/mandos/release : revision 237.16.14

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

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*

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* Everything else is

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*

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* This file is part of Mandos.

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*

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

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

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

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* (at your option) any later version.

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*

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

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*

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

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

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

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

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*

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

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* WITHOUT ANY WARRANTY; without even the implied warranty of

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

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* General Public License for more details.

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*

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

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

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* along with this program. If not, see

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

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*

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

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*/

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

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#ifndef _LARGEFILE_SOURCE

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#define _LARGEFILE_SOURCE

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#endif /* not _LARGEFILE_SOURCE */

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#endif

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#ifndef _FILE_OFFSET_BITS

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#define _FILE_OFFSET_BITS 64

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#endif /* not _FILE_OFFSET_BITS */

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#endif

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

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

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stdout, ferror() */

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

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stdout, ferror(), remove() */

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

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

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

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strtof(), abort() */

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

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

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asprintf(), strncpy(), strsignal()

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*/

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

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

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

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

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sockaddr_in6, PF_INET6,

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opendir(), DIR */

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

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

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inet_pton(), connect(),

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getnameinfo() */

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

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inet_pton(), connect() */

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

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

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*/

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

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strtoimax() */

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

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EAI_SYSTEM, ENETUNREACH,

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EHOSTUNREACH, ECONNREFUSED, EPROTO,

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EIO, ENOENT, ENXIO, ENOMEM, EISDIR,

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ENOTEMPTY,

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

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

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program_invocation_short_name */

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

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

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*/

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

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

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

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unlinkat(), lstat(), symlink() */

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

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setgid(), pause() */

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

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

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

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argp_state, struct argp,

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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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in_port_t port;

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uint16_t port;

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AvahiIfIndex if_index;

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int af;

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struct timespec last_seen;

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

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typedef struct {

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AvahiSimplePoll *simple_poll;

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AvahiServer *server;

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gnutls_certificate_credentials_t cred;

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unsigned int dh_bits;

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const char *priority;

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gpgme_ctx_t ctx;

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server *current_server;

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char *interfaces;

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size_t interfaces_size;

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} mandos_context;

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/* global so signal handler can reach it*/

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AvahiSimplePoll *simple_poll;

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

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

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.dh_bits = 1024, .priority = "SECURE256"

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

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.current_server = NULL };

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sig_atomic_t quit_now = 0;

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int signal_received = 0;

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/* Function to use when printing errors */

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void perror_plus(const char *print_text){

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int e = errno;

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

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program_invocation_short_name);

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errno = e;

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perror(print_text);

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}

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

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

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va_list ap;

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va_start (ap, format);

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

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program_invocation_short_name));

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

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

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}

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/*

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

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* "buffer_length" is how much is already used.

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*/

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__attribute__((nonnull, warn_unused_result))

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size_t incbuffer(char **buffer, size_t buffer_length,

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size_t buffer_capacity){

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if(buffer_length + BUFFER_SIZE > buffer_capacity){

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

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if(new_buf == NULL){

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int old_errno = errno;

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free(*buffer);

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errno = old_errno;

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*buffer = NULL;

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

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if(buffer == NULL){

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return 0;

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}

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*buffer = new_buf;

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buffer_capacity += BUFFER_SIZE;

231

199

}

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return buffer_capacity;

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}

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

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__attribute__((nonnull, warn_unused_result))

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

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int af, server **current_server){

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

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int af){

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int ret;

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

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if(new_server == NULL){

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perror_plus("malloc");

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return false;

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return -1;

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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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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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return -1;

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}

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/* Special case of first server */

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if(*current_server == NULL){

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if (mc.current_server == NULL){

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new_server->next = new_server;

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new_server->prev = new_server;

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*current_server = new_server;

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mc.current_server = new_server;

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

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} else {

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

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new_server->next = *current_server;

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

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new_server->next = mc.current_server;

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

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new_server->prev->next = new_server;

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(*current_server)->prev = new_server;

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}

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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;

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int ret = 0;

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

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ret = errno;

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}

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errno = old_errno;

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return ret;

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}

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

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__attribute__((warn_unused_result))

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int raise_privileges_permanently(void){

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int old_errno = errno;

299

int ret = raise_privileges();

300

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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}

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errno = old_errno;

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return ret;

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}

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

312

__attribute__((warn_unused_result))

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int lower_privileges(void){

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int old_errno = errno;

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int ret = 0;

316

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

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ret = errno;

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}

319

errno = old_errno;

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return ret;

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}

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/* Lower privileges permanently */

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__attribute__((warn_unused_result))

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int lower_privileges_permanently(void){

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int old_errno = errno;

327

int ret = 0;

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

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ret = errno;

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}

331

errno = old_errno;

332

return ret;

230

mc.current_server->prev = new_server;

231

}

232

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

233

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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}

334

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335

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/*

336

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* Initialize GPGME.

337

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*/

338

__attribute__((nonnull, warn_unused_result))

339

static bool init_gpgme(const char * const seckey,

340

const char * const pubkey,

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const char * const tempdir,

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mandos_context *mc){

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

244

const char *tempdir){

343

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gpgme_error_t rc;

344

246

gpgme_engine_info_t engine_info;

345

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248

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/*

347

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

348

251

*/

349

bool import_key(const char * const filename){

252

bool import_key(const char *filename){

350

253

int ret;

351

254

int fd;

352

255

gpgme_data_t pgp_data;

357

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return false;

358

261

}

359

262

360

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

361

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

362

do {

363

{

364

time_t currtime = time(NULL);

365

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

366

struct tm tm;

367

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

368

perror_plus("gmtime_r");

369

break;

370

}

371

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

372

break;

373

}

374

if(debug){

375

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

376

}

377

} else {

378

if(debug){

379

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

380

}

381

}

382

}

383

struct stat keystat;

384

ret = fstat(fd, &keystat);

385

if(ret != 0){

386

perror_plus("fstat");

387

break;

388

}

389

ret = raise_privileges();

390

if(ret != 0){

391

errno = ret;

392

perror_plus("Failed to raise privileges");

393

break;

394

}

395

if(debug){

396

fprintf_plus(stderr,

397

"Setting system clock to key file mtime");

398

}

399

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

400

perror_plus("clock_settime");

401

}

402

ret = lower_privileges();

403

if(ret != 0){

404

errno = ret;

405

perror_plus("Failed to lower privileges");

406

}

407

} while(false);

408

409

263

rc = gpgme_data_new_from_fd(&pgp_data, fd);

410

264

if(rc != GPG_ERR_NO_ERROR){

411

265

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

413

267

return false;

414

268

}

415

269

416

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

270

rc = gpgme_op_import(mc.ctx, pgp_data);

417

271

if(rc != GPG_ERR_NO_ERROR){

418

272

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

419

273

gpgme_strsource(rc), gpgme_strerror(rc));

420

274

return false;

421

275

}

422

{

423

gpgme_import_result_t import_result

424

= gpgme_op_import_result(mc->ctx);

425

if((import_result->imported < 1

426

or import_result->not_imported > 0)

427

and import_result->unchanged == 0){

428

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

429

fprintf_plus(stderr,

430

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

431

import_result->considered);

432

fprintf_plus(stderr,

433

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

434

import_result->no_user_id);

435

fprintf_plus(stderr,

436

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

437

import_result->imported);

438

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

439

import_result->imported_rsa);

440

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

441

import_result->unchanged);

442

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

443

import_result->new_user_ids);

444

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

445

import_result->new_sub_keys);

446

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

447

import_result->new_signatures);

448

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

449

import_result->new_revocations);

450

fprintf_plus(stderr,

451

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

452

import_result->secret_read);

453

fprintf_plus(stderr,

454

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

455

import_result->secret_imported);

456

fprintf_plus(stderr,

457

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

458

import_result->secret_unchanged);

459

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

460

import_result->not_imported);

461

for(gpgme_import_status_t import_status

462

= import_result->imports;

463

import_status != NULL;

464

import_status = import_status->next){

465

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

466

import_status->fpr);

467

if(import_status->result != GPG_ERR_NO_ERROR){

468

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

469

gpgme_strsource(import_status->result),

470

gpgme_strerror(import_status->result));

471

}

472

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

473

fprintf_plus(stderr,

474

import_status->status & GPGME_IMPORT_NEW

475

? "The key was new.\n"

476

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

477

fprintf_plus(stderr,

478

import_status->status & GPGME_IMPORT_UID

479

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

480

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

481

fprintf_plus(stderr,

482

import_status->status & GPGME_IMPORT_SIG

483

? "The key contained new signatures.\n"

484

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

485

fprintf_plus(stderr,

486

import_status->status & GPGME_IMPORT_SUBKEY

487

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

488

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

489

fprintf_plus(stderr,

490

import_status->status & GPGME_IMPORT_SECRET

491

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

492

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

493

}

494

return false;

495

}

496

}

497

276

498

ret = close(fd);

277

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

499

278

if(ret == -1){

500

279

perror_plus("close");

501

280

}

538

317

}

539

318

540

319

/* Create new GPGME "context" */

541

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

320

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

542

321

if(rc != GPG_ERR_NO_ERROR){

543

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

544

gpgme_strsource(rc), gpgme_strerror(rc));

322

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

323

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

324

gpgme_strerror(rc));

545

325

return false;

546

326

}

547

327

556

336

* Decrypt OpenPGP data.

