/mandos/trunk : revision 237.4.49

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

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*

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* Everything else is

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*

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

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

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* along with this program. If not, see

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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

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

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stdout, ferror(), remove() */

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

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stdout, ferror() */

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

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

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

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strtof(), abort() */

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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strtoimax() */

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

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

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

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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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*/

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

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

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setgid(), pause() */

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

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

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unlinkat() */

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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118

init_gnutls_session(),

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119

GNUTLS_* */

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120

#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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125

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

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133

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

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134

#define SECKEY "seckey.txt"

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135

#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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139

static const char mandos_protocol_version[] = "1";

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

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

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

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

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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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149

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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162

AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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164

unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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166

const char *priority;

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167

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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172

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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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/* global so signal handler can reach it*/

174

AvahiSimplePoll *simple_poll;

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175

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sig_atomic_t quit_now = 0;

150

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int signal_received = 0;

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/* Function to use when printing errors */

180

void perror_plus(const char *print_text){

181

int e = errno;

182

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

183

program_invocation_short_name);

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errno = e;

185

perror(print_text);

186

}

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188

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

189

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

190

va_list ap;

191

va_start (ap, format);

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193

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

194

program_invocation_short_name));

195

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

196

}

197

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/*

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199

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

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200

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

155

201

* "buffer_length" is how much is already used.

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202

*/

203

__attribute__((nonnull, warn_unused_result))

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204

size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

205

size_t buffer_capacity){

159

206

if(buffer_length + BUFFER_SIZE > buffer_capacity){

160

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

161

if(buffer == NULL){

207

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

215

*buffer = new_buf;

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216

buffer_capacity += BUFFER_SIZE;

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217

}

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return buffer_capacity;

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219

}

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

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__attribute__((nonnull, warn_unused_result))

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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 ret;

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

227

if(new_server == NULL){

228

perror_plus("malloc");

229

return false;

230

}

231

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

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.port = port,

233

.if_index = if_index,

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.af = af };

235

if(new_server->ip == NULL){

236

perror_plus("strdup");

237

free(new_server);

238

return false;

239

}

240

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

241

if(ret == -1){

242

perror_plus("clock_gettime");

243

free(new_server->ip);

244

free(new_server);

245

return false;

246

}

247

/* Special case of first server */

248

if(*current_server == NULL){

249

new_server->next = new_server;

250

new_server->prev = new_server;

251

*current_server = new_server;

252

} else {

253

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

254

new_server->next = *current_server;

255

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

256

new_server->prev->next = new_server;

257

(*current_server)->prev = new_server;

258

}

259

return true;

260

}

261

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/*

170

263

* Initialize GPGME.

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264

*/

172

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

265

__attribute__((nonnull, warn_unused_result))

266

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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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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275

*/

181

bool import_key(const char *filename){

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bool import_key(const char * const filename){

182

277

int ret;

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int fd;

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gpgme_data_t pgp_data;

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

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282

if(fd == -1){

188

perror("open");

283

perror_plus("open");

189

284

return false;

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285

}

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286

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rc = gpgme_data_new_from_fd(&pgp_data, fd);

193

288

if(rc != GPG_ERR_NO_ERROR){

194

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

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gpgme_strsource(rc), gpgme_strerror(rc));

289

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

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}

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293

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rc = gpgme_op_import(mc.ctx, pgp_data);

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

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if(rc != GPG_ERR_NO_ERROR){

201

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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

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gpgme_strsource(rc), gpgme_strerror(rc));

203

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return false;

204

299

}

205

300

206

301

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

207

302

if(ret == -1){

208

perror("close");

303

perror_plus("close");

209

304

}

210

305

gpgme_data_release(pgp_data);

211

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return true;

212

307

}

213

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214

309

if(debug){

215

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

310

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

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311

}

217

312

218

313

/* Init GPGME */

219

314

gpgme_check_version(NULL);

220

315

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

221

316

if(rc != GPG_ERR_NO_ERROR){

222

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

223

gpgme_strsource(rc), gpgme_strerror(rc));

317

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

318

gpgme_strsource(rc), gpgme_strerror(rc));

224

319

return false;

225

320

}

226

321

227

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

322

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

228

323

rc = gpgme_get_engine_info(&engine_info);

229

324

if(rc != GPG_ERR_NO_ERROR){

230

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

231

gpgme_strsource(rc), gpgme_strerror(rc));

325

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

326

gpgme_strsource(rc), gpgme_strerror(rc));

232

327

return false;

233

328

}

234

329

while(engine_info != NULL){

240

335

engine_info = engine_info->next;

241

336

}

242

337

if(engine_info == NULL){

243

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

338

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

339

tempdir);

244

340

return false;

245

341

}

246

342

247

343

/* Create new GPGME "context" */

248

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

344

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

249

345

if(rc != GPG_ERR_NO_ERROR){

250

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

251

gpgme_strsource(rc), gpgme_strerror(rc));

346

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

347

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

348

gpgme_strerror(rc));

252

349

return false;

253

350

}

254

351

263

360

* Decrypt OpenPGP data.

264

361

* Returns -1 on error

265

362

*/

363

__attribute__((nonnull, warn_unused_result))

266

364

static ssize_t pgp_packet_decrypt(const char *cryptotext,

267

365

size_t crypto_size,

268

char **plaintext){

366

char **plaintext,

367

mandos_context *mc){

269

368

gpgme_data_t dh_crypto, dh_plain;

270

369

gpgme_error_t rc;

271

370

ssize_t ret;

273

372

ssize_t plaintext_length = 0;

274

373

275

374

if(debug){

276

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

375

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

277

376

}

278

377

279

378

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

280

379

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

281

380

0);

282

381

if(rc != GPG_ERR_NO_ERROR){

283

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

284

gpgme_strsource(rc), gpgme_strerror(rc));

382

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

383

gpgme_strsource(rc), gpgme_strerror(rc));

285

384

return -1;

286

385

}

287

386

288

387

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

289

388

rc = gpgme_data_new(&dh_plain);

290

389

if(rc != GPG_ERR_NO_ERROR){

291

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

292

gpgme_strsource(rc), gpgme_strerror(rc));

390

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

391

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

392

gpgme_strsource(rc), gpgme_strerror(rc));

293

393

gpgme_data_release(dh_crypto);

294

394

return -1;

295

395

}

296

396

297

397

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

298

398

data buffer */

299

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

399

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

300

400

if(rc != GPG_ERR_NO_ERROR){

301

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

302

gpgme_strsource(rc), gpgme_strerror(rc));

401

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

402

gpgme_strsource(rc), gpgme_strerror(rc));

303

403

plaintext_length = -1;

304

404

if(debug){

305

405

gpgme_decrypt_result_t result;

306

result = gpgme_op_decrypt_result(mc.ctx);

406

result = gpgme_op_decrypt_result(mc->ctx);

307

407

if(result == NULL){

308

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

408

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

309

409

} else {

310

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

311

result->unsupported_algorithm);

312

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

313

result->wrong_key_usage);

410

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

411

result->unsupported_algorithm);

412

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

413

result->wrong_key_usage);

314

414

if(result->file_name != NULL){

315

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

415

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

316

416

}

317

417

gpgme_recipient_t recipient;

318

418

recipient = result->recipients;

319

419

while(recipient != NULL){

320

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

321

gpgme_pubkey_algo_name(recipient->pubkey_algo));

322

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

323

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

324

recipient->status == GPG_ERR_NO_SECKEY

325

? "No" : "Yes");

420

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

421

gpgme_pubkey_algo_name

422

(recipient->pubkey_algo));

423

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

424

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

425

recipient->status == GPG_ERR_NO_SECKEY

426

? "No" : "Yes");

326

427

recipient = recipient->next;

327

428

}

328

429

}

331

432

}

332

433

333

434

if(debug){

334

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

435

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

335

436

}

336

437

337

438

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

338

439

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

339

perror("gpgme_data_seek");

440

perror_plus("gpgme_data_seek");

340

441

plaintext_length = -1;

341

442

goto decrypt_end;

342

443

}

344

445

*plaintext = NULL;

345

446

while(true){

346

447

plaintext_capacity = incbuffer(plaintext,

347

(size_t)plaintext_length,

348

plaintext_capacity);

448

(size_t)plaintext_length,

449

plaintext_capacity);

349

450

if(plaintext_capacity == 0){

350

perror("incbuffer");

351

plaintext_length = -1;

352

goto decrypt_end;

451

perror_plus("incbuffer");

452

plaintext_length = -1;

453

goto decrypt_end;

353

454

}

354

455

355

456

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

360

461

break;

361

462

}

362

463

if(ret < 0){

363

perror("gpgme_data_read");

464

perror_plus("gpgme_data_read");

364

465

plaintext_length = -1;

365

466

goto decrypt_end;

366

467

}

368

469

}

369

470

370

471

if(debug){

371

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

472

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

372

473

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

373

474

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

374

475

}

385

486

return plaintext_length;

