

if(b == NULL){

1119

return;

1120

}

1055

1121

1056

1122

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

1057

1123

is removed from the LAN */

1065

1131

case AVAHI_BROWSER_FAILURE:

1066

1132

1067

1133

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

1068

avahi_strerror(avahi_server_errno(mc.server)));

1069

avahi_simple_poll_quit(mc.simple_poll);

1134

avahi_strerror(avahi_server_errno

1135

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

1136

avahi_simple_poll_quit(simple_poll);

1070

1137

return;

1071

1138

1072

1139

case AVAHI_BROWSER_NEW:

1075

1142

the callback function is called the Avahi server will free the

1076

1143

resolver for us. */

1077

1144

1078

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

1079

name, type, domain, protocol, 0,

1080

resolve_callback, NULL) == NULL)

1145

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

1146

interface, protocol, name, type,

1147

domain, protocol, 0,

1148

resolve_callback, mc) == NULL)

1081

1149

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

1082

1150

" %s\n", name,

1083

avahi_strerror(avahi_server_errno(mc.server)));

1151

avahi_strerror(avahi_server_errno

1152

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

1084

1153

break;

1085

1154

1086

1155

case AVAHI_BROWSER_REMOVE:

1105

1174

signal_received = sig;

1106

1175

int old_errno = errno;

1107

1176

/* set main loop to exit */

1108

if(mc.simple_poll != NULL){

1109

avahi_simple_poll_quit(mc.simple_poll);

1177

if(simple_poll != NULL){

1178

avahi_simple_poll_quit(simple_poll);

1110

1179

}

1111

1180

errno = old_errno;

1112

1181

}

1113

1182

1183

__attribute__((nonnull, warn_unused_result))

1114

1184

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

1115

1185

int ret;

1186

error_t ret_errno;

1116

1187

1117

1188

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

1118

1189

if(s < 0){

1190

ret_errno = errno;

1119

1191

perror_plus("socket");

1192

errno = ret_errno;

1120

1193

return false;

1121

1194

}

1122

1195

strcpy(ifr->ifr_name, ifname);

1123

1196

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1124

1197

if(ret == -1){

1125

1198

if(debug){

1199

ret_errno = errno;

1126

1200

perror_plus("ioctl SIOCGIFFLAGS");

1201

errno = ret_errno;

1127

1202

}

1128

1203

return false;

1129

1204

}

1130

1205

return true;

1131

1206

}

1132

1207

1208

__attribute__((nonnull, warn_unused_result))

1133

1209

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

1134

1210

1135

1211

/* Reject the loopback device */

1177

1253

* corresponds to an acceptable network device.

1178

1254

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

1179

1255

*/

1256

__attribute__((nonnull, warn_unused_result))

1180

1257

int good_interface(const struct dirent *if_entry){

1181

1258

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

1182

1259

return 0;

1198

1275

}

1199

1276

1200

1277

/*

1201

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

1202

* corresponds to an acceptable network device which is up.

1203

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

1204

*/

1205

int up_interface(const struct dirent *if_entry){

1206

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

1207

return 0;

1208

}

1209

1210

struct ifreq ifr;

1211

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

1212

if(debug){

1213

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

1214

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

1215

}

1216

return 0;

1217

}

1218

1219

/* Reject down interfaces */

1220

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

1221

if(debug){

1222

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

1223

if_entry->d_name);

1224

}

1225

return 0;

1226

}

1227

1228

/* Reject non-running interfaces */

1229

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

1230

if(debug){

1231

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

1232

if_entry->d_name);

1233

}

1234

return 0;

1235

}

1236

1237

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

1238

return 0;

1239

}

1240

return 1;

1241

}

1242

1278

* This function determines if a network interface is up.

1279

*/

1280

__attribute__((nonnull, warn_unused_result))

1281

bool interface_is_up(const char *interface){

1282

struct ifreq ifr;

1283

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

1284

if(debug){

1285

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

1286

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

1287

}

1288

return false;

1289

}

1290

1291

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

1292

}

1293

1294

/*

1295

* This function determines if a network interface is running

1296

*/

1297

__attribute__((nonnull, warn_unused_result))

1298

bool interface_is_running(const char *interface){

1299

struct ifreq ifr;

1300

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

1301

if(debug){

1302

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

1303

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

1304

}

1305

return false;

