/mandos/release : revision 237.16.1

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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

32

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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61

*/

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

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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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*/

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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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unlinkat() */

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

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setgid(), pause() */

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

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

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

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argp_state, struct argp,

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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90

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

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init_gnutls_session(),

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109

GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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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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/* GPGME */

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

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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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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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137

const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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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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149

AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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151

unsigned int dh_bits;

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153

const char *priority;

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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 so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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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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163

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sig_atomic_t quit_now = 0;

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165

int signal_received = 0;

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/* Function to use when printing errors */

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168

void perror_plus(const char *print_text){

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int e = errno;

182

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

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170

program_invocation_short_name);

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errno = e;

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171

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;

191

va_start (ap, format);

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

194

program_invocation_short_name));

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

196

}

197

198

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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,

201

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* "buffer_length" is how much is already used.

202

178

*/

203

__attribute__((nonnull, warn_unused_result))

204

179

size_t incbuffer(char **buffer, size_t buffer_length,

205

size_t buffer_capacity){

180

size_t buffer_capacity){

206

181

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

182

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

183

if(buffer == NULL){

213

184

return 0;

214

185

}

215

*buffer = new_buf;

216

186

buffer_capacity += BUFFER_SIZE;

217

187

}

218

188

return buffer_capacity;

219

189

}

220

190

221

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

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

192

int add_server(const char *ip, uint16_t port,

193

AvahiIfIndex if_index,

194

int af){

225

195

int ret;

226

196

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

227

197

if(new_server == NULL){

228

198

perror_plus("malloc");

229

return false;

199

return -1;

230

200

}

231

201

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

232

.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 };

235

205

if(new_server->ip == NULL){

236

206

perror_plus("strdup");

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free(new_server);

238

return false;

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}

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

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#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

207

return -1;

253

208

}

254

209

/* Special case of first server */

255

if(*current_server == NULL){

210

if (mc.current_server == NULL){

256

211

new_server->next = new_server;

257

212

new_server->prev = new_server;

258

*current_server = new_server;

213

mc.current_server = new_server;

214

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

259

215

} else {

260

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

261

new_server->next = *current_server;

262

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

216

new_server->next = mc.current_server;

217

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

263

218

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

219

mc.current_server->prev = new_server;

220

}

221

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

222

if(ret == -1){

223

perror_plus("clock_gettime");

224

return -1;

225

}

226

return 0;

267

227

}

268

228

269

229

/*

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230

* Initialize GPGME.

271

231

*/

272

__attribute__((nonnull, warn_unused_result))

273

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){

232

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

277

234

gpgme_error_t rc;

278

235

gpgme_engine_info_t engine_info;

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236

237

280

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/*

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

282

240

*/

283

bool import_key(const char * const filename){

241

bool import_key(const char *filename){

284

242

int ret;

285

243

int fd;

286

244

gpgme_data_t pgp_data;

293

251

294

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

253

if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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256

return false;

299

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}

300

258

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

259

rc = gpgme_op_import(mc.ctx, pgp_data);

302

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if(rc != GPG_ERR_NO_ERROR){

303

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

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gpgme_strsource(rc), gpgme_strerror(rc));

261

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

262

gpgme_strsource(rc), gpgme_strerror(rc));

305

263

return false;

306

264

}

307

265

314

272

}

315

273

316

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if(debug){

317

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

275

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

318

276

}

319

277

320

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/* Init GPGME */

321

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gpgme_check_version(NULL);

322

280

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

323

281

if(rc != GPG_ERR_NO_ERROR){

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

282

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

283

gpgme_strsource(rc), gpgme_strerror(rc));

326

284

return false;

327

285

}

328

286

329

287

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

330

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rc = gpgme_get_engine_info(&engine_info);

331

289

if(rc != GPG_ERR_NO_ERROR){

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

290

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

291

gpgme_strsource(rc), gpgme_strerror(rc));

334

292

return false;

335

293

}

336

294

while(engine_info != NULL){

342

300

engine_info = engine_info->next;

343

301

}

344

302

if(engine_info == NULL){

345

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

346

tempdir);

303

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

347

304

return false;

348

305

}

349

306

350

307

/* Create new GPGME "context" */

351

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

308

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

352

309

if(rc != GPG_ERR_NO_ERROR){

353

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

354

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

355

gpgme_strerror(rc));

310

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

311

gpgme_strsource(rc), gpgme_strerror(rc));

356

312

return false;

357

313

}

358

314

367

323

* Decrypt OpenPGP data.

368

324

* Returns -1 on error

369

325

*/

370

__attribute__((nonnull, warn_unused_result))

371

326

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

327

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

328

char **plaintext){

375

329

gpgme_data_t dh_crypto, dh_plain;

376

330

gpgme_error_t rc;

377

331

ssize_t ret;

379

333

ssize_t plaintext_length = 0;

380

334

381

335

if(debug){

382

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

336

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

383

337

}

384

338

385

339

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

386

340

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

387

341

0);

388

342

if(rc != GPG_ERR_NO_ERROR){

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

343

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

344

gpgme_strsource(rc), gpgme_strerror(rc));

391

345

return -1;

392

346

}

393

347

394

348

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

395

349

rc = gpgme_data_new(&dh_plain);

396

350

if(rc != GPG_ERR_NO_ERROR){

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

351

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

352

gpgme_strsource(rc), gpgme_strerror(rc));

400

353

gpgme_data_release(dh_crypto);

401

354

return -1;

402

355

}

403

356

404

357

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

405

358

data buffer */

406

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

359

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

407

360

if(rc != GPG_ERR_NO_ERROR){

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

361

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

362

gpgme_strsource(rc), gpgme_strerror(rc));

410

363

plaintext_length = -1;

411

364

if(debug){

412

365

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

366

result = gpgme_op_decrypt_result(mc.ctx);

414

367

if(result == NULL){

415

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

368

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

416

369

} else {

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

370

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

371

result->unsupported_algorithm);

372

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

373

result->wrong_key_usage);

421

374

if(result->file_name != NULL){

422

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

375

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

423

376

}

424

377

gpgme_recipient_t recipient;

425

378

recipient = result->recipients;

426

379

while(recipient != NULL){

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

380

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

381

gpgme_pubkey_algo_name(recipient->pubkey_algo));

382

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

383

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

384

recipient->status == GPG_ERR_NO_SECKEY

385

? "No" : "Yes");

434

386

recipient = recipient->next;

435

387

}

436

388

}

439

391

}

440

392

441

393

if(debug){

442

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

394

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

443

395

}

444

396

445

397

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

452

404

*plaintext = NULL;

453

405

while(true){

454

406

plaintext_capacity = incbuffer(plaintext,

455

(size_t)plaintext_length,

456

plaintext_capacity);

407

(size_t)plaintext_length,

408

plaintext_capacity);

457

409

if(plaintext_capacity == 0){

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

410

perror_plus("incbuffer");

411

plaintext_length = -1;

412

goto decrypt_end;

461

413

}

462

414

463

415

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

476

428

}

477

429

478

430

if(debug){

479

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

431

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

480

432

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

481

433

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

482

434

}

493

445

return plaintext_length;

494

446

}

495

447

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

448

static const char * safer_gnutls_strerror(int value){

449

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

450

-Wunreachable-code */

499

451

if(ret == NULL)

500

452

ret = "(unknown)";

501

453

return ret;

502

454

}

503

455

504

456

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

457

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

507

458

const char* string){

508

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

459

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

509

460

}

510

461

511

__attribute__((nonnull, warn_unused_result))

512

462

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

463

const char *seckeyfilename){

515

464

int ret;

516

465

517

466

if(debug){

518

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

467

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

519

468

}

520

469

521

470

ret = gnutls_global_init();

522

471

if(ret != GNUTLS_E_SUCCESS){

523

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

524

safer_gnutls_strerror(ret));

472

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

473

safer_gnutls_strerror(ret));

525

474

return -1;

526

475

}

527

476

534

483

}

535

484

536

485

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

486

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

487

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

488

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

489

safer_gnutls_strerror(ret));

541

490

gnutls_global_deinit();

542

491

return -1;

543

492

}

544

493

545

494

if(debug){

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

495

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

496

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

497

seckeyfilename);

550

498

}

551

499

552

500

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

501

(mc.cred, pubkeyfilename, seckeyfilename,

554

502

GNUTLS_OPENPGP_FMT_BASE64);

555

503

if(ret != GNUTLS_E_SUCCESS){

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

504

fprintf(stderr,

505

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

506

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

507

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

508

safer_gnutls_strerror(ret));

561

509

goto globalfail;

562

510

}

563

511

564

512

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

513

ret = gnutls_dh_params_init(&mc.dh_params);

566

514

if(ret != GNUTLS_E_SUCCESS){

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

515

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

516

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

570

517

goto globalfail;

571

518

}

572

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

519

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

573

520

if(ret != GNUTLS_E_SUCCESS){

574

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

575

safer_gnutls_strerror(ret));

521

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

522

safer_gnutls_strerror(ret));

576

523

goto globalfail;

577

524

}

578

525

579

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

526

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

527

581

528

return 0;

582

529

583

530

globalfail:

584

531

585

gnutls_certificate_free_credentials(mc->cred);

532

gnutls_certificate_free_credentials(mc.cred);

586

533

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

534

gnutls_dh_params_deinit(mc.dh_params);

588

535

return -1;

589

536

}

590

537

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

538

static int init_gnutls_session(gnutls_session_t *session){

594

539

int ret;

595

540

/* GnuTLS session creation */

596

541

do {

600

545

}

601

546

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

602

547

if(ret != GNUTLS_E_SUCCESS){

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

548

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

549

safer_gnutls_strerror(ret));

606

550

}

607

551

608

552

{

609

553

const char *err;

610

554

do {

611

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

555

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

612

556

if(quit_now){

613

557

gnutls_deinit(*session);

614

558

return -1;

615

559

}

616

560

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

617

561

if(ret != GNUTLS_E_SUCCESS){

618

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

619

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

620

safer_gnutls_strerror(ret));

562

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

563

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

564

safer_gnutls_strerror(ret));

621

565

gnutls_deinit(*session);

622

566

return -1;

623

567

}

625

569

626

570

do {

627

571

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

572

mc.cred);

629

573

if(quit_now){

630

574

gnutls_deinit(*session);

631

575

return -1;

632

576

}

633

577

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

634

578

if(ret != GNUTLS_E_SUCCESS){

635

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

636

safer_gnutls_strerror(ret));

579

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

580

safer_gnutls_strerror(ret));

637

581

gnutls_deinit(*session);

638

582

return -1;

639

583

}

641

585

/* ignore client certificate if any. */

642

586

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

587

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

588

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

589

646

590

return 0;

647

591

}

650

594

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

651

595

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

652

596

653

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

654

__attribute__((warn_unused_result))

655

error_t raise_privileges(void){

656

error_t old_errno = errno;

657

error_t ret_errno = 0;

658

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

659

ret_errno = errno;

660

}

661

errno = old_errno;

662

return ret_errno;

663

}

664

665

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

666

__attribute__((warn_unused_result))

667

error_t raise_privileges_permanently(void){

668

error_t old_errno = errno;

669

error_t ret_errno = raise_privileges();

670

if(ret_errno != 0){

671

errno = old_errno;

672

return ret_errno;

673

}

674

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

675

ret_errno = errno;

676

}

677

errno = old_errno;

678

return ret_errno;

679

}

680

681

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

682

__attribute__((warn_unused_result))

683

error_t lower_privileges(void){

684

error_t old_errno = errno;

685

error_t ret_errno = 0;

686

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

687

ret_errno = errno;

688

}

689

errno = old_errno;

690

return ret_errno;

691

}

692

693

/* Lower privileges permanently */

694

__attribute__((warn_unused_result))

695

error_t lower_privileges_permanently(void){

696

error_t old_errno = errno;

697

error_t ret_errno = 0;

698

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

699

ret_errno = errno;

700

}

701

errno = old_errno;

702

return ret_errno;

703

}

704

705

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

706

__attribute__((nonnull, warn_unused_result))

707

static bool add_remove_local_route(const bool add,

708

const char *address,

709

AvahiIfIndex if_index){

710

int ret;

711

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

712

char add_arg[] = "add";

713

char delete_arg[] = "delete";

714

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

715

if(pluginhelperdir == NULL){

716

if(debug){

717

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

718

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

719

}

720

return false;

721

}

722

723

char interface[IF_NAMESIZE];

724

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

725

perror_plus("if_indextoname");

726

return false;

727

}

728

729

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

730

if(devnull == -1){

731

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

732

return false;

733

}

734

pid_t pid = fork();

735

if(pid == 0){

736

/* Child */

737

/* Raise privileges */

738

errno = raise_privileges_permanently();

739

if(errno != 0){

740

perror_plus("Failed to raise privileges");

741

/* _exit(EX_NOPERM); */

742

} else {

743

/* Set group */

744

errno = 0;

745

ret = setgid(0);

746

if(ret == -1){

747

perror_plus("setgid");

748

_exit(EX_NOPERM);

749

}

750

/* Reset supplementary groups */

751

errno = 0;

752

ret = setgroups(0, NULL);

753

if(ret == -1){

754

perror_plus("setgroups");

755

_exit(EX_NOPERM);

756

}

757

}

758

ret = dup2(devnull, STDIN_FILENO);

759

if(ret == -1){

760

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

761

_exit(EX_OSERR);

762

}

763

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

764

if(ret == -1){

765

perror_plus("close");

766

_exit(EX_OSERR);

767

}

768

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

769

if(ret == -1){

770

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

771

_exit(EX_OSERR);

772

}

773

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

774

O_RDONLY

775

| O_DIRECTORY

776

| O_PATH

777

| O_CLOEXEC));

778

if(helperdir_fd == -1){

779

perror_plus("open");

780

_exit(EX_UNAVAILABLE);

781

}

782

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

783

helper, O_RDONLY));

784

if(helper_fd == -1){

785

perror_plus("openat");

786

_exit(EX_UNAVAILABLE);

787

}

788

TEMP_FAILURE_RETRY(close(helperdir_fd));

789

#ifdef __GNUC__

790

#pragma GCC diagnostic push

791

#pragma GCC diagnostic ignored "-Wcast-qual"

792

#endif

793

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

794

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

795

interface, NULL }, environ) == -1){

796

#ifdef __GNUC__

797

#pragma GCC diagnostic pop

798

#endif

799

perror_plus("fexecve");

800

_exit(EXIT_FAILURE);

801

}

802

}

803

if(pid == -1){

804

perror_plus("fork");

805

return false;

806

}

807

int status;

808

pid_t pret = -1;

809

errno = 0;

810

do {

811

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

812

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

813

int errno_raising = 0;

814

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

815

errno_raising = errno;

816

perror_plus("Failed to raise privileges in order to"

817

" kill helper program");

818

}

819

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

820

perror_plus("kill");

821

}

822

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

823

perror_plus("Failed to lower privileges after killing"

824

" helper program");

825

}

826

return false;

827

}

828

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

829

if(pret == -1){

830

perror_plus("waitpid");

831

return false;

832

}

833

if(WIFEXITED(status)){

834

if(WEXITSTATUS(status) != 0){

835

fprintf_plus(stderr, "Error: iprouteadddel exited"

836

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

837

return false;

838

}

839

return true;

840

}

841

if(WIFSIGNALED(status)){

842

fprintf_plus(stderr, "Error: iprouteadddel died by"

843

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

844

return false;

845

}

846

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

847

return false;

848

}

849

850

__attribute__((nonnull, warn_unused_result))

851

static bool add_local_route(const char *address,

852

AvahiIfIndex if_index){

853

return add_remove_local_route(true, address, if_index);

854

}

855

856

__attribute__((nonnull, warn_unused_result))

857

static bool remove_local_route(const char *address,

858

AvahiIfIndex if_index){

859

return add_remove_local_route(false, address, if_index);

860

}

861

862

597

/* Called when a Mandos server is found */

863

__attribute__((nonnull, warn_unused_result))

864

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

598

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

865

599

AvahiIfIndex if_index,

866

int af, mandos_context *mc){

600

int af){

867

601

int ret, tcp_sd = -1;

868

602

ssize_t sret;

869

struct sockaddr_storage to;

603

union {

604

struct sockaddr_in in;

605

struct sockaddr_in6 in6;

606

} to;

870

607

char *buffer = NULL;

871

608

char *decrypted_buffer = NULL;

872

609

size_t buffer_length = 0;

875

612

int retval = -1;

876

613

gnutls_session_t session;

877

614

int pf; /* Protocol family */

878

bool route_added = false;

879

615

880

616

errno = 0;

881

617

892

628

pf = PF_INET;

893

629

break;

894

630

default:

895

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

631

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

896

632

errno = EINVAL;

897

633

return -1;

898

634

}

899

635

900

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

901

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

902

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

903

bool match = false;

904

{

905

char *interface = NULL;

906

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

907

interface))){

908

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

909

match = true;

910

break;

911

}

912

}

913

}

914

if(not match){

915

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

916

connect to the server */

917

if(debug){

918

char interface[IF_NAMESIZE];

919

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

920

perror_plus("if_indextoname");

921

} else {

922

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

923

" \"%s\"\n",

924

if_indextoname((unsigned int)if_index,

925

interface));

926

}

927

}

928

return -1;

929

}

930

}

931

932

ret = init_gnutls_session(&session, mc);

636

ret = init_gnutls_session(&session);

933

637

if(ret != 0){

934

638

return -1;

935

639

}

936

640

937

641

if(debug){

938

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

939

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

642

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

643

"\n", ip, port);

940

644

}

941

645

942

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

646

tcp_sd = socket(pf, SOCK_STREAM, 0);

943

647

if(tcp_sd < 0){

944

648

int e = errno;

945

649

perror_plus("socket");

954

658

955

659

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

956

660

if(af == AF_INET6){

957

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

958

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

661

to.in6.sin6_family = (sa_family_t)af;

662

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

959

663

} else { /* IPv4 */

960

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

961

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

664

to.in.sin_family = (sa_family_t)af;

