/mandos/release : revision 237.7.778

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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@fukt.bsnet.se>.

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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, program_invocation_short_name */

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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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SIOCSIFFLAGS, if_indextoname(),

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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 */

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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_version = "mandos-client " VERSION;

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

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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 circular linked when ever used */

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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", .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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fprintf(stderr, "Mandos plugin %s: ", program_invocation_short_name);

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

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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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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}

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/* uniqe case of first server */

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if (mc.current_server == NULL){

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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(*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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/* Placing 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))

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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;

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}

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errno = old_errno;

308

return ret;

309

}

310

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

312

__attribute__((warn_unused_result))

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int lower_privileges(void){

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int old_errno = errno;

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int ret = 0;

316

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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/* Lower privileges permanently */

324

__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

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int old_errno = errno;

327

int ret = 0;

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

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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.

226

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*/

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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,

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const char * const pubkey,

341

const char * const tempdir,

342

mandos_context *mc){

229

343

gpgme_error_t rc;

230

344

gpgme_engine_info_t engine_info;

231

345

232

233

346

/*

234

347

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

235

348

*/

236

bool import_key(const char *filename){

349

bool import_key(const char * const filename){

237

350

int ret;

238

351

int fd;

239

352

gpgme_data_t pgp_data;

244

357

return false;

245

358

}

246

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

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

400

perror_plus("clock_settime");

401

}

402

ret = lower_privileges();

403

if(ret != 0){

404

errno = ret;

405

perror_plus("Failed to lower privileges");

406

}

407

} while(false);

408

247

409

rc = gpgme_data_new_from_fd(&pgp_data, fd);

248

410

if(rc != GPG_ERR_NO_ERROR){

249

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

250

gpgme_strsource(rc), gpgme_strerror(rc));

411

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

412

gpgme_strsource(rc), gpgme_strerror(rc));

251

413

return false;

252

414

}

253

415

254

rc = gpgme_op_import(mc.ctx, pgp_data);

416

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

255

417

if(rc != GPG_ERR_NO_ERROR){

256

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

257

gpgme_strsource(rc), gpgme_strerror(rc));

418

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

419

gpgme_strsource(rc), gpgme_strerror(rc));

258

420

return false;

259

421

}

422

{

423

gpgme_import_result_t import_result

424

= gpgme_op_import_result(mc->ctx);

425

if((import_result->imported < 1

426

or import_result->not_imported > 0)

427

and import_result->unchanged == 0){

428

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

429

fprintf_plus(stderr,

430

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

431

import_result->considered);

432

fprintf_plus(stderr,

433

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

434

import_result->no_user_id);

435

fprintf_plus(stderr,

436

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

437

import_result->imported);

438

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

439

import_result->imported_rsa);

440

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

441

import_result->unchanged);

442

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

443

import_result->new_user_ids);

444

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

445

import_result->new_sub_keys);

446

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

447

import_result->new_signatures);

448

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

449

import_result->new_revocations);

450

fprintf_plus(stderr,

451

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

452

import_result->secret_read);

453

fprintf_plus(stderr,

454

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

455

import_result->secret_imported);

456

fprintf_plus(stderr,

457

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

458

import_result->secret_unchanged);

459

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

460

import_result->not_imported);

461

for(gpgme_import_status_t import_status

462

= import_result->imports;

463

import_status != NULL;

464

import_status = import_status->next){

465

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

466

import_status->fpr);

467

if(import_status->result != GPG_ERR_NO_ERROR){

468

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

469

gpgme_strsource(import_status->result),

470

gpgme_strerror(import_status->result));

471

}

472

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

473

fprintf_plus(stderr,

474

import_status->status & GPGME_IMPORT_NEW

475

? "The key was new.\n"

476

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

477

fprintf_plus(stderr,

478

import_status->status & GPGME_IMPORT_UID

479

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

480

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

481

fprintf_plus(stderr,

482

import_status->status & GPGME_IMPORT_SIG

483

? "The key contained new signatures.\n"

484

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

485

fprintf_plus(stderr,

486

import_status->status & GPGME_IMPORT_SUBKEY

487

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

488

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

489

fprintf_plus(stderr,

490

import_status->status & GPGME_IMPORT_SECRET

491

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

492

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

493

}

494

return false;

495

}

496

}

260

497

261

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

498

ret = close(fd);

262

499

if(ret == -1){

263

500

perror_plus("close");

264

501

}

267

504

}

268

505

269

506

if(debug){

270

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

507

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

271

508

}

272

509

273

510

/* Init GPGME */

274

511

gpgme_check_version(NULL);

275

512

rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);

276

513

if(rc != GPG_ERR_NO_ERROR){

277

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

278

gpgme_strsource(rc), gpgme_strerror(rc));

514

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

515

gpgme_strsource(rc), gpgme_strerror(rc));

279

516

return false;

280

517

}

281

518

282

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

519

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

283

520

rc = gpgme_get_engine_info(&engine_info);

284

521

if(rc != GPG_ERR_NO_ERROR){

285

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

286

gpgme_strsource(rc), gpgme_strerror(rc));

522

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

523

gpgme_strsource(rc), gpgme_strerror(rc));

287

524

return false;

288

525

}

289

526

while(engine_info != NULL){

295

532

engine_info = engine_info->next;

296

533

}

297

534

if(engine_info == NULL){

298

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

535

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

536

tempdir);

299

537

return false;

300

538

}

301

539

302

540

/* Create new GPGME "context" */

303

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

541

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

304

542

if(rc != GPG_ERR_NO_ERROR){

305

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

306

gpgme_strsource(rc), gpgme_strerror(rc));

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

307

545

return false;

308

546

}

309

547

318

556

* Decrypt OpenPGP data.

319

557

* Returns -1 on error

320

558

*/

559

__attribute__((nonnull, warn_unused_result))

321

560

static ssize_t pgp_packet_decrypt(const char *cryptotext,

322

561

size_t crypto_size,

323

char **plaintext){

562

char **plaintext,

563

mandos_context *mc){

324

564

gpgme_data_t dh_crypto, dh_plain;

325

565

gpgme_error_t rc;

326

566

ssize_t ret;

328

568

ssize_t plaintext_length = 0;

329

569

330

570

if(debug){

331

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

571

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

332

572

}

333

573

334

574

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

335

575

rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,

336

576

0);

337

577

if(rc != GPG_ERR_NO_ERROR){

338

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

339

gpgme_strsource(rc), gpgme_strerror(rc));

578

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

579

gpgme_strsource(rc), gpgme_strerror(rc));

340

580

return -1;

341

581

}

342

582

343

583

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

344

584

rc = gpgme_data_new(&dh_plain);

345

585

if(rc != GPG_ERR_NO_ERROR){

346

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

347

gpgme_strsource(rc), gpgme_strerror(rc));

586

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

587

gpgme_strsource(rc), gpgme_strerror(rc));

348

588

gpgme_data_release(dh_crypto);

349

589

return -1;

350

590

}

351

591

352

592

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

353

593

data buffer */

354

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

594

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

355

595

if(rc != GPG_ERR_NO_ERROR){

356

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

357

gpgme_strsource(rc), gpgme_strerror(rc));

596

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

597

gpgme_strsource(rc), gpgme_strerror(rc));

358

598

plaintext_length = -1;

359

599

if(debug){

360

600

gpgme_decrypt_result_t result;

361

result = gpgme_op_decrypt_result(mc.ctx);

601

result = gpgme_op_decrypt_result(mc->ctx);

362

602

if(result == NULL){

363

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

603

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

364

604

} else {

365

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

366

result->unsupported_algorithm);

367

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

368

result->wrong_key_usage);

605

if(result->unsupported_algorithm != NULL) {

606

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

607

result->unsupported_algorithm);

608

}

609

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

610

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

369

611

if(result->file_name != NULL){

370

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

612

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

371

613

}

372

gpgme_recipient_t recipient;

373

recipient = result->recipients;

374

while(recipient != NULL){

375

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

376

gpgme_pubkey_algo_name(recipient->pubkey_algo));

377

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

378

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

379

recipient->status == GPG_ERR_NO_SECKEY

380

? "No" : "Yes");

381

recipient = recipient->next;

614

615

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

616

r = r->next){

617

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

618

gpgme_pubkey_algo_name(r->pubkey_algo));

619

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

620

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

621

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

382

622

}

383

623

}

384

624

}

386

626

}

387

627

388

628

if(debug){

389

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

629

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

390

630

}

391

631

392

632

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

399

639

*plaintext = NULL;

400

640

while(true){

401

641

plaintext_capacity = incbuffer(plaintext,

402

(size_t)plaintext_length,

403

plaintext_capacity);

642

(size_t)plaintext_length,

643

plaintext_capacity);

404

644

if(plaintext_capacity == 0){

405

perror_plus("incbuffer");

406

plaintext_length = -1;

407

goto decrypt_end;

645

perror_plus("incbuffer");

646

plaintext_length = -1;

647

goto decrypt_end;

408

648

}

409

649

410

650

ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,

423

663

}

424

664

425

665

if(debug){

426

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

666

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

427

667

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

428

668

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

429

669

}

440

680

return plaintext_length;

441

681

}

442

682

443

static const char * safer_gnutls_strerror(int value){

444

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

445

-Wunreachable-code */

446

if(ret == NULL)

447

ret = "(unknown)";

448

return ret;

683

__attribute__((warn_unused_result, const))

684

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

685

if(str == NULL)

686

return "(unknown)";

687

return str;

688

}

689

690

__attribute__((warn_unused_result))

691

static const char *safer_gnutls_strerror(int value){

692

const char *ret = gnutls_strerror(value);

693

return safe_string(ret);

449

694

}

450

695

451

696

/* GnuTLS log function callback */

697

__attribute__((nonnull))

452

698

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

453

699

const char* string){

454

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

700

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

455

701

}

456

702

703

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

457

704

static int init_gnutls_global(const char *pubkeyfilename,

458

const char *seckeyfilename){

705

const char *seckeyfilename,

706

const char *dhparamsfilename,

707

mandos_context *mc){

459

708

int ret;

460

709

461

710

if(debug){

462

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

463

}

464

465

ret = gnutls_global_init();

466

if(ret != GNUTLS_E_SUCCESS){

467

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

468

safer_gnutls_strerror(ret));

469

return -1;

711

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

470

712

}

471

713

472

714

if(debug){

478

720

}

479

721

480

722

/* OpenPGP credentials */

481

gnutls_certificate_allocate_credentials(&mc.cred);

723

ret = gnutls_certificate_allocate_credentials(&mc->cred);

482

724

if(ret != GNUTLS_E_SUCCESS){

483

fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning

484

from

485

-Wunreachable-code

486

*/

487

safer_gnutls_strerror(ret));

