/mandos/trunk : revision 556

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

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*

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* Everything else is

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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*

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

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

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

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

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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

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

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program_invocation_short_name */

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

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

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*/

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

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

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

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unlinkat() */

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

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

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

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

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

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argp_state, struct argp,

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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gnutls_*

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init_gnutls_session(),

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GNUTLS_* */

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#if GNUTLS_VERSION_NUMBER < 0x030600

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#include <gnutls/openpgp.h>

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/* gnutls_certificate_set_openpgp_key_file(),

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GNUTLS_OPENPGP_FMT_BASE64 */

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#elif GNUTLS_VERSION_NUMBER >= 0x030606

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

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GNUTLS_PKCS_PLAIN,

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GNUTLS_PKCS_NULL_PASSWORD */

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#endif

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/* GPGME */

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

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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#define TLS_PRIVKEY "tls-privkey.pem"

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#define TLS_PUBKEY "tls-pubkey.pem"

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

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bool debug = false;

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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perror(print_text);

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}

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

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

220

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

232

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return buffer_capacity;

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}

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

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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

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int af){

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int ret;

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

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if(new_server == NULL){

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.af = af };

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if(new_server->ip == NULL){

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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__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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if(*current_server == NULL){

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if (mc.current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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

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} else {

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

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new_server->next = *current_server;

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

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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mc.current_server->prev = new_server;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return false;

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}

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return true;

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}

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

284

__attribute__((warn_unused_result))

285

int raise_privileges(void){

286

int old_errno = errno;

287

int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

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int old_errno = errno;

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int ret = raise_privileges();

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if(ret != 0){

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errno = old_errno;

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return ret;

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}

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;

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}

319

errno = old_errno;

320

return ret;

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}

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/* Lower privileges permanently */

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__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

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int old_errno = errno;

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int ret = 0;

328

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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/*

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* Initialize GPGME.

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*/

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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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

248

const char *tempdir){

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gpgme_error_t rc;

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gpgme_engine_info_t engine_info;

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346

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/*

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

348

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*/

349

bool import_key(const char * const filename){

256

bool import_key(const char *filename){

350

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int ret;

351

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int fd;

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gpgme_data_t pgp_data;

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return false;

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}

359

266

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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;

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}

371

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

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break;

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}

374

if(debug){

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

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}

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;

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}

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

267

rc = gpgme_data_new_from_fd(&pgp_data, fd);

410

268

if(rc != GPG_ERR_NO_ERROR){

411

269

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

413

271

return false;

414

272

}

415

273

416

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

274

rc = gpgme_op_import(mc.ctx, pgp_data);

417

275

if(rc != GPG_ERR_NO_ERROR){

418

276

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

419

277

gpgme_strsource(rc), gpgme_strerror(rc));

420

278

return false;

421

279

}

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

280

498

ret = close(fd);

281

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

499

282

if(ret == -1){

500

283

perror_plus("close");

501

284

}

538

321

}

539

322

540

323

/* Create new GPGME "context" */

541

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

324

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

542

325

if(rc != GPG_ERR_NO_ERROR){

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

326

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

327

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

328

gpgme_strerror(rc));

545

329

return false;

546

330

}

547

331

556

340

* Decrypt OpenPGP data.

557

341

* Returns -1 on error

558

342

*/

559

__attribute__((nonnull, warn_unused_result))

560

343

static ssize_t pgp_packet_decrypt(const char *cryptotext,

561

344

size_t crypto_size,

562

char **plaintext,

563

mandos_context *mc){

345

char **plaintext){

564

346

gpgme_data_t dh_crypto, dh_plain;

565

347

gpgme_error_t rc;

566

348

ssize_t ret;

583

365

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

584

366

rc = gpgme_data_new(&dh_plain);

585

367

if(rc != GPG_ERR_NO_ERROR){

586

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

368

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

369

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

587

370

gpgme_strsource(rc), gpgme_strerror(rc));

588

371

gpgme_data_release(dh_crypto);

589

372

return -1;

591

374

592

375

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

593

376

data buffer */

594

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

377

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

595

378

if(rc != GPG_ERR_NO_ERROR){

596

379

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

597

380

gpgme_strsource(rc), gpgme_strerror(rc));

598

381

plaintext_length = -1;

599

382

if(debug){

600

383

gpgme_decrypt_result_t result;

601

result = gpgme_op_decrypt_result(mc->ctx);

384

result = gpgme_op_decrypt_result(mc.ctx);

602

385

if(result == NULL){

603

386

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

604

387

} 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");

388

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

389

result->unsupported_algorithm);

390

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

391

result->wrong_key_usage);

611

392

if(result->file_name != NULL){

612

393

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

613

394

}

614

615

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

616

r = r->next){

395

gpgme_recipient_t recipient;

396

recipient = result->recipients;

397

while(recipient != NULL){

617

398

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);

399

gpgme_pubkey_algo_name

400

(recipient->pubkey_algo));

401

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

620

402

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

621

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

403

recipient->status == GPG_ERR_NO_SECKEY

404

? "No" : "Yes");

405

recipient = recipient->next;

622

406

}

623

407

}

624

408

}

680

464

return plaintext_length;

681

465

}

682

466

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);

467

static const char * safer_gnutls_strerror(int value){

468

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

469

-Wunreachable-code */

470

if(ret == NULL)

471

ret = "(unknown)";

472

return ret;

