/mandos/release : revision 237.7.137

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

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*

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* Everything else is

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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*

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

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

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

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

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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stdout, ferror(), remove() */

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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> /* strcmp(), strlen(), strerror(),

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asprintf(), strncpy(), strsignal()

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*/

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

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

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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

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

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program_invocation_short_name */

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

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

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*/

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

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

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

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unlinkat() */

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

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

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

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

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

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#if GNUTLS_VERSION_NUMBER < 0x030600

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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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#elif GNUTLS_VERSION_NUMBER >= 0x030606

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#include <gnutls/x509.h> /* gnutls_pkcs_encrypt_flags_t,

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GNUTLS_PKCS_PLAIN,

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GNUTLS_PKCS_NULL_PASSWORD */

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#endif

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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 TLS_PRIVKEY "tls-privkey.pem"

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#define TLS_PUBKEY "tls-pubkey.pem"

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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 sys_class_net[] = "/sys/class/net";

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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161

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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perror(print_text);

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}

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

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

217

__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){

220

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

232

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return buffer_capacity;

233

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}

234

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235

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

236

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

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int af){

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int ret;

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

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if(new_server == NULL){

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.af = af };

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if(new_server->ip == NULL){

250

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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));

255

if(ret == -1){

256

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"

260

#endif

261

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

262

#ifdef __GNUC__

263

#pragma GCC diagnostic pop

264

#endif

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free(new_server);

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return false;

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}

268

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/* Special case of first server */

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if(*current_server == NULL){

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if (mc.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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mc.current_server = new_server;

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

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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->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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mc.current_server->prev = new_server;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return false;

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}

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return true;

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}

282

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

286

int old_errno = errno;

287

int ret = 0;

288

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

289

ret = errno;

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}

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errno = old_errno;

292

return ret;

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}

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

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

298

int old_errno = errno;

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int ret = raise_privileges();

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if(ret != 0){

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errno = old_errno;

302

return ret;

303

}

304

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

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ret = errno;

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}

307

errno = old_errno;

308

return ret;

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}

310

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

312

__attribute__((warn_unused_result))

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int lower_privileges(void){

314

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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}

319

errno = old_errno;

320

return ret;

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}

322

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/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

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int old_errno = errno;

327

int ret = 0;

328

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

329

ret = errno;

330

}

331

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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__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,

342

mandos_context *mc){

247

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

248

const char *tempdir){

343

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gpgme_error_t rc;

344

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gpgme_engine_info_t engine_info;

345

251

252

346

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/*

347

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

348

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*/

349

bool import_key(const char * const filename){

256

bool import_key(const char *filename){

350

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int ret;

351

258

int fd;

352

259

gpgme_data_t pgp_data;

357

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return false;

358

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}

359

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

361

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

362

do {

363

{

364

time_t currtime = time(NULL);

365

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

366

struct tm tm;

367

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

368

perror_plus("gmtime_r");

369

break;

370

}

371

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

372

break;

373

}

374

if(debug){

375

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

376

}

377

} else {

378

if(debug){

379

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

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

time_t keytime = keystat.st_mtim.tv_sec;

400

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

401

perror_plus("stime");

402

}

403

ret = lower_privileges();

404

if(ret != 0){

405

errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

410

267

rc = gpgme_data_new_from_fd(&pgp_data, fd);

411

268

if(rc != GPG_ERR_NO_ERROR){

412

269

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

414

271

return false;

415

272

}

416

273

417

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

274

rc = gpgme_op_import(mc.ctx, pgp_data);

418

275

if(rc != GPG_ERR_NO_ERROR){

419

276

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

420

277

gpgme_strsource(rc), gpgme_strerror(rc));

421

278

return false;

422

279

}

423

{

424

gpgme_import_result_t import_result

425

= gpgme_op_import_result(mc->ctx);

426

if((import_result->imported < 1

427

or import_result->not_imported > 0)

428

and import_result->unchanged == 0){

429

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

430

fprintf_plus(stderr,

431

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

432

import_result->considered);

433

fprintf_plus(stderr,

434

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

435

import_result->no_user_id);

436

fprintf_plus(stderr,

437

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

438

import_result->imported);

439

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

440

import_result->imported_rsa);

441

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

442

import_result->unchanged);

443

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

444

import_result->new_user_ids);

445

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

446

import_result->new_sub_keys);

447

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

448

import_result->new_signatures);

449

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

450

import_result->new_revocations);

451

fprintf_plus(stderr,

452

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

453

import_result->secret_read);

454

fprintf_plus(stderr,

455

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

456

import_result->secret_imported);

457

fprintf_plus(stderr,

458

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

459

import_result->secret_unchanged);

460

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

461

import_result->not_imported);

462

for(gpgme_import_status_t import_status

463

= import_result->imports;

464

import_status != NULL;

465

import_status = import_status->next){

466

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

467

import_status->fpr);

468

if(import_status->result != GPG_ERR_NO_ERROR){

469

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

470

gpgme_strsource(import_status->result),

471

gpgme_strerror(import_status->result));

472

}

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_NEW

476

? "The key was new.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_UID

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SIG

484

? "The key contained new signatures.\n"

485

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

486

fprintf_plus(stderr,

487

import_status->status & GPGME_IMPORT_SUBKEY

488

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

489

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

490

fprintf_plus(stderr,

491

import_status->status & GPGME_IMPORT_SECRET

492

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

493

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

494

}

495

return false;

496

}

497

}

498

280

499

ret = close(fd);

281

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

500

282

if(ret == -1){

501

283

perror_plus("close");

502

284

}

539

321

}

540

322

541

323

/* Create new GPGME "context" */

542

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

324

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

543

325

if(rc != GPG_ERR_NO_ERROR){

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

326

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

327

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

328

gpgme_strerror(rc));

546

329

return false;

547

330

}

548

331

557

340

* Decrypt OpenPGP data.

558

341

* Returns -1 on error

559

342

*/

560

__attribute__((nonnull, warn_unused_result))

561

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

562

344

size_t crypto_size,

563

char **plaintext,

564

mandos_context *mc){

345

char **plaintext){

565

346

gpgme_data_t dh_crypto, dh_plain;

566

347

gpgme_error_t rc;

567

348

ssize_t ret;

584

365

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

585

366

rc = gpgme_data_new(&dh_plain);

586

367

if(rc != GPG_ERR_NO_ERROR){

587

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

368

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

369

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

588

370

gpgme_strsource(rc), gpgme_strerror(rc));

589

371

gpgme_data_release(dh_crypto);

590

372

return -1;

592

374

593

375

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

594

376

data buffer */

595

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

377

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

596

378

if(rc != GPG_ERR_NO_ERROR){

597

379

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

598

380

gpgme_strsource(rc), gpgme_strerror(rc));

599

381

plaintext_length = -1;

600

382

if(debug){

601

383

gpgme_decrypt_result_t result;

602

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

603

385

if(result == NULL){

604

386

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

605

387

} else {

606

if(result->unsupported_algorithm != NULL) {

607

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

608

result->unsupported_algorithm);

609

}

610

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

611

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

388

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

389

result->unsupported_algorithm);

390

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

391

result->wrong_key_usage);

612

392

if(result->file_name != NULL){

613

393

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

614

394

}

615

616

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

617

r = r->next){

395

gpgme_recipient_t recipient;

396

recipient = result->recipients;

397

while(recipient != NULL){

618

398

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

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

621

402

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

622

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

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

405

recipient = recipient->next;

623

406

}

624

407

}

625

408

}

681

464

return plaintext_length;

682

465

}

683

466

684

__attribute__((warn_unused_result, const))

685

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

686

if(str == NULL)

687

return "(unknown)";

688

return str;

689

}

690

691

__attribute__((warn_unused_result))

692

static const char *safer_gnutls_strerror(int value){

693

const char *ret = gnutls_strerror(value);

694

return safe_string(ret);

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

470

if(ret == NULL)

471

ret = "(unknown)";

472

return ret;

695

473

}

696

474

697

475

/* GnuTLS log function callback */

698

__attribute__((nonnull))

699

476

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

700

477

const char* string){

701

478

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

702

479

}

703

480

704

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

705

481

static int init_gnutls_global(const char *pubkeyfilename,

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

mandos_context *mc){

482

const char *seckeyfilename){

709

483

int ret;

710

484

711

485

if(debug){

712

486

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

713

487

}

714

488

489

ret = gnutls_global_init();

490

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

493

return -1;

494

}

495

715

496

if(debug){

716

497

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

717

498

* - GnuTLS manual

721

502

}

722

503

723

504

/* OpenPGP credentials */

724

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

725

506

if(ret != GNUTLS_E_SUCCESS){

726

507

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

727

508

safer_gnutls_strerror(ret));

509

gnutls_global_deinit();

728

510

return -1;

729

511

}

730

512

731

513

if(debug){

732

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

733

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

514

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

515

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

734

516

pubkeyfilename,

735

517

seckeyfilename);

736

518

}

737

519

738

#if GNUTLS_VERSION_NUMBER >= 0x030606

739

ret = gnutls_certificate_set_rawpk_key_file

740

(mc->cred, pubkeyfilename, seckeyfilename,

741

GNUTLS_X509_FMT_PEM, /* format */

742

NULL, /* pass */

743

/* key_usage */

744

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

745

NULL, /* names */

746

0, /* names_length */

747

/* privkey_flags */

748

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

749

0); /* pkcs11_flags */

750

#elif GNUTLS_VERSION_NUMBER < 0x030600

751

520

ret = gnutls_certificate_set_openpgp_key_file

752

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

753

522

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

756

#endif

757

523

if(ret != GNUTLS_E_SUCCESS){

758

524

fprintf_plus(stderr,

759

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

525

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

760

526

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

761

527

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

762

528

safer_gnutls_strerror(ret));

