/mandos/release : revision 237.22.1

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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;

185

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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169

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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));

209

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

189

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

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190

}

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212

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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))

218

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

220

199

if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

222

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;

231

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}

232

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return buffer_capacity;

233

207

}

234

208

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));

241

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if(new_server == NULL){

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221

.af = af };

249

222

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));

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if(ret == -1){

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perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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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225

}

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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;

237

}

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

239

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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244

}

282

245

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

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int old_errno = errno;

287

int ret = 0;

288

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

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int old_errno = errno;

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int ret = raise_privileges();

300

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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}

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errno = old_errno;

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return ret;

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}

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

312

__attribute__((warn_unused_result))

313

int lower_privileges(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

318

}

319

errno = old_errno;

320

return ret;

321

}

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;

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

329

ret = errno;

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}

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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*/

338

__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){

249

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

250

const char *tempdir){

343

251

gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

345

253

254

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){

258

bool import_key(const char *filename){

350

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int ret;

351

260

int fd;

352

261

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

if(clock_settime(CLOCK_REALTIME, &keystat.st_mtim) != 0){

400

perror_plus("clock_settime");

401

}

402

ret = lower_privileges();

403

if(ret != 0){

404

errno = ret;

405

perror_plus("Failed to lower privileges");

406

}

407

} while(false);

408

409

269

rc = gpgme_data_new_from_fd(&pgp_data, fd);

410

270

if(rc != GPG_ERR_NO_ERROR){

411

271

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

413

273

return false;

414

274

}

415

275

416

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

276

rc = gpgme_op_import(mc.ctx, pgp_data);

417

277

if(rc != GPG_ERR_NO_ERROR){

418

278

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

419

279

gpgme_strsource(rc), gpgme_strerror(rc));

420

280

return false;

421

281

}

422

{

423

gpgme_import_result_t import_result

424

= gpgme_op_import_result(mc->ctx);

425

if((import_result->imported < 1

426

or import_result->not_imported > 0)

427

and import_result->unchanged == 0){

428

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

429

fprintf_plus(stderr,

430

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

431

import_result->considered);

432

fprintf_plus(stderr,

433

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

434

import_result->no_user_id);

435

fprintf_plus(stderr,

436

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

437

import_result->imported);

438

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

439

import_result->imported_rsa);

440

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

441

import_result->unchanged);

442

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

443

import_result->new_user_ids);

444

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

445

import_result->new_sub_keys);

446

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

447

import_result->new_signatures);

448

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

449

import_result->new_revocations);

450

fprintf_plus(stderr,

451

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

452

import_result->secret_read);

453

fprintf_plus(stderr,

454

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

455

import_result->secret_imported);

456

fprintf_plus(stderr,

457

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

458

import_result->secret_unchanged);

459

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

460

import_result->not_imported);

461

for(gpgme_import_status_t import_status

462

= import_result->imports;

463

import_status != NULL;

464

import_status = import_status->next){

465

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

466

import_status->fpr);

467

if(import_status->result != GPG_ERR_NO_ERROR){

468

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

469

gpgme_strsource(import_status->result),

470

gpgme_strerror(import_status->result));

471

}

472

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

473

fprintf_plus(stderr,

474

import_status->status & GPGME_IMPORT_NEW

475

? "The key was new.\n"

476

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

477

fprintf_plus(stderr,

478

import_status->status & GPGME_IMPORT_UID

479

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

480

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

481

fprintf_plus(stderr,

482

import_status->status & GPGME_IMPORT_SIG

483

? "The key contained new signatures.\n"

484

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

485

fprintf_plus(stderr,

486

import_status->status & GPGME_IMPORT_SUBKEY

487

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

488

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

489

fprintf_plus(stderr,

490

import_status->status & GPGME_IMPORT_SECRET

491

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

492

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

493

}

494

return false;

495

}

496

}

497

282

498

ret = close(fd);

283

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

499

284

if(ret == -1){

500

285

perror_plus("close");

501

286

}

538

323

}

539

324

540

325

/* Create new GPGME "context" */

541

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

326

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

542

327

if(rc != GPG_ERR_NO_ERROR){

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

328

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

329

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

330

gpgme_strerror(rc));

545

331

return false;

546

332

}

547

333

556

342

* Decrypt OpenPGP data.

557

343

* Returns -1 on error

558

344

*/

559

__attribute__((nonnull, warn_unused_result))

560

345

static ssize_t pgp_packet_decrypt(const char *cryptotext,

561

346

size_t crypto_size,

562

char **plaintext,

563

mandos_context *mc){

347

char **plaintext){

564

348

gpgme_data_t dh_crypto, dh_plain;

565

349

gpgme_error_t rc;

566

350

ssize_t ret;

583

367

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

584

368

rc = gpgme_data_new(&dh_plain);

585

369

if(rc != GPG_ERR_NO_ERROR){

586

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

370

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

371

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

587

372

gpgme_strsource(rc), gpgme_strerror(rc));

588

373

gpgme_data_release(dh_crypto);

589

374

return -1;

591

376

592

377

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

593

378

data buffer */

594

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

379

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

595

380

if(rc != GPG_ERR_NO_ERROR){

596

381

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

597

382

gpgme_strsource(rc), gpgme_strerror(rc));

598

383

plaintext_length = -1;

599

384

if(debug){

600

385

gpgme_decrypt_result_t result;

601

result = gpgme_op_decrypt_result(mc->ctx);

386

result = gpgme_op_decrypt_result(mc.ctx);

602

387

if(result == NULL){

603

388

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

604

389

} else {

605

if(result->unsupported_algorithm != NULL) {

606

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

607

result->unsupported_algorithm);

608

}

609

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

610

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

390

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

391

result->unsupported_algorithm);

392

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

393

result->wrong_key_usage);

611

394

if(result->file_name != NULL){

612

395

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

613

396

}

614

615

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

616

r = r->next){

397

gpgme_recipient_t recipient;

398

recipient = result->recipients;

399

while(recipient != NULL){

617

400

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

618

gpgme_pubkey_algo_name(r->pubkey_algo));

619

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

401

gpgme_pubkey_algo_name

402

(recipient->pubkey_algo));

403

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

620

404

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

621

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

405

recipient->status == GPG_ERR_NO_SECKEY

406

? "No" : "Yes");

407

recipient = recipient->next;

622

408

}

623

409

}

624

410

}

680

466

return plaintext_length;

681

467

}

682

468

683

__attribute__((warn_unused_result, const))

684

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

685

if(str == NULL)

686

return "(unknown)";

687

return str;

688

}

689

690

__attribute__((warn_unused_result))

691

static const char *safer_gnutls_strerror(int value){

692

const char *ret = gnutls_strerror(value);

693

return safe_string(ret);

469

static const char * safer_gnutls_strerror(int value){

470

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

471

-Wunreachable-code */

472

if(ret == NULL)

473

ret = "(unknown)";

474

return ret;

694

475

}

695

476

696

477

/* GnuTLS log function callback */

697

__attribute__((nonnull))

698

478

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

699

479

const char* string){

700

480

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

701

481

}

702

482

703

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

704

483

static int init_gnutls_global(const char *pubkeyfilename,

705

const char *seckeyfilename,

706

const char *dhparamsfilename,

707

mandos_context *mc){

484

const char *seckeyfilename){

708

485

int ret;

709

486

710

487

if(debug){

711

488

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

712

489

}

713

490

491

ret = gnutls_global_init();

492

if(ret != GNUTLS_E_SUCCESS){

493

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

494

safer_gnutls_strerror(ret));

495

return -1;

496

}

497

714

498

if(debug){

715

499

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

716

500

* - GnuTLS manual

720

504

}

721

505

722

506

/* OpenPGP credentials */

723

ret = gnutls_certificate_allocate_credentials(&mc->cred);

507

ret = gnutls_certificate_allocate_credentials(&mc.cred);

724

508

if(ret != GNUTLS_E_SUCCESS){

725

509

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

726

510

safer_gnutls_strerror(ret));

511

gnutls_global_deinit();

727

512

return -1;

728

513

}

729

514

730

515

if(debug){

731

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

732

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

516

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

517

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

733

518

pubkeyfilename,

734

519

seckeyfilename);

735

520

}

736

521

737

#if GNUTLS_VERSION_NUMBER >= 0x030606

738

ret = gnutls_certificate_set_rawpk_key_file

739

(mc->cred, pubkeyfilename, seckeyfilename,

740

GNUTLS_X509_FMT_PEM, /* format */

741

NULL, /* pass */

742

/* key_usage */

743

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

744

NULL, /* names */

745

0, /* names_length */

746

/* privkey_flags */

747

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

748

0); /* pkcs11_flags */

749

#elif GNUTLS_VERSION_NUMBER < 0x030600

750

522

ret = gnutls_certificate_set_openpgp_key_file

751

(mc->cred, pubkeyfilename, seckeyfilename,

523

(mc.cred, pubkeyfilename, seckeyfilename,

752

524

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

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

755

#endif

756

525

if(ret != GNUTLS_E_SUCCESS){

757

526

fprintf_plus(stderr,

758

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

527

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

759

528

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

760

529

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

761

530

safer_gnutls_strerror(ret));

763

532

}

764

533

765

534

/* GnuTLS server initialization */

766

ret = gnutls_dh_params_init(&mc->dh_params);

535

ret = gnutls_dh_params_init(&mc.dh_params);

