/mandos/release : revision 237.15.4

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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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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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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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*/

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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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#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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139

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 {

148

AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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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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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;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

191

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va_start (ap, format);

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177

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

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program_invocation_short_name));

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

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

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

196

180

}

197

181

198

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/*

200

184

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

201

185

* "buffer_length" is how much is already used.

202

186

*/

203

__attribute__((nonnull, warn_unused_result))

204

187

size_t incbuffer(char **buffer, size_t buffer_length,

205

size_t buffer_capacity){

188

size_t buffer_capacity){

206

189

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;

190

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

191

if(buffer == NULL){

213

192

return 0;

214

193

}

215

*buffer = new_buf;

216

194

buffer_capacity += BUFFER_SIZE;

217

195

}

218

196

return buffer_capacity;

219

197

}

220

198

221

199

/* 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,

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int af, server **current_server){

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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int ret;

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

227

205

if(new_server == NULL){

228

206

perror_plus("malloc");

229

return false;

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return -1;

230

208

}

231

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

235

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if(new_server->ip == NULL){

236

214

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#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;

215

return -1;

253

216

}

254

217

/* Special case of first server */

255

if(*current_server == NULL){

218

if (mc.current_server == NULL){

256

219

new_server->next = new_server;

257

220

new_server->prev = new_server;

258

*current_server = new_server;

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mc.current_server = new_server;

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

259

223

} else {

260

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

261

new_server->next = *current_server;

262

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

224

new_server->next = mc.current_server;

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

263

226

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

227

mc.current_server->prev = new_server;

228

}

229

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

230

if(ret == -1){

231

perror_plus("clock_gettime");

232

return -1;

233

}

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return 0;

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235

}

268

236

269

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/*

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238

* Initialize GPGME.

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239

*/

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__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){

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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242

gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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245

280

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/*

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

282

248

*/

283

bool import_key(const char * const filename){

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bool import_key(const char *filename){

284

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int ret;

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int fd;

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252

gpgme_data_t pgp_data;

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259

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

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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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return false;

299

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}

300

266

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

267

rc = gpgme_op_import(mc.ctx, pgp_data);

302

268

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));

269

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

270

gpgme_strsource(rc), gpgme_strerror(rc));

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271

return false;

306

272

}

307

273

314

280

}

315

281

316

282

if(debug){

317

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

283

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

318

284

}

319

285

320

286

/* Init GPGME */

321

287

gpgme_check_version(NULL);

322

288

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

323

289

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));

290

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

291

gpgme_strsource(rc), gpgme_strerror(rc));

326

292

return false;

327

293

}

328

294

329

295

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

330

296

rc = gpgme_get_engine_info(&engine_info);

331

297

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));

298

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

299

gpgme_strsource(rc), gpgme_strerror(rc));

334

300

return false;

335

301

}

336

302

while(engine_info != NULL){

342

308

engine_info = engine_info->next;

343

309

}

344

310

if(engine_info == NULL){

345

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

346

tempdir);

311

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

347

312

return false;

348

313

}

349

314

350

315

/* Create new GPGME "context" */

351

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

316

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

352

317

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));

318

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

319

gpgme_strsource(rc), gpgme_strerror(rc));

356

320

return false;

357

321

}

358

322

367

331

* Decrypt OpenPGP data.

368

332

* Returns -1 on error

369

333

*/

370

__attribute__((nonnull, warn_unused_result))

371

334

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

335

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

336

char **plaintext){

375

337

gpgme_data_t dh_crypto, dh_plain;

376

338

gpgme_error_t rc;

377

339

ssize_t ret;

379

341

ssize_t plaintext_length = 0;

380

342

381

343

if(debug){

382

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

344

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

383

345

}

384

346

385

347

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

386

348

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

387

349

0);

388

350

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));

351

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

352

gpgme_strsource(rc), gpgme_strerror(rc));

391

353

return -1;

392

354

}

393

355

394

356

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

395

357

rc = gpgme_data_new(&dh_plain);

396

358

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));

359

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

360

gpgme_strsource(rc), gpgme_strerror(rc));

400

361

gpgme_data_release(dh_crypto);

401

362

return -1;

402

363

}

403

364

404

365

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

405

366

data buffer */

406

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

367

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

407

368

if(rc != GPG_ERR_NO_ERROR){

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

410

371

plaintext_length = -1;

411

372

if(debug){

412

373

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

374

result = gpgme_op_decrypt_result(mc.ctx);

414

375

if(result == NULL){

415

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

376

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

416

377

} 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);

378

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

379

result->unsupported_algorithm);

380

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

381

result->wrong_key_usage);

421

382

if(result->file_name != NULL){

422

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

383

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

423

384

}

424

385

gpgme_recipient_t recipient;

425

386

recipient = result->recipients;

426

387

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");

388

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

389

gpgme_pubkey_algo_name(recipient->pubkey_algo));

390

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

391

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

392

recipient->status == GPG_ERR_NO_SECKEY

393

? "No" : "Yes");

434

394

recipient = recipient->next;

435

395

}

436

396

}

439

399

}

440

400

441

401

if(debug){

442

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

402

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

443

403

}

444

404

445

405

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

452

412

*plaintext = NULL;

453

413

while(true){

454

414

plaintext_capacity = incbuffer(plaintext,

455

(size_t)plaintext_length,

456

plaintext_capacity);

415

(size_t)plaintext_length,

416

plaintext_capacity);

457

417

if(plaintext_capacity == 0){

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

418

perror_plus("incbuffer");

419

plaintext_length = -1;

420

goto decrypt_end;

461

421

}

462

422

463

423

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

476

436

}

477

437

478

438

if(debug){

479

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

439

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

480

440

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

481

441

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

482

442

}

493

453

return plaintext_length;

494

454

}

495

455

496

__attribute__((warn_unused_result, const))

497

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

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

__attribute__((warn_unused_result))

504

static const char *safer_gnutls_strerror(int value){

505

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

456

static const char * safer_gnutls_strerror(int value){

457

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

458

-Wunreachable-code */

459

if(ret == NULL)

460

ret = "(unknown)";

461

return ret;

507

462

}

508

463

509

464

/* GnuTLS log function callback */

510

__attribute__((nonnull))

511

465

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

512

466

const char* string){

513

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

467

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

514

468

}

515

469

516

__attribute__((nonnull, warn_unused_result))

517

470

static int init_gnutls_global(const char *pubkeyfilename,

518

const char *seckeyfilename,

519

mandos_context *mc){

471

const char *seckeyfilename){

520

472

int ret;

521

unsigned int uret;

522

473

523

474

if(debug){

524

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

475

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

525

476

}

526

477

527

478

ret = gnutls_global_init();

528

479

if(ret != GNUTLS_E_SUCCESS){

529

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

530

safer_gnutls_strerror(ret));

480

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

481

safer_gnutls_strerror(ret));

531

482

return -1;

532

483

}

533

484

540

491

}

541

492

542

493

/* OpenPGP credentials */

543

ret = gnutls_certificate_allocate_credentials(&mc->cred);

494

ret = gnutls_certificate_allocate_credentials(&mc.cred);

544

495

if(ret != GNUTLS_E_SUCCESS){

545

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

546

safer_gnutls_strerror(ret));

496

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

497

safer_gnutls_strerror(ret));

547

498

gnutls_global_deinit();

548

499

return -1;

549

500

}

550

501

551

502

if(debug){

552

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

553

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

554

pubkeyfilename,

555

seckeyfilename);

503

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

504

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

505

seckeyfilename);

556

506

}

557

507

558

508

ret = gnutls_certificate_set_openpgp_key_file

559

(mc->cred, pubkeyfilename, seckeyfilename,

509

(mc.cred, pubkeyfilename, seckeyfilename,

560

510

GNUTLS_OPENPGP_FMT_BASE64);

561

511

if(ret != GNUTLS_E_SUCCESS){

562

fprintf_plus(stderr,

563

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

564

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

565

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

566

safer_gnutls_strerror(ret));

512

fprintf(stderr,

513

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

514

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

515

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

516

safer_gnutls_strerror(ret));

567

517

goto globalfail;

568

518

}

569

519

570

520

/* GnuTLS server initialization */

571

ret = gnutls_dh_params_init(&mc->dh_params);

521

ret = gnutls_dh_params_init(&mc.dh_params);

572

522

if(ret != GNUTLS_E_SUCCESS){

573

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

574

" initialization: %s\n",

575

safer_gnutls_strerror(ret));

523

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

524

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

576

525

goto globalfail;

577

526

}

578

if(mc->dh_bits == 0){

579

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

580

/* Try to read the private key file */

581

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

582

{

583

int secfile = open(seckeyfilename, O_RDONLY);

584

size_t buffer_capacity = 0;

585

while(true){

586

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

587

(size_t)buffer.size,

588

(size_t)buffer_capacity);

589

if(buffer_capacity == 0){

590

perror_plus("incbuffer");

591

free(buffer.data);

592

buffer.data = NULL;

593

break;

594

}

595

ssize_t bytes_read = read(secfile, buffer.data + buffer.size,

596

BUFFER_SIZE);

597

/* EOF */

598

if(bytes_read == 0){

599

break;

600

}

601

/* check bytes_read for failure */

602

if(bytes_read < 0){

603

perror_plus("read");

604

free(buffer.data);

605

buffer.data = NULL;

606

break;

607

}

608

buffer.size += (unsigned int)bytes_read;

609

}

610

close(secfile);

611

}

612

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

613

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

614

if(buffer.data != NULL){

615

{

616

gnutls_openpgp_privkey_t privkey = NULL;

617

ret = gnutls_openpgp_privkey_init(&privkey);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Error initializing OpenPGP key"

