/mandos/release : revision 237.7.512

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

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*

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* Everything else is

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*

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

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

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

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

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*

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

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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* along with this program. If not, see

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

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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

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

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stdout, ferror(), remove() */

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

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stdout, ferror() */

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

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

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

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strtof(), abort() */

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

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

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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sockaddr_in6, PF_INET6,

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

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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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strtoimax() */

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

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

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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program_invocation_short_name */

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

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

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*/

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

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

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unlinkat() */

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

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

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

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argp_state, struct argp,

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#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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uint16_t port;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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AvahiSimplePoll *simple_poll;

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

217

__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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233

}

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

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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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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

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

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if(new_server == NULL){

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.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;

253

}

254

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

259

#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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if (mc.current_server == NULL){

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if(*current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

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

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*current_server = new_server;

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} else {

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

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new_server->next = *current_server;

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

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new_server->prev->next = new_server;

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mc.current_server->prev = new_server;

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}

233

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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(*current_server)->prev = new_server;

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}

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return true;

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}

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

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__attribute__((warn_unused_result))

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. */

296

__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

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int old_errno = errno;

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int ret = raise_privileges();

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if(ret != 0){

301

errno = old_errno;

302

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 */

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__attribute__((warn_unused_result))

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int lower_privileges(void){

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int old_errno = errno;

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int ret = 0;

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

317

ret = errno;

318

}

319

errno = old_errno;

320

return ret;

321

}

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/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

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}

331

errno = old_errno;

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return ret;

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}

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/*

242

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* Initialize GPGME.

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*/

244

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

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const char *tempdir){

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__attribute__((nonnull, warn_unused_result))

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static bool init_gpgme(const char * const seckey,

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const char * const pubkey,

341

const char * const tempdir,

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mandos_context *mc){

246

343

gpgme_error_t rc;

247

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gpgme_engine_info_t engine_info;

248

345

249

250

346

/*

251

347

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

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*/

253

bool import_key(const char *filename){

349

bool import_key(const char * const filename){

254

350

int ret;

255

351

int fd;

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gpgme_data_t pgp_data;

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return false;

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}

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

361

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

362

do {

363

{

364

time_t currtime = time(NULL);

365

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

366

struct tm tm;

367

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

368

perror_plus("gmtime_r");

369

break;

370

}

371

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

372

break;

373

}

374

if(debug){

375

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

376

}

377

} else {

378

if(debug){

379

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

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

time_t keytime = keystat.st_mtim.tv_sec;

400

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

401

perror_plus("stime");

402

}

403

ret = lower_privileges();

404

if(ret != 0){

405

errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

264

410

rc = gpgme_data_new_from_fd(&pgp_data, fd);

265

411

if(rc != GPG_ERR_NO_ERROR){

266

412

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

268

414

return false;

269

415

}

270

416

271

rc = gpgme_op_import(mc.ctx, pgp_data);

417

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

272

418

if(rc != GPG_ERR_NO_ERROR){

273

419

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

274

420

gpgme_strsource(rc), gpgme_strerror(rc));

275

421

return false;

276

422

}

423

{

424

gpgme_import_result_t import_result

425

= gpgme_op_import_result(mc->ctx);

426

if((import_result->imported < 1

427

or import_result->not_imported > 0)

428

and import_result->unchanged == 0){

429

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

430

fprintf_plus(stderr,

431

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

432

import_result->considered);

433

fprintf_plus(stderr,

434

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

435

import_result->no_user_id);

436

fprintf_plus(stderr,

437

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

438

import_result->imported);

439

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

440

import_result->imported_rsa);

441

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

442

import_result->unchanged);

443

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

444

import_result->new_user_ids);

445

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

446

import_result->new_sub_keys);

447

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

448

import_result->new_signatures);

449

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

450

import_result->new_revocations);

451

fprintf_plus(stderr,

452

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

453

import_result->secret_read);

454

fprintf_plus(stderr,

455

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

456

import_result->secret_imported);

457

fprintf_plus(stderr,

458

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

459

import_result->secret_unchanged);

460

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

461

import_result->not_imported);

462

for(gpgme_import_status_t import_status

463

= import_result->imports;

464

import_status != NULL;

465

import_status = import_status->next){

466

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

467

import_status->fpr);

468

if(import_status->result != GPG_ERR_NO_ERROR){

469

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

470

gpgme_strsource(import_status->result),

471

gpgme_strerror(import_status->result));

472

}

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_NEW

476

? "The key was new.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_UID

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SIG

484

? "The key contained new signatures.\n"

485

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

486

fprintf_plus(stderr,

487

import_status->status & GPGME_IMPORT_SUBKEY

488

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

489

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

490

fprintf_plus(stderr,

491

import_status->status & GPGME_IMPORT_SECRET

492

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

493

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

494

}

495

return false;

496

}

497

}

277

498

278

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

499

ret = close(fd);

279

500

if(ret == -1){

280

501

perror_plus("close");

281

502

}

318

539

}

319

540

320

541

/* Create new GPGME "context" */

321

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

542

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

322

543

if(rc != GPG_ERR_NO_ERROR){

323

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

324

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

325

gpgme_strerror(rc));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

326

546

return false;

327

547

}

328

548

337

557

* Decrypt OpenPGP data.

338

558

* Returns -1 on error

339

559

*/

560

__attribute__((nonnull, warn_unused_result))

340

561

static ssize_t pgp_packet_decrypt(const char *cryptotext,

341

562

size_t crypto_size,

342

char **plaintext){

563

char **plaintext,

564

mandos_context *mc){

343

565

gpgme_data_t dh_crypto, dh_plain;

344

566

gpgme_error_t rc;

345

567

ssize_t ret;

362

584

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

363

585

rc = gpgme_data_new(&dh_plain);

364

586

if(rc != GPG_ERR_NO_ERROR){

365

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

366

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

587

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

367

588

gpgme_strsource(rc), gpgme_strerror(rc));

368

589

gpgme_data_release(dh_crypto);

369

590

return -1;

371

592

372

593

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

373

594

data buffer */

374

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

595

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

375

596

if(rc != GPG_ERR_NO_ERROR){

376

597

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

377

598

gpgme_strsource(rc), gpgme_strerror(rc));

378

599

plaintext_length = -1;

379

600

if(debug){

380

601

gpgme_decrypt_result_t result;

381

result = gpgme_op_decrypt_result(mc.ctx);

602

result = gpgme_op_decrypt_result(mc->ctx);

382

603

if(result == NULL){

383

604

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

384

605

} else {

385

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

386

result->unsupported_algorithm);

387

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

388

result->wrong_key_usage);

606

if(result->unsupported_algorithm != NULL) {

607

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

608

result->unsupported_algorithm);

609

}

610

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

611

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

389

612

if(result->file_name != NULL){

390

613

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

391

614

}

392

gpgme_recipient_t recipient;

393

recipient = result->recipients;

394

while(recipient != NULL){

615

616

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

617

r = r->next){

395

618

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

396

gpgme_pubkey_algo_name

397

(recipient->pubkey_algo));

398

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

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

399

621

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

400

recipient->status == GPG_ERR_NO_SECKEY

401

? "No" : "Yes");

402

recipient = recipient->next;

622

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

403

623

}

404

624

}

405

625

}

461

681

return plaintext_length;

462

682

}

463

683

464

static const char * safer_gnutls_strerror(int value){

465

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

466

-Wunreachable-code */

467

if(ret == NULL)

468

ret = "(unknown)";

469

return ret;

684

__attribute__((warn_unused_result, const))

685

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

686

if(str == NULL)

687

return "(unknown)";

688

return str;

689

}

690

691

__attribute__((warn_unused_result))

692

static const char *safer_gnutls_strerror(int value){

693

const char *ret = gnutls_strerror(value);

694

return safe_string(ret);

470

695

}

471

696

472

697

/* GnuTLS log function callback */

698

__attribute__((nonnull))

473

699

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

474

700

const char* string){

475

701

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

476

702

}

477

703

704

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

478

705

static int init_gnutls_global(const char *pubkeyfilename,

479

const char *seckeyfilename){

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

mandos_context *mc){

480

709

int ret;

481

710

482

711

if(debug){

483

712

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

484

713

}

485

714

486

ret = gnutls_global_init();

487

if(ret != GNUTLS_E_SUCCESS){

488

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

489

safer_gnutls_strerror(ret));

490

return -1;

491

}

492

493

715

if(debug){

494

716

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

495

717

* - GnuTLS manual

499

721

}

500

722

501

723

/* OpenPGP credentials */

502

ret = gnutls_certificate_allocate_credentials(&mc.cred);

724

ret = gnutls_certificate_allocate_credentials(&mc->cred);

503

725

if(ret != GNUTLS_E_SUCCESS){

504

726

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

505

727

safer_gnutls_strerror(ret));

506

gnutls_global_deinit();

507

728

return -1;

508

729

}

509

730

510

731

if(debug){

511

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

512

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

732

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

733

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

513

734

pubkeyfilename,

514

735

seckeyfilename);

515

736

}

516

737

738

#if GNUTLS_VERSION_NUMBER >= 0x030606

739

ret = gnutls_certificate_set_rawpk_key_file

740

(mc->cred, pubkeyfilename, seckeyfilename,

741

GNUTLS_X509_FMT_PEM, /* format */

742

NULL, /* pass */

743

/* key_usage */

744

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

745

NULL, /* names */

746

0, /* names_length */

747

/* privkey_flags */

748

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

749

0); /* pkcs11_flags */

750

#elif GNUTLS_VERSION_NUMBER < 0x030600

517

751

ret = gnutls_certificate_set_openpgp_key_file

518

(mc.cred, pubkeyfilename, seckeyfilename,

752

(mc->cred, pubkeyfilename, seckeyfilename,

519

753

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

520

757

if(ret != GNUTLS_E_SUCCESS){

521

758

fprintf_plus(stderr,

522

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

759

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

523

760

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

524

761

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

525

762

safer_gnutls_strerror(ret));