386

487

}

387

488

388

static const char * safer_gnutls_strerror(int value){

389

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

390

-Wunreachable-code */

489

__attribute__((warn_unused_result))

490

static const char *safer_gnutls_strerror(int value){

491

const char *ret = gnutls_strerror(value);

391

492

if(ret == NULL)

392

493

ret = "(unknown)";

393

494

return ret;

394

495

}

395

496

396

497

/* GnuTLS log function callback */

498

__attribute__((nonnull))

397

499

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

398

500

const char* string){

399

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

501

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

400

502

}

401

503

504

__attribute__((nonnull, warn_unused_result))

402

505

static int init_gnutls_global(const char *pubkeyfilename,

403

const char *seckeyfilename){

506

const char *seckeyfilename,

507

mandos_context *mc){

404

508

int ret;

405

509

406

510

if(debug){

407

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

511

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

408

512

}

409

513

410

514

ret = gnutls_global_init();

411

515

if(ret != GNUTLS_E_SUCCESS){

412

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

413

safer_gnutls_strerror(ret));

516

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

517

safer_gnutls_strerror(ret));

414

518

return -1;

415

519

}

416

520

423

527

}

424

528

425

529

/* OpenPGP credentials */

426

gnutls_certificate_allocate_credentials(&mc.cred);

530

ret = gnutls_certificate_allocate_credentials(&mc->cred);

427

531

if(ret != GNUTLS_E_SUCCESS){

428

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

429

from

430

-Wunreachable-code

431

*/

432

safer_gnutls_strerror(ret));

532

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

533

safer_gnutls_strerror(ret));

433

534

gnutls_global_deinit();

434

535

return -1;

435

536

}

436

537

437

538

if(debug){

438

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

439

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

440

seckeyfilename);

539

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

540

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

541

pubkeyfilename,

542

seckeyfilename);

441

543

}

442

544

443

545

ret = gnutls_certificate_set_openpgp_key_file

444

(mc.cred, pubkeyfilename, seckeyfilename,

546

(mc->cred, pubkeyfilename, seckeyfilename,

445

547

GNUTLS_OPENPGP_FMT_BASE64);

446

548

if(ret != GNUTLS_E_SUCCESS){

447

fprintf(stderr,

448

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

449

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

450

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

451

safer_gnutls_strerror(ret));

549

fprintf_plus(stderr,

550

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

551

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

552

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

553

safer_gnutls_strerror(ret));

452

554

goto globalfail;

453

555

}

454

556

455

557

/* GnuTLS server initialization */

456

ret = gnutls_dh_params_init(&mc.dh_params);

558

ret = gnutls_dh_params_init(&mc->dh_params);

457

559

if(ret != GNUTLS_E_SUCCESS){

458

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

459

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

560

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

561

" initialization: %s\n",

562

safer_gnutls_strerror(ret));

460

563

goto globalfail;

461

564

}

462

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

565

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

463

566

if(ret != GNUTLS_E_SUCCESS){

464

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

465

safer_gnutls_strerror(ret));

567

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

568

safer_gnutls_strerror(ret));

466

569

goto globalfail;

467

570

}

468

571

469

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

572

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

470

573

471

574

return 0;

472

575

473

576

globalfail:

474

577

475

gnutls_certificate_free_credentials(mc.cred);

578

gnutls_certificate_free_credentials(mc->cred);

476

579

gnutls_global_deinit();

477

gnutls_dh_params_deinit(mc.dh_params);

580

gnutls_dh_params_deinit(mc->dh_params);

478

581

return -1;

479

582

}

480

583

481

static int init_gnutls_session(gnutls_session_t *session){

584

__attribute__((nonnull, warn_unused_result))

585

static int init_gnutls_session(gnutls_session_t *session,

586

mandos_context *mc){

482

587

int ret;

483

588

/* GnuTLS session creation */

484

589

do {

488

593

}

489

594

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

490

595

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

596

fprintf_plus(stderr,

597

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

598

safer_gnutls_strerror(ret));

493

599

}

494

600

495

601

{

496

602

const char *err;

497

603

do {

498

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

604

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

499

605

if(quit_now){

500

606

gnutls_deinit(*session);

501

607

return -1;

502

608

}

503

609

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

504

610

if(ret != GNUTLS_E_SUCCESS){

505

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

506

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

507

safer_gnutls_strerror(ret));

611

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

612

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

613

safer_gnutls_strerror(ret));

508

614

gnutls_deinit(*session);

509

615

return -1;

510

616

}

512

618

513

619

do {

514

620

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

515

mc.cred);

621

mc->cred);

516

622

if(quit_now){

517

623

gnutls_deinit(*session);

518

624

return -1;

519

625

}

520

626

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

521

627

if(ret != GNUTLS_E_SUCCESS){

522

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

523

safer_gnutls_strerror(ret));

628

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

629

safer_gnutls_strerror(ret));

524

630

gnutls_deinit(*session);

525

631

return -1;

526

632

}

528

634

/* ignore client certificate if any. */

529

635

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

530

636

531

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

637

gnutls_dh_set_prime_bits(*session, mc->dh_bits);

532

638

533

639

return 0;

534

640

}

538

644

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

539

645

540

646

/* Called when a Mandos server is found */

541

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

647

__attribute__((nonnull, warn_unused_result))

648

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

542

649

AvahiIfIndex if_index,

543

int af){

650

int af, mandos_context *mc){

544

651

int ret, tcp_sd = -1;

545

652

ssize_t sret;

546

union {

547

struct sockaddr_in in;

548

struct sockaddr_in6 in6;

549

} to;

653

struct sockaddr_storage to;

550

654

char *buffer = NULL;

551

655

char *decrypted_buffer = NULL;

552

656

size_t buffer_length = 0;

571

675

pf = PF_INET;

572

676

break;

573

677

default:

574

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

678

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

575

679

errno = EINVAL;

576

680

return -1;

577

681

}

578

682

579

ret = init_gnutls_session(&session);

683

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

684

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

685

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

686

bool match = false;

687

{

688

char *interface = NULL;

689

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

690

interface))){

691

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

692

match = true;

693

break;

694

}

695

}

696

}

697

if(not match){

698

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

699

connect to the server */

700

if(debug){

701

char interface[IF_NAMESIZE];

702

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

703

perror_plus("if_indextoname");

704

} else {

705

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

706

" \"%s\"\n",

707

if_indextoname((unsigned int)if_index,

708

interface));

709

}

710

}

711

return -1;

712

}

713

}

714

715

ret = init_gnutls_session(&session, mc);

580

716

if(ret != 0){

581

717

return -1;

582

718

}

583

719

584

720

if(debug){

585

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

586

"\n", ip, port);

721

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

722

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

587

723

}

588

724

589

725

tcp_sd = socket(pf, SOCK_STREAM, 0);

590

726

if(tcp_sd < 0){

591

727

int e = errno;

592

perror("socket");

728

perror_plus("socket");

593

729

errno = e;

594

730

goto mandos_end;

595

731

}

601

737

602

738

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

603

739

if(af == AF_INET6){

604

to.in6.sin6_family = (sa_family_t)af;

605

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

740

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

741

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

606

742

} else { /* IPv4 */

607

to.in.sin_family = (sa_family_t)af;

608

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

743

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

744

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

609

745

}

610

746

if(ret < 0 ){

611

747

int e = errno;

612

perror("inet_pton");

748

perror_plus("inet_pton");

613

749

errno = e;

614

750

goto mandos_end;

615

751

}

616

752

if(ret == 0){

617

753

int e = errno;

618

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

754

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

619

755

errno = e;

620

756

goto mandos_end;

621

757

}

622

758

if(af == AF_INET6){

623

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

624

-Wconversion and

625

-Wunreachable-code */

626

627

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

628

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

629

-Wunreachable-code*/

759

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

760

if(IN6_IS_ADDR_LINKLOCAL

761

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

630

762

if(if_index == AVAHI_IF_UNSPEC){

631

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

632

" without a network interface\n");

763

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

764

" incomplete without a network interface\n");

633

765

errno = EINVAL;

634

766

goto mandos_end;

635

767

}

636

768

/* Set the network interface number as scope */

637

to.in6.sin6_scope_id = (uint32_t)if_index;

769

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

638

770

}

639

771

} else {

640

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

641

-Wconversion and

642

-Wunreachable-code */

772

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

643

773

}

644

774

645

775

if(quit_now){

651

781

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

652

782

char interface[IF_NAMESIZE];

653

783

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

654

perror("if_indextoname");

784

perror_plus("if_indextoname");

655

785

} else {

656

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

657

ip, interface, port);

786

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

787

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

658

788

}

659

789

} else {

660

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

661

port);

790

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

791

ip, (uintmax_t)port);

662

792

}

663

793

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

664

794

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

665

const char *pcret;

