/mandos/release : revision 237.7.144

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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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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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#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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#ifdef __linux__

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

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115

init_gnutls_session(),

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116

GNUTLS_* */

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117

#include <gnutls/openpgp.h>

111

/* gnutls_certificate_set_openpgp_key_file(),

112

GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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120

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/* GPGME */

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

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130

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

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131

#define SECKEY "seckey.txt"

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132

#define PUBKEY "pubkey.txt"

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

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134

127

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bool debug = false;

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136

static const char mandos_protocol_version[] = "1";

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

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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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144

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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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/* Function to use when printing errors */

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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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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)))

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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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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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}

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173

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/*

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* 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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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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211

}

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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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221

}

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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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perror_plus("strdup");

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return -1;

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return false;

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}

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/* Special case of first server */

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if (mc.current_server == NULL){

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return -1;

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return false;

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}

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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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*/

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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,

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const char *tempdir){

233

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gpgme_error_t rc;

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256

gpgme_engine_info_t engine_info;

235

257

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272

251

273

rc = gpgme_data_new_from_fd(&pgp_data, fd);

252

274

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));

275

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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277

return false;

256

278

}

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279

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rc = gpgme_op_import(mc.ctx, pgp_data);

259

281

if(rc != GPG_ERR_NO_ERROR){

260

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

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gpgme_strsource(rc), gpgme_strerror(rc));

282

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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284

return false;

263

285

}

264

286

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293

}

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273

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if(debug){

274

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

296

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

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297

}

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/* Init GPGME */

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gpgme_check_version(NULL);

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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

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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));

303

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

284

306

}

285

307

286

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

287

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rc = gpgme_get_engine_info(&engine_info);

288

310

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));

311

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

312

gpgme_strsource(rc), gpgme_strerror(rc));

291

313

return false;

292

314

}

293

315

while(engine_info != NULL){

299

321

engine_info = engine_info->next;

300

322

}

301

323

if(engine_info == NULL){

302

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

324

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

325

tempdir);

303

326

return false;

304

327

}

305

328

306

329

/* Create new GPGME "context" */

307

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

308

331

if(rc != GPG_ERR_NO_ERROR){

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

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

334

gpgme_strerror(rc));

311

335

return false;

312

336

}

313

337

332

356

ssize_t plaintext_length = 0;

333

357

334

358

if(debug){

335

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

359

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

336

360

}

337

361

338

362

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

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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

340

364

0);

341

365

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));

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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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368

return -1;

345

369

}

346

370

347

371

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

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rc = gpgme_data_new(&dh_plain);

349

373

if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

374

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

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

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gpgme_strsource(rc), gpgme_strerror(rc));

352

377

gpgme_data_release(dh_crypto);

353

378

return -1;

354

379

}

357

382

data buffer */

358

383

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

359

384

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

385

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

386

gpgme_strsource(rc), gpgme_strerror(rc));

362

387

plaintext_length = -1;

363

388

if(debug){

364

389

gpgme_decrypt_result_t result;

365

390

result = gpgme_op_decrypt_result(mc.ctx);

366

391

if(result == NULL){

367

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

392

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

368

393

} 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);

394

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

395

result->unsupported_algorithm);

396

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

397

result->wrong_key_usage);

373

398

if(result->file_name != NULL){

374

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

399

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

375

400

}

376

401

gpgme_recipient_t recipient;

377

402

recipient = result->recipients;

378

403

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");

404

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

405

gpgme_pubkey_algo_name

406

(recipient->pubkey_algo));

407

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

408

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

409

recipient->status == GPG_ERR_NO_SECKEY

410

? "No" : "Yes");

385

411

recipient = recipient->next;

386

412

}

387

413

}

390

416

}

391

417

392

418

if(debug){

393

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

419

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

394

420

}

395

421

396

422

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

403

429

*plaintext = NULL;

404

430

while(true){

405

431

plaintext_capacity = incbuffer(plaintext,

406

(size_t)plaintext_length,

407

plaintext_capacity);

432

(size_t)plaintext_length,

433

plaintext_capacity);

408

434

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

435

perror_plus("incbuffer");

436

plaintext_length = -1;

437

goto decrypt_end;

412

438

}

413

439

414

440

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

427

453

}

428

454

429

455

if(debug){

430

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

456

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

431

457

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

432

458

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

433

459

}

455

481

/* GnuTLS log function callback */

456

482

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

457

483

const char* string){

458

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

484

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

459

485

}

460

486

461

487

static int init_gnutls_global(const char *pubkeyfilename,

463

489

int ret;

464

490

465

491

if(debug){

466

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

492

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

467

493

}

468

494

469

495

ret = gnutls_global_init();

470

496

if(ret != GNUTLS_E_SUCCESS){

471

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

472

safer_gnutls_strerror(ret));

497

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

498

safer_gnutls_strerror(ret));

473

499

return -1;

474

500

}

475

501

484

510

/* OpenPGP credentials */

485

511

ret = gnutls_certificate_allocate_credentials(&mc.cred);

486

512

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

513

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

514

safer_gnutls_strerror(ret));

489

515

gnutls_global_deinit();

490

516

return -1;

491

517

}

492

518

493

519

if(debug){

494

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

495

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

496

seckeyfilename);

520

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

521

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

522

pubkeyfilename,

523

seckeyfilename);

497

524

}

498

525

499

526

ret = gnutls_certificate_set_openpgp_key_file

500

527

(mc.cred, pubkeyfilename, seckeyfilename,

501

528

GNUTLS_OPENPGP_FMT_BASE64);

502

529

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));

