/mandos/release : revision 237.15.4

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

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*

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* Everything else is

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*

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

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

32

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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#include <assert.h> /* assert() */

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#include <errno.h> /* perror(), errno,

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program_invocation_short_name */

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#include <time.h> /* nanosleep(), time(), sleep() */

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*/

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

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

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setgid(), pause(), _exit(),

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unlinkat() */

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

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setgid(), pause() */

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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init_gnutls_session(),

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GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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139

AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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163

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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168

void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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174

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

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va_list ap;

191

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va_start (ap, format);

192

177

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

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program_invocation_short_name));

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

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

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

196

180

}

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181

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/*

200

184

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

201

185

* "buffer_length" is how much is already used.

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186

*/

203

__attribute__((nonnull, warn_unused_result))

204

187

size_t incbuffer(char **buffer, size_t buffer_length,

205

size_t buffer_capacity){

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size_t buffer_capacity){

206

189

if(buffer_length + BUFFER_SIZE > buffer_capacity){

207

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

208

if(new_buf == NULL){

209

int old_errno = errno;

210

free(*buffer);

211

errno = old_errno;

212

*buffer = NULL;

190

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

191

if(buffer == NULL){

213

192

return 0;

214

193

}

215

*buffer = new_buf;

216

194

buffer_capacity += BUFFER_SIZE;

217

195

}

218

196

return buffer_capacity;

219

197

}

220

198

221

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

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__attribute__((nonnull, warn_unused_result))

223

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

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int af, server **current_server){

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int add_server(const char *ip, uint16_t port,

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AvahiIfIndex if_index,

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int af){

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int ret;

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

227

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if(new_server == NULL){

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206

perror_plus("malloc");

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return false;

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return -1;

230

208

}

231

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

235

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if(new_server->ip == NULL){

236

214

perror_plus("strdup");

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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");

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#ifdef __GNUC__

244

#pragma GCC diagnostic push

245

#pragma GCC diagnostic ignored "-Wcast-qual"

246

#endif

247

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

248

#ifdef __GNUC__

249

#pragma GCC diagnostic pop

250

#endif

251

free(new_server);

252

return false;

215

return -1;

253

216

}

254

217

/* Special case of first server */

255

if(*current_server == NULL){

218

if (mc.current_server == NULL){

256

219

new_server->next = new_server;

257

220

new_server->prev = new_server;

258

*current_server = new_server;

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mc.current_server = new_server;

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

259

223

} else {

260

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

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new_server->next = *current_server;

262

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

224

new_server->next = mc.current_server;

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

263

226

new_server->prev->next = new_server;

264

(*current_server)->prev = new_server;

265

}

266

return true;

227

mc.current_server->prev = new_server;

228

}

229

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

230

if(ret == -1){

231

perror_plus("clock_gettime");

232

return -1;

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}

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return 0;

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}

268

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/*

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* Initialize GPGME.

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239

*/

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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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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

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

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*/

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bool import_key(const char * const filename){

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bool import_key(const char *filename){

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int ret;

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int fd;

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gpgme_data_t pgp_data;

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

295

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if(rc != GPG_ERR_NO_ERROR){

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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

267

rc = gpgme_op_import(mc.ctx, pgp_data);

302

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if(rc != GPG_ERR_NO_ERROR){

303

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

306

272

}

307

273

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280

}

315

281

316

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if(debug){

317

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

283

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

318

284

}

319

285

320

286

/* Init GPGME */

321

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gpgme_check_version(NULL);

322

288

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

323

289

if(rc != GPG_ERR_NO_ERROR){

324

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

325

gpgme_strsource(rc), gpgme_strerror(rc));

290

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

291

gpgme_strsource(rc), gpgme_strerror(rc));

326

292

return false;

327

293

}

328

294

329

295

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

330

296

rc = gpgme_get_engine_info(&engine_info);

331

297

if(rc != GPG_ERR_NO_ERROR){

332

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

333

gpgme_strsource(rc), gpgme_strerror(rc));

298

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

299

gpgme_strsource(rc), gpgme_strerror(rc));

334

300

return false;

335

301

}

336

302

while(engine_info != NULL){

342

308

engine_info = engine_info->next;

343

309

}

344

310

if(engine_info == NULL){

345

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

346

tempdir);

311

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

347

312

return false;

348

313

}

349

314

350

315

/* Create new GPGME "context" */

351

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

316

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

352

317

if(rc != GPG_ERR_NO_ERROR){

353

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

354

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

355

gpgme_strerror(rc));

318

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

319

gpgme_strsource(rc), gpgme_strerror(rc));

356

320

return false;

357

321

}

358

322

367

331

* Decrypt OpenPGP data.

368

332

* Returns -1 on error

369

333

*/

370

__attribute__((nonnull, warn_unused_result))

371

334

static ssize_t pgp_packet_decrypt(const char *cryptotext,

372

335

size_t crypto_size,

373

char **plaintext,

374

mandos_context *mc){

336

char **plaintext){

375

337

gpgme_data_t dh_crypto, dh_plain;

376

338

gpgme_error_t rc;

377

339

ssize_t ret;

379

341

ssize_t plaintext_length = 0;

380

342

381

343

if(debug){

382

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

344

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

383

345

}

384

346

385

347

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

386

348

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

387

349

0);

388

350

if(rc != GPG_ERR_NO_ERROR){

389

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

390

gpgme_strsource(rc), gpgme_strerror(rc));

351

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

352

gpgme_strsource(rc), gpgme_strerror(rc));

391

353

return -1;

392

354

}

393

355

394

356

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

395

357

rc = gpgme_data_new(&dh_plain);

396

358

if(rc != GPG_ERR_NO_ERROR){

397

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

398

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

399

gpgme_strsource(rc), gpgme_strerror(rc));

359

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

360

gpgme_strsource(rc), gpgme_strerror(rc));

400

361

gpgme_data_release(dh_crypto);

401

362

return -1;

402

363

}

403

364

404

365

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

405

366

data buffer */

406

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

367

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

407

368

if(rc != GPG_ERR_NO_ERROR){

408

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

409

gpgme_strsource(rc), gpgme_strerror(rc));

369

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

370

gpgme_strsource(rc), gpgme_strerror(rc));

410

371

plaintext_length = -1;

411

372

if(debug){

412

373

gpgme_decrypt_result_t result;

413

result = gpgme_op_decrypt_result(mc->ctx);

374

result = gpgme_op_decrypt_result(mc.ctx);

414

375

if(result == NULL){

415

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

376

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

416

377

} else {

417

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

418

result->unsupported_algorithm);

419

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

420

result->wrong_key_usage);

378

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

379

result->unsupported_algorithm);

380

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

381

result->wrong_key_usage);

421

382

if(result->file_name != NULL){

422

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

383

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

423

384

}

424

385

gpgme_recipient_t recipient;

425

386

recipient = result->recipients;

426

387

while(recipient != NULL){

427

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

428

gpgme_pubkey_algo_name

429

(recipient->pubkey_algo));

430

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

431

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

432

recipient->status == GPG_ERR_NO_SECKEY

433

? "No" : "Yes");

388

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

389

gpgme_pubkey_algo_name(recipient->pubkey_algo));

390

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

391

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

392

recipient->status == GPG_ERR_NO_SECKEY

393

? "No" : "Yes");

434

394

recipient = recipient->next;

435

395

}

436

396

}

439

399

}

440

400

441

401

if(debug){

442

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

402

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

443

403

}

444

404

445

405

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

452

412

*plaintext = NULL;

453

413

while(true){

454

414

plaintext_capacity = incbuffer(plaintext,

455

(size_t)plaintext_length,

456

plaintext_capacity);

415

(size_t)plaintext_length,

416

plaintext_capacity);

457

417

if(plaintext_capacity == 0){

458

perror_plus("incbuffer");

459

plaintext_length = -1;

460

goto decrypt_end;

418

perror_plus("incbuffer");

419

plaintext_length = -1;

420

goto decrypt_end;

461

421

}

462

422

463

423

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

476

436

}

477

437

478

438

if(debug){

479

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

439

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

480

440

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

481

441

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

482

442

}

493

453

return plaintext_length;

494

454

}

495

455

496

__attribute__((warn_unused_result))

497

static const char *safer_gnutls_strerror(int value){

498

const char *ret = gnutls_strerror(value);

456

static const char * safer_gnutls_strerror(int value){

457

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

458

-Wunreachable-code */

499

459

if(ret == NULL)

500

460

ret = "(unknown)";

501

461

return ret;

502

462

}

503

463

504

464

/* GnuTLS log function callback */

505

__attribute__((nonnull))

506

465

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

507

466

const char* string){

508

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

467

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

509

468

}

510

469

511

__attribute__((nonnull, warn_unused_result))

512

470

static int init_gnutls_global(const char *pubkeyfilename,

513

const char *seckeyfilename,

514

mandos_context *mc){

471

const char *seckeyfilename){

515

472

int ret;