767

536

if(ret != GNUTLS_E_SUCCESS){

768

537

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

769

538

" initialization: %s\n",

770

539

safer_gnutls_strerror(ret));

771

540

goto globalfail;

772

541

}

773

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

774

if(dhparamsfilename != NULL){

775

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

776

do {

777

int dhpfile = open(dhparamsfilename, O_RDONLY);

778

if(dhpfile == -1){

779

perror_plus("open");

780

dhparamsfilename = NULL;

781

break;

782

}

783

size_t params_capacity = 0;

784

while(true){

785

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

786

(size_t)params.size,

787

(size_t)params_capacity);

788

if(params_capacity == 0){

789

perror_plus("incbuffer");

790

free(params.data);

791

params.data = NULL;

792

dhparamsfilename = NULL;

793

break;

794

}

795

ssize_t bytes_read = read(dhpfile,

796

params.data + params.size,

797

BUFFER_SIZE);

798

/* EOF */

799

if(bytes_read == 0){

800

break;

801

}

802

/* check bytes_read for failure */

803

if(bytes_read < 0){

804

perror_plus("read");

805

free(params.data);

806

params.data = NULL;

807

dhparamsfilename = NULL;

808

break;

809

}

810

params.size += (unsigned int)bytes_read;

811

}

812

ret = close(dhpfile);

813

if(ret == -1){

814

perror_plus("close");

815

}

816

if(params.data == NULL){

817

dhparamsfilename = NULL;

818

}

819

if(dhparamsfilename == NULL){

820

break;

821

}

822

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

823

GNUTLS_X509_FMT_PEM);

824

if(ret != GNUTLS_E_SUCCESS){

825

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

826

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

827

safer_gnutls_strerror(ret));

828

dhparamsfilename = NULL;

829

}

830

free(params.data);

831

} while(false);

832

}

833

if(dhparamsfilename == NULL){

834

if(mc->dh_bits == 0){

835

#if GNUTLS_VERSION_NUMBER < 0x030600

836

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

837

/* Try to read the private key file */

838

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

839

do {

840

int secfile = open(seckeyfilename, O_RDONLY);

841

if(secfile == -1){

842

perror_plus("open");

843

break;

844

}

845

size_t buffer_capacity = 0;

846

while(true){

847

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

848

(size_t)buffer.size,

849

(size_t)buffer_capacity);

850

if(buffer_capacity == 0){

851

perror_plus("incbuffer");

852

free(buffer.data);

853

buffer.data = NULL;

854

break;

855

}

856

ssize_t bytes_read = read(secfile,

857

buffer.data + buffer.size,

858

BUFFER_SIZE);

859

/* EOF */

860

if(bytes_read == 0){

861

break;

862

}

863

/* check bytes_read for failure */

864

if(bytes_read < 0){

865

perror_plus("read");

866

free(buffer.data);

867

buffer.data = NULL;

868

break;

869

}

870

buffer.size += (unsigned int)bytes_read;

871

}

872

close(secfile);

873

} while(false);

874

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

875

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

876

if(buffer.data != NULL){

877

{

878

gnutls_openpgp_privkey_t privkey = NULL;

879

ret = gnutls_openpgp_privkey_init(&privkey);

880

if(ret != GNUTLS_E_SUCCESS){

881

fprintf_plus(stderr, "Error initializing OpenPGP key"

882

" structure: %s",

883

safer_gnutls_strerror(ret));

884

free(buffer.data);

885

buffer.data = NULL;

886

} else {

887

ret = gnutls_openpgp_privkey_import

888

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

889

if(ret != GNUTLS_E_SUCCESS){

890

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

891

safer_gnutls_strerror(ret));

892

privkey = NULL;

893

}

894

free(buffer.data);

895

buffer.data = NULL;

896

if(privkey != NULL){

897

/* Use private key to suggest an appropriate

898

sec_param */

899

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

900

gnutls_openpgp_privkey_deinit(privkey);

901

if(debug){

902

fprintf_plus(stderr, "This OpenPGP key implies using"

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)));

906

}

907

}

908

}

909

}

910

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

911

/* Err on the side of caution */

912

sec_param = GNUTLS_SEC_PARAM_ULTRA;

913

if(debug){

914

fprintf_plus(stderr, "Falling back to security parameter"

915

" \"%s\"\n",

916

safe_string(gnutls_sec_param_get_name

917

(sec_param)));

918

}

919

}

920

}

921

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

922

if(uret != 0){

923

mc->dh_bits = uret;

924

if(debug){

925

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

926

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

927

safe_string(gnutls_sec_param_get_name

928

(sec_param)),

929

mc->dh_bits);

930

}

931

} else {

932

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

933

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

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)),

936

safer_gnutls_strerror(ret));

937

goto globalfail;

938

}

939

#endif

940

} else { /* dh_bits != 0 */

941

if(debug){

942

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

943

mc->dh_bits);

944

}

945

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

946

if(ret != GNUTLS_E_SUCCESS){

947

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

948

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

949

safer_gnutls_strerror(ret));

950

goto globalfail;

951

}

952

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

953

}

954

}

542

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

543

if(ret != GNUTLS_E_SUCCESS){

544

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

545

safer_gnutls_strerror(ret));

546

goto globalfail;

547

}

548

549

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

955

550

956

551

return 0;

957

552

958

553

globalfail:

959

554

960

gnutls_certificate_free_credentials(mc->cred);

961

gnutls_dh_params_deinit(mc->dh_params);

555

gnutls_certificate_free_credentials(mc.cred);

556

gnutls_global_deinit();

557

gnutls_dh_params_deinit(mc.dh_params);

962

558

return -1;

963

559

}

964

560

965

__attribute__((nonnull, warn_unused_result))

966

static int init_gnutls_session(gnutls_session_t *session,

967

mandos_context *mc){

561

static int init_gnutls_session(gnutls_session_t *session){

968

562

int ret;

969

563

/* GnuTLS session creation */

970

564

do {

971

ret = gnutls_init(session, (GNUTLS_SERVER

972

#if GNUTLS_VERSION_NUMBER >= 0x030506

973

| GNUTLS_NO_TICKETS

974

#endif

975

#if GNUTLS_VERSION_NUMBER >= 0x030606

976

| GNUTLS_ENABLE_RAWPK

977

#endif

978

));

565

ret = gnutls_init(session, GNUTLS_SERVER);

979

566

if(quit_now){

980

567

return -1;

981

568

}

989

576

{

990

577

const char *err;

991

578

do {

992

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

579

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

993

580

if(quit_now){

994

581

gnutls_deinit(*session);

995

582

return -1;

1006

593

1007

594

do {

1008

595

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1009

mc->cred);

596

mc.cred);

1010

597

if(quit_now){

1011

598

gnutls_deinit(*session);

1012

599

return -1;

1022

609

/* ignore client certificate if any. */

1023

610

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1024

611

612

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

613

1025

614

return 0;

1026

615

}

1027

616

1029

618

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

1030

619

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

1031

620

1032

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

1033

__attribute__((nonnull, warn_unused_result))

1034

static bool add_delete_local_route(const bool add,

1035

const char *address,

1036

AvahiIfIndex if_index){

1037

int ret;

1038

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

1039

char add_arg[] = "add";

1040

char delete_arg[] = "delete";

1041

char debug_flag[] = "--debug";

1042

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1043

if(pluginhelperdir == NULL){

1044

if(debug){

1045

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1046

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

1047

}

1048

return false;

1049

}

1050

1051

char interface[IF_NAMESIZE];

1052

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

1053

perror_plus("if_indextoname");

1054

return false;

1055

}

1056

1057

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

1058

if(devnull == -1){

1059

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

1060

return false;

1061

}

1062

pid_t pid = fork();

1063

if(pid == 0){

1064

/* Child */

1065

/* Raise privileges */

1066

errno = raise_privileges_permanently();

1067

if(errno != 0){

1068

perror_plus("Failed to raise privileges");

1069

/* _exit(EX_NOPERM); */

1070

} else {

1071

/* Set group */

1072

errno = 0;

1073

ret = setgid(0);

1074

if(ret == -1){

1075

perror_plus("setgid");

1076

close(devnull);

1077

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

close(devnull);

1085

_exit(EX_NOPERM);

1086

}

1087

}

1088

ret = dup2(devnull, STDIN_FILENO);

1089

if(ret == -1){

1090

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

1091

close(devnull);

1092

_exit(EX_OSERR);

1093

}

1094

ret = close(devnull);

1095

if(ret == -1){

1096

perror_plus("close");

1097

}

1098

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1099

if(ret == -1){

1100

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

1101

_exit(EX_OSERR);

1102

}

1103

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

1104

O_RDONLY

1105

| O_DIRECTORY

1106

| O_PATH

1107

| O_CLOEXEC));

1108

if(helperdir_fd == -1){

1109

perror_plus("open");

1110

_exit(EX_UNAVAILABLE);

1111

}

1112

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

1113

helper, O_RDONLY));

1114

if(helper_fd == -1){

1115

perror_plus("openat");

1116

close(helperdir_fd);

1117

_exit(EX_UNAVAILABLE);

1118

}

1119

close(helperdir_fd);

1120

#ifdef __GNUC__

1121

#pragma GCC diagnostic push

1122

#pragma GCC diagnostic ignored "-Wcast-qual"