666

795

if(af == AF_INET6){

667

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

668

sizeof(addrstr));

796

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

797

sizeof(struct sockaddr_in6),

798

addrstr, sizeof(addrstr), NULL, 0,

799

NI_NUMERICHOST);

669

800

} else {

670

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

671

sizeof(addrstr));

801

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

802

sizeof(struct sockaddr_in),

803

addrstr, sizeof(addrstr), NULL, 0,

804

NI_NUMERICHOST);

672

805

}

673

if(pcret == NULL){

674

perror("inet_ntop");

675

} else {

676

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

677

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

678

}

806

if(ret == EAI_SYSTEM){

807

perror_plus("getnameinfo");

808

} else if(ret != 0) {

809

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

810

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

811

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

679

812

}

680

813

}

681

814

685

818

}

686

819

687

820

if(af == AF_INET6){

688

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

821

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

822

sizeof(struct sockaddr_in6));

689

823

} else {

690

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

824

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

825

sizeof(struct sockaddr_in));

691

826

}

692

827

if(ret < 0){

693

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

828

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

694

829

int e = errno;

695

perror("connect");

830

perror_plus("connect");

696

831

errno = e;

697

832

}

698

833

goto mandos_end;

708

843

while(true){

709

844

size_t out_size = strlen(out);

710

845

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

711

out_size - written));

846

out_size - written));

712

847

if(ret == -1){

713

848

int e = errno;

714

perror("write");

849

perror_plus("write");

715

850

errno = e;

716

851

goto mandos_end;

717

852

}

734

869

}

735

870

736

871

if(debug){

737

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

872

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

738

873

}

739

874

740

875

if(quit_now){

742

877

goto mandos_end;

743

878

}

744

879

745

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

880

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

881

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

882

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

883

gnutls_transport_set_ptr(session,

884

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

746

885

747

886

if(quit_now){

748

887

errno = EINTR;

759

898

760

899

if(ret != GNUTLS_E_SUCCESS){

761

900

if(debug){

762

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

901

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

763

902

gnutls_perror(ret);

764

903

}

765

904

errno = EPROTO;

769

908

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

770

909

771

910

if(debug){

772

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

773

ip);

911

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

912

" %s\n", ip);

774

913

}

775

914

776

915

while(true){

781

920

}

782

921

783

922

buffer_capacity = incbuffer(&buffer, buffer_length,

784

buffer_capacity);

923

buffer_capacity);

785

924

if(buffer_capacity == 0){

786

925

int e = errno;

787

perror("incbuffer");

926

perror_plus("incbuffer");

788

927

errno = e;

789

928

goto mandos_end;

790

929

}

814

953

}

815

954

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

816

955

if(ret < 0){

817

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

956

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

957

"***\n");

818

958

gnutls_perror(ret);

819

959

errno = EPROTO;

820

960

goto mandos_end;

821

961

}

822

962

break;

823

963

default:

824

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

825

" encrypted session with Mandos server\n");

964

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

965

" encrypted session with Mandos server\n");

826

966

gnutls_bye(session, GNUTLS_SHUT_RDWR);

827

967

errno = EIO;

828

968

goto mandos_end;

833

973

}

834

974

835

975

if(debug){

836

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

976

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

837

977

}

838

978

839

979

if(quit_now){

851

991

852

992

if(buffer_length > 0){

853

993

ssize_t decrypted_buffer_size;

854

decrypted_buffer_size = pgp_packet_decrypt(buffer,

855

buffer_length,

856

&decrypted_buffer);

994

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

995

&decrypted_buffer, mc);

857

996

if(decrypted_buffer_size >= 0){

858

997

859

998

written = 0;

869

1008

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

870

1009

int e = errno;

871

1010

if(debug){

872

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

873

strerror(errno));

1011

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

1012

strerror(errno));

874

1013

}

875

1014

errno = e;

876

1015

goto mandos_end;

895

1034

if(e == 0){

896

1035

e = errno;

897

1036

}

898

perror("close");

1037

perror_plus("close");

899

1038

}

900

1039

gnutls_deinit(session);

1040

errno = e;

901

1041

if(quit_now){

902

e = EINTR;

1042

errno = EINTR;

903

1043

retval = -1;

904

1044

}

905

errno = e;

906

1045

}

907

1046

return retval;

908

1047

}

909

1048

1049

__attribute__((nonnull))

910

1050

static void resolve_callback(AvahiSServiceResolver *r,

911

1051

AvahiIfIndex interface,

912

1052

AvahiProtocol proto,

920

1060

AVAHI_GCC_UNUSED AvahiStringList *txt,

921

1061

AVAHI_GCC_UNUSED AvahiLookupResultFlags

922

1062

flags,

923

AVAHI_GCC_UNUSED void* userdata){

924

assert(r);

1063

void *mc){

1064

if(r == NULL){

1065

return;

1066

}

925

1067

926

1068

/* Called whenever a service has been resolved successfully or

927

1069

timed out */

933

1075

switch(event){

934

1076

default:

935

1077

case AVAHI_RESOLVER_FAILURE:

936

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

937

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

938

avahi_strerror(avahi_server_errno(mc.server)));

1078

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

1079

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

1080

domain,

1081

avahi_strerror(avahi_server_errno

1082

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

939

1083

break;

940

1084

941

1085

case AVAHI_RESOLVER_FOUND:

943

1087

char ip[AVAHI_ADDRESS_STR_MAX];

944

1088

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

945

1089

if(debug){

946

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

947

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

948

ip, (intmax_t)interface, port);

1090

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

1091

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

1092

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

949

1093

}

950

int ret = start_mandos_communication(ip, port, interface,

951

avahi_proto_to_af(proto));

1094

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

1095

interface,

1096

avahi_proto_to_af(proto),

1097

mc);

952

1098

if(ret == 0){

953

avahi_simple_poll_quit(mc.simple_poll);

1099

avahi_simple_poll_quit(simple_poll);

1100

} else {

1101

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

1102

avahi_proto_to_af(proto),

1103

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

1104

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

1105

" list\n", name);

1106

}

954

1107

}

955

1108

}

956

1109

}

966

1119

const char *domain,

967

1120

AVAHI_GCC_UNUSED AvahiLookupResultFlags

968

1121

flags,

969

AVAHI_GCC_UNUSED void* userdata){

970

assert(b);

1122

void *mc){

1123

if(b == NULL){

1124

return;

1125

}

971

1126

972

1127

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

973

1128

is removed from the LAN */

980

1135

default:

981

1136

case AVAHI_BROWSER_FAILURE:

982

1137

983

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

984

avahi_strerror(avahi_server_errno(mc.server)));

985

avahi_simple_poll_quit(mc.simple_poll);

1138

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

1139

avahi_strerror(avahi_server_errno

1140

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

1141

avahi_simple_poll_quit(simple_poll);

986

1142

return;

987

1143

988

1144

case AVAHI_BROWSER_NEW:

991

1147

the callback function is called the Avahi server will free the

992

1148

resolver for us. */

993

1149

994

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

995

name, type, domain, protocol, 0,

996

resolve_callback, NULL) == NULL)

997

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

998

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

1150

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

1151

interface, protocol, name, type,

1152

domain, protocol, 0,

1153

resolve_callback, mc) == NULL)

1154

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

1155

" %s\n", name,

1156

avahi_strerror(avahi_server_errno

1157

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

999

1158

break;

1000

1159

1001

1160

case AVAHI_BROWSER_REMOVE:

1004

1163

case AVAHI_BROWSER_ALL_FOR_NOW:

1005

1164

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1006

1165

if(debug){

1007

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

1166

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

1167

" searching...\n");

1008

1168

}

1009

1169

break;

1010

1170

}

1011

1171

}

1012

1172

1013

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

1173

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

1014

1174

static void handle_sigterm(int sig){

1015

1175

if(quit_now){

1016

1176

return;

1018

1178

quit_now = 1;

1019

1179

signal_received = sig;

1020

1180

int old_errno = errno;

1021

if(mc.simple_poll != NULL){

1022

avahi_simple_poll_quit(mc.simple_poll);

1181

/* set main loop to exit */

1182

if(simple_poll != NULL){

1183

avahi_simple_poll_quit(simple_poll);

1023

1184

}

1024

1185

errno = old_errno;

1025

1186

}

1026

1187

1188

__attribute__((nonnull, warn_unused_result))

1189

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

1190

int ret;

1191

error_t ret_errno;

1192

1193

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

1194

if(s < 0){

1195

ret_errno = errno;

1196

perror_plus("socket");

1197

errno = ret_errno;

1198

return false;

1199

}

1200

strcpy(ifr->ifr_name, ifname);

1201

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1202

if(ret == -1){

1203

if(debug){

1204

ret_errno = errno;

1205

perror_plus("ioctl SIOCGIFFLAGS");

1206

errno = ret_errno;

1207

}

1208

return false;

1209

}

1210

return true;

1211

}

1212

1213

__attribute__((nonnull, warn_unused_result))

1214

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

1215

1216

/* Reject the loopback device */

1217

if(ifr->ifr_flags & IFF_LOOPBACK){

1218

if(debug){

1219

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

1220

ifname);

1221

}

1222

return false;

1223

}

1224

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

1225

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

1226

if(debug){

1227

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

1228

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

1229

}

1230

return true;

1231

}

1232

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

1233

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

1234

if(debug){

1235

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1236

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

1237

}

1238

return false;

1239

}

1240

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

1241

if(ifr->ifr_flags & IFF_NOARP){

1242

if(debug){

1243

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

1244

ifname);

1245

}

1246

return false;

1247

}

1248

1249

/* Accept this device */

1250

if(debug){

1251

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

1252

}

1253

return true;

1254

}

1255

1027

1256

/*

1028

1257

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

1029

1258

* corresponds to an acceptable network device.