557

337

* Returns -1 on error

558

338

*/

559

__attribute__((nonnull, warn_unused_result))

560

339

static ssize_t pgp_packet_decrypt(const char *cryptotext,

561

340

size_t crypto_size,

562

char **plaintext,

563

mandos_context *mc){

341

char **plaintext){

564

342

gpgme_data_t dh_crypto, dh_plain;

565

343

gpgme_error_t rc;

566

344

ssize_t ret;

583

361

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

584

362

rc = gpgme_data_new(&dh_plain);

585

363

if(rc != GPG_ERR_NO_ERROR){

586

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

364

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

365

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

587

366

gpgme_strsource(rc), gpgme_strerror(rc));

588

367

gpgme_data_release(dh_crypto);

589

368

return -1;

591

370

592

371

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

593

372

data buffer */

594

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

373

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

595

374

if(rc != GPG_ERR_NO_ERROR){

596

375

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

597

376

gpgme_strsource(rc), gpgme_strerror(rc));

598

377

plaintext_length = -1;

599

378

if(debug){

600

379

gpgme_decrypt_result_t result;

601

result = gpgme_op_decrypt_result(mc->ctx);

380

result = gpgme_op_decrypt_result(mc.ctx);

602

381

if(result == NULL){

603

382

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

604

383

} else {

605

if(result->unsupported_algorithm != NULL) {

606

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

607

result->unsupported_algorithm);

608

}

609

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

610

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

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);

611

388

if(result->file_name != NULL){

612

389

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

613

390

}

614

615

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

616

r = r->next){

391

gpgme_recipient_t recipient;

392

recipient = result->recipients;

393

while(recipient != NULL){

617

394

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

618

gpgme_pubkey_algo_name(r->pubkey_algo));

619

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

395

gpgme_pubkey_algo_name

396

(recipient->pubkey_algo));

397

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

620

398

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

621

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

399

recipient->status == GPG_ERR_NO_SECKEY

400

? "No" : "Yes");

401

recipient = recipient->next;

622

402

}

623

403

}

624

404

}

680

460

return plaintext_length;

681

461

}

682

462

683

__attribute__((warn_unused_result, const))

684

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

685

if(str == NULL)

686

return "(unknown)";

687

return str;

688

}

689

690

__attribute__((warn_unused_result))

691

static const char *safer_gnutls_strerror(int value){

692

const char *ret = gnutls_strerror(value);

693

return safe_string(ret);

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;

694

469

}

695

470

696

471

/* GnuTLS log function callback */

697

__attribute__((nonnull))

698

472

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

699

473

const char* string){

700

474

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

701

475

}

702

476

703

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

704

477

static int init_gnutls_global(const char *pubkeyfilename,

705

const char *seckeyfilename,

706

const char *dhparamsfilename,

707

mandos_context *mc){

478

const char *seckeyfilename){

708

479

int ret;

709

480

710

481

if(debug){

711

482

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

712

483

}

713

484

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

714

492

if(debug){

715

493

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

716

494

* - GnuTLS manual

720

498

}

721

499

722

500

/* OpenPGP credentials */

723

ret = gnutls_certificate_allocate_credentials(&mc->cred);

501

ret = gnutls_certificate_allocate_credentials(&mc.cred);

724

502

if(ret != GNUTLS_E_SUCCESS){

725

503

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

726

504

safer_gnutls_strerror(ret));

505

gnutls_global_deinit();

727

506

return -1;

728

507

}

729

508

730

509

if(debug){

731

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

732

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

510

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

511

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

733

512

pubkeyfilename,

734

513

seckeyfilename);

735

514

}

736

515

737

#if GNUTLS_VERSION_NUMBER >= 0x030606

738

ret = gnutls_certificate_set_rawpk_key_file

739

(mc->cred, pubkeyfilename, seckeyfilename,

740

GNUTLS_X509_FMT_PEM, /* format */

741

NULL, /* pass */

742

/* key_usage */

743

GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,

744

NULL, /* names */

745

0, /* names_length */

746

/* privkey_flags */

747

GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,

748

0); /* pkcs11_flags */

749

#elif GNUTLS_VERSION_NUMBER < 0x030600

750

516

ret = gnutls_certificate_set_openpgp_key_file

751

(mc->cred, pubkeyfilename, seckeyfilename,

517

(mc.cred, pubkeyfilename, seckeyfilename,

752

518

GNUTLS_OPENPGP_FMT_BASE64);

753

#else

754

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

755

#endif

756

519

if(ret != GNUTLS_E_SUCCESS){

757

520

fprintf_plus(stderr,

758

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

521

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

759

522

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

760

523

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

761

524

safer_gnutls_strerror(ret));

763

526

}

764

527

765

528

/* GnuTLS server initialization */

766

ret = gnutls_dh_params_init(&mc->dh_params);

529

ret = gnutls_dh_params_init(&mc.dh_params);

767

530

if(ret != GNUTLS_E_SUCCESS){

768

531

fprintf_plus(stderr, "Error in GnuTLS DH parameter"

769

532

" initialization: %s\n",

770

533

safer_gnutls_strerror(ret));

771

534

goto globalfail;

772

535

}

773

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

774

if(dhparamsfilename != NULL){

775

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

776

do {

777

int dhpfile = open(dhparamsfilename, O_RDONLY);

778

if(dhpfile == -1){

779

perror_plus("open");

780

dhparamsfilename = NULL;

781

break;

782

}

783

size_t params_capacity = 0;

784

while(true){

785

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

786

(size_t)params.size,

787

(size_t)params_capacity);

788

if(params_capacity == 0){

789

perror_plus("incbuffer");

790

free(params.data);

791

params.data = NULL;

792

dhparamsfilename = NULL;

793

break;

794

}

795

ssize_t bytes_read = read(dhpfile,

796

params.data + params.size,

797

BUFFER_SIZE);

798

/* EOF */

799

if(bytes_read == 0){

800

break;

801

}

802

/* check bytes_read for failure */

803

if(bytes_read < 0){

804

perror_plus("read");

805

free(params.data);

806

params.data = NULL;

807

dhparamsfilename = NULL;

808

break;

809

}

810

params.size += (unsigned int)bytes_read;

811

}

812

ret = close(dhpfile);

813

if(ret == -1){

814

perror_plus("close");

815

}

816

if(params.data == NULL){

817

dhparamsfilename = NULL;

818

}

819

if(dhparamsfilename == NULL){

820

break;

821

}

822

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

823

GNUTLS_X509_FMT_PEM);

824

if(ret != GNUTLS_E_SUCCESS){

825

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

826

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

827

safer_gnutls_strerror(ret));

828

dhparamsfilename = NULL;

829

}

830

free(params.data);

831

} while(false);

832

}

833

if(dhparamsfilename == NULL){

834

if(mc->dh_bits == 0){

835

#if GNUTLS_VERSION_NUMBER < 0x030600

836

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

837

/* Try to read the private key file */

838

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

839

do {

840

int secfile = open(seckeyfilename, O_RDONLY);

841

if(secfile == -1){

842

perror_plus("open");

843

break;

844

}

845

size_t buffer_capacity = 0;

846

while(true){

847

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

848

(size_t)buffer.size,

849

(size_t)buffer_capacity);

850

if(buffer_capacity == 0){

851

perror_plus("incbuffer");

852

free(buffer.data);

853

buffer.data = NULL;

854

break;

855

}

856

ssize_t bytes_read = read(secfile,

857

buffer.data + buffer.size,

858

BUFFER_SIZE);

859

/* EOF */

860

if(bytes_read == 0){

861

break;

862

}

863

/* check bytes_read for failure */

864

if(bytes_read < 0){

865

perror_plus("read");

866

free(buffer.data);

867

buffer.data = NULL;

868

break;

869

}

870

buffer.size += (unsigned int)bytes_read;

871

}

872

close(secfile);

873

} while(false);

874

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

875

gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;

876

if(buffer.data != NULL){

877

{

878

gnutls_openpgp_privkey_t privkey = NULL;

879

ret = gnutls_openpgp_privkey_init(&privkey);

880

if(ret != GNUTLS_E_SUCCESS){

881

fprintf_plus(stderr, "Error initializing OpenPGP key"

882

" structure: %s",

883

safer_gnutls_strerror(ret));

884

free(buffer.data);

885

buffer.data = NULL;

886

} else {

887

ret = gnutls_openpgp_privkey_import

888

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

889

if(ret != GNUTLS_E_SUCCESS){

890

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

891

safer_gnutls_strerror(ret));

892

privkey = NULL;

893

}

894

free(buffer.data);

895

buffer.data = NULL;

896

if(privkey != NULL){

897

/* Use private key to suggest an appropriate

898

sec_param */

899

sec_param = gnutls_openpgp_privkey_sec_param(privkey);

900

gnutls_openpgp_privkey_deinit(privkey);

901

if(debug){

902

fprintf_plus(stderr, "This OpenPGP key implies using"

903

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

904

safe_string(gnutls_sec_param_get_name

905

(sec_param)));

906

}

907

}

908

}

909

}

910

if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){

911

/* Err on the side of caution */

912

sec_param = GNUTLS_SEC_PARAM_ULTRA;

913

if(debug){

914

fprintf_plus(stderr, "Falling back to security parameter"

915

" \"%s\"\n",

916

safe_string(gnutls_sec_param_get_name

917

(sec_param)));

918

}

919

}

920

}

921

unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);

922

if(uret != 0){

923

mc->dh_bits = uret;

924

if(debug){

925

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

926

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

927

safe_string(gnutls_sec_param_get_name

928

(sec_param)),

929

mc->dh_bits);

930

}

931

} else {

932

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

933

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

934

safe_string(gnutls_sec_param_get_name

935

(sec_param)),

936

safer_gnutls_strerror(ret));

937

goto globalfail;

938

}

939

#endif

940

} else { /* dh_bits != 0 */

941

if(debug){

942

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

943

mc->dh_bits);

944

}

945

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

946

if(ret != GNUTLS_E_SUCCESS){

947

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

948

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

949

safer_gnutls_strerror(ret));

950

goto globalfail;

951

}

952

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

953

}

954

}

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);

955

544

956

545

return 0;

957

546

958

547

globalfail:

959

548

960

gnutls_certificate_free_credentials(mc->cred);

961

gnutls_dh_params_deinit(mc->dh_params);

549

gnutls_certificate_free_credentials(mc.cred);

550

gnutls_global_deinit();

551

gnutls_dh_params_deinit(mc.dh_params);

962

552

return -1;

963

553

}

964

554

965

__attribute__((nonnull, warn_unused_result))

966

static int init_gnutls_session(gnutls_session_t *session,

967

mandos_context *mc){

555

static int init_gnutls_session(gnutls_session_t *session){

968

556

int ret;

969

557

/* GnuTLS session creation */

970

558

do {

971

ret = gnutls_init(session, (GNUTLS_SERVER

972

#if GNUTLS_VERSION_NUMBER >= 0x030506

973

| GNUTLS_NO_TICKETS

974

#endif

975

#if GNUTLS_VERSION_NUMBER >= 0x030606

976

| GNUTLS_ENABLE_RAWPK

977

#endif

978

));

559

ret = gnutls_init(session, GNUTLS_SERVER);

979

560

if(quit_now){

980

561

return -1;