527

764

}

528

765

529

766

/* GnuTLS server initialization */

530

ret = gnutls_dh_params_init(&mc.dh_params);

767

ret = gnutls_dh_params_init(&mc->dh_params);

531

768

if(ret != GNUTLS_E_SUCCESS){

532

769

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

533

770

" initialization: %s\n",

534

771

safer_gnutls_strerror(ret));

535

772

goto globalfail;

536

773

}

537

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

538

if(ret != GNUTLS_E_SUCCESS){

539

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

540

safer_gnutls_strerror(ret));

541

goto globalfail;

542

}

543

544

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

774

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

775

if(dhparamsfilename != NULL){

776

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

777

do {

778

int dhpfile = open(dhparamsfilename, O_RDONLY);

779

if(dhpfile == -1){

780

perror_plus("open");

781

dhparamsfilename = NULL;

782

break;

783

}

784

size_t params_capacity = 0;

785

while(true){

786

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

787

(size_t)params.size,

788

(size_t)params_capacity);

789

if(params_capacity == 0){

790

perror_plus("incbuffer");

791

free(params.data);

792

params.data = NULL;

793

dhparamsfilename = NULL;

794

break;

795

}

796

ssize_t bytes_read = read(dhpfile,

797

params.data + params.size,

798

BUFFER_SIZE);

799

/* EOF */

800

if(bytes_read == 0){

801

break;

802

}

803

/* check bytes_read for failure */

804

if(bytes_read < 0){

805

perror_plus("read");

806

free(params.data);

807

params.data = NULL;

808

dhparamsfilename = NULL;

809

break;

810

}

811

params.size += (unsigned int)bytes_read;

812

}

813

ret = close(dhpfile);

814

if(ret == -1){

815

perror_plus("close");

816

}

817

if(params.data == NULL){

818

dhparamsfilename = NULL;

819

}

820

if(dhparamsfilename == NULL){

821

break;

822

}

823

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

824

GNUTLS_X509_FMT_PEM);

825

if(ret != GNUTLS_E_SUCCESS){

826

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

827

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

828

safer_gnutls_strerror(ret));

829

dhparamsfilename = NULL;

830

}

831

free(params.data);

832

} while(false);

833

}

834

if(dhparamsfilename == NULL){

835

if(mc->dh_bits == 0){

836

#if GNUTLS_VERSION_NUMBER < 0x030600

837

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

838

/* Try to read the private key file */

839

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

840

do {

841

int secfile = open(seckeyfilename, O_RDONLY);

842

if(secfile == -1){

843

perror_plus("open");

844

break;

845

}

846

size_t buffer_capacity = 0;

847

while(true){

848

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

849

(size_t)buffer.size,

850

(size_t)buffer_capacity);

851

if(buffer_capacity == 0){

852

perror_plus("incbuffer");

853

free(buffer.data);

854

buffer.data = NULL;

855

break;

856

}

857

ssize_t bytes_read = read(secfile,

858

buffer.data + buffer.size,

859

BUFFER_SIZE);

860

/* EOF */

861

if(bytes_read == 0){

862

break;

863

}

864

/* check bytes_read for failure */

865

if(bytes_read < 0){

866

perror_plus("read");

867

free(buffer.data);

868

buffer.data = NULL;

869

break;

870

}

871

buffer.size += (unsigned int)bytes_read;

872

}

873

close(secfile);

874

} while(false);

875

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

876

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

877

if(buffer.data != NULL){

878

{

879

gnutls_openpgp_privkey_t privkey = NULL;

880

ret = gnutls_openpgp_privkey_init(&privkey);

881

if(ret != GNUTLS_E_SUCCESS){

882

fprintf_plus(stderr, "Error initializing OpenPGP key"

883

" structure: %s",

884

safer_gnutls_strerror(ret));

885

free(buffer.data);

886

buffer.data = NULL;

887

} else {

888

ret = gnutls_openpgp_privkey_import

889

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

890

if(ret != GNUTLS_E_SUCCESS){

891

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

892

safer_gnutls_strerror(ret));

893

privkey = NULL;

894

}

895

free(buffer.data);

896

buffer.data = NULL;

897

if(privkey != NULL){

898

/* Use private key to suggest an appropriate

899

sec_param */

900

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

901

gnutls_openpgp_privkey_deinit(privkey);

902

if(debug){

903

fprintf_plus(stderr, "This OpenPGP key implies using"

904

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

905

safe_string(gnutls_sec_param_get_name

906

(sec_param)));

907

}

908

}

909

}

910

}

911

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

912

/* Err on the side of caution */

913

sec_param = GNUTLS_SEC_PARAM_ULTRA;

914

if(debug){

915

fprintf_plus(stderr, "Falling back to security parameter"

916

" \"%s\"\n",

917

safe_string(gnutls_sec_param_get_name

918

(sec_param)));

919

}

920

}

921

}

922

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

923

if(uret != 0){

924

mc->dh_bits = uret;

925

if(debug){

926

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

927

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

928

safe_string(gnutls_sec_param_get_name

929

(sec_param)),

930

mc->dh_bits);

931

}

932

} else {

933

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

934

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

935

safe_string(gnutls_sec_param_get_name

936

(sec_param)),

937

safer_gnutls_strerror(ret));

938

goto globalfail;

939

}

940

#endif

941

} else { /* dh_bits != 0 */

942

if(debug){

943

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

944

mc->dh_bits);

945

}

946

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

947

if(ret != GNUTLS_E_SUCCESS){

948

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

949

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

950

safer_gnutls_strerror(ret));

951

goto globalfail;

952

}

953

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

954

}

955

}

545

956

546

957

return 0;

547

958

548

959

globalfail:

549

960

550

gnutls_certificate_free_credentials(mc.cred);

551

gnutls_global_deinit();

552

gnutls_dh_params_deinit(mc.dh_params);

961

gnutls_certificate_free_credentials(mc->cred);

962

gnutls_dh_params_deinit(mc->dh_params);

553

963

return -1;

554

964

}

555

965

556

static int init_gnutls_session(gnutls_session_t *session){

966

__attribute__((nonnull, warn_unused_result))

967

static int init_gnutls_session(gnutls_session_t *session,

968

mandos_context *mc){

557

969

int ret;

558

970

/* GnuTLS session creation */

559

971

do {

560

ret = gnutls_init(session, GNUTLS_SERVER);

972

ret = gnutls_init(session, (GNUTLS_SERVER

973

#if GNUTLS_VERSION_NUMBER >= 0x030506

974

| GNUTLS_NO_TICKETS

975

#endif

976

#if GNUTLS_VERSION_NUMBER >= 0x030606

977

| GNUTLS_ENABLE_RAWPK

978

#endif

979

));

561

980

if(quit_now){

562

981

return -1;

563

982

}

571

990

{

572

991

const char *err;

573

992

do {

574

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

993

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

575

994

if(quit_now){

576

995

gnutls_deinit(*session);

577

996

return -1;

588

1007

589

1008

do {

590

1009

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

591

mc.cred);

1010

mc->cred);

592

1011

if(quit_now){

593

1012

gnutls_deinit(*session);

594

1013

return -1;

604

1023

/* ignore client certificate if any. */

605

1024

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

606

1025

607

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

608

609

1026

return 0;

610

1027

}

611

1028

613

1030

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

614

1031

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

615

1032

1033

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

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool add_delete_local_route(const bool add,

1036

const char *address,

1037

AvahiIfIndex if_index){

1038

int ret;

1039

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

1040

char add_arg[] = "add";

1041

char delete_arg[] = "delete";

1042

char debug_flag[] = "--debug";

1043

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1044

if(pluginhelperdir == NULL){

1045

if(debug){

1046

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1047

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

1048

}

1049

return false;

1050

}

1051

1052

char interface[IF_NAMESIZE];

1053

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

1054

perror_plus("if_indextoname");

1055

return false;

1056

}

1057

1058

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

1059

if(devnull == -1){

1060

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

1061

return false;

1062

}

1063

pid_t pid = fork();

1064

if(pid == 0){

1065

/* Child */

1066

/* Raise privileges */

1067

errno = raise_privileges_permanently();

1068

if(errno != 0){

1069

perror_plus("Failed to raise privileges");

1070

/* _exit(EX_NOPERM); */

1071

} else {

1072

/* Set group */

1073

errno = 0;

1074

ret = setgid(0);

1075

if(ret == -1){

1076

perror_plus("setgid");

1077

_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

_exit(EX_NOPERM);

1085

}

1086

}

1087

ret = dup2(devnull, STDIN_FILENO);

1088

if(ret == -1){

1089

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

1090

_exit(EX_OSERR);

1091

}

1092

ret = close(devnull);

1093

if(ret == -1){

1094

perror_plus("close");

1095

_exit(EX_OSERR);

1096

}

1097

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1098

if(ret == -1){

1099

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

1100

_exit(EX_OSERR);

1101

}

1102

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

1103

O_RDONLY

1104

| O_DIRECTORY

1105

| O_PATH

1106

| O_CLOEXEC));

1107

if(helperdir_fd == -1){

1108

perror_plus("open");

1109

_exit(EX_UNAVAILABLE);