620

" structure: %s", safer_gnutls_strerror(ret));

621

free(buffer.data);

622

buffer.data = NULL;

623

} else {

624

ret = gnutls_openpgp_privkey_import(privkey, &buffer,

625

GNUTLS_OPENPGP_FMT_BASE64,

626

"", 0);

627

if(ret != GNUTLS_E_SUCCESS){

628

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

629

safer_gnutls_strerror(ret));

630

privkey = NULL;

631

}

632

free(buffer.data);

633

buffer.data = NULL;

634

if(privkey != NULL){

635

/* Use private key to suggest an appropriate sec_param */

636

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

637

gnutls_openpgp_privkey_deinit(privkey);

638

if(debug){

639

fprintf_plus(stderr, "This OpenPGP key implies using a"

640

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

641

safe_string(gnutls_sec_param_get_name

642

(sec_param)));

643

}

644

}

645

}

646

}

647

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

648

/* Err on the side of caution */

649

sec_param = GNUTLS_SEC_PARAM_ULTRA;

650

if(debug){

651

fprintf_plus(stderr, "Falling back to security parameter"

652

" \"%s\"\n",

653

safe_string(gnutls_sec_param_get_name

654

(sec_param)));

655

}

656

}

657

}

658

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

659

if(uret != 0){

660

mc->dh_bits = uret;

661

if(debug){

662

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

663

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

664

safe_string(gnutls_sec_param_get_name

665

(sec_param)),

666

mc->dh_bits);

667

}

668

} else {

669

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

670

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

671

safe_string(gnutls_sec_param_get_name(sec_param)),

672

safer_gnutls_strerror(ret));

673

goto globalfail;

674

}

675

} else if(debug){

676

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

677

mc->dh_bits);

678

}

679

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

527

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

680

528

if(ret != GNUTLS_E_SUCCESS){

681

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

682

" %s\n", mc->dh_bits, safer_gnutls_strerror(ret));

529

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

530

safer_gnutls_strerror(ret));

683

531

goto globalfail;

684

532

}

685

533

686

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

534

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

687

535

688

536

return 0;

689

537

690

538

globalfail:

691

539

692

gnutls_certificate_free_credentials(mc->cred);

540

gnutls_certificate_free_credentials(mc.cred);

693

541

gnutls_global_deinit();

694

gnutls_dh_params_deinit(mc->dh_params);

542

gnutls_dh_params_deinit(mc.dh_params);

695

543

return -1;

696

544

}

697

545

698

__attribute__((nonnull, warn_unused_result))

699

static int init_gnutls_session(gnutls_session_t *session,

700

mandos_context *mc){

546

static int init_gnutls_session(gnutls_session_t *session){

701

547

int ret;

702

548

/* GnuTLS session creation */

703

549

do {

707

553

}

708

554

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

709

555

if(ret != GNUTLS_E_SUCCESS){

710

fprintf_plus(stderr,

711

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

712

safer_gnutls_strerror(ret));

556

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

557

safer_gnutls_strerror(ret));

713

558

}

714

559

715

560

{

716

561

const char *err;

717

562

do {

718

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

563

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

719

564

if(quit_now){

720

565

gnutls_deinit(*session);

721

566

return -1;

722

567

}

723

568

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

724

569

if(ret != GNUTLS_E_SUCCESS){

725

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

726

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

727

safer_gnutls_strerror(ret));

570

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

571

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

572

safer_gnutls_strerror(ret));

728

573

gnutls_deinit(*session);

729

574

return -1;

730

575

}

732

577

733

578

do {

734

579

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

735

mc->cred);

580

mc.cred);

736

581

if(quit_now){

737

582

gnutls_deinit(*session);

738

583

return -1;

739

584

}

740

585

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

741

586

if(ret != GNUTLS_E_SUCCESS){

742

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

743

safer_gnutls_strerror(ret));

587

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

588

safer_gnutls_strerror(ret));

744

589

gnutls_deinit(*session);

745

590

return -1;

746

591

}

748

593

/* ignore client certificate if any. */

749

594

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

750

595

751

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

596

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

752

597

753

598

return 0;

754

599

}

757

602

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

758

603

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

759

604

760

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

761

__attribute__((warn_unused_result))

762

error_t raise_privileges(void){

763

error_t old_errno = errno;

764

error_t ret_errno = 0;

765

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

766

ret_errno = errno;

767

}

768

errno = old_errno;

769

return ret_errno;

770

}

771

772

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

773

__attribute__((warn_unused_result))

774

error_t raise_privileges_permanently(void){

775

error_t old_errno = errno;

776

error_t ret_errno = raise_privileges();

777

if(ret_errno != 0){

778

errno = old_errno;

779

return ret_errno;

780

}

781

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

782

ret_errno = errno;

783

}

784

errno = old_errno;

785

return ret_errno;

786

}

787

788

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

789

__attribute__((warn_unused_result))

790

error_t lower_privileges(void){

791

error_t old_errno = errno;

792

error_t ret_errno = 0;

793

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

794

ret_errno = errno;

795

}

796

errno = old_errno;

797

return ret_errno;

798

}

799

800

/* Lower privileges permanently */

801

__attribute__((warn_unused_result))

802

error_t lower_privileges_permanently(void){

803

error_t old_errno = errno;

804

error_t ret_errno = 0;

805

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

806

ret_errno = errno;

807

}

808

errno = old_errno;

809

return ret_errno;

810

}

811

812

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

813

__attribute__((nonnull, warn_unused_result))

814

static bool add_delete_local_route(const bool add,

815

const char *address,

816

AvahiIfIndex if_index){

817

int ret;

818

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

819

char add_arg[] = "add";

820

char delete_arg[] = "delete";

821

char debug_flag[] = "--debug";

822

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

823

if(pluginhelperdir == NULL){

824

if(debug){

825

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

826

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

827

}

828

return false;

829

}

830

831

char interface[IF_NAMESIZE];

832

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

833

perror_plus("if_indextoname");

834

return false;

835

}

836

837

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

838

if(devnull == -1){

839

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

840

return false;

841

}

842

pid_t pid = fork();

843

if(pid == 0){

844

/* Child */

845

/* Raise privileges */

846

errno = raise_privileges_permanently();

847

if(errno != 0){

848

perror_plus("Failed to raise privileges");

849

/* _exit(EX_NOPERM); */

850

} else {

851

/* Set group */

852

errno = 0;

853

ret = setgid(0);

854

if(ret == -1){

855

perror_plus("setgid");

856

_exit(EX_NOPERM);

857

}

858

/* Reset supplementary groups */

859

errno = 0;

860

ret = setgroups(0, NULL);

861

if(ret == -1){

862

perror_plus("setgroups");

863

_exit(EX_NOPERM);

864

}

865

}

866

ret = dup2(devnull, STDIN_FILENO);

867

if(ret == -1){

868

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

869

_exit(EX_OSERR);

870

}

871

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

872

if(ret == -1){

873

perror_plus("close");

874

_exit(EX_OSERR);

875

}

876

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

877

if(ret == -1){

878

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

879

_exit(EX_OSERR);

880

}

881

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

882

O_RDONLY

883

| O_DIRECTORY

884

| O_PATH

885

| O_CLOEXEC));

886

if(helperdir_fd == -1){

887

perror_plus("open");

888

_exit(EX_UNAVAILABLE);

889

}

890

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

891

helper, O_RDONLY));

892

if(helper_fd == -1){

893

perror_plus("openat");

894

_exit(EX_UNAVAILABLE);

895

}

896

TEMP_FAILURE_RETRY(close(helperdir_fd));

897

#ifdef __GNUC__

898

#pragma GCC diagnostic push

899

#pragma GCC diagnostic ignored "-Wcast-qual"

900

#endif

901

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

902

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

903

interface, debug ? debug_flag : NULL, NULL },

904

environ) == -1){

905

#ifdef __GNUC__

906

#pragma GCC diagnostic pop

907

#endif

908

perror_plus("fexecve");

909

_exit(EXIT_FAILURE);

910

}

911

}

912

if(pid == -1){

913

perror_plus("fork");

914

return false;

915

}

916

int status;

917

pid_t pret = -1;

918

errno = 0;

919

do {

920

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

921

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

922

int errno_raising = 0;

923

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

924

errno_raising = errno;

925

perror_plus("Failed to raise privileges in order to"

926

" kill helper program");

927

}

928

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

929

perror_plus("kill");

930

}

931

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

932

perror_plus("Failed to lower privileges after killing"

933

" helper program");

934

}

935

return false;

936

}

937

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

938

if(pret == -1){

939

perror_plus("waitpid");

940

return false;

941

}

942

if(WIFEXITED(status)){

943

if(WEXITSTATUS(status) != 0){

944

fprintf_plus(stderr, "Error: iprouteadddel exited"

945

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

946

return false;

947

}

948

return true;

949

}

950

if(WIFSIGNALED(status)){

951

fprintf_plus(stderr, "Error: iprouteadddel died by"

952

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

953

return false;

954

}

955

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

956

return false;

957

}

958

959

__attribute__((nonnull, warn_unused_result))

960

static bool add_local_route(const char *address,

961

AvahiIfIndex if_index){

962

if(debug){

963

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

964

}

965

return add_delete_local_route(true, address, if_index);

966

}

967

968

__attribute__((nonnull, warn_unused_result))

969

static bool delete_local_route(const char *address,

970

AvahiIfIndex if_index){

971

if(debug){

972

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

973

}

974

return add_delete_local_route(false, address, if_index);

