/mandos/trunk : revision 505.2.3

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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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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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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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140

int af;

155

141

struct timespec last_seen;

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160

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

161

147

typedef struct {

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AvahiSimplePoll *simple_poll;

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149

AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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151

unsigned int dh_bits;

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153

const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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163

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164

sig_atomic_t quit_now = 0;

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165

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;

182

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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193

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

194

program_invocation_short_name));

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

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}

197

198

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/*

199

175

* Make additional room in "buffer" for at least BUFFER_SIZE more

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

201

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* "buffer_length" is how much is already used.

202

178

*/

203

__attribute__((nonnull, warn_unused_result))

204

179

size_t incbuffer(char **buffer, size_t buffer_length,

205

size_t buffer_capacity){

180

size_t buffer_capacity){

206

181

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

182

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

183

if(buffer == NULL){

213

184

return 0;

214

185

}

215

*buffer = new_buf;

216

186

buffer_capacity += BUFFER_SIZE;

217

187

}

218

188

return buffer_capacity;

219

189

}

220

190

221

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

222

__attribute__((nonnull, warn_unused_result))

223

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

224

int af, server **current_server){

192

int add_server(const char *ip, uint16_t port,

193

AvahiIfIndex if_index,

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int af){

225

195

int ret;

226

196

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

227

197

if(new_server == NULL){

228

198

perror_plus("malloc");

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return false;

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return -1;

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}

231

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

235

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if(new_server->ip == NULL){

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206

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;

207

return -1;

243

208

}

244

209

/* Special case of first server */

245

if(*current_server == NULL){

210

if (mc.current_server == NULL){

246

211

new_server->next = new_server;

247

212

new_server->prev = new_server;

248

*current_server = new_server;

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mc.current_server = new_server;

214

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

249

215

} else {

250

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

251

new_server->next = *current_server;

252

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

216

new_server->next = mc.current_server;

217

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

253

218

new_server->prev->next = new_server;

254

(*current_server)->prev = new_server;

255

}

256

return true;

219

mc.current_server->prev = new_server;

220

}

221

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

222

if(ret == -1){

223

perror_plus("clock_gettime");

224

return -1;

225

}

226

return 0;

257

227

}

258

228

259

229

/*

260

230

* Initialize GPGME.

261

231

*/

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,

266

mandos_context *mc){

232

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

267

234

gpgme_error_t rc;

268

235

gpgme_engine_info_t engine_info;

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236

237

270

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/*

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

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240

*/

273

bool import_key(const char * const filename){

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bool import_key(const char *filename){

274

242

int ret;

275

243

int fd;

276

244

gpgme_data_t pgp_data;

283

251

284

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

285

253

if(rc != GPG_ERR_NO_ERROR){

286

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

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}

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258

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

259

rc = gpgme_op_import(mc.ctx, pgp_data);

292

260

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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263

return false;

296

264

}

297

265

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272

}

305

273

306

274

if(debug){

307

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

275

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

308

276

}

309

277

310

278

/* Init GPGME */

311

279

gpgme_check_version(NULL);

312

280

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

313

281

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));

282

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

283

gpgme_strsource(rc), gpgme_strerror(rc));

316

284

return false;

317

285

}

318

286

319

287

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

320

288

rc = gpgme_get_engine_info(&engine_info);

321

289

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));

290

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

291

gpgme_strsource(rc), gpgme_strerror(rc));

324

292

return false;

325

293

}

326

294

while(engine_info != NULL){

332

300

engine_info = engine_info->next;

333

301

}

334

302

if(engine_info == NULL){

335

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

336

tempdir);

303

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

337

304

return false;

338

305

}

339

306

340

307

/* Create new GPGME "context" */

341

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

308

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

342

309

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));

310

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

311

gpgme_strsource(rc), gpgme_strerror(rc));

346

312

return false;

347

313

}

348

314

357

323

* Decrypt OpenPGP data.

358

324

* Returns -1 on error

359

325

*/

360

__attribute__((nonnull, warn_unused_result))

361

326

static ssize_t pgp_packet_decrypt(const char *cryptotext,

362

327

size_t crypto_size,

363

char **plaintext,

364

mandos_context *mc){

328

char **plaintext){

365

329

gpgme_data_t dh_crypto, dh_plain;

366

330

gpgme_error_t rc;

367

331

ssize_t ret;

369

333

ssize_t plaintext_length = 0;

370

334

371

335

if(debug){

372

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

336

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

373

337

}

374

338

375

339

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

376

340

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

377

341

0);

378

342

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));

343

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

344

gpgme_strsource(rc), gpgme_strerror(rc));

381

345

return -1;

382

346

}

383

347

384

348

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

385

349

rc = gpgme_data_new(&dh_plain);

386

350

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));

351

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

352

gpgme_strsource(rc), gpgme_strerror(rc));

390

353

gpgme_data_release(dh_crypto);

391

354

return -1;

392

355

}

393

356

394

357

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

395

358

data buffer */

396

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

359

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

397

360

if(rc != GPG_ERR_NO_ERROR){

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

361

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

362

gpgme_strsource(rc), gpgme_strerror(rc));

400

363

plaintext_length = -1;

401

364

if(debug){

402

365

gpgme_decrypt_result_t result;

403

result = gpgme_op_decrypt_result(mc->ctx);

366

result = gpgme_op_decrypt_result(mc.ctx);

404

367

if(result == NULL){

405

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

368

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

406

369

} 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);

370

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

371

result->unsupported_algorithm);

372

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

373

result->wrong_key_usage);

411

374

if(result->file_name != NULL){

412

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

375

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

413

376

}

414

377

gpgme_recipient_t recipient;

415

378

recipient = result->recipients;

416

379

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");

380

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

381

gpgme_pubkey_algo_name(recipient->pubkey_algo));

382

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

383

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

384

recipient->status == GPG_ERR_NO_SECKEY

385

? "No" : "Yes");

424

386

recipient = recipient->next;

425

387

}

426

388

}

429

391

}

430

392

431

393

if(debug){

432

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

394

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

433

395

}

434

396

435

397

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

442

404

*plaintext = NULL;

443

405

while(true){

444

406

plaintext_capacity = incbuffer(plaintext,

445

(size_t)plaintext_length,

446

plaintext_capacity);

407

(size_t)plaintext_length,

408

plaintext_capacity);

447

409

if(plaintext_capacity == 0){

448

perror_plus("incbuffer");

449

plaintext_length = -1;

450

goto decrypt_end;

410

perror_plus("incbuffer");

411

plaintext_length = -1;

412

goto decrypt_end;

451

413

}

452

414

453

415

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

466

428

}

467

429

468

430

if(debug){

469

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

431

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

470

432

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

471

433

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

472

434

}

483

445

return plaintext_length;

484

446

}

485

447

486

__attribute__((warn_unused_result))

487

static const char *safer_gnutls_strerror(int value){

488

const char *ret = gnutls_strerror(value);

448

static const char * safer_gnutls_strerror(int value){

449

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

450

-Wunreachable-code */

489

451

if(ret == NULL)

490

452

ret = "(unknown)";

491

453

return ret;

492

454

}

493

455

494

456

/* GnuTLS log function callback */

495

__attribute__((nonnull))

496

457

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

497

458

const char* string){

498

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

459

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

499

460

}

500

461

501

__attribute__((nonnull, warn_unused_result))

502

462

static int init_gnutls_global(const char *pubkeyfilename,

503

const char *seckeyfilename,

504

mandos_context *mc){

463

const char *seckeyfilename){

505

464

int ret;