1030

1259

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

1031

1260

*/

1261

__attribute__((nonnull, warn_unused_result))

1032

1262

int good_interface(const struct dirent *if_entry){

1033

ssize_t ssret;

1034

char *flagname = NULL;

1035

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

1036

if_entry->d_name);

1037

if(ret < 0){

1038

perror("asprintf");

1039

return 0;

1040

}

1041

1263

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

1042

1264

return 0;

1043

1265

}

1044

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

1045

if(flags_fd == -1){

1046

perror("open");

1047

return 0;

1048

}

1049

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

1050

/* read line from flags_fd */

1051

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

1052

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

1053

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

1054

if(flagstring == NULL){

1055

perror("malloc");

1056

close(flags_fd);

1057

return 0;

1058

}

1059

while(to_read > 0){

1060

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

1061

(size_t)to_read));

1062

if(ssret == -1){

1063

perror("read");

1064

free(flagstring);

1065

close(flags_fd);

1066

return 0;

1067

}

1068

to_read -= ssret;

1069

if(ssret == 0){

1266

1267

struct ifreq ifr;

1268

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

1269

if(debug){

1270

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

1271

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

1272

}

1273

return 0;

1274

}

1275

1276

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

1277

return 0;

1278

}

1279

return 1;

1280

}

1281

1282

/*

1283

* This function determines if a network interface is up.

1284

*/

1285

__attribute__((nonnull, warn_unused_result))

1286

bool interface_is_up(const char *interface){

1287

struct ifreq ifr;

1288

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

1289

if(debug){

1290

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

1291

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

1292

}

1293

return false;

1294

}

1295

1296

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

1297

}

1298

1299

/*

1300

* This function determines if a network interface is running

1301

*/

1302

__attribute__((nonnull, warn_unused_result))

1303

bool interface_is_running(const char *interface){

1304

struct ifreq ifr;

1305

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

1306

if(debug){

1307

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

1308

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

1309

}

1310

return false;

1311

}

1312

1313

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

1314

}

1315

1316

__attribute__((nonnull, pure, warn_unused_result))

1317

int notdotentries(const struct dirent *direntry){

1318

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

1319

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

1320

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

1321

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

1322

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

1323

return 0;

1324

}

1325

return 1;

1326

}

1327

1328

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

1329

__attribute__((nonnull, warn_unused_result))

1330

int runnable_hook(const struct dirent *direntry){

1331

int ret;

1332

size_t sret;

1333

struct stat st;

1334

1335

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

1336

/* Empty name? */

1337

return 0;

1338

}

1339

1340

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

1341

"abcdefghijklmnopqrstuvwxyz"

1342

"0123456789"

1343

"_.-");

1344

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

1345

/* Contains non-allowed characters */

1346

if(debug){

1347

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

1348

direntry->d_name);

1349

}

1350

return 0;

1351

}

1352

1353

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

1354

if(ret == -1){

1355

if(debug){

1356

perror_plus("Could not stat hook");

1357

}

1358

return 0;

1359

}

1360

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

1361

/* Not a regular file */

1362

if(debug){

1363

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

1364

direntry->d_name);

1365

}

1366

return 0;

1367

}

1368

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

1369

/* Not executable */

1370

if(debug){

1371

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

1372

direntry->d_name);

1373

}

1374

return 0;

1375

}

1376

if(debug){

1377

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

1378

direntry->d_name);

1379

}

1380

return 1;

1381

}

1382

1383

__attribute__((nonnull, warn_unused_result))

1384

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1385

mandos_context *mc){

1386

int ret;

1387

struct timespec now;

1388

struct timespec waited_time;

1389

intmax_t block_time;

1390

1391

while(true){

1392

if(mc->current_server == NULL){

1393

if(debug){

1394

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

1395

" No timeout!\n");

1396

}

1397

ret = avahi_simple_poll_iterate(s, -1);

1398

} else {

1399

if(debug){

1400

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

1401

" it, or wait\n");

1402

}

1403

/* the current time */

1404

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1405

if(ret == -1){

1406

perror_plus("clock_gettime");

1407

return -1;

1408

}

1409

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

1410

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

1411

waited_time.tv_sec = (now.tv_sec

1412

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

1413

waited_time.tv_nsec = (now.tv_nsec

1414

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

1415

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

1416

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

1417

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

1418

block_time = ((retry_interval

1419

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

1420

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

1421

1422

if(debug){

1423

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

1424

block_time);

1425

}

1426

1427

if(block_time <= 0){

1428

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

1429

mc->current_server->port,

1430

mc->current_server->if_index,

1431

mc->current_server->af, mc);

1432

if(ret == 0){

1433

avahi_simple_poll_quit(s);

1434

return 0;

1435

}

1436

ret = clock_gettime(CLOCK_MONOTONIC,

1437

&mc->current_server->last_seen);

1438

if(ret == -1){

1439

perror_plus("clock_gettime");

1440

return -1;

1441

}

1442

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

1443

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

1444

servers, but don't block */

1445

}

1446

1447

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

1448

}

1449

if(ret != 0){

1450

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

1451

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

1452

}

1453

}

1454

}

1455

}

1456

1457

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

1458

__attribute__((warn_unused_result))

1459

error_t raise_privileges(void){

1460

error_t old_errno = errno;

1461

error_t ret_errno = 0;

1462

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

1463

ret_errno = errno;

1464

}

1465

errno = old_errno;

1466

return ret_errno;

1467

}

1468

1469

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

1470

__attribute__((warn_unused_result))

1471

error_t raise_privileges_permanently(void){

1472

error_t old_errno = errno;

1473

error_t ret_errno = raise_privileges();

1474

if(ret_errno != 0){

1475

errno = old_errno;

1476

return ret_errno;

1477

}

1478

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

1479

ret_errno = errno;

1480

}

1481

errno = old_errno;

1482

return ret_errno;

1483

}

1484

1485

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

1486

__attribute__((warn_unused_result))

1487

error_t lower_privileges(void){

1488

error_t old_errno = errno;

1489

error_t ret_errno = 0;

1490

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

1491

ret_errno = errno;

1492

}

1493

errno = old_errno;

1494

return ret_errno;

1495

}

1496

1497

/* Lower privileges permanently */

1498

__attribute__((warn_unused_result))

1499

error_t lower_privileges_permanently(void){

1500

error_t old_errno = errno;

1501

error_t ret_errno = 0;

1502

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

1503

ret_errno = errno;

1504

}

1505

errno = old_errno;

1506

return ret_errno;

1507

}

1508

1509

__attribute__((nonnull))

1510

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

1511

const float delay){

1512

struct dirent **direntries = NULL;

1513

if(hookdir_fd == -1){

1514

hookdir_fd = open(hookdir, O_RDONLY);

1515

if(hookdir_fd == -1){

1516

if(errno == ENOENT){

1517

if(debug){

1518

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

1519

" found\n", hookdir);

1520

}

1521

} else {

1522

perror_plus("open");

1523

}

1524

return;

1525

}

1526

}

1527

#ifdef __GLIBC__

1528

#if __GLIBC_PREREQ(2, 15)

1529

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

1530

runnable_hook, alphasort);

1531

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

1532

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

1533

alphasort);

1534

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

1535

#else /* not __GLIBC__ */

1536

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

1537

alphasort);

1538

#endif /* not __GLIBC__ */

1539

if(numhooks == -1){

1540

perror_plus("scandir");

1541

return;

1542

}

1543

struct dirent *direntry;

1544

int ret;

1545

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

1546

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

1547

direntry = direntries[i];

1548

if(debug){

1549

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

1550

direntry->d_name);

1551

}

1552

pid_t hook_pid = fork();

1553

if(hook_pid == 0){

1554

/* Child */

1555

/* Raise privileges */

1556

errno = raise_privileges_permanently();

1557

if(errno != 0){

1558

perror_plus("Failed to raise privileges");

1559

_exit(EX_NOPERM);

1560

}

1561

/* Set group */

1562

errno = 0;

