/mandos/release : revision 237.17.6

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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 file is part of Mandos.

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*

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* Mandos is free software: you can redistribute it and/or modify it

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* under the terms of the GNU General Public License as published by

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* the Free Software Foundation, either version 3 of the License, or

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* (at your option) any later version.

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*

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* Mandos is distributed in the hope that it will be useful, but

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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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* published by the Free Software Foundation, either version 3 of the

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* License, or (at your option) any later version.

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*

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* This program is distributed in the hope that it will be useful, but

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

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* General Public License for more details.

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*

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* You should have received a copy of the GNU General Public License

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* along with Mandos. If not, see <http://www.gnu.org/licenses/>.

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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@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 /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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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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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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

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

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program_invocation_short_name */

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

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

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*/

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

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

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

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unlinkat() */

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

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setgid(), pause(), _exit() */

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

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

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

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argp_state, struct argp,

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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161

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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perror(print_text);

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}

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

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

212

197

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

225

205

}

226

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

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__attribute__((nonnull, warn_unused_result))

229

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

230

int af, server **current_server){

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bool add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,

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int af){

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int ret;

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

233

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if(new_server == NULL){

240

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.af = af };

241

220

if(new_server->ip == NULL){

242

221

perror_plus("strdup");

243

free(new_server);

244

return false;

245

}

246

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

247

if(ret == -1){

248

perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

251

#pragma GCC diagnostic ignored "-Wcast-qual"

252

#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

256

#endif

257

free(new_server);

258

222

return false;

259

223

}

260

224

/* Special case of first server */

261

if(*current_server == NULL){

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if (mc.current_server == NULL){

262

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new_server->next = new_server;

263

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new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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

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230

} else {

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

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new_server->next = *current_server;

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

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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mc.current_server->prev = new_server;

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}

236

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

237

if(ret == -1){

238

perror_plus("clock_gettime");

239

return false;

271

240

}

272

241

return true;

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}

275

244

/*

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245

* Initialize GPGME.

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246

*/

278

__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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static bool init_gpgme(const char *seckey, const char *pubkey,

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const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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251

252

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/*

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

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*/

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bool import_key(const char * const filename){

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bool import_key(const char *filename){

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int ret;

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int fd;

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gpgme_data_t pgp_data;

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return false;

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}

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

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rc = gpgme_op_import(mc.ctx, pgp_data);

308

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if(rc != GPG_ERR_NO_ERROR){

309

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

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gpgme_strsource(rc), gpgme_strerror(rc));

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return false;

312

279

}

313

{

314

gpgme_import_result_t import_result

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= gpgme_op_import_result(mc->ctx);

316

if((import_result->imported < 1

317

or import_result->not_imported > 0)

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and import_result->unchanged == 0){

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fprintf_plus(stderr, "bad gpgme_op_import_results:\n");

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fprintf_plus(stderr,

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"The total number of considered keys: %d\n",

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import_result->considered);

323

fprintf_plus(stderr,

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"The number of keys without user ID: %d\n",

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import_result->no_user_id);

326

fprintf_plus(stderr,

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"The total number of imported keys: %d\n",

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import_result->imported);

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fprintf_plus(stderr, "The number of imported RSA keys: %d\n",

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import_result->imported_rsa);

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fprintf_plus(stderr, "The number of unchanged keys: %d\n",

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import_result->unchanged);

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fprintf_plus(stderr, "The number of new user IDs: %d\n",

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import_result->new_user_ids);

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fprintf_plus(stderr, "The number of new sub keys: %d\n",

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import_result->new_sub_keys);

337

fprintf_plus(stderr, "The number of new signatures: %d\n",

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import_result->new_signatures);

339

fprintf_plus(stderr, "The number of new revocations: %d\n",

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import_result->new_revocations);

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fprintf_plus(stderr,

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"The total number of secret keys read: %d\n",

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import_result->secret_read);

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fprintf_plus(stderr,

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"The number of imported secret keys: %d\n",

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import_result->secret_imported);

347

fprintf_plus(stderr,

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"The number of unchanged secret keys: %d\n",

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import_result->secret_unchanged);

350

fprintf_plus(stderr, "The number of keys not imported: %d\n",

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import_result->not_imported);

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for(gpgme_import_status_t import_status

353

= import_result->imports;

354

import_status != NULL;

355

import_status = import_status->next){

356

fprintf_plus(stderr, "Import status for key: %s\n",

357

import_status->fpr);

358

if(import_status->result != GPG_ERR_NO_ERROR){

359

fprintf_plus(stderr, "Import result: %s: %s\n",

360

gpgme_strsource(import_status->result),

361

gpgme_strerror(import_status->result));

362

}

363

fprintf_plus(stderr, "Key status:\n");

364

fprintf_plus(stderr,

365

import_status->status & GPGME_IMPORT_NEW

366

? "The key was new.\n"

367

: "The key was not new.\n");

368

fprintf_plus(stderr,

369

import_status->status & GPGME_IMPORT_UID

370

? "The key contained new user IDs.\n"

371

: "The key did not contain new user IDs.\n");

372

fprintf_plus(stderr,

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import_status->status & GPGME_IMPORT_SIG

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? "The key contained new signatures.\n"

375

: "The key did not contain new signatures.\n");

376

fprintf_plus(stderr,

377

import_status->status & GPGME_IMPORT_SUBKEY

378

? "The key contained new sub keys.\n"

379

: "The key did not contain new sub keys.\n");

380

fprintf_plus(stderr,

381

import_status->status & GPGME_IMPORT_SECRET

382

? "The key contained a secret key.\n"

383

: "The key did not contain a secret key.\n");

384

}

385

return false;

386

}

387

}

388

280

389

ret = close(fd);

281

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

390

282

if(ret == -1){

391

283

perror_plus("close");

392

284

}

429

321

}

430

322

431

323

/* Create new GPGME "context" */

432

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

324

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

433

325

if(rc != GPG_ERR_NO_ERROR){

434

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

435

gpgme_strsource(rc), gpgme_strerror(rc));

326

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

327

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

328

gpgme_strerror(rc));

436

329

return false;

437

330

}

438

331

447

340

* Decrypt OpenPGP data.

448

341

* Returns -1 on error

449

342

*/

450

__attribute__((nonnull, warn_unused_result))

451

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

452

344

size_t crypto_size,

453

char **plaintext,

454

mandos_context *mc){

345

char **plaintext){

455

346

gpgme_data_t dh_crypto, dh_plain;

456

347

gpgme_error_t rc;

457

348

ssize_t ret;

474

365

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

475

366

rc = gpgme_data_new(&dh_plain);

476

367

if(rc != GPG_ERR_NO_ERROR){

477

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

368

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

369

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

478

370

gpgme_strsource(rc), gpgme_strerror(rc));

479

371

gpgme_data_release(dh_crypto);

480

372

return -1;

482

374

483

375

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

484

376

data buffer */

485

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

377

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

486

378

if(rc != GPG_ERR_NO_ERROR){

487

379

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

488

380

gpgme_strsource(rc), gpgme_strerror(rc));

489

381

plaintext_length = -1;

490

382

if(debug){

491

383

gpgme_decrypt_result_t result;

492

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

493

385

if(result == NULL){

494

386

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

495

387

} else {

496

if(result->unsupported_algorithm != NULL) {

497

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

498

result->unsupported_algorithm);

499

}

500

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

501

result->wrong_key_usage ? "Yes" : "No");

388

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

389

result->unsupported_algorithm);

390

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

391

result->wrong_key_usage);

502

392

if(result->file_name != NULL){

503

393

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

504

394

}

505

506

for(gpgme_recipient_t r = result->recipients; r != NULL;

507

r = r->next){

395

gpgme_recipient_t recipient;

396

recipient = result->recipients;

397

while(recipient != NULL){

508

398

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

509

gpgme_pubkey_algo_name(r->pubkey_algo));

510

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

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

511

402

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

512

r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

405

recipient = recipient->next;

513

406

}

514

407

}

515

408

}

571

464

return plaintext_length;

572

465

}

573

466

574

__attribute__((warn_unused_result, const))

575

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

576

if(str == NULL)

577

return "(unknown)";

578

return str;

579

}

580

581

__attribute__((warn_unused_result))

582

static const char *safer_gnutls_strerror(int value){

583

const char *ret = gnutls_strerror(value);

584

return safe_string(ret);

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

470

if(ret == NULL)

471

ret = "(unknown)";

472

return ret;

585

473

}

586

474

587

475

/* GnuTLS log function callback */

588

__attribute__((nonnull))

589

476

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

590

477

const char* string){

591

478

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

592

479

}

593

480

594

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

595

481

static int init_gnutls_global(const char *pubkeyfilename,

596

const char *seckeyfilename,

597

const char *dhparamsfilename,

598

mandos_context *mc){

482

const char *seckeyfilename){

599

483

int ret;

600

unsigned int uret;

601

484

602

485

if(debug){

603

486

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

604

487

}

605

488

489

ret = gnutls_global_init();

490

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

493

return -1;

494

}

495

606

496

if(debug){

607

497

/* "Use a log level over 10 to enable all debugging options."