1110

}

1111

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

1112

helper, O_RDONLY));

1113

if(helper_fd == -1){

1114

perror_plus("openat");

1115

close(helperdir_fd);

1116

_exit(EX_UNAVAILABLE);

1117

}

1118

close(helperdir_fd);

1119

#ifdef __GNUC__

1120

#pragma GCC diagnostic push

1121

#pragma GCC diagnostic ignored "-Wcast-qual"

1122

#endif

1123

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

1124

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

1125

interface, debug ? debug_flag : NULL, NULL },

1126

environ) == -1){

1127

#ifdef __GNUC__

1128

#pragma GCC diagnostic pop

1129

#endif

1130

perror_plus("fexecve");

1131

_exit(EXIT_FAILURE);

1132

}

1133

}

1134

if(pid == -1){

1135

perror_plus("fork");

1136

return false;

1137

}

1138

int status;

1139

pid_t pret = -1;

1140

errno = 0;

1141

do {

1142

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

1143

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

1144

int errno_raising = 0;

1145

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

1146

errno_raising = errno;

1147

perror_plus("Failed to raise privileges in order to"

1148

" kill helper program");

1149

}

1150

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

1151

perror_plus("kill");

1152

}

1153

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

1154

perror_plus("Failed to lower privileges after killing"

1155

" helper program");

1156

}

1157

return false;

1158

}

1159

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

1160

if(pret == -1){

1161

perror_plus("waitpid");

1162

return false;

1163

}

1164

if(WIFEXITED(status)){

1165

if(WEXITSTATUS(status) != 0){

1166

fprintf_plus(stderr, "Error: iprouteadddel exited"

1167

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

1168

return false;

1169

}

1170

return true;

1171

}

1172

if(WIFSIGNALED(status)){

1173

fprintf_plus(stderr, "Error: iprouteadddel died by"

1174

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

1175

return false;

1176

}

1177

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

1178

return false;

1179

}

1180

1181

__attribute__((nonnull, warn_unused_result))

1182

static bool add_local_route(const char *address,

1183

AvahiIfIndex if_index){

1184

if(debug){

1185

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

1186

}

1187

return add_delete_local_route(true, address, if_index);

1188

}

1189

1190

__attribute__((nonnull, warn_unused_result))

1191

static bool delete_local_route(const char *address,

1192

AvahiIfIndex if_index){

1193

if(debug){

1194

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

1195

}

1196

return add_delete_local_route(false, address, if_index);

1197

}

1198

616

1199

/* Called when a Mandos server is found */

617

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

1200

__attribute__((nonnull, warn_unused_result))

1201

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

618

1202

AvahiIfIndex if_index,

619

int af){

1203

int af, mandos_context *mc){

620

1204

int ret, tcp_sd = -1;

621

1205

ssize_t sret;

622

union {

623

struct sockaddr_in in;

624

struct sockaddr_in6 in6;

625

} to;

1206

struct sockaddr_storage to;

626

1207

char *buffer = NULL;

627

1208

char *decrypted_buffer = NULL;

628

1209

size_t buffer_length = 0;

631

1212

int retval = -1;

632

1213

gnutls_session_t session;

633

1214

int pf; /* Protocol family */

1215

bool route_added = false;

634

1216

635

1217

errno = 0;

636

1218

652

1234

return -1;

653

1235

}

654

1236

655

ret = init_gnutls_session(&session);

1237

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

1238

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

1239

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

1240

bool match = false;

1241

{

1242

char *interface = NULL;

1243

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

1244

mc->interfaces_size,

1245

interface))){

1246

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

1247

match = true;

1248

break;

1249

}

1250

}

1251

}

1252

if(not match){

1253

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

1254

connect to the server */

1255

if(debug){

1256

char interface[IF_NAMESIZE];

1257

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

1258

perror_plus("if_indextoname");

1259

} else {

1260

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

1261

" \"%s\"\n",

1262

if_indextoname((unsigned int)if_index,

1263

interface));

1264

}

1265

}

1266

return -1;

1267

}

1268

}

1269

1270

ret = init_gnutls_session(&session, mc);

656

1271

if(ret != 0){

657

1272

return -1;

658

1273

}

659

1274

660

1275

if(debug){

661

1276

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

662

PRIu16 "\n", ip, port);

1277

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

663

1278

}

664

1279

665

tcp_sd = socket(pf, SOCK_STREAM, 0);

1280

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

666

1281

if(tcp_sd < 0){

667

1282

int e = errno;

668

1283

perror_plus("socket");

675

1290

goto mandos_end;

676

1291

}

677

1292

678

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

679

1293

if(af == AF_INET6){

680

to.in6.sin6_family = (sa_family_t)af;

681

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

1294

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

1295

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

1296

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

682

1297

} else { /* IPv4 */

683

to.in.sin_family = (sa_family_t)af;

684

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

1298

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

1299

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

1300

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

685

1301

}

686

1302

if(ret < 0 ){

687

1303

int e = errno;

696

1312

goto mandos_end;

697

1313

}

698

1314

if(af == AF_INET6){

699

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

700

-Wconversion and

701

-Wunreachable-code */

702

703

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

704

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

705

-Wunreachable-code*/

1315

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

1316

if(IN6_IS_ADDR_LINKLOCAL

1317

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

706

1318

if(if_index == AVAHI_IF_UNSPEC){

707

1319

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

708

1320

" incomplete without a network interface\n");

710

1322

goto mandos_end;

711

1323

}

712

1324

/* Set the network interface number as scope */

713

to.in6.sin6_scope_id = (uint32_t)if_index;

1325

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

714

1326

}

715

1327

} else {

716

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

717

-Wconversion and

718

-Wunreachable-code */

1328

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

719

1329

}

720

1330

721

1331

if(quit_now){

729

1339

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

730

1340

perror_plus("if_indextoname");

731

1341

} else {

732

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

733

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

1342

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

1343

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

734

1344

}

735

1345

} else {

736

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

737

ip, port);

1346

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

1347

ip, (uintmax_t)port);

738

1348

}

739

1349

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

740

1350

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

741

const char *pcret;

742

if(af == AF_INET6){

743

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

744

sizeof(addrstr));

745

} else {

746

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

747

sizeof(addrstr));

748

}

749

if(pcret == NULL){

750

perror_plus("inet_ntop");

751

} else {

752

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

753

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

754

}

755

}

756

}

757

758

if(quit_now){

759

errno = EINTR;

760

goto mandos_end;

761

}

762

763

if(af == AF_INET6){

764

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

765

} else {

766

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

767

}

768

if(ret < 0){

769

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

770

int e = errno;

771

perror_plus("connect");

772

errno = e;

773

}

774

goto mandos_end;

775

}

776

777

if(quit_now){

778

errno = EINTR;

779

goto mandos_end;

1351

if(af == AF_INET6){

1352

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

1353

sizeof(struct sockaddr_in6),

1354

addrstr, sizeof(addrstr), NULL, 0,

1355

NI_NUMERICHOST);

1356

} else {

1357

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

1358

sizeof(struct sockaddr_in),

1359

addrstr, sizeof(addrstr), NULL, 0,

1360

NI_NUMERICHOST);

1361

}

1362

if(ret == EAI_SYSTEM){

1363

perror_plus("getnameinfo");

1364

} else if(ret != 0) {

1365

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

1366

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

1367

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

1368

}

1369

}

1370

1371

if(quit_now){

1372

errno = EINTR;

1373

goto mandos_end;

1374

}

1375

1376

while(true){

1377

if(af == AF_INET6){

1378

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

1379

sizeof(struct sockaddr_in6));

1380

} else {

1381

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

1382

sizeof(struct sockaddr_in));

1383

}

1384

if(ret < 0){

1385

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

1386

and if_index != AVAHI_IF_UNSPEC

1387

and connect_to == NULL

1388

and not route_added and

1389

((af == AF_INET6 and not

1390

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1391

&to)->sin6_addr)))

1392

or (af == AF_INET and

1393

/* Not a a IPv4LL address */

1394

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

1395

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

1396

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

1397

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

1398

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

1399

connect to a Mandos server announced by Avahi on a server

1400

host with a global address. Work around this by retrying

1401

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

1402

1403

Avahi bug reference:

1404

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

1405

https://bugs.debian.org/587961

1406

*/

1407

if(debug){

1408

fprintf_plus(stderr, "Mandos server unreachable, trying"

1409

" direct route\n");

1410

}

1411

int e = errno;

1412

route_added = add_local_route(ip, if_index);

1413

if(route_added){

1414

continue;

1415

}

1416

errno = e;

1417

}

1418

if(errno != ECONNREFUSED or debug){

1419

int e = errno;

1420

perror_plus("connect");

1421

errno = e;

1422

}

1423

goto mandos_end;

1424

}

1425

1426

if(quit_now){

1427

errno = EINTR;

1428

goto mandos_end;

1429

}

1430

break;

780

1431

}

781

1432

782

1433

const char *out = mandos_protocol_version;

818

1469

goto mandos_end;

819

1470

}

820

1471

821

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

822

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1472

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

1473

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

1474

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

1475

gnutls_transport_set_ptr(session,

1476

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

823

1477

824

1478

if(quit_now){

825

1479

errno = EINTR;

930

1584

if(buffer_length > 0){

931

1585

ssize_t decrypted_buffer_size;

932

1586

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

933

&decrypted_buffer);

1587

&decrypted_buffer, mc);

934

1588

if(decrypted_buffer_size >= 0){

935

1589

1590

clearerr(stdout);

936

1591

written = 0;