1123

#endif

1124

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

1125

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

1126

interface, debug ? debug_flag : NULL, NULL },

1127

environ) == -1){

1128

#ifdef __GNUC__

1129

#pragma GCC diagnostic pop

1130

#endif

1131

perror_plus("fexecve");

1132

_exit(EXIT_FAILURE);

1133

}

1134

}

1135

if(pid == -1){

1136

perror_plus("fork");

1137

close(devnull);

1138

return false;

1139

}

1140

ret = close(devnull);

1141

if(ret == -1){

1142

perror_plus("close");

1143

}

1144

int status;

1145

pid_t pret = -1;

1146

errno = 0;

1147

do {

1148

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

1149

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

1150

int errno_raising = 0;

1151

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

1152

errno_raising = errno;

1153

perror_plus("Failed to raise privileges in order to"

1154

" kill helper program");

1155

}

1156

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

1157

perror_plus("kill");

1158

}

1159

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

1160

perror_plus("Failed to lower privileges after killing"

1161

" helper program");

1162

}

1163

return false;

1164

}

1165

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

1166

if(pret == -1){

1167

perror_plus("waitpid");

1168

return false;

1169

}

1170

if(WIFEXITED(status)){

1171

if(WEXITSTATUS(status) != 0){

1172

fprintf_plus(stderr, "Error: iprouteadddel exited"

1173

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

1174

return false;

1175

}

1176

return true;

1177

}

1178

if(WIFSIGNALED(status)){

1179

fprintf_plus(stderr, "Error: iprouteadddel died by"

1180

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

1181

return false;

1182

}

1183

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

1184

return false;

1185

}

1186

1187

__attribute__((nonnull, warn_unused_result))

1188

static bool add_local_route(const char *address,

1189

AvahiIfIndex if_index){

1190

if(debug){

1191

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

1192

}

1193

return add_delete_local_route(true, address, if_index);

1194

}

1195

1196

__attribute__((nonnull, warn_unused_result))

1197

static bool delete_local_route(const char *address,

1198

AvahiIfIndex if_index){

1199

if(debug){

1200

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

1201

}

1202

return add_delete_local_route(false, address, if_index);

1203

}

1204

1205

621

/* Called when a Mandos server is found */

1206

__attribute__((nonnull, warn_unused_result))

1207

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

622

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

1208

623

AvahiIfIndex if_index,

1209

int af, mandos_context *mc){

624

int af){

1210

625

int ret, tcp_sd = -1;

1211

626

ssize_t sret;

1212

struct sockaddr_storage to;

627

union {

628

struct sockaddr_in in;

629

struct sockaddr_in6 in6;

630

} to;

1213

631

char *buffer = NULL;

1214

632

char *decrypted_buffer = NULL;

1215

633

size_t buffer_length = 0;

1218

636

int retval = -1;

1219

637

gnutls_session_t session;

1220

638

int pf; /* Protocol family */

1221

bool route_added = false;

1222

639

1223

640

errno = 0;

1224

641

1240

657

return -1;

1241

658

}

1242

659

1243

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

1244

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

1245

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

1246

bool match = false;

1247

{

1248

char *interface = NULL;

1249

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

1250

mc->interfaces_size,

1251

interface))){

1252

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

1253

match = true;

1254

break;

1255

}

1256

}

1257

}

1258

if(not match){

1259

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

1260

connect to the server */

1261

if(debug){

1262

char interface[IF_NAMESIZE];

1263

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

1264

perror_plus("if_indextoname");

1265

} else {

1266

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

1267

" \"%s\"\n",

1268

if_indextoname((unsigned int)if_index,

1269

interface));

1270

}

1271

}

1272

return -1;

1273

}

1274

}

1275

1276

ret = init_gnutls_session(&session, mc);

660

ret = init_gnutls_session(&session);

1277

661

if(ret != 0){

1278

662

return -1;

1279

663

}

1280

664

1281

665

if(debug){

1282

666

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

1283

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

667

PRIu16 "\n", ip, port);

1284

668

}

1285

669

1286

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

670

tcp_sd = socket(pf, SOCK_STREAM, 0);

1287

671

if(tcp_sd < 0){

1288

672

int e = errno;

1289

673

perror_plus("socket");

1296

680

goto mandos_end;

1297

681

}

1298

682

683

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

1299

684

if(af == AF_INET6){

1300

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

1301

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

1302

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

685

to.in6.sin6_family = (sa_family_t)af;

686

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

1303

687

} else { /* IPv4 */

1304

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

1305

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

1306

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

688

to.in.sin_family = (sa_family_t)af;

689

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

1307

690

}

1308

691

if(ret < 0 ){

1309

692

int e = errno;

1318

701

goto mandos_end;

1319

702

}

1320

703

if(af == AF_INET6){

1321

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

1322

if(IN6_IS_ADDR_LINKLOCAL

1323

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

704

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

705

-Wconversion and

706

-Wunreachable-code */

707

708

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

709

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

710

-Wunreachable-code*/

1324

711

if(if_index == AVAHI_IF_UNSPEC){

1325

712

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

1326

713

" incomplete without a network interface\n");

1328

715

goto mandos_end;

1329

716

}

1330

717

/* Set the network interface number as scope */

1331

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

718

to.in6.sin6_scope_id = (uint32_t)if_index;

1332

719

}

1333

720

} else {

1334

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

721

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

722

-Wconversion and

723

-Wunreachable-code */

1335

724

}

1336

725

1337

726

if(quit_now){

1345

734

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

1346

735

perror_plus("if_indextoname");

1347

736

} else {

1348

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

1349

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

737

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

738

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

1350

739

}

1351

740

} else {

1352

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

1353

ip, (uintmax_t)port);

741

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

742

ip, port);

1354

743

}

1355

744

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1356

745

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1357

if(af == AF_INET6){

1358

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

1359

sizeof(struct sockaddr_in6),

1360

addrstr, sizeof(addrstr), NULL, 0,

1361

NI_NUMERICHOST);

1362

} else {

1363

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

1364

sizeof(struct sockaddr_in),

1365

addrstr, sizeof(addrstr), NULL, 0,

1366

NI_NUMERICHOST);

1367

}

1368

if(ret == EAI_SYSTEM){

1369

perror_plus("getnameinfo");

1370

} else if(ret != 0) {

1371

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

1372

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

1373

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

1374

}

1375

}

1376

1377

if(quit_now){

1378

errno = EINTR;

1379

goto mandos_end;

1380

}

1381

1382

while(true){

1383

if(af == AF_INET6){

1384

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

1385

sizeof(struct sockaddr_in6));

1386

} else {

1387

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

1388

sizeof(struct sockaddr_in));

1389

}

1390

if(ret < 0){

1391

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

1392

and if_index != AVAHI_IF_UNSPEC

1393

and connect_to == NULL

1394

and not route_added and

1395

((af == AF_INET6 and not

1396

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1397

&to)->sin6_addr)))

1398

or (af == AF_INET and

1399

/* Not a a IPv4LL address */

1400

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

1401

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

1402

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

1403

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

1404

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

1405

connect to a Mandos server announced by Avahi on a server

1406

host with a global address. Work around this by retrying

1407

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

1408

1409

Avahi bug reference:

1410

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

1411

https://bugs.debian.org/587961

1412

*/

1413

if(debug){

1414

fprintf_plus(stderr, "Mandos server unreachable, trying"

1415

" direct route\n");

1416

}

1417

int e = errno;

1418

route_added = add_local_route(ip, if_index);

1419

if(route_added){

1420

continue;

1421

}

1422

errno = e;

1423

}

1424

if(errno != ECONNREFUSED or debug){

1425

int e = errno;

1426

perror_plus("connect");

1427

errno = e;

1428

}

1429

goto mandos_end;

1430

}

1431

1432

if(quit_now){

1433

errno = EINTR;

1434

goto mandos_end;

1435

}

1436

break;

746

const char *pcret;

747

if(af == AF_INET6){

748

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

749

sizeof(addrstr));

750

} else {

751

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

752

sizeof(addrstr));

753

}

754

if(pcret == NULL){

755

perror_plus("inet_ntop");

756

} else {

757

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

758

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

759

}

760

}

761

}

762

763

if(quit_now){

764

errno = EINTR;

765

goto mandos_end;

766

}

767

768

if(af == AF_INET6){

769

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

770

} else {

771

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

772

}

773

if(ret < 0){

774

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

775

int e = errno;

776

perror_plus("connect");

777

errno = e;

778

}

779

goto mandos_end;

780

}

781

782

if(quit_now){

783

errno = EINTR;

784

goto mandos_end;

1437

785

}

1438

786

1439

787

const char *out = mandos_protocol_version;

1590

938

if(buffer_length > 0){

1591

939

ssize_t decrypted_buffer_size;

1592

940

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1593

&decrypted_buffer, mc);

941

&decrypted_buffer);

1594

942

if(decrypted_buffer_size >= 0){

1595

943

1596

clearerr(stdout);

1597

944

written = 0;

1598

945

while(written < (size_t) decrypted_buffer_size){

1599

946

if(quit_now){

1615

962

}

1616

963

written += (size_t)ret;

1617

964

}

1618

ret = fflush(stdout);

1619

if(ret != 0){

1620

int e = errno;

1621

if(debug){

1622

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

1623

strerror(errno));

1624

}

1625

errno = e;

1626

goto mandos_end;

