/mandos/trunk : revision 505.2.4

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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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13

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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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90

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

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108

init_gnutls_session(),

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109

GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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137

const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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/* Used for passing in values through the Avahi callback functions */

161

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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151

unsigned int dh_bits;

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153

const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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mandos_context mc = { .simple_poll = NULL, .server = NULL,

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.dh_bits = 1024, .priority = "SECURE256"

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":!CTYPE-X.509:+CTYPE-OPENPGP",

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

177

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int signal_received = 0;

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166

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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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170

program_invocation_short_name);

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errno = e;

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171

perror(print_text);

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172

}

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

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

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va_list ap;

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va_start (ap, format);

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177

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

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program_invocation_short_name));

195

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

178

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

179

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.

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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

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

222

__attribute__((nonnull, warn_unused_result))

223

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

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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;

226

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

227

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if(new_server == NULL){

228

206

perror_plus("malloc");

229

return false;

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return -1;

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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

213

if(new_server->ip == NULL){

236

214

perror_plus("strdup");

237

return false;

238

}

239

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

240

if(ret == -1){

241

perror_plus("clock_gettime");

242

return false;

215

return -1;

243

216

}

244

217

/* Special case of first server */

245

if(*current_server == NULL){

218

if (mc.current_server == NULL){

246

219

new_server->next = new_server;

247

220

new_server->prev = new_server;

248

*current_server = new_server;

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mc.current_server = new_server;

222

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

249

223

} else {

250

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

251

new_server->next = *current_server;

252

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

224

new_server->next = mc.current_server;

225

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

253

226

new_server->prev->next = new_server;

254

(*current_server)->prev = new_server;

255

}

256

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

}

234

return 0;

257

235

}

258

236

259

237

/*

260

238

* Initialize GPGME.

261

239

*/

262

__attribute__((nonnull, warn_unused_result))

263

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){

240

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

267

242

gpgme_error_t rc;

268

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gpgme_engine_info_t engine_info;

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245

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/*

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

272

248

*/

273

bool import_key(const char * const filename){

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bool import_key(const char *filename){

274

250

int ret;

275

251

int fd;

276

252

gpgme_data_t pgp_data;

283

259

284

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

285

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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;

289

265

}

290

266

291

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

267

rc = gpgme_op_import(mc.ctx, pgp_data);

292

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if(rc != GPG_ERR_NO_ERROR){

293

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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271

return false;

296

272

}

297

273

304

280

}

305

281

306

282

if(debug){

307

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

283

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

308

284

}

309

285

310

286

/* Init GPGME */

311

287

gpgme_check_version(NULL);

312

288

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

313

289

if(rc != GPG_ERR_NO_ERROR){

314

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

315

gpgme_strsource(rc), gpgme_strerror(rc));

290

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

291

gpgme_strsource(rc), gpgme_strerror(rc));

316

292

return false;

317

293

}

318

294

319

295

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

320

296

rc = gpgme_get_engine_info(&engine_info);

321

297

if(rc != GPG_ERR_NO_ERROR){

322

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

323

gpgme_strsource(rc), gpgme_strerror(rc));

298

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

299

gpgme_strsource(rc), gpgme_strerror(rc));

324

300

return false;

325

301

}

326

302

while(engine_info != NULL){

332

308

engine_info = engine_info->next;

333

309

}

334

310

if(engine_info == NULL){

335

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

336

tempdir);

311

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

337

312

return false;

338

313

}

339

314

340

315

/* Create new GPGME "context" */

341

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

316

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

342

317

if(rc != GPG_ERR_NO_ERROR){

343

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

344

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

345

gpgme_strerror(rc));

318

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

319

gpgme_strsource(rc), gpgme_strerror(rc));

346

320

return false;

347

321

}

348

322

357

331

* Decrypt OpenPGP data.

358

332

* Returns -1 on error

359

333

*/

360

__attribute__((nonnull, warn_unused_result))

361

334

static ssize_t pgp_packet_decrypt(const char *cryptotext,

362

335

size_t crypto_size,

363

char **plaintext,

364

mandos_context *mc){

336

char **plaintext){

365

337

gpgme_data_t dh_crypto, dh_plain;

366

338

gpgme_error_t rc;

367

339

ssize_t ret;

369

341

ssize_t plaintext_length = 0;

370

342

371

343

if(debug){

372

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

344

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

373

345

}

374

346

375

347

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

376

348

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

377

349

0);

378

350

if(rc != GPG_ERR_NO_ERROR){

379

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

380

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));

381

353

return -1;

382

354

}

383

355

384

356

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

385

357

rc = gpgme_data_new(&dh_plain);

386

358

if(rc != GPG_ERR_NO_ERROR){

387

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

388

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

389

gpgme_strsource(rc), gpgme_strerror(rc));

359

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

360

gpgme_strsource(rc), gpgme_strerror(rc));

390

361

gpgme_data_release(dh_crypto);

391

362

return -1;

392

363

}

393

364

394

365

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

395

366

data buffer */

396

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

367

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

397

368

if(rc != GPG_ERR_NO_ERROR){

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

400

371

plaintext_length = -1;

401

372

if(debug){

402

373

gpgme_decrypt_result_t result;

403

result = gpgme_op_decrypt_result(mc->ctx);

374

result = gpgme_op_decrypt_result(mc.ctx);

404

375

if(result == NULL){

405

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

376

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

406

377

} else {

407

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

408

result->unsupported_algorithm);

409

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

410

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);

411

382

if(result->file_name != NULL){

412

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

383

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

413

384

}

414

385

gpgme_recipient_t recipient;

415

386

recipient = result->recipients;

416

387

while(recipient != NULL){

417

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

418

gpgme_pubkey_algo_name

419

(recipient->pubkey_algo));

420

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

421

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

422

recipient->status == GPG_ERR_NO_SECKEY

423

? "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");

424

394

recipient = recipient->next;

425

395

}

426

396

}

429

399

}

430

400

431

401

if(debug){

432

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

402

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

433

403

}

434

404

435

405

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

442

412

*plaintext = NULL;

443

413

while(true){

444

414

plaintext_capacity = incbuffer(plaintext,

445

(size_t)plaintext_length,

446

plaintext_capacity);

415

(size_t)plaintext_length,

416

plaintext_capacity);

447

417

if(plaintext_capacity == 0){

448

perror_plus("incbuffer");