530

fprintf_plus(stderr,

531

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

532

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

533

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

534

safer_gnutls_strerror(ret));

508

535

goto globalfail;

509

536

}

510

537

511

538

/* GnuTLS server initialization */

512

539

ret = gnutls_dh_params_init(&mc.dh_params);

513

540

if(ret != GNUTLS_E_SUCCESS){

514

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

515

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

541

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

542

" initialization: %s\n",

543

safer_gnutls_strerror(ret));

516

544

goto globalfail;

517

545

}

518

546

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

519

547

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

548

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

549

safer_gnutls_strerror(ret));

522

550

goto globalfail;

523

551

}

524

552

544

572

}

545

573

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

546

574

if(ret != GNUTLS_E_SUCCESS){

547

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

548

safer_gnutls_strerror(ret));

575

fprintf_plus(stderr,

576

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

577

safer_gnutls_strerror(ret));

549

578

}

550

579

551

580

{

558

587

}

559

588

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

560

589

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));

590

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

591

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

592

safer_gnutls_strerror(ret));

564

593

gnutls_deinit(*session);

565

594

return -1;

566

595

}

575

604

}

576

605

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

577

606

if(ret != GNUTLS_E_SUCCESS){

578

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

579

safer_gnutls_strerror(ret));

607

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

608

safer_gnutls_strerror(ret));

580

609

gnutls_deinit(*session);

581

610

return -1;

582

611

}

627

656

pf = PF_INET;

628

657

break;

629

658

default:

630

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

659

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

631

660

errno = EINVAL;

632

661

return -1;

633

662

}

638

667

}

639

668

640

669

if(debug){

641

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

642

"\n", ip, port);

670

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

671

PRIu16 "\n", ip, port);

643

672

}

644

673

645

674

tcp_sd = socket(pf, SOCK_STREAM, 0);

671

700

}

672

701

if(ret == 0){

673

702

int e = errno;

674

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

703

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

675

704

errno = e;

676

705

goto mandos_end;

677

706

}

682

711

683

712

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

713

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

685

-Wunreachable-code*/

714

-Wunreachable-code*/

686

715

if(if_index == AVAHI_IF_UNSPEC){

687

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

688

" without a network interface\n");

716

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

717

" incomplete without a network interface\n");

689

718

errno = EINVAL;

690

719

goto mandos_end;

691

720

}

709

738

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

710

739

perror_plus("if_indextoname");

711

740

} else {

712

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

713

ip, interface, port);

741

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

742

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

714

743

}

715

744

} else {

716

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

717

port);

745

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

746

ip, port);

718

747

}

719

748

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

720

749

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

730

759

perror_plus("inet_ntop");

731

760

} else {

732

761

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

733

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

762

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

734

763

}

735

764

}

736

765

}

764

793

while(true){

765

794

size_t out_size = strlen(out);

766

795

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

767

out_size - written));

796

out_size - written));

768

797

if(ret == -1){

769

798

int e = errno;

770

799

perror_plus("write");

790

819

}

791

820

792

821

if(debug){

793

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

822

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

794

823

}

795

824

796

825

if(quit_now){

798

827

goto mandos_end;

799

828

}

800

829

801

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

802

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

830

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

831

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

832

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

833

gnutls_transport_set_ptr(session,

834

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

803

835

804

836

if(quit_now){

805

837

errno = EINTR;

816

848

817

849

if(ret != GNUTLS_E_SUCCESS){

818

850

if(debug){

819

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

851

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

820

852

gnutls_perror(ret);

821

853

}

822

854

errno = EPROTO;

826

858

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

827

859

828

860

if(debug){

829

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

830

ip);

861

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

862

" %s\n", ip);

831

863

}

832

864

833

865

while(true){

838

870

}

839

871

840

872

buffer_capacity = incbuffer(&buffer, buffer_length,

841

buffer_capacity);

873

buffer_capacity);

842

874

if(buffer_capacity == 0){

843

875

int e = errno;

844

876

perror_plus("incbuffer");

871

903

}

872

904

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

873

905

if(ret < 0){

874

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

906

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

907

"***\n");

875

908

gnutls_perror(ret);

876

909

errno = EPROTO;

877

910

goto mandos_end;

878

911

}

879

912

break;

880

913

default:

881

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

882

" encrypted session with Mandos server\n");

914

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

915

" encrypted session with Mandos server\n");

883

916

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

917

errno = EIO;

885

918

goto mandos_end;

890

923

}

891

924

892

925

if(debug){

893

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

926

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

894

927

}

895

928

896

929

if(quit_now){

908

941

909

942

if(buffer_length > 0){

910

943

ssize_t decrypted_buffer_size;

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

944

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

913

945

&decrypted_buffer);

914

946

if(decrypted_buffer_size >= 0){

915

947

926

958

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

927

959

int e = errno;

928

960

if(debug){

929

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

930

strerror(errno));

961

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

962

strerror(errno));

931

963

}

932

964

errno = e;

933

965

goto mandos_end;

990

1022

switch(event){

991

1023

default:

992

1024

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)));

1025

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

1026

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

1027

domain,

1028

avahi_strerror(avahi_server_errno(mc.server)));

996

1029

break;

997

1030

998

1031

case AVAHI_RESOLVER_FOUND:

1000

1033

char ip[AVAHI_ADDRESS_STR_MAX];

1001

1034

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

1002

1035

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);

1036

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

1037

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

1038

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

1006

1039

}

1007

1040

int ret = start_mandos_communication(ip, port, interface,

1008

1041

avahi_proto_to_af(proto));