665

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

962

666

}

963

667

if(ret < 0 ){

964

668

int e = errno;

968

672

}

969

673

if(ret == 0){

970

674

int e = errno;

971

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

675

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

972

676

errno = e;

973

677

goto mandos_end;

974

678

}

975

679

if(af == AF_INET6){

976

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

977

if(IN6_IS_ADDR_LINKLOCAL

978

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

680

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

681

-Wconversion and

682

-Wunreachable-code */

683

684

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

685

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

686

-Wunreachable-code*/

979

687

if(if_index == AVAHI_IF_UNSPEC){

980

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

981

" incomplete without a network interface\n");

688

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

689

" without a network interface\n");

982

690

errno = EINVAL;

983

691

goto mandos_end;

984

692

}

985

693

/* Set the network interface number as scope */

986

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

694

to.in6.sin6_scope_id = (uint32_t)if_index;

987

695

}

988

696

} else {

989

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

697

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

698

-Wconversion and

699

-Wunreachable-code */

990

700

}

991

701

992

702

if(quit_now){

1000

710

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

1001

711

perror_plus("if_indextoname");

1002

712

} else {

1003

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

1004

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

713

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

714

ip, interface, port);

1005

715

}

1006

716

} else {

1007

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

1008

ip, (uintmax_t)port);

717

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

718

port);

1009

719

}

1010

720

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1011

721

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1012

if(af == AF_INET6){

1013

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

1014

sizeof(struct sockaddr_in6),

1015

addrstr, sizeof(addrstr), NULL, 0,

1016

NI_NUMERICHOST);

1017

} else {

1018

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

1019

sizeof(struct sockaddr_in),

1020

addrstr, sizeof(addrstr), NULL, 0,

1021

NI_NUMERICHOST);

1022

}

1023

if(ret == EAI_SYSTEM){

1024

perror_plus("getnameinfo");

1025

} else if(ret != 0) {

1026

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

1027

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

1028

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

1029

}

1030

}

1031

1032

if(quit_now){

1033

errno = EINTR;

1034

goto mandos_end;

1035

}

1036

1037

while(true){

1038

if(af == AF_INET6){

1039

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

1040

sizeof(struct sockaddr_in6));

1041

} else {

1042

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

1043

sizeof(struct sockaddr_in));

1044

}

1045

if(ret < 0){

1046

if(errno == ENETUNREACH

1047

and if_index != AVAHI_IF_UNSPEC

1048

and connect_to == NULL

1049

and not route_added and

1050

((af == AF_INET6 and not

1051

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1052

&to)->sin6_addr)))

1053

or (af == AF_INET and

1054

/* Not a a IPv4LL address */

1055

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

1056

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

1057

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

1058

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

1059

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

1060

connect to a Mandos server announced by Avahi on a server

1061

host with a global address. Work around this by retrying

1062

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

1063

1064

Avahi bug reference:

1065

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

1066

https://bugs.debian.org/587961

1067

*/

1068

int e = errno;

1069

route_added = add_local_route(ip, if_index);

1070

if(route_added){

1071

continue;

1072

}

1073

errno = e;

1074

}

1075

if(errno != ECONNREFUSED or debug){

1076

int e = errno;

1077

perror_plus("connect");

1078

errno = e;

1079

}

1080

goto mandos_end;

1081

}

1082

1083

if(quit_now){

1084

errno = EINTR;

1085

goto mandos_end;

1086

}

1087

break;

722

const char *pcret;

723

if(af == AF_INET6){

724

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

725

sizeof(addrstr));

726

} else {

727

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

728

sizeof(addrstr));

729

}

730

if(pcret == NULL){

731

perror_plus("inet_ntop");

732

} else {

733

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

734

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

735

}

736

}

737

}

738

739

if(quit_now){

740

errno = EINTR;

741

goto mandos_end;

742

}

743

744

if(af == AF_INET6){

745

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

746

} else {

747

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

748

}

749

if(ret < 0){

750

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

751

int e = errno;

752

perror_plus("connect");

753

errno = e;

754

}

755

goto mandos_end;

756

}

757

758

if(quit_now){

759

errno = EINTR;

760

goto mandos_end;

1088

761

}

1089

762

1090

763

const char *out = mandos_protocol_version;

1092

765

while(true){

1093

766

size_t out_size = strlen(out);

1094

767

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

1095

out_size - written));

768

out_size - written));

1096

769

if(ret == -1){

1097

770

int e = errno;

1098

771

perror_plus("write");

1118

791

}

1119

792

1120

793

if(debug){

1121

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

794

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

1122

795

}

1123

796

1124

797

if(quit_now){

1126

799

goto mandos_end;

1127

800

}

1128

801

1129

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

1130

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

1131

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

1132

gnutls_transport_set_ptr(session,

1133

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

802

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

803

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1134

804

1135

805

if(quit_now){

1136

806

errno = EINTR;

1147

817

1148

818

if(ret != GNUTLS_E_SUCCESS){

1149

819

if(debug){

1150

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

820

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

1151

821

gnutls_perror(ret);

1152

822

}

1153

823

errno = EPROTO;

1157

827

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

1158

828

1159

829

if(debug){

1160

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1161

" %s\n", ip);

830

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

831

ip);

1162

832

}

1163

833

1164

834

while(true){

1169

839

}

1170

840

1171

841

buffer_capacity = incbuffer(&buffer, buffer_length,

1172

buffer_capacity);

842

buffer_capacity);

1173

843

if(buffer_capacity == 0){

1174

844

int e = errno;

1175

845

perror_plus("incbuffer");

1202

872

}

1203

873

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

1204

874

if(ret < 0){

1205

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

1206

"***\n");

875

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

1207

876

gnutls_perror(ret);

1208

877

errno = EPROTO;

1209

878

goto mandos_end;

1210

879

}

1211

880

break;

1212

881

default:

1213

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

1214

" encrypted session with Mandos server\n");

882

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

883

" encrypted session with Mandos server\n");

1215

884

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1216

885

errno = EIO;

1217

886

goto mandos_end;

1222

891

}

1223

892

1224

893

if(debug){

1225

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

894

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

1226

895

}

1227

896

1228

897

if(quit_now){

1240

909

1241

910

if(buffer_length > 0){

1242

911

ssize_t decrypted_buffer_size;

1243

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1244

&decrypted_buffer, mc);

912

decrypted_buffer_size = pgp_packet_decrypt(buffer,

913

buffer_length,

914

&decrypted_buffer);

1245

915

if(decrypted_buffer_size >= 0){

1246

916

1247

917

written = 0;

1257

927

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

1258

928

int e = errno;

1259

929

if(debug){

1260

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

1261

strerror(errno));

930

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

931

strerror(errno));

1262

932

}

1263

933

errno = e;

1264

934

goto mandos_end;

1273

943

1274

944

mandos_end:

1275

945

{

1276

if(route_added){

1277

if(not remove_local_route(ip, if_index)){

1278

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

1279

" interface %d", ip, if_index);

1280

}

1281

}

1282

946

int e = errno;

1283

947

free(decrypted_buffer);

1284

948

free(buffer);

1301

965

return retval;

1302

966

}

1303

967

1304

__attribute__((nonnull))

1305

968

static void resolve_callback(AvahiSServiceResolver *r,

1306

969

AvahiIfIndex interface,

1307

970

AvahiProtocol proto,

1315

978

AVAHI_GCC_UNUSED AvahiStringList *txt,

1316

979

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1317

980

flags,

1318

void *mc){

1319

if(r == NULL){

1320

return;

1321

}

981

AVAHI_GCC_UNUSED void* userdata){

982

assert(r);

1322

983

1323

984

/* Called whenever a service has been resolved successfully or

1324

985

timed out */

1325

986

1326

987

if(quit_now){

1327

avahi_s_service_resolver_free(r);

1328

988

return;

1329

989

}

1330

990

1331

991

switch(event){

1332

992

default:

1333

993

case AVAHI_RESOLVER_FAILURE:

1334

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

1335

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

1336

domain,

1337

avahi_strerror(avahi_server_errno

1338

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

994

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

995

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

996

avahi_strerror(avahi_server_errno(mc.server)));

1339

997

break;

1340

998

1341

999

case AVAHI_RESOLVER_FOUND:

1343

1001

char ip[AVAHI_ADDRESS_STR_MAX];

1344

1002

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

1345

1003

if(debug){

1346

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

1347

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

1348

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

1004

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

1005

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

1006

ip, (intmax_t)interface, port);

1349

1007

}

1350

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

1351

interface,

1352

avahi_proto_to_af(proto),

1353

mc);

1008

int ret = start_mandos_communication(ip, port, interface,

1009

avahi_proto_to_af(proto));

1354

1010

if(ret == 0){

1355

avahi_simple_poll_quit(simple_poll);

1011

avahi_simple_poll_quit(mc.simple_poll);

1356

1012

} else {

1357

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

1358

avahi_proto_to_af(proto),

1359

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

1360

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

1361

" list\n", name);

1362

}

1013

ret = add_server(ip, port, interface,

1014

avahi_proto_to_af(proto));