764

530

}

765

531

766

532

/* GnuTLS server initialization */

767

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

768

534

if(ret != GNUTLS_E_SUCCESS){

769

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

770

536

" initialization: %s\n",

771

537

safer_gnutls_strerror(ret));

772

538

goto globalfail;

773

539

}

774

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

775

if(dhparamsfilename != NULL){

776

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

777

do {

778

int dhpfile = open(dhparamsfilename, O_RDONLY);

779

if(dhpfile == -1){

780

perror_plus("open");

781

dhparamsfilename = NULL;

782

break;

783

}

784

size_t params_capacity = 0;

785

while(true){

786

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

787

(size_t)params.size,

788

(size_t)params_capacity);

789

if(params_capacity == 0){

790

perror_plus("incbuffer");

791

free(params.data);

792

params.data = NULL;

793

dhparamsfilename = NULL;

794

break;

795

}

796

ssize_t bytes_read = read(dhpfile,

797

params.data + params.size,

798

BUFFER_SIZE);

799

/* EOF */

800

if(bytes_read == 0){

801

break;

802

}

803

/* check bytes_read for failure */

804

if(bytes_read < 0){

805

perror_plus("read");

806

free(params.data);

807

params.data = NULL;

808

dhparamsfilename = NULL;

809

break;

810

}

811

params.size += (unsigned int)bytes_read;

812

}

813

ret = close(dhpfile);

814

if(ret == -1){

815

perror_plus("close");

816

}

817

if(params.data == NULL){

818

dhparamsfilename = NULL;

819

}

820

if(dhparamsfilename == NULL){

821

break;

822

}

823

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

824

GNUTLS_X509_FMT_PEM);

825

if(ret != GNUTLS_E_SUCCESS){

826

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

827

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

828

safer_gnutls_strerror(ret));

829

dhparamsfilename = NULL;

830

}

831

free(params.data);

832

} while(false);

833

}

834

if(dhparamsfilename == NULL){

835

if(mc->dh_bits == 0){

836

#if GNUTLS_VERSION_NUMBER < 0x030600

837

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

838

/* Try to read the private key file */

839

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

840

do {

841

int secfile = open(seckeyfilename, O_RDONLY);

842

if(secfile == -1){

843

perror_plus("open");

844

break;

845

}

846

size_t buffer_capacity = 0;

847

while(true){

848

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

849

(size_t)buffer.size,

850

(size_t)buffer_capacity);

851

if(buffer_capacity == 0){

852

perror_plus("incbuffer");

853

free(buffer.data);

854

buffer.data = NULL;

855

break;

856

}

857

ssize_t bytes_read = read(secfile,

858

buffer.data + buffer.size,

859

BUFFER_SIZE);

860

/* EOF */

861

if(bytes_read == 0){

862

break;

863

}

864

/* check bytes_read for failure */

865

if(bytes_read < 0){

866

perror_plus("read");

867

free(buffer.data);

868

buffer.data = NULL;

869

break;

870

}

871

buffer.size += (unsigned int)bytes_read;

872

}

873

close(secfile);

874

} while(false);

875

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

876

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

877

if(buffer.data != NULL){

878

{

879

gnutls_openpgp_privkey_t privkey = NULL;

880

ret = gnutls_openpgp_privkey_init(&privkey);

881

if(ret != GNUTLS_E_SUCCESS){

882

fprintf_plus(stderr, "Error initializing OpenPGP key"

883

" structure: %s",

884

safer_gnutls_strerror(ret));

885

free(buffer.data);

886

buffer.data = NULL;

887

} else {

888

ret = gnutls_openpgp_privkey_import

889

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

890

if(ret != GNUTLS_E_SUCCESS){

891

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

892

safer_gnutls_strerror(ret));

893

privkey = NULL;

894

}

895

free(buffer.data);

896

buffer.data = NULL;

897

if(privkey != NULL){

898

/* Use private key to suggest an appropriate

899

sec_param */

900

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

901

gnutls_openpgp_privkey_deinit(privkey);

902

if(debug){

903

fprintf_plus(stderr, "This OpenPGP key implies using"

904

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

905

safe_string(gnutls_sec_param_get_name

906

(sec_param)));

907

}

908

}

909

}

910

}

911

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

912

/* Err on the side of caution */

913

sec_param = GNUTLS_SEC_PARAM_ULTRA;

914

if(debug){

915

fprintf_plus(stderr, "Falling back to security parameter"

916

" \"%s\"\n",

917

safe_string(gnutls_sec_param_get_name

918

(sec_param)));

919

}

920

}

921

}

922

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

923

if(uret != 0){

924

mc->dh_bits = uret;

925

if(debug){

926

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

927

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

928

safe_string(gnutls_sec_param_get_name

929

(sec_param)),

930

mc->dh_bits);

931

}

932

} else {

933

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

934

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

935

safe_string(gnutls_sec_param_get_name

936

(sec_param)),

937

safer_gnutls_strerror(ret));

938

goto globalfail;

939

}

940

#endif

941

} else { /* dh_bits != 0 */

942

if(debug){

943

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

944

mc->dh_bits);

945

}

946

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

947

if(ret != GNUTLS_E_SUCCESS){

948

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

949

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

950

safer_gnutls_strerror(ret));

951

goto globalfail;

952

}

953

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

954

}

955

}

540

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

541

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

544

goto globalfail;

545

}

546

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

956

548

957

549

return 0;

958

550

959

551

globalfail:

960

552

961

gnutls_certificate_free_credentials(mc->cred);

962

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_certificate_free_credentials(mc.cred);

554

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

963

556

return -1;

964

557

}

965

558

966

__attribute__((nonnull, warn_unused_result))

967

static int init_gnutls_session(gnutls_session_t *session,

968

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

969

560

int ret;

970

561

/* GnuTLS session creation */

971

562

do {

972

ret = gnutls_init(session, (GNUTLS_SERVER

973

#if GNUTLS_VERSION_NUMBER >= 0x030506

974

| GNUTLS_NO_TICKETS

975

#endif

976

#if GNUTLS_VERSION_NUMBER >= 0x030606

977

| GNUTLS_ENABLE_RAWPK

978

#endif

979

));

563

ret = gnutls_init(session, GNUTLS_SERVER);

980

564

if(quit_now){

981

565

return -1;

982

566

}

990

574

{

991

575

const char *err;

992

576

do {

993

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

577

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

994

578

if(quit_now){

995

579

gnutls_deinit(*session);

996

580

return -1;

1007

591

1008

592

do {

1009

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1010

mc->cred);

594

mc.cred);

1011

595

if(quit_now){

1012

596

gnutls_deinit(*session);

1013

597

return -1;

1023

607

/* ignore client certificate if any. */

1024

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1025

609

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

611

1026

612

return 0;

1027

613

}

1028

614

1030

616

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

1031

617

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

1032

618

1033

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

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool add_delete_local_route(const bool add,

1036

const char *address,

1037

AvahiIfIndex if_index){

1038

int ret;

1039

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

1040

char add_arg[] = "add";

1041

char delete_arg[] = "delete";

1042

char debug_flag[] = "--debug";

1043

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1044

if(pluginhelperdir == NULL){

1045

if(debug){

1046

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1047

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

1048

}

1049

return false;

1050

}

1051

1052

char interface[IF_NAMESIZE];

1053

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

1054

perror_plus("if_indextoname");

1055

return false;

1056

}

1057

1058

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

1059

if(devnull == -1){

1060

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

1061

return false;

1062

}

1063

pid_t pid = fork();

1064

if(pid == 0){

1065

/* Child */

1066

/* Raise privileges */

1067

errno = raise_privileges_permanently();

1068

if(errno != 0){

1069

perror_plus("Failed to raise privileges");

1070

/* _exit(EX_NOPERM); */

1071

} else {

1072

/* Set group */

1073

errno = 0;

1074

ret = setgid(0);

1075

if(ret == -1){

1076

perror_plus("setgid");

1077

close(devnull);

1078

_exit(EX_NOPERM);

1079

}

1080

/* Reset supplementary groups */

1081

errno = 0;

1082

ret = setgroups(0, NULL);

1083

if(ret == -1){

1084

perror_plus("setgroups");

1085

close(devnull);

1086

_exit(EX_NOPERM);

1087

}

1088

}

1089

ret = dup2(devnull, STDIN_FILENO);

1090

if(ret == -1){

1091

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

1092

close(devnull);

1093

_exit(EX_OSERR);

1094

}

1095

ret = close(devnull);

1096

if(ret == -1){

1097

perror_plus("close");

1098

}

1099

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1100

if(ret == -1){

1101

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

1102

_exit(EX_OSERR);

1103

}

1104

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

1105

O_RDONLY

1106

| O_DIRECTORY

1107

| O_PATH

1108

| O_CLOEXEC));

1109

if(helperdir_fd == -1){

1110

perror_plus("open");

1111

_exit(EX_UNAVAILABLE);

1112

}

1113

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

1114

helper, O_RDONLY));

1115

if(helper_fd == -1){

1116

perror_plus("openat");

1117

close(helperdir_fd);

1118

_exit(EX_UNAVAILABLE);

