/mandos/release : revision 237.7.360

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* "browse_callback", and parts of "main".

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*

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* Everything else is

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*

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* This program is free software: you can redistribute it and/or

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* modify it under the terms of the GNU General Public License as

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* along with this program. If not, see

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* <http://www.gnu.org/licenses/>.

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*

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* Contact the authors at <mandos@fukt.bsnet.se>.

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* Contact the authors at <mandos@recompile.se>.

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*/

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/* 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

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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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(), remove() */

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

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stdout, ferror() */

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

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

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

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strtof(), abort() */

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#include <stdbool.h> /* bool, false, true */

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#include <string.h> /* memset(), strcmp(), strlen(),

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strerror(), asprintf(), strcpy() */

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#include <string.h> /* strcmp(), strlen(), strerror(),

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asprintf(), strncpy() */

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#include <sys/ioctl.h> /* ioctl */

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#include <sys/types.h> /* socket(), inet_pton(), sockaddr,

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

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

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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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#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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#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,

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SIOCSIFFLAGS, if_indextoname(),

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*/

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#include <unistd.h> /* close(), SEEK_SET, off_t, write(),

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getuid(), getgid(), seteuid(),

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setgid(), pause() */

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

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

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

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argp_state, struct argp,

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raise() */

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#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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#include <sys/wait.h> /* waitpid(), WIFEXITED(),

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WEXITSTATUS(), WTERMSIG() */

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#include <grp.h> /* setgroups() */

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#include <argz.h> /* argz_add_sep(), argz_next(),

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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118

init_gnutls_session(),

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119

GNUTLS_* */

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120

#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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125

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

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133

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

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134

#define SECKEY "seckey.txt"

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135

#define PUBKEY "pubkey.txt"

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

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137

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bool debug = false;

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139

static const char mandos_protocol_version[] = "1";

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const char *argp_program_version = "mandos-client " VERSION;

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

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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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143

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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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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161

typedef struct {

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AvahiSimplePoll *simple_poll;

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162

AvahiServer *server;

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163

gnutls_certificate_credentials_t cred;

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164

unsigned int dh_bits;

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165

gnutls_dh_params_t dh_params;

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166

const char *priority;

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167

gpgme_ctx_t ctx;

168

server *current_server;

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char *interfaces;

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size_t interfaces_size;

142

171

} mandos_context;

143

172

144

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

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

146

.dh_bits = 1024, .priority = "SECURE256"

147

":!CTYPE-X.509:+CTYPE-OPENPGP" };

173

/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

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175

149

176

sig_atomic_t quit_now = 0;

150

177

int signal_received = 0;

151

178

179

/* Function to use when printing errors */

180

void perror_plus(const char *print_text){

181

int e = errno;

182

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

183

program_invocation_short_name);

184

errno = e;

185

perror(print_text);

186

}

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188

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

189

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

190

va_list ap;

191

va_start (ap, format);

192

193

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

194

program_invocation_short_name));

195

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

196

}

197

152

198

/*

153

199

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

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200

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

155

201

* "buffer_length" is how much is already used.

156

202

*/

203

__attribute__((nonnull, warn_unused_result))

157

204

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

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206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

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

161

if(buffer == NULL){

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

208

if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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214

}

215

*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

165

217

}

166

218

return buffer_capacity;

167

219

}

168

220

221

/* 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){

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int ret;

226

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

227

if(new_server == NULL){

228

perror_plus("malloc");

229

return false;

230

}

231

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

232

.port = port,

233

.if_index = if_index,

234

.af = af };

235

if(new_server->ip == NULL){

236

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

253

}

254

/* Special case of first server */

255

if(*current_server == NULL){

256

new_server->next = new_server;

257

new_server->prev = new_server;

258

*current_server = new_server;

259

} else {

260

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

261

new_server->next = *current_server;

262

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

263

new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

266

return true;

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}

268

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/*

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* Initialize GPGME.

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271

*/

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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277

gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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279

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178

280

/*

179

281

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

180

282

*/

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bool import_key(const char *filename){

283

bool import_key(const char * const filename){

182

284

int ret;

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285

int fd;

184

286

gpgme_data_t pgp_data;

185

287

186

288

fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));

187

289

if(fd == -1){

188

perror("open");

290

perror_plus("open");

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291

return false;

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292

}

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

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295

if(rc != GPG_ERR_NO_ERROR){

194

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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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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return false;

197

299

}

198

300

199

rc = gpgme_op_import(mc.ctx, pgp_data);

301

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

200

302

if(rc != GPG_ERR_NO_ERROR){

201

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

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gpgme_strsource(rc), gpgme_strerror(rc));

303

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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305

return false;

204

306

}

205

307

206

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

308

ret = close(fd);

207

309

if(ret == -1){

208

perror("close");

310

perror_plus("close");

209

311

}

210

312

gpgme_data_release(pgp_data);

211

313

return true;

212

314

}

213

315

214

316

if(debug){

215

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

317

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

216

318

}

217

319

218

320

/* Init GPGME */

219

321

gpgme_check_version(NULL);

220

322

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

221

323

if(rc != GPG_ERR_NO_ERROR){

222

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

223

gpgme_strsource(rc), gpgme_strerror(rc));

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

224

326

return false;

225

327

}

226

328

227

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

329

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

228

330

rc = gpgme_get_engine_info(&engine_info);

229

331

if(rc != GPG_ERR_NO_ERROR){

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

232

334

return false;

233

335

}

234

336

while(engine_info != NULL){

240

342

engine_info = engine_info->next;

241

343

}

242

344

if(engine_info == NULL){

243

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

345

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

346

tempdir);

244

347

return false;

245

348

}

246

349

247

350

/* Create new GPGME "context" */

248

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

351

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

249

352

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

353

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

354

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

355

gpgme_strerror(rc));

252

356

return false;

253

357

}

254

358

263

367

* Decrypt OpenPGP data.

264

368

* Returns -1 on error

265

369

*/

370

__attribute__((nonnull, warn_unused_result))

266

371

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

372

size_t crypto_size,

268

char **plaintext){

373

char **plaintext,

374

mandos_context *mc){

269

375

gpgme_data_t dh_crypto, dh_plain;

270

376

gpgme_error_t rc;

271

377

ssize_t ret;

273

379

ssize_t plaintext_length = 0;

274

380

275

381

if(debug){

276

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

382

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

277

383

}

278

384

279

385

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

280

386

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

387

0);

282

388

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

285

391

return -1;

286

392

}

287

393

288

394

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

289

395

rc = gpgme_data_new(&dh_plain);

290

396

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

293

400

gpgme_data_release(dh_crypto);

294

401

return -1;

295

402

}

296

403

297

404

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

298

405

data buffer */

299

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

406

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

300

407

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

303

410

plaintext_length = -1;

304

411

if(debug){

305

412

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

413

result = gpgme_op_decrypt_result(mc->ctx);

307

414

if(result == NULL){

308

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

415

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

309

416

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

314

421

if(result->file_name != NULL){

315

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

422

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

316

423

}

317

424

gpgme_recipient_t recipient;

318

425

recipient = result->recipients;

319

426

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

326

434

recipient = recipient->next;

327

435

}

328

436

}

331

439

}

332

440

333

441

if(debug){

334

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

442

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

335

443

}

336

444

337

445

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

338

446

if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){

339

perror("gpgme_data_seek");

447

perror_plus("gpgme_data_seek");

340

448

plaintext_length = -1;

341

449

goto decrypt_end;

342

450

}

344

452

*plaintext = NULL;

345

453

while(true){

346

454

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

455

(size_t)plaintext_length,

456

plaintext_capacity);

349

457

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

353

461

}

354

462

355

463

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

468

break;

361

469

}

362

470

if(ret < 0){

363

perror("gpgme_data_read");

471

perror_plus("gpgme_data_read");

364

472

plaintext_length = -1;

365

473

goto decrypt_end;

366

474

}

368

476

}

369

477

370

478

if(debug){

371

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

479

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

372

480

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

373

481

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

374

482

}

385

493

return plaintext_length;

386

494

}

387

495

388

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

391

if(ret == NULL)

392

ret = "(unknown)";

393

return ret;

496

__attribute__((warn_unused_result, const))

497

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

498

if(str == NULL)

499

return "(unknown)";

500

return str;

501

}

502

503

__attribute__((warn_unused_result))

504

static const char *safer_gnutls_strerror(int value){

505

const char *ret = gnutls_strerror(value);

506

return safe_string(ret);

394

507

}

395

508

396

509

/* GnuTLS log function callback */

510

__attribute__((nonnull))

397

511

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

398

512

const char* string){

399

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

513

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

400

514

}

401

515

516

__attribute__((nonnull(1, 2, 4), warn_unused_result))

402

517

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

518

const char *seckeyfilename,

519

const char *dhparamsfilename,

520

mandos_context *mc){

404

521

int ret;

522

unsigned int uret;

405

523

406

524

if(debug){

407

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

408

}

409

410

ret = gnutls_global_init();

411

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

414

return -1;

525

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

415

526

}

416

527

417

528

if(debug){

423

534

}

424

535

425

536

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

538

if(ret != GNUTLS_E_SUCCESS){

428

fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

433

gnutls_global_deinit();

539

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

540

safer_gnutls_strerror(ret));

434

541

return -1;

435

542

}

436

543

437

544

if(debug){

438

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

439

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

440

seckeyfilename);