608

498

* - GnuTLS manual

612

502

}

613

503

614

504

/* OpenPGP credentials */

615

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

616

506

if(ret != GNUTLS_E_SUCCESS){

617

507

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

618

508

safer_gnutls_strerror(ret));

509

gnutls_global_deinit();

619

510

return -1;

620

511

}

621

512

627

518

}

628

519

629

520

ret = gnutls_certificate_set_openpgp_key_file

630

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

631

522

GNUTLS_OPENPGP_FMT_BASE64);

632

523

if(ret != GNUTLS_E_SUCCESS){

633

524

fprintf_plus(stderr,

639

530

}

640

531

641

532

/* GnuTLS server initialization */

642

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

643

534

if(ret != GNUTLS_E_SUCCESS){

644

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

645

536

" initialization: %s\n",

646

537

safer_gnutls_strerror(ret));

647

538

goto globalfail;

648

539

}

649

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

650

if(dhparamsfilename != NULL){

651

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

652

do {

653

int dhpfile = open(dhparamsfilename, O_RDONLY);

654

if(dhpfile == -1){

655

perror_plus("open");

656

dhparamsfilename = NULL;

657

break;

658

}

659

size_t params_capacity = 0;

660

while(true){

661

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

662

(size_t)params.size,

663

(size_t)params_capacity);

664

if(params_capacity == 0){

665

perror_plus("incbuffer");

666

free(params.data);

667

params.data = NULL;

668

dhparamsfilename = NULL;

669

break;

670

}

671

ssize_t bytes_read = read(dhpfile,

672

params.data + params.size,

673

BUFFER_SIZE);

674

/* EOF */

675

if(bytes_read == 0){

676

break;

677

}

678

/* check bytes_read for failure */

679

if(bytes_read < 0){

680

perror_plus("read");

681

free(params.data);

682

params.data = NULL;

683

dhparamsfilename = NULL;

684

break;

685

}

686

params.size += (unsigned int)bytes_read;

687

}

688

ret = close(dhpfile);

689

if(ret == -1){

690

perror_plus("close");

691

}

692

if(params.data == NULL){

693

dhparamsfilename = NULL;

694

}

695

if(dhparamsfilename == NULL){

696

break;

697

}

698

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

699

GNUTLS_X509_FMT_PEM);

700

if(ret != GNUTLS_E_SUCCESS){

701

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

702

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

703

safer_gnutls_strerror(ret));

704

dhparamsfilename = NULL;

705

}

706

free(params.data);

707

} while(false);

708

}

709

if(dhparamsfilename == NULL){

710

if(mc->dh_bits == 0){

711

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

712

/* Try to read the private key file */

713

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

714

do {

715

int secfile = open(seckeyfilename, O_RDONLY);

716

if(secfile == -1){

717

perror_plus("open");

718

break;

719

}

720

size_t buffer_capacity = 0;

721

while(true){

722

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

723

(size_t)buffer.size,

724

(size_t)buffer_capacity);

725

if(buffer_capacity == 0){

726

perror_plus("incbuffer");

727

free(buffer.data);

728

buffer.data = NULL;

729

break;

730

}

731

ssize_t bytes_read = read(secfile,

732

buffer.data + buffer.size,

733

BUFFER_SIZE);

734

/* EOF */

735

if(bytes_read == 0){

736

break;

737

}

738

/* check bytes_read for failure */

739

if(bytes_read < 0){

740

perror_plus("read");

741

free(buffer.data);

742

buffer.data = NULL;

743

break;

744

}

745

buffer.size += (unsigned int)bytes_read;

746

}

747

close(secfile);

748

} while(false);

749

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

750

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

751

if(buffer.data != NULL){

752

{

753

gnutls_openpgp_privkey_t privkey = NULL;

754

ret = gnutls_openpgp_privkey_init(&privkey);

755

if(ret != GNUTLS_E_SUCCESS){

756

fprintf_plus(stderr, "Error initializing OpenPGP key"

757

" structure: %s",

758

safer_gnutls_strerror(ret));

759

free(buffer.data);

760

buffer.data = NULL;

761

} else {

762

ret = gnutls_openpgp_privkey_import

763

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

764

if(ret != GNUTLS_E_SUCCESS){

765

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

766

safer_gnutls_strerror(ret));

767

privkey = NULL;

768

}

769

free(buffer.data);

770

buffer.data = NULL;

771

if(privkey != NULL){

772

/* Use private key to suggest an appropriate

773

sec_param */

774

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

775

gnutls_openpgp_privkey_deinit(privkey);

776

if(debug){

777

fprintf_plus(stderr, "This OpenPGP key implies using"

778

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

779

safe_string(gnutls_sec_param_get_name

780

(sec_param)));

781

}

782

}

783

}

784

}

785

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

786

/* Err on the side of caution */

787

sec_param = GNUTLS_SEC_PARAM_ULTRA;

788

if(debug){

789

fprintf_plus(stderr, "Falling back to security parameter"

790

" \"%s\"\n",

791

safe_string(gnutls_sec_param_get_name

792

(sec_param)));

793

}

794

}

795

}

796

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

797

if(uret != 0){

798

mc->dh_bits = uret;

799

if(debug){

800

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

801

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

802

safe_string(gnutls_sec_param_get_name

803

(sec_param)),

804

mc->dh_bits);

805

}

806

} else {

807

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

808

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

809

safe_string(gnutls_sec_param_get_name

810

(sec_param)),

811

safer_gnutls_strerror(ret));

812

goto globalfail;

813

}

814

} else if(debug){

815

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

816

mc->dh_bits);

817

}

818

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

819

if(ret != GNUTLS_E_SUCCESS){

820

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

821

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

822

safer_gnutls_strerror(ret));

823

goto globalfail;

824

}

825

}

826

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

540

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

541

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

544

goto globalfail;

545

}

546

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

827

548

828

549

return 0;

829

550

830

551

globalfail:

831

552

832

gnutls_certificate_free_credentials(mc->cred);

833

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_certificate_free_credentials(mc.cred);

554

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

834

556

return -1;

835

557

}

836

558

837

__attribute__((nonnull, warn_unused_result))

838

static int init_gnutls_session(gnutls_session_t *session,

839

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

840

560

int ret;

841

561

/* GnuTLS session creation */

842

562

do {

854

574

{

855

575

const char *err;

856

576

do {

857

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

577

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

858

578

if(quit_now){

859

579

gnutls_deinit(*session);

860

580

return -1;

871

591

872

592

do {

873

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

874

mc->cred);

594

mc.cred);

875

595

if(quit_now){

876

596

gnutls_deinit(*session);

877

597

return -1;

887

607

/* ignore client certificate if any. */

888

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

889

609

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

611

890

612

return 0;

891

613

}

892

614

894

616

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

895

617

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

896

618

897

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

898

__attribute__((warn_unused_result))

899

int raise_privileges(void){

900

int old_errno = errno;

901

int ret = 0;

902

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

903

ret = errno;

904

}

905

errno = old_errno;

906

return ret;

907

}

908

909

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

910

__attribute__((warn_unused_result))

911

int raise_privileges_permanently(void){

912

int old_errno = errno;

913

int ret = raise_privileges();

914

if(ret != 0){

915

errno = old_errno;

916

return ret;

917

}

918

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

919

ret = errno;

920

}

921

errno = old_errno;

922

return ret;

923

}

924

925

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

926

__attribute__((warn_unused_result))

927

int lower_privileges(void){

928

int old_errno = errno;

929

int ret = 0;