449

plaintext_length = -1;

450

goto decrypt_end;

418

perror_plus("incbuffer");

419

plaintext_length = -1;

420

goto decrypt_end;

451

421

}

452

422

453

423

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

466

436

}

467

437

468

438

if(debug){

469

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

439

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

470

440

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

471

441

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

472

442

}

483

453

return plaintext_length;

484

454

}

485

455

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

488

const char *ret = gnutls_strerror(value);

456

static const char * safer_gnutls_strerror(int value){

457

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

458

-Wunreachable-code */

489

459

if(ret == NULL)

490

460

ret = "(unknown)";

491

461

return ret;

492

462

}

493

463

494

464

/* GnuTLS log function callback */

495

__attribute__((nonnull))

496

465

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

497

466

const char* string){

498

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

467

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

499

468

}

500

469

501

__attribute__((nonnull, warn_unused_result))

502

470

static int init_gnutls_global(const char *pubkeyfilename,

503

const char *seckeyfilename,

504

mandos_context *mc){

471

const char *seckeyfilename){

505

472

int ret;

506

473

507

474

if(debug){

508

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

475

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

509

476

}

510

477

511

478

ret = gnutls_global_init();

512

479

if(ret != GNUTLS_E_SUCCESS){

513

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

514

safer_gnutls_strerror(ret));

480

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

481

safer_gnutls_strerror(ret));

515

482

return -1;

516

483

}

517

484

524

491

}

525

492

526

493

/* OpenPGP credentials */

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

494

ret = gnutls_certificate_allocate_credentials(&mc.cred);

528

495

if(ret != GNUTLS_E_SUCCESS){

529

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

530

safer_gnutls_strerror(ret));

496

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

497

safer_gnutls_strerror(ret));

531

498

gnutls_global_deinit();

532

499

return -1;

533

500

}

534

501

535

502

if(debug){

536

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

537

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

538

pubkeyfilename,

539

seckeyfilename);

503

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

504

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

505

seckeyfilename);

540

506

}

541

507

542

508

ret = gnutls_certificate_set_openpgp_key_file

543

(mc->cred, pubkeyfilename, seckeyfilename,

509

(mc.cred, pubkeyfilename, seckeyfilename,

544

510

GNUTLS_OPENPGP_FMT_BASE64);

545

511

if(ret != GNUTLS_E_SUCCESS){

546

fprintf_plus(stderr,

547

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

548

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

549

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

550

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));

551

517

goto globalfail;

552

518

}

553

519

554

520

/* GnuTLS server initialization */

555

ret = gnutls_dh_params_init(&mc->dh_params);

521

ret = gnutls_dh_params_init(&mc.dh_params);

556

522

if(ret != GNUTLS_E_SUCCESS){

557

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

558

" initialization: %s\n",

559

safer_gnutls_strerror(ret));

523

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

524

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

560

525

goto globalfail;

561

526

}

562

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

527

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

563

528

if(ret != GNUTLS_E_SUCCESS){

564

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

565

safer_gnutls_strerror(ret));

529

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

530

safer_gnutls_strerror(ret));

566

531

goto globalfail;

567

532

}

568

533

569

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

534

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

570

535

571

536

return 0;

572

537

573

538

globalfail:

574

539

575

gnutls_certificate_free_credentials(mc->cred);

540

gnutls_certificate_free_credentials(mc.cred);

576

541

gnutls_global_deinit();

577

gnutls_dh_params_deinit(mc->dh_params);

542

gnutls_dh_params_deinit(mc.dh_params);

578

543

return -1;

579

544

}

580

545

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

546

static int init_gnutls_session(gnutls_session_t *session){

584

547

int ret;

585

548

/* GnuTLS session creation */

586

549

do {

590

553

}

591

554

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

592

555

if(ret != GNUTLS_E_SUCCESS){

593

fprintf_plus(stderr,

594

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

595

safer_gnutls_strerror(ret));

556

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

557

safer_gnutls_strerror(ret));

596

558

}

597

559

598

560

{

599

561

const char *err;

600

562

do {

601

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

563

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

602

564

if(quit_now){

603

565

gnutls_deinit(*session);

604

566

return -1;

605

567

}

606

568

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

607

569

if(ret != GNUTLS_E_SUCCESS){

608

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

609

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

610

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));

611

573

gnutls_deinit(*session);

612

574

return -1;

613

575

}

615

577

616

578

do {

617

579

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

618

mc->cred);

580

mc.cred);

619

581

if(quit_now){

620

582

gnutls_deinit(*session);

621

583

return -1;

622

584

}

623

585

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

624

586

if(ret != GNUTLS_E_SUCCESS){

625

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

626

safer_gnutls_strerror(ret));

587

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

588

safer_gnutls_strerror(ret));

627

589

gnutls_deinit(*session);

628

590

return -1;

629

591

}

631

593

/* ignore client certificate if any. */

632

594

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

633

595

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

596

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

635

597

636

598

return 0;

637

599

}

641

603

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

642

604

643

605

/* Called when a Mandos server is found */

644

__attribute__((nonnull, warn_unused_result))

645

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

606

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

646

607

AvahiIfIndex if_index,

647

int af, mandos_context *mc){

608

int af){

648

609

int ret, tcp_sd = -1;

649

610

ssize_t sret;

650

struct sockaddr_storage to;

611

union {

612

struct sockaddr_in in;

613

struct sockaddr_in6 in6;

614

} to;

651

615

char *buffer = NULL;

652

616

char *decrypted_buffer = NULL;

653

617

size_t buffer_length = 0;

672

636

pf = PF_INET;

673

637

break;

674

638

default:

675

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

639

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

676

640

errno = EINVAL;

677

641

return -1;

678

642

}

679

643

680

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

681

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

682

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

683

bool match = false;

684

{

685

char *interface = NULL;

686

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

687

interface))){

688

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

689

match = true;

690

break;

691

}

692

}

693

}

694

if(not match){

695

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

696

connect to the server */

697

if(debug){

698

char interface[IF_NAMESIZE];

699

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

700

perror_plus("if_indextoname");

701

} else {

702

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

703

" \"%s\"\n",

704

if_indextoname((unsigned int)if_index,

705

interface));

706

}

707

}

708

return -1;

709

}

710

}

711

712

ret = init_gnutls_session(&session, mc);

644

ret = init_gnutls_session(&session);

