/mandos/release : revision 237.7.763

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

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*

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* Everything else is

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*

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

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

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

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

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*

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

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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* along with this program. If not, see

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

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif

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#endif /* not _LARGEFILE_SOURCE */

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif

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#endif /* not _FILE_OFFSET_BITS */

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

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

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stdout, ferror(), remove() */

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

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stdout, ferror() */

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

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

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

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strtof(), abort() */

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

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

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect() */

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

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inet_pton(), connect(),

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getnameinfo() */

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

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

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*/

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

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strtoimax() */

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

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

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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program_invocation_short_name */

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

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

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*/

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

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

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setgid(), pause() */

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

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

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unlinkat() */

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

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

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

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argp_state, struct argp,

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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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#elif GNUTLS_VERSION_NUMBER >= 0x030606

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

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GNUTLS_PKCS_PLAIN,

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GNUTLS_PKCS_NULL_PASSWORD */

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#endif

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/* GPGME */

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

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

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#define SECKEY "seckey.txt"

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#define PUBKEY "pubkey.txt"

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#define TLS_PRIVKEY "tls-privkey.pem"

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#define TLS_PUBKEY "tls-pubkey.pem"

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

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bool debug = false;

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

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char *connect_to = NULL;

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const char *hookdir = HOOKDIR;

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int hookdir_fd = -1;

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uid_t uid = 65534;

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gid_t gid = 65534;

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

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typedef struct server{

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const char *ip;

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uint16_t port;

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in_port_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

217

__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(buffer == NULL){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

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}

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return buffer_capacity;

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}

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

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

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int af){

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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int ret;

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

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if(new_server == NULL){

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perror_plus("malloc");

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return -1;

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return false;

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}

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

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.port = port,

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.af = af };

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if(new_server->ip == NULL){

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perror_plus("strdup");

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return -1;

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free(new_server);

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return false;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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#ifdef __GNUC__

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#pragma GCC diagnostic push

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#pragma GCC diagnostic ignored "-Wcast-qual"

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#endif

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

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#ifdef __GNUC__

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#pragma GCC diagnostic pop

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#endif

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free(new_server);

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return false;

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}

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/* Special case of first server */

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if (mc.current_server == NULL){

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if(*current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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mc.current_server = new_server;

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

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*current_server = new_server;

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} else {

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new_server->next = mc.current_server;

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

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

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new_server->next = *current_server;

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

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new_server->prev->next = new_server;

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mc.current_server->prev = new_server;

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}

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

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if(ret == -1){

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perror_plus("clock_gettime");

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return -1;

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}

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return 0;

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(*current_server)->prev = new_server;

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}

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return true;

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}

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

284

__attribute__((warn_unused_result))

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int raise_privileges(void){

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int old_errno = errno;

287

int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

292

return ret;

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}

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

296

__attribute__((warn_unused_result))

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int raise_privileges_permanently(void){

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int old_errno = errno;

299

int ret = raise_privileges();

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if(ret != 0){

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errno = old_errno;

302

return ret;

303

}

304

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

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ret = errno;

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}

307

errno = old_errno;

308

return ret;

309

}

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

312

__attribute__((warn_unused_result))

313

int lower_privileges(void){

314

int old_errno = errno;

315

int ret = 0;

316

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

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ret = errno;

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}

319

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))

325

int lower_privileges_permanently(void){

326

int old_errno = errno;

327

int ret = 0;

328

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

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ret = errno;

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}

331

errno = old_errno;

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return ret;

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}

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/*

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* Initialize GPGME.

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337

*/

243

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

244

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,

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mandos_context *mc){

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343

gpgme_error_t rc;

246

344

gpgme_engine_info_t engine_info;

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345

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/*

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347

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

251

348

*/

252

bool import_key(const char *filename){

349

bool import_key(const char * const filename){

253

350

int ret;

254

351

int fd;

255

352

gpgme_data_t pgp_data;

260

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return false;

261

358

}

262

359

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

361

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

362

do {

363

{

364

time_t currtime = time(NULL);

365

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

366

struct tm tm;

367

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

368

perror_plus("gmtime_r");

369

break;

370

}

371

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

372

break;

373

}

374

if(debug){

375

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

376

}

377

} else {

378

if(debug){

379

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

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

time_t keytime = keystat.st_mtim.tv_sec;

400

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

401

perror_plus("stime");

402

}

403

ret = lower_privileges();

404

if(ret != 0){

405

errno = ret;

406

perror_plus("Failed to lower privileges");

407

}

408

} while(false);

409

263

410

rc = gpgme_data_new_from_fd(&pgp_data, fd);

264

411

if(rc != GPG_ERR_NO_ERROR){

265

412

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

267

414

return false;

268

415

}

269

416

270

rc = gpgme_op_import(mc.ctx, pgp_data);

417

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

271

418

if(rc != GPG_ERR_NO_ERROR){

272

419

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

273

420

gpgme_strsource(rc), gpgme_strerror(rc));

274

421

return false;

275

422

}

423

{

424

gpgme_import_result_t import_result

425

= gpgme_op_import_result(mc->ctx);

426

if((import_result->imported < 1

427

or import_result->not_imported > 0)

428

and import_result->unchanged == 0){

429

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

430

fprintf_plus(stderr,

431

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

432

import_result->considered);

433

fprintf_plus(stderr,

434

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

435

import_result->no_user_id);

436

fprintf_plus(stderr,

437

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

438

import_result->imported);

439

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

440

import_result->imported_rsa);

441

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

442

import_result->unchanged);

443

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

444

import_result->new_user_ids);

445

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

446

import_result->new_sub_keys);

447

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

448

import_result->new_signatures);

449

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

450

import_result->new_revocations);

451

fprintf_plus(stderr,

452

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

453

import_result->secret_read);

454

fprintf_plus(stderr,

455

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

456

import_result->secret_imported);

457

fprintf_plus(stderr,

458

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

459

import_result->secret_unchanged);

460

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

461

import_result->not_imported);

462

for(gpgme_import_status_t import_status

463

= import_result->imports;

464

import_status != NULL;

465

import_status = import_status->next){

466

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

467

import_status->fpr);

468

if(import_status->result != GPG_ERR_NO_ERROR){

469

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

470

gpgme_strsource(import_status->result),

471

gpgme_strerror(import_status->result));

472

}

473

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

474

fprintf_plus(stderr,

475

import_status->status & GPGME_IMPORT_NEW

476

? "The key was new.\n"

477

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

478

fprintf_plus(stderr,

479

import_status->status & GPGME_IMPORT_UID

480

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

481

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

482

fprintf_plus(stderr,

483

import_status->status & GPGME_IMPORT_SIG

484

? "The key contained new signatures.\n"

485

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

486

fprintf_plus(stderr,

487

import_status->status & GPGME_IMPORT_SUBKEY

488

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

489

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

490

fprintf_plus(stderr,

491

import_status->status & GPGME_IMPORT_SECRET

492

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

493

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

494

}

495

return false;

496

}

497

}

276

498

277

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

499

ret = close(fd);

278

500

if(ret == -1){

279

501

perror_plus("close");

280

502

}

317

539

}

318

540

319

541

/* Create new GPGME "context" */

320

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

542

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

321

543

if(rc != GPG_ERR_NO_ERROR){

322

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

323

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

324

gpgme_strerror(rc));

544

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

545

gpgme_strsource(rc), gpgme_strerror(rc));

325

546

return false;

326

547

}

327

548

336

557

* Decrypt OpenPGP data.

337

558

* Returns -1 on error

338

559

*/

560

__attribute__((nonnull, warn_unused_result))

339

561

static ssize_t pgp_packet_decrypt(const char *cryptotext,

340

562

size_t crypto_size,

341

char **plaintext){

563

char **plaintext,

564

mandos_context *mc){

342

565

gpgme_data_t dh_crypto, dh_plain;

343

566

gpgme_error_t rc;

344

567

ssize_t ret;

361

584

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

362

585

rc = gpgme_data_new(&dh_plain);

363

586

if(rc != GPG_ERR_NO_ERROR){

364

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

365

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

587

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

366

588

gpgme_strsource(rc), gpgme_strerror(rc));

367

589

gpgme_data_release(dh_crypto);

368

590

return -1;

370

592

371

593

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

372

594

data buffer */

373

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

595

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

374

596

if(rc != GPG_ERR_NO_ERROR){

375

597

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

376

598

gpgme_strsource(rc), gpgme_strerror(rc));

377

599

plaintext_length = -1;

378

600

if(debug){

379

601

gpgme_decrypt_result_t result;

380

result = gpgme_op_decrypt_result(mc.ctx);

602

result = gpgme_op_decrypt_result(mc->ctx);

381

603

if(result == NULL){

382

604

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

383

605

} else {

384

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

385

result->unsupported_algorithm);

386

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

387

result->wrong_key_usage);

606

if(result->unsupported_algorithm != NULL) {

607

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

608

result->unsupported_algorithm);

609

}

610

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

611

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

388

612

if(result->file_name != NULL){

389

613

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

390

614

}

391

gpgme_recipient_t recipient;

392

recipient = result->recipients;

393

while(recipient != NULL){

615

616

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

617

r = r->next){

394

618

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

395

gpgme_pubkey_algo_name

396

(recipient->pubkey_algo));

397

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

619

gpgme_pubkey_algo_name(r->pubkey_algo));

620

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

398

621

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

399

recipient->status == GPG_ERR_NO_SECKEY

400

? "No" : "Yes");

401

recipient = recipient->next;

622

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

402

623

}

403

624

}

404

625

}

460

681

return plaintext_length;

461

682

}

462

683

463

static const char * safer_gnutls_strerror(int value){

464

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

465

-Wunreachable-code */

466

if(ret == NULL)

467

ret = "(unknown)";

468

return ret;

684

__attribute__((warn_unused_result, const))

685

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

686

if(str == NULL)

687

return "(unknown)";

688

return str;

689

}

690

691

__attribute__((warn_unused_result))

692

static const char *safer_gnutls_strerror(int value){

693

const char *ret = gnutls_strerror(value);

694

return safe_string(ret);