1009

1042

if(ret == 0){

1010

1043

avahi_simple_poll_quit(mc.simple_poll);

1011

1044

} else {

1012

ret = add_server(ip, port, interface,

1013

avahi_proto_to_af(proto));

1045

if(not add_server(ip, port, interface,

1046

avahi_proto_to_af(proto))){

1047

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

1048

" list\n", name);

1049

}

1014

1050

}

1015

1051

}

1016

1052

}

1040

1076

default:

1041

1077

case AVAHI_BROWSER_FAILURE:

1042

1078

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1079

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

1080

avahi_strerror(avahi_server_errno(mc.server)));

1045

1081

avahi_simple_poll_quit(mc.simple_poll);

1046

1082

return;

1047

1083

1054

1090

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

1055

1091

name, type, domain, protocol, 0,

1056

1092

resolve_callback, NULL) == NULL)

1057

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

1058

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

1093

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

1094

" %s\n", name,

1095

avahi_strerror(avahi_server_errno(mc.server)));

1059

1096

break;

1060

1097

1061

1098

case AVAHI_BROWSER_REMOVE:

1064

1101

case AVAHI_BROWSER_ALL_FOR_NOW:

1065

1102

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1066

1103

if(debug){

1067

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

1104

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

1105

" searching...\n");

1068

1106

}

1069

1107

break;

1070

1108

}

1087

1125

1088

1126

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

1089

1127

int ret;

1128

error_t ret_errno;

1090

1129

1091

1130

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

1092

1131

if(s < 0){

1132

ret_errno = errno;

1093

1133

perror_plus("socket");

1134

errno = ret_errno;

1094

1135

return false;

1095

1136

}

1096

1137

strcpy(ifr->ifr_name, ifname);

1097

1138

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1098

1139

if(ret == -1){

1099

1140

if(debug){

1141

ret_errno = errno;

1100

1142

perror_plus("ioctl SIOCGIFFLAGS");

1143

errno = ret_errno;

1101

1144

}

1102

1145

return false;

1103

1146

}

1109

1152

/* Reject the loopback device */

1110

1153

if(ifr->ifr_flags & IFF_LOOPBACK){

1111

1154

if(debug){

1112

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

1113

ifname);

1155

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

1156

ifname);

1114

1157

}

1115

1158

return false;

1116

1159

}

1117

1160

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

1118

1161

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

1119

1162

if(debug){

1120

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

1121

ifname);

1163

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

1164

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

1122

1165

}

1123

1166

return true;

1124

1167

}

1125

1168

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

1126

1169

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

1127

1170

if(debug){

1128

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

1129

ifname);

1171

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1172

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

1130

1173

}

1131

1174

return false;

1132

1175

}

1133

1176

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

1134

1177

if(ifr->ifr_flags & IFF_NOARP){

1135

1178

if(debug){

1136

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

1179

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

1180

ifname);

1137

1181

}

1138

1182

return false;

1139

1183

}

1140

1184

1141

1185

/* Accept this device */

1142

1186

if(debug){

1143

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

1187

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

1144

1188

}

1145

1189

return true;

1146

1190

}

1151

1195

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

1152

1196

*/

1153

1197

int good_interface(const struct dirent *if_entry){

1154

int ret;

1155

1198

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

1156

1199

return 0;

1157

1200

}

1201

1158

1202

struct ifreq ifr;

1159

1160

1203

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

1204

if(debug){

1205

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

1206

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

1207

}

1161

1208

return 0;

1162

1209

}

1163

1210

1167

1214

return 1;

1168

1215

}

1169

1216

1217

/*

1218

* This function determines if a network interface is up.

1219

*/

1220

bool interface_is_up(const char *interface){

1221

struct ifreq ifr;

1222

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

1223

if(debug){

1224

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

1225

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

1226

}

1227

return false;

1228

}

1229

1230

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

1231

}

1232

1233

/*

1234

* This function determines if a network interface is running

1235

*/

1236

bool interface_is_running(const char *interface){

1237

struct ifreq ifr;

1238

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

1239

if(debug){

1240

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

1241

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

1242

}

1243

return false;

1244

}

1245

1246

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

1247

}

1248

1170

1249

int notdotentries(const struct dirent *direntry){

1171

1250

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

1172

1251

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

1178

1257

return 1;

1179

1258

}

1180

1259

1260

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

1261

int runnable_hook(const struct dirent *direntry){

1262

int ret;

1263

size_t sret;

1264

struct stat st;

1265

1266

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

1267

/* Empty name? */

1268

return 0;

1269

}

1270

1271

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

1272

"abcdefghijklmnopqrstuvwxyz"

1273

"0123456789"

1274

"_-");

1275

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

1276

/* Contains non-allowed characters */

1277

if(debug){

1278

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

1279

direntry->d_name);

1280

}

1281

return 0;

1282

}

1283

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1292

if(ret == -1){

1293

if(debug){

1294

perror_plus("Could not stat hook");

1295

}

1296

return 0;

1297

}

1298

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

1299

/* Not a regular file */

1300

if(debug){

1301

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

1302

direntry->d_name);

1303

}

1304

return 0;

1305

}

1306

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

1307

/* Not executable */

1308

if(debug){

1309

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

1310

direntry->d_name);

1311

}

1312

return 0;

1313

}

1314

if(debug){

1315

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

1316

direntry->d_name);

1317

}

1318

return 1;

1319

}

1320

1181

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1182

1322

int ret;

1183

1323

struct timespec now;

1187

1327

while(true){

1188

1328

if(mc.current_server == NULL){

1189

1329

if (debug){

1190

fprintf(stderr,

1191

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

1330

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

1331

" No timeout!\n");