713

645

if(ret != 0){

714

646

return -1;

715

647

}

716

648

717

649

if(debug){

718

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

719

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

650

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

651

"\n", ip, port);

720

652

}

721

653

722

654

tcp_sd = socket(pf, SOCK_STREAM, 0);

734

666

735

667

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

736

668

if(af == AF_INET6){

737

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

738

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);

739

671

} else { /* IPv4 */

740

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

741

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);

742

674

}

743

675

if(ret < 0 ){

744

676

int e = errno;

748

680

}

749

681

if(ret == 0){

750

682

int e = errno;

751

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

683

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

752

684

errno = e;

753

685

goto mandos_end;

754

686

}

755

687

if(af == AF_INET6){

756

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

757

if(IN6_IS_ADDR_LINKLOCAL

758

(&((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*/

759

695

if(if_index == AVAHI_IF_UNSPEC){

760

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

761

" incomplete without a network interface\n");

696

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

697

" without a network interface\n");

762

698

errno = EINVAL;

763

699

goto mandos_end;

764

700

}

765

701

/* Set the network interface number as scope */

766

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

702

to.in6.sin6_scope_id = (uint32_t)if_index;

767

703

}

768

704

} else {

769

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

705

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

706

-Wconversion and

707

-Wunreachable-code */

770

708

}

771

709

772

710

if(quit_now){

780

718

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

781

719

perror_plus("if_indextoname");

782

720

} else {

783

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

784

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

721

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

722

ip, interface, port);

785

723

}

786

724

} else {

787

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

788

ip, (uintmax_t)port);

725

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

726

port);

789

727

}

790

728

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

791

729

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

730

const char *pcret;

792

731

if(af == AF_INET6){

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

732

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

733

sizeof(addrstr));

797

734

} else {

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

735

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

736

sizeof(addrstr));

802

737

}

803

if(ret == EAI_SYSTEM){

804

perror_plus("getnameinfo");

805

} else if(ret != 0) {

806

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

807

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

808

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

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

}

809

744

}

810

745

}

811

746

815

750

}

816

751

817

752

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

753

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

820

754

} else {

821

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

822

sizeof(struct sockaddr_in));

755

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

823

756

}

824

757

if(ret < 0){

825

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

758

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

826

759

int e = errno;

827

760

perror_plus("connect");

828

761

errno = e;

840

773

while(true){

841

774

size_t out_size = strlen(out);

842

775

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

843

out_size - written));

776

out_size - written));

844

777

if(ret == -1){

845

778

int e = errno;

846

779

perror_plus("write");

866

799

}

867

800

868

801

if(debug){

869

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

802

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

870

803

}

871

804

872

805

if(quit_now){

874

807

goto mandos_end;

875

808

}

876

809

877

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

878

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

879

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

880

gnutls_transport_set_ptr(session,

881

(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);

882

812

883

813

if(quit_now){

884

814

errno = EINTR;

895

825

896

826

if(ret != GNUTLS_E_SUCCESS){

897

827

if(debug){

898

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

828

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

899

829

gnutls_perror(ret);

900

830

}

901

831

errno = EPROTO;

905

835

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

906

836

907

837

if(debug){

908

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

909

" %s\n", ip);

838

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

839

ip);

910

840

}

911

841

912

842

while(true){

917

847

}

918

848

919

849

buffer_capacity = incbuffer(&buffer, buffer_length,

920

buffer_capacity);

850

buffer_capacity);

921

851

if(buffer_capacity == 0){

922

852

int e = errno;

923

853

perror_plus("incbuffer");

950

880

}

951

881

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

952

882

if(ret < 0){

953

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

954

"***\n");

883

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

955

884

gnutls_perror(ret);

956

885

errno = EPROTO;

957

886

goto mandos_end;

958

887

}

959

888

break;

960

889

default:

961

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

962

" encrypted session with Mandos server\n");

890

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

891

" encrypted session with Mandos server\n");

963

892

gnutls_bye(session, GNUTLS_SHUT_RDWR);

964

893

errno = EIO;

965

894

goto mandos_end;

970

899

}

971

900

972

901

if(debug){

973

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

902

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

974

903

}

975

904

976

905

if(quit_now){

988

917

989

918

if(buffer_length > 0){

990

919

ssize_t decrypted_buffer_size;

991

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

992

&decrypted_buffer, mc);

920

decrypted_buffer_size = pgp_packet_decrypt(buffer,

921

buffer_length,

922

&decrypted_buffer);

993

923

if(decrypted_buffer_size >= 0){

994

924

995

925

written = 0;

1005

935

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

1006

936

int e = errno;

1007

937

if(debug){

1008

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

1009

strerror(errno));

938

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

939

strerror(errno));

1010

940

}

1011

941

errno = e;

1012

942

goto mandos_end;

1043

973

return retval;

1044

974

}

1045

975

1046

__attribute__((nonnull))

1047

976

static void resolve_callback(AvahiSServiceResolver *r,

1048

977

AvahiIfIndex interface,

1049

978

AvahiProtocol proto,

1057

986

AVAHI_GCC_UNUSED AvahiStringList *txt,

1058

987

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1059

988

flags,

1060

void *mc){

1061

if(r == NULL){

1062

return;

1063

}

989

AVAHI_GCC_UNUSED void* userdata){

990

assert(r);

1064

991

1065

992

/* Called whenever a service has been resolved successfully or

1066

993

timed out */

1072

999

switch(event){

1073

1000

default:

1074

1001

case AVAHI_RESOLVER_FAILURE:

1075

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

1076

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

1077

domain,

1078

avahi_strerror(avahi_server_errno

1079

(((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)));

1080

1005

break;

1081

1006

1082

1007

case AVAHI_RESOLVER_FOUND:

1084

1009

char ip[AVAHI_ADDRESS_STR_MAX];

1085

1010

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

1086

1011

if(debug){

1087

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

1088

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

1089

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);

1090

1015

}

1091

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

1092

interface,

1093

avahi_proto_to_af(proto),

1094

mc);

1016

int ret = start_mandos_communication(ip, port, interface,

1017

avahi_proto_to_af(proto));

1095

1018

if(ret == 0){

1096

avahi_simple_poll_quit(simple_poll);

1019

avahi_simple_poll_quit(mc.simple_poll);

1097

1020

} else {

1098

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

1099

avahi_proto_to_af(proto),

1100

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

1101

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

1102

" list\n", name);