694

473

}

695

474

696

475

/* GnuTLS log function callback */

697

__attribute__((nonnull))

698

476

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

699

477

const char* string){

700

478

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

701

479

}

702

480

703

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

704

481

static int init_gnutls_global(const char *pubkeyfilename,

705

const char *seckeyfilename,

706

const char *dhparamsfilename,

707

mandos_context *mc){

482

const char *seckeyfilename){

708

483

int ret;

709

484

710

485

if(debug){

711

486

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

712

487

}

713

488

489

ret = gnutls_global_init();

490

if(ret != GNUTLS_E_SUCCESS){

491

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

492

safer_gnutls_strerror(ret));

493

return -1;

494

}

495

714

496

if(debug){

715

497

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

716

498

* - GnuTLS manual

720

502

}

721

503

722

504

/* OpenPGP credentials */

723

ret = gnutls_certificate_allocate_credentials(&mc->cred);

505

ret = gnutls_certificate_allocate_credentials(&mc.cred);

724

506

if(ret != GNUTLS_E_SUCCESS){

725

507

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

726

508

safer_gnutls_strerror(ret));

509

gnutls_global_deinit();

727

510

return -1;

728

511

}

729

512

730

513

if(debug){

731

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

732

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

514

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

515

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

733

516

pubkeyfilename,

734

517

seckeyfilename);

735

518

}

736

519

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

520

ret = gnutls_certificate_set_openpgp_key_file

751

(mc->cred, pubkeyfilename, seckeyfilename,

521

(mc.cred, pubkeyfilename, seckeyfilename,

752

522

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

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

755

#endif

756

523

if(ret != GNUTLS_E_SUCCESS){

757

524

fprintf_plus(stderr,

758

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

525

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

759

526

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

760

527

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

761

528

safer_gnutls_strerror(ret));

763

530

}

764

531

765

532

/* GnuTLS server initialization */

766

ret = gnutls_dh_params_init(&mc->dh_params);

533

ret = gnutls_dh_params_init(&mc.dh_params);

767

534

if(ret != GNUTLS_E_SUCCESS){

768

535

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

769

536

" initialization: %s\n",

770

537

safer_gnutls_strerror(ret));

771

538

goto globalfail;

772

539

}

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

}

540

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

541

if(ret != GNUTLS_E_SUCCESS){

542

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

543

safer_gnutls_strerror(ret));

544

goto globalfail;

545

}

546

547

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

955

548

956

549

return 0;

957

550

958

551

globalfail:

959

552

960

gnutls_certificate_free_credentials(mc->cred);

961

gnutls_dh_params_deinit(mc->dh_params);

553

gnutls_certificate_free_credentials(mc.cred);

554

gnutls_global_deinit();

555

gnutls_dh_params_deinit(mc.dh_params);

962

556

return -1;

963

557

}

964

558

965

__attribute__((nonnull, warn_unused_result))

966

static int init_gnutls_session(gnutls_session_t *session,

967

mandos_context *mc){

559

static int init_gnutls_session(gnutls_session_t *session){

968

560

int ret;

969

561

/* GnuTLS session creation */

970

562

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

));

563

ret = gnutls_init(session, GNUTLS_SERVER);

979

564

if(quit_now){

980

565

return -1;

981

566

}

989

574

{

990

575

const char *err;

991

576

do {

992

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

577

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

993

578

if(quit_now){

994

579

gnutls_deinit(*session);

995

580

return -1;

1006

591

1007

592

do {

1008

593

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1009

mc->cred);

594

mc.cred);

1010

595

if(quit_now){

1011

596

gnutls_deinit(*session);

1012

597

return -1;

1022

607

/* ignore client certificate if any. */

1023

608

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1024

609

610

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

611

1025

612

return 0;

1026

613

}

1027

614

1029

616

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

1030

617

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

1031

618

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

619

/* 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,

620

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

1208

621

AvahiIfIndex if_index,

1209

int af, mandos_context *mc){

622

int af){

1210

623

int ret, tcp_sd = -1;

1211

624

ssize_t sret;

1212

struct sockaddr_storage to;

625

union {

626

struct sockaddr_in in;

627

struct sockaddr_in6 in6;

628

} to;

1213

629

char *buffer = NULL;

1214

630

char *decrypted_buffer = NULL;

1215

631

size_t buffer_length = 0;

1218

634

int retval = -1;

1219

635

gnutls_session_t session;

1220

636

int pf; /* Protocol family */

1221

bool route_added = false;

1222

637

1223

638

errno = 0;

1224

639

1240

655

return -1;

1241

656

}

1242

657

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);

658

ret = init_gnutls_session(&session);

1277

659

if(ret != 0){

1278

660

return -1;

1279

661

}

1280

662

1281

663

if(debug){

1282

664

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

1283

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

665

PRIu16 "\n", ip, port);

1284

666

}

1285

667

1286

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

668

tcp_sd = socket(pf, SOCK_STREAM, 0);

1287

669

if(tcp_sd < 0){

1288

670

int e = errno;

1289

671

perror_plus("socket");

1296

678

goto mandos_end;

1297

679

}

1298

680

681

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

1299

682

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);

683

to.in6.sin6_family = (sa_family_t)af;

684

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

1303

685

} 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);

686

to.in.sin_family = (sa_family_t)af;

687

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

1307

688

}

1308

689

if(ret < 0 ){

1309

690

int e = errno;

1318

699

goto mandos_end;

