/mandos/release : revision 237.7.515

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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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SOCK_STREAM, uid_t, gid_t, open(),

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opendir(), DIR */

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

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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strtoimax() */

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

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

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#include <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() */

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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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raise() */

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

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EX_NOHOST, EX_IOERR, EX_PROTOCOL */

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

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WEXITSTATUS(), WTERMSIG() */

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

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

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argz_delete(), argz_append(),

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argz_stringify(), argz_add(),

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argz_count() */

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

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EAI_SYSTEM, gai_strerror() */

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#ifdef __linux__

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

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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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/* 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 mandos_protocol_version[] = "1";

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

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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

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}

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/*

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

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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}

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

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int add_server(const char *ip, uint16_t port,

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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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perror_plus("malloc");

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return -1;

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return false;

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}

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

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.port = port,

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.if_index = if_index,

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.af = af };

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.port = port,

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.if_index = if_index,

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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return -1;

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free(new_server);

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return false;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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if (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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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return -1;

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}

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return 0;

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(*current_server)->prev = new_server;

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}

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return true;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges(void){

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int old_errno = errno;

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int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

297

int raise_privileges_permanently(void){

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int old_errno = errno;

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int ret = raise_privileges();

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if(ret != 0){

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errno = old_errno;

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return ret;

303

}

304

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

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ret = errno;

306

}

307

errno = old_errno;

308

return ret;

309

}

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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){

314

int old_errno = errno;

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int ret = 0;

316

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))

325

int lower_privileges_permanently(void){

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int old_errno = errno;

327

int ret = 0;

328

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

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ret = errno;

330

}

331

errno = old_errno;

332

return ret;

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}

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/*

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* Initialize GPGME.

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337

*/

231

static bool init_gpgme(const char *seckey,

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const char *pubkey, const char *tempdir){

338

__attribute__((nonnull, warn_unused_result))

339

static bool init_gpgme(const char * const seckey,

340

const char * const pubkey,

341

const char * const tempdir,

342

mandos_context *mc){

233

343

gpgme_error_t rc;

234

344

gpgme_engine_info_t engine_info;

235

345

236

237

346

/*

238

347

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

239

348

*/

240

bool import_key(const char *filename){

349

bool import_key(const char * const filename){

241

350

int ret;

242

351

int fd;

243

352

gpgme_data_t pgp_data;

248

357

return false;

249

358

}

250

359

360

/* 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

251

410

rc = gpgme_data_new_from_fd(&pgp_data, fd);

252

411

if(rc != GPG_ERR_NO_ERROR){

253

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

254

gpgme_strsource(rc), gpgme_strerror(rc));

412

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

413

gpgme_strsource(rc), gpgme_strerror(rc));

255

414

return false;

256

415

}

257

416

258

rc = gpgme_op_import(mc.ctx, pgp_data);

417

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

259

418

if(rc != GPG_ERR_NO_ERROR){

260

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

261

gpgme_strsource(rc), gpgme_strerror(rc));

419

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

420

gpgme_strsource(rc), gpgme_strerror(rc));

262

421

return false;

263

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

}

264

498

265

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

499

ret = close(fd);

266

500

if(ret == -1){

267

501

perror_plus("close");

268

502

}

271

505

}

272

506

273

507

if(debug){

274

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

508

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

275

509

}

276

510

277

511

/* Init GPGME */

278

512

gpgme_check_version(NULL);

279

513

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

280

514

if(rc != GPG_ERR_NO_ERROR){

281

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

282

gpgme_strsource(rc), gpgme_strerror(rc));

515

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

516

gpgme_strsource(rc), gpgme_strerror(rc));

283

517

return false;

284

518

}

285

519

286

520

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

287

521

rc = gpgme_get_engine_info(&engine_info);

288

522

if(rc != GPG_ERR_NO_ERROR){

289

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

290

gpgme_strsource(rc), gpgme_strerror(rc));

523

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

524

gpgme_strsource(rc), gpgme_strerror(rc));

291

525

return false;

292

526

}

293

527

while(engine_info != NULL){

299

533

engine_info = engine_info->next;

300

534

}

301

535

if(engine_info == NULL){

302

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

536

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

537

tempdir);

303

538

return false;

304

539

}

305

540

306

541

/* Create new GPGME "context" */

307

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

542

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

308

543

if(rc != GPG_ERR_NO_ERROR){

309

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

310

gpgme_strsource(rc), gpgme_strerror(rc));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

311

546

return false;

312

547

}

313

548

322

557

* Decrypt OpenPGP data.

323

558

* Returns -1 on error

324

559

*/

560

__attribute__((nonnull, warn_unused_result))

325

561

static ssize_t pgp_packet_decrypt(const char *cryptotext,

326

562

size_t crypto_size,

327

char **plaintext){

563

char **plaintext,

564

mandos_context *mc){

328

565

gpgme_data_t dh_crypto, dh_plain;

329

566

gpgme_error_t rc;

330

567

ssize_t ret;

332

569

ssize_t plaintext_length = 0;

333

570

334

571

if(debug){

335

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

572

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

336

573

}

337

574

338

575

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

339

576

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

340

577

0);

341

578

if(rc != GPG_ERR_NO_ERROR){

342

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

343

gpgme_strsource(rc), gpgme_strerror(rc));

579

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

580

gpgme_strsource(rc), gpgme_strerror(rc));

344

581

return -1;

345

582

}

346

583

347

584

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

348

585

rc = gpgme_data_new(&dh_plain);

349

586

if(rc != GPG_ERR_NO_ERROR){

350

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

351

gpgme_strsource(rc), gpgme_strerror(rc));

587

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

588

gpgme_strsource(rc), gpgme_strerror(rc));

352

589

gpgme_data_release(dh_crypto);

353

590

return -1;

354

591

}

355

592

356

593

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

357

594

data buffer */

358

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

595

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

359

596

if(rc != GPG_ERR_NO_ERROR){

360

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

361

gpgme_strsource(rc), gpgme_strerror(rc));

597

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

598

gpgme_strsource(rc), gpgme_strerror(rc));

362

599

plaintext_length = -1;

363

600

if(debug){

364

601

gpgme_decrypt_result_t result;

365

result = gpgme_op_decrypt_result(mc.ctx);

602

result = gpgme_op_decrypt_result(mc->ctx);

366

603

if(result == NULL){

367

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

604

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

368

605

} else {

369

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

370

result->unsupported_algorithm);