1119

}

1120

close(helperdir_fd);

1121

#ifdef __GNUC__

1122

#pragma GCC diagnostic push

1123

#pragma GCC diagnostic ignored "-Wcast-qual"

1124

#endif

1125

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

1126

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

1127

interface, debug ? debug_flag : NULL, NULL },

1128

environ) == -1){

1129

#ifdef __GNUC__

1130

#pragma GCC diagnostic pop

1131

#endif

1132

perror_plus("fexecve");

1133

_exit(EXIT_FAILURE);

1134

}

1135

}

1136

if(pid == -1){

1137

perror_plus("fork");

1138

close(devnull);

1139

return false;

1140

}

1141

ret = close(devnull);

1142

if(ret == -1){

1143

perror_plus("close");

1144

}

1145

int status;

1146

pid_t pret = -1;

1147

errno = 0;

1148

do {

1149

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

1150

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

1151

int errno_raising = 0;

1152

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

1153

errno_raising = errno;

1154

perror_plus("Failed to raise privileges in order to"

1155

" kill helper program");

1156

}

1157

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

1158

perror_plus("kill");

1159

}

1160

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

1161

perror_plus("Failed to lower privileges after killing"

1162

" helper program");

1163

}

1164

return false;

1165

}

1166

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

1167

if(pret == -1){

1168

perror_plus("waitpid");

1169

return false;

1170

}

1171

if(WIFEXITED(status)){

1172

if(WEXITSTATUS(status) != 0){

1173

fprintf_plus(stderr, "Error: iprouteadddel exited"

1174

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

1175

return false;

1176

}

1177

return true;

1178

}

1179

if(WIFSIGNALED(status)){

1180

fprintf_plus(stderr, "Error: iprouteadddel died by"

1181

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

1182

return false;

1183

}

1184

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

1185

return false;

1186

}

1187

1188

__attribute__((nonnull, warn_unused_result))

1189

static bool add_local_route(const char *address,

1190

AvahiIfIndex if_index){

1191

if(debug){

1192

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

1193

}

1194

return add_delete_local_route(true, address, if_index);

1195

}

1196

1197

__attribute__((nonnull, warn_unused_result))

1198

static bool delete_local_route(const char *address,

1199

AvahiIfIndex if_index){

1200

if(debug){

1201

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

1202

}

1203

return add_delete_local_route(false, address, if_index);

1204

}

1205

1206

619

/* Called when a Mandos server is found */

1207

__attribute__((nonnull, warn_unused_result))

1208

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

620

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

1209

621

AvahiIfIndex if_index,

1210

int af, mandos_context *mc){

622

int af){

1211

623

int ret, tcp_sd = -1;

1212

624

ssize_t sret;

1213

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

1214

629

char *buffer = NULL;

1215

630

char *decrypted_buffer = NULL;

1216

631

size_t buffer_length = 0;

1219

634

int retval = -1;

1220

635

gnutls_session_t session;

1221

636

int pf; /* Protocol family */

1222

bool route_added = false;

1223

637

1224

638

errno = 0;

1225

639

1241

655

return -1;

1242

656

}

1243

657

1244

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

1245

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

1246

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

1247

bool match = false;

1248

{

1249

char *interface = NULL;

1250

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

1251

mc->interfaces_size,

1252

interface))){

1253

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

1254

match = true;

1255

break;

1256

}

1257

}

1258

}

1259

if(not match){

1260

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

1261

connect to the server */

1262

if(debug){

1263

char interface[IF_NAMESIZE];

1264

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

1265

perror_plus("if_indextoname");

1266

} else {

1267

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

1268

" \"%s\"\n",

1269

if_indextoname((unsigned int)if_index,

1270

interface));

1271

}

1272

}

1273

return -1;

1274

}

1275

}

1276

1277

ret = init_gnutls_session(&session, mc);

658

ret = init_gnutls_session(&session);

1278

659

if(ret != 0){

1279

660

return -1;

1280

661

}

1281

662

1282

663

if(debug){

1283

664

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

1284

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

665

PRIu16 "\n", ip, port);

1285

666

}

1286

667

1287

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

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

1288

669

if(tcp_sd < 0){

1289

670

int e = errno;

1290

671

perror_plus("socket");

1297

678

goto mandos_end;

1298

679

}

1299

680

681

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

1300

682

if(af == AF_INET6){

1301

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

1302

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

1303

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

683

to.in6.sin6_family = (sa_family_t)af;

684

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

1304

685

} else { /* IPv4 */

1305

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

1306

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

1307

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

686

to.in.sin_family = (sa_family_t)af;

687

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

1308

688

}

1309

689

if(ret < 0 ){

1310

690

int e = errno;

1319

699

goto mandos_end;

1320

700

}

1321

701

if(af == AF_INET6){

1322

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

1323

if(IN6_IS_ADDR_LINKLOCAL

1324

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

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

1325

709

if(if_index == AVAHI_IF_UNSPEC){

1326

710

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

1327

711

" incomplete without a network interface\n");

1329

713

goto mandos_end;

1330

714

}

1331

715

/* Set the network interface number as scope */

1332

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

1333

717

}

1334

718

} else {

1335

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

1336

722

}

1337

723

1338

724

if(quit_now){

1346

732

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

1347

733

perror_plus("if_indextoname");

1348

734

} else {

1349

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

1350

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

735

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

736

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

1351

737

}

1352

738

} else {

1353

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

1354

ip, (uintmax_t)port);

739

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

740

ip, port);

1355

741

}

1356

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1357

743

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1358

if(af == AF_INET6){

1359

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

1360

sizeof(struct sockaddr_in6),

1361

addrstr, sizeof(addrstr), NULL, 0,

1362

NI_NUMERICHOST);

1363

} else {

1364

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

1365

sizeof(struct sockaddr_in),

1366

addrstr, sizeof(addrstr), NULL, 0,

1367

NI_NUMERICHOST);

1368

}

1369

if(ret == EAI_SYSTEM){

1370

perror_plus("getnameinfo");

1371

} else if(ret != 0) {

1372

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

1373

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

1374

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

1375

}

1376

}

1377

1378

if(quit_now){

1379

errno = EINTR;

1380

goto mandos_end;

1381

}

1382

1383

while(true){

1384

if(af == AF_INET6){

1385

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

1386

sizeof(struct sockaddr_in6));

1387

} else {

1388

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

1389

sizeof(struct sockaddr_in));

1390

}

1391

if(ret < 0){

1392

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

1393

and if_index != AVAHI_IF_UNSPEC

1394

and connect_to == NULL

1395

and not route_added and

1396

((af == AF_INET6 and not

1397

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1398

&to)->sin6_addr)))

1399

or (af == AF_INET and

1400

/* Not a a IPv4LL address */

1401

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

1402

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

1403

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

1404

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

1405

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

1406

connect to a Mandos server announced by Avahi on a server

1407

host with a global address. Work around this by retrying

1408

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

1409

1410

Avahi bug reference:

1411

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

1412

https://bugs.debian.org/587961

1413

*/

1414

if(debug){

1415

fprintf_plus(stderr, "Mandos server unreachable, trying"

1416

" direct route\n");

1417

}

1418

int e = errno;

1419

route_added = add_local_route(ip, if_index);

1420

if(route_added){

1421

continue;

1422

}

1423

errno = e;

1424

}

1425

if(errno != ECONNREFUSED or debug){

1426

int e = errno;

1427

perror_plus("connect");

1428

errno = e;

1429

}

1430

goto mandos_end;

1431

}

1432

1433

if(quit_now){

1434

errno = EINTR;

1435

goto mandos_end;

1436

}

1437

break;

744

const char *pcret;

745

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

748

} else {

749

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

750

sizeof(addrstr));

751

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

758

}

759

}

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

if(af == AF_INET6){

767

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

768

} else {

769

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

770

}

771

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

1438

783

}

1439

784

1440

785

const char *out = mandos_protocol_version;

1591

936

if(buffer_length > 0){

1592

937

ssize_t decrypted_buffer_size;

1593

938

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1594

&decrypted_buffer, mc);

939

&decrypted_buffer);

1595

940

if(decrypted_buffer_size >= 0){

1596

941

1597

clearerr(stdout);

1598

942

written = 0;

1599

943

while(written < (size_t) decrypted_buffer_size){

1600

944

if(quit_now){

1616

960

}

1617

961

written += (size_t)ret;

1618

962

}

1619

ret = fflush(stdout);

1620

if(ret != 0){

1621

int e = errno;

1622

if(debug){

1623

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

1624

strerror(errno));

1625

}

1626

errno = e;

1627

goto mandos_end;

1628

}

1629

963

retval = 0;

1630

964

}

1631

965

}

1634

968

1635

969

mandos_end:

1636

970

{

1637

if(route_added){

1638

if(not delete_local_route(ip, if_index)){

1639

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

1640

" interface %d", ip, if_index);

1641

}

1642

}

1643

971

int e = errno;

1644

972

free(decrypted_buffer);

1645

973

free(buffer);

1646

974

if(tcp_sd >= 0){

1647

ret = close(tcp_sd);

975

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

1648

976

}

1649

977

if(ret == -1){

1650

978

if(e == 0){

1675

1003

AVAHI_GCC_UNUSED AvahiStringList *txt,

1676

1004

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1677

1005

flags,

1678

void *mc){

1679

if(r == NULL){

1680

return;

1681

}

1006

AVAHI_GCC_UNUSED void* userdata){

1007

assert(r);