981

562

}

989

570

{

990

571

const char *err;

991

572

do {

992

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

573

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

993

574

if(quit_now){

994

575

gnutls_deinit(*session);

995

576

return -1;

1006

587

1007

588

do {

1008

589

ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,

1009

mc->cred);

590

mc.cred);

1010

591

if(quit_now){

1011

592

gnutls_deinit(*session);

1012

593

return -1;

1022

603

/* ignore client certificate if any. */

1023

604

gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);

1024

605

606

gnutls_dh_set_prime_bits(*session, mc.dh_bits);

607

1025

608

return 0;

1026

609

}

1027

610

1029

612

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

1030

613

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

1031

614

1032

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

1033

__attribute__((nonnull, warn_unused_result))

1034

static bool add_delete_local_route(const bool add,

1035

const char *address,

1036

AvahiIfIndex if_index){

1037

int ret;

1038

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

1039

char add_arg[] = "add";

1040

char delete_arg[] = "delete";

1041

char debug_flag[] = "--debug";

1042

char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");

1043

if(pluginhelperdir == NULL){

1044

if(debug){

1045

fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"

1046

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

1047

}

1048

return false;

1049

}

1050

1051

char interface[IF_NAMESIZE];

1052

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

1053

perror_plus("if_indextoname");

1054

return false;

1055

}

1056

1057

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

1058

if(devnull == -1){

1059

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

1060

return false;

1061

}

1062

pid_t pid = fork();

1063

if(pid == 0){

1064

/* Child */

1065

/* Raise privileges */

1066

errno = raise_privileges_permanently();

1067

if(errno != 0){

1068

perror_plus("Failed to raise privileges");

1069

/* _exit(EX_NOPERM); */

1070

} else {

1071

/* Set group */

1072

errno = 0;

1073

ret = setgid(0);

1074

if(ret == -1){

1075

perror_plus("setgid");

1076

close(devnull);

1077

_exit(EX_NOPERM);

1078

}

1079

/* Reset supplementary groups */

1080

errno = 0;

1081

ret = setgroups(0, NULL);

1082

if(ret == -1){

1083

perror_plus("setgroups");

1084

close(devnull);

1085

_exit(EX_NOPERM);

1086

}

1087

}

1088

ret = dup2(devnull, STDIN_FILENO);

1089

if(ret == -1){

1090

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

1091

close(devnull);

1092

_exit(EX_OSERR);

1093

}

1094

ret = close(devnull);

1095

if(ret == -1){

1096

perror_plus("close");

1097

}

1098

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

1099

if(ret == -1){

1100

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

1101

_exit(EX_OSERR);

1102

}

1103

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

1104

O_RDONLY

1105

| O_DIRECTORY

1106

| O_PATH

1107

| O_CLOEXEC));

1108

if(helperdir_fd == -1){

1109

perror_plus("open");

1110

_exit(EX_UNAVAILABLE);

1111

}

1112

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

1113

helper, O_RDONLY));

1114

if(helper_fd == -1){

1115

perror_plus("openat");

1116

close(helperdir_fd);

1117

_exit(EX_UNAVAILABLE);

1118

}

1119

close(helperdir_fd);

1120

#ifdef __GNUC__

1121

#pragma GCC diagnostic push

1122

#pragma GCC diagnostic ignored "-Wcast-qual"

1123

#endif

1124

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

1125

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

1126

interface, debug ? debug_flag : NULL, NULL },

1127

environ) == -1){

1128

#ifdef __GNUC__

1129

#pragma GCC diagnostic pop

1130

#endif

1131

perror_plus("fexecve");

1132

_exit(EXIT_FAILURE);

1133

}

1134

}

1135

if(pid == -1){

1136

perror_plus("fork");

1137

close(devnull);

1138

return false;

1139

}

1140

ret = close(devnull);

1141

if(ret == -1){

1142

perror_plus("close");

1143

}

1144

int status;

1145

pid_t pret = -1;

1146

errno = 0;

1147

do {

1148

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

1149

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

1150

int errno_raising = 0;

1151

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

1152

errno_raising = errno;

1153

perror_plus("Failed to raise privileges in order to"

1154

" kill helper program");

1155

}

1156

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

1157

perror_plus("kill");

1158

}

1159

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

1160

perror_plus("Failed to lower privileges after killing"

1161

" helper program");

1162

}

1163

return false;

1164

}

1165

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

1166

if(pret == -1){

1167

perror_plus("waitpid");

1168

return false;

1169

}

1170

if(WIFEXITED(status)){

1171

if(WEXITSTATUS(status) != 0){

1172

fprintf_plus(stderr, "Error: iprouteadddel exited"

1173

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

1174

return false;

1175

}

1176

return true;

1177

}

1178

if(WIFSIGNALED(status)){

1179

fprintf_plus(stderr, "Error: iprouteadddel died by"

1180

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

1181

return false;

1182

}

1183

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

1184

return false;

1185

}

1186

1187

__attribute__((nonnull, warn_unused_result))

1188

static bool add_local_route(const char *address,

1189

AvahiIfIndex if_index){

1190

if(debug){

1191

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

1192

}

1193

return add_delete_local_route(true, address, if_index);

1194

}

1195

1196

__attribute__((nonnull, warn_unused_result))

1197

static bool delete_local_route(const char *address,

1198

AvahiIfIndex if_index){

1199

if(debug){

1200

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

1201

}

1202

return add_delete_local_route(false, address, if_index);

1203

}

1204

1205

615

/* Called when a Mandos server is found */

1206

__attribute__((nonnull, warn_unused_result))

1207

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

616

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

1208

617

AvahiIfIndex if_index,

1209

int af, mandos_context *mc){

618

int af){

1210

619

int ret, tcp_sd = -1;

1211

620

ssize_t sret;

1212

struct sockaddr_storage to;

621

union {

622

struct sockaddr_in in;

623

struct sockaddr_in6 in6;

624

} to;

1213

625

char *buffer = NULL;

1214

626

char *decrypted_buffer = NULL;

1215

627

size_t buffer_length = 0;

1218

630

int retval = -1;

1219

631

gnutls_session_t session;

1220

632

int pf; /* Protocol family */

1221

bool route_added = false;

1222

633

1223

634

errno = 0;

1224

635

1240

651

return -1;

1241

652

}

1242

653

1243

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

1244

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

1245

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

1246

bool match = false;

1247

{

1248

char *interface = NULL;

1249

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

1250

mc->interfaces_size,

1251

interface))){

1252

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

1253

match = true;

1254

break;

1255

}

1256

}

1257

}

1258

if(not match){

1259

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

1260

connect to the server */

1261

if(debug){

1262

char interface[IF_NAMESIZE];

1263

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

1264

perror_plus("if_indextoname");

1265

} else {

1266

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

1267

" \"%s\"\n",

1268

if_indextoname((unsigned int)if_index,

1269

interface));

1270

}

1271

}

1272

return -1;

1273

}

1274

}

1275

1276

ret = init_gnutls_session(&session, mc);

654

ret = init_gnutls_session(&session);

1277

655

if(ret != 0){

1278

656

return -1;

1279

657

}

1280

658

1281

659

if(debug){

1282

660

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

1283

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

661

PRIu16 "\n", ip, port);

1284

662

}

1285

663

1286

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

664

tcp_sd = socket(pf, SOCK_STREAM, 0);

1287

665

if(tcp_sd < 0){

1288

666

int e = errno;

1289

667

perror_plus("socket");

1296

674

goto mandos_end;

1297

675

}

1298

676

677

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

1299

678

if(af == AF_INET6){

1300

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

1301

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

1302

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

679

to.in6.sin6_family = (sa_family_t)af;

680

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

1303

681

} else { /* IPv4 */

1304

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

1305

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

1306

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

682

to.in.sin_family = (sa_family_t)af;

683

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

1307

684

}

1308

685

if(ret < 0 ){

1309

686

int e = errno;

1318

695

goto mandos_end;

1319

696

}

1320

697

if(af == AF_INET6){

1321

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

1322

if(IN6_IS_ADDR_LINKLOCAL

1323

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

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*/

1324

705

if(if_index == AVAHI_IF_UNSPEC){

1325

706

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

1326

707

" incomplete without a network interface\n");

1328

709

goto mandos_end;

1329

710

}

1330

711

/* Set the network interface number as scope */

1331

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

712

to.in6.sin6_scope_id = (uint32_t)if_index;

1332

713

}

1333

714

} else {

1334

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

715

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

716

-Wconversion and

717

-Wunreachable-code */

1335

718

}

1336

719

1337

720

if(quit_now){

1345

728

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

1346

729

perror_plus("if_indextoname");

1347

730

} else {

1348

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

1349

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

731

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

732

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

1350

733

}

1351

734

} else {

1352

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

1353

ip, (uintmax_t)port);

735

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

736

ip, port);

1354

737

}

1355

738

char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?