371

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

372

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");

373

612

if(result->file_name != NULL){

374

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

613

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

375

614

}

376

gpgme_recipient_t recipient;

377

recipient = result->recipients;

378

while(recipient != NULL){

379

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

380

gpgme_pubkey_algo_name(recipient->pubkey_algo));

381

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

382

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

383

recipient->status == GPG_ERR_NO_SECKEY

384

? "No" : "Yes");

385

recipient = recipient->next;

615

616

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

617

r = r->next){

618

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

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

621

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

622

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

386

623

}

387

624

}

388

625

}

390

627

}

391

628

392

629

if(debug){

393

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

630

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

394

631

}

395

632

396

633

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

403

640

*plaintext = NULL;

404

641

while(true){

405

642

plaintext_capacity = incbuffer(plaintext,

406

(size_t)plaintext_length,

407

plaintext_capacity);

643

(size_t)plaintext_length,

644

plaintext_capacity);

408

645

if(plaintext_capacity == 0){

409

perror_plus("incbuffer");

410

plaintext_length = -1;

411

goto decrypt_end;

646

perror_plus("incbuffer");

647

plaintext_length = -1;

648

goto decrypt_end;

412

649

}

413

650

414

651

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

427

664

}

428

665

429

666

if(debug){

430

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

667

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

431

668

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

432

669

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

433

670

}

444

681

return plaintext_length;

445

682

}

446

683

447

static const char * safer_gnutls_strerror(int value){

448

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

449

-Wunreachable-code */

450

if(ret == NULL)

451

ret = "(unknown)";

452

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);

453

695

}

454

696

455

697

/* GnuTLS log function callback */

698

__attribute__((nonnull))

456

699

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

457

700

const char* string){

458

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

701

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

459

702

}

460

703

704

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

461

705

static int init_gnutls_global(const char *pubkeyfilename,

462

const char *seckeyfilename){

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

mandos_context *mc){

463

709

int ret;

464

710

465

711

if(debug){

466

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

467

}

468

469

ret = gnutls_global_init();

470

if(ret != GNUTLS_E_SUCCESS){

471

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

472

safer_gnutls_strerror(ret));

473

return -1;

712

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

474

713

}

475

714

476

715

if(debug){

482

721

}

483

722

484

723

/* OpenPGP credentials */

485

ret = gnutls_certificate_allocate_credentials(&mc.cred);

724

ret = gnutls_certificate_allocate_credentials(&mc->cred);

486

725

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

489

gnutls_global_deinit();

726

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

727

safer_gnutls_strerror(ret));

490

728

return -1;

491

729

}

492

730

493

731

if(debug){

494

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

495

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

496

seckeyfilename);

732

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

733

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

734

pubkeyfilename,

735

seckeyfilename);

497

736

}

498

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

499

751

ret = gnutls_certificate_set_openpgp_key_file

500

(mc.cred, pubkeyfilename, seckeyfilename,

752

(mc->cred, pubkeyfilename, seckeyfilename,

501

753

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

502

757

if(ret != GNUTLS_E_SUCCESS){

503

fprintf(stderr,

504

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

505

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

506

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

507

safer_gnutls_strerror(ret));

758

fprintf_plus(stderr,

759

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

760

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

761

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

762

safer_gnutls_strerror(ret));

508

763

goto globalfail;

509

764

}

510

765

511

766

/* GnuTLS server initialization */

512

ret = gnutls_dh_params_init(&mc.dh_params);

513

if(ret != GNUTLS_E_SUCCESS){

514

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

515

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

516

goto globalfail;

517

}

518

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

519

if(ret != GNUTLS_E_SUCCESS){

520

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

521

safer_gnutls_strerror(ret));

522

goto globalfail;

523

}

524

525

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

767

ret = gnutls_dh_params_init(&mc->dh_params);

768

if(ret != GNUTLS_E_SUCCESS){

769

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

770

" initialization: %s\n",

771

safer_gnutls_strerror(ret));

772

goto globalfail;

773

}

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

}

526

956

527

957

return 0;

528

958

529

959

globalfail:

530

960

531

gnutls_certificate_free_credentials(mc.cred);

532

gnutls_global_deinit();

533

gnutls_dh_params_deinit(mc.dh_params);

961

gnutls_certificate_free_credentials(mc->cred);

962

gnutls_dh_params_deinit(mc->dh_params);

534

963

return -1;

535

964

}

536

965

537

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){

538

969

int ret;

539

970

/* GnuTLS session creation */

540

971

do {

541

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

));

542

980

if(quit_now){

543

981

return -1;

544

982

}

545

983

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

546

984

if(ret != GNUTLS_E_SUCCESS){

547

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

548

safer_gnutls_strerror(ret));

985

fprintf_plus(stderr,

986

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

987

safer_gnutls_strerror(ret));

549

988

}

550

989

551

990

{

552

991

const char *err;

553

992

do {

554

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

993

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

555

994

if(quit_now){

556

995

gnutls_deinit(*session);

557

996

return -1;

558

997

}

559

998

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

560

999

if(ret != GNUTLS_E_SUCCESS){

561

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

562

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

563

safer_gnutls_strerror(ret));

1000

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

1001

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

1002

safer_gnutls_strerror(ret));

564

1003

gnutls_deinit(*session);

565

1004

return -1;

566

1005

}

568

1007

569

1008

do {

570

1009

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

571

mc.cred);

1010

mc->cred);

572

1011

if(quit_now){

573

1012

gnutls_deinit(*session);

574

1013

return -1;

575

1014

}

576

1015

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

577

1016

if(ret != GNUTLS_E_SUCCESS){

578

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

579

safer_gnutls_strerror(ret));

1017

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

1018

safer_gnutls_strerror(ret));

580

1019

gnutls_deinit(*session);

581

1020

return -1;

582

1021

}

584

1023

/* ignore client certificate if any. */

585

1024

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

586

1025

587

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

588

589

1026

return 0;

590

1027

}

591

1028

593

1030

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

594

1031

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

595

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

596

1199

/* Called when a Mandos server is found */

597

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,

598

1202

AvahiIfIndex if_index,

599

int af){

1203

int af, mandos_context *mc){

600

1204

int ret, tcp_sd = -1;

601

1205

ssize_t sret;

602

union {

603

struct sockaddr_in in;

604

struct sockaddr_in6 in6;