469

695

}

470

696

471

697

/* GnuTLS log function callback */

698

__attribute__((nonnull))

472

699

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

473

700

const char* string){

474

701

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

475

702

}

476

703

704

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

477

705

static int init_gnutls_global(const char *pubkeyfilename,

478

const char *seckeyfilename){

706

const char *seckeyfilename,

707

const char *dhparamsfilename,

708

mandos_context *mc){

479

709

int ret;

480

710

481

711

if(debug){

482

712

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

483

713

}

484

714

485

ret = gnutls_global_init();

486

if(ret != GNUTLS_E_SUCCESS){

487

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

488

safer_gnutls_strerror(ret));

489

return -1;

490

}

491

492

715

if(debug){

493

716

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

494

717

* - GnuTLS manual

498

721

}

499

722

500

723

/* OpenPGP credentials */

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

724

ret = gnutls_certificate_allocate_credentials(&mc->cred);

502

725

if(ret != GNUTLS_E_SUCCESS){

503

726

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

504

727

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

506

728

return -1;

507

729

}

508

730

509

731

if(debug){

510

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

511

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

732

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

733

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

512

734

pubkeyfilename,

513

735

seckeyfilename);

514

736

}

515

737

738

#if GNUTLS_VERSION_NUMBER >= 0x030606

739

ret = gnutls_certificate_set_rawpk_key_file

740

(mc->cred, pubkeyfilename, seckeyfilename,

741

GNUTLS_X509_FMT_PEM, /* format */

742

NULL, /* pass */

743

/* key_usage */

744

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

745

NULL, /* names */

746

0, /* names_length */

747

/* privkey_flags */

748

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

749

0); /* pkcs11_flags */

750

#elif GNUTLS_VERSION_NUMBER < 0x030600

516

751

ret = gnutls_certificate_set_openpgp_key_file

517

(mc.cred, pubkeyfilename, seckeyfilename,

752

(mc->cred, pubkeyfilename, seckeyfilename,

518

753

GNUTLS_OPENPGP_FMT_BASE64);

754

#else

755

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

756

#endif

519

757

if(ret != GNUTLS_E_SUCCESS){

520

758

fprintf_plus(stderr,

521

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

759

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

522

760

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

523

761

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

524

762

safer_gnutls_strerror(ret));

526

764

}

527

765

528

766

/* GnuTLS server initialization */

529

ret = gnutls_dh_params_init(&mc.dh_params);

767

ret = gnutls_dh_params_init(&mc->dh_params);

530

768

if(ret != GNUTLS_E_SUCCESS){

531

769

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

532

770

" initialization: %s\n",

533

771

safer_gnutls_strerror(ret));

534

772

goto globalfail;

535

773

}

536

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

537

if(ret != GNUTLS_E_SUCCESS){

538

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

539

safer_gnutls_strerror(ret));

540

goto globalfail;

541

}

542

543

gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);

774

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

775

if(dhparamsfilename != NULL){

776

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

777

do {

778

int dhpfile = open(dhparamsfilename, O_RDONLY);

779

if(dhpfile == -1){

780

perror_plus("open");

781

dhparamsfilename = NULL;

782

break;

783

}

784

size_t params_capacity = 0;

785

while(true){

786

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

787

(size_t)params.size,

788

(size_t)params_capacity);

789

if(params_capacity == 0){

790

perror_plus("incbuffer");

791

free(params.data);

792

params.data = NULL;

793

dhparamsfilename = NULL;

794

break;

795

}

796

ssize_t bytes_read = read(dhpfile,

797

params.data + params.size,

798

BUFFER_SIZE);

799

/* EOF */

800

if(bytes_read == 0){

801

break;

802

}

803

/* check bytes_read for failure */

804

if(bytes_read < 0){

805

perror_plus("read");

806

free(params.data);

807

params.data = NULL;

808

dhparamsfilename = NULL;

809

break;

810

}

811

params.size += (unsigned int)bytes_read;

812

}

813

ret = close(dhpfile);

814

if(ret == -1){

815

perror_plus("close");

816

}

817

if(params.data == NULL){

818

dhparamsfilename = NULL;

819

}

820

if(dhparamsfilename == NULL){

821

break;

822

}

823

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

824

GNUTLS_X509_FMT_PEM);

825

if(ret != GNUTLS_E_SUCCESS){

826

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

827

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

828

safer_gnutls_strerror(ret));

829

dhparamsfilename = NULL;

830

}

831

free(params.data);

832

} while(false);

833

}

834

if(dhparamsfilename == NULL){

835

if(mc->dh_bits == 0){

836

#if GNUTLS_VERSION_NUMBER < 0x030600

837

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

838

/* Try to read the private key file */

839

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

840

do {

841

int secfile = open(seckeyfilename, O_RDONLY);

842

if(secfile == -1){

843

perror_plus("open");

844

break;

845

}

846

size_t buffer_capacity = 0;

847

while(true){

848

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

849

(size_t)buffer.size,

850

(size_t)buffer_capacity);

851

if(buffer_capacity == 0){

852

perror_plus("incbuffer");

853

free(buffer.data);

854

buffer.data = NULL;

855

break;

856

}

857

ssize_t bytes_read = read(secfile,

858

buffer.data + buffer.size,

859

BUFFER_SIZE);

860

/* EOF */

861

if(bytes_read == 0){

862

break;

863

}

864

/* check bytes_read for failure */

865

if(bytes_read < 0){

866

perror_plus("read");

867

free(buffer.data);

868

buffer.data = NULL;

869

break;

870

}

871

buffer.size += (unsigned int)bytes_read;

872

}

873

close(secfile);

874

} while(false);

875

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

876

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

877

if(buffer.data != NULL){

878

{

879

gnutls_openpgp_privkey_t privkey = NULL;

880

ret = gnutls_openpgp_privkey_init(&privkey);

881

if(ret != GNUTLS_E_SUCCESS){

882

fprintf_plus(stderr, "Error initializing OpenPGP key"

883

" structure: %s",

884

safer_gnutls_strerror(ret));

885

free(buffer.data);

886

buffer.data = NULL;

887

} else {

888

ret = gnutls_openpgp_privkey_import

889

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

890

if(ret != GNUTLS_E_SUCCESS){

891

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

892

safer_gnutls_strerror(ret));

893

privkey = NULL;

894

}

895

free(buffer.data);

896

buffer.data = NULL;

897

if(privkey != NULL){

898

/* Use private key to suggest an appropriate

899

sec_param */

900

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

901

gnutls_openpgp_privkey_deinit(privkey);

902

if(debug){

903

fprintf_plus(stderr, "This OpenPGP key implies using"

904

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

905

safe_string(gnutls_sec_param_get_name

906

(sec_param)));

907

}

908

}

909

}

910

}

911

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

912

/* Err on the side of caution */

913

sec_param = GNUTLS_SEC_PARAM_ULTRA;

914

if(debug){

915

fprintf_plus(stderr, "Falling back to security parameter"

916

" \"%s\"\n",

917

safe_string(gnutls_sec_param_get_name

918

(sec_param)));

919

}

920

}

921

}

922

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

923

if(uret != 0){

924

mc->dh_bits = uret;

925

if(debug){

926

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

927

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

928

safe_string(gnutls_sec_param_get_name

929

(sec_param)),

930

mc->dh_bits);

931

}

932

} else {

933

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

934

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

935

safe_string(gnutls_sec_param_get_name

936

(sec_param)),

937

safer_gnutls_strerror(ret));

938

goto globalfail;

939

}

940

#endif

941

} else { /* dh_bits != 0 */

942

if(debug){

943

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

944

mc->dh_bits);

945

}

946

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

947

if(ret != GNUTLS_E_SUCCESS){

948

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

949

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

950

safer_gnutls_strerror(ret));

951

goto globalfail;

952

}

953

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

954

}

955

}

544

956

545

957

return 0;

546

958

547

959

globalfail:

548

960

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

961

gnutls_certificate_free_credentials(mc->cred);

962

gnutls_dh_params_deinit(mc->dh_params);

552

963

return -1;

553

964

}

554

965

555

static int init_gnutls_session(gnutls_session_t *session){

966

__attribute__((nonnull, warn_unused_result))

967

static int init_gnutls_session(gnutls_session_t *session,

968

mandos_context *mc){

556

969

int ret;

557

970

/* GnuTLS session creation */

558

971

do {

559

ret = gnutls_init(session, GNUTLS_SERVER);

972

ret = gnutls_init(session, (GNUTLS_SERVER

973

#if GNUTLS_VERSION_NUMBER >= 0x030506

974

| GNUTLS_NO_TICKETS

975

#endif

976

#if GNUTLS_VERSION_NUMBER >= 0x030606

977

| GNUTLS_ENABLE_RAWPK

978

#endif

979

));

560

980

if(quit_now){

561

981

return -1;

562

982

}

570

990

{

571

991

const char *err;

572

992

do {

573

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

993

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

574

994

if(quit_now){

575

995

gnutls_deinit(*session);

576

996

return -1;

587

1007

588

1008

do {

589

1009

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

590

mc.cred);

1010

mc->cred);

591

1011

if(quit_now){

592

1012

gnutls_deinit(*session);

593

1013

return -1;

603

1023

/* ignore client certificate if any. */

604

1024

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

605

1025

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

608

1026

return 0;

609

1027

}

610

1028

612

1030

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

613

1031

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

614

1032

1033

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

1034

__attribute__((nonnull, warn_unused_result))

1035

static bool add_delete_local_route(const bool add,

1036

const char *address,

1037

AvahiIfIndex if_index){

1038

int ret;

1039

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

1040

char add_arg[] = "add";

1041

char delete_arg[] = "delete";

1042

char debug_flag[] = "--debug";

1043

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1044

if(pluginhelperdir == NULL){

1045

if(debug){

1046

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1047

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

1048

}

1049

return false;

1050

}

1051

1052

char interface[IF_NAMESIZE];

1053

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

1054

perror_plus("if_indextoname");

1055

return false;

1056

}

1057

1058

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

1059

if(devnull == -1){

1060

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

1061

return false;