1627

}

1628

965

retval = 0;

1629

966

}

1630

967

}

1633

970

1634

971

mandos_end:

1635

972

{

1636

if(route_added){

1637

if(not delete_local_route(ip, if_index)){

1638

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

1639

" interface %d", ip, if_index);

1640

}

1641

}

1642

973

int e = errno;

1643

974

free(decrypted_buffer);

1644

975

free(buffer);

1645

976

if(tcp_sd >= 0){

1646

ret = close(tcp_sd);

977

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

1647

978

}

1648

979

if(ret == -1){

1649

980

if(e == 0){

1674

1005

AVAHI_GCC_UNUSED AvahiStringList *txt,

1675

1006

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1676

1007

flags,

1677

void *mc){

1678

if(r == NULL){

1679

return;

1680

}

1008

AVAHI_GCC_UNUSED void* userdata){

1009

assert(r);

1681

1010

1682

1011

/* Called whenever a service has been resolved successfully or

1683

1012

timed out */

1684

1013

1685

1014

if(quit_now){

1686

avahi_s_service_resolver_free(r);

1687

1015

return;

1688

1016

}

1689

1017

1693

1021

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

1694

1022

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

1695

1023

domain,

1696

avahi_strerror(avahi_server_errno

1697

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

1024

avahi_strerror(avahi_server_errno(mc.server)));

1698

1025

break;

1699

1026

1700

1027

case AVAHI_RESOLVER_FOUND:

1706

1033

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

1707

1034

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

1708

1035

}

1709

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

1710

interface,

1711

avahi_proto_to_af(proto),

1712

mc);

1036

int ret = start_mandos_communication(ip, port, interface,

1037

avahi_proto_to_af(proto));

1713

1038

if(ret == 0){

1714

avahi_simple_poll_quit(simple_poll);

1039

avahi_simple_poll_quit(mc.simple_poll);

1715

1040

} else {

1716

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

1717

avahi_proto_to_af(proto),

1718

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

1041

if(not add_server(ip, port, interface,

1042

avahi_proto_to_af(proto))){

1719

1043

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

1720

1044

" list\n", name);

1721

1045

}

1734

1058

const char *domain,

1735

1059

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1736

1060

flags,

1737

void *mc){

1738

if(b == NULL){

1739

return;

1740

}

1061

AVAHI_GCC_UNUSED void* userdata){

1062

assert(b);

1741

1063

1742

1064

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

1743

1065

is removed from the LAN */

1751

1073

case AVAHI_BROWSER_FAILURE:

1752

1074

1753

1075

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

1754

avahi_strerror(avahi_server_errno

1755

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

1756

avahi_simple_poll_quit(simple_poll);

1076

avahi_strerror(avahi_server_errno(mc.server)));

1077

avahi_simple_poll_quit(mc.simple_poll);

1757

1078

return;

1758

1079

1759

1080

case AVAHI_BROWSER_NEW:

1762

1083

the callback function is called the Avahi server will free the

1763

1084

resolver for us. */

1764

1085

1765

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

1766

interface, protocol, name, type,

1767

domain, protocol, 0,

1768

resolve_callback, mc) == NULL)

1086

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

1087

name, type, domain, protocol, 0,

1088

resolve_callback, NULL) == NULL)

1769

1089

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

1770

1090

" %s\n", name,

1771

avahi_strerror(avahi_server_errno

1772

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

1091

avahi_strerror(avahi_server_errno(mc.server)));

1773

1092

break;

1774

1093

1775

1094

case AVAHI_BROWSER_REMOVE:

1794

1113

signal_received = sig;

1795

1114

int old_errno = errno;

1796

1115

/* set main loop to exit */

1797

if(simple_poll != NULL){

1798

avahi_simple_poll_quit(simple_poll);

1116

if(mc.simple_poll != NULL){

1117

avahi_simple_poll_quit(mc.simple_poll);

1799

1118

}

1800

1119

errno = old_errno;

1801

1120

}

1802

1121

1803

__attribute__((nonnull, warn_unused_result))

1804

1122

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

1805

1123

int ret;

1806

int old_errno;

1807

1124

1808

1125

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

1809

1126

if(s < 0){

1810

old_errno = errno;

1811

1127

perror_plus("socket");

1812

errno = old_errno;

1813

1128

return false;

1814

1129

}

1815

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

1816

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

1130

strcpy(ifr->ifr_name, ifname);

1817

1131

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1818

1132

if(ret == -1){

1819

1133

if(debug){

1820

old_errno = errno;

1821

1134

perror_plus("ioctl SIOCGIFFLAGS");

1822

errno = old_errno;

1823

}

1824

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

1825

old_errno = errno;

1826

perror_plus("close");

1827

errno = old_errno;

1828

1135

}

1829

1136

return false;

1830

1137

}

1831

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

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1836

1138

return true;

1837

1139

}

1838

1140

1839

__attribute__((nonnull, warn_unused_result))

1840

1141

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

1841

1142

1842

1143

/* Reject the loopback device */

1884

1185

* corresponds to an acceptable network device.

1885

1186

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

1886

1187

*/

1887

__attribute__((nonnull, warn_unused_result))

1888

1188

int good_interface(const struct dirent *if_entry){

1889

1189

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

1890

1190

return 0;

1906

1206

}

1907

1207

1908

1208

/*

1909

* This function determines if a network interface is up.

1910

*/

1911

__attribute__((nonnull, warn_unused_result))

1912

bool interface_is_up(const char *interface){

1913

struct ifreq ifr;

1914

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

1915

if(debug){

1916

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

1917

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

1918

}

1919

return false;

1920

}

1921

1922

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

1923

}

1924

1925

/*

1926

* This function determines if a network interface is running

1927

*/

1928

__attribute__((nonnull, warn_unused_result))

1929

bool interface_is_running(const char *interface){

1930

struct ifreq ifr;

1931

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

1932

if(debug){

1933

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

1934

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

1935

}

1936

return false;

1937

}

1938

1939

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

1940

}

1941

1942

__attribute__((nonnull, pure, warn_unused_result))

1209

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

1210

* corresponds to an acceptable network device which is up.

1211

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

1212

*/

1213

int up_interface(const struct dirent *if_entry){

1214

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

1215

return 0;

1216

}

1217

1218

struct ifreq ifr;

1219

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

1220

if(debug){

1221

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

1222

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

1223

}

1224

return 0;

1225

}

1226

1227

/* Reject down interfaces */

1228

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

1229

if(debug){

1230

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

1231

if_entry->d_name);

1232

}

1233

return 0;

1234

}

1235

1236

/* Reject non-running interfaces */

1237

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

1238

if(debug){

1239

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

1240

if_entry->d_name);

1241

}

1242

return 0;

1243

}

1244

1245

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

1246

return 0;

1247

}

1248

return 1;

1249

}

1250

1943

1251

int notdotentries(const struct dirent *direntry){

1944

1252

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

1945

1253

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

1952

1260

}

1953

1261

1954

1262

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

1955

__attribute__((nonnull, warn_unused_result))

1956

1263

int runnable_hook(const struct dirent *direntry){

1957

1264

int ret;

1958

1265

size_t sret;

1966

1273

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

1967

1274

"abcdefghijklmnopqrstuvwxyz"

1968

1275

"0123456789"

1969

"_.-");

1276

"_-");

1970

1277

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

1971

1278

/* Contains non-allowed characters */

1972

1279

if(debug){

1976

1283

return 0;

1977

1284

}

1978

1285

1979

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

1286

char *fullname = NULL;

1287

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

1288

if(ret < 0){

1289

perror_plus("asprintf");

1290

return 0;

1291

}

1292

1293

ret = stat(fullname, &st);

1980

1294

if(ret == -1){

1981

1295

if(debug){

1982

1296

perror_plus("Could not stat hook");

2006

1320

return 1;

2007

1321

}

2008

1322

2009

__attribute__((nonnull, warn_unused_result))

2010

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2011

mandos_context *mc){

1323

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2012

1324

int ret;

2013

1325

struct timespec now;

2014

1326

struct timespec waited_time;

2015

1327

intmax_t block_time;

2016

1328

2017

1329

while(true){

2018

if(mc->current_server == NULL){

2019

if(debug){

1330

if(mc.current_server == NULL){

1331

if (debug){

2020

1332

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

2021

1333

" No timeout!\n");

2022

1334

}

2023

1335

ret = avahi_simple_poll_iterate(s, -1);

2024

1336

} else {

2025

if(debug){

1337

if (debug){

2026

1338

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

2027

1339

" it, or wait\n");

2028

1340

}

2035

1347

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

2036

1348

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

2037

1349

waited_time.tv_sec = (now.tv_sec

2038

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

1350

- mc.current_server->last_seen.tv_sec);

2039

1351

waited_time.tv_nsec = (now.tv_nsec

2040

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

1352

- mc.current_server->last_seen.tv_nsec);

2041

1353

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

2042

1354

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

2043

1355

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

2045

1357

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

2046

1358

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

2047

1359

2048

if(debug){

1360

if (debug){

2049

1361

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

2050

1362

block_time);

2051

1363

}

2052

1364

2053

1365

if(block_time <= 0){

2054

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

2055

mc->current_server->port,

2056

mc->current_server->if_index,

2057

mc->current_server->af, mc);