1319

700

}

1320

701

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)){

702

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

703

-Wconversion and

704

-Wunreachable-code */

705

706

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

707

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

708

-Wunreachable-code*/

1324

709

if(if_index == AVAHI_IF_UNSPEC){

1325

710

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

1326

711

" incomplete without a network interface\n");

1328

713

goto mandos_end;

1329

714

}

1330

715

/* Set the network interface number as scope */

1331

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

716

to.in6.sin6_scope_id = (uint32_t)if_index;

1332

717

}

1333

718

} else {

1334

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

719

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

720

-Wconversion and

721

-Wunreachable-code */

1335

722

}

1336

723

1337

724

if(quit_now){

1345

732

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

1346

733

perror_plus("if_indextoname");

1347

734

} else {

1348

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

1349

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

735

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

736

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

1350

737

}

1351

738

} else {

1352

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

1353

ip, (uintmax_t)port);

739

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

740

ip, port);

1354

741

}

1355

742

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1356

743

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;

744

const char *pcret;

745

if(af == AF_INET6){

746

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

747

sizeof(addrstr));

748

} else {

749

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

750

sizeof(addrstr));

751

}

752

if(pcret == NULL){

753

perror_plus("inet_ntop");

754

} else {

755

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

756

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

757

}

758

}

759

}

760

761

if(quit_now){

762

errno = EINTR;

763

goto mandos_end;

764

}

765

766

if(af == AF_INET6){

767

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

768

} else {

769

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

770

}

771

if(ret < 0){

772

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

773

int e = errno;

774

perror_plus("connect");

775

errno = e;

776

}

777

goto mandos_end;

778

}

779

780

if(quit_now){

781

errno = EINTR;

782

goto mandos_end;

1437

783

}

1438

784

1439

785

const char *out = mandos_protocol_version;

1475

821

goto mandos_end;

1476

822

}

1477

823

1478

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

1479

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

1480

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

1481

gnutls_transport_set_ptr(session,

1482

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

824

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

825

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1483

826

1484

827

if(quit_now){

1485

828

errno = EINTR;

1590

933

if(buffer_length > 0){

1591

934

ssize_t decrypted_buffer_size;

1592

935

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1593

&decrypted_buffer, mc);

936

&decrypted_buffer);

1594

937

if(decrypted_buffer_size >= 0){

1595

938

1596

clearerr(stdout);

1597

939

written = 0;

1598

940

while(written < (size_t) decrypted_buffer_size){

1599

941

if(quit_now){

1615

957

}

1616

958

written += (size_t)ret;

1617

959

}

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

960

retval = 0;

1629

961

}

1630

962

}

1633

965

1634

966

mandos_end:

1635

967

{

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

968

int e = errno;

1643

969

free(decrypted_buffer);

1644

970

free(buffer);

1645

971

if(tcp_sd >= 0){

1646

ret = close(tcp_sd);

972

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

1647

973

}

1648

974

if(ret == -1){

1649

975

if(e == 0){

1674

1000

AVAHI_GCC_UNUSED AvahiStringList *txt,

1675

1001

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1676

1002

flags,

1677

void *mc){

1678

if(r == NULL){

1679

return;

1680

}

1003

AVAHI_GCC_UNUSED void* userdata){

1004

assert(r);

1681

1005

1682

1006

/* Called whenever a service has been resolved successfully or

1683

1007

timed out */

1684

1008

1685

1009

if(quit_now){

1686

avahi_s_service_resolver_free(r);

1687

1010

return;

1688

1011

}

1689

1012

1693

1016

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

1694

1017

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

1695

1018

domain,

1696

avahi_strerror(avahi_server_errno

1697

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

1019

avahi_strerror(avahi_server_errno(mc.server)));

1698

1020

break;

1699

1021

1700

1022

case AVAHI_RESOLVER_FOUND:

1706

1028

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

1707

1029

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

1708

1030

}

1709

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

1710

interface,

1711

avahi_proto_to_af(proto),

1712

mc);

1031

int ret = start_mandos_communication(ip, port, interface,

1032

avahi_proto_to_af(proto));

1713

1033

if(ret == 0){

1714

avahi_simple_poll_quit(simple_poll);

1034

avahi_simple_poll_quit(mc.simple_poll);

1715

1035

} else {

1716

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

1717

avahi_proto_to_af(proto),

1718

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

1036

if(not add_server(ip, port, interface,

1037

avahi_proto_to_af(proto))){

1719

1038

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

1720

1039

" list\n", name);

1721

1040

}

1734

1053

const char *domain,

1735

1054

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1736

1055

flags,

1737

void *mc){

1738

if(b == NULL){

1739

return;

1740

}

1056

AVAHI_GCC_UNUSED void* userdata){

1057

assert(b);

1741

1058

1742

1059

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

1743

1060

is removed from the LAN */

1751

1068

case AVAHI_BROWSER_FAILURE:

1752

1069

1753

1070

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);

1071

avahi_strerror(avahi_server_errno(mc.server)));

1072

avahi_simple_poll_quit(mc.simple_poll);

1757

1073

return;

1758

1074

1759

1075

case AVAHI_BROWSER_NEW:

1762

1078

the callback function is called the Avahi server will free the

1763

1079

resolver for us. */

1764

1080

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)

1081

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

1082

name, type, domain, protocol, 0,

1083

resolve_callback, NULL) == NULL)

1769

1084

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

1770

1085

" %s\n", name,

1771

avahi_strerror(avahi_server_errno

1772

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

1086

avahi_strerror(avahi_server_errno(mc.server)));