488

gnutls_global_deinit();

725

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

726

safer_gnutls_strerror(ret));

489

727

return -1;

490

728

}

491

729

492

730

if(debug){

493

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

494

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

495

seckeyfilename);

731

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

732

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

733

pubkeyfilename,

734

seckeyfilename);

496

735

}

497

736

737

#if GNUTLS_VERSION_NUMBER >= 0x030606

738

ret = gnutls_certificate_set_rawpk_key_file

739

(mc->cred, pubkeyfilename, seckeyfilename,

740

GNUTLS_X509_FMT_PEM, /* format */

741

NULL, /* pass */

742

/* key_usage */

743

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

744

NULL, /* names */

745

0, /* names_length */

746

/* privkey_flags */

747

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

748

0); /* pkcs11_flags */

749

#elif GNUTLS_VERSION_NUMBER < 0x030600

498

750

ret = gnutls_certificate_set_openpgp_key_file

499

(mc.cred, pubkeyfilename, seckeyfilename,

751

(mc->cred, pubkeyfilename, seckeyfilename,

500

752

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

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

755

#endif

501

756

if(ret != GNUTLS_E_SUCCESS){

502

fprintf(stderr,

503

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

504

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

505

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

506

safer_gnutls_strerror(ret));

757

fprintf_plus(stderr,

758

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

759

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

760

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

761

safer_gnutls_strerror(ret));

507

762

goto globalfail;

508

763

}

509

764

510

765

/* GnuTLS server initialization */

511

ret = gnutls_dh_params_init(&mc.dh_params);

512

if(ret != GNUTLS_E_SUCCESS){

513

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

514

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

515

goto globalfail;

516

}

517

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

518

if(ret != GNUTLS_E_SUCCESS){

519

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

520

safer_gnutls_strerror(ret));

521

goto globalfail;

522

}

523

524

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

766

ret = gnutls_dh_params_init(&mc->dh_params);

767

if(ret != GNUTLS_E_SUCCESS){

768

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

769

" initialization: %s\n",

770

safer_gnutls_strerror(ret));

771

goto globalfail;

772

}

773

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

774

if(dhparamsfilename != NULL){

775

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

776

do {

777

int dhpfile = open(dhparamsfilename, O_RDONLY);

778

if(dhpfile == -1){

779

perror_plus("open");

780

dhparamsfilename = NULL;

781

break;

782

}

783

size_t params_capacity = 0;

784

while(true){

785

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

786

(size_t)params.size,

787

(size_t)params_capacity);

788

if(params_capacity == 0){

789

perror_plus("incbuffer");

790

free(params.data);

791

params.data = NULL;

792

dhparamsfilename = NULL;

793

break;

794

}

795

ssize_t bytes_read = read(dhpfile,

796

params.data + params.size,

797

BUFFER_SIZE);

798

/* EOF */

799

if(bytes_read == 0){

800

break;

801

}

802

/* check bytes_read for failure */

803

if(bytes_read < 0){

804

perror_plus("read");

805

free(params.data);

806

params.data = NULL;

807

dhparamsfilename = NULL;

808

break;

809

}

810

params.size += (unsigned int)bytes_read;

811

}

812

ret = close(dhpfile);

813

if(ret == -1){

814

perror_plus("close");

815

}

816

if(params.data == NULL){

817

dhparamsfilename = NULL;

818

}

819

if(dhparamsfilename == NULL){

820

break;

821

}

822

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

823

GNUTLS_X509_FMT_PEM);

824

if(ret != GNUTLS_E_SUCCESS){

825

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

826

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

827

safer_gnutls_strerror(ret));

828

dhparamsfilename = NULL;

829

}

830

free(params.data);

831

} while(false);

832

}

833

if(dhparamsfilename == NULL){

834

if(mc->dh_bits == 0){

835

#if GNUTLS_VERSION_NUMBER < 0x030600

836

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

837

/* Try to read the private key file */

838

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

839

do {

840

int secfile = open(seckeyfilename, O_RDONLY);

841

if(secfile == -1){

842

perror_plus("open");

843

break;

844

}

845

size_t buffer_capacity = 0;

846

while(true){

847

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

848

(size_t)buffer.size,

849

(size_t)buffer_capacity);

850

if(buffer_capacity == 0){

851

perror_plus("incbuffer");

852

free(buffer.data);

853

buffer.data = NULL;

854

break;

855

}

856

ssize_t bytes_read = read(secfile,

857

buffer.data + buffer.size,

858

BUFFER_SIZE);

859

/* EOF */

860

if(bytes_read == 0){

861

break;

862

}

863

/* check bytes_read for failure */

864

if(bytes_read < 0){

865

perror_plus("read");

866

free(buffer.data);

867

buffer.data = NULL;

868

break;

869

}

870

buffer.size += (unsigned int)bytes_read;

871

}

872

close(secfile);

873

} while(false);

874

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

875

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

876

if(buffer.data != NULL){

877

{

878

gnutls_openpgp_privkey_t privkey = NULL;

879

ret = gnutls_openpgp_privkey_init(&privkey);

880

if(ret != GNUTLS_E_SUCCESS){

881

fprintf_plus(stderr, "Error initializing OpenPGP key"

882

" structure: %s",

883

safer_gnutls_strerror(ret));

884

free(buffer.data);

885

buffer.data = NULL;

886

} else {

887

ret = gnutls_openpgp_privkey_import

888

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

889

if(ret != GNUTLS_E_SUCCESS){

890

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

891

safer_gnutls_strerror(ret));

892

privkey = NULL;

893

}

894

free(buffer.data);

895

buffer.data = NULL;

896

if(privkey != NULL){

897

/* Use private key to suggest an appropriate

898

sec_param */

899

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

900

gnutls_openpgp_privkey_deinit(privkey);

901

if(debug){

902

fprintf_plus(stderr, "This OpenPGP key implies using"

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)));

906

}

907

}

908

}

909

}

910

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

911

/* Err on the side of caution */

912

sec_param = GNUTLS_SEC_PARAM_ULTRA;

913

if(debug){

914

fprintf_plus(stderr, "Falling back to security parameter"

915

" \"%s\"\n",

916

safe_string(gnutls_sec_param_get_name

917

(sec_param)));

918

}

919

}

920

}

921

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

922

if(uret != 0){

923

mc->dh_bits = uret;

924

if(debug){

925

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

926

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

927

safe_string(gnutls_sec_param_get_name

928

(sec_param)),

929

mc->dh_bits);

930

}

931

} else {

932

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

933

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

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)),

936

safer_gnutls_strerror(ret));

937

goto globalfail;

938

}

939

#endif

940

} else { /* dh_bits != 0 */

941

if(debug){

942

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

943

mc->dh_bits);

944

}

945

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

946

if(ret != GNUTLS_E_SUCCESS){

947

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

948

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

949

safer_gnutls_strerror(ret));

950

goto globalfail;

951

}

952

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

953

}

954

}

525

955

526

956

return 0;

527

957

528

958

globalfail:

529

959

530

gnutls_certificate_free_credentials(mc.cred);

531

gnutls_global_deinit();

532

gnutls_dh_params_deinit(mc.dh_params);

960

gnutls_certificate_free_credentials(mc->cred);

961

gnutls_dh_params_deinit(mc->dh_params);

533

962

return -1;

534

963

}

535

964

536

static int init_gnutls_session(gnutls_session_t *session){

965

__attribute__((nonnull, warn_unused_result))

966

static int init_gnutls_session(gnutls_session_t *session,

967

mandos_context *mc){

537

968

int ret;

538

969

/* GnuTLS session creation */

539

970

do {

540

ret = gnutls_init(session, GNUTLS_SERVER);

971

ret = gnutls_init(session, (GNUTLS_SERVER

972

#if GNUTLS_VERSION_NUMBER >= 0x030506

973

| GNUTLS_NO_TICKETS

974

#endif

975

#if GNUTLS_VERSION_NUMBER >= 0x030606

976

| GNUTLS_ENABLE_RAWPK

977

#endif

978

));

541

979

if(quit_now){

542

980

return -1;

543

981

}

544

982

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

545

983

if(ret != GNUTLS_E_SUCCESS){

546

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

547

safer_gnutls_strerror(ret));

984

fprintf_plus(stderr,

985

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

986

safer_gnutls_strerror(ret));

548

987

}

549

988

550

989

{

551

990

const char *err;

552

991

do {

553

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

992

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

554

993

if(quit_now){

555

994

gnutls_deinit(*session);

556

995

return -1;

557

996

}

558

997

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

559

998

if(ret != GNUTLS_E_SUCCESS){

560

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

561

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

562

safer_gnutls_strerror(ret));

999

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

1000

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

1001

safer_gnutls_strerror(ret));

563

1002

gnutls_deinit(*session);

564

1003

return -1;

565

1004

}

567

1006

568

1007

do {

569

1008

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

570

mc.cred);

1009

mc->cred);

571

1010

if(quit_now){

572

1011

gnutls_deinit(*session);

573

1012

return -1;

574

1013

}

575

1014

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

576

1015

if(ret != GNUTLS_E_SUCCESS){

577

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

578

safer_gnutls_strerror(ret));

1016

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

1017

safer_gnutls_strerror(ret));

579

1018

gnutls_deinit(*session);

580

1019

return -1;

581

1020

}

583

1022

/* ignore client certificate if any. */

584

1023

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

585

1024

586

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

587

588

1025

return 0;

589

1026

}

590

1027

592

1029

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

593

1030

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

594

1031

1032

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

1033

__attribute__((nonnull, warn_unused_result))

1034

static bool add_delete_local_route(const bool add,

1035

const char *address,

1036

AvahiIfIndex if_index){

1037

int ret;

1038

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

1039

char add_arg[] = "add";

1040

char delete_arg[] = "delete";

1041

char debug_flag[] = "--debug";

1042

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1043

if(pluginhelperdir == NULL){

1044

if(debug){

1045

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1046

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

1047

}

1048

return false;

1049

}

1050

1051

char interface[IF_NAMESIZE];

1052

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

1053

perror_plus("if_indextoname");

1054

return false;

1055

}

1056

1057

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

1058

if(devnull == -1){

1059

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

1060

return false;

1061

}

1062

pid_t pid = fork();

1063

if(pid == 0){

1064

/* Child */

1065

/* Raise privileges */

1066

errno = raise_privileges_permanently();

1067

if(errno != 0){

1068

perror_plus("Failed to raise privileges");

1069

/* _exit(EX_NOPERM); */

1070

} else {

1071

/* Set group */

1072

errno = 0;

1073

ret = setgid(0);

1074

if(ret == -1){

1075

perror_plus("setgid");