1366

ret = start_mandos_communication(mc.current_server->ip,

1367

mc.current_server->port,

1368

mc.current_server->if_index,

1369

mc.current_server->af);

2058

1370

if(ret == 0){

2059

avahi_simple_poll_quit(s);

1371

avahi_simple_poll_quit(mc.simple_poll);

2060

1372

return 0;

2061

1373

}

2062

1374

ret = clock_gettime(CLOCK_MONOTONIC,

2063

&mc->current_server->last_seen);

1375

&mc.current_server->last_seen);

2064

1376

if(ret == -1){

2065

1377

perror_plus("clock_gettime");

2066

1378

return -1;

2067

1379

}

2068

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

1380

mc.current_server = mc.current_server->next;

2069

1381

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

2070

1382

servers, but don't block */

2071

1383

}

2073

1385

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

2074

1386

}

2075

1387

if(ret != 0){

2076

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

1388

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

2077

1389

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

2078

1390

}

2079

1391

}

2080

1392

}

2081

1393

}

2082

1394

2083

__attribute__((nonnull))

2084

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

1395

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

1396

int raise_privileges(void){

1397

int old_errno = errno;

1398

int ret_errno = 0;

1399

errno = 0;

1400

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

1401

perror_plus("seteuid");

1402

}

1403

ret_errno = errno;

1404

errno = old_errno;

1405

return ret_errno;

1406

}

1407

1408

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

1409

int raise_privileges_permanently(void){

1410

int old_errno = errno;

1411

int ret_errno = raise_privileges();

1412

if(ret_errno != 0){

1413

errno = old_errno;

1414

return ret_errno;

1415

}

1416

errno = 0;

1417

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

1418

perror_plus("seteuid");

1419

}

1420

ret_errno = errno;

1421

errno = old_errno;

1422

return ret_errno;

1423

}

1424

1425

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

1426

int lower_privileges(void){

1427

int old_errno = errno;

1428

int ret_errno = 0;

1429

errno = 0;

1430

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

1431

perror_plus("seteuid");

1432

}

1433

ret_errno = errno;

1434

errno = old_errno;

1435

return ret_errno;

1436

}

1437

1438

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

2085

1439

const float delay){

2086

struct dirent **direntries = NULL;

2087

if(hookdir_fd == -1){

2088

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2089

| O_CLOEXEC);

2090

if(hookdir_fd == -1){

2091

if(errno == ENOENT){

2092

if(debug){

2093

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

2094

" found\n", hookdir);

2095

}

2096

} else {

2097

perror_plus("open");

2098

}

2099

return;

2100

}

2101

}

2102

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

2103

if(devnull == -1){

2104

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

2105

return;

2106

}

2107

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

2108

runnable_hook, alphasort);

1440

struct dirent **direntries;

1441

struct dirent *direntry;

1442

int ret;

1443

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

1444

alphasort);

2109

1445

if(numhooks == -1){

2110

1446

perror_plus("scandir");

2111

close(devnull);

2112

return;

2113

}

2114

struct dirent *direntry;

2115

int ret;

2116

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

2117

direntry = direntries[i];

2118

if(debug){

2119

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

2120

direntry->d_name);

2121

}

2122

pid_t hook_pid = fork();

2123

if(hook_pid == 0){

2124

/* Child */

2125

/* Raise privileges */

2126

errno = raise_privileges_permanently();

2127

if(errno != 0){

2128

perror_plus("Failed to raise privileges");

2129

_exit(EX_NOPERM);

2130

}

2131

/* Set group */

2132

errno = 0;

2133

ret = setgid(0);

2134

if(ret == -1){

2135

perror_plus("setgid");

2136

_exit(EX_NOPERM);

2137

}

2138

/* Reset supplementary groups */

2139

errno = 0;

2140

ret = setgroups(0, NULL);

2141

if(ret == -1){

2142

perror_plus("setgroups");

2143

_exit(EX_NOPERM);

2144

}

2145

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

2146

if(ret == -1){

2147

perror_plus("setenv");

2148

_exit(EX_OSERR);

2149

}

2150

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

2151

if(ret == -1){

2152

perror_plus("setenv");

2153

_exit(EX_OSERR);

2154

}

2155

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

2156

if(ret == -1){

2157

perror_plus("setenv");

2158

_exit(EX_OSERR);

2159

}

2160

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

2161

if(ret == -1){

2162

perror_plus("setenv");

2163

_exit(EX_OSERR);

2164

}

2165

char *delaystring;

2166

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

2167

if(ret == -1){

1447

} else {

1448

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

1449

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

1450

direntry = direntries[i];

1451

char *fullname = NULL;

1452

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

1453

if(ret < 0){

2168

1454

perror_plus("asprintf");

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

if(ret == -1){

1455

continue;

1456

}

1457

if(debug){

1458

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

1459

direntry->d_name);

1460

}

1461

pid_t hook_pid = fork();

1462

if(hook_pid == 0){

1463

/* Child */

1464

/* Raise privileges */

1465

raise_privileges_permanently();

1466

/* Set group */

1467

errno = 0;

1468

ret = setgid(0);

1469

if(ret == -1){

1470

perror_plus("setgid");

1471

}

1472

/* Reset supplementary groups */

1473

errno = 0;

1474

ret = setgroups(0, NULL);

1475

if(ret == -1){

1476

perror_plus("setgroups");

1477

}

1478

dup2(devnull, STDIN_FILENO);

1479

close(devnull);

1480

dup2(STDERR_FILENO, STDOUT_FILENO);

1481

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

1482

if(ret == -1){

1483

perror_plus("setenv");

1484

_exit(EX_OSERR);

1485

}

1486

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

1487

if(ret == -1){

1488

perror_plus("setenv");

1489

_exit(EX_OSERR);

1490

}

1491

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

1492

if(ret == -1){

1493

perror_plus("setenv");

1494

_exit(EX_OSERR);

1495

}

1496

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

1497

if(ret == -1){

1498

perror_plus("setenv");

1499

_exit(EX_OSERR);

1500

}

1501

char *delaystring;

1502

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

1503

if(ret == -1){

1504

perror_plus("asprintf");

1505

_exit(EX_OSERR);

1506

}

1507

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

1508

if(ret == -1){

1509

free(delaystring);

1510

perror_plus("setenv");

1511

_exit(EX_OSERR);

1512

}

2173

1513

free(delaystring);

2174

perror_plus("setenv");

2175

_exit(EX_OSERR);

2176

}

2177

free(delaystring);

2178

if(connect_to != NULL){

2179

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

2180

if(ret == -1){

2181

perror_plus("setenv");

2182

_exit(EX_OSERR);

2183

}

2184

}

2185

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

2186

direntry->d_name,

2187

O_RDONLY));

2188

if(hook_fd == -1){

2189

perror_plus("openat");

2190

_exit(EXIT_FAILURE);

2191

}

2192

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

2193

perror_plus("close");

2194

_exit(EXIT_FAILURE);

2195

}

2196

ret = dup2(devnull, STDIN_FILENO);

2197

if(ret == -1){

2198

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

2199

_exit(EX_OSERR);

2200

}

2201

ret = close(devnull);

2202

if(ret == -1){

2203

perror_plus("close");

2204

_exit(EX_OSERR);

2205

}

2206

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2207

if(ret == -1){

2208

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

2209

_exit(EX_OSERR);

2210

}

2211

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

2212

environ) == -1){

2213

perror_plus("fexecve");

2214

_exit(EXIT_FAILURE);

2215

}

2216

} else {

2217

if(hook_pid == -1){

2218

perror_plus("fork");

2219

free(direntry);

2220

continue;

2221

}

2222

int status;

2223

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

2224

perror_plus("waitpid");

2225

free(direntry);

2226

continue;

2227

}

2228

if(WIFEXITED(status)){

2229

if(WEXITSTATUS(status) != 0){

2230

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

2231

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

2232

WEXITSTATUS(status));

2233

free(direntry);

2234

continue;

2235

}

2236

} else if(WIFSIGNALED(status)){

2237

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

2238

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

2239

WTERMSIG(status));

2240

free(direntry);

2241

continue;

1514

if(connect_to != NULL){

1515

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

1516

if(ret == -1){

1517

perror_plus("setenv");

1518

_exit(EX_OSERR);

1519

}

1520

}

1521

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

1522

perror_plus("execl");

1523

_exit(EXIT_FAILURE);

1524

}

2242

1525

} else {

2243

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

2244

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

2245

free(direntry);

2246

continue;

2247

}

2248

}

2249

if(debug){

2250

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

2251

direntry->d_name);

2252

}

2253

free(direntry);

2254

}

2255

free(direntries);

2256

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

2257

perror_plus("close");

2258

} else {

2259

hookdir_fd = -1;

2260

}

2261

close(devnull);

1526

int status;

1527

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

1528

perror_plus("waitpid");

1529

free(fullname);

1530

continue;

1531

}

1532

if(WIFEXITED(status)){

1533

if(WEXITSTATUS(status) != 0){

1534

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

1535

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

1536

WEXITSTATUS(status));

1537

free(fullname);

1538

continue;

1539

}

1540

} else if(WIFSIGNALED(status)){

1541

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

1542

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

1543

WTERMSIG(status));

1544

free(fullname);

1545

continue;

1546

} else {

1547

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

1548

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

1549

free(fullname);

1550

continue;

1551

}

1552

}

1553

free(fullname);