1773

1087

break;

1774

1088

1775

1089

case AVAHI_BROWSER_REMOVE:

1794

1108

signal_received = sig;

1795

1109

int old_errno = errno;

1796

1110

/* set main loop to exit */

1797

if(simple_poll != NULL){

1798

avahi_simple_poll_quit(simple_poll);

1111

if(mc.simple_poll != NULL){

1112

avahi_simple_poll_quit(mc.simple_poll);

1799

1113

}

1800

1114

errno = old_errno;

1801

1115

}

1802

1116

1803

__attribute__((nonnull, warn_unused_result))

1804

1117

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

1805

1118

int ret;

1806

int old_errno;

1807

1119

1808

1120

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

1809

1121

if(s < 0){

1810

old_errno = errno;

1811

1122

perror_plus("socket");

1812

errno = old_errno;

1813

1123

return false;

1814

1124

}

1815

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

1816

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

1125

strcpy(ifr->ifr_name, ifname);

1817

1126

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1818

1127

if(ret == -1){

1819

1128

if(debug){

1820

old_errno = errno;

1821

1129

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

1130

}

1829

1131

return false;

1830

1132

}

1831

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

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1836

1133

return true;

1837

1134

}

1838

1135

1839

__attribute__((nonnull, warn_unused_result))

1840

1136

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

1841

1137

1842

1138

/* Reject the loopback device */

1884

1180

* corresponds to an acceptable network device.

1885

1181

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

1886

1182

*/

1887

__attribute__((nonnull, warn_unused_result))

1888

1183

int good_interface(const struct dirent *if_entry){

1889

1184

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

1890

1185

return 0;

1906

1201

}

1907

1202

1908

1203

/*

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))

1204

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

1205

* corresponds to an acceptable network device which is up.

1206

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

1207

*/

1208

int up_interface(const struct dirent *if_entry){

1209

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

1210

return 0;

1211

}

1212

1213

struct ifreq ifr;

1214

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

1215

if(debug){

1216

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

1217

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

1218

}

1219

return 0;

1220

}

1221

1222

/* Reject down interfaces */

1223

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

1224

if(debug){

1225

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

1226

if_entry->d_name);

1227

}

1228

return 0;

1229

}

1230

1231

/* Reject non-running interfaces */

1232

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

1233

if(debug){

1234

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

1235

if_entry->d_name);

1236

}

1237

return 0;

1238

}

1239

1240

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

1241

return 0;

1242

}

1243

return 1;

1244

}

1245

1943

1246

int notdotentries(const struct dirent *direntry){

1944

1247

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

1945

1248

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

1952

1255

}

1953

1256

1954

1257

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

1955

__attribute__((nonnull, warn_unused_result))

1956

1258

int runnable_hook(const struct dirent *direntry){

1957

1259

int ret;

1958

1260

size_t sret;

1966

1268

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

1967

1269

"abcdefghijklmnopqrstuvwxyz"

1968

1270

"0123456789"

1969

"_.-");

1271

"_-");

1970

1272

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

1971

1273

/* Contains non-allowed characters */

1972

1274

if(debug){

1976

1278

return 0;

1977

1279

}

1978

1280

1979

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

1281

char *fullname = NULL;

1282

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

1283

if(ret < 0){

1284

perror_plus("asprintf");

1285

return 0;

1286

}

1287

1288

ret = stat(fullname, &st);

1980

1289

if(ret == -1){

1981

1290

if(debug){

1982

1291

perror_plus("Could not stat hook");

2006

1315

return 1;

2007

1316

}

2008

1317

2009

__attribute__((nonnull, warn_unused_result))

2010

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2011

mandos_context *mc){

1318

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2012

1319

int ret;

2013

1320

struct timespec now;

2014

1321

struct timespec waited_time;

2015

1322

intmax_t block_time;

2016

1323

2017

1324

while(true){

2018

if(mc->current_server == NULL){

2019

if(debug){

1325

if(mc.current_server == NULL){

1326

if (debug){

2020

1327

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

2021

1328

" No timeout!\n");

2022

1329

}

2023

1330

ret = avahi_simple_poll_iterate(s, -1);

2024

1331

} else {

2025

if(debug){

1332

if (debug){

2026

1333

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

2027

1334

" it, or wait\n");

2028

1335

}

2035

1342

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

2036

1343

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

2037

1344

waited_time.tv_sec = (now.tv_sec

2038

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

1345

- mc.current_server->last_seen.tv_sec);

2039

1346

waited_time.tv_nsec = (now.tv_nsec

2040

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

1347

- mc.current_server->last_seen.tv_nsec);

2041

1348

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

2042

1349

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

2043

1350

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

2045

1352

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

2046

1353

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

2047

1354

2048

if(debug){

1355

if (debug){

2049

1356

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

2050

1357

block_time);

2051

1358

}

2052

1359

2053

1360

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);

1361

ret = start_mandos_communication(mc.current_server->ip,

1362

mc.current_server->port,

1363

mc.current_server->if_index,

1364

mc.current_server->af);

2058

1365

if(ret == 0){

2059

avahi_simple_poll_quit(s);

1366

avahi_simple_poll_quit(mc.simple_poll);

2060

1367

return 0;

2061

1368

}

2062

1369

ret = clock_gettime(CLOCK_MONOTONIC,

2063

&mc->current_server->last_seen);

1370

&mc.current_server->last_seen);