1682

1008

1683

1009

/* Called whenever a service has been resolved successfully or

1684

1010

timed out */

1685

1011

1686

1012

if(quit_now){

1687

avahi_s_service_resolver_free(r);

1688

1013

return;

1689

1014

}

1690

1015

1694

1019

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

1695

1020

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

1696

1021

domain,

1697

avahi_strerror(avahi_server_errno

1698

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

1022

avahi_strerror(avahi_server_errno(mc.server)));

1699

1023

break;

1700

1024

1701

1025

case AVAHI_RESOLVER_FOUND:

1707

1031

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

1708

1032

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

1709

1033

}

1710

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

1711

interface,

1712

avahi_proto_to_af(proto),

1713

mc);

1034

int ret = start_mandos_communication(ip, port, interface,

1035

avahi_proto_to_af(proto));

1714

1036

if(ret == 0){

1715

avahi_simple_poll_quit(simple_poll);

1037

avahi_simple_poll_quit(mc.simple_poll);

1716

1038

} else {

1717

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

1718

avahi_proto_to_af(proto),

1719

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

1039

if(not add_server(ip, port, interface,

1040

avahi_proto_to_af(proto))){

1720

1041

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

1721

1042

" list\n", name);

1722

1043

}

1735

1056

const char *domain,

1736

1057

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1737

1058

flags,

1738

void *mc){

1739

if(b == NULL){

1740

return;

1741

}

1059

AVAHI_GCC_UNUSED void* userdata){

1060

assert(b);

1742

1061

1743

1062

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

1744

1063

is removed from the LAN */

1752

1071

case AVAHI_BROWSER_FAILURE:

1753

1072

1754

1073

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

1755

avahi_strerror(avahi_server_errno

1756

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

1757

avahi_simple_poll_quit(simple_poll);

1074

avahi_strerror(avahi_server_errno(mc.server)));

1075

avahi_simple_poll_quit(mc.simple_poll);

1758

1076

return;

1759

1077

1760

1078

case AVAHI_BROWSER_NEW:

1763

1081

the callback function is called the Avahi server will free the

1764

1082

resolver for us. */

1765

1083

1766

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

1767

interface, protocol, name, type,

1768

domain, protocol, 0,

1769

resolve_callback, mc) == NULL)

1084

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

1085

name, type, domain, protocol, 0,

1086

resolve_callback, NULL) == NULL)

1770

1087

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

1771

1088

" %s\n", name,

1772

avahi_strerror(avahi_server_errno

1773

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

1089

avahi_strerror(avahi_server_errno(mc.server)));

1774

1090

break;

1775

1091

1776

1092

case AVAHI_BROWSER_REMOVE:

1795

1111

signal_received = sig;

1796

1112

int old_errno = errno;

1797

1113

/* set main loop to exit */

1798

if(simple_poll != NULL){

1799

avahi_simple_poll_quit(simple_poll);

1114

if(mc.simple_poll != NULL){

1115

avahi_simple_poll_quit(mc.simple_poll);

1800

1116

}

1801

1117

errno = old_errno;

1802

1118

}

1803

1119

1804

__attribute__((nonnull, warn_unused_result))

1805

1120

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

1806

1121

int ret;

1807

int old_errno;

1808

1122

1809

1123

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

1810

1124

if(s < 0){

1811

old_errno = errno;

1812

1125

perror_plus("socket");

1813

errno = old_errno;

1814

1126

return false;

1815

1127

}

1816

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

1817

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

1128

strcpy(ifr->ifr_name, ifname);

1818

1129

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1819

1130

if(ret == -1){

1820

1131

if(debug){

1821

old_errno = errno;

1822

1132

perror_plus("ioctl SIOCGIFFLAGS");

1823

errno = old_errno;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1829

1133

}

1830

1134

return false;

1831

1135

}

1832

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

1833

old_errno = errno;

1834

perror_plus("close");

1835

errno = old_errno;

1836

}

1837

1136

return true;

1838

1137

}

1839

1138

1840

__attribute__((nonnull, warn_unused_result))

1841

1139

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

1842

1140

1843

1141

/* Reject the loopback device */

1885

1183

* corresponds to an acceptable network device.

1886

1184

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

1887

1185

*/

1888

__attribute__((nonnull, warn_unused_result))

1889

1186

int good_interface(const struct dirent *if_entry){

1890

1187

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

1891

1188

return 0;

1907

1204

}

1908

1205

1909

1206

/*

1910

* This function determines if a network interface is up.

1911

*/

1912

__attribute__((nonnull, warn_unused_result))

1913

bool interface_is_up(const char *interface){

1914

struct ifreq ifr;

1915

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

1916

if(debug){

1917

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

1918

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

1919

}

1920

return false;

1921

}

1922

1923

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

1924

}

1925

1926

/*

1927

* This function determines if a network interface is running

1928

*/

1929

__attribute__((nonnull, warn_unused_result))

1930

bool interface_is_running(const char *interface){

1931

struct ifreq ifr;

1932

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

1933

if(debug){

1934

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

1935

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

1936

}

1937

return false;

1938

}

1939

1940

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

1941

}

1942

1943

__attribute__((nonnull, pure, warn_unused_result))

1207

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

1208

* corresponds to an acceptable network device which is up.

1209

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

1210

*/

1211

int up_interface(const struct dirent *if_entry){

1212

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

1213

return 0;

1214

}

1215

1216

struct ifreq ifr;

1217

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

1218

if(debug){

1219

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

1220

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

1221

}

1222

return 0;

1223

}

1224

1225

/* Reject down interfaces */

1226

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

1227

if(debug){

1228

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

1229

if_entry->d_name);

1230

}

1231

return 0;

1232

}

1233

1234

/* Reject non-running interfaces */

1235

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

1236

if(debug){

1237

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

1238

if_entry->d_name);

1239

}

1240

return 0;

1241

}

1242

1243

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

1244

return 0;

1245

}

1246

return 1;

1247

}

1248

1944

1249

int notdotentries(const struct dirent *direntry){

1945

1250

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

1946

1251

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

1953

1258

}

1954

1259

1955

1260

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

1956

__attribute__((nonnull, warn_unused_result))

1957

1261

int runnable_hook(const struct dirent *direntry){

1958

1262

int ret;

1959

1263

size_t sret;

1967

1271

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

1968

1272

"abcdefghijklmnopqrstuvwxyz"

1969

1273

"0123456789"

1970

"_.-");

1274

"_-");

1971

1275

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

1972

1276

/* Contains non-allowed characters */

1973

1277

if(debug){

1977

1281

return 0;

1978

1282

}

1979

1283

1980

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

1284

char *fullname = NULL;

1285

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

1286

if(ret < 0){

1287

perror_plus("asprintf");

1288

return 0;

1289

}

1290

1291

ret = stat(fullname, &st);

1981

1292

if(ret == -1){

1982

1293

if(debug){

1983

1294

perror_plus("Could not stat hook");

2007

1318

return 1;

2008

1319

}

2009

1320

2010

__attribute__((nonnull, warn_unused_result))

2011

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2012

mandos_context *mc){

1321

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2013

1322

int ret;

2014

1323

struct timespec now;

2015

1324

struct timespec waited_time;

2016

1325

intmax_t block_time;

2017

1326

2018

1327

while(true){

2019

if(mc->current_server == NULL){

2020

if(debug){

1328

if(mc.current_server == NULL){

1329

if (debug){

2021

1330

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

2022

1331

" No timeout!\n");

2023

1332

}

2024

1333

ret = avahi_simple_poll_iterate(s, -1);

2025

1334

} else {

2026

if(debug){

1335

if (debug){

2027

1336

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

2028

1337

" it, or wait\n");

2029

1338

}

2036

1345

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

2037

1346

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

2038

1347

waited_time.tv_sec = (now.tv_sec

2039

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

1348

- mc.current_server->last_seen.tv_sec);

2040

1349

waited_time.tv_nsec = (now.tv_nsec

2041

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

1350

- mc.current_server->last_seen.tv_nsec);

2042

1351

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

2043

1352

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

2044

1353

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

2046

1355

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

2047

1356

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

2048

1357

2049

if(debug){

1358

if (debug){

2050

1359

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

2051

1360

block_time);

2052

1361

}

2053

1362

2054

1363

if(block_time <= 0){

2055

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

2056

mc->current_server->port,

2057

mc->current_server->if_index,

2058

mc->current_server->af, mc);

1364

ret = start_mandos_communication(mc.current_server->ip,

1365

mc.current_server->port,

1366

mc.current_server->if_index,

1367

mc.current_server->af);

2059

1368

if(ret == 0){

2060

avahi_simple_poll_quit(s);

1369

avahi_simple_poll_quit(mc.simple_poll);

2061

1370

return 0;

2062

1371

}

2063

1372

ret = clock_gettime(CLOCK_MONOTONIC,

2064

&mc->current_server->last_seen);

1373

&mc.current_server->last_seen);

2065

1374

if(ret == -1){

2066

1375

perror_plus("clock_gettime");

2067

1376

return -1;

2068

1377

}

2069

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

1378

mc.current_server = mc.current_server->next;

2070

1379

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

2071

1380

servers, but don't block */

2072

1381

}

2074

1383

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

2075

1384

}

2076

1385

if(ret != 0){

2077

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

1386

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

2078

1387

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

2079

1388

}

2080

1389

}

2081

1390

}

2082

1391

}

2083

1392

2084

__attribute__((nonnull))

2085

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

1393

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

2086

1394

const float delay){

2087

struct dirent **direntries = NULL;

