/mandos/release : revision 237.7.501

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

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*

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* Everything else is

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*

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

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

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* 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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*

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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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* 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 this program. If not, see

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

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

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*

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

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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

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

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stdout, ferror(), remove() */

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

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stdout, ferror() */

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

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

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

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strtof(), abort() */

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

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

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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sockaddr_in6, PF_INET6,

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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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strtoimax() */

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

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

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

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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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program_invocation_short_name */

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

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

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SIOCSIFFLAGS, if_indextoname(),

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if_nametoindex(), IF_NAMESIZE */

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*/

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

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

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setgid(), pause() */

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

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

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unlinkat() */

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

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

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

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argp_state, struct argp,

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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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init_gnutls_session(),

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GNUTLS_* */

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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/* GPGME */

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

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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

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bool debug = false;

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static const char mandos_protocol_version[] = "1";

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

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

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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struct server *next;

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struct server *prev;

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} server;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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gnutls_dh_params_t dh_params;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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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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}

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/*

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

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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){

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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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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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;

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}

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

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

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

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if(new_server == NULL){

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perror_plus("malloc");

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return false;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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free(new_server);

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return false;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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if(*current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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} 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->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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return true;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges(void){

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int old_errno = errno;

279

int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges_permanently(void){

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int old_errno = errno;

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int ret = raise_privileges();

292

if(ret != 0){

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errno = old_errno;

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return ret;

295

}

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

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int lower_privileges(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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/* Lower privileges permanently */

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__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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/*

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* Initialize GPGME.

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*/

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static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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/*

177

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

178

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*/

179

bool import_key(const char *filename){

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bool import_key(const char * const filename){

180

342

int ret;

181

343

int fd;

182

344

gpgme_data_t pgp_data;

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

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347

if(fd == -1){

186

perror("open");

348

perror_plus("open");

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return false;

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}

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/* Workaround for systems without a real-time clock; see also

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Debian bug #894495: <https://bugs.debian.org/894495> */

354

do {

355

{

356

time_t currtime = time(NULL);

357

if(currtime != (time_t)-1){

358

struct tm tm;

359

if(gmtime_r(&currtime, &tm) == NULL) {

360

perror_plus("gmtime_r");

361

break;

362

}

363

if(tm.tm_year != 70 or tm.tm_mon != 0){

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break;

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}

366

if(debug){

367

fprintf_plus(stderr, "System clock is January 1970");

368

}

369

} else {

370

if(debug){

371

fprintf_plus(stderr, "System clock is invalid");

372

}

373

}

374

}

375

struct stat keystat;

376

ret = fstat(fd, &keystat);

377

if(ret != 0){

378

perror_plus("fstat");

379

break;

380

}

381

ret = raise_privileges();

382

if(ret != 0){

383

errno = ret;

384

perror_plus("Failed to raise privileges");

385

break;

386

}

387

if(debug){

388

fprintf_plus(stderr,

389

"Setting system clock to key file mtime");

390

}

391

time_t keytime = keystat.st_mtim.tv_sec;

392

if(stime(&keytime) != 0){

393

perror_plus("stime");

394

}

395

ret = lower_privileges();

396

if(ret != 0){

397

errno = ret;

398

perror_plus("Failed to lower privileges");

399

}

400

} while(false);

401

190

402

rc = gpgme_data_new_from_fd(&pgp_data, fd);

191

403

if(rc != GPG_ERR_NO_ERROR){

192

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

193

gpgme_strsource(rc), gpgme_strerror(rc));

404

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

405

gpgme_strsource(rc), gpgme_strerror(rc));

194

406

return false;

195

407

}

196

408

197

rc = gpgme_op_import(mc.ctx, pgp_data);

409

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

198

410

if(rc != GPG_ERR_NO_ERROR){

199

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

200

gpgme_strsource(rc), gpgme_strerror(rc));

411

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

412

gpgme_strsource(rc), gpgme_strerror(rc));

201

413

return false;

202

414

}

415

{

416

gpgme_import_result_t import_result

417

= gpgme_op_import_result(mc->ctx);

418

if((import_result->imported < 1

419

or import_result->not_imported > 0)

420

and import_result->unchanged == 0){

421

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

422

fprintf_plus(stderr,

423

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

424

import_result->considered);

425

fprintf_plus(stderr,

426

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

427

import_result->no_user_id);

428

fprintf_plus(stderr,

429

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

430

import_result->imported);

431

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

432

import_result->imported_rsa);

433

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

434

import_result->unchanged);

435

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

436

import_result->new_user_ids);

437

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

438

import_result->new_sub_keys);

439

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

440

import_result->new_signatures);

441

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

442

import_result->new_revocations);

443

fprintf_plus(stderr,

444

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

445

import_result->secret_read);

446

fprintf_plus(stderr,

447

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

448

import_result->secret_imported);

449

fprintf_plus(stderr,

450

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

451

import_result->secret_unchanged);

452

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

453

import_result->not_imported);

454

for(gpgme_import_status_t import_status

455

= import_result->imports;

456

import_status != NULL;

457

import_status = import_status->next){

458

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

459

import_status->fpr);

460

if(import_status->result != GPG_ERR_NO_ERROR){

461

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

462

gpgme_strsource(import_status->result),

463

gpgme_strerror(import_status->result));

464

}

465

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

466

fprintf_plus(stderr,

467

import_status->status & GPGME_IMPORT_NEW

468

? "The key was new.\n"

469

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

470

fprintf_plus(stderr,

471

import_status->status & GPGME_IMPORT_UID

472

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

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_SIG

476

? "The key contained new signatures.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_SUBKEY

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SECRET

484

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

485

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

486

}

487

return false;

488

}

489

}

203

490

204

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

491

ret = close(fd);

205

492

if(ret == -1){

206

perror("close");

493

perror_plus("close");

207

494

}

208

495

gpgme_data_release(pgp_data);

209

496

return true;

210

497

}

211

498

212

499

if(debug){

213

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

500

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

214

501

}

215

502

216

503

/* Init GPGME */

217

504

gpgme_check_version(NULL);

218

505

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

219

506

if(rc != GPG_ERR_NO_ERROR){

220

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

221

gpgme_strsource(rc), gpgme_strerror(rc));

507

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

508

gpgme_strsource(rc), gpgme_strerror(rc));

222

509

return false;

223

510

}

224

511

225

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

512

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

226

513

rc = gpgme_get_engine_info(&engine_info);

227

514

if(rc != GPG_ERR_NO_ERROR){

228

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

229

gpgme_strsource(rc), gpgme_strerror(rc));

515

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

516

gpgme_strsource(rc), gpgme_strerror(rc));

230

517

return false;

231

518

}

232

519

while(engine_info != NULL){

238

525

engine_info = engine_info->next;

239

526

}

240

527

if(engine_info == NULL){

241

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

528

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

529

tempdir);

242

530

return false;

243

531

}

244

532

245

533

/* Create new GPGME "context" */

246

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

534

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

247

535

if(rc != GPG_ERR_NO_ERROR){

248

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

249

gpgme_strsource(rc), gpgme_strerror(rc));

536

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

537

gpgme_strsource(rc), gpgme_strerror(rc));

250

538

return false;

251

539

}

252

540

261

549

* Decrypt OpenPGP data.

262

550

* Returns -1 on error

263

551

*/

552

__attribute__((nonnull, warn_unused_result))

264

553

static ssize_t pgp_packet_decrypt(const char *cryptotext,

265

554

size_t crypto_size,

266

char **plaintext){

555

char **plaintext,

556

mandos_context *mc){

267

557

gpgme_data_t dh_crypto, dh_plain;

268

558

gpgme_error_t rc;

269

559

ssize_t ret;

271

561

ssize_t plaintext_length = 0;

272

562

273

563

if(debug){

274

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

564

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

275

565

}

276

566

277

567

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

278

568

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

279

569

0);

280

570

if(rc != GPG_ERR_NO_ERROR){

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

571

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

572

gpgme_strsource(rc), gpgme_strerror(rc));

283

573

return -1;

284

574

}

285

575

286

576

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

287

577

rc = gpgme_data_new(&dh_plain);

288

578

if(rc != GPG_ERR_NO_ERROR){

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

579

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

580

gpgme_strsource(rc), gpgme_strerror(rc));

291

581

gpgme_data_release(dh_crypto);

292

582

return -1;

293

583

}

294

584

295

585

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

296

586

data buffer */

297

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

587

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

298

588

if(rc != GPG_ERR_NO_ERROR){

299

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

300

gpgme_strsource(rc), gpgme_strerror(rc));

589

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

590

gpgme_strsource(rc), gpgme_strerror(rc));

301

591

plaintext_length = -1;

302

592

if(debug){

303

593

gpgme_decrypt_result_t result;

304

result = gpgme_op_decrypt_result(mc.ctx);

594

result = gpgme_op_decrypt_result(mc->ctx);

305

595

if(result == NULL){

306

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

596

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

307

597

} else {

308

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

309

result->unsupported_algorithm);

310

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

311

result->wrong_key_usage);

598

if(result->unsupported_algorithm != NULL) {

599

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

600

result->unsupported_algorithm);

601

}

602

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

603

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

312

604

if(result->file_name != NULL){

313

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

605

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

314

606

}

315

gpgme_recipient_t recipient;

316

recipient = result->recipients;

317

while(recipient != NULL){

318

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

319

gpgme_pubkey_algo_name(recipient->pubkey_algo));

320

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

321

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

322

recipient->status == GPG_ERR_NO_SECKEY

323

? "No" : "Yes");

324

recipient = recipient->next;

607

608

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

609

r = r->next){

610

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

611

gpgme_pubkey_algo_name(r->pubkey_algo));

612

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

613

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

614

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

325

615

}

326

616

}

327

617

}

329

619

}

330

620

331

621

if(debug){

332

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

622

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

333

623

}

334

624

335

625

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

336

626

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

337

perror("gpgme_data_seek");

627

perror_plus("gpgme_data_seek");

338

628

plaintext_length = -1;

339

629

goto decrypt_end;

340

630

}

342

632

*plaintext = NULL;

343

633

while(true){

344

634

plaintext_capacity = incbuffer(plaintext,

345

(size_t)plaintext_length,

346

plaintext_capacity);

635

(size_t)plaintext_length,

636

plaintext_capacity);

347

637

if(plaintext_capacity == 0){

348

perror("incbuffer");

349

plaintext_length = -1;

350

goto decrypt_end;

638

perror_plus("incbuffer");

639

plaintext_length = -1;

640

goto decrypt_end;