506

465

507

466

if(debug){

508

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

467

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

509

468

}

510

469

511

470

ret = gnutls_global_init();

512

471

if(ret != GNUTLS_E_SUCCESS){

513

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

514

safer_gnutls_strerror(ret));

472

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

473

safer_gnutls_strerror(ret));

515

474

return -1;

516

475

}

517

476

524

483

}

525

484

526

485

/* OpenPGP credentials */

527

ret = gnutls_certificate_allocate_credentials(&mc->cred);

486

ret = gnutls_certificate_allocate_credentials(&mc.cred);

528

487

if(ret != GNUTLS_E_SUCCESS){

529

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

530

safer_gnutls_strerror(ret));

488

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

489

safer_gnutls_strerror(ret));

531

490

gnutls_global_deinit();

532

491

return -1;

533

492

}

534

493

535

494

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);

495

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

496

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

497

seckeyfilename);

540

498

}

541

499

542

500

ret = gnutls_certificate_set_openpgp_key_file

543

(mc->cred, pubkeyfilename, seckeyfilename,

501

(mc.cred, pubkeyfilename, seckeyfilename,

544

502

GNUTLS_OPENPGP_FMT_BASE64);

545

503

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));

504

fprintf(stderr,

505

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

506

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

507

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

508

safer_gnutls_strerror(ret));

551

509

goto globalfail;

552

510

}

553

511

554

512

/* GnuTLS server initialization */

555

ret = gnutls_dh_params_init(&mc->dh_params);

513

ret = gnutls_dh_params_init(&mc.dh_params);

556

514

if(ret != GNUTLS_E_SUCCESS){

557

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

558

" initialization: %s\n",

559

safer_gnutls_strerror(ret));

515

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

516

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

560

517

goto globalfail;

561

518

}

562

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

519

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

563

520

if(ret != GNUTLS_E_SUCCESS){

564

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

565

safer_gnutls_strerror(ret));

521

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

522

safer_gnutls_strerror(ret));

566

523

goto globalfail;

567

524

}

568

525

569

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

526

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

570

527

571

528

return 0;

572

529

573

530

globalfail:

574

531

575

gnutls_certificate_free_credentials(mc->cred);

532

gnutls_certificate_free_credentials(mc.cred);

576

533

gnutls_global_deinit();

577

gnutls_dh_params_deinit(mc->dh_params);

534

gnutls_dh_params_deinit(mc.dh_params);

578

535

return -1;

579

536

}

580

537

581

__attribute__((nonnull, warn_unused_result))

582

static int init_gnutls_session(gnutls_session_t *session,

583

mandos_context *mc){

538

static int init_gnutls_session(gnutls_session_t *session){

584

539

int ret;

585

540

/* GnuTLS session creation */

586

541

do {

590

545

}

591

546

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

592

547

if(ret != GNUTLS_E_SUCCESS){

593

fprintf_plus(stderr,

594

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

595

safer_gnutls_strerror(ret));

548

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

549

safer_gnutls_strerror(ret));

596

550

}

597

551

598

552

{

599

553

const char *err;

600

554

do {

601

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

555

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

602

556

if(quit_now){

603

557

gnutls_deinit(*session);

604

558

return -1;

605

559

}

606

560

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

607

561

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));

562

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

563

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

564

safer_gnutls_strerror(ret));

611

565

gnutls_deinit(*session);

612

566

return -1;

613

567

}

615

569

616

570

do {

617

571

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

618

mc->cred);

572

mc.cred);

619

573

if(quit_now){

620

574

gnutls_deinit(*session);

621

575

return -1;

622

576

}

623

577

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

624

578

if(ret != GNUTLS_E_SUCCESS){

625

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

626

safer_gnutls_strerror(ret));

579

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

580

safer_gnutls_strerror(ret));

627

581

gnutls_deinit(*session);

628

582

return -1;

629

583

}

631

585

/* ignore client certificate if any. */

632

586

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

633

587

634

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

588

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

635

589

636

590

return 0;

637

591

}

641

595

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

642

596

643

597

/* 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,

598

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

646

599

AvahiIfIndex if_index,

647

int af, mandos_context *mc){

600

int af){

648

601

int ret, tcp_sd = -1;

649

602

ssize_t sret;

650

struct sockaddr_storage to;

603

union {

604

struct sockaddr_in in;

605

struct sockaddr_in6 in6;

606

} to;

651

607

char *buffer = NULL;

652

608

char *decrypted_buffer = NULL;

653

609

size_t buffer_length = 0;

672

628

pf = PF_INET;

673

629

break;

674

630

default:

675

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

631

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

676

632

errno = EINVAL;

677

633

return -1;

678

634

}

679

635

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);

636

ret = init_gnutls_session(&session);

713

637

if(ret != 0){

714

638

return -1;

715

639

}

716

640

717

641

if(debug){

718

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

719

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

642

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

643

"\n", ip, port);

720

644

}

721

645

722

646

tcp_sd = socket(pf, SOCK_STREAM, 0);

734

658

735

659

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

736

660

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);

661

to.in6.sin6_family = (sa_family_t)af;

662

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

739

663

} 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);

664

to.in.sin_family = (sa_family_t)af;

665

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

742

666

}

743

667

if(ret < 0 ){

744

668

int e = errno;

748

672

}

749

673

if(ret == 0){

750

674

int e = errno;

751

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

675

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

752

676

errno = e;

753

677

goto mandos_end;

754

678

}

755

679

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)){

680

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

681

-Wconversion and

682

-Wunreachable-code */

683

684

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

685

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

686

-Wunreachable-code*/

759

687

if(if_index == AVAHI_IF_UNSPEC){

760

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

761

" incomplete without a network interface\n");

688

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

689

" without a network interface\n");

762

690

errno = EINVAL;

763

691

goto mandos_end;

764

692

}

765

693

/* Set the network interface number as scope */

766

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

694

to.in6.sin6_scope_id = (uint32_t)if_index;

767

695

}

768

696

} else {

769

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

697

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

698

-Wconversion and

699

-Wunreachable-code */

770

700

}

771

701

772

702

if(quit_now){

780

710

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

781

711

perror_plus("if_indextoname");

782

712

} else {

783

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

784

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

713

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

714

ip, interface, port);

785

715

}

786

716

} else {

787

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

788

ip, (uintmax_t)port);

717

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

718

port);

789

719

}

790

720

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

791

721

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

722

const char *pcret;

792

723

if(af == AF_INET6){

793

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

794

sizeof(struct sockaddr_in6),

795

addrstr, sizeof(addrstr), NULL, 0,

796

NI_NUMERICHOST);

724

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

725

sizeof(addrstr));

797

726

} else {

798

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

799

sizeof(struct sockaddr_in),

800

addrstr, sizeof(addrstr), NULL, 0,

801

NI_NUMERICHOST);

727

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

728

sizeof(addrstr));

802

729

}

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);

730

if(pcret == NULL){

731

perror_plus("inet_ntop");

732

} else {

733

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

734

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

735

}

809

736

}

810

737

}

811

738

815

742

}

816

743

817

744

if(af == AF_INET6){

818

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

819

sizeof(struct sockaddr_in6));

745

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

820

746

} else {

821

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

822

sizeof(struct sockaddr_in));

747

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

823

748

}

824

749

if(ret < 0){

825

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

750

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

826

751

int e = errno;

827

752

perror_plus("connect");