1192

1332

}

1193

1333

ret = avahi_simple_poll_iterate(s, -1);

1194

1334

} else {

1195

1335

if (debug){

1196

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

1197

" or wait\n");

1336

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

1337

" it, or wait\n");

1198

1338

}

1199

1339

/* the current time */

1200

1340

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1216

1356

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

1217

1357

1218

1358

if (debug){

1219

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

1359

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

1360

block_time);

1220

1361

}

1221

1362

1222

1363

if(block_time <= 0){

1242

1383

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

1243

1384

}

1244

1385

if(ret != 0){

1245

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

1386

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

1246

1387

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

1247

1388

}

1248

1389

}

1249

1390

}

1250

1391

}

1251

1392

1393

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

1394

error_t raise_privileges(void){

1395

error_t old_errno = errno;

1396

error_t ret_errno = 0;

1397

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

1398

ret_errno = errno;

1399

perror_plus("seteuid");

1400

}

1401

errno = old_errno;

1402

return ret_errno;

1403

}

1404

1405

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

1406

error_t raise_privileges_permanently(void){

1407

error_t old_errno = errno;

1408

error_t ret_errno = raise_privileges();

1409

if(ret_errno != 0){

1410

errno = old_errno;

1411

return ret_errno;

1412

}

1413

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

1414

ret_errno = errno;

1415

perror_plus("seteuid");

1416

}

1417

errno = old_errno;

1418

return ret_errno;

1419

}

1420

1421

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

1422

error_t lower_privileges(void){

1423

error_t old_errno = errno;

1424

error_t ret_errno = 0;

1425

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

1426

ret_errno = errno;

1427

perror_plus("seteuid");

1428

}

1429

errno = old_errno;

1430

return ret_errno;

1431

}

1432

1433

/* Lower privileges permanently */

1434

error_t lower_privileges_permanently(void){

1435

error_t old_errno = errno;

1436

error_t ret_errno = 0;

1437

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

1438

ret_errno = errno;

1439

perror_plus("setuid");

1440

}

1441

errno = old_errno;

1442

return ret_errno;

1443

}

1444

1445

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

1446

const float delay){

1447

struct dirent **direntries;

1448

struct dirent *direntry;

1449

int ret;

1450

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

1451

alphasort);

1452

if(numhooks == -1){

1453

perror_plus("scandir");

1454

} else {

1455

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

1456

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

1457

direntry = direntries[i];

1458

char *fullname = NULL;

1459

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

1460

if(ret < 0){

1461

perror_plus("asprintf");

1462

continue;

1463

}

1464

if(debug){

1465

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

1466

direntry->d_name);

1467

}

1468

pid_t hook_pid = fork();

1469

if(hook_pid == 0){

1470

/* Child */

1471

/* Raise privileges */

1472

raise_privileges_permanently();

1473

/* Set group */

1474

errno = 0;

1475

ret = setgid(0);

1476

if(ret == -1){

1477

perror_plus("setgid");

1478

}

1479

/* Reset supplementary groups */

1480

errno = 0;

1481

ret = setgroups(0, NULL);

1482

if(ret == -1){

1483

perror_plus("setgroups");

1484

}

1485

dup2(devnull, STDIN_FILENO);

1486

close(devnull);

1487

dup2(STDERR_FILENO, STDOUT_FILENO);

1488

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

1489

if(ret == -1){

1490

perror_plus("setenv");

1491

_exit(EX_OSERR);

1492

}

1493

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

1494

if(ret == -1){

1495

perror_plus("setenv");

1496

_exit(EX_OSERR);

1497

}

1498

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

1499

if(ret == -1){

1500

perror_plus("setenv");

1501

_exit(EX_OSERR);

1502

}

1503

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

1504

if(ret == -1){

1505

perror_plus("setenv");

1506

_exit(EX_OSERR);

1507

}

1508

char *delaystring;

1509

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

1510

if(ret == -1){

1511

perror_plus("asprintf");

1512

_exit(EX_OSERR);

1513

}

1514

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

1515

if(ret == -1){

1516

free(delaystring);

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

free(delaystring);

1521

if(connect_to != NULL){

1522

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

1523

if(ret == -1){

1524

perror_plus("setenv");

1525

_exit(EX_OSERR);

1526

}

1527

}

1528

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

1529

perror_plus("execl");

1530

_exit(EXIT_FAILURE);

1531

}

1532

} else {

1533

int status;

1534

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

1535

perror_plus("waitpid");

1536

free(fullname);

1537

continue;

1538

}

1539

if(WIFEXITED(status)){

1540

if(WEXITSTATUS(status) != 0){

1541

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

1542

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

1543

WEXITSTATUS(status));

1544

free(fullname);

1545

continue;

1546

}

1547

} else if(WIFSIGNALED(status)){

1548

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

1549

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

1550

WTERMSIG(status));

1551

free(fullname);

1552

continue;

1553

} else {

1554

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

1555

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

1556

free(fullname);

1557

continue;

1558

}

1559

}

1560

free(fullname);

1561

if(debug){

1562

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

1563

direntry->d_name);

1564

}

1565

}

1566

close(devnull);

1567

}

1568

return true;

1569

}

1570

1571

error_t bring_up_interface(const char *const interface,

1572

const float delay){

1573

int sd = -1;

1574

error_t old_errno = errno;

1575

error_t ret_errno = 0;

1576

int ret, ret_setflags;

1577

struct ifreq network;

1578

unsigned int if_index = if_nametoindex(interface);