1356

739

INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";

1357

if(af == AF_INET6){

1358

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

1359

sizeof(struct sockaddr_in6),

1360

addrstr, sizeof(addrstr), NULL, 0,

1361

NI_NUMERICHOST);

1362

} else {

1363

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

1364

sizeof(struct sockaddr_in),

1365

addrstr, sizeof(addrstr), NULL, 0,

1366

NI_NUMERICHOST);

1367

}

1368

if(ret == EAI_SYSTEM){

1369

perror_plus("getnameinfo");

1370

} else if(ret != 0) {

1371

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

1372

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

1373

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

1374

}

1375

}

1376

1377

if(quit_now){

1378

errno = EINTR;

1379

goto mandos_end;

1380

}

1381

1382

while(true){

1383

if(af == AF_INET6){

1384

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

1385

sizeof(struct sockaddr_in6));

1386

} else {

1387

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

1388

sizeof(struct sockaddr_in));

1389

}

1390

if(ret < 0){

1391

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

1392

and if_index != AVAHI_IF_UNSPEC

1393

and connect_to == NULL

1394

and not route_added and

1395

((af == AF_INET6 and not

1396

IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)

1397

&to)->sin6_addr)))

1398

or (af == AF_INET and

1399

/* Not a a IPv4LL address */

1400

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

1401

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

1402

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

1403

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

1404

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

1405

connect to a Mandos server announced by Avahi on a server

1406

host with a global address. Work around this by retrying

1407

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

1408

1409

Avahi bug reference:

1410

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

1411

https://bugs.debian.org/587961

1412

*/

1413

if(debug){

1414

fprintf_plus(stderr, "Mandos server unreachable, trying"

1415

" direct route\n");

1416

}

1417

int e = errno;

1418

route_added = add_local_route(ip, if_index);

1419

if(route_added){

1420

continue;

1421

}

1422

errno = e;

1423

}

1424

if(errno != ECONNREFUSED or debug){

1425

int e = errno;

1426

perror_plus("connect");

1427

errno = e;

1428

}

1429

goto mandos_end;

1430

}

1431

1432

if(quit_now){

1433

errno = EINTR;

1434

goto mandos_end;

1435

}

1436

break;

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;

1437

779

}

1438

780

1439

781

const char *out = mandos_protocol_version;

1475

817

goto mandos_end;

1476

818

}

1477

819

1478

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

1479

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

1480

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

1481

gnutls_transport_set_ptr(session,

1482

(gnutls_transport_ptr_t)(intptr_t)tcp_sd);

820

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

821

gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);

1483

822

1484

823

if(quit_now){

1485

824

errno = EINTR;

1590

929

if(buffer_length > 0){

1591

930

ssize_t decrypted_buffer_size;

1592

931

decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,

1593

&decrypted_buffer, mc);

932

&decrypted_buffer);

1594

933

if(decrypted_buffer_size >= 0){

1595

934

1596

clearerr(stdout);

1597

935

written = 0;

1598

936

while(written < (size_t) decrypted_buffer_size){

1599

937

if(quit_now){

1615

953

}

1616

954

written += (size_t)ret;

1617

955

}

1618

ret = fflush(stdout);

1619

if(ret != 0){

1620

int e = errno;

1621

if(debug){

1622

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

1623

strerror(errno));

1624

}

1625

errno = e;

1626

goto mandos_end;

1627

}

1628

956

retval = 0;

1629

957

}

1630

958

}

1633

961

1634

962

mandos_end:

1635

963

{

1636

if(route_added){

1637

if(not delete_local_route(ip, if_index)){

1638

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

1639

" interface %d", ip, if_index);

1640

}

1641

}

1642

964

int e = errno;

1643

965

free(decrypted_buffer);

1644

966

free(buffer);

1645

967

if(tcp_sd >= 0){

1646

ret = close(tcp_sd);

968

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

1647

969

}

1648

970

if(ret == -1){

1649

971

if(e == 0){

1674

996

AVAHI_GCC_UNUSED AvahiStringList *txt,

1675

997

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1676

998

flags,

1677

void *mc){

1678

if(r == NULL){

1679

return;

1680

}

999

AVAHI_GCC_UNUSED void* userdata){

1000

assert(r);

1681

1001

1682

1002

/* Called whenever a service has been resolved successfully or

1683

1003

timed out */

1684

1004

1685

1005

if(quit_now){

1686

avahi_s_service_resolver_free(r);

1687

1006

return;

1688

1007

}

1689

1008

1693

1012

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

1694

1013

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

1695

1014

domain,

1696

avahi_strerror(avahi_server_errno

1697

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

1015

avahi_strerror(avahi_server_errno(mc.server)));

1698

1016

break;

1699

1017

1700

1018

case AVAHI_RESOLVER_FOUND:

1706

1024

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

1707

1025

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

1708

1026

}

1709

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

1710

interface,

1711

avahi_proto_to_af(proto),

1712

mc);

1027

int ret = start_mandos_communication(ip, port, interface,

1028

avahi_proto_to_af(proto));

1713

1029

if(ret == 0){

1714

avahi_simple_poll_quit(simple_poll);

1030

avahi_simple_poll_quit(mc.simple_poll);

1715

1031

} else {

1716

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

1717

avahi_proto_to_af(proto),

1718

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

1719

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

1720

" list\n", name);

1721

}

1032

ret = add_server(ip, port, interface,

1033

avahi_proto_to_af(proto));

1722

1034

}

1723

1035

}

1724

1036

}

1734

1046

const char *domain,

1735

1047

AVAHI_GCC_UNUSED AvahiLookupResultFlags

1736

1048

flags,

1737

void *mc){

1738

if(b == NULL){

1739

return;

1740

}

1049

AVAHI_GCC_UNUSED void* userdata){

1050

assert(b);

1741

1051

1742

1052

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

1743

1053

is removed from the LAN */

1751

1061

case AVAHI_BROWSER_FAILURE:

1752

1062

1753

1063

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

1754

avahi_strerror(avahi_server_errno

1755

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

1756

avahi_simple_poll_quit(simple_poll);

1064

avahi_strerror(avahi_server_errno(mc.server)));

1065

avahi_simple_poll_quit(mc.simple_poll);

1757

1066

return;

1758

1067

1759

1068

case AVAHI_BROWSER_NEW:

1762

1071

the callback function is called the Avahi server will free the

1763

1072

resolver for us. */

1764

1073

1765

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

1766

interface, protocol, name, type,

1767

domain, protocol, 0,

1768

resolve_callback, mc) == NULL)

1074

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

1075

name, type, domain, protocol, 0,

1076

resolve_callback, NULL) == NULL)

1769

1077

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

1770

1078

" %s\n", name,

1771

avahi_strerror(avahi_server_errno

1772

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

1079

avahi_strerror(avahi_server_errno(mc.server)));

1773

1080

break;

1774

1081

1775

1082

case AVAHI_BROWSER_REMOVE:

1794

1101

signal_received = sig;

1795

1102

int old_errno = errno;

1796

1103

/* set main loop to exit */

1797

if(simple_poll != NULL){

1798

avahi_simple_poll_quit(simple_poll);

1104

if(mc.simple_poll != NULL){

1105

avahi_simple_poll_quit(mc.simple_poll);

1799

1106

}

1800

1107

errno = old_errno;

1801

1108

}

1802

1109

1803

__attribute__((nonnull, warn_unused_result))

1804

1110

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

1805

1111

int ret;

1806

int old_errno;

1807

1112

1808

1113

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

1809

1114

if(s < 0){

1810

old_errno = errno;

1811

1115

perror_plus("socket");

1812

errno = old_errno;

1813

1116

return false;

1814

1117

}

1815

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

1816

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

1118

strcpy(ifr->ifr_name, ifname);

1817

1119

ret = ioctl(s, SIOCGIFFLAGS, ifr);

1818

1120

if(ret == -1){

1819

1121

if(debug){

1820

old_errno = errno;

1821

1122

perror_plus("ioctl SIOCGIFFLAGS");

1822

errno = old_errno;

1823

}

1824

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

1825

old_errno = errno;

1826

perror_plus("close");

1827

errno = old_errno;

1828

1123

}

1829

1124

return false;

1830

1125

}

1831

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

1832

old_errno = errno;

1833

perror_plus("close");

1834

errno = old_errno;

1835

}

1836

1126

return true;

1837

1127

}

1838

1128

1839

__attribute__((nonnull, warn_unused_result))

1840

1129

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

1841

1130

1842

1131

/* Reject the loopback device */

1884

1173

* corresponds to an acceptable network device.

1885

1174

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

1886

1175

*/

1887

__attribute__((nonnull, warn_unused_result))

1888

1176

int good_interface(const struct dirent *if_entry){

1889

1177

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

1890

1178

return 0;

1906

1194

}

1907

1195

1908

1196

/*

1909

* This function determines if a network interface is up.

1910

*/

1911

__attribute__((nonnull, warn_unused_result))

1912

bool interface_is_up(const char *interface){

1913

struct ifreq ifr;

1914

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

1915

if(debug){

1916

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

1917

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

1918

}

1919

return false;

1920

}

1921

1922

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

1923

}

1924

1925

/*

1926

* This function determines if a network interface is running

1927

*/

1928

__attribute__((nonnull, warn_unused_result))

1929

bool interface_is_running(const char *interface){

1930

struct ifreq ifr;

1931

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

1932

if(debug){

1933

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

1934

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

1935

}

1936

return false;

1937

}

1938

1939

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

1940

}

1941

1942

__attribute__((nonnull, pure, warn_unused_result))

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

1943

1239

int notdotentries(const struct dirent *direntry){

1944

1240

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

1945

1241

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

1952

1248

}

1953

1249

1954

1250

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

1955

__attribute__((nonnull, warn_unused_result))

1956

1251

int runnable_hook(const struct dirent *direntry){

1957

1252

int ret;

1958

1253

size_t sret;

1966

1261

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

1967

1262

"abcdefghijklmnopqrstuvwxyz"

1968

1263

"0123456789"

1969

"_.-");

1264

"_-");

1970

1265

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

1971

1266

/* Contains non-allowed characters */

1972

1267

if(debug){

1976

1271

return 0;

1977

1272

}

1978

1273

1979

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

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

1282

if(ret == -1){

1981

1283

if(debug){

1982

1284

perror_plus("Could not stat hook");

2006

1308

return 1;

2007

1309

}

2008

1310

2009

__attribute__((nonnull, warn_unused_result))

2010

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,

2011

mandos_context *mc){

1311

int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){

2012

1312

int ret;

2013

1313

struct timespec now;

2014

1314

struct timespec waited_time;

2015

1315

intmax_t block_time;

2016

1316

2017

1317

while(true){

2018

if(mc->current_server == NULL){

2019

if(debug){

1318

if(mc.current_server == NULL){

1319

if (debug){

2020

1320

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

2021

1321

" No timeout!\n");

2022

1322

}

2023

1323

ret = avahi_simple_poll_iterate(s, -1);

2024

1324

} else {

2025

if(debug){

1325

if (debug){

2026

1326

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

2027

1327

" it, or wait\n");

2028

1328

}

2035

1335

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

2036

1336

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

2037

1337

waited_time.tv_sec = (now.tv_sec

2038

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

1338

- mc.current_server->last_seen.tv_sec);

2039

1339

waited_time.tv_nsec = (now.tv_nsec

2040

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

1340

- mc.current_server->last_seen.tv_nsec);

2041

1341

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

2042

1342

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

2043

1343

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

2045

1345

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

2046

1346

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

2047

1347

2048

if(debug){

1348

if (debug){

2049

1349

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

2050

1350

block_time);