975

}

976

977

605

/* Called when a Mandos server is found */

978

__attribute__((nonnull, warn_unused_result))

979

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

606

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

980

607

AvahiIfIndex if_index,

981

int af, mandos_context *mc){

608

int af){

982

609

int ret, tcp_sd = -1;

983

610

ssize_t sret;

984

struct sockaddr_storage to;

611

union {

612

struct sockaddr_in in;

613

struct sockaddr_in6 in6;

614

} to;

985

615

char *buffer = NULL;

986

616

char *decrypted_buffer = NULL;

987

617

size_t buffer_length = 0;

990

620

int retval = -1;

991

621

gnutls_session_t session;

992

622

int pf; /* Protocol family */

993

bool route_added = false;

994

623

995

624

errno = 0;

996

625

1007

636

pf = PF_INET;

1008

637

break;

1009

638

default:

1010

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

639

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

1011

640

errno = EINVAL;

1012

641

return -1;

1013

642

}

1014

643

1015

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

1016

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

1017

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

1018

bool match = false;

1019

{

1020

char *interface = NULL;

1021

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

1022

interface))){

1023

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

1024

match = true;

1025

break;

1026

}

1027

}

1028

}

1029

if(not match){

1030

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

1031

connect to the server */

1032

if(debug){

1033

char interface[IF_NAMESIZE];

1034

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

1035

perror_plus("if_indextoname");

1036

} else {

1037

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

1038

" \"%s\"\n",

1039

if_indextoname((unsigned int)if_index,

1040

interface));

1041

}

1042

}

1043

return -1;

1044

}

1045

}

1046

1047

ret = init_gnutls_session(&session, mc);

644

ret = init_gnutls_session(&session);

1048

645

if(ret != 0){

1049

646

return -1;

1050

647

}

1051

648

1052

649

if(debug){

1053

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

1054

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

650

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

651

"\n", ip, port);

1055

652

}

1056

653

1057

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

654

tcp_sd = socket(pf, SOCK_STREAM, 0);

1058

655

if(tcp_sd < 0){

1059

656

int e = errno;

1060

657

perror_plus("socket");

1069

666

1070

667

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

1071

668

if(af == AF_INET6){

1072

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

1073

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

669

to.in6.sin6_family = (sa_family_t)af;

670

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

1074

671

} else { /* IPv4 */

1075

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

1076

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

672

to.in.sin_family = (sa_family_t)af;

673

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

1077

674

}

1078

675

if(ret < 0 ){

1079

676

int e = errno;

1083

680

}

1084

681

if(ret == 0){

1085

682

int e = errno;

1086

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

683

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

1087

684

errno = e;

1088

685

goto mandos_end;

1089

686

}

1090

687

if(af == AF_INET6){

1091

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

1092

if(IN6_IS_ADDR_LINKLOCAL

1093

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

688

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

689

-Wconversion and

690

-Wunreachable-code */

691

692

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

693

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

694

-Wunreachable-code*/

1094

695

if(if_index == AVAHI_IF_UNSPEC){

1095

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

1096

" incomplete without a network interface\n");

696

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

697

" without a network interface\n");

1097

698

errno = EINVAL;

1098

699

goto mandos_end;

1099

700

}

1100

701

/* Set the network interface number as scope */

1101

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

702

to.in6.sin6_scope_id = (uint32_t)if_index;

1102

703

}

1103

704

} else {

1104

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

705

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

706

-Wconversion and

707

-Wunreachable-code */

1105

708

}

1106

709

1107

710

if(quit_now){

1115

718

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

1116

719

perror_plus("if_indextoname");

1117

720

} else {

1118

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

1119

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

721

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

722

ip, interface, port);

1120

723

}

1121

724

} else {

1122

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

1123

ip, (uintmax_t)port);

725

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

726

port);

1124

727

}

1125

728

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1126

729

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1127

if(af == AF_INET6){

1128

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

1129

sizeof(struct sockaddr_in6),

1130

addrstr, sizeof(addrstr), NULL, 0,

1131

NI_NUMERICHOST);

1132

} else {

1133

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

1134

sizeof(struct sockaddr_in),

1135

addrstr, sizeof(addrstr), NULL, 0,

1136

NI_NUMERICHOST);

1137

}

1138

if(ret == EAI_SYSTEM){

1139

perror_plus("getnameinfo");

1140

} else if(ret != 0) {

1141

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

1142

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

1143

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

1144

}

1145

}

1146

1147

if(quit_now){

1148

errno = EINTR;

1149

goto mandos_end;

1150

}

1151

1152

while(true){

1153

if(af == AF_INET6){

1154

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

1155

sizeof(struct sockaddr_in6));

1156

} else {

1157

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

1158

sizeof(struct sockaddr_in));

1159

}

1160

if(ret < 0){

1161

if(errno == ENETUNREACH

1162

and if_index != AVAHI_IF_UNSPEC

1163

and connect_to == NULL

1164

and not route_added and

1165

((af == AF_INET6 and not

1166

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1167

&to)->sin6_addr)))

1168

or (af == AF_INET and

1169

/* Not a a IPv4LL address */

1170

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

1171

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

1172

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

1173

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

1174

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

1175

connect to a Mandos server announced by Avahi on a server

1176

host with a global address. Work around this by retrying

1177

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

1178

1179

Avahi bug reference:

1180

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

1181

https://bugs.debian.org/587961

1182

*/

1183

if(debug){

1184

fprintf_plus(stderr, "Mandos server unreachable, trying"

1185

" direct route\n");

1186

}

1187

int e = errno;

1188

route_added = add_local_route(ip, if_index);

1189

if(route_added){

1190

continue;

1191

}

1192

errno = e;

1193

}

1194

if(errno != ECONNREFUSED or debug){

1195

int e = errno;

1196

perror_plus("connect");

1197

errno = e;

1198

}

1199

goto mandos_end;

1200

}

1201

1202

if(quit_now){

1203

errno = EINTR;

1204

goto mandos_end;

1205

}

1206

break;

730

const char *pcret;

731

if(af == AF_INET6){

732

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

733

sizeof(addrstr));

734

} else {

735

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

736

sizeof(addrstr));

737

}

738

if(pcret == NULL){

739

perror_plus("inet_ntop");

740

} else {

741

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

742

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

743

}

744

}

745

}

746

747

if(quit_now){

748

errno = EINTR;

749

goto mandos_end;

750

}

751

752

if(af == AF_INET6){

753

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

754

} else {

755

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

756

}

757

if(ret < 0){

758

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

759

int e = errno;

760

perror_plus("connect");

761

errno = e;

762

}

763

goto mandos_end;

764

}

765

766

if(quit_now){

767

errno = EINTR;

768

goto mandos_end;

1207

769

}

1208

770

1209

771

const char *out = mandos_protocol_version;

1211

773

while(true){

1212

774

size_t out_size = strlen(out);

1213

775

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

1214

out_size - written));

776

out_size - written));

1215

777

if(ret == -1){

1216

778

int e = errno;

1217

779

perror_plus("write");

1237

799

}

1238

800

1239

801

if(debug){

1240

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

802

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

1241

803

}

1242

804

1243

805

if(quit_now){

1245

807

goto mandos_end;

1246

808

}

1247

809

1248

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

1249

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

1250

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

1251

gnutls_transport_set_ptr(session,

1252

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

810

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

811

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1253

812

1254

813

if(quit_now){

1255

814

errno = EINTR;

1266

825

1267

826

if(ret != GNUTLS_E_SUCCESS){

1268

827

if(debug){

1269

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

828

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

1270

829

gnutls_perror(ret);

1271

830

}

1272

831

errno = EPROTO;

1276

835

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

1277

836

1278

837

if(debug){

1279

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1280

" %s\n", ip);

838

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

839

ip);

1281

840

}

1282

841

1283

842

while(true){

1288

847

}

1289

848

1290

849

buffer_capacity = incbuffer(&buffer, buffer_length,

1291

buffer_capacity);

850

buffer_capacity);

1292

851

if(buffer_capacity == 0){

1293

852

int e = errno;

1294

853

perror_plus("incbuffer");

1321

880

}

1322

881

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

1323

882

if(ret < 0){

1324

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

1325

"***\n");

883

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

1326

884

gnutls_perror(ret);

1327

885

errno = EPROTO;

1328

886

goto mandos_end;

1329

887

}

1330

888

break;

1331

889

default:

1332

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

1333

" encrypted session with Mandos server\n");

890

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

891

" encrypted session with Mandos server\n");

1334

892

gnutls_bye(session, GNUTLS_SHUT_RDWR);

1335

893

errno = EIO;

1336

894

goto mandos_end;

1341

899

}

1342

900

1343

901

if(debug){

1344

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

902

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

1345

903

}

1346

904

1347

905

if(quit_now){

1359

917

1360

918

if(buffer_length > 0){

1361

919

ssize_t decrypted_buffer_size;

1362

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1363

&decrypted_buffer, mc);

920

decrypted_buffer_size = pgp_packet_decrypt(buffer,

921

buffer_length,

922

&decrypted_buffer);

1364

923

if(decrypted_buffer_size >= 0){

1365

924

1366

925

written = 0;

1376

935

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

1377

936

int e = errno;

1378

937

if(debug){

1379

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

1380

strerror(errno));

938

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

939

strerror(errno));

1381

940

}

1382

941

errno = e;

1383

942

goto mandos_end;

1392

951

1393

952

mandos_end:

1394

953

{

1395

if(route_added){

1396

if(not delete_local_route(ip, if_index)){

1397

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

1398

" interface %d", ip, if_index);

1399

}

1400

}

1401

954

int e = errno;

1402

955

free(decrypted_buffer);

1403

956

free(buffer);

1420

973

return retval;