2088

if(hookdir_fd == -1){

2089

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2090

| O_CLOEXEC);

2091

if(hookdir_fd == -1){

2092

if(errno == ENOENT){

2093

if(debug){

2094

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

2095

" found\n", hookdir);

2096

}

2097

} else {

2098

perror_plus("open");

2099

}

2100

return;

2101

}

2102

}

2103

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

2104

if(devnull == -1){

2105

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

2106

return;

2107

}

2108

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

2109

runnable_hook, alphasort);

1395

struct dirent **direntries;

1396

struct dirent *direntry;

1397

int ret;

1398

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

1399

alphasort);

2110

1400

if(numhooks == -1){

2111

1401

perror_plus("scandir");

2112

close(devnull);

2113

return;

2114

}

2115

struct dirent *direntry;

2116

int ret;

2117

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

2118

direntry = direntries[i];

2119

if(debug){

2120

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

2121

direntry->d_name);

2122

}

2123

pid_t hook_pid = fork();

2124

if(hook_pid == 0){

2125

/* Child */

2126

/* Raise privileges */

2127

errno = raise_privileges_permanently();

2128

if(errno != 0){

2129

perror_plus("Failed to raise privileges");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Set group */

2133

errno = 0;

2134

ret = setgid(0);

2135

if(ret == -1){

2136

perror_plus("setgid");

2137

_exit(EX_NOPERM);

2138

}

2139

/* Reset supplementary groups */

2140

errno = 0;

2141

ret = setgroups(0, NULL);

2142

if(ret == -1){

2143

perror_plus("setgroups");

2144

_exit(EX_NOPERM);

2145

}

2146

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

2147

if(ret == -1){

2148

perror_plus("setenv");

2149

_exit(EX_OSERR);

2150

}

2151

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

2152

if(ret == -1){

2153

perror_plus("setenv");

2154

_exit(EX_OSERR);

2155

}

2156

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

2157

if(ret == -1){

2158

perror_plus("setenv");

2159

_exit(EX_OSERR);

2160

}

2161

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

2162

if(ret == -1){

2163

perror_plus("setenv");

2164

_exit(EX_OSERR);

2165

}

2166

char *delaystring;

2167

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

2168

if(ret == -1){

1402

} else {

1403

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

1404

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

1405

direntry = direntries[i];

1406

char *fullname = NULL;

1407

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

1408

if(ret < 0){

2169

1409

perror_plus("asprintf");

2170

_exit(EX_OSERR);

2171

}

2172

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

2173

if(ret == -1){

1410

continue;

1411

}

1412

if(debug){

1413

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

1414

direntry->d_name);

1415

}

1416

pid_t hook_pid = fork();

1417

if(hook_pid == 0){

1418

/* Child */

1419

/* Raise privileges */

1420

errno = 0;

1421

ret = seteuid(0);

1422

if(ret == -1){

1423

perror_plus("seteuid");

1424

}

1425

/* Raise privileges even more */

1426

errno = 0;

1427

ret = setuid(0);

1428

if(ret == -1){

1429

perror_plus("setuid");

1430

}

1431

/* Set group */

1432

errno = 0;

1433

ret = setgid(0);

1434

if(ret == -1){

1435

perror_plus("setgid");

1436

}

1437

/* Reset supplementary groups */

1438

errno = 0;

1439

ret = setgroups(0, NULL);

1440

if(ret == -1){

1441

perror_plus("setgroups");

1442

}

1443

dup2(devnull, STDIN_FILENO);

1444

close(devnull);

1445

dup2(STDERR_FILENO, STDOUT_FILENO);

1446

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

1447

if(ret == -1){

1448

perror_plus("setenv");

1449

_exit(EX_OSERR);

1450

}

1451

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

1452

if(ret == -1){

1453

perror_plus("setenv");

1454

_exit(EX_OSERR);

1455

}

1456

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

1457

if(ret == -1){

1458

perror_plus("setenv");

1459

_exit(EX_OSERR);

1460

}

1461

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

1462

if(ret == -1){

1463

perror_plus("setenv");

1464

_exit(EX_OSERR);

1465

}

1466

char *delaystring;

1467

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

1468

if(ret == -1){

1469

perror_plus("asprintf");

1470

_exit(EX_OSERR);

1471

}

1472

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

1473

if(ret == -1){

1474

free(delaystring);

1475

perror_plus("setenv");

1476

_exit(EX_OSERR);

1477

}

2174

1478

free(delaystring);

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

free(delaystring);

2179

if(connect_to != NULL){

2180

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

2181

if(ret == -1){

2182

perror_plus("setenv");

2183

_exit(EX_OSERR);

2184

}

2185

}

2186

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

2187

direntry->d_name,

2188

O_RDONLY));

2189

if(hook_fd == -1){

2190

perror_plus("openat");

2191

_exit(EXIT_FAILURE);

2192

}

2193

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

2194

perror_plus("close");

2195

_exit(EXIT_FAILURE);

2196

}

2197

ret = dup2(devnull, STDIN_FILENO);

2198

if(ret == -1){

2199

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

2200

_exit(EX_OSERR);

2201

}

2202

ret = close(devnull);

2203

if(ret == -1){

2204

perror_plus("close");

2205

_exit(EX_OSERR);

2206

}

2207

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2208

if(ret == -1){

2209

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

2210

_exit(EX_OSERR);

2211

}

2212

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

2213

environ) == -1){

2214

perror_plus("fexecve");

2215

_exit(EXIT_FAILURE);

2216

}

2217

} else {

2218

if(hook_pid == -1){

2219

perror_plus("fork");

2220

free(direntry);

2221

continue;

2222

}

2223

int status;

2224

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

2225

perror_plus("waitpid");

2226

free(direntry);

2227

continue;

2228

}

2229

if(WIFEXITED(status)){

2230

if(WEXITSTATUS(status) != 0){

2231

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

2232

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

2233

WEXITSTATUS(status));

2234

free(direntry);

2235

continue;

2236

}

2237

} else if(WIFSIGNALED(status)){

2238

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

2239

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

2240

WTERMSIG(status));

2241

free(direntry);

2242

continue;

2243

} else {

2244

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

2245

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

2246

free(direntry);

2247

continue;

2248

}

2249

}

2250

if(debug){

2251

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

2252

direntry->d_name);

2253

}

2254

free(direntry);

2255

}

2256

free(direntries);

2257

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

2258

perror_plus("close");

2259

} else {

2260

hookdir_fd = -1;

2261

}

2262

close(devnull);

2263

}

2264

2265

__attribute__((nonnull, warn_unused_result))

2266

int bring_up_interface(const char *const interface,

2267

const float delay){

2268

int old_errno = errno;

2269

int ret;

2270

struct ifreq network;

2271

unsigned int if_index = if_nametoindex(interface);

2272

if(if_index == 0){

2273

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

2274

errno = old_errno;

2275

return ENXIO;

2276

}

2277

2278

if(quit_now){

2279

errno = old_errno;

2280

return EINTR;

2281

}

2282

2283

if(not interface_is_up(interface)){

2284

int ret_errno = 0;

2285

int ioctl_errno = 0;

2286

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

2287

ret_errno = errno;

2288

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

2289

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

2290

errno = old_errno;

2291

return ret_errno;

2292

}

2293

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

2294

2295

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

2296

if(sd == -1){

2297

ret_errno = errno;

2298

perror_plus("socket");

2299

errno = old_errno;

2300

return ret_errno;

2301

}

2302

2303

if(quit_now){

2304

ret = close(sd);

2305

if(ret == -1){

2306

perror_plus("close");

2307

}

2308

errno = old_errno;

2309

return EINTR;

2310

}

2311

2312

if(debug){

2313

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

2314

interface);

2315

}

2316

2317

/* Raise privileges */

2318

ret_errno = raise_privileges();

2319

if(ret_errno != 0){

2320

errno = ret_errno;

2321

perror_plus("Failed to raise privileges");

2322

}

2323

2324

#ifdef __linux__

2325

int ret_linux;

2326

bool restore_loglevel = false;

2327

if(ret_errno == 0){

2328

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2329

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

2330

ret_linux = klogctl(8, NULL, 5);

2331

if(ret_linux == -1){

2332

perror_plus("klogctl");

2333

} else {

2334

restore_loglevel = true;

2335

}

2336

}

2337

#endif /* __linux__ */

2338

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

2339

ioctl_errno = errno;

2340

#ifdef __linux__

2341

if(restore_loglevel){

2342

ret_linux = klogctl(7, NULL, 0);

2343

if(ret_linux == -1){

2344

perror_plus("klogctl");

2345

}

2346

}

2347

#endif /* __linux__ */

2348

2349

/* If raise_privileges() succeeded above */

2350

if(ret_errno == 0){

2351

/* Lower privileges */

2352

ret_errno = lower_privileges();

2353

if(ret_errno != 0){

2354

errno = ret_errno;

2355

perror_plus("Failed to lower privileges");

2356

}

2357

}

2358

2359

/* Close the socket */

2360

ret = close(sd);

2361

if(ret == -1){

2362

perror_plus("close");

2363

}

2364

2365

if(ret_setflags == -1){

2366

errno = ioctl_errno;

2367

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2368

errno = old_errno;

2369

return ioctl_errno;

2370

}

2371

} else if(debug){

2372

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

2373

interface);

2374

}

2375

2376

/* Sleep checking until interface is running.