1076

close(devnull);

1077

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

close(devnull);

1085

_exit(EX_NOPERM);

1086

}

1087

}

1088

ret = dup2(devnull, STDIN_FILENO);

1089

if(ret == -1){

1090

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

1091

close(devnull);

1092

_exit(EX_OSERR);

1093

}

1094

ret = close(devnull);

1095

if(ret == -1){

1096

perror_plus("close");

1097

}

1098

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1099

if(ret == -1){

1100

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

1101

_exit(EX_OSERR);

1102

}

1103

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

1104

O_RDONLY

1105

| O_DIRECTORY

1106

| O_PATH

1107

| O_CLOEXEC));

1108

if(helperdir_fd == -1){

1109

perror_plus("open");

1110

_exit(EX_UNAVAILABLE);

1111

}

1112

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

1113

helper, O_RDONLY));

1114

if(helper_fd == -1){

1115

perror_plus("openat");

1116

close(helperdir_fd);

1117

_exit(EX_UNAVAILABLE);

1118

}

1119

close(helperdir_fd);

1120

#ifdef __GNUC__

1121

#pragma GCC diagnostic push

1122

#pragma GCC diagnostic ignored "-Wcast-qual"

1123

#endif

1124

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

1125

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

1126

interface, debug ? debug_flag : NULL, NULL },

1127

environ) == -1){

1128

#ifdef __GNUC__

1129

#pragma GCC diagnostic pop

1130

#endif

1131

perror_plus("fexecve");

1132

_exit(EXIT_FAILURE);

1133

}

1134

}

1135

if(pid == -1){

1136

perror_plus("fork");

1137

close(devnull);

1138

return false;

1139

}

1140

ret = close(devnull);

1141

if(ret == -1){

1142

perror_plus("close");

1143

}

1144

int status;

1145

pid_t pret = -1;

1146

errno = 0;

1147

do {

1148

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

1149

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

1150

int errno_raising = 0;

1151

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

1152

errno_raising = errno;

1153

perror_plus("Failed to raise privileges in order to"

1154

" kill helper program");

1155

}

1156

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

1157

perror_plus("kill");

1158

}

1159

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

1160

perror_plus("Failed to lower privileges after killing"

1161

" helper program");

1162

}

1163

return false;

1164

}

1165

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

1166

if(pret == -1){

1167

perror_plus("waitpid");

1168

return false;

1169

}

1170

if(WIFEXITED(status)){

1171

if(WEXITSTATUS(status) != 0){

1172

fprintf_plus(stderr, "Error: iprouteadddel exited"

1173

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

1174

return false;

1175

}

1176

return true;

1177

}

1178

if(WIFSIGNALED(status)){

1179

fprintf_plus(stderr, "Error: iprouteadddel died by"

1180

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

1181

return false;

1182

}

1183

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

1184

return false;

1185

}

1186

1187

__attribute__((nonnull, warn_unused_result))

1188

static bool add_local_route(const char *address,

1189

AvahiIfIndex if_index){

1190

if(debug){

1191

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

1192

}

1193

return add_delete_local_route(true, address, if_index);

1194

}

1195

1196

__attribute__((nonnull, warn_unused_result))

1197

static bool delete_local_route(const char *address,

1198

AvahiIfIndex if_index){

1199

if(debug){

1200

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

1201

}

1202

return add_delete_local_route(false, address, if_index);

1203

}

1204

595

1205

/* Called when a Mandos server is found */

596

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

1206

__attribute__((nonnull, warn_unused_result))

1207

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

597

1208

AvahiIfIndex if_index,

598

int af){

1209

int af, mandos_context *mc){

599

1210

int ret, tcp_sd = -1;

600

1211

ssize_t sret;

601

union {

602

struct sockaddr_in in;

603

struct sockaddr_in6 in6;

604

} to;

1212

struct sockaddr_storage to;

605

1213

char *buffer = NULL;

606

1214

char *decrypted_buffer = NULL;

607

1215

size_t buffer_length = 0;

610

1218

int retval = -1;

611

1219

gnutls_session_t session;

612

1220

int pf; /* Protocol family */

1221

bool route_added = false;

613

1222

614

1223

errno = 0;

615

1224

626

1235

pf = PF_INET;

627

1236

break;

628

1237

default:

629

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

1238

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

630

1239

errno = EINVAL;

631

1240

return -1;

632

1241

}

633

1242

634

ret = init_gnutls_session(&session);

1243

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

1244

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

1245

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

1246

bool match = false;

1247

{

1248

char *interface = NULL;

1249

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

1250

mc->interfaces_size,

1251

interface))){

1252

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

1253

match = true;

1254

break;

1255

}

1256

}

1257

}

1258

if(not match){

1259

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

1260

connect to the server */

1261

if(debug){

1262

char interface[IF_NAMESIZE];

1263

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

1264

perror_plus("if_indextoname");

1265

} else {

1266

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

1267

" \"%s\"\n",

1268

if_indextoname((unsigned int)if_index,

1269

interface));

1270

}

1271

}

1272

return -1;

1273

}

1274

}

1275

1276

ret = init_gnutls_session(&session, mc);

635

1277

if(ret != 0){

636

1278

return -1;

637

1279

}

638

1280

639

1281

if(debug){

640

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

641

"\n", ip, port);

1282

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

1283

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

642

1284

}

643

1285

644

tcp_sd = socket(pf, SOCK_STREAM, 0);

1286

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

645

1287

if(tcp_sd < 0){

646

1288

int e = errno;

647

1289

perror_plus("socket");

654

1296

goto mandos_end;

655

1297

}

656

1298

657

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

658

1299

if(af == AF_INET6){

659

to.in6.sin6_family = (sa_family_t)af;

660

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

1300

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

1301

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

1302

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

661

1303

} else { /* IPv4 */

662

to.in.sin_family = (sa_family_t)af;

663

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

1304

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

1305

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

1306

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

664

1307

}

665

1308

if(ret < 0 ){

666

1309

int e = errno;

670

1313

}

671

1314

if(ret == 0){

672

1315

int e = errno;

673

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

1316

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

674

1317

errno = e;

675

1318

goto mandos_end;

676

1319

}

677

1320

if(af == AF_INET6){

678

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

679

-Wconversion and

680

-Wunreachable-code */

681

682

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

683

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

684

-Wunreachable-code*/

1321

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

1322

if(IN6_IS_ADDR_LINKLOCAL

1323

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

685

1324

if(if_index == AVAHI_IF_UNSPEC){

686

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

687

" without a network interface\n");

1325

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

1326

" incomplete without a network interface\n");

688

1327

errno = EINVAL;

689

1328

goto mandos_end;

690

1329

}

691

1330

/* Set the network interface number as scope */

692

to.in6.sin6_scope_id = (uint32_t)if_index;

1331

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

693

1332

}

694

1333

} else {

695

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

696

-Wconversion and

697

-Wunreachable-code */

1334

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

698

1335

}

699

1336

700

1337

if(quit_now){

708

1345

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

709

1346

perror_plus("if_indextoname");

710

1347

} else {

711

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

712

ip, interface, port);

1348

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

1349

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

713

1350

}

714

1351

} else {

715

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

716

port);

1352

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

1353

ip, (uintmax_t)port);

717

1354

}

718

1355

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

719

1356

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

720

const char *pcret;

721

if(af == AF_INET6){

722

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

723

sizeof(addrstr));

724

} else {

725

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

726

sizeof(addrstr));

727

}

728

if(pcret == NULL){

729

perror_plus("inet_ntop");

730

} else {

731

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

732

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

733

}

734

}

735

}

736

737

if(quit_now){

738

errno = EINTR;

739

goto mandos_end;

740

}

741

742

if(af == AF_INET6){

743

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

744

} else {

745

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

746

}

747

if(ret < 0){

748

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

749

int e = errno;

750

perror_plus("connect");

751

errno = e;

752

}

753

goto mandos_end;

754

}

755

756

if(quit_now){

757

errno = EINTR;

758

goto mandos_end;

1357

if(af == AF_INET6){

1358

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

1359

sizeof(struct sockaddr_in6),

1360

addrstr, sizeof(addrstr), NULL, 0,

1361

NI_NUMERICHOST);

1362

} else {

1363

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

1364

sizeof(struct sockaddr_in),

1365

addrstr, sizeof(addrstr), NULL, 0,

1366

NI_NUMERICHOST);

1367

}

1368

if(ret == EAI_SYSTEM){

1369

perror_plus("getnameinfo");

1370

} else if(ret != 0) {

1371

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

1372

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

1373

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

1374

}

1375

}

1376

1377

if(quit_now){

1378

errno = EINTR;

1379

goto mandos_end;

1380

}

1381

1382

while(true){

1383

if(af == AF_INET6){

1384

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

1385

sizeof(struct sockaddr_in6));

1386

} else {

1387

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

1388

sizeof(struct sockaddr_in));

1389

}

1390

if(ret < 0){

1391

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

1392

and if_index != AVAHI_IF_UNSPEC

1393

and connect_to == NULL

1394

and not route_added and

1395

((af == AF_INET6 and not

1396

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1397

&to)->sin6_addr)))

1398

or (af == AF_INET and

1399

/* Not a a IPv4LL address */

1400

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

1401

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

1402

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

1403

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

1404

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

1405

connect to a Mandos server announced by Avahi on a server

1406

host with a global address. Work around this by retrying

1407

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

1408

1409

Avahi bug reference:

1410

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

1411

https://bugs.debian.org/587961

1412

*/

1413

if(debug){

1414

fprintf_plus(stderr, "Mandos server unreachable, trying"

1415

" direct route\n");

1416

}

1417

int e = errno;

1418

route_added = add_local_route(ip, if_index);

1419

if(route_added){

1420

continue;

1421

}

1422

errno = e;

1423

}

1424

if(errno != ECONNREFUSED or debug){

1425

int e = errno;

1426

perror_plus("connect");

1427

errno = e;

1428

}

1429

goto mandos_end;

1430

}

1431

1432

if(quit_now){

1433

errno = EINTR;

1434

goto mandos_end;

1435

}

1436

break;

759

1437

}

760

1438

761

1439

const char *out = mandos_protocol_version;

763

1441

while(true){

764

1442

size_t out_size = strlen(out);

765

1443

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

766

out_size - written));

1444

out_size - written));

767

1445

if(ret == -1){

768

1446

int e = errno;

769

1447

perror_plus("write");

789

1467

}

790

1468

791

1469

if(debug){

792

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

1470

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

793

1471

}

794

1472

795

1473

if(quit_now){

796

1474

errno = EINTR;

797

1475

goto mandos_end;