1421

974

}

1422

975

1423

__attribute__((nonnull))

1424

976

static void resolve_callback(AvahiSServiceResolver *r,

1425

977

AvahiIfIndex interface,

1426

978

AvahiProtocol proto,

1434

986

AVAHI_GCC_UNUSED AvahiStringList *txt,

1435

987

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1436

988

flags,

1437

void *mc){

1438

if(r == NULL){

1439

return;

1440

}

989

AVAHI_GCC_UNUSED void* userdata){

990

assert(r);

1441

991

1442

992

/* Called whenever a service has been resolved successfully or

1443

993

timed out */

1444

994

1445

995

if(quit_now){

1446

avahi_s_service_resolver_free(r);

1447

996

return;

1448

997

}

1449

998

1450

999

switch(event){

1451

1000

default:

1452

1001

case AVAHI_RESOLVER_FAILURE:

1453

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

1454

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

1455

domain,

1456

avahi_strerror(avahi_server_errno

1457

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

1002

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

1003

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

1004

avahi_strerror(avahi_server_errno(mc.server)));

1458

1005

break;

1459

1006

1460

1007

case AVAHI_RESOLVER_FOUND:

1462

1009

char ip[AVAHI_ADDRESS_STR_MAX];

1463

1010

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

1464

1011

if(debug){

1465

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

1466

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

1467

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

1012

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

1013

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

1014

ip, (intmax_t)interface, port);

1468

1015

}

1469

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

1470

interface,

1471

avahi_proto_to_af(proto),

1472

mc);

1016

int ret = start_mandos_communication(ip, port, interface,

1017

avahi_proto_to_af(proto));

1473

1018

if(ret == 0){

1474

avahi_simple_poll_quit(simple_poll);

1019

avahi_simple_poll_quit(mc.simple_poll);

1475

1020

} else {

1476

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

1477

avahi_proto_to_af(proto),

1478

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

1479

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

1480

" list\n", name);

1481

}

1021

ret = add_server(ip, port, interface,

1022

avahi_proto_to_af(proto));

1482

1023

}

1483

1024

}

1484

1025

}

1494

1035

const char *domain,

1495

1036

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1496

1037

flags,

1497

void *mc){

1498

if(b == NULL){

1499

return;

1500

}

1038

AVAHI_GCC_UNUSED void* userdata){

1039

assert(b);

1501

1040

1502

1041

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

1503

1042

is removed from the LAN */

1510

1049

default:

1511

1050

case AVAHI_BROWSER_FAILURE:

1512

1051

1513

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

1514

avahi_strerror(avahi_server_errno

1515

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

1516

avahi_simple_poll_quit(simple_poll);

1052

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

1053

avahi_strerror(avahi_server_errno(mc.server)));

1054

avahi_simple_poll_quit(mc.simple_poll);

1517

1055

return;

1518

1056

1519

1057

case AVAHI_BROWSER_NEW:

1522

1060

the callback function is called the Avahi server will free the

1523

1061

resolver for us. */

1524

1062

1525

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

1526

interface, protocol, name, type,

1527

domain, protocol, 0,

1528

resolve_callback, mc) == NULL)

1529

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

1530

" %s\n", name,

1531

avahi_strerror(avahi_server_errno

1532

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

1063

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

1064

name, type, domain, protocol, 0,

1065

resolve_callback, NULL) == NULL)

1066

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

1067

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

1533

1068

break;

1534

1069

1535

1070

case AVAHI_BROWSER_REMOVE:

1538

1073

case AVAHI_BROWSER_ALL_FOR_NOW:

1539

1074

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1540

1075

if(debug){

1541

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

1542

" searching...\n");

1076

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

1543

1077

}

1544

1078

break;

1545

1079

}

1554

1088

signal_received = sig;

1555

1089

int old_errno = errno;

1556

1090

/* set main loop to exit */

1557

if(simple_poll != NULL){

1558

avahi_simple_poll_quit(simple_poll);

1091

if(mc.simple_poll != NULL){

1092

avahi_simple_poll_quit(mc.simple_poll);

1559

1093

}

1560

1094

errno = old_errno;

1561

1095

}

1562

1096

1563

__attribute__((nonnull, warn_unused_result))

1564

1097

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

1565

1098

int ret;

1566

error_t ret_errno;

1567

1099

1568

1100

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

1569

1101

if(s < 0){

1570

ret_errno = errno;

1571

1102

perror_plus("socket");

1572

errno = ret_errno;

1573

1103

return false;

1574

1104

}

1575

1105

strcpy(ifr->ifr_name, ifname);

1576

1106

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1577

1107

if(ret == -1){

1578

1108

if(debug){

1579

ret_errno = errno;

1580

1109

perror_plus("ioctl SIOCGIFFLAGS");

1581

errno = ret_errno;

1582

1110

}

1583

1111

return false;

1584

1112

}

1585

1113

return true;

1586

1114

}

1587

1115

1588

__attribute__((nonnull, warn_unused_result))

1589

1116

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

1590

1117

1591

1118

/* Reject the loopback device */

1592

1119

if(ifr->ifr_flags & IFF_LOOPBACK){

1593

1120

if(debug){

1594

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

1595

ifname);

1121

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

1122

ifname);

1596

1123

}

1597

1124

return false;

1598

1125

}

1599

1126

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

1600

1127

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

1601

1128

if(debug){

1602

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

1603

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

1129

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

1130

ifname);

1604

1131

}

1605

1132

return true;

1606

1133

}

1607

1134

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

1608

1135

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

1609

1136

if(debug){

1610

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1611

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

1137

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

1138

ifname);

1612

1139

}

1613

1140

return false;

1614

1141

}

1615

1142

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

1616

1143

if(ifr->ifr_flags & IFF_NOARP){

1617

1144

if(debug){

1618

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

1619

ifname);

1145

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

1620

1146

}

1621

1147

return false;

1622

1148

}

1623

1149

1624

1150

/* Accept this device */

1625

1151

if(debug){

1626

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

1152

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

1627

1153

}

1628

1154

return true;

1629

1155

}

1633

1159

* corresponds to an acceptable network device.

1634

1160

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

1635

1161

*/

1636

__attribute__((nonnull, warn_unused_result))

1637

1162

int good_interface(const struct dirent *if_entry){

1163

int ret;

1638

1164

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

1639

1165

return 0;

1640

1166

}

1641

1642

1167

struct ifreq ifr;

1168

1643

1169

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

1644

if(debug){

1645

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

1646

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

1647

}

1648

1170

return 0;

1649

1171

}

1650

1172

1655

1177

}

1656

1178

1657

1179

/*

1658

* This function determines if a network interface is up.

1659

*/

1660

__attribute__((nonnull, warn_unused_result))

1661

bool interface_is_up(const char *interface){

1662

struct ifreq ifr;

1663

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

1664

if(debug){

1665

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

1666

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

1667

}

1668

return false;

1669

}

1670

1671

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

1672

}

1673

1674

/*

1675

* This function determines if a network interface is running

1676

*/

1677

__attribute__((nonnull, warn_unused_result))

1678

bool interface_is_running(const char *interface){

1679

struct ifreq ifr;

1680

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

1681

if(debug){

1682

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

1683

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

1684

}

1685

return false;

1686

}

1687

1688

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

1689

}

1690

1691

__attribute__((nonnull, pure, warn_unused_result))

1180

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

1181

* corresponds to an acceptable network device which is up.

1182

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

1183

*/

1184

int up_interface(const struct dirent *if_entry){

1185

ssize_t ssret;

1186

char *flagname = NULL;

1187

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

1188

return 0;

1189

}

1190

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

1191

if_entry->d_name);

1192

if(ret < 0){

1193

perror_plus("asprintf");

1194

return 0;

1195

}

1196

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

1197

if(flags_fd == -1){

1198

perror_plus("open");

1199

free(flagname);

1200

return 0;

1201

}

1202

free(flagname);

1203

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

1204

/* read line from flags_fd */

1205

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

1206

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

1207

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

1208

if(flagstring == NULL){

1209

perror_plus("malloc");

1210

close(flags_fd);

1211

return 0;

1212

}

1213

while(to_read > 0){

1214

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

1215

(size_t)to_read));

1216

if(ssret == -1){

1217

perror_plus("read");

1218

free(flagstring);

1219

close(flags_fd);

1220

return 0;

1221

}

1222

to_read -= ssret;

1223

if(ssret == 0){

1224

break;

1225

}

1226

}

1227

close(flags_fd);

1228

intmax_t tmpmax;

1229

char *tmp;

1230

errno = 0;

1231

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

1232

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

1233

and not (isspace(*tmp)))

1234

or tmpmax != (ifreq_flags)tmpmax){

1235

if(debug){

1236

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

1237

flagstring, if_entry->d_name);

1238

}

1239

free(flagstring);

1240

return 0;

1241

}

1242

free(flagstring);

1243

ifreq_flags flags = (ifreq_flags)tmpmax;

1244

/* Reject the loopback device */

1245

if(flags & IFF_LOOPBACK){

1246

if(debug){

1247

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

1248

if_entry->d_name);

1249

}

1250

return 0;

1251

}

1252

1253

/* Reject down interfaces */

1254

if(not (flags & IFF_UP)){

1255

return 0;

1256

}

1257

1258

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

1259

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

1260

if(debug){

1261

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

1262

if_entry->d_name);

1263

}

1264

return 1;

1265

}

1266

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

1267

if(not (flags & IFF_BROADCAST)){

1268

if(debug){

1269

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

1270

if_entry->d_name);

1271

}

1272

return 0;

1273

}

1274

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

1275

if(flags & IFF_NOARP){

1276

if(debug){

1277

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

1278

if_entry->d_name);