1563

ret = setgid(0);

1564

if(ret == -1){

1565

perror_plus("setgid");

1566

_exit(EX_NOPERM);

1567

}

1568

/* Reset supplementary groups */

1569

errno = 0;

1570

ret = setgroups(0, NULL);

1571

if(ret == -1){

1572

perror_plus("setgroups");

1573

_exit(EX_NOPERM);

1574

}

1575

ret = dup2(devnull, STDIN_FILENO);

1576

if(ret == -1){

1577

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

1578

_exit(EX_OSERR);

1579

}

1580

ret = close(devnull);

1581

if(ret == -1){

1582

perror_plus("close");

1583

_exit(EX_OSERR);

1584

}

1585

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1586

if(ret == -1){

1587

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

1588

_exit(EX_OSERR);

1589

}

1590

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

1591

if(ret == -1){

1592

perror_plus("setenv");

1593

_exit(EX_OSERR);

1594

}

1595

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

1596

if(ret == -1){

1597

perror_plus("setenv");

1598

_exit(EX_OSERR);

1599

}

1600

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

1601

if(ret == -1){

1602

perror_plus("setenv");

1603

_exit(EX_OSERR);

1604

}

1605

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

1606

if(ret == -1){

1607

perror_plus("setenv");

1608

_exit(EX_OSERR);

1609

}

1610

char *delaystring;

1611

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

1612

if(ret == -1){

1613

perror_plus("asprintf");

1614

_exit(EX_OSERR);

1615

}

1616

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

1617

if(ret == -1){

1618

free(delaystring);

1619

perror_plus("setenv");

1620

_exit(EX_OSERR);

1621

}

1622

free(delaystring);

1623

if(connect_to != NULL){

1624

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

1625

if(ret == -1){

1626

perror_plus("setenv");

1627

_exit(EX_OSERR);

1628

}

1629

}

1630

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

1631

if(hook_fd == -1){

1632

perror_plus("openat");

1633

_exit(EXIT_FAILURE);

1634

}

1635

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

1636

perror_plus("close");

1637

_exit(EXIT_FAILURE);

1638

}

1639

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

1640

environ) == -1){

1641

perror_plus("fexecve");

1642

_exit(EXIT_FAILURE);

1643

}

1644

} else {

1645

int status;

1646

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

1647

perror_plus("waitpid");

1648

continue;

1649

}

1650

if(WIFEXITED(status)){

1651

if(WEXITSTATUS(status) != 0){

1652

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

1653

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

1654

WEXITSTATUS(status));

1655

continue;

1656

}

1657

} else if(WIFSIGNALED(status)){

1658

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

1659

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

1660

WTERMSIG(status));

1661

continue;

1662

} else {

1663

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

1664

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

1665

continue;

1666

}

1667

}

1668

if(debug){

1669

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

1670

direntry->d_name);

1671

}

1672

}

1673

free(direntries);

1674

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

1675

perror_plus("close");

1676

} else {

1677

hookdir_fd = -1;

1678

}

1679

close(devnull);

1680

}

1681

1682

__attribute__((nonnull, warn_unused_result))

1683

error_t bring_up_interface(const char *const interface,

1684

const float delay){

1685

error_t old_errno = errno;

1686

int ret;

1687

struct ifreq network;

1688

unsigned int if_index = if_nametoindex(interface);

1689

if(if_index == 0){

1690

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

1691

errno = old_errno;

1692

return ENXIO;

1693

}

1694

1695

if(quit_now){

1696

errno = old_errno;

1697

return EINTR;

1698

}

1699

1700

if(not interface_is_up(interface)){

1701

error_t ret_errno = 0, ioctl_errno = 0;

1702

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

1703

ret_errno = errno;

1704

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

1705

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

1706

errno = old_errno;

1707

return ret_errno;

1708

}

1709

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

1710

1711

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

1712

if(sd == -1){

1713

ret_errno = errno;

1714

perror_plus("socket");

1715

errno = old_errno;

1716

return ret_errno;

1717

}

1718

1719

if(quit_now){

1720

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

1721

if(ret == -1){

1722

perror_plus("close");

1723

}

1724

errno = old_errno;

1725

return EINTR;

1726

}

1727

1728

if(debug){

1729

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

1730

interface);

1731

}

1732

1733

/* Raise privileges */

1734

ret_errno = raise_privileges();

1735

if(ret_errno != 0){

1736

errno = ret_errno;

1737

perror_plus("Failed to raise privileges");

1738

}

1739

1740

#ifdef __linux__

1741

int ret_linux;

1742

bool restore_loglevel = false;

1743

if(ret_errno == 0){

1744

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1745

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

1746

ret_linux = klogctl(8, NULL, 5);

1747

if(ret_linux == -1){

1748

perror_plus("klogctl");

1749

} else {

1750

restore_loglevel = true;

1751

}

1752

}

1753

#endif /* __linux__ */

1754

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

1755

ioctl_errno = errno;

1756

#ifdef __linux__

1757

if(restore_loglevel){

1758

ret_linux = klogctl(7, NULL, 0);

1759

if(ret_linux == -1){

1760

perror_plus("klogctl");

1761

}

1762

}

1763

#endif /* __linux__ */

1764

1765

/* If raise_privileges() succeeded above */

1766

if(ret_errno == 0){

1767

/* Lower privileges */

1768

ret_errno = lower_privileges();

1769

if(ret_errno != 0){

1770

errno = ret_errno;

1771

perror_plus("Failed to lower privileges");

1772

}

1773

}

1774

1775

/* Close the socket */

1776

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

1777

if(ret == -1){

1778

perror_plus("close");

1779

}

1780

1781

if(ret_setflags == -1){

1782

errno = ioctl_errno;

1783

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1784

errno = old_errno;

1785

return ioctl_errno;

1786

}

1787

} else if(debug){

1788

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

1789

interface);

1790

}

1791

1792

/* Sleep checking until interface is running.

1793

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

1794

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

1795

if(interface_is_running(interface)){

1070

1796

break;

1071

1797

}

1072

}

1073

close(flags_fd);

1074

intmax_t tmpmax;

1075

char *tmp;

1076

errno = 0;

1077

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

1078

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

1079

and not (isspace(*tmp)))

1080

or tmpmax != (ifreq_flags)tmpmax){

1081

if(debug){

1082

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

1083

flagstring, if_entry->d_name);

1084

}

1085

free(flagstring);

1086

return 0;

1087

}

1088

free(flagstring);

1089

ifreq_flags flags = (ifreq_flags)tmpmax;

1090

/* Reject the loopback device */

1091

if(flags & IFF_LOOPBACK){

1092

if(debug){

1093

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

1094

if_entry->d_name);

1095

}

1096

return 0;

1097

}

1098

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

1099

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

1100

if(debug){

1101

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

1102

if_entry->d_name);

1103

}

1104

return 1;

1105

}

1106

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

1107

if(not (flags & IFF_BROADCAST)){

1108

if(debug){

1109

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

1110

if_entry->d_name);

1111

}

1112

return 0;

1113

}

1114

/* Accept this device */

1115

if(debug){

1116

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

1117

if_entry->d_name);

1118

}

1119

return 1;

1798

struct timespec sleeptime = { .tv_nsec = 250000000 };

1799

ret = nanosleep(&sleeptime, NULL);

1800

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

1801

perror_plus("nanosleep");

1802

}

1803

}

1804

1805

errno = old_errno;

1806

return 0;

1807

}

1808

1809

__attribute__((nonnull, warn_unused_result))

1810

error_t take_down_interface(const char *const interface){

1811

error_t old_errno = errno;

1812

struct ifreq network;

1813

unsigned int if_index = if_nametoindex(interface);

1814

if(if_index == 0){

1815

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

1816

errno = old_errno;

1817

return ENXIO;

1818

}

1819

if(interface_is_up(interface)){

1820

error_t ret_errno = 0, ioctl_errno = 0;

1821

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

1822

ret_errno = errno;

1823

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

1824

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

1825

errno = old_errno;

1826

return ret_errno;

1827

}

1828

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

1829

1830

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

1831

if(sd == -1){

1832

ret_errno = errno;

1833

perror_plus("socket");

1834

errno = old_errno;

1835

return ret_errno;

1836

}

1837

1838

if(debug){

1839

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

1840

interface);

1841

}

1842

1843

/* Raise privileges */

1844

ret_errno = raise_privileges();

1845

if(ret_errno != 0){

1846

errno = ret_errno;

1847

perror_plus("Failed to raise privileges");

1848

}

1849

1850

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

1851

ioctl_errno = errno;

1852

1853

/* If raise_privileges() succeeded above */

1854

if(ret_errno == 0){

1855

/* Lower privileges */

1856

ret_errno = lower_privileges();

1857

if(ret_errno != 0){

1858

errno = ret_errno;

1859

perror_plus("Failed to lower privileges");