937

1592

while(written < (size_t) decrypted_buffer_size){

938

1593

if(quit_now){

954

1609

}

955

1610

written += (size_t)ret;

956

1611

}

1612

ret = fflush(stdout);

1613

if(ret != 0){

1614

int e = errno;

1615

if(debug){

1616

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

1617

strerror(errno));

1618

}

1619

errno = e;

1620

goto mandos_end;

1621

}

957

1622

retval = 0;

958

1623

}

959

1624

}

962

1627

963

1628

mandos_end:

964

1629

{

1630

if(route_added){

1631

if(not delete_local_route(ip, if_index)){

1632

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

1633

" interface %d", ip, if_index);

1634

}

1635

}

965

1636

int e = errno;

966

1637

free(decrypted_buffer);

967

1638

free(buffer);

968

1639

if(tcp_sd >= 0){

969

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

1640

ret = close(tcp_sd);

970

1641

}

971

1642

if(ret == -1){

972

1643

if(e == 0){

997

1668

AVAHI_GCC_UNUSED AvahiStringList *txt,

998

1669

AVAHI_GCC_UNUSED AvahiLookupResultFlags

999

1670

flags,

1000

AVAHI_GCC_UNUSED void* userdata){

1001

assert(r);

1671

void *mc){

1672

if(r == NULL){

1673

return;

1674

}

1002

1675

1003

1676

/* Called whenever a service has been resolved successfully or

1004

1677

timed out */

1005

1678

1006

1679

if(quit_now){

1680

avahi_s_service_resolver_free(r);

1007

1681

return;

1008

1682

}

1009

1683

1013

1687

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

1014

1688

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

1015

1689

domain,

1016

avahi_strerror(avahi_server_errno(mc.server)));

1690

avahi_strerror(avahi_server_errno

1691

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

1017

1692

break;

1018

1693

1019

1694

case AVAHI_RESOLVER_FOUND:

1025

1700

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

1026

1701

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

1027

1702

}

1028

int ret = start_mandos_communication(ip, port, interface,

1029

avahi_proto_to_af(proto));

1703

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

1704

interface,

1705

avahi_proto_to_af(proto),

1706

mc);

1030

1707

if(ret == 0){

1031

avahi_simple_poll_quit(mc.simple_poll);

1708

avahi_simple_poll_quit(simple_poll);

1032

1709

} else {

1033

if(not add_server(ip, port, interface,

1034

avahi_proto_to_af(proto))){

1710

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

1711

avahi_proto_to_af(proto),

1712

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

1035

1713

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

1036

1714

" list\n", name);

1037

1715

}

1050

1728

const char *domain,

1051

1729

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1052

1730

flags,

1053

AVAHI_GCC_UNUSED void* userdata){

1054

assert(b);

1731

void *mc){

1732

if(b == NULL){

1733

return;

1734

}

1055

1735

1056

1736

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

1057

1737

is removed from the LAN */

1065

1745

case AVAHI_BROWSER_FAILURE:

1066

1746

1067

1747

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

1068

avahi_strerror(avahi_server_errno(mc.server)));

1069

avahi_simple_poll_quit(mc.simple_poll);

1748

avahi_strerror(avahi_server_errno

1749

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

1750

avahi_simple_poll_quit(simple_poll);

1070

1751

return;

1071

1752

1072

1753

case AVAHI_BROWSER_NEW:

1075

1756

the callback function is called the Avahi server will free the

1076

1757

resolver for us. */

1077

1758

1078

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

1079

name, type, domain, protocol, 0,

1080

resolve_callback, NULL) == NULL)

1759

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

1760

interface, protocol, name, type,

1761

domain, protocol, 0,

1762

resolve_callback, mc) == NULL)

1081

1763

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

1082

1764

" %s\n", name,

1083

avahi_strerror(avahi_server_errno(mc.server)));

1765

avahi_strerror(avahi_server_errno

1766

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

1084

1767

break;

1085

1768

1086

1769

case AVAHI_BROWSER_REMOVE:

1105

1788

signal_received = sig;

1106

1789

int old_errno = errno;

1107

1790

/* set main loop to exit */

1108

if(mc.simple_poll != NULL){

1109

avahi_simple_poll_quit(mc.simple_poll);

1791

if(simple_poll != NULL){

1792

avahi_simple_poll_quit(simple_poll);

1110

1793

}

1111

1794

errno = old_errno;

1112

1795

}

1113

1796

1797

__attribute__((nonnull, warn_unused_result))

1114

1798

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

1115

1799

int ret;

1800

int old_errno;

1116

1801

1117

1802

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

1118

1803

if(s < 0){

1804

old_errno = errno;

1119

1805

perror_plus("socket");

1806

errno = old_errno;

1120

1807

return false;

1121

1808

}

1122

strcpy(ifr->ifr_name, ifname);

1809

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

1810

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

1123

1811

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1124

1812

if(ret == -1){

1125

1813

if(debug){

1814

old_errno = errno;

1126

1815

perror_plus("ioctl SIOCGIFFLAGS");

1816

errno = old_errno;

1817

}

1818

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

1819

old_errno = errno;

1820

perror_plus("close");

1821

errno = old_errno;

1127

1822

}

1128

1823

return false;

1129

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1829

}

1130

1830

return true;

1131

1831

}

1132

1832

1833

__attribute__((nonnull, warn_unused_result))

1133

1834

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

1134

1835

1135

1836

/* Reject the loopback device */

1177

1878

* corresponds to an acceptable network device.

1178

1879

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

1179

1880

*/

1881

__attribute__((nonnull, warn_unused_result))

1180

1882

int good_interface(const struct dirent *if_entry){

1181

1883

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

1182

1884

return 0;

1198

1900

}

1199

1901

1200

1902

/*

1201

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

1202

* corresponds to an acceptable network device which is up.

1203

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

1204

*/

1205

int up_interface(const struct dirent *if_entry){

1206

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

1207

return 0;

1208

}

1209

1210

struct ifreq ifr;

1211

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

1212

if(debug){

1213

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

1214

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

1215

}

1216

return 0;

1217

}

1218

1219

/* Reject down interfaces */

1220

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

1221

if(debug){

1222

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

1223

if_entry->d_name);

1224

}

1225

return 0;

1226

}

1227

1228

/* Reject non-running interfaces */

1229

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

1230

if(debug){

1231

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

1232

if_entry->d_name);

1233

}

1234

return 0;

1235

}

1236

1237

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

1238

return 0;

1239

}

1240

return 1;

1241

}

1242

1903

* This function determines if a network interface is up.

1904

*/

1905

__attribute__((nonnull, warn_unused_result))

1906

bool interface_is_up(const char *interface){

1907

struct ifreq ifr;

1908

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

1909

if(debug){

1910

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

1911

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

1912

}

1913

return false;

1914

}

1915

1916

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

1917

}

1918

1919

/*

1920

* This function determines if a network interface is running

1921

*/

1922

__attribute__((nonnull, warn_unused_result))

1923

bool interface_is_running(const char *interface){

1924

struct ifreq ifr;

1925

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

1926

if(debug){

1927

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

1928

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

1929

}

1930

return false;

1931

}

1932

1933

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

1934

}

1935

1936

__attribute__((nonnull, pure, warn_unused_result))

1243

1937

int notdotentries(const struct dirent *direntry){

1244

1938

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

1245

1939

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

1252

1946

}

1253

1947

1254

1948

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

1949

__attribute__((nonnull, warn_unused_result))

1255

1950

int runnable_hook(const struct dirent *direntry){

1256

1951

int ret;

1257

1952

size_t sret;

1265

1960

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

1266

1961

"abcdefghijklmnopqrstuvwxyz"

1267

1962

"0123456789"

1268

"_-");

1963

"_.-");

1269

1964

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

1270

1965

/* Contains non-allowed characters */

1271

1966

if(debug){

1275

1970

return 0;

1276

1971

}

1277

1972

1278

char *fullname = NULL;

1279

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

1280

if(ret < 0){

1281

perror_plus("asprintf");

1282

return 0;

1283

}

1284

1285

ret = stat(fullname, &st);

1973

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

1286

1974

if(ret == -1){

1287

1975

if(debug){

1288

1976

perror_plus("Could not stat hook");

1312

2000

return 1;

1313

2001

}

1314

2002

1315

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2003

__attribute__((nonnull, warn_unused_result))

2004

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2005

mandos_context *mc){

1316

2006

int ret;

1317

2007

struct timespec now;

1318

2008

struct timespec waited_time;

1319

2009

intmax_t block_time;

1320

2010

1321

2011

while(true){

1322

if(mc.current_server == NULL){

1323

if (debug){

2012

if(mc->current_server == NULL){

2013

if(debug){

1324

2014

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

1325

2015

" No timeout!\n");

1326

2016

}

1327

2017

ret = avahi_simple_poll_iterate(s, -1);

1328

2018

} else {

1329

if (debug){

2019

if(debug){

1330

2020

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

1331

2021

" it, or wait\n");

1332

2022

}

1339

2029

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

1340

2030

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

1341

2031

waited_time.tv_sec = (now.tv_sec

1342

- mc.current_server->last_seen.tv_sec);

2032

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

1343

2033

waited_time.tv_nsec = (now.tv_nsec

1344

- mc.current_server->last_seen.tv_nsec);

2034

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

1345

2035

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

1346

2036

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

1347

2037

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

1349

2039

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

1350

2040

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

1351

2041

1352

if (debug){

2042

if(debug){

1353

2043

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

1354

2044

block_time);

1355

2045

}

1356

2046

1357

2047

if(block_time <= 0){

1358

ret = start_mandos_communication(mc.current_server->ip,

1359

mc.current_server->port,

1360

mc.current_server->if_index,

1361

mc.current_server->af);