516

473

517

474

if(debug){

518

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

475

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

519

476

}

520

477

521

478

ret = gnutls_global_init();

522

479

if(ret != GNUTLS_E_SUCCESS){

523

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

524

safer_gnutls_strerror(ret));

480

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

481

safer_gnutls_strerror(ret));

525

482

return -1;

526

483

}

527

484

534

491

}

535

492

536

493

/* OpenPGP credentials */

537

ret = gnutls_certificate_allocate_credentials(&mc->cred);

494

ret = gnutls_certificate_allocate_credentials(&mc.cred);

538

495

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

496

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

497

safer_gnutls_strerror(ret));

541

498

gnutls_global_deinit();

542

499

return -1;

543

500

}

544

501

545

502

if(debug){

546

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

547

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

548

pubkeyfilename,

549

seckeyfilename);

503

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

504

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

505

seckeyfilename);

550

506

}

551

507

552

508

ret = gnutls_certificate_set_openpgp_key_file

553

(mc->cred, pubkeyfilename, seckeyfilename,

509

(mc.cred, pubkeyfilename, seckeyfilename,

554

510

GNUTLS_OPENPGP_FMT_BASE64);

555

511

if(ret != GNUTLS_E_SUCCESS){

556

fprintf_plus(stderr,

557

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

558

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

559

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

560

safer_gnutls_strerror(ret));

512

fprintf(stderr,

513

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

514

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

515

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

516

safer_gnutls_strerror(ret));

561

517

goto globalfail;

562

518

}

563

519

564

520

/* GnuTLS server initialization */

565

ret = gnutls_dh_params_init(&mc->dh_params);

521

ret = gnutls_dh_params_init(&mc.dh_params);

566

522

if(ret != GNUTLS_E_SUCCESS){

567

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

568

" initialization: %s\n",

569

safer_gnutls_strerror(ret));

523

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

524

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

570

525

goto globalfail;

571

526

}

572

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

527

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

573

528

if(ret != GNUTLS_E_SUCCESS){

574

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

575

safer_gnutls_strerror(ret));

529

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

530

safer_gnutls_strerror(ret));

576

531

goto globalfail;

577

532

}

578

533

579

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

534

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

580

535

581

536

return 0;

582

537

583

538

globalfail:

584

539

585

gnutls_certificate_free_credentials(mc->cred);

540

gnutls_certificate_free_credentials(mc.cred);

586

541

gnutls_global_deinit();

587

gnutls_dh_params_deinit(mc->dh_params);

542

gnutls_dh_params_deinit(mc.dh_params);

588

543

return -1;

589

544

}

590

545

591

__attribute__((nonnull, warn_unused_result))

592

static int init_gnutls_session(gnutls_session_t *session,

593

mandos_context *mc){

546

static int init_gnutls_session(gnutls_session_t *session){

594

547

int ret;

595

548

/* GnuTLS session creation */

596

549

do {

600

553

}

601

554

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

602

555

if(ret != GNUTLS_E_SUCCESS){

603

fprintf_plus(stderr,

604

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

605

safer_gnutls_strerror(ret));

556

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

557

safer_gnutls_strerror(ret));

606

558

}

607

559

608

560

{

609

561

const char *err;

610

562

do {

611

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

563

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

612

564

if(quit_now){

613

565

gnutls_deinit(*session);

614

566

return -1;

615

567

}

616

568

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

617

569

if(ret != GNUTLS_E_SUCCESS){

618

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

619

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

620

safer_gnutls_strerror(ret));

570

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

571

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

572

safer_gnutls_strerror(ret));

621

573

gnutls_deinit(*session);

622

574

return -1;

623

575

}

625

577

626

578

do {

627

579

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

628

mc->cred);

580

mc.cred);

629

581

if(quit_now){

630

582

gnutls_deinit(*session);

631

583

return -1;

632

584

}

633

585

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

634

586

if(ret != GNUTLS_E_SUCCESS){

635

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

636

safer_gnutls_strerror(ret));

587

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

588

safer_gnutls_strerror(ret));

637

589

gnutls_deinit(*session);

638

590

return -1;

639

591

}

641

593

/* ignore client certificate if any. */

642

594

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

643

595

644

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

596

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

645

597

646

598

return 0;

647

599

}

651

603

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

652

604

653

605

/* Called when a Mandos server is found */

654

__attribute__((nonnull, warn_unused_result))

655

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

606

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

656

607

AvahiIfIndex if_index,

657

int af, mandos_context *mc){

608

int af){

658

609

int ret, tcp_sd = -1;

659

610

ssize_t sret;

660

struct sockaddr_storage to;

611

union {

612

struct sockaddr_in in;

613

struct sockaddr_in6 in6;

614

} to;

661

615

char *buffer = NULL;

662

616

char *decrypted_buffer = NULL;

663

617

size_t buffer_length = 0;

682

636

pf = PF_INET;

683

637

break;

684

638

default:

685

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

639

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

686

640

errno = EINVAL;

687

641

return -1;

688

642

}

689

643

690

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

691

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

692

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

693

bool match = false;

694

{

695

char *interface = NULL;

696

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

697

interface))){

698

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

699

match = true;

700

break;

701

}

702

}

703

}

704

if(not match){

705

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

706

connect to the server */

707

if(debug){

708

char interface[IF_NAMESIZE];

709

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

710

perror_plus("if_indextoname");

711

} else {

712

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

713

" \"%s\"\n",

714

if_indextoname((unsigned int)if_index,

715

interface));

716

}

717

}

718

return -1;

719

}

720

}

721

722

ret = init_gnutls_session(&session, mc);

644

ret = init_gnutls_session(&session);

723

645

if(ret != 0){

724

646

return -1;

725

647

}

726

648

727

649

if(debug){

728

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

729

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

650

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

651

"\n", ip, port);

730

652

}

731

653

732

654

tcp_sd = socket(pf, SOCK_STREAM, 0);

744

666

745

667

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

746

668

if(af == AF_INET6){

747

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

748

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

669

to.in6.sin6_family = (sa_family_t)af;

670

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

749

671

} else { /* IPv4 */

750

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

751

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

672

to.in.sin_family = (sa_family_t)af;

673

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

752

674

}

753

675

if(ret < 0 ){

754

676

int e = errno;

758

680

}

759

681

if(ret == 0){

760

682

int e = errno;

761

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

683

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

762

684

errno = e;

763

685

goto mandos_end;

764

686

}

765

687

if(af == AF_INET6){

766

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

767

if(IN6_IS_ADDR_LINKLOCAL

768

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

688

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

689

-Wconversion and

690

-Wunreachable-code */

691

692

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

693

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

694

-Wunreachable-code*/

769

695

if(if_index == AVAHI_IF_UNSPEC){

770

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

771

" incomplete without a network interface\n");

696

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

697

" without a network interface\n");

772

698

errno = EINVAL;

773

699

goto mandos_end;

774

700

}

775

701

/* Set the network interface number as scope */

776

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

702

to.in6.sin6_scope_id = (uint32_t)if_index;

777

703

}

778

704

} else {

779

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

705

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

706

-Wconversion and

707

-Wunreachable-code */

780

708

}

781

709

782

710

if(quit_now){

790

718

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

791

719

perror_plus("if_indextoname");

792

720

} else {

793

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

794

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

721

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

722

ip, interface, port);

795

723

}

796

724

} else {

797

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

798

ip, (uintmax_t)port);

725

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

726

port);

799

727

}

800

728

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

801

729

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

730

const char *pcret;

802

731

if(af == AF_INET6){

803

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

804

sizeof(struct sockaddr_in6),

805

addrstr, sizeof(addrstr), NULL, 0,

806

NI_NUMERICHOST);

732

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

733

sizeof(addrstr));

807

734

} else {

808

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

809

sizeof(struct sockaddr_in),

810

addrstr, sizeof(addrstr), NULL, 0,

811

NI_NUMERICHOST);

735

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

736

sizeof(addrstr));

812

737

}

813

if(ret == EAI_SYSTEM){

814

perror_plus("getnameinfo");

815

} else if(ret != 0) {

816

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

817

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

818

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

738

if(pcret == NULL){

739

perror_plus("inet_ntop");

740

} else {

741

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

742

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

743

}

819

744

}

820

745

}

821

746

825

750

}

826

751

827

752

if(af == AF_INET6){

828

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

829

sizeof(struct sockaddr_in6));

753

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

830

754

} else {

831

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

832

sizeof(struct sockaddr_in));

755

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

833

756

}

834

757

if(ret < 0){

835

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

758

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

836

759

int e = errno;