828

753

errno = e;

840

765

while(true){

841

766

size_t out_size = strlen(out);

842

767

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

843

out_size - written));

768

out_size - written));

844

769

if(ret == -1){

845

770

int e = errno;

846

771

perror_plus("write");

866

791

}

867

792

868

793

if(debug){

869

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

794

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

870

795

}

871

796

872

797

if(quit_now){

874

799

goto mandos_end;

875

800

}

876

801

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);

802

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

803

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

882

804

883

805

if(quit_now){

884

806

errno = EINTR;

895

817

896

818

if(ret != GNUTLS_E_SUCCESS){

897

819

if(debug){

898

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

820

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

899

821

gnutls_perror(ret);

900

822

}

901

823

errno = EPROTO;

905

827

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

906

828

907

829

if(debug){

908

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

909

" %s\n", ip);

830

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

831

ip);

910

832

}

911

833

912

834

while(true){

917

839

}

918

840

919

841

buffer_capacity = incbuffer(&buffer, buffer_length,

920

buffer_capacity);

842

buffer_capacity);

921

843

if(buffer_capacity == 0){

922

844

int e = errno;

923

845

perror_plus("incbuffer");

950

872

}

951

873

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

952

874

if(ret < 0){

953

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

954

"***\n");

875

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

955

876

gnutls_perror(ret);

956

877

errno = EPROTO;

957

878

goto mandos_end;

958

879

}

959

880

break;

960

881

default:

961

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

962

" encrypted session with Mandos server\n");

882

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

883

" encrypted session with Mandos server\n");

963

884

gnutls_bye(session, GNUTLS_SHUT_RDWR);

964

885

errno = EIO;

965

886

goto mandos_end;

970

891

}

971

892

972

893

if(debug){

973

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

894

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

974

895

}

975

896

976

897

if(quit_now){

988

909

989

910

if(buffer_length > 0){

990

911

ssize_t decrypted_buffer_size;

991

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

992

&decrypted_buffer, mc);

912

decrypted_buffer_size = pgp_packet_decrypt(buffer,

913

buffer_length,

914

&decrypted_buffer);

993

915

if(decrypted_buffer_size >= 0){

994

916

995

917

written = 0;

1005

927

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

1006

928

int e = errno;

1007

929

if(debug){

1008

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

1009

strerror(errno));

930

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

931

strerror(errno));

1010

932

}

1011

933

errno = e;

1012

934

goto mandos_end;

1043

965

return retval;

1044

966

}

1045

967

1046

__attribute__((nonnull))

1047

968

static void resolve_callback(AvahiSServiceResolver *r,

1048

969

AvahiIfIndex interface,

1049

970

AvahiProtocol proto,

1057

978

AVAHI_GCC_UNUSED AvahiStringList *txt,

1058

979

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1059

980

flags,

1060

void *mc){

1061

if(r == NULL){

1062

return;

1063

}

981

AVAHI_GCC_UNUSED void* userdata){

982

assert(r);

1064

983

1065

984

/* Called whenever a service has been resolved successfully or

1066

985

timed out */

1072

991

switch(event){

1073

992

default:

1074

993

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)));

994

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

995

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

996

avahi_strerror(avahi_server_errno(mc.server)));

1080

997

break;

1081

998

1082

999

case AVAHI_RESOLVER_FOUND:

1084

1001

char ip[AVAHI_ADDRESS_STR_MAX];

1085

1002

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

1086

1003

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);

1004

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

1005

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

1006

ip, (intmax_t)interface, port);

1090

1007

}

1091

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

1092

interface,

1093

avahi_proto_to_af(proto),

1094

mc);

1008

int ret = start_mandos_communication(ip, port, interface,

1009

avahi_proto_to_af(proto));

1095

1010

if(ret == 0){

1096

avahi_simple_poll_quit(simple_poll);

1011

avahi_simple_poll_quit(mc.simple_poll);

1097

1012

} 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

}

1013

ret = add_server(ip, port, interface,

1014

avahi_proto_to_af(proto));

1104

1015

}

1105

1016

}

1106

1017

}

1116

1027

const char *domain,

1117

1028

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1118

1029

flags,

1119

void *mc){

1120

if(b == NULL){

1121

return;

1122

}

1030

AVAHI_GCC_UNUSED void* userdata){

1031

assert(b);

1123

1032

1124

1033

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

1125

1034

is removed from the LAN */

1132

1041

default:

1133

1042

case AVAHI_BROWSER_FAILURE:

1134

1043

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);

1044

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

1045

avahi_strerror(avahi_server_errno(mc.server)));

1046

avahi_simple_poll_quit(mc.simple_poll);

1139

1047

return;

1140

1048

1141

1049

case AVAHI_BROWSER_NEW:

1144

1052

the callback function is called the Avahi server will free the

1145

1053

resolver for us. */

1146

1054

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)));

1055

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

1056

name, type, domain, protocol, 0,

1057

resolve_callback, NULL) == NULL)

1058

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

1059

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

1155

1060

break;

1156

1061

1157

1062

case AVAHI_BROWSER_REMOVE:

1160

1065

case AVAHI_BROWSER_ALL_FOR_NOW:

1161

1066

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1162

1067

if(debug){

1163

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

1164

" searching...\n");

1068

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

1165

1069

}

1166

1070

break;

1167

1071

}

1176

1080

signal_received = sig;

1177

1081

int old_errno = errno;

1178

1082

/* set main loop to exit */

1179

if(simple_poll != NULL){

1180

avahi_simple_poll_quit(simple_poll);

1083

if(mc.simple_poll != NULL){

1084

avahi_simple_poll_quit(mc.simple_poll);

1181

1085

}

1182

1086

errno = old_errno;

1183

1087

}

1184

1088

1185

__attribute__((nonnull, warn_unused_result))

1186

1089

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

1187

1090

int ret;

1188

error_t ret_errno;

1189

1091

1190

1092

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

1191

1093

if(s < 0){

1192

ret_errno = errno;

1193

1094

perror_plus("socket");

1194

errno = ret_errno;

1195

1095

return false;

1196

1096

}

1197

1097

strcpy(ifr->ifr_name, ifname);

1198

1098

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1199

1099

if(ret == -1){

1200

1100

if(debug){

1201

ret_errno = errno;

1202

1101

perror_plus("ioctl SIOCGIFFLAGS");

1203

errno = ret_errno;

1204

1102

}

1205

1103

return false;

1206

1104

}

1207

1105

return true;

1208

1106

}

1209

1107

1210

__attribute__((nonnull, warn_unused_result))

1211

1108

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

1212

1109

1213

1110

/* Reject the loopback device */

1214

1111

if(ifr->ifr_flags & IFF_LOOPBACK){

1215

1112

if(debug){

1216

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

1217

ifname);

1113

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

1114

ifname);

1218

1115

}

1219

1116

return false;

1220

1117

}

1221

1118

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

1222

1119

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

1223

1120

if(debug){

1224

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

1225

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

1121

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

1122

ifname);

1226

1123

}

1227

1124

return true;

1228

1125

}

1229

1126

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

1230

1127

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

1231

1128

if(debug){

1232

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1233

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

1129

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

1130

ifname);

1234

1131

}

1235

1132

return false;

1236

1133

}

1237

1134

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

1238

1135

if(ifr->ifr_flags & IFF_NOARP){

1239

1136

if(debug){

1240

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

1241

ifname);

1137

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

1242

1138

}

1243

1139

return false;

1244

1140

}

1245

1141

1246

1142

/* Accept this device */

1247

1143

if(debug){

1248

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

1144

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

1249

1145

}

1250

1146

return true;

1251

1147

}

1255

1151

* corresponds to an acceptable network device.