1062

}

1063

pid_t pid = fork();

1064

if(pid == 0){

1065

/* Child */

1066

/* Raise privileges */

1067

errno = raise_privileges_permanently();

1068

if(errno != 0){

1069

perror_plus("Failed to raise privileges");

1070

/* _exit(EX_NOPERM); */

1071

} else {

1072

/* Set group */

1073

errno = 0;

1074

ret = setgid(0);

1075

if(ret == -1){

1076

perror_plus("setgid");

1077

close(devnull);

1078

_exit(EX_NOPERM);

1079

}

1080

/* Reset supplementary groups */

1081

errno = 0;

1082

ret = setgroups(0, NULL);

1083

if(ret == -1){

1084

perror_plus("setgroups");

1085

close(devnull);

1086

_exit(EX_NOPERM);

1087

}

1088

}

1089

ret = dup2(devnull, STDIN_FILENO);

1090

if(ret == -1){

1091

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

1092

close(devnull);

1093

_exit(EX_OSERR);

1094

}

1095

ret = close(devnull);

1096

if(ret == -1){

1097

perror_plus("close");

1098

}

1099

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1100

if(ret == -1){

1101

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

1102

_exit(EX_OSERR);

1103

}

1104

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

1105

O_RDONLY

1106

| O_DIRECTORY

1107

| O_PATH

1108

| O_CLOEXEC));

1109

if(helperdir_fd == -1){

1110

perror_plus("open");

1111

_exit(EX_UNAVAILABLE);

1112

}

1113

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

1114

helper, O_RDONLY));

1115

if(helper_fd == -1){

1116

perror_plus("openat");

1117

close(helperdir_fd);

1118

_exit(EX_UNAVAILABLE);

1119

}

1120

close(helperdir_fd);

1121

#ifdef __GNUC__

1122

#pragma GCC diagnostic push

1123

#pragma GCC diagnostic ignored "-Wcast-qual"

1124

#endif

1125

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

1126

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

1127

interface, debug ? debug_flag : NULL, NULL },

1128

environ) == -1){

1129

#ifdef __GNUC__

1130

#pragma GCC diagnostic pop

1131

#endif

1132

perror_plus("fexecve");

1133

_exit(EXIT_FAILURE);

1134

}

1135

}

1136

if(pid == -1){

1137

perror_plus("fork");

1138

close(devnull);

1139

return false;

1140

}

1141

ret = close(devnull);

1142

if(ret == -1){

1143

perror_plus("close");

1144

}

1145

int status;

1146

pid_t pret = -1;

1147

errno = 0;

1148

do {

1149

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

1150

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

1151

int errno_raising = 0;

1152

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

1153

errno_raising = errno;

1154

perror_plus("Failed to raise privileges in order to"

1155

" kill helper program");

1156

}

1157

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

1158

perror_plus("kill");

1159

}

1160

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

1161

perror_plus("Failed to lower privileges after killing"

1162

" helper program");

1163

}

1164

return false;

1165

}

1166

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

1167

if(pret == -1){

1168

perror_plus("waitpid");

1169

return false;

1170

}

1171

if(WIFEXITED(status)){

1172

if(WEXITSTATUS(status) != 0){

1173

fprintf_plus(stderr, "Error: iprouteadddel exited"

1174

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

1175

return false;

1176

}

1177

return true;

1178

}

1179

if(WIFSIGNALED(status)){

1180

fprintf_plus(stderr, "Error: iprouteadddel died by"

1181

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

1182

return false;

1183

}

1184

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

1185

return false;

1186

}

1187

1188

__attribute__((nonnull, warn_unused_result))

1189

static bool add_local_route(const char *address,

1190

AvahiIfIndex if_index){

1191

if(debug){

1192

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

1193

}

1194

return add_delete_local_route(true, address, if_index);

1195

}

1196

1197

__attribute__((nonnull, warn_unused_result))

1198

static bool delete_local_route(const char *address,

1199

AvahiIfIndex if_index){

1200

if(debug){

1201

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

1202

}

1203

return add_delete_local_route(false, address, if_index);

1204

}

1205

615

1206

/* Called when a Mandos server is found */

616

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

1207

__attribute__((nonnull, warn_unused_result))

1208

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

617

1209

AvahiIfIndex if_index,

618

int af){

1210

int af, mandos_context *mc){

619

1211

int ret, tcp_sd = -1;

620

1212

ssize_t sret;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1213

struct sockaddr_storage to;

625

1214

char *buffer = NULL;

626

1215

char *decrypted_buffer = NULL;

627

1216

size_t buffer_length = 0;

630

1219

int retval = -1;

631

1220

gnutls_session_t session;

632

1221

int pf; /* Protocol family */

1222

bool route_added = false;

633

1223

634

1224

errno = 0;

635

1225

651

1241

return -1;

652

1242

}

653

1243

654

ret = init_gnutls_session(&session);

1244

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

1245

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

1246

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

1247

bool match = false;

1248

{

1249

char *interface = NULL;

1250

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

1251

mc->interfaces_size,

1252

interface))){

1253

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

1254

match = true;

1255

break;

1256

}

1257

}

1258

}

1259

if(not match){

1260

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

1261

connect to the server */

1262

if(debug){

1263

char interface[IF_NAMESIZE];

1264

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

1265

perror_plus("if_indextoname");

1266

} else {

1267

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

1268

" \"%s\"\n",

1269

if_indextoname((unsigned int)if_index,

1270

interface));

1271

}

1272

}

1273

return -1;

1274

}

1275

}

1276

1277

ret = init_gnutls_session(&session, mc);

655

1278

if(ret != 0){

656

1279

return -1;

657

1280

}

658

1281

659

1282

if(debug){

660

1283

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

661

PRIu16 "\n", ip, port);

1284

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

662

1285

}

663

1286

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1287

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

665

1288

if(tcp_sd < 0){

666

1289

int e = errno;

667

1290

perror_plus("socket");

674

1297

goto mandos_end;

675

1298

}

676

1299

677

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

678

1300

if(af == AF_INET6){

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1301

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

1302

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

1303

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

681

1304

} else { /* IPv4 */

682

to.in.sin_family = (sa_family_t)af;

683

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

1305

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

1306

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

1307

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

684

1308

}

685

1309

if(ret < 0 ){

686

1310

int e = errno;

695

1319

goto mandos_end;

696

1320

}

697

1321

if(af == AF_INET6){

698

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

699

-Wconversion and

700

-Wunreachable-code */

701

702

if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */

703

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

704

-Wunreachable-code*/

1322

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

1323

if(IN6_IS_ADDR_LINKLOCAL

1324

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

705

1325

if(if_index == AVAHI_IF_UNSPEC){

706

1326

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

707

1327

" incomplete without a network interface\n");

709

1329

goto mandos_end;

710

1330

}

711

1331

/* Set the network interface number as scope */

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1332

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

713

1333

}

714

1334

} else {

715

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

716

-Wconversion and

717

-Wunreachable-code */

1335

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

718

1336

}

719

1337

720

1338

if(quit_now){

728

1346

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

729

1347

perror_plus("if_indextoname");

730

1348

} else {

731

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

732

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

1349

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

1350

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

733

1351

}

734

1352

} else {

735

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

736

ip, port);

1353

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

1354

ip, (uintmax_t)port);

737

1355

}

738

1356

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

739

1357

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

740

const char *pcret;

741

if(af == AF_INET6){

742

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

743

sizeof(addrstr));

744

} else {

745

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

746

sizeof(addrstr));

747

}

748

if(pcret == NULL){

749

perror_plus("inet_ntop");

750

} else {

751

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

752

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

753

}

754

}

755

}

756

757

if(quit_now){

758

errno = EINTR;

759

goto mandos_end;

760

}

761

762

if(af == AF_INET6){

763

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

764

} else {

765

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

766

}

767

if(ret < 0){

768

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

769

int e = errno;

770

perror_plus("connect");

771

errno = e;

772

}

773

goto mandos_end;

774

}

775

776

if(quit_now){

777

errno = EINTR;

778

goto mandos_end;

1358

if(af == AF_INET6){

1359

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

1360

sizeof(struct sockaddr_in6),

1361

addrstr, sizeof(addrstr), NULL, 0,

1362

NI_NUMERICHOST);

1363

} else {

1364

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

1365

sizeof(struct sockaddr_in),

1366

addrstr, sizeof(addrstr), NULL, 0,

1367

NI_NUMERICHOST);

1368

}

1369

if(ret == EAI_SYSTEM){

1370

perror_plus("getnameinfo");

1371

} else if(ret != 0) {

1372

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

1373

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

1374

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

1375

}

1376

}

1377

1378

if(quit_now){

1379

errno = EINTR;

1380

goto mandos_end;

1381

}

1382

1383

while(true){

1384

if(af == AF_INET6){

1385

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

1386

sizeof(struct sockaddr_in6));

1387

} else {

1388

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

1389

sizeof(struct sockaddr_in));

1390

}

1391

if(ret < 0){

1392

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

1393

and if_index != AVAHI_IF_UNSPEC

1394

and connect_to == NULL

1395

and not route_added and

1396

((af == AF_INET6 and not

1397

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1398

&to)->sin6_addr)))

1399

or (af == AF_INET and

1400

/* Not a a IPv4LL address */

1401

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

1402

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

1403

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

1404

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

1405

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

1406

connect to a Mandos server announced by Avahi on a server

1407

host with a global address. Work around this by retrying

1408

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

1409

1410

Avahi bug reference:

1411

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

1412

https://bugs.debian.org/587961

1413

*/

1414

if(debug){

1415

fprintf_plus(stderr, "Mandos server unreachable, trying"

1416

" direct route\n");

1417

}

1418

int e = errno;

1419

route_added = add_local_route(ip, if_index);

1420

if(route_added){

1421

continue;

1422

}

1423

errno = e;

1424

}

1425

if(errno != ECONNREFUSED or debug){

1426

int e = errno;

1427

perror_plus("connect");

1428

errno = e;

1429

}

1430

goto mandos_end;

1431

}

1432

1433

if(quit_now){

1434

errno = EINTR;