605

} to;

1206

struct sockaddr_storage to;

606

1207

char *buffer = NULL;

607

1208

char *decrypted_buffer = NULL;

608

1209

size_t buffer_length = 0;

611

1212

int retval = -1;

612

1213

gnutls_session_t session;

613

1214

int pf; /* Protocol family */

1215

bool route_added = false;

614

1216

615

1217

errno = 0;

616

1218

627

1229

pf = PF_INET;

628

1230

break;

629

1231

default:

630

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

1232

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

631

1233

errno = EINVAL;

632

1234

return -1;

633

1235

}

634

1236

635

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);

636

1271

if(ret != 0){

637

1272

return -1;

638

1273

}

639

1274

640

1275

if(debug){

641

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

642

"\n", ip, port);

1276

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

1277

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

643

1278

}

644

1279

645

tcp_sd = socket(pf, SOCK_STREAM, 0);

1280

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

646

1281

if(tcp_sd < 0){

647

1282

int e = errno;

648

1283

perror_plus("socket");

655

1290

goto mandos_end;

656

1291

}

657

1292

658

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

659

1293

if(af == AF_INET6){

660

to.in6.sin6_family = (sa_family_t)af;

661

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);

662

1297

} else { /* IPv4 */

663

to.in.sin_family = (sa_family_t)af;

664

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);

665

1301

}

666

1302

if(ret < 0 ){

667

1303

int e = errno;

671

1307

}

672

1308

if(ret == 0){

673

1309

int e = errno;

674

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

1310

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

675

1311

errno = e;

676

1312

goto mandos_end;

677

1313

}

678

1314

if(af == AF_INET6){

679

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

680

-Wconversion and

681

-Wunreachable-code */

682

683

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

684

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

685

-Wunreachable-code*/

1315

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

1316

if(IN6_IS_ADDR_LINKLOCAL

1317

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

686

1318

if(if_index == AVAHI_IF_UNSPEC){

687

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

688

" without a network interface\n");

1319

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

1320

" incomplete without a network interface\n");

689

1321

errno = EINVAL;

690

1322

goto mandos_end;

691

1323

}

692

1324

/* Set the network interface number as scope */

693

to.in6.sin6_scope_id = (uint32_t)if_index;

1325

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

694

1326

}

695

1327

} else {

696

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

697

-Wconversion and

698

-Wunreachable-code */

1328

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

699

1329

}

700

1330

701

1331

if(quit_now){

709

1339

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

710

1340

perror_plus("if_indextoname");

711

1341

} else {

712

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

713

ip, interface, port);

1342

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

1343

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

714

1344

}

715

1345

} else {

716

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

717

port);

1346

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

1347

ip, (uintmax_t)port);

718

1348

}

719

1349

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

720

1350

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

721

const char *pcret;

722

if(af == AF_INET6){

723

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

724

sizeof(addrstr));

725

} else {

726

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

727

sizeof(addrstr));

728

}

729

if(pcret == NULL){

730

perror_plus("inet_ntop");

731

} else {

732

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

733

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

734

}

735

}

736

}

737

738

if(quit_now){

739

errno = EINTR;

740

goto mandos_end;

741

}

742

743

if(af == AF_INET6){

744

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

745

} else {

746

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

747

}

748

if(ret < 0){

749

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

750

int e = errno;

751

perror_plus("connect");

752

errno = e;

753

}

754

goto mandos_end;

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

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;

760

1431

}

761

1432

762

1433

const char *out = mandos_protocol_version;

764

1435

while(true){

765

1436

size_t out_size = strlen(out);

766

1437

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

767

out_size - written));

1438

out_size - written));

768

1439

if(ret == -1){

769

1440

int e = errno;

770

1441

perror_plus("write");

790

1461

}

791

1462

792

1463

if(debug){

793

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

1464

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

794

1465

}

795

1466

796

1467

if(quit_now){

798

1469

goto mandos_end;

799

1470

}

800

1471

801

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

802

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);

803

1477

804

1478

if(quit_now){

805

1479

errno = EINTR;

816

1490

817

1491

if(ret != GNUTLS_E_SUCCESS){

818

1492

if(debug){

819

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

1493

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

820

1494

gnutls_perror(ret);

821

1495

}

822

1496

errno = EPROTO;

826

1500

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

827

1501

828

1502

if(debug){

829

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

830

ip);

1503

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1504

" %s\n", ip);

831

1505

}

832

1506

833

1507

while(true){

838

1512

}

839

1513

840

1514

buffer_capacity = incbuffer(&buffer, buffer_length,

841

buffer_capacity);

1515

buffer_capacity);

842

1516

if(buffer_capacity == 0){

843

1517

int e = errno;

844

1518

perror_plus("incbuffer");

871

1545

}

872

1546

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

873

1547

if(ret < 0){

874

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

1548

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

1549

"***\n");

875

1550

gnutls_perror(ret);

876

1551

errno = EPROTO;

877

1552

goto mandos_end;

878

1553

}

879

1554

break;

880

1555

default:

881

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

882

" encrypted session with Mandos server\n");

1556

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

1557

" encrypted session with Mandos server\n");

883

1558

gnutls_bye(session, GNUTLS_SHUT_RDWR);

884

1559

errno = EIO;

885

1560

goto mandos_end;

890

1565

}

891

1566

892

1567

if(debug){

893

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

1568

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

894

1569

}

895

1570

896

1571

if(quit_now){

908

1583

909

1584

if(buffer_length > 0){

910

1585

ssize_t decrypted_buffer_size;

911

decrypted_buffer_size = pgp_packet_decrypt(buffer,

912

buffer_length,

913

&decrypted_buffer);

1586

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1587

&decrypted_buffer, mc);

914

1588

if(decrypted_buffer_size >= 0){

915

1589

1590

clearerr(stdout);

916

1591

written = 0;

917

1592

while(written < (size_t) decrypted_buffer_size){

918

1593

if(quit_now){

926

1601

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

927

1602

int e = errno;

928

1603

if(debug){

929

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

930

strerror(errno));

1604

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

1605

strerror(errno));

931

1606

}

932

1607

errno = e;

933

1608

goto mandos_end;

934

1609

}

935

1610

written += (size_t)ret;

936

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

}

937

1622

retval = 0;

938

1623

}

939

1624

}

942

1627

943

1628

mandos_end:

944

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

}

945

1636

int e = errno;