798

1476

}

799

800

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

801

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1477

1478

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

1479

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

1480

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

1481

gnutls_transport_set_ptr(session,

1482

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

802

1483

803

1484

if(quit_now){

804

1485

errno = EINTR;

815

1496

816

1497

if(ret != GNUTLS_E_SUCCESS){

817

1498

if(debug){

818

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

1499

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

819

1500

gnutls_perror(ret);

820

1501

}

821

1502

errno = EPROTO;

825

1506

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

826

1507

827

1508

if(debug){

828

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

829

ip);

1509

fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"

1510

" %s\n", ip);

830

1511

}

831

1512

832

1513

while(true){

837

1518

}

838

1519

839

1520

buffer_capacity = incbuffer(&buffer, buffer_length,

840

buffer_capacity);

1521

buffer_capacity);

841

1522

if(buffer_capacity == 0){

842

1523

int e = errno;

843

1524

perror_plus("incbuffer");

870

1551

}

871

1552

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

872

1553

if(ret < 0){

873

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

1554

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

1555

"***\n");

874

1556

gnutls_perror(ret);

875

1557

errno = EPROTO;

876

1558

goto mandos_end;

877

1559

}

878

1560

break;

879

1561

default:

880

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

881

" encrypted session with Mandos server\n");

1562

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

1563

" encrypted session with Mandos server\n");

882

1564

gnutls_bye(session, GNUTLS_SHUT_RDWR);

883

1565

errno = EIO;

884

1566

goto mandos_end;

889

1571

}

890

1572

891

1573

if(debug){

892

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

1574

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

893

1575

}

894

1576

895

1577

if(quit_now){

907

1589

908

1590

if(buffer_length > 0){

909

1591

ssize_t decrypted_buffer_size;

910

decrypted_buffer_size = pgp_packet_decrypt(buffer,

911

buffer_length,

912

&decrypted_buffer);

1592

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1593

&decrypted_buffer, mc);

913

1594

if(decrypted_buffer_size >= 0){

914

1595

1596

clearerr(stdout);

915

1597

written = 0;

916

1598

while(written < (size_t) decrypted_buffer_size){

917

1599

if(quit_now){

925

1607

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

926

1608

int e = errno;

927

1609

if(debug){

928

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

929

strerror(errno));

1610

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

1611

strerror(errno));

930

1612

}

931

1613

errno = e;

932

1614

goto mandos_end;

933

1615

}

934

1616

written += (size_t)ret;

935

1617

}

1618

ret = fflush(stdout);

1619

if(ret != 0){

1620

int e = errno;

1621

if(debug){

1622

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

1623

strerror(errno));

1624

}

1625

errno = e;

1626

goto mandos_end;

1627

}

936

1628

retval = 0;

937

1629

}

938

1630

}

941

1633

942

1634

mandos_end:

943

1635

{

1636

if(route_added){

1637

if(not delete_local_route(ip, if_index)){

1638

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

1639

" interface %d", ip, if_index);

1640

}

1641

}

944

1642

int e = errno;

945

1643

free(decrypted_buffer);

946

1644

free(buffer);

947

1645

if(tcp_sd >= 0){

948

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

1646

ret = close(tcp_sd);

949

1647

}

950

1648

if(ret == -1){

951

1649

if(e == 0){

976

1674

AVAHI_GCC_UNUSED AvahiStringList *txt,

977

1675

AVAHI_GCC_UNUSED AvahiLookupResultFlags

978

1676

flags,

979

AVAHI_GCC_UNUSED void* userdata){

980

assert(r);

1677

void *mc){

1678

if(r == NULL){

1679

return;

1680

}

981

1681

982

1682

/* Called whenever a service has been resolved successfully or

983

1683

timed out */

984

1684

985

1685

if(quit_now){

1686

avahi_s_service_resolver_free(r);

986

1687

return;

987

1688

}

988

1689

989

1690

switch(event){

990

1691

default:

991

1692

case AVAHI_RESOLVER_FAILURE:

992

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

993

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

994

avahi_strerror(avahi_server_errno(mc.server)));

1693

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

1694

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

1695

domain,

1696

avahi_strerror(avahi_server_errno

1697

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

995

1698

break;

996

1699

997

1700

case AVAHI_RESOLVER_FOUND:

999

1702

char ip[AVAHI_ADDRESS_STR_MAX];

1000

1703

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

1001

1704

if(debug){

1002

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

1003

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

1004

ip, (intmax_t)interface, port);

1705

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

1706

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

1707

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

1005

1708

}

1006

int ret = start_mandos_communication(ip, port, interface,

1007

avahi_proto_to_af(proto));

1709

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

1710

interface,

1711

avahi_proto_to_af(proto),

1712

mc);

1008

1713

if(ret == 0){

1009

avahi_simple_poll_quit(mc.simple_poll);

1714

avahi_simple_poll_quit(simple_poll);

1010

1715

} else {

1011

ret = add_server(ip, port, interface,

1012

avahi_proto_to_af(proto));

1716

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

1717

avahi_proto_to_af(proto),

1718

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

1719

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

1720

" list\n", name);

1721

}

1013

1722

}

1014

1723

}

1015

1724

}

1025

1734

const char *domain,

1026

1735

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1027

1736

flags,

1028

AVAHI_GCC_UNUSED void* userdata){

1029

assert(b);

1737

void *mc){

1738

if(b == NULL){

1739

return;

1740

}

1030

1741

1031

1742

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

1032

1743

is removed from the LAN */

1039

1750

default:

1040

1751

case AVAHI_BROWSER_FAILURE:

1041

1752

1042

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

1043

avahi_strerror(avahi_server_errno(mc.server)));

1044

avahi_simple_poll_quit(mc.simple_poll);

1753

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

1754

avahi_strerror(avahi_server_errno

1755

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

1756

avahi_simple_poll_quit(simple_poll);

1045

1757

return;

1046

1758

1047

1759

case AVAHI_BROWSER_NEW:

1050

1762

the callback function is called the Avahi server will free the

1051

1763

resolver for us. */

1052

1764

1053

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

1054

name, type, domain, protocol, 0,

1055

resolve_callback, NULL) == NULL)

1056

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

1057

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

1765

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

1766

interface, protocol, name, type,

1767

domain, protocol, 0,

1768

resolve_callback, mc) == NULL)

1769

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

1770

" %s\n", name,

1771

avahi_strerror(avahi_server_errno

1772

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

1058

1773

break;

1059

1774

1060

1775

case AVAHI_BROWSER_REMOVE:

1063

1778

case AVAHI_BROWSER_ALL_FOR_NOW:

1064

1779

case AVAHI_BROWSER_CACHE_EXHAUSTED:

1065

1780

if(debug){

1066

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

1781

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

1782

" searching...\n");

1067

1783

}

1068

1784

break;

1069

1785

}

1070

1786

}

1071

1787

1072

/* Signal handler that stops main loop after sigterm has been called */

1788

/* Signal handler that stops main loop after SIGTERM */

1073

1789

static void handle_sigterm(int sig){

1074

1790

if(quit_now){

1075

1791

return;

1078

1794

signal_received = sig;

1079

1795

int old_errno = errno;

1080

1796

/* set main loop to exit */

1081

if(mc.simple_poll != NULL){

1082

avahi_simple_poll_quit(mc.simple_poll);

1797

if(simple_poll != NULL){

1798

avahi_simple_poll_quit(simple_poll);

1083

1799

}

1084

1800

errno = old_errno;

1085

1801

}

1086

1802

1803

__attribute__((nonnull, warn_unused_result))

1804

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

1805

int ret;

1806

int old_errno;

1807

1808

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

1809

if(s < 0){

1810

old_errno = errno;

1811

perror_plus("socket");

1812

errno = old_errno;

1813

return false;

1814

}

1815

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

1816

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

1817

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1818

if(ret == -1){

1819

if(debug){

1820

old_errno = errno;

1821

perror_plus("ioctl SIOCGIFFLAGS");

1822

errno = old_errno;

1823

}

1824

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

1825

old_errno = errno;

1826

perror_plus("close");

1827

errno = old_errno;

1828

}

1829

return false;

1830

}

1831

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

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1836

return true;

1837

}

1838

1839

__attribute__((nonnull, warn_unused_result))

1840

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

1841

1842

/* Reject the loopback device */

1843

if(ifr->ifr_flags & IFF_LOOPBACK){

1844

if(debug){

1845

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

1846

ifname);

1847

}

1848

return false;

1849

}

1850

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

1851

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

1852

if(debug){

1853

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

1854

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

1855

}

1856

return true;

1857

}

1858

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

1859

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

1860

if(debug){

1861

fprintf_plus(stderr, "Rejecting non-broadcast interface"

1862

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

1863

}

1864

return false;

1865

}

1866

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

1867

if(ifr->ifr_flags & IFF_NOARP){

1868

if(debug){

1869

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

1870

ifname);

1871

}

1872

return false;

1873

}

1874

1875

/* Accept this device */

1876

if(debug){

1877

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

1878

}

1879

return true;

1880

}

1881

1087

1882

/*

1088

1883

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

1089

1884

* corresponds to an acceptable network device.

1090

1885

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

1091

1886

*/

1887

__attribute__((nonnull, warn_unused_result))

1092

1888

int good_interface(const struct dirent *if_entry){

1093

ssize_t ssret;

1094

char *flagname = NULL;

1095

1889

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

1096

1890

return 0;

1097

1891

}

1098

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

1099

if_entry->d_name);

1100

if(ret < 0){

1101

perror_plus("asprintf");

1102

return 0;

1103

}

1104

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

1105

if(flags_fd == -1){

1106

perror_plus("open");

1107

free(flagname);

1108

return 0;

1109

}

1110

free(flagname);

1111

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

1112

/* read line from flags_fd */

1113

ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */

1114

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

1115

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

1116

if(flagstring == NULL){

1117

perror_plus("malloc");

1118

close(flags_fd);

1119

return 0;

1120

}

1121

while(to_read > 0){

1122

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

1123

(size_t)to_read));

1124

if(ssret == -1){

1125

perror_plus("read");

1126

free(flagstring);

1127

close(flags_fd);

1128

return 0;

1129

}

1130

to_read -= ssret;

1131

if(ssret == 0){

1132

break;

1133

}

1134

}

1135

close(flags_fd);

1136

intmax_t tmpmax;

1137

char *tmp;

1138

errno = 0;

1139

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

1140

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

1141

and not (isspace(*tmp)))

1142

or tmpmax != (ifreq_flags)tmpmax){

1143

if(debug){

1144

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

1145

flagstring, if_entry->d_name);

1146

}

1147

free(flagstring);

1148

return 0;

1149

}

1150

free(flagstring);

1151

ifreq_flags flags = (ifreq_flags)tmpmax;

1152

/* Reject the loopback device */

1153

if(flags & IFF_LOOPBACK){

1154

if(debug){

1155

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

1156

if_entry->d_name);

1157

}

1158

return 0;

1159

}

1160

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

1161

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

1162

if(debug){

1163

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

1164

if_entry->d_name);

1165

}

1166

return 1;

1167

}

1168

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

1169

if(not (flags & IFF_BROADCAST)){

1170

if(debug){

1171

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

1172

if_entry->d_name);

1173

}

1174

return 0;

1175

}

1176

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

1177

if(flags & IFF_NOARP){

1178

if(debug){

1179

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

1180

if_entry->d_name);

1181

}

1182

return 0;

1183

}

1184

/* Accept this device */

1185

if(debug){

1186

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

1187

if_entry->d_name);

1892

1893

struct ifreq ifr;

1894

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

1895

if(debug){

1896

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

1897

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

1898

}

1899

return 0;

1900

}

1901

1902

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

1903

return 0;

1188

1904

}

1189

1905

return 1;

1190

1906

}

1191

1907

1908

/*

1909

* This function determines if a network interface is up.