1860

}

1861

}

1862

1863

/* Close the socket */

1864

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

1865

if(ret == -1){

1866

perror_plus("close");

1867

}

1868

1869

if(ret_setflags == -1){

1870

errno = ioctl_errno;

1871

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1872

errno = old_errno;

1873

return ioctl_errno;

1874

}

1875

} else if(debug){

1876

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

1877

interface);

1878

}

1879

1880

errno = old_errno;

1881

return 0;

1120

1882

}

1121

1883

1122

1884

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

1885

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

1886

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

1887

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

1888

.interfaces = NULL, .interfaces_size = 0 };

1123

1889

AvahiSServiceBrowser *sb = NULL;

1124

int error;

1890

error_t ret_errno;

1125

1891

int ret;

1126

1892

intmax_t tmpmax;

1127

1893

char *tmp;

1128

1894

int exitcode = EXIT_SUCCESS;

1129

const char *interface = "";

1130

struct ifreq network;

1131

int sd = -1;

1132

bool take_down_interface = false;

1133

uid_t uid;

1134

gid_t gid;

1135

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

1136

bool tempdir_created = false;

1895

char *interfaces_to_take_down = NULL;

1896

size_t interfaces_to_take_down_size = 0;

1897

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

1898

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

1899

char *tempdir = NULL;

1137

1900

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1138

1901

const char *seckey = PATHDIR "/" SECKEY;

1139

1902

const char *pubkey = PATHDIR "/" PUBKEY;

1903

char *interfaces_hooks = NULL;

1140

1904

1141

1905

bool gnutls_initialized = false;

1142

1906

bool gpgme_initialized = false;

1143

1907

float delay = 2.5f;

1908

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

1909

retrying the same server again */

1144

1910

1145

1911

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1146

1912

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1152

1918

errno = 0;

1153

1919

ret = setgid(gid);

1154

1920

if(ret == -1){

1155

perror("setgid");

1921

perror_plus("setgid");

1156

1922

}

1157

1923

1158

1924

/* Lower user privileges (temporarily) */

1159

1925

errno = 0;

1160

1926

ret = seteuid(uid);

1161

1927

if(ret == -1){

1162

perror("seteuid");

1928

perror_plus("seteuid");

1163

1929

}

1164

1930

1165

1931

if(quit_now){

1200

1966

.arg = "SECONDS",

1201

1967

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

1202

1968

.group = 2 },

1969

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

1970

.arg = "SECONDS",

1971

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

1972

.group = 2 },

1973

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

1974

.arg = "DIR",

1975

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

1976

.group = 2 },

1203

1977

/*

1204

1978

* These reproduce what we would get without ARGP_NO_HELP

1205

1979

*/

1223

1997

connect_to = arg;

1224

1998

break;

1225

1999

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

1226

interface = arg;

2000

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

2001

arg, (int)',');

2002

if(ret_errno != 0){

2003

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

2004

}

1227

2005

break;

1228

2006

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

1229

2007

seckey = arg;

1249

2027

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

1250

2028

argp_error(state, "Bad delay");

1251

2029

}

2030

case 132: /* --retry */

2031

errno = 0;

2032

retry_interval = strtod(arg, &tmp);

2033

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

2034

or (retry_interval * 1000) > INT_MAX

2035

or retry_interval < 0){

2036

argp_error(state, "Bad retry interval");

2037

}

2038

break;

2039

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

2040

hookdir = arg;

1252

2041

break;

1253

2042

/*

1254

2043

* These reproduce what we would get without ARGP_NO_HELP

1261

2050

argp_state_help(state, state->out_stream,

1262

2051

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1263

2052

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

1264

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

2053

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

1265

2054

exit(argp_err_exit_status);

1266

2055

break;

1267

2056

default:

1282

2071

case ENOMEM:

1283

2072

default:

1284

2073

errno = ret;

1285

perror("argp_parse");

2074

perror_plus("argp_parse");

1286

2075

exitcode = EX_OSERR;

1287

2076

goto end;

1288

2077

case EINVAL:

1290

2079

goto end;

1291

2080

}

1292

2081

}

2082

2083

{

2084

/* Work around Debian bug #633582:

2085

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

2086

2087

/* Re-raise privileges */

2088

ret_errno = raise_privileges();

2089

if(ret_errno != 0){

2090

errno = ret_errno;

2091

perror_plus("Failed to raise privileges");

2092

} else {

2093

struct stat st;

2094

2095

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

2096

int seckey_fd = open(seckey, O_RDONLY);

2097

if(seckey_fd == -1){

2098

perror_plus("open");

2099

} else {

2100

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

2101

if(ret == -1){

2102

perror_plus("fstat");

2103

} else {

2104

if(S_ISREG(st.st_mode)

2105

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

2106

ret = fchown(seckey_fd, uid, gid);

2107

if(ret == -1){

2108

perror_plus("fchown");

2109

}

2110

}

2111

}

2112

TEMP_FAILURE_RETRY(close(seckey_fd));

2113

}

2114

}

2115

2116

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

2117

int pubkey_fd = open(pubkey, O_RDONLY);

2118

if(pubkey_fd == -1){

2119

perror_plus("open");

2120

} else {

2121

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

2122

if(ret == -1){

2123

perror_plus("fstat");

2124

} else {

2125

if(S_ISREG(st.st_mode)

2126

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

2127

ret = fchown(pubkey_fd, uid, gid);

2128

if(ret == -1){

2129

perror_plus("fchown");

2130

}

2131

}

2132

}

2133

TEMP_FAILURE_RETRY(close(pubkey_fd));

2134

}

2135

}

2136

2137

/* Lower privileges */

2138

ret_errno = lower_privileges();

2139

if(ret_errno != 0){

2140

errno = ret_errno;

2141

perror_plus("Failed to lower privileges");

2142

}

2143

}

2144

}

2145

2146

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

2147

{

2148

char *interface = NULL;

2149

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

2150

interface))){

2151

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

2152

and if_nametoindex(interface) == 0){

2153

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

2154

fprintf_plus(stderr, "Not using nonexisting interface"

2155

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

2156

}

2157

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

2158

interface = NULL;

2159

}

2160

}

2161

}

2162

2163

/* Run network hooks */

2164

{

2165

if(mc.interfaces != NULL){

2166

interfaces_hooks = malloc(mc.interfaces_size);

2167

if(interfaces_hooks == NULL){

2168

perror_plus("malloc");

2169

goto end;

2170

}

2171

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

2172

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

2173

}

2174

run_network_hooks("start", interfaces_hooks != NULL ?

2175

interfaces_hooks : "", delay);

2176

}

1293

2177

1294

2178

if(not debug){

1295

2179

avahi_set_log_function(empty_log);

1296

2180

}

1297

1298

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

1299

struct dirent **direntries;

1300

ret = scandir(sys_class_net, &direntries, good_interface,

1301

alphasort);

1302

if(ret >= 1){

1303

/* Pick the first good interface */

1304

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

1305

if(debug){

1306

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

1307

}

1308

if(interface == NULL){

1309

perror("malloc");

1310

free(direntries);

1311

exitcode = EXIT_FAILURE;

1312

goto end;

1313

}

1314

free(direntries);

1315

} else {

1316

free(direntries);

1317

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

1318

exitcode = EXIT_FAILURE;

1319

goto end;

1320

}

1321

}

1322

2181

1323

2182

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

1324

2183

from the signal handler */

1325

2184

/* Initialize the pseudo-RNG for Avahi */

1326

2185

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

1327

mc.simple_poll = avahi_simple_poll_new();

1328

if(mc.simple_poll == NULL){

1329

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

2186

simple_poll = avahi_simple_poll_new();

2187

if(simple_poll == NULL){

2188

fprintf_plus(stderr,

2189

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

1330

2190

exitcode = EX_UNAVAILABLE;

1331

2191

goto end;

1332

2192

}

1334

2194

sigemptyset(&sigterm_action.sa_mask);

1335

2195

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

1336

2196

if(ret == -1){

1337

perror("sigaddset");

2197

perror_plus("sigaddset");

1338

2198

exitcode = EX_OSERR;

1339

2199

goto end;

1340

2200

}

1341

2201

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

1342

2202

if(ret == -1){

1343

perror("sigaddset");

2203

perror_plus("sigaddset");

1344

2204

exitcode = EX_OSERR;

1345

2205

goto end;

1346

2206

}

1347

2207

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

1348

2208

if(ret == -1){

1349

perror("sigaddset");

2209

perror_plus("sigaddset");

1350

2210

exitcode = EX_OSERR;

1351

2211

goto end;

1352

2212

}

1356

2216

*/

1357

2217

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

1358

2218

if(ret == -1){

1359

perror("sigaction");

2219

perror_plus("sigaction");

1360

2220

return EX_OSERR;

1361

2221

}

1362

2222

if(old_sigterm_action.sa_handler != SIG_IGN){

1363

2223

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

1364

2224

if(ret == -1){

1365

perror("sigaction");