2051

1351

}

2052

1352

2053

1353

if(block_time <= 0){

2054

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

2055

mc->current_server->port,

2056

mc->current_server->if_index,

2057

mc->current_server->af, mc);

1354

ret = start_mandos_communication(mc.current_server->ip,

1355

mc.current_server->port,

1356

mc.current_server->if_index,

1357

mc.current_server->af);

2058

1358

if(ret == 0){

2059

avahi_simple_poll_quit(s);

1359

avahi_simple_poll_quit(mc.simple_poll);

2060

1360

return 0;

2061

1361

}

2062

1362

ret = clock_gettime(CLOCK_MONOTONIC,

2063

&mc->current_server->last_seen);

1363

&mc.current_server->last_seen);

2064

1364

if(ret == -1){

2065

1365

perror_plus("clock_gettime");

2066

1366

return -1;

2067

1367

}

2068

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

1368

mc.current_server = mc.current_server->next;

2069

1369

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

2070

1370

servers, but don't block */

2071

1371

}

2073

1373

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

2074

1374

}

2075

1375

if(ret != 0){

2076

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

1376

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

2077

1377

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

2078

1378

}

2079

1379

}

2080

1380

}

2081

1381

}

2082

1382

2083

__attribute__((nonnull))

2084

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

1383

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

2085

1384

const float delay){

2086

struct dirent **direntries = NULL;

2087

if(hookdir_fd == -1){

2088

hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH

2089

| O_CLOEXEC);

2090

if(hookdir_fd == -1){

2091

if(errno == ENOENT){

2092

if(debug){

2093

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

2094

" found\n", hookdir);

2095

}

2096

} else {

2097

perror_plus("open");

2098

}

2099

return;

2100

}

2101

}

2102

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

2103

if(devnull == -1){

2104

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

2105

return;

2106

}

2107

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

2108

runnable_hook, alphasort);

1385

struct dirent **direntries;

1386

struct dirent *direntry;

1387

int ret;

1388

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

1389

alphasort);

2109

1390

if(numhooks == -1){

2110

1391

perror_plus("scandir");

2111

close(devnull);

2112

return;

2113

}

2114

struct dirent *direntry;

2115

int ret;

2116

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

2117

direntry = direntries[i];

2118

if(debug){

2119

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

2120

direntry->d_name);

2121

}

2122

pid_t hook_pid = fork();

2123

if(hook_pid == 0){

2124

/* Child */

2125

/* Raise privileges */

2126

errno = raise_privileges_permanently();

2127

if(errno != 0){

2128

perror_plus("Failed to raise privileges");

2129

_exit(EX_NOPERM);

2130

}

2131

/* Set group */

2132

errno = 0;

2133

ret = setgid(0);

2134

if(ret == -1){

2135

perror_plus("setgid");

2136

_exit(EX_NOPERM);

2137

}

2138

/* Reset supplementary groups */

2139

errno = 0;

2140

ret = setgroups(0, NULL);

2141

if(ret == -1){

2142

perror_plus("setgroups");

2143

_exit(EX_NOPERM);

2144

}

2145

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

2146

if(ret == -1){

2147

perror_plus("setenv");

2148

_exit(EX_OSERR);

2149

}

2150

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

2151

if(ret == -1){

2152

perror_plus("setenv");

2153

_exit(EX_OSERR);

2154

}

2155

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

2156

if(ret == -1){

2157

perror_plus("setenv");

2158

_exit(EX_OSERR);

2159

}

2160

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

2161

if(ret == -1){

2162

perror_plus("setenv");

2163

_exit(EX_OSERR);

2164

}

2165

char *delaystring;

2166

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

2167

if(ret == -1){

1392

} else {

1393

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

1394

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

1395

direntry = direntries[i];

1396

char *fullname = NULL;

1397

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

1398

if(ret < 0){

2168

1399

perror_plus("asprintf");

2169

_exit(EX_OSERR);

2170

}

2171

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

2172

if(ret == -1){

1400

continue;

1401

}

1402

if(debug){

1403

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

1404

direntry->d_name);

1405

}

1406

pid_t hook_pid = fork();

1407

if(hook_pid == 0){

1408

/* Child */

1409

dup2(devnull, STDIN_FILENO);

1410

close(devnull);

1411

dup2(STDERR_FILENO, STDOUT_FILENO);

1412

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

1413

if(ret == -1){

1414

perror_plus("setenv");

1415

return false;

1416

}

1417

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

1418

if(ret == -1){

1419

perror_plus("setenv");

1420

return false;

1421

}

1422

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

1423

if(ret == -1){

1424

perror_plus("setenv");

1425

return false;

1426

}

1427

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

1428

if(ret == -1){

1429

perror_plus("setenv");

1430

return false;

1431

}

1432

char *delaystring;

1433

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

1434

if(ret == -1){

1435

perror_plus("asprintf");

1436

return false;

1437

}

1438

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

1439

if(ret == -1){

1440

free(delaystring);

1441

perror_plus("setenv");

1442

return false;

1443

}

2173

1444

free(delaystring);

2174

perror_plus("setenv");

2175

_exit(EX_OSERR);

2176

}

2177

free(delaystring);

2178

if(connect_to != NULL){

2179

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

2180

if(ret == -1){

2181

perror_plus("setenv");

2182

_exit(EX_OSERR);

2183

}

2184

}

2185

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

2186

direntry->d_name,

2187

O_RDONLY));

2188

if(hook_fd == -1){

2189

perror_plus("openat");

2190

_exit(EXIT_FAILURE);

2191

}

2192

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

2193

perror_plus("close");

2194

_exit(EXIT_FAILURE);

2195

}

2196

ret = dup2(devnull, STDIN_FILENO);

2197

if(ret == -1){

2198

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

2199

_exit(EX_OSERR);

2200

}

2201

ret = close(devnull);

2202

if(ret == -1){

2203

perror_plus("close");

2204

_exit(EX_OSERR);

2205

}

2206

ret = dup2(STDERR_FILENO, STDOUT_FILENO);

2207

if(ret == -1){

2208

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

2209

_exit(EX_OSERR);

2210

}

2211

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

2212

environ) == -1){

2213

perror_plus("fexecve");

2214

_exit(EXIT_FAILURE);

2215

}

2216

} else {

2217

if(hook_pid == -1){

2218

perror_plus("fork");

2219

free(direntry);

2220

continue;

2221

}

2222

int status;

2223

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

2224

perror_plus("waitpid");

2225

free(direntry);

2226

continue;

2227

}

2228

if(WIFEXITED(status)){

2229

if(WEXITSTATUS(status) != 0){

2230

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

2231

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

2232

WEXITSTATUS(status));

2233

free(direntry);

2234

continue;

2235

}

2236

} else if(WIFSIGNALED(status)){

2237

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

2238

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

2239

WTERMSIG(status));

2240

free(direntry);

2241

continue;

2242

} else {

2243

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

2244

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

2245

free(direntry);

2246

continue;

2247

}

2248

}

2249

if(debug){

2250

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

2251

direntry->d_name);

2252

}

2253

free(direntry);

2254

}

2255

free(direntries);

2256

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

2257

perror_plus("close");

2258

} else {

2259

hookdir_fd = -1;

2260

}

2261

close(devnull);

2262

}

2263

2264

__attribute__((nonnull, warn_unused_result))

2265

int bring_up_interface(const char *const interface,

2266

const float delay){

2267

int old_errno = errno;

2268

int ret;

2269

struct ifreq network;

2270

unsigned int if_index = if_nametoindex(interface);

2271

if(if_index == 0){

2272

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

2273

errno = old_errno;

2274

return ENXIO;

2275

}

2276

2277

if(quit_now){

2278

errno = old_errno;

2279

return EINTR;

2280

}

2281

2282

if(not interface_is_up(interface)){

2283

int ret_errno = 0;

2284

int ioctl_errno = 0;

2285

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

2286

ret_errno = errno;

2287

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

2288

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

2289

errno = old_errno;

2290

return ret_errno;

2291

}

2292

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

2293

2294

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

2295

if(sd == -1){

2296

ret_errno = errno;

2297

perror_plus("socket");

2298

errno = old_errno;

2299

return ret_errno;

2300

}

2301

2302

if(quit_now){

2303

ret = close(sd);

2304

if(ret == -1){

2305

perror_plus("close");

2306

}

2307

errno = old_errno;

2308

return EINTR;

2309

}

2310

2311

if(debug){

2312

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

2313

interface);

2314

}

2315

2316

/* Raise privileges */

2317

ret_errno = raise_privileges();

2318

if(ret_errno != 0){

2319

errno = ret_errno;

2320

perror_plus("Failed to raise privileges");

2321

}

2322

2323

#ifdef __linux__

2324

int ret_linux;

2325

bool restore_loglevel = false;

2326

if(ret_errno == 0){

2327

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

2328

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

2329

ret_linux = klogctl(8, NULL, 5);

2330

if(ret_linux == -1){

2331

perror_plus("klogctl");

2332

} else {

2333

restore_loglevel = true;

2334

}

2335

}

2336

#endif /* __linux__ */

2337

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

2338

ioctl_errno = errno;

2339

#ifdef __linux__

2340

if(restore_loglevel){

2341

ret_linux = klogctl(7, NULL, 0);

2342

if(ret_linux == -1){

2343

perror_plus("klogctl");

2344

}

2345

}

2346

#endif /* __linux__ */

2347

2348

/* If raise_privileges() succeeded above */

2349

if(ret_errno == 0){

2350

/* Lower privileges */

2351

ret_errno = lower_privileges();

2352

if(ret_errno != 0){

2353

errno = ret_errno;

2354

perror_plus("Failed to lower privileges");

2355

}

2356

}

2357

2358

/* Close the socket */

2359

ret = close(sd);

2360

if(ret == -1){

2361

perror_plus("close");

2362

}

2363

2364

if(ret_setflags == -1){

2365

errno = ioctl_errno;

2366

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

2367

errno = old_errno;

2368

return ioctl_errno;

2369

}

2370

} else if(debug){

2371

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

2372

interface);

2373

}

2374

2375

/* Sleep checking until interface is running.