1306

}

1307

1308

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

1309

}

1310

1311

__attribute__((nonnull, pure, warn_unused_result))

1243

1312

int notdotentries(const struct dirent *direntry){

1244

1313

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

1245

1314

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

1252

1321

}

1253

1322

1254

1323

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

1324

__attribute__((nonnull, warn_unused_result))

1255

1325

int runnable_hook(const struct dirent *direntry){

1256

1326

int ret;

1257

1327

size_t sret;

1312

1382

return 1;

1313

1383

}

1314

1384

1315

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1385

__attribute__((nonnull, warn_unused_result))

1386

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1387

mandos_context *mc){

1316

1388

int ret;

1317

1389

struct timespec now;

1318

1390

struct timespec waited_time;

1319

1391

intmax_t block_time;

1320

1392

1321

1393

while(true){

1322

if(mc.current_server == NULL){

1323

if (debug){

1394

if(mc->current_server == NULL){

1395

if(debug){

1324

1396

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

1325

1397

" No timeout!\n");

1326

1398

}

1327

1399

ret = avahi_simple_poll_iterate(s, -1);

1328

1400

} else {

1329

if (debug){

1401

if(debug){

1330

1402

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

1331

1403

" it, or wait\n");

1332

1404

}

1339

1411

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

1340

1412

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

1341

1413

waited_time.tv_sec = (now.tv_sec

1342

- mc.current_server->last_seen.tv_sec);

1414

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

1343

1415

waited_time.tv_nsec = (now.tv_nsec

1344

- mc.current_server->last_seen.tv_nsec);

1416

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

1345

1417

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

1346

1418

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

1347

1419

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

1349

1421

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

1350

1422

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

1351

1423

1352

if (debug){

1424

if(debug){

1353

1425

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

1354

1426

block_time);

1355

1427

}

1356

1428

1357

1429

if(block_time <= 0){

1358

ret = start_mandos_communication(mc.current_server->ip,

1359

mc.current_server->port,

1360

mc.current_server->if_index,

1361

mc.current_server->af);

1430

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

1431

mc->current_server->port,

1432

mc->current_server->if_index,

1433

mc->current_server->af, mc);

1362

1434

if(ret == 0){

1363

avahi_simple_poll_quit(mc.simple_poll);

1435

avahi_simple_poll_quit(s);

1364

1436

return 0;

1365

1437

}

1366

1438

ret = clock_gettime(CLOCK_MONOTONIC,

1367

&mc.current_server->last_seen);

1439

&mc->current_server->last_seen);

1368

1440

if(ret == -1){

1369

1441

perror_plus("clock_gettime");

1370

1442

return -1;

1371

1443

}

1372

mc.current_server = mc.current_server->next;

1444

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

1373

1445

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

1374

1446

servers, but don't block */

1375

1447

}

1377

1449

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

1378

1450

}

1379

1451

if(ret != 0){

1380

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

1452

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

1381

1453

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

1382

1454

}

1383

1455

}

1384

1456

}

1385

1457

}

1386

1458

1387

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

1459

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

1460

__attribute__((warn_unused_result))

1461

error_t raise_privileges(void){

1462

error_t old_errno = errno;

1463

error_t ret_errno = 0;

1464

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

1465

ret_errno = errno;

1466

perror_plus("seteuid");

1467

}

1468

errno = old_errno;

1469

return ret_errno;

1470

}

1471

1472

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

1473

__attribute__((warn_unused_result))

1474

error_t raise_privileges_permanently(void){

1475

error_t old_errno = errno;

1476

error_t ret_errno = raise_privileges();

1477

if(ret_errno != 0){

1478

errno = old_errno;

1479

return ret_errno;

1480

}

1481

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

1482

ret_errno = errno;

1483

perror_plus("seteuid");

1484

}

1485

errno = old_errno;

1486

return ret_errno;

1487

}

1488

1489

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

1490

__attribute__((warn_unused_result))

1491

error_t lower_privileges(void){

1492

error_t old_errno = errno;

1493

error_t ret_errno = 0;

1494

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

1495

ret_errno = errno;

1496

perror_plus("seteuid");

1497

}

1498

errno = old_errno;

1499

return ret_errno;

1500

}

1501

1502

/* Lower privileges permanently */

1503

__attribute__((warn_unused_result))

1504

error_t lower_privileges_permanently(void){

1505

error_t old_errno = errno;

1506

error_t ret_errno = 0;

1507

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

1508

ret_errno = errno;

1509

perror_plus("setuid");

1510

}

1511

errno = old_errno;

1512

return ret_errno;

1513

}

1514

1515

__attribute__((nonnull))

1516

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

1388

1517

const float delay){

1389

1518

struct dirent **direntries;