2064

1371

if(ret == -1){

2065

1372

perror_plus("clock_gettime");

2066

1373

return -1;

2067

1374

}

2068

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

1375

mc.current_server = mc.current_server->next;

2069

1376

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

2070

1377

servers, but don't block */

2071

1378

}

2073

1380

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

2074

1381

}

2075

1382

if(ret != 0){

2076

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

1383

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

2077

1384

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

2078

1385

}

2079

1386

}

2080

1387

}

2081

1388

}

2082

1389

2083

__attribute__((nonnull))

2084

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

1390

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

2085

1391

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);

1392

struct dirent **direntries;

1393

struct dirent *direntry;

1394

int ret;

1395

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

1396

alphasort);

2109

1397

if(numhooks == -1){

2110

1398

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){

1399

} else {

1400

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

1401

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

1402

direntry = direntries[i];

1403

char *fullname = NULL;

1404

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

1405

if(ret < 0){

2168

1406

perror_plus("asprintf");

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

if(ret == -1){

1407

continue;

1408

}

1409

if(debug){

1410

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

1411

direntry->d_name);

1412

}

1413

pid_t hook_pid = fork();

1414

if(hook_pid == 0){

1415

/* Child */

1416

/* Raise privileges */

1417

errno = 0;

1418

ret = seteuid(0);

1419

if(ret == -1){

1420

perror_plus("seteuid");

1421

}

1422

/* Raise privileges even more */

1423

errno = 0;

1424

ret = setuid(0);

1425

if(ret == -1){

1426

perror_plus("setuid");

1427

}

1428

/* Set group */

1429

errno = 0;

1430

ret = setgid(0);

1431

if(ret == -1){

1432

perror_plus("setgid");

1433

}

1434

/* Reset supplementary groups */

1435

errno = 0;

1436

ret = setgroups(0, NULL);

1437

if(ret == -1){

1438

perror_plus("setgroups");

1439

}

1440

dup2(devnull, STDIN_FILENO);

1441

close(devnull);

1442

dup2(STDERR_FILENO, STDOUT_FILENO);

1443

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

1444

if(ret == -1){

1445

perror_plus("setenv");

1446

_exit(EX_OSERR);

1447

}

1448

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

1449

if(ret == -1){

1450

perror_plus("setenv");

1451

_exit(EX_OSERR);

1452

}

1453

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

1454

if(ret == -1){

1455

perror_plus("setenv");

1456

_exit(EX_OSERR);

1457

}

1458

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

1459

if(ret == -1){

1460

perror_plus("setenv");

1461

_exit(EX_OSERR);

1462

}

1463

char *delaystring;

1464

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

1465

if(ret == -1){

1466

perror_plus("asprintf");

1467

_exit(EX_OSERR);

1468

}

1469

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

1470

if(ret == -1){

1471

free(delaystring);

1472

perror_plus("setenv");

1473

_exit(EX_OSERR);

1474

}

2173

1475

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;

2242

} 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);

2262

}

2263

2264

__attribute__((nonnull, warn_unused_result))

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

2268

int ret;

2269

struct ifreq network;

2270

unsigned int if_index = if_nametoindex(interface);

2271

if(if_index == 0){

2272

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

2273

errno = old_errno;

2274

return ENXIO;

2275

}

2276

2277

if(quit_now){

2278

errno = old_errno;

2279

return EINTR;

2280

}

2281

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);

2360

if(ret == -1){

2361

perror_plus("close");

2362

}

2363

2364

if(ret_setflags == -1){

2365

errno = ioctl_errno;

2366

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2367

errno = old_errno;

2368

return ioctl_errno;

2369

}

2370

} else if(debug){

2371

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

2372

interface);

2373

}

2374

2375

/* Sleep checking until interface is running.

2376

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)){

2379

break;

2380

}

2381

struct timespec sleeptime = { .tv_nsec = 250000000 };

2382

ret = nanosleep(&sleeptime, NULL);

2383

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

2384

perror_plus("nanosleep");

2385

}

2386

}

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;

2401

}

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);

2449

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);

2462

}

2463

2464

errno = old_errno;

2465

return 0;

1476

if(connect_to != NULL){

1477

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

1478

if(ret == -1){

1479

perror_plus("setenv");

1480

_exit(EX_OSERR);

1481

}

1482

}

1483

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

1484

perror_plus("execl");

1485

_exit(EXIT_FAILURE);

1486

}

1487

} else {

1488

int status;

1489

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

1490

perror_plus("waitpid");

1491

free(fullname);

1492

continue;

1493

}

1494

if(WIFEXITED(status)){

1495

if(WEXITSTATUS(status) != 0){

1496

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

1497

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

1498

WEXITSTATUS(status));

1499

free(fullname);

1500

continue;

1501

}

1502

} else if(WIFSIGNALED(status)){

1503

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

1504

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

1505

WTERMSIG(status));

1506

free(fullname);

1507

continue;

1508

} else {

1509

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

1510

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

1511

free(fullname);

1512

continue;

1513

}

1514

}

1515

free(fullname);

1516

if(debug){

1517

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

1518

direntry->d_name);

1519

}

1520

}

1521

close(devnull);

1522

}

1523

return true;

2466

1524

}

2467

1525

2468

1526

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

1527

AvahiSServiceBrowser *sb = NULL;

2483

error_t ret_errno;

1528

int error;

2484

1529

int ret;

2485

1530

intmax_t tmpmax;