930

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

931

ret = errno;

932

}

933

errno = old_errno;

934

return ret;

935

}

936

937

/* Lower privileges permanently */

938

__attribute__((warn_unused_result))

939

int lower_privileges_permanently(void){

940

int old_errno = errno;

941

int ret = 0;

942

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

943

ret = errno;

944

}

945

errno = old_errno;

946

return ret;

947

}

948

949

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

950

__attribute__((nonnull, warn_unused_result))

951

static bool add_delete_local_route(const bool add,

952

const char *address,

953

AvahiIfIndex if_index){

954

int ret;

955

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

956

char add_arg[] = "add";

957

char delete_arg[] = "delete";

958

char debug_flag[] = "--debug";

959

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

960

if(pluginhelperdir == NULL){

961

if(debug){

962

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

963

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

964

}

965

return false;

966

}

967

968

char interface[IF_NAMESIZE];

969

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

970

perror_plus("if_indextoname");

971

return false;

972

}

973

974

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

975

if(devnull == -1){

976

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

977

return false;

978

}

979

pid_t pid = fork();

980

if(pid == 0){

981

/* Child */

982

/* Raise privileges */

983

errno = raise_privileges_permanently();

984

if(errno != 0){

985

perror_plus("Failed to raise privileges");

986

/* _exit(EX_NOPERM); */

987

} else {

988

/* Set group */

989

errno = 0;

990

ret = setgid(0);

991

if(ret == -1){

992

perror_plus("setgid");

993

_exit(EX_NOPERM);

994

}

995

/* Reset supplementary groups */

996

errno = 0;

997

ret = setgroups(0, NULL);

998

if(ret == -1){

999

perror_plus("setgroups");

1000

_exit(EX_NOPERM);

1001

}

1002

}

1003

ret = dup2(devnull, STDIN_FILENO);

1004

if(ret == -1){

1005

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

1006

_exit(EX_OSERR);

1007

}

1008

ret = close(devnull);

1009

if(ret == -1){

1010

perror_plus("close");

1011

_exit(EX_OSERR);

1012

}

1013

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1014

if(ret == -1){

1015

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

1016

_exit(EX_OSERR);

1017

}

1018

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

1019

O_RDONLY

1020

| O_DIRECTORY

1021

| O_PATH

1022

| O_CLOEXEC));

1023

if(helperdir_fd == -1){

1024

perror_plus("open");

1025

_exit(EX_UNAVAILABLE);

1026

}

1027

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

1028

helper, O_RDONLY));

1029

if(helper_fd == -1){

1030

perror_plus("openat");

1031

close(helperdir_fd);

1032

_exit(EX_UNAVAILABLE);

1033

}

1034

close(helperdir_fd);

1035

#ifdef __GNUC__

1036

#pragma GCC diagnostic push

1037

#pragma GCC diagnostic ignored "-Wcast-qual"

1038

#endif

1039

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

1040

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

1041

interface, debug ? debug_flag : NULL, NULL },

1042

environ) == -1){

1043

#ifdef __GNUC__

1044

#pragma GCC diagnostic pop

1045

#endif

1046

perror_plus("fexecve");

1047

_exit(EXIT_FAILURE);

1048

}

1049

}

1050

if(pid == -1){

1051

perror_plus("fork");

1052

return false;

1053

}

1054

int status;

1055

pid_t pret = -1;

1056

errno = 0;

1057

do {

1058

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

1059

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

1060

int errno_raising = 0;

1061

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

1062

errno_raising = errno;

1063

perror_plus("Failed to raise privileges in order to"

1064

" kill helper program");

1065

}

1066

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

1067

perror_plus("kill");

1068

}

1069

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

1070

perror_plus("Failed to lower privileges after killing"

1071

" helper program");

1072

}

1073

return false;

1074

}

1075

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

1076

if(pret == -1){

1077

perror_plus("waitpid");

1078

return false;

1079

}

1080

if(WIFEXITED(status)){

1081

if(WEXITSTATUS(status) != 0){

1082

fprintf_plus(stderr, "Error: iprouteadddel exited"

1083

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

1084

return false;

1085

}

1086

return true;

1087

}

1088

if(WIFSIGNALED(status)){

1089

fprintf_plus(stderr, "Error: iprouteadddel died by"

1090

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

1091

return false;

1092

}

1093

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

1094

return false;

1095

}

1096

1097

__attribute__((nonnull, warn_unused_result))

1098

static bool add_local_route(const char *address,

1099

AvahiIfIndex if_index){

1100

if(debug){

1101

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

1102

}

1103

return add_delete_local_route(true, address, if_index);

1104

}

1105

1106

__attribute__((nonnull, warn_unused_result))

1107

static bool delete_local_route(const char *address,

1108

AvahiIfIndex if_index){

1109

if(debug){

1110

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

1111

}

1112

return add_delete_local_route(false, address, if_index);

1113

}

1114

1115

619

/* Called when a Mandos server is found */

1116

__attribute__((nonnull, warn_unused_result))

1117

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

620

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

1118

621

AvahiIfIndex if_index,

1119

int af, mandos_context *mc){

622

int af){

1120

623

int ret, tcp_sd = -1;

1121

624

ssize_t sret;

1122

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

1123

629

char *buffer = NULL;

1124

630

char *decrypted_buffer = NULL;

1125

631

size_t buffer_length = 0;

1128

634

int retval = -1;

1129

635

gnutls_session_t session;

1130

636

int pf; /* Protocol family */

1131

bool route_added = false;

1132

637

1133

638

errno = 0;

1134

639

1150

655

return -1;

1151

656

}

1152

657

1153

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

1154

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

1155

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

1156

bool match = false;

1157

{

1158

char *interface = NULL;

1159

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

1160

mc->interfaces_size,

1161

interface))){

1162

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

1163

match = true;

1164

break;

1165

}

1166

}

1167

}

1168

if(not match){

1169

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

1170

connect to the server */

1171

if(debug){

1172

char interface[IF_NAMESIZE];

1173

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

1174

perror_plus("if_indextoname");

1175

} else {

1176

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

1177

" \"%s\"\n",

1178

if_indextoname((unsigned int)if_index,

1179

interface));

1180

}

1181

}

1182

return -1;

1183

}

1184

}

1185

1186

ret = init_gnutls_session(&session, mc);

658

ret = init_gnutls_session(&session);

1187

659

if(ret != 0){

1188

660

return -1;

1189

661

}

1190

662

1191

663

if(debug){

1192

664

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

1193

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

665

PRIu16 "\n", ip, port);

1194

666

}

1195

667

1196

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

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

1197

669

if(tcp_sd < 0){

1198

670

int e = errno;

1199

671

perror_plus("socket");

1206

678

goto mandos_end;

1207

679

}

1208

680

681

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

1209

682

if(af == AF_INET6){

1210

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

1211

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

1212

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

683

to.in6.sin6_family = (sa_family_t)af;

684

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

1213

685

} else { /* IPv4 */

1214

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

1215

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

1216

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

686

to.in.sin_family = (sa_family_t)af;

687

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

1217

688

}

1218

689

if(ret < 0 ){

1219

690

int e = errno;

1228

699

goto mandos_end;

1229

700

}

1230

701

if(af == AF_INET6){

1231

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

1232

if(IN6_IS_ADDR_LINKLOCAL

1233

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

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

1234

709

if(if_index == AVAHI_IF_UNSPEC){

1235

710

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

1236

711

" incomplete without a network interface\n");

1238

713

goto mandos_end;

1239

714

}

1240

715

/* Set the network interface number as scope */

1241

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

1242

717

}

1243

718

} else {

1244

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

1245

722

}

1246

723

1247

724

if(quit_now){

1255

732

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

1256

733

perror_plus("if_indextoname");

1257

734

} else {

1258

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

1259

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

735

fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16

736

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

1260

737

}

1261

738

} else {

1262

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

1263

ip, (uintmax_t)port);

739

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

740

ip, port);

1264

741

}

1265

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1266

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1267

if(af == AF_INET6){

1268

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

1269

sizeof(struct sockaddr_in6),

1270

addrstr, sizeof(addrstr), NULL, 0,

1271

NI_NUMERICHOST);

1272

} else {

1273

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

1274

sizeof(struct sockaddr_in),

1275

addrstr, sizeof(addrstr), NULL, 0,

1276

NI_NUMERICHOST);