837

760

perror_plus("connect");

838

761

errno = e;

850

773

while(true){

851

774

size_t out_size = strlen(out);

852

775

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

853

out_size - written));

776

out_size - written));

854

777

if(ret == -1){

855

778

int e = errno;

856

779

perror_plus("write");

876

799

}

877

800

878

801

if(debug){

879

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

802

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

880

803

}

881

804

882

805

if(quit_now){

884

807

goto mandos_end;

885

808

}

886

809

887

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

888

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

889

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

890

gnutls_transport_set_ptr(session,

891

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

810

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

811

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

892

812

893

813

if(quit_now){

894

814

errno = EINTR;

905

825

906

826

if(ret != GNUTLS_E_SUCCESS){

907

827

if(debug){

908

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

828

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

909

829

gnutls_perror(ret);

910

830

}

911

831

errno = EPROTO;

915

835

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

916

836

917

837

if(debug){

918

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

919

" %s\n", ip);

838

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

839

ip);

920

840

}

921

841

922

842

while(true){

927

847

}

928

848

929

849

buffer_capacity = incbuffer(&buffer, buffer_length,

930

buffer_capacity);

850

buffer_capacity);

931

851

if(buffer_capacity == 0){

932

852

int e = errno;

933

853

perror_plus("incbuffer");

960

880

}

961

881

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

962

882

if(ret < 0){

963

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

964

"***\n");

883

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

965

884

gnutls_perror(ret);

966

885

errno = EPROTO;

967

886

goto mandos_end;

968

887

}

969

888

break;

970

889

default:

971

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

972

" encrypted session with Mandos server\n");

890

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

891

" encrypted session with Mandos server\n");

973

892

gnutls_bye(session, GNUTLS_SHUT_RDWR);

974

893

errno = EIO;

975

894

goto mandos_end;

980

899

}

981

900

982

901

if(debug){

983

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

902

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

984

903

}

985

904

986

905

if(quit_now){

998

917

999

918

if(buffer_length > 0){

1000

919

ssize_t decrypted_buffer_size;

1001

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1002

&decrypted_buffer, mc);

920

decrypted_buffer_size = pgp_packet_decrypt(buffer,

921

buffer_length,

922

&decrypted_buffer);

1003

923

if(decrypted_buffer_size >= 0){

1004

924

1005

925

written = 0;

1015

935

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

1016

936

int e = errno;

1017

937

if(debug){

1018

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

1019

strerror(errno));

938

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

939

strerror(errno));

1020

940

}

1021

941

errno = e;

1022

942

goto mandos_end;

1053

973

return retval;

1054

974

}

1055

975

1056

__attribute__((nonnull))

1057

976

static void resolve_callback(AvahiSServiceResolver *r,

1058

977

AvahiIfIndex interface,

1059

978

AvahiProtocol proto,

1067

986

AVAHI_GCC_UNUSED AvahiStringList *txt,

1068

987

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1069

988

flags,

1070

void *mc){

1071

if(r == NULL){

1072

return;

1073

}

989

AVAHI_GCC_UNUSED void* userdata){

990

assert(r);

1074

991

1075

992

/* Called whenever a service has been resolved successfully or

1076

993

timed out */

1077

994

1078

995

if(quit_now){

1079

avahi_s_service_resolver_free(r);

1080

996

return;

1081

997

}

1082

998

1083

999

switch(event){

1084

1000

default:

1085

1001

case AVAHI_RESOLVER_FAILURE:

1086

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

1087

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

1088

domain,

1089

avahi_strerror(avahi_server_errno

1090

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

1002

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

1003

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

1004

avahi_strerror(avahi_server_errno(mc.server)));

1091

1005

break;

1092

1006

1093

1007

case AVAHI_RESOLVER_FOUND:

1095

1009

char ip[AVAHI_ADDRESS_STR_MAX];

1096

1010

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

1097

1011

if(debug){

1098

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

1099

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

1100

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

1012

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

1013

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

1014

ip, (intmax_t)interface, port);

1101

1015

}

1102

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

1103

interface,

1104

avahi_proto_to_af(proto),

1105

mc);

1016

int ret = start_mandos_communication(ip, port, interface,

1017

avahi_proto_to_af(proto));

1106

1018

if(ret == 0){

1107

avahi_simple_poll_quit(simple_poll);

1019

avahi_simple_poll_quit(mc.simple_poll);

1108

1020

} else {

1109

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

1110

avahi_proto_to_af(proto),

1111

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

1112

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

1113

" list\n", name);

1114

}

1021

ret = add_server(ip, port, interface,

1022

avahi_proto_to_af(proto));

1115

1023

}

1116

1024

}

1117

1025

}

1127

1035

const char *domain,

1128

1036

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1129

1037

flags,

1130

void *mc){

1131

if(b == NULL){

1132

return;

1133

}

1038

AVAHI_GCC_UNUSED void* userdata){

1039

assert(b);

1134

1040

1135

1041

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

1136

1042

is removed from the LAN */

1143

1049

default:

1144

1050

case AVAHI_BROWSER_FAILURE:

1145

1051

1146

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

1147

avahi_strerror(avahi_server_errno

1148

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

1149

avahi_simple_poll_quit(simple_poll);

1052

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

1053

avahi_strerror(avahi_server_errno(mc.server)));

1054

avahi_simple_poll_quit(mc.simple_poll);

1150

1055

return;

1151

1056

1152

1057

case AVAHI_BROWSER_NEW:

1155

1060

the callback function is called the Avahi server will free the

1156

1061

resolver for us. */

1157

1062

1158

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

1159

interface, protocol, name, type,

1160

domain, protocol, 0,

1161

resolve_callback, mc) == NULL)

1162

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

1163

" %s\n", name,

1164

avahi_strerror(avahi_server_errno

1165

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

1063

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

1064

name, type, domain, protocol, 0,

1065

resolve_callback, NULL) == NULL)

1066

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

1067

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

1166

1068

break;

1167

1069

1168

1070

case AVAHI_BROWSER_REMOVE:

1171

1073

case AVAHI_BROWSER_ALL_FOR_NOW:

1172

1074

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1173

1075

if(debug){

1174

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

1175

" searching...\n");

1076

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

1176

1077

}

1177

1078

break;

1178

1079

}

1187

1088

signal_received = sig;

1188

1089

int old_errno = errno;

1189

1090

/* set main loop to exit */

1190

if(simple_poll != NULL){

1191

avahi_simple_poll_quit(simple_poll);

1091

if(mc.simple_poll != NULL){

1092

avahi_simple_poll_quit(mc.simple_poll);

1192

1093

}

1193

1094

errno = old_errno;

1194

1095

}

1195

1096

1196

__attribute__((nonnull, warn_unused_result))

1197

1097

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

1198

1098

int ret;

1199

error_t ret_errno;

1200

1099

1201

1100

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

1202

1101

if(s < 0){

1203

ret_errno = errno;

1204

1102

perror_plus("socket");

1205

errno = ret_errno;

1206

1103

return false;

1207

1104

}

1208

1105

strcpy(ifr->ifr_name, ifname);

1209

1106

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1210

1107

if(ret == -1){

1211

1108

if(debug){

1212

ret_errno = errno;

1213

1109

perror_plus("ioctl SIOCGIFFLAGS");

1214

errno = ret_errno;

1215

1110

}

1216

1111

return false;

1217

1112

}

1218

1113

return true;

1219

1114

}

1220

1115

1221

__attribute__((nonnull, warn_unused_result))

1222

1116

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

1223

1117

1224

1118

/* Reject the loopback device */

1225

1119

if(ifr->ifr_flags & IFF_LOOPBACK){

1226

1120

if(debug){

1227

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

1228

ifname);

1121

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

1122

ifname);

1229

1123

}

1230

1124

return false;

1231

1125

}

1232

1126

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

1233

1127

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

1234

1128

if(debug){

1235

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

1236

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

1129

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

1130

ifname);

1237

1131

}

1238

1132

return true;

1239

1133

}

1240

1134

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

1241

1135

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

1242

1136

if(debug){

1243

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1244

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

1137

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

1138

ifname);

1245

1139

}

1246

1140

return false;

1247

1141

}

1248

1142

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

1249

1143

if(ifr->ifr_flags & IFF_NOARP){

1250

1144

if(debug){

1251

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

1252

ifname);

1145

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

1253

1146

}

1254

1147

return false;

1255

1148

}

1256

1149

1257

1150

/* Accept this device */

1258

1151

if(debug){

1259

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

1152

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

1260

1153

}

1261

1154

return true;

1262

1155

}

1266

1159

* corresponds to an acceptable network device.