2486

1531

char *tmp;

2487

1532

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;

1533

const char *interface = "";

1534

struct ifreq network;

1535

int sd = -1;

1536

bool take_down_interface = false;

1537

uid_t uid;

1538

gid_t gid;

1539

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

1540

bool tempdir_created = false;

2493

1541

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2494

1542

const char *seckey = PATHDIR "/" SECKEY;

2495

1543

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

1544

2503

1545

bool gnutls_initialized = false;

2504

1546

bool gpgme_initialized = false;

2550

1592

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

2551

1593

.arg = "FILE",

2552

1594

.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 },

1595

.group = 2 },

2570

1596

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

2571

1597

.arg = "BITS",

2572

1598

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

2573

1599

" Diffie-Hellman key exchange",

2574

1600

.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

1601

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

2581

1602

.arg = "STRING",

2582

1603

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

2616

1637

connect_to = arg;

2617

1638

break;

2618

1639

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

}

1640

interface = arg;

2624

1641

break;

2625

1642

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

2626

1643

seckey = arg;

2628

1645

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

2629

1646

pubkey = arg;

2630

1647

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

1648

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

2642

1649

errno = 0;

2643

1650

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

2647

1654

}

2648

1655

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

2649

1656

break;

2650

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

2651

dh_params_file = arg;

2652

break;

2653

1657

case 130: /* --priority */

2654

1658

mc.priority = arg;

2655

1659

break;

2678

1682

argp_state_help(state, state->out_stream,

2679

1683

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2680

1684

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

2682

1685

case -3: /* --usage */

2683

1686

argp_state_help(state, state->out_stream,

2684

1687

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

2686

1688

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

2687

1689

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

2688

1690

exit(argp_err_exit_status);

2697

1699

.args_doc = "",

2698

1700

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

2699

1701

" 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){

1702

ret = argp_parse(&argp, argc, argv,

1703

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1704

switch(ret){

2703

1705

case 0:

2704

1706

break;

2705

1707

case ENOMEM:

2706

1708

default:

2707

errno = ret_errno;

1709

errno = ret;

2708

1710

perror_plus("argp_parse");

2709

1711

exitcode = EX_OSERR;

2710

1712

goto end;

2713

1715

goto end;

2714

1716

}

2715

1717

}

2716

1718

2717

1719

{

2718

1720

/* Work around Debian bug #633582:

2719

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

1721

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

2720

1722

2721

/* Re-raise privileges */

2722

ret = raise_privileges();

2723

if(ret != 0){

2724

errno = ret;

2725

perror_plus("Failed to raise privileges");

1723

/* Re-raise priviliges */

1724

errno = 0;

1725

ret = seteuid(0);

1726

if(ret == -1){

1727

perror_plus("seteuid");

2726

1728

} else {

2727

1729

struct stat st;

2728

1730

2743

1745

}

2744

1746

}

2745

1747

}

2746

close(seckey_fd);

1748

TEMP_FAILURE_RETRY(close(seckey_fd));

2747

1749

}

2748

1750

}

2749

1751

2750

1752

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

2751

1753

int pubkey_fd = open(pubkey, O_RDONLY);

2752

1754

if(pubkey_fd == -1){

2764

1766

}

2765

1767

}

2766

1768

}

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

1769

TEMP_FAILURE_RETRY(close(pubkey_fd));

1770

}

1771

}

1772

2793

1773

/* 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;

1774

errno = 0;

1775

ret = seteuid(uid);

1776

if(ret == -1){

1777

perror_plus("seteuid");

2815

1778

}

2816

1779

}

2817

1780

}

2818

1781

2819

1782

/* Run network hooks */

2820

{

2821

if(mc.interfaces != NULL){

2822

interfaces_hooks = malloc(mc.interfaces_size);

2823

if(interfaces_hooks == NULL){

2824

perror_plus("malloc");

2825

goto end;

2826

}

2827

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

2828

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

2829

}

2830

run_network_hooks("start", interfaces_hooks != NULL ?

2831

interfaces_hooks : "", delay);

1783

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

1784

goto end;

2832

1785

}

2833

1786

2834

1787

if(not debug){

2835

1788

avahi_set_log_function(empty_log);

2836

1789

}

2837

1790

1791

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

1792

struct dirent **direntries;

1793

/* First look for interfaces that are up */

1794

ret = scandir(sys_class_net, &direntries, up_interface,

1795

alphasort);

1796

if(ret == 0){

1797

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

1798

free(direntries);

1799

ret = scandir(sys_class_net, &direntries, good_interface,

1800

alphasort);

1801

}

1802

if(ret >= 1){

1803

/* Pick the first interface returned */

1804

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

1805

if(debug){

1806

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

1807

}

1808

if(interface == NULL){

1809

perror_plus("malloc");

1810

free(direntries);

1811

exitcode = EXIT_FAILURE;

1812

goto end;

1813

}

1814

free(direntries);

1815

} else {

1816

free(direntries);

1817

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

1818

exitcode = EXIT_FAILURE;

1819

goto end;

1820

}

1821

}

1822

2838

1823

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

2839

1824

from the signal handler */

2840

1825

/* Initialize the pseudo-RNG for Avahi */

2841

1826

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

2842

simple_poll = avahi_simple_poll_new();

2843

if(simple_poll == NULL){

1827

mc.simple_poll = avahi_simple_poll_new();

1828

if(mc.simple_poll == NULL){

2844

1829

fprintf_plus(stderr,

2845

1830

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

2846

1831

exitcode = EX_UNAVAILABLE;