1277

}

1278

if(ret == EAI_SYSTEM){

1279

perror_plus("getnameinfo");

1280

} else if(ret != 0) {

1281

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

1282

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

1283

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

1284

}

1285

}

1286

1287

if(quit_now){

1288

errno = EINTR;

1289

goto mandos_end;

1290

}

1291

1292

while(true){

1293

if(af == AF_INET6){

1294

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

1295

sizeof(struct sockaddr_in6));

1296

} else {

1297

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

1298

sizeof(struct sockaddr_in));

1299

}

1300

if(ret < 0){

1301

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

1302

and if_index != AVAHI_IF_UNSPEC

1303

and connect_to == NULL

1304

and not route_added and

1305

((af == AF_INET6 and not

1306

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1307

&to)->sin6_addr)))

1308

or (af == AF_INET and

1309

/* Not a a IPv4LL address */

1310

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

1311

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

1312

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

1313

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

1314

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

1315

connect to a Mandos server announced by Avahi on a server

1316

host with a global address. Work around this by retrying

1317

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

1318

1319

Avahi bug reference:

1320

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

1321

https://bugs.debian.org/587961

1322

*/

1323

if(debug){

1324

fprintf_plus(stderr, "Mandos server unreachable, trying"

1325

" direct route\n");

1326

}

1327

int e = errno;

1328

route_added = add_local_route(ip, if_index);

1329

if(route_added){

1330

continue;

1331

}

1332

errno = e;

1333

}

1334

if(errno != ECONNREFUSED or debug){

1335

int e = errno;

1336

perror_plus("connect");

1337

errno = e;

1338

}

1339

goto mandos_end;

1340

}

1341

1342

if(quit_now){

1343

errno = EINTR;

1344

goto mandos_end;

1345

}

1346

break;

744

const char *pcret;

745

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

748

} else {

749

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

750

sizeof(addrstr));

751

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

758

}

759

}

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

if(af == AF_INET6){

767

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

768

} else {

769

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

770

}

771

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

1347

783

}

1348

784

1349

785

const char *out = mandos_protocol_version;

1385

821

goto mandos_end;

1386

822

}

1387

823

1388

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

1389

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

1390

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

1391

gnutls_transport_set_ptr(session,

1392

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1393

826

1394

827

if(quit_now){

1395

828

errno = EINTR;

1500

933

if(buffer_length > 0){

1501

934

ssize_t decrypted_buffer_size;

1502

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1503

&decrypted_buffer, mc);

936

&decrypted_buffer);

1504

937

if(decrypted_buffer_size >= 0){

1505

938

1506

clearerr(stdout);

1507

939

written = 0;

1508

940

while(written < (size_t) decrypted_buffer_size){

1509

941

if(quit_now){

1525

957

}

1526

958

written += (size_t)ret;

1527

959

}

1528

ret = fflush(stdout);

1529

if(ret != 0){

1530

int e = errno;

1531

if(debug){

1532

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

1533

strerror(errno));

1534

}

1535

errno = e;

1536

goto mandos_end;

1537

}

1538

960

retval = 0;

1539

961

}

1540

962

}

1543

965

1544

966

mandos_end:

1545

967

{

1546

if(route_added){

1547

if(not delete_local_route(ip, if_index)){

1548

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

1549

" interface %d", ip, if_index);

1550

}

1551

}

1552

968

int e = errno;

1553

969

free(decrypted_buffer);

1554

970

free(buffer);

1555

971

if(tcp_sd >= 0){

1556

ret = close(tcp_sd);

972

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

1557

973

}

1558

974

if(ret == -1){

1559

975

if(e == 0){

1584

1000

AVAHI_GCC_UNUSED AvahiStringList *txt,

1585

1001

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1586

1002

flags,

1587

void *mc){

1588

if(r == NULL){

1589

return;

1590

}

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1591

1005

1592

1006

/* Called whenever a service has been resolved successfully or

1593

1007

timed out */

1594

1008

1595

1009

if(quit_now){

1596

avahi_s_service_resolver_free(r);

1597

1010

return;

1598

1011

}

1599

1012

1603

1016

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

1604

1017

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

1605

1018

domain,

1606

avahi_strerror(avahi_server_errno

1607

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

1019

avahi_strerror(avahi_server_errno(mc.server)));

1608

1020

break;

1609

1021

1610

1022

case AVAHI_RESOLVER_FOUND:

1616

1028

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

1617

1029

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

1618

1030

}

1619

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

1620

interface,

1621

avahi_proto_to_af(proto),

1622

mc);

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1623

1033

if(ret == 0){

1624

avahi_simple_poll_quit(simple_poll);

1034

avahi_simple_poll_quit(mc.simple_poll);

1625

1035

} else {

1626

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

1627

avahi_proto_to_af(proto),

1628

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

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1629

1038

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

1630

1039

" list\n", name);

1631

1040

}

1644

1053

const char *domain,

1645

1054

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1646

1055

flags,

1647

void *mc){

1648

if(b == NULL){

1649

return;

1650

}

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1651

1058

1652

1059

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

1653

1060

is removed from the LAN */

1661

1068

case AVAHI_BROWSER_FAILURE:

1662

1069

1663

1070

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

1664

avahi_strerror(avahi_server_errno

1665

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

1666

avahi_simple_poll_quit(simple_poll);

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1667

1073

return;

1668

1074

1669

1075

case AVAHI_BROWSER_NEW:

1672

1078

the callback function is called the Avahi server will free the

1673

1079

resolver for us. */

1674

1080

1675

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

1676

interface, protocol, name, type,

1677

domain, protocol, 0,

1678

resolve_callback, mc) == NULL)

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1679

1084

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

1680

1085

" %s\n", name,

1681

avahi_strerror(avahi_server_errno

1682

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

1086

avahi_strerror(avahi_server_errno(mc.server)));

1683

1087

break;

1684

1088

1685

1089

case AVAHI_BROWSER_REMOVE:

1704

1108

signal_received = sig;

1705

1109

int old_errno = errno;

1706

1110

/* set main loop to exit */

1707

if(simple_poll != NULL){

1708

avahi_simple_poll_quit(simple_poll);

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1709

1113

}

1710

1114

errno = old_errno;

1711

1115

}

1712

1116

1713

__attribute__((nonnull, warn_unused_result))

1714

1117

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

1715

1118

int ret;

1716

int old_errno;

1717

1119

1718

1120

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

1719

1121

if(s < 0){

1720

old_errno = errno;

1721

1122

perror_plus("socket");

1722

errno = old_errno;

1723

1123

return false;

1724

1124

}

1725

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

1726

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

1125

strcpy(ifr->ifr_name, ifname);

1727

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1728

1127

if(ret == -1){

1729

1128

if(debug){

1730

old_errno = errno;

1731

1129

perror_plus("ioctl SIOCGIFFLAGS");

1732

errno = old_errno;

1733

}

1734

if((close(s) == -1) and debug){

1735

old_errno = errno;

1736

perror_plus("close");

1737

errno = old_errno;

1738

1130

}

1739

1131

return false;

1740

1132

}

1741

if((close(s) == -1) and debug){

1742

old_errno = errno;

1743

perror_plus("close");

1744

errno = old_errno;

1745

}

1746

1133

return true;

1747

1134

}

1748

1135

1749

__attribute__((nonnull, warn_unused_result))

1750

1136

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

1751

1137

1752

1138

/* Reject the loopback device */

1794

1180

* corresponds to an acceptable network device.

1795

1181

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

1796

1182

*/

1797

__attribute__((nonnull, warn_unused_result))

1798

1183

int good_interface(const struct dirent *if_entry){

1799

1184

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

1800

1185

return 0;

1816

1201

}

1817

1202

1818

1203

/*

1819

* This function determines if a network interface is up.