1279

}

1280

return 0;

1281

}

1282

/* Accept this device */

1283

if(debug){

1284

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

1285

if_entry->d_name);

1286

}

1287

return 1;

1288

}

1289

1692

1290

int notdotentries(const struct dirent *direntry){

1693

1291

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

1694

1292

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

1701

1299

}

1702

1300

1703

1301

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

1704

__attribute__((nonnull, warn_unused_result))

1705

1302

int runnable_hook(const struct dirent *direntry){

1706

1303

int ret;

1707

size_t sret;

1708

1304

struct stat st;

1709

1305

1710

1306

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

1712

1308

return 0;

1713

1309

}

1714

1310

1715

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

1716

"abcdefghijklmnopqrstuvwxyz"

1717

"0123456789"

1718

"_.-");

1719

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

1720

/* Contains non-allowed characters */

1721

if(debug){

1722

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

1723

direntry->d_name);

1724

}

1725

return 0;

1726

}

1727

1728

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

1311

/* Save pointer to last character */

1312

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

1313

1314

if(*end == '~'){

1315

/* Backup name~ */

1316

return 0;

1317

}

1318

1319

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

1320

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

1321

/* Temporary #name# */

1322

return 0;

1323

}

1324

1325

/* XXX more rules here */

1326

1327

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

1729

1328

if(ret == -1){

1730

1329

if(debug){

1731

perror_plus("Could not stat hook");

1330

perror_plus("Could not stat plugin");

1732

1331

}

1733

1332

return 0;

1734

1333

}

1735

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

1334

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

1736

1335

/* Not a regular file */

1737

if(debug){

1738

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

1739

direntry->d_name);

1740

}

1741

1336

return 0;

1742

1337

}

1743

1338

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

1744

1339

/* Not executable */

1745

if(debug){

1746

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

1747

direntry->d_name);

1748

}

1749

1340

return 0;

1750

1341

}

1751

if(debug){

1752

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

1753

direntry->d_name);

1754

}

1755

1342

return 1;

1756

1343

}

1757

1344

1758

__attribute__((nonnull, warn_unused_result))

1759

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1760

mandos_context *mc){

1345

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1761

1346

int ret;

1762

1347

struct timespec now;

1763

1348

struct timespec waited_time;

1764

1349

intmax_t block_time;

1765

1350

1766

1351

while(true){

1767

if(mc->current_server == NULL){

1768

if(debug){

1769

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

1770

" No timeout!\n");

1352

if(mc.current_server == NULL){

1353

if (debug){

1354

fprintf(stderr,

1355

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

1771

1356

}

1772

1357

ret = avahi_simple_poll_iterate(s, -1);

1773

1358

} else {

1774

if(debug){

1775

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

1776

" it, or wait\n");

1359

if (debug){

1360

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

1361

" or wait\n");

1777

1362

}

1778

1363

/* the current time */

1779

1364

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1784

1369

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

1785

1370

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

1786

1371

waited_time.tv_sec = (now.tv_sec

1787

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

1372

- mc.current_server->last_seen.tv_sec);

1788

1373

waited_time.tv_nsec = (now.tv_nsec

1789

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

1374

- mc.current_server->last_seen.tv_nsec);

1790

1375

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

1791

1376

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

1792

1377

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

1794

1379

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

1795

1380

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

1796

1381

1797

if(debug){

1798

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

1799

block_time);

1382

if (debug){

1383

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

1800

1384

}

1801

1385

1802

1386

if(block_time <= 0){

1803

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

1804

mc->current_server->port,

1805

mc->current_server->if_index,

1806

mc->current_server->af, mc);

1387

ret = start_mandos_communication(mc.current_server->ip,

1388

mc.current_server->port,

1389

mc.current_server->if_index,

1390

mc.current_server->af);

1807

1391

if(ret == 0){

1808

avahi_simple_poll_quit(s);

1392

avahi_simple_poll_quit(mc.simple_poll);

1809

1393

return 0;

1810

1394

}

1811

1395

ret = clock_gettime(CLOCK_MONOTONIC,

1812

&mc->current_server->last_seen);

1396

&mc.current_server->last_seen);

1813

1397

if(ret == -1){

1814

1398

perror_plus("clock_gettime");

1815

1399

return -1;

1816

1400

}

1817

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

1401

mc.current_server = mc.current_server->next;

1818

1402

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

1819

1403

servers, but don't block */

1820

1404

}

1822

1406

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

1823

1407

}

1824

1408

if(ret != 0){

1825

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

1409

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

1826

1410

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

1827

1411

}

1828

1412

}

1829

1413

}

1830

1414

}

1831

1415

1832

__attribute__((nonnull))

1833

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

1834

const float delay){

1835

struct dirent **direntries = NULL;

1836

if(hookdir_fd == -1){

1837

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1838

| O_CLOEXEC);

1839

if(hookdir_fd == -1){

1840

if(errno == ENOENT){

1841

if(debug){

1842

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

1843

" found\n", hookdir);

1844

}

1845

} else {

1846

perror_plus("open");

1847

}

1848

return;

1849

}

1850

}

1851

#ifdef __GLIBC__

1852

#if __GLIBC_PREREQ(2, 15)

1853

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

1854

runnable_hook, alphasort);

1855

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

1856

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

1857

alphasort);

1858

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

1859

#else /* not __GLIBC__ */

1860

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

1861

alphasort);

1862

#endif /* not __GLIBC__ */

1863

if(numhooks == -1){

1864

perror_plus("scandir");

1865

return;

1866

}

1867

struct dirent *direntry;

1868

int ret;

1869

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

1870

if(devnull == -1){

1871

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

1872

return;

1873

}

1874

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

1875

direntry = direntries[i];

1876

if(debug){

1877

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

1878

direntry->d_name);

1879

}

1880

pid_t hook_pid = fork();

1881

if(hook_pid == 0){

1882

/* Child */

1883

/* Raise privileges */

1884

errno = raise_privileges_permanently();

1885

if(errno != 0){

1886

perror_plus("Failed to raise privileges");

1887

_exit(EX_NOPERM);

1888

}

1889

/* Set group */

1890

errno = 0;

1891

ret = setgid(0);

1892

if(ret == -1){

1893

perror_plus("setgid");

1894

_exit(EX_NOPERM);

1895

}

1896

/* Reset supplementary groups */

1897

errno = 0;

1898

ret = setgroups(0, NULL);

1899

if(ret == -1){

1900

perror_plus("setgroups");

1901

_exit(EX_NOPERM);

1902

}

1903

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

1904

if(ret == -1){

1905

perror_plus("setenv");

1906

_exit(EX_OSERR);

1907

}

1908

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

1909

if(ret == -1){

1910

perror_plus("setenv");

1911

_exit(EX_OSERR);

1912

}

1913

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

1914

if(ret == -1){

1915

perror_plus("setenv");

1916

_exit(EX_OSERR);

1917

}

1918

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

1919

if(ret == -1){

1920

perror_plus("setenv");

1921

_exit(EX_OSERR);

1922

}

1923

char *delaystring;

1924

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

1925

if(ret == -1){

1926

perror_plus("asprintf");

1927

_exit(EX_OSERR);

1928

}

1929

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

1930

if(ret == -1){

1931

free(delaystring);

1932

perror_plus("setenv");

1933

_exit(EX_OSERR);

1934

}

1935

free(delaystring);

1936

if(connect_to != NULL){

1937

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

1938

if(ret == -1){

1939

perror_plus("setenv");

1940

_exit(EX_OSERR);

1941

}

1942

}

1943

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

1944

direntry->d_name,

1945

O_RDONLY));

1946

if(hook_fd == -1){

1947

perror_plus("openat");

1948

_exit(EXIT_FAILURE);

1949

}

1950

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

1951

perror_plus("close");

1952

_exit(EXIT_FAILURE);

1953

}

1954

ret = dup2(devnull, STDIN_FILENO);

1955

if(ret == -1){

1956

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

1957

_exit(EX_OSERR);

1958

}

1959

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

1960

if(ret == -1){

1961

perror_plus("close");

1962

_exit(EX_OSERR);

1963

}

1964

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1965

if(ret == -1){

1966

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

1967

_exit(EX_OSERR);

1968

}

1969

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

1970

environ) == -1){

1971

perror_plus("fexecve");

1972

_exit(EXIT_FAILURE);

1973

}

1974

} else {

1975

if(hook_pid == -1){

1976

perror_plus("fork");

1977

free(direntry);

1978

continue;

1979

}

1980

int status;

1981

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

1982

perror_plus("waitpid");

1983

free(direntry);

1984

continue;

1985

}

1986

if(WIFEXITED(status)){

1987

if(WEXITSTATUS(status) != 0){

1988

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

1989

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

1990

WEXITSTATUS(status));

1991

free(direntry);

1992

continue;

1993

}

1994

} else if(WIFSIGNALED(status)){

1995

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

1996

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

1997

WTERMSIG(status));

1998

free(direntry);

1999

continue;

2000

} else {

2001

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

2002

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

2003

free(direntry);

2004

continue;

2005

}

2006

}

2007

if(debug){

2008

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

2009

direntry->d_name);

2010

}

2011

free(direntry);

2012

}

2013

free(direntries);

2014

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

2015

perror_plus("close");

2016

} else {

2017

hookdir_fd = -1;

2018

}

2019

close(devnull);

2020

}

2021

2022

__attribute__((nonnull, warn_unused_result))

2023

error_t bring_up_interface(const char *const interface,

2024

const float delay){

2025

error_t old_errno = errno;

2026

int ret;

2027

struct ifreq network;

2028

unsigned int if_index = if_nametoindex(interface);