1910

*/

1911

__attribute__((nonnull, warn_unused_result))

1912

bool interface_is_up(const char *interface){

1913

struct ifreq ifr;

1914

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

1915

if(debug){

1916

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

1917

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

1918

}

1919

return false;

1920

}

1921

1922

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

1923

}

1924

1925

/*

1926

* This function determines if a network interface is running

1927

*/

1928

__attribute__((nonnull, warn_unused_result))

1929

bool interface_is_running(const char *interface){

1930

struct ifreq ifr;

1931

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

1932

if(debug){

1933

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

1934

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

1935

}

1936

return false;

1937

}

1938

1939

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

1940

}

1941

1942

__attribute__((nonnull, pure, warn_unused_result))

1192

1943

int notdotentries(const struct dirent *direntry){

1193

1944

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

1194

1945

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

1200

1951

return 1;

1201

1952

}

1202

1953

1203

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

1954

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

1955

__attribute__((nonnull, warn_unused_result))

1956

int runnable_hook(const struct dirent *direntry){

1957

int ret;

1958

size_t sret;

1959

struct stat st;

1960

1961

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

1962

/* Empty name? */

1963

return 0;

1964

}

1965

1966

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

1967

"abcdefghijklmnopqrstuvwxyz"

1968

"0123456789"

1969

"_.-");

1970

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

1971

/* Contains non-allowed characters */

1972

if(debug){

1973

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

1974

direntry->d_name);

1975

}

1976

return 0;

1977

}

1978

1979

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

1980

if(ret == -1){

1981

if(debug){

1982

perror_plus("Could not stat hook");

1983

}

1984

return 0;

1985

}

1986

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

1987

/* Not a regular file */

1988

if(debug){

1989

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

1990

direntry->d_name);

1991

}

1992

return 0;

1993

}

1994

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

1995

/* Not executable */

1996

if(debug){

1997

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

1998

direntry->d_name);

1999

}

2000

return 0;

2001

}

2002

if(debug){

2003

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

2004

direntry->d_name);

2005

}

2006

return 1;

2007

}

2008

2009

__attribute__((nonnull, warn_unused_result))

2010

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2011

mandos_context *mc){

1204

2012

int ret;

1205

2013

struct timespec now;

1206

2014

struct timespec waited_time;

1207

2015

intmax_t block_time;

1208

2016

1209

2017

while(true){

1210

if(mc.current_server == NULL){

1211

if (debug){

1212

fprintf(stderr, "Wait until first server is found. No timeout!\n");

2018

if(mc->current_server == NULL){

2019

if(debug){

2020

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

2021

" No timeout!\n");

1213

2022

}

1214

2023

ret = avahi_simple_poll_iterate(s, -1);

1215

2024

} else {

1216

if (debug){

1217

fprintf(stderr, "Check current_server if we should run it, or wait\n");

2025

if(debug){

2026

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

2027

" it, or wait\n");

1218

2028

}

1219

2029

/* the current time */

1220

2030

ret = clock_gettime(CLOCK_MONOTONIC, &now);

1224

2034

}

1225

2035

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

1226

2036

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

1227

waited_time.tv_sec = now.tv_sec - mc.current_server->last_seen.tv_sec;

1228

waited_time.tv_nsec = now.tv_nsec - mc.current_server->last_seen.tv_nsec;

1229

/* total time is 10s/10000ms. Converting to s to ms by 1000/s, and ns to ms by divind by 1000000. */

1230

block_time = (retry_interval - ((intmax_t)waited_time.tv_sec * 1000)) - ((intmax_t)waited_time.tv_nsec / 1000000);

1231

1232

if (debug){

1233

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

2037

waited_time.tv_sec = (now.tv_sec

2038

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

2039

waited_time.tv_nsec = (now.tv_nsec

2040

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

2041

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

2042

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

2043

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

2044

block_time = ((retry_interval

2045

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

2046

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

2047

2048

if(debug){

2049

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

2050

block_time);

1234

2051

}

1235

2052

1236

2053

if(block_time <= 0){

1237

ret = start_mandos_communication(mc.current_server->ip,

1238

mc.current_server->port,

1239

mc.current_server->if_index,

1240

mc.current_server->af);

2054

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

2055

mc->current_server->port,

2056

mc->current_server->if_index,

2057

mc->current_server->af, mc);

1241

2058

if(ret == 0){

1242

avahi_simple_poll_quit(mc.simple_poll);

2059

avahi_simple_poll_quit(s);

1243

2060

return 0;

1244

2061

}

1245

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

2062

ret = clock_gettime(CLOCK_MONOTONIC,

2063

&mc->current_server->last_seen);

1246

2064

if(ret == -1){

1247

2065

perror_plus("clock_gettime");

1248

2066

return -1;

1249

2067

}

1250

mc.current_server = mc.current_server->next;

1251

block_time = 0; /* call avahi to find new mandos servers, but dont block */

2068

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

2069

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

2070

servers, but don't block */

1252

2071

}

1253

2072

1254

2073

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

1255

2074

}

1256

2075

if(ret != 0){

1257

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

2076

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

1258

2077

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

1259

2078

}

1260

2079

}

1261

2080

}

1262

2081

}

1263

2082

2083

__attribute__((nonnull))

2084

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

2085

const float delay){

2086

struct dirent **direntries = NULL;

2087

if(hookdir_fd == -1){

2088

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2089

| O_CLOEXEC);

2090

if(hookdir_fd == -1){

2091

if(errno == ENOENT){

2092

if(debug){

2093

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

2094

" found\n", hookdir);

2095

}

2096

} else {

2097

perror_plus("open");

2098

}

2099

return;

2100

}

2101

}

2102

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

2103

if(devnull == -1){

2104

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

2105

return;

2106

}

2107

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

2108

runnable_hook, alphasort);

2109

if(numhooks == -1){

2110

perror_plus("scandir");

2111

close(devnull);

2112

return;

2113

}

2114

struct dirent *direntry;

2115

int ret;

2116

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

2117

direntry = direntries[i];

2118

if(debug){

2119

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

2120

direntry->d_name);

2121

}

2122

pid_t hook_pid = fork();

2123

if(hook_pid == 0){

2124

/* Child */

2125

/* Raise privileges */

2126

errno = raise_privileges_permanently();

2127

if(errno != 0){

2128

perror_plus("Failed to raise privileges");

2129

_exit(EX_NOPERM);

2130

}

2131

/* Set group */

2132

errno = 0;

2133

ret = setgid(0);

2134

if(ret == -1){

2135

perror_plus("setgid");

2136

_exit(EX_NOPERM);

2137

}

2138

/* Reset supplementary groups */

2139

errno = 0;

2140

ret = setgroups(0, NULL);

2141

if(ret == -1){

2142

perror_plus("setgroups");

2143

_exit(EX_NOPERM);

2144

}

2145

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

2146

if(ret == -1){

2147

perror_plus("setenv");

2148

_exit(EX_OSERR);

2149

}

2150

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

2151

if(ret == -1){

2152

perror_plus("setenv");

2153

_exit(EX_OSERR);

2154

}

2155

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

2156

if(ret == -1){

2157

perror_plus("setenv");

2158

_exit(EX_OSERR);

2159

}

2160

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

2161

if(ret == -1){

2162

perror_plus("setenv");

2163

_exit(EX_OSERR);

2164

}

2165

char *delaystring;

2166

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

2167

if(ret == -1){

2168

perror_plus("asprintf");

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

if(ret == -1){

2173

free(delaystring);

2174

perror_plus("setenv");

2175

_exit(EX_OSERR);

2176

}

2177

free(delaystring);

2178

if(connect_to != NULL){

2179

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

2180

if(ret == -1){

2181

perror_plus("setenv");

2182

_exit(EX_OSERR);

2183

}

2184

}

2185

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

2186

direntry->d_name,

2187

O_RDONLY));

2188

if(hook_fd == -1){

2189

perror_plus("openat");

2190

_exit(EXIT_FAILURE);

2191

}

2192

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

2193

perror_plus("close");

2194

_exit(EXIT_FAILURE);

2195

}

2196

ret = dup2(devnull, STDIN_FILENO);

2197

if(ret == -1){

2198

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

2199

_exit(EX_OSERR);

2200

}

2201

ret = close(devnull);

2202

if(ret == -1){

2203

perror_plus("close");

2204

_exit(EX_OSERR);

2205

}

2206

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2207

if(ret == -1){

2208

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

2209

_exit(EX_OSERR);

2210

}

2211

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

2212

environ) == -1){

2213

perror_plus("fexecve");

2214

_exit(EXIT_FAILURE);

2215

}

2216

} else {

2217

if(hook_pid == -1){

2218

perror_plus("fork");

2219

free(direntry);

2220

continue;

2221

}

2222

int status;

2223

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

2224

perror_plus("waitpid");

2225

free(direntry);

2226

continue;

2227

}

2228

if(WIFEXITED(status)){

2229

if(WEXITSTATUS(status) != 0){

2230

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

2231

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

2232

WEXITSTATUS(status));

2233

free(direntry);

2234

continue;

2235

}

2236

} else if(WIFSIGNALED(status)){

2237

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

2238

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

2239

WTERMSIG(status));

2240

free(direntry);

2241

continue;

2242

} else {

2243

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

2244

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

2245

free(direntry);

2246

continue;

2247

}

2248

}

2249

if(debug){

2250

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

2251

direntry->d_name);

2252

}

2253

free(direntry);

2254

}

2255

free(direntries);

2256

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

2257

perror_plus("close");

2258

} else {

2259

hookdir_fd = -1;

2260

}

2261

close(devnull);