1579

if(if_index == 0){

1580

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

1581

errno = old_errno;

1582

return ENXIO;

1583

}

1584

1585

if(quit_now){

1586

errno = old_errno;

1587

return EINTR;

1588

}

1589

1590

if(not interface_is_up(interface)){

1591

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

1592

ret_errno = errno;

1593

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

1594

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

1595

return ret_errno;

1596

}

1597

network.ifr_flags |= IFF_UP;

1598

1599

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1600

if(sd < 0){

1601

ret_errno = errno;

1602

perror_plus("socket");

1603

errno = old_errno;

1604

return ret_errno;

1605

}

1606

1607

if(quit_now){

1608

close(sd);

1609

errno = old_errno;

1610

return EINTR;

1611

}

1612

1613

if(debug){

1614

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

1615

interface);

1616

}

1617

1618

/* Raise priviliges */

1619

raise_privileges();

1620

1621

#ifdef __linux__

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

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

1625

bool restore_loglevel = true;

1626

if(ret_linux == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1629

}

1630

#endif /* __linux__ */

1631

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

1632

ret_errno = errno;

1633

#ifdef __linux__

1634

if(restore_loglevel){

1635

ret_linux = klogctl(7, NULL, 0);

1636

if(ret_linux == -1){

1637

perror_plus("klogctl");

1638

}

1639

}

1640

#endif /* __linux__ */

1641

1642

/* Lower privileges */

1643

lower_privileges();

1644

1645

/* Close the socket */

1646

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

1647

if(ret == -1){

1648

perror_plus("close");

1649

}

1650

1651

if(ret_setflags == -1){

1652

errno = ret_errno;

1653

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1654

errno = old_errno;

1655

return ret_errno;

1656

}

1657

} else if(debug){

1658

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

1659

interface);

1660

}

1661

1662

/* Sleep checking until interface is running.

1663

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

1664

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

1665

if(interface_is_running(interface)){

1666

break;

1667

}

1668

struct timespec sleeptime = { .tv_nsec = 250000000 };

1669

ret = nanosleep(&sleeptime, NULL);

1670

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

1671

perror_plus("nanosleep");

1672

}

1673

}

1674

1675

errno = old_errno;

1676

return 0;

1677

}

1678

1679

error_t take_down_interface(const char *const interface){

1680

int sd = -1;

1681

error_t old_errno = errno;

1682

error_t ret_errno = 0;

1683

int ret, ret_setflags;

1684

struct ifreq network;

1685

unsigned int if_index = if_nametoindex(interface);

1686

if(if_index == 0){

1687

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

1688

errno = old_errno;

1689

return ENXIO;

1690

}

1691

if(interface_is_up(interface)){

1692

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

1693

ret_errno = errno;

1694

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

1695

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

1696

return ret_errno;

1697

}

1698

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

1699

1700

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1701

if(sd < 0){

1702

ret_errno = errno;

1703

perror_plus("socket");

1704

errno = old_errno;

1705

return ret_errno;

1706

}

1707

1708

if(debug){

1709

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

1710

interface);

1711

}

1712

1713

/* Raise priviliges */

1714

raise_privileges();

1715

1716

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

1717

ret_errno = errno;

1718

1719

/* Lower privileges */

1720

lower_privileges();

1721

1722

/* Close the socket */

1723

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

1724

if(ret == -1){

1725

perror_plus("close");

1726

}

1727

1728

if(ret_setflags == -1){

1729

errno = ret_errno;

1730

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1731

errno = old_errno;

1732

return ret_errno;

1733

}

1734

} else if(debug){

1735

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

1736

interface);

1737

}

1738

1739

errno = old_errno;

1740

return 0;

1741

}

1742

1252

1743

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

1253

1744

AvahiSServiceBrowser *sb = NULL;

1254

int error;

1745

error_t ret_errno;

1255

1746

int ret;

1256

1747

intmax_t tmpmax;

1257

1748

char *tmp;

1258

1749

int exitcode = EXIT_SUCCESS;

1259

const char *interface = "";

1260

struct ifreq network;

1261

int sd = -1;

1262

bool take_down_interface = false;

1263

uid_t uid;

1264

gid_t gid;

1750

char *interfaces = NULL;

1751

size_t interfaces_size = 0;

1752

char *interfaces_to_take_down = NULL;

1753

size_t interfaces_to_take_down_size = 0;

1265

1754

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

1266

1755

bool tempdir_created = false;

1267

1756

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1268

1757

const char *seckey = PATHDIR "/" SECKEY;

1269

1758

const char *pubkey = PATHDIR "/" PUBKEY;

1759

char *interfaces_hooks = NULL;

1760

size_t interfaces_hooks_size = 0;

1270

1761

1271

1762

bool gnutls_initialized = false;

1272

1763

bool gpgme_initialized = false;

1334

1825

.group = 2 },

1335

1826

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

1336

1827

.arg = "SECONDS",

1337

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

1828

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

1829

.group = 2 },

1830

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

1831

.arg = "DIR",

1832

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

1338

1833

.group = 2 },

1339

1834

/*

1340

1835

* These reproduce what we would get without ARGP_NO_HELP

1359

1854

connect_to = arg;

1360

1855

break;

1361

1856

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

1362

interface = arg;

1857

ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,

1858

(int)',');

1859

if(ret_errno != 0){

1860

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

1861

}

1363

1862

break;

1364

1863

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

1365

1864

seckey = arg;

1394

1893

argp_error(state, "Bad retry interval");

1395

1894

}

1396

1895

break;

1896

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

1897

hookdir = arg;

1898

break;