946

1637

free(decrypted_buffer);

947

1638

free(buffer);

948

1639

if(tcp_sd >= 0){

949

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

1640

ret = close(tcp_sd);

950

1641

}

951

1642

if(ret == -1){

952

1643

if(e == 0){

977

1668

AVAHI_GCC_UNUSED AvahiStringList *txt,

978

1669

AVAHI_GCC_UNUSED AvahiLookupResultFlags

979

1670

flags,

980

AVAHI_GCC_UNUSED void* userdata){

981

assert(r);

1671

void *mc){

1672

if(r == NULL){

1673

return;

1674

}

982

1675

983

1676

/* Called whenever a service has been resolved successfully or

984

1677

timed out */

985

1678

986

1679

if(quit_now){

1680

avahi_s_service_resolver_free(r);

987

1681

return;

988

1682

}

989

1683

990

1684

switch(event){

991

1685

default:

992

1686

case AVAHI_RESOLVER_FAILURE:

993

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

994

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

995

avahi_strerror(avahi_server_errno(mc.server)));

1687

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

1688

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

1689

domain,

1690

avahi_strerror(avahi_server_errno

1691

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

996

1692

break;

997

1693

998

1694

case AVAHI_RESOLVER_FOUND:

1000

1696

char ip[AVAHI_ADDRESS_STR_MAX];

1001

1697

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

1002

1698

if(debug){

1003

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

1004

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

1005

ip, (intmax_t)interface, port);

1699

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

1700

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

1701

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

1006

1702

}

1007

int ret = start_mandos_communication(ip, port, interface,

1008

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);

1009

1707

if(ret == 0){

1010

avahi_simple_poll_quit(mc.simple_poll);

1708

avahi_simple_poll_quit(simple_poll);

1011

1709

} else {

1012

ret = add_server(ip, port, interface,

1013

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)){

1713

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

1714

" list\n", name);

1715

}

1014

1716

}

1015

1717

}

1016

1718

}

1026

1728

const char *domain,

1027

1729

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1028

1730

flags,

1029

AVAHI_GCC_UNUSED void* userdata){

1030

assert(b);

1731

void *mc){

1732

if(b == NULL){

1733

return;

1734

}

1031

1735

1032

1736

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

1033

1737

is removed from the LAN */

1040

1744

default:

1041

1745

case AVAHI_BROWSER_FAILURE:

1042

1746

1043

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

1044

avahi_strerror(avahi_server_errno(mc.server)));

1045

avahi_simple_poll_quit(mc.simple_poll);

1747

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

1748

avahi_strerror(avahi_server_errno

1749

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

1750

avahi_simple_poll_quit(simple_poll);

1046

1751

return;

1047

1752

1048

1753

case AVAHI_BROWSER_NEW:

1051

1756

the callback function is called the Avahi server will free the

1052

1757

resolver for us. */

1053

1758

1054

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

1055

name, type, domain, protocol, 0,

1056

resolve_callback, NULL) == NULL)

1057

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

1058

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

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)

1763

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

1764

" %s\n", name,

1765

avahi_strerror(avahi_server_errno

1766

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

1059

1767

break;

1060

1768

1061

1769

case AVAHI_BROWSER_REMOVE:

1064

1772

case AVAHI_BROWSER_ALL_FOR_NOW:

1065

1773

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1066

1774

if(debug){

1067

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

1775

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

1776

" searching...\n");

1068

1777

}

1069

1778

break;

1070

1779

}

1079

1788

signal_received = sig;

1080

1789

int old_errno = errno;

1081

1790

/* set main loop to exit */

1082

if(mc.simple_poll != NULL){

1083

avahi_simple_poll_quit(mc.simple_poll);

1791

if(simple_poll != NULL){

1792

avahi_simple_poll_quit(simple_poll);

1084

1793

}

1085

1794

errno = old_errno;

1086

1795

}

1087

1796

1797

__attribute__((nonnull, warn_unused_result))

1798

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

1799

int ret;

1800

int old_errno;

1801

1802

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

1803

if(s < 0){

1804

old_errno = errno;

1805

perror_plus("socket");

1806

errno = old_errno;

1807

return false;

1808

}

1809

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

1810

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

1811

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1812

if(ret == -1){

1813

if(debug){

1814

old_errno = errno;

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;

1822

}

1823

return false;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1829

}

1830

return true;

1831

}

1832

1833

__attribute__((nonnull, warn_unused_result))

1834

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

1835

1836

/* Reject the loopback device */

1837

if(ifr->ifr_flags & IFF_LOOPBACK){

1838

if(debug){

1839

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

1840

ifname);

1841

}

1842

return false;

1843

}

1844

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

1845

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

1846

if(debug){

1847

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

1848

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

1849

}

1850

return true;

1851

}

1852

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

1853

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

1854

if(debug){

1855

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1856

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

1857

}

1858

return false;

1859

}

1860

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

1861

if(ifr->ifr_flags & IFF_NOARP){

1862

if(debug){

1863

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

1864

ifname);

1865

}

1866

return false;

1867

}

1868

1869

/* Accept this device */

1870

if(debug){

1871

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

1872

}

1873

return true;

1874

}

1875

1088

1876

/*

1089

1877

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

1090

1878

* corresponds to an acceptable network device.

1091

1879

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

1092

1880

*/

1881

__attribute__((nonnull, warn_unused_result))

1093

1882

int good_interface(const struct dirent *if_entry){

1094

ssize_t ssret;

1095

char *flagname = NULL;

1096

1883

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

1097

1884

return 0;

1098

1885

}

1099

int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,

1100

if_entry->d_name);

1101

if(ret < 0){

1102

perror_plus("asprintf");

1103

return 0;

1104

}

1105

int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));

1106

if(flags_fd == -1){

1107

perror_plus("open");

1108

free(flagname);

1109

return 0;

1110

}

1111

free(flagname);

1112

typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */

1113

/* read line from flags_fd */

1114

ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */

1115

char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */

1116

flagstring[(size_t)to_read] = '\0';

1117

if(flagstring == NULL){

1118

perror_plus("malloc");

1119

close(flags_fd);

1120

return 0;

1121

}

1122

while(to_read > 0){

1123

ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,

1124

(size_t)to_read));

1125

if(ssret == -1){

1126

perror_plus("read");

1127

free(flagstring);

1128

close(flags_fd);

1129

return 0;