1820

*/

1821

__attribute__((nonnull, warn_unused_result))

1822

bool interface_is_up(const char *interface){

1823

struct ifreq ifr;

1824

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

1825

if(debug){

1826

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

1827

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

1828

}

1829

return false;

1830

}

1831

1832

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

1833

}

1834

1835

/*

1836

* This function determines if a network interface is running

1837

*/

1838

__attribute__((nonnull, warn_unused_result))

1839

bool interface_is_running(const char *interface){

1840

struct ifreq ifr;

1841

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

1842

if(debug){

1843

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

1844

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

1845

}

1846

return false;

1847

}

1848

1849

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

1850

}

1851

1852

__attribute__((nonnull, pure, warn_unused_result))

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

if(not (ifr.ifr_flags & IFF_UP)){

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

if(not (ifr.ifr_flags & IFF_RUNNING)){

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1853

1246

int notdotentries(const struct dirent *direntry){

1854

1247

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

1855

1248

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

1862

1255

}

1863

1256

1864

1257

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

1865

__attribute__((nonnull, warn_unused_result))

1866

1258

int runnable_hook(const struct dirent *direntry){

1867

1259

int ret;

1868

1260

size_t sret;

1876

1268

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

1877

1269

"abcdefghijklmnopqrstuvwxyz"

1878

1270

"0123456789"

1879

"_.-");

1271

"_-");

1880

1272

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

1881

1273

/* Contains non-allowed characters */

1882

1274

if(debug){

1886

1278

return 0;

1887

1279

}

1888

1280

1889

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

1281

char *fullname = NULL;

1282

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1283

if(ret < 0){

1284

perror_plus("asprintf");

1285

return 0;

1286

}

1287

1288

ret = stat(fullname, &st);

1890

1289

if(ret == -1){

1891

1290

if(debug){

1892

1291

perror_plus("Could not stat hook");

1916

1315

return 1;

1917

1316

}

1918

1317

1919

__attribute__((nonnull, warn_unused_result))

1920

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1921

mandos_context *mc){

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1922

1319

int ret;

1923

1320

struct timespec now;

1924

1321

struct timespec waited_time;

1925

1322

intmax_t block_time;

1926

1323

1927

1324

while(true){

1928

if(mc->current_server == NULL){

1929

if(debug){

1325

if(mc.current_server == NULL){

1326

if (debug){

1930

1327

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

1931

1328

" No timeout!\n");

1932

1329

}

1933

1330

ret = avahi_simple_poll_iterate(s, -1);

1934

1331

} else {

1935

if(debug){

1332

if (debug){

1936

1333

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

1937

1334

" it, or wait\n");

1938

1335

}

1945

1342

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

1946

1343

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

1947

1344

waited_time.tv_sec = (now.tv_sec

1948

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

1345

- mc.current_server->last_seen.tv_sec);

1949

1346

waited_time.tv_nsec = (now.tv_nsec

1950

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

1347

- mc.current_server->last_seen.tv_nsec);

1951

1348

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

1952

1349

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

1953

1350

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

1955

1352

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

1956

1353

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

1957

1354

1958

if(debug){

1355

if (debug){

1959

1356

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

1960

1357

block_time);

1961

1358

}

1962

1359

1963

1360

if(block_time <= 0){

1964

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

1965

mc->current_server->port,

1966

mc->current_server->if_index,

1967

mc->current_server->af, mc);

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

1968

1365

if(ret == 0){

1969

avahi_simple_poll_quit(s);

1366

avahi_simple_poll_quit(mc.simple_poll);

1970

1367

return 0;

1971

1368

}

1972

1369

ret = clock_gettime(CLOCK_MONOTONIC,

1973

&mc->current_server->last_seen);

1370

&mc.current_server->last_seen);

1974

1371

if(ret == -1){

1975

1372

perror_plus("clock_gettime");

1976

1373

return -1;

1977

1374

}

1978

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

1375

mc.current_server = mc.current_server->next;

1979

1376

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

1980

1377

servers, but don't block */

1981

1378

}

1983

1380

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

1984

1381

}

1985

1382

if(ret != 0){

1986

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

1383

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

1987

1384

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

1988

1385

}

1989

1386

}

1990

1387

}

1991

1388

}

1992

1389

1993

__attribute__((nonnull))

1994

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

1390

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

1995

1391

const float delay){

1996

struct dirent **direntries = NULL;

1997

if(hookdir_fd == -1){

1998

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

1999

| O_CLOEXEC);

2000

if(hookdir_fd == -1){

2001

if(errno == ENOENT){

2002

if(debug){

2003

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

2004

" found\n", hookdir);

2005

}

2006

} else {

2007

perror_plus("open");

2008

}

2009

return;

2010

}

2011

}

2012

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

2013

if(devnull == -1){

2014

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

2015

return;

2016

}

2017

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

2018

runnable_hook, alphasort);

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

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

1396

alphasort);

2019

1397

if(numhooks == -1){

2020

1398

perror_plus("scandir");

2021

close(devnull);

2022

return;

2023

}

2024

struct dirent *direntry;

2025

int ret;

2026

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

2027

direntry = direntries[i];

2028

if(debug){

2029

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

2030

direntry->d_name);

2031

}

2032

pid_t hook_pid = fork();

2033

if(hook_pid == 0){

2034

/* Child */

2035

/* Raise privileges */

2036

errno = raise_privileges_permanently();

2037

if(errno != 0){

2038

perror_plus("Failed to raise privileges");

2039

_exit(EX_NOPERM);

2040

}

2041

/* Set group */

2042

errno = 0;

2043

ret = setgid(0);

2044

if(ret == -1){

2045

perror_plus("setgid");

2046

_exit(EX_NOPERM);

2047

}

2048

/* Reset supplementary groups */

2049

errno = 0;

2050

ret = setgroups(0, NULL);

2051

if(ret == -1){

2052

perror_plus("setgroups");

2053

_exit(EX_NOPERM);

2054

}

2055

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

2056

if(ret == -1){

2057

perror_plus("setenv");

2058

_exit(EX_OSERR);

2059

}

2060

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

2061

if(ret == -1){

2062

perror_plus("setenv");

2063

_exit(EX_OSERR);

2064

}

2065

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

2066

if(ret == -1){

2067

perror_plus("setenv");

2068

_exit(EX_OSERR);

2069

}

2070

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

2071

if(ret == -1){

2072

perror_plus("setenv");

2073

_exit(EX_OSERR);

2074

}

2075

char *delaystring;

2076

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

2077

if(ret == -1){

1399

} else {

1400

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

1401

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

1402

direntry = direntries[i];

1403

char *fullname = NULL;

1404

ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);

1405

if(ret < 0){

2078

1406

perror_plus("asprintf");

2079

_exit(EX_OSERR);

2080

}

2081

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

2082

if(ret == -1){

1407

continue;

1408

}

1409

if(debug){

1410

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

1411

direntry->d_name);

1412

}

1413

pid_t hook_pid = fork();

1414

if(hook_pid == 0){

1415

/* Child */

1416

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1428

/* Set group */

1429

errno = 0;

1430

ret = setgid(0);

1431

if(ret == -1){

1432

perror_plus("setgid");

1433

}

1434

/* Reset supplementary groups */

1435

errno = 0;

1436

ret = setgroups(0, NULL);

1437

if(ret == -1){

1438

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1443

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

1444

if(ret == -1){

1445

perror_plus("setenv");

1446

_exit(EX_OSERR);

1447

}

1448

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

1449

if(ret == -1){

1450

perror_plus("setenv");

1451

_exit(EX_OSERR);

1452

}

1453

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

1454

if(ret == -1){

1455

perror_plus("setenv");

1456

_exit(EX_OSERR);

1457

}

1458

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

1459

if(ret == -1){

1460

perror_plus("setenv");

1461

_exit(EX_OSERR);

1462

}

1463

char *delaystring;

1464

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

1465

if(ret == -1){

1466

perror_plus("asprintf");

1467

_exit(EX_OSERR);

1468

}

1469

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

1470

if(ret == -1){

1471

free(delaystring);

1472

perror_plus("setenv");

1473

_exit(EX_OSERR);

1474

}

2083

1475

free(delaystring);

2084

perror_plus("setenv");

2085

_exit(EX_OSERR);

2086

}

2087

free(delaystring);

2088

if(connect_to != NULL){

2089

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

2090

if(ret == -1){

2091

perror_plus("setenv");

2092

_exit(EX_OSERR);

2093

}

2094

}

2095

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

2096

direntry->d_name,

2097

O_RDONLY));

2098

if(hook_fd == -1){

2099

perror_plus("openat");

2100

_exit(EXIT_FAILURE);

2101

}

2102

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

2103

perror_plus("close");

2104

_exit(EXIT_FAILURE);

2105

}

2106

ret = dup2(devnull, STDIN_FILENO);