1267

1160

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

1268

1161

*/

1269

__attribute__((nonnull, warn_unused_result))

1270

1162

int good_interface(const struct dirent *if_entry){

1163

int ret;

1271

1164

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

1272

1165

return 0;

1273

1166

}

1274

1275

1167

struct ifreq ifr;

1168

1276

1169

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

1277

if(debug){

1278

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

1279

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

1280

}

1281

1170

return 0;

1282

1171

}

1283

1172

1288

1177

}

1289

1178

1290

1179

/*

1291

* This function determines if a network interface is up.

1292

*/

1293

__attribute__((nonnull, warn_unused_result))

1294

bool interface_is_up(const char *interface){

1295

struct ifreq ifr;

1296

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

1297

if(debug){

1298

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

1299

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

1300

}

1301

return false;

1302

}

1303

1304

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

1305

}

1306

1307

/*

1308

* This function determines if a network interface is running

1309

*/

1310

__attribute__((nonnull, warn_unused_result))

1311

bool interface_is_running(const char *interface){

1312

struct ifreq ifr;

1313

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

1314

if(debug){

1315

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

1316

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

1317

}

1318

return false;

1319

}

1320

1321

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

1322

}

1323

1324

__attribute__((nonnull, pure, warn_unused_result))

1180

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

1181

* corresponds to an acceptable network device which is up.

1182

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

1183

*/

1184

int up_interface(const struct dirent *if_entry){

1185

ssize_t ssret;

1186

char *flagname = NULL;

1187

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

1188

return 0;

1189

}

1190

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

1191

if_entry->d_name);

1192

if(ret < 0){

1193

perror_plus("asprintf");

1194

return 0;

1195

}

1196

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

1197

if(flags_fd == -1){

1198

perror_plus("open");

1199

free(flagname);

1200

return 0;

1201

}

1202

free(flagname);

1203

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

1204

/* read line from flags_fd */

1205

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

1206

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

1207

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

1208

if(flagstring == NULL){

1209

perror_plus("malloc");

1210

close(flags_fd);

1211

return 0;

1212

}

1213

while(to_read > 0){

1214

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

1215

(size_t)to_read));

1216

if(ssret == -1){

1217

perror_plus("read");

1218

free(flagstring);

1219

close(flags_fd);

1220

return 0;

1221

}

1222

to_read -= ssret;

1223

if(ssret == 0){

1224

break;

1225

}

1226

}

1227

close(flags_fd);

1228

intmax_t tmpmax;

1229

char *tmp;

1230

errno = 0;

1231

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

1232

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

1233

and not (isspace(*tmp)))

1234

or tmpmax != (ifreq_flags)tmpmax){

1235

if(debug){

1236

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

1237

flagstring, if_entry->d_name);

1238

}

1239

free(flagstring);

1240

return 0;

1241

}

1242

free(flagstring);

1243

ifreq_flags flags = (ifreq_flags)tmpmax;

1244

/* Reject the loopback device */

1245

if(flags & IFF_LOOPBACK){

1246

if(debug){

1247

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

1248

if_entry->d_name);

1249

}

1250

return 0;

1251

}

1252

1253

/* Reject down interfaces */

1254

if(not (flags & IFF_UP)){

1255

return 0;

1256

}

1257

1258

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

1259

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

1260

if(debug){

1261

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

1262

if_entry->d_name);

1263

}

1264

return 1;

1265

}

1266

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

1267

if(not (flags & IFF_BROADCAST)){

1268

if(debug){

1269

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

1270

if_entry->d_name);

1271

}

1272

return 0;

1273

}

1274

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

1275

if(flags & IFF_NOARP){

1276

if(debug){

1277

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

1278

if_entry->d_name);

1279

}

1280

return 0;

1281

}

1282

/* Accept this device */

1283

if(debug){

1284

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

1285

if_entry->d_name);

1286

}

1287

return 1;

1288

}

1289

1325

1290

int notdotentries(const struct dirent *direntry){

1326

1291

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

1327

1292

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

1334

1299

}

1335

1300

1336

1301

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

1337

__attribute__((nonnull, warn_unused_result))

1338

1302

int runnable_hook(const struct dirent *direntry){

1339

1303

int ret;

1340

size_t sret;

1341

1304

struct stat st;

1342

1305

1343

1306

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

1345

1308

return 0;

1346

1309

}

1347

1310

1348

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

1349

"abcdefghijklmnopqrstuvwxyz"

1350

"0123456789"

1351

"_.-");

1352

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

1353

/* Contains non-allowed characters */

1354

if(debug){

1355

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

1356

direntry->d_name);

1357

}

1358

return 0;

1359

}

1360

1361

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

1311

/* Save pointer to last character */

1312

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

1313

1314

if(*end == '~'){

1315

/* Backup name~ */

1316

return 0;

1317

}

1318

1319

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

1320

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

1321

/* Temporary #name# */

1322

return 0;

1323

}

1324

1325

/* XXX more rules here */

1326

1327

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

1362

1328

if(ret == -1){

1363

1329

if(debug){

1364

perror_plus("Could not stat hook");

1330

perror_plus("Could not stat plugin");

1365

1331

}

1366

1332

return 0;

1367

1333

}

1368

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

1334

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

1369

1335

/* Not a regular file */

1370

if(debug){

1371

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

1372

direntry->d_name);

1373

}

1374

1336

return 0;

1375

1337

}

1376

1338

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

1377

1339

/* Not executable */

1378

if(debug){

1379

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

1380

direntry->d_name);

1381

}

1382

1340

return 0;

1383

1341

}

1384

if(debug){

1385

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

1386

direntry->d_name);

1387

}

1388

1342

return 1;

1389

1343

}

1390

1344

1391

__attribute__((nonnull, warn_unused_result))

1392

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1393

mandos_context *mc){

1345

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1394

1346

int ret;

1395

1347

struct timespec now;

1396

1348

struct timespec waited_time;

1397

1349

intmax_t block_time;

1398

1350

1399

1351

while(true){

1400

if(mc->current_server == NULL){

1401

if(debug){

1402

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

1403

" No timeout!\n");

1352

if(mc.current_server == NULL){

1353

if (debug){

1354

fprintf(stderr,

1355

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

1404

1356

}

1405

1357

ret = avahi_simple_poll_iterate(s, -1);

1406

1358

} else {

1407

if(debug){

1408

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

1409

" it, or wait\n");

1359

if (debug){

1360

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

1361

" or wait\n");

1410

1362

}

1411

1363

/* the current time */

1412

1364

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1417

1369

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

1418

1370

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

1419

1371

waited_time.tv_sec = (now.tv_sec

1420

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

1372

- mc.current_server->last_seen.tv_sec);

1421

1373

waited_time.tv_nsec = (now.tv_nsec

1422

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

1374

- mc.current_server->last_seen.tv_nsec);

1423

1375

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

1424

1376

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

1425

1377

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

1427

1379

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

1428

1380

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

1429

1381

1430

if(debug){

1431

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

1432

block_time);

1382

if (debug){

1383

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

1433

1384

}

1434

1385

1435

1386

if(block_time <= 0){

1436

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

1437

mc->current_server->port,

1438

mc->current_server->if_index,

1439

mc->current_server->af, mc);

1387

ret = start_mandos_communication(mc.current_server->ip,

1388

mc.current_server->port,

1389

mc.current_server->if_index,

1390

mc.current_server->af);

1440

1391

if(ret == 0){

1441

avahi_simple_poll_quit(s);

1392

avahi_simple_poll_quit(mc.simple_poll);

1442

1393

return 0;

1443

1394

}

1444

1395

ret = clock_gettime(CLOCK_MONOTONIC,

1445

&mc->current_server->last_seen);

1396

&mc.current_server->last_seen);

1446

1397

if(ret == -1){

1447

1398

perror_plus("clock_gettime");

1448

1399

return -1;

1449

1400

}

1450

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

1401

mc.current_server = mc.current_server->next;

1451

1402

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

1452

1403

servers, but don't block */

1453

1404

}

1455

1406

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

1456

1407

}

1457

1408

if(ret != 0){

1458

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

1409

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

1459

1410

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

1460

1411

}

1461

1412

}

1462

1413

}

1463

1414

}

1464

1415

1465

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

1466

__attribute__((warn_unused_result))

1467

error_t raise_privileges(void){

1468

error_t old_errno = errno;

1469

error_t ret_errno = 0;

1470

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

1471

ret_errno = errno;

1472

}

1473

errno = old_errno;

1474

return ret_errno;

1475

}

1476

1477

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

1478

__attribute__((warn_unused_result))

1479

error_t raise_privileges_permanently(void){

1480

error_t old_errno = errno;

1481

error_t ret_errno = raise_privileges();

1482

if(ret_errno != 0){

1483

errno = old_errno;

1484

return ret_errno;

1485

}

1486

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

1487

ret_errno = errno;