1397

1899

/*

1398

1900

* These reproduce what we would get without ARGP_NO_HELP

1399

1901

*/

1405

1907

argp_state_help(state, state->out_stream,

1406

1908

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1407

1909

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

1408

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

1910

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

1409

1911

exit(argp_err_exit_status);

1410

1912

break;

1411

1913

default:

1438

1940

{

1439

1941

/* Work around Debian bug #633582:

1440

1942

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

1441

struct stat st;

1442

1943

1443

1944

/* Re-raise priviliges */

1444

errno = 0;

1445

ret = seteuid(0);

1446

if(ret == -1){

1447

perror_plus("seteuid");

1448

}

1449

1450

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

1451

int seckey_fd = open(seckey, O_RDONLY);

1452

if(seckey_fd == -1){

1453

perror_plus("open");

1454

} else {

1455

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

1456

if(ret == -1){

1457

perror_plus("fstat");

1458

} else {

1459

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

1460

ret = fchown(seckey_fd, uid, gid);

1461

if(ret == -1){

1462

perror_plus("fchown");

1463

}

1464

}

1465

}

1466

TEMP_FAILURE_RETRY(close(seckey_fd));

1467

}

1468

}

1469

1470

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

1471

int pubkey_fd = open(pubkey, O_RDONLY);

1472

if(pubkey_fd == -1){

1473

perror_plus("open");

1474

} else {

1475

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

1476

if(ret == -1){

1477

perror_plus("fstat");

1478

} else {

1479

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

1480

ret = fchown(pubkey_fd, uid, gid);

1481

if(ret == -1){

1482

perror_plus("fchown");

1483

}

1484

}

1485

}

1486

TEMP_FAILURE_RETRY(close(pubkey_fd));

1487

}

1488

}

1489

1490

/* Lower privileges */

1491

errno = 0;

1492

ret = seteuid(uid);

1493

if(ret == -1){

1494

perror_plus("seteuid");

1945

if(raise_privileges() == 0){

1946

struct stat st;

1947

1948

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

1949

int seckey_fd = open(seckey, O_RDONLY);

1950

if(seckey_fd == -1){

1951

perror_plus("open");

1952

} else {

1953

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

1954

if(ret == -1){

1955

perror_plus("fstat");

1956

} else {

1957

if(S_ISREG(st.st_mode)

1958

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

1959

ret = fchown(seckey_fd, uid, gid);

1960

if(ret == -1){

1961

perror_plus("fchown");

1962

}

1963

}

1964

}

1965

TEMP_FAILURE_RETRY(close(seckey_fd));

1966

}

1967

}

1968

1969

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

1970

int pubkey_fd = open(pubkey, O_RDONLY);

1971

if(pubkey_fd == -1){

1972

perror_plus("open");

1973

} else {

1974

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

1975

if(ret == -1){

1976

perror_plus("fstat");

1977

} else {

1978

if(S_ISREG(st.st_mode)

1979

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

1980

ret = fchown(pubkey_fd, uid, gid);

1981

if(ret == -1){

1982

perror_plus("fchown");

1983

}

1984

}

1985

}

1986

TEMP_FAILURE_RETRY(close(pubkey_fd));

1987

}

1988

}

1989

1990

/* Lower privileges */

1991

errno = 0;

1992

ret = seteuid(uid);

1993

if(ret == -1){

1994

perror_plus("seteuid");

1995

}

1996

}

1997

}

1998

1999

/* Remove empty interface names */

2000

{

2001

char *interface = NULL;

2002

while((interface = argz_next(interfaces, interfaces_size,

2003

interface))){

2004

if(if_nametoindex(interface) == 0){

2005

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

2006

fprintf_plus(stderr, "Not using nonexisting interface"

2007

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

2008

}

2009

argz_delete(&interfaces, &interfaces_size, interface);

2010

interface = NULL;

2011

}

2012

}

2013

}

2014

2015

/* Run network hooks */

2016

{

2017

ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,

2018

interfaces, interfaces_size);

2019

if(ret_errno != 0){

2020

errno = ret_errno;

2021

perror_plus("argz_append");

2022

goto end;

2023

}

2024

argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');

2025

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

2026

goto end;

1495

2027

}

1496

2028

}

1497

2029

1498

2030

if(not debug){

1499

2031

avahi_set_log_function(empty_log);

1500

2032

}

1501

1502

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

1503

struct dirent **direntries;

1504

ret = scandir(sys_class_net, &direntries, good_interface,

1505

alphasort);

1506

if(ret >= 1){

1507

/* Pick the first good interface */

1508

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

1509

if(debug){

1510

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

1511

}

1512

if(interface == NULL){

1513

perror_plus("malloc");

1514

free(direntries);

1515

exitcode = EXIT_FAILURE;

1516

goto end;

1517

}

1518

free(direntries);

1519

} else {

1520

free(direntries);

1521

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

1522

exitcode = EXIT_FAILURE;

1523

goto end;

1524

}

1525

}

1526

2033

1527

2034

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

1528

2035

from the signal handler */

1530

2037

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

1531

2038

mc.simple_poll = avahi_simple_poll_new();

1532

2039

if(mc.simple_poll == NULL){

1533

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

2040

fprintf_plus(stderr,

2041

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

1534

2042

exitcode = EX_UNAVAILABLE;

1535

2043

goto end;

1536

2044

}

1598

2106

}

1599

2107

}

1600

2108

1601

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

1602

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

1603

if_index = (AvahiIfIndex) if_nametoindex(interface);

1604

if(if_index == 0){

1605

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

1606

exitcode = EX_UNAVAILABLE;