1130

}

1131

to_read -= ssret;

1132

if(ssret == 0){

1133

break;

1134

}

1135

}

1136

close(flags_fd);

1137

intmax_t tmpmax;

1138

char *tmp;

1139

errno = 0;

1140

tmpmax = strtoimax(flagstring, &tmp, 0);

1141

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

1142

and not (isspace(*tmp)))

1143

or tmpmax != (ifreq_flags)tmpmax){

1144

if(debug){

1145

fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",

1146

flagstring, if_entry->d_name);

1147

}

1148

free(flagstring);

1149

return 0;

1150

}

1151

free(flagstring);

1152

ifreq_flags flags = (ifreq_flags)tmpmax;

1153

/* Reject the loopback device */

1154

if(flags & IFF_LOOPBACK){

1155

if(debug){

1156

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

1157

if_entry->d_name);

1158

}

1159

return 0;

1160

}

1161

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

1162

if(connect_to != NULL and (flags & IFF_POINTOPOINT)){

1163

if(debug){

1164

fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",

1165

if_entry->d_name);

1166

}

1167

return 1;

1168

}

1169

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

1170

if(not (flags & IFF_BROADCAST)){

1171

if(debug){

1172

fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",

1173

if_entry->d_name);

1174

}

1175

return 0;

1176

}

1177

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

1178

if(flags & IFF_NOARP){

1179

if(debug){

1180

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

1181

if_entry->d_name);

1182

}

1183

return 0;

1184

}

1185

/* Accept this device */

1186

if(debug){

1187

fprintf(stderr, "Interface \"%s\" is acceptable\n",

1188

if_entry->d_name);

1886

1887

struct ifreq ifr;

1888

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

1889

if(debug){

1890

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

1891

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

1892

}

1893

return 0;

1894

}

1895

1896

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

1897

return 0;

1189

1898

}

1190

1899

return 1;

1191

1900

}

1192

1901

1902

/*

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))

1193

1937

int notdotentries(const struct dirent *direntry){

1194

1938

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

1195

1939

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

1201

1945

return 1;

1202

1946

}

1203

1947

1204

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1948

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

1949

__attribute__((nonnull, warn_unused_result))

1950

int runnable_hook(const struct dirent *direntry){

1951

int ret;

1952

size_t sret;

1953

struct stat st;

1954

1955

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

1956

/* Empty name? */

1957

return 0;

1958

}

1959

1960

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

1961

"abcdefghijklmnopqrstuvwxyz"

1962

"0123456789"

1963

"_.-");

1964

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

1965

/* Contains non-allowed characters */

1966

if(debug){

1967

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

1968

direntry->d_name);

1969

}

1970

return 0;

1971

}

1972

1973

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

1974

if(ret == -1){

1975

if(debug){

1976

perror_plus("Could not stat hook");

1977

}

1978

return 0;

1979

}

1980

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

1981

/* Not a regular file */

1982

if(debug){

1983

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

1984

direntry->d_name);

1985

}

1986

return 0;

1987

}

1988

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

1989

/* Not executable */

1990

if(debug){

1991

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

1992

direntry->d_name);

1993

}

1994

return 0;

1995

}

1996

if(debug){

1997

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

1998

direntry->d_name);

1999

}

2000

return 1;

2001

}

2002

2003

__attribute__((nonnull, warn_unused_result))

2004

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2005

mandos_context *mc){

1205

2006

int ret;

1206

2007

struct timespec now;

1207

2008

struct timespec waited_time;

1208

2009

intmax_t block_time;

1209

2010

1210

2011

while(true){

1211

if(mc.current_server == NULL){

1212

if (debug){

1213

fprintf(stderr,

1214

"Wait until first server is found. No timeout!\n");

2012

if(mc->current_server == NULL){

2013

if(debug){

2014

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

2015

" No timeout!\n");

1215

2016

}

1216

2017

ret = avahi_simple_poll_iterate(s, -1);

1217

2018

} else {

1218

if (debug){

1219

fprintf(stderr, "Check current_server if we should run it,"

1220

" or wait\n");

2019

if(debug){

2020

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

2021

" it, or wait\n");

1221

2022

}

1222

2023

/* the current time */

1223

2024

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1228

2029

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

1229

2030

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

1230

2031

waited_time.tv_sec = (now.tv_sec

1231

- mc.current_server->last_seen.tv_sec);

2032

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

1232

2033

waited_time.tv_nsec = (now.tv_nsec

1233

- mc.current_server->last_seen.tv_nsec);

2034

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

1234

2035

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

1235

2036

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

1236

2037

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

1238

2039

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

1239

2040

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

1240

2041

1241

if (debug){

1242

fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);

2042

if(debug){

2043

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

2044

block_time);

1243

2045

}

1244

2046

1245

2047

if(block_time <= 0){

1246

ret = start_mandos_communication(mc.current_server->ip,

1247

mc.current_server->port,

1248

mc.current_server->if_index,

1249

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);

1250

2052

if(ret == 0){

1251

avahi_simple_poll_quit(mc.simple_poll);

2053

avahi_simple_poll_quit(s);

1252

2054

return 0;

1253

2055

}

1254

2056

ret = clock_gettime(CLOCK_MONOTONIC,

1255

&mc.current_server->last_seen);

2057

&mc->current_server->last_seen);

1256

2058

if(ret == -1){

1257

2059

perror_plus("clock_gettime");

1258

2060

return -1;

1259

2061

}

1260

mc.current_server = mc.current_server->next;

2062

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

1261

2063

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

1262

2064

servers, but don't block */

1263

2065

}

1265

2067

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

1266

2068

}

1267

2069

if(ret != 0){

1268

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

2070

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

1269

2071

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

1270

2072

}

1271

2073

}

1272

2074

}

1273

2075

}

1274

2076

2077

__attribute__((nonnull))

2078

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

2079

const float delay){

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);

2103

if(numhooks == -1){

2104

perror_plus("scandir");

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){

2162

perror_plus("asprintf");

2163

_exit(EX_OSERR);

2164

}

2165

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

2166

if(ret == -1){

2167

free(delaystring);

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;

2460

}

2461

1275

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 };

1276

2476

AvahiSServiceBrowser *sb = NULL;

1277

int error;

2477

error_t ret_errno;

1278

2478

int ret;

1279

2479

intmax_t tmpmax;

1280

2480

char *tmp;