1363

1015

}

1364

1016

}

1365

1017

}

1375

1027

const char *domain,

1376

1028

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1377

1029

flags,

1378

void *mc){

1379

if(b == NULL){

1380

return;

1381

}

1030

AVAHI_GCC_UNUSED void* userdata){

1031

assert(b);

1382

1032

1383

1033

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

1384

1034

is removed from the LAN */

1391

1041

default:

1392

1042

case AVAHI_BROWSER_FAILURE:

1393

1043

1394

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

1395

avahi_strerror(avahi_server_errno

1396

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

1397

avahi_simple_poll_quit(simple_poll);

1044

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

1045

avahi_strerror(avahi_server_errno(mc.server)));

1046

avahi_simple_poll_quit(mc.simple_poll);

1398

1047

return;

1399

1048

1400

1049

case AVAHI_BROWSER_NEW:

1403

1052

the callback function is called the Avahi server will free the

1404

1053

resolver for us. */

1405

1054

1406

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

1407

interface, protocol, name, type,

1408

domain, protocol, 0,

1409

resolve_callback, mc) == NULL)

1410

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

1411

" %s\n", name,

1412

avahi_strerror(avahi_server_errno

1413

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

1055

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

1056

name, type, domain, protocol, 0,

1057

resolve_callback, NULL) == NULL)

1058

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

1059

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

1414

1060

break;

1415

1061

1416

1062

case AVAHI_BROWSER_REMOVE:

1419

1065

case AVAHI_BROWSER_ALL_FOR_NOW:

1420

1066

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1421

1067

if(debug){

1422

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

1423

" searching...\n");

1068

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

1424

1069

}

1425

1070

break;

1426

1071

}

1435

1080

signal_received = sig;

1436

1081

int old_errno = errno;

1437

1082

/* set main loop to exit */

1438

if(simple_poll != NULL){

1439

avahi_simple_poll_quit(simple_poll);

1083

if(mc.simple_poll != NULL){

1084

avahi_simple_poll_quit(mc.simple_poll);

1440

1085

}

1441

1086

errno = old_errno;

1442

1087

}

1443

1088

1444

__attribute__((nonnull, warn_unused_result))

1445

1089

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

1446

1090

int ret;

1447

error_t ret_errno;

1448

1091

1449

1092

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

1450

1093

if(s < 0){

1451

ret_errno = errno;

1452

1094

perror_plus("socket");

1453

errno = ret_errno;

1454

1095

return false;

1455

1096

}

1456

1097

strcpy(ifr->ifr_name, ifname);

1457

1098

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1458

1099

if(ret == -1){

1459

1100

if(debug){

1460

ret_errno = errno;

1461

1101

perror_plus("ioctl SIOCGIFFLAGS");

1462

errno = ret_errno;

1463

1102

}

1464

1103

return false;

1465

1104

}

1466

1105

return true;

1467

1106

}

1468

1107

1469

__attribute__((nonnull, warn_unused_result))

1470

1108

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

1471

1109

1472

1110

/* Reject the loopback device */

1473

1111

if(ifr->ifr_flags & IFF_LOOPBACK){

1474

1112

if(debug){

1475

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

1476

ifname);

1113

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

1114

ifname);

1477

1115

}

1478

1116

return false;

1479

1117

}

1480

1118

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

1481

1119

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

1482

1120

if(debug){

1483

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

1484

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

1121

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

1122

ifname);

1485

1123

}

1486

1124

return true;

1487

1125

}

1488

1126

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

1489

1127

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

1490

1128

if(debug){

1491

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1492

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

1129

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

1130

ifname);

1493

1131

}

1494

1132

return false;

1495

1133

}

1496

1134

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

1497

1135

if(ifr->ifr_flags & IFF_NOARP){

1498

1136

if(debug){

1499

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

1500

ifname);

1137

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

1501

1138

}

1502

1139

return false;

1503

1140

}

1504

1141

1505

1142

/* Accept this device */

1506

1143

if(debug){

1507

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

1144

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

1508

1145

}

1509

1146

return true;

1510

1147

}

1514

1151

* corresponds to an acceptable network device.

1515

1152

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

1516

1153

*/

1517

__attribute__((nonnull, warn_unused_result))

1518

1154

int good_interface(const struct dirent *if_entry){

1519

1155

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

1520

1156

return 0;

1523

1159

struct ifreq ifr;

1524

1160

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

1525

1161

if(debug){

1526

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

1527

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

1528

}

1529

return 0;

1530

}

1531

1532

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

1533

return 0;

1534

}

1535

return 1;

1536

}

1537

1538

/*

1539

* This function determines if a network interface is up.

1540

*/

1541

__attribute__((nonnull, warn_unused_result))

1542

bool interface_is_up(const char *interface){

1543

struct ifreq ifr;

1544

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

1545

if(debug){

1546

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

1547

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

1548

}

1549

return false;

1550

}

1551

1552

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

1553

}

1554

1555

/*

1556

* This function determines if a network interface is running

1557

*/

1558

__attribute__((nonnull, warn_unused_result))

1559

bool interface_is_running(const char *interface){

1560

struct ifreq ifr;

1561

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

1562

if(debug){

1563

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

1564

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

1565

}

1566

return false;

1567

}

1568

1569

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

1570

}

1571

1572

__attribute__((nonnull, pure, warn_unused_result))

1162

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

1163

if_entry->d_name);

1164

}

1165

return 0;

1166

}

1167

1168

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

1169

return 0;

1170

}

1171

return 1;

1172

}

1173

1174

/*

1175

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

1176

* corresponds to an acceptable network device which is up.

1177

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

1178

*/

1179

int up_interface(const struct dirent *if_entry){

1180

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

1181

return 0;

1182

}

1183

1184

struct ifreq ifr;

1185

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

1186

if(debug){

1187

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

1188

if_entry->d_name);

1189

}

1190

return 0;

1191

}

1192

1193

/* Reject down interfaces */

1194

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

1195

if(debug){

1196

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

1197

if_entry->d_name);

1198

}

1199

return 0;

1200

}

1201

1202

/* Reject non-running interfaces */

1203

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

1204

if(debug){

1205

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

1206

if_entry->d_name);

1207

}

1208

return 0;

1209

}

1210

1211

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

1212

return 0;

1213

}

1214

return 1;

1215

}

1216

1573

1217

int notdotentries(const struct dirent *direntry){

1574

1218

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

1575

1219

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

1582

1226

}

1583

1227

1584

1228

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

1585

__attribute__((nonnull, warn_unused_result))

1586

1229

int runnable_hook(const struct dirent *direntry){

1587

1230

int ret;

1588

size_t sret;

1589

1231

struct stat st;

1590

1232

1591

1233

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

1593

1235

return 0;

1594

1236

}

1595

1237

1596

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

1597

"abcdefghijklmnopqrstuvwxyz"

1598

"0123456789"

1599

"_.-");

1600

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

1601

/* Contains non-allowed characters */

1602

if(debug){

1603

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

1604

direntry->d_name);

1605

}

1606

return 0;

1607

}

1608

1609

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

1238

/* Save pointer to last character */

1239

char *end = strchr(direntry->d_name, '\0')-1;

1240

1241

if(*end == '~'){

1242

/* Backup name~ */

1243

return 0;

1244

}

1245

1246

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

1247

and (*end == '#')){

1248

/* Temporary #name# */

1249

return 0;

1250

}

1251

1252

/* XXX more rules here */

1253

1254

ret = stat(direntry->d_name, &st);

1610

1255

if(ret == -1){

1611

1256

if(debug){

1612

perror_plus("Could not stat hook");

1257

perror_plus("Could not stat plugin");

1613

1258

}

1614

1259

return 0;

1615

1260

}

1616

1261

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

1617

1262

/* Not a regular file */

1618

if(debug){

1619

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

1620

direntry->d_name);

1621

}

1622

1263

return 0;

1623

1264

}

1624

1265

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

1625

1266

/* Not executable */

1626

if(debug){

1627

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

1628

direntry->d_name);

1629

}

1630

1267

return 0;

1631

1268

}

1632

if(debug){

1633

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

1634

direntry->d_name);

1635

}

1636

1269

return 1;

1637

1270

}

1638

1271

1639

__attribute__((nonnull, warn_unused_result))

1640

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1641

mandos_context *mc){

1272

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1642

1273

int ret;

1643

1274

struct timespec now;

1644

1275

struct timespec waited_time;

1645

1276

intmax_t block_time;

1646

1277

1647

1278

while(true){

1648

if(mc->current_server == NULL){

1649

if(debug){

1650

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

1651

" No timeout!\n");

1279

if(mc.current_server == NULL){

1280

if (debug){

1281

fprintf(stderr,

1282

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

1652

1283

}

1653

1284

ret = avahi_simple_poll_iterate(s, -1);

1654

1285

} else {

1655

if(debug){

1656

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

1657

" it, or wait\n");

1286

if (debug){

1287

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

1288

" or wait\n");

1658

1289

}

1659

1290

/* the current time */

1660

1291

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1665

1296

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

1666

1297

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

1667

1298

waited_time.tv_sec = (now.tv_sec

1668

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

1299

- mc.current_server->last_seen.tv_sec);