2377

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

2378

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

2379

if(interface_is_running(interface)){

2380

break;

2381

}

2382

struct timespec sleeptime = { .tv_nsec = 250000000 };

2383

ret = nanosleep(&sleeptime, NULL);

2384

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

2385

perror_plus("nanosleep");

2386

}

2387

}

2388

2389

errno = old_errno;

2390

return 0;

2391

}

2392

2393

__attribute__((nonnull, warn_unused_result))

2394

int take_down_interface(const char *const interface){

2395

int old_errno = errno;

2396

struct ifreq network;

2397

unsigned int if_index = if_nametoindex(interface);

2398

if(if_index == 0){

2399

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

2400

errno = old_errno;

2401

return ENXIO;

2402

}

2403

if(interface_is_up(interface)){

2404

int ret_errno = 0;

2405

int ioctl_errno = 0;

2406

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

2407

ret_errno = errno;

2408

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

2409

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

2410

errno = old_errno;

2411

return ret_errno;

2412

}

2413

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

2414

2415

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

2416

if(sd == -1){

2417

ret_errno = errno;

2418

perror_plus("socket");

2419

errno = old_errno;

2420

return ret_errno;

2421

}

2422

2423

if(debug){

2424

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

2425

interface);

2426

}

2427

2428

/* Raise privileges */

2429

ret_errno = raise_privileges();

2430

if(ret_errno != 0){

2431

errno = ret_errno;

2432

perror_plus("Failed to raise privileges");

2433

}

2434

2435

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

2436

ioctl_errno = errno;

2437

2438

/* If raise_privileges() succeeded above */

2439

if(ret_errno == 0){

2440

/* Lower privileges */

2441

ret_errno = lower_privileges();

2442

if(ret_errno != 0){

2443

errno = ret_errno;

2444

perror_plus("Failed to lower privileges");

2445

}

2446

}

2447

2448

/* Close the socket */

2449

int ret = close(sd);

2450

if(ret == -1){

2451

perror_plus("close");

2452

}

2453

2454

if(ret_setflags == -1){

2455

errno = ioctl_errno;

2456

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2457

errno = old_errno;

2458

return ioctl_errno;

2459

}

2460

} else if(debug){

2461

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

2462

interface);

2463

}

2464

2465

errno = old_errno;

2466

return 0;

1479

if(connect_to != NULL){

1480

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

1481

if(ret == -1){

1482

perror_plus("setenv");

1483

_exit(EX_OSERR);

1484

}

1485

}

1486

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

1487

perror_plus("execl");

1488

_exit(EXIT_FAILURE);

1489

}

1490

} else {

1491

int status;

1492

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

1493

perror_plus("waitpid");

1494

free(fullname);

1495

continue;

1496

}

1497

if(WIFEXITED(status)){

1498

if(WEXITSTATUS(status) != 0){

1499

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

1500

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

1501

WEXITSTATUS(status));

1502

free(fullname);

1503

continue;

1504

}

1505

} else if(WIFSIGNALED(status)){

1506

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

1507

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

1508

WTERMSIG(status));

1509

free(fullname);

1510

continue;

1511

} else {

1512

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

1513

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

1514

free(fullname);

1515

continue;

1516

}

1517

}

1518

free(fullname);

1519

if(debug){

1520

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

1521

direntry->d_name);

1522

}

1523

}

1524

close(devnull);

1525

}

1526

return true;

2467

1527

}

2468

1528

2469

1529

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

2470

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

2471

#if GNUTLS_VERSION_NUMBER >= 0x030606

2472

.priority = "SECURE128:!CTYPE-X.509"

2473

":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"

2474

":%PROFILE_ULTRA",

2475

#elif GNUTLS_VERSION_NUMBER < 0x030600

2476

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

2477

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

2478

#else

2479

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

2480

#endif

2481

.current_server = NULL, .interfaces = NULL,

2482

.interfaces_size = 0 };

2483

1530

AvahiSServiceBrowser *sb = NULL;

2484

error_t ret_errno;

1531

int error;

2485

1532

int ret;

2486

1533

intmax_t tmpmax;

2487

1534

char *tmp;

2488

1535

int exitcode = EXIT_SUCCESS;

2489

char *interfaces_to_take_down = NULL;

2490

size_t interfaces_to_take_down_size = 0;

2491

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

2492

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

2493

char *tempdir = NULL;

1536

const char *interface = "";

1537

struct ifreq network;

1538

int sd = -1;

1539

bool take_down_interface = false;

1540

uid_t uid;

1541

gid_t gid;

1542

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

1543

bool tempdir_created = false;

2494

1544

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2495

1545

const char *seckey = PATHDIR "/" SECKEY;

2496

1546

const char *pubkey = PATHDIR "/" PUBKEY;

2497

#if GNUTLS_VERSION_NUMBER >= 0x030606

2498

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2499

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2500

#endif

2501

const char *dh_params_file = NULL;

2502

char *interfaces_hooks = NULL;

2503

1547

2504

1548

bool gnutls_initialized = false;

2505

1549

bool gpgme_initialized = false;

2551

1595

{ .name = "pubkey", .key = 'p',

2552

1596

.arg = "FILE",

2553

1597

.doc = "OpenPGP public key file base name",

2554

.group = 1 },

2555

{ .name = "tls-privkey", .key = 't',

2556

.arg = "FILE",

2557

#if GNUTLS_VERSION_NUMBER >= 0x030606

2558

.doc = "TLS private key file base name",

2559

#else

2560

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2561

#endif

2562

.group = 1 },

2563

{ .name = "tls-pubkey", .key = 'T',

2564

.arg = "FILE",

2565

#if GNUTLS_VERSION_NUMBER >= 0x030606

2566

.doc = "TLS public key file base name",

2567

#else

2568

.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",

2569

#endif

2570

.group = 1 },

1598

.group = 2 },

2571

1599

{ .name = "dh-bits", .key = 129,

2572

1600

.arg = "BITS",

2573

1601

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

2574

1602

" Diffie-Hellman key exchange",

2575

1603

.group = 2 },

2576

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

2577

.arg = "FILE",

2578

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

2579

" for the Diffie-Hellman key exchange",

2580

.group = 2 },

2581

1604

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

2582

1605

.arg = "STRING",

2583

1606

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

2617

1640

connect_to = arg;

2618

1641

break;

2619

1642

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

2620

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

2621

arg, (int)',');

2622

if(ret_errno != 0){

2623

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

2624

}

1643

interface = arg;

2625

1644

break;

2626

1645

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

2627

1646

seckey = arg;

2629

1648

case 'p': /* --pubkey */

2630

1649

pubkey = arg;

2631

1650

break;

2632

case 't': /* --tls-privkey */

2633

#if GNUTLS_VERSION_NUMBER >= 0x030606

2634

tls_privkey = arg;

2635

#endif

2636

break;

2637

case 'T': /* --tls-pubkey */

2638

#if GNUTLS_VERSION_NUMBER >= 0x030606

2639

tls_pubkey = arg;

2640

#endif

2641

break;

2642

1651

case 129: /* --dh-bits */

2643

1652

errno = 0;

2644

1653

tmpmax = strtoimax(arg, &tmp, 10);

2648

1657

}

2649

1658

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

2650

1659

break;

2651

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

2652

dh_params_file = arg;

2653

break;

2654

1660

case 130: /* --priority */

2655

1661

mc.priority = arg;

2656

1662

break;

2679

1685

argp_state_help(state, state->out_stream,

2680

1686

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2681

1687

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2682

__builtin_unreachable();

2683

1688

case -3: /* --usage */

2684

1689

argp_state_help(state, state->out_stream,

2685

1690

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2686

__builtin_unreachable();

2687

1691

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

2688

1692

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

2689

1693

exit(argp_err_exit_status);

2698

1702

.args_doc = "",

2699

1703

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

2700

1704

" passwords from a Mandos server" };

2701

ret_errno = argp_parse(&argp, argc, argv,

2702

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2703

switch(ret_errno){

1705

ret = argp_parse(&argp, argc, argv,

1706

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1707

switch(ret){

2704

1708

case 0:

2705

1709

break;

2706

1710

case ENOMEM:

2707

1711

default:

2708

errno = ret_errno;

1712

errno = ret;

2709

1713

perror_plus("argp_parse");

2710

1714

exitcode = EX_OSERR;

2711

1715

goto end;

2714

1718

goto end;

2715

1719

}

2716

1720

}

2717

1721

2718

1722

{

2719

1723

/* Work around Debian bug #633582:

2720

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

1724

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

2721

1725

2722

/* Re-raise privileges */

2723

ret = raise_privileges();

2724

if(ret != 0){

2725

errno = ret;

2726

perror_plus("Failed to raise privileges");

1726

/* Re-raise priviliges */

1727

errno = 0;

1728

ret = seteuid(0);

1729

if(ret == -1){

1730

perror_plus("seteuid");

2727

1731

} else {

2728

1732

struct stat st;

2729

1733

2744

1748

}

2745

1749

}

2746

1750

}

2747

close(seckey_fd);

1751

TEMP_FAILURE_RETRY(close(seckey_fd));

2748

1752

}

2749

1753

}

2750

1754

2751

1755

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

2752

1756

int pubkey_fd = open(pubkey, O_RDONLY);

2753

1757

if(pubkey_fd == -1){

2765

1769

}

2766

1770

}

2767

1771

}

2768

close(pubkey_fd);

2769

}

2770

}

2771

2772

if(dh_params_file != NULL

2773

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

2774

int dhparams_fd = open(dh_params_file, O_RDONLY);