2910

1895

}

2911

1896

}

2912

1897

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;

1898

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

1899

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

1900

if_index = (AvahiIfIndex) if_nametoindex(interface);

1901

if(if_index == 0){

1902

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

1903

exitcode = EX_UNAVAILABLE;

1904

goto end;

1905

}

1906

1907

if(quit_now){

1908

goto end;

1909

}

1910

1911

/* Re-raise priviliges */

1912

errno = 0;

1913

ret = seteuid(0);

1914

if(ret == -1){

1915

perror_plus("seteuid");

1916

}

1917

1918

#ifdef __linux__

1919

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1920

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

1921

ret = klogctl(8, NULL, 5);

1922

bool restore_loglevel = true;

1923

if(ret == -1){

1924

restore_loglevel = false;

1925

perror_plus("klogctl");

1926

}

1927

#endif /* __linux__ */

1928

1929

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1930

if(sd < 0){

1931

perror_plus("socket");

1932

exitcode = EX_OSERR;

1933

#ifdef __linux__

1934

if(restore_loglevel){

1935

ret = klogctl(7, NULL, 0);

1936

if(ret == -1){

1937

perror_plus("klogctl");

1938

}

1939

}

1940

#endif /* __linux__ */

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

strcpy(network.ifr_name, interface);

1950

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

1951

if(ret == -1){

1952

perror_plus("ioctl SIOCGIFFLAGS");

1953

#ifdef __linux__

1954

if(restore_loglevel){

1955

ret = klogctl(7, NULL, 0);

1956

if(ret == -1){

1957

perror_plus("klogctl");

1958

}

1959

}

1960

#endif /* __linux__ */

1961

exitcode = EX_OSERR;

1962

/* Lower privileges */

1963

errno = 0;

1964

ret = seteuid(uid);

1965

if(ret == -1){

1966

perror_plus("seteuid");

1967

}

1968

goto end;

1969

}

1970

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

1971

network.ifr_flags |= IFF_UP;

1972

take_down_interface = true;

1973

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

1974

if(ret == -1){

1975

take_down_interface = false;

1976

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1977

exitcode = EX_OSERR;

1978

#ifdef __linux__

1979

if(restore_loglevel){

1980

ret = klogctl(7, NULL, 0);

1981

if(ret == -1){

1982

perror_plus("klogctl");

2964

1983

}

2965

1984

}

1985

#endif /* __linux__ */

1986

/* Lower privileges */

1987

errno = 0;

1988

ret = seteuid(uid);

1989

if(ret == -1){

1990

perror_plus("seteuid");

1991

}

1992

goto end;

1993

}

1994

}

1995

/* Sleep checking until interface is running.

1996

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

1997

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

1998

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

1999

if(ret == -1){

2000

perror_plus("ioctl SIOCGIFFLAGS");

2001

} else if(network.ifr_flags & IFF_RUNNING){

2966

2002

break;

2967

2003

}

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);

2004

struct timespec sleeptime = { .tv_nsec = 250000000 };

2005

ret = nanosleep(&sleeptime, NULL);

2006

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

2007

perror_plus("nanosleep");

2008

}

2009

}

2010

if(not take_down_interface){

2011

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

2012

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

2013

if(ret == -1){

2014

perror_plus("close");

2015

}

2016

}

2017

#ifdef __linux__

2018

if(restore_loglevel){

2019

/* Restores kernel loglevel to default */

2020

ret = klogctl(7, NULL, 0);

2021

if(ret == -1){

2022

perror_plus("klogctl");

2023

}

2024

}

2025

#endif /* __linux__ */

2026

/* Lower privileges */

2027

errno = 0;

2028

/* Lower privileges */

2029

ret = seteuid(uid);

2030

if(ret == -1){

2031

perror_plus("seteuid");

2032

}

2996

2033

}

2997

2034

2998

2035

if(quit_now){

2999

2036

goto end;

3000

2037

}

3001

2038

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

2039

ret = init_gnutls_global(pubkey, seckey);

3009

2040

if(ret == -1){

3010

2041

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

3011

2042

exitcode = EX_UNAVAILABLE;

3018

2049

goto end;

3019

2050

}

3020

2051

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){

2052

if(mkdtemp(tempdir) == NULL){

3031

2053

perror_plus("mkdtemp");

3032

2054

goto end;

3033

2055

}

2056

tempdir_created = true;

3034

2057

3035

2058

if(quit_now){

3036

2059

goto end;

3037

2060

}

3038

2061

3039

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

2062

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

3040

2063

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

3041

2064

exitcode = EX_UNAVAILABLE;

3042

2065

goto end;

3052

2075

/* Connect directly, do not use Zeroconf */

3053

2076

/* (Mainly meant for debugging) */

3054

2077

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

3055

3056

2078

if(address == NULL){

3057

2079

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

3058

2080

exitcode = EX_USAGE;

3063

2085

goto end;

3064

2086

}

3065

2087

3066

in_port_t port;

2088

uint16_t port;

3067

2089

errno = 0;

3068

2090

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

3069

2091

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

3070

or tmpmax != (in_port_t)tmpmax){

2092

or tmpmax != (uint16_t)tmpmax){

3071

2093

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

3072

2094

exitcode = EX_USAGE;

3073

2095

goto end;

3074

2096

}

3075

2097

3076

2098

if(quit_now){

3077

2099

goto end;