1435

goto mandos_end;

1436

}

1437

break;

779

1438

}

780

1439

781

1440

const char *out = mandos_protocol_version;

817

1476

goto mandos_end;

818

1477

}

819

1478

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1479

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

1480

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

1481

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

1482

gnutls_transport_set_ptr(session,

1483

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

822

1484

823

1485

if(quit_now){

824

1486

errno = EINTR;

929

1591

if(buffer_length > 0){

930

1592

ssize_t decrypted_buffer_size;

931

1593

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

932

&decrypted_buffer);

1594

&decrypted_buffer, mc);

933

1595

if(decrypted_buffer_size >= 0){

934

1596

1597

clearerr(stdout);

935

1598

written = 0;

936

1599

while(written < (size_t) decrypted_buffer_size){

937

1600

if(quit_now){

953

1616

}

954

1617

written += (size_t)ret;

955

1618

}

1619

ret = fflush(stdout);

1620

if(ret != 0){

1621

int e = errno;

1622

if(debug){

1623

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

1624

strerror(errno));

1625

}

1626

errno = e;

1627

goto mandos_end;

1628

}

956

1629

retval = 0;

957

1630

}

958

1631

}

961

1634

962

1635

mandos_end:

963

1636

{

1637

if(route_added){

1638

if(not delete_local_route(ip, if_index)){

1639

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

1640

" interface %d", ip, if_index);

1641

}

1642

}

964

1643

int e = errno;

965

1644

free(decrypted_buffer);

966

1645

free(buffer);

967

1646

if(tcp_sd >= 0){

968

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

1647

ret = close(tcp_sd);

969

1648

}

970

1649

if(ret == -1){

971

1650

if(e == 0){

996

1675

AVAHI_GCC_UNUSED AvahiStringList *txt,

997

1676

AVAHI_GCC_UNUSED AvahiLookupResultFlags

998

1677

flags,

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1678

void *mc){

1679

if(r == NULL){

1680

return;

1681

}

1001

1682

1002

1683

/* Called whenever a service has been resolved successfully or

1003

1684

timed out */

1004

1685

1005

1686

if(quit_now){

1687

avahi_s_service_resolver_free(r);

1006

1688

return;

1007

1689

}

1008

1690

1012

1694

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

1013

1695

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

1014

1696

domain,

1015

avahi_strerror(avahi_server_errno(mc.server)));

1697

avahi_strerror(avahi_server_errno

1698

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

1016

1699

break;

1017

1700

1018

1701

case AVAHI_RESOLVER_FOUND:

1024

1707

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

1025

1708

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

1026

1709

}

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1710

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

1711

interface,

1712

avahi_proto_to_af(proto),

1713

mc);

1029

1714

if(ret == 0){

1030

avahi_simple_poll_quit(mc.simple_poll);

1715

avahi_simple_poll_quit(simple_poll);

1031

1716

} else {

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1717

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

1718

avahi_proto_to_af(proto),

1719

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

1720

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

1721

" list\n", name);

1722

}

1034

1723

}

1035

1724

}

1036

1725

}

1046

1735

const char *domain,

1047

1736

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1048

1737

flags,

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1738

void *mc){

1739

if(b == NULL){

1740

return;

1741

}

1051

1742

1052

1743

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

1053

1744

is removed from the LAN */

1061

1752

case AVAHI_BROWSER_FAILURE:

1062

1753

1063

1754

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

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1755

avahi_strerror(avahi_server_errno

1756

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

1757

avahi_simple_poll_quit(simple_poll);

1066

1758

return;

1067

1759

1068

1760

case AVAHI_BROWSER_NEW:

1071

1763

the callback function is called the Avahi server will free the

1072

1764

resolver for us. */

1073

1765

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1766

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

1767

interface, protocol, name, type,

1768

domain, protocol, 0,

1769

resolve_callback, mc) == NULL)

1077

1770

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

1078

1771

" %s\n", name,

1079

avahi_strerror(avahi_server_errno(mc.server)));

1772

avahi_strerror(avahi_server_errno

1773

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

1080

1774

break;

1081

1775

1082

1776

case AVAHI_BROWSER_REMOVE:

1101

1795

signal_received = sig;

1102

1796

int old_errno = errno;

1103

1797

/* set main loop to exit */

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1798

if(simple_poll != NULL){

1799

avahi_simple_poll_quit(simple_poll);

1106

1800

}

1107

1801

errno = old_errno;

1108

1802

}

1109

1803

1804

__attribute__((nonnull, warn_unused_result))

1110

1805

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

1111

1806

int ret;

1807

int old_errno;

1112

1808

1113

1809

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

1114

1810

if(s < 0){

1811

old_errno = errno;

1115

1812

perror_plus("socket");

1813

errno = old_errno;

1116

1814

return false;

1117

1815

}

1118

strcpy(ifr->ifr_name, ifname);

1816

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

1817

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

1119

1818

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1120

1819

if(ret == -1){

1121

1820

if(debug){

1821

old_errno = errno;

1122

1822

perror_plus("ioctl SIOCGIFFLAGS");

1823

errno = old_errno;

1824

}

1825

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

1826

old_errno = errno;

1827

perror_plus("close");

1828

errno = old_errno;

1123

1829

}

1124

1830

return false;

1125

1831

}

1832

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

1833

old_errno = errno;

1834

perror_plus("close");

1835

errno = old_errno;

1836

}

1126

1837

return true;

1127

1838

}

1128

1839

1840

__attribute__((nonnull, warn_unused_result))

1129

1841

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

1130

1842

1131

1843

/* Reject the loopback device */

1173

1885

* corresponds to an acceptable network device.

1174

1886

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

1175

1887

*/

1888

__attribute__((nonnull, warn_unused_result))

1176

1889

int good_interface(const struct dirent *if_entry){

1177

1890

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

1178

1891

return 0;

1194

1907

}

1195

1908

1196

1909

/*

1197

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

1198

* corresponds to an acceptable network device which is up.

1199

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

1200

*/

1201

int up_interface(const struct dirent *if_entry){

1202

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

1203

return 0;

1204

}

1205

1206

struct ifreq ifr;

1207

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

1208

if(debug){

1209

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

1210

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

1211

}

1212

return 0;

1213

}

1214

1215

/* Reject down interfaces */

1216

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

1217

if(debug){

1218

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

1219

if_entry->d_name);

1220

}

1221

return 0;

1222

}

1223

1224

/* Reject non-running interfaces */

1225

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

1226

if(debug){

1227

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

1228

if_entry->d_name);

1229

}

1230

return 0;

1231

}

1232

1233

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

1234

return 0;

1235

}

1236

return 1;

1237

}

1238

1910

* This function determines if a network interface is up.

1911

*/

1912

__attribute__((nonnull, warn_unused_result))

1913

bool interface_is_up(const char *interface){

1914

struct ifreq ifr;

1915

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

1916

if(debug){

1917

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

1918

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

1919

}

1920

return false;

1921

}

1922

1923

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

1924

}

1925

1926

/*

1927

* This function determines if a network interface is running

1928

*/

1929

__attribute__((nonnull, warn_unused_result))

1930

bool interface_is_running(const char *interface){

1931

struct ifreq ifr;

1932

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

1933

if(debug){

1934

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

1935

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

1936

}

1937

return false;

1938

}

1939

1940

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

1941

}

1942

1943

__attribute__((nonnull, pure, warn_unused_result))

1239

1944

int notdotentries(const struct dirent *direntry){

1240

1945

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

1241

1946

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

1248

1953

}

1249

1954

1250

1955

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

1956

__attribute__((nonnull, warn_unused_result))

1251

1957

int runnable_hook(const struct dirent *direntry){

1252

1958

int ret;

1253

1959

size_t sret;

1261

1967

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

1262

1968

"abcdefghijklmnopqrstuvwxyz"

1263

1969

"0123456789"

1264

"_-");

1970

"_.-");

1265

1971

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

1266

1972

/* Contains non-allowed characters */

1267

1973

if(debug){

1271

1977

return 0;

1272

1978

}

1273

1979

1274

char *fullname = NULL;

1275

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

1276

if(ret < 0){

1277

perror_plus("asprintf");

1278

return 0;

1279

}

1280

1281

ret = stat(fullname, &st);

1980

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

1282

1981

if(ret == -1){

1283

1982

if(debug){

1284

1983

perror_plus("Could not stat hook");

1301

2000

}

1302

2001

return 0;

1303

2002

}

2003

if(debug){

2004

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

2005

direntry->d_name);

2006

}

1304

2007

return 1;

1305

2008

}

1306

2009

1307

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2010

__attribute__((nonnull, warn_unused_result))

2011

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2012

mandos_context *mc){

1308

2013

int ret;

1309

2014

struct timespec now;

1310

2015

struct timespec waited_time;

1311

2016

intmax_t block_time;

1312

2017

1313

2018

while(true){

1314

if(mc.current_server == NULL){

1315

if (debug){

2019

if(mc->current_server == NULL){

2020

if(debug){

1316

2021

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

1317

2022

" No timeout!\n");

1318

2023

}

1319

2024

ret = avahi_simple_poll_iterate(s, -1);

1320

2025

} else {

1321

if (debug){

2026

if(debug){

1322

2027

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

1323

2028

" it, or wait\n");

1324

2029

}

1331

2036

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

1332

2037

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

1333

2038

waited_time.tv_sec = (now.tv_sec

1334

- mc.current_server->last_seen.tv_sec);

2039

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

1335

2040

waited_time.tv_nsec = (now.tv_nsec

1336

- mc.current_server->last_seen.tv_nsec);

2041

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

1337

2042

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

1338

2043

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

1339

2044

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

1341

2046

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

1342

2047

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

1343

2048

1344

if (debug){

2049

if(debug){

1345

2050

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

1346

2051

block_time);

1347

2052

}

1348

2053

1349

2054

if(block_time <= 0){

1350

ret = start_mandos_communication(mc.current_server->ip,

1351

mc.current_server->port,

1352

mc.current_server->if_index,

1353

mc.current_server->af);