2107

if(ret == -1){

2108

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

2109

_exit(EX_OSERR);

2110

}

2111

ret = close(devnull);

2112

if(ret == -1){

2113

perror_plus("close");

2114

_exit(EX_OSERR);

2115

}

2116

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2117

if(ret == -1){

2118

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

2119

_exit(EX_OSERR);

2120

}

2121

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

2122

environ) == -1){

2123

perror_plus("fexecve");

2124

_exit(EXIT_FAILURE);

2125

}

2126

} else {

2127

if(hook_pid == -1){

2128

perror_plus("fork");

2129

free(direntry);

2130

continue;

2131

}

2132

int status;

2133

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

2134

perror_plus("waitpid");

2135

free(direntry);

2136

continue;

2137

}

2138

if(WIFEXITED(status)){

2139

if(WEXITSTATUS(status) != 0){

2140

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

2141

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

2142

WEXITSTATUS(status));

2143

free(direntry);

2144

continue;

2145

}

2146

} else if(WIFSIGNALED(status)){

2147

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

2148

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

2149

WTERMSIG(status));

2150

free(direntry);

2151

continue;

2152

} else {

2153

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

2154

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

2155

free(direntry);

2156

continue;

2157

}

2158

}

2159

if(debug){

2160

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

2161

direntry->d_name);

2162

}

2163

free(direntry);

2164

}

2165

free(direntries);

2166

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

2167

perror_plus("close");

2168

} else {

2169

hookdir_fd = -1;

2170

}

2171

close(devnull);

2172

}

2173

2174

__attribute__((nonnull, warn_unused_result))

2175

int bring_up_interface(const char *const interface,

2176

const float delay){

2177

int old_errno = errno;

2178

int ret;

2179

struct ifreq network;

2180

unsigned int if_index = if_nametoindex(interface);

2181

if(if_index == 0){

2182

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

2183

errno = old_errno;

2184

return ENXIO;

2185

}

2186

2187

if(quit_now){

2188

errno = old_errno;

2189

return EINTR;

2190

}

2191

2192

if(not interface_is_up(interface)){

2193

int ret_errno = 0;

2194

int ioctl_errno = 0;

2195

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

2196

ret_errno = errno;

2197

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

2198

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

2199

errno = old_errno;

2200

return ret_errno;

2201

}

2202

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

2203

2204

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

2205

if(sd == -1){

2206

ret_errno = errno;

2207

perror_plus("socket");

2208

errno = old_errno;

2209

return ret_errno;

2210

}

2211

2212

if(quit_now){

2213

ret = close(sd);

2214

if(ret == -1){

2215

perror_plus("close");

2216

}

2217

errno = old_errno;

2218

return EINTR;

2219

}

2220

2221

if(debug){

2222

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

2223

interface);

2224

}

2225

2226

/* Raise privileges */

2227

ret_errno = raise_privileges();

2228

if(ret_errno != 0){

2229

errno = ret_errno;

2230

perror_plus("Failed to raise privileges");

2231

}

2232

2233

#ifdef __linux__

2234

int ret_linux;

2235

bool restore_loglevel = false;

2236

if(ret_errno == 0){

2237

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2238

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

2239

ret_linux = klogctl(8, NULL, 5);

2240

if(ret_linux == -1){

2241

perror_plus("klogctl");

2242

} else {

2243

restore_loglevel = true;

2244

}

2245

}

2246

#endif /* __linux__ */

2247

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

2248

ioctl_errno = errno;

2249

#ifdef __linux__

2250

if(restore_loglevel){

2251

ret_linux = klogctl(7, NULL, 0);

2252

if(ret_linux == -1){

2253

perror_plus("klogctl");

2254

}

2255

}

2256

#endif /* __linux__ */

2257

2258

/* If raise_privileges() succeeded above */

2259

if(ret_errno == 0){

2260

/* Lower privileges */

2261

ret_errno = lower_privileges();

2262

if(ret_errno != 0){

2263

errno = ret_errno;

2264

perror_plus("Failed to lower privileges");

2265

}

2266

}

2267

2268

/* Close the socket */

2269

ret = close(sd);

2270

if(ret == -1){

2271

perror_plus("close");

2272

}

2273

2274

if(ret_setflags == -1){

2275

errno = ioctl_errno;

2276

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2277

errno = old_errno;

2278

return ioctl_errno;

2279

}

2280

} else if(debug){

2281

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

2282

interface);

2283

}

2284

2285

/* Sleep checking until interface is running.

2286

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

2287

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

2288

if(interface_is_running(interface)){

2289

break;

2290

}

2291

struct timespec sleeptime = { .tv_nsec = 250000000 };

2292

ret = nanosleep(&sleeptime, NULL);

2293

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

2294

perror_plus("nanosleep");

2295

}

2296

}

2297

2298

errno = old_errno;

2299

return 0;

2300

}

2301

2302

__attribute__((nonnull, warn_unused_result))

2303

int take_down_interface(const char *const interface){

2304

int old_errno = errno;

2305

struct ifreq network;

2306

unsigned int if_index = if_nametoindex(interface);

2307

if(if_index == 0){

2308

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

2309

errno = old_errno;

2310

return ENXIO;

2311

}

2312

if(interface_is_up(interface)){

2313

int ret_errno = 0;

2314

int ioctl_errno = 0;

2315

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

2316

ret_errno = errno;

2317

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

2318

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

2319

errno = old_errno;

2320

return ret_errno;

2321

}

2322

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

2323

2324

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

2325

if(sd == -1){

2326

ret_errno = errno;

2327

perror_plus("socket");

2328

errno = old_errno;

2329

return ret_errno;

2330

}

2331

2332

if(debug){

2333

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

2334

interface);

2335

}

2336

2337

/* Raise privileges */

2338

ret_errno = raise_privileges();

2339

if(ret_errno != 0){

2340

errno = ret_errno;

2341

perror_plus("Failed to raise privileges");

2342

}

2343

2344

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

2345

ioctl_errno = errno;

2346

2347

/* If raise_privileges() succeeded above */

2348

if(ret_errno == 0){

2349

/* Lower privileges */

2350

ret_errno = lower_privileges();

2351

if(ret_errno != 0){

2352

errno = ret_errno;

2353

perror_plus("Failed to lower privileges");

2354

}

2355

}

2356

2357

/* Close the socket */

2358

int ret = close(sd);

2359

if(ret == -1){

2360

perror_plus("close");

2361

}

2362

2363

if(ret_setflags == -1){

2364

errno = ioctl_errno;

2365

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2366

errno = old_errno;

2367

return ioctl_errno;

2368

}

2369

} else if(debug){

2370

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

2371

interface);

2372

}

2373

2374

errno = old_errno;

2375

return 0;

1476

if(connect_to != NULL){

1477

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

1478

if(ret == -1){

1479

perror_plus("setenv");

1480

_exit(EX_OSERR);

1481

}

1482

}

1483

if(execl(fullname, direntry->d_name, mode, NULL) == -1){

1484

perror_plus("execl");

1485

_exit(EXIT_FAILURE);

1486

}

1487

} else {

1488

int status;

1489

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

1490

perror_plus("waitpid");

1491

free(fullname);

1492

continue;

1493

}

1494

if(WIFEXITED(status)){

1495

if(WEXITSTATUS(status) != 0){

1496

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

1497

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

1498

WEXITSTATUS(status));

1499

free(fullname);

1500

continue;

1501

}

1502

} else if(WIFSIGNALED(status)){

1503

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

1504

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

1505

WTERMSIG(status));

1506

free(fullname);

1507

continue;

1508

} else {

1509

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

1510

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

1511

free(fullname);

1512

continue;

1513

}

1514

}

1515

free(fullname);

1516

if(debug){

1517

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

1518

direntry->d_name);

1519

}

1520

}

1521

close(devnull);

1522

}

1523

return true;

2376

1524

}

2377

1525

2378

1526

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

2379

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

2380

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

2381

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

2382

.current_server = NULL, .interfaces = NULL,

2383

.interfaces_size = 0 };

2384

1527

AvahiSServiceBrowser *sb = NULL;

2385

error_t ret_errno;

1528

int error;

2386

1529

int ret;

2387

1530

intmax_t tmpmax;

2388

1531

char *tmp;

2389

1532

int exitcode = EXIT_SUCCESS;