1554

if(debug){

1555

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

1556

direntry->d_name);

1557

}

1558

}

1559

close(devnull);

1560

}

1561

return true;

2262

1562

}

2263

1563

2264

__attribute__((nonnull, warn_unused_result))

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

1564

int bring_up_interface(const char * const interface, const float delay){

1565

int sd = -1;

2268

1566

int ret;

2269

1567

struct ifreq network;

2270

unsigned int if_index = if_nametoindex(interface);

1568

AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);

2271

1569

if(if_index == 0){

2272

1570

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

2273

errno = old_errno;

2274

return ENXIO;

1571

return EX_UNAVAILABLE;

2275

1572

}

2276

1573

2277

1574

if(quit_now){

2278

errno = old_errno;

2279

1575

return EINTR;

2280

1576

}

2281

1577

2282

if(not interface_is_up(interface)){

2283

int ret_errno = 0;

2284

int ioctl_errno = 0;

2285

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

2286

ret_errno = errno;

2287

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

2288

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

2289

errno = old_errno;

2290

return ret_errno;

2291

}

2292

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

2293

2294

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

2295

if(sd == -1){

2296

ret_errno = errno;

2297

perror_plus("socket");

2298

errno = old_errno;

2299

return ret_errno;

2300

}

2301

2302

if(quit_now){

2303

ret = close(sd);

2304

if(ret == -1){

2305

perror_plus("close");

2306

}

2307

errno = old_errno;

2308

return EINTR;

2309

}

2310

2311

if(debug){

2312

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

2313

interface);

2314

}

2315

2316

/* Raise privileges */

2317

ret_errno = raise_privileges();

2318

if(ret_errno != 0){

2319

errno = ret_errno;

2320

perror_plus("Failed to raise privileges");

2321

}

2322

2323

#ifdef __linux__

2324

int ret_linux;

2325

bool restore_loglevel = false;

2326

if(ret_errno == 0){

2327

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2328

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

2329

ret_linux = klogctl(8, NULL, 5);

2330

if(ret_linux == -1){

2331

perror_plus("klogctl");

2332

} else {

2333

restore_loglevel = true;

2334

}

2335

}

2336

#endif /* __linux__ */

2337

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

2338

ioctl_errno = errno;

2339

#ifdef __linux__

2340

if(restore_loglevel){

2341

ret_linux = klogctl(7, NULL, 0);

2342

if(ret_linux == -1){

2343

perror_plus("klogctl");

2344

}

2345

}

2346

#endif /* __linux__ */

2347

2348

/* If raise_privileges() succeeded above */

2349

if(ret_errno == 0){

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

2357

2358

/* Close the socket */

2359

ret = close(sd);

1578

/* Re-raise priviliges */

1579

raise_privileges();

1580

1581

#ifdef __linux__

1582

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1583

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

1584

ret = klogctl(8, NULL, 5);

1585

bool restore_loglevel = true;

1586

if(ret == -1){

1587

restore_loglevel = false;

1588

perror_plus("klogctl");

1589

}

1590

#endif /* __linux__ */

1591

1592

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1593

if(sd < 0){

1594

perror_plus("socket");

1595

#ifdef __linux__

1596

if(restore_loglevel){

1597

ret = klogctl(7, NULL, 0);

1598

if(ret == -1){

1599

perror_plus("klogctl");

1600

}

1601

}

1602

#endif /* __linux__ */

1603

/* Lower privileges */

1604

lower_privileges();

1605

return EX_OSERR;

1606

;

1607

}

1608

strcpy(network.ifr_name, interface);

1609

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

1610

if(ret == -1){

1611

perror_plus("ioctl SIOCGIFFLAGS");

1612

#ifdef __linux__

1613

if(restore_loglevel){

1614

ret = klogctl(7, NULL, 0);

1615

if(ret == -1){

1616

perror_plus("klogctl");

1617

}

1618

}

1619

#endif /* __linux__ */

1620

/* Lower privileges */

1621

lower_privileges();

1622

return EX_OSERR;

1623

}

1624

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

1625

network.ifr_flags |= IFF_UP;

1626

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

2360

1627

if(ret == -1){

2361

perror_plus("close");

2362

}

2363

2364

if(ret_setflags == -1){

2365

errno = ioctl_errno;

2366

1628

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2367

errno = old_errno;

2368

return ioctl_errno;

1629

#ifdef __linux__

1630

if(restore_loglevel){

1631

ret = klogctl(7, NULL, 0);

1632

if(ret == -1){

1633

perror_plus("klogctl");

1634

}

1635

}

1636

#endif /* __linux__ */

1637

/* Lower privileges */

1638

lower_privileges();

1639

return EX_OSERR;

2369

1640

}

2370

} else if(debug){

2371

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

2372

interface);

2373

1641

}

2374

2375

1642

/* Sleep checking until interface is running.

2376

1643

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

2377

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

2378

if(interface_is_running(interface)){

1644

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

1645

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

1646

if(ret == -1){

1647

perror_plus("ioctl SIOCGIFFLAGS");

1648

} else if(network.ifr_flags & IFF_RUNNING){

2379

1649

break;

2380

1650

}

2381

1651

struct timespec sleeptime = { .tv_nsec = 250000000 };

2384

1654

perror_plus("nanosleep");

2385

1655

}

2386

1656

}

2387

2388

errno = old_errno;

2389

return 0;

2390

}

2391

2392

__attribute__((nonnull, warn_unused_result))

2393

int take_down_interface(const char *const interface){

2394

int old_errno = errno;

2395

struct ifreq network;

2396

unsigned int if_index = if_nametoindex(interface);

2397

if(if_index == 0){

2398

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

2399

errno = old_errno;

2400

return ENXIO;

1657

/* Close the socket */

1658

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

1659

if(ret == -1){

1660

perror_plus("close");

2401

1661

}

2402

if(interface_is_up(interface)){

2403

int ret_errno = 0;

2404

int ioctl_errno = 0;

2405

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

2406

ret_errno = errno;

2407

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

2408

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

2409

errno = old_errno;

2410

return ret_errno;

2411

}

2412

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

2413

2414

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

2415

if(sd == -1){

2416

ret_errno = errno;

2417

perror_plus("socket");

2418

errno = old_errno;

2419

return ret_errno;

2420

}

2421

2422

if(debug){

2423

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

2424

interface);

2425

}

2426

2427

/* Raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

}

2433

2434

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

2435

ioctl_errno = errno;

2436

2437

/* If raise_privileges() succeeded above */

2438

if(ret_errno == 0){

2439

/* Lower privileges */

2440

ret_errno = lower_privileges();

2441

if(ret_errno != 0){

2442

errno = ret_errno;

2443

perror_plus("Failed to lower privileges");

2444

}

2445

}

2446

2447

/* Close the socket */

2448

int ret = close(sd);

1662

#ifdef __linux__

1663

if(restore_loglevel){

1664

/* Restores kernel loglevel to default */

1665

ret = klogctl(7, NULL, 0);

2449

1666

if(ret == -1){

2450

perror_plus("close");

2451

}

2452

2453

if(ret_setflags == -1){

2454

errno = ioctl_errno;

2455

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2456

errno = old_errno;

2457

return ioctl_errno;

2458

}

2459

} else if(debug){

2460

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

2461

interface);

1667

perror_plus("klogctl");

1668

}

2462

1669

}

2463

2464

errno = old_errno;

2465

return 0;

1670

#endif /* __linux__ */

1671

/* Lower privileges */

1672

lower_privileges();

1673

return errno;

2466

1674

}

2467

1675

2468

1676

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

2469

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

2470

#if GNUTLS_VERSION_NUMBER >= 0x030606

2471

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

2472

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

2473

":%PROFILE_ULTRA",

2474

#elif GNUTLS_VERSION_NUMBER < 0x030600

2475

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

2476

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

2477

#else

2478

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

2479

#endif

2480

.current_server = NULL, .interfaces = NULL,

2481

.interfaces_size = 0 };

2482

1677

AvahiSServiceBrowser *sb = NULL;

2483

error_t ret_errno;

1678

int error;

2484

1679

int ret;

2485

1680

intmax_t tmpmax;

2486

1681

char *tmp;

2487

1682

int exitcode = EXIT_SUCCESS;

2488

char *interfaces_to_take_down = NULL;

2489

size_t interfaces_to_take_down_size = 0;

2490

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

2491

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

2492

char *tempdir = NULL;

1683

const char *interface = "";

1684

struct ifreq network;

1685

int sd = -1;

1686

bool take_down_interface = false;

1687

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

1688

bool tempdir_created = false;

2493

1689

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2494

1690

const char *seckey = PATHDIR "/" SECKEY;

2495

1691

const char *pubkey = PATHDIR "/" PUBKEY;

2496

#if GNUTLS_VERSION_NUMBER >= 0x030606

2497

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2498

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2499

#endif

2500

const char *dh_params_file = NULL;

2501

char *interfaces_hooks = NULL;

2502

1692

2503

1693

bool gnutls_initialized = false;

2504

1694

bool gpgme_initialized = false;