1669

1300

waited_time.tv_nsec = (now.tv_nsec

1670

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

1301

- mc.current_server->last_seen.tv_nsec);

1671

1302

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

1672

1303

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

1673

1304

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

1675

1306

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

1676

1307

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

1677

1308

1678

if(debug){

1679

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

1680

block_time);

1309

if (debug){

1310

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

1681

1311

}

1682

1312

1683

1313

if(block_time <= 0){

1684

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

1685

mc->current_server->port,

1686

mc->current_server->if_index,

1687

mc->current_server->af, mc);

1314

ret = start_mandos_communication(mc.current_server->ip,

1315

mc.current_server->port,

1316

mc.current_server->if_index,

1317

mc.current_server->af);

1688

1318

if(ret == 0){

1689

avahi_simple_poll_quit(s);

1319

avahi_simple_poll_quit(mc.simple_poll);

1690

1320

return 0;

1691

1321

}

1692

1322

ret = clock_gettime(CLOCK_MONOTONIC,

1693

&mc->current_server->last_seen);

1323

&mc.current_server->last_seen);

1694

1324

if(ret == -1){

1695

1325

perror_plus("clock_gettime");

1696

1326

return -1;

1697

1327

}

1698

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

1328

mc.current_server = mc.current_server->next;

1699

1329

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

1700

1330

servers, but don't block */

1701

1331

}

1703

1333

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

1704

1334

}

1705

1335

if(ret != 0){

1706

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

1336

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

1707

1337

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

1708

1338

}

1709

1339

}

1710

1340

}

1711

1341

}

1712

1342

1713

__attribute__((nonnull))

1714

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

1715

const float delay){

1716

struct dirent **direntries = NULL;

1717

if(hookdir_fd == -1){

1718

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1719

| O_CLOEXEC);

1720

if(hookdir_fd == -1){

1721

if(errno == ENOENT){

1722

if(debug){

1723

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

1724

" found\n", hookdir);

1725

}

1726

} else {

1727

perror_plus("open");

1728

}

1729

return;

1730

}

1731

}

1732

#ifdef __GLIBC__

1733

#if __GLIBC_PREREQ(2, 15)

1734

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

1735

runnable_hook, alphasort);

1736

#else /* not __GLIBC_PREREQ(2, 15) */

1737

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

1738

alphasort);

1739

#endif /* not __GLIBC_PREREQ(2, 15) */

1740

#else /* not __GLIBC__ */

1741

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

1742

alphasort);

1743

#endif /* not __GLIBC__ */

1744

if(numhooks == -1){

1745

perror_plus("scandir");

1746

return;

1747

}

1748

struct dirent *direntry;

1749

int ret;

1750

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

1751

if(devnull == -1){

1752

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

1753

return;

1754

}

1755

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

1756

direntry = direntries[i];

1757

if(debug){

1758

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

1759

direntry->d_name);

1760

}

1761

pid_t hook_pid = fork();

1762

if(hook_pid == 0){

1763

/* Child */

1764

/* Raise privileges */

1765

errno = raise_privileges_permanently();

1766

if(errno != 0){

1767

perror_plus("Failed to raise privileges");

1768

_exit(EX_NOPERM);

1769

}

1770

/* Set group */

1771

errno = 0;

1772

ret = setgid(0);

1773

if(ret == -1){

1774

perror_plus("setgid");

1775

_exit(EX_NOPERM);

1776

}

1777

/* Reset supplementary groups */

1778

errno = 0;

1779

ret = setgroups(0, NULL);

1780

if(ret == -1){

1781

perror_plus("setgroups");

1782

_exit(EX_NOPERM);

1783

}

1784

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

1785

if(ret == -1){

1786

perror_plus("setenv");

1787

_exit(EX_OSERR);

1788

}

1789

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

1790

if(ret == -1){

1791

perror_plus("setenv");

1792

_exit(EX_OSERR);

1793

}

1794

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

1795

if(ret == -1){

1796

perror_plus("setenv");

1797

_exit(EX_OSERR);

1798

}

1799

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

1800

if(ret == -1){

1801

perror_plus("setenv");

1802

_exit(EX_OSERR);

1803

}

1804

char *delaystring;

1805

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

1806

if(ret == -1){

1807

perror_plus("asprintf");

1808

_exit(EX_OSERR);

1809

}

1810

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

1811

if(ret == -1){

1812

free(delaystring);

1813

perror_plus("setenv");

1814

_exit(EX_OSERR);

1815

}

1816

free(delaystring);

1817

if(connect_to != NULL){

1818

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

1819

if(ret == -1){

1820

perror_plus("setenv");

1821

_exit(EX_OSERR);

1822

}

1823

}

1824

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

1825

direntry->d_name,

1826

O_RDONLY));

1827

if(hook_fd == -1){

1828

perror_plus("openat");

1829

_exit(EXIT_FAILURE);

1830

}

1831

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

1832

perror_plus("close");

1833

_exit(EXIT_FAILURE);

1834

}

1835

ret = dup2(devnull, STDIN_FILENO);

1836

if(ret == -1){

1837

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

1838

_exit(EX_OSERR);

1839

}

1840

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

1841

if(ret == -1){

1842

perror_plus("close");

1843

_exit(EX_OSERR);

1844

}

1845

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1846

if(ret == -1){

1847

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

1848

_exit(EX_OSERR);

1849

}

1850

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

1851

environ) == -1){

1852

perror_plus("fexecve");

1853

_exit(EXIT_FAILURE);

1854

}

1855

} else {

1856

if(hook_pid == -1){

1857

perror_plus("fork");

1858

free(direntry);

1859

continue;

1860

}

1861

int status;

1862

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

1863

perror_plus("waitpid");

1864

free(direntry);

1865

continue;

1866

}

1867

if(WIFEXITED(status)){

1868

if(WEXITSTATUS(status) != 0){

1869

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

1870

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

1871

WEXITSTATUS(status));

1872

free(direntry);

1873

continue;

1874

}

1875

} else if(WIFSIGNALED(status)){

1876

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

1877

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

1878

WTERMSIG(status));

1879

free(direntry);

1880

continue;

1881

} else {

1882

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

1883

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

1884

free(direntry);

1885

continue;

1886

}

1887

}

1888

if(debug){

1889

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

1890

direntry->d_name);

1891

}

1892

free(direntry);

1893

}

1894

free(direntries);

1895

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

1896

perror_plus("close");

1897

} else {

1898

hookdir_fd = -1;

1899

}

1900

close(devnull);

1901

}

1902

1903

__attribute__((nonnull, warn_unused_result))

1904

error_t bring_up_interface(const char *const interface,

1905

const float delay){

1906

error_t old_errno = errno;

1907

int ret;

1908

struct ifreq network;

1909

unsigned int if_index = if_nametoindex(interface);

1910

if(if_index == 0){

1911

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

1912

errno = old_errno;

1913

return ENXIO;

1914

}

1915

1916

if(quit_now){

1917

errno = old_errno;

1918

return EINTR;

1919

}

1920

1921

if(not interface_is_up(interface)){

1922

error_t ret_errno = 0, ioctl_errno = 0;

1923

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

1924

ret_errno = errno;

1925

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

1926

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

1927

errno = old_errno;

1928

return ret_errno;

1929

}

1930

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

1931

1932

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

1933

if(sd == -1){

1934

ret_errno = errno;

1935

perror_plus("socket");

1936

errno = old_errno;

1937

return ret_errno;

1938

}

1939

1940

if(quit_now){

1941

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

1942

if(ret == -1){

1943

perror_plus("close");

1944

}

1945

errno = old_errno;

1946

return EINTR;

1947

}

1948

1949

if(debug){

1950

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

1951

interface);

1952

}

1953

1954

/* Raise privileges */

1955

ret_errno = raise_privileges();

1956

if(ret_errno != 0){

1957

errno = ret_errno;

1958

perror_plus("Failed to raise privileges");

1959

}

1960

1961

#ifdef __linux__

1962

int ret_linux;

1963

bool restore_loglevel = false;

1964

if(ret_errno == 0){

1965

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1966

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

1967

ret_linux = klogctl(8, NULL, 5);

1968

if(ret_linux == -1){

1969

perror_plus("klogctl");

1970

} else {

1971

restore_loglevel = true;

1972

}

1973

}

1974

#endif /* __linux__ */

1975

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

1976

ioctl_errno = errno;

1977

#ifdef __linux__

1978

if(restore_loglevel){

1979

ret_linux = klogctl(7, NULL, 0);

1980

if(ret_linux == -1){

1981

perror_plus("klogctl");

1982

}

1983

}

1984

#endif /* __linux__ */

1985

1986

/* If raise_privileges() succeeded above */

1987

if(ret_errno == 0){

1988

/* Lower privileges */

1989

ret_errno = lower_privileges();

1990

if(ret_errno != 0){

1991

errno = ret_errno;

1992

perror_plus("Failed to lower privileges");

1993

}

1994

}

1995

1996

/* Close the socket */

1997

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

1998

if(ret == -1){

1999

perror_plus("close");

2000

}

2001

2002

if(ret_setflags == -1){

2003

errno = ioctl_errno;

2004

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2005

errno = old_errno;

2006

return ioctl_errno;

2007

}

2008

} else if(debug){

2009

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

2010

interface);

2011

}

2012

2013

/* Sleep checking until interface is running.