2390

char *interfaces_to_take_down = NULL;

2391

size_t interfaces_to_take_down_size = 0;

2392

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

2393

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

2394

char *tempdir = NULL;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1539

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

1540

bool tempdir_created = false;

2395

1541

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2396

1542

const char *seckey = PATHDIR "/" SECKEY;

2397

1543

const char *pubkey = PATHDIR "/" PUBKEY;

2398

const char *dh_params_file = NULL;

2399

char *interfaces_hooks = NULL;

2400

1544

2401

1545

bool gnutls_initialized = false;

2402

1546

bool gpgme_initialized = false;

2454

1598

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

2455

1599

" Diffie-Hellman key exchange",

2456

1600

.group = 2 },

2457

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

2458

.arg = "FILE",

2459

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

2460

" for the Diffie-Hellman key exchange",

2461

.group = 2 },

2462

1601

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

2463

1602

.arg = "STRING",

2464

1603

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

2498

1637

connect_to = arg;

2499

1638

break;

2500

1639

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

2501

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

2502

arg, (int)',');

2503

if(ret_errno != 0){

2504

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

2505

}

1640

interface = arg;

2506

1641

break;

2507

1642

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

2508

1643

seckey = arg;

2519

1654

}

2520

1655

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

2521

1656

break;

2522

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

2523

dh_params_file = arg;

2524

break;

2525

1657

case 130: /* --priority */

2526

1658

mc.priority = arg;

2527

1659

break;

2567

1699

.args_doc = "",

2568

1700

.doc = "Mandos client -- Get and decrypt"

2569

1701

" passwords from a Mandos server" };

2570

ret_errno = argp_parse(&argp, argc, argv,

2571

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2572

switch(ret_errno){

1702

ret = argp_parse(&argp, argc, argv,

1703

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1704

switch(ret){

2573

1705

case 0:

2574

1706

break;

2575

1707

case ENOMEM:

2576

1708

default:

2577

errno = ret_errno;

1709

errno = ret;

2578

1710

perror_plus("argp_parse");

2579

1711

exitcode = EX_OSERR;

2580

1712

goto end;

2583

1715

goto end;

2584

1716

}

2585

1717

}

2586

1718

2587

1719

{

2588

1720

/* Work around Debian bug #633582:

2589

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

1721

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

2590

1722

2591

/* Re-raise privileges */

2592

ret = raise_privileges();

2593

if(ret != 0){

2594

errno = ret;

2595

perror_plus("Failed to raise privileges");

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

2596

1728

} else {

2597

1729

struct stat st;

2598

1730

2613

1745

}

2614

1746

}

2615

1747

}

2616

close(seckey_fd);

1748

TEMP_FAILURE_RETRY(close(seckey_fd));

2617

1749

}

2618

1750

}

2619

1751

2620

1752

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

2621

1753

int pubkey_fd = open(pubkey, O_RDONLY);

2622

1754

if(pubkey_fd == -1){

2634

1766

}

2635

1767

}

2636

1768

}

2637

close(pubkey_fd);

2638

}

2639

}

2640

2641

if(dh_params_file != NULL

2642

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

2643

int dhparams_fd = open(dh_params_file, O_RDONLY);

2644

if(dhparams_fd == -1){

2645

perror_plus("open");

2646

} else {

2647

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

2648

if(ret == -1){

2649

perror_plus("fstat");

2650

} else {

2651

if(S_ISREG(st.st_mode)

2652

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

2653

ret = fchown(dhparams_fd, uid, gid);

2654

if(ret == -1){

2655

perror_plus("fchown");

2656

}

2657

}

2658

}

2659

close(dhparams_fd);

2660

}

2661

}

2662

1769

TEMP_FAILURE_RETRY(close(pubkey_fd));

1770

}

1771

}

1772

2663

1773

/* Lower privileges */

2664

ret = lower_privileges();

2665

if(ret != 0){

2666

errno = ret;

2667

perror_plus("Failed to lower privileges");

2668

}

2669

}

2670

}

2671

2672

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

2673

{

2674

char *interface = NULL;

2675

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

2676

interface))){

2677

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

2678

and if_nametoindex(interface) == 0){

2679

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

2680

fprintf_plus(stderr, "Not using nonexisting interface"

2681

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

2682

}

2683

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

2684

interface = NULL;

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

2685

1778

}

2686

1779

}

2687

1780

}

2688

1781

2689

1782

/* Run network hooks */

2690

{

2691

if(mc.interfaces != NULL){

2692

interfaces_hooks = malloc(mc.interfaces_size);

2693

if(interfaces_hooks == NULL){

2694

perror_plus("malloc");

2695

goto end;

2696

}

2697

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

2698

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

2699

}

2700

run_network_hooks("start", interfaces_hooks != NULL ?

2701

interfaces_hooks : "", delay);

1783

if(not run_network_hooks("start", interface, delay)){

1784

goto end;

2702

1785

}

2703

1786

2704

1787

if(not debug){

2705

1788

avahi_set_log_function(empty_log);

2706

1789

}

2707

1790

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

/* No up interfaces, look for any good interfaces */

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

2708

1823

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

2709

1824

from the signal handler */

2710

1825

/* Initialize the pseudo-RNG for Avahi */

2711

1826

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

2712

simple_poll = avahi_simple_poll_new();

2713

if(simple_poll == NULL){

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2714

1829

fprintf_plus(stderr,

2715

1830

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

2716

1831

exitcode = EX_UNAVAILABLE;

2780

1895

}

2781

1896

}

2782

1897

2783

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

2784

if(mc.interfaces == NULL){

2785

struct dirent **direntries = NULL;

2786

/* Look for any good interfaces */

2787

ret = scandir(sys_class_net, &direntries, good_interface,

2788

alphasort);

2789

if(ret >= 1){

2790

/* Add all found interfaces to interfaces list */

2791

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

2792

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

2793

direntries[i]->d_name);

2794

if(ret_errno != 0){

2795

errno = ret_errno;

2796

perror_plus("argz_add");

2797

free(direntries[i]);

2798

continue;

2799

}

2800

if(debug){

2801

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

2802

direntries[i]->d_name);

2803

}

2804

free(direntries[i]);

2805

}

2806

free(direntries);

2807

} else {

2808

if(ret == 0){

2809

free(direntries);

2810

}

2811

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

2812

exitcode = EXIT_FAILURE;

2813

goto end;

2814

}

2815

}

2816

2817

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

2818

{

2819

char *interface = NULL;

2820

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

2821

interface))){

2822

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

2823

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

2824

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

2825

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

2826

interface);

2827

interface = NULL;

2828

while((interface = argz_next(mc.interfaces,

2829

mc.interfaces_size, interface))){

2830

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

2831

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

2832

interface);

2833

interface = NULL;

1898

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

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

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

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

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

2834

1983

}

2835

1984

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

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

1997

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

1998

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

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2836

2002

break;

2837

2003

}

2838

bool interface_was_up = interface_is_up(interface);

2839

errno = bring_up_interface(interface, delay);

2840

if(not interface_was_up){

2841

if(errno != 0){

2842

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

2843

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

2844

} else {

2845

errno = argz_add(&interfaces_to_take_down,

2846

&interfaces_to_take_down_size,

2847

interface);

2848

if(errno != 0){

2849

perror_plus("argz_add");

2850

}

2851

}

2852

}

2853

}

2854

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

2855

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

2856

}

2857

}

2858

2859

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

2860

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

2861

if(debug){

2862

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

2863

mc.interfaces);

2864

}

2865

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

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2866

2033

}

2867

2034

2868

2035

if(quit_now){

2869

2036

goto end;

2870

2037

}

2871

2038

2872

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

2039

ret = init_gnutls_global(pubkey, seckey);

2873

2040

if(ret == -1){

2874

2041

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

2875

2042

exitcode = EX_UNAVAILABLE;

2882

2049

goto end;

2883

2050

}

2884

2051

2885

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

2886

tempdir = mkdtemp(run_tempdir);

2887

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

2888

if(debug){

2889

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

2890

run_tempdir, old_tempdir);

2891

}

2892

tempdir = mkdtemp(old_tempdir);

2893

}

2894

if(tempdir == NULL){

2052

if(mkdtemp(tempdir) == NULL){

2895

2053

perror_plus("mkdtemp");