1281

2481

int exitcode = EXIT_SUCCESS;

1282

const char *interface = "";

1283

struct ifreq network;

1284

int sd = -1;

1285

bool take_down_interface = false;

1286

uid_t uid;

1287

gid_t gid;

1288

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

1289

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;

1290

2487

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1291

2488

const char *seckey = PATHDIR "/" SECKEY;

1292

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;

1293

2496

1294

2497

bool gnutls_initialized = false;

1295

2498

bool gpgme_initialized = false;

1341

2544

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

1342

2545

.arg = "FILE",

1343

2546

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

1344

.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 },

1345

2564

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

1346

2565

.arg = "BITS",

1347

2566

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

1348

2567

" Diffie-Hellman key exchange",

1349

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 },

1350

2574

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

1351

2575

.arg = "STRING",

1352

2576

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

1357

2581

.group = 2 },

1358

2582

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

1359

2583

.arg = "SECONDS",

1360

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

2584

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

2585

.group = 2 },

2586

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

2587

.arg = "DIR",

2588

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

1361

2589

.group = 2 },

1362

2590

/*

1363

2591

* These reproduce what we would get without ARGP_NO_HELP

1382

2610

connect_to = arg;

1383

2611

break;

1384

2612

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

1385

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

}

1386

2618

break;

1387

2619

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

1388

2620

seckey = arg;

1390

2622

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

1391

2623

pubkey = arg;

1392

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;

1393

2635

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

1394

2636

errno = 0;

1395

2637

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

1399

2641

}

1400

2642

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

1401

2643

break;

2644

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

2645

dh_params_file = arg;

2646

break;

1402

2647

case 130: /* --priority */

1403

2648

mc.priority = arg;

1404

2649

break;

1417

2662

argp_error(state, "Bad retry interval");

1418

2663

}

1419

2664

break;

2665

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

2666

hookdir = arg;

2667

break;

1420

2668

/*

1421

2669

* These reproduce what we would get without ARGP_NO_HELP

1422

2670

*/

1428

2676

argp_state_help(state, state->out_stream,

1429

2677

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

1430

2678

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

1431

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

2679

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

1432

2680

exit(argp_err_exit_status);

1433

2681

break;

1434

2682

default:

1441

2689

.args_doc = "",

1442

2690

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

1443

2691

" passwords from a Mandos server" };

1444

ret = argp_parse(&argp, argc, argv,

1445

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1446

switch(ret){

2692

ret_errno = argp_parse(&argp, argc, argv,

2693

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2694

switch(ret_errno){

1447

2695

case 0:

1448

2696

break;

1449

2697

case ENOMEM:

1450

2698

default:

1451

errno = ret;

2699

errno = ret_errno;

1452

2700

perror_plus("argp_parse");

1453

2701

exitcode = EX_OSERR;

1454

2702

goto end;

1457

2705

goto end;

1458

2706

}

1459

2707

}

1460

2708

1461

2709

{

1462

2710

/* Work around Debian bug #633582:

1463

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

1464

struct stat st;

1465

1466

/* Re-raise priviliges */

1467

errno = 0;

1468

ret = seteuid(0);

1469

if(ret == -1){

1470

perror_plus("seteuid");

1471

}

1472

1473

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

1474

int seckey_fd = open(seckey, O_RDONLY);

1475

if(seckey_fd == -1){

1476

perror_plus("open");

1477

} else {

1478

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

1479

if(ret == -1){

1480

perror_plus("fstat");

1481

} else {

1482

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1483

ret = fchown(seckey_fd, uid, gid);

1484

if(ret == -1){

1485

perror_plus("fchown");

1486

}

1487

}

1488

}

1489

TEMP_FAILURE_RETRY(close(seckey_fd));

1490

}

1491

}

1492

1493

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

1494

int pubkey_fd = open(pubkey, O_RDONLY);

1495

if(pubkey_fd == -1){

1496

perror_plus("open");

1497

} else {

1498

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

1499

if(ret == -1){

1500

perror_plus("fstat");

1501

} else {

1502

if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){

1503

ret = fchown(pubkey_fd, uid, gid);

1504

if(ret == -1){

1505

perror_plus("fchown");

1506

}

1507

}

1508

}

1509

TEMP_FAILURE_RETRY(close(pubkey_fd));

1510

}

1511

}

1512

1513

/* Lower privileges */

1514

errno = 0;

1515

ret = seteuid(uid);

1516

if(ret == -1){

1517

perror_plus("seteuid");

1518

}

2711

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

2712

2713

/* Re-raise privileges */

2714

ret = raise_privileges();

2715

if(ret != 0){

2716

errno = ret;

2717

perror_plus("Failed to raise privileges");

2718

} else {

2719

struct stat st;

2720

2721

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

2722

int seckey_fd = open(seckey, O_RDONLY);

2723

if(seckey_fd == -1){

2724

perror_plus("open");

2725

} else {

2726

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

2727

if(ret == -1){

2728

perror_plus("fstat");

2729

} else {

2730

if(S_ISREG(st.st_mode)

2731

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

2732

ret = fchown(seckey_fd, uid, gid);

2733

if(ret == -1){

2734

perror_plus("fchown");

2735

}

2736

}

2737

}

2738

close(seckey_fd);

2739

}

2740

}

2741

2742

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

2743

int pubkey_fd = open(pubkey, O_RDONLY);

2744

if(pubkey_fd == -1){

2745

perror_plus("open");

2746

} else {

2747

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

2748

if(ret == -1){

2749

perror_plus("fstat");

2750

} else {

2751

if(S_ISREG(st.st_mode)

2752

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

2753

ret = fchown(pubkey_fd, uid, gid);

2754

if(ret == -1){

2755

perror_plus("fchown");

2756

}

2757

}

2758

}

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

2785

/* Lower privileges */

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;

2807

}

2808

}

2809

}

2810

2811

/* Run network hooks */

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);

1519

2824

}

1520

2825

1521

2826

if(not debug){

1522

2827

avahi_set_log_function(empty_log);

1523

2828

}

1524

1525

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

1526

struct dirent **direntries;

1527

ret = scandir(sys_class_net, &direntries, good_interface,

1528

alphasort);

1529

if(ret >= 1){

1530

/* Pick the first good interface */

1531

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

1532

if(debug){

1533

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

1534

}

1535

if(interface == NULL){

1536

perror_plus("malloc");

1537

free(direntries);