1256

1152

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

1257

1153

*/

1258

__attribute__((nonnull, warn_unused_result))

1259

1154

int good_interface(const struct dirent *if_entry){

1155

int ret;

1260

1156

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

1261

1157

return 0;

1262

1158

}

1263

1264

1159

struct ifreq ifr;

1160

1265

1161

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

1162

return 0;

1271

1163

}

1272

1164

1277

1169

}

1278

1170

1279

1171

/*

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))

1172

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

1173

* corresponds to an acceptable network device which is up.

1174

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

1175

*/

1176

int up_interface(const struct dirent *if_entry){

1177

ssize_t ssret;

1178

char *flagname = NULL;

1179

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

1180

return 0;

1181

}

1182

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

1183

if_entry->d_name);

1184

if(ret < 0){

1185

perror_plus("asprintf");

1186

return 0;

1187

}

1188

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

1189

if(flags_fd == -1){

1190

perror_plus("open");

1191

free(flagname);

1192

return 0;

1193

}

1194

free(flagname);

1195

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

1196

/* read line from flags_fd */

1197

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

1198

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

1199

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

1200

if(flagstring == NULL){

1201

perror_plus("malloc");

1202

close(flags_fd);

1203

return 0;

1204

}

1205

while(to_read > 0){

1206

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

1207

(size_t)to_read));

1208

if(ssret == -1){

1209

perror_plus("read");

1210

free(flagstring);

1211

close(flags_fd);

1212

return 0;

1213

}

1214

to_read -= ssret;

1215

if(ssret == 0){

1216

break;

1217

}

1218

}

1219

close(flags_fd);

1220

intmax_t tmpmax;

1221

char *tmp;

1222

errno = 0;

1223

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

1224

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

1225

and not (isspace(*tmp)))

1226

or tmpmax != (ifreq_flags)tmpmax){

1227

if(debug){

1228

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

1229

flagstring, if_entry->d_name);

1230

}

1231

free(flagstring);

1232

return 0;

1233

}

1234

free(flagstring);

1235

ifreq_flags flags = (ifreq_flags)tmpmax;

1236

/* Reject the loopback device */

1237

if(flags & IFF_LOOPBACK){

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

/* Reject down interfaces */

1246

if(not (flags & IFF_UP)){

1247

return 0;

1248

}

1249

1250

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

1251

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

1252

if(debug){

1253

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

1254

if_entry->d_name);

1255

}

1256

return 1;

1257

}

1258

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

1259

if(not (flags & IFF_BROADCAST)){

1260

if(debug){

1261

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

1262

if_entry->d_name);

1263

}

1264

return 0;

1265

}

1266

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

1267

if(flags & IFF_NOARP){

1268

if(debug){

1269

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

1270

if_entry->d_name);

1271

}

1272

return 0;

1273

}

1274

/* Accept this device */

1275

if(debug){

1276

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

1277

if_entry->d_name);

1278

}

1279

return 1;

1280

}

1281

1314

1282

int notdotentries(const struct dirent *direntry){

1315

1283

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

1316

1284

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

1323

1291

}

1324

1292

1325

1293

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

1326

__attribute__((nonnull, warn_unused_result))

1327

1294

int runnable_hook(const struct dirent *direntry){

1328

1295

int ret;

1329

size_t sret;

1330

1296

struct stat st;

1331

1297

1332

1298

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

1334

1300

return 0;

1335

1301

}

1336

1302

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);

1303

/* Save pointer to last character */

1304

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

1305

1306

if(*end == '~'){

1307

/* Backup name~ */

1308

return 0;

1309

}

1310

1311

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

1312

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

1313

/* Temporary #name# */

1314

return 0;

1315

}

1316

1317

/* XXX more rules here */

1318

1319

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

1351

1320

if(ret == -1){

1352

1321

if(debug){

1353

perror_plus("Could not stat hook");

1322

perror_plus("Could not stat plugin");

1354

1323

}

1355

1324

return 0;

1356

1325

}

1357

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

1326

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

1358

1327

/* Not a regular file */

1359

if(debug){

1360

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

1361

direntry->d_name);

1362

}

1363

1328

return 0;

1364

1329

}

1365

1330

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

1366

1331

/* Not executable */

1367

if(debug){

1368

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

1369

direntry->d_name);

1370

}

1371

1332

return 0;

1372

1333

}

1373

if(debug){

1374

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

1375

direntry->d_name);

1376

}

1377

1334

return 1;

1378

1335

}

1379

1336

1380

__attribute__((nonnull, warn_unused_result))

1381

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1382

mandos_context *mc){

1337

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1383

1338

int ret;

1384

1339

struct timespec now;

1385

1340

struct timespec waited_time;

1386

1341

intmax_t block_time;

1387

1342

1388

1343

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");

1344

if(mc.current_server == NULL){

1345

if (debug){

1346

fprintf(stderr,

1347

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

1393

1348

}

1394

1349

ret = avahi_simple_poll_iterate(s, -1);

1395

1350

} else {

1396

if(debug){

1397

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

1398

" it, or wait\n");

1351

if (debug){

1352

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

1353

" or wait\n");

1399

1354

}

1400

1355

/* the current time */

1401

1356

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1406

1361

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

1407

1362

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

1408

1363

waited_time.tv_sec = (now.tv_sec

1409

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

1364

- mc.current_server->last_seen.tv_sec);

1410

1365

waited_time.tv_nsec = (now.tv_nsec

1411

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

1366

- mc.current_server->last_seen.tv_nsec);

1412

1367

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

1413

1368

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

1414

1369

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

1416

1371

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

1417

1372

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

1418

1373

1419

if(debug){

1420

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

1421

block_time);

1374

if (debug){

1375

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

1422

1376

}

1423

1377

1424

1378

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);

1379

ret = start_mandos_communication(mc.current_server->ip,

1380

mc.current_server->port,

1381

mc.current_server->if_index,

1382

mc.current_server->af);

1429

1383

if(ret == 0){

1430

avahi_simple_poll_quit(s);

1384

avahi_simple_poll_quit(mc.simple_poll);

1431

1385

return 0;

1432

1386

}

1433

1387

ret = clock_gettime(CLOCK_MONOTONIC,

1434

&mc->current_server->last_seen);

1388

&mc.current_server->last_seen);

1435

1389

if(ret == -1){

1436

1390

perror_plus("clock_gettime");

1437

1391

return -1;

1438

1392

}

1439

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

1393

mc.current_server = mc.current_server->next;

1440

1394

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

1441

1395

servers, but don't block */

1442

1396

}

1444

1398

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

1445

1399

}

1446

1400

if(ret != 0){

1447

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

1401

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

1448

1402

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

1449

1403

}

1450

1404

}

1451

1405

}

1452

1406

}

1453

1407

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

}

1462

errno = old_errno;

1463

return ret_errno;

1464

}

1465

1466

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

1467

__attribute__((warn_unused_result))

1468

error_t raise_privileges_permanently(void){

1469

error_t old_errno = errno;

1470

error_t ret_errno = raise_privileges();

1471

if(ret_errno != 0){

1472

errno = old_errno;

1473

return ret_errno;

1474

}

1475

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

1476

ret_errno = errno;

1477

}

1478

errno = old_errno;

1479

return ret_errno;