2225

perror_plus("sigaction");

1366

2226

exitcode = EX_OSERR;

1367

2227

goto end;

1368

2228

}

1369

2229

}

1370

2230

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

1371

2231

if(ret == -1){

1372

perror("sigaction");

2232

perror_plus("sigaction");

1373

2233

return EX_OSERR;

1374

2234

}

1375

2235

if(old_sigterm_action.sa_handler != SIG_IGN){

1376

2236

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

1377

2237

if(ret == -1){

1378

perror("sigaction");

2238

perror_plus("sigaction");

1379

2239

exitcode = EX_OSERR;

1380

2240

goto end;

1381

2241

}

1382

2242

}

1383

2243

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

1384

2244

if(ret == -1){

1385

perror("sigaction");

2245

perror_plus("sigaction");

1386

2246

return EX_OSERR;

1387

2247

}

1388

2248

if(old_sigterm_action.sa_handler != SIG_IGN){

1389

2249

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

1390

2250

if(ret == -1){

1391

perror("sigaction");

1392

exitcode = EX_OSERR;

1393

goto end;

1394

}

1395

}

1396

1397

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

1398

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

1399

if_index = (AvahiIfIndex) if_nametoindex(interface);

1400

if(if_index == 0){

1401

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

1402

exitcode = EX_UNAVAILABLE;

1403

goto end;

1404

}

1405

1406

if(quit_now){

1407

goto end;

1408

}

1409

1410

/* Re-raise priviliges */

1411

errno = 0;

1412

ret = seteuid(0);

1413

if(ret == -1){

1414

perror("seteuid");

1415

}

1416

1417

#ifdef __linux__

1418

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1419

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

1420

ret = klogctl(8, NULL, 5);

1421

bool restore_loglevel = true;

1422

if(ret == -1){

1423

restore_loglevel = false;

1424

perror("klogctl");

1425

}

1426

#endif /* __linux__ */

1427

1428

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1429

if(sd < 0){

1430

perror("socket");

1431

exitcode = EX_OSERR;

1432

#ifdef __linux__

1433

if(restore_loglevel){

1434

ret = klogctl(7, NULL, 0);

1435

if(ret == -1){

1436

perror("klogctl");

1437

}

1438

}

1439

#endif /* __linux__ */

1440

/* Lower privileges */

1441

errno = 0;

1442

ret = seteuid(uid);

1443

if(ret == -1){

1444

perror("seteuid");

1445

}

1446

goto end;

1447

}

1448

strcpy(network.ifr_name, interface);

1449

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

1450

if(ret == -1){

1451

perror("ioctl SIOCGIFFLAGS");

1452

#ifdef __linux__

1453

if(restore_loglevel){

1454

ret = klogctl(7, NULL, 0);

1455

if(ret == -1){

1456

perror("klogctl");

1457

}

1458

}

1459

#endif /* __linux__ */

1460

exitcode = EX_OSERR;

1461

/* Lower privileges */

1462

errno = 0;

1463

ret = seteuid(uid);

1464

if(ret == -1){

1465

perror("seteuid");

1466

}

1467

goto end;

1468

}

1469

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

1470

network.ifr_flags |= IFF_UP;

1471

take_down_interface = true;

1472

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

1473

if(ret == -1){

1474

take_down_interface = false;

1475

perror("ioctl SIOCSIFFLAGS +IFF_UP");

1476

exitcode = EX_OSERR;

1477

#ifdef __linux__

1478

if(restore_loglevel){

1479

ret = klogctl(7, NULL, 0);

1480

if(ret == -1){

1481

perror("klogctl");

2251

perror_plus("sigaction");

2252

exitcode = EX_OSERR;

2253

goto end;

2254

}

2255

}

2256

2257

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

2258

if(mc.interfaces == NULL){

2259

struct dirent **direntries = NULL;

2260

/* Look for any good interfaces */

2261

ret = scandir(sys_class_net, &direntries, good_interface,

2262

alphasort);

2263

if(ret >= 1){

2264

/* Add all found interfaces to interfaces list */

2265

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

2266

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

2267

direntries[i]->d_name);

2268

if(ret_errno != 0){

2269

errno = ret_errno;

2270

perror_plus("argz_add");

2271

continue;

2272

}

2273

if(debug){

2274

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

2275

direntries[i]->d_name);

2276

}

2277

}

2278

free(direntries);

2279

} else {

2280

if(ret == 0){

2281

free(direntries);

2282

}

2283

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

2284

exitcode = EXIT_FAILURE;

2285

goto end;

2286

}

2287

}

2288

2289

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

2290

{

2291

char *interface = NULL;

2292

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

2293

interface))){

2294

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

2295

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

2296

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

2297

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

2298

interface);

2299

interface = NULL;

2300

while((interface = argz_next(mc.interfaces,

2301

mc.interfaces_size, interface))){

2302

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

2303

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

2304

interface);

2305

interface = NULL;

1482

2306

}

1483

2307

}

1484

#endif /* __linux__ */

1485

/* Lower privileges */

1486

errno = 0;

1487

ret = seteuid(uid);

1488

if(ret == -1){

1489

perror("seteuid");

1490

}

1491

goto end;

1492

}

1493

}

1494

/* sleep checking until interface is running */

1495

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

1496

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

1497

if(ret == -1){

1498

perror("ioctl SIOCGIFFLAGS");

1499

} else if(network.ifr_flags & IFF_RUNNING){

1500

2308

break;

1501

2309

}

1502

struct timespec sleeptime = { .tv_nsec = 250000000 };

1503

ret = nanosleep(&sleeptime, NULL);

1504

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

1505

perror("nanosleep");

1506

}

1507

}

1508

if(not take_down_interface){

1509

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

1510

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

1511

if(ret == -1){

1512

perror("close");

1513

}

1514

}

1515

#ifdef __linux__

1516

if(restore_loglevel){

1517

/* Restores kernel loglevel to default */

1518

ret = klogctl(7, NULL, 0);

1519

if(ret == -1){

1520

perror("klogctl");

1521

}

1522

}

1523

#endif /* __linux__ */

1524

/* Lower privileges */

1525

errno = 0;

1526

if(take_down_interface){

1527

/* Lower privileges */

1528

ret = seteuid(uid);

1529

if(ret == -1){

1530

perror("seteuid");

1531

}

1532

} else {

1533

/* Lower privileges permanently */

1534

ret = setuid(uid);

1535

if(ret == -1){

1536

perror("setuid");

1537

}

1538

}

2310

bool interface_was_up = interface_is_up(interface);

2311

errno = bring_up_interface(interface, delay);

2312

if(not interface_was_up){

2313

if(errno != 0){

2314

perror_plus("Failed to bring up interface");

2315

} else {

2316

errno = argz_add(&interfaces_to_take_down,

2317

&interfaces_to_take_down_size,

2318

interface);

2319

if(errno != 0){

2320

perror_plus("argz_add");

2321

}

2322

}

2323

}

2324

}

2325

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

2326

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

2327

}

2328

}

2329

2330

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

2331

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

2332

if(debug){

2333

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

2334

mc.interfaces);

2335

}

2336

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

1539

2337

}

1540

2338

1541

2339

if(quit_now){

1542

2340

goto end;

1543

2341

}

1544

2342

1545

ret = init_gnutls_global(pubkey, seckey);

2343

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

1546

2344

if(ret == -1){

1547

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

2345

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

1548

2346

exitcode = EX_UNAVAILABLE;

1549

2347

goto end;

1550

2348

} else {

1555

2353

goto end;

1556

2354

}

1557

2355

1558

tempdir_created = true;

1559

if(mkdtemp(tempdir) == NULL){

1560

tempdir_created = false;

1561

perror("mkdtemp");

2356

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

2357

tempdir = mkdtemp(run_tempdir);

2358

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

2359

if(debug){

2360

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

2361

run_tempdir, old_tempdir);

2362

}

2363

tempdir = mkdtemp(old_tempdir);

2364

}

2365

if(tempdir == NULL){

2366

perror_plus("mkdtemp");

1562

2367

goto end;

1563

2368

}

1564

2369

1566

2371

goto end;

1567

2372

}

1568

2373

1569

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

1570

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

2374

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

2375

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

1571

2376

exitcode = EX_UNAVAILABLE;

1572

2377

goto end;

1573

2378

} else {

1582

2387

/* Connect directly, do not use Zeroconf */

1583

2388

/* (Mainly meant for debugging) */

1584

2389

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

2390

1585

2391

if(address == NULL){

1586

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

2392

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

1587

2393

exitcode = EX_USAGE;

1588

2394

goto end;

1589

2395

}

1592

2398

goto end;

1593

2399

}

1594

2400

1595

uint16_t port;

2401

in_port_t port;

1596

2402

errno = 0;