351

641

}

352

642

353

643

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

358

648

break;

359

649

}

360

650

if(ret < 0){

361

perror("gpgme_data_read");

651

perror_plus("gpgme_data_read");

362

652

plaintext_length = -1;

363

653

goto decrypt_end;

364

654

}

366

656

}

367

657

368

658

if(debug){

369

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

659

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

370

660

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

371

661

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

372

662

}

383

673

return plaintext_length;

384

674

}

385

675

386

static const char * safer_gnutls_strerror(int value){

387

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

388

-Wunreachable-code */

389

if(ret == NULL)

390

ret = "(unknown)";

391

return ret;

676

__attribute__((warn_unused_result, const))

677

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

678

if(str == NULL)

679

return "(unknown)";

680

return str;

681

}

682

683

__attribute__((warn_unused_result))

684

static const char *safer_gnutls_strerror(int value){

685

const char *ret = gnutls_strerror(value);

686

return safe_string(ret);

392

687

}

393

688

394

689

/* GnuTLS log function callback */

690

__attribute__((nonnull))

395

691

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

396

692

const char* string){

397

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

693

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

398

694

}

399

695

696

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

400

697

static int init_gnutls_global(const char *pubkeyfilename,

401

const char *seckeyfilename){

698

const char *seckeyfilename,

699

const char *dhparamsfilename,

700

mandos_context *mc){

402

701

int ret;

702

unsigned int uret;

403

703

404

704

if(debug){

405

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

406

}

407

408

ret = gnutls_global_init();

409

if(ret != GNUTLS_E_SUCCESS){

410

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

411

safer_gnutls_strerror(ret));

412

return -1;

705

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

413

706

}

414

707

415

708

if(debug){

421

714

}

422

715

423

716

/* OpenPGP credentials */

424

gnutls_certificate_allocate_credentials(&mc.cred);

717

ret = gnutls_certificate_allocate_credentials(&mc->cred);

425

718

if(ret != GNUTLS_E_SUCCESS){

426

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

427

from

428

-Wunreachable-code

429

*/

430

safer_gnutls_strerror(ret));

431

gnutls_global_deinit();

719

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

720

safer_gnutls_strerror(ret));

432

721

return -1;

433

722

}

434

723

435

724

if(debug){

436

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

437

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

438

seckeyfilename);

725

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

726

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

727

pubkeyfilename,

728

seckeyfilename);

439

729

}

440

730

441

731

ret = gnutls_certificate_set_openpgp_key_file

442

(mc.cred, pubkeyfilename, seckeyfilename,

732

(mc->cred, pubkeyfilename, seckeyfilename,

443

733

GNUTLS_OPENPGP_FMT_BASE64);

444

734

if(ret != GNUTLS_E_SUCCESS){

445

fprintf(stderr,

446

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

447

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

448

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

449

safer_gnutls_strerror(ret));

735

fprintf_plus(stderr,

736

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

737

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

738

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

739

safer_gnutls_strerror(ret));

450

740

goto globalfail;

451

741

}

452

742

453

743

/* GnuTLS server initialization */

454

ret = gnutls_dh_params_init(&mc.dh_params);

455

if(ret != GNUTLS_E_SUCCESS){

456

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

457

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

458

goto globalfail;

459

}

460

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

461

if(ret != GNUTLS_E_SUCCESS){

462

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

463

safer_gnutls_strerror(ret));

464

goto globalfail;

465

}

466

467

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

744

ret = gnutls_dh_params_init(&mc->dh_params);

745

if(ret != GNUTLS_E_SUCCESS){

746

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

747

" initialization: %s\n",

748

safer_gnutls_strerror(ret));

749

goto globalfail;

750

}

751

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

752

if(dhparamsfilename != NULL){

753

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

754

do {

755

int dhpfile = open(dhparamsfilename, O_RDONLY);

756

if(dhpfile == -1){

757

perror_plus("open");

758

dhparamsfilename = NULL;

759

break;

760

}

761

size_t params_capacity = 0;

762

while(true){

763

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

764

(size_t)params.size,

765

(size_t)params_capacity);

766

if(params_capacity == 0){

767

perror_plus("incbuffer");

768

free(params.data);

769

params.data = NULL;

770

dhparamsfilename = NULL;

771

break;

772

}

773

ssize_t bytes_read = read(dhpfile,

774

params.data + params.size,

775

BUFFER_SIZE);

776

/* EOF */

777

if(bytes_read == 0){

778

break;

779

}

780

/* check bytes_read for failure */

781

if(bytes_read < 0){

782

perror_plus("read");

783

free(params.data);

784

params.data = NULL;

785

dhparamsfilename = NULL;

786

break;

787

}

788

params.size += (unsigned int)bytes_read;

789

}

790

ret = close(dhpfile);

791

if(ret == -1){

792

perror_plus("close");

793

}

794

if(params.data == NULL){

795

dhparamsfilename = NULL;

796

}

797

if(dhparamsfilename == NULL){

798

break;

799

}

800

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

801

GNUTLS_X509_FMT_PEM);

802

if(ret != GNUTLS_E_SUCCESS){

803

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

804

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

805

safer_gnutls_strerror(ret));

806

dhparamsfilename = NULL;

807

}

808

free(params.data);

809

} while(false);

810

}

811

if(dhparamsfilename == NULL){

812

if(mc->dh_bits == 0){

813

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

814

/* Try to read the private key file */

815

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

816

do {

817

int secfile = open(seckeyfilename, O_RDONLY);

818

if(secfile == -1){

819

perror_plus("open");

820

break;

821

}

822

size_t buffer_capacity = 0;

823

while(true){

824

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

825

(size_t)buffer.size,

826

(size_t)buffer_capacity);

827

if(buffer_capacity == 0){

828

perror_plus("incbuffer");

829

free(buffer.data);

830

buffer.data = NULL;

831

break;

832

}

833

ssize_t bytes_read = read(secfile,

834

buffer.data + buffer.size,

835

BUFFER_SIZE);

836

/* EOF */

837

if(bytes_read == 0){

838

break;

839

}

840

/* check bytes_read for failure */

841

if(bytes_read < 0){

842

perror_plus("read");

843

free(buffer.data);

844

buffer.data = NULL;

845

break;

846

}

847

buffer.size += (unsigned int)bytes_read;

848

}

849

close(secfile);

850

} while(false);

851

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

852

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

853

if(buffer.data != NULL){

854

{

855

gnutls_openpgp_privkey_t privkey = NULL;

856

ret = gnutls_openpgp_privkey_init(&privkey);

857

if(ret != GNUTLS_E_SUCCESS){

858

fprintf_plus(stderr, "Error initializing OpenPGP key"

859

" structure: %s",

860

safer_gnutls_strerror(ret));

861

free(buffer.data);

862

buffer.data = NULL;

863

} else {

864

ret = gnutls_openpgp_privkey_import

865

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

866

if(ret != GNUTLS_E_SUCCESS){

867

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

868

safer_gnutls_strerror(ret));

869

privkey = NULL;

870

}

871

free(buffer.data);

872

buffer.data = NULL;

873

if(privkey != NULL){

874

/* Use private key to suggest an appropriate

875

sec_param */

876

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

877

gnutls_openpgp_privkey_deinit(privkey);

878

if(debug){

879

fprintf_plus(stderr, "This OpenPGP key implies using"

880

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

881

safe_string(gnutls_sec_param_get_name

882

(sec_param)));

883

}

884

}

885

}

886

}

887

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

888

/* Err on the side of caution */

889

sec_param = GNUTLS_SEC_PARAM_ULTRA;

890

if(debug){

891

fprintf_plus(stderr, "Falling back to security parameter"

892

" \"%s\"\n",

893

safe_string(gnutls_sec_param_get_name

894

(sec_param)));

895

}

896

}

897

}

898

uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

899

if(uret != 0){

900

mc->dh_bits = uret;

901

if(debug){

902

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

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)),

906

mc->dh_bits);

907

}

908

} else {

909

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

910

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

911

safe_string(gnutls_sec_param_get_name

912

(sec_param)),

913

safer_gnutls_strerror(ret));

914

goto globalfail;

915

}

916

} else if(debug){

917

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

918

mc->dh_bits);

919

}

920

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

921

if(ret != GNUTLS_E_SUCCESS){

922

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

923

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

924

safer_gnutls_strerror(ret));

925

goto globalfail;

926

}

927

}

928

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

468

929

469

930

return 0;

470

931

471

932

globalfail:

472

933

473

gnutls_certificate_free_credentials(mc.cred);

474

gnutls_global_deinit();

475

gnutls_dh_params_deinit(mc.dh_params);

934

gnutls_certificate_free_credentials(mc->cred);

935

gnutls_dh_params_deinit(mc->dh_params);

476

936

return -1;

477

937

}

478

938

479

static int init_gnutls_session(gnutls_session_t *session){

939

__attribute__((nonnull, warn_unused_result))

940

static int init_gnutls_session(gnutls_session_t *session,

941

mandos_context *mc){

480

942

int ret;

481

943

/* GnuTLS session creation */

482

944

do {

486

948

}

487

949

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

488

950

if(ret != GNUTLS_E_SUCCESS){

489

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

490

safer_gnutls_strerror(ret));

951

fprintf_plus(stderr,

952

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

953

safer_gnutls_strerror(ret));

491

954

}

492

955

493

956

{

494

957

const char *err;

495

958

do {

496

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

959

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

497

960

if(quit_now){

498

961

gnutls_deinit(*session);

499

962

return -1;

500

963

}

501

964

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

502

965

if(ret != GNUTLS_E_SUCCESS){

503

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

504

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

505

safer_gnutls_strerror(ret));

966

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

967

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

968

safer_gnutls_strerror(ret));

506

969

gnutls_deinit(*session);

507

970

return -1;

508

971

}

510

973

511

974

do {

512

975

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

513

mc.cred);

976

mc->cred);

514

977

if(quit_now){

515

978

gnutls_deinit(*session);

516

979

return -1;

517

980

}

518

981

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

519

982

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

983

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

984

safer_gnutls_strerror(ret));

522

985

gnutls_deinit(*session);

523

986

return -1;

524

987

}

526

989

/* ignore client certificate if any. */

527

990

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

528

991

529

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

530

531

992

return 0;

532

993

}

533

994

535

996

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

536

997

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

537

998

999

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

1000

__attribute__((nonnull, warn_unused_result))

1001

static bool add_delete_local_route(const bool add,

1002

const char *address,

1003

AvahiIfIndex if_index){

1004

int ret;

1005

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

1006

char add_arg[] = "add";