1480

}

1481

1482

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

1483

__attribute__((warn_unused_result))

1484

error_t lower_privileges(void){

1485

error_t old_errno = errno;

1486

error_t ret_errno = 0;

1487

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

1488

ret_errno = errno;

1489

}

1490

errno = old_errno;

1491

return ret_errno;

1492

}

1493

1494

/* Lower privileges permanently */

1495

__attribute__((warn_unused_result))

1496

error_t lower_privileges_permanently(void){

1497

error_t old_errno = errno;

1498

error_t ret_errno = 0;

1499

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

1500

ret_errno = errno;

1501

}

1502

errno = old_errno;

1503

return ret_errno;

1504

}

1505

1506

__attribute__((nonnull))

1507

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

1508

const float delay){

1509

struct dirent **direntries = NULL;

1510

if(hookdir_fd == -1){

1511

hookdir_fd = open(hookdir, O_RDONLY);

1512

if(hookdir_fd == -1){

1513

if(errno == ENOENT){

1514

if(debug){

1515

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

1516

" found\n", hookdir);

1517

}

1518

} else {

1519

perror_plus("open");

1520

}

1521

return;

1522

}

1523

}

1524

#ifdef __GLIBC__

1525

#if __GLIBC_PREREQ(2, 15)

1526

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

1527

runnable_hook, alphasort);

1528

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

1529

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

1530

alphasort);

1531

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

1532

#else /* not __GLIBC__ */

1533

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

1534

alphasort);

1535

#endif /* not __GLIBC__ */

1536

if(numhooks == -1){

1537

perror_plus("scandir");

1538

return;

1539

}

1540

struct dirent *direntry;

1541

int ret;

1542

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

1543

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

1544

direntry = direntries[i];

1545

if(debug){

1546

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

1547

direntry->d_name);

1548

}

1549

pid_t hook_pid = fork();

1550

if(hook_pid == 0){

1551

/* Child */

1552

/* Raise privileges */

1553

errno = raise_privileges_permanently();

1554

if(errno != 0){

1555

perror_plus("Failed to raise privileges");

1556

_exit(EX_NOPERM);

1557

}

1558

/* Set group */

1559

errno = 0;

1560

ret = setgid(0);

1561

if(ret == -1){

1562

perror_plus("setgid");

1563

_exit(EX_NOPERM);

1564

}

1565

/* Reset supplementary groups */

1566

errno = 0;

1567

ret = setgroups(0, NULL);

1568

if(ret == -1){

1569

perror_plus("setgroups");

1570

_exit(EX_NOPERM);

1571

}

1572

ret = dup2(devnull, STDIN_FILENO);

1573

if(ret == -1){

1574

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

1575

_exit(EX_OSERR);

1576

}

1577

ret = close(devnull);

1578

if(ret == -1){

1579

perror_plus("close");

1580

_exit(EX_OSERR);

1581

}

1582

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1583

if(ret == -1){

1584

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

1585

_exit(EX_OSERR);

1586

}

1587

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

1588

if(ret == -1){

1589

perror_plus("setenv");

1590

_exit(EX_OSERR);

1591

}

1592

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

1593

if(ret == -1){

1594

perror_plus("setenv");

1595

_exit(EX_OSERR);

1596

}

1597

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

1598

if(ret == -1){

1599

perror_plus("setenv");

1600

_exit(EX_OSERR);

1601

}

1602

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

1603

if(ret == -1){

1604

perror_plus("setenv");

1605

_exit(EX_OSERR);

1606

}

1607

char *delaystring;

1608

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

1609

if(ret == -1){

1610

perror_plus("asprintf");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

free(delaystring);

1616

perror_plus("setenv");

1617

_exit(EX_OSERR);

1618

}

1619

free(delaystring);

1620

if(connect_to != NULL){

1621

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

1622

if(ret == -1){

1623

perror_plus("setenv");

1624

_exit(EX_OSERR);

1625

}

1626

}

1627

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

1628

if(hook_fd == -1){

1629

perror_plus("openat");

1630

_exit(EXIT_FAILURE);

1631

}

1632

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

1633

perror_plus("close");

1634

_exit(EXIT_FAILURE);

1635

}

1636

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

1637

environ) == -1){

1638

perror_plus("fexecve");

1639

_exit(EXIT_FAILURE);

1640

}

1641

} else {

1642

int status;

1643

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

1644

perror_plus("waitpid");

1645

continue;

1646

}

1647

if(WIFEXITED(status)){

1648

if(WEXITSTATUS(status) != 0){

1649

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

1650

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

1651

WEXITSTATUS(status));

1652

continue;

1653

}

1654

} else if(WIFSIGNALED(status)){

1655

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

1656

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

1657

WTERMSIG(status));

1658

continue;

1659

} else {

1660

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

1661

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

1662

continue;

1663

}

1664

}

1665

if(debug){

1666

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

1667

direntry->d_name);

1668

}

1669

}

1670

free(direntries);

1671

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

1672

perror_plus("close");

1673

} else {

1674

hookdir_fd = -1;

1675

}

1676

close(devnull);

1677

}

1678

1679

__attribute__((nonnull, warn_unused_result))

1680

error_t bring_up_interface(const char *const interface,

1681

const float delay){

1682

error_t old_errno = errno;

1683

int ret;

1684

struct ifreq network;

1685

unsigned int if_index = if_nametoindex(interface);

1686

if(if_index == 0){

1687

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

1688

errno = old_errno;

1689

return ENXIO;

1690

}

1691

1692

if(quit_now){

1693

errno = old_errno;

1694

return EINTR;

1695

}

1696

1697

if(not interface_is_up(interface)){

1698

error_t ret_errno = 0, ioctl_errno = 0;

1699

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

1700

ret_errno = errno;

1701

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

1702

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

1703

errno = old_errno;

1704

return ret_errno;

1705

}

1706

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

1707

1708

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

1709

if(sd == -1){

1710

ret_errno = errno;

1711

perror_plus("socket");

1712

errno = old_errno;

1713

return ret_errno;

1714

}

1715

1716

if(quit_now){

1717

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

1718

if(ret == -1){

1719

perror_plus("close");

1720

}

1721

errno = old_errno;

1722

return EINTR;

1723

}

1724

1725

if(debug){

1726

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

1727

interface);

1728

}

1729

1730

/* Raise privileges */

1731

ret_errno = raise_privileges();

1732

if(ret_errno != 0){

1733

errno = ret_errno;

1734

perror_plus("Failed to raise privileges");

1735

}

1736

1737

#ifdef __linux__

1738

int ret_linux;

1739

bool restore_loglevel = false;

1740

if(ret_errno == 0){

1741

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1742

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

1743

ret_linux = klogctl(8, NULL, 5);

1744

if(ret_linux == -1){

1745

perror_plus("klogctl");

1746

} else {

1747

restore_loglevel = true;

1748

}

1749

}

1750

#endif /* __linux__ */

1751

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

1752

ioctl_errno = errno;

1753

#ifdef __linux__

1754

if(restore_loglevel){

1755

ret_linux = klogctl(7, NULL, 0);

1756

if(ret_linux == -1){

1757

perror_plus("klogctl");

1758

}

1759

}

1760

#endif /* __linux__ */

1761

1762

/* If raise_privileges() succeeded above */

1763

if(ret_errno == 0){

1764

/* Lower privileges */

1765

ret_errno = lower_privileges();

1766

if(ret_errno != 0){

1767

errno = ret_errno;

1768

perror_plus("Failed to lower privileges");

1769

}

1770

}

1771

1772

/* Close the socket */

1773

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

1774

if(ret == -1){

1775

perror_plus("close");

1776

}

1777

1778

if(ret_setflags == -1){

1779

errno = ioctl_errno;

1780

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1781

errno = old_errno;

1782

return ioctl_errno;

1783

}

1784

} else if(debug){

1785

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

1786

interface);

1787

}

1788

1789

/* Sleep checking until interface is running.