1538

exitcode = EXIT_FAILURE;

1539

goto end;

1540

}

1541

free(direntries);

1542

} else {

1543

free(direntries);

1544

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

1545

exitcode = EXIT_FAILURE;

1546

goto end;

1547

}

1548

}

1549

2829

1550

2830

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

1551

2831

from the signal handler */

1552

2832

/* Initialize the pseudo-RNG for Avahi */

1553

2833

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

1554

mc.simple_poll = avahi_simple_poll_new();

1555

if(mc.simple_poll == NULL){

1556

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

2834

simple_poll = avahi_simple_poll_new();

2835

if(simple_poll == NULL){

2836

fprintf_plus(stderr,

2837

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

1557

2838

exitcode = EX_UNAVAILABLE;

1558

2839

goto end;

1559

2840

}

1621

2902

}

1622

2903

}

1623

2904

1624

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

1625

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

1626

if_index = (AvahiIfIndex) if_nametoindex(interface);

1627

if(if_index == 0){

1628

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

1629

exitcode = EX_UNAVAILABLE;

1630

goto end;

1631

}

1632

1633

if(quit_now){

1634

goto end;

1635

}

1636

1637

/* Re-raise priviliges */

1638

errno = 0;

1639

ret = seteuid(0);

1640

if(ret == -1){

1641

perror_plus("seteuid");

1642

}

1643

1644

#ifdef __linux__

1645

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1646

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

1647

ret = klogctl(8, NULL, 5);

1648

bool restore_loglevel = true;

1649

if(ret == -1){

1650

restore_loglevel = false;

1651

perror_plus("klogctl");

1652

}

1653

#endif /* __linux__ */

1654

1655

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1656

if(sd < 0){

1657

perror_plus("socket");

1658

exitcode = EX_OSERR;

1659

#ifdef __linux__

1660

if(restore_loglevel){

1661

ret = klogctl(7, NULL, 0);

1662

if(ret == -1){

1663

perror_plus("klogctl");

1664

}

1665

}

1666

#endif /* __linux__ */

1667

/* Lower privileges */

1668

errno = 0;

1669

ret = seteuid(uid);

1670

if(ret == -1){

1671

perror_plus("seteuid");

1672

}

1673

goto end;

1674

}

1675

strcpy(network.ifr_name, interface);

1676

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

1677

if(ret == -1){

1678

perror_plus("ioctl SIOCGIFFLAGS");

1679

#ifdef __linux__

1680

if(restore_loglevel){

1681

ret = klogctl(7, NULL, 0);

1682

if(ret == -1){

1683

perror_plus("klogctl");

1684

}

1685

}

1686

#endif /* __linux__ */

1687

exitcode = EX_OSERR;

1688

/* Lower privileges */

1689

errno = 0;

1690

ret = seteuid(uid);

1691

if(ret == -1){

1692

perror_plus("seteuid");

1693

}

1694

goto end;

1695

}

1696

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

1697

network.ifr_flags |= IFF_UP;

1698

take_down_interface = true;

1699

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

1700

if(ret == -1){

1701

take_down_interface = false;

1702

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1703

exitcode = EX_OSERR;

1704

#ifdef __linux__

1705

if(restore_loglevel){

1706

ret = klogctl(7, NULL, 0);

1707

if(ret == -1){

1708

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;

1709

2956

}

1710

2957

}

1711

#endif /* __linux__ */

1712

/* Lower privileges */

1713

errno = 0;

1714

ret = seteuid(uid);

1715

if(ret == -1){

1716

perror_plus("seteuid");

1717

}

1718

goto end;

1719

}

1720

}

1721

/* Sleep checking until interface is running.

1722

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

1723

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

1724

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

1725

if(ret == -1){

1726

perror_plus("ioctl SIOCGIFFLAGS");

1727

} else if(network.ifr_flags & IFF_RUNNING){

1728

2958

break;

1729

2959

}

1730

struct timespec sleeptime = { .tv_nsec = 250000000 };

1731

ret = nanosleep(&sleeptime, NULL);

1732

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

1733

perror_plus("nanosleep");

1734

}

1735

}

1736

if(not take_down_interface){

1737

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

1738

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

1739

if(ret == -1){

1740

perror_plus("close");

1741

}

1742

}

1743

#ifdef __linux__

1744

if(restore_loglevel){

1745

/* Restores kernel loglevel to default */

1746

ret = klogctl(7, NULL, 0);

1747

if(ret == -1){

1748

perror_plus("klogctl");

1749

}

1750

}

1751

#endif /* __linux__ */

1752

/* Lower privileges */

1753

errno = 0;

1754

if(take_down_interface){

1755

/* Lower privileges */

1756

ret = seteuid(uid);

1757

if(ret == -1){

1758

perror_plus("seteuid");

1759

}

1760

} else {

1761

/* Lower privileges permanently */

1762

ret = setuid(uid);

1763

if(ret == -1){

1764

perror_plus("setuid");

1765

}

1766

}

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);

1767

2988

}

1768

2989

1769

2990

if(quit_now){

1770

2991

goto end;

1771

2992

}

1772

2993

1773

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

1774

3001

if(ret == -1){

1775

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

3002

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

1776

3003

exitcode = EX_UNAVAILABLE;

1777

3004

goto end;

1778

3005

} else {

1783

3010

goto end;

1784

3011

}

1785

3012

1786

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){

1787

3023

perror_plus("mkdtemp");

1788

3024

goto end;

1789

3025

}

1790

tempdir_created = true;

1791

3026

1792

3027

if(quit_now){

1793

3028

goto end;

1794

3029

}

1795

3030

1796

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

1797

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

3031

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

3032

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

1798

3033

exitcode = EX_UNAVAILABLE;

1799

3034

goto end;

1800

3035

} else {

1809

3044

/* Connect directly, do not use Zeroconf */

1810

3045

/* (Mainly meant for debugging) */

1811

3046

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

3047

1812

3048

if(address == NULL){

1813

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

3049

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

1814

3050

exitcode = EX_USAGE;

1815

3051

goto end;

1816

3052

}

1819

3055

goto end;

1820

3056

}

1821

3057

1822

uint16_t port;

3058

in_port_t port;

1823

3059

errno = 0;

1824

3060

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

1825

3061

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

1826

or tmpmax != (uint16_t)tmpmax){

1827

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

3062

or tmpmax != (in_port_t)tmpmax){

3063

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

1828

3064

exitcode = EX_USAGE;