2262

}

2263

2264

__attribute__((nonnull, warn_unused_result))

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

2268

int ret;

2269

struct ifreq network;

2270

unsigned int if_index = if_nametoindex(interface);

2271

if(if_index == 0){

2272

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

2273

errno = old_errno;

2274

return ENXIO;

2275

}

2276

2277

if(quit_now){

2278

errno = old_errno;

2279

return EINTR;

2280

}

2281

2282

if(not interface_is_up(interface)){

2283

int ret_errno = 0;

2284

int ioctl_errno = 0;

2285

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

2286

ret_errno = errno;

2287

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

2288

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

2289

errno = old_errno;

2290

return ret_errno;

2291

}

2292

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

2293

2294

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

2295

if(sd == -1){

2296

ret_errno = errno;

2297

perror_plus("socket");

2298

errno = old_errno;

2299

return ret_errno;

2300

}

2301

2302

if(quit_now){

2303

ret = close(sd);

2304

if(ret == -1){

2305

perror_plus("close");

2306

}

2307

errno = old_errno;

2308

return EINTR;

2309

}

2310

2311

if(debug){

2312

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

2313

interface);

2314

}

2315

2316

/* Raise privileges */

2317

ret_errno = raise_privileges();

2318

if(ret_errno != 0){

2319

errno = ret_errno;

2320

perror_plus("Failed to raise privileges");

2321

}

2322

2323

#ifdef __linux__

2324

int ret_linux;

2325

bool restore_loglevel = false;

2326

if(ret_errno == 0){

2327

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2328

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

2329

ret_linux = klogctl(8, NULL, 5);

2330

if(ret_linux == -1){

2331

perror_plus("klogctl");

2332

} else {

2333

restore_loglevel = true;

2334

}

2335

}

2336

#endif /* __linux__ */

2337

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

2338

ioctl_errno = errno;

2339

#ifdef __linux__

2340

if(restore_loglevel){

2341

ret_linux = klogctl(7, NULL, 0);

2342

if(ret_linux == -1){

2343

perror_plus("klogctl");

2344

}

2345

}

2346

#endif /* __linux__ */

2347

2348

/* If raise_privileges() succeeded above */

2349

if(ret_errno == 0){

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

2357

2358

/* Close the socket */

2359

ret = close(sd);

2360

if(ret == -1){

2361

perror_plus("close");

2362

}

2363

2364

if(ret_setflags == -1){

2365

errno = ioctl_errno;

2366

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2367

errno = old_errno;

2368

return ioctl_errno;

2369

}

2370

} else if(debug){

2371

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

2372

interface);

2373

}

2374

2375

/* Sleep checking until interface is running.

2376

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

2377

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

2378

if(interface_is_running(interface)){

2379

break;

2380

}

2381

struct timespec sleeptime = { .tv_nsec = 250000000 };

2382

ret = nanosleep(&sleeptime, NULL);

2383

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

2384

perror_plus("nanosleep");

2385

}

2386

}

2387

2388

errno = old_errno;

2389

return 0;

2390

}

2391

2392

__attribute__((nonnull, warn_unused_result))

2393

int take_down_interface(const char *const interface){

2394

int old_errno = errno;

2395

struct ifreq network;

2396

unsigned int if_index = if_nametoindex(interface);

2397

if(if_index == 0){

2398

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

2399

errno = old_errno;

2400

return ENXIO;

2401

}

2402

if(interface_is_up(interface)){

2403

int ret_errno = 0;

2404

int ioctl_errno = 0;

2405

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

2406

ret_errno = errno;

2407

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

2408

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

2409

errno = old_errno;

2410

return ret_errno;

2411

}

2412

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

2413

2414

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

2415

if(sd == -1){

2416

ret_errno = errno;

2417

perror_plus("socket");

2418

errno = old_errno;

2419

return ret_errno;

2420

}

2421

2422

if(debug){

2423

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

2424

interface);

2425

}

2426

2427

/* Raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

}

2433

2434

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

2435

ioctl_errno = errno;

2436

2437

/* If raise_privileges() succeeded above */

2438

if(ret_errno == 0){

2439

/* Lower privileges */

2440

ret_errno = lower_privileges();

2441

if(ret_errno != 0){

2442

errno = ret_errno;

2443

perror_plus("Failed to lower privileges");

2444

}

2445

}

2446

2447

/* Close the socket */

2448

int ret = close(sd);

2449

if(ret == -1){

2450

perror_plus("close");

2451

}

2452

2453

if(ret_setflags == -1){

2454

errno = ioctl_errno;

2455

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2456

errno = old_errno;

2457

return ioctl_errno;

2458

}

2459

} else if(debug){

2460

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

2461

interface);

2462

}

2463

2464

errno = old_errno;

2465

return 0;

2466

}

2467

1264

2468

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

2469

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

2470

#if GNUTLS_VERSION_NUMBER >= 0x030606

2471

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

2472

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

2473

":%PROFILE_ULTRA",

2474

#elif GNUTLS_VERSION_NUMBER < 0x030600

2475

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

2476

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

2477

#else

2478

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

2479

#endif

2480

.current_server = NULL, .interfaces = NULL,

2481

.interfaces_size = 0 };

1265

2482

AvahiSServiceBrowser *sb = NULL;

1266

int error;

2483

error_t ret_errno;

1267

2484

int ret;

1268

2485

intmax_t tmpmax;

1269

2486

char *tmp;

1270

2487

int exitcode = EXIT_SUCCESS;

1271

const char *interface = "";

1272

struct ifreq network;

1273

int sd = -1;

1274

bool take_down_interface = false;

1275

uid_t uid;

1276

gid_t gid;

1277

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

1278

bool tempdir_created = false;

2488

char *interfaces_to_take_down = NULL;

2489

size_t interfaces_to_take_down_size = 0;

2490

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

2491

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

2492

char *tempdir = NULL;

1279

2493

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1280

2494

const char *seckey = PATHDIR "/" SECKEY;

1281

2495

const char *pubkey = PATHDIR "/" PUBKEY;

2496

#if GNUTLS_VERSION_NUMBER >= 0x030606

2497

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2498

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2499

#endif

2500

const char *dh_params_file = NULL;

2501

char *interfaces_hooks = NULL;

1282

2502

1283

2503

bool gnutls_initialized = false;

1284

2504

bool gpgme_initialized = false;

1285

2505

float delay = 2.5f;

1286

double retry_interval = 10; /* 10s between retrying a server and checking again*/

2506

double retry_interval = 10; /* 10s between trying a server and

2507

retrying the same server again */

1287

2508

1288

2509

struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };

1289

2510

struct sigaction sigterm_action = { .sa_handler = handle_sigterm };

1329

2550

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

1330

2551

.arg = "FILE",

1331

2552

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

1332

.group = 2 },

2553

.group = 1 },

2554

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

2555

.arg = "FILE",

2556

#if GNUTLS_VERSION_NUMBER >= 0x030606

2557

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

2558

#else

2559

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

2560

#endif

2561

.group = 1 },

2562

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

2563

.arg = "FILE",

2564

#if GNUTLS_VERSION_NUMBER >= 0x030606

2565

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

2566

#else

2567

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

2568

#endif

2569

.group = 1 },

1333

2570

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

1334

2571

.arg = "BITS",

1335

2572

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

1336

2573

" Diffie-Hellman key exchange",

1337

2574

.group = 2 },

2575

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

2576

.arg = "FILE",

2577

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

2578

" for the Diffie-Hellman key exchange",

2579

.group = 2 },

1338

2580

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

1339

2581

.arg = "STRING",

1340

2582

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

1345

2587

.group = 2 },

1346

2588

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

1347

2589

.arg = "SECONDS",

1348

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

2590

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

2591

.group = 2 },

2592

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

2593

.arg = "DIR",

2594

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

1349

2595

.group = 2 },

1350

2596

/*

1351

2597

* These reproduce what we would get without ARGP_NO_HELP

1370

2616

connect_to = arg;

1371

2617

break;

1372

2618

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

1373

interface = arg;

2619

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

2620

arg, (int)',');

2621

if(ret_errno != 0){

2622

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

2623

}

1374

2624

break;

1375

2625

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

1376

2626

seckey = arg;

1378

2628

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

1379

2629

pubkey = arg;

1380

2630

break;

2631

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

2632

#if GNUTLS_VERSION_NUMBER >= 0x030606

2633

tls_privkey = arg;

2634

#endif

2635

break;

2636

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

2637

#if GNUTLS_VERSION_NUMBER >= 0x030606

2638

tls_pubkey = arg;

2639

#endif

2640

break;

1381

2641

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

1382

2642

errno = 0;

1383

2643

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

1387

2647

}

1388

2648

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

1389

2649

break;

2650

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

2651

dh_params_file = arg;

2652

break;

1390

2653

case 130: /* --priority */

1391

2654

mc.priority = arg;

1392

2655

break;

1400

2663

errno = 0;

1401

2664

retry_interval = strtod(arg, &tmp);

1402

2665

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

1403

or (retry_interval * 1000) > INT_MAX){

2666

or (retry_interval * 1000) > INT_MAX

2667

or retry_interval < 0){

1404

2668

argp_error(state, "Bad retry interval");

1405

2669

}

1406

2670

break;

2671

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

2672

hookdir = arg;

2673

break;

1407

2674

/*

1408

2675

* These reproduce what we would get without ARGP_NO_HELP

1409

2676

*/

1411

2678

argp_state_help(state, state->out_stream,

1412

2679

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1413

2680

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

1414

2682

case -3: /* --usage */

1415

2683

argp_state_help(state, state->out_stream,

1416

2684

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

1417

2686

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

1418

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

2687

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

1419

2688

exit(argp_err_exit_status);

1420

2689

break;

1421

2690

default:

1428

2697

.args_doc = "",

1429

2698

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

1430

2699

" passwords from a Mandos server" };

1431

ret = argp_parse(&argp, argc, argv,

1432

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1433

switch(ret){

2700

ret_errno = argp_parse(&argp, argc, argv,

2701

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2702

switch(ret_errno){

1434

2703

case 0:

1435

2704

break;

1436

2705

case ENOMEM:

1437

2706

default:

1438

errno = ret;

2707

errno = ret_errno;

1439

2708

perror_plus("argp_parse");

1440

2709

exitcode = EX_OSERR;

1441

2710

goto end;

1445

2714

}

1446

2715

}

1447

2716

2717

{

2718

/* Work around Debian bug #633582:

2719

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

2720

2721

/* Re-raise privileges */

2722

ret = raise_privileges();

2723

if(ret != 0){

2724

errno = ret;

2725

perror_plus("Failed to raise privileges");

2726

} else {

2727

struct stat st;