545

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

546

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

547

pubkeyfilename,

548

seckeyfilename);

441

549

}

442

550

443

551

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

552

(mc->cred, pubkeyfilename, seckeyfilename,

445

553

GNUTLS_OPENPGP_FMT_BASE64);

446

554

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

555

fprintf_plus(stderr,

556

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

557

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

558

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

559

safer_gnutls_strerror(ret));

452

560

goto globalfail;

453

561

}

454

562

455

563

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

457

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

460

goto globalfail;

461

}

462

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

463

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

466

goto globalfail;

467

}

468

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

564

ret = gnutls_dh_params_init(&mc->dh_params);

565

if(ret != GNUTLS_E_SUCCESS){

566

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

567

" initialization: %s\n",

568

safer_gnutls_strerror(ret));

569

goto globalfail;

570

}

571

/* If a Diffie-Hellman parameters file was given, try to use it */

572

if(dhparamsfilename != NULL){

573

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

574

do {

575

int dhpfile = open(dhparamsfilename, O_RDONLY);

576

if(dhpfile == -1){

577

perror_plus("open");

578

dhparamsfilename = NULL;

579

break;

580

}

581

size_t params_capacity = 0;

582

while(true){

583

params_capacity = incbuffer((char **)&params.data,

584

(size_t)params.size,

585

(size_t)params_capacity);

586

if(params_capacity == 0){

587

perror_plus("incbuffer");

588

free(params.data);

589

params.data = NULL;

590

dhparamsfilename = NULL;

591

break;

592

}

593

ssize_t bytes_read = read(dhpfile,

594

params.data + params.size,

595

BUFFER_SIZE);

596

/* EOF */

597

if(bytes_read == 0){

598

break;

599

}

600

/* check bytes_read for failure */

601

if(bytes_read < 0){

602

perror_plus("read");

603

free(params.data);

604

params.data = NULL;

605

dhparamsfilename = NULL;

606

break;

607

}

608

params.size += (unsigned int)bytes_read;

609

}

610

if(params.data == NULL){

611

dhparamsfilename = NULL;

612

}

613

if(dhparamsfilename == NULL){

614

break;

615

}

616

ret = gnutls_dh_params_import_pkcs3(mc->dh_params, &params,

617

GNUTLS_X509_FMT_PEM);

618

if(ret != GNUTLS_E_SUCCESS){

619

fprintf_plus(stderr, "Failed to parse DH parameters in file"

620

" \"%s\": %s\n", dhparamsfilename,

621

safer_gnutls_strerror(ret));

622

dhparamsfilename = NULL;

623

}

624

} while(false);

625

}

626

if(dhparamsfilename == NULL){

627

if(mc->dh_bits == 0){

628

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

629

/* Try to read the private key file */

630

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

631

do {

632

int secfile = open(seckeyfilename, O_RDONLY);

633

if(secfile == -1){

634

perror_plus("open");

635

break;

636

}

637

size_t buffer_capacity = 0;

638

while(true){

639

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

640

(size_t)buffer.size,

641

(size_t)buffer_capacity);

642

if(buffer_capacity == 0){

643

perror_plus("incbuffer");

644

free(buffer.data);

645

buffer.data = NULL;

646

break;

647

}

648

ssize_t bytes_read = read(secfile,

649

buffer.data + buffer.size,

650

BUFFER_SIZE);

651

/* EOF */

652

if(bytes_read == 0){

653

break;

654

}

655

/* check bytes_read for failure */

656

if(bytes_read < 0){

657

perror_plus("read");

658

free(buffer.data);

659

buffer.data = NULL;

660

break;

661

}

662

buffer.size += (unsigned int)bytes_read;

663

}

664

close(secfile);

665

} while(false);

666

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

667

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

668

if(buffer.data != NULL){

669

{

670

gnutls_openpgp_privkey_t privkey = NULL;

671

ret = gnutls_openpgp_privkey_init(&privkey);

672

if(ret != GNUTLS_E_SUCCESS){

673

fprintf_plus(stderr, "Error initializing OpenPGP key"

674

" structure: %s",

675

safer_gnutls_strerror(ret));

676

free(buffer.data);

677

buffer.data = NULL;

678

} else {

679

ret = gnutls_openpgp_privkey_import

680

(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);

681

if(ret != GNUTLS_E_SUCCESS){

682

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

683

safer_gnutls_strerror(ret));

684

privkey = NULL;

685

}

686

free(buffer.data);

687

buffer.data = NULL;

688

if(privkey != NULL){

689

/* Use private key to suggest an appropriate

690

sec_param */

691

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

692

gnutls_openpgp_privkey_deinit(privkey);

693

if(debug){

694

fprintf_plus(stderr, "This OpenPGP key implies using"

695

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

696

safe_string(gnutls_sec_param_get_name

697

(sec_param)));

698

}

699

}

700

}

701

}

702

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

703

/* Err on the side of caution */

704

sec_param = GNUTLS_SEC_PARAM_ULTRA;

705

if(debug){

706

fprintf_plus(stderr, "Falling back to security parameter"

707

" \"%s\"\n",

708

safe_string(gnutls_sec_param_get_name

709

(sec_param)));

710

}

711

}

712

}

713

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

714

if(uret != 0){

715

mc->dh_bits = uret;

716

if(debug){

717

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

718

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

719

safe_string(gnutls_sec_param_get_name

720

(sec_param)),

721

mc->dh_bits);

722

}

723

} else {

724

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

725

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

726

safe_string(gnutls_sec_param_get_name

727

(sec_param)),

728

safer_gnutls_strerror(ret));

729

goto globalfail;

730

}

731

} else if(debug){

732

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

733

mc->dh_bits);

734

}

735

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

736

if(ret != GNUTLS_E_SUCCESS){

737

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

738

" bits): %s\n", mc->dh_bits,

739

safer_gnutls_strerror(ret));

740

goto globalfail;

741

}

742

}

743

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

470

744

471

745

return 0;

472

746

473

747

globalfail:

474

748

475

gnutls_certificate_free_credentials(mc.cred);

476

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

749

gnutls_certificate_free_credentials(mc->cred);

750

gnutls_dh_params_deinit(mc->dh_params);

478

751

return -1;

479

752

}

480

753

481

static int init_gnutls_session(gnutls_session_t *session){

754

__attribute__((nonnull, warn_unused_result))

755

static int init_gnutls_session(gnutls_session_t *session,

756

mandos_context *mc){

482

757

int ret;

483

758

/* GnuTLS session creation */

484

759

do {

488

763

}

489

764

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

490

765

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

766

fprintf_plus(stderr,

767

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

768

safer_gnutls_strerror(ret));

493

769

}

494

770

495

771

{

496

772

const char *err;

497

773

do {

498

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

774

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

499

775

if(quit_now){

500

776

gnutls_deinit(*session);

501

777

return -1;

502

778

}

503

779

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

504

780

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

781

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

782

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

783

safer_gnutls_strerror(ret));

508

784

gnutls_deinit(*session);

509

785

return -1;

510

786

}

512

788

513

789

do {

514

790

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

791

mc->cred);

516

792

if(quit_now){

517

793

gnutls_deinit(*session);

518

794

return -1;

519

795

}

520

796

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

521

797

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

798

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

799

safer_gnutls_strerror(ret));

524

800

gnutls_deinit(*session);

525

801

return -1;

526

802

}

528

804

/* ignore client certificate if any. */

529

805

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

806

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

532

533

807

return 0;

534

808

}

535

809

537

811

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

538

812

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

539

813

814

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

815

__attribute__((warn_unused_result))

816

error_t raise_privileges(void){

817

error_t old_errno = errno;

818

error_t ret_errno = 0;

819

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

820

ret_errno = errno;

821

}

822

errno = old_errno;

823

return ret_errno;

824

}

825

826

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

827

__attribute__((warn_unused_result))

828

error_t raise_privileges_permanently(void){

829

error_t old_errno = errno;

830

error_t ret_errno = raise_privileges();

831

if(ret_errno != 0){

832

errno = old_errno;

833

return ret_errno;

834

}

835

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

836

ret_errno = errno;

837

}

838

errno = old_errno;

839

return ret_errno;

840

}

841

842

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

843

__attribute__((warn_unused_result))

844

error_t lower_privileges(void){

845

error_t old_errno = errno;

846

error_t ret_errno = 0;

847

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

848

ret_errno = errno;

849

}

850

errno = old_errno;

851

return ret_errno;

852

}

853

854

/* Lower privileges permanently */

855

__attribute__((warn_unused_result))

856

error_t lower_privileges_permanently(void){

857

error_t old_errno = errno;

858

error_t ret_errno = 0;

859

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

860

ret_errno = errno;

861

}

862

errno = old_errno;

863

return ret_errno;

864

}

865

866

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

867

__attribute__((nonnull, warn_unused_result))

868

static bool add_delete_local_route(const bool add,

869

const char *address,

870

AvahiIfIndex if_index){

871

int ret;

872

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

873

char add_arg[] = "add";

874

char delete_arg[] = "delete";

875

char debug_flag[] = "--debug";

876

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

877

if(pluginhelperdir == NULL){

878

if(debug){

879

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

880

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

881

}

882

return false;

883

}

884

885

char interface[IF_NAMESIZE];

886

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

887

perror_plus("if_indextoname");

888

return false;

889

}

890

891

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

892

if(devnull == -1){

893

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

894

return false;