2055

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

2056

mc->current_server->port,

2057

mc->current_server->if_index,

2058

mc->current_server->af, mc);

1354

2059

if(ret == 0){

1355

avahi_simple_poll_quit(mc.simple_poll);

2060

avahi_simple_poll_quit(s);

1356

2061

return 0;

1357

2062

}

1358

2063

ret = clock_gettime(CLOCK_MONOTONIC,

1359

&mc.current_server->last_seen);

2064

&mc->current_server->last_seen);

1360

2065

if(ret == -1){

1361

2066

perror_plus("clock_gettime");

1362

2067

return -1;

1363

2068

}

1364

mc.current_server = mc.current_server->next;

2069

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

1365

2070

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

1366

2071

servers, but don't block */

1367

2072

}

1369

2074

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

1370

2075

}

1371

2076

if(ret != 0){

1372

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

2077

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

1373

2078

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

1374

2079

}

1375

2080

}

1376

2081

}

1377

2082

}

1378

2083

1379

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

2084

__attribute__((nonnull))

2085

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

1380

2086

const float delay){

1381

struct dirent **direntries;

1382

struct dirent *direntry;

1383

int ret;

1384

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

1385

alphasort);

2087

struct dirent **direntries = NULL;

2088

if(hookdir_fd == -1){

2089

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2090

| O_CLOEXEC);

2091

if(hookdir_fd == -1){

2092

if(errno == ENOENT){

2093

if(debug){

2094

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

2095

" found\n", hookdir);

2096

}

2097

} else {

2098

perror_plus("open");

2099

}

2100

return;

2101

}

2102

}

2103

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

2104

if(devnull == -1){

2105

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

2106

return;

2107

}

2108

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

2109

runnable_hook, alphasort);

1386

2110

if(numhooks == -1){

1387

2111

perror_plus("scandir");

1388

} else {

1389

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

1390

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

1391

direntry = direntries[i];

1392

char *fullname = NULL;

1393

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

1394

if(ret < 0){

2112

close(devnull);

2113

return;

2114

}

2115

struct dirent *direntry;

2116

int ret;

2117

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

2118

direntry = direntries[i];

2119

if(debug){

2120

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

2121

direntry->d_name);

2122

}

2123

pid_t hook_pid = fork();

2124

if(hook_pid == 0){

2125

/* Child */

2126

/* Raise privileges */

2127

errno = raise_privileges_permanently();

2128

if(errno != 0){

2129

perror_plus("Failed to raise privileges");

2130

_exit(EX_NOPERM);

2131

}

2132

/* Set group */

2133

errno = 0;

2134

ret = setgid(0);

2135

if(ret == -1){

2136

perror_plus("setgid");

2137

_exit(EX_NOPERM);

2138

}

2139

/* Reset supplementary groups */

2140

errno = 0;

2141

ret = setgroups(0, NULL);

2142

if(ret == -1){

2143

perror_plus("setgroups");

2144

_exit(EX_NOPERM);

2145

}

2146

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

2147

if(ret == -1){

2148

perror_plus("setenv");

2149

_exit(EX_OSERR);

2150

}

2151

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

2152

if(ret == -1){

2153

perror_plus("setenv");

2154

_exit(EX_OSERR);

2155

}

2156

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

2157

if(ret == -1){

2158

perror_plus("setenv");

2159

_exit(EX_OSERR);

2160

}

2161

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

2162

if(ret == -1){

2163

perror_plus("setenv");

2164

_exit(EX_OSERR);

2165

}

2166

char *delaystring;

2167

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

2168

if(ret == -1){

1395

2169

perror_plus("asprintf");

1396

continue;

1397

}

1398

if(debug){

1399

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

1400

direntry->d_name);

1401

}

1402

pid_t hook_pid = fork();

1403

if(hook_pid == 0){

1404

/* Child */

1405

dup2(devnull, STDIN_FILENO);

1406

close(devnull);

1407

dup2(STDERR_FILENO, STDOUT_FILENO);

1408

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

1409

if(ret == -1){

1410

perror_plus("setenv");

1411

return false;

1412

}

1413

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

1414

if(ret == -1){

1415

perror_plus("setenv");

1416

return false;

1417

}

1418

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

1419

if(ret == -1){

1420

perror_plus("setenv");

1421

return false;

1422

}

1423

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

1424

if(ret == -1){

1425

perror_plus("setenv");

1426

return false;

1427

}

1428

char *delaystring;

1429

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

1430

if(ret == -1){

1431

perror_plus("asprintf");

1432

return false;

1433

}

1434

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

1435

if(ret == -1){

1436

free(delaystring);

1437

perror_plus("setenv");

1438

return false;

1439

}

2170

_exit(EX_OSERR);

2171

}

2172

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

2173

if(ret == -1){

1440

2174

free(delaystring);

1441

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

1442

perror_plus("execl");

1443

} else {

1444

int status;

1445

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

1446

perror_plus("waitpid");

1447

free(fullname);

1448

continue;

1449

}

1450

if(WIFEXITED(status)){

1451

if(WEXITSTATUS(status) != 0){

1452

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

1453

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

1454

WEXITSTATUS(status));

1455

free(fullname);

1456

continue;

1457

}

1458

} else if(WIFSIGNALED(status)){

1459

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

1460

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

1461

WTERMSIG(status));

1462

free(fullname);

1463

continue;

1464

} else {

1465

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

1466

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

1467

free(fullname);

1468

continue;

1469

}

1470

}

1471

free(fullname);

1472

if(quit_now){

1473

break;

1474

}

1475

}

1476

close(devnull);

1477

}

1478

return true;

2175

perror_plus("setenv");

2176

_exit(EX_OSERR);

2177

}

2178

free(delaystring);

2179

if(connect_to != NULL){

2180

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

2181

if(ret == -1){

2182

perror_plus("setenv");

2183

_exit(EX_OSERR);

2184

}

2185

}

2186

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

2187

direntry->d_name,

2188

O_RDONLY));

2189

if(hook_fd == -1){

2190

perror_plus("openat");

2191

_exit(EXIT_FAILURE);

2192

}

2193

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

2194

perror_plus("close");

2195

_exit(EXIT_FAILURE);

2196

}

2197

ret = dup2(devnull, STDIN_FILENO);

2198

if(ret == -1){

2199

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

2200

_exit(EX_OSERR);

2201

}

2202

ret = close(devnull);

2203

if(ret == -1){

2204

perror_plus("close");

2205

_exit(EX_OSERR);

2206

}

2207

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2208

if(ret == -1){

2209

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

2210

_exit(EX_OSERR);

2211

}

2212

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

2213

environ) == -1){

2214

perror_plus("fexecve");

2215

_exit(EXIT_FAILURE);

2216

}

2217

} else {

2218

if(hook_pid == -1){

2219

perror_plus("fork");

2220

free(direntry);

2221

continue;

2222

}

2223

int status;

2224

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

2225

perror_plus("waitpid");

2226

free(direntry);

2227

continue;

2228

}

2229

if(WIFEXITED(status)){

2230

if(WEXITSTATUS(status) != 0){

2231

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

2232

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

2233

WEXITSTATUS(status));

2234

free(direntry);

2235

continue;

2236

}

2237

} else if(WIFSIGNALED(status)){

2238

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

2239

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

2240

WTERMSIG(status));

2241

free(direntry);

2242

continue;

2243

} else {

2244

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

2245

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

2246

free(direntry);

2247

continue;

2248

}

2249

}

2250

if(debug){

2251

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

2252

direntry->d_name);

2253

}

2254

free(direntry);

2255

}

2256

free(direntries);

2257

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

2258

perror_plus("close");

2259

} else {

2260

hookdir_fd = -1;

2261

}

2262

close(devnull);

2263

}

2264

2265

__attribute__((nonnull, warn_unused_result))

2266

int bring_up_interface(const char *const interface,

2267

const float delay){

2268

int old_errno = errno;

2269

int ret;

2270

struct ifreq network;

2271

unsigned int if_index = if_nametoindex(interface);

2272

if(if_index == 0){

2273

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

2274

errno = old_errno;

2275

return ENXIO;

2276

}

2277

2278

if(quit_now){

2279

errno = old_errno;

2280

return EINTR;

2281

}

2282

2283

if(not interface_is_up(interface)){

2284

int ret_errno = 0;

2285

int ioctl_errno = 0;

2286

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

2287

ret_errno = errno;

2288

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

2289

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

2290

errno = old_errno;

2291

return ret_errno;

2292

}

2293

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

2294

2295

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

2296

if(sd == -1){

2297

ret_errno = errno;

2298

perror_plus("socket");

2299

errno = old_errno;

2300

return ret_errno;

2301

}

2302

2303

if(quit_now){

2304

ret = close(sd);

2305

if(ret == -1){

2306

perror_plus("close");

2307

}

2308

errno = old_errno;

2309

return EINTR;

2310

}

2311

2312

if(debug){

2313

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

2314

interface);

2315

}

2316

2317

/* Raise privileges */

2318

ret_errno = raise_privileges();

2319

if(ret_errno != 0){

2320

errno = ret_errno;

2321

perror_plus("Failed to raise privileges");

2322

}

2323

2324

#ifdef __linux__

2325

int ret_linux;

2326

bool restore_loglevel = false;

2327

if(ret_errno == 0){

2328

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2329

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

2330

ret_linux = klogctl(8, NULL, 5);

2331

if(ret_linux == -1){

2332

perror_plus("klogctl");

2333

} else {

2334

restore_loglevel = true;

2335

}

2336

}

2337

#endif /* __linux__ */

2338

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

2339

ioctl_errno = errno;

2340

#ifdef __linux__

2341

if(restore_loglevel){

2342

ret_linux = klogctl(7, NULL, 0);

2343

if(ret_linux == -1){

2344

perror_plus("klogctl");

2345

}

2346

}

2347

#endif /* __linux__ */

2348

2349

/* If raise_privileges() succeeded above */

2350

if(ret_errno == 0){

2351

/* Lower privileges */

2352

ret_errno = lower_privileges();

2353

if(ret_errno != 0){

2354

errno = ret_errno;

2355

perror_plus("Failed to lower privileges");

2356

}

2357

}

2358

2359

/* Close the socket */

2360

ret = close(sd);

2361

if(ret == -1){

2362

perror_plus("close");

2363

}

2364

2365

if(ret_setflags == -1){

2366

errno = ioctl_errno;

2367

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2368

errno = old_errno;

2369

return ioctl_errno;

2370

}

2371

} else if(debug){

2372

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

2373

interface);

2374

}

2375

2376

/* Sleep checking until interface is running.