2728

2729

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

2730

int seckey_fd = open(seckey, O_RDONLY);

2731

if(seckey_fd == -1){

2732

perror_plus("open");

2733

} else {

2734

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

2735

if(ret == -1){

2736

perror_plus("fstat");

2737

} else {

2738

if(S_ISREG(st.st_mode)

2739

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

2740

ret = fchown(seckey_fd, uid, gid);

2741

if(ret == -1){

2742

perror_plus("fchown");

2743

}

2744

}

2745

}

2746

close(seckey_fd);

2747

}

2748

}

2749

2750

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

2751

int pubkey_fd = open(pubkey, O_RDONLY);

2752

if(pubkey_fd == -1){

2753

perror_plus("open");

2754

} else {

2755

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

2756

if(ret == -1){

2757

perror_plus("fstat");

2758

} else {

2759

if(S_ISREG(st.st_mode)

2760

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

2761

ret = fchown(pubkey_fd, uid, gid);

2762

if(ret == -1){

2763

perror_plus("fchown");

2764

}

2765

}

2766

}

2767

close(pubkey_fd);

2768

}

2769

}

2770

2771

if(dh_params_file != NULL

2772

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

2773

int dhparams_fd = open(dh_params_file, O_RDONLY);

2774

if(dhparams_fd == -1){

2775

perror_plus("open");

2776

} else {

2777

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

2778

if(ret == -1){

2779

perror_plus("fstat");

2780

} else {

2781

if(S_ISREG(st.st_mode)

2782

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

2783

ret = fchown(dhparams_fd, uid, gid);

2784

if(ret == -1){

2785

perror_plus("fchown");

2786

}

2787

}

2788

}

2789

close(dhparams_fd);

2790

}

2791

}

2792

2793

/* Lower privileges */

2794

ret = lower_privileges();

2795

if(ret != 0){

2796

errno = ret;

2797

perror_plus("Failed to lower privileges");

2798

}

2799

}

2800

}

2801

2802

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

2803

{

2804

char *interface = NULL;

2805

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

2806

interface))){

2807

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

2808

and if_nametoindex(interface) == 0){

2809

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

2810

fprintf_plus(stderr, "Not using nonexisting interface"

2811

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

2812

}

2813

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

2814

interface = NULL;

2815

}

2816

}

2817

}

2818

2819

/* Run network hooks */

2820

{

2821

if(mc.interfaces != NULL){

2822

interfaces_hooks = malloc(mc.interfaces_size);

2823

if(interfaces_hooks == NULL){

2824

perror_plus("malloc");

2825

goto end;

2826

}

2827

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

2828

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

2829

}

2830

run_network_hooks("start", interfaces_hooks != NULL ?

2831

interfaces_hooks : "", delay);

2832

}

2833

1448

2834

if(not debug){

1449

2835

avahi_set_log_function(empty_log);

1450

2836

}

1451

1452

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

1453

struct dirent **direntries;

1454

ret = scandir(sys_class_net, &direntries, good_interface,

1455

alphasort);

1456

if(ret >= 1){

1457

/* Pick the first good interface */

1458

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

1459

if(debug){

1460

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

1461

}

1462

if(interface == NULL){

1463

perror_plus("malloc");

1464

free(direntries);

1465

exitcode = EXIT_FAILURE;

1466

goto end;

1467

}

1468

free(direntries);

1469

} else {

1470

free(direntries);

1471

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

1472

exitcode = EXIT_FAILURE;

1473

goto end;

1474

}

1475

}

1476

2837

1477

2838

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

1478

2839

from the signal handler */

1479

2840

/* Initialize the pseudo-RNG for Avahi */

1480

2841

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

1481

mc.simple_poll = avahi_simple_poll_new();

1482

if(mc.simple_poll == NULL){

1483

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

2842

simple_poll = avahi_simple_poll_new();

2843

if(simple_poll == NULL){

2844

fprintf_plus(stderr,

2845

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

1484

2846

exitcode = EX_UNAVAILABLE;

1485

2847

goto end;

1486

2848

}

1548

2910

}

1549

2911

}

1550

2912

1551

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

1552

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

1553

if_index = (AvahiIfIndex) if_nametoindex(interface);

1554

if(if_index == 0){

1555

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

1556

exitcode = EX_UNAVAILABLE;

1557

goto end;

1558

}

1559

1560

if(quit_now){

1561

goto end;

1562

}

1563

1564

/* Re-raise priviliges */

1565

errno = 0;

1566

ret = seteuid(0);

1567

if(ret == -1){

1568

perror_plus("seteuid");

1569

}

1570

1571

#ifdef __linux__

1572

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1573

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

1574

ret = klogctl(8, NULL, 5);

1575

bool restore_loglevel = true;

1576

if(ret == -1){

1577

restore_loglevel = false;

1578

perror_plus("klogctl");

1579

}

1580

#endif /* __linux__ */

1581

1582

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1583

if(sd < 0){

1584

perror_plus("socket");

1585

exitcode = EX_OSERR;

1586

#ifdef __linux__

1587

if(restore_loglevel){

1588

ret = klogctl(7, NULL, 0);

1589

if(ret == -1){

1590

perror_plus("klogctl");

1591

}

1592

}

1593

#endif /* __linux__ */

1594

/* Lower privileges */

1595

errno = 0;

1596

ret = seteuid(uid);

1597

if(ret == -1){

1598

perror_plus("seteuid");

1599

}

1600

goto end;

1601

}

1602

strcpy(network.ifr_name, interface);

1603

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

1604

if(ret == -1){

1605

perror_plus("ioctl SIOCGIFFLAGS");

1606

#ifdef __linux__

1607

if(restore_loglevel){

1608

ret = klogctl(7, NULL, 0);

1609

if(ret == -1){

1610

perror_plus("klogctl");

1611

}

1612

}

1613

#endif /* __linux__ */

1614

exitcode = EX_OSERR;

1615

/* Lower privileges */

1616

errno = 0;

1617

ret = seteuid(uid);

1618

if(ret == -1){

1619

perror_plus("seteuid");

1620

}

1621

goto end;

1622

}

1623

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

1624

network.ifr_flags |= IFF_UP;

1625

take_down_interface = true;

1626

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

1627

if(ret == -1){

1628

take_down_interface = false;

1629

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1630

exitcode = EX_OSERR;

1631

#ifdef __linux__

1632

if(restore_loglevel){

1633

ret = klogctl(7, NULL, 0);

1634

if(ret == -1){

1635

perror_plus("klogctl");

2913

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

2914

if(mc.interfaces == NULL){

2915

struct dirent **direntries = NULL;

2916

/* Look for any good interfaces */

2917

ret = scandir(sys_class_net, &direntries, good_interface,

2918

alphasort);

2919

if(ret >= 1){

2920

/* Add all found interfaces to interfaces list */

2921

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

2922

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

2923

direntries[i]->d_name);

2924

if(ret_errno != 0){

2925

errno = ret_errno;

2926

perror_plus("argz_add");

2927

free(direntries[i]);

2928

continue;

2929

}

2930

if(debug){

2931

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

2932

direntries[i]->d_name);

2933

}

2934

free(direntries[i]);

2935

}

2936

free(direntries);

2937

} else {

2938

if(ret == 0){

2939

free(direntries);

2940

}

2941

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

2942

exitcode = EXIT_FAILURE;

2943

goto end;

2944

}

2945

}

2946

2947

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

2948

{

2949

char *interface = NULL;

2950

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

2951

interface))){

2952

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

2953

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

2954

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

2955

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

2956

interface);

2957

interface = NULL;

2958

while((interface = argz_next(mc.interfaces,

2959

mc.interfaces_size, interface))){

2960

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

2961

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

2962

interface);

2963

interface = NULL;

1636

2964

}

1637

2965

}

1638

#endif /* __linux__ */

1639

/* Lower privileges */

1640

errno = 0;

1641

ret = seteuid(uid);

1642

if(ret == -1){

1643

perror_plus("seteuid");

1644

}

1645

goto end;

1646

}

1647

}

1648

/* sleep checking until interface is running. Check every 0.25s, up to total time of delay */

1649

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

1650

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

1651

if(ret == -1){

1652

perror_plus("ioctl SIOCGIFFLAGS");

1653

} else if(network.ifr_flags & IFF_RUNNING){

1654

2966

break;

1655

2967

}

1656

struct timespec sleeptime = { .tv_nsec = 250000000 };

1657

ret = nanosleep(&sleeptime, NULL);

1658

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

1659

perror_plus("nanosleep");

1660

}

1661

}

1662

if(not take_down_interface){

1663

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

1664

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

1665

if(ret == -1){

1666

perror_plus("close");

1667

}

1668

}

1669

#ifdef __linux__

1670

if(restore_loglevel){

1671

/* Restores kernel loglevel to default */

1672

ret = klogctl(7, NULL, 0);

1673

if(ret == -1){

1674

perror_plus("klogctl");

1675

}

1676

}

1677

#endif /* __linux__ */

1678

/* Lower privileges */

1679

errno = 0;

1680

if(take_down_interface){

1681

/* Lower privileges */

1682

ret = seteuid(uid);

1683

if(ret == -1){

1684

perror_plus("seteuid");

1685

}

1686

} else {

1687

/* Lower privileges permanently */

1688

ret = setuid(uid);

1689

if(ret == -1){

1690

perror_plus("setuid");

1691

}

1692

}

2968

bool interface_was_up = interface_is_up(interface);

2969

errno = bring_up_interface(interface, delay);

2970

if(not interface_was_up){

2971

if(errno != 0){

2972

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

2973

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

2974

} else {

2975

errno = argz_add(&interfaces_to_take_down,

2976

&interfaces_to_take_down_size,

2977

interface);

2978

if(errno != 0){

2979

perror_plus("argz_add");

2980

}

2981

}

2982

}

2983

}

2984

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

2985

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

2986

}

2987

}

2988

2989

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

2990

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

2991

if(debug){

2992

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

2993

mc.interfaces);

2994

}

2995

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

1693

2996

}

1694

2997

1695

2998

if(quit_now){

1696

2999

goto end;

1697

3000

}

1698

3001

1699

ret = init_gnutls_global(pubkey, seckey);

3002

#if GNUTLS_VERSION_NUMBER >= 0x030606

3003

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

3004

#elif GNUTLS_VERSION_NUMBER < 0x030600

3005

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

3006

#else

3007

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

3008

#endif

1700

3009

if(ret == -1){

1701

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

3010

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

1702

3011

exitcode = EX_UNAVAILABLE;

1703

3012

goto end;

1704

3013

} else {

1709

3018

goto end;