895

}

896

pid_t pid = fork();

897

if(pid == 0){

898

/* Child */

899

/* Raise privileges */

900

errno = raise_privileges_permanently();

901

if(errno != 0){

902

perror_plus("Failed to raise privileges");

903

/* _exit(EX_NOPERM); */

904

} else {

905

/* Set group */

906

errno = 0;

907

ret = setgid(0);

908

if(ret == -1){

909

perror_plus("setgid");

910

_exit(EX_NOPERM);

911

}

912

/* Reset supplementary groups */

913

errno = 0;

914

ret = setgroups(0, NULL);

915

if(ret == -1){

916

perror_plus("setgroups");

917

_exit(EX_NOPERM);

918

}

919

}

920

ret = dup2(devnull, STDIN_FILENO);

921

if(ret == -1){

922

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

923

_exit(EX_OSERR);

924

}

925

ret = close(devnull);

926

if(ret == -1){

927

perror_plus("close");

928

_exit(EX_OSERR);

929

}

930

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

931

if(ret == -1){

932

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

933

_exit(EX_OSERR);

934

}

935

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

936

O_RDONLY

937

| O_DIRECTORY

938

| O_PATH

939

| O_CLOEXEC));

940

if(helperdir_fd == -1){

941

perror_plus("open");

942

_exit(EX_UNAVAILABLE);

943

}

944

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

945

helper, O_RDONLY));

946

if(helper_fd == -1){

947

perror_plus("openat");

948

close(helperdir_fd);

949

_exit(EX_UNAVAILABLE);

950

}

951

close(helperdir_fd);

952

#ifdef __GNUC__

953

#pragma GCC diagnostic push

954

#pragma GCC diagnostic ignored "-Wcast-qual"

955

#endif

956

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

957

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

958

interface, debug ? debug_flag : NULL, NULL },

959

environ) == -1){

960

#ifdef __GNUC__

961

#pragma GCC diagnostic pop

962

#endif

963

perror_plus("fexecve");

964

_exit(EXIT_FAILURE);

965

}

966

}

967

if(pid == -1){

968

perror_plus("fork");

969

return false;

970

}

971

int status;

972

pid_t pret = -1;

973

errno = 0;

974

do {

975

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

976

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

977

int errno_raising = 0;

978

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

979

errno_raising = errno;

980

perror_plus("Failed to raise privileges in order to"

981

" kill helper program");

982

}

983

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

984

perror_plus("kill");

985

}

986

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

987

perror_plus("Failed to lower privileges after killing"

988

" helper program");

989

}

990

return false;

991

}

992

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

993

if(pret == -1){

994

perror_plus("waitpid");

995

return false;

996

}

997

if(WIFEXITED(status)){

998

if(WEXITSTATUS(status) != 0){

999

fprintf_plus(stderr, "Error: iprouteadddel exited"

1000

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

1001

return false;

1002

}

1003

return true;

1004

}

1005

if(WIFSIGNALED(status)){

1006

fprintf_plus(stderr, "Error: iprouteadddel died by"

1007

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

1008

return false;

1009

}

1010

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

1011

return false;

1012

}

1013

1014

__attribute__((nonnull, warn_unused_result))

1015

static bool add_local_route(const char *address,

1016

AvahiIfIndex if_index){

1017

if(debug){

1018

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

1019

}

1020

return add_delete_local_route(true, address, if_index);

1021

}

1022

1023

__attribute__((nonnull, warn_unused_result))

1024

static bool delete_local_route(const char *address,

1025

AvahiIfIndex if_index){

1026

if(debug){

1027

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

1028

}

1029

return add_delete_local_route(false, address, if_index);

1030

}

1031

540

1032

/* Called when a Mandos server is found */

541

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

1033

__attribute__((nonnull, warn_unused_result))

1034

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

542

1035

AvahiIfIndex if_index,

543

int af){

1036

int af, mandos_context *mc){

544

1037

int ret, tcp_sd = -1;

545

1038

ssize_t sret;

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

1039

struct sockaddr_storage to;

550

1040

char *buffer = NULL;

551

1041

char *decrypted_buffer = NULL;

552

1042

size_t buffer_length = 0;

555

1045

int retval = -1;

556

1046

gnutls_session_t session;

557

1047

int pf; /* Protocol family */

1048

bool route_added = false;

558

1049

559

1050

errno = 0;

560

1051

571

1062

pf = PF_INET;

572

1063

break;

573

1064

default:

574

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

1065

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

575

1066

errno = EINVAL;

576

1067

return -1;

577

1068

}

578

1069

579

ret = init_gnutls_session(&session);

1070

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

1071

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

1072

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

1073

bool match = false;

1074

{

1075

char *interface = NULL;

1076

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

1077

interface))){

1078

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

1079

match = true;

1080

break;

1081

}

1082

}

1083

}

1084

if(not match){

1085

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

1086

connect to the server */

1087

if(debug){

1088

char interface[IF_NAMESIZE];

1089

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

1090

perror_plus("if_indextoname");

1091

} else {

1092

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

1093

" \"%s\"\n",

1094

if_indextoname((unsigned int)if_index,

1095

interface));

1096

}

1097

}

1098

return -1;

1099

}

1100

}

1101

1102

ret = init_gnutls_session(&session, mc);

580

1103

if(ret != 0){

581

1104

return -1;

582

1105

}

583

1106

584

1107

if(debug){

585

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

586

"\n", ip, port);

1108

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

1109

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

587

1110

}

588

1111

589

tcp_sd = socket(pf, SOCK_STREAM, 0);

1112

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

590

1113

if(tcp_sd < 0){

591

1114

int e = errno;

592

perror("socket");

1115

perror_plus("socket");

593

1116

errno = e;

594

1117

goto mandos_end;

595

1118

}

599

1122

goto mandos_end;

600

1123

}

601

1124

602

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

603

1125

if(af == AF_INET6){

604

to.in6.sin6_family = (sa_family_t)af;

605

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

1126

struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;

1127

*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };

1128

ret = inet_pton(af, ip, &to6->sin6_addr);

606

1129

} else { /* IPv4 */

607

to.in.sin_family = (sa_family_t)af;

608

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

1130

struct sockaddr_in *to4 = (struct sockaddr_in *)&to;

1131

*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };

1132

ret = inet_pton(af, ip, &to4->sin_addr);

609

1133

}

610

1134

if(ret < 0 ){

611

1135

int e = errno;

612

perror("inet_pton");

1136

perror_plus("inet_pton");

613

1137

errno = e;

614

1138

goto mandos_end;

615

1139

}

616

1140

if(ret == 0){

617

1141

int e = errno;

618

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

1142

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

619

1143

errno = e;

620

1144

goto mandos_end;

621

1145

}

622

1146

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

1147

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

1148

if(IN6_IS_ADDR_LINKLOCAL

1149

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

630

1150

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

1151

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

1152

" incomplete without a network interface\n");

633

1153

errno = EINVAL;

634

1154

goto mandos_end;

635

1155

}

636

1156

/* Set the network interface number as scope */

637

to.in6.sin6_scope_id = (uint32_t)if_index;

1157

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

638

1158

}

639

1159

} else {

640

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

641

-Wconversion and

642

-Wunreachable-code */

1160

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

643

1161

}

644

1162

645

1163

if(quit_now){

651

1169

if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){

652

1170

char interface[IF_NAMESIZE];

653

1171

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

654

perror("if_indextoname");

1172

perror_plus("if_indextoname");

655

1173

} else {

656

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

657

ip, interface, port);

1174

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

1175

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

658

1176

}

659

1177

} else {

660

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

661

port);

1178

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

1179

ip, (uintmax_t)port);

662

1180

}

663

1181

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

1182

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

665

const char *pcret;

666

if(af == AF_INET6){

667

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

668

sizeof(addrstr));

669

} else {

670

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

671

sizeof(addrstr));

672

}

673

if(pcret == NULL){

674

perror("inet_ntop");

675

} else {

676

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

677

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

678

}

679

}

680

}

681

682

if(quit_now){

683

errno = EINTR;

684

goto mandos_end;

685

}

686

687

if(af == AF_INET6){

688

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

689

} else {

690

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

691

}

692

if(ret < 0){

693

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

694

int e = errno;

695

perror("connect");

696

errno = e;

697

}

698

goto mandos_end;

699

}

700

701

if(quit_now){

702

errno = EINTR;

703

goto mandos_end;

1183

if(af == AF_INET6){

1184

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

1185

sizeof(struct sockaddr_in6),

1186

addrstr, sizeof(addrstr), NULL, 0,

1187

NI_NUMERICHOST);

1188

} else {

1189

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

1190

sizeof(struct sockaddr_in),

1191

addrstr, sizeof(addrstr), NULL, 0,

1192

NI_NUMERICHOST);

1193

}

1194

if(ret == EAI_SYSTEM){

1195

perror_plus("getnameinfo");

1196

} else if(ret != 0) {

1197

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

1198

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

1199

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

1200

}

1201

}

1202

1203

if(quit_now){

1204

errno = EINTR;

1205

goto mandos_end;

1206

}

1207

1208

while(true){

1209

if(af == AF_INET6){

1210

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

1211

sizeof(struct sockaddr_in6));

1212

} else {

1213

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

1214

sizeof(struct sockaddr_in));

1215

}

1216

if(ret < 0){

1217

if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))