2029

if(if_index == 0){

2030

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

2031

errno = old_errno;

2032

return ENXIO;

2033

}

2034

2035

if(quit_now){

2036

errno = old_errno;

2037

return EINTR;

2038

}

2039

2040

if(not interface_is_up(interface)){

2041

error_t ret_errno = 0, ioctl_errno = 0;

2042

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

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 |= IFF_UP; /* set 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(quit_now){

2060

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

2061

if(ret == -1){

2062

perror_plus("close");

2063

}

2064

errno = old_errno;

2065

return EINTR;

2066

}

2067

2068

if(debug){

2069

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

2070

interface);

2071

}

2072

2073

/* Raise privileges */

2074

ret_errno = raise_privileges();

2075

if(ret_errno != 0){

2076

errno = ret_errno;

2077

perror_plus("Failed to raise privileges");

2078

}

2079

2080

#ifdef __linux__

2081

int ret_linux;

2082

bool restore_loglevel = false;

2083

if(ret_errno == 0){

2084

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2085

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

2086

ret_linux = klogctl(8, NULL, 5);

2087

if(ret_linux == -1){

2088

perror_plus("klogctl");

2089

} else {

2090

restore_loglevel = true;

2091

}

2092

}

2093

#endif /* __linux__ */

2094

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

2095

ioctl_errno = errno;

2096

#ifdef __linux__

2097

if(restore_loglevel){

2098

ret_linux = klogctl(7, NULL, 0);

2099

if(ret_linux == -1){

2100

perror_plus("klogctl");

2101

}

2102

}

2103

#endif /* __linux__ */

2104

2105

/* If raise_privileges() succeeded above */

2106

if(ret_errno == 0){

2107

/* Lower privileges */

2108

ret_errno = lower_privileges();

2109

if(ret_errno != 0){

2110

errno = ret_errno;

2111

perror_plus("Failed to lower privileges");

2112

}

2113

}

2114

2115

/* Close the socket */

2116

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

2117

if(ret == -1){

2118

perror_plus("close");

2119

}

2120

2121

if(ret_setflags == -1){

2122

errno = ioctl_errno;

2123

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2124

errno = old_errno;

2125

return ioctl_errno;

2126

}

2127

} else if(debug){

2128

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

2129

interface);

2130

}

2131

2132

/* Sleep checking until interface is running.

2133

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

2134

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

2135

if(interface_is_running(interface)){

2136

break;

2137

}

2138

struct timespec sleeptime = { .tv_nsec = 250000000 };

2139

ret = nanosleep(&sleeptime, NULL);

2140

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

2141

perror_plus("nanosleep");

2142

}

2143

}

2144

2145

errno = old_errno;

2146

return 0;

2147

}

2148

2149

__attribute__((nonnull, warn_unused_result))

2150

error_t take_down_interface(const char *const interface){

2151

error_t old_errno = errno;

2152

struct ifreq network;

2153

unsigned int if_index = if_nametoindex(interface);

2154

if(if_index == 0){

2155

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

2156

errno = old_errno;

2157

return ENXIO;

2158

}

2159

if(interface_is_up(interface)){

2160

error_t ret_errno = 0, ioctl_errno = 0;

2161

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

2162

ret_errno = errno;

2163

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

2164

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

2165

errno = old_errno;

2166

return ret_errno;

2167

}

2168

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

2169

2170

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

2171

if(sd == -1){

2172

ret_errno = errno;

2173

perror_plus("socket");

2174

errno = old_errno;

2175

return ret_errno;

2176

}

2177

2178

if(debug){

2179

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

2180

interface);

2181

}

2182

2183

/* Raise privileges */

2184

ret_errno = raise_privileges();

2185

if(ret_errno != 0){

2186

errno = ret_errno;

2187

perror_plus("Failed to raise privileges");

2188

}

2189

2190

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

2191

ioctl_errno = errno;

2192

2193

/* If raise_privileges() succeeded above */

2194

if(ret_errno == 0){

2195

/* Lower privileges */

2196

ret_errno = lower_privileges();

2197

if(ret_errno != 0){

2198

errno = ret_errno;

2199

perror_plus("Failed to lower privileges");

2200

}

2201

}

2202

2203

/* Close the socket */

2204

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

2205

if(ret == -1){

2206

perror_plus("close");

2207

}

2208

2209

if(ret_setflags == -1){

2210

errno = ioctl_errno;

2211

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2212

errno = old_errno;

2213

return ioctl_errno;

2214

}

2215

} else if(debug){

2216

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

2217

interface);

2218

}

2219

2220

errno = old_errno;

2221

return 0;

2222

}

2223

2224

1416

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

2225

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

2226

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

2227

"+CTYPE-OPENPGP:!RSA", .current_server = NULL,

2228

.interfaces = NULL, .interfaces_size = 0 };

2229

1417

AvahiSServiceBrowser *sb = NULL;

2230

error_t ret_errno;

1418

int error;

2231

1419

int ret;

2232

1420

intmax_t tmpmax;

2233

1421

char *tmp;

2234

1422

int exitcode = EXIT_SUCCESS;

2235

char *interfaces_to_take_down = NULL;

2236

size_t interfaces_to_take_down_size = 0;

2237

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

2238

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

2239

char *tempdir = NULL;

1423

const char *interface = "";

1424

struct ifreq network;

1425

int sd = -1;

1426

bool take_down_interface = false;

1427

uid_t uid;

1428

gid_t gid;

1429

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

1430

bool tempdir_created = false;

2240

1431

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2241

1432

const char *seckey = PATHDIR "/" SECKEY;

2242

1433

const char *pubkey = PATHDIR "/" PUBKEY;

2243

char *interfaces_hooks = NULL;

2244

1434

2245

1435

bool gnutls_initialized = false;

2246

1436

bool gpgme_initialized = false;

2308

1498

.group = 2 },

2309

1499

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

2310

1500

.arg = "SECONDS",

2311

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

2312

.group = 2 },

2313

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

2314

.arg = "DIR",

2315

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

1501

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

2316

1502

.group = 2 },

2317

1503

/*

2318

1504

* These reproduce what we would get without ARGP_NO_HELP

2337

1523

connect_to = arg;

2338

1524

break;

2339

1525

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

2340

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

2341

arg, (int)',');

2342

if(ret_errno != 0){

2343

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

2344

}

1526

interface = arg;

2345

1527

break;

2346

1528

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

2347

1529

seckey = arg;

2376

1558

argp_error(state, "Bad retry interval");

2377

1559

}

2378

1560

break;

2379

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

2380

hookdir = arg;

2381

break;

2382

1561

/*

2383

1562

* These reproduce what we would get without ARGP_NO_HELP

2384

1563

*/

2390

1569

argp_state_help(state, state->out_stream,

2391

1570

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2392

1571

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

2393

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

1572

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

2394

1573

exit(argp_err_exit_status);

2395

1574

break;

2396

1575

default:

2419

1598

goto end;

2420

1599

}

2421

1600

}

2422

1601

2423

1602

{

2424

1603

/* Work around Debian bug #633582:

2425

1604

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

2426

2427

/* Re-raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

} else {

2433

struct stat st;

2434

2435

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

2436

int seckey_fd = open(seckey, O_RDONLY);

2437

if(seckey_fd == -1){

2438

perror_plus("open");

2439

} else {

2440

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

2441

if(ret == -1){

2442

perror_plus("fstat");

2443

} else {

2444

if(S_ISREG(st.st_mode)

2445

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

2446

ret = fchown(seckey_fd, uid, gid);

2447

if(ret == -1){

2448

perror_plus("fchown");

2449

}

2450

}

2451

}

2452

TEMP_FAILURE_RETRY(close(seckey_fd));

2453

}

2454

}

2455

2456

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

2457

int pubkey_fd = open(pubkey, O_RDONLY);

2458

if(pubkey_fd == -1){

2459

perror_plus("open");

2460

} else {

2461

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

2462

if(ret == -1){

2463

perror_plus("fstat");

2464

} else {

2465

if(S_ISREG(st.st_mode)

2466

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

2467

ret = fchown(pubkey_fd, uid, gid);

2468

if(ret == -1){

2469

perror_plus("fchown");

2470

}

2471

}

2472

}

2473

TEMP_FAILURE_RETRY(close(pubkey_fd));

2474

}

2475

}

2476

2477

/* Lower privileges */

2478

ret_errno = lower_privileges();

2479

if(ret_errno != 0){

2480

errno = ret_errno;

2481

perror_plus("Failed to lower privileges");

2482

}

2483

}

2484

}

2485

2486

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

2487

{

2488

char *interface = NULL;

2489

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

2490

interface))){

2491

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

2492

and if_nametoindex(interface) == 0){

2493

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

2494

fprintf_plus(stderr, "Not using nonexisting interface"

2495

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

2496

}

2497

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

2498

interface = NULL;

2499

}

2500

}

2501

}

2502

2503

/* Run network hooks */

2504

{

2505

if(mc.interfaces != NULL){

2506

interfaces_hooks = malloc(mc.interfaces_size);

2507

if(interfaces_hooks == NULL){

2508

perror_plus("malloc");

1605

struct stat st;

1606

1607

/* Re-raise priviliges */

1608

errno = 0;

1609

ret = seteuid(0);

1610

if(ret == -1){

1611

perror_plus("seteuid");

1612

}

1613

1614

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

1615

int seckey_fd = open(seckey, O_RDONLY);

1616

if(seckey_fd == -1){

1617

perror_plus("open");

1618

} else {

1619

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

1620

if(ret == -1){

1621

perror_plus("fstat");

1622

} else {

1623

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

1624

ret = fchown(seckey_fd, uid, gid);