1790

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

1791

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

1792

if(interface_is_running(interface)){

1793

break;

1794

}

1795

struct timespec sleeptime = { .tv_nsec = 250000000 };

1796

ret = nanosleep(&sleeptime, NULL);

1797

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

1798

perror_plus("nanosleep");

1799

}

1800

}

1801

1802

errno = old_errno;

1803

return 0;

1804

}

1805

1806

__attribute__((nonnull, warn_unused_result))

1807

error_t take_down_interface(const char *const interface){

1808

error_t old_errno = errno;

1809

struct ifreq network;

1810

unsigned int if_index = if_nametoindex(interface);

1811

if(if_index == 0){

1812

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

1813

errno = old_errno;

1814

return ENXIO;

1815

}

1816

if(interface_is_up(interface)){

1817

error_t ret_errno = 0, ioctl_errno = 0;

1818

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

1819

ret_errno = errno;

1820

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

1821

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

1822

errno = old_errno;

1823

return ret_errno;

1824

}

1825

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

1826

1827

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

1828

if(sd == -1){

1829

ret_errno = errno;

1830

perror_plus("socket");

1831

errno = old_errno;

1832

return ret_errno;

1833

}

1834

1835

if(debug){

1836

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

1837

interface);

1838

}

1839

1840

/* Raise privileges */

1841

ret_errno = raise_privileges();

1842

if(ret_errno != 0){

1843

errno = ret_errno;

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

1408

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

1409

AvahiSServiceBrowser *sb = NULL;

1887

error_t ret_errno;

1410

int error;

1888

1411

int ret;

1889

1412

intmax_t tmpmax;

1890

1413

char *tmp;

1891

1414

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;

1415

const char *interface = "";

1416

struct ifreq network;

1417

int sd = -1;

1418

bool take_down_interface = false;

1419

uid_t uid;

1420

gid_t gid;

1421

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

1422

bool tempdir_created = false;

1897

1423

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1898

1424

const char *seckey = PATHDIR "/" SECKEY;

1899

1425

const char *pubkey = PATHDIR "/" PUBKEY;

1900

char *interfaces_hooks = NULL;

1901

1426

1902

1427

bool gnutls_initialized = false;

1903

1428

bool gpgme_initialized = false;

1965

1490

.group = 2 },

1966

1491

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

1967

1492

.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",

1493

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

1973

1494

.group = 2 },

1974

1495

/*

1975

1496

* These reproduce what we would get without ARGP_NO_HELP

1994

1515

connect_to = arg;

1995

1516

break;

1996

1517

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

}

1518

interface = arg;

2002

1519

break;

2003

1520

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

2004

1521

seckey = arg;

2033

1550

argp_error(state, "Bad retry interval");

2034

1551

}

2035

1552

break;

2036

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

2037

hookdir = arg;

2038

break;

2039

1553

/*

2040

1554

* These reproduce what we would get without ARGP_NO_HELP

2041

1555

*/

2047

1561

argp_state_help(state, state->out_stream,

2048

1562

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2049

1563

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

2050

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

1564

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

2051

1565

exit(argp_err_exit_status);

2052

1566

break;

2053

1567

default:

2080

1594

{

2081

1595

/* Work around Debian bug #633582:

2082

1596

<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");

1597

struct stat st;

1598

1599

/* Re-raise priviliges */

1600

errno = 0;

1601

ret = seteuid(0);

1602

if(ret == -1){

1603

perror_plus("seteuid");

1604

}

1605

1606

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

1607

int seckey_fd = open(seckey, O_RDONLY);

1608

if(seckey_fd == -1){

1609

perror_plus("open");

1610

} else {

1611

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

1612

if(ret == -1){

1613

perror_plus("fstat");

1614

} else {

1615

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

1616

ret = fchown(seckey_fd, uid, gid);

1617

if(ret == -1){

1618

perror_plus("fchown");

1619

}

1620

}

1621

}

1622

TEMP_FAILURE_RETRY(close(seckey_fd));

1623

}

1624

}

1625

1626

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

1627

int pubkey_fd = open(pubkey, O_RDONLY);

1628

if(pubkey_fd == -1){

1629

perror_plus("open");

1630

} else {

1631

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

1632

if(ret == -1){

1633

perror_plus("fstat");

1634

} else {

1635

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

1636

ret = fchown(pubkey_fd, uid, gid);

1637

if(ret == -1){

1638

perror_plus("fchown");

1639

}

1640

}

1641

}

1642

TEMP_FAILURE_RETRY(close(pubkey_fd));

1643

}

1644

}

1645

1646

/* Lower privileges */

1647

errno = 0;

1648

ret = seteuid(uid);

1649

if(ret == -1){

1650

perror_plus("seteuid");

1651

}

1652

}

1653

1654

/* Find network hooks and run them */

1655

{

1656

struct dirent **direntries;

1657

struct dirent *direntry;

1658

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

1659

alphasort);

1660

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

1661

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

1662

direntry = direntries[0];

1663

char *fullname = NULL;

1664

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

1665

direntry->d_name);

1666

if(ret < 0){

1667

perror_plus("asprintf");

1668

continue;

1669

}

1670

pid_t hook_pid = fork();

1671

if(hook_pid == 0){

1672

/* Child */

1673

dup2(devnull, STDIN_FILENO);

1674

close(devnull);

1675

dup2(STDERR_FILENO, STDOUT_FILENO);

1676

setenv("DEVICE", interface, 1);

1677

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

1678

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

1679

/* setenv( XXX more here */

1680

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

1681

perror_plus("execl");

1682

}

1683

free(fullname);

1684

if(quit_now){

2166

1685

goto end;

2167

1686

}

2168

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

2169

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

2170

1687

}

2171

run_network_hooks("start", interfaces_hooks != NULL ?

2172

interfaces_hooks : "", delay);

1688

close(devnull);

2173

1689

}

2174

1690

2175

1691

if(not debug){

2176

1692

avahi_set_log_function(empty_log);

2177

1693

}

2178

1694

1695

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

1696

struct dirent **direntries;

1697

ret = scandir(sys_class_net, &direntries, good_interface,

1698

alphasort);

1699

if(ret >= 1){

1700

/* Pick the first good interface */

1701

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

1702

if(debug){

1703

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

1704

}

1705

if(interface == NULL){

1706

perror_plus("malloc");

1707

free(direntries);

1708

exitcode = EXIT_FAILURE;

1709

goto end;

1710

}

1711

free(direntries);

1712

} else {

1713

free(direntries);

1714

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

1715

exitcode = EXIT_FAILURE;

1716

goto end;

1717

}

1718

}

1719

2179

1720

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

2180

1721

from the signal handler */

2181

1722

/* Initialize the pseudo-RNG for Avahi */

2182

1723

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");

1724

mc.simple_poll = avahi_simple_poll_new();

1725

if(mc.simple_poll == NULL){

1726

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

2187

1727

exitcode = EX_UNAVAILABLE;

2188

1728

goto end;