1597

2403

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

1598

2404

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

1599

or tmpmax != (uint16_t)tmpmax){

1600

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

2405

or tmpmax != (in_port_t)tmpmax){

2406

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

1601

2407

exitcode = EX_USAGE;

1602

2408

goto end;

1603

2409

}

1604

2410

1605

2411

if(quit_now){

1606

2412

goto end;

1607

2413

}

1608

2414

1609

port = (uint16_t)tmpmax;

2415

port = (in_port_t)tmpmax;

1610

2416

*address = '\0';

1611

address = connect_to;

1612

2417

/* Colon in address indicates IPv6 */

1613

2418

int af;

1614

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

2419

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

1615

2420

af = AF_INET6;

2421

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

2422

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

2423

{

2424

connect_to++;

2425

address[-1] = '\0';

2426

}

1616

2427

} else {

1617

2428

af = AF_INET;

1618

2429

}

2430

address = connect_to;

1619

2431

1620

2432

if(quit_now){

1621

2433

goto end;

1622

2434

}

1623

2435

1624

2436

while(not quit_now){

1625

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

2437

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

2438

&mc);

1626

2439

if(quit_now or ret == 0){

1627

2440

break;

1628

2441

}

1629

sleep(15);

1630

};

1631

1632

if (not quit_now){

2442

if(debug){

2443

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

2444

(int)retry_interval);

2445

}

2446

sleep((unsigned int)retry_interval);

2447

}

2448

2449

if(not quit_now){

1633

2450

exitcode = EXIT_SUCCESS;

1634

2451

}

1635

2452

1636

2453

goto end;

1637

2454

}

1638

2455

1650

2467

config.publish_domain = 0;

1651

2468

1652

2469

/* Allocate a new server */

1653

mc.server = avahi_server_new(avahi_simple_poll_get

1654

(mc.simple_poll), &config, NULL,

1655

NULL, &error);

2470

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

2471

&config, NULL, NULL, &ret_errno);

1656

2472

1657

2473

/* Free the Avahi configuration data */

1658

2474

avahi_server_config_free(&config);

1660

2476

1661

2477

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

1662

2478

if(mc.server == NULL){

1663

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

1664

avahi_strerror(error));

2479

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

2480

avahi_strerror(ret_errno));

1665

2481

exitcode = EX_UNAVAILABLE;

1666

2482

goto end;

1667

2483

}

1673

2489

/* Create the Avahi service browser */

1674

2490

sb = avahi_s_service_browser_new(mc.server, if_index,

1675

2491

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1676

NULL, 0, browse_callback, NULL);

2492

NULL, 0, browse_callback,

2493

(void *)&mc);

1677

2494

if(sb == NULL){

1678

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

1679

avahi_strerror(avahi_server_errno(mc.server)));

2495

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

2496

avahi_strerror(avahi_server_errno(mc.server)));

1680

2497

exitcode = EX_UNAVAILABLE;

1681

2498

goto end;

1682

2499

}

1688

2505

/* Run the main loop */

1689

2506

1690

2507

if(debug){

1691

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

2508

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

1692

2509

}

1693

2510

1694

avahi_simple_poll_loop(mc.simple_poll);

2511

ret = avahi_loop_with_timeout(simple_poll,

2512

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

2513

if(debug){

2514

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

2515

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

2516

}

1695

2517

1696

2518

end:

1697

2519

1698

2520

if(debug){

1699

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

2521

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

1700

2522

}

1701

2523

1702

2524

/* Cleanup things */

2525

free(mc.interfaces);

2526

1703

2527

if(sb != NULL)

1704

2528

avahi_s_service_browser_free(sb);

1705

2529

1706

2530

if(mc.server != NULL)

1707

2531

avahi_server_free(mc.server);

1708

2532

1709

if(mc.simple_poll != NULL)

1710

avahi_simple_poll_free(mc.simple_poll);

2533

if(simple_poll != NULL)

2534

avahi_simple_poll_free(simple_poll);

1711

2535

1712

2536

if(gnutls_initialized){

1713

2537

gnutls_certificate_free_credentials(mc.cred);

1719

2543

gpgme_release(mc.ctx);

1720

2544

}

1721

2545

1722

/* Take down the network interface */

1723

if(take_down_interface){

1724

/* Re-raise priviliges */

1725

errno = 0;

1726

ret = seteuid(0);

1727

if(ret == -1){

1728

perror("seteuid");

1729

}

1730

if(geteuid() == 0){

1731

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

1732

if(ret == -1){

1733

perror("ioctl SIOCGIFFLAGS");

1734

} else if(network.ifr_flags & IFF_UP) {

1735

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

1736

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

1737

if(ret == -1){

1738

perror("ioctl SIOCSIFFLAGS -IFF_UP");

1739

}

1740

}

1741

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

1742

if(ret == -1){

1743

perror("close");

1744

}

1745

/* Lower privileges permanently */

1746

errno = 0;

1747

ret = setuid(uid);

1748

if(ret == -1){

1749

perror("setuid");

1750

}

1751

}

1752

}

1753

1754

/* Removes the temp directory used by GPGME */

1755

if(tempdir_created){

1756

DIR *d;

1757

struct dirent *direntry;

1758

d = opendir(tempdir);

1759

if(d == NULL){

1760

if(errno != ENOENT){

1761

perror("opendir");

1762

}

1763

} else {

1764

while(true){

1765

direntry = readdir(d);

1766

if(direntry == NULL){

1767

break;

1768

}

1769

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

1770

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

1771

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

1772

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

1773

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

1774

continue;

1775

}

1776

char *fullname = NULL;

1777

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

1778

direntry->d_name);

1779

if(ret < 0){

1780

perror("asprintf");

1781

continue;

1782

}

1783

ret = remove(fullname);

1784

if(ret == -1){

1785

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

1786

strerror(errno));

1787

}

1788

free(fullname);

1789

}

1790

closedir(d);

1791

}

1792

ret = rmdir(tempdir);

1793

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

1794

perror("rmdir");

2546

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

2547

has seen */

2548

if(mc.current_server != NULL){

2549

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

2550

while(mc.current_server != NULL){

2551

server *next = mc.current_server->next;

2552

free(mc.current_server);

2553

mc.current_server = next;

2554

}

2555

}

2556

2557

/* Re-raise privileges */

2558

{

2559

ret_errno = raise_privileges();

2560

if(ret_errno != 0){

2561

errno = ret_errno;

2562

perror_plus("Failed to raise privileges");

2563

} else {

2564

2565

/* Run network hooks */

2566

run_network_hooks("stop", interfaces_hooks != NULL ?

2567

interfaces_hooks : "", delay);

2568

2569

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

2570

{

2571

char *interface = NULL;

2572

while((interface=argz_next(interfaces_to_take_down,

2573

interfaces_to_take_down_size,

2574

interface))){

2575

ret_errno = take_down_interface(interface);

2576

if(ret_errno != 0){

2577

errno = ret_errno;

2578

perror_plus("Failed to take down interface");

2579

}

2580

}

2581

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

2582

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

2583

" down\n");

2584

}

2585

}

2586

}

2587

2588

ret_errno = lower_privileges_permanently();

2589

if(ret_errno != 0){

2590

errno = ret_errno;

2591

perror_plus("Failed to lower privileges permanently");

2592

}

2593

}

2594

2595

free(interfaces_to_take_down);

2596

free(interfaces_hooks);

2597

2598

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

2599

if(tempdir != NULL){

2600

struct dirent **direntries = NULL;

2601

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

2602

O_NOFOLLOW));

2603

if(tempdir_fd == -1){

2604

perror_plus("open");

2605

} else {

2606

#ifdef __GLIBC__

2607

#if __GLIBC_PREREQ(2, 15)

2608

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

2609

notdotentries, alphasort);

2610

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

2611

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

2612

alphasort);

2613

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

2614

#else /* not __GLIBC__ */

2615

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

2616

alphasort);

2617

#endif /* not __GLIBC__ */

2618

if(numentries >= 0){

2619

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

2620

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

2621

if(ret == -1){

2622

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

2623

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

2624

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

2625

}

2626

}

2627

2628

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

2629

free(direntries);

2630

if(numentries == -1){

2631

perror_plus("scandir");

2632

}

2633

ret = rmdir(tempdir);

2634

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

2635

perror_plus("rmdir");

2636

}

2637

}

2638

TEMP_FAILURE_RETRY(close(tempdir_fd));

1795

2639

}

1796

2640

}

1797

2641

1802

2646

&old_sigterm_action,

1803

2647

NULL));

1804

2648

if(ret == -1){

1805

perror("sigaction");

2649

perror_plus("sigaction");

1806

2650

}

1807

2651

do {

1808

2652

ret = raise(signal_received);

1809

2653

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

1810

2654

if(ret != 0){

1811

perror("raise");

2655

perror_plus("raise");

1812

2656

abort();

1813

2657

}

1814

2658

TEMP_FAILURE_RETRY(pause());