2048

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

2049

mc->current_server->port,

2050

mc->current_server->if_index,

2051

mc->current_server->af, mc);

1362

2052

if(ret == 0){

1363

avahi_simple_poll_quit(mc.simple_poll);

2053

avahi_simple_poll_quit(s);

1364

2054

return 0;

1365

2055

}

1366

2056

ret = clock_gettime(CLOCK_MONOTONIC,

1367

&mc.current_server->last_seen);

2057

&mc->current_server->last_seen);

1368

2058

if(ret == -1){

1369

2059

perror_plus("clock_gettime");

1370

2060

return -1;

1371

2061

}

1372

mc.current_server = mc.current_server->next;

2062

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

1373

2063

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

1374

2064

servers, but don't block */

1375

2065

}

1377

2067

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

1378

2068

}

1379

2069

if(ret != 0){

1380

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

2070

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

1381

2071

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

1382

2072

}

1383

2073

}

1384

2074

}

1385

2075

}

1386

2076

1387

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

2077

__attribute__((nonnull))

2078

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

1388

2079

const float delay){

1389

struct dirent **direntries;

1390

struct dirent *direntry;

1391

int ret;

1392

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

1393

alphasort);

2080

struct dirent **direntries = NULL;

2081

if(hookdir_fd == -1){

2082

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2083

| O_CLOEXEC);

2084

if(hookdir_fd == -1){

2085

if(errno == ENOENT){

2086

if(debug){

2087

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

2088

" found\n", hookdir);

2089

}

2090

} else {

2091

perror_plus("open");

2092

}

2093

return;

2094

}

2095

}

2096

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

2097

if(devnull == -1){

2098

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

2099

return;

2100

}

2101

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

2102

runnable_hook, alphasort);

1394

2103

if(numhooks == -1){

1395

2104

perror_plus("scandir");

1396

} else {

1397

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

1398

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

1399

direntry = direntries[i];

1400

char *fullname = NULL;

1401

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

1402

if(ret < 0){

2105

close(devnull);

2106

return;

2107

}

2108

struct dirent *direntry;

2109

int ret;

2110

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

2111

direntry = direntries[i];

2112

if(debug){

2113

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

2114

direntry->d_name);

2115

}

2116

pid_t hook_pid = fork();

2117

if(hook_pid == 0){

2118

/* Child */

2119

/* Raise privileges */

2120

errno = raise_privileges_permanently();

2121

if(errno != 0){

2122

perror_plus("Failed to raise privileges");

2123

_exit(EX_NOPERM);

2124

}

2125

/* Set group */

2126

errno = 0;

2127

ret = setgid(0);

2128

if(ret == -1){

2129

perror_plus("setgid");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Reset supplementary groups */

2133

errno = 0;

2134

ret = setgroups(0, NULL);

2135

if(ret == -1){

2136

perror_plus("setgroups");

2137

_exit(EX_NOPERM);

2138

}

2139

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

2140

if(ret == -1){

2141

perror_plus("setenv");

2142

_exit(EX_OSERR);

2143

}

2144

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

2145

if(ret == -1){

2146

perror_plus("setenv");

2147

_exit(EX_OSERR);

2148

}

2149

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

2150

if(ret == -1){

2151

perror_plus("setenv");

2152

_exit(EX_OSERR);

2153

}

2154

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

2155

if(ret == -1){

2156

perror_plus("setenv");

2157

_exit(EX_OSERR);

2158

}

2159

char *delaystring;

2160

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

2161

if(ret == -1){

1403

2162

perror_plus("asprintf");

1404

continue;

1405

}

1406

if(debug){

1407

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

1408

direntry->d_name);

1409

}

1410

pid_t hook_pid = fork();

1411

if(hook_pid == 0){

1412

/* Child */

1413

/* Raise privileges */

1414

errno = 0;

1415

ret = seteuid(0);

1416

if(ret == -1){

1417

perror_plus("seteuid");

1418

}

1419

/* Raise privileges even more */

1420

errno = 0;

1421

ret = setuid(0);

1422

if(ret == -1){

1423

perror_plus("setuid");

1424

}

1425

/* Set group */

1426

errno = 0;

1427

ret = setgid(0);

1428

if(ret == -1){

1429

perror_plus("setgid");

1430

}

1431

/* Reset supplementary groups */

1432

errno = 0;

1433

ret = setgroups(0, NULL);

1434

if(ret == -1){

1435

perror_plus("setgroups");

1436

}

1437

dup2(devnull, STDIN_FILENO);

1438

close(devnull);

1439

dup2(STDERR_FILENO, STDOUT_FILENO);

1440

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

1441

if(ret == -1){

1442

perror_plus("setenv");

1443

_exit(EX_OSERR);

1444

}

1445

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

1446

if(ret == -1){

1447

perror_plus("setenv");

1448

_exit(EX_OSERR);

1449

}

1450

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

1451

if(ret == -1){

1452

perror_plus("setenv");

1453

_exit(EX_OSERR);

1454

}

1455

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

1456

if(ret == -1){

1457

perror_plus("setenv");

1458

_exit(EX_OSERR);

1459

}

1460

char *delaystring;

1461

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

1462

if(ret == -1){

1463

perror_plus("asprintf");

1464

_exit(EX_OSERR);

1465

}

1466

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

1467

if(ret == -1){

1468

free(delaystring);

1469

perror_plus("setenv");

1470

_exit(EX_OSERR);

1471

}

2163

_exit(EX_OSERR);

2164

}

2165

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

2166

if(ret == -1){

1472

2167

free(delaystring);

1473

ret = execl(fullname, direntry->d_name, mode, NULL);

1474

perror_plus("execl");

1475

} else {

1476

int status;

1477

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

1478

perror_plus("waitpid");

1479

free(fullname);

1480

continue;

1481

}

1482

if(WIFEXITED(status)){

1483

if(WEXITSTATUS(status) != 0){

1484

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

1485

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

1486

WEXITSTATUS(status));

1487

free(fullname);

1488

continue;

1489

}

1490

} else if(WIFSIGNALED(status)){

1491

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

1492

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

1493

WTERMSIG(status));

1494

free(fullname);

1495

continue;

1496

} else {

1497

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

1498

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

1499

free(fullname);

1500

continue;

1501

}

1502

}

1503

free(fullname);

1504

if(debug){

1505

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

1506

direntry->d_name);

1507

}

1508

}

1509

close(devnull);

1510

}

1511

return true;

2168

perror_plus("setenv");

2169

_exit(EX_OSERR);

2170

}

2171

free(delaystring);

2172

if(connect_to != NULL){

2173

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

2174

if(ret == -1){

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

}

2179

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

2180

direntry->d_name,

2181

O_RDONLY));

2182

if(hook_fd == -1){

2183

perror_plus("openat");

2184

_exit(EXIT_FAILURE);

2185

}

2186

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

2187

perror_plus("close");

2188

_exit(EXIT_FAILURE);

2189

}

2190

ret = dup2(devnull, STDIN_FILENO);

2191

if(ret == -1){

2192

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

2193

_exit(EX_OSERR);

2194

}

2195

ret = close(devnull);

2196

if(ret == -1){

2197

perror_plus("close");

2198

_exit(EX_OSERR);

2199

}

2200

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2201

if(ret == -1){

2202

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

2203

_exit(EX_OSERR);

2204

}

2205

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

2206

environ) == -1){

2207

perror_plus("fexecve");

2208

_exit(EXIT_FAILURE);

2209

}

2210

} else {

2211

if(hook_pid == -1){

2212

perror_plus("fork");

2213

free(direntry);

2214

continue;

2215

}

2216

int status;

2217

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

2218

perror_plus("waitpid");

2219

free(direntry);

2220

continue;

2221

}

2222

if(WIFEXITED(status)){

2223

if(WEXITSTATUS(status) != 0){

2224

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

2225

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

2226

WEXITSTATUS(status));

2227

free(direntry);

2228

continue;

2229

}

2230

} else if(WIFSIGNALED(status)){

2231

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

2232

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

2233

WTERMSIG(status));

2234

free(direntry);

2235

continue;

2236

} else {

2237

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

2238

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

2239

free(direntry);

2240

continue;

2241

}

2242

}

2243

if(debug){

2244

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

2245

direntry->d_name);

2246

}

2247

free(direntry);

2248

}

2249

free(direntries);

2250

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

2251

perror_plus("close");

2252

} else {

2253

hookdir_fd = -1;

2254

}

2255

close(devnull);

2256

}

2257

2258

__attribute__((nonnull, warn_unused_result))

2259

int bring_up_interface(const char *const interface,

2260

const float delay){

2261

int old_errno = errno;

2262

int ret;

2263

struct ifreq network;

2264

unsigned int if_index = if_nametoindex(interface);

2265

if(if_index == 0){

2266

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

2267

errno = old_errno;

2268

return ENXIO;

2269

}

2270

2271

if(quit_now){

2272

errno = old_errno;

2273

return EINTR;

2274

}

2275

2276

if(not interface_is_up(interface)){

2277

int ret_errno = 0;

2278

int ioctl_errno = 0;

2279

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

2280

ret_errno = errno;

2281

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

2282

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

2283

errno = old_errno;

2284

return ret_errno;

2285

}

2286

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

2287

2288

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

2289

if(sd == -1){

2290

ret_errno = errno;

2291

perror_plus("socket");

2292

errno = old_errno;

2293

return ret_errno;

2294

}

2295

2296

if(quit_now){

2297

ret = close(sd);