1625

if(ret == -1){

1626

perror_plus("fchown");

1627

}

1628

}

1629

}

1630

TEMP_FAILURE_RETRY(close(seckey_fd));

1631

}

1632

}

1633

1634

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

1635

int pubkey_fd = open(pubkey, O_RDONLY);

1636

if(pubkey_fd == -1){

1637

perror_plus("open");

1638

} else {

1639

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

1640

if(ret == -1){

1641

perror_plus("fstat");

1642

} else {

1643

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

1644

ret = fchown(pubkey_fd, uid, gid);

1645

if(ret == -1){

1646

perror_plus("fchown");

1647

}

1648

}

1649

}

1650

TEMP_FAILURE_RETRY(close(pubkey_fd));

1651

}

1652

}

1653

1654

/* Lower privileges */

1655

errno = 0;

1656

ret = seteuid(uid);

1657

if(ret == -1){

1658

perror_plus("seteuid");

1659

}

1660

}

1661

1662

/* Find network hooks and run them */

1663

{

1664

struct dirent **direntries;

1665

struct dirent *direntry;

1666

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

1667

alphasort);

1668

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

1669

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

1670

direntry = direntries[0];

1671

char *fullname = NULL;

1672

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

1673

direntry->d_name);

1674

if(ret < 0){

1675

perror_plus("asprintf");

1676

continue;

1677

}

1678

pid_t hook_pid = fork();

1679

if(hook_pid == 0){

1680

/* Child */

1681

dup2(devnull, STDIN_FILENO);

1682

close(devnull);

1683

dup2(STDERR_FILENO, STDOUT_FILENO);

1684

setenv("DEVICE", interface, 1);

1685

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

1686

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

1687

/* setenv( XXX more here */

1688

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

1689

perror_plus("execl");

1690

}

1691

free(fullname);

1692

if(quit_now){

2509

1693

goto end;

2510

1694

}

2511

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

2512

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

2513

1695

}

2514

run_network_hooks("start", interfaces_hooks != NULL ?

2515

interfaces_hooks : "", delay);

1696

close(devnull);

2516

1697

}

2517

1698

2518

1699

if(not debug){

2519

1700

avahi_set_log_function(empty_log);

2520

1701

}

2521

1702

1703

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

1704

struct dirent **direntries;

1705

ret = scandir(sys_class_net, &direntries, good_interface,

1706

alphasort);

1707

if(ret >= 1){

1708

/* Pick the first good interface */

1709

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

1710

if(debug){

1711

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

1712

}

1713

if(interface == NULL){

1714

perror_plus("malloc");

1715

free(direntries);

1716

exitcode = EXIT_FAILURE;

1717

goto end;

1718

}

1719

free(direntries);

1720

} else {

1721

free(direntries);

1722

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

1723

exitcode = EXIT_FAILURE;

1724

goto end;

1725

}

1726

}

1727

2522

1728

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

2523

1729

from the signal handler */

2524

1730

/* Initialize the pseudo-RNG for Avahi */

2525

1731

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

2526

simple_poll = avahi_simple_poll_new();

2527

if(simple_poll == NULL){

2528

fprintf_plus(stderr,

2529

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

1732

mc.simple_poll = avahi_simple_poll_new();

1733

if(mc.simple_poll == NULL){

1734

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

2530

1735

exitcode = EX_UNAVAILABLE;

2531

1736

goto end;

2532

1737

}

2594

1799

}

2595

1800

}

2596

1801

2597

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

2598

if(mc.interfaces == NULL){

2599

struct dirent **direntries = NULL;

2600

/* Look for any good interfaces */

2601

ret = scandir(sys_class_net, &direntries, good_interface,

2602

alphasort);

2603

if(ret >= 1){

2604

/* Add all found interfaces to interfaces list */

2605

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

2606

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

2607

direntries[i]->d_name);

2608

if(ret_errno != 0){

2609

errno = ret_errno;

2610

perror_plus("argz_add");

2611

free(direntries[i]);

2612

continue;

2613

}

2614

if(debug){

2615

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

2616

direntries[i]->d_name);

2617

}

2618

free(direntries[i]);

2619

}

2620

free(direntries);

1802

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

1803

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

1804

if_index = (AvahiIfIndex) if_nametoindex(interface);

1805

if(if_index == 0){

1806

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

1807

exitcode = EX_UNAVAILABLE;

1808

goto end;

1809

}

1810

1811

if(quit_now){

1812

goto end;

1813

}

1814

1815

/* Re-raise priviliges */

1816

errno = 0;

1817

ret = seteuid(0);

1818

if(ret == -1){

1819

perror_plus("seteuid");

1820

}

1821

1822

#ifdef __linux__

1823

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1824

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

1825

ret = klogctl(8, NULL, 5);

1826

bool restore_loglevel = true;

1827

if(ret == -1){

1828

restore_loglevel = false;

1829

perror_plus("klogctl");

1830

}

1831

#endif /* __linux__ */

1832

1833

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1834

if(sd < 0){

1835

perror_plus("socket");

1836

exitcode = EX_OSERR;

1837

#ifdef __linux__

1838

if(restore_loglevel){

1839

ret = klogctl(7, NULL, 0);

1840

if(ret == -1){

1841

perror_plus("klogctl");

1842

}

1843

}

1844

#endif /* __linux__ */

1845

/* Lower privileges */

1846

errno = 0;

1847

ret = seteuid(uid);

1848

if(ret == -1){

1849

perror_plus("seteuid");

1850

}

1851

goto end;

1852

}

1853

strcpy(network.ifr_name, interface);

1854

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

1855

if(ret == -1){

1856

perror_plus("ioctl SIOCGIFFLAGS");

1857

#ifdef __linux__

1858

if(restore_loglevel){

1859

ret = klogctl(7, NULL, 0);

1860

if(ret == -1){

1861

perror_plus("klogctl");

1862

}

1863

}

1864

#endif /* __linux__ */

1865

exitcode = EX_OSERR;

1866

/* Lower privileges */

1867

errno = 0;

1868

ret = seteuid(uid);

1869

if(ret == -1){

1870

perror_plus("seteuid");

1871

}

1872

goto end;

1873

}

1874

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

1875

network.ifr_flags |= IFF_UP;

1876

take_down_interface = true;

1877

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

1878

if(ret == -1){

1879

take_down_interface = false;

1880

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1881

exitcode = EX_OSERR;

1882

#ifdef __linux__

1883

if(restore_loglevel){

1884

ret = klogctl(7, NULL, 0);

1885

if(ret == -1){

1886

perror_plus("klogctl");

1887

}

1888

}

1889

#endif /* __linux__ */

1890

/* Lower privileges */

1891

errno = 0;

1892

ret = seteuid(uid);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

goto end;

1897

}

1898

}

1899

/* Sleep checking until interface is running.

1900

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

1901

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

1902

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

1903

if(ret == -1){

1904

perror_plus("ioctl SIOCGIFFLAGS");

1905

} else if(network.ifr_flags & IFF_RUNNING){

1906

break;

1907

}

1908

struct timespec sleeptime = { .tv_nsec = 250000000 };

1909

ret = nanosleep(&sleeptime, NULL);

1910

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

1911

perror_plus("nanosleep");

1912

}

1913

}

1914

if(not take_down_interface){

1915

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

1916

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

1917

if(ret == -1){

1918

perror_plus("close");

1919

}

1920

}

1921

#ifdef __linux__

1922

if(restore_loglevel){

1923

/* Restores kernel loglevel to default */

1924

ret = klogctl(7, NULL, 0);

1925

if(ret == -1){

1926

perror_plus("klogctl");

1927

}

1928

}

1929

#endif /* __linux__ */

1930

/* Lower privileges */

1931

errno = 0;

1932

if(take_down_interface){

1933

/* Lower privileges */

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

2621

1938

} else {

2622

if(ret == 0){

2623

free(direntries);

2624

}

2625

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

2626

exitcode = EXIT_FAILURE;

2627

goto end;

2628

}

2629

}

2630

2631

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

2632

{

2633

char *interface = NULL;

2634

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

2635

interface))){

2636

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

2637

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

2638

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

2639

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

2640

interface);

2641

interface = NULL;

2642

while((interface = argz_next(mc.interfaces,

2643

mc.interfaces_size, interface))){

2644

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

2645

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

2646

interface);

2647

interface = NULL;

2648

}

2649

}

2650

break;

2651

}

2652

bool interface_was_up = interface_is_up(interface);

2653

errno = bring_up_interface(interface, delay);

2654

if(not interface_was_up){

2655

if(errno != 0){

2656

perror_plus("Failed to bring up interface");

2657

} else {

2658

errno = argz_add(&interfaces_to_take_down,

2659

&interfaces_to_take_down_size,

2660

interface);

2661

if(errno != 0){

2662

perror_plus("argz_add");

2663

}

2664

}

2665

}

2666

}

2667

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

2668

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

2669

}

2670

}

2671

2672

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

2673

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

2674

if(debug){

2675

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

2676

mc.interfaces);

2677

}

2678

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

1939

/* Lower privileges permanently */

1940

ret = setuid(uid);

1941

if(ret == -1){

1942

perror_plus("setuid");

1943

}

1944

}

2679

1945

}

2680

1946

2681

1947

if(quit_now){

2682

1948

goto end;

2683

1949

}

2684

1950

2685

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

1951

ret = init_gnutls_global(pubkey, seckey);

2686

1952

if(ret == -1){

2687

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

1953

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

2688

1954

exitcode = EX_UNAVAILABLE;

2689

1955

goto end;

2690

1956

} else {

2695

1961

goto end;