1218

and if_index != AVAHI_IF_UNSPEC

1219

and connect_to == NULL

1220

and not route_added and

1221

((af == AF_INET6 and not

1222

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1223

&to)->sin6_addr)))

1224

or (af == AF_INET and

1225

/* Not a a IPv4LL address */

1226

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

1227

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

1228

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

1229

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

1230

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

1231

connect to a Mandos server announced by Avahi on a server

1232

host with a global address. Work around this by retrying

1233

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

1234

1235

Avahi bug reference:

1236

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

1237

https://bugs.debian.org/587961

1238

*/

1239

if(debug){

1240

fprintf_plus(stderr, "Mandos server unreachable, trying"

1241

" direct route\n");

1242

}

1243

int e = errno;

1244

route_added = add_local_route(ip, if_index);

1245

if(route_added){

1246

continue;

1247

}

1248

errno = e;

1249

}

1250

if(errno != ECONNREFUSED or debug){

1251

int e = errno;

1252

perror_plus("connect");

1253

errno = e;

1254

}

1255

goto mandos_end;

1256

}

1257

1258

if(quit_now){

1259

errno = EINTR;

1260

goto mandos_end;

1261

}

1262

break;

704

1263

}

705

1264

706

1265

const char *out = mandos_protocol_version;

708

1267

while(true){

709

1268

size_t out_size = strlen(out);

710

1269

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

711

out_size - written));

1270

out_size - written));

712

1271

if(ret == -1){

713

1272

int e = errno;

714

perror("write");

1273

perror_plus("write");

715

1274

errno = e;

716

1275

goto mandos_end;

717

1276

}

734

1293

}

735

1294

736

1295

if(debug){

737

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

1296

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

738

1297

}

739

1298

740

1299

if(quit_now){

742

1301

goto mandos_end;

743

1302

}

744

1303

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1304

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

1305

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

1306

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

1307

gnutls_transport_set_ptr(session,

1308

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

1309

747

1310

if(quit_now){

748

1311

errno = EINTR;

759

1322

760

1323

if(ret != GNUTLS_E_SUCCESS){

761

1324

if(debug){

762

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

1325

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

763

1326

gnutls_perror(ret);

764

1327

}

765

1328

errno = EPROTO;

769

1332

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

770

1333

771

1334

if(debug){

772

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

773

ip);

1335

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1336

" %s\n", ip);

774

1337

}

775

1338

776

1339

while(true){

781

1344

}

782

1345

783

1346

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

1347

buffer_capacity);

785

1348

if(buffer_capacity == 0){

786

1349

int e = errno;

787

perror("incbuffer");

1350

perror_plus("incbuffer");

788

1351

errno = e;

789

1352

goto mandos_end;

790

1353

}

814

1377

}

815

1378

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

816

1379

if(ret < 0){

817

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

1380

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

1381

"***\n");

818

1382

gnutls_perror(ret);

819

1383

errno = EPROTO;

820

1384

goto mandos_end;

821

1385

}

822

1386

break;

823

1387

default:

824

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

825

" encrypted session with Mandos server\n");

1388

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

1389

" encrypted session with Mandos server\n");

826

1390

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

1391

errno = EIO;

828

1392

goto mandos_end;

833

1397

}

834

1398

835

1399

if(debug){

836

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

1400

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

837

1401

}

838

1402

839

1403

if(quit_now){

851

1415

852

1416

if(buffer_length > 0){

853

1417

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

856

&decrypted_buffer);

1418

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1419

&decrypted_buffer, mc);

857

1420

if(decrypted_buffer_size >= 0){

858

1421

859

1422

written = 0;

869

1432

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

870

1433

int e = errno;

871

1434

if(debug){

872

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

873

strerror(errno));

1435

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

1436

strerror(errno));

874

1437

}

875

1438

errno = e;

876

1439

goto mandos_end;

885

1448

886

1449

mandos_end:

887

1450

{

1451

if(route_added){

1452

if(not delete_local_route(ip, if_index)){

1453

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

1454

" interface %d", ip, if_index);

1455

}

1456

}

888

1457

int e = errno;

889

1458

free(decrypted_buffer);

890

1459

free(buffer);

891

1460

if(tcp_sd >= 0){

892

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

1461

ret = close(tcp_sd);

893

1462

}

894

1463

if(ret == -1){

895

1464

if(e == 0){

896

1465

e = errno;

897

1466

}

898

perror("close");

1467

perror_plus("close");

899

1468

}

900

1469

gnutls_deinit(session);

1470

errno = e;

901

1471

if(quit_now){

902

e = EINTR;

1472

errno = EINTR;

903

1473

retval = -1;

904

1474

}

905

errno = e;

906

1475

}

907

1476

return retval;

908

1477

}

909

1478

1479

__attribute__((nonnull))

910

1480

static void resolve_callback(AvahiSServiceResolver *r,

911

1481

AvahiIfIndex interface,

912

1482

AvahiProtocol proto,

920

1490

AVAHI_GCC_UNUSED AvahiStringList *txt,

921

1491

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

1492

flags,

923

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1493

void *mc){

1494

if(r == NULL){

1495

return;

1496

}

925

1497

926

1498

/* Called whenever a service has been resolved successfully or

927

1499

timed out */

928

1500

929

1501

if(quit_now){

1502

avahi_s_service_resolver_free(r);

930

1503

return;

931

1504

}

932

1505

933

1506

switch(event){

934

1507

default:

935

1508

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1509

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

1510

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

1511

domain,

1512

avahi_strerror(avahi_server_errno

1513

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

939

1514

break;

940

1515

941

1516

case AVAHI_RESOLVER_FOUND:

943

1518

char ip[AVAHI_ADDRESS_STR_MAX];

944

1519

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

945

1520

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1521

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

1522

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

1523

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

949

1524

}

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

1525

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

1526

interface,

1527

avahi_proto_to_af(proto),

1528

mc);

952

1529

if(ret == 0){

953

avahi_simple_poll_quit(mc.simple_poll);

1530

avahi_simple_poll_quit(simple_poll);

1531

} else {

1532

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

1533

avahi_proto_to_af(proto),

1534

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

1535

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

1536

" list\n", name);

1537

}

954

1538

}

955

1539

}

956

1540

}

966

1550

const char *domain,

967

1551

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

1552

flags,

969

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1553

void *mc){

1554

if(b == NULL){

1555

return;

1556

}

971

1557

972

1558

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

973

1559

is removed from the LAN */

980

1566

default:

981

1567

case AVAHI_BROWSER_FAILURE:

982

1568

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

1569

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

1570

avahi_strerror(avahi_server_errno

1571

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

1572

avahi_simple_poll_quit(simple_poll);

986

1573

return;

987

1574

988

1575

case AVAHI_BROWSER_NEW:

991

1578

the callback function is called the Avahi server will free the

992

1579

resolver for us. */

993

1580

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

997

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

998

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

1581

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

1582

interface, protocol, name, type,

1583

domain, protocol, 0,

1584

resolve_callback, mc) == NULL)

1585

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

1586

" %s\n", name,

1587

avahi_strerror(avahi_server_errno

1588

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

999

1589

break;

1000

1590

1001

1591

case AVAHI_BROWSER_REMOVE:

1004

1594

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1595

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1596

if(debug){

1007

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

1597

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

1598

" searching...\n");

1008

1599

}

1009

1600

break;

1010

1601

}

1011

1602

}

1012

1603

1013

/* stop main loop after sigterm has been called */

1604

/* Signal handler that stops main loop after SIGTERM */

1014

1605

static void handle_sigterm(int sig){

1015

1606

if(quit_now){

1016

1607

return;

1018

1609

quit_now = 1;

1019

1610

signal_received = sig;

1020

1611

int old_errno = errno;

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1612

/* set main loop to exit */

1613

if(simple_poll != NULL){

1614

avahi_simple_poll_quit(simple_poll);

1023

1615

}

1024

1616

errno = old_errno;

1025

1617

}

1026

1618

1619

__attribute__((nonnull, warn_unused_result))

1620

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

1621

int ret;

1622

error_t ret_errno;

1623

1624

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

1625

if(s < 0){

1626

ret_errno = errno;

1627

perror_plus("socket");

1628

errno = ret_errno;

1629

return false;

1630

}

1631

strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);

1632

ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */

1633

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1634

if(ret == -1){

1635

if(debug){

1636

ret_errno = errno;

1637

perror_plus("ioctl SIOCGIFFLAGS");

1638

errno = ret_errno;

1639

}

1640

return false;

1641

}

1642

return true;

1643

}

1644

1645

__attribute__((nonnull, warn_unused_result))

1646

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

1647

1648

/* Reject the loopback device */

1649

if(ifr->ifr_flags & IFF_LOOPBACK){

1650

if(debug){

1651

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

1652

ifname);

1653

}

1654

return false;

1655

}

1656

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

1657

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

1658

if(debug){

1659

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

1660

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

1661

}

1662

return true;

1663

}

1664

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

1665

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

1666

if(debug){

1667

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1668

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

1669

}

1670

return false;

1671

}

1672

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

1673

if(ifr->ifr_flags & IFF_NOARP){

1674

if(debug){

1675

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

1676

ifname);

1677

}

1678

return false;

1679

}

1680

1681

/* Accept this device */

1682

if(debug){

1683

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

1684

}

1685

return true;

1686

}

1687

1027

1688

/*

1028

1689

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

1029

1690

* corresponds to an acceptable network device.