2298

if(ret == -1){

2299

perror_plus("close");

2300

}

2301

errno = old_errno;

2302

return EINTR;

2303

}

2304

2305

if(debug){

2306

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

2307

interface);

2308

}

2309

2310

/* Raise privileges */

2311

ret_errno = raise_privileges();

2312

if(ret_errno != 0){

2313

errno = ret_errno;

2314

perror_plus("Failed to raise privileges");

2315

}

2316

2317

#ifdef __linux__

2318

int ret_linux;

2319

bool restore_loglevel = false;

2320

if(ret_errno == 0){

2321

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2322

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

2323

ret_linux = klogctl(8, NULL, 5);

2324

if(ret_linux == -1){

2325

perror_plus("klogctl");

2326

} else {

2327

restore_loglevel = true;

2328

}

2329

}

2330

#endif /* __linux__ */

2331

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

2332

ioctl_errno = errno;

2333

#ifdef __linux__

2334

if(restore_loglevel){

2335

ret_linux = klogctl(7, NULL, 0);

2336

if(ret_linux == -1){

2337

perror_plus("klogctl");

2338

}

2339

}

2340

#endif /* __linux__ */

2341

2342

/* If raise_privileges() succeeded above */

2343

if(ret_errno == 0){

2344

/* Lower privileges */

2345

ret_errno = lower_privileges();

2346

if(ret_errno != 0){

2347

errno = ret_errno;

2348

perror_plus("Failed to lower privileges");

2349

}

2350

}

2351

2352

/* Close the socket */

2353

ret = close(sd);

2354

if(ret == -1){

2355

perror_plus("close");

2356

}

2357

2358

if(ret_setflags == -1){

2359

errno = ioctl_errno;

2360

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2361

errno = old_errno;

2362

return ioctl_errno;

2363

}

2364

} else if(debug){

2365

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

2366

interface);

2367

}

2368

2369

/* Sleep checking until interface is running.

2370

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

2371

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

2372

if(interface_is_running(interface)){

2373

break;

2374

}

2375

struct timespec sleeptime = { .tv_nsec = 250000000 };

2376

ret = nanosleep(&sleeptime, NULL);

2377

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

2378

perror_plus("nanosleep");

2379

}

2380

}

2381

2382

errno = old_errno;

2383

return 0;

2384

}

2385

2386

__attribute__((nonnull, warn_unused_result))

2387

int take_down_interface(const char *const interface){

2388

int old_errno = errno;

2389

struct ifreq network;

2390

unsigned int if_index = if_nametoindex(interface);

2391

if(if_index == 0){

2392

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

2393

errno = old_errno;

2394

return ENXIO;

2395

}

2396

if(interface_is_up(interface)){

2397

int ret_errno = 0;

2398

int ioctl_errno = 0;

2399

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

2400

ret_errno = errno;

2401

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

2402

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

2403

errno = old_errno;

2404

return ret_errno;

2405

}

2406

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

2407

2408

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

2409

if(sd == -1){

2410

ret_errno = errno;

2411

perror_plus("socket");

2412

errno = old_errno;

2413

return ret_errno;

2414

}

2415

2416

if(debug){

2417

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

2418

interface);

2419

}

2420

2421

/* Raise privileges */

2422

ret_errno = raise_privileges();

2423

if(ret_errno != 0){

2424

errno = ret_errno;

2425

perror_plus("Failed to raise privileges");

2426

}

2427

2428

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

2429

ioctl_errno = errno;

2430

2431

/* If raise_privileges() succeeded above */

2432

if(ret_errno == 0){

2433

/* Lower privileges */

2434

ret_errno = lower_privileges();

2435

if(ret_errno != 0){

2436

errno = ret_errno;

2437

perror_plus("Failed to lower privileges");

2438

}

2439

}

2440

2441

/* Close the socket */

2442

int ret = close(sd);

2443

if(ret == -1){

2444

perror_plus("close");

2445

}

2446

2447

if(ret_setflags == -1){

2448

errno = ioctl_errno;

2449

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2450

errno = old_errno;

2451

return ioctl_errno;

2452

}

2453

} else if(debug){

2454

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

2455

interface);

2456

}

2457

2458

errno = old_errno;

2459

return 0;

1512

2460

}

1513

2461

1514

2462

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

2463

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

2464

#if GNUTLS_VERSION_NUMBER >= 0x030606

2465

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

2466

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

2467

":%PROFILE_ULTRA",

2468

#elif GNUTLS_VERSION_NUMBER < 0x030600

2469

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

2470

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

2471

#else

2472

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

2473

#endif

2474

.current_server = NULL, .interfaces = NULL,

2475

.interfaces_size = 0 };

1515

2476

AvahiSServiceBrowser *sb = NULL;

1516

int error;

2477

error_t ret_errno;

1517

2478

int ret;

1518

2479

intmax_t tmpmax;

1519

2480

char *tmp;

1520

2481

int exitcode = EXIT_SUCCESS;

1521

const char *interface = "";

1522

struct ifreq network;

1523

int sd = -1;

1524

bool take_down_interface = false;

1525

uid_t uid;

1526

gid_t gid;

1527

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

1528

bool tempdir_created = false;

2482

char *interfaces_to_take_down = NULL;

2483

size_t interfaces_to_take_down_size = 0;

2484

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

2485

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

2486

char *tempdir = NULL;

1529

2487

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1530

2488

const char *seckey = PATHDIR "/" SECKEY;

1531

2489

const char *pubkey = PATHDIR "/" PUBKEY;

2490

#if GNUTLS_VERSION_NUMBER >= 0x030606

2491

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2492

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2493

#endif

2494

const char *dh_params_file = NULL;

2495

char *interfaces_hooks = NULL;

1532

2496

1533

2497

bool gnutls_initialized = false;

1534

2498

bool gpgme_initialized = false;

1580

2544

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

1581

2545

.arg = "FILE",

1582

2546

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

1583

.group = 2 },

2547

.group = 1 },

2548

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

2549

.arg = "FILE",

2550

#if GNUTLS_VERSION_NUMBER >= 0x030606

2551

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

2552

#else

2553

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

2554

#endif

2555

.group = 1 },

2556

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

2557

.arg = "FILE",

2558

#if GNUTLS_VERSION_NUMBER >= 0x030606

2559

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

2560

#else

2561

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

2562

#endif

2563

.group = 1 },

1584

2564

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

1585

2565

.arg = "BITS",

1586

2566

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

1587

2567

" Diffie-Hellman key exchange",

1588

2568

.group = 2 },

2569

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

2570

.arg = "FILE",

2571

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

2572

" for the Diffie-Hellman key exchange",

2573

.group = 2 },

1589

2574

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

1590

2575

.arg = "STRING",

1591

2576

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

1596

2581

.group = 2 },

1597

2582

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

1598

2583

.arg = "SECONDS",

1599

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

2584

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

1600

2585

.group = 2 },

1601

2586

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

1602

2587

.arg = "DIR",

1625

2610

connect_to = arg;

1626

2611

break;

1627

2612

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

1628

interface = arg;

2613

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

2614

arg, (int)',');

2615

if(ret_errno != 0){

2616

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

2617

}

1629

2618

break;

1630

2619

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

1631

2620

seckey = arg;

1633

2622

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

1634

2623

pubkey = arg;

1635

2624

break;

2625

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

2626

#if GNUTLS_VERSION_NUMBER >= 0x030606

2627

tls_privkey = arg;

2628

#endif

2629

break;

2630

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

2631

#if GNUTLS_VERSION_NUMBER >= 0x030606

2632

tls_pubkey = arg;

2633

#endif

2634

break;

1636

2635

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

1637

2636

errno = 0;

1638

2637

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

1642

2641

}

1643

2642

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

1644

2643

break;

2644

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

2645

dh_params_file = arg;

2646

break;

1645

2647

case 130: /* --priority */

1646

2648

mc.priority = arg;

1647

2649

break;

1687

2689

.args_doc = "",

1688

2690

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

1689

2691

" passwords from a Mandos server" };

1690

ret = argp_parse(&argp, argc, argv,

1691

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1692

switch(ret){

2692

ret_errno = argp_parse(&argp, argc, argv,

2693

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2694

switch(ret_errno){

1693

2695

case 0:

1694

2696

break;

1695

2697

case ENOMEM:

1696

2698

default:

1697

errno = ret;

2699

errno = ret_errno;

1698

2700

perror_plus("argp_parse");

1699

2701

exitcode = EX_OSERR;

1700

2702

goto end;

1703

2705

goto end;

1704

2706

}

1705

2707

}

1706

2708

1707

2709

{

1708

2710

/* Work around Debian bug #633582:

1709

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

2711

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

1710

2712

1711

/* Re-raise priviliges */

1712

errno = 0;

1713

ret = seteuid(0);

1714

if(ret == -1){

1715

perror_plus("seteuid");

2713

/* Re-raise privileges */

2714

ret = raise_privileges();

2715

if(ret != 0){

2716

errno = ret;

2717

perror_plus("Failed to raise privileges");

1716

2718

} else {

1717

2719

struct stat st;

1718

2720

1733

2735

}

1734

2736

}

1735

2737

}

1736

TEMP_FAILURE_RETRY(close(seckey_fd));

2738

close(seckey_fd);

1737

2739

}

1738

2740

}

1739

2741

1740

2742

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

1741

2743

int pubkey_fd = open(pubkey, O_RDONLY);

1742

2744

if(pubkey_fd == -1){

1754

2756

}

1755

2757

}

1756

2758

}

1757

TEMP_FAILURE_RETRY(close(pubkey_fd));