2189

1729

}

2251

1791

}

2252

1792

}

2253

1793

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);

1794

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

1795

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

1796

if_index = (AvahiIfIndex) if_nametoindex(interface);

1797

if(if_index == 0){

1798

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

1799

exitcode = EX_UNAVAILABLE;

1800

goto end;

1801

}

1802

1803

if(quit_now){

1804

goto end;

1805

}

1806

1807

/* Re-raise priviliges */

1808

errno = 0;

1809

ret = seteuid(0);

1810

if(ret == -1){

1811

perror_plus("seteuid");

1812

}

1813

1814

#ifdef __linux__

1815

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1816

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

1817

ret = klogctl(8, NULL, 5);

1818

bool restore_loglevel = true;

1819

if(ret == -1){

1820

restore_loglevel = false;

1821

perror_plus("klogctl");

1822

}

1823

#endif /* __linux__ */

1824

1825

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1826

if(sd < 0){

1827

perror_plus("socket");

1828

exitcode = EX_OSERR;

1829

#ifdef __linux__

1830

if(restore_loglevel){

1831

ret = klogctl(7, NULL, 0);

1832

if(ret == -1){

1833

perror_plus("klogctl");

1834

}

1835

}

1836

#endif /* __linux__ */

1837

/* Lower privileges */

1838

errno = 0;

1839

ret = seteuid(uid);

1840

if(ret == -1){

1841

perror_plus("seteuid");

1842

}

1843

goto end;

1844

}

1845

strcpy(network.ifr_name, interface);

1846

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

1847

if(ret == -1){

1848

perror_plus("ioctl SIOCGIFFLAGS");

1849

#ifdef __linux__

1850

if(restore_loglevel){

1851

ret = klogctl(7, NULL, 0);

1852

if(ret == -1){

1853

perror_plus("klogctl");

1854

}

1855

}

1856

#endif /* __linux__ */

1857

exitcode = EX_OSERR;

1858

/* Lower privileges */

1859

errno = 0;

1860

ret = seteuid(uid);

1861

if(ret == -1){

1862

perror_plus("seteuid");

1863

}

1864

goto end;

1865

}

1866

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

1867

network.ifr_flags |= IFF_UP;

1868

take_down_interface = true;

1869

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

1870

if(ret == -1){

1871

take_down_interface = false;

1872

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1873

exitcode = EX_OSERR;

1874

#ifdef __linux__

1875

if(restore_loglevel){

1876

ret = klogctl(7, NULL, 0);

1877

if(ret == -1){

1878

perror_plus("klogctl");

1879

}

1880

}

1881

#endif /* __linux__ */

1882

/* Lower privileges */

1883

errno = 0;

1884

ret = seteuid(uid);

1885

if(ret == -1){

1886

perror_plus("seteuid");

1887

}

1888

goto end;

1889

}

1890

}

1891

/* Sleep checking until interface is running.

1892

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

1893

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

1894

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

1895

if(ret == -1){

1896

perror_plus("ioctl SIOCGIFFLAGS");

1897

} else if(network.ifr_flags & IFF_RUNNING){

1898

break;

1899

}

1900

struct timespec sleeptime = { .tv_nsec = 250000000 };

1901

ret = nanosleep(&sleeptime, NULL);

1902

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

1903

perror_plus("nanosleep");

1904

}

1905

}

1906

if(not take_down_interface){

1907

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

1908

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

1909

if(ret == -1){

1910

perror_plus("close");

1911

}

1912

}

1913

#ifdef __linux__

1914

if(restore_loglevel){

1915

/* Restores kernel loglevel to default */

1916

ret = klogctl(7, NULL, 0);

1917

if(ret == -1){

1918

perror_plus("klogctl");

1919

}

1920

}

1921

#endif /* __linux__ */

1922

/* Lower privileges */

1923

errno = 0;

1924

if(take_down_interface){

1925

/* Lower privileges */

1926

ret = seteuid(uid);

1927

if(ret == -1){

1928

perror_plus("seteuid");

1929

}

2276

1930

} else {

2277

if(ret == 0){

2278

free(direntries);

2279

}

2280

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

2281

exitcode = EXIT_FAILURE;

2282

goto end;

2283

}

2284

}

2285

2286

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

2287

{

2288

char *interface = NULL;

2289

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

2290

interface))){

2291

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

2292

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

2293

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

2294

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

2295

interface);

2296

interface = NULL;

2297

while((interface = argz_next(mc.interfaces,

2298

mc.interfaces_size, interface))){

2299

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

2300

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

2301

interface);

2302

interface = NULL;

2303

}

2304

}

2305

break;

2306

}

2307

bool interface_was_up = interface_is_up(interface);

2308

errno = bring_up_interface(interface, delay);

2309

if(not interface_was_up){

2310

if(errno != 0){

2311

perror_plus("Failed to bring up interface");

2312

} else {

2313

errno = argz_add(&interfaces_to_take_down,

2314

&interfaces_to_take_down_size,

2315

interface);

2316

if(errno != 0){

2317

perror_plus("argz_add");

2318

}

2319

}

2320

}

2321

}

2322

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

2323

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

2324

}

2325

}

2326

2327

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

2328

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

2329

if(debug){

2330

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

2331

mc.interfaces);

2332

}

2333

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

1931

/* Lower privileges permanently */

1932

ret = setuid(uid);

1933

if(ret == -1){

1934

perror_plus("setuid");

1935

}

1936

}

2334

1937

}

2335

1938

2336

1939

if(quit_now){

2337

1940

goto end;

2338

1941

}

2339

1942

2340

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

1943

ret = init_gnutls_global(pubkey, seckey);

2341

1944

if(ret == -1){

2342

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

1945

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

2343

1946

exitcode = EX_UNAVAILABLE;

2344

1947

goto end;

2345

1948

} else {

2350

1953

goto end;

2351

1954

}

2352

1955

2353

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

2354

tempdir = mkdtemp(run_tempdir);

2355

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

2356

if(debug){

2357

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

2358

run_tempdir, old_tempdir);

2359

}

2360

tempdir = mkdtemp(old_tempdir);

2361

}

2362

if(tempdir == NULL){

1956

if(mkdtemp(tempdir) == NULL){

2363

1957

perror_plus("mkdtemp");

2364

1958

goto end;

2365

1959

}

1960

tempdir_created = true;

2366

1961

2367

1962

if(quit_now){

2368

1963

goto end;

2369

1964

}

2370

1965

2371

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

2372

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

1966

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

1967

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

2373

1968

exitcode = EX_UNAVAILABLE;

2374

1969

goto end;

2375

1970

} else {

2384

1979

/* Connect directly, do not use Zeroconf */

2385

1980

/* (Mainly meant for debugging) */

2386

1981

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

2387

2388

1982

if(address == NULL){

2389

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

1983

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

2390

1984

exitcode = EX_USAGE;

2391

1985

goto end;

2392

1986

}

2395

1989

goto end;

2396

1990

}

2397

1991

2398

in_port_t port;

1992

uint16_t port;

2399

1993

errno = 0;

2400

1994

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

2401

1995

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

2402

or tmpmax != (in_port_t)tmpmax){

2403

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

1996

or tmpmax != (uint16_t)tmpmax){

1997

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

2404

1998

exitcode = EX_USAGE;

2405

1999

goto end;

2406

2000

}

2407

2001

2408

2002

if(quit_now){

2409

2003

goto end;

2410

2004

}

2411

2005

2412

port = (in_port_t)tmpmax;