2014

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

2015

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

2016

if(interface_is_running(interface)){

2017

break;

2018

}

2019

struct timespec sleeptime = { .tv_nsec = 250000000 };

2020

ret = nanosleep(&sleeptime, NULL);

2021

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

2022

perror_plus("nanosleep");

2023

}

2024

}

2025

2026

errno = old_errno;

2027

return 0;

2028

}

2029

2030

__attribute__((nonnull, warn_unused_result))

2031

error_t take_down_interface(const char *const interface){

2032

error_t old_errno = errno;

2033

struct ifreq network;

2034

unsigned int if_index = if_nametoindex(interface);

2035

if(if_index == 0){

2036

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

2037

errno = old_errno;

2038

return ENXIO;

2039

}

2040

if(interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

2043

ret_errno = errno;

2044

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

2045

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

2046

errno = old_errno;

2047

return ret_errno;

2048

}

2049

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

2050

2051

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

2052

if(sd == -1){

2053

ret_errno = errno;

2054

perror_plus("socket");

2055

errno = old_errno;

2056

return ret_errno;

2057

}

2058

2059

if(debug){

2060

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

2061

interface);

2062

}

2063

2064

/* Raise privileges */

2065

ret_errno = raise_privileges();

2066

if(ret_errno != 0){

2067

errno = ret_errno;

2068

perror_plus("Failed to raise privileges");

2069

}

2070

2071

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

2072

ioctl_errno = errno;

2073

2074

/* If raise_privileges() succeeded above */

2075

if(ret_errno == 0){

2076

/* Lower privileges */

2077

ret_errno = lower_privileges();

2078

if(ret_errno != 0){

2079

errno = ret_errno;

2080

perror_plus("Failed to lower privileges");

2081

}

2082

}

2083

2084

/* Close the socket */

2085

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

2086

if(ret == -1){

2087

perror_plus("close");

2088

}

2089

2090

if(ret_setflags == -1){

2091

errno = ioctl_errno;

2092

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2093

errno = old_errno;

2094

return ioctl_errno;

2095

}

2096

} else if(debug){

2097

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

2098

interface);

2099

}

2100

2101

errno = old_errno;

2102

return 0;

2103

}

2104

2105

1343

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

2106

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

2107

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

2108

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

2109

.interfaces = NULL, .interfaces_size = 0 };

2110

1344

AvahiSServiceBrowser *sb = NULL;

2111

error_t ret_errno;

1345

int error;

2112

1346

int ret;

2113

1347

intmax_t tmpmax;

2114

1348

char *tmp;

2115

1349

int exitcode = EXIT_SUCCESS;

2116

char *interfaces_to_take_down = NULL;

2117

size_t interfaces_to_take_down_size = 0;

2118

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

2119

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

2120

char *tempdir = NULL;

1350

const char *interface = "";

1351

struct ifreq network;

1352

int sd = -1;

1353

bool take_down_interface = false;

1354

uid_t uid;

1355

gid_t gid;

1356

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

1357

bool tempdir_created = false;

2121

1358

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2122

1359

const char *seckey = PATHDIR "/" SECKEY;

2123

1360

const char *pubkey = PATHDIR "/" PUBKEY;

2124

char *interfaces_hooks = NULL;

2125

1361

2126

1362

bool gnutls_initialized = false;

2127

1363

bool gpgme_initialized = false;

2189

1425

.group = 2 },

2190

1426

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

2191

1427

.arg = "SECONDS",

2192

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

2193

.group = 2 },

2194

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

2195

.arg = "DIR",

2196

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

1428

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

2197

1429

.group = 2 },

2198

1430

/*

2199

1431

* These reproduce what we would get without ARGP_NO_HELP

2218

1450

connect_to = arg;

2219

1451

break;

2220

1452

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

2221

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

2222

arg, (int)',');

2223

if(ret_errno != 0){

2224

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

2225

}

1453

interface = arg;

2226

1454

break;

2227

1455

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

2228

1456

seckey = arg;

2257

1485

argp_error(state, "Bad retry interval");

2258

1486

}

2259

1487

break;

2260

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

2261

hookdir = arg;

2262

break;

2263

1488

/*

2264

1489

* These reproduce what we would get without ARGP_NO_HELP

2265

1490

*/

2271

1496

argp_state_help(state, state->out_stream,

2272

1497

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2273

1498

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

2274

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

1499

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

2275

1500

exit(argp_err_exit_status);

2276

1501

break;

2277

1502

default:

2300

1525

goto end;

2301

1526

}

2302

1527

}

2303

1528

2304

1529

{

2305

1530

/* Work around Debian bug #633582:

2306

1531

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

2307

2308

/* Re-raise privileges */

2309

ret_errno = raise_privileges();

2310

if(ret_errno != 0){

2311

errno = ret_errno;

2312

perror_plus("Failed to raise privileges");

2313

} else {

2314

struct stat st;

2315

2316

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

2317

int seckey_fd = open(seckey, O_RDONLY);

2318

if(seckey_fd == -1){

2319

perror_plus("open");

2320

} else {

2321

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

2322

if(ret == -1){

2323

perror_plus("fstat");

2324

} else {

2325

if(S_ISREG(st.st_mode)

2326

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

2327

ret = fchown(seckey_fd, uid, gid);

2328

if(ret == -1){

2329

perror_plus("fchown");

2330

}

2331

}

2332

}

2333

TEMP_FAILURE_RETRY(close(seckey_fd));

2334

}

2335

}

2336

2337

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

2338

int pubkey_fd = open(pubkey, O_RDONLY);

2339

if(pubkey_fd == -1){

2340

perror_plus("open");

2341

} else {

2342

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

2343

if(ret == -1){

2344

perror_plus("fstat");

2345

} else {

2346

if(S_ISREG(st.st_mode)

2347

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

2348

ret = fchown(pubkey_fd, uid, gid);

2349

if(ret == -1){

2350

perror_plus("fchown");

2351

}

2352

}

2353

}

2354

TEMP_FAILURE_RETRY(close(pubkey_fd));

2355

}

2356

}

2357

2358

/* Lower privileges */

2359

ret_errno = lower_privileges();

2360

if(ret_errno != 0){

2361

errno = ret_errno;

2362

perror_plus("Failed to lower privileges");

2363

}

2364

}

2365

}

2366

2367

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

2368

{

2369

char *interface = NULL;

2370

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

2371

interface))){

2372

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

2373

and if_nametoindex(interface) == 0){

2374

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

2375

fprintf_plus(stderr, "Not using nonexisting interface"

2376

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

2377

}

2378

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

2379

interface = NULL;

2380

}

2381

}

2382

}

2383

2384

/* Run network hooks */

2385

{

2386

if(mc.interfaces != NULL){

2387

interfaces_hooks = malloc(mc.interfaces_size);

2388

if(interfaces_hooks == NULL){

2389

perror_plus("malloc");

1532

struct stat st;

1533

1534

/* Re-raise priviliges */

1535

errno = 0;

1536

ret = seteuid(0);

1537

if(ret == -1){

1538

perror_plus("seteuid");

1539

}

1540

1541

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

1542

int seckey_fd = open(seckey, O_RDONLY);

1543

if(seckey_fd == -1){

1544

perror_plus("open");

1545

} else {

1546

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

1547

if(ret == -1){

1548

perror_plus("fstat");

1549

} else {

1550

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

1551

ret = fchown(seckey_fd, uid, gid);

1552

if(ret == -1){

1553

perror_plus("fchown");

1554

}

1555

}

1556

}

1557

TEMP_FAILURE_RETRY(close(seckey_fd));

1558

}

1559

}

1560

1561

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

1562

int pubkey_fd = open(pubkey, O_RDONLY);

1563

if(pubkey_fd == -1){

1564

perror_plus("open");

1565

} else {

1566

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

1567

if(ret == -1){

1568

perror_plus("fstat");

1569

} else {

1570

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

1571

ret = fchown(pubkey_fd, uid, gid);

1572

if(ret == -1){

1573

perror_plus("fchown");

1574

}

1575

}

1576

}

1577

TEMP_FAILURE_RETRY(close(pubkey_fd));

1578

}

1579

}

1580

1581

/* Lower privileges */

1582

errno = 0;

1583

ret = seteuid(uid);

1584

if(ret == -1){

1585

perror_plus("seteuid");

1586

}

1587

}

1588

1589

/* Find network hooks and run them */

1590

{

1591

struct dirent **direntries;

1592

struct dirent *direntry;

1593

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

1594

alphasort);

1595

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

1596

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

1597

direntry = direntries[0];

1598

char *fullname = NULL;

1599

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

1600

direntry->d_name);

1601

if(ret < 0){

1602

perror_plus("asprintf");

1603

continue;

1604

}

1605

pid_t hook_pid = fork();

1606

if(hook_pid == 0){

1607

/* Child */

1608

dup2(devnull, STDIN_FILENO);

1609

close(devnull);

1610

dup2(STDERR_FILENO, STDOUT_FILENO);

1611

setenv("DEVICE", interface, 1);

1612

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

1613

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

1614

/* setenv( XXX more here */

1615

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

1616

perror_plus("execl");

1617

}

1618

free(fullname);

1619

if(quit_now){

2390

1620

goto end;

2391

1621

}

2392

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

2393

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

2394

1622

}

2395

run_network_hooks("start", interfaces_hooks != NULL ?