1103

}

1021

ret = add_server(ip, port, interface,

1022

avahi_proto_to_af(proto));

1104

1023

}

1105

1024

}

1106

1025

}

1116

1035

const char *domain,

1117

1036

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1118

1037

flags,

1119

void *mc){

1120

if(b == NULL){

1121

return;

1122

}

1038

AVAHI_GCC_UNUSED void* userdata){

1039

assert(b);

1123

1040

1124

1041

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

1125

1042

is removed from the LAN */

1132

1049

default:

1133

1050

case AVAHI_BROWSER_FAILURE:

1134

1051

1135

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

1136

avahi_strerror(avahi_server_errno

1137

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

1138

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);

1139

1055

return;

1140

1056

1141

1057

case AVAHI_BROWSER_NEW:

1144

1060

the callback function is called the Avahi server will free the

1145

1061

resolver for us. */

1146

1062

1147

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

1148

interface, protocol, name, type,

1149

domain, protocol, 0,

1150

resolve_callback, mc) == NULL)

1151

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

1152

" %s\n", name,

1153

avahi_strerror(avahi_server_errno

1154

(((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)));

1155

1068

break;

1156

1069

1157

1070

case AVAHI_BROWSER_REMOVE:

1160

1073

case AVAHI_BROWSER_ALL_FOR_NOW:

1161

1074

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1162

1075

if(debug){

1163

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

1164

" searching...\n");

1076

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

1165

1077

}

1166

1078

break;

1167

1079

}

1176

1088

signal_received = sig;

1177

1089

int old_errno = errno;

1178

1090

/* set main loop to exit */

1179

if(simple_poll != NULL){

1180

avahi_simple_poll_quit(simple_poll);

1091

if(mc.simple_poll != NULL){

1092

avahi_simple_poll_quit(mc.simple_poll);

1181

1093

}

1182

1094

errno = old_errno;

1183

1095

}

1184

1096

1185

__attribute__((nonnull, warn_unused_result))

1186

1097

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

1187

1098

int ret;

1188

error_t ret_errno;

1189

1099

1190

1100

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

1191

1101

if(s < 0){

1192

ret_errno = errno;

1193

1102

perror_plus("socket");

1194

errno = ret_errno;

1195

1103

return false;

1196

1104

}

1197

1105

strcpy(ifr->ifr_name, ifname);

1198

1106

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1199

1107

if(ret == -1){

1200

1108

if(debug){

1201

ret_errno = errno;

1202

1109

perror_plus("ioctl SIOCGIFFLAGS");

1203

errno = ret_errno;

1204

1110

}

1205

1111

return false;

1206

1112

}

1207

1113

return true;

1208

1114

}

1209

1115

1210

__attribute__((nonnull, warn_unused_result))

1211

1116

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

1212

1117

1213

1118

/* Reject the loopback device */

1214

1119

if(ifr->ifr_flags & IFF_LOOPBACK){

1215

1120

if(debug){

1216

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

1217

ifname);

1121

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

1122

ifname);

1218

1123

}

1219

1124

return false;

1220

1125

}

1221

1126

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

1222

1127

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

1223

1128

if(debug){

1224

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

1225

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

1129

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

1130

ifname);

1226

1131

}

1227

1132

return true;

1228

1133

}

1229

1134

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

1230

1135

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

1231

1136

if(debug){

1232

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1233

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

1137

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

1138

ifname);

1234

1139

}

1235

1140

return false;

1236

1141

}

1237

1142

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

1238

1143

if(ifr->ifr_flags & IFF_NOARP){

1239

1144

if(debug){

1240

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

1241

ifname);

1145

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

1242

1146

}

1243

1147

return false;

1244

1148

}

1245

1149

1246

1150

/* Accept this device */

1247

1151

if(debug){

1248

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

1152

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

1249

1153

}

1250

1154

return true;

1251

1155

}

1255

1159

* corresponds to an acceptable network device.

1256

1160

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

1257

1161

*/

1258

__attribute__((nonnull, warn_unused_result))

1259

1162

int good_interface(const struct dirent *if_entry){

1163

int ret;

1260

1164

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

1261

1165

return 0;

1262

1166

}

1263

1264

1167

struct ifreq ifr;

1168

1265

1169

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

1266

if(debug){

1267

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

1268

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

1269

}

1270

1170

return 0;

1271

1171

}

1272

1172

1277

1177

}

1278

1178

1279

1179

/*

1280

* This function determines if a network interface is up.

1281

*/

1282

__attribute__((nonnull, warn_unused_result))

1283

bool interface_is_up(const char *interface){

1284

struct ifreq ifr;

1285

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

1286

if(debug){

1287

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

1288

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

1289

}

1290

return false;

1291

}

1292

1293

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

1294

}

1295

1296

/*

1297

* This function determines if a network interface is running

1298

*/

1299

__attribute__((nonnull, warn_unused_result))

1300

bool interface_is_running(const char *interface){

1301

struct ifreq ifr;

1302

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

1303

if(debug){

1304

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

1305

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

1306

}

1307

return false;

1308

}

1309

1310

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

1311

}

1312

1313

__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

1314

1290

int notdotentries(const struct dirent *direntry){

1315

1291

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

1316

1292

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

1323

1299

}

1324

1300

1325

1301

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

1326

__attribute__((nonnull, warn_unused_result))

1327

1302

int runnable_hook(const struct dirent *direntry){

1328

1303

int ret;

1329

size_t sret;

1330

1304

struct stat st;

1331

1305

1332

1306

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

1334

1308

return 0;

1335

1309

}

1336

1310

1337

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

1338

"abcdefghijklmnopqrstuvwxyz"

1339

"0123456789"

1340

"_.-");

1341

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

1342

/* Contains non-allowed characters */

1343

if(debug){

1344

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

1345

direntry->d_name);

1346

}

1347

return 0;

1348

}

1349

1350

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);

1351

1328

if(ret == -1){

1352

1329

if(debug){

1353

perror_plus("Could not stat hook");

1330

perror_plus("Could not stat plugin");

1354

1331

}

1355

1332

return 0;

1356

1333

}

1357

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

1334

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

1358

1335

/* Not a regular file */

1359

if(debug){

1360

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

1361

direntry->d_name);

1362

}

1363

1336

return 0;