2377

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

2378

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

2379

if(interface_is_running(interface)){

2380

break;

2381

}

2382

struct timespec sleeptime = { .tv_nsec = 250000000 };

2383

ret = nanosleep(&sleeptime, NULL);

2384

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

2385

perror_plus("nanosleep");

2386

}

2387

}

2388

2389

errno = old_errno;

2390

return 0;

2391

}

2392

2393

__attribute__((nonnull, warn_unused_result))

2394

int take_down_interface(const char *const interface){

2395

int old_errno = errno;

2396

struct ifreq network;

2397

unsigned int if_index = if_nametoindex(interface);

2398

if(if_index == 0){

2399

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

2400

errno = old_errno;

2401

return ENXIO;

2402

}

2403

if(interface_is_up(interface)){

2404

int ret_errno = 0;

2405

int ioctl_errno = 0;

2406

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

2407

ret_errno = errno;

2408

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

2409

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

2410

errno = old_errno;

2411

return ret_errno;

2412

}

2413

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

2414

2415

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

2416

if(sd == -1){

2417

ret_errno = errno;

2418

perror_plus("socket");

2419

errno = old_errno;

2420

return ret_errno;

2421

}

2422

2423

if(debug){

2424

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

2425

interface);

2426

}

2427

2428

/* Raise privileges */

2429

ret_errno = raise_privileges();

2430

if(ret_errno != 0){

2431

errno = ret_errno;

2432

perror_plus("Failed to raise privileges");

2433

}

2434

2435

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

2436

ioctl_errno = errno;

2437

2438

/* If raise_privileges() succeeded above */

2439

if(ret_errno == 0){

2440

/* Lower privileges */

2441

ret_errno = lower_privileges();

2442

if(ret_errno != 0){

2443

errno = ret_errno;

2444

perror_plus("Failed to lower privileges");

2445

}

2446

}

2447

2448

/* Close the socket */

2449

int ret = close(sd);

2450

if(ret == -1){

2451

perror_plus("close");

2452

}

2453

2454

if(ret_setflags == -1){

2455

errno = ioctl_errno;

2456

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2457

errno = old_errno;

2458

return ioctl_errno;

2459

}

2460

} else if(debug){

2461

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

2462

interface);

2463

}

2464

2465

errno = old_errno;

2466

return 0;

1479

2467

}

1480

2468

1481

2469

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

2470

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

2471

#if GNUTLS_VERSION_NUMBER >= 0x030606

2472

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

2473

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

2474

":%PROFILE_ULTRA",

2475

#elif GNUTLS_VERSION_NUMBER < 0x030600

2476

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

2477

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

2478

#else

2479

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

2480

#endif

2481

.current_server = NULL, .interfaces = NULL,

2482

.interfaces_size = 0 };

1482

2483

AvahiSServiceBrowser *sb = NULL;

1483

int error;

2484

error_t ret_errno;

1484

2485

int ret;

1485

2486

intmax_t tmpmax;

1486

2487

char *tmp;

1487

2488

int exitcode = EXIT_SUCCESS;

1488

const char *interface = "";

1489

struct ifreq network;

1490

int sd = -1;

1491

bool take_down_interface = false;

1492

uid_t uid;

1493

gid_t gid;

1494

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

1495

bool tempdir_created = false;

2489

char *interfaces_to_take_down = NULL;

2490

size_t interfaces_to_take_down_size = 0;

2491

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

2492

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

2493

char *tempdir = NULL;

1496

2494

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

1497

2495

const char *seckey = PATHDIR "/" SECKEY;

1498

2496

const char *pubkey = PATHDIR "/" PUBKEY;

2497

#if GNUTLS_VERSION_NUMBER >= 0x030606

2498

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2499

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2500

#endif

2501

const char *dh_params_file = NULL;

2502

char *interfaces_hooks = NULL;

1499

2503

1500

2504

bool gnutls_initialized = false;

1501

2505

bool gpgme_initialized = false;

1547

2551

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

1548

2552

.arg = "FILE",

1549

2553

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

1550

.group = 2 },

2554

.group = 1 },

2555

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

2556

.arg = "FILE",

2557

#if GNUTLS_VERSION_NUMBER >= 0x030606

2558

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

2559

#else

2560

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

2561

#endif

2562

.group = 1 },

2563

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

2564

.arg = "FILE",

2565

#if GNUTLS_VERSION_NUMBER >= 0x030606

2566

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

2567

#else

2568

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

2569

#endif

2570

.group = 1 },

1551

2571

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

1552

2572

.arg = "BITS",

1553

2573

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

1554

2574

" Diffie-Hellman key exchange",

1555

2575

.group = 2 },

2576

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

2577

.arg = "FILE",

2578

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

2579

" for the Diffie-Hellman key exchange",

2580

.group = 2 },

1556

2581

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

1557

2582

.arg = "STRING",

1558

2583

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

1563

2588

.group = 2 },

1564

2589

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

1565

2590

.arg = "SECONDS",

1566

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

2591

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

1567

2592

.group = 2 },

1568

2593

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

1569

2594

.arg = "DIR",

1592

2617

connect_to = arg;

1593

2618

break;

1594

2619

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

1595

interface = arg;

2620

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

2621

arg, (int)',');

2622

if(ret_errno != 0){

2623

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

2624

}

1596

2625

break;

1597

2626

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

1598

2627

seckey = arg;

1600

2629

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

1601

2630

pubkey = arg;

1602

2631

break;

2632

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

2633

#if GNUTLS_VERSION_NUMBER >= 0x030606

2634

tls_privkey = arg;

2635

#endif

2636

break;

2637

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

2638

#if GNUTLS_VERSION_NUMBER >= 0x030606

2639

tls_pubkey = arg;

2640

#endif

2641

break;

1603

2642

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

1604

2643

errno = 0;

1605

2644

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

1609

2648

}

1610

2649

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

1611

2650

break;

2651

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

2652

dh_params_file = arg;

2653

break;

1612

2654

case 130: /* --priority */

1613

2655

mc.priority = arg;

1614

2656

break;

1637

2679

argp_state_help(state, state->out_stream,

1638

2680

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

1639

2681

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2682

__builtin_unreachable();

1640

2683

case -3: /* --usage */

1641

2684

argp_state_help(state, state->out_stream,

1642

2685

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2686

__builtin_unreachable();

1643

2687

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

1644

fprintf_plus(state->out_stream,

1645

"Mandos plugin mandos-client: ");

1646

2688

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

1647

2689

exit(argp_err_exit_status);

1648

2690

break;

1656

2698

.args_doc = "",

1657

2699

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

1658

2700

" passwords from a Mandos server" };

1659

ret = argp_parse(&argp, argc, argv,

1660

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1661

switch(ret){

2701

ret_errno = argp_parse(&argp, argc, argv,

2702

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2703

switch(ret_errno){

1662

2704

case 0:

1663

2705

break;

1664

2706

case ENOMEM:

1665

2707

default:

1666

errno = ret;

2708

errno = ret_errno;

1667

2709

perror_plus("argp_parse");

1668

2710

exitcode = EX_OSERR;

1669

2711

goto end;

1672

2714

goto end;

1673

2715

}

1674

2716

}

1675

1676

if(getuid() == 0){

2717

2718

{

1677

2719

/* Work around Debian bug #633582:

1678

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

1679

struct stat st;

1680

1681

/* Re-raise priviliges */

1682

errno = 0;

1683

ret = seteuid(0);

1684

if(ret == -1){

1685

perror_plus("seteuid");

1686

}

1687

1688

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

1689

int seckey_fd = open(seckey, O_RDONLY);

1690

if(seckey_fd == -1){

1691

perror_plus("open");

1692

} else {

1693

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

1694

if(ret == -1){

1695

perror_plus("fstat");

1696

} else {

1697

if(S_ISREG(st.st_mode)

1698

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

1699

ret = fchown(seckey_fd, uid, gid);

1700

if(ret == -1){

1701

perror_plus("fchown");

1702

}

1703

}

1704

}

1705

TEMP_FAILURE_RETRY(close(seckey_fd));

1706

}

1707

}

1708

1709

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

1710

int pubkey_fd = open(pubkey, O_RDONLY);

1711

if(pubkey_fd == -1){

1712

perror_plus("open");

1713

} else {

1714

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

1715

if(ret == -1){

1716

perror_plus("fstat");

1717

} else {

1718

if(S_ISREG(st.st_mode)

1719

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

1720

ret = fchown(pubkey_fd, uid, gid);

1721

if(ret == -1){

1722

perror_plus("fchown");

1723

}

1724

}

1725

}

1726

TEMP_FAILURE_RETRY(close(pubkey_fd));

1727

}

1728

}

1729

1730

/* Lower privileges */

1731

errno = 0;

1732

ret = seteuid(uid);

1733

if(ret == -1){

1734

perror_plus("seteuid");

2720

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

2721

2722

/* Re-raise privileges */

2723

ret = raise_privileges();

2724

if(ret != 0){

2725

errno = ret;

2726

perror_plus("Failed to raise privileges");

2727

} else {

2728

struct stat st;

2729

2730

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

2731

int seckey_fd = open(seckey, O_RDONLY);

2732

if(seckey_fd == -1){

2733

perror_plus("open");

2734

} else {

2735

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

2736

if(ret == -1){

2737

perror_plus("fstat");

2738

} else {

2739

if(S_ISREG(st.st_mode)

2740

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

2741

ret = fchown(seckey_fd, uid, gid);

2742

if(ret == -1){

2743

perror_plus("fchown");

2744

}

2745

}

2746

}

2747

close(seckey_fd);