3078

2100

}

3079

2101

3080

port = (in_port_t)tmpmax;

2102

port = (uint16_t)tmpmax;

3081

2103

*address = '\0';

3082

2104

/* Colon in address indicates IPv6 */

3083

2105

int af;

3099

2121

}

3100

2122

3101

2123

while(not quit_now){

3102

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

3103

&mc);

2124

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

3104

2125

if(quit_now or ret == 0){

3105

2126

break;

3106

2127

}

3108

2129

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

3109

2130

(int)retry_interval);

3110

2131

}

3111

sleep((unsigned int)retry_interval);

2132

sleep((int)retry_interval);

3112

2133

}

3113

2134

3114

if(not quit_now){

2135

if (not quit_now){

3115

2136

exitcode = EXIT_SUCCESS;

3116

2137

}

3117

2138

3132

2153

config.publish_domain = 0;

3133

2154

3134

2155

/* Allocate a new server */

3135

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3136

&config, NULL, NULL, &ret);

2156

mc.server = avahi_server_new(avahi_simple_poll_get

2157

(mc.simple_poll), &config, NULL,

2158

NULL, &error);

3137

2159

3138

2160

/* Free the Avahi configuration data */

3139

2161

avahi_server_config_free(&config);

3142

2164

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

3143

2165

if(mc.server == NULL){

3144

2166

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

3145

avahi_strerror(ret));

2167

avahi_strerror(error));

3146

2168

exitcode = EX_UNAVAILABLE;

3147

2169

goto end;

3148

2170

}

3154

2176

/* Create the Avahi service browser */

3155

2177

sb = avahi_s_service_browser_new(mc.server, if_index,

3156

2178

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3157

NULL, 0, browse_callback,

3158

(void *)&mc);

2179

NULL, 0, browse_callback, NULL);

3159

2180

if(sb == NULL){

3160

2181

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

3161

2182

avahi_strerror(avahi_server_errno(mc.server)));

3172

2193

if(debug){

3173

2194

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

3174

2195

}

3175

3176

ret = avahi_loop_with_timeout(simple_poll,

3177

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

2196

2197

ret = avahi_loop_with_timeout(mc.simple_poll,

2198

(int)(retry_interval * 1000));

3178

2199

if(debug){

3179

2200

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

3180

2201

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

3183

2204

end:

3184

2205

3185

2206

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

}

2207

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

3193

2208

}

3194

2209

3195

2210

/* Cleanup things */

3196

free(mc.interfaces);

3197

3198

2211

if(sb != NULL)

3199

2212

avahi_s_service_browser_free(sb);

3200

2213

3201

2214

if(mc.server != NULL)

3202

2215

avahi_server_free(mc.server);

3203

2216

3204

if(simple_poll != NULL)

3205

avahi_simple_poll_free(simple_poll);

2217

if(mc.simple_poll != NULL)

2218

avahi_simple_poll_free(mc.simple_poll);

3206

2219

3207

2220

if(gnutls_initialized){

3208

2221

gnutls_certificate_free_credentials(mc.cred);

2222

gnutls_global_deinit();

3209

2223

gnutls_dh_params_deinit(mc.dh_params);

3210

2224

}

3211

2225

3219

2233

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

3220

2234

while(mc.current_server != NULL){

3221

2235

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

2236

free(mc.current_server);

3231

2237

mc.current_server = next;

3232

2238

}

3233

2239

}

3234

2240

3235

/* Re-raise privileges */

2241

/* Run network hooks */

2242

run_network_hooks("stop", interface, delay);

2243

2244

/* Re-raise priviliges */

3236

2245

{

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

}

2246

errno = 0;

2247

ret = seteuid(0);

2248

if(ret == -1){

2249

perror_plus("seteuid");

3264

2250

}

3265

2251

3266

ret = lower_privileges_permanently();

3267

if(ret != 0){

3268

errno = ret;

3269

perror_plus("Failed to lower privileges permanently");

2252

/* Take down the network interface */

2253

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

2254

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

2255

if(ret == -1){

2256

perror_plus("ioctl SIOCGIFFLAGS");

2257

} else if(network.ifr_flags & IFF_UP){

2258

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

2259

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

2260

if(ret == -1){

2261

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2262

}

2263

}

2264

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

2265

if(ret == -1){

2266

perror_plus("close");

2267

}

3270

2268

}

3271

2269

}

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){

2270

/* Lower privileges permanently */

2271

errno = 0;

2272

ret = setuid(uid);

2273

if(ret == -1){

2274

perror_plus("setuid");

2275

}

2276

2277

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

2278

if(tempdir_created){

3278

2279

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){

2280

struct dirent *direntry = NULL;

2281

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

2282

alphasort);

2283

if (numentries > 0){

3292

2284

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);

2285

direntry = direntries[i];

2286

char *fullname = NULL;

2287

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

2288

direntry->d_name);

2289

if(ret < 0){

2290

perror_plus("asprintf");

2291

continue;

2292

}

2293

ret = remove(fullname);

2294

if(ret == -1){

2295

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

2296

strerror(errno));

2297

}

2298

free(fullname);

2299

}

2300

}

2301

2302

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

2303

free(direntries);

2304

if (numentries == -1){

2305

perror_plus("scandir");

2306

}

2307

ret = rmdir(tempdir);

2308

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

2309

perror_plus("rmdir");

2310

}

3333

2311

}

3334

2312

3335

2313

if(quit_now){