1829

3065

goto end;

1830

3066

}

1831

3067

1832

3068

if(quit_now){

1833

3069

goto end;

1834

3070

}

1835

3071

1836

port = (uint16_t)tmpmax;

3072

port = (in_port_t)tmpmax;

1837

3073

*address = '\0';

1838

3074

/* Colon in address indicates IPv6 */

1839

3075

int af;

1855

3091

}

1856

3092

1857

3093

while(not quit_now){

1858

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

3094

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

3095

&mc);

1859

3096

if(quit_now or ret == 0){

1860

3097

break;

1861

3098

}

1862

3099

if(debug){

1863

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

1864

(int)retry_interval);

3100

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

3101

(int)retry_interval);

1865

3102

}

1866

sleep((int)retry_interval);

3103

sleep((unsigned int)retry_interval);

1867

3104

}

1868

3105

1869

if (not quit_now){

3106

if(not quit_now){

1870

3107

exitcode = EXIT_SUCCESS;

1871

3108

}

1872

3109

1873

3110

goto end;

1874

3111

}

1875

3112

1887

3124

config.publish_domain = 0;

1888

3125

1889

3126

/* Allocate a new server */

1890

mc.server = avahi_server_new(avahi_simple_poll_get

1891

(mc.simple_poll), &config, NULL,

1892

NULL, &error);

3127

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3128

&config, NULL, NULL, &ret);

1893

3129

1894

3130

/* Free the Avahi configuration data */

1895

3131

avahi_server_config_free(&config);

1897

3133

1898

3134

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

1899

3135

if(mc.server == NULL){

1900

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

1901

avahi_strerror(error));

3136

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

3137

avahi_strerror(ret));

1902

3138

exitcode = EX_UNAVAILABLE;

1903

3139

goto end;

1904

3140

}

1910

3146

/* Create the Avahi service browser */

1911

3147

sb = avahi_s_service_browser_new(mc.server, if_index,

1912

3148

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1913

NULL, 0, browse_callback, NULL);

3149

NULL, 0, browse_callback,

3150

(void *)&mc);

1914

3151

if(sb == NULL){

1915

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

1916

avahi_strerror(avahi_server_errno(mc.server)));

3152

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

3153

avahi_strerror(avahi_server_errno(mc.server)));

1917

3154

exitcode = EX_UNAVAILABLE;

1918

3155

goto end;

1919

3156

}

1925

3162

/* Run the main loop */

1926

3163

1927

3164

if(debug){

1928

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

3165

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

1929

3166

}

1930

1931

ret = avahi_loop_with_timeout(mc.simple_poll,

1932

(int)(retry_interval * 1000));

3167

3168

ret = avahi_loop_with_timeout(simple_poll,

3169

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

1933

3170

if(debug){

1934

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

1935

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

3171

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

3172

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

1936

3173

}

1937

3174

1938

3175

end:

1939

3176

1940

3177

if(debug){

1941

fprintf(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

}

1942

3185

}

1943

3186

1944

3187

/* Cleanup things */

3188

free(mc.interfaces);

3189

1945

3190

if(sb != NULL)

1946

3191

avahi_s_service_browser_free(sb);

1947

3192

1948

3193

if(mc.server != NULL)

1949

3194

avahi_server_free(mc.server);

1950

3195

1951

if(mc.simple_poll != NULL)

1952

avahi_simple_poll_free(mc.simple_poll);

3196

if(simple_poll != NULL)

3197

avahi_simple_poll_free(simple_poll);

1953

3198

1954

3199

if(gnutls_initialized){

1955

3200

gnutls_certificate_free_credentials(mc.cred);

1956

gnutls_global_deinit();

1957

3201

gnutls_dh_params_deinit(mc.dh_params);

1958

3202

}

1959

3203

1960

3204

if(gpgme_initialized){

1961

3205

gpgme_release(mc.ctx);

1962

3206

}

1963

3207

1964

3208

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

1965

3209

has seen */

1966

3210

if(mc.current_server != NULL){

1967

3211

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

1968

3212

while(mc.current_server != NULL){

1969

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

1970

3222

free(mc.current_server);

1971

3223

mc.current_server = next;

1972

3224

}

1973

3225

}

1974

3226

1975

/* Take down the network interface */

1976

if(take_down_interface){

1977

/* Re-raise priviliges */

1978

errno = 0;

1979

ret = seteuid(0);

1980

if(ret == -1){

1981

perror_plus("seteuid");

1982

}

1983

if(geteuid() == 0){

1984

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

1985

if(ret == -1){

1986

perror_plus("ioctl SIOCGIFFLAGS");

1987

} else if(network.ifr_flags & IFF_UP) {

1988

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

1989

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

1990

if(ret == -1){

1991

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1992

}

1993

}

1994

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

1995

if(ret == -1){

1996

perror_plus("close");

1997

}

1998

/* Lower privileges permanently */

1999

errno = 0;

2000

ret = setuid(uid);

2001

if(ret == -1){

2002

perror_plus("setuid");

2003

}

2004

}

3227

/* Re-raise privileges */

3228

{

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

}

3256

}

3257

3258

ret = lower_privileges_permanently();

3259

if(ret != 0){

3260

errno = ret;

3261

perror_plus("Failed to lower privileges permanently");

3262

}

3263

}

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);

2005

3320

}

2006

3321

2007

3322

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

2008

if(tempdir_created){

2009

struct dirent **direntries = NULL;

2010

struct dirent *direntry = NULL;

2011

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

2012

alphasort);

2013

if (numentries > 0){

2014

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

2015

direntry = direntries[i];

2016

char *fullname = NULL;

2017

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

2018

direntry->d_name);

2019

if(ret < 0){

2020

perror_plus("asprintf");

2021

continue;

2022

}

2023

ret = remove(fullname);

2024

if(ret == -1){

2025

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

2026

strerror(errno));

2027

}

2028

free(fullname);

2029

}

2030

}

2031

2032

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

2033

free(direntries);

2034

if (numentries == -1){

2035

perror_plus("scandir");

2036

}

2037

ret = rmdir(tempdir);

2038

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

2039

perror_plus("rmdir");

2040

}

3323

if(tempdir != NULL){

3324

clean_dir_at(-1, tempdir, 0);

2041

3325

}

2042

3326

2043

3327

if(quit_now){