1364

1337

}

1365

1338

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

1366

1339

/* Not executable */

1367

if(debug){

1368

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

1369

direntry->d_name);

1370

}

1371

1340

return 0;

1372

1341

}

1373

if(debug){

1374

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

1375

direntry->d_name);

1376

}

1377

1342

return 1;

1378

1343

}

1379

1344

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1345

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1383

1346

int ret;

1384

1347

struct timespec now;

1385

1348

struct timespec waited_time;

1386

1349

intmax_t block_time;

1387

1350

1388

1351

while(true){

1389

if(mc->current_server == NULL){

1390

if(debug){

1391

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

1392

" 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");

1393

1356

}

1394

1357

ret = avahi_simple_poll_iterate(s, -1);

1395

1358

} else {

1396

if(debug){

1397

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

1398

" it, or wait\n");

1359

if (debug){

1360

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

1361

" or wait\n");

1399

1362

}

1400

1363

/* the current time */

1401

1364

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1406

1369

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

1407

1370

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

1408

1371

waited_time.tv_sec = (now.tv_sec

1409

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

1372

- mc.current_server->last_seen.tv_sec);

1410

1373

waited_time.tv_nsec = (now.tv_nsec

1411

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

1374

- mc.current_server->last_seen.tv_nsec);

1412

1375

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

1413

1376

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

1414

1377

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

1416

1379

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

1417

1380

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

1418

1381

1419

if(debug){

1420

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

1421

block_time);

1382

if (debug){

1383

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

1422

1384

}

1423

1385

1424

1386

if(block_time <= 0){

1425

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

1426

mc->current_server->port,

1427

mc->current_server->if_index,

1428

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);

1429

1391

if(ret == 0){

1430

avahi_simple_poll_quit(s);

1392

avahi_simple_poll_quit(mc.simple_poll);

1431

1393

return 0;

1432

1394

}

1433

1395

ret = clock_gettime(CLOCK_MONOTONIC,

1434

&mc->current_server->last_seen);

1396

&mc.current_server->last_seen);

1435

1397

if(ret == -1){

1436

1398

perror_plus("clock_gettime");

1437

1399

return -1;

1438

1400

}

1439

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

1401

mc.current_server = mc.current_server->next;

1440

1402

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

1441

1403

servers, but don't block */

1442

1404

}

1444

1406

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

1445

1407

}

1446

1408

if(ret != 0){

1447

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

1409

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

1448

1410

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

1449

1411

}

1450

1412

}

1451

1413

}

1452

1414

}

1453

1415

1454

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

1455

__attribute__((warn_unused_result))

1456

error_t raise_privileges(void){

1457

error_t old_errno = errno;

1458

error_t ret_errno = 0;

1459

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

1460

ret_errno = errno;

1461

perror_plus("seteuid");

1462

}

1463

errno = old_errno;

1464

return ret_errno;

1465

}

1466

1467

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

1468

__attribute__((warn_unused_result))

1469

error_t raise_privileges_permanently(void){

1470

error_t old_errno = errno;

1471

error_t ret_errno = raise_privileges();

1472

if(ret_errno != 0){

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

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

1477

ret_errno = errno;

1478

perror_plus("seteuid");

1479

}

1480

errno = old_errno;

1481

return ret_errno;

1482

}

1483

1484

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

1485

__attribute__((warn_unused_result))

1486

error_t lower_privileges(void){

1487

error_t old_errno = errno;

1488

error_t ret_errno = 0;

1489

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

1490

ret_errno = errno;

1491

perror_plus("seteuid");

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

error_t lower_privileges_permanently(void){

1500

error_t old_errno = errno;

1501

error_t ret_errno = 0;

1502

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

1503

ret_errno = errno;

1504

perror_plus("setuid");

1505

}

1506

errno = old_errno;

1507

return ret_errno;

1508

}

1509

1510

__attribute__((nonnull))

1511

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

1512

const float delay){

1513

struct dirent **direntries;

1514

if(hookdir_fd == -1){

1515

hookdir_fd = open(hookdir, O_RDONLY);

1516

if(hookdir_fd == -1){

1517

if(errno == ENOENT){

1518

if(debug){

1519

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

1520

" found\n", hookdir);

1521

}

1522

} else {

1523

perror_plus("open");

1524

}

1525

return;

1526

}

1527

}

1528

#ifdef __GLIBC__

1529

#if __GLIBC_PREREQ(2, 15)

1530

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

1531

runnable_hook, alphasort);

1532

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

1533

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

1534

alphasort);

1535

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

1536

#else /* not __GLIBC__ */

1537

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

1538

alphasort);

1539

#endif /* not __GLIBC__ */

1540

if(numhooks == -1){

1541

perror_plus("scandir");

1542

return;

1543

}

1544

struct dirent *direntry;

1545

int ret;

1546

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

1547

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

1548

direntry = direntries[i];

1549

if(debug){

1550

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

1551

direntry->d_name);

1552

}

1553

pid_t hook_pid = fork();

1554

if(hook_pid == 0){

1555

/* Child */

1556

/* Raise privileges */

1557

if(raise_privileges_permanently() != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1590

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

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

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

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

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

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

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

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

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

1612

if(ret == -1){

1613

perror_plus("asprintf");

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1618

free(delaystring);

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

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

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

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

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

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

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

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

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

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

1653

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

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

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

1659

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

1660

WTERMSIG(status));

1661

continue;

1662

} else {

1663

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

1664

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

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

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

1670

direntry->d_name);

1671

}

1672

}

1673

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

1674

perror_plus("close");

1675

} else {

1676

hookdir_fd = -1;

1677

}

1678

close(devnull);

1679

}

1680

1681

__attribute__((nonnull, warn_unused_result))

1682

error_t bring_up_interface(const char *const interface,

1683

const float delay){

1684

error_t old_errno = errno;

1685

int ret;

1686

struct ifreq network;

1687

unsigned int if_index = if_nametoindex(interface);

1688

if(if_index == 0){

1689

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

1690

errno = old_errno;

1691

return ENXIO;

1692

}

1693

1694

if(quit_now){

1695

errno = old_errno;

1696

return EINTR;

1697

}

1698

1699

if(not interface_is_up(interface)){

1700

error_t ret_errno = 0, ioctl_errno = 0;

1701

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

1702

ret_errno = errno;

1703

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

1704

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

1705

errno = old_errno;

1706

return ret_errno;