1607

goto end;

1608

}

1609

1610

if(quit_now){

1611

goto end;

1612

}

1613

1614

/* Re-raise priviliges */

1615

errno = 0;

1616

ret = seteuid(0);

1617

if(ret == -1){

1618

perror_plus("seteuid");

1619

}

1620

1621

#ifdef __linux__

1622

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1623

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

1624

ret = klogctl(8, NULL, 5);

1625

bool restore_loglevel = true;

1626

if(ret == -1){

1627

restore_loglevel = false;

1628

perror_plus("klogctl");

1629

}

1630

#endif /* __linux__ */

1631

1632

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1633

if(sd < 0){

1634

perror_plus("socket");

1635

exitcode = EX_OSERR;

1636

#ifdef __linux__

1637

if(restore_loglevel){

1638

ret = klogctl(7, NULL, 0);

1639

if(ret == -1){

1640

perror_plus("klogctl");

1641

}

1642

}

1643

#endif /* __linux__ */

1644

/* Lower privileges */

1645

errno = 0;

1646

ret = seteuid(uid);

1647

if(ret == -1){

1648

perror_plus("seteuid");

1649

}

1650

goto end;

1651

}

1652

strcpy(network.ifr_name, interface);

1653

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

1654

if(ret == -1){

1655

perror_plus("ioctl SIOCGIFFLAGS");

1656

#ifdef __linux__

1657

if(restore_loglevel){

1658

ret = klogctl(7, NULL, 0);

1659

if(ret == -1){

1660

perror_plus("klogctl");

1661

}

1662

}

1663

#endif /* __linux__ */

1664

exitcode = EX_OSERR;

1665

/* Lower privileges */

1666

errno = 0;

1667

ret = seteuid(uid);

1668

if(ret == -1){

1669

perror_plus("seteuid");

1670

}

1671

goto end;

1672

}

1673

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

1674

network.ifr_flags |= IFF_UP;

1675

take_down_interface = true;

1676

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

1677

if(ret == -1){

1678

take_down_interface = false;

1679

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1680

exitcode = EX_OSERR;

1681

#ifdef __linux__

1682

if(restore_loglevel){

1683

ret = klogctl(7, NULL, 0);

1684

if(ret == -1){

1685

perror_plus("klogctl");

1686

}

1687

}

1688

#endif /* __linux__ */

1689

/* Lower privileges */

1690

errno = 0;

1691

ret = seteuid(uid);

1692

if(ret == -1){

1693

perror_plus("seteuid");

1694

}

1695

goto end;

1696

}

1697

}

1698

/* Sleep checking until interface is running.

1699

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

1700

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

1701

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

1702

if(ret == -1){

1703

perror_plus("ioctl SIOCGIFFLAGS");

1704

} else if(network.ifr_flags & IFF_RUNNING){

1705

break;

1706

}

1707

struct timespec sleeptime = { .tv_nsec = 250000000 };

1708

ret = nanosleep(&sleeptime, NULL);

1709

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

1710

perror_plus("nanosleep");

1711

}

1712

}

1713

if(not take_down_interface){

1714

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

1715

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

1716

if(ret == -1){

1717

perror_plus("close");

1718

}

1719

}

1720

#ifdef __linux__

1721

if(restore_loglevel){

1722

/* Restores kernel loglevel to default */

1723

ret = klogctl(7, NULL, 0);

1724

if(ret == -1){

1725

perror_plus("klogctl");

1726

}

1727

}

1728

#endif /* __linux__ */

1729

/* Lower privileges */

1730

errno = 0;

1731

if(take_down_interface){

1732

/* Lower privileges */

1733

ret = seteuid(uid);

1734

if(ret == -1){

1735

perror_plus("seteuid");

1736

}

2109

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

2110

if(interfaces == NULL){

2111

struct dirent **direntries;

2112

/* Look for any good interfaces */

2113

ret = scandir(sys_class_net, &direntries, good_interface,

2114

alphasort);

2115

if(ret >= 1){

2116

/* Add all found interfaces to interfaces list */

2117

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

2118

ret_errno = argz_add(&interfaces, &interfaces_size,

2119

direntries[i]->d_name);

2120

if(ret_errno != 0){

2121

perror_plus("argz_add");

2122

continue;

2123

}

2124

if(debug){

2125

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

2126

direntries[i]->d_name);

2127

}

2128

}

2129

free(direntries);

1737

2130

} else {

1738

/* Lower privileges permanently */

1739

ret = setuid(uid);

1740

if(ret == -1){

1741

perror_plus("setuid");

2131

free(direntries);

2132

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

2133

exitcode = EXIT_FAILURE;

2134

goto end;

2135

}

2136

}

2137

2138

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

2139

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

2140

if(debug){

2141

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

2142

interfaces);

2143

}

2144

if_index = (AvahiIfIndex)if_nametoindex(interfaces);

2145

}

2146

2147

/* Bring up interfaces which are down */

2148

if(not (argz_count(interfaces, interfaces_size) == 1

2149

and strcmp(interfaces, "none") == 0)){

2150

char *interface = NULL;

2151

while((interface = argz_next(interfaces, interfaces_size,

2152

interface))){

2153

bool interface_was_up = interface_is_up(interface);

2154

ret = bring_up_interface(interface, delay);

2155

if(not interface_was_up){

2156

if(ret != 0){

2157

errno = ret;

2158

perror_plus("Failed to bring up interface");

2159

} else {

2160

ret_errno = argz_add(&interfaces_to_take_down,

2161

&interfaces_to_take_down_size,

2162

interface);