1007

char delete_arg[] = "delete";

1008

char debug_flag[] = "--debug";

1009

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1010

if(pluginhelperdir == NULL){

1011

if(debug){

1012

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1013

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

1014

}

1015

return false;

1016

}

1017

1018

char interface[IF_NAMESIZE];

1019

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

1020

perror_plus("if_indextoname");

1021

return false;

1022

}

1023

1024

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

1025

if(devnull == -1){

1026

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

1027

return false;

1028

}

1029

pid_t pid = fork();

1030

if(pid == 0){

1031

/* Child */

1032

/* Raise privileges */

1033

errno = raise_privileges_permanently();

1034

if(errno != 0){

1035

perror_plus("Failed to raise privileges");

1036

/* _exit(EX_NOPERM); */

1037

} else {

1038

/* Set group */

1039

errno = 0;

1040

ret = setgid(0);

1041

if(ret == -1){

1042

perror_plus("setgid");

1043

_exit(EX_NOPERM);

1044

}

1045

/* Reset supplementary groups */

1046

errno = 0;

1047

ret = setgroups(0, NULL);

1048

if(ret == -1){

1049

perror_plus("setgroups");

1050

_exit(EX_NOPERM);

1051

}

1052

}

1053

ret = dup2(devnull, STDIN_FILENO);

1054

if(ret == -1){

1055

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

1056

_exit(EX_OSERR);

1057

}

1058

ret = close(devnull);

1059

if(ret == -1){

1060

perror_plus("close");

1061

_exit(EX_OSERR);

1062

}

1063

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1064

if(ret == -1){

1065

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

1066

_exit(EX_OSERR);

1067

}

1068

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

1069

O_RDONLY

1070

| O_DIRECTORY

1071

| O_PATH

1072

| O_CLOEXEC));

1073

if(helperdir_fd == -1){

1074

perror_plus("open");

1075

_exit(EX_UNAVAILABLE);

1076

}

1077

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

1078

helper, O_RDONLY));

1079

if(helper_fd == -1){

1080

perror_plus("openat");

1081

close(helperdir_fd);

1082

_exit(EX_UNAVAILABLE);

1083

}

1084

close(helperdir_fd);

1085

#ifdef __GNUC__

1086

#pragma GCC diagnostic push

1087

#pragma GCC diagnostic ignored "-Wcast-qual"

1088

#endif

1089

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

1090

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

1091

interface, debug ? debug_flag : NULL, NULL },

1092

environ) == -1){

1093

#ifdef __GNUC__

1094

#pragma GCC diagnostic pop

1095

#endif

1096

perror_plus("fexecve");

1097

_exit(EXIT_FAILURE);

1098

}

1099

}

1100

if(pid == -1){

1101

perror_plus("fork");

1102

return false;

1103

}

1104

int status;

1105

pid_t pret = -1;

1106

errno = 0;

1107

do {

1108

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

1109

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

1110

int errno_raising = 0;

1111

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

1112

errno_raising = errno;

1113

perror_plus("Failed to raise privileges in order to"

1114

" kill helper program");

1115

}

1116

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

1117

perror_plus("kill");

1118

}

1119

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

1120

perror_plus("Failed to lower privileges after killing"

1121

" helper program");

1122

}

1123

return false;

1124

}

1125

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

1126

if(pret == -1){

1127

perror_plus("waitpid");

1128

return false;

1129

}

1130

if(WIFEXITED(status)){

1131

if(WEXITSTATUS(status) != 0){

1132

fprintf_plus(stderr, "Error: iprouteadddel exited"

1133

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

1134

return false;

1135

}

1136

return true;

1137

}

1138

if(WIFSIGNALED(status)){

1139

fprintf_plus(stderr, "Error: iprouteadddel died by"

1140

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

1141

return false;

1142

}

1143

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

1144

return false;

1145

}

1146

1147

__attribute__((nonnull, warn_unused_result))

1148

static bool add_local_route(const char *address,

1149

AvahiIfIndex if_index){

1150

if(debug){

1151

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

1152

}

1153

return add_delete_local_route(true, address, if_index);

1154

}

1155

1156

__attribute__((nonnull, warn_unused_result))

1157

static bool delete_local_route(const char *address,

1158

AvahiIfIndex if_index){

1159

if(debug){

1160

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

1161

}

1162

return add_delete_local_route(false, address, if_index);

1163

}

1164

538

1165

/* Called when a Mandos server is found */

539

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

1166

__attribute__((nonnull, warn_unused_result))

1167

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

540

1168

AvahiIfIndex if_index,

541

int af){

1169

int af, mandos_context *mc){

542

1170

int ret, tcp_sd = -1;

543

1171

ssize_t sret;

544

union {

545

struct sockaddr_in in;

546

struct sockaddr_in6 in6;

547

} to;

1172

struct sockaddr_storage to;

548

1173

char *buffer = NULL;

549

1174

char *decrypted_buffer = NULL;

550

1175

size_t buffer_length = 0;

553

1178

int retval = -1;

554

1179

gnutls_session_t session;

555

1180

int pf; /* Protocol family */

1181

bool route_added = false;

556

1182

557

1183

errno = 0;

558

1184

569

1195

pf = PF_INET;

570

1196

break;

571

1197

default:

572

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

1198

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

573

1199

errno = EINVAL;

574

1200

return -1;

575

1201

}

576

1202

577

ret = init_gnutls_session(&session);

1203

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

1204

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

1205

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

1206

bool match = false;

1207

{

1208

char *interface = NULL;

1209

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

1210

mc->interfaces_size,

1211

interface))){

1212

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

1213

match = true;

1214

break;

1215

}

1216

}

1217

}

1218

if(not match){

1219

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

1220

connect to the server */

1221

if(debug){

1222

char interface[IF_NAMESIZE];

1223

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

1224

perror_plus("if_indextoname");

1225

} else {

1226

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

1227

" \"%s\"\n",

1228

if_indextoname((unsigned int)if_index,

1229

interface));

1230

}

1231

}

1232

return -1;

1233

}

1234

}

1235

1236

ret = init_gnutls_session(&session, mc);

578

1237

if(ret != 0){

579

1238

return -1;

580

1239

}

581

1240

582

1241

if(debug){

583

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

584

"\n", ip, port);

1242

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

1243

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

585

1244

}

586

1245

587

tcp_sd = socket(pf, SOCK_STREAM, 0);

1246

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

588

1247

if(tcp_sd < 0){

589

1248

int e = errno;

590

perror("socket");

1249

perror_plus("socket");

591

1250

errno = e;

592

1251

goto mandos_end;

593

1252

}

597

1256

goto mandos_end;

598

1257

}

599

1258

600

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

601

1259

if(af == AF_INET6){

602

to.in6.sin6_family = (sa_family_t)af;

603

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

1260

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

1261

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

1262

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

604

1263

} else { /* IPv4 */

605

to.in.sin_family = (sa_family_t)af;

606

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

1264

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

1265

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

1266

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

607

1267

}

608

1268

if(ret < 0 ){

609

1269

int e = errno;

610

perror("inet_pton");

1270

perror_plus("inet_pton");

611

1271

errno = e;

612

1272

goto mandos_end;

613

1273

}

614

1274

if(ret == 0){

615

1275

int e = errno;

616

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

1276

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

617

1277

errno = e;

618

1278

goto mandos_end;

619

1279

}

620

1280

if(af == AF_INET6){

621

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

622

-Wconversion and

623

-Wunreachable-code */

624

625

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

626

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

627

-Wunreachable-code*/

1281

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

1282

if(IN6_IS_ADDR_LINKLOCAL

1283

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

628

1284

if(if_index == AVAHI_IF_UNSPEC){

629

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

630

" without a network interface\n");

1285

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

1286

" incomplete without a network interface\n");

631

1287

errno = EINVAL;

632

1288

goto mandos_end;

633

1289

}

634

1290

/* Set the network interface number as scope */

635

to.in6.sin6_scope_id = (uint32_t)if_index;

1291

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

636

1292

}

637

1293

} else {

638

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

639

-Wconversion and

640

-Wunreachable-code */

1294

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

641

1295

}

642

1296

643

1297

if(quit_now){

649

1303

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

650

1304

char interface[IF_NAMESIZE];

651

1305

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

652

perror("if_indextoname");

1306

perror_plus("if_indextoname");

653

1307

} else {

654

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

655

ip, interface, port);

1308

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

1309

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

656

1310

}

657

1311

} else {

658

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

659

port);

1312

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

1313

ip, (uintmax_t)port);

660

1314

}

661

1315

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

662

1316

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

663

const char *pcret;

664

if(af == AF_INET6){

665

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

666

sizeof(addrstr));

667

} else {

668

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

669

sizeof(addrstr));

670

}

671

if(pcret == NULL){

672

perror("inet_ntop");

673

} else {

674

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

675

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

676

}

677

}

678

}

679

680

if(quit_now){

681

errno = EINTR;

682

goto mandos_end;

683

}

684

685

if(af == AF_INET6){

686

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

687

} else {

688

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

689

}

690

if(ret < 0){

691

int e = errno;

692

perror("connect");

693

errno = e;

694

goto mandos_end;

695

}

696

697

if(quit_now){

698

errno = EINTR;

699

goto mandos_end;

1317

if(af == AF_INET6){

1318

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

1319

sizeof(struct sockaddr_in6),

1320

addrstr, sizeof(addrstr), NULL, 0,

1321

NI_NUMERICHOST);

1322

} else {

1323

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

1324

sizeof(struct sockaddr_in),

1325

addrstr, sizeof(addrstr), NULL, 0,

1326

NI_NUMERICHOST);

1327

}

1328

if(ret == EAI_SYSTEM){

1329

perror_plus("getnameinfo");

1330

} else if(ret != 0) {

1331

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

1332

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

1333

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

1334

}

1335

}

1336

1337

if(quit_now){

1338

errno = EINTR;

1339

goto mandos_end;

1340

}

1341

1342

while(true){

1343

if(af == AF_INET6){

1344

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

1345

sizeof(struct sockaddr_in6));

1346

} else {

1347

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

1348

sizeof(struct sockaddr_in));

1349

}

1350

if(ret < 0){

1351

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

1352

and if_index != AVAHI_IF_UNSPEC

1353

and connect_to == NULL

1354

and not route_added and

1355

((af == AF_INET6 and not

1356

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1357

&to)->sin6_addr)))

1358

or (af == AF_INET and

1359

/* Not a a IPv4LL address */

1360

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

1361

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

1362

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

1363

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

1364

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

1365

connect to a Mandos server announced by Avahi on a server

1366

host with a global address. Work around this by retrying

1367

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

1368

1369

Avahi bug reference:

1370

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

1371

https://bugs.debian.org/587961

1372

*/

1373

if(debug){

1374

fprintf_plus(stderr, "Mandos server unreachable, trying"

1375

" direct route\n");

1376

}

1377

int e = errno;

1378

route_added = add_local_route(ip, if_index);

1379

if(route_added){

1380

continue;

1381

}

1382

errno = e;

1383

}

1384

if(errno != ECONNREFUSED or debug){

1385

int e = errno;

1386

perror_plus("connect");

1387

errno = e;

1388

}

1389

goto mandos_end;

1390

}

1391

1392

if(quit_now){

1393

errno = EINTR;

1394

goto mandos_end;

1395

}

1396

break;

700

1397

}

701

1398

702

1399

const char *out = mandos_protocol_version;

704

1401

while(true){

705

1402

size_t out_size = strlen(out);

706

1403

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

707

out_size - written));

1404

out_size - written));

708

1405

if(ret == -1){

709

1406

int e = errno;

710

perror("write");

1407

perror_plus("write");

711

1408

errno = e;

712

1409

goto mandos_end;

713

1410

}

730

1427

}

731

1428

732

1429

if(debug){

733

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

1430

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

734

1431

}

735

1432

736

1433

if(quit_now){

738

1435

goto mandos_end;

739

1436

}

740

1437

741

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1438

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

1439

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

1440

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

1441

gnutls_transport_set_ptr(session,

1442

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

742

1443

743

1444

if(quit_now){

744

1445

errno = EINTR;

755

1456

756

1457

if(ret != GNUTLS_E_SUCCESS){

757

1458

if(debug){

758

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

1459

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

759

1460

gnutls_perror(ret);

760

1461

}

761

1462

errno = EPROTO;

765

1466

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

766

1467

767

1468

if(debug){

768

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

769

ip);

1469

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1470

" %s\n", ip);

770

1471

}

771

1472

772

1473

while(true){

777

1478

}

778

1479

779

1480

buffer_capacity = incbuffer(&buffer, buffer_length,

780

buffer_capacity);

1481

buffer_capacity);

781

1482

if(buffer_capacity == 0){

782

1483

int e = errno;

783

perror("incbuffer");

1484

perror_plus("incbuffer");

784

1485

errno = e;

785

1486

goto mandos_end;

786

1487

}

810

1511

}

811

1512

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

812

1513

if(ret < 0){

813

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

1514

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

1515

"***\n");

814

1516

gnutls_perror(ret);

815

1517

errno = EPROTO;

816

1518

goto mandos_end;

817

1519

}

818

1520

break;

819

1521

default:

820

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

821

" encrypted session with Mandos server\n");

1522

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

1523

" encrypted session with Mandos server\n");

822

1524

gnutls_bye(session, GNUTLS_SHUT_RDWR);

823

1525

errno = EIO;

824

1526

goto mandos_end;

829

1531

}

830

1532

831

1533

if(debug){

832

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

1534

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

833

1535

}

834

1536

835

1537

if(quit_now){

847

1549

848

1550

if(buffer_length > 0){

849

1551

ssize_t decrypted_buffer_size;

850

decrypted_buffer_size = pgp_packet_decrypt(buffer,

851

buffer_length,

852

&decrypted_buffer);

1552

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1553

&decrypted_buffer, mc);

853

1554

if(decrypted_buffer_size >= 0){

854

1555

1556

clearerr(stdout);

855

1557

written = 0;

856

1558

while(written < (size_t) decrypted_buffer_size){

857

1559

if(quit_now){

865

1567

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

866

1568

int e = errno;

867

1569

if(debug){

868

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

869

strerror(errno));

1570

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

1571

strerror(errno));

870

1572

}

871

1573

errno = e;

872

1574

goto mandos_end;

873

1575

}

874

1576

written += (size_t)ret;

875

1577

}

1578

ret = fflush(stdout);

1579

if(ret != 0){

1580

int e = errno;

1581

if(debug){

1582

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

1583

strerror(errno));

1584

}

1585

errno = e;

1586

goto mandos_end;

1587

}

876

1588

retval = 0;

877

1589

}

878

1590

}

881

1593

882

1594

mandos_end:

883

1595

{

1596

if(route_added){

1597

if(not delete_local_route(ip, if_index)){

1598

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

1599

" interface %d", ip, if_index);

1600

}

1601

}

884

1602

int e = errno;

885

1603

free(decrypted_buffer);

886

1604

free(buffer);

887

1605

if(tcp_sd >= 0){

888

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

1606

ret = close(tcp_sd);

889

1607

}

890

1608

if(ret == -1){

891

1609

if(e == 0){

892

1610

e = errno;

893

1611

}

894

perror("close");

1612

perror_plus("close");

895

1613

}

896

1614

gnutls_deinit(session);

1615

errno = e;

897

1616

if(quit_now){

898

e = EINTR;

1617

errno = EINTR;

899

1618

retval = -1;

900

1619

}

901

errno = e;

902

1620

}

903

1621

return retval;

904

1622

}

916

1634

AVAHI_GCC_UNUSED AvahiStringList *txt,

917

1635

AVAHI_GCC_UNUSED AvahiLookupResultFlags

918

1636

flags,

919

AVAHI_GCC_UNUSED void* userdata){

920

assert(r);

1637

void *mc){

1638

if(r == NULL){

1639

return;

1640

}

921

1641

922

1642

/* Called whenever a service has been resolved successfully or

923

1643

timed out */

924

1644

925

1645

if(quit_now){

1646

avahi_s_service_resolver_free(r);

926

1647

return;

927

1648

}

928

1649

929

1650

switch(event){

930

1651

default:

931

1652

case AVAHI_RESOLVER_FAILURE:

932

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

933

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

934

avahi_strerror(avahi_server_errno(mc.server)));

1653

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

1654

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

1655

domain,

1656

avahi_strerror(avahi_server_errno

1657

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

935

1658

break;

936

1659

937

1660

case AVAHI_RESOLVER_FOUND:

939

1662

char ip[AVAHI_ADDRESS_STR_MAX];

940

1663

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

941

1664

if(debug){

942

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

943

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

944

ip, (intmax_t)interface, port);

1665

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

1666

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

1667

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

945

1668

}

946

int ret = start_mandos_communication(ip, port, interface,

947

avahi_proto_to_af(proto));

1669

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

1670

interface,

1671

avahi_proto_to_af(proto),

1672

mc);

948

1673

if(ret == 0){

949

avahi_simple_poll_quit(mc.simple_poll);

1674

avahi_simple_poll_quit(simple_poll);

1675

} else {

1676

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

1677

avahi_proto_to_af(proto),

1678

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

1679

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

1680

" list\n", name);

1681

}

950

1682

}

951

1683

}

952

1684

}

962

1694

const char *domain,

963

1695

AVAHI_GCC_UNUSED AvahiLookupResultFlags

964

1696

flags,

965

AVAHI_GCC_UNUSED void* userdata){

966

assert(b);

1697

void *mc){

1698

if(b == NULL){

1699

return;

1700

}

967

1701

968

1702

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

969

1703

is removed from the LAN */

976

1710

default:

977

1711

case AVAHI_BROWSER_FAILURE:

978

1712

979

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

980

avahi_strerror(avahi_server_errno(mc.server)));

981

avahi_simple_poll_quit(mc.simple_poll);

1713

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

1714

avahi_strerror(avahi_server_errno

1715

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

1716

avahi_simple_poll_quit(simple_poll);

982

1717

return;

983

1718

984

1719

case AVAHI_BROWSER_NEW:

987

1722

the callback function is called the Avahi server will free the

988

1723

resolver for us. */

989

1724

990

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

991

name, type, domain, protocol, 0,

992

resolve_callback, NULL) == NULL)

993

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

994

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

1725

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

1726

interface, protocol, name, type,

1727

domain, protocol, 0,

1728

resolve_callback, mc) == NULL)

1729

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

1730

" %s\n", name,

1731

avahi_strerror(avahi_server_errno

1732

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

995

1733

break;

996

1734

997

1735

case AVAHI_BROWSER_REMOVE:

1000

1738

case AVAHI_BROWSER_ALL_FOR_NOW:

1001

1739

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1002

1740

if(debug){

1003

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

1741

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

1742

" searching...\n");

1004

1743

}

1005

1744

break;

1006

1745

}

1007

1746

}

1008

1747

1009

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

1748

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

1010

1749

static void handle_sigterm(int sig){

1011

1750

if(quit_now){

1012

1751

return;

1014

1753

quit_now = 1;

1015

1754

signal_received = sig;

1016

1755

int old_errno = errno;

1017

if(mc.simple_poll != NULL){

1018

avahi_simple_poll_quit(mc.simple_poll);

1019

}

1020

errno = old_errno;

1756

/* set main loop to exit */

1757

if(simple_poll != NULL){

1758

avahi_simple_poll_quit(simple_poll);

1759

}

1760

errno = old_errno;

1761

}

1762

1763

__attribute__((nonnull, warn_unused_result))

1764

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

1765

int ret;

1766

int old_errno;

1767

1768

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

1769

if(s < 0){

1770

old_errno = errno;

1771

perror_plus("socket");

1772

errno = old_errno;

1773

return false;

1774

}

1775

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

1776

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

1777

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1778

if(ret == -1){

1779

if(debug){

1780

old_errno = errno;

1781

perror_plus("ioctl SIOCGIFFLAGS");

1782

errno = old_errno;

1783

}

1784

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

1785

old_errno = errno;

1786

perror_plus("close");

1787

errno = old_errno;

1788

}

1789

return false;

1790

}

1791

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

1792

old_errno = errno;

1793

perror_plus("close");

1794

errno = old_errno;

1795

}

1796

return true;

1797

}

1798

1799

__attribute__((nonnull, warn_unused_result))

1800

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

1801

1802

/* Reject the loopback device */

1803

if(ifr->ifr_flags & IFF_LOOPBACK){

1804

if(debug){

1805

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

1806

ifname);

1807

}

1808

return false;

1809

}

1810

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

1811

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

1812

if(debug){

1813

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

1814

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

1815

}

1816

return true;

1817

}

1818

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

1819

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

1820

if(debug){

1821

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1822

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

1823

}

1824

return false;

1825

}

1826

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

1827

if(ifr->ifr_flags & IFF_NOARP){

1828

if(debug){

1829

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

1830

ifname);

1831

}

1832

return false;

1833

}

1834

1835

/* Accept this device */

1836

if(debug){

1837

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

1838

}

1839

return true;

1840

}

1841

1842

/*

1843

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

1844

* corresponds to an acceptable network device.