1488

}

1489

errno = old_errno;

1490

return ret_errno;

1491

}

1492

1493

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

1494

__attribute__((warn_unused_result))

1495

error_t lower_privileges(void){

1496

error_t old_errno = errno;

1497

error_t ret_errno = 0;

1498

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

1499

ret_errno = errno;

1500

}

1501

errno = old_errno;

1502

return ret_errno;

1503

}

1504

1505

/* Lower privileges permanently */

1506

__attribute__((warn_unused_result))

1507

error_t lower_privileges_permanently(void){

1508

error_t old_errno = errno;

1509

error_t ret_errno = 0;

1510

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

1511

ret_errno = errno;

1512

}

1513

errno = old_errno;

1514

return ret_errno;

1515

}

1516

1517

__attribute__((nonnull))

1518

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

1519

const float delay){

1520

struct dirent **direntries = NULL;

1521

if(hookdir_fd == -1){

1522

hookdir_fd = open(hookdir, O_RDONLY);

1523

if(hookdir_fd == -1){

1524

if(errno == ENOENT){

1525

if(debug){

1526

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

1527

" found\n", hookdir);

1528

}

1529

} else {

1530

perror_plus("open");

1531

}

1532

return;

1533

}

1534

}

1535

#ifdef __GLIBC__

1536

#if __GLIBC_PREREQ(2, 15)

1537

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

1538

runnable_hook, alphasort);

1539

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

1540

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

1541

alphasort);

1542

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

1543

#else /* not __GLIBC__ */

1544

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

1545

alphasort);

1546

#endif /* not __GLIBC__ */

1547

if(numhooks == -1){

1548

perror_plus("scandir");

1549

return;

1550

}

1551

struct dirent *direntry;

1552

int ret;

1553

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

1554

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

1555

direntry = direntries[i];

1556

if(debug){

1557

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

1558

direntry->d_name);

1559

}

1560

pid_t hook_pid = fork();

1561

if(hook_pid == 0){

1562

/* Child */

1563

/* Raise privileges */

1564

errno = raise_privileges_permanently();

1565

if(errno != 0){

1566

perror_plus("Failed to raise privileges");

1567

_exit(EX_NOPERM);

1568

}

1569

/* Set group */

1570

errno = 0;

1571

ret = setgid(0);

1572

if(ret == -1){

1573

perror_plus("setgid");

1574

_exit(EX_NOPERM);

1575

}

1576

/* Reset supplementary groups */

1577

errno = 0;

1578

ret = setgroups(0, NULL);

1579

if(ret == -1){

1580

perror_plus("setgroups");

1581

_exit(EX_NOPERM);

1582

}

1583

ret = dup2(devnull, STDIN_FILENO);

1584

if(ret == -1){

1585

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

1586

_exit(EX_OSERR);

1587

}

1588

ret = close(devnull);

1589

if(ret == -1){

1590

perror_plus("close");

1591

_exit(EX_OSERR);

1592

}

1593

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1594

if(ret == -1){

1595

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

1596

_exit(EX_OSERR);

1597

}

1598

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

1599

if(ret == -1){

1600

perror_plus("setenv");

1601

_exit(EX_OSERR);

1602

}

1603

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

1604

if(ret == -1){

1605

perror_plus("setenv");

1606

_exit(EX_OSERR);

1607

}

1608

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

1609

if(ret == -1){

1610

perror_plus("setenv");

1611

_exit(EX_OSERR);

1612

}

1613

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

1614

if(ret == -1){

1615

perror_plus("setenv");

1616

_exit(EX_OSERR);

1617

}

1618

char *delaystring;

1619

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

1620

if(ret == -1){

1621

perror_plus("asprintf");

1622

_exit(EX_OSERR);

1623

}

1624

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

1625

if(ret == -1){

1626

free(delaystring);

1627

perror_plus("setenv");

1628

_exit(EX_OSERR);

1629

}

1630

free(delaystring);

1631

if(connect_to != NULL){

1632

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

1633

if(ret == -1){

1634

perror_plus("setenv");

1635

_exit(EX_OSERR);

1636

}

1637

}

1638

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

1639

if(hook_fd == -1){

1640

perror_plus("openat");

1641

_exit(EXIT_FAILURE);

1642

}

1643

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

1644

perror_plus("close");

1645

_exit(EXIT_FAILURE);

1646

}

1647

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

1648

environ) == -1){

1649

perror_plus("fexecve");

1650

_exit(EXIT_FAILURE);

1651

}

1652

} else {

1653

if(hook_pid == -1){

1654

perror_plus("fork");

1655

free(direntry);

1656

continue;

1657

}

1658

int status;

1659

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

1660

perror_plus("waitpid");

1661

free(direntry);

1662

continue;

1663

}

1664

if(WIFEXITED(status)){

1665

if(WEXITSTATUS(status) != 0){

1666

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

1667

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

1668

WEXITSTATUS(status));

1669

free(direntry);

1670

continue;

1671

}

1672

} else if(WIFSIGNALED(status)){

1673

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

1674

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

1675

WTERMSIG(status));

1676

free(direntry);

1677

continue;

1678

} else {

1679

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

1680

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

1681

free(direntry);

1682

continue;

1683

}

1684

}

1685

if(debug){

1686

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

1687

direntry->d_name);

1688

}

1689

free(direntry);

1690

}

1691

free(direntries);

1692

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

1693

perror_plus("close");

1694

} else {

1695

hookdir_fd = -1;

1696

}

1697

close(devnull);

1698

}

1699

1700

__attribute__((nonnull, warn_unused_result))

1701

error_t bring_up_interface(const char *const interface,

1702

const float delay){

1703

error_t old_errno = errno;

1704

int ret;

1705

struct ifreq network;

1706

unsigned int if_index = if_nametoindex(interface);

1707

if(if_index == 0){

1708

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

1709

errno = old_errno;

1710

return ENXIO;

1711

}

1712

1713

if(quit_now){

1714

errno = old_errno;

1715

return EINTR;

1716

}

1717

1718

if(not interface_is_up(interface)){

1719

error_t ret_errno = 0, ioctl_errno = 0;

1720

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

1721

ret_errno = errno;

1722

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

1723

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

1724

errno = old_errno;

1725

return ret_errno;

1726

}

1727

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

1728

1729

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

1730

if(sd == -1){

1731

ret_errno = errno;

1732

perror_plus("socket");

1733

errno = old_errno;

1734

return ret_errno;

1735

}

1736

1737

if(quit_now){

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

errno = old_errno;

1743

return EINTR;

1744

}

1745

1746

if(debug){

1747

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

1748

interface);

1749

}

1750

1751

/* Raise privileges */

1752

ret_errno = raise_privileges();

1753

if(ret_errno != 0){

1754

errno = ret_errno;

1755

perror_plus("Failed to raise privileges");

1756

}

1757

1758

#ifdef __linux__

1759

int ret_linux;

1760

bool restore_loglevel = false;

1761

if(ret_errno == 0){

1762

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1763

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

1764

ret_linux = klogctl(8, NULL, 5);

1765

if(ret_linux == -1){

1766

perror_plus("klogctl");

1767

} else {

1768

restore_loglevel = true;

1769

}

1770

}

1771

#endif /* __linux__ */

1772

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

1773

ioctl_errno = errno;

1774

#ifdef __linux__

1775

if(restore_loglevel){

1776

ret_linux = klogctl(7, NULL, 0);

1777

if(ret_linux == -1){

1778

perror_plus("klogctl");

1779

}

1780

}

1781

#endif /* __linux__ */

1782

1783

/* If raise_privileges() succeeded above */

1784

if(ret_errno == 0){

1785

/* Lower privileges */

1786

ret_errno = lower_privileges();

1787

if(ret_errno != 0){

1788

errno = ret_errno;

1789

perror_plus("Failed to lower privileges");

1790

}

1791

}

1792

1793

/* Close the socket */

1794

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

1795

if(ret == -1){

1796

perror_plus("close");

1797

}

1798

1799

if(ret_setflags == -1){

1800

errno = ioctl_errno;

1801

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1802

errno = old_errno;

1803

return ioctl_errno;

1804

}

1805

} else if(debug){

1806

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

1807

interface);

1808

}

1809

1810

/* Sleep checking until interface is running.