2748

}

2749

}

2750

2751

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

2752

int pubkey_fd = open(pubkey, O_RDONLY);

2753

if(pubkey_fd == -1){

2754

perror_plus("open");

2755

} else {

2756

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

2757

if(ret == -1){

2758

perror_plus("fstat");

2759

} else {

2760

if(S_ISREG(st.st_mode)

2761

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

2762

ret = fchown(pubkey_fd, uid, gid);

2763

if(ret == -1){

2764

perror_plus("fchown");

2765

}

2766

}

2767

}

2768

close(pubkey_fd);

2769

}

2770

}

2771

2772

if(dh_params_file != NULL

2773

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

2774

int dhparams_fd = open(dh_params_file, O_RDONLY);

2775

if(dhparams_fd == -1){

2776

perror_plus("open");

2777

} else {

2778

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

2779

if(ret == -1){

2780

perror_plus("fstat");

2781

} else {

2782

if(S_ISREG(st.st_mode)

2783

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

2784

ret = fchown(dhparams_fd, uid, gid);

2785

if(ret == -1){

2786

perror_plus("fchown");

2787

}

2788

}

2789

}

2790

close(dhparams_fd);

2791

}

2792

}

2793

2794

/* Lower privileges */

2795

ret = lower_privileges();

2796

if(ret != 0){

2797

errno = ret;

2798

perror_plus("Failed to lower privileges");

2799

}

2800

}

2801

}

2802

2803

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

2804

{

2805

char *interface = NULL;

2806

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

2807

interface))){

2808

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

2809

and if_nametoindex(interface) == 0){

2810

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

2811

fprintf_plus(stderr, "Not using nonexisting interface"

2812

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

2813

}

2814

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

2815

interface = NULL;

2816

}

1735

2817

}

1736

2818

}

1737

2819

1738

2820

/* Run network hooks */

1739

2821

{

1740

if(getuid() == 0){

1741

/* Re-raise priviliges */

1742

errno = 0;

1743

ret = seteuid(0);

1744

if(ret == -1){

1745

perror_plus("seteuid");

1746

}

1747

}

1748

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

1749

goto end;

1750

}

1751

if(getuid() == 0){

1752

/* Lower privileges */

1753

errno = 0;

1754

ret = seteuid(uid);

1755

if(ret == -1){

1756

perror_plus("seteuid");

1757

}

1758

}

2822

if(mc.interfaces != NULL){

2823

interfaces_hooks = malloc(mc.interfaces_size);

2824

if(interfaces_hooks == NULL){

2825

perror_plus("malloc");

2826

goto end;

2827

}

2828

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

2829

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

2830

}

2831

run_network_hooks("start", interfaces_hooks != NULL ?

2832

interfaces_hooks : "", delay);

1759

2833

}

1760

2834

1761

2835

if(not debug){

1762

2836

avahi_set_log_function(empty_log);

1763

2837

}

1764

2838

1765

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

1766

struct dirent **direntries;

1767

/* First look for interfaces that are up */

1768

ret = scandir(sys_class_net, &direntries, up_interface,

1769

alphasort);

1770

if(ret == 0){

1771

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

1772

free(direntries);

1773

ret = scandir(sys_class_net, &direntries, good_interface,

1774

alphasort);

1775

}

1776

if(ret >= 1){

1777

/* Pick the first interface returned */

1778

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

1779

if(debug){

1780

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

1781

}

1782

if(interface == NULL){

1783

perror_plus("malloc");

1784

free(direntries);

1785

exitcode = EXIT_FAILURE;

1786

goto end;

1787

}

1788

free(direntries);

1789

} else {

1790

free(direntries);

1791

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

1792

exitcode = EXIT_FAILURE;

1793

goto end;

1794

}

1795

}

1796

1797

2839

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

1798

2840

from the signal handler */

1799

2841

/* Initialize the pseudo-RNG for Avahi */

1800

2842

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

1801

mc.simple_poll = avahi_simple_poll_new();

1802

if(mc.simple_poll == NULL){

2843

simple_poll = avahi_simple_poll_new();

2844

if(simple_poll == NULL){

1803

2845

fprintf_plus(stderr,

1804

2846

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

1805

2847

exitcode = EX_UNAVAILABLE;

1869

2911

}

1870

2912

}

1871

2913

1872

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

1873

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

1874

if_index = (AvahiIfIndex) if_nametoindex(interface);

1875

if(if_index == 0){

1876

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

1877

exitcode = EX_UNAVAILABLE;

1878

goto end;

1879

}

1880

1881

if(quit_now){

1882

goto end;

1883

}

1884

1885

/* Re-raise priviliges */

1886

errno = 0;

1887

ret = seteuid(0);

1888

if(ret == -1){

1889

perror_plus("seteuid");

1890

}

1891

1892

#ifdef __linux__

1893

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1894

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

1895

ret = klogctl(8, NULL, 5);

1896

bool restore_loglevel = true;

1897

if(ret == -1){

1898

restore_loglevel = false;

1899

perror_plus("klogctl");

1900

}

1901

#endif /* __linux__ */

1902

1903

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1904

if(sd < 0){

1905

perror_plus("socket");

1906

exitcode = EX_OSERR;

1907

#ifdef __linux__

1908

if(restore_loglevel){

1909

ret = klogctl(7, NULL, 0);

1910

if(ret == -1){

1911

perror_plus("klogctl");

1912

}

1913

}

1914

#endif /* __linux__ */

1915

/* Lower privileges */

1916

errno = 0;

1917

ret = seteuid(uid);

1918

if(ret == -1){

1919

perror_plus("seteuid");

1920

}

1921

goto end;

1922

}

1923

strcpy(network.ifr_name, interface);

1924

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

1925

if(ret == -1){

1926

perror_plus("ioctl SIOCGIFFLAGS");

1927

#ifdef __linux__

1928

if(restore_loglevel){

1929

ret = klogctl(7, NULL, 0);

1930

if(ret == -1){

1931

perror_plus("klogctl");

1932

}

1933

}

1934

#endif /* __linux__ */

1935

exitcode = EX_OSERR;

1936

/* Lower privileges */

1937

errno = 0;

1938

ret = seteuid(uid);

1939

if(ret == -1){

1940

perror_plus("seteuid");

1941

}

1942

goto end;

1943

}

1944

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

1945

network.ifr_flags |= IFF_UP;

1946

take_down_interface = true;

1947

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

1948

if(ret == -1){

1949

take_down_interface = false;

1950

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1951

exitcode = EX_OSERR;

1952

#ifdef __linux__

1953

if(restore_loglevel){

1954

ret = klogctl(7, NULL, 0);

1955

if(ret == -1){

1956

perror_plus("klogctl");

2914

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

2915

if(mc.interfaces == NULL){

2916

struct dirent **direntries = NULL;

2917

/* Look for any good interfaces */

2918

ret = scandir(sys_class_net, &direntries, good_interface,

2919

alphasort);

2920

if(ret >= 1){

2921

/* Add all found interfaces to interfaces list */

2922

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

2923

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

2924

direntries[i]->d_name);

2925

if(ret_errno != 0){

2926

errno = ret_errno;

2927

perror_plus("argz_add");

2928

free(direntries[i]);

2929

continue;

2930

}

2931

if(debug){

2932

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

2933

direntries[i]->d_name);

2934

}

2935

free(direntries[i]);

2936

}

2937

free(direntries);

2938

} else {

2939

if(ret == 0){

2940

free(direntries);

2941

}

2942

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

2943

exitcode = EXIT_FAILURE;

2944

goto end;

2945

}

2946

}

2947

2948

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

2949

{

2950

char *interface = NULL;

2951

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

2952

interface))){

2953

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

2954

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

2955

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

2956

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

2957

interface);

2958

interface = NULL;

2959

while((interface = argz_next(mc.interfaces,

2960

mc.interfaces_size, interface))){

2961

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

2962

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

2963

interface);

2964

interface = NULL;

1957

2965

}

1958

2966

}

1959

#endif /* __linux__ */

1960

/* Lower privileges */

1961

errno = 0;

1962

ret = seteuid(uid);

1963

if(ret == -1){

1964

perror_plus("seteuid");

1965

}

1966

goto end;

1967

}

1968

}

1969

/* Sleep checking until interface is running.

1970

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

1971

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

1972

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

1973

if(ret == -1){

1974

perror_plus("ioctl SIOCGIFFLAGS");

1975

} else if(network.ifr_flags & IFF_RUNNING){

1976

2967

break;

1977

2968

}

1978

struct timespec sleeptime = { .tv_nsec = 250000000 };

1979

ret = nanosleep(&sleeptime, NULL);

1980

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

1981

perror_plus("nanosleep");

1982

}

1983

}

1984

if(not take_down_interface){

1985

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

1986

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

1987

if(ret == -1){

1988

perror_plus("close");

1989

}

1990

}

1991

#ifdef __linux__

1992

if(restore_loglevel){

1993

/* Restores kernel loglevel to default */

1994

ret = klogctl(7, NULL, 0);

1995

if(ret == -1){

1996

perror_plus("klogctl");

1997

}

1998

}

1999

#endif /* __linux__ */

2000

/* Lower privileges */

2001

errno = 0;

2002

/* Lower privileges */

2003

ret = seteuid(uid);

2004

if(ret == -1){

2005

perror_plus("seteuid");

2006

}

2969

bool interface_was_up = interface_is_up(interface);

2970

errno = bring_up_interface(interface, delay);

2971

if(not interface_was_up){

2972

if(errno != 0){

2973

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

2974

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

2975

} else {

2976

errno = argz_add(&interfaces_to_take_down,

2977

&interfaces_to_take_down_size,

2978

interface);

2979

if(errno != 0){

2980

perror_plus("argz_add");

2981

}

2982

}

2983

}

2984

}

2985

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

2986

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

2987

}

2988

}

2989

2990

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

2991

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

2992

if(debug){

2993

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

2994

mc.interfaces);

2995

}

2996

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

2007

2997

}

2008

2998

2009

2999

if(quit_now){

2010

3000

goto end;

2011

3001

}

2012

3002

2013

ret = init_gnutls_global(pubkey, seckey);