1030

1691

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

1031

1692

*/

1693

__attribute__((nonnull, warn_unused_result))

1032

1694

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

1695

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

1042

1696

return 0;

1043

1697

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1698

1699

struct ifreq ifr;

1700

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

1701

if(debug){

1702

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

1703

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

1704

}

1705

return 0;

1706

}

1707

1708

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

1709

return 0;

1710

}

1711

return 1;

1712

}

1713

1714

/*

1715

* This function determines if a network interface is up.

1716

*/

1717

__attribute__((nonnull, warn_unused_result))

1718

bool interface_is_up(const char *interface){

1719

struct ifreq ifr;

1720

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

1721

if(debug){

1722

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

1723

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

1724

}

1725

return false;

1726

}

1727

1728

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

1729

}

1730

1731

/*

1732

* This function determines if a network interface is running

1733

*/

1734

__attribute__((nonnull, warn_unused_result))

1735

bool interface_is_running(const char *interface){

1736

struct ifreq ifr;

1737

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

1738

if(debug){

1739

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

1740

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

1741

}

1742

return false;

1743

}

1744

1745

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

1746

}

1747

1748

__attribute__((nonnull, pure, warn_unused_result))

1749

int notdotentries(const struct dirent *direntry){

1750

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

1751

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

1752

and (direntry->d_name[1] == '\0'

1753

or (direntry->d_name[1] == '.'

1754

and direntry->d_name[2] == '\0'))){

1755

return 0;

1756

}

1757

return 1;

1758

}

1759

1760

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

1761

__attribute__((nonnull, warn_unused_result))

1762

int runnable_hook(const struct dirent *direntry){

1763

int ret;

1764

size_t sret;

1765

struct stat st;

1766

1767

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

1768

/* Empty name? */

1769

return 0;

1770

}

1771

1772

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

1773

"abcdefghijklmnopqrstuvwxyz"

1774

"0123456789"

1775

"_.-");

1776

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

1777

/* Contains non-allowed characters */

1778

if(debug){

1779

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

1780

direntry->d_name);

1781

}

1782

return 0;

1783

}

1784

1785

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

1786

if(ret == -1){

1787

if(debug){

1788

perror_plus("Could not stat hook");

1789

}

1790

return 0;

1791

}

1792

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

1793

/* Not a regular file */

1794

if(debug){

1795

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

1796

direntry->d_name);

1797

}

1798

return 0;

1799

}

1800

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

1801

/* Not executable */

1802

if(debug){

1803

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

1804

direntry->d_name);

1805

}

1806

return 0;

1807

}

1808

if(debug){

1809

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

1810

direntry->d_name);

1811

}

1812

return 1;

1813

}

1814

1815

__attribute__((nonnull, warn_unused_result))

1816

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1817

mandos_context *mc){

1818

int ret;

1819

struct timespec now;

1820

struct timespec waited_time;

1821

intmax_t block_time;

1822

1823

while(true){

1824

if(mc->current_server == NULL){

1825

if(debug){

1826

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

1827

" No timeout!\n");

1828

}

1829

ret = avahi_simple_poll_iterate(s, -1);

1830

} else {

1831

if(debug){

1832

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

1833

" it, or wait\n");

1834

}

1835

/* the current time */

1836

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1837

if(ret == -1){

1838

perror_plus("clock_gettime");

1839

return -1;

1840

}

1841

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

1842

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

1843

waited_time.tv_sec = (now.tv_sec

1844

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

1845

waited_time.tv_nsec = (now.tv_nsec

1846

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

1847

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

1848

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

1849

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

1850

block_time = ((retry_interval

1851

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

1852

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

1853

1854

if(debug){

1855

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

1856

block_time);

1857

}

1858

1859

if(block_time <= 0){

1860

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

1861

mc->current_server->port,

1862

mc->current_server->if_index,

1863

mc->current_server->af, mc);

1864

if(ret == 0){

1865

avahi_simple_poll_quit(s);

1866

return 0;

1867

}

1868

ret = clock_gettime(CLOCK_MONOTONIC,

1869

&mc->current_server->last_seen);

1870

if(ret == -1){

1871

perror_plus("clock_gettime");

1872

return -1;

1873

}

1874

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

1875

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

1876

servers, but don't block */

1877

}

1878

1879

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

1880

}

1881

if(ret != 0){

1882

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

1883

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

1884

}

1885

}

1886

}

1887

}

1888

1889

__attribute__((nonnull))

1890

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

1891

const float delay){

1892

struct dirent **direntries = NULL;

1893

if(hookdir_fd == -1){

1894

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1895

| O_CLOEXEC);

1896

if(hookdir_fd == -1){

1897

if(errno == ENOENT){

1898

if(debug){

1899

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

1900

" found\n", hookdir);

1901

}

1902

} else {

1903

perror_plus("open");

1904

}

1905

return;

1906

}

1907

}

1908

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

1909

runnable_hook, alphasort);

1910

if(numhooks == -1){

1911

perror_plus("scandir");

1912

return;

1913

}

1914

struct dirent *direntry;

1915

int ret;

1916

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

1917

if(devnull == -1){

1918

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

1919

return;

1920

}

1921

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

1922

direntry = direntries[i];

1923

if(debug){

1924

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

1925

direntry->d_name);

1926

}

1927

pid_t hook_pid = fork();

1928

if(hook_pid == 0){

1929

/* Child */

1930

/* Raise privileges */

1931

errno = raise_privileges_permanently();

1932

if(errno != 0){

1933

perror_plus("Failed to raise privileges");

1934

_exit(EX_NOPERM);

1935

}

1936

/* Set group */

1937

errno = 0;

1938

ret = setgid(0);

1939

if(ret == -1){

1940

perror_plus("setgid");

1941

_exit(EX_NOPERM);

1942

}

1943

/* Reset supplementary groups */

1944

errno = 0;

1945

ret = setgroups(0, NULL);

1946

if(ret == -1){

1947

perror_plus("setgroups");

1948

_exit(EX_NOPERM);

1949

}

1950

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

1951

if(ret == -1){

1952

perror_plus("setenv");

1953

_exit(EX_OSERR);

1954

}

1955

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

1956

if(ret == -1){

1957

perror_plus("setenv");

1958

_exit(EX_OSERR);

1959

}

1960

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

1961

if(ret == -1){

1962

perror_plus("setenv");

1963

_exit(EX_OSERR);

1964

}

1965

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

1966

if(ret == -1){

1967

perror_plus("setenv");

1968

_exit(EX_OSERR);

1969

}

1970

char *delaystring;

1971

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

1972

if(ret == -1){

1973

perror_plus("asprintf");

1974

_exit(EX_OSERR);

1975

}

1976

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

1977

if(ret == -1){

1978

free(delaystring);

1979

perror_plus("setenv");

1980

_exit(EX_OSERR);

1981

}

1982

free(delaystring);

1983

if(connect_to != NULL){

1984

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

1985

if(ret == -1){

1986

perror_plus("setenv");

1987

_exit(EX_OSERR);

1988

}

1989

}

1990

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

1991

direntry->d_name,

1992

O_RDONLY));

1993

if(hook_fd == -1){

1994

perror_plus("openat");

1995

_exit(EXIT_FAILURE);

1996

}

1997

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

1998

perror_plus("close");

1999

_exit(EXIT_FAILURE);

2000

}

2001

ret = dup2(devnull, STDIN_FILENO);

2002

if(ret == -1){

2003

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

2004

_exit(EX_OSERR);

2005

}

2006

ret = close(devnull);

2007

if(ret == -1){

2008

perror_plus("close");

2009

_exit(EX_OSERR);

2010

}

2011

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2012

if(ret == -1){

2013

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

2014

_exit(EX_OSERR);

2015

}

2016

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

2017

environ) == -1){

2018

perror_plus("fexecve");

2019

_exit(EXIT_FAILURE);

2020

}

2021

} else {

2022

if(hook_pid == -1){

2023

perror_plus("fork");

2024

free(direntry);

2025

continue;

2026

}

2027

int status;

2028

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

2029

perror_plus("waitpid");

2030

free(direntry);

2031

continue;

2032

}

2033

if(WIFEXITED(status)){

2034

if(WEXITSTATUS(status) != 0){

2035

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

2036

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

2037

WEXITSTATUS(status));

2038

free(direntry);

2039

continue;

2040

}

2041

} else if(WIFSIGNALED(status)){

2042

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

2043

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

2044

WTERMSIG(status));

2045

free(direntry);

2046

continue;

2047

} else {

2048

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

2049

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

2050

free(direntry);

2051

continue;

2052

}

2053

}

2054

if(debug){

2055

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

2056

direntry->d_name);

2057

}

2058

free(direntry);

2059

}

2060

free(direntries);

2061

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

2062

perror_plus("close");

2063

} else {

2064

hookdir_fd = -1;

2065

}

2066

close(devnull);

2067

}

2068

2069

__attribute__((nonnull, warn_unused_result))

2070

error_t bring_up_interface(const char *const interface,

2071

const float delay){

2072

error_t old_errno = errno;

2073

int ret;

2074

struct ifreq network;

2075

unsigned int if_index = if_nametoindex(interface);

2076

if(if_index == 0){

2077

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

2078

errno = old_errno;

2079

return ENXIO;

2080

}

2081

2082

if(quit_now){

2083

errno = old_errno;