1811

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

1812

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

1813

if(interface_is_running(interface)){

1814

break;

1815

}

1816

struct timespec sleeptime = { .tv_nsec = 250000000 };

1817

ret = nanosleep(&sleeptime, NULL);

1818

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

1819

perror_plus("nanosleep");

1820

}

1821

}

1822

1823

errno = old_errno;

1824

return 0;

1825

}

1826

1827

__attribute__((nonnull, warn_unused_result))

1828

error_t take_down_interface(const char *const interface){

1829

error_t old_errno = errno;

1830

struct ifreq network;

1831

unsigned int if_index = if_nametoindex(interface);

1832

if(if_index == 0){

1833

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

1834

errno = old_errno;

1835

return ENXIO;

1836

}

1837

if(interface_is_up(interface)){

1838

error_t ret_errno = 0, ioctl_errno = 0;

1839

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

1840

ret_errno = errno;

1841

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

1842

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

1843

errno = old_errno;

1844

return ret_errno;

1845

}

1846

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

1847

1848

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

1849

if(sd == -1){

1850

ret_errno = errno;

1851

perror_plus("socket");

1852

errno = old_errno;

1853

return ret_errno;

1854

}

1855

1856

if(debug){

1857

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

1858

interface);

1859

}

1860

1861

/* Raise privileges */

1862

ret_errno = raise_privileges();

1863

if(ret_errno != 0){

1864

errno = ret_errno;

1865

perror_plus("Failed to raise privileges");

1866

}

1867

1868

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

1869

ioctl_errno = errno;

1870

1871

/* If raise_privileges() succeeded above */

1872

if(ret_errno == 0){

1873

/* Lower privileges */

1874

ret_errno = lower_privileges();

1875

if(ret_errno != 0){

1876

errno = ret_errno;

1877

perror_plus("Failed to lower privileges");

1878

}

1879

}

1880

1881

/* Close the socket */

1882

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

1883

if(ret == -1){

1884

perror_plus("close");

1885

}

1886

1887

if(ret_setflags == -1){

1888

errno = ioctl_errno;

1889

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1890

errno = old_errno;

1891

return ioctl_errno;

1892

}

1893

} else if(debug){

1894

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

1895

interface);

1896

}

1897

1898

errno = old_errno;

1899

return 0;

1900

}

1901

1902

1416

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

1903

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

1904

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

1905

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

1906

.interfaces = NULL, .interfaces_size = 0 };

1907

1417

AvahiSServiceBrowser *sb = NULL;

1908

error_t ret_errno;

1418

int error;

1909

1419

int ret;

1910

1420

intmax_t tmpmax;

1911

1421

char *tmp;

1912

1422

int exitcode = EXIT_SUCCESS;

1913

char *interfaces_to_take_down = NULL;

1914

size_t interfaces_to_take_down_size = 0;

1915

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

1916

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

1917

char *tempdir = NULL;

1423

const char *interface = "";

1424

struct ifreq network;

1425

int sd = -1;

1426

bool take_down_interface = false;

1427

uid_t uid;

1428

gid_t gid;

1429

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

1430

bool tempdir_created = false;

1918

1431

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1919

1432

const char *seckey = PATHDIR "/" SECKEY;

1920

1433

const char *pubkey = PATHDIR "/" PUBKEY;

1921

char *interfaces_hooks = NULL;

1922

1434

1923

1435

bool gnutls_initialized = false;

1924

1436

bool gpgme_initialized = false;

1986

1498

.group = 2 },

1987

1499

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

1988

1500

.arg = "SECONDS",

1989

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

1990

.group = 2 },

1991

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

1992

.arg = "DIR",

1993

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

1501

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

1994

1502

.group = 2 },

1995

1503

/*

1996

1504

* These reproduce what we would get without ARGP_NO_HELP

2015

1523

connect_to = arg;

2016

1524

break;

2017

1525

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

2018

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

2019

arg, (int)',');

2020

if(ret_errno != 0){

2021

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

2022

}

1526

interface = arg;

2023

1527

break;

2024

1528

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

2025

1529

seckey = arg;

2054

1558

argp_error(state, "Bad retry interval");

2055

1559

}

2056

1560

break;

2057

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

2058

hookdir = arg;

2059

break;

2060

1561

/*

2061

1562

* These reproduce what we would get without ARGP_NO_HELP

2062

1563

*/

2068

1569

argp_state_help(state, state->out_stream,

2069

1570

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2070

1571

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

2071

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

1572

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

2072

1573

exit(argp_err_exit_status);

2073

1574

break;

2074

1575

default:

2101

1602

{

2102

1603

/* Work around Debian bug #633582:

2103

1604

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

2104

2105

/* Re-raise privileges */

2106

ret_errno = raise_privileges();

2107

if(ret_errno != 0){

2108

errno = ret_errno;

2109

perror_plus("Failed to raise privileges");

2110

} else {

2111

struct stat st;

2112

2113

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

2114

int seckey_fd = open(seckey, O_RDONLY);

2115

if(seckey_fd == -1){

2116

perror_plus("open");

2117

} else {

2118

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

2119

if(ret == -1){

2120

perror_plus("fstat");

2121

} else {

2122

if(S_ISREG(st.st_mode)

2123

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

2124

ret = fchown(seckey_fd, uid, gid);

2125

if(ret == -1){

2126

perror_plus("fchown");

2127

}

2128

}

2129

}

2130

TEMP_FAILURE_RETRY(close(seckey_fd));

2131

}

2132

}

2133

2134

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

2135

int pubkey_fd = open(pubkey, O_RDONLY);

2136

if(pubkey_fd == -1){

2137

perror_plus("open");

2138

} else {

2139

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

2140

if(ret == -1){

2141

perror_plus("fstat");

2142

} else {

2143

if(S_ISREG(st.st_mode)

2144

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

2145

ret = fchown(pubkey_fd, uid, gid);

2146

if(ret == -1){

2147

perror_plus("fchown");

2148

}

2149

}

2150

}

2151

TEMP_FAILURE_RETRY(close(pubkey_fd));

2152

}

2153

}

2154

2155

/* Lower privileges */

2156

ret_errno = lower_privileges();

2157

if(ret_errno != 0){

2158

errno = ret_errno;

2159

perror_plus("Failed to lower privileges");

2160

}

2161

}

2162

}

2163

2164

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

2165

{

2166

char *interface = NULL;

2167

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

2168

interface))){

2169

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

2170

and if_nametoindex(interface) == 0){

2171

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

2172

fprintf_plus(stderr, "Not using nonexisting interface"

2173

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

2174

}

2175

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

2176

interface = NULL;

2177

}

2178

}

2179

}

2180

2181

/* Run network hooks */

2182

{

2183

if(mc.interfaces != NULL){

2184

interfaces_hooks = malloc(mc.interfaces_size);

2185

if(interfaces_hooks == NULL){

2186

perror_plus("malloc");

1605

struct stat st;

1606

1607

/* Re-raise priviliges */

1608

errno = 0;

1609

ret = seteuid(0);

1610

if(ret == -1){

1611

perror_plus("seteuid");

1612

}

1613

1614

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

1615

int seckey_fd = open(seckey, O_RDONLY);

1616

if(seckey_fd == -1){

1617

perror_plus("open");

1618

} else {

1619

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

1620

if(ret == -1){

1621

perror_plus("fstat");

1622

} else {

1623

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

1624

ret = fchown(seckey_fd, uid, gid);

1625

if(ret == -1){

1626

perror_plus("fchown");

1627

}

1628

}

1629

}

1630

TEMP_FAILURE_RETRY(close(seckey_fd));

1631

}

1632

}

1633

1634

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

1635

int pubkey_fd = open(pubkey, O_RDONLY);

1636

if(pubkey_fd == -1){

1637

perror_plus("open");

1638

} else {

1639

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

1640

if(ret == -1){

1641

perror_plus("fstat");

1642

} else {

1643

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

1644

ret = fchown(pubkey_fd, uid, gid);

1645

if(ret == -1){

1646

perror_plus("fchown");

1647

}

1648

}

1649

}

1650

TEMP_FAILURE_RETRY(close(pubkey_fd));

1651

}

1652

}

1653

1654

/* Lower privileges */

1655

errno = 0;

1656

ret = seteuid(uid);

1657

if(ret == -1){

1658

perror_plus("seteuid");

1659

}

1660

}

1661

1662

/* Find network hooks and run them */

1663

{

1664

struct dirent **direntries;

1665

struct dirent *direntry;

1666

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

1667

alphasort);

1668

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

1669

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

1670

direntry = direntries[0];

1671

char *fullname = NULL;

1672

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

1673

direntry->d_name);

1674

if(ret < 0){

1675

perror_plus("asprintf");

1676

continue;

1677

}

1678

pid_t hook_pid = fork();

1679

if(hook_pid == 0){

1680

/* Child */

1681

dup2(devnull, STDIN_FILENO);

1682

close(devnull);

1683

dup2(STDERR_FILENO, STDOUT_FILENO);

1684

setenv("DEVICE", interface, 1);

1685

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

1686

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

1687

/* setenv( XXX more here */

1688

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

1689

perror_plus("execl");

1690

}

1691

free(fullname);

1692

if(quit_now){

2187

1693

goto end;

2188

1694

}

2189

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

2190

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

2191

1695

}

2192

run_network_hooks("start", interfaces_hooks != NULL ?