2550

1740

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

2551

1741

.arg = "FILE",

2552

1742

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

2553

.group = 1 },

2554

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

2555

.arg = "FILE",

2556

#if GNUTLS_VERSION_NUMBER >= 0x030606

2557

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

2558

#else

2559

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

2560

#endif

2561

.group = 1 },

2562

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

2563

.arg = "FILE",

2564

#if GNUTLS_VERSION_NUMBER >= 0x030606

2565

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

2566

#else

2567

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

2568

#endif

2569

.group = 1 },

1743

.group = 2 },

2570

1744

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

2571

1745

.arg = "BITS",

2572

1746

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

2573

1747

" Diffie-Hellman key exchange",

2574

1748

.group = 2 },

2575

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

2576

.arg = "FILE",

2577

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

2578

" for the Diffie-Hellman key exchange",

2579

.group = 2 },

2580

1749

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

2581

1750

.arg = "STRING",

2582

1751

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

2616

1785

connect_to = arg;

2617

1786

break;

2618

1787

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

2619

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

2620

arg, (int)',');

2621

if(ret_errno != 0){

2622

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

2623

}

1788

interface = arg;

2624

1789

break;

2625

1790

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

2626

1791

seckey = arg;

2628

1793

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

2629

1794

pubkey = arg;

2630

1795

break;

2631

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

2632

#if GNUTLS_VERSION_NUMBER >= 0x030606

2633

tls_privkey = arg;

2634

#endif

2635

break;

2636

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

2637

#if GNUTLS_VERSION_NUMBER >= 0x030606

2638

tls_pubkey = arg;

2639

#endif

2640

break;

2641

1796

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

2642

1797

errno = 0;

2643

1798

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

2647

1802

}

2648

1803

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

2649

1804

break;

2650

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

2651

dh_params_file = arg;

2652

break;

2653

1805

case 130: /* --priority */

2654

1806

mc.priority = arg;

2655

1807

break;

2678

1830

argp_state_help(state, state->out_stream,

2679

1831

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2680

1832

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

2682

1833

case -3: /* --usage */

2683

1834

argp_state_help(state, state->out_stream,

2684

1835

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

2686

1836

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

2687

1837

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

2688

1838

exit(argp_err_exit_status);

2697

1847

.args_doc = "",

2698

1848

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

2699

1849

" passwords from a Mandos server" };

2700

ret_errno = argp_parse(&argp, argc, argv,

2701

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2702

switch(ret_errno){

1850

ret = argp_parse(&argp, argc, argv,

1851

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1852

switch(ret){

2703

1853

case 0:

2704

1854

break;

2705

1855

case ENOMEM:

2706

1856

default:

2707

errno = ret_errno;

1857

errno = ret;

2708

1858

perror_plus("argp_parse");

2709

1859

exitcode = EX_OSERR;

2710

1860

goto end;

2713

1863

goto end;

2714

1864

}

2715

1865

}

2716

1866

2717

1867

{

2718

1868

/* Work around Debian bug #633582:

2719

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

1869

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

2720

1870

2721

/* Re-raise privileges */

2722

ret = raise_privileges();

2723

if(ret != 0){

2724

errno = ret;

2725

perror_plus("Failed to raise privileges");

2726

} else {

1871

/* Re-raise priviliges */

1872

if(raise_privileges() == 0){

2727

1873

struct stat st;

2728

1874

2729

1875

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

2743

1889

}

2744

1890

}

2745

1891

}

2746

close(seckey_fd);

1892

TEMP_FAILURE_RETRY(close(seckey_fd));

2747

1893

}

2748

1894

}

2749

1895

2750

1896

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

2751

1897

int pubkey_fd = open(pubkey, O_RDONLY);

2752

1898

if(pubkey_fd == -1){

2764

1910

}

2765

1911

}

2766

1912

}

2767

close(pubkey_fd);

2768

}

2769

}

2770

2771

if(dh_params_file != NULL

2772

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

2773

int dhparams_fd = open(dh_params_file, O_RDONLY);

2774

if(dhparams_fd == -1){

2775

perror_plus("open");

2776

} else {

2777

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

2778

if(ret == -1){

2779

perror_plus("fstat");

2780

} else {

2781

if(S_ISREG(st.st_mode)

2782

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

2783

ret = fchown(dhparams_fd, uid, gid);

2784

if(ret == -1){

2785

perror_plus("fchown");

2786

}

2787

}

2788

}

2789

close(dhparams_fd);

2790

}

2791

}

2792

1913

TEMP_FAILURE_RETRY(close(pubkey_fd));

1914

}

1915

}

1916

2793

1917

/* Lower privileges */

2794

ret = lower_privileges();

2795

if(ret != 0){

2796

errno = ret;

2797

perror_plus("Failed to lower privileges");

2798

}

2799

}

2800

}

2801

2802

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

2803

{

2804

char *interface = NULL;

2805

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

2806

interface))){

2807

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

2808

and if_nametoindex(interface) == 0){

2809

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

2810

fprintf_plus(stderr, "Not using nonexisting interface"

2811

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

2812

}

2813

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

2814

interface = NULL;

1918

errno = 0;

1919

ret = seteuid(uid);

1920

if(ret == -1){

1921

perror_plus("seteuid");

2815

1922

}

2816

1923

}

2817

1924

}

2818

1925

2819

1926

/* Run network hooks */

2820

{

2821

if(mc.interfaces != NULL){

2822

interfaces_hooks = malloc(mc.interfaces_size);

2823

if(interfaces_hooks == NULL){

1927

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

1928

goto end;

1929

}

1930

1931

if(not debug){

1932

avahi_set_log_function(empty_log);

1933

}

1934

1935

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

1936

struct dirent **direntries;

1937

/* First look for interfaces that are up */

1938

ret = scandir(sys_class_net, &direntries, up_interface,

1939

alphasort);

1940

if(ret == 0){

1941

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

1942

free(direntries);

1943

ret = scandir(sys_class_net, &direntries, good_interface,

1944

alphasort);

1945

}

1946

if(ret >= 1){

1947

/* Pick the first interface returned */

1948

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

1949

if(debug){

1950

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

1951

}

1952

if(interface == NULL){

2824

1953

perror_plus("malloc");

1954

free(direntries);

1955

exitcode = EXIT_FAILURE;

2825

1956

goto end;

2826

1957

}

2827

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

2828

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

1958

free(direntries);

1959

} else {

1960

free(direntries);

1961

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

1962

exitcode = EXIT_FAILURE;

1963

goto end;

2829

1964

}

2830

run_network_hooks("start", interfaces_hooks != NULL ?

2831

interfaces_hooks : "", delay);

2832

}

2833

2834

if(not debug){

2835

avahi_set_log_function(empty_log);

2836

1965

}

2837

1966

2838

1967

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

2839

1968

from the signal handler */

2840

1969

/* Initialize the pseudo-RNG for Avahi */

2841

1970

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

2842

simple_poll = avahi_simple_poll_new();

2843

if(simple_poll == NULL){

1971

mc.simple_poll = avahi_simple_poll_new();

1972

if(mc.simple_poll == NULL){

2844

1973

fprintf_plus(stderr,

2845

1974

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

2846

1975

exitcode = EX_UNAVAILABLE;

2910

2039

}

2911

2040

}

2912

2041

2913

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

2914

if(mc.interfaces == NULL){

2915

struct dirent **direntries = NULL;

2916

/* Look for any good interfaces */

2917

ret = scandir(sys_class_net, &direntries, good_interface,

2918

alphasort);

2919

if(ret >= 1){

2920

/* Add all found interfaces to interfaces list */

2921

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

2922

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

2923

direntries[i]->d_name);

2924

if(ret_errno != 0){

2925

errno = ret_errno;

2926

perror_plus("argz_add");

2927

free(direntries[i]);

2928

continue;

2929

}

2930

if(debug){

2931

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

2932

direntries[i]->d_name);

2933

}

2934

free(direntries[i]);

2935

}

2936

free(direntries);

2937

} else {

2938

if(ret == 0){

2939

free(direntries);

2940

}

2941

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

2942

exitcode = EXIT_FAILURE;

2943

goto end;

2944

}

2945

}

2946

2947

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

2948

{

2949

char *interface = NULL;

2950

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

2951

interface))){

2952

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

2953

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

2954

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

2955

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

2956

interface);

2957

interface = NULL;

2958

while((interface = argz_next(mc.interfaces,

2959

mc.interfaces_size, interface))){

2960

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

2961

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

2962

interface);

2963

interface = NULL;

2964

}

2965

}

2966

break;

2967

}

2968

bool interface_was_up = interface_is_up(interface);

2969

errno = bring_up_interface(interface, delay);

2970

if(not interface_was_up){

2971

if(errno != 0){

2972

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

2973

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

2974

} else {

2975

errno = argz_add(&interfaces_to_take_down,

2976

&interfaces_to_take_down_size,

2977

interface);

2978

if(errno != 0){

2979

perror_plus("argz_add");

2980

}

2981

}

2982

}

2983

}

2984

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

2985

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

2986

}

2987

}

2988

2989

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

2990

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

2991

if(debug){

2992

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

2993

mc.interfaces);

2994

}

2995

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

2042

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

2043

if((interface[0] != '\0') and (strcmp(interface, "none") != 0)){

2044

ret = bring_up_interface(interface, delay);

2045

if(ret){

2046

errno = ret;

2047

perror_plus("Failed to bring up interface");

2048

}

2996

2049

}

2997

2050

2998

2051

if(quit_now){

2999

2052

goto end;