2084

return EINTR;

2085

}

2086

2087

if(not interface_is_up(interface)){

2088

error_t ret_errno = 0, ioctl_errno = 0;

2089

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

2090

ret_errno = errno;

2091

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

2092

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

2093

errno = old_errno;

2094

return ret_errno;

2095

}

2096

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

2097

2098

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

2099

if(sd == -1){

2100

ret_errno = errno;

2101

perror_plus("socket");

2102

errno = old_errno;

2103

return ret_errno;

2104

}

2105

2106

if(quit_now){

2107

ret = close(sd);

2108

if(ret == -1){

2109

perror_plus("close");

2110

}

2111

errno = old_errno;

2112

return EINTR;

2113

}

2114

2115

if(debug){

2116

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

2117

interface);

2118

}

2119

2120

/* Raise privileges */

2121

ret_errno = raise_privileges();

2122

if(ret_errno != 0){

2123

errno = ret_errno;

2124

perror_plus("Failed to raise privileges");

2125

}

2126

2127

#ifdef __linux__

2128

int ret_linux;

2129

bool restore_loglevel = false;

2130

if(ret_errno == 0){

2131

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2132

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

2133

ret_linux = klogctl(8, NULL, 5);

2134

if(ret_linux == -1){

2135

perror_plus("klogctl");

2136

} else {

2137

restore_loglevel = true;

2138

}

2139

}

2140

#endif /* __linux__ */

2141

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

2142

ioctl_errno = errno;

2143

#ifdef __linux__

2144

if(restore_loglevel){

2145

ret_linux = klogctl(7, NULL, 0);

2146

if(ret_linux == -1){

2147

perror_plus("klogctl");

2148

}

2149

}

2150

#endif /* __linux__ */

2151

2152

/* If raise_privileges() succeeded above */

2153

if(ret_errno == 0){

2154

/* Lower privileges */

2155

ret_errno = lower_privileges();

2156

if(ret_errno != 0){

2157

errno = ret_errno;

2158

perror_plus("Failed to lower privileges");

2159

}

2160

}

2161

2162

/* Close the socket */

2163

ret = close(sd);

2164

if(ret == -1){

2165

perror_plus("close");

2166

}

2167

2168

if(ret_setflags == -1){

2169

errno = ioctl_errno;

2170

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2171

errno = old_errno;

2172

return ioctl_errno;

2173

}

2174

} else if(debug){

2175

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

2176

interface);

2177

}

2178

2179

/* Sleep checking until interface is running.

2180

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

2181

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

2182

if(interface_is_running(interface)){

1070

2183

break;

1071

2184

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

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

1100

if(debug){

1101

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

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

2185

struct timespec sleeptime = { .tv_nsec = 250000000 };

2186

ret = nanosleep(&sleeptime, NULL);

2187

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

2188

perror_plus("nanosleep");

2189

}

2190

}

2191

2192

errno = old_errno;

2193

return 0;

2194

}

2195

2196

__attribute__((nonnull, warn_unused_result))

2197

error_t take_down_interface(const char *const interface){

2198

error_t old_errno = errno;

2199

struct ifreq network;

2200

unsigned int if_index = if_nametoindex(interface);

2201

if(if_index == 0){

2202

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

2203

errno = old_errno;

2204

return ENXIO;

2205

}

2206

if(interface_is_up(interface)){

2207

error_t ret_errno = 0, ioctl_errno = 0;

2208

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

2209

ret_errno = errno;

2210

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

2211

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

2212

errno = old_errno;

2213

return ret_errno;

2214

}

2215

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

2216

2217

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

2218

if(sd == -1){

2219

ret_errno = errno;

2220

perror_plus("socket");

2221

errno = old_errno;

2222

return ret_errno;

2223

}

2224

2225

if(debug){

2226

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

2227

interface);

2228

}

2229

2230

/* Raise privileges */

2231

ret_errno = raise_privileges();

2232

if(ret_errno != 0){

2233

errno = ret_errno;

2234

perror_plus("Failed to raise privileges");

2235

}

2236

2237

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

2238

ioctl_errno = errno;

2239

2240

/* If raise_privileges() succeeded above */

2241

if(ret_errno == 0){

2242

/* Lower privileges */

2243

ret_errno = lower_privileges();

2244

if(ret_errno != 0){

2245

errno = ret_errno;

2246

perror_plus("Failed to lower privileges");

2247

}

2248

}

2249

2250

/* Close the socket */

2251

int ret = close(sd);

2252

if(ret == -1){

2253

perror_plus("close");

2254

}

2255

2256

if(ret_setflags == -1){

2257

errno = ioctl_errno;

2258

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2259

errno = old_errno;

2260

return ioctl_errno;

2261

}

2262

} else if(debug){

2263

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

2264

interface);

2265

}

2266

2267

errno = old_errno;

2268

return 0;

1120

2269

}

1121

2270

1122

2271

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

2272

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

2273

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

2274

":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",

2275

.current_server = NULL, .interfaces = NULL,

2276

.interfaces_size = 0 };

1123

2277

AvahiSServiceBrowser *sb = NULL;

1124

int error;

2278

error_t ret_errno;

1125

2279

int ret;

1126

2280

intmax_t tmpmax;

1127

2281

char *tmp;

1128

2282

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

1130

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

1133

uid_t uid;

1134

gid_t gid;

1135

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

1136

bool tempdir_created = false;

2283

char *interfaces_to_take_down = NULL;

2284

size_t interfaces_to_take_down_size = 0;

2285

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

2286

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

2287

char *tempdir = NULL;

1137

2288

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

2289

const char *seckey = PATHDIR "/" SECKEY;

1139

2290

const char *pubkey = PATHDIR "/" PUBKEY;

2291

const char *dh_params_file = NULL;

2292

char *interfaces_hooks = NULL;

1140

2293

1141

2294

bool gnutls_initialized = false;

1142

2295

bool gpgme_initialized = false;

1143

2296

float delay = 2.5f;

2297

double retry_interval = 10; /* 10s between trying a server and

2298

retrying the same server again */

1144

2299

1145

2300

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

2301

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

2307

errno = 0;

1153

2308

ret = setgid(gid);

1154

2309

if(ret == -1){

1155

perror("setgid");

2310

perror_plus("setgid");

1156

2311

}

1157

2312

1158

2313

/* Lower user privileges (temporarily) */

1159

2314

errno = 0;

1160

2315

ret = seteuid(uid);

1161

2316

if(ret == -1){

1162

perror("seteuid");

2317

perror_plus("seteuid");

1163

2318

}

1164

2319

1165

2320

if(quit_now){

1192

2347

.doc = "Bit length of the prime number used in the"

1193

2348

" Diffie-Hellman key exchange",

1194

2349

.group = 2 },

2350

{ .name = "dh-params", .key = 134,

2351

.arg = "FILE",

2352

.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"

2353

" for the Diffie-Hellman key exchange",

2354

.group = 2 },

1195

2355

{ .name = "priority", .key = 130,

1196

2356

.arg = "STRING",

1197

2357

.doc = "GnuTLS priority string for the TLS handshake",

1200

2360

.arg = "SECONDS",

1201

2361

.doc = "Maximum delay to wait for interface startup",

1202

2362

.group = 2 },

2363

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

2364

.arg = "SECONDS",

2365

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

2366

.group = 2 },

2367

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

2368

.arg = "DIR",

2369

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

2370

.group = 2 },

1203

2371

/*

1204

2372

* These reproduce what we would get without ARGP_NO_HELP

1205

2373

*/

1223

2391

connect_to = arg;

1224

2392

break;

1225

2393

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

1226

interface = arg;

2394

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

2395

arg, (int)',');

2396

if(ret_errno != 0){

2397

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

2398

}

1227

2399

break;

1228

2400

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

1229

2401

seckey = arg;

1240

2412

}

1241

2413

mc.dh_bits = (typeof(mc.dh_bits))tmpmax;

1242

2414

break;

2415

case 134: /* --dh-params */

2416

dh_params_file = arg;

2417

break;

1243

2418

case 130: /* --priority */

1244

2419

mc.priority = arg;

1245

2420

break;

1249

2424

if(errno != 0 or tmp == arg or *tmp != '\0'){

1250

2425

argp_error(state, "Bad delay");

1251

2426

}

2427

case 132: /* --retry */

2428

errno = 0;

2429

retry_interval = strtod(arg, &tmp);

2430

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

2431

or (retry_interval * 1000) > INT_MAX

2432

or retry_interval < 0){

2433

argp_error(state, "Bad retry interval");

2434

}

2435

break;

2436

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

2437

hookdir = arg;

1252

2438

break;

1253

2439

/*

1254

2440

* These reproduce what we would get without ARGP_NO_HELP

1261

2447

argp_state_help(state, state->out_stream,

1262

2448

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

2449

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

1264

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

2450

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

1265

2451

exit(argp_err_exit_status);

1266

2452

break;

1267

2453

default:

1282

2468

case ENOMEM:

1283

2469

default:

1284

2470

errno = ret;

1285

perror("argp_parse");

2471

perror_plus("argp_parse");

1286

2472

exitcode = EX_OSERR;

1287

2473

goto end;

1288

2474

case EINVAL:

1291

2477

}

1292

2478

}

1293

2479

2480

{

2481

/* Work around Debian bug #633582:

2482

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

2483

2484

/* Re-raise privileges */

2485

ret_errno = raise_privileges();