1707

}

1708

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

1709

1710

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

1711

if(sd == -1){

1712

ret_errno = errno;

1713

perror_plus("socket");

1714

errno = old_errno;

1715

return ret_errno;

1716

}

1717

1718

if(quit_now){

1719

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

1720

if(ret == -1){

1721

perror_plus("close");

1722

}

1723

errno = old_errno;

1724

return EINTR;

1725

}

1726

1727

if(debug){

1728

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

1729

interface);

1730

}

1731

1732

/* Raise privileges */

1733

ret_errno = raise_privileges();

1734

if(ret_errno != 0){

1735

perror_plus("Failed to raise privileges");

1736

}

1737

1738

#ifdef __linux__

1739

int ret_linux;

1740

bool restore_loglevel = false;

1741

if(ret_errno == 0){

1742

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1743

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

1744

ret_linux = klogctl(8, NULL, 5);

1745

if(ret_linux == -1){

1746

perror_plus("klogctl");

1747

} else {

1748

restore_loglevel = true;

1749

}

1750

}

1751

#endif /* __linux__ */

1752

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

1753

ioctl_errno = errno;

1754

#ifdef __linux__

1755

if(restore_loglevel){

1756

ret_linux = klogctl(7, NULL, 0);

1757

if(ret_linux == -1){

1758

perror_plus("klogctl");

1759

}

1760

}

1761

#endif /* __linux__ */

1762

1763

/* If raise_privileges() succeeded above */

1764

if(ret_errno == 0){

1765

/* Lower privileges */

1766

ret_errno = lower_privileges();

1767

if(ret_errno != 0){

1768

errno = ret_errno;

1769

perror_plus("Failed to lower privileges");

1770

}

1771

}

1772

1773

/* Close the socket */

1774

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

1775

if(ret == -1){

1776

perror_plus("close");

1777

}

1778

1779

if(ret_setflags == -1){

1780

errno = ioctl_errno;

1781

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1782

errno = old_errno;

1783

return ioctl_errno;

1784

}

1785

} else if(debug){

1786

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

1787

interface);

1788

}

1789

1790

/* Sleep checking until interface is running.

1791

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

1792

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

1793

if(interface_is_running(interface)){

1794

break;

1795

}

1796

struct timespec sleeptime = { .tv_nsec = 250000000 };

1797

ret = nanosleep(&sleeptime, NULL);

1798

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

1799

perror_plus("nanosleep");

1800

}

1801

}

1802

1803

errno = old_errno;

1804

return 0;

1805

}

1806

1807

__attribute__((nonnull, warn_unused_result))

1808

error_t take_down_interface(const char *const interface){

1809

error_t old_errno = errno;

1810

struct ifreq network;

1811

unsigned int if_index = if_nametoindex(interface);

1812

if(if_index == 0){

1813

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

1814

errno = old_errno;

1815

return ENXIO;

1816

}

1817

if(interface_is_up(interface)){

1818

error_t ret_errno = 0, ioctl_errno = 0;

1819

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

1820

ret_errno = errno;

1821

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

1822

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

1823

errno = old_errno;

1824

return ret_errno;

1825

}

1826

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

1827

1828

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

1829

if(sd == -1){

1830

ret_errno = errno;

1831

perror_plus("socket");

1832

errno = old_errno;

1833

return ret_errno;

1834

}

1835

1836

if(debug){

1837

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

1838

interface);

1839

}

1840

1841

/* Raise privileges */

1842

ret_errno = raise_privileges();

1843

if(ret_errno != 0){

1844

perror_plus("Failed to raise privileges");

1845

}

1846

1847

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

1848

ioctl_errno = errno;

1849

1850

/* If raise_privileges() succeeded above */

1851

if(ret_errno == 0){

1852

/* Lower privileges */

1853

ret_errno = lower_privileges();

1854

if(ret_errno != 0){

1855

errno = ret_errno;

1856

perror_plus("Failed to lower privileges");

1857

}

1858

}

1859

1860

/* Close the socket */

1861

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

1862

if(ret == -1){

1863

perror_plus("close");

1864

}

1865

1866

if(ret_setflags == -1){

1867

errno = ioctl_errno;

1868

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1869

errno = old_errno;

1870

return ioctl_errno;

1871

}

1872

} else if(debug){

1873

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

1874

interface);

1875

}

1876

1877

errno = old_errno;

1878

return 0;

1879

}

1880

1881

1416

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

1882

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

1883

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

1884

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

1885

.interfaces = NULL, .interfaces_size = 0 };

1886

1417

AvahiSServiceBrowser *sb = NULL;

1887

error_t ret_errno;

1418

int error;

1888

1419

int ret;

1889

1420

intmax_t tmpmax;

1890

1421

char *tmp;

1891

1422

int exitcode = EXIT_SUCCESS;

1892

char *interfaces_to_take_down = NULL;

1893

size_t interfaces_to_take_down_size = 0;

1894

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

1895

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

1896

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;

1897

1431

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1898

1432

const char *seckey = PATHDIR "/" SECKEY;

1899

1433

const char *pubkey = PATHDIR "/" PUBKEY;

1900

char *interfaces_hooks = NULL;

1901

1434

1902

1435

bool gnutls_initialized = false;

1903

1436

bool gpgme_initialized = false;

1965

1498

.group = 2 },

1966

1499

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

1967

1500

.arg = "SECONDS",

1968

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

1969

.group = 2 },

1970

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

1971

.arg = "DIR",

1972

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

1501

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

1973

1502

.group = 2 },

1974

1503

/*

1975

1504

* These reproduce what we would get without ARGP_NO_HELP

1994

1523

connect_to = arg;

1995

1524

break;

1996

1525

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

1997

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

1998

arg, (int)',');

1999

if(ret_errno != 0){

2000

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

2001

}

1526

interface = arg;

2002

1527

break;

2003

1528

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

2004

1529

seckey = arg;

2033

1558

argp_error(state, "Bad retry interval");

2034

1559

}

2035

1560

break;

2036

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

2037

hookdir = arg;

2038

break;

2039

1561

/*

2040

1562

* These reproduce what we would get without ARGP_NO_HELP

2041

1563

*/

2047

1569

argp_state_help(state, state->out_stream,

2048

1570

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2049

1571

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

2050

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

1572

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

2051

1573

exit(argp_err_exit_status);

2052

1574

break;

2053

1575

default:

2080

1602

{

2081

1603

/* Work around Debian bug #633582:

2082

1604

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

2083

2084

/* Re-raise privileges */

2085

ret_errno = raise_privileges();

2086

if(ret_errno != 0){

2087

errno = ret_errno;

2088

perror_plus("Failed to raise privileges");

2089

} else {

2090

struct stat st;

2091

2092

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

2093

int seckey_fd = open(seckey, O_RDONLY);

2094

if(seckey_fd == -1){

2095

perror_plus("open");

2096

} else {

2097

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

2098

if(ret == -1){

2099

perror_plus("fstat");

2100

} else {

2101

if(S_ISREG(st.st_mode)

2102

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

2103

ret = fchown(seckey_fd, uid, gid);

2104

if(ret == -1){

2105

perror_plus("fchown");

2106

}

2107

}

2108

}

2109

TEMP_FAILURE_RETRY(close(seckey_fd));

2110

}

2111

}

2112

2113

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

2114

int pubkey_fd = open(pubkey, O_RDONLY);

2115

if(pubkey_fd == -1){

2116

perror_plus("open");

2117

} else {

2118

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

2119

if(ret == -1){

2120

perror_plus("fstat");

2121

} else {

2122

if(S_ISREG(st.st_mode)

2123

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

2124

ret = fchown(pubkey_fd, uid, gid);

2125

if(ret == -1){

2126

perror_plus("fchown");

2127

}

2128

}

2129

}

2130

TEMP_FAILURE_RETRY(close(pubkey_fd));

2131

}

2132

}

2133

2134

/* Lower privileges */

2135

ret_errno = lower_privileges();

2136

if(ret_errno != 0){

2137

errno = ret_errno;

2138

perror_plus("Failed to lower privileges");

2139

}

2140

}

2141

}

2142

2143

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

2144

{

2145

char *interface = NULL;

2146

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

2147

interface))){

2148

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

2149

and if_nametoindex(interface) == 0){

2150

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

2151

fprintf_plus(stderr, "Not using nonexisting interface"

2152

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

2153

}

2154

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

2155

interface = NULL;

2156

}

2157

}

2158

}

2159

2160

/* Run network hooks */

2161

{

2162

if(mc.interfaces != NULL){

2163

interfaces_hooks = malloc(mc.interfaces_size);

2164

if(interfaces_hooks == NULL){

2165

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){

2166

1693

goto end;

2167

1694

}

2168

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

2169

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

2170

1695

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

1696

close(devnull);

2173

1697

}

2174

1698

2175

1699

if(not debug){

2176

1700

avahi_set_log_function(empty_log);

2177

1701

}

2178

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

2179

1728

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

2180

1729

from the signal handler */

2181

1730

/* Initialize the pseudo-RNG for Avahi */

2182

1731

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

2183

simple_poll = avahi_simple_poll_new();

2184

if(simple_poll == NULL){

2185

fprintf_plus(stderr,

2186

"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");

2187

1735

exitcode = EX_UNAVAILABLE;

2188

1736

goto end;

2189

1737

}

2251

1799

}

2252

1800

}

2253

1801

2254

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

2255

if(mc.interfaces == NULL){

2256

struct dirent **direntries = NULL;

2257

/* Look for any good interfaces */

2258

ret = scandir(sys_class_net, &direntries, good_interface,

2259

alphasort);

2260

if(ret >= 1){

2261

/* Add all found interfaces to interfaces list */

2262

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

2263

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

2264

direntries[i]->d_name);

2265

if(ret_errno != 0){

2266

errno = ret_errno;

2267

perror_plus("argz_add");

2268

continue;

2269

}

2270

if(debug){

2271

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

2272

direntries[i]->d_name);

2273

}

2274

}

2275

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

}

2276

1938

} else {

2277

free(direntries);

2278

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

2279

exitcode = EXIT_FAILURE;

2280

goto end;

2281

}

2282

}

2283

2284

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

2285

{

2286

char *interface = NULL;

2287

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

2288

interface))){

2289

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

2290

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

2291

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

2292

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

2293

interface);

2294

interface = NULL;

2295

while((interface = argz_next(mc.interfaces,

2296

mc.interfaces_size, interface))){

2297

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

2298

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

2299

interface);

2300

interface = NULL;

2301

}

2302

}

2303

break;

2304

}

2305

bool interface_was_up = interface_is_up(interface);

2306

errno = bring_up_interface(interface, delay);

2307

if(not interface_was_up){

2308

if(errno != 0){

2309

perror_plus("Failed to bring up interface");

2310

} else {

2311

errno = argz_add(&interfaces_to_take_down,

2312

&interfaces_to_take_down_size,

2313

interface);

2314

if(errno != 0){

2315

perror_plus("argz_add");

2316

}

2317

}

2318

}

2319

}

2320

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

2321

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

2322

}

2323

}

2324

2325

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

2326

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

2327

if(debug){

2328

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

2329

mc.interfaces);

2330

}

2331

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

}

2332

1945

}

2333

1946

2334

1947

if(quit_now){

2335

1948

goto end;

2336

1949

}

2337

1950

2338

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

1951

ret = init_gnutls_global(pubkey, seckey);

2339

1952

if(ret == -1){

2340

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

1953

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

2341

1954

exitcode = EX_UNAVAILABLE;

2342

1955

goto end;

2343

1956

} else {

2348

1961

goto end;

2349

1962

}

2350

1963

2351

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

2352

tempdir = mkdtemp(run_tempdir);

2353

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

2354

if(debug){

2355

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

2356

run_tempdir, old_tempdir);

2357

}

2358

tempdir = mkdtemp(old_tempdir);

2359

}

2360

if(tempdir == NULL){

1964

if(mkdtemp(tempdir) == NULL){

2361

1965

perror_plus("mkdtemp");

2362

1966

goto end;

2363

1967

}

1968

tempdir_created = true;

2364

1969

2365

1970

if(quit_now){

2366

1971

goto end;

2367

1972

}

2368

1973

2369

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

2370

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

1974

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

1975

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

2371

1976

exitcode = EX_UNAVAILABLE;

2372

1977

goto end;

2373

1978

} else {

2382

1987

/* Connect directly, do not use Zeroconf */

2383

1988

/* (Mainly meant for debugging) */

2384

1989

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

2385

2386

1990

if(address == NULL){

2387

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

1991

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

2388

1992

exitcode = EX_USAGE;