1390

struct dirent *direntry;

1391

int ret;

1392

1519

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

1393

1520

alphasort);

1394

1521

if(numhooks == -1){

1395

perror_plus("scandir");

1522

if(errno == ENOENT){

1523

if(debug){

1524

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

1525

" found\n", hookdir);

1526

}

1527

} else {

1528

perror_plus("scandir");

1529

}

1396

1530

} else {

1531

struct dirent *direntry;

1532

int ret;

1397

1533

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

1398

1534

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

1399

1535

direntry = direntries[i];

1411

1547

if(hook_pid == 0){

1412

1548

/* Child */

1413

1549

/* Raise privileges */

1414

errno = 0;

1415

ret = seteuid(0);

1416

if(ret == -1){

1417

perror_plus("seteuid");

1418

}

1419

/* Raise privileges even more */

1420

errno = 0;

1421

ret = setuid(0);

1422

if(ret == -1){

1423

perror_plus("setuid");

1550

if(raise_privileges_permanently() != 0){

1551

perror_plus("Failed to raise privileges");

1552

_exit(EX_NOPERM);

1424

1553

}

1425

1554

/* Set group */

1426

1555

errno = 0;

1427

1556

ret = setgid(0);

1428

1557

if(ret == -1){

1429

1558

perror_plus("setgid");

1559

_exit(EX_NOPERM);

1430

1560

}

1431

1561

/* Reset supplementary groups */

1432

1562

errno = 0;

1433

1563

ret = setgroups(0, NULL);

1434

1564

if(ret == -1){

1435

1565

perror_plus("setgroups");

1436

}

1437

dup2(devnull, STDIN_FILENO);

1438

close(devnull);

1439

dup2(STDERR_FILENO, STDOUT_FILENO);

1566

_exit(EX_NOPERM);

1567

}

1568

ret = dup2(devnull, STDIN_FILENO);

1569

if(ret == -1){

1570

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

1571

_exit(EX_OSERR);

1572

}

1573

ret = close(devnull);

1574

if(ret == -1){

1575

perror_plus("close");

1576

_exit(EX_OSERR);

1577

}

1578

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1579

if(ret == -1){

1580

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

1581

_exit(EX_OSERR);

1582

}

1440

1583

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

1441

1584

if(ret == -1){

1442

1585

perror_plus("setenv");

1447

1590

perror_plus("setenv");

1448

1591

_exit(EX_OSERR);

1449

1592

}

1450

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

1593

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

1451

1594

if(ret == -1){

1452

1595

perror_plus("setenv");

1453

1596

_exit(EX_OSERR);

1458

1601

_exit(EX_OSERR);

1459

1602

}

1460

1603

char *delaystring;

1461

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

1604

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

1462

1605

if(ret == -1){

1463

1606

perror_plus("asprintf");

1464

1607

_exit(EX_OSERR);

1470

1613

_exit(EX_OSERR);

1471

1614

}

1472

1615

free(delaystring);

1473

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

1474

perror_plus("execl");

1616

if(connect_to != NULL){

1617

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

1618

if(ret == -1){

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

}

1623

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

1624

perror_plus("execl");

1625

_exit(EXIT_FAILURE);

1626

}

1475

1627

} else {

1476

1628

int status;

1477

1629

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

1508

1660

}

1509

1661

close(devnull);

1510

1662

}

1511

return true;

1663

}

1664

1665

__attribute__((nonnull, warn_unused_result))

1666

error_t bring_up_interface(const char *const interface,

1667

const float delay){

1668

error_t old_errno = errno;

1669

int ret;

1670

struct ifreq network;

1671

unsigned int if_index = if_nametoindex(interface);

1672

if(if_index == 0){

1673

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

1674

errno = old_errno;

1675

return ENXIO;

1676

}

1677

1678

if(quit_now){

1679

errno = old_errno;

1680

return EINTR;

1681

}

1682

1683

if(not interface_is_up(interface)){

1684

error_t ret_errno = 0, ioctl_errno = 0;

1685

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

1686

ret_errno = errno;

1687

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

1688

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

1689

errno = old_errno;

1690

return ret_errno;

1691

}

1692

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

1693

1694

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

1695

if(sd == -1){

1696

ret_errno = errno;

1697

perror_plus("socket");

1698

errno = old_errno;

1699

return ret_errno;

1700

}

1701

1702

if(quit_now){

1703

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

1704

if(ret == -1){

1705

perror_plus("close");