2396

interfaces_hooks : "", delay);

1623

close(devnull);

2397

1624

}

2398

1625

2399

1626

if(not debug){

2400

1627

avahi_set_log_function(empty_log);

2401

1628

}

2402

1629

1630

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

1631

struct dirent **direntries;

1632

/* First look for interfaces that are up */

1633

ret = scandir(sys_class_net, &direntries, up_interface,

1634

alphasort);

1635

if(ret == 0){

1636

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

1637

free(direntries);

1638

ret = scandir(sys_class_net, &direntries, good_interface,

1639

alphasort);

1640

}

1641

if(ret >= 1){

1642

/* Pick the first interface returned */

1643

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

1644

if(debug){

1645

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

1646

}

1647

if(interface == NULL){

1648

perror_plus("malloc");

1649

free(direntries);

1650

exitcode = EXIT_FAILURE;

1651

goto end;

1652

}

1653

free(direntries);

1654

} else {

1655

free(direntries);

1656

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

1657

exitcode = EXIT_FAILURE;

1658

goto end;

1659

}

1660

}

1661

2403

1662

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

2404

1663

from the signal handler */

2405

1664

/* Initialize the pseudo-RNG for Avahi */

2406

1665

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

2407

simple_poll = avahi_simple_poll_new();

2408

if(simple_poll == NULL){

2409

fprintf_plus(stderr,

2410

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

1666

mc.simple_poll = avahi_simple_poll_new();

1667

if(mc.simple_poll == NULL){

1668

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

2411

1669

exitcode = EX_UNAVAILABLE;

2412

1670

goto end;

2413

1671

}

2475

1733

}

2476

1734

}

2477

1735

2478

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

2479

if(mc.interfaces == NULL){

2480

struct dirent **direntries = NULL;

2481

/* Look for any good interfaces */

2482

ret = scandir(sys_class_net, &direntries, good_interface,

2483

alphasort);

2484

if(ret >= 1){

2485

/* Add all found interfaces to interfaces list */

2486

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

2487

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

2488

direntries[i]->d_name);

2489

if(ret_errno != 0){

2490

errno = ret_errno;

2491

perror_plus("argz_add");

2492

free(direntries[i]);

2493

continue;

2494

}

2495

if(debug){

2496

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

2497

direntries[i]->d_name);

2498

}

2499

free(direntries[i]);

2500

}

2501

free(direntries);

1736

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

1737

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

1738

if_index = (AvahiIfIndex) if_nametoindex(interface);

1739

if(if_index == 0){

1740

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

1741

exitcode = EX_UNAVAILABLE;

1742

goto end;

1743

}

1744

1745

if(quit_now){

1746

goto end;

1747

}

1748

1749

/* Re-raise priviliges */

1750

errno = 0;

1751

ret = seteuid(0);

1752

if(ret == -1){

1753

perror_plus("seteuid");

1754

}

1755

1756

#ifdef __linux__

1757

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1758

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

1759

ret = klogctl(8, NULL, 5);

1760

bool restore_loglevel = true;

1761

if(ret == -1){

1762

restore_loglevel = false;

1763

perror_plus("klogctl");

1764

}

1765

#endif /* __linux__ */

1766

1767

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1768

if(sd < 0){

1769

perror_plus("socket");

1770

exitcode = EX_OSERR;

1771

#ifdef __linux__

1772

if(restore_loglevel){

1773

ret = klogctl(7, NULL, 0);

1774

if(ret == -1){

1775

perror_plus("klogctl");

1776

}

1777

}

1778

#endif /* __linux__ */

1779

/* Lower privileges */

1780

errno = 0;

1781

ret = seteuid(uid);

1782

if(ret == -1){

1783

perror_plus("seteuid");

1784

}

1785

goto end;

1786

}

1787

strcpy(network.ifr_name, interface);

1788

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

1789

if(ret == -1){

1790

perror_plus("ioctl SIOCGIFFLAGS");

1791

#ifdef __linux__

1792

if(restore_loglevel){

1793

ret = klogctl(7, NULL, 0);

1794

if(ret == -1){

1795

perror_plus("klogctl");

1796

}

1797

}

1798

#endif /* __linux__ */

1799

exitcode = EX_OSERR;

1800

/* Lower privileges */

1801

errno = 0;

1802

ret = seteuid(uid);

1803

if(ret == -1){

1804

perror_plus("seteuid");

1805

}

1806

goto end;

1807

}

1808

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

1809

network.ifr_flags |= IFF_UP;

1810

take_down_interface = true;

1811

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

1812

if(ret == -1){

1813

take_down_interface = false;

1814

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1815

exitcode = EX_OSERR;

1816

#ifdef __linux__

1817

if(restore_loglevel){

1818

ret = klogctl(7, NULL, 0);

1819

if(ret == -1){

1820

perror_plus("klogctl");

1821

}

1822

}

1823

#endif /* __linux__ */

1824

/* Lower privileges */

1825

errno = 0;

1826

ret = seteuid(uid);

1827

if(ret == -1){

1828

perror_plus("seteuid");

1829

}

1830

goto end;

1831

}

1832

}

1833

/* Sleep checking until interface is running.

1834

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

1835

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

1836

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

1837

if(ret == -1){

1838

perror_plus("ioctl SIOCGIFFLAGS");

1839

} else if(network.ifr_flags & IFF_RUNNING){

1840

break;

1841

}

1842

struct timespec sleeptime = { .tv_nsec = 250000000 };

1843

ret = nanosleep(&sleeptime, NULL);

1844

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

1845

perror_plus("nanosleep");

1846

}

1847

}

1848

if(not take_down_interface){

1849

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

1850

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

1851

if(ret == -1){

1852

perror_plus("close");

1853

}

1854

}

1855

#ifdef __linux__

1856

if(restore_loglevel){

1857

/* Restores kernel loglevel to default */

1858

ret = klogctl(7, NULL, 0);

1859

if(ret == -1){

1860

perror_plus("klogctl");

1861

}

1862

}

1863

#endif /* __linux__ */

1864

/* Lower privileges */

1865

errno = 0;

1866

if(take_down_interface){

1867

/* Lower privileges */

1868

ret = seteuid(uid);

1869

if(ret == -1){

1870

perror_plus("seteuid");

1871

}

2502

1872

} else {

2503

if(ret == 0){

2504

free(direntries);

2505

}

2506

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

2507

exitcode = EXIT_FAILURE;

2508

goto end;

2509

}

2510

}

2511

2512

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

2513

{

2514

char *interface = NULL;

2515

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

2516

interface))){

2517

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

2518

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

2519

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

2520

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

2521

interface);

2522

interface = NULL;

2523

while((interface = argz_next(mc.interfaces,

2524

mc.interfaces_size, interface))){

2525

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

2526

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

2527

interface);

2528

interface = NULL;

2529

}

2530

}

2531

break;

2532

}

2533

bool interface_was_up = interface_is_up(interface);

2534

errno = bring_up_interface(interface, delay);

2535

if(not interface_was_up){

2536

if(errno != 0){

2537

perror_plus("Failed to bring up interface");

2538

} else {

2539

errno = argz_add(&interfaces_to_take_down,

2540

&interfaces_to_take_down_size,

2541

interface);

2542

if(errno != 0){

2543

perror_plus("argz_add");

2544

}

2545

}

2546

}

2547

}

2548

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

2549

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

2550

}

2551

}

2552

2553

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

2554

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

2555

if(debug){

2556

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

2557

mc.interfaces);

2558

}

2559

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

1873

/* Lower privileges permanently */

1874

ret = setuid(uid);

1875

if(ret == -1){

1876

perror_plus("setuid");

1877

}

1878

}

2560

1879

}

2561

1880

2562

1881

if(quit_now){

2563

1882

goto end;

2564

1883

}

2565

1884

2566

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

1885

ret = init_gnutls_global(pubkey, seckey);

2567

1886

if(ret == -1){

2568

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

1887

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

2569

1888

exitcode = EX_UNAVAILABLE;

2570

1889

goto end;

2571

1890

} else {

2576

1895

goto end;

2577

1896

}

2578

1897

2579

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

2580

tempdir = mkdtemp(run_tempdir);

2581

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

2582

if(debug){

2583

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

2584

run_tempdir, old_tempdir);

2585

}

2586

tempdir = mkdtemp(old_tempdir);

2587

}

2588

if(tempdir == NULL){

1898

if(mkdtemp(tempdir) == NULL){

2589

1899

perror_plus("mkdtemp");

2590

1900

goto end;

2591

1901

}

1902

tempdir_created = true;

2592

1903

2593

1904

if(quit_now){

2594

1905

goto end;

2595

1906

}

2596

1907

2597

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

2598

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

1908

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

1909

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

2599

1910

exitcode = EX_UNAVAILABLE;