2486

if(ret_errno != 0){

2487

errno = ret_errno;

2488

perror_plus("Failed to raise privileges");

2489

} else {

2490

struct stat st;

2491

2492

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

2493

int seckey_fd = open(seckey, O_RDONLY);

2494

if(seckey_fd == -1){

2495

perror_plus("open");

2496

} else {

2497

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

2498

if(ret == -1){

2499

perror_plus("fstat");

2500

} else {

2501

if(S_ISREG(st.st_mode)

2502

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

2503

ret = fchown(seckey_fd, uid, gid);

2504

if(ret == -1){

2505

perror_plus("fchown");

2506

}

2507

}

2508

}

2509

close(seckey_fd);

2510

}

2511

}

2512

2513

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

2514

int pubkey_fd = open(pubkey, O_RDONLY);

2515

if(pubkey_fd == -1){

2516

perror_plus("open");

2517

} else {

2518

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

2519

if(ret == -1){

2520

perror_plus("fstat");

2521

} else {

2522

if(S_ISREG(st.st_mode)

2523

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

2524

ret = fchown(pubkey_fd, uid, gid);

2525

if(ret == -1){

2526

perror_plus("fchown");

2527

}

2528

}

2529

}

2530

close(pubkey_fd);

2531

}

2532

}

2533

2534

if(dh_params_file != NULL

2535

and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){

2536

int dhparams_fd = open(dh_params_file, O_RDONLY);

2537

if(dhparams_fd == -1){

2538

perror_plus("open");

2539

} else {

2540

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

2541

if(ret == -1){

2542

perror_plus("fstat");

2543

} else {

2544

if(S_ISREG(st.st_mode)

2545

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

2546

ret = fchown(dhparams_fd, uid, gid);

2547

if(ret == -1){

2548

perror_plus("fchown");

2549

}

2550

}

2551

}

2552

close(dhparams_fd);

2553

}

2554

}

2555

2556

/* Lower privileges */

2557

ret_errno = lower_privileges();

2558

if(ret_errno != 0){

2559

errno = ret_errno;

2560

perror_plus("Failed to lower privileges");

2561

}

2562

}

2563

}

2564

2565

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

2566

{

2567

char *interface = NULL;

2568

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

2569

interface))){

2570

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

2571

and if_nametoindex(interface) == 0){

2572

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

2573

fprintf_plus(stderr, "Not using nonexisting interface"

2574

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

2575

}

2576

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

2577

interface = NULL;

2578

}

2579

}

2580

}

2581

2582

/* Run network hooks */

2583

{

2584

if(mc.interfaces != NULL){

2585

interfaces_hooks = malloc(mc.interfaces_size);

2586

if(interfaces_hooks == NULL){

2587

perror_plus("malloc");

2588

goto end;

2589

}

2590

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

2591

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

2592

}

2593

run_network_hooks("start", interfaces_hooks != NULL ?

2594

interfaces_hooks : "", delay);

2595

}

2596

1294

2597

if(not debug){

1295

2598

avahi_set_log_function(empty_log);

1296

2599

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1322

2600

1323

2601

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

1324

2602

from the signal handler */

1325

2603

/* Initialize the pseudo-RNG for Avahi */

1326

2604

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

1327

mc.simple_poll = avahi_simple_poll_new();

1328

if(mc.simple_poll == NULL){

1329

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

2605

simple_poll = avahi_simple_poll_new();

2606

if(simple_poll == NULL){

2607

fprintf_plus(stderr,

2608

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

1330

2609

exitcode = EX_UNAVAILABLE;

1331

2610

goto end;

1332

2611

}

1334

2613

sigemptyset(&sigterm_action.sa_mask);

1335

2614

ret = sigaddset(&sigterm_action.sa_mask, SIGINT);

1336

2615

if(ret == -1){

1337

perror("sigaddset");

2616

perror_plus("sigaddset");

1338

2617

exitcode = EX_OSERR;

1339

2618

goto end;

1340

2619

}

1341

2620

ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);

1342

2621

if(ret == -1){

1343

perror("sigaddset");

2622

perror_plus("sigaddset");

1344

2623

exitcode = EX_OSERR;

1345

2624

goto end;

1346

2625

}

1347

2626

ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);

1348

2627

if(ret == -1){

1349

perror("sigaddset");

2628

perror_plus("sigaddset");

1350

2629

exitcode = EX_OSERR;

1351

2630

goto end;

1352

2631

}

1356

2635

*/

1357

2636

ret = sigaction(SIGINT, NULL, &old_sigterm_action);

1358

2637

if(ret == -1){

1359

perror("sigaction");

2638

perror_plus("sigaction");

1360

2639

return EX_OSERR;

1361

2640

}

1362

2641

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

2642

ret = sigaction(SIGINT, &sigterm_action, NULL);

1364

2643

if(ret == -1){

1365

perror("sigaction");

2644

perror_plus("sigaction");

1366

2645

exitcode = EX_OSERR;

1367

2646

goto end;

1368

2647

}

1369

2648

}

1370

2649

ret = sigaction(SIGHUP, NULL, &old_sigterm_action);

1371

2650

if(ret == -1){

1372

perror("sigaction");

2651

perror_plus("sigaction");

1373

2652

return EX_OSERR;

1374

2653

}

1375

2654

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

2655

ret = sigaction(SIGHUP, &sigterm_action, NULL);

1377

2656

if(ret == -1){

1378

perror("sigaction");

2657

perror_plus("sigaction");

1379

2658

exitcode = EX_OSERR;

1380

2659

goto end;

1381

2660

}

1382

2661

}

1383

2662

ret = sigaction(SIGTERM, NULL, &old_sigterm_action);

1384

2663

if(ret == -1){

1385

perror("sigaction");

2664

perror_plus("sigaction");

1386

2665

return EX_OSERR;

1387

2666

}

1388

2667

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

2668

ret = sigaction(SIGTERM, &sigterm_action, NULL);

1390

2669

if(ret == -1){

1391

perror("sigaction");

1392

exitcode = EX_OSERR;

1393

goto end;

1394

}

1395

}

1396

1397

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1417

#ifdef __linux__

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

1420

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

if(ret == -1){

1423

restore_loglevel = false;

1424

perror("klogctl");

1425

}

1426

#endif /* __linux__ */

1427

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

if(sd < 0){

1430

perror("socket");

1431

exitcode = EX_OSERR;

1432

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1446

goto end;

1447

}

1448

strcpy(network.ifr_name, interface);

1449

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

1450

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1452

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1467

goto end;

1468

}

1469

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

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

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

1473

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1477

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

2670

perror_plus("sigaction");

2671

exitcode = EX_OSERR;

2672

goto end;

2673

}

2674

}

2675

2676

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

2677

if(mc.interfaces == NULL){

2678

struct dirent **direntries = NULL;

2679

/* Look for any good interfaces */

2680

ret = scandir(sys_class_net, &direntries, good_interface,

2681

alphasort);

2682

if(ret >= 1){

2683

/* Add all found interfaces to interfaces list */

2684

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

2685

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

2686

direntries[i]->d_name);

2687

if(ret_errno != 0){

2688

errno = ret_errno;

2689

perror_plus("argz_add");

2690

free(direntries[i]);

2691

continue;

2692

}

2693

if(debug){

2694

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

2695

direntries[i]->d_name);

2696

}

2697

free(direntries[i]);

2698

}

2699

free(direntries);

2700

} else {

2701

if(ret == 0){

2702

free(direntries);

2703

}

2704

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

2705

exitcode = EXIT_FAILURE;

2706

goto end;

2707

}

2708

}

2709

2710

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

2711

{

2712

char *interface = NULL;

2713

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

2714

interface))){

2715

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

2716

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

2717

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

2718

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

2719

interface);

2720

interface = NULL;

2721

while((interface = argz_next(mc.interfaces,

2722

mc.interfaces_size, interface))){

2723

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

2724

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

2725

interface);

2726

interface = NULL;

1482

2727

}

1483

2728

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1491

goto end;

1492

}

1493

}

1494

/* sleep checking until interface is running */

1495

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

1496

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

1497

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1499

} else if(network.ifr_flags & IFF_RUNNING){

1500

2729

break;

1501

2730

}

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

ret = nanosleep(&sleeptime, NULL);

1504

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

1505

perror("nanosleep");

1506

}

1507

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1514

}

1515

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

1532

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

2731

bool interface_was_up = interface_is_up(interface);

2732

errno = bring_up_interface(interface, delay);

2733

if(not interface_was_up){

2734

if(errno != 0){

2735

fprintf_plus(stderr, "Failed to bring up interface \"%s\":"

2736

" %s\n", interface, strerror(errno));

2737

} else {

2738

errno = argz_add(&interfaces_to_take_down,

2739

&interfaces_to_take_down_size,

2740

interface);

2741

if(errno != 0){

2742

perror_plus("argz_add");

2743

}

2744

}

2745

}

2746

}

2747

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

2748

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

2749

}

2750

}

2751

2752

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

2753

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

2754

if(debug){

2755

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

2756

mc.interfaces);

2757

}

2758

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

1539

2759

}

1540

2760

1541

2761

if(quit_now){

1542

2762

goto end;

1543

2763

}

1544

2764

1545

ret = init_gnutls_global(pubkey, seckey);

2765

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

1546

2766

if(ret == -1){

1547

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

2767

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

1548

2768

exitcode = EX_UNAVAILABLE;