1706

}

1707

errno = old_errno;

1708

return EINTR;

1709

}

1710

1711

if(debug){

1712

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

1713

interface);

1714

}

1715

1716

/* Raise privileges */

1717

ret_errno = raise_privileges();

1718

if(ret_errno != 0){

1719

perror_plus("Failed to raise privileges");

1720

}

1721

1722

#ifdef __linux__

1723

int ret_linux;

1724

bool restore_loglevel = false;

1725

if(ret_errno == 0){

1726

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1727

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

1728

ret_linux = klogctl(8, NULL, 5);

1729

if(ret_linux == -1){

1730

perror_plus("klogctl");

1731

} else {

1732

restore_loglevel = true;

1733

}

1734

}

1735

#endif /* __linux__ */

1736

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

1737

ioctl_errno = errno;

1738

#ifdef __linux__

1739

if(restore_loglevel){

1740

ret_linux = klogctl(7, NULL, 0);

1741

if(ret_linux == -1){

1742

perror_plus("klogctl");

1743

}

1744

}

1745

#endif /* __linux__ */

1746

1747

/* If raise_privileges() succeeded above */

1748

if(ret_errno == 0){

1749

/* Lower privileges */

1750

ret_errno = lower_privileges();

1751

if(ret_errno != 0){

1752

errno = ret_errno;

1753

perror_plus("Failed to lower privileges");

1754

}

1755

}

1756

1757

/* Close the socket */

1758

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

1759

if(ret == -1){

1760

perror_plus("close");

1761

}

1762

1763

if(ret_setflags == -1){

1764

errno = ioctl_errno;

1765

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1766

errno = old_errno;

1767

return ioctl_errno;

1768

}

1769

} else if(debug){

1770

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

1771

interface);

1772

}

1773

1774

/* Sleep checking until interface is running.

1775

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

1776

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

1777

if(interface_is_running(interface)){

1778

break;

1779

}

1780

struct timespec sleeptime = { .tv_nsec = 250000000 };

1781

ret = nanosleep(&sleeptime, NULL);

1782

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

1783

perror_plus("nanosleep");

1784

}

1785

}

1786

1787

errno = old_errno;

1788

return 0;

1789

}

1790

1791

__attribute__((nonnull, warn_unused_result))

1792

error_t take_down_interface(const char *const interface){

1793

error_t old_errno = errno;

1794

struct ifreq network;

1795

unsigned int if_index = if_nametoindex(interface);

1796

if(if_index == 0){

1797

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

1798

errno = old_errno;

1799

return ENXIO;

1800

}

1801

if(interface_is_up(interface)){

1802

error_t ret_errno = 0, ioctl_errno = 0;

1803

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

1804

ret_errno = errno;

1805

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

1806

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

1807

errno = old_errno;

1808

return ret_errno;

1809

}

1810

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

1811

1812

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

1813

if(sd == -1){

1814

ret_errno = errno;

1815

perror_plus("socket");

1816

errno = old_errno;

1817

return ret_errno;

1818

}

1819

1820

if(debug){

1821

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

1822

interface);

1823

}

1824

1825

/* Raise privileges */

1826

ret_errno = raise_privileges();

1827

if(ret_errno != 0){

1828

perror_plus("Failed to raise privileges");

1829

}

1830

1831

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

1832

ioctl_errno = errno;

1833

1834

/* If raise_privileges() succeeded above */

1835

if(ret_errno == 0){

1836

/* Lower privileges */

1837

ret_errno = lower_privileges();

1838

if(ret_errno != 0){

1839

errno = ret_errno;

1840

perror_plus("Failed to lower privileges");

1841

}

1842

}

1843

1844

/* Close the socket */

1845

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

1846

if(ret == -1){

1847

perror_plus("close");

1848

}

1849

1850

if(ret_setflags == -1){

1851

errno = ioctl_errno;

1852

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1853

errno = old_errno;

1854

return ioctl_errno;

1855

}

1856

} else if(debug){

1857

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

1858

interface);

1859

}

1860

1861

errno = old_errno;

1862

return 0;

1512

1863

}

1513

1864

1514

1865

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

1866

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

1867

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

1868

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

1869

.interfaces = NULL, .interfaces_size = 0 };

1515

1870

AvahiSServiceBrowser *sb = NULL;

1516

int error;

1871

error_t ret_errno;

1517

1872

int ret;

1518

1873

intmax_t tmpmax;

1519

1874

char *tmp;