2600

1911

goto end;

2601

1912

} else {

2610

1921

/* Connect directly, do not use Zeroconf */

2611

1922

/* (Mainly meant for debugging) */

2612

1923

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

2613

2614

1924

if(address == NULL){

2615

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

1925

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

2616

1926

exitcode = EX_USAGE;

2617

1927

goto end;

2618

1928

}

2621

1931

goto end;

2622

1932

}

2623

1933

2624

in_port_t port;

1934

uint16_t port;

2625

1935

errno = 0;

2626

1936

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

2627

1937

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

2628

or tmpmax != (in_port_t)tmpmax){

2629

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

1938

or tmpmax != (uint16_t)tmpmax){

1939

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

2630

1940

exitcode = EX_USAGE;

2631

1941

goto end;

2632

1942

}

2633

1943

2634

1944

if(quit_now){

2635

1945

goto end;

2636

1946

}

2637

1947

2638

port = (in_port_t)tmpmax;

1948

port = (uint16_t)tmpmax;

2639

1949

*address = '\0';

2640

1950

/* Colon in address indicates IPv6 */

2641

1951

int af;

2657

1967

}

2658

1968

2659

1969

while(not quit_now){

2660

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

2661

&mc);

1970

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

2662

1971

if(quit_now or ret == 0){

2663

1972

break;

2664

1973

}

2665

1974

if(debug){

2666

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

2667

(int)retry_interval);

1975

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

1976

(int)retry_interval);

2668

1977

}

2669

sleep((unsigned int)retry_interval);

1978

sleep((int)retry_interval);

2670

1979

}

2671

1980

2672

if(not quit_now){

1981

if (not quit_now){

2673

1982

exitcode = EXIT_SUCCESS;

2674

1983

}

2675

1984

2690

1999

config.publish_domain = 0;

2691

2000

2692

2001

/* Allocate a new server */

2693

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2694

&config, NULL, NULL, &ret_errno);

2002

mc.server = avahi_server_new(avahi_simple_poll_get

2003

(mc.simple_poll), &config, NULL,

2004

NULL, &error);

2695

2005

2696

2006

/* Free the Avahi configuration data */

2697

2007

avahi_server_config_free(&config);

2699

2009

2700

2010

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

2701

2011

if(mc.server == NULL){

2702

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

2703

avahi_strerror(ret_errno));

2012

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

2013

avahi_strerror(error));

2704

2014

exitcode = EX_UNAVAILABLE;

2705

2015

goto end;

2706

2016

}

2712

2022

/* Create the Avahi service browser */

2713

2023

sb = avahi_s_service_browser_new(mc.server, if_index,

2714

2024

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2715

NULL, 0, browse_callback,

2716

(void *)&mc);

2025

NULL, 0, browse_callback, NULL);

2717

2026

if(sb == NULL){

2718

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

2719

avahi_strerror(avahi_server_errno(mc.server)));

2027

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

2028

avahi_strerror(avahi_server_errno(mc.server)));

2720

2029

exitcode = EX_UNAVAILABLE;

2721

2030

goto end;

2722

2031

}

2728

2037

/* Run the main loop */

2729

2038

2730

2039

if(debug){

2731

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

2040

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

2732

2041

}

2733

2734

ret = avahi_loop_with_timeout(simple_poll,

2735

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

2042

2043

ret = avahi_loop_with_timeout(mc.simple_poll,

2044

(int)(retry_interval * 1000));

2736

2045

if(debug){

2737

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

2738

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

2046

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

2047

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

2739

2048

}

2740

2049

2741

2050

end:

2742

2051

2743

2052

if(debug){

2744

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

2053

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

2745

2054

}

2746

2055

2747

2056

/* Cleanup things */

2748

free(mc.interfaces);

2749

2750

2057

if(sb != NULL)

2751

2058

avahi_s_service_browser_free(sb);

2752

2059

2753

2060

if(mc.server != NULL)

2754

2061

avahi_server_free(mc.server);

2755

2062

2756

if(simple_poll != NULL)

2757

avahi_simple_poll_free(simple_poll);

2063

if(mc.simple_poll != NULL)

2064

avahi_simple_poll_free(mc.simple_poll);

2758

2065

2759

2066

if(gnutls_initialized){

2760

2067

gnutls_certificate_free_credentials(mc.cred);

2765

2072

if(gpgme_initialized){

2766

2073

gpgme_release(mc.ctx);

2767

2074

}

2768

2075

2769

2076

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

2770

2077

has seen */

2771

2078

if(mc.current_server != NULL){

2772

2079

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

2773

2080

while(mc.current_server != NULL){

2774

2081

server *next = mc.current_server->next;

2775

#ifdef __GNUC__

2776

#pragma GCC diagnostic push

2777

#pragma GCC diagnostic ignored "-Wcast-qual"

2778

#endif

2779

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

2780

#ifdef __GNUC__

2781

#pragma GCC diagnostic pop

2782

#endif

2783

2082

free(mc.current_server);

2784

2083

mc.current_server = next;

2785

2084

}

2786

2085

}

2787

2086

2788

/* Re-raise privileges */

2789

{

2790

ret_errno = raise_privileges();

2791

if(ret_errno != 0){

2792

errno = ret_errno;

2793

perror_plus("Failed to raise privileges");

2794

} else {

2795

2796

/* Run network hooks */

2797

run_network_hooks("stop", interfaces_hooks != NULL ?

2798

interfaces_hooks : "", delay);

2799

2800

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

2801

{

2802

char *interface = NULL;

2803

while((interface=argz_next(interfaces_to_take_down,

2804

interfaces_to_take_down_size,

2805

interface))){

2806

ret_errno = take_down_interface(interface);

2807

if(ret_errno != 0){

2808

errno = ret_errno;

2809

perror_plus("Failed to take down interface");

2810

}

2811

}

2812

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

2813

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

2814

" down\n");

2815

}

2816

}

2087

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

2088

2089

/* Take down the network interface */

2090

if(take_down_interface){

2091

/* Re-raise priviliges */

2092

errno = 0;

2093

ret = seteuid(0);

2094

if(ret == -1){

2095

perror_plus("seteuid");

2817

2096

}

2818

2819

ret_errno = lower_privileges_permanently();

2820

if(ret_errno != 0){

2821

errno = ret_errno;

2822

perror_plus("Failed to lower privileges permanently");

2097

if(geteuid() == 0){

2098

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

2099

if(ret == -1){

2100

perror_plus("ioctl SIOCGIFFLAGS");

2101

} else if(network.ifr_flags & IFF_UP) {

2102

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

2103

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

2104

if(ret == -1){

2105

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2106

}

2107

}

2108

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

2109

if(ret == -1){

2110

perror_plus("close");

2111

}

2112

/* Lower privileges permanently */

2113

errno = 0;

2114

ret = setuid(uid);

2115

if(ret == -1){

2116

perror_plus("setuid");

2117

}

2823

2118

}

2824

2119

}

2825

2120

2826

free(interfaces_to_take_down);

2827

free(interfaces_hooks);

2828

2829

2121

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

2830

if(tempdir != NULL){

2122

if(tempdir_created){

2831

2123

struct dirent **direntries = NULL;

2832

int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY

2833

| O_NOFOLLOW

2834

| O_DIRECTORY

2835

| O_PATH));

2836

if(tempdir_fd == -1){

2837

perror_plus("open");

2838

} else {

2839

#ifdef __GLIBC__

2840

#if __GLIBC_PREREQ(2, 15)

2841

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

2842

notdotentries, alphasort);

2843

#else /* not __GLIBC_PREREQ(2, 15) */

2844

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

2845

alphasort);

2846

#endif /* not __GLIBC_PREREQ(2, 15) */

2847

#else /* not __GLIBC__ */

2848

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

2849

alphasort);

2850

#endif /* not __GLIBC__ */

2851

if(numentries >= 0){

2852

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

2853

ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);

2854

if(ret == -1){

2855

fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"

2856

" \"%s\", 0): %s\n", tempdir,

2857

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

2858

}

2859

free(direntries[i]);

2860

}

2861

2862

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

2863

free(direntries);

2864

if(numentries == -1){

2865

perror_plus("scandir");

2866

}

2867

ret = rmdir(tempdir);

2868

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

2869

perror_plus("rmdir");

2870

}

2124

struct dirent *direntry = NULL;

2125

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

2126

alphasort);

2127

if (numentries > 0){

2128

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

2129

direntry = direntries[i];

2130

char *fullname = NULL;

2131

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

2132

direntry->d_name);

2133

if(ret < 0){

2134

perror_plus("asprintf");

2135

continue;

2136

}

2137

ret = remove(fullname);

2138

if(ret == -1){

2139

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

2140

strerror(errno));

2141

}

2142

free(fullname);

2871

2143

}

2872

TEMP_FAILURE_RETRY(close(tempdir_fd));

2144

}

2145

2146

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

2147

free(direntries);

2148

if (numentries == -1){

2149

perror_plus("scandir");

2150

}

2151

ret = rmdir(tempdir);

2152

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

2153

perror_plus("rmdir");

2873

2154

}

2874

2155

}

2875

2156