2389

1993

goto end;

2390

1994

}

2393

1997

goto end;

2394

1998

}

2395

1999

2396

in_port_t port;

2000

uint16_t port;

2397

2001

errno = 0;

2398

2002

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

2399

2003

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

2400

or tmpmax != (in_port_t)tmpmax){

2401

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

2004

or tmpmax != (uint16_t)tmpmax){

2005

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

2402

2006

exitcode = EX_USAGE;

2403

2007

goto end;

2404

2008

}

2405

2009

2406

2010

if(quit_now){

2407

2011

goto end;

2408

2012

}

2409

2013

2410

port = (in_port_t)tmpmax;

2014

port = (uint16_t)tmpmax;

2411

2015

*address = '\0';

2412

2016

/* Colon in address indicates IPv6 */

2413

2017

int af;

2429

2033

}

2430

2034

2431

2035

while(not quit_now){

2432

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

2433

&mc);

2036

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

2434

2037

if(quit_now or ret == 0){

2435

2038

break;

2436

2039

}

2437

2040

if(debug){

2438

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

2439

(int)retry_interval);

2041

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

2042

(int)retry_interval);

2440

2043

}

2441

sleep((unsigned int)retry_interval);

2044

sleep((int)retry_interval);

2442

2045

}

2443

2046

2444

if(not quit_now){

2047

if (not quit_now){

2445

2048

exitcode = EXIT_SUCCESS;

2446

2049

}

2447

2050

2462

2065

config.publish_domain = 0;

2463

2066

2464

2067

/* Allocate a new server */

2465

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2466

&config, NULL, NULL, &ret_errno);

2068

mc.server = avahi_server_new(avahi_simple_poll_get

2069

(mc.simple_poll), &config, NULL,

2070

NULL, &error);

2467

2071

2468

2072

/* Free the Avahi configuration data */

2469

2073

avahi_server_config_free(&config);

2471

2075

2472

2076

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

2473

2077

if(mc.server == NULL){

2474

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

2475

avahi_strerror(ret_errno));

2078

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

2079

avahi_strerror(error));

2476

2080

exitcode = EX_UNAVAILABLE;

2477

2081

goto end;

2478

2082

}

2484

2088

/* Create the Avahi service browser */

2485

2089

sb = avahi_s_service_browser_new(mc.server, if_index,

2486

2090

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2487

NULL, 0, browse_callback,

2488

(void *)&mc);

2091

NULL, 0, browse_callback, NULL);

2489

2092

if(sb == NULL){

2490

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

2491

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)));

2492

2095

exitcode = EX_UNAVAILABLE;

2493

2096

goto end;

2494

2097

}

2500

2103

/* Run the main loop */

2501

2104

2502

2105

if(debug){

2503

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

2106

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

2504

2107

}

2505

2506

ret = avahi_loop_with_timeout(simple_poll,

2507

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

2108

2109

ret = avahi_loop_with_timeout(mc.simple_poll,

2110

(int)(retry_interval * 1000));

2508

2111

if(debug){

2509

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

2510

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

2112

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

2113

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

2511

2114

}

2512

2115

2513

2116

end:

2514

2117

2515

2118

if(debug){

2516

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

2119

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

2517

2120

}

2518

2121

2519

2122

/* Cleanup things */

2520

free(mc.interfaces);

2521

2522

2123

if(sb != NULL)

2523

2124

avahi_s_service_browser_free(sb);

2524

2125

2525

2126

if(mc.server != NULL)

2526

2127

avahi_server_free(mc.server);

2527

2128

2528

if(simple_poll != NULL)

2529

avahi_simple_poll_free(simple_poll);

2129

if(mc.simple_poll != NULL)

2130

avahi_simple_poll_free(mc.simple_poll);

2530

2131

2531

2132

if(gnutls_initialized){

2532

2133

gnutls_certificate_free_credentials(mc.cred);

2537

2138

if(gpgme_initialized){

2538

2139

gpgme_release(mc.ctx);

2539

2140

}

2540

2141

2541

2142

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

2542

2143

has seen */

2543

2144

if(mc.current_server != NULL){

2549

2150

}

2550

2151

}

2551

2152

2552

/* Re-raise privileges */

2553

{

2554

ret_errno = raise_privileges();

2555

if(ret_errno != 0){

2556

perror_plus("Failed to raise privileges");

2557

} else {

2558

2559

/* Run network hooks */

2560

run_network_hooks("stop", interfaces_hooks != NULL ?

2561

interfaces_hooks : "", delay);

2562

2563

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

2564

{

2565

char *interface = NULL;

2566

while((interface=argz_next(interfaces_to_take_down,

2567

interfaces_to_take_down_size,

2568

interface))){

2569

ret_errno = take_down_interface(interface);

2570

if(ret_errno != 0){

2571

errno = ret_errno;

2572

perror_plus("Failed to take down interface");

2573

}

2574

}

2575

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

2576

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

2577

" down\n");

2578

}

2579

}

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");

2580

2162

}

2581

2582

ret_errno = lower_privileges_permanently();

2583

if(ret_errno != 0){

2584

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

}

2585

2184

}

2586

2185

}

2587

2186

2588

free(interfaces_to_take_down);

2589

free(interfaces_hooks);

2590

2591

2187

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

2592

if(tempdir != NULL){

2188

if(tempdir_created){

2593

2189

struct dirent **direntries = NULL;

2594

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

2595

O_NOFOLLOW));

2596

if(tempdir_fd == -1){

2597

perror_plus("open");

2598

} else {

2599

#ifdef __GLIBC__

2600

#if __GLIBC_PREREQ(2, 15)

2601

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

2602

notdotentries, alphasort);

2603

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

2604

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

2605

alphasort);

2606

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

2607

#else /* not __GLIBC__ */

2608

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

2609

alphasort);

2610

#endif /* not __GLIBC__ */

2611

if(numentries > 0){

2612

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

2613

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

2614

if(ret == -1){

2615

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

2616

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

2617

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

2618

}

2619

}

2620

2621

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

2622

free(direntries);

2623

if(numentries == -1){

2624

perror_plus("scandir");

2625

}

2626

ret = rmdir(tempdir);

2627

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

2628

perror_plus("rmdir");

2629

}

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);

2630

2209

}

2631

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");

2632

2220

}

2633

2221

}

2634

2222