1549

2769

goto end;

1550

2770

} else {

1555

2775

goto end;

1556

2776

}

1557

2777

1558

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

2778

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

2779

tempdir = mkdtemp(run_tempdir);

2780

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

2781

if(debug){

2782

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

2783

run_tempdir, old_tempdir);

2784

}

2785

tempdir = mkdtemp(old_tempdir);

2786

}

2787

if(tempdir == NULL){

2788

perror_plus("mkdtemp");

1562

2789

goto end;

1563

2790

}

1564

2791

1566

2793

goto end;

1567

2794

}

1568

2795

1569

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

1570

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

2796

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

2797

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

1571

2798

exitcode = EX_UNAVAILABLE;

1572

2799

goto end;

1573

2800

} else {

1582

2809

/* Connect directly, do not use Zeroconf */

1583

2810

/* (Mainly meant for debugging) */

1584

2811

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

2812

1585

2813

if(address == NULL){

1586

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

2814

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

1587

2815

exitcode = EX_USAGE;

1588

2816

goto end;

1589

2817

}

1592

2820

goto end;

1593

2821

}

1594

2822

1595

uint16_t port;

2823

in_port_t port;

1596

2824

errno = 0;

1597

2825

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

1598

2826

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

1599

or tmpmax != (uint16_t)tmpmax){

1600

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

2827

or tmpmax != (in_port_t)tmpmax){

2828

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

1601

2829

exitcode = EX_USAGE;

1602

2830

goto end;

1603

2831

}

1604

2832

1605

2833

if(quit_now){

1606

2834

goto end;

1607

2835

}

1608

2836

1609

port = (uint16_t)tmpmax;

2837

port = (in_port_t)tmpmax;

1610

2838

*address = '\0';

1611

address = connect_to;

1612

2839

/* Colon in address indicates IPv6 */

1613

2840

int af;

1614

if(strchr(address, ':') != NULL){

2841

if(strchr(connect_to, ':') != NULL){

1615

2842

af = AF_INET6;

2843

/* Accept [] around IPv6 address - see RFC 5952 */

2844

if(connect_to[0] == '[' and address[-1] == ']')

2845

{

2846

connect_to++;

2847

address[-1] = '\0';

2848

}

1616

2849

} else {

1617

2850

af = AF_INET;

1618

2851

}

2852

address = connect_to;

1619

2853

1620

2854

if(quit_now){

1621

2855

goto end;

1622

2856

}

1623

2857

1624

2858

while(not quit_now){

1625

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

2859

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

2860

&mc);

1626

2861

if(quit_now or ret == 0){

1627

2862

break;

1628

2863

}

1629

sleep(15);

1630

};

1631

1632

if (not quit_now){

2864

if(debug){

2865

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

2866

(int)retry_interval);

2867

}

2868

sleep((unsigned int)retry_interval);

2869

}

2870

2871

if(not quit_now){

1633

2872

exitcode = EXIT_SUCCESS;

1634

2873

}

1635

2874

1636

2875

goto end;

1637

2876

}

1638

2877

1650

2889

config.publish_domain = 0;

1651

2890

1652

2891

/* Allocate a new server */

1653

mc.server = avahi_server_new(avahi_simple_poll_get

1654

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2892

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2893

&config, NULL, NULL, &ret_errno);

1656

2894

1657

2895

/* Free the Avahi configuration data */

1658

2896

avahi_server_config_free(&config);

1660

2898

1661

2899

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

1662

2900

if(mc.server == NULL){

1663

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

1664

avahi_strerror(error));

2901

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

2902

avahi_strerror(ret_errno));

1665

2903

exitcode = EX_UNAVAILABLE;

1666

2904

goto end;

1667

2905

}

1673

2911

/* Create the Avahi service browser */

1674

2912

sb = avahi_s_service_browser_new(mc.server, if_index,

1675

2913

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

NULL, 0, browse_callback, NULL);

2914

NULL, 0, browse_callback,

2915

(void *)&mc);

1677

2916

if(sb == NULL){

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2917

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

2918

avahi_strerror(avahi_server_errno(mc.server)));

1680

2919

exitcode = EX_UNAVAILABLE;

1681

2920

goto end;

1682

2921

}

1688

2927

/* Run the main loop */

1689

2928

1690

2929

if(debug){

1691

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

2930

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

1692

2931

}

1693

2932

1694

avahi_simple_poll_loop(mc.simple_poll);

2933

ret = avahi_loop_with_timeout(simple_poll,

2934

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

2935

if(debug){

2936

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

2937

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

2938

}

1695

2939

1696

2940

end:

1697

2941

1698

2942

if(debug){

1699

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

2943

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

1700

2944

}

1701

2945

1702

2946

/* Cleanup things */

2947

free(mc.interfaces);

2948

1703

2949

if(sb != NULL)

1704

2950

avahi_s_service_browser_free(sb);

1705

2951

1706

2952

if(mc.server != NULL)

1707

2953

avahi_server_free(mc.server);

1708

2954

1709

if(mc.simple_poll != NULL)

1710

avahi_simple_poll_free(mc.simple_poll);

2955

if(simple_poll != NULL)

2956

avahi_simple_poll_free(simple_poll);

1711

2957

1712

2958

if(gnutls_initialized){

1713

2959

gnutls_certificate_free_credentials(mc.cred);

1714

gnutls_global_deinit();

1715

2960

gnutls_dh_params_deinit(mc.dh_params);

1716

2961

}

1717

2962

1719

2964

gpgme_release(mc.ctx);

1720

2965

}

1721

2966

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

1729

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1739

}

1740

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

1750

}

1751

}

1752

}

1753

1754

/* Removes the temp directory used by GPGME */

1755

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

and (direntry->d_name[1] == '\0'

1772

or (direntry->d_name[1] == '.'

1773

and direntry->d_name[2] == '\0'))){

1774

continue;

1775

}

1776

char *fullname = NULL;

1777

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

1778

direntry->d_name);

1779

if(ret < 0){

1780

perror("asprintf");

1781

continue;

1782

}

1783

ret = remove(fullname);

1784

if(ret == -1){

1785

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

1786

strerror(errno));

1787

}

1788

free(fullname);

1789

}

1790

closedir(d);

1791

}

1792

ret = rmdir(tempdir);

1793

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

1794

perror("rmdir");

2967

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

2968

has seen */

2969

if(mc.current_server != NULL){

2970

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

2971

while(mc.current_server != NULL){

2972

server *next = mc.current_server->next;

2973

#ifdef __GNUC__

2974

#pragma GCC diagnostic push

2975

#pragma GCC diagnostic ignored "-Wcast-qual"

2976

#endif

2977

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

2978

#ifdef __GNUC__

2979

#pragma GCC diagnostic pop

2980

#endif

2981

free(mc.current_server);

2982

mc.current_server = next;

2983

}

2984

}

2985

2986

/* Re-raise privileges */

2987

{

2988

ret_errno = raise_privileges();

2989

if(ret_errno != 0){

2990

errno = ret_errno;

2991

perror_plus("Failed to raise privileges");

2992

} else {

2993

2994

/* Run network hooks */

2995

run_network_hooks("stop", interfaces_hooks != NULL ?

2996

interfaces_hooks : "", delay);

2997

2998

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

2999

{

3000

char *interface = NULL;

3001

while((interface=argz_next(interfaces_to_take_down,

3002

interfaces_to_take_down_size,

3003

interface))){

3004

ret_errno = take_down_interface(interface);

3005

if(ret_errno != 0){

3006

errno = ret_errno;

3007

perror_plus("Failed to take down interface");

3008

}

3009

}

3010

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

3011

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

3012

" down\n");

3013

}

3014

}

3015

}

3016

3017

ret_errno = lower_privileges_permanently();

3018

if(ret_errno != 0){

3019

errno = ret_errno;

3020

perror_plus("Failed to lower privileges permanently");

3021

}

3022

}

3023

3024

free(interfaces_to_take_down);

3025

free(interfaces_hooks);

3026

3027

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

3028

if(tempdir != NULL){

3029

struct dirent **direntries = NULL;

3030

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

3031

| O_NOFOLLOW

3032

| O_DIRECTORY

3033

| O_PATH));

3034

if(tempdir_fd == -1){

3035

perror_plus("open");

3036

} else {

3037

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

3038

notdotentries, alphasort);

3039

if(numentries >= 0){

3040

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

3041

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

3042

if(ret == -1){

3043

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

3044

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

3045

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

3046

}

3047

free(direntries[i]);

3048

}

3049

3050

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

3051

free(direntries);

3052

if(numentries == -1){

3053

perror_plus("scandir");

3054

}

3055

ret = rmdir(tempdir);

3056

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

3057

perror_plus("rmdir");

3058

}

3059

}

3060

close(tempdir_fd);

1795

3061

}

1796

3062

}

1797

3063

1802

3068

&old_sigterm_action,

1803

3069

NULL));

1804

3070

if(ret == -1){

1805

perror("sigaction");

3071

perror_plus("sigaction");

1806

3072

}

1807

3073

do {

1808

3074

ret = raise(signal_received);

1809

3075

} while(ret != 0 and errno == EINTR);

1810

3076

if(ret != 0){

1811

perror("raise");

3077

perror_plus("raise");

1812

3078

abort();

1813

3079

}

1814

3080

TEMP_FAILURE_RETRY(pause());