3000

2053

}

3001

2054

3002

#if GNUTLS_VERSION_NUMBER >= 0x030606

3003

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

3004

#elif GNUTLS_VERSION_NUMBER < 0x030600

3005

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

3006

#else

3007

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

3008

#endif

2055

ret = init_gnutls_global(pubkey, seckey);

3009

2056

if(ret == -1){

3010

2057

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

3011

2058

exitcode = EX_UNAVAILABLE;

3018

2065

goto end;

3019

2066

}

3020

2067

3021

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

3022

tempdir = mkdtemp(run_tempdir);

3023

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

3024

if(debug){

3025

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

3026

run_tempdir, old_tempdir);

3027

}

3028

tempdir = mkdtemp(old_tempdir);

3029

}

3030

if(tempdir == NULL){

2068

if(mkdtemp(tempdir) == NULL){

3031

2069

perror_plus("mkdtemp");

3032

2070

goto end;

3033

2071

}

2072

tempdir_created = true;

3034

2073

3035

2074

if(quit_now){

3036

2075

goto end;

3037

2076

}

3038

2077

3039

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

2078

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

3040

2079

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

3041

2080

exitcode = EX_UNAVAILABLE;

3042

2081

goto end;

3063

2102

goto end;

3064

2103

}

3065

2104

3066

in_port_t port;

2105

uint16_t port;

3067

2106

errno = 0;

3068

2107

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

3069

2108

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

3070

or tmpmax != (in_port_t)tmpmax){

2109

or tmpmax != (uint16_t)tmpmax){

3071

2110

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

3072

2111

exitcode = EX_USAGE;

3073

2112

goto end;

3074

2113

}

3075

2114

3076

2115

if(quit_now){

3077

2116

goto end;

3078

2117

}

3079

2118

3080

port = (in_port_t)tmpmax;

2119

port = (uint16_t)tmpmax;

3081

2120

*address = '\0';

3082

2121

/* Colon in address indicates IPv6 */

3083

2122

int af;

3099

2138

}

3100

2139

3101

2140

while(not quit_now){

3102

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

3103

&mc);

2141

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

3104

2142

if(quit_now or ret == 0){

3105

2143

break;

3106

2144

}

3108

2146

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

3109

2147

(int)retry_interval);

3110

2148

}

3111

sleep((unsigned int)retry_interval);

2149

sleep((int)retry_interval);

3112

2150

}

3113

2151

3114

if(not quit_now){

2152

if (not quit_now){

3115

2153

exitcode = EXIT_SUCCESS;

3116

2154

}

3117

2155

3132

2170

config.publish_domain = 0;

3133

2171

3134

2172

/* Allocate a new server */

3135

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3136

&config, NULL, NULL, &ret);

2173

mc.server = avahi_server_new(avahi_simple_poll_get

2174

(mc.simple_poll), &config, NULL,

2175

NULL, &error);

3137

2176

3138

2177

/* Free the Avahi configuration data */

3139

2178

avahi_server_config_free(&config);

3142

2181

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

3143

2182

if(mc.server == NULL){

3144

2183

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

3145

avahi_strerror(ret));

2184

avahi_strerror(error));

3146

2185

exitcode = EX_UNAVAILABLE;

3147

2186

goto end;

3148

2187

}

3154

2193

/* Create the Avahi service browser */

3155

2194

sb = avahi_s_service_browser_new(mc.server, if_index,

3156

2195

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3157

NULL, 0, browse_callback,

3158

(void *)&mc);

2196

NULL, 0, browse_callback, NULL);

3159

2197

if(sb == NULL){

3160

2198

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

3161

2199

avahi_strerror(avahi_server_errno(mc.server)));

3172

2210

if(debug){

3173

2211

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

3174

2212

}

3175

3176

ret = avahi_loop_with_timeout(simple_poll,

3177

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

2213

2214

ret = avahi_loop_with_timeout(mc.simple_poll,

2215

(int)(retry_interval * 1000));

3178

2216

if(debug){

3179

2217

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

3180

2218

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

3183

2221

end:

3184

2222

3185

2223

if(debug){

3186

if(signal_received){

3187

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

3188

argv[0], signal_received,

3189

strsignal(signal_received));

3190

} else {

3191

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

3192

}

2224

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

3193

2225

}

3194

2226

3195

2227

/* Cleanup things */

3196

free(mc.interfaces);

3197

3198

2228

if(sb != NULL)

3199

2229

avahi_s_service_browser_free(sb);

3200

2230

3201

2231

if(mc.server != NULL)

3202

2232

avahi_server_free(mc.server);

3203

2233

3204

if(simple_poll != NULL)

3205

avahi_simple_poll_free(simple_poll);

2234

if(mc.simple_poll != NULL)

2235

avahi_simple_poll_free(mc.simple_poll);

3206

2236

3207

2237

if(gnutls_initialized){

3208

2238

gnutls_certificate_free_credentials(mc.cred);

2239

gnutls_global_deinit();

3209

2240

gnutls_dh_params_deinit(mc.dh_params);

3210

2241

}

3211

2242

3219

2250

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

3220

2251

while(mc.current_server != NULL){

3221

2252

server *next = mc.current_server->next;

3222

#ifdef __GNUC__

3223

#pragma GCC diagnostic push

3224

#pragma GCC diagnostic ignored "-Wcast-qual"

3225

#endif

3226

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

3227

#ifdef __GNUC__

3228

#pragma GCC diagnostic pop

3229

#endif

3230

2253

free(mc.current_server);

3231

2254

mc.current_server = next;

3232

2255

}

3233

2256

}

3234

2257

3235

/* Re-raise privileges */

2258

/* Run network hooks */

2259

run_network_hooks("stop", interface, delay);

2260

2261

/* Re-raise priviliges */

3236

2262

{

3237

ret = raise_privileges();

3238

if(ret != 0){

3239

errno = ret;

3240

perror_plus("Failed to raise privileges");

3241

} else {

3242

3243

/* Run network hooks */

3244

run_network_hooks("stop", interfaces_hooks != NULL ?

3245

interfaces_hooks : "", delay);

3246

3247

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

3248

{

3249

char *interface = NULL;

3250

while((interface = argz_next(interfaces_to_take_down,

3251

interfaces_to_take_down_size,

3252

interface))){

3253

ret = take_down_interface(interface);

3254

if(ret != 0){

3255

errno = ret;

3256

perror_plus("Failed to take down interface");

3257

}

3258

}

3259

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

3260

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

3261

" down\n");

3262

}

3263

}

3264

}

2263

raise_privileges();

3265

2264

3266

ret = lower_privileges_permanently();

3267

if(ret != 0){

3268

errno = ret;

3269

perror_plus("Failed to lower privileges permanently");

2265

/* Take down the network interface */

2266

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

2267

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

2268

if(ret == -1){

2269

perror_plus("ioctl SIOCGIFFLAGS");

2270

} else if(network.ifr_flags & IFF_UP){

2271

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

2272

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

2273

if(ret == -1){

2274

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2275

}

2276

}

2277

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

2278

if(ret == -1){

2279

perror_plus("close");

2280

}

3270

2281

}

3271

2282

}

3272

3273

free(interfaces_to_take_down);

3274

free(interfaces_hooks);

3275

3276

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

3277

uintmax_t level){

2283

/* Lower privileges permanently */

2284

errno = 0;

2285

ret = setuid(uid);

2286

if(ret == -1){

2287

perror_plus("setuid");

2288

}

2289

2290

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

2291

if(tempdir_created){

3278

2292

struct dirent **direntries = NULL;

3279

int dret;

3280

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

3281

O_RDONLY

3282

| O_NOFOLLOW

3283

| O_DIRECTORY

3284

| O_PATH));

3285

if(dir_fd == -1){

3286

perror_plus("open");

3287

return;

3288

}

3289

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

3290

notdotentries, alphasort);

3291

if(numentries >= 0){

2293

struct dirent *direntry = NULL;

2294

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

2295

alphasort);

2296

if (numentries > 0){

3292

2297

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

3293

if(debug){

3294

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

3295

dirname, direntries[i]->d_name);

3296

}

3297

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

3298

if(dret == -1){

3299

if(errno == EISDIR){

3300

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

3301

AT_REMOVEDIR);

3302

}

3303

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

3304

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

3305

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

3306

/* Recurse only in this special case */

3307

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

3308

dret = 0;

3309

}

3310

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

3311

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

3312

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

3313

}

3314

}

3315

free(direntries[i]);

3316

}

3317

3318

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

3319

free(direntries);

3320

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3321

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

3322

perror_plus("rmdir");

3323

}

3324

} else {

3325

perror_plus("scandirat");

3326

}

3327

close(dir_fd);

3328

}

3329

3330

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

3331

if(tempdir != NULL){

3332

clean_dir_at(-1, tempdir, 0);

2298

direntry = direntries[i];

2299

char *fullname = NULL;

2300

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

2301

direntry->d_name);

2302

if(ret < 0){

2303

perror_plus("asprintf");

2304

continue;

2305

}

2306

ret = remove(fullname);

2307

if(ret == -1){

2308

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

2309

strerror(errno));

2310

}

2311

free(fullname);

2312

}

2313

}

2314

2315

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

2316

free(direntries);

2317

if (numentries == -1){

2318

perror_plus("scandir");

2319

}

2320

ret = rmdir(tempdir);

2321

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

2322

perror_plus("rmdir");

2323

}

3333

2324

}

3334

2325

3335

2326

if(quit_now){