2376

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

2377

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

2378

if(interface_is_running(interface)){

2379

break;

2380

}

2381

struct timespec sleeptime = { .tv_nsec = 250000000 };

2382

ret = nanosleep(&sleeptime, NULL);

2383

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

2384

perror_plus("nanosleep");

2385

}

2386

}

2387

2388

errno = old_errno;

2389

return 0;

2390

}

2391

2392

__attribute__((nonnull, warn_unused_result))

2393

int take_down_interface(const char *const interface){

2394

int old_errno = errno;

2395

struct ifreq network;

2396

unsigned int if_index = if_nametoindex(interface);

2397

if(if_index == 0){

2398

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

2399

errno = old_errno;

2400

return ENXIO;

2401

}

2402

if(interface_is_up(interface)){

2403

int ret_errno = 0;

2404

int ioctl_errno = 0;

2405

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

2406

ret_errno = errno;

2407

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

2408

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

2409

errno = old_errno;

2410

return ret_errno;

2411

}

2412

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

2413

2414

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

2415

if(sd == -1){

2416

ret_errno = errno;

2417

perror_plus("socket");

2418

errno = old_errno;

2419

return ret_errno;

2420

}

2421

2422

if(debug){

2423

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

2424

interface);

2425

}

2426

2427

/* Raise privileges */

2428

ret_errno = raise_privileges();

2429

if(ret_errno != 0){

2430

errno = ret_errno;

2431

perror_plus("Failed to raise privileges");

2432

}

2433

2434

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

2435

ioctl_errno = errno;

2436

2437

/* If raise_privileges() succeeded above */

2438

if(ret_errno == 0){

2439

/* Lower privileges */

2440

ret_errno = lower_privileges();

2441

if(ret_errno != 0){

2442

errno = ret_errno;

2443

perror_plus("Failed to lower privileges");

2444

}

2445

}

2446

2447

/* Close the socket */

2448

int ret = close(sd);

2449

if(ret == -1){

2450

perror_plus("close");

2451

}

2452

2453

if(ret_setflags == -1){

2454

errno = ioctl_errno;

2455

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2456

errno = old_errno;

2457

return ioctl_errno;

2458

}

2459

} else if(debug){

2460

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

2461

interface);

2462

}

2463

2464

errno = old_errno;

2465

return 0;

1445

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

1446

perror_plus("execl");

1447

} else {

1448

int status;

1449

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

1450

perror_plus("waitpid");

1451

free(fullname);

1452

continue;

1453

}

1454

if(WIFEXITED(status)){

1455

if(WEXITSTATUS(status) != 0){

1456

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

1457

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

1458

WEXITSTATUS(status));

1459

free(fullname);

1460

continue;

1461

}

1462

} else if(WIFSIGNALED(status)){

1463

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

1464

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

1465

WTERMSIG(status));

1466

free(fullname);

1467

continue;

1468

} else {

1469

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

1470

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

1471

free(fullname);

1472

continue;

1473

}

1474

}

1475

free(fullname);

1476

if(debug){

1477

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

1478

direntry->d_name);

1479

}

1480

}

1481

close(devnull);

1482

}

1483

return true;

2466

1484

}

2467

1485

2468

1486

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

2469

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

2470

#if GNUTLS_VERSION_NUMBER >= 0x030606

2471

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

2472

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

2473

":%PROFILE_ULTRA",

2474

#elif GNUTLS_VERSION_NUMBER < 0x030600

2475

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

2476

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

2477

#else

2478

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

2479

#endif

2480

.current_server = NULL, .interfaces = NULL,

2481

.interfaces_size = 0 };

2482

1487

AvahiSServiceBrowser *sb = NULL;

2483

error_t ret_errno;

1488

int error;

2484

1489

int ret;

2485

1490

intmax_t tmpmax;

2486

1491

char *tmp;

2487

1492

int exitcode = EXIT_SUCCESS;

2488

char *interfaces_to_take_down = NULL;

2489

size_t interfaces_to_take_down_size = 0;

2490

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

2491

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

2492

char *tempdir = NULL;

1493

const char *interface = "";

1494

struct ifreq network;

1495

int sd = -1;

1496

bool take_down_interface = false;

1497

uid_t uid;

1498

gid_t gid;

1499

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

1500

bool tempdir_created = false;

2493

1501

AvahiIfIndex if_index = AVAHI_IF_UNSPEC;

2494

1502

const char *seckey = PATHDIR "/" SECKEY;

2495

1503

const char *pubkey = PATHDIR "/" PUBKEY;

2496

#if GNUTLS_VERSION_NUMBER >= 0x030606

2497

const char *tls_privkey = PATHDIR "/" TLS_PRIVKEY;

2498

const char *tls_pubkey = PATHDIR "/" TLS_PUBKEY;

2499

#endif

2500

const char *dh_params_file = NULL;

2501

char *interfaces_hooks = NULL;

2502

1504

2503

1505

bool gnutls_initialized = false;

2504

1506

bool gpgme_initialized = false;

2550

1552

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

2551

1553

.arg = "FILE",

2552

1554

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

2553

.group = 1 },

2554

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

2555

.arg = "FILE",

2556

#if GNUTLS_VERSION_NUMBER >= 0x030606

2557

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

2558

#else

2559

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

2560

#endif

2561

.group = 1 },

2562

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

2563

.arg = "FILE",

2564

#if GNUTLS_VERSION_NUMBER >= 0x030606

2565

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

2566

#else

2567

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

2568

#endif

2569

.group = 1 },

1555

.group = 2 },

2570

1556

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

2571

1557

.arg = "BITS",

2572

1558

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

2573

1559

" Diffie-Hellman key exchange",

2574

1560

.group = 2 },

2575

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

2576

.arg = "FILE",

2577

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

2578

" for the Diffie-Hellman key exchange",

2579

.group = 2 },

2580

1561

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

2581

1562

.arg = "STRING",

2582

1563

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

2587

1568

.group = 2 },

2588

1569

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

2589

1570

.arg = "SECONDS",

2590

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

1571

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

2591

1572

.group = 2 },

2592

1573

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

2593

1574

.arg = "DIR",

2616

1597

connect_to = arg;

2617

1598

break;

2618

1599

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

2619

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

2620

arg, (int)',');

2621

if(ret_errno != 0){

2622

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

2623

}

1600

interface = arg;

2624

1601

break;

2625

1602

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

2626

1603

seckey = arg;

2628

1605

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

2629

1606

pubkey = arg;

2630

1607

break;

2631

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

2632

#if GNUTLS_VERSION_NUMBER >= 0x030606

2633

tls_privkey = arg;

2634

#endif

2635

break;

2636

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

2637

#if GNUTLS_VERSION_NUMBER >= 0x030606

2638

tls_pubkey = arg;

2639

#endif

2640

break;

2641

1608

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

2642

1609

errno = 0;

2643

1610

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

2647

1614

}

2648

1615

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

2649

1616

break;

2650

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

2651

dh_params_file = arg;

2652

break;

2653

1617

case 130: /* --priority */

2654

1618

mc.priority = arg;

2655

1619

break;

2678

1642

argp_state_help(state, state->out_stream,

2679

1643

(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)

2680

1644

& ~(unsigned int)ARGP_HELP_EXIT_OK);

2681

__builtin_unreachable();

2682

1645

case -3: /* --usage */

2683

1646

argp_state_help(state, state->out_stream,

2684

1647

ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);

2685

__builtin_unreachable();

2686

1648

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

1649

fprintf_plus(state->out_stream,

1650

"Mandos plugin mandos-client: ");

2687

1651

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

2688

1652

exit(argp_err_exit_status);

2689

1653

break;

2697

1661

.args_doc = "",

2698

1662

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

2699

1663

" passwords from a Mandos server" };

2700

ret_errno = argp_parse(&argp, argc, argv,

2701

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

2702

switch(ret_errno){

1664

ret = argp_parse(&argp, argc, argv,

1665

ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);

1666

switch(ret){

2703

1667

case 0:

2704

1668

break;

2705

1669

case ENOMEM:

2706

1670

default:

2707

errno = ret_errno;

1671

errno = ret;

2708

1672

perror_plus("argp_parse");

2709

1673

exitcode = EX_OSERR;

2710

1674

goto end;

2713

1677

goto end;

2714

1678

}

2715

1679

}

2716

2717

{

2718

/* Re-raise privileges */

2719

ret = raise_privileges();

2720

if(ret != 0){

2721

errno = ret;

2722

perror_plus("Failed to raise privileges");

2723

} else {

2724

struct stat st;

2725

2726

/* Work around Debian bug #633582:

2727

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

2728

2729

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

2730

int seckey_fd = open(seckey, O_RDONLY);

2731

if(seckey_fd == -1){

2732

perror_plus("open");

2733

} else {

2734

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

2735

if(ret == -1){

2736

perror_plus("fstat");

2737

} else {

2738

if(S_ISREG(st.st_mode)

2739

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

2740

ret = fchown(seckey_fd, uid, gid);

2741

if(ret == -1){

2742

perror_plus("fchown");

2743

}

2744

}

2745

}

2746

close(seckey_fd);

2747

}

2748

}

2749

2750

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

2751

int pubkey_fd = open(pubkey, O_RDONLY);

2752

if(pubkey_fd == -1){

2753

perror_plus("open");

2754

} else {

2755

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

2756

if(ret == -1){

2757

perror_plus("fstat");

2758

} else {

2759

if(S_ISREG(st.st_mode)

2760

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

2761

ret = fchown(pubkey_fd, uid, gid);

2762

if(ret == -1){

2763

perror_plus("fchown");

2764

}

2765

}

2766

}

2767

close(pubkey_fd);

2768

}

2769

}

2770

2771

if(dh_params_file != NULL

2772

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

2773

int dhparams_fd = open(dh_params_file, O_RDONLY);

2774

if(dhparams_fd == -1){

2775

perror_plus("open");

2776

} else {

2777

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

2778

if(ret == -1){

2779

perror_plus("fstat");

2780

} else {

2781

if(S_ISREG(st.st_mode)

2782

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

2783

ret = fchown(dhparams_fd, uid, gid);

2784

if(ret == -1){

2785

perror_plus("fchown");

2786

}

2787

}

2788

}

2789

close(dhparams_fd);

2790

}

2791

}

2792

2793

/* Work around Debian bug #981302

2794

<https://bugs.debian.org/981302> */

2795

if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){

2796

ret = symlink("/proc/self/fd", "/dev/fd");

2797

if(ret == -1){

2798

perror_plus("Failed to create /dev/fd symlink");