1845

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

1846

*/

1847

__attribute__((nonnull, warn_unused_result))

1848

int good_interface(const struct dirent *if_entry){

1849

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

1850

return 0;

1851

}

1852

1853

struct ifreq ifr;

1854

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

1855

if(debug){

1856

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

1857

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

1858

}

1859

return 0;

1860

}

1861

1862

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

1863

return 0;

1864

}

1865

return 1;

1866

}

1867

1868

/*

1869

* This function determines if a network interface is up.

1870

*/

1871

__attribute__((nonnull, warn_unused_result))

1872

bool interface_is_up(const char *interface){

1873

struct ifreq ifr;

1874

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

1875

if(debug){

1876

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

1877

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

1878

}

1879

return false;

1880

}

1881

1882

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

1883

}

1884

1885

/*

1886

* This function determines if a network interface is running

1887

*/

1888

__attribute__((nonnull, warn_unused_result))

1889

bool interface_is_running(const char *interface){

1890

struct ifreq ifr;

1891

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

1892

if(debug){

1893

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

1894

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

1895

}

1896

return false;

1897

}

1898

1899

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

1900

}

1901

1902

__attribute__((nonnull, pure, warn_unused_result))

1903

int notdotentries(const struct dirent *direntry){

1904

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

1905

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

1906

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

1907

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

1908

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

1909

return 0;

1910

}

1911

return 1;

1912

}

1913

1914

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

1915

__attribute__((nonnull, warn_unused_result))

1916

int runnable_hook(const struct dirent *direntry){

1917

int ret;

1918

size_t sret;

1919

struct stat st;

1920

1921

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

1922

/* Empty name? */

1923

return 0;

1924

}

1925

1926

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

1927

"abcdefghijklmnopqrstuvwxyz"

1928

"0123456789"

1929

"_.-");

1930

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

1931

/* Contains non-allowed characters */

1932

if(debug){

1933

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

1934

direntry->d_name);

1935

}

1936

return 0;

1937

}

1938

1939

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

1940

if(ret == -1){

1941

if(debug){

1942

perror_plus("Could not stat hook");

1943

}

1944

return 0;

1945

}

1946

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

1947

/* Not a regular file */

1948

if(debug){

1949

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

1950

direntry->d_name);

1951

}

1952

return 0;

1953

}

1954

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

1955

/* Not executable */

1956

if(debug){

1957

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

1958

direntry->d_name);

1959

}

1960

return 0;

1961

}

1962

if(debug){

1963

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

1964

direntry->d_name);

1965

}

1966

return 1;

1967

}

1968

1969

__attribute__((nonnull, warn_unused_result))

1970

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

1971

mandos_context *mc){

1972

int ret;

1973

struct timespec now;

1974

struct timespec waited_time;

1975

intmax_t block_time;

1976

1977

while(true){

1978

if(mc->current_server == NULL){

1979

if(debug){

1980

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

1981

" No timeout!\n");

1982

}

1983

ret = avahi_simple_poll_iterate(s, -1);

1984

} else {

1985

if(debug){

1986

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

1987

" it, or wait\n");

1988

}

1989

/* the current time */

1990

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1991

if(ret == -1){

1992

perror_plus("clock_gettime");

1993

return -1;

1994

}

1995

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

1996

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

1997

waited_time.tv_sec = (now.tv_sec

1998

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

1999

waited_time.tv_nsec = (now.tv_nsec

2000

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

2001

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

2002

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

2003

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

2004

block_time = ((retry_interval

2005

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

2006

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

2007

2008

if(debug){

2009

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

2010

block_time);

2011

}

2012

2013

if(block_time <= 0){

2014

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

2015

mc->current_server->port,

2016

mc->current_server->if_index,

2017

mc->current_server->af, mc);

2018

if(ret == 0){

2019

avahi_simple_poll_quit(s);

2020

return 0;

2021

}

2022

ret = clock_gettime(CLOCK_MONOTONIC,

2023

&mc->current_server->last_seen);

2024

if(ret == -1){

2025

perror_plus("clock_gettime");

2026

return -1;

2027

}

2028

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

2029

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

2030

servers, but don't block */

2031

}

2032

2033

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

2034

}

2035

if(ret != 0){

2036

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

2037

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

2038

}

2039

}

2040

}

2041

}

2042

2043

__attribute__((nonnull))

2044

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

2045

const float delay){

2046

struct dirent **direntries = NULL;

2047

if(hookdir_fd == -1){

2048

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2049

| O_CLOEXEC);

2050

if(hookdir_fd == -1){

2051

if(errno == ENOENT){

2052

if(debug){

2053

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

2054

" found\n", hookdir);

2055

}

2056

} else {

2057

perror_plus("open");

2058

}

2059

return;

2060

}

2061

}

2062

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

2063

if(devnull == -1){

2064

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

2065

return;

2066

}

2067

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

2068

runnable_hook, alphasort);

2069

if(numhooks == -1){

2070

perror_plus("scandir");

2071

close(devnull);

2072

return;

2073

}

2074

struct dirent *direntry;

2075

int ret;

2076

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

2077

direntry = direntries[i];

2078

if(debug){

2079

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

2080

direntry->d_name);

2081

}

2082

pid_t hook_pid = fork();

2083

if(hook_pid == 0){

2084

/* Child */

2085

/* Raise privileges */

2086

errno = raise_privileges_permanently();

2087

if(errno != 0){

2088

perror_plus("Failed to raise privileges");

2089

_exit(EX_NOPERM);

2090

}

2091

/* Set group */

2092

errno = 0;

2093

ret = setgid(0);

2094

if(ret == -1){

2095

perror_plus("setgid");

2096

_exit(EX_NOPERM);

2097

}

2098

/* Reset supplementary groups */

2099

errno = 0;

2100

ret = setgroups(0, NULL);

2101

if(ret == -1){

2102

perror_plus("setgroups");

2103

_exit(EX_NOPERM);

2104

}

2105

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

2106

if(ret == -1){

2107

perror_plus("setenv");

2108

_exit(EX_OSERR);

2109

}

2110

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

2111

if(ret == -1){

2112

perror_plus("setenv");

2113

_exit(EX_OSERR);

2114

}

2115

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

2116

if(ret == -1){

2117

perror_plus("setenv");

2118

_exit(EX_OSERR);

2119

}

2120

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

2121

if(ret == -1){

2122

perror_plus("setenv");

2123

_exit(EX_OSERR);

2124

}

2125

char *delaystring;

2126

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

2127

if(ret == -1){

2128

perror_plus("asprintf");

2129

_exit(EX_OSERR);

2130

}

2131

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

2132

if(ret == -1){

2133

free(delaystring);

2134

perror_plus("setenv");

2135

_exit(EX_OSERR);

2136

}

2137

free(delaystring);

2138

if(connect_to != NULL){

2139

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

2140

if(ret == -1){

2141

perror_plus("setenv");

2142

_exit(EX_OSERR);

2143

}

2144

}

2145

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

2146

direntry->d_name,

2147

O_RDONLY));

2148

if(hook_fd == -1){

2149

perror_plus("openat");

2150

_exit(EXIT_FAILURE);

2151

}

2152

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

2153

perror_plus("close");

2154

_exit(EXIT_FAILURE);

2155

}

2156

ret = dup2(devnull, STDIN_FILENO);

2157

if(ret == -1){

2158

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

2159

_exit(EX_OSERR);

2160

}

2161

ret = close(devnull);

2162

if(ret == -1){

2163

perror_plus("close");

2164

_exit(EX_OSERR);

2165

}

2166

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2167

if(ret == -1){

2168

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

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

environ) == -1){

2173

perror_plus("fexecve");

2174

_exit(EXIT_FAILURE);

2175

}

2176

} else {

2177

if(hook_pid == -1){

2178

perror_plus("fork");

2179

free(direntry);

2180

continue;

2181

}

2182

int status;

2183

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

2184

perror_plus("waitpid");

2185

free(direntry);

2186

continue;

2187

}

2188

if(WIFEXITED(status)){

2189

if(WEXITSTATUS(status) != 0){

2190

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

2191

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

2192

WEXITSTATUS(status));

2193

free(direntry);

2194

continue;

2195

}

2196

} else if(WIFSIGNALED(status)){

2197

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

2198

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

2199

WTERMSIG(status));

2200

free(direntry);

2201

continue;

2202

} else {

2203

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

2204

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

2205

free(direntry);

2206

continue;

2207

}

2208

}

2209

if(debug){

2210

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

2211

direntry->d_name);

2212

}

2213

free(direntry);

2214

}

2215

free(direntries);

2216

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

2217

perror_plus("close");

2218

} else {

2219

hookdir_fd = -1;

2220

}

2221

close(devnull);

2222

}

2223

2224

__attribute__((nonnull, warn_unused_result))

2225

int bring_up_interface(const char *const interface,

2226

const float delay){

2227

int old_errno = errno;

2228

int ret;

2229

struct ifreq network;

2230

unsigned int if_index = if_nametoindex(interface);

2231

if(if_index == 0){

2232

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

2233

errno = old_errno;

2234

return ENXIO;

2235

}

2236

2237

if(quit_now){

2238

errno = old_errno;

2239

return EINTR;

2240

}

2241

2242

if(not interface_is_up(interface)){

2243

int ret_errno = 0;

2244

int ioctl_errno = 0;

2245

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

2246

ret_errno = errno;

2247

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

2248

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

2249

errno = old_errno;

2250

return ret_errno;

2251

}

2252

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

2253

2254

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

2255

if(sd == -1){

2256

ret_errno = errno;

2257

perror_plus("socket");

2258

errno = old_errno;

2259

return ret_errno;

2260

}

2261

2262

if(quit_now){

2263

ret = close(sd);

2264

if(ret == -1){

2265

perror_plus("close");

2266

}

2267

errno = old_errno;

2268

return EINTR;

2269

}

2270

2271

if(debug){

2272

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

2273

interface);

2274

}

2275

2276

/* Raise privileges */

2277

ret_errno = raise_privileges();

2278

if(ret_errno != 0){

2279

errno = ret_errno;

2280

perror_plus("Failed to raise privileges");

2281

}

2282

2283

#ifdef __linux__

2284

int ret_linux;

2285

bool restore_loglevel = false;

2286

if(ret_errno == 0){

2287

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2288

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

2289

ret_linux = klogctl(8, NULL, 5);

2290

if(ret_linux == -1){

2291

perror_plus("klogctl");

2292

} else {

2293

restore_loglevel = true;

2294

}

2295

}

2296

#endif /* __linux__ */

2297

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

2298

ioctl_errno = errno;

2299

#ifdef __linux__

2300

if(restore_loglevel){

2301

ret_linux = klogctl(7, NULL, 0);

2302

if(ret_linux == -1){

2303

perror_plus("klogctl");

2304

}

2305

}

2306

#endif /* __linux__ */

2307

2308

/* If raise_privileges() succeeded above */

2309

if(ret_errno == 0){

2310

/* Lower privileges */

2311

ret_errno = lower_privileges();

2312

if(ret_errno != 0){

2313

errno = ret_errno;

2314

perror_plus("Failed to lower privileges");

2315

}

2316

}

2317

2318

/* Close the socket */

2319

ret = close(sd);

2320

if(ret == -1){

2321

perror_plus("close");

2322

}

2323

2324

if(ret_setflags == -1){

2325

errno = ioctl_errno;

2326

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2327

errno = old_errno;

2328

return ioctl_errno;

2329

}

2330

} else if(debug){

2331

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

2332

interface);

2333

}

2334

2335

/* Sleep checking until interface is running.