2193

interfaces_hooks : "", delay);

1696

close(devnull);

2194

1697

}

2195

1698

2196

1699

if(not debug){

2197

1700

avahi_set_log_function(empty_log);

2198

1701

}

2199

1702

1703

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

1704

struct dirent **direntries;

1705

ret = scandir(sys_class_net, &direntries, good_interface,

1706

alphasort);

1707

if(ret >= 1){

1708

/* Pick the first good interface */

1709

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

1710

if(debug){

1711

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

1712

}

1713

if(interface == NULL){

1714

perror_plus("malloc");

1715

free(direntries);

1716

exitcode = EXIT_FAILURE;

1717

goto end;

1718

}

1719

free(direntries);

1720

} else {

1721

free(direntries);

1722

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

1723

exitcode = EXIT_FAILURE;

1724

goto end;

1725

}

1726

}

1727

2200

1728

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

2201

1729

from the signal handler */

2202

1730

/* Initialize the pseudo-RNG for Avahi */

2203

1731

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

2204

simple_poll = avahi_simple_poll_new();

2205

if(simple_poll == NULL){

2206

fprintf_plus(stderr,

2207

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

1732

mc.simple_poll = avahi_simple_poll_new();

1733

if(mc.simple_poll == NULL){

1734

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

2208

1735

exitcode = EX_UNAVAILABLE;

2209

1736

goto end;

2210

1737

}

2272

1799

}

2273

1800

}

2274

1801

2275

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

2276

if(mc.interfaces == NULL){

2277

struct dirent **direntries = NULL;

2278

/* Look for any good interfaces */

2279

ret = scandir(sys_class_net, &direntries, good_interface,

2280

alphasort);

2281

if(ret >= 1){

2282

/* Add all found interfaces to interfaces list */

2283

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

2284

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

2285

direntries[i]->d_name);

2286

if(ret_errno != 0){

2287

errno = ret_errno;

2288

perror_plus("argz_add");

2289

free(direntries[i]);

2290

continue;

2291

}

2292

if(debug){

2293

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

2294

direntries[i]->d_name);

2295

}

2296

free(direntries[i]);

2297

}

2298

free(direntries);

1802

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

1803

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

1804

if_index = (AvahiIfIndex) if_nametoindex(interface);

1805

if(if_index == 0){

1806

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

1807

exitcode = EX_UNAVAILABLE;

1808

goto end;

1809

}

1810

1811

if(quit_now){

1812

goto end;

1813

}

1814

1815

/* Re-raise priviliges */

1816

errno = 0;

1817

ret = seteuid(0);

1818

if(ret == -1){

1819

perror_plus("seteuid");

1820

}

1821

1822

#ifdef __linux__

1823

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1824

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

1825

ret = klogctl(8, NULL, 5);

1826

bool restore_loglevel = true;

1827

if(ret == -1){

1828

restore_loglevel = false;

1829

perror_plus("klogctl");

1830

}

1831

#endif /* __linux__ */

1832

1833

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1834

if(sd < 0){

1835

perror_plus("socket");

1836

exitcode = EX_OSERR;

1837

#ifdef __linux__

1838

if(restore_loglevel){

1839

ret = klogctl(7, NULL, 0);

1840

if(ret == -1){

1841

perror_plus("klogctl");

1842

}

1843

}

1844

#endif /* __linux__ */

1845

/* Lower privileges */

1846

errno = 0;

1847

ret = seteuid(uid);

1848

if(ret == -1){

1849

perror_plus("seteuid");

1850

}

1851

goto end;

1852

}

1853

strcpy(network.ifr_name, interface);

1854

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

1855

if(ret == -1){

1856

perror_plus("ioctl SIOCGIFFLAGS");

1857

#ifdef __linux__

1858

if(restore_loglevel){

1859

ret = klogctl(7, NULL, 0);

1860

if(ret == -1){

1861

perror_plus("klogctl");

1862

}

1863

}

1864

#endif /* __linux__ */

1865

exitcode = EX_OSERR;

1866

/* Lower privileges */

1867

errno = 0;

1868

ret = seteuid(uid);

1869

if(ret == -1){

1870

perror_plus("seteuid");

1871

}

1872

goto end;

1873

}

1874

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

1875

network.ifr_flags |= IFF_UP;

1876

take_down_interface = true;

1877

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

1878

if(ret == -1){

1879

take_down_interface = false;

1880

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1881

exitcode = EX_OSERR;

1882

#ifdef __linux__

1883

if(restore_loglevel){

1884

ret = klogctl(7, NULL, 0);

1885

if(ret == -1){

1886

perror_plus("klogctl");

1887

}

1888

}

1889

#endif /* __linux__ */

1890

/* Lower privileges */

1891

errno = 0;

1892

ret = seteuid(uid);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

goto end;

1897

}

1898

}

1899

/* Sleep checking until interface is running.

1900

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

1901

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

1902

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

1903

if(ret == -1){

1904

perror_plus("ioctl SIOCGIFFLAGS");

1905

} else if(network.ifr_flags & IFF_RUNNING){

1906

break;

1907

}

1908

struct timespec sleeptime = { .tv_nsec = 250000000 };

1909

ret = nanosleep(&sleeptime, NULL);

1910

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

1911

perror_plus("nanosleep");

1912

}

1913

}

1914

if(not take_down_interface){

1915

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

1916

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

1917

if(ret == -1){

1918

perror_plus("close");

1919

}

1920

}

1921

#ifdef __linux__

1922

if(restore_loglevel){

1923

/* Restores kernel loglevel to default */

1924

ret = klogctl(7, NULL, 0);

1925

if(ret == -1){

1926

perror_plus("klogctl");

1927

}

1928

}

1929

#endif /* __linux__ */

1930

/* Lower privileges */

1931

errno = 0;

1932

if(take_down_interface){

1933

/* Lower privileges */

1934

ret = seteuid(uid);

1935

if(ret == -1){

1936

perror_plus("seteuid");

1937

}

2299

1938

} else {

2300

if(ret == 0){

2301

free(direntries);

2302

}

2303

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

2304

exitcode = EXIT_FAILURE;

2305

goto end;

2306

}

2307

}

2308

2309

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

2310

{

2311

char *interface = NULL;

2312

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

2313

interface))){

2314

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

2315

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

2316

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

2317

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

2318

interface);

2319

interface = NULL;

2320

while((interface = argz_next(mc.interfaces,

2321

mc.interfaces_size, interface))){

2322

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

2323

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

2324

interface);

2325

interface = NULL;

2326

}

2327

}

2328

break;

2329

}

2330

bool interface_was_up = interface_is_up(interface);

2331

errno = bring_up_interface(interface, delay);

2332

if(not interface_was_up){

2333

if(errno != 0){

2334

perror_plus("Failed to bring up interface");

2335

} else {

2336

errno = argz_add(&interfaces_to_take_down,

2337

&interfaces_to_take_down_size,

2338

interface);

2339

if(errno != 0){

2340

perror_plus("argz_add");

2341

}

2342

}

2343

}

2344

}

2345

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

2346

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

2347

}

2348

}

2349

2350

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

2351

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

2352

if(debug){

2353

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

2354

mc.interfaces);

2355

}

2356

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

1939

/* Lower privileges permanently */

1940

ret = setuid(uid);

1941

if(ret == -1){

1942

perror_plus("setuid");

1943

}

1944

}

2357

1945

}

2358

1946

2359

1947

if(quit_now){

2360

1948

goto end;

2361

1949

}

2362

1950

2363

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

1951

ret = init_gnutls_global(pubkey, seckey);

2364

1952

if(ret == -1){

2365

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

1953

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

2366

1954

exitcode = EX_UNAVAILABLE;

2367

1955

goto end;

2368

1956

} else {

2373

1961

goto end;

2374

1962

}

2375

1963

2376

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

2377

tempdir = mkdtemp(run_tempdir);

2378

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

2379

if(debug){

2380

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

2381

run_tempdir, old_tempdir);

2382

}

2383

tempdir = mkdtemp(old_tempdir);

2384

}

2385

if(tempdir == NULL){

1964

if(mkdtemp(tempdir) == NULL){

2386

1965

perror_plus("mkdtemp");

2387

1966

goto end;

2388

1967

}

1968

tempdir_created = true;

2389

1969

2390

1970

if(quit_now){

2391

1971

goto end;

2392

1972

}

2393

1973

2394

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

2395

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

1974

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

1975

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

2396

1976

exitcode = EX_UNAVAILABLE;

2397

1977

goto end;