2799

}

2800

}

2801

2802

/* Lower privileges */

2803

ret = lower_privileges();

2804

if(ret != 0){

2805

errno = ret;

2806

perror_plus("Failed to lower privileges");

2807

}

2808

}

2809

}

2810

2811

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

2812

{

2813

char *interface = NULL;

2814

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

2815

interface))){

2816

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

2817

and if_nametoindex(interface) == 0){

2818

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

2819

fprintf_plus(stderr, "Not using nonexisting interface"

2820

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

2821

}

2822

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

2823

interface = NULL;

2824

}

1680

1681

if(getuid() == 0){

1682

/* Work around Debian bug #633582:

1683

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

1684

struct stat st;

1685

1686

/* Re-raise priviliges */

1687

errno = 0;

1688

ret = seteuid(0);

1689

if(ret == -1){

1690

perror_plus("seteuid");

1691

}

1692

1693

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

1694

int seckey_fd = open(seckey, O_RDONLY);

1695

if(seckey_fd == -1){

1696

perror_plus("open");

1697

} else {

1698

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

1699

if(ret == -1){

1700

perror_plus("fstat");

1701

} else {

1702

if(S_ISREG(st.st_mode)

1703

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

1704

ret = fchown(seckey_fd, uid, gid);

1705

if(ret == -1){

1706

perror_plus("fchown");

1707

}

1708

}

1709

}

1710

TEMP_FAILURE_RETRY(close(seckey_fd));

1711

}

1712

}

1713

1714

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

1715

int pubkey_fd = open(pubkey, O_RDONLY);

1716

if(pubkey_fd == -1){

1717

perror_plus("open");

1718

} else {

1719

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

1720

if(ret == -1){

1721

perror_plus("fstat");

1722

} else {

1723

if(S_ISREG(st.st_mode)

1724

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

1725

ret = fchown(pubkey_fd, uid, gid);

1726

if(ret == -1){

1727

perror_plus("fchown");

1728

}

1729

}

1730

}

1731

TEMP_FAILURE_RETRY(close(pubkey_fd));

1732

}

1733

}

1734

1735

/* Lower privileges */

1736

errno = 0;

1737

ret = seteuid(uid);

1738

if(ret == -1){

1739

perror_plus("seteuid");

2825

1740

}

2826

1741

}

2827

1742

2828

1743

/* Run network hooks */

2829

1744

{

2830

if(mc.interfaces != NULL){

2831

interfaces_hooks = malloc(mc.interfaces_size);

2832

if(interfaces_hooks == NULL){

2833

perror_plus("malloc");

2834

goto end;

2835

}

2836

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

2837

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

2838

}

2839

run_network_hooks("start", interfaces_hooks != NULL ?

2840

interfaces_hooks : "", delay);

1745

if(getuid() == 0){

1746

/* Re-raise priviliges */

1747

errno = 0;

1748

ret = seteuid(0);

1749

if(ret == -1){

1750

perror_plus("seteuid");

1751

}

1752

}

1753

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

1754

goto end;

1755

}

1756

if(getuid() == 0){

1757

/* Lower privileges */

1758

errno = 0;

1759

ret = seteuid(uid);

1760

if(ret == -1){

1761

perror_plus("seteuid");

1762

}

1763

}

2841

1764

}

2842

1765

2843

1766

if(not debug){

2844

1767

avahi_set_log_function(empty_log);

2845

1768

}

2846

1769

1770

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

1771

struct dirent **direntries;

1772

/* First look for interfaces that are up */

1773

ret = scandir(sys_class_net, &direntries, up_interface,

1774

alphasort);

1775

if(ret == 0){

1776

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

1777

free(direntries);

1778

ret = scandir(sys_class_net, &direntries, good_interface,

1779

alphasort);

1780

}

1781

if(ret >= 1){

1782

/* Pick the first interface returned */

1783

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

1784

if(debug){

1785

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

1786

}

1787

if(interface == NULL){

1788

perror_plus("malloc");

1789

free(direntries);

1790

exitcode = EXIT_FAILURE;

1791

goto end;

1792

}

1793

free(direntries);

1794

} else {

1795

free(direntries);

1796

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

1797

exitcode = EXIT_FAILURE;

1798

goto end;

1799

}

1800

}

1801

2847

1802

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

2848

1803

from the signal handler */

2849

1804

/* Initialize the pseudo-RNG for Avahi */

2850

1805

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

2851

simple_poll = avahi_simple_poll_new();

2852

if(simple_poll == NULL){

1806

mc.simple_poll = avahi_simple_poll_new();

1807

if(mc.simple_poll == NULL){

2853

1808

fprintf_plus(stderr,

2854

1809

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

2855

1810

exitcode = EX_UNAVAILABLE;

2919

1874

}

2920

1875

}

2921

1876

2922

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

2923

if(mc.interfaces == NULL){

2924

struct dirent **direntries = NULL;

2925

/* Look for any good interfaces */

2926

ret = scandir(sys_class_net, &direntries, good_interface,

2927

alphasort);

2928

if(ret >= 1){

2929

/* Add all found interfaces to interfaces list */

2930

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

2931

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

2932

direntries[i]->d_name);

2933

if(ret_errno != 0){

2934

errno = ret_errno;

2935

perror_plus("argz_add");

2936

free(direntries[i]);

2937

continue;

2938

}

2939

if(debug){

2940

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

2941

direntries[i]->d_name);

2942

}

2943

free(direntries[i]);

2944

}

2945

free(direntries);

2946

} else {

2947

if(ret == 0){

2948

free(direntries);

2949

}

2950

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

2951

exitcode = EXIT_FAILURE;

2952

goto end;

2953

}

2954

}

2955

2956

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

2957

{

2958

char *interface = NULL;

2959

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

2960

interface))){

2961

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

2962

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

2963

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

2964

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

2965

interface);

2966

interface = NULL;

2967

while((interface = argz_next(mc.interfaces,

2968

mc.interfaces_size, interface))){

2969

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

2970

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

2971

interface);

2972

interface = NULL;

1877

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

1878

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

1879

if_index = (AvahiIfIndex) if_nametoindex(interface);

1880

if(if_index == 0){

1881

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

1882

exitcode = EX_UNAVAILABLE;

1883

goto end;

1884

}

1885

1886

if(quit_now){

1887

goto end;

1888

}

1889

1890

/* Re-raise priviliges */

1891

errno = 0;

1892

ret = seteuid(0);

1893

if(ret == -1){

1894

perror_plus("seteuid");

1895

}

1896

1897

#ifdef __linux__

1898

/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO

1899

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

1900

ret = klogctl(8, NULL, 5);

1901

bool restore_loglevel = true;

1902

if(ret == -1){

1903

restore_loglevel = false;

1904

perror_plus("klogctl");

1905

}

1906

#endif /* __linux__ */

1907

1908

sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);

1909

if(sd < 0){

1910

perror_plus("socket");

1911

exitcode = EX_OSERR;

1912

#ifdef __linux__

1913

if(restore_loglevel){

1914

ret = klogctl(7, NULL, 0);

1915

if(ret == -1){

1916

perror_plus("klogctl");

1917

}

1918

}

1919

#endif /* __linux__ */

1920

/* Lower privileges */

1921

errno = 0;

1922

ret = seteuid(uid);

1923

if(ret == -1){

1924

perror_plus("seteuid");

1925

}

1926

goto end;

1927

}

1928

strcpy(network.ifr_name, interface);

1929

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

1930

if(ret == -1){

1931

perror_plus("ioctl SIOCGIFFLAGS");

1932

#ifdef __linux__

1933

if(restore_loglevel){

1934

ret = klogctl(7, NULL, 0);

1935

if(ret == -1){

1936

perror_plus("klogctl");

1937

}

1938

}

1939

#endif /* __linux__ */

1940

exitcode = EX_OSERR;

1941

/* Lower privileges */

1942

errno = 0;

1943

ret = seteuid(uid);

1944

if(ret == -1){

1945

perror_plus("seteuid");

1946

}

1947

goto end;

1948

}

1949

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

1950

network.ifr_flags |= IFF_UP;

1951

take_down_interface = true;

1952

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

1953

if(ret == -1){

1954

take_down_interface = false;

1955

perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");

1956

exitcode = EX_OSERR;

1957

#ifdef __linux__

1958

if(restore_loglevel){

1959

ret = klogctl(7, NULL, 0);

1960

if(ret == -1){

1961

perror_plus("klogctl");

2973

1962

}

2974

1963

}

1964

#endif /* __linux__ */

1965

/* Lower privileges */

1966

errno = 0;

1967

ret = seteuid(uid);

1968

if(ret == -1){

1969

perror_plus("seteuid");

1970

}

1971

goto end;

1972

}

1973

}

1974

/* Sleep checking until interface is running.

1975

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

1976

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

1977

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

1978

if(ret == -1){

1979

perror_plus("ioctl SIOCGIFFLAGS");

1980

} else if(network.ifr_flags & IFF_RUNNING){

2975

1981

break;

2976

1982

}

2977

bool interface_was_up = interface_is_up(interface);

2978

errno = bring_up_interface(interface, delay);

2979

if(not interface_was_up){

2980

if(errno != 0){

2981

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

2982

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

2983

} else {

2984

errno = argz_add(&interfaces_to_take_down,

2985

&interfaces_to_take_down_size,

2986

interface);

2987

if(errno != 0){

2988

perror_plus("argz_add");

2989

}

2990

}

2991

}

2992

}

2993

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

2994

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

2995

}

2996

}

2997

2998

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

2999

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

3000

if(debug){

3001

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

3002

mc.interfaces);

3003

}

3004

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

1983

struct timespec sleeptime = { .tv_nsec = 250000000 };

1984

ret = nanosleep(&sleeptime, NULL);

1985

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

1986

perror_plus("nanosleep");

1987

}

1988

}

1989

if(not take_down_interface){

1990

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

1991

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

1992

if(ret == -1){

1993

perror_plus("close");

1994

}

1995

}

1996

#ifdef __linux__

1997

if(restore_loglevel){

1998

/* Restores kernel loglevel to default */

1999

ret = klogctl(7, NULL, 0);

2000

if(ret == -1){

2001

perror_plus("klogctl");

2002

}

2003

}

2004

#endif /* __linux__ */

2005

/* Lower privileges */

2006

errno = 0;