1758

}

1759

}

1760

2759

close(pubkey_fd);

2760

}

2761

}

2762

2763

if(dh_params_file != NULL

2764

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

2765

int dhparams_fd = open(dh_params_file, O_RDONLY);

2766

if(dhparams_fd == -1){

2767

perror_plus("open");

2768

} else {

2769

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

2770

if(ret == -1){

2771

perror_plus("fstat");

2772

} else {

2773

if(S_ISREG(st.st_mode)

2774

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

2775

ret = fchown(dhparams_fd, uid, gid);

2776

if(ret == -1){

2777

perror_plus("fchown");

2778

}

2779

}

2780

}

2781

close(dhparams_fd);

2782

}

2783

}

2784

1761

2785

/* Lower privileges */

1762

errno = 0;

1763

ret = seteuid(uid);

1764

if(ret == -1){

1765

perror_plus("seteuid");

2786

ret = lower_privileges();

2787

if(ret != 0){

2788

errno = ret;

2789

perror_plus("Failed to lower privileges");

2790

}

2791

}

2792

}

2793

2794

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

2795

{

2796

char *interface = NULL;

2797

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

2798

interface))){

2799

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

2800

and if_nametoindex(interface) == 0){

2801

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

2802

fprintf_plus(stderr, "Not using nonexisting interface"

2803

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

2804

}

2805

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

2806

interface = NULL;

1766

2807

}

1767

2808

}

1768

2809

}

1769

2810

1770

2811

/* Run network hooks */

1771

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

1772

goto end;

2812

{

2813

if(mc.interfaces != NULL){

2814

interfaces_hooks = malloc(mc.interfaces_size);

2815

if(interfaces_hooks == NULL){

2816

perror_plus("malloc");

2817

goto end;

2818

}

2819

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

2820

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

2821

}

2822

run_network_hooks("start", interfaces_hooks != NULL ?

2823

interfaces_hooks : "", delay);

1773

2824

}

1774

2825

1775

2826

if(not debug){

1776

2827

avahi_set_log_function(empty_log);

1777

2828

}

1778

2829

1779

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

1780

struct dirent **direntries;

1781

/* First look for interfaces that are up */

1782

ret = scandir(sys_class_net, &direntries, up_interface,

1783

alphasort);

1784

if(ret == 0){

1785

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

1786

free(direntries);

1787

ret = scandir(sys_class_net, &direntries, good_interface,

1788

alphasort);

1789

}

1790

if(ret >= 1){

1791

/* Pick the first interface returned */

1792

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

1793

if(debug){

1794

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

1795

}

1796

if(interface == NULL){

1797

perror_plus("malloc");

1798

free(direntries);

1799

exitcode = EXIT_FAILURE;

1800

goto end;

1801

}

1802

free(direntries);

1803

} else {

1804

free(direntries);

1805

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

1806

exitcode = EXIT_FAILURE;

1807

goto end;

1808

}

1809

}

1810

1811

2830

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

1812

2831

from the signal handler */

1813

2832

/* Initialize the pseudo-RNG for Avahi */

1814

2833

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

1815

mc.simple_poll = avahi_simple_poll_new();

1816

if(mc.simple_poll == NULL){

2834

simple_poll = avahi_simple_poll_new();

2835

if(simple_poll == NULL){

1817

2836

fprintf_plus(stderr,

1818

2837

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

1819

2838

exitcode = EX_UNAVAILABLE;

1883

2902

}

1884

2903

}

1885

2904

1886

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

1887

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

1888

if_index = (AvahiIfIndex) if_nametoindex(interface);

1889

if(if_index == 0){

1890

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

1891

exitcode = EX_UNAVAILABLE;

1892

goto end;

1893

}

1894

1895

if(quit_now){

1896

goto end;

1897

}

1898

1899

/* Re-raise priviliges */

1900

errno = 0;

1901

ret = seteuid(0);

1902

if(ret == -1){

1903

perror_plus("seteuid");

1904

}

1905

1906

#ifdef __linux__

1907

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1908

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

1909

ret = klogctl(8, NULL, 5);

1910

bool restore_loglevel = true;

1911

if(ret == -1){

1912

restore_loglevel = false;

1913

perror_plus("klogctl");

1914

}

1915

#endif /* __linux__ */

1916

1917

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1918

if(sd < 0){

1919

perror_plus("socket");

1920

exitcode = EX_OSERR;

1921

#ifdef __linux__

1922

if(restore_loglevel){

1923

ret = klogctl(7, NULL, 0);

1924

if(ret == -1){

1925

perror_plus("klogctl");

1926

}

1927

}

1928

#endif /* __linux__ */

1929

/* Lower privileges */

1930

errno = 0;

1931

ret = seteuid(uid);

1932

if(ret == -1){

1933

perror_plus("seteuid");

1934

}

1935

goto end;

1936

}

1937

strcpy(network.ifr_name, interface);

1938

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

1939

if(ret == -1){

1940

perror_plus("ioctl SIOCGIFFLAGS");

1941

#ifdef __linux__

1942

if(restore_loglevel){

1943

ret = klogctl(7, NULL, 0);

1944

if(ret == -1){

1945

perror_plus("klogctl");

1946

}

1947

}

1948

#endif /* __linux__ */

1949

exitcode = EX_OSERR;

1950

/* Lower privileges */

1951

errno = 0;

1952

ret = seteuid(uid);

1953

if(ret == -1){

1954

perror_plus("seteuid");

1955

}

1956

goto end;

1957

}

1958

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

1959

network.ifr_flags |= IFF_UP;

1960

take_down_interface = true;

1961

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

1962

if(ret == -1){

1963

take_down_interface = false;

1964

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1965

exitcode = EX_OSERR;

1966

#ifdef __linux__

1967

if(restore_loglevel){

1968

ret = klogctl(7, NULL, 0);

1969

if(ret == -1){

1970

perror_plus("klogctl");

2905

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

2906

if(mc.interfaces == NULL){

2907

struct dirent **direntries = NULL;

2908

/* Look for any good interfaces */

2909

ret = scandir(sys_class_net, &direntries, good_interface,

2910

alphasort);

2911

if(ret >= 1){

2912

/* Add all found interfaces to interfaces list */

2913

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

2914

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

2915

direntries[i]->d_name);

2916

if(ret_errno != 0){

2917

errno = ret_errno;

2918

perror_plus("argz_add");

2919

free(direntries[i]);

2920

continue;

2921

}

2922

if(debug){

2923

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

2924

direntries[i]->d_name);

2925

}

2926

free(direntries[i]);

2927

}

2928

free(direntries);

2929

} else {

2930

if(ret == 0){

2931

free(direntries);

2932

}

2933

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

2934

exitcode = EXIT_FAILURE;

2935

goto end;

2936

}

2937

}

2938

2939

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

2940

{

2941

char *interface = NULL;

2942

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

2943

interface))){

2944

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

2945

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

2946

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

2947

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

2948

interface);

2949

interface = NULL;

2950

while((interface = argz_next(mc.interfaces,

2951

mc.interfaces_size, interface))){

2952

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

2953

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

2954

interface);

2955

interface = NULL;

1971

2956

}

1972

2957

}

1973

#endif /* __linux__ */

1974

/* Lower privileges */

1975

errno = 0;

1976

ret = seteuid(uid);

1977

if(ret == -1){

1978

perror_plus("seteuid");

1979

}

1980

goto end;

1981

}

1982

}

1983

/* Sleep checking until interface is running.

1984

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

1985

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

1986

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

1987

if(ret == -1){

1988

perror_plus("ioctl SIOCGIFFLAGS");

1989

} else if(network.ifr_flags & IFF_RUNNING){

1990

2958

break;

1991

2959

}

1992

struct timespec sleeptime = { .tv_nsec = 250000000 };

1993

ret = nanosleep(&sleeptime, NULL);

1994

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

1995

perror_plus("nanosleep");

1996

}

1997

}

1998

if(not take_down_interface){

1999

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

2000

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

2001

if(ret == -1){

2002

perror_plus("close");

2003

}

2004

}

2005

#ifdef __linux__

2006

if(restore_loglevel){

2007

/* Restores kernel loglevel to default */

2008

ret = klogctl(7, NULL, 0);

2009

if(ret == -1){

2010

perror_plus("klogctl");

2011

}

2012

}

2013

#endif /* __linux__ */

2014

/* Lower privileges */

2015

errno = 0;

2016

/* Lower privileges */

2017

ret = seteuid(uid);

2018

if(ret == -1){

2019

perror_plus("seteuid");

2020

}

2960

bool interface_was_up = interface_is_up(interface);

2961

errno = bring_up_interface(interface, delay);

2962

if(not interface_was_up){

2963

if(errno != 0){

2964

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

2965

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

2966

} else {

2967

errno = argz_add(&interfaces_to_take_down,

2968

&interfaces_to_take_down_size,

2969

interface);

2970

if(errno != 0){

2971

perror_plus("argz_add");

2972

}

2973

}

2974

}

2975

}

2976

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

2977

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

2978

}

2979

}

2980

2981

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

2982

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

2983

if(debug){

2984

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

2985

mc.interfaces);

2986

}

2987

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

2021

2988

}

2022

2989

2023

2990

if(quit_now){

2024

2991

goto end;

2025

2992

}

2026

2993

2027

ret = init_gnutls_global(pubkey, seckey);

2994

#if GNUTLS_VERSION_NUMBER >= 0x030606

2995

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

2996

#elif GNUTLS_VERSION_NUMBER < 0x030600

2997

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

2998

#else

2999

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

3000

#endif

2028

3001

if(ret == -1){

2029

3002

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

2030

3003

exitcode = EX_UNAVAILABLE;