1520

1875

int exitcode = EXIT_SUCCESS;

1521

const char *interface = "";

1522

struct ifreq network;

1523

int sd = -1;

1524

bool take_down_interface = false;

1525

uid_t uid;

1526

gid_t gid;

1527

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

1528

bool tempdir_created = false;

1876

char *interfaces_to_take_down = NULL;

1877

size_t interfaces_to_take_down_size = 0;

1878

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

1879

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

1880

char *tempdir = NULL;

1529

1881

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1530

1882

const char *seckey = PATHDIR "/" SECKEY;

1531

1883

const char *pubkey = PATHDIR "/" PUBKEY;

1884

char *interfaces_hooks = NULL;

1532

1885

1533

1886

bool gnutls_initialized = false;

1534

1887

bool gpgme_initialized = false;

1596

1949

.group = 2 },

1597

1950

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

1598

1951

.arg = "SECONDS",

1599

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

1952

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

1600

1953

.group = 2 },

1601

1954

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

1602

1955

.arg = "DIR",

1625

1978

connect_to = arg;

1626

1979

break;

1627

1980

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

1628

interface = arg;

1981

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

1982

arg, (int)',');

1983

if(ret_errno != 0){

1984

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

1985

}

1629

1986

break;

1630

1987

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

1631

1988

seckey = arg;

1708

2065

/* Work around Debian bug #633582:

1709

2066

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

1710

2067

1711

/* Re-raise priviliges */

1712

errno = 0;

1713

ret = seteuid(0);

1714

if(ret == -1){

1715

perror_plus("seteuid");

2068

/* Re-raise privileges */

2069

ret_errno = raise_privileges();

2070

if(ret_errno != 0){

2071

errno = ret_errno;

2072

perror_plus("Failed to raise privileges");

1716

2073

} else {

1717

2074

struct stat st;

1718

2075

1759

2116

}

1760

2117

1761

2118

/* Lower privileges */

1762

errno = 0;

1763

ret = seteuid(uid);

1764

if(ret == -1){

1765

perror_plus("seteuid");

2119

ret_errno = lower_privileges();

2120

if(ret_errno != 0){

2121

errno = ret_errno;

2122

perror_plus("Failed to lower privileges");

2123

}

2124

}

2125

}

2126

2127

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

2128

{

2129

char *interface = NULL;

2130

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

2131

interface))){

2132

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

2133

and if_nametoindex(interface) == 0){

2134

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

2135

fprintf_plus(stderr, "Not using nonexisting interface"

2136

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

2137

}

2138

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

2139

interface = NULL;

1766

2140

}

1767

2141

}

1768

2142

}

1769

2143

1770

2144

/* Run network hooks */

1771

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

1772

goto end;

2145

{

2146

if(mc.interfaces != NULL){

2147

interfaces_hooks = malloc(mc.interfaces_size);

2148

if(interfaces_hooks == NULL){

2149

perror_plus("malloc");

2150

goto end;

2151

}

2152

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

2153

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

2154

}

2155

run_network_hooks("start", interfaces_hooks != NULL ?

2156

interfaces_hooks : "", delay);

1773

2157

}

1774

2158

1775

2159

if(not debug){

1776

2160

avahi_set_log_function(empty_log);

1777

2161

}

1778

2162

1779

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

1780

struct dirent **direntries;

1781

/* First look for interfaces that are up */

1782

ret = scandir(sys_class_net, &direntries, up_interface,

1783

alphasort);

1784

if(ret == 0){

1785

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

1786

free(direntries);

1787

ret = scandir(sys_class_net, &direntries, good_interface,

1788

alphasort);

1789

}

1790

if(ret >= 1){

1791

/* Pick the first interface returned */

1792

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

1793

if(debug){

1794

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

1795

}

1796

if(interface == NULL){

1797

perror_plus("malloc");

1798

free(direntries);

1799

exitcode = EXIT_FAILURE;

1800

goto end;

1801

}

1802

free(direntries);

1803

} else {

1804

free(direntries);

1805

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

1806

exitcode = EXIT_FAILURE;

1807

goto end;

1808

}

1809

}

1810

1811

2163

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

1812

2164

from the signal handler */

1813

2165

/* Initialize the pseudo-RNG for Avahi */

1814

2166

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

1815

mc.simple_poll = avahi_simple_poll_new();

1816

if(mc.simple_poll == NULL){

2167

simple_poll = avahi_simple_poll_new();