3003

#if GNUTLS_VERSION_NUMBER >= 0x030606

3004

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

3005

#elif GNUTLS_VERSION_NUMBER < 0x030600

3006

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

3007

#else

3008

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

3009

#endif

2014

3010

if(ret == -1){

2015

3011

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

2016

3012

exitcode = EX_UNAVAILABLE;

2023

3019

goto end;

2024

3020

}

2025

3021

2026

if(mkdtemp(tempdir) == NULL){

3022

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

3023

tempdir = mkdtemp(run_tempdir);

3024

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

3025

if(debug){

3026

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

3027

run_tempdir, old_tempdir);

3028

}

3029

tempdir = mkdtemp(old_tempdir);

3030

}

3031

if(tempdir == NULL){

2027

3032

perror_plus("mkdtemp");

2028

3033

goto end;

2029

3034

}

2030

tempdir_created = true;

2031

3035

2032

3036

if(quit_now){

2033

3037

goto end;

2034

3038

}

2035

3039

2036

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

3040

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

2037

3041

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

2038

3042

exitcode = EX_UNAVAILABLE;

2039

3043

goto end;

2049

3053

/* Connect directly, do not use Zeroconf */

2050

3054

/* (Mainly meant for debugging) */

2051

3055

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

3056

2052

3057

if(address == NULL){

2053

3058

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

2054

3059

exitcode = EX_USAGE;

2059

3064

goto end;

2060

3065

}

2061

3066

2062

uint16_t port;

3067

in_port_t port;

2063

3068

errno = 0;

2064

3069

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

2065

3070

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

2066

or tmpmax != (uint16_t)tmpmax){

3071

or tmpmax != (in_port_t)tmpmax){

2067

3072

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

2068

3073

exitcode = EX_USAGE;

2069

3074

goto end;

2070

3075

}

2071

3076

2072

3077

if(quit_now){

2073

3078

goto end;

2074

3079

}

2075

3080

2076

port = (uint16_t)tmpmax;

3081

port = (in_port_t)tmpmax;

2077

3082

*address = '\0';

2078

3083

/* Colon in address indicates IPv6 */

2079

3084

int af;

2095

3100

}

2096

3101

2097

3102

while(not quit_now){

2098

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

3103

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

3104

&mc);

2099

3105

if(quit_now or ret == 0){

2100

3106

break;

2101

3107

}

2103

3109

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

2104

3110

(int)retry_interval);

2105

3111

}

2106

sleep((int)retry_interval);

3112

sleep((unsigned int)retry_interval);

2107

3113

}

2108

3114

2109

if (not quit_now){

3115

if(not quit_now){

2110

3116

exitcode = EXIT_SUCCESS;

2111

3117

}

2112

3118

2127

3133

config.publish_domain = 0;

2128

3134

2129

3135

/* Allocate a new server */

2130

mc.server = avahi_server_new(avahi_simple_poll_get

2131

(mc.simple_poll), &config, NULL,

2132

NULL, &error);

3136

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3137

&config, NULL, NULL, &ret);

2133

3138

2134

3139

/* Free the Avahi configuration data */

2135

3140

avahi_server_config_free(&config);

2138

3143

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

2139

3144

if(mc.server == NULL){

2140

3145

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

2141

avahi_strerror(error));

3146

avahi_strerror(ret));

2142

3147

exitcode = EX_UNAVAILABLE;

2143

3148

goto end;

2144

3149

}

2150

3155

/* Create the Avahi service browser */

2151

3156

sb = avahi_s_service_browser_new(mc.server, if_index,

2152

3157

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

2153

NULL, 0, browse_callback, NULL);

3158

NULL, 0, browse_callback,

3159

(void *)&mc);

2154

3160

if(sb == NULL){

2155

3161

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

2156

3162

avahi_strerror(avahi_server_errno(mc.server)));

2167

3173

if(debug){

2168

3174

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

2169

3175

}

2170

2171

ret = avahi_loop_with_timeout(mc.simple_poll,

2172

(int)(retry_interval * 1000));

3176

3177

ret = avahi_loop_with_timeout(simple_poll,

3178

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

2173

3179

if(debug){

2174

3180

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

2175

3181

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

2178

3184

end:

2179

3185

2180

3186

if(debug){

2181

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

3187

if(signal_received){

3188

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

3189

argv[0], signal_received,

3190

strsignal(signal_received));

3191

} else {

3192

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

3193

}

2182

3194

}

2183

3195

2184

3196

/* Cleanup things */

3197

free(mc.interfaces);

3198

2185

3199

if(sb != NULL)

2186

3200

avahi_s_service_browser_free(sb);

2187

3201

2188

3202

if(mc.server != NULL)

2189

3203

avahi_server_free(mc.server);

2190

3204

2191

if(mc.simple_poll != NULL)

2192

avahi_simple_poll_free(mc.simple_poll);

3205

if(simple_poll != NULL)

3206

avahi_simple_poll_free(simple_poll);

2193

3207

2194

3208

if(gnutls_initialized){

2195

3209

gnutls_certificate_free_credentials(mc.cred);

2196

gnutls_global_deinit();

2197

3210

gnutls_dh_params_deinit(mc.dh_params);

2198

3211

}

2199

3212

2200

3213

if(gpgme_initialized){

2201

3214

gpgme_release(mc.ctx);

2202

3215

}

2203

3216

2204

3217

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

2205

3218

has seen */

2206

3219

if(mc.current_server != NULL){

2207

3220

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

2208

3221

while(mc.current_server != NULL){

2209

3222

server *next = mc.current_server->next;

3223

#ifdef __GNUC__

3224

#pragma GCC diagnostic push

3225

#pragma GCC diagnostic ignored "-Wcast-qual"

3226

#endif

3227

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

3228

#ifdef __GNUC__

3229

#pragma GCC diagnostic pop

3230

#endif

2210

3231

free(mc.current_server);

2211

3232

mc.current_server = next;

2212

3233

}

2213

3234

}

2214

3235

2215

/* Re-raise priviliges */

3236

/* Re-raise privileges */

2216

3237

{

2217

if(getuid() == 0){

2218

errno = 0;

2219

ret = seteuid(0);

2220

if(ret == -1){

2221

perror_plus("seteuid");

3238

ret = raise_privileges();

3239

if(ret != 0){

3240

errno = ret;

3241

perror_plus("Failed to raise privileges");

3242

} else {

3243

3244

/* Run network hooks */

3245

run_network_hooks("stop", interfaces_hooks != NULL ?

3246

interfaces_hooks : "", delay);

3247

3248

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

3249

{

3250

char *interface = NULL;

3251

while((interface = argz_next(interfaces_to_take_down,

3252

interfaces_to_take_down_size,

3253

interface))){

3254

ret = take_down_interface(interface);

3255

if(ret != 0){

3256

errno = ret;

3257

perror_plus("Failed to take down interface");

3258

}

3259

}

3260

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

3261

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

3262

" down\n");

3263

}

2222

3264

}

2223

3265

}

2224

/* Run network hooks */

2225

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

2226

goto end;

2227

}

2228

3266

2229

/* Take down the network interface */

2230

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

2231

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

2232

if(ret == -1){

2233

perror_plus("ioctl SIOCGIFFLAGS");

2234

} else if(network.ifr_flags & IFF_UP){

2235

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

2236

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

2237

if(ret == -1){

2238

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2239

}

2240

}

2241

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

2242

if(ret == -1){

2243

perror_plus("close");

2244

}

3267

ret = lower_privileges_permanently();

3268

if(ret != 0){

3269

errno = ret;

3270

perror_plus("Failed to lower privileges permanently");

2245

3271

}

2246

3272

}

2247

if(getuid() == 0){

2248

/* Lower privileges permanently */

2249

errno = 0;

2250

ret = setuid(uid);

2251

if(ret == -1){

2252

perror_plus("setuid");

2253

}

3273

3274

free(interfaces_to_take_down);

3275

free(interfaces_hooks);

3276

3277

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

3278

uintmax_t level){

3279

struct dirent **direntries = NULL;

3280

int dret;

3281

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

3282

O_RDONLY

3283

| O_NOFOLLOW

3284

| O_DIRECTORY

3285

| O_PATH));

3286

if(dir_fd == -1){

3287

perror_plus("open");

3288

return;

3289

}

3290

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

3291

notdotentries, alphasort);

3292

if(numentries >= 0){

3293

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

3294

if(debug){

3295

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

3296

dirname, direntries[i]->d_name);

3297

}

3298

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

3299

if(dret == -1){

3300

if(errno == EISDIR){

3301

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

3302

AT_REMOVEDIR);

3303

}

3304

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

3305

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

3306

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

3307

/* Recurse only in this special case */

3308

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

3309

dret = 0;

3310

}

3311

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

3312

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

3313

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

3314

}

3315

}

3316

free(direntries[i]);

3317

}

3318

3319

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

3320

free(direntries);

3321

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3322

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

3323

perror_plus("rmdir");

3324

}

3325

} else {

3326

perror_plus("scandirat");

3327

}

3328

close(dir_fd);

2254

3329

}

2255

3330

2256

3331

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

2257

if(tempdir_created){

2258

struct dirent **direntries = NULL;

2259

struct dirent *direntry = NULL;

2260

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

2261

alphasort);

2262

if (numentries > 0){

2263

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

2264

direntry = direntries[i];

2265

char *fullname = NULL;

2266

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

2267

direntry->d_name);

2268

if(ret < 0){

2269

perror_plus("asprintf");

2270

continue;

2271

}

2272

ret = remove(fullname);

2273

if(ret == -1){

2274

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

2275

strerror(errno));

2276

}

2277

free(fullname);

2278

}

2279

}

2280

2281

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

2282

free(direntries);

2283

if (numentries == -1){

2284

perror_plus("scandir");

2285

}

2286

ret = rmdir(tempdir);

2287

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

2288

perror_plus("rmdir");

2289

}

3332

if(tempdir != NULL){

3333

clean_dir_at(-1, tempdir, 0);

2290

3334

}

2291

3335

2292

3336

if(quit_now){