2007

/* Lower privileges */

2008

ret = seteuid(uid);

2009

if(ret == -1){

2010

perror_plus("seteuid");

2011

}

3005

2012

}

3006

2013

3007

2014

if(quit_now){

3008

2015

goto end;

3009

2016

}

3010

2017

3011

#if GNUTLS_VERSION_NUMBER >= 0x030606

3012

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

3013

#elif GNUTLS_VERSION_NUMBER < 0x030600

3014

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

3015

#else

3016

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

3017

#endif

2018

ret = init_gnutls_global(pubkey, seckey);

3018

2019

if(ret == -1){

3019

2020

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

3020

2021

exitcode = EX_UNAVAILABLE;

3027

2028

goto end;

3028

2029

}

3029

2030

3030

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

3031

tempdir = mkdtemp(run_tempdir);

3032

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

3033

if(debug){

3034

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

3035

run_tempdir, old_tempdir);

3036

}

3037

tempdir = mkdtemp(old_tempdir);

3038

}

3039

if(tempdir == NULL){

2031

if(mkdtemp(tempdir) == NULL){

3040

2032

perror_plus("mkdtemp");

3041

2033

goto end;

3042

2034

}

2035

tempdir_created = true;

3043

2036

3044

2037

if(quit_now){

3045

2038

goto end;

3046

2039

}

3047

2040

3048

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

2041

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

3049

2042

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

3050

2043

exitcode = EX_UNAVAILABLE;

3051

2044

goto end;

3061

2054

/* Connect directly, do not use Zeroconf */

3062

2055

/* (Mainly meant for debugging) */

3063

2056

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

3064

3065

2057

if(address == NULL){

3066

2058

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

3067

2059

exitcode = EX_USAGE;

3072

2064

goto end;

3073

2065

}

3074

2066

3075

in_port_t port;

2067

uint16_t port;

3076

2068

errno = 0;

3077

2069

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

3078

2070

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

3079

or tmpmax != (in_port_t)tmpmax){

2071

or tmpmax != (uint16_t)tmpmax){

3080

2072

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

3081

2073

exitcode = EX_USAGE;

3082

2074

goto end;

3083

2075

}

3084

2076

3085

2077

if(quit_now){

3086

2078

goto end;

3087

2079

}

3088

2080

3089

port = (in_port_t)tmpmax;

2081

port = (uint16_t)tmpmax;

3090

2082

*address = '\0';

3091

2083

/* Colon in address indicates IPv6 */

3092

2084

int af;

3108

2100

}

3109

2101

3110

2102

while(not quit_now){

3111

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

3112

&mc);

2103

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

3113

2104

if(quit_now or ret == 0){

3114

2105

break;

3115

2106

}

3117

2108

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

3118

2109

(int)retry_interval);

3119

2110

}

3120

sleep((unsigned int)retry_interval);

2111

sleep((int)retry_interval);

3121

2112

}

3122

2113

3123

if(not quit_now){

2114

if (not quit_now){

3124

2115

exitcode = EXIT_SUCCESS;

3125

2116

}

3126

2117

3141

2132

config.publish_domain = 0;

3142

2133

3143

2134

/* Allocate a new server */

3144

mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),

3145

&config, NULL, NULL, &ret);

2135

mc.server = avahi_server_new(avahi_simple_poll_get

2136

(mc.simple_poll), &config, NULL,

2137

NULL, &error);

3146

2138

3147

2139

/* Free the Avahi configuration data */

3148

2140

avahi_server_config_free(&config);

3151

2143

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

3152

2144

if(mc.server == NULL){

3153

2145

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

3154

avahi_strerror(ret));

2146

avahi_strerror(error));

3155

2147

exitcode = EX_UNAVAILABLE;

3156

2148

goto end;

3157

2149

}

3163

2155

/* Create the Avahi service browser */

3164

2156

sb = avahi_s_service_browser_new(mc.server, if_index,

3165

2157

AVAHI_PROTO_UNSPEC, "_mandos._tcp",

3166

NULL, 0, browse_callback,

3167

(void *)&mc);

2158

NULL, 0, browse_callback, NULL);

3168

2159

if(sb == NULL){

3169

2160

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

3170

2161

avahi_strerror(avahi_server_errno(mc.server)));

3181

2172

if(debug){

3182

2173

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

3183

2174

}

3184

3185

ret = avahi_loop_with_timeout(simple_poll,

3186

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

2175

2176

ret = avahi_loop_with_timeout(mc.simple_poll,

2177

(int)(retry_interval * 1000));

3187

2178

if(debug){

3188

2179

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

3189

2180

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

3192

2183

end:

3193

2184

3194

2185

if(debug){

3195

if(signal_received){

3196

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

3197

argv[0], signal_received,

3198

strsignal(signal_received));

3199

} else {

3200

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

3201

}

2186

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

3202

2187

}

3203

2188

3204

2189

/* Cleanup things */

3205

free(mc.interfaces);

3206

3207

2190

if(sb != NULL)

3208

2191

avahi_s_service_browser_free(sb);

3209

2192

3210

2193

if(mc.server != NULL)

3211

2194

avahi_server_free(mc.server);

3212

2195

3213

if(simple_poll != NULL)

3214

avahi_simple_poll_free(simple_poll);

2196

if(mc.simple_poll != NULL)

2197

avahi_simple_poll_free(mc.simple_poll);

3215

2198

3216

2199

if(gnutls_initialized){

3217

2200

gnutls_certificate_free_credentials(mc.cred);

2201

gnutls_global_deinit();

3218

2202

gnutls_dh_params_deinit(mc.dh_params);

3219

2203

}

3220

2204

3228

2212

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

3229

2213

while(mc.current_server != NULL){

3230

2214

server *next = mc.current_server->next;

3231

#ifdef __GNUC__

3232

#pragma GCC diagnostic push

3233

#pragma GCC diagnostic ignored "-Wcast-qual"

3234

#endif

3235

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

3236

#ifdef __GNUC__

3237

#pragma GCC diagnostic pop

3238

#endif

3239

2215

free(mc.current_server);

3240

2216

mc.current_server = next;

3241

2217

}

3242

2218

}

3243

2219

3244

/* Re-raise privileges */

2220

/* Re-raise priviliges */

3245

2221

{

3246

ret = raise_privileges();

3247

if(ret != 0){

3248

errno = ret;

3249

perror_plus("Failed to raise privileges");

3250

} else {

3251

3252

/* Run network hooks */

3253

run_network_hooks("stop", interfaces_hooks != NULL ?

3254

interfaces_hooks : "", delay);

3255

3256

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

3257

{

3258

char *interface = NULL;

3259

while((interface = argz_next(interfaces_to_take_down,

3260

interfaces_to_take_down_size,

3261

interface))){

3262

ret = take_down_interface(interface);

3263

if(ret != 0){

3264

errno = ret;

3265

perror_plus("Failed to take down interface");

3266

}

3267

}

3268

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

3269

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

3270

" down\n");

3271

}

3272

}

3273

}

3274

3275

ret = lower_privileges_permanently();

3276

if(ret != 0){

3277

errno = ret;

3278

perror_plus("Failed to lower privileges permanently");

3279

}

3280

}

3281

3282

free(interfaces_to_take_down);

3283

free(interfaces_hooks);

3284

3285

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

3286

uintmax_t level){

2222

if(getuid() == 0){

2223

errno = 0;

2224

ret = seteuid(0);

2225

if(ret == -1){

2226

perror_plus("seteuid");

2227

}

2228

}

2229

2230

/* Run network hooks */

2231

run_network_hooks("stop", interface, delay);

2232

2233

/* Take down the network interface */

2234

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

2235

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

2236

if(ret == -1){

2237

perror_plus("ioctl SIOCGIFFLAGS");

2238

} else if(network.ifr_flags & IFF_UP){

2239

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

2240

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

2241

if(ret == -1){

2242

perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");

2243

}

2244

}

2245

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

2246

if(ret == -1){

2247

perror_plus("close");

2248

}

2249

}

2250

}

2251

if(getuid() == 0){

2252

/* Lower privileges permanently */

2253

errno = 0;

2254

ret = setuid(uid);

2255

if(ret == -1){

2256

perror_plus("setuid");

2257

}

2258

}

2259

2260

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

2261

if(tempdir_created){

3287

2262

struct dirent **direntries = NULL;

3288

int dret;

3289

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

3290

O_RDONLY

3291

| O_NOFOLLOW

3292

| O_DIRECTORY

3293

| O_PATH));

3294

if(dir_fd == -1){

3295

perror_plus("open");

3296

return;

3297

}

3298

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

3299

notdotentries, alphasort);

3300

if(numentries >= 0){

2263

struct dirent *direntry = NULL;

2264

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

2265

alphasort);

2266

if (numentries > 0){

3301

2267

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

3302

if(debug){

3303

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

3304

dirname, direntries[i]->d_name);

3305

}

3306

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

3307

if(dret == -1){

3308

if(errno == EISDIR){

3309

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

3310

AT_REMOVEDIR);

3311

}

3312

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

3313

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

3314

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

3315

/* Recurse only in this special case */

3316

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

3317

dret = 0;

3318

}

3319

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

3320

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

3321

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

3322

}

3323

}

3324

free(direntries[i]);

3325

}

3326

3327

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

3328

free(direntries);

3329

dret = unlinkat(base, dirname, AT_REMOVEDIR);

3330

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

3331

perror_plus("rmdir");

3332

}

3333

} else {

3334

perror_plus("scandirat");

3335

}

3336

close(dir_fd);

3337

}

3338

3339

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

3340

if(tempdir != NULL){

3341

clean_dir_at(-1, tempdir, 0);

2268

direntry = direntries[i];

2269

char *fullname = NULL;

2270

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

2271

direntry->d_name);

2272

if(ret < 0){

2273

perror_plus("asprintf");

2274

continue;

2275

}

2276

ret = remove(fullname);

2277

if(ret == -1){

2278

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

2279

strerror(errno));

2280

}

2281

free(fullname);

2282

}

2283

}

2284

2285

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

2286

free(direntries);

2287

if (numentries == -1){

2288

perror_plus("scandir");

2289

}

2290

ret = rmdir(tempdir);

2291

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

2292

perror_plus("rmdir");

2293

}

3342

2294

}

3343

2295

3344

2296

if(quit_now){