2775

if(dhparams_fd == -1){

2776

perror_plus("open");

2777

} else {

2778

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

2779

if(ret == -1){

2780

perror_plus("fstat");

2781

} else {

2782

if(S_ISREG(st.st_mode)

2783

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

2784

ret = fchown(dhparams_fd, uid, gid);

2785

if(ret == -1){

2786

perror_plus("fchown");

2787

}

2788

}

2789

}

2790

close(dhparams_fd);

2791

}

2792

}

2793

1772

TEMP_FAILURE_RETRY(close(pubkey_fd));

1773

}

1774

}

1775

2794

1776

/* Lower privileges */

2795

ret = lower_privileges();

2796

if(ret != 0){

2797

errno = ret;

2798

perror_plus("Failed to lower privileges");

2799

}

2800

}

2801

}

2802

2803

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

2804

{

2805

char *interface = NULL;

2806

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

2807

interface))){

2808

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

2809

and if_nametoindex(interface) == 0){

2810

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

2811

fprintf_plus(stderr, "Not using nonexisting interface"

2812

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

2813

}

2814

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

2815

interface = NULL;

1777

errno = 0;

1778

ret = seteuid(uid);

1779

if(ret == -1){

1780

perror_plus("seteuid");

2816

1781

}

2817

1782

}

2818

1783

}

2819

1784

2820

1785

/* Run network hooks */

2821

{

2822

if(mc.interfaces != NULL){

2823

interfaces_hooks = malloc(mc.interfaces_size);

2824

if(interfaces_hooks == NULL){

2825

perror_plus("malloc");

2826

goto end;

2827

}

2828

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

2829

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

2830

}

2831

run_network_hooks("start", interfaces_hooks != NULL ?

2832

interfaces_hooks : "", delay);

1786

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

1787

goto end;

2833

1788

}

2834

1789

2835

1790

if(not debug){

2836

1791

avahi_set_log_function(empty_log);

2837

1792

}

2838

1793

1794

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

1795

struct dirent **direntries;

1796

/* First look for interfaces that are up */

1797

ret = scandir(sys_class_net, &direntries, up_interface,

1798

alphasort);

1799

if(ret == 0){

1800

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

1801

free(direntries);

1802

ret = scandir(sys_class_net, &direntries, good_interface,

1803

alphasort);

1804

}

1805

if(ret >= 1){

1806

/* Pick the first interface returned */

1807

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

1808

if(debug){

1809

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

1810

}

1811

if(interface == NULL){

1812

perror_plus("malloc");

1813

free(direntries);

1814

exitcode = EXIT_FAILURE;

1815

goto end;

1816

}

1817

free(direntries);

1818

} else {

1819

free(direntries);

1820

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

1821

exitcode = EXIT_FAILURE;

1822

goto end;

1823

}

1824

}

1825

2839

1826

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

2840

1827

from the signal handler */

2841

1828

/* Initialize the pseudo-RNG for Avahi */

2842

1829

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

2843

simple_poll = avahi_simple_poll_new();

2844

if(simple_poll == NULL){

1830

mc.simple_poll = avahi_simple_poll_new();

1831

if(mc.simple_poll == NULL){

2845

1832

fprintf_plus(stderr,

2846

1833

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

2847

1834

exitcode = EX_UNAVAILABLE;

2911

1898

}

2912

1899

}

2913

1900

2914

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

2915

if(mc.interfaces == NULL){

2916

struct dirent **direntries = NULL;

2917

/* Look for any good interfaces */

2918

ret = scandir(sys_class_net, &direntries, good_interface,

2919

alphasort);

2920

if(ret >= 1){

2921

/* Add all found interfaces to interfaces list */

2922

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

2923

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

2924

direntries[i]->d_name);

2925

if(ret_errno != 0){

2926

errno = ret_errno;

2927

perror_plus("argz_add");

2928

free(direntries[i]);

2929

continue;

2930

}

2931

if(debug){

2932

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

2933

direntries[i]->d_name);

2934

}

2935

free(direntries[i]);

2936

}

2937

free(direntries);

2938

} else {

2939

if(ret == 0){

2940

free(direntries);

2941

}

2942

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

2943

exitcode = EXIT_FAILURE;

2944

goto end;

2945

}

2946

}

2947

2948

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

2949

{

2950

char *interface = NULL;

2951

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

2952

interface))){

2953

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

2954

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

2955

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

2956

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

2957

interface);

2958

interface = NULL;

2959

while((interface = argz_next(mc.interfaces,

2960

mc.interfaces_size, interface))){

2961

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

2962

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

2963

interface);

2964

interface = NULL;

1901

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

1902

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

1903

if_index = (AvahiIfIndex) if_nametoindex(interface);

1904

if(if_index == 0){

1905

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

1906

exitcode = EX_UNAVAILABLE;

1907

goto end;

1908

}

1909

1910

if(quit_now){

1911

goto end;

1912

}

1913

1914

/* Re-raise priviliges */

1915

errno = 0;

1916

ret = seteuid(0);

1917

if(ret == -1){

1918

perror_plus("seteuid");

1919

}

1920

1921

#ifdef __linux__

1922

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1923

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

1924

ret = klogctl(8, NULL, 5);

1925

bool restore_loglevel = true;

1926

if(ret == -1){

1927

restore_loglevel = false;

1928

perror_plus("klogctl");

1929

}

1930

#endif /* __linux__ */

1931

1932

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1933

if(sd < 0){

1934

perror_plus("socket");

1935

exitcode = EX_OSERR;

1936

#ifdef __linux__

1937

if(restore_loglevel){

1938

ret = klogctl(7, NULL, 0);

1939

if(ret == -1){

1940

perror_plus("klogctl");

1941

}

1942

}

1943

#endif /* __linux__ */

1944

/* Lower privileges */

1945

errno = 0;

1946

ret = seteuid(uid);

1947

if(ret == -1){

1948

perror_plus("seteuid");

1949

}

1950

goto end;

1951

}

1952

strcpy(network.ifr_name, interface);

1953

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

1954

if(ret == -1){

1955

perror_plus("ioctl SIOCGIFFLAGS");

1956

#ifdef __linux__

1957

if(restore_loglevel){

1958

ret = klogctl(7, NULL, 0);

1959

if(ret == -1){

1960

perror_plus("klogctl");

1961

}

1962

}

1963

#endif /* __linux__ */

1964

exitcode = EX_OSERR;

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

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

1974

network.ifr_flags |= IFF_UP;

1975

take_down_interface = true;

1976

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

1977

if(ret == -1){

1978

take_down_interface = false;

1979

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1980

exitcode = EX_OSERR;

1981

#ifdef __linux__

1982

if(restore_loglevel){

1983

ret = klogctl(7, NULL, 0);

1984

if(ret == -1){

1985

perror_plus("klogctl");

2965

1986

}

2966

1987

}

1988

#endif /* __linux__ */

1989

/* Lower privileges */

1990

errno = 0;

1991

ret = seteuid(uid);

1992

if(ret == -1){

1993

perror_plus("seteuid");

1994

}

1995

goto end;

1996

}

1997

}

1998

/* Sleep checking until interface is running.

1999

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

2000

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

2001

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

2002

if(ret == -1){

2003

perror_plus("ioctl SIOCGIFFLAGS");

2004

} else if(network.ifr_flags & IFF_RUNNING){

2967

2005

break;

2968

2006

}

2969

bool interface_was_up = interface_is_up(interface);

2970

errno = bring_up_interface(interface, delay);

2971

if(not interface_was_up){

2972

if(errno != 0){

2973

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

2974

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

2975

} else {

2976

errno = argz_add(&interfaces_to_take_down,

2977

&interfaces_to_take_down_size,

2978

interface);

2979

if(errno != 0){

2980

perror_plus("argz_add");

2981

}

2982

}

2983

}

2984

}

2985

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

2986

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

2987

}

2988

}

2989

2990

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

2991

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

2992

if(debug){

2993

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

2994

mc.interfaces);

2995

}

2996

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

2007

struct timespec sleeptime = { .tv_nsec = 250000000 };

2008

ret = nanosleep(&sleeptime, NULL);

2009

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

2010

perror_plus("nanosleep");

2011

}

2012

}

2013

if(not take_down_interface){

2014

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

2015

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

2016

if(ret == -1){

2017

perror_plus("close");

2018

}

2019

}

2020

#ifdef __linux__

2021

if(restore_loglevel){

2022

/* Restores kernel loglevel to default */

2023

ret = klogctl(7, NULL, 0);

2024

if(ret == -1){

2025

perror_plus("klogctl");

2026

}

2027

}

2028

#endif /* __linux__ */

2029

/* Lower privileges */

2030

errno = 0;

2031

/* Lower privileges */

2032

ret = seteuid(uid);

2033

if(ret == -1){

2034

perror_plus("seteuid");

2035

}

2997

2036

}

2998

2037

2999

2038

if(quit_now){

3000

2039

goto end;

3001

2040

}

3002

2041

3003

#if GNUTLS_VERSION_NUMBER >= 0x030606

3004

ret = init_gnutls_global(tls_pubkey, tls_privkey, dh_params_file, &mc);

3005

#elif GNUTLS_VERSION_NUMBER < 0x030600

3006

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

3007

#else

3008

#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"

3009

#endif

2042

ret = init_gnutls_global(pubkey, seckey);