2336

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

2337

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

2338

if(interface_is_running(interface)){

2339

break;

2340

}

2341

struct timespec sleeptime = { .tv_nsec = 250000000 };

2342

ret = nanosleep(&sleeptime, NULL);

2343

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

2344

perror_plus("nanosleep");

2345

}

2346

}

2347

2348

errno = old_errno;

2349

return 0;

2350

}

2351

2352

__attribute__((nonnull, warn_unused_result))

2353

int take_down_interface(const char *const interface){

2354

int old_errno = errno;

2355

struct ifreq network;

2356

unsigned int if_index = if_nametoindex(interface);

2357

if(if_index == 0){

2358

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

2359

errno = old_errno;

2360

return ENXIO;

2361

}

2362

if(interface_is_up(interface)){

2363

int ret_errno = 0;

2364

int ioctl_errno = 0;

2365

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

2366

ret_errno = errno;

2367

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

2368

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

2369

errno = old_errno;

2370

return ret_errno;

2371

}

2372

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

2373

2374

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

2375

if(sd == -1){

2376

ret_errno = errno;

2377

perror_plus("socket");

2378

errno = old_errno;

2379

return ret_errno;

2380

}

2381

2382

if(debug){

2383

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

2384

interface);

2385

}

2386

2387

/* Raise privileges */

2388

ret_errno = raise_privileges();

2389

if(ret_errno != 0){

2390

errno = ret_errno;

2391

perror_plus("Failed to raise privileges");

2392

}

2393

2394

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

2395

ioctl_errno = errno;

2396

2397

/* If raise_privileges() succeeded above */

2398

if(ret_errno == 0){

2399

/* Lower privileges */

2400

ret_errno = lower_privileges();

2401

if(ret_errno != 0){

2402

errno = ret_errno;

2403

perror_plus("Failed to lower privileges");

2404

}

2405

}

2406

2407

/* Close the socket */

2408

int ret = close(sd);

2409

if(ret == -1){

2410

perror_plus("close");

2411

}

2412

2413

if(ret_setflags == -1){

2414

errno = ioctl_errno;

2415

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2416

errno = old_errno;

2417

return ioctl_errno;

2418

}

2419

} else if(debug){

2420

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

2421

interface);

2422

}

2423

2424

errno = old_errno;

2425

return 0;

1021

2426

}

1022

2427

1023

2428

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

2429

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

2430

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

2431

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

2432

.current_server = NULL, .interfaces = NULL,

2433

.interfaces_size = 0 };

1024

2434

AvahiSServiceBrowser *sb = NULL;

1025

int error;

2435

error_t ret_errno;

1026

2436

int ret;

1027

2437

intmax_t tmpmax;

1028

2438

char *tmp;

1029

2439

int exitcode = EXIT_SUCCESS;

1030

const char *interface = "eth0";

1031

struct ifreq network;

1032

int sd = -1;

1033

bool take_down_interface = false;

1034

uid_t uid;

1035

gid_t gid;

1036

char *connect_to = NULL;

1037

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

1038

bool tempdir_created = false;

2440

char *interfaces_to_take_down = NULL;

2441

size_t interfaces_to_take_down_size = 0;

2442

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

2443

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

2444

char *tempdir = NULL;

1039

2445

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1040

2446

const char *seckey = PATHDIR "/" SECKEY;

1041

2447

const char *pubkey = PATHDIR "/" PUBKEY;

2448

const char *dh_params_file = NULL;

2449

char *interfaces_hooks = NULL;

1042

2450

1043

2451

bool gnutls_initialized = false;

1044

2452

bool gpgme_initialized = false;

1045

2453

float delay = 2.5f;

2454

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

2455

retrying the same server again */

1046

2456

1047

2457

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1048

2458

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1054

2464

errno = 0;

1055

2465

ret = setgid(gid);

1056

2466

if(ret == -1){

1057

perror("setgid");

2467

perror_plus("setgid");

1058

2468

}

1059

2469

1060

2470

/* Lower user privileges (temporarily) */

1061

2471

errno = 0;

1062

2472

ret = seteuid(uid);

1063

2473

if(ret == -1){

1064

perror("seteuid");

2474

perror_plus("seteuid");

1065

2475

}

1066

2476

1067

2477

if(quit_now){

1094

2504

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

1095

2505

" Diffie-Hellman key exchange",

1096

2506

.group = 2 },

2507

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

2508

.arg = "FILE",

2509

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

2510

" for the Diffie-Hellman key exchange",

2511

.group = 2 },

1097

2512

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

1098

2513

.arg = "STRING",

1099

2514

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

1102

2517

.arg = "SECONDS",

1103

2518

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

1104

2519

.group = 2 },

2520

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

2521

.arg = "SECONDS",

2522

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

2523

.group = 2 },

2524

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

2525

.arg = "DIR",

2526

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

2527

.group = 2 },

1105

2528

/*

1106

2529

* These reproduce what we would get without ARGP_NO_HELP

1107

2530

*/

1125

2548

connect_to = arg;

1126

2549

break;

1127

2550

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

1128

interface = arg;

2551

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

2552

arg, (int)',');

2553

if(ret_errno != 0){

2554

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

2555

}

1129

2556

break;

1130

2557

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

1131

2558

seckey = arg;

1142

2569

}

1143

2570

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

1144

2571

break;

2572

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

2573

dh_params_file = arg;

2574

break;

1145

2575

case 130: /* --priority */

1146

2576

mc.priority = arg;

1147

2577

break;

1151

2581

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

1152

2582

argp_error(state, "Bad delay");

1153

2583

}

2584

case 132: /* --retry */

2585

errno = 0;

2586

retry_interval = strtod(arg, &tmp);

2587

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

2588

or (retry_interval * 1000) > INT_MAX

2589

or retry_interval < 0){

2590

argp_error(state, "Bad retry interval");

2591

}

2592

break;

2593

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

2594

hookdir = arg;

1154

2595

break;

1155

2596

/*

1156

2597

* These reproduce what we would get without ARGP_NO_HELP

1163

2604

argp_state_help(state, state->out_stream,

1164

2605

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1165

2606

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

1166

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

2607

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

1167

2608

exit(argp_err_exit_status);

1168

2609

break;

1169

2610

default:

1176

2617

.args_doc = "",

1177

2618

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

1178

2619

" passwords from a Mandos server" };

1179

ret = argp_parse(&argp, argc, argv,

1180

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1181

switch(ret){

2620

ret_errno = argp_parse(&argp, argc, argv,

2621

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2622

switch(ret_errno){

1182

2623

case 0:

1183

2624

break;

1184

2625

case ENOMEM:

1185

2626

default:

1186

errno = ret;

1187

perror("argp_parse");

2627

errno = ret_errno;

2628

perror_plus("argp_parse");

1188

2629

exitcode = EX_OSERR;

1189

2630

goto end;

1190

2631

case EINVAL:

1193

2634

}

1194

2635

}

1195

2636

2637

{

2638

/* Work around Debian bug #633582:

2639

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

2640

2641

/* Re-raise privileges */

2642

ret = raise_privileges();

2643

if(ret != 0){

2644

errno = ret;

2645

perror_plus("Failed to raise privileges");

2646

} else {

2647

struct stat st;

2648

2649

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

2650

int seckey_fd = open(seckey, O_RDONLY);

2651

if(seckey_fd == -1){

2652

perror_plus("open");

2653

} else {

2654

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

2655

if(ret == -1){

2656

perror_plus("fstat");

2657

} else {

2658

if(S_ISREG(st.st_mode)

2659

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

2660

ret = fchown(seckey_fd, uid, gid);

2661

if(ret == -1){

2662

perror_plus("fchown");

2663

}

2664

}

2665

}

2666

close(seckey_fd);

2667

}

2668

}

2669

2670

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

2671

int pubkey_fd = open(pubkey, O_RDONLY);

2672

if(pubkey_fd == -1){

2673

perror_plus("open");

2674

} else {

2675

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

2676

if(ret == -1){

2677

perror_plus("fstat");

2678

} else {

2679

if(S_ISREG(st.st_mode)

2680

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

2681

ret = fchown(pubkey_fd, uid, gid);

2682

if(ret == -1){

2683

perror_plus("fchown");

2684

}

2685

}

2686

}

2687

close(pubkey_fd);

2688

}

2689

}

2690

2691

if(dh_params_file != NULL

2692

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

2693

int dhparams_fd = open(dh_params_file, O_RDONLY);

2694

if(dhparams_fd == -1){

2695

perror_plus("open");

2696

} else {

2697

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

2698

if(ret == -1){

2699

perror_plus("fstat");

2700

} else {

2701

if(S_ISREG(st.st_mode)

2702

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

2703

ret = fchown(dhparams_fd, uid, gid);

2704

if(ret == -1){

2705

perror_plus("fchown");

2706

}

2707

}

2708

}

2709

close(dhparams_fd);

2710

}

2711

}

2712

2713

/* Lower privileges */

2714

ret = lower_privileges();

2715

if(ret != 0){

2716

errno = ret;

2717

perror_plus("Failed to lower privileges");

2718

}

2719

}

2720

}

2721

2722

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

2723

{

2724

char *interface = NULL;

2725

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

2726

interface))){

2727

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

2728

and if_nametoindex(interface) == 0){

2729

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

2730

fprintf_plus(stderr, "Not using nonexisting interface"

2731

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

2732

}

2733

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

2734

interface = NULL;

2735

}

2736

}

2737

}

2738

2739

/* Run network hooks */

2740

{

2741

if(mc.interfaces != NULL){

2742

interfaces_hooks = malloc(mc.interfaces_size);

2743

if(interfaces_hooks == NULL){

2744

perror_plus("malloc");

2745

goto end;

2746

}

2747

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

2748

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

2749

}

2750

run_network_hooks("start", interfaces_hooks != NULL ?