2168

if(simple_poll == NULL){

1817

2169

fprintf_plus(stderr,

1818

2170

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

1819

2171

exitcode = EX_UNAVAILABLE;

1883

2235

}

1884

2236

}

1885

2237

1886

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

1887

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

1888

if_index = (AvahiIfIndex) if_nametoindex(interface);

1889

if(if_index == 0){

1890

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

1891

exitcode = EX_UNAVAILABLE;

1892

goto end;

1893

}

1894

1895

if(quit_now){

1896

goto end;

1897

}

1898

1899

/* Re-raise priviliges */

1900

errno = 0;

1901

ret = seteuid(0);

1902

if(ret == -1){

1903

perror_plus("seteuid");

1904

}

1905

1906

#ifdef __linux__

1907

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1908

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

1909

ret = klogctl(8, NULL, 5);

1910

bool restore_loglevel = true;

1911

if(ret == -1){

1912

restore_loglevel = false;

1913

perror_plus("klogctl");

1914

}

1915

#endif /* __linux__ */

1916

1917

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1918

if(sd < 0){

1919

perror_plus("socket");

1920

exitcode = EX_OSERR;

1921

#ifdef __linux__

1922

if(restore_loglevel){

1923

ret = klogctl(7, NULL, 0);

1924

if(ret == -1){

1925

perror_plus("klogctl");

1926

}

1927

}

1928

#endif /* __linux__ */

1929

/* Lower privileges */

1930

errno = 0;

1931

ret = seteuid(uid);

1932

if(ret == -1){

1933

perror_plus("seteuid");

1934

}

1935

goto end;

1936

}

1937

strcpy(network.ifr_name, interface);

1938

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

1939

if(ret == -1){

1940

perror_plus("ioctl SIOCGIFFLAGS");

1941

#ifdef __linux__

1942

if(restore_loglevel){

1943

ret = klogctl(7, NULL, 0);

1944

if(ret == -1){

1945

perror_plus("klogctl");

1946

}

1947

}

1948

#endif /* __linux__ */

1949

exitcode = EX_OSERR;

1950

/* Lower privileges */

1951

errno = 0;

1952

ret = seteuid(uid);

1953

if(ret == -1){

1954

perror_plus("seteuid");

1955

}

1956

goto end;

1957

}

1958

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

1959

network.ifr_flags |= IFF_UP;

1960

take_down_interface = true;

1961

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

1962

if(ret == -1){

1963

take_down_interface = false;

1964

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1965

exitcode = EX_OSERR;

1966

#ifdef __linux__

1967

if(restore_loglevel){

1968

ret = klogctl(7, NULL, 0);

1969

if(ret == -1){

1970

perror_plus("klogctl");

2238

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

2239

if(mc.interfaces == NULL){

2240

struct dirent **direntries;

2241

/* Look for any good interfaces */

2242

ret = scandir(sys_class_net, &direntries, good_interface,

2243

alphasort);

2244

if(ret >= 1){

2245

/* Add all found interfaces to interfaces list */

2246

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

2247

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

2248

direntries[i]->d_name);

2249

if(ret_errno != 0){

2250

errno = ret_errno;

2251

perror_plus("argz_add");

2252

continue;

2253

}

2254

if(debug){

2255

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

2256

direntries[i]->d_name);

2257

}

2258

}

2259

free(direntries);

2260

} else {

2261

free(direntries);

2262

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

2263

exitcode = EXIT_FAILURE;

2264

goto end;

2265

}

2266

}

2267

2268

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

2269

{

2270

char *interface = NULL;

2271

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

2272

interface))){

2273

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

2274

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

2275

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

2276

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

2277

interface);

2278

interface = NULL;

2279

while((interface = argz_next(mc.interfaces,

2280

mc.interfaces_size, interface))){

2281

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

2282

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

2283

interface);

2284

interface = NULL;

1971

2285

}

1972

2286

}

1973

#endif /* __linux__ */

1974

/* Lower privileges */

1975

errno = 0;

1976

ret = seteuid(uid);

1977

if(ret == -1){

1978

perror_plus("seteuid");

1979

}

1980

goto end;

1981

}

1982

}

1983

/* Sleep checking until interface is running.