1710

3019

}

1711

3020

1712

if(mkdtemp(tempdir) == NULL){

3021

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

3022

tempdir = mkdtemp(run_tempdir);

3023

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

3024

if(debug){

3025

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

3026

run_tempdir, old_tempdir);

3027

}

3028

tempdir = mkdtemp(old_tempdir);

3029

}

3030

if(tempdir == NULL){

1713

3031

perror_plus("mkdtemp");

1714

3032

goto end;

1715

3033

}

1716

tempdir_created = true;

1717

3034

1718

3035

if(quit_now){

1719

3036

goto end;

1720

3037

}

1721

3038

1722

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

1723

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

3039

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

3040

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

1724

3041

exitcode = EX_UNAVAILABLE;

1725

3042

goto end;

1726

3043

} else {

1735

3052

/* Connect directly, do not use Zeroconf */

1736

3053

/* (Mainly meant for debugging) */

1737

3054

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

3055

1738

3056

if(address == NULL){

1739

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

3057

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

1740

3058

exitcode = EX_USAGE;

1741

3059

goto end;

1742

3060

}

1745

3063

goto end;

1746

3064

}

1747

3065

1748

uint16_t port;

3066

in_port_t port;

1749

3067

errno = 0;

1750

3068

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

1751

3069

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

1752

or tmpmax != (uint16_t)tmpmax){

1753

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

3070

or tmpmax != (in_port_t)tmpmax){

3071

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

1754

3072

exitcode = EX_USAGE;

1755

3073

goto end;

1756

3074

}

1757

3075

1758

3076

if(quit_now){

1759

3077

goto end;

1760

3078

}

1761

3079

1762

port = (uint16_t)tmpmax;

3080

port = (in_port_t)tmpmax;

1763

3081

*address = '\0';

1764

address = connect_to;

1765

3082

/* Colon in address indicates IPv6 */

1766

3083

int af;

1767

if(strchr(address, ':') != NULL){

3084

if(strchr(connect_to, ':') != NULL){

1768

3085

af = AF_INET6;

3086

/* Accept [] around IPv6 address - see RFC 5952 */

3087

if(connect_to[0] == '[' and address[-1] == ']')

3088

{

3089

connect_to++;

3090

address[-1] = '\0';

3091

}

1769

3092

} else {

1770

3093

af = AF_INET;

1771

3094

}

3095

address = connect_to;

1772

3096

1773

3097

if(quit_now){

1774

3098

goto end;

1775

3099

}

1776

3100

1777

3101

while(not quit_now){

1778

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

3102

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

3103

&mc);

1779

3104

if(quit_now or ret == 0){

1780

3105

break;

1781

3106

}

1782

sleep((int)retry_interval or 1);

1783

};

1784

1785

if (not quit_now){

3107

if(debug){

3108

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

3109

(int)retry_interval);

3110

}

3111

sleep((unsigned int)retry_interval);

3112

}

3113

3114

if(not quit_now){

1786

3115

exitcode = EXIT_SUCCESS;

1787

3116

}

1788

3117

1789

3118

goto end;

1790

3119

}

1791

3120

1803

3132

config.publish_domain = 0;

1804

3133

1805

3134

/* Allocate a new server */

1806

mc.server = avahi_server_new(avahi_simple_poll_get

1807

(mc.simple_poll), &config, NULL,

1808

NULL, &error);

3135

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3136

&config, NULL, NULL, &ret);

1809

3137

1810

3138

/* Free the Avahi configuration data */

1811

3139

avahi_server_config_free(&config);

1813

3141

1814

3142

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

1815

3143

if(mc.server == NULL){

1816

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

1817

avahi_strerror(error));

3144

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

3145

avahi_strerror(ret));

1818

3146

exitcode = EX_UNAVAILABLE;

1819

3147

goto end;

1820

3148

}

1826

3154

/* Create the Avahi service browser */

1827

3155

sb = avahi_s_service_browser_new(mc.server, if_index,

1828

3156

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

1829

NULL, 0, browse_callback, NULL);

3157

NULL, 0, browse_callback,

3158

(void *)&mc);

1830

3159

if(sb == NULL){

1831

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

1832

avahi_strerror(avahi_server_errno(mc.server)));

3160

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

3161

avahi_strerror(avahi_server_errno(mc.server)));

1833

3162

exitcode = EX_UNAVAILABLE;

1834

3163

goto end;

1835

3164

}

1841

3170

/* Run the main loop */

1842

3171

1843

3172

if(debug){

1844

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

3173

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

1845

3174

}

1846

1847

ret = avahi_loop_with_timeout(mc.simple_poll, (int)(retry_interval * 1000));

3175

3176

ret = avahi_loop_with_timeout(simple_poll,

3177

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

1848

3178

if(debug){

1849

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

1850

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

3179

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

3180

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

1851

3181

}

1852

3182

1853

3183

end:

1854

3184

1855

3185

if(debug){

1856

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

3186

if(signal_received){

3187

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

3188

argv[0], signal_received,

3189

strsignal(signal_received));

3190

} else {

3191

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

3192

}

1857

3193

}

1858

3194

1859

3195

/* Cleanup things */

3196

free(mc.interfaces);

3197

1860

3198

if(sb != NULL)

1861

3199

avahi_s_service_browser_free(sb);

1862

3200

1863

3201

if(mc.server != NULL)

1864

3202

avahi_server_free(mc.server);

1865

3203

1866

if(mc.simple_poll != NULL)

1867

avahi_simple_poll_free(mc.simple_poll);

3204

if(simple_poll != NULL)

3205

avahi_simple_poll_free(simple_poll);

1868

3206

1869

3207

if(gnutls_initialized){

1870

3208

gnutls_certificate_free_credentials(mc.cred);

1871

gnutls_global_deinit();

1872

3209

gnutls_dh_params_deinit(mc.dh_params);

1873

3210

}

1874

3211

1875

3212

if(gpgme_initialized){

1876

3213

gpgme_release(mc.ctx);

1877

3214

}

1878

1879

/* cleans up the circular linked list of mandos servers the client has seen */

3215

3216

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

3217

has seen */

1880

3218

if(mc.current_server != NULL){

1881

3219

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

1882

3220

while(mc.current_server != NULL){

1883

3221

server *next = mc.current_server->next;

3222

#ifdef __GNUC__

3223

#pragma GCC diagnostic push

3224

#pragma GCC diagnostic ignored "-Wcast-qual"

3225

#endif

3226

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

3227

#ifdef __GNUC__

3228

#pragma GCC diagnostic pop

3229

#endif

1884

3230

free(mc.current_server);

1885

3231

mc.current_server = next;

1886

3232

}

1887

3233

}

1888

3234

1889

/* Take down the network interface */

1890

if(take_down_interface){

1891

/* Re-raise priviliges */

1892

errno = 0;

1893

ret = seteuid(0);

1894

if(ret == -1){

1895

perror_plus("seteuid");

1896

}

1897

if(geteuid() == 0){

1898

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

1899

if(ret == -1){

1900

perror_plus("ioctl SIOCGIFFLAGS");

1901

} else if(network.ifr_flags & IFF_UP) {

1902

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

1903

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

1904

if(ret == -1){

1905

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

1906

}

1907

}

1908

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

1909

if(ret == -1){

1910

perror_plus("close");

1911

}

1912

/* Lower privileges permanently */

1913

errno = 0;

1914

ret = setuid(uid);

1915

if(ret == -1){

1916

perror_plus("setuid");

1917

}

1918

}

3235

/* Re-raise privileges */

3236

{

3237

ret = raise_privileges();

3238

if(ret != 0){

3239

errno = ret;

3240

perror_plus("Failed to raise privileges");

3241

} else {

3242

3243

/* Run network hooks */

3244

run_network_hooks("stop", interfaces_hooks != NULL ?

3245

interfaces_hooks : "", delay);

3246

3247

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

3248

{

3249

char *interface = NULL;

3250

while((interface = argz_next(interfaces_to_take_down,

3251

interfaces_to_take_down_size,

3252

interface))){

3253

ret = take_down_interface(interface);

3254

if(ret != 0){

3255

errno = ret;

3256

perror_plus("Failed to take down interface");

3257

}

3258

}

3259

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

3260

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

3261

" down\n");

3262

}

3263

}

3264

}

3265

3266

ret = lower_privileges_permanently();

3267

if(ret != 0){

3268

errno = ret;

3269

perror_plus("Failed to lower privileges permanently");

3270

}

3271

}

3272

3273

free(interfaces_to_take_down);

3274

free(interfaces_hooks);

3275

3276

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

3277

uintmax_t level){

3278

struct dirent **direntries = NULL;

3279

int dret;

3280

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

3281

O_RDONLY

3282

| O_NOFOLLOW

3283

| O_DIRECTORY

3284

| O_PATH));

3285

if(dir_fd == -1){

3286

perror_plus("open");

3287

return;

3288

}

3289

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

3290

notdotentries, alphasort);

3291

if(numentries >= 0){

3292

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

3293

if(debug){

3294

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

3295

dirname, direntries[i]->d_name);

3296

}

3297

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

3298

if(dret == -1){

3299

if(errno == EISDIR){

3300

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

3301

AT_REMOVEDIR);

3302

}

3303

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

3304

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

3305

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

3306

/* Recurse only in this special case */

3307

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

3308

dret = 0;

3309

}

3310

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

3311

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

3312

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

3313

}

3314

}

3315

free(direntries[i]);

3316

}

3317

3318

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

3319

free(direntries);

3320

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3321

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

3322

perror_plus("rmdir");

3323

}

3324

} else {

3325

perror_plus("scandirat");

3326

}

3327

close(dir_fd);

1919

3328

}

1920

3329

1921

3330

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

1922

if(tempdir_created){

1923

struct dirent **direntries = NULL;

1924

struct dirent *direntry = NULL;

1925

ret = scandir(tempdir, &direntries, notdotentries, alphasort);

1926

if (ret > 0){

1927

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

1928

direntry = direntries[i];

1929

char *fullname = NULL;

1930

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

1931

direntry->d_name);

1932

if(ret < 0){

1933

perror_plus("asprintf");

1934

continue;

1935

}

1936

ret = remove(fullname);

1937

if(ret == -1){

1938

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

1939

strerror(errno));

1940

}

1941

free(fullname);

1942

}

1943

}

1944

1945

/* need to be cleaned even if ret == 0 because man page dont specify */

1946

free(direntries);

1947

if (ret == -1){

1948

perror_plus("scandir");

1949

}

1950

ret = rmdir(tempdir);

1951

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

1952

perror_plus("rmdir");

1953

}

3331

if(tempdir != NULL){

3332

clean_dir_at(-1, tempdir, 0);

1954

3333

}

1955

3334

1956

3335

if(quit_now){