2006

port = (uint16_t)tmpmax;

2413

2007

*address = '\0';

2414

2008

/* Colon in address indicates IPv6 */

2415

2009

int af;

2431

2025

}

2432

2026

2433

2027

while(not quit_now){

2434

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

2435

&mc);

2028

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

2436

2029

if(quit_now or ret == 0){

2437

2030

break;

2438

2031

}

2439

2032

if(debug){

2440

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

2441

(int)retry_interval);

2033

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

2034

(int)retry_interval);

2442

2035

}

2443

sleep((unsigned int)retry_interval);

2036

sleep((int)retry_interval);

2444

2037

}

2445

2038

2446

if(not quit_now){

2039

if (not quit_now){

2447

2040

exitcode = EXIT_SUCCESS;

2448

2041

}

2449

2042

2464

2057

config.publish_domain = 0;

2465

2058

2466

2059

/* Allocate a new server */

2467

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2468

&config, NULL, NULL, &ret_errno);

2060

mc.server = avahi_server_new(avahi_simple_poll_get

2061

(mc.simple_poll), &config, NULL,

2062

NULL, &error);

2469

2063

2470

2064

/* Free the Avahi configuration data */

2471

2065

avahi_server_config_free(&config);

2473

2067

2474

2068

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

2475

2069

if(mc.server == NULL){

2476

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

2477

avahi_strerror(ret_errno));

2070

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

2071

avahi_strerror(error));

2478

2072

exitcode = EX_UNAVAILABLE;

2479

2073

goto end;

2480

2074

}

2486

2080

/* Create the Avahi service browser */

2487

2081

sb = avahi_s_service_browser_new(mc.server, if_index,

2488

2082

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2489

NULL, 0, browse_callback,

2490

(void *)&mc);

2083

NULL, 0, browse_callback, NULL);

2491

2084

if(sb == NULL){

2492

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

2493

avahi_strerror(avahi_server_errno(mc.server)));

2085

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

2086

avahi_strerror(avahi_server_errno(mc.server)));

2494

2087

exitcode = EX_UNAVAILABLE;

2495

2088

goto end;

2496

2089

}

2502

2095

/* Run the main loop */

2503

2096

2504

2097

if(debug){

2505

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

2098

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

2506

2099

}

2507

2508

ret = avahi_loop_with_timeout(simple_poll,

2509

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

2100

2101

ret = avahi_loop_with_timeout(mc.simple_poll,

2102

(int)(retry_interval * 1000));

2510

2103

if(debug){

2511

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

2512

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

2104

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

2105

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

2513

2106

}

2514

2107

2515

2108

end:

2516

2109

2517

2110

if(debug){

2518

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

2111

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

2519

2112

}

2520

2113

2521

2114

/* Cleanup things */

2522

free(mc.interfaces);

2523

2524

2115

if(sb != NULL)

2525

2116

avahi_s_service_browser_free(sb);

2526

2117

2527

2118

if(mc.server != NULL)

2528

2119

avahi_server_free(mc.server);

2529

2120

2530

if(simple_poll != NULL)

2531

avahi_simple_poll_free(simple_poll);

2121

if(mc.simple_poll != NULL)

2122

avahi_simple_poll_free(mc.simple_poll);

2532

2123

2533

2124

if(gnutls_initialized){

2534

2125

gnutls_certificate_free_credentials(mc.cred);

2539

2130

if(gpgme_initialized){

2540

2131

gpgme_release(mc.ctx);

2541

2132

}

2542

2133

2543

2134

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

2544

2135

has seen */

2545

2136

if(mc.current_server != NULL){

2551

2142

}

2552

2143

}

2553

2144

2554

/* Re-raise privileges */

2555

{

2556

ret_errno = raise_privileges();

2557

if(ret_errno != 0){

2558

errno = ret_errno;

2559

perror_plus("Failed to raise privileges");

2560

} else {

2561

2562

/* Run network hooks */

2563

run_network_hooks("stop", interfaces_hooks != NULL ?

2564

interfaces_hooks : "", delay);

2565

2566

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

2567

{

2568

char *interface = NULL;

2569

while((interface=argz_next(interfaces_to_take_down,

2570

interfaces_to_take_down_size,

2571

interface))){

2572

ret_errno = take_down_interface(interface);

2573

if(ret_errno != 0){

2574

errno = ret_errno;

2575

perror_plus("Failed to take down interface");

2576

}

2577

}

2578

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

2579

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

2580

" down\n");

2581

}

2582

}

2145

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

2146

2147

/* Take down the network interface */

2148

if(take_down_interface){

2149

/* Re-raise priviliges */

2150

errno = 0;

2151

ret = seteuid(0);

2152

if(ret == -1){

2153

perror_plus("seteuid");

2583

2154

}

2584

2585

ret_errno = lower_privileges_permanently();

2586

if(ret_errno != 0){

2587

errno = ret_errno;

2588

perror_plus("Failed to lower privileges permanently");

2155

if(geteuid() == 0){

2156

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

2157

if(ret == -1){

2158

perror_plus("ioctl SIOCGIFFLAGS");

2159

} else if(network.ifr_flags & IFF_UP) {

2160

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

2161

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

2162

if(ret == -1){

2163

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2164

}

2165

}

2166

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

2167

if(ret == -1){

2168

perror_plus("close");

2169

}

2170

/* Lower privileges permanently */

2171

errno = 0;

2172

ret = setuid(uid);

2173

if(ret == -1){

2174

perror_plus("setuid");

2175

}

2589

2176

}

2590

2177

}

2591

2178

2592

free(interfaces_to_take_down);

2593

free(interfaces_hooks);

2594

2595

2179

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

2596

if(tempdir != NULL){

2180

if(tempdir_created){

2597

2181

struct dirent **direntries = NULL;

2598

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

2599

O_NOFOLLOW));

2600

if(tempdir_fd == -1){

2601

perror_plus("open");

2602

} else {

2603

#ifdef __GLIBC__

2604

#if __GLIBC_PREREQ(2, 15)

2605

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

2606

notdotentries, alphasort);

2607

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

2608

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

2609

alphasort);

2610

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

2611

#else /* not __GLIBC__ */

2612

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

2613

alphasort);

2614

#endif /* not __GLIBC__ */

2615

if(numentries >= 0){

2616

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

2617

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

2618

if(ret == -1){

2619

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

2620

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

2621

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

2622

}

2623

}

2624

2625

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

2626

free(direntries);

2627

if(numentries == -1){

2628

perror_plus("scandir");

2629

}

2630

ret = rmdir(tempdir);

2631

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

2632

perror_plus("rmdir");

2633

}

2182

struct dirent *direntry = NULL;

2183

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

2184

alphasort);

2185

if (numentries > 0){

2186

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

2187

direntry = direntries[i];

2188

char *fullname = NULL;

2189

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

2190

direntry->d_name);

2191

if(ret < 0){

2192

perror_plus("asprintf");

2193

continue;

2194

}

2195

ret = remove(fullname);

2196

if(ret == -1){

2197

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

2198

strerror(errno));

2199

}

2200

free(fullname);

2634

2201

}

2635

TEMP_FAILURE_RETRY(close(tempdir_fd));

2202

}

2203

2204

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

2205

free(direntries);

2206

if (numentries == -1){

2207

perror_plus("scandir");

2208

}

2209

ret = rmdir(tempdir);

2210

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

2211

perror_plus("rmdir");

2636

2212

}

2637

2213

}

2638

2214