1984

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

1985

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

1986

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

1987

if(ret == -1){

1988

perror_plus("ioctl SIOCGIFFLAGS");

1989

} else if(network.ifr_flags & IFF_RUNNING){

1990

2287

break;

1991

2288

}

1992

struct timespec sleeptime = { .tv_nsec = 250000000 };

1993

ret = nanosleep(&sleeptime, NULL);

1994

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

1995

perror_plus("nanosleep");

1996

}

1997

}

1998

if(not take_down_interface){

1999

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

2000

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

2001

if(ret == -1){

2002

perror_plus("close");

2003

}

2004

}

2005

#ifdef __linux__

2006

if(restore_loglevel){

2007

/* Restores kernel loglevel to default */

2008

ret = klogctl(7, NULL, 0);

2009

if(ret == -1){

2010

perror_plus("klogctl");

2011

}

2012

}

2013

#endif /* __linux__ */

2014

/* Lower privileges */

2015

errno = 0;

2016

/* Lower privileges */

2017

ret = seteuid(uid);

2018

if(ret == -1){

2019

perror_plus("seteuid");

2020

}

2289

bool interface_was_up = interface_is_up(interface);

2290

errno = bring_up_interface(interface, delay);

2291

if(not interface_was_up){

2292

if(errno != 0){

2293

perror_plus("Failed to bring up interface");

2294

} else {

2295

errno = argz_add(&interfaces_to_take_down,

2296

&interfaces_to_take_down_size,

2297

interface);

2298

if(errno != 0){

2299

perror_plus("argz_add");

2300

}

2301

}

2302

}

2303

}

2304

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

2305

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

2306

}

2307

}

2308

2309

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

2310

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

2311

if(debug){

2312

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

2313

mc.interfaces);

2314

}

2315

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

2021

2316

}

2022

2317

2023

2318

if(quit_now){

2024

2319

goto end;

2025

2320

}

2026

2321

2027

ret = init_gnutls_global(pubkey, seckey);

2322

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

2028

2323

if(ret == -1){

2029

2324

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

2030

2325

exitcode = EX_UNAVAILABLE;

2037

2332

goto end;

2038

2333

}

2039

2334

2040

if(mkdtemp(tempdir) == NULL){

2335

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

2336

tempdir = mkdtemp(run_tempdir);

2337

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

2338

if(debug){

2339

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

2340

run_tempdir, old_tempdir);

2341

}

2342

tempdir = mkdtemp(old_tempdir);

2343

}

2344

if(tempdir == NULL){

2041

2345

perror_plus("mkdtemp");

2042

2346

goto end;

2043

2347

}

2044

tempdir_created = true;

2045

2348

2046

2349

if(quit_now){

2047

2350

goto end;

2048

2351

}

2049

2352

2050

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

2353

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

2051

2354

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

2052

2355

exitcode = EX_UNAVAILABLE;

2053

2356

goto end;

2063

2366

/* Connect directly, do not use Zeroconf */

2064

2367

/* (Mainly meant for debugging) */

2065

2368

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

2369

2066

2370

if(address == NULL){

2067

2371

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

2068

2372

exitcode = EX_USAGE;

2073

2377

goto end;

2074

2378

}

2075

2379

2076

uint16_t port;

2380

in_port_t port;

2077

2381

errno = 0;

2078

2382

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

2079

2383

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

2080

or tmpmax != (uint16_t)tmpmax){

2384

or tmpmax != (in_port_t)tmpmax){

2081

2385

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

2082

2386

exitcode = EX_USAGE;

2083

2387

goto end;

2084

2388

}

2085

2389

2086

2390

if(quit_now){

2087

2391

goto end;

2088

2392

}

2089

2393

2090

port = (uint16_t)tmpmax;

2394

port = (in_port_t)tmpmax;

2091

2395

*address = '\0';

2092

2396

/* Colon in address indicates IPv6 */

2093

2397

int af;

2109

2413

}

2110

2414

2111

2415

while(not quit_now){

2112

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

2416

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

2417

&mc);

2113

2418

if(quit_now or ret == 0){

2114

2419

break;

2115

2420

}

2117

2422

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

2118

2423

(int)retry_interval);

2119

2424

}

2120

sleep((int)retry_interval);

2425

sleep((unsigned int)retry_interval);

2121

2426

}

2122

2427

2123

if (not quit_now){

2428

if(not quit_now){

2124

2429

exitcode = EXIT_SUCCESS;

2125

2430

}

2126

2431

2141

2446

config.publish_domain = 0;

2142

2447

2143

2448

/* Allocate a new server */

2144

mc.server = avahi_server_new(avahi_simple_poll_get

2145

(mc.simple_poll), &config, NULL,

2146

NULL, &error);

2449

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2450

&config, NULL, NULL, &ret_errno);