2751

interfaces_hooks : "", delay);

2752

}

2753

1196

2754

if(not debug){

1197

2755

avahi_set_log_function(empty_log);

1198

2756

}

1201

2759

from the signal handler */

1202

2760

/* Initialize the pseudo-RNG for Avahi */

1203

2761

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

1204

mc.simple_poll = avahi_simple_poll_new();

1205

if(mc.simple_poll == NULL){

1206

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

2762

simple_poll = avahi_simple_poll_new();

2763

if(simple_poll == NULL){

2764

fprintf_plus(stderr,

2765

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

1207

2766

exitcode = EX_UNAVAILABLE;

1208

2767

goto end;

1209

2768

}

1211

2770

sigemptyset(&sigterm_action.sa_mask);

1212

2771

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

1213

2772

if(ret == -1){

1214

perror("sigaddset");

2773

perror_plus("sigaddset");

1215

2774

exitcode = EX_OSERR;

1216

2775

goto end;

1217

2776

}

1218

2777

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

1219

2778

if(ret == -1){

1220

perror("sigaddset");

2779

perror_plus("sigaddset");

1221

2780

exitcode = EX_OSERR;

1222

2781

goto end;

1223

2782

}

1224

2783

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

1225

2784

if(ret == -1){

1226

perror("sigaddset");

2785

perror_plus("sigaddset");

1227

2786

exitcode = EX_OSERR;

1228

2787

goto end;

1229

2788

}

1233

2792

*/

1234

2793

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

1235

2794

if(ret == -1){

1236

perror("sigaction");

2795

perror_plus("sigaction");

1237

2796

return EX_OSERR;

1238

2797

}

1239

2798

if(old_sigterm_action.sa_handler != SIG_IGN){

1240

2799

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

1241

2800

if(ret == -1){

1242

perror("sigaction");

2801

perror_plus("sigaction");

1243

2802

exitcode = EX_OSERR;

1244

2803

goto end;

1245

2804

}

1246

2805

}

1247

2806

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

1248

2807

if(ret == -1){

1249

perror("sigaction");

2808

perror_plus("sigaction");

1250

2809

return EX_OSERR;

1251

2810

}

1252

2811

if(old_sigterm_action.sa_handler != SIG_IGN){

1253

2812

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

1254

2813

if(ret == -1){

1255

perror("sigaction");

2814

perror_plus("sigaction");

1256

2815

exitcode = EX_OSERR;

1257

2816

goto end;

1258

2817

}

1259

2818

}

1260

2819

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

1261

2820

if(ret == -1){

1262

perror("sigaction");

2821

perror_plus("sigaction");

1263

2822

return EX_OSERR;

1264

2823

}

1265

2824

if(old_sigterm_action.sa_handler != SIG_IGN){

1266

2825

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

1267

2826

if(ret == -1){

1268

perror("sigaction");

1269

exitcode = EX_OSERR;

1270

goto end;

1271

}

1272

}

1273

1274

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

1275

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

1276

if_index = (AvahiIfIndex) if_nametoindex(interface);

1277

if(if_index == 0){

1278

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

1279

exitcode = EX_UNAVAILABLE;

1280

goto end;

1281

}

1282

1283

if(quit_now){

1284

goto end;

1285

}

1286

1287

/* Re-raise priviliges */

1288

errno = 0;

1289

ret = seteuid(0);

1290

if(ret == -1){

1291

perror("seteuid");

1292

}

1293

1294

#ifdef __linux__

1295

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1296

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

1297

ret = klogctl(8, NULL, 5);

1298

bool restore_loglevel = true;

1299

if(ret == -1){

1300

restore_loglevel = false;

1301

perror("klogctl");

1302

}

1303

#endif /* __linux__ */

1304

1305

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1306

if(sd < 0){

1307

perror("socket");

1308

exitcode = EX_OSERR;

1309

#ifdef __linux__

1310

if(restore_loglevel){

1311

ret = klogctl(7, NULL, 0);

1312

if(ret == -1){

1313

perror("klogctl");

1314

}

1315

}

1316

#endif /* __linux__ */

1317

/* Lower privileges */

1318

errno = 0;

1319

ret = seteuid(uid);

1320

if(ret == -1){

1321

perror("seteuid");

1322

}

1323

goto end;

1324

}

1325

strcpy(network.ifr_name, interface);

1326

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

1327

if(ret == -1){

1328

perror("ioctl SIOCGIFFLAGS");

1329

#ifdef __linux__

1330

if(restore_loglevel){

1331

ret = klogctl(7, NULL, 0);

1332

if(ret == -1){

1333

perror("klogctl");

1334

}

1335

}

1336

#endif /* __linux__ */

1337

exitcode = EX_OSERR;

1338

/* Lower privileges */

1339

errno = 0;

1340

ret = seteuid(uid);

1341

if(ret == -1){

1342

perror("seteuid");

1343

}

1344

goto end;

1345

}

1346

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

1347

network.ifr_flags |= IFF_UP;

1348

take_down_interface = true;

1349

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

1350

if(ret == -1){

1351

take_down_interface = false;

1352

perror("ioctl SIOCSIFFLAGS");

1353

exitcode = EX_OSERR;

1354

#ifdef __linux__

1355

if(restore_loglevel){

1356

ret = klogctl(7, NULL, 0);

1357

if(ret == -1){

1358

perror("klogctl");

2827

perror_plus("sigaction");

2828

exitcode = EX_OSERR;

2829

goto end;

2830

}

2831

}

2832

2833

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

2834

if(mc.interfaces == NULL){

2835

struct dirent **direntries = NULL;

2836

/* Look for any good interfaces */

2837

ret = scandir(sys_class_net, &direntries, good_interface,

2838

alphasort);

2839

if(ret >= 1){

2840

/* Add all found interfaces to interfaces list */

2841

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

2842

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

2843

direntries[i]->d_name);

2844

if(ret_errno != 0){

2845

errno = ret_errno;

2846

perror_plus("argz_add");

2847

free(direntries[i]);

2848

continue;

2849

}

2850

if(debug){

2851

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

2852

direntries[i]->d_name);

2853

}

2854

free(direntries[i]);

2855

}

2856

free(direntries);

2857

} else {

2858

if(ret == 0){

2859

free(direntries);

2860

}

2861

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

2862

exitcode = EXIT_FAILURE;

2863

goto end;

2864

}

2865

}

2866

2867

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

2868

{

2869

char *interface = NULL;

2870

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

2871

interface))){

2872

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

2873

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

2874

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

2875

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

2876

interface);

2877

interface = NULL;

2878

while((interface = argz_next(mc.interfaces,

2879

mc.interfaces_size, interface))){

2880

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

2881

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

2882

interface);

2883

interface = NULL;

1359

2884

}

1360

2885

}

1361

#endif /* __linux__ */

1362

/* Lower privileges */

1363

errno = 0;

1364

ret = seteuid(uid);

1365

if(ret == -1){

1366

perror("seteuid");

1367

}

1368

goto end;

1369

}

1370

}

1371

/* sleep checking until interface is running */

1372

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

1373

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

1374

if(ret == -1){

1375

perror("ioctl SIOCGIFFLAGS");

1376

} else if(network.ifr_flags & IFF_RUNNING){

1377

2886

break;

1378

2887

}

1379

struct timespec sleeptime = { .tv_nsec = 250000000 };

1380

ret = nanosleep(&sleeptime, NULL);

1381

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

1382

perror("nanosleep");

1383

}

1384

}

1385

if(not take_down_interface){

1386

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

1387

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

1388

if(ret == -1){

1389

perror("close");

1390

}

1391

}

1392

#ifdef __linux__

1393

if(restore_loglevel){

1394

/* Restores kernel loglevel to default */

1395

ret = klogctl(7, NULL, 0);

1396

if(ret == -1){

1397

perror("klogctl");

1398

}

1399

}

1400

#endif /* __linux__ */

1401

/* Lower privileges */

1402

errno = 0;

1403

if(take_down_interface){

1404

/* Lower privileges */

1405

ret = seteuid(uid);

1406

if(ret == -1){

1407

perror("seteuid");

1408

}

1409

} else {

1410

/* Lower privileges permanently */

1411

ret = setuid(uid);

1412

if(ret == -1){

1413

perror("setuid");

1414

}

1415

}

2888

bool interface_was_up = interface_is_up(interface);

2889

errno = bring_up_interface(interface, delay);

2890

if(not interface_was_up){

2891

if(errno != 0){

2892

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

2893

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

2894

} else {

2895

errno = argz_add(&interfaces_to_take_down,

2896

&interfaces_to_take_down_size,

2897

interface);

2898

if(errno != 0){

2899

perror_plus("argz_add");

2900

}

2901

}

2902

}

2903

}

2904

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

2905

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

2906

}

2907

}

2908

2909

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

2910

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

2911

if(debug){

2912

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

2913

mc.interfaces);

2914

}

2915

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

1416

2916

}

1417

2917

1418

2918

if(quit_now){

1419

2919

goto end;

1420

2920

}

1421

2921

1422

ret = init_gnutls_global(pubkey, seckey);

2922

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

1423

2923

if(ret == -1){

1424

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

2924

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

1425

2925

exitcode = EX_UNAVAILABLE;

1426

2926

goto end;

1427

2927

} else {

1432

2932

goto end;

1433

2933

}

1434

2934

1435

tempdir_created = true;

1436

if(mkdtemp(tempdir) == NULL){

1437

tempdir_created = false;

1438

perror("mkdtemp");

2935

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

2936

tempdir = mkdtemp(run_tempdir);

2937

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

2938

if(debug){

2939

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

2940

run_tempdir, old_tempdir);

2941

}

2942

tempdir = mkdtemp(old_tempdir);

2943

}

2944

if(tempdir == NULL){

2945

perror_plus("mkdtemp");

1439

2946

goto end;

1440

2947

}

1441

2948

1443

2950

goto end;

1444

2951

}

1445

2952

1446

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

1447

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

2953

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

2954

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

1448

2955

exitcode = EX_UNAVAILABLE;

1449

2956

goto end;