2696

1962

}

2697

1963

2698

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

2699

tempdir = mkdtemp(run_tempdir);

2700

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

2701

if(debug){

2702

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

2703

run_tempdir, old_tempdir);

2704

}

2705

tempdir = mkdtemp(old_tempdir);

2706

}

2707

if(tempdir == NULL){

1964

if(mkdtemp(tempdir) == NULL){

2708

1965

perror_plus("mkdtemp");

2709

1966

goto end;

2710

1967

}

1968

tempdir_created = true;

2711

1969

2712

1970

if(quit_now){

2713

1971

goto end;

2714

1972

}

2715

1973

2716

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

2717

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

1974

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

1975

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

2718

1976

exitcode = EX_UNAVAILABLE;

2719

1977

goto end;

2720

1978

} else {

2729

1987

/* Connect directly, do not use Zeroconf */

2730

1988

/* (Mainly meant for debugging) */

2731

1989

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

2732

2733

1990

if(address == NULL){

2734

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

1991

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

2735

1992

exitcode = EX_USAGE;

2736

1993

goto end;

2737

1994

}

2740

1997

goto end;

2741

1998

}

2742

1999

2743

in_port_t port;

2000

uint16_t port;

2744

2001

errno = 0;

2745

2002

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

2746

2003

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

2747

or tmpmax != (in_port_t)tmpmax){

2748

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

2004

or tmpmax != (uint16_t)tmpmax){

2005

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

2749

2006

exitcode = EX_USAGE;

2750

2007

goto end;

2751

2008

}

2752

2009

2753

2010

if(quit_now){

2754

2011

goto end;

2755

2012

}

2756

2013

2757

port = (in_port_t)tmpmax;

2014

port = (uint16_t)tmpmax;

2758

2015

*address = '\0';

2759

2016

/* Colon in address indicates IPv6 */

2760

2017

int af;

2776

2033

}

2777

2034

2778

2035

while(not quit_now){

2779

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

2780

&mc);

2036

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

2781

2037

if(quit_now or ret == 0){

2782

2038

break;

2783

2039

}

2784

2040

if(debug){

2785

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

2786

(int)retry_interval);

2041

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

2042

(int)retry_interval);

2787

2043

}

2788

sleep((unsigned int)retry_interval);

2044

sleep((int)retry_interval);

2789

2045

}

2790

2046

2791

if(not quit_now){

2047

if (not quit_now){

2792

2048

exitcode = EXIT_SUCCESS;

2793

2049

}

2794

2050

2809

2065

config.publish_domain = 0;

2810

2066

2811

2067

/* Allocate a new server */

2812

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2813

&config, NULL, NULL, &ret_errno);

2068

mc.server = avahi_server_new(avahi_simple_poll_get

2069

(mc.simple_poll), &config, NULL,

2070

NULL, &error);

2814

2071

2815

2072

/* Free the Avahi configuration data */

2816

2073

avahi_server_config_free(&config);

2818

2075

2819

2076

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

2820

2077

if(mc.server == NULL){

2821

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

2822

avahi_strerror(ret_errno));

2078

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

2079

avahi_strerror(error));

2823

2080

exitcode = EX_UNAVAILABLE;

2824

2081

goto end;

2825

2082

}

2831

2088

/* Create the Avahi service browser */

2832

2089

sb = avahi_s_service_browser_new(mc.server, if_index,

2833

2090

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2834

NULL, 0, browse_callback,

2835

(void *)&mc);

2091

NULL, 0, browse_callback, NULL);

2836

2092

if(sb == NULL){

2837

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

2838

avahi_strerror(avahi_server_errno(mc.server)));

2093

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

2094

avahi_strerror(avahi_server_errno(mc.server)));

2839

2095

exitcode = EX_UNAVAILABLE;

2840

2096

goto end;

2841

2097

}

2847

2103

/* Run the main loop */

2848

2104

2849

2105

if(debug){

2850

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

2106

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

2851

2107

}

2852

2853

ret = avahi_loop_with_timeout(simple_poll,

2854

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

2108

2109

ret = avahi_loop_with_timeout(mc.simple_poll,

2110

(int)(retry_interval * 1000));

2855

2111

if(debug){

2856

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

2857

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

2112

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

2113

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

2858

2114

}

2859

2115

2860

2116

end:

2861

2117

2862

2118

if(debug){

2863

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

2119

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

2864

2120

}

2865

2121

2866

2122

/* Cleanup things */

2867

free(mc.interfaces);

2868

2869

2123

if(sb != NULL)

2870

2124

avahi_s_service_browser_free(sb);

2871

2125

2872

2126

if(mc.server != NULL)

2873

2127

avahi_server_free(mc.server);

2874

2128

2875

if(simple_poll != NULL)

2876

avahi_simple_poll_free(simple_poll);

2129

if(mc.simple_poll != NULL)

2130

avahi_simple_poll_free(mc.simple_poll);

2877

2131

2878

2132

if(gnutls_initialized){

2879

2133

gnutls_certificate_free_credentials(mc.cred);

2884

2138

if(gpgme_initialized){

2885

2139

gpgme_release(mc.ctx);

2886

2140

}

2887

2141

2888

2142

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

2889

2143

has seen */

2890

2144

if(mc.current_server != NULL){

2891

2145

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

2892

2146

while(mc.current_server != NULL){

2893

2147

server *next = mc.current_server->next;

2894

#ifdef __GNUC__

2895

#pragma GCC diagnostic push

2896

#pragma GCC diagnostic ignored "-Wcast-qual"

2897

#endif

2898

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

2899

#ifdef __GNUC__

2900

#pragma GCC diagnostic pop

2901

#endif

2902

2148

free(mc.current_server);

2903

2149

mc.current_server = next;

2904

2150

}

2905

2151

}

2906

2152

2907

/* Re-raise privileges */

2908

{

2909

ret_errno = raise_privileges();

2910

if(ret_errno != 0){

2911

errno = ret_errno;

2912

perror_plus("Failed to raise privileges");

2913

} else {

2914

2915

/* Run network hooks */

2916

run_network_hooks("stop", interfaces_hooks != NULL ?

2917

interfaces_hooks : "", delay);

2918

2919

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

2920

{

2921

char *interface = NULL;

2922

while((interface=argz_next(interfaces_to_take_down,

2923

interfaces_to_take_down_size,

2924

interface))){

2925

ret_errno = take_down_interface(interface);

2926

if(ret_errno != 0){

2927

errno = ret_errno;

2928

perror_plus("Failed to take down interface");

2929

}

2930

}

2931

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

2932

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

2933

" down\n");

2934

}

2935

}

2153

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

2154

2155

/* Take down the network interface */

2156

if(take_down_interface){

2157

/* Re-raise priviliges */

2158

errno = 0;

2159

ret = seteuid(0);

2160

if(ret == -1){

2161

perror_plus("seteuid");

2936

2162

}

2937

2938

ret_errno = lower_privileges_permanently();

2939

if(ret_errno != 0){

2940

errno = ret_errno;

2941

perror_plus("Failed to lower privileges permanently");

2163

if(geteuid() == 0){

2164

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

2165

if(ret == -1){

2166

perror_plus("ioctl SIOCGIFFLAGS");

2167

} else if(network.ifr_flags & IFF_UP) {

2168

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

2169

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

2170

if(ret == -1){

2171

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2172

}

2173

}

2174

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

2175

if(ret == -1){

2176

perror_plus("close");

2177

}

2178

/* Lower privileges permanently */

2179

errno = 0;

2180

ret = setuid(uid);

2181

if(ret == -1){

2182

perror_plus("setuid");

2183

}

2942

2184

}

2943

2185

}

2944

2186

2945

free(interfaces_to_take_down);

2946

free(interfaces_hooks);

2947

2948

2187

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

2949

if(tempdir != NULL){

2188

if(tempdir_created){

2950

2189

struct dirent **direntries = NULL;

2951

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

2952

| O_NOFOLLOW

2953

| O_DIRECTORY

2954

| O_PATH));

2955

if(tempdir_fd == -1){

2956

perror_plus("open");

2957

} else {

2958

#ifdef __GLIBC__

2959

#if __GLIBC_PREREQ(2, 15)

2960

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

2961

notdotentries, alphasort);

2962

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

2963

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

2964

alphasort);

2965

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

2966

#else /* not __GLIBC__ */

2967

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

2968

alphasort);

2969

#endif /* not __GLIBC__ */

2970

if(numentries >= 0){

2971

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

2972

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

2973

if(ret == -1){

2974

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

2975

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

2976

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

2977

}

2978

free(direntries[i]);

2979

}

2980

2981

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

2982

free(direntries);

2983

if(numentries == -1){

2984

perror_plus("scandir");

2985

}

2986

ret = rmdir(tempdir);

2987

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

2988

perror_plus("rmdir");

2989

}

2190

struct dirent *direntry = NULL;

2191

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

2192

alphasort);

2193

if (numentries > 0){

2194

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

2195

direntry = direntries[i];

2196

char *fullname = NULL;

2197

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

2198

direntry->d_name);

2199

if(ret < 0){

2200

perror_plus("asprintf");

2201

continue;

2202

}

2203

ret = remove(fullname);

2204

if(ret == -1){

2205

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

2206

strerror(errno));

2207

}

2208

free(fullname);

2990

2209

}

2991

TEMP_FAILURE_RETRY(close(tempdir_fd));

2210

}

2211

2212

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

2213

free(direntries);

2214

if (numentries == -1){

2215

perror_plus("scandir");

2216

}

2217

ret = rmdir(tempdir);

2218

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

2219

perror_plus("rmdir");

2992

2220

}

2993

2221

}

2994

2222