2163

}

1742

2164

}

1743

2165

}

2166

free(interfaces);

2167

interfaces = NULL;

2168

interfaces_size = 0;

2169

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

2170

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

2171

}

1744

2172

}

1745

2173

1746

2174

if(quit_now){

1749

2177

1750

2178

ret = init_gnutls_global(pubkey, seckey);

1751

2179

if(ret == -1){

1752

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

2180

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

1753

2181

exitcode = EX_UNAVAILABLE;

1754

2182

goto end;

1755

2183

} else {

1771

2199

}

1772

2200

1773

2201

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

1774

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

2202

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

1775

2203

exitcode = EX_UNAVAILABLE;

1776

2204

goto end;

1777

2205

} else {

1786

2214

/* Connect directly, do not use Zeroconf */

1787

2215

/* (Mainly meant for debugging) */

1788

2216

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

2217

1789

2218

if(address == NULL){

1790

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

2219

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

1791

2220

exitcode = EX_USAGE;

1792

2221

goto end;

1793

2222

}

1801

2230

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

1802

2231

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

1803

2232

or tmpmax != (uint16_t)tmpmax){

1804

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

2233

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

1805

2234

exitcode = EX_USAGE;

1806

2235

goto end;

1807

2236

}

1837

2266

break;

1838

2267

}

1839

2268

if(debug){

1840

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

1841

(int)retry_interval);

2269

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

2270

(int)retry_interval);

1842

2271

}

1843

2272

sleep((int)retry_interval);

1844

2273

}

1846

2275

if (not quit_now){

1847

2276

exitcode = EXIT_SUCCESS;

1848

2277

}

1849

2278

1850

2279

goto end;

1851

2280

}

1852

2281

1866

2295

/* Allocate a new server */

1867

2296

mc.server = avahi_server_new(avahi_simple_poll_get

1868

2297

(mc.simple_poll), &config, NULL,

1869

NULL, &error);

2298

NULL, &ret_errno);

1870

2299

1871

2300

/* Free the Avahi configuration data */

1872

2301

avahi_server_config_free(&config);

1874

2303

1875

2304

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

1876

2305

if(mc.server == NULL){

1877

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

1878

avahi_strerror(error));

2306

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

2307

avahi_strerror(ret_errno));

1879

2308

exitcode = EX_UNAVAILABLE;

1880

2309

goto end;

1881

2310

}

1889

2318

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1890

2319

NULL, 0, browse_callback, NULL);

1891

2320

if(sb == NULL){

1892

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

1893

avahi_strerror(avahi_server_errno(mc.server)));

2321

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

2322

avahi_strerror(avahi_server_errno(mc.server)));

1894

2323

exitcode = EX_UNAVAILABLE;

1895

2324

goto end;

1896

2325

}

1902

2331

/* Run the main loop */

1903

2332

1904

2333

if(debug){

1905

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

2334

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

1906

2335

}

1907

2336

1908

2337

ret = avahi_loop_with_timeout(mc.simple_poll,

1909

2338

(int)(retry_interval * 1000));

1910

2339

if(debug){

1911

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

1912

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

2340

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

2341

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

1913

2342

}

1914

2343

1915

2344

end:

1916

2345

1917

2346

if(debug){

1918

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

2347

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

1919

2348

}

1920

2349

1921

2350

/* Cleanup things */

1937

2366

if(gpgme_initialized){

1938

2367

gpgme_release(mc.ctx);

1939

2368

}

1940

2369

1941

2370

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

1942

2371

has seen */

1943

2372

if(mc.current_server != NULL){

1949

2378

}

1950

2379

}

1951

2380

1952

/* Take down the network interface */

1953

if(take_down_interface){

1954

/* Re-raise priviliges */

1955

errno = 0;

1956

ret = seteuid(0);

1957

if(ret == -1){

1958

perror_plus("seteuid");

1959

}

1960

if(geteuid() == 0){

1961

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

1962

if(ret == -1){

1963

perror_plus("ioctl SIOCGIFFLAGS");

1964

} else if(network.ifr_flags & IFF_UP) {

1965

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

1966

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

1967

if(ret == -1){

1968

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2381

/* Re-raise priviliges */

2382

{

2383

raise_privileges();

2384

2385

/* Run network hooks */

2386

run_network_hooks("stop", interfaces_hooks, delay);

2387

2388

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

2389

{

2390

char *interface = NULL;

2391

while((interface=argz_next(interfaces_to_take_down,

2392

interfaces_to_take_down_size,

2393

interface))){

2394

ret_errno = take_down_interface(interface);

2395

if(ret_errno != 0){

2396

errno = ret_errno;

2397

perror_plus("Failed to take down interface");

1969

2398

}

1970

2399

}

1971

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

1972

if(ret == -1){

1973

perror_plus("close");

1974

}

1975

/* Lower privileges permanently */

1976

errno = 0;

1977

ret = setuid(uid);

1978

if(ret == -1){

1979

perror_plus("setuid");

2400

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

2401

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

2402

" down\n");

1980

2403

}

1981

2404

}

2405

2406

lower_privileges_permanently();

1982

2407

}

1983

2408

2409

free(interfaces_to_take_down);

2410

free(interfaces_hooks);

2411

1984

2412

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

1985

2413

if(tempdir_created){

1986

2414

struct dirent **direntries = NULL;

1999

2427

}

2000

2428

ret = remove(fullname);

2001

2429

if(ret == -1){

2002

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

2003

strerror(errno));

2430

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

2431

strerror(errno));

2004

2432

}

2005

2433

free(fullname);

2006

2434

}