2147

2451

2148

2452

/* Free the Avahi configuration data */

2149

2453

avahi_server_config_free(&config);

2152

2456

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

2153

2457

if(mc.server == NULL){

2154

2458

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

2155

avahi_strerror(error));

2459

avahi_strerror(ret_errno));

2156

2460

exitcode = EX_UNAVAILABLE;

2157

2461

goto end;

2158

2462

}

2164

2468

/* Create the Avahi service browser */

2165

2469

sb = avahi_s_service_browser_new(mc.server, if_index,

2166

2470

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2167

NULL, 0, browse_callback, NULL);

2471

NULL, 0, browse_callback,

2472

(void *)&mc);

2168

2473

if(sb == NULL){

2169

2474

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

2170

2475

avahi_strerror(avahi_server_errno(mc.server)));

2182

2487

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

2183

2488

}

2184

2489

2185

ret = avahi_loop_with_timeout(mc.simple_poll,

2186

(int)(retry_interval * 1000));

2490

ret = avahi_loop_with_timeout(simple_poll,

2491

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

2187

2492

if(debug){

2188

2493

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

2189

2494

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

2196

2501

}

2197

2502

2198

2503

/* Cleanup things */

2504

free(mc.interfaces);

2505

2199

2506

if(sb != NULL)

2200

2507

avahi_s_service_browser_free(sb);

2201

2508

2202

2509

if(mc.server != NULL)

2203

2510

avahi_server_free(mc.server);

2204

2511

2205

if(mc.simple_poll != NULL)

2206

avahi_simple_poll_free(mc.simple_poll);

2512

if(simple_poll != NULL)

2513

avahi_simple_poll_free(simple_poll);

2207

2514

2208

2515

if(gnutls_initialized){

2209

2516

gnutls_certificate_free_credentials(mc.cred);

2226

2533

}

2227

2534

}

2228

2535

2229

/* Run network hooks */

2230

run_network_hooks("stop", interface, delay);

2231

2232

/* Re-raise priviliges */

2536

/* Re-raise privileges */

2233

2537

{

2234

errno = 0;

2235

ret = seteuid(0);

2236

if(ret == -1){

2237

perror_plus("seteuid");

2538

ret_errno = raise_privileges();

2539

if(ret_errno != 0){

2540

perror_plus("Failed to raise privileges");

2541

} else {

2542

2543

/* Run network hooks */

2544

run_network_hooks("stop", interfaces_hooks != NULL ?

2545

interfaces_hooks : "", delay);

2546

2547

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

2548

{

2549

char *interface = NULL;

2550

while((interface=argz_next(interfaces_to_take_down,

2551

interfaces_to_take_down_size,

2552

interface))){

2553

ret_errno = take_down_interface(interface);

2554

if(ret_errno != 0){

2555

errno = ret_errno;

2556

perror_plus("Failed to take down interface");

2557

}

2558

}

2559

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

2560

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

2561

" down\n");

2562

}

2563

}

2238

2564

}

2239

2565

2240

/* Take down the network interface */

2241

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

2242

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

2243

if(ret == -1){

2244

perror_plus("ioctl SIOCGIFFLAGS");

2245

} else if(network.ifr_flags & IFF_UP){

2246

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

2247

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

2248

if(ret == -1){

2249

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2250

}

2251

}

2252

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

2253

if(ret == -1){

2254

perror_plus("close");

2255

}

2566

ret_errno = lower_privileges_permanently();

2567

if(ret_errno != 0){

2568

perror_plus("Failed to lower privileges permanently");

2256

2569

}

2257

2570

}

2258

/* Lower privileges permanently */

2259

errno = 0;

2260

ret = setuid(uid);

2261

if(ret == -1){

2262

perror_plus("setuid");

2263

}

2571

2572

free(interfaces_to_take_down);

2573

free(interfaces_hooks);

2264

2574

2265

2575

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

2266

if(tempdir_created){

2576

if(tempdir != NULL){

2267

2577

struct dirent **direntries = NULL;

2268

2578

struct dirent *direntry = NULL;

2269

2579

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

2270

2580

alphasort);

2271

if (numentries > 0){

2581

if(numentries > 0){

2272

2582

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

2273

2583

direntry = direntries[i];

2274

2584

char *fullname = NULL;

2289

2599

2290

2600

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

2291

2601

free(direntries);

2292

if (numentries == -1){

2602

if(numentries == -1){

2293

2603

perror_plus("scandir");

2294

2604

}

2295

2605

ret = rmdir(tempdir);