2037

3010

goto end;

2038

3011

}

2039

3012

2040

if(mkdtemp(tempdir) == NULL){

3013

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

3014

tempdir = mkdtemp(run_tempdir);

3015

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

3016

if(debug){

3017

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

3018

run_tempdir, old_tempdir);

3019

}

3020

tempdir = mkdtemp(old_tempdir);

3021

}

3022

if(tempdir == NULL){

2041

3023

perror_plus("mkdtemp");

2042

3024

goto end;

2043

3025

}

2044

tempdir_created = true;

2045

3026

2046

3027

if(quit_now){

2047

3028

goto end;

2048

3029

}

2049

3030

2050

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

3031

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

2051

3032

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

2052

3033

exitcode = EX_UNAVAILABLE;

2053

3034

goto end;

2063

3044

/* Connect directly, do not use Zeroconf */

2064

3045

/* (Mainly meant for debugging) */

2065

3046

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

3047

2066

3048

if(address == NULL){

2067

3049

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

2068

3050

exitcode = EX_USAGE;

2073

3055

goto end;

2074

3056

}

2075

3057

2076

uint16_t port;

3058

in_port_t port;

2077

3059

errno = 0;

2078

3060

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

2079

3061

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

2080

or tmpmax != (uint16_t)tmpmax){

3062

or tmpmax != (in_port_t)tmpmax){

2081

3063

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

2082

3064

exitcode = EX_USAGE;

2083

3065

goto end;

2084

3066

}

2085

3067

2086

3068

if(quit_now){

2087

3069

goto end;

2088

3070

}

2089

3071

2090

port = (uint16_t)tmpmax;

3072

port = (in_port_t)tmpmax;

2091

3073

*address = '\0';

2092

3074

/* Colon in address indicates IPv6 */

2093

3075

int af;

2109

3091

}

2110

3092

2111

3093

while(not quit_now){

2112

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

3094

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

3095

&mc);

2113

3096

if(quit_now or ret == 0){

2114

3097

break;

2115

3098

}

2117

3100

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

2118

3101

(int)retry_interval);

2119

3102

}

2120

sleep((int)retry_interval);

3103

sleep((unsigned int)retry_interval);

2121

3104

}

2122

3105

2123

if (not quit_now){

3106

if(not quit_now){

2124

3107

exitcode = EXIT_SUCCESS;

2125

3108

}

2126

3109

2141

3124

config.publish_domain = 0;

2142

3125

2143

3126

/* Allocate a new server */

2144

mc.server = avahi_server_new(avahi_simple_poll_get

2145

(mc.simple_poll), &config, NULL,

2146

NULL, &error);

3127

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3128

&config, NULL, NULL, &ret);

2147

3129

2148

3130

/* Free the Avahi configuration data */

2149

3131

avahi_server_config_free(&config);

2152

3134

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

2153

3135

if(mc.server == NULL){

2154

3136

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

2155

avahi_strerror(error));

3137

avahi_strerror(ret));

2156

3138

exitcode = EX_UNAVAILABLE;

2157

3139

goto end;

2158

3140

}

2164

3146

/* Create the Avahi service browser */

2165

3147

sb = avahi_s_service_browser_new(mc.server, if_index,

2166

3148

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2167

NULL, 0, browse_callback, NULL);

3149

NULL, 0, browse_callback,

3150

(void *)&mc);

2168

3151

if(sb == NULL){

2169

3152

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

2170

3153

avahi_strerror(avahi_server_errno(mc.server)));

2181

3164

if(debug){

2182

3165

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

2183

3166

}

2184

2185

ret = avahi_loop_with_timeout(mc.simple_poll,

2186

(int)(retry_interval * 1000));

3167

3168

ret = avahi_loop_with_timeout(simple_poll,

3169

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

2187

3170

if(debug){

2188

3171

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

2189

3172

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

2192

3175

end:

2193

3176

2194

3177

if(debug){

2195

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

3178

if(signal_received){

3179

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

3180

argv[0], signal_received,

3181

strsignal(signal_received));

3182

} else {

3183

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

3184

}

2196

3185

}

2197

3186

2198

3187

/* Cleanup things */

3188

free(mc.interfaces);

3189

2199

3190

if(sb != NULL)

2200

3191

avahi_s_service_browser_free(sb);

2201

3192

2202

3193

if(mc.server != NULL)

2203

3194

avahi_server_free(mc.server);

2204

3195

2205

if(mc.simple_poll != NULL)

2206

avahi_simple_poll_free(mc.simple_poll);

3196

if(simple_poll != NULL)

3197

avahi_simple_poll_free(simple_poll);

2207

3198

2208

3199

if(gnutls_initialized){

2209

3200

gnutls_certificate_free_credentials(mc.cred);

2210

gnutls_global_deinit();

2211

3201

gnutls_dh_params_deinit(mc.dh_params);

2212

3202

}

2213

3203

2221

3211

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

2222

3212

while(mc.current_server != NULL){

2223

3213

server *next = mc.current_server->next;

3214

#ifdef __GNUC__

3215

#pragma GCC diagnostic push

3216

#pragma GCC diagnostic ignored "-Wcast-qual"

3217

#endif

3218

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

3219

#ifdef __GNUC__

3220

#pragma GCC diagnostic pop

3221

#endif

2224

3222

free(mc.current_server);

2225

3223

mc.current_server = next;

2226

3224

}

2227

3225

}

2228

3226

2229

/* Run network hooks */

2230

run_network_hooks("stop", interface, delay);

2231

2232

/* Re-raise priviliges */

3227

/* Re-raise privileges */

2233

3228

{

2234

errno = 0;

2235

ret = seteuid(0);

2236

if(ret == -1){

2237

perror_plus("seteuid");

3229

ret = raise_privileges();

3230

if(ret != 0){

3231

errno = ret;

3232

perror_plus("Failed to raise privileges");

3233

} else {

3234

3235

/* Run network hooks */

3236

run_network_hooks("stop", interfaces_hooks != NULL ?

3237

interfaces_hooks : "", delay);

3238

3239

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

3240

{

3241

char *interface = NULL;

3242

while((interface = argz_next(interfaces_to_take_down,

3243

interfaces_to_take_down_size,

3244

interface))){

3245

ret = take_down_interface(interface);

3246

if(ret != 0){

3247

errno = ret;

3248

perror_plus("Failed to take down interface");

3249

}

3250

}

3251

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

3252

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

3253

" down\n");

3254

}

3255

}

2238

3256

}

2239

3257

2240

/* Take down the network interface */

2241

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

2242

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

2243

if(ret == -1){

2244

perror_plus("ioctl SIOCGIFFLAGS");

2245

} else if(network.ifr_flags & IFF_UP){

2246

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

2247

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

2248

if(ret == -1){

2249

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2250

}

2251

}

2252

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

2253

if(ret == -1){

2254

perror_plus("close");

2255

}

3258

ret = lower_privileges_permanently();

3259

if(ret != 0){

3260

errno = ret;

3261

perror_plus("Failed to lower privileges permanently");

2256

3262

}

2257

3263

}

2258

/* Lower privileges permanently */

2259

errno = 0;

2260

ret = setuid(uid);

2261

if(ret == -1){

2262

perror_plus("setuid");

3264

3265

free(interfaces_to_take_down);

3266

free(interfaces_hooks);

3267

3268

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

3269

uintmax_t level){

3270

struct dirent **direntries = NULL;

3271

int dret;

3272

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

3273

O_RDONLY

3274

| O_NOFOLLOW

3275

| O_DIRECTORY

3276

| O_PATH));

3277

if(dir_fd == -1){

3278

perror_plus("open");

3279

return;

3280

}

3281

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

3282

notdotentries, alphasort);

3283

if(numentries >= 0){

3284

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

3285

if(debug){

3286

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

3287

dirname, direntries[i]->d_name);

3288

}

3289

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

3290

if(dret == -1){

3291

if(errno == EISDIR){

3292

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

3293

AT_REMOVEDIR);

3294

}

3295

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

3296

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

3297

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

3298

/* Recurse only in this special case */

3299

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

3300

dret = 0;

3301

}

3302

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

3303

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

3304

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

3305

}

3306

}

3307

free(direntries[i]);

3308

}

3309

3310

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

3311

free(direntries);

3312

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3313

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

3314

perror_plus("rmdir");

3315

}

3316

} else {

3317

perror_plus("scandirat");

3318

}

3319

close(dir_fd);

2263

3320

}

2264

3321

2265

3322

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

2266

if(tempdir_created){

2267

struct dirent **direntries = NULL;

2268

struct dirent *direntry = NULL;

2269

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

2270

alphasort);

2271

if (numentries > 0){

2272

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

2273

direntry = direntries[i];

2274

char *fullname = NULL;

2275

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

2276

direntry->d_name);

2277

if(ret < 0){

2278

perror_plus("asprintf");

2279

continue;

2280

}

2281

ret = remove(fullname);

2282

if(ret == -1){

2283

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

2284

strerror(errno));

2285

}

2286

free(fullname);

2287

}

2288

}

2289

2290

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

2291

free(direntries);

2292

if (numentries == -1){

2293

perror_plus("scandir");

2294

}

2295

ret = rmdir(tempdir);

2296

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

2297

perror_plus("rmdir");

2298

}

3323

if(tempdir != NULL){

3324

clean_dir_at(-1, tempdir, 0);

2299

3325

}

2300

3326

2301

3327

if(quit_now){