3010

2043

if(ret == -1){

3011

2044

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

3012

2045

exitcode = EX_UNAVAILABLE;

3019

2052

goto end;

3020

2053

}

3021

2054

3022

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

3023

tempdir = mkdtemp(run_tempdir);

3024

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

3025

if(debug){

3026

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

3027

run_tempdir, old_tempdir);

3028

}

3029

tempdir = mkdtemp(old_tempdir);

3030

}

3031

if(tempdir == NULL){

2055

if(mkdtemp(tempdir) == NULL){

3032

2056

perror_plus("mkdtemp");

3033

2057

goto end;

3034

2058

}

2059

tempdir_created = true;

3035

2060

3036

2061

if(quit_now){

3037

2062

goto end;

3038

2063

}

3039

2064

3040

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

2065

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

3041

2066

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

3042

2067

exitcode = EX_UNAVAILABLE;

3043

2068

goto end;

3053

2078

/* Connect directly, do not use Zeroconf */

3054

2079

/* (Mainly meant for debugging) */

3055

2080

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

3056

3057

2081

if(address == NULL){

3058

2082

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

3059

2083

exitcode = EX_USAGE;

3064

2088

goto end;

3065

2089

}

3066

2090

3067

in_port_t port;

2091

uint16_t port;

3068

2092

errno = 0;

3069

2093

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

3070

2094

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

3071

or tmpmax != (in_port_t)tmpmax){

2095

or tmpmax != (uint16_t)tmpmax){

3072

2096

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

3073

2097

exitcode = EX_USAGE;

3074

2098

goto end;

3075

2099

}

3076

2100

3077

2101

if(quit_now){

3078

2102

goto end;

3079

2103

}

3080

2104

3081

port = (in_port_t)tmpmax;

2105

port = (uint16_t)tmpmax;

3082

2106

*address = '\0';

3083

2107

/* Colon in address indicates IPv6 */

3084

2108

int af;

3100

2124

}

3101

2125

3102

2126

while(not quit_now){

3103

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

3104

&mc);

2127

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

3105

2128

if(quit_now or ret == 0){

3106

2129

break;

3107

2130

}

3109

2132

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

3110

2133

(int)retry_interval);

3111

2134

}

3112

sleep((unsigned int)retry_interval);

2135

sleep((int)retry_interval);

3113

2136

}

3114

2137

3115

if(not quit_now){

2138

if (not quit_now){

3116

2139

exitcode = EXIT_SUCCESS;

3117

2140

}

3118

2141

3133

2156

config.publish_domain = 0;

3134

2157

3135

2158

/* Allocate a new server */

3136

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3137

&config, NULL, NULL, &ret);

2159

mc.server = avahi_server_new(avahi_simple_poll_get

2160

(mc.simple_poll), &config, NULL,

2161

NULL, &error);

3138

2162

3139

2163

/* Free the Avahi configuration data */

3140

2164

avahi_server_config_free(&config);

3143

2167

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

3144

2168

if(mc.server == NULL){

3145

2169

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

3146

avahi_strerror(ret));

2170

avahi_strerror(error));

3147

2171

exitcode = EX_UNAVAILABLE;

3148

2172

goto end;

3149

2173

}

3155

2179

/* Create the Avahi service browser */

3156

2180

sb = avahi_s_service_browser_new(mc.server, if_index,

3157

2181

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3158

NULL, 0, browse_callback,

3159

(void *)&mc);

2182

NULL, 0, browse_callback, NULL);

3160

2183

if(sb == NULL){

3161

2184

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

3162

2185

avahi_strerror(avahi_server_errno(mc.server)));

3173

2196

if(debug){

3174

2197

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

3175

2198

}

3176

3177

ret = avahi_loop_with_timeout(simple_poll,

3178

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

2199

2200

ret = avahi_loop_with_timeout(mc.simple_poll,

2201

(int)(retry_interval * 1000));

3179

2202

if(debug){

3180

2203

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

3181

2204

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

3184

2207

end:

3185

2208

3186

2209

if(debug){

3187

if(signal_received){

3188

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

3189

argv[0], signal_received,

3190

strsignal(signal_received));

3191

} else {

3192

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

3193

}

2210

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

3194

2211

}

3195

2212

3196

2213

/* Cleanup things */

3197

free(mc.interfaces);

3198

3199

2214

if(sb != NULL)

3200

2215

avahi_s_service_browser_free(sb);

3201

2216

3202

2217

if(mc.server != NULL)

3203

2218

avahi_server_free(mc.server);

3204

2219

3205

if(simple_poll != NULL)

3206

avahi_simple_poll_free(simple_poll);

2220

if(mc.simple_poll != NULL)

2221

avahi_simple_poll_free(mc.simple_poll);

3207

2222

3208

2223

if(gnutls_initialized){

3209

2224

gnutls_certificate_free_credentials(mc.cred);

2225

gnutls_global_deinit();

3210

2226

gnutls_dh_params_deinit(mc.dh_params);

3211

2227

}

3212

2228

3220

2236

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

3221

2237

while(mc.current_server != NULL){

3222

2238

server *next = mc.current_server->next;

3223

#ifdef __GNUC__

3224

#pragma GCC diagnostic push

3225

#pragma GCC diagnostic ignored "-Wcast-qual"

3226

#endif

3227

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

3228

#ifdef __GNUC__

3229

#pragma GCC diagnostic pop

3230

#endif

3231

2239

free(mc.current_server);

3232

2240

mc.current_server = next;

3233

2241

}

3234

2242

}

3235

2243

3236

/* Re-raise privileges */

2244

/* Run network hooks */

2245

run_network_hooks("stop", interface, delay);

2246

2247

/* Re-raise priviliges */

3237

2248

{

3238

ret = raise_privileges();

3239

if(ret != 0){

3240

errno = ret;

3241

perror_plus("Failed to raise privileges");

3242

} else {

3243

3244

/* Run network hooks */

3245

run_network_hooks("stop", interfaces_hooks != NULL ?

3246

interfaces_hooks : "", delay);

3247

3248

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

3249

{

3250

char *interface = NULL;

3251

while((interface = argz_next(interfaces_to_take_down,

3252

interfaces_to_take_down_size,

3253

interface))){

3254

ret = take_down_interface(interface);

3255

if(ret != 0){

3256

errno = ret;

3257

perror_plus("Failed to take down interface");

3258

}

3259

}

3260

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

3261

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

3262

" down\n");

3263

}

3264

}

2249

errno = 0;

2250

ret = seteuid(0);

2251

if(ret == -1){

2252

perror_plus("seteuid");

3265

2253

}

3266

2254

3267

ret = lower_privileges_permanently();

3268

if(ret != 0){

3269

errno = ret;

3270

perror_plus("Failed to lower privileges permanently");

2255

/* Take down the network interface */

2256

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

2257

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

2258

if(ret == -1){

2259

perror_plus("ioctl SIOCGIFFLAGS");

2260

} else if(network.ifr_flags & IFF_UP){

2261

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

2262

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

2263

if(ret == -1){

2264

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2265

}

2266

}

2267

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

2268

if(ret == -1){

2269

perror_plus("close");

2270

}

3271

2271

}

3272

2272

}

3273

3274

free(interfaces_to_take_down);

3275

free(interfaces_hooks);

3276

3277

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

3278

uintmax_t level){

2273

/* Lower privileges permanently */

2274

errno = 0;

2275

ret = setuid(uid);

2276

if(ret == -1){

2277

perror_plus("setuid");

2278

}

2279

2280

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

2281

if(tempdir_created){

3279

2282

struct dirent **direntries = NULL;

3280

int dret;

3281

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

3282

O_RDONLY

3283

| O_NOFOLLOW

3284

| O_DIRECTORY

3285

| O_PATH));

3286

if(dir_fd == -1){

3287

perror_plus("open");

3288

return;

3289

}

3290

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

3291

notdotentries, alphasort);

3292

if(numentries >= 0){

2283

struct dirent *direntry = NULL;

2284

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

2285

alphasort);

2286

if (numentries > 0){

3293

2287

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

3294

if(debug){

3295

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

3296

dirname, direntries[i]->d_name);

3297

}

3298

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

3299

if(dret == -1){

3300

if(errno == EISDIR){

3301

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

3302

AT_REMOVEDIR);

3303

}

3304

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

3305

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

3306

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

3307

/* Recurse only in this special case */

3308

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

3309

dret = 0;

3310

}

3311

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

3312

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

3313

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

3314

}

3315

}

3316

free(direntries[i]);

3317

}

3318

3319

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

3320

free(direntries);

3321

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3322

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

3323

perror_plus("rmdir");

3324

}

3325

} else {

3326

perror_plus("scandirat");

3327

}

3328

close(dir_fd);

3329

}

3330

3331

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

3332

if(tempdir != NULL){

3333

clean_dir_at(-1, tempdir, 0);

2288

direntry = direntries[i];

2289

char *fullname = NULL;

2290

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

2291

direntry->d_name);

2292

if(ret < 0){

2293

perror_plus("asprintf");

2294

continue;

2295

}

2296

ret = remove(fullname);

2297

if(ret == -1){

2298

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

2299

strerror(errno));

2300

}

2301

free(fullname);

2302

}

2303

}

2304

2305

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

2306

free(direntries);

2307

if (numentries == -1){

2308

perror_plus("scandir");

2309

}

2310

ret = rmdir(tempdir);

2311

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

2312

perror_plus("rmdir");

2313

}

3334

2314

}

3335

2315

3336

2316

if(quit_now){