1450

2957

} else {

1459

2966

/* Connect directly, do not use Zeroconf */

1460

2967

/* (Mainly meant for debugging) */

1461

2968

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

2969

1462

2970

if(address == NULL){

1463

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

2971

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

1464

2972

exitcode = EX_USAGE;

1465

2973

goto end;

1466

2974

}

1469

2977

goto end;

1470

2978

}

1471

2979

1472

uint16_t port;

2980

in_port_t port;

1473

2981

errno = 0;

1474

2982

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

1475

2983

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

1476

or tmpmax != (uint16_t)tmpmax){

1477

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

2984

or tmpmax != (in_port_t)tmpmax){

2985

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

1478

2986

exitcode = EX_USAGE;

1479

2987

goto end;

1480

2988

}

1481

2989

1482

2990

if(quit_now){

1483

2991

goto end;

1484

2992

}

1485

2993

1486

port = (uint16_t)tmpmax;

2994

port = (in_port_t)tmpmax;

1487

2995

*address = '\0';

1488

address = connect_to;

1489

2996

/* Colon in address indicates IPv6 */

1490

2997

int af;

1491

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

2998

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

1492

2999

af = AF_INET6;

3000

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

3001

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

3002

{

3003

connect_to++;

3004

address[-1] = '\0';

3005

}

1493

3006

} else {

1494

3007

af = AF_INET;

1495

3008

}

3009

address = connect_to;

1496

3010

1497

3011

if(quit_now){

1498

3012

goto end;

1499

3013

}

1500

3014

1501

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

1502

if(ret < 0){

1503

switch(errno){

1504

case ENETUNREACH:

1505

case EHOSTDOWN:

1506

case EHOSTUNREACH:

1507

exitcode = EX_NOHOST;

1508

break;

1509

case EINVAL:

1510

exitcode = EX_USAGE;

1511

break;

1512

case EIO:

1513

exitcode = EX_IOERR;

1514

break;

1515

case EPROTO:

1516

exitcode = EX_PROTOCOL;

1517

break;

1518

default:

1519

exitcode = EX_OSERR;

1520

break;

1521

}

1522

} else {

3015

while(not quit_now){

3016

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

3017

&mc);

3018

if(quit_now or ret == 0){

3019

break;

3020

}

3021

if(debug){

3022

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

3023

(int)retry_interval);

3024

}

3025

sleep((unsigned int)retry_interval);

3026

}

3027

3028

if(not quit_now){

1523

3029

exitcode = EXIT_SUCCESS;

1524

3030

}

3031

1525

3032

goto end;

1526

3033

}

1527

3034

1539

3046

config.publish_domain = 0;

1540

3047

1541

3048

/* Allocate a new server */

1542

mc.server = avahi_server_new(avahi_simple_poll_get

1543

(mc.simple_poll), &config, NULL,

1544

NULL, &error);

3049

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3050

&config, NULL, NULL, &ret);

1545

3051

1546

3052

/* Free the Avahi configuration data */

1547

3053

avahi_server_config_free(&config);

1549

3055

1550

3056

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

1551

3057

if(mc.server == NULL){

1552

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

1553

avahi_strerror(error));

3058

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

3059

avahi_strerror(ret));

1554

3060

exitcode = EX_UNAVAILABLE;

1555

3061

goto end;

1556

3062

}

1562

3068

/* Create the Avahi service browser */

1563

3069

sb = avahi_s_service_browser_new(mc.server, if_index,

1564

3070

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1565

NULL, 0, browse_callback, NULL);

3071

NULL, 0, browse_callback,

3072

(void *)&mc);

1566

3073

if(sb == NULL){

1567

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

1568

avahi_strerror(avahi_server_errno(mc.server)));

3074

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

3075

avahi_strerror(avahi_server_errno(mc.server)));

1569

3076

exitcode = EX_UNAVAILABLE;

1570

3077

goto end;

1571

3078

}

1577

3084

/* Run the main loop */

1578

3085

1579

3086

if(debug){

1580

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

3087

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

1581

3088

}

1582

3089

1583

avahi_simple_poll_loop(mc.simple_poll);

3090

ret = avahi_loop_with_timeout(simple_poll,

3091

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

3092

if(debug){

3093

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

3094

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

3095

}

1584

3096

1585

3097

end:

1586

3098

1587

3099

if(debug){

1588

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

3100

if(signal_received){

3101

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

3102

argv[0], signal_received,

3103

strsignal(signal_received));

3104

} else {

3105

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

3106

}

1589

3107

}

1590

3108

1591

3109

/* Cleanup things */

3110

free(mc.interfaces);

3111

1592

3112

if(sb != NULL)

1593

3113

avahi_s_service_browser_free(sb);

1594

3114

1595

3115

if(mc.server != NULL)

1596

3116

avahi_server_free(mc.server);

1597

3117

1598

if(mc.simple_poll != NULL)

1599

avahi_simple_poll_free(mc.simple_poll);

3118

if(simple_poll != NULL)

3119

avahi_simple_poll_free(simple_poll);

1600

3120

1601

3121

if(gnutls_initialized){

1602

3122

gnutls_certificate_free_credentials(mc.cred);

1603

gnutls_global_deinit();

1604

3123

gnutls_dh_params_deinit(mc.dh_params);

1605

3124

}

1606

3125

1608

3127

gpgme_release(mc.ctx);

1609

3128

}

1610

3129

1611

/* Take down the network interface */

1612

if(take_down_interface){

1613

/* Re-raise priviliges */

1614

errno = 0;

1615

ret = seteuid(0);

1616

if(ret == -1){

1617

perror("seteuid");

1618

}

1619

if(geteuid() == 0){

1620

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

1621

if(ret == -1){

1622

perror("ioctl SIOCGIFFLAGS");

1623

} else if(network.ifr_flags & IFF_UP) {

1624

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

1625

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

1626

if(ret == -1){

1627

perror("ioctl SIOCSIFFLAGS");

1628

}

1629

}

1630

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

1631

if(ret == -1){

1632

perror("close");

1633

}

1634

/* Lower privileges permanently */

1635

errno = 0;

1636

ret = setuid(uid);

1637

if(ret == -1){

1638

perror("setuid");

1639

}

1640

}

1641

}

1642

1643

/* Removes the temp directory used by GPGME */

1644

if(tempdir_created){

1645

DIR *d;

1646

struct dirent *direntry;

1647

d = opendir(tempdir);

1648

if(d == NULL){

1649

if(errno != ENOENT){

1650

perror("opendir");

1651

}

1652

} else {

1653

while(true){

1654

direntry = readdir(d);

1655

if(direntry == NULL){

1656

break;

1657

}

1658

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

1659

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

1660

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

1661

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

1662

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

1663

continue;

1664

}

1665

char *fullname = NULL;

1666

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

1667

direntry->d_name);

1668

if(ret < 0){

1669

perror("asprintf");

1670

continue;

1671

}

1672

ret = remove(fullname);

1673

if(ret == -1){

1674

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

1675

strerror(errno));

1676

}

1677

free(fullname);

1678

}

1679

closedir(d);

1680

}

1681

ret = rmdir(tempdir);

1682

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

1683

perror("rmdir");

1684

}

3130

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

3131

has seen */

3132

if(mc.current_server != NULL){

3133

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

3134

while(mc.current_server != NULL){

3135

server *next = mc.current_server->next;

3136

#ifdef __GNUC__

3137

#pragma GCC diagnostic push

3138

#pragma GCC diagnostic ignored "-Wcast-qual"

3139

#endif

3140

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

3141

#ifdef __GNUC__

3142

#pragma GCC diagnostic pop

3143

#endif

3144

free(mc.current_server);

3145

mc.current_server = next;

3146

}

3147

}

3148

3149

/* Re-raise privileges */

3150

{

3151

ret = raise_privileges();

3152

if(ret != 0){

3153

errno = ret;

3154

perror_plus("Failed to raise privileges");

3155

} else {

3156

3157

/* Run network hooks */

3158

run_network_hooks("stop", interfaces_hooks != NULL ?

3159

interfaces_hooks : "", delay);

3160

3161

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

3162

{

3163

char *interface = NULL;

3164

while((interface = argz_next(interfaces_to_take_down,

3165

interfaces_to_take_down_size,

3166

interface))){

3167

ret = take_down_interface(interface);

3168

if(ret != 0){

3169

errno = ret;

3170

perror_plus("Failed to take down interface");

3171

}

3172

}

3173

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

3174

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

3175

" down\n");

3176

}

3177

}

3178

}

3179

3180

ret = lower_privileges_permanently();

3181

if(ret != 0){

3182

errno = ret;

3183

perror_plus("Failed to lower privileges permanently");

3184

}

3185

}

3186

3187

free(interfaces_to_take_down);

3188

free(interfaces_hooks);

3189

3190

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

3191

uintmax_t level){

3192

struct dirent **direntries = NULL;

3193

int dret;

3194

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

3195

O_RDONLY

3196

| O_NOFOLLOW

3197

| O_DIRECTORY

3198

| O_PATH));

3199

if(dir_fd == -1){

3200

perror_plus("open");

3201

return;

3202

}

3203

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

3204

notdotentries, alphasort);

3205

if(numentries >= 0){

3206

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

3207

if(debug){

3208

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

3209

dirname, direntries[i]->d_name);

3210

}

3211

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

3212

if(dret == -1){

3213

if(errno == EISDIR){

3214

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

3215

AT_REMOVEDIR);

3216

}

3217

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

3218

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

3219

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

3220

/* Recurse only in this special case */

3221

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

3222

dret = 0;

3223

}

3224

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

3225

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

3226

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

3227

}

3228

}

3229

free(direntries[i]);

3230

}

3231

3232

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

3233

free(direntries);

3234

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3235

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

3236

perror_plus("rmdir");

3237

}

3238

} else {

3239

perror_plus("scandirat");

3240

}

3241

close(dir_fd);

3242

}

3243

3244

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

3245

if(tempdir != NULL){

3246

clean_dir_at(-1, tempdir, 0);

1685

3247

}

1686

3248

1687

3249

if(quit_now){

1691

3253

&old_sigterm_action,

1692

3254

NULL));

1693

3255

if(ret == -1){

1694

perror("sigaction");

3256

perror_plus("sigaction");

1695

3257

}

1696

3258

do {

1697

3259

ret = raise(signal_received);

1698

3260

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

1699

3261

if(ret != 0){

1700

perror("raise");

3262

perror_plus("raise");

1701

3263

abort();

1702

3264

}

1703

3265

TEMP_FAILURE_RETRY(pause());