2398

1978

} else {

2407

1987

/* Connect directly, do not use Zeroconf */

2408

1988

/* (Mainly meant for debugging) */

2409

1989

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

2410

2411

1990

if(address == NULL){

2412

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

1991

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

2413

1992

exitcode = EX_USAGE;

2414

1993

goto end;

2415

1994

}

2418

1997

goto end;

2419

1998

}

2420

1999

2421

in_port_t port;

2000

uint16_t port;

2422

2001

errno = 0;

2423

2002

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

2424

2003

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

2425

or tmpmax != (in_port_t)tmpmax){

2426

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

2004

or tmpmax != (uint16_t)tmpmax){

2005

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

2427

2006

exitcode = EX_USAGE;

2428

2007

goto end;

2429

2008

}

2430

2009

2431

2010

if(quit_now){

2432

2011

goto end;

2433

2012

}

2434

2013

2435

port = (in_port_t)tmpmax;

2014

port = (uint16_t)tmpmax;

2436

2015

*address = '\0';

2437

2016

/* Colon in address indicates IPv6 */

2438

2017

int af;

2454

2033

}

2455

2034

2456

2035

while(not quit_now){

2457

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

2458

&mc);

2036

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

2459

2037

if(quit_now or ret == 0){

2460

2038

break;

2461

2039

}

2462

2040

if(debug){

2463

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

2464

(int)retry_interval);

2041

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

2042

(int)retry_interval);

2465

2043

}

2466

sleep((unsigned int)retry_interval);

2044

sleep((int)retry_interval);

2467

2045

}

2468

2046

2469

if(not quit_now){

2047

if (not quit_now){

2470

2048

exitcode = EXIT_SUCCESS;

2471

2049

}

2472

2050

2487

2065

config.publish_domain = 0;

2488

2066

2489

2067

/* Allocate a new server */

2490

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2491

&config, NULL, NULL, &ret_errno);

2068

mc.server = avahi_server_new(avahi_simple_poll_get

2069

(mc.simple_poll), &config, NULL,

2070

NULL, &error);

2492

2071

2493

2072

/* Free the Avahi configuration data */

2494

2073

avahi_server_config_free(&config);

2496

2075

2497

2076

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

2498

2077

if(mc.server == NULL){

2499

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

2500

avahi_strerror(ret_errno));

2078

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

2079

avahi_strerror(error));

2501

2080

exitcode = EX_UNAVAILABLE;

2502

2081

goto end;

2503

2082

}

2509

2088

/* Create the Avahi service browser */

2510

2089

sb = avahi_s_service_browser_new(mc.server, if_index,

2511

2090

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2512

NULL, 0, browse_callback,

2513

(void *)&mc);

2091

NULL, 0, browse_callback, NULL);

2514

2092

if(sb == NULL){

2515

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

2516

avahi_strerror(avahi_server_errno(mc.server)));

2093

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

2094

avahi_strerror(avahi_server_errno(mc.server)));

2517

2095

exitcode = EX_UNAVAILABLE;

2518

2096

goto end;

2519

2097

}

2525

2103

/* Run the main loop */

2526

2104

2527

2105

if(debug){

2528

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

2106

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

2529

2107

}

2530

2531

ret = avahi_loop_with_timeout(simple_poll,

2532

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

2108

2109

ret = avahi_loop_with_timeout(mc.simple_poll,

2110

(int)(retry_interval * 1000));

2533

2111

if(debug){

2534

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

2535

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

2112

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

2113

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

2536

2114

}

2537

2115

2538

2116

end:

2539

2117

2540

2118

if(debug){

2541

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

2119

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

2542

2120

}

2543

2121

2544

2122

/* Cleanup things */

2545

free(mc.interfaces);

2546

2547

2123

if(sb != NULL)

2548

2124

avahi_s_service_browser_free(sb);

2549

2125

2550

2126

if(mc.server != NULL)

2551

2127

avahi_server_free(mc.server);

2552

2128

2553

if(simple_poll != NULL)

2554

avahi_simple_poll_free(simple_poll);

2129

if(mc.simple_poll != NULL)

2130

avahi_simple_poll_free(mc.simple_poll);

2555

2131

2556

2132

if(gnutls_initialized){

2557

2133

gnutls_certificate_free_credentials(mc.cred);

2562

2138

if(gpgme_initialized){

2563

2139

gpgme_release(mc.ctx);

2564

2140

}

2565

2141

2566

2142

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

2567

2143

has seen */

2568

2144

if(mc.current_server != NULL){

2569

2145

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

2570

2146

while(mc.current_server != NULL){

2571

2147

server *next = mc.current_server->next;

2572

#ifdef __GNUC__

2573

#pragma GCC diagnostic push

2574

#pragma GCC diagnostic ignored "-Wcast-qual"

2575

#endif

2576

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

2577

#ifdef __GNUC__

2578

#pragma GCC diagnostic pop

2579

#endif

2580

2148

free(mc.current_server);

2581

2149

mc.current_server = next;

2582

2150

}

2583

2151

}

2584

2152

2585

/* Re-raise privileges */

2586

{

2587

ret_errno = raise_privileges();

2588

if(ret_errno != 0){

2589

errno = ret_errno;

2590

perror_plus("Failed to raise privileges");

2591

} else {

2592

2593

/* Run network hooks */

2594

run_network_hooks("stop", interfaces_hooks != NULL ?

2595

interfaces_hooks : "", delay);

2596

2597

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

2598

{

2599

char *interface = NULL;

2600

while((interface=argz_next(interfaces_to_take_down,

2601

interfaces_to_take_down_size,

2602

interface))){

2603

ret_errno = take_down_interface(interface);

2604

if(ret_errno != 0){

2605

errno = ret_errno;

2606

perror_plus("Failed to take down interface");

2607

}

2608

}

2609

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

2610

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

2611

" down\n");

2612

}

2613

}

2153

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

2154

2155

/* Take down the network interface */

2156

if(take_down_interface){

2157

/* Re-raise priviliges */

2158

errno = 0;

2159

ret = seteuid(0);

2160

if(ret == -1){

2161

perror_plus("seteuid");

2614

2162

}

2615

2616

ret_errno = lower_privileges_permanently();

2617

if(ret_errno != 0){

2618

errno = ret_errno;

2619

perror_plus("Failed to lower privileges permanently");

2163

if(geteuid() == 0){

2164

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

2165

if(ret == -1){

2166

perror_plus("ioctl SIOCGIFFLAGS");

2167

} else if(network.ifr_flags & IFF_UP) {

2168

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

2169

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

2170

if(ret == -1){

2171

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2172

}

2173

}

2174

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

2175

if(ret == -1){

2176

perror_plus("close");

2177

}

2178

/* Lower privileges permanently */

2179

errno = 0;

2180

ret = setuid(uid);

2181

if(ret == -1){

2182

perror_plus("setuid");

2183

}

2620

2184

}

2621

2185

}

2622

2186

2623

free(interfaces_to_take_down);

2624

free(interfaces_hooks);

2625

2626

2187

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

2627

if(tempdir != NULL){

2188

if(tempdir_created){

2628

2189

struct dirent **direntries = NULL;

2629

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

2630

O_NOFOLLOW));

2631

if(tempdir_fd == -1){

2632

perror_plus("open");

2633

} else {

2634

#ifdef __GLIBC__

2635

#if __GLIBC_PREREQ(2, 15)

2636

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

2637

notdotentries, alphasort);

2638

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

2639

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

2640

alphasort);

2641

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

2642

#else /* not __GLIBC__ */

2643

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

2644

alphasort);

2645

#endif /* not __GLIBC__ */

2646

if(numentries >= 0){

2647

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

2648

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

2649

if(ret == -1){

2650

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

2651

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

2652

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

2653

}

2654

free(direntries[i]);

2655

}

2656

2657

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

2658

free(direntries);

2659

if(numentries == -1){

2660

perror_plus("scandir");

2661

}

2662

ret = rmdir(tempdir);

2663

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

2664

perror_plus("rmdir");

2665

}

2190

struct dirent *direntry = NULL;

2191

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

2192

alphasort);

2193

if (numentries > 0){

2194

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

2195

direntry = direntries[i];

2196

char *fullname = NULL;

2197

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

2198

direntry->d_name);

2199

if(ret < 0){

2200

perror_plus("asprintf");

2201

continue;

2202

}

2203

ret = remove(fullname);

2204

if(ret == -1){

2205

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

2206

strerror(errno));

2207

}

2208

free(fullname);

2666

2209

}

2667

TEMP_FAILURE_RETRY(close(tempdir_fd));

2210

}

2211

2212

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

2213

free(direntries);

2214

if (numentries == -1){

2215

perror_plus("scandir");

2216

}

2217

ret = rmdir(tempdir);

2218

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

2219

perror_plus("rmdir");

2668

2220

}

2669

2221

}

2670

2222