2896

2054

goto end;

2897

2055

}

2056

tempdir_created = true;

2898

2057

2899

2058

if(quit_now){

2900

2059

goto end;

2901

2060

}

2902

2061

2903

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

2062

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

2904

2063

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

2905

2064

exitcode = EX_UNAVAILABLE;

2906

2065

goto end;

2916

2075

/* Connect directly, do not use Zeroconf */

2917

2076

/* (Mainly meant for debugging) */

2918

2077

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

2919

2920

2078

if(address == NULL){

2921

2079

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

2922

2080

exitcode = EX_USAGE;

2927

2085

goto end;

2928

2086

}

2929

2087

2930

in_port_t port;

2088

uint16_t port;

2931

2089

errno = 0;

2932

2090

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

2933

2091

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

2934

or tmpmax != (in_port_t)tmpmax){

2092

or tmpmax != (uint16_t)tmpmax){

2935

2093

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

2936

2094

exitcode = EX_USAGE;

2937

2095

goto end;

2938

2096

}

2939

2097

2940

2098

if(quit_now){

2941

2099

goto end;

2942

2100

}

2943

2101

2944

port = (in_port_t)tmpmax;

2102

port = (uint16_t)tmpmax;

2945

2103

*address = '\0';

2946

2104

/* Colon in address indicates IPv6 */

2947

2105

int af;

2963

2121

}

2964

2122

2965

2123

while(not quit_now){

2966

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

2967

&mc);

2124

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

2968

2125

if(quit_now or ret == 0){

2969

2126

break;

2970

2127

}

2972

2129

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

2973

2130

(int)retry_interval);

2974

2131

}

2975

sleep((unsigned int)retry_interval);

2132

sleep((int)retry_interval);

2976

2133

}

2977

2134

2978

if(not quit_now){

2135

if (not quit_now){

2979

2136

exitcode = EXIT_SUCCESS;

2980

2137

}

2981

2138

2996

2153

config.publish_domain = 0;

2997

2154

2998

2155

/* Allocate a new server */

2999

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3000

&config, NULL, NULL, &ret);

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

3001

2159

3002

2160

/* Free the Avahi configuration data */

3003

2161

avahi_server_config_free(&config);

3006

2164

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

3007

2165

if(mc.server == NULL){

3008

2166

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

3009

avahi_strerror(ret));

2167

avahi_strerror(error));

3010

2168

exitcode = EX_UNAVAILABLE;

3011

2169

goto end;

3012

2170

}

3018

2176

/* Create the Avahi service browser */

3019

2177

sb = avahi_s_service_browser_new(mc.server, if_index,

3020

2178

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3021

NULL, 0, browse_callback,

3022

(void *)&mc);

2179

NULL, 0, browse_callback, NULL);

3023

2180

if(sb == NULL){

3024

2181

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

3025

2182

avahi_strerror(avahi_server_errno(mc.server)));

3036

2193

if(debug){

3037

2194

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

3038

2195

}

3039

3040

ret = avahi_loop_with_timeout(simple_poll,

3041

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

2196

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

3042

2199

if(debug){

3043

2200

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

3044

2201

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

3047

2204

end:

3048

2205

3049

2206

if(debug){

3050

if(signal_received){

3051

fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",

3052

argv[0], signal_received,

3053

strsignal(signal_received));

3054

} else {

3055

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

3056

}

2207

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

3057

2208

}

3058

2209

3059

2210

/* Cleanup things */

3060

free(mc.interfaces);

3061

3062

2211

if(sb != NULL)

3063

2212

avahi_s_service_browser_free(sb);

3064

2213

3065

2214

if(mc.server != NULL)

3066

2215

avahi_server_free(mc.server);

3067

2216

3068

if(simple_poll != NULL)

3069

avahi_simple_poll_free(simple_poll);

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

3070

2219

3071

2220

if(gnutls_initialized){

3072

2221

gnutls_certificate_free_credentials(mc.cred);

2222

gnutls_global_deinit();

3073

2223

gnutls_dh_params_deinit(mc.dh_params);

3074

2224

}

3075

2225

3083

2233

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

3084

2234

while(mc.current_server != NULL){

3085

2235

server *next = mc.current_server->next;

3086

#ifdef __GNUC__

3087

#pragma GCC diagnostic push

3088

#pragma GCC diagnostic ignored "-Wcast-qual"

3089

#endif

3090

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

3091

#ifdef __GNUC__

3092

#pragma GCC diagnostic pop

3093

#endif

3094

2236

free(mc.current_server);

3095

2237

mc.current_server = next;

3096

2238

}

3097

2239

}

3098

2240

3099

/* Re-raise privileges */

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

3100

2245

{

3101

ret = raise_privileges();

3102

if(ret != 0){

3103

errno = ret;

3104

perror_plus("Failed to raise privileges");

3105

} else {

3106

3107

/* Run network hooks */

3108

run_network_hooks("stop", interfaces_hooks != NULL ?

3109

interfaces_hooks : "", delay);

3110

3111

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

3112

{

3113

char *interface = NULL;

3114

while((interface = argz_next(interfaces_to_take_down,

3115

interfaces_to_take_down_size,

3116

interface))){

3117

ret = take_down_interface(interface);

3118

if(ret != 0){

3119

errno = ret;

3120

perror_plus("Failed to take down interface");

3121

}

3122

}

3123

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

3124

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

3125

" down\n");

3126

}

3127

}

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

3128

2250

}

3129

2251

3130

ret = lower_privileges_permanently();

3131

if(ret != 0){

3132

errno = ret;

3133

perror_plus("Failed to lower privileges permanently");

2252

/* Take down the network interface */

2253

if(take_down_interface and geteuid() == 0){

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

3134

2268

}

3135

2269

}

3136

3137

free(interfaces_to_take_down);

3138

free(interfaces_hooks);

3139

3140

void clean_dir_at(int base, const char * const dirname,

3141

uintmax_t level){

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2276

2277

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

2278

if(tempdir_created){

3142

2279

struct dirent **direntries = NULL;

3143

int dret;

3144

int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,

3145

O_RDONLY

3146

| O_NOFOLLOW

3147

| O_DIRECTORY

3148

| O_PATH));

3149

if(dir_fd == -1){

3150

perror_plus("open");

3151

return;

3152

}

3153

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

3154

notdotentries, alphasort);

3155

if(numentries >= 0){

2280

struct dirent *direntry = NULL;

2281

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

2282

alphasort);

2283

if (numentries > 0){

3156

2284

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

3157

if(debug){

3158

fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",

3159

dirname, direntries[i]->d_name);

3160

}

3161

dret = unlinkat(dir_fd, direntries[i]->d_name, 0);

3162

if(dret == -1){

3163

if(errno == EISDIR){

3164

dret = unlinkat(dir_fd, direntries[i]->d_name,

3165

AT_REMOVEDIR);

3166

}

3167

if((dret == -1) and (errno == ENOTEMPTY)

3168

and (strcmp(direntries[i]->d_name, "private-keys-v1.d")

3169

== 0) and (level == 0)){

3170

/* Recurse only in this special case */

3171

clean_dir_at(dir_fd, direntries[i]->d_name, level+1);

3172

dret = 0;

3173

}

3174

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

3175

fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,

3176

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

3177

}

3178

}

3179

free(direntries[i]);

3180

}

3181

3182

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

3183

free(direntries);

3184

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3185

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

3186

perror_plus("rmdir");

3187

}

3188

} else {

3189

perror_plus("scandirat");

3190

}

3191

close(dir_fd);

3192

}

3193

3194

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

3195

if(tempdir != NULL){

3196

clean_dir_at(-1, tempdir, 0);

2285

direntry = direntries[i];

2286

char *fullname = NULL;

2287

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

2288

direntry->d_name);

2289

if(ret < 0){

2290

perror_plus("asprintf");

2291

continue;

2292

}

2293

ret = remove(fullname);

2294

if(ret == -1){

2295

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

2296

strerror(errno));

2297

}

2298

free(fullname);

2299

}

2300

}

2301

2302

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

2303

free(direntries);

2304

if (numentries == -1){

2305

perror_plus("scandir");

2306

}

2307

ret = rmdir(tempdir);

2308

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

2309

perror_plus("rmdir");

2310

}

3197

2311

}

3